c-peptide has been researched along with Diabetes-Mellitus--Type-1* in 2067 studies
152 review(s) available for c-peptide and Diabetes-Mellitus--Type-1
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The Predictive Ability of C-Peptide in Distinguishing Type 1 Diabetes From Type 2 Diabetes: A Systematic Review and Meta-Analysis.
This systematic review and meta-analysis aimed to investigate the predictive ability of plasma connecting peptide (C-peptide) levels in discriminating type 1 diabetes (T1D) from type 2 diabetes (T2D) and to inform evidence-based guidelines in diabetes classification.. We conducted a holistic review and meta-analysis using PubMed, MEDLINE, EMBASE, and Scopus. The citations were screened from 1942 to 2021. The quality criteria and the preferred reporting items for systematic reviews and meta-analysis checklist were applied. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022355088).. A total of 23,658 abstracts were screened and 46 full texts reviewed. Of the 46 articles screened, 12 articles were included for the meta-analysis. Included studies varied by race, age, time, and proportion of individuals. The main outcome measure in all studies was C-peptide levels. A significant association was reported between C-peptide levels and the classification and diagnosis of diabetes. Furthermore, lower concentrations and the cutoff of <0.20 nmol/L for fasting or random plasma C-peptide was indicative of T1D. In addition, this meta-analysis revealed the predictive ability of C-peptide levels in discriminating T1D from T2D. Results were consistent using both fixed- and random-effect models. The I. Plasma C-peptide levels are highly associated and predictive of the accurate classification and diagnosis of diabetes types. A plasma C-peptide cutoff of ≤0.20 mmol/L is indicative of T1D and of ≥0.30 mmol/L in the fasting or random state is indicative of T2D. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans | 2023 |
Higher Fasting Pretransplant C-peptide Levels in Type 2 Diabetics Undergoing Simultaneous Pancreas-kidney Transplantation Are Associated With Posttransplant Pancreatic Graft Dysfunction.
Among selected patients with type 2 diabetes mellitus (T2DM), simultaneous pancreas and kidney (SPK) transplants can be an effective option. However, data are limited about outcomes in T2DM SPK recipients based on the pretransplant C-peptide levels.. In this study, we reviewed all T2DM SPK recipients and categorized them based on the pretransplant fasting C-peptide levels into 3 groups: low (≤2 ng/mL), medium (>2-8 ng/mL), and high (>8 ng/mL). Several measures of graft failures (GFs), graft dysfunction, and composite outcomes were of interest.. There were a total of 76 SPK recipients (low, n = 14; medium, n = 47; high, n = 15). At the last follow-up, the low group did not reach any outcome; in contrast, 11 (23%) in the medium group and 5 (33%) in the high group reached the uncensored composite outcome; 6 (13%) in the medium group and 2 (13%) in the high group had GF; and 8 (17%) in the medium group and 4 (26.7%) in the high group reached the death-censored composite outcomes. In a fully adjusted model, each pretransplant C-peptide unit was not associated with an increased risk of the composite outcome, GF, or death-censored composite outcomes. However, in multivariate analysis with limited adjustment, pretransplant C-peptide was associated with the composite outcome (hazard ratio: 1.18, 95% confidence interval, 1.01-1.38; P = 0.03) and death-censored composite outcome (hazard ratio: 1.20; 95% confidence interval, 1.01-1.42; P = 0.03).. Although limited by the small sample size, we found excellent outcomes among T2DM SPK recipients overall. However, higher levels of pretransplant C-peptide may be associated with inferior posttransplant outcomes that include graft dysfunction. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Graft Survival; Humans; Kidney Transplantation; Pancreas; Pancreas Transplantation | 2023 |
Risk Factors and Characteristics of Checkpoint Inhibitor-Associated Autoimmune Diabetes Mellitus (CIADM): A Systematic Review and Delineation From Type 1 Diabetes.
Checkpoint inhibitor-associated autoimmune diabetes mellitus (CIADM) is a distinct form of autoimmune diabetes that is a rare complication of immune checkpoint inhibitor therapy. Data regarding CIADM are limited.. To systematically review available evidence to identify presentation characteristics and risk factors for early or severe presentations of adult patients with CIADM.. MEDLINE and PubMed databases were reviewed.. English full text articles from 2014 to April 2022 were identified with a predefined search strategy. Patients meeting diagnostic criteria for CIADM with evidence of hyperglycemia (blood glucose level >11 mmol/L or HbA1c ≥6.5%) and insulin deficiency (C-peptide <0.4 nmol/L and/or diabetic ketoacidosis [DKA]) were included for analysis.. With the search strategy we identified 1,206 articles. From 146 articles, 278 patients were labeled with "CIADM," with 192 patients meeting our diagnostic criteria and included in analysis.. Mean ± SD age was 63.4 ± 12.4 years. All but one patient (99.5%) had prior exposure to either anti-PD1 or anti-PD-L1 therapy. Of the 91 patients tested (47.3%), 59.3% had susceptibility haplotypes for type 1 diabetes (T1D). Median time to CIADM onset was 12 weeks (interquartile range 6-24). DKA occurred in 69.7%, and initial C-peptide was low in 91.6%. T1D autoantibodies were present in 40.4% (73 of 179) and were significantly associated with DKA (P = 0.0009) and earlier time to CIADM onset (P = 0.02).. Reporting of follow-up data, lipase, and HLA haplotyping was limited.. CIADM commonly presents in DKA. While T1D autoantibodies are only positive in 40.4%, they associate with earlier, more severe presentations. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Humans; Insulin, Regular, Human; Middle Aged; Risk Factors | 2023 |
Efficacy of anti-CD3 monoclonal antibodies in delaying the progression of recent-onset type 1 diabetes mellitus: A systematic review, meta-analyses and meta-regression.
Type 1 diabetes mellitus is widely recognized as a chronic autoimmune disease characterized by the pathogenic destruction of beta cells, resulting in the loss of endogenous insulin production. Insulin administration remains the primary therapy for symptomatic treatment. Recent studies showed that disease-modifying agents, such as anti-CD3 monoclonal antibodies, have shown promising outcomes in improving the management of the disease. In late 2022, teplizumab received approval from the US Food and Drug Administration (FDA) as the first disease-modifying agent for the treatment of type 1 diabetes. This review aims to evaluate the clinical evidence regarding the efficacy of anti-CD3 monoclonal antibodies in the prevention and treatment of type 1 diabetes.. A comprehensive search of PubMed, Google Scholar, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) was conducted up to December 2022 to identify relevant randomized controlled trials. Meta-analysis was performed using a random-effects model, and odds ratios with 95% confidence intervals (CIs) were calculated to quantify the effects. The Cochrane risk of bias tool was employed for quality assessment.. In total, 11 randomized controlled trials involving 1397 participants (908 participants in the intervention arm, 489 participants in the control arm) were included in this review. The mean age of participants was 15 years, and the mean follow-up time was 2.04 years. Teplizumab was the most commonly studied intervention. Compared with placebo, anti-CD3 monoclonal antibody treatment significantly increased the C-peptide concentration in the area under the curve at shorter timeframes (mean difference = 0.114, 95% CI: 0.069 to 0.159, p = .000). Furthermore, anti-CD3 monoclonal antibodies significantly reduced the patients' insulin intake across all timeframes (mean difference = -0.123, 95% CI: -0.151 to -0.094, p < .001). However, no significant effect on glycated haemoglobin concentration was observed.. The findings of this review suggest that anti-CD3 monoclonal antibody treatment increases endogenous insulin production and improves the lifestyle of patients by reducing insulin dosage. Future studies should consider the limitations, including sample size, heterogeneity and duration of follow-up, to validate the generalizability of these findings further. Topics: Adolescent; Antibodies, Monoclonal; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Humans; Insulin | 2023 |
C-peptide and metabolic outcomes in trials of disease modifying therapy in new-onset type 1 diabetes: an individual participant meta-analysis.
Metabolic outcomes in type 1 diabetes remain suboptimal. Disease modifying therapy to prevent β-cell loss presents an alternative treatment framework but the effect on metabolic outcomes is unclear. We, therefore, aimed to define the relationship between insulin C-peptide as a marker of β-cell function and metabolic outcomes in new-onset type 1 diabetes.. 6 months after treatment, a 24·8% greater C-peptide preservation in positive studies was associated with a 0·55% lower HbA. Interventions that preserve β-cell function are effective at improving metabolic outcomes in new-onset type 1 diabetes, confirming their potential as adjuncts to insulin. We have shown that improvements in HbA. JDRF and Diabetes UK. Topics: Adult; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin | 2023 |
The Potential Role of C-peptide in Sexual and Reproductive Functions in Type 1 Diabetes Mellitus: An Update.
Although hyperglycaemia is known to be the leading cause of diabetic complications, the beneficial effect of optimal glucose control in preventing diabetic complications is still far from being proven. In fact, such complications may not be related to glycaemic control alone.. This review summarizes several studies that suggest that a C-peptide deficiency could be new and common pathophysiology for complications in type 1 diabetes, including sexual and reproductive dysfunction.. We reviewed in vitro, in vivo, and human studies on the association between C-peptide deficiency or C-peptide replacement therapy and complications in type 1 diabetes. It seems that Cpeptide replacement therapy may interrupt the connection between diabetes and sexual/reproductive dysfunction.. The Diabetes Control and Complications Trial suggested that maintaining C-peptide secretion is associated with a reduced incidence of retinopathy, nephropathy, and hypoglycaemia. Risk of vascular, hormonal, and neurologic damage in the structures supplying blood to the penis increases with increasing levels of HbA1. However, several human studies have suggested an association between C-peptide production and hypothalamic/pituitary functions. When exposed to C-peptide, cavernosal smooth muscle cells increase the production of nitric oxide. C-peptide in diabetic rats improves sperm count, sperm motility, testosterone levels, and nerve conduction compared to non-treated diabetic rats.. C-peptide deficiency may be involved, at least partially, in the development of several pathological features associated with type 1 diabetes, including sexual/reproductive dysfunction. Preliminary studies have reported that C-peptide administration protects against diabetic microand macrovascular damages as well as sexual/reproductive dysfunction. Therefore, further studies are needed to confirm these promising findings. Topics: Animals; C-Peptide; Diabetes Complications; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Humans; Male; Rats; Sperm Motility | 2022 |
Association between treatment effect on C-peptide preservation and HbA1c in meta-analysis of glutamic acid decarboxylase (GAD)-alum immunotherapy in recent-onset type 1 diabetes.
Topics: Alum Compounds; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Immunologic Factors; Immunotherapy | 2022 |
Partial Clinical Remission of Type 1 Diabetes: The Need for an Integrated Functional Definition Based on Insulin-Dose Adjusted A1c and Insulin Sensitivity Score.
Despite advances in the characterization of partial clinical remission (PR) of type 1 diabetes, an accurate definition of PR remains problematic. Two recent studies in children with new-onset T1D demonstrated serious limitations of the present gold standard definition of PR, a stimulated C-peptide (SCP) concentration of >300 pmol/L. The first study employed the concept of insulin sensitivity score (ISS) to show that 55% of subjects with new-onset T1D and a detectable SCP level of >300 pmol/L had low insulin sensitivity (IS) and thus might not be in remission when assessed by insulin-dose adjusted A1c (IDAA1c), an acceptable clinical marker of PR. The second study, a randomized controlled trial of vitamin D (ergocalciferol) administration in children and adolescents with new-onset T1D, demonstrated no significant difference in SCP between the ergocalciferol and placebo groups, but showed a significant blunting of the temporal trend in both A1c and IDAA1c in the ergocalciferol group. These two recent studies indicate the poor specificity and sensitivity of SCP to adequately characterize PR and thus call for a re-examination of current approaches to the definition of PR. They demonstrate the limited sensitivity of SCP, a static biochemical test, to detect the complex physiological changes that occur during PR such as changes in insulin sensitivity, insulin requirements, body weight, and physical activity. These shortcomings call for a broader definition of PR using a combination of functional markers such as IDAA1c and ISS to provide a valid assessment of PR that reaches beyond the static changes in SCP alone. Topics: Adolescent; Biomarkers; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Ergocalciferols; Exercise; Glycated Hemoglobin; Health Status Indicators; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Randomized Controlled Trials as Topic; Remission Induction | 2022 |
C-peptide determination in the diagnosis of type of diabetes and its management: A clinical perspective.
Impaired beta-cell function is a recognized cornerstone of diabetes pathophysiology. Estimates of insulin secretory capacity are useful to inform clinical practice, helping to classify types of diabetes, complication risk stratification and to guide treatment decisions. Because C-peptide secretion mirrors beta-cell function, it has emerged as a valuable clinical biomarker, mainly in autoimmune diabetes and especially in adult-onset diabetes. Nonetheless, the lack of robust evidence about the clinical utility of C-peptide measurement in type 2 diabetes, where insulin resistance is a major confounder, limits its use in such cases. Furthermore, problems remain in the standardization of the assay for C-peptide, raising concerns about comparability of measurements between different laboratories. To approach the heterogeneity and complexity of diabetes, reliable, simple and inexpensive clinical markers are required that can inform clinicians about probable pathophysiology and disease progression, and so enable personalization of management and therapy. This review summarizes the current evidence base about the potential value of C-peptide in the management of the two most prevalent forms of diabetes (type 2 diabetes and autoimmune diabetes) to address how its measurement may assist daily clinical practice and to highlight current limitations and areas of uncertainties to be covered by future research. Topics: Adult; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Insulin Secretion | 2022 |
Anti-CD3 monoclonal antibodies for the prevention and treatment of type 1 diabetes: A literature review.
Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of beta cells, resulting in a loss of insulin production. Patients with T1D carry a substantial disease burden as well as substantial short-term and long-term risks associated with inadequate glycemic control. Currently, treatment mainly consists of insulin, which only treats the symptoms of T1D and not the root cause. Thus, disease-modifying agents such as anti-CD3 monoclonal antibodies (mAbs) that target the autoimmune destruction of beta cells in T1D would provide significant relief and health benefits for patients with T1D. This review summarizes the clinical evidence regarding the safety and efficacy of anti-CD3 mAbs in the prevention and treatment of T1D.. A total of 27 studies reporting or evaluating data from clinical trials involving otelixizumab and teplizumab were included in the review. Anti-CD3 mAbs have shown significant benefits in both patients at high risk for T1D and those with recent-onset T1D. In high-risk populations, anti-CD3 mAbs delayed time to diagnosis, preserved C-peptide levels, and improved metabolic parameters. In recent-onset T1D, anti-CD3 mAbs preserved C-peptide levels and reduced insulin needs for extended periods. Anti-CD3 mAb therapy appears to be safe, with primarily transient and self-limiting adverse effects and no negative long-term effects.. Anti-CD3 mAbs are promising disease-modifying treatments for T1D. Their role in T1D may introduce short-term and long-term benefits with the potential to mitigate the significant disease burden; however, more evidence is required for an accurate assessment. Topics: Antibodies, Monoclonal; C-Peptide; CD3 Complex; Diabetes Mellitus, Type 1; Humans; Insulin | 2022 |
Clinical efficacy of stem-cell therapy on diabetes mellitus: A systematic review and meta-analysis.
This systematic literature review aims to compare the efficacy and safety of traditional and stem cell (SC) therapies for type 1 (T1DM) and type 2 (T2DM) diabetes mellitus patients.. The PubMed, SciELO, BVS, and Medline databases were searched, and 38 original articles were selected, which included 647 control cases and 654 treatments with three-, six- and twelve-month follow-ups of T1DM and T2DM patients. The efficacy of stem cell therapy was validated by comparing laboratory parameters such as fasting blood glucose and C-peptide levels before and after treatment. The REML model was chosen for random effects, and the inverse of variance was used for fixed effects. The statistical analysis was carried out using Bioestat 5.0 and STATA 16.0 software.. All SC treatments significantly reduced the need for insulin following six and twelve months of treatment, whereas there was no significant decrease after three months. Fasting blood glucose and glycosylated hemoglobin levels were significantly reduced in all follow-ups with SC. In addition, SC treatment caused a significant increase in C-peptide levels. Bone marrow hematopoietic stem cell therapy produced better results than the conventional drug treatment for diabetes mellitus (semagglutide).. The results with SC were significantly better, regardless of the follow-up period. Studies have proven cell therapy to be beneficial, safe, and effective. Topics: Blood Glucose; C-Peptide; Cell- and Tissue-Based Therapy; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Treatment Outcome | 2022 |
Vitamin D and Beta Cells in Type 1 Diabetes: A Systematic Review.
The prevalence of type 1 diabetes (T1D) is rising steadily. A potential contributor to the rise is vitamin D. In this systematic review, we examined the literature around vitamin D and T1D. We identified 22 papers examining the role of vitamin D in cultured β-cell lines, islets, or perfused pancreas, and 28 papers examining vitamin D in humans or human islets. The literature reports strong associations between T1D and low circulating vitamin D. There is also high-level (systematic reviews, meta-analyses) evidence that adequate vitamin D status in early life reduces T1D risk. Several animal studies, particularly in NOD mice, show harm from D-deficiency and benefit in most studies from vitamin D treatment/supplementation. Short-term streptozotocin studies show a β-cell survival effect with supplementation. Human studies report associations between VDR polymorphisms and T1D risk and β-cell function, as assessed by C-peptide. In view of those outcomes, the variable results in human trials are generally disappointing. Most studies using 1,25D, the active form of vitamin D were ineffective. Similarly, studies using other forms of vitamin D were predominantly ineffective. However, it is interesting to note that all but one of the studies testing 25D reported benefit. Together, this suggests that maintenance of optimal circulating 25D levels may reduce the risk of T1D and that it may have potential for benefits in delaying the development of absolute or near-absolute C-peptide deficiency. Given the near-complete loss of β-cells by the time of clinical diagnosis, vitamin D is much less likely to be useful after disease-onset. However, given the very low toxicity of 25D, and the known benefits of preservation of C-peptide positivity for long-term complications risk, we recommend considering daily cholecalciferol supplementation in people with T1D and people at high risk of T1D, especially if they have vitamin D insufficiency. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Humans; Mice; Mice, Inbred NOD; Vitamin D; Vitamins | 2022 |
C-peptide and residual β-cell function in pediatric diabetes - state of the art.
C-peptide, the molecule produced in an equimolar concentration to insulin, has become an established insulin secretion biomarker in diabetic patients. Measurement of C-peptide level can be helpful in clinical practice for assessing insulin-producing b-cells residual function, especially in the patients who have already started exogenous insulin therapy. Advances in assays have made measurement of C-peptide more reliable and inexpensive. Traditionally, C-peptide is widely used to differentiate between type 1, type 2 and monogenic types in diabetic patients of all ages, both when the diabetes occurs and even months and years after the initial diagnosis. Moreover, in the patients with type 1 diabetes, the C-peptide secretion can become a reliable predictor of the clinical partial remission in the first months after diagnosis, although noteworthy, its' any specified level is not included in the definition of this phase of the disease. Many other clinical factors such as age, use of innovative technologies, the intensity of physical activity or body mass influence the concentration of C-peptide as well as diabetes remission occurrence and duration. They may interfere the interpretation of C-peptide level in the diabetes course. There is a great need to assess the new, adjusted C-peptide levels in these situations. A multitude novel therapies including immunomodulative factors and stem cell transplants can also use C-peptide in the patient selection and post-therapeutic monitoring of the outcome in researches aimed in extension of remission period. Recent research proves C-peptide presence and preserved function and being the possible important player in better metabolic control in long-lasting diabetes type 1. These findings may open the area for trials to regenerate b-cells and save endogenous insulin secretion for many years after diagnosis. Last but not the least, C-peptide presents its own physiological effect on other tissues, among others on the endothelial function, thus participates in inhibiting micro- and macrovascular diabetes complications. The idea of C-peptide as a new, additional to insulin cure remains as much attractive as elusive.. C-peptyd – cząsteczka produkowana w równym stężeniu z insuliną, stał się uznanym biomarkerem wydzielania insuliny u osób chorujących na cukrzycę. Pomiar jego stężenia może być pomocny w praktyce klinicznej w ocenie resztkowej funkcji komórek b produkujących insulinę, zwłaszcza u pacjentów, którzy rozpoczęli już terapię insuliną egzogenną. Postęp w dziedzinie metod pomiarowych sprawił, że pomiar C-peptydu stał się z czasem coraz bardziej wiarygodny oraz niedrogi. Tradycyjnie C-peptyd jest szeroko stosowany do różnicowania między typem 1, typem 2 i typami monogenowymi u pacjentów z cukrzycą w każdym wieku, zarówno w momencie wystąpienia cukrzycy, jak nawet miesiące czy lata po jej rozpoznaniu. Co więcej, u chorych na cukrzycę typu 1 wydzielanie C-peptydu może stać się wiarygodnym predyktorem częściowej remisji klinicznej w pierwszych miesiącach po rozpoznaniu choroby, chociaż, co warte podkreślenia, jego poziom nie mieści się w definicji tej fazy choroby. Wiele innych czynników klinicznych, takich jak wiek, stosowanie innowacyjnych technologii, intensywność aktywności fizycznej czy masa ciała, wpływa na stężenie C-peptydu oraz na wystąpienie i czas trwania remisji cukrzycy. Mogą one zaburzać interpretację stężenia C-peptydu w przebiegu choroby. Istnieje zatem istotna potrzeba oceny nowych, skorygowanych wyników pomiaru C-peptydu w tych sytuacjach. Wiele nowych terapii, w tym z użyciem czynników immunomodulacyjnych i przeszczepów komórek macierzystych w badaniach mających na celu wydłużenie okresu remisji, może również wykorzystywać C-peptyd w doborze pacjentów i monitorowaniu wyników terapii. Najnowsze badania dowodzą, że C-peptyd jest obecny i zachowuje swoją funkcję, a także może odgrywać ważną rolę w lepszej kontroli metabolicznej także w długotrwałej cukrzycy typu 1. Wyniki te mogą otworzyć pole do badań mających na celu regenerację komórek b i zachowanie endogennego wydzielania insuliny przez wiele lat po rozpoznaniu choroby. Wreszcie, C-peptyd wykazuje własne fizjologiczne działanie na inne tkanki, między innymi na funkcję śródbłonka, uczestnicząc w ten sposób w hamowaniu mikro- i makronaczyniowych powikłań cukrzycy. Idea C-peptydu jako nowej, dodatkowej, poza insuliną, metody leczenia pozostaje tyleż atrakcyjna, co nieuchwytna. Topics: Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion | 2021 |
Adult-Onset Type 1 Diabetes: Current Understanding and Challenges.
Recent epidemiological data have shown that more than half of all new cases of type 1 diabetes occur in adults. Key genetic, immune, and metabolic differences exist between adult- and childhood-onset type 1 diabetes, many of which are not well understood. A substantial risk of misclassification of diabetes type can result. Notably, some adults with type 1 diabetes may not require insulin at diagnosis, their clinical disease can masquerade as type 2 diabetes, and the consequent misclassification may result in inappropriate treatment. In response to this important issue, JDRF convened a workshop of international experts in November 2019. Here, we summarize the current understanding and unanswered questions in the field based on those discussions, highlighting epidemiology and immunogenetic and metabolic characteristics of adult-onset type 1 diabetes as well as disease-associated comorbidities and psychosocial challenges. In adult-onset, as compared with childhood-onset, type 1 diabetes, HLA-associated risk is lower, with more protective genotypes and lower genetic risk scores; multiple diabetes-associated autoantibodies are decreased, though GADA remains dominant. Before diagnosis, those with autoantibodies progress more slowly, and at diagnosis, serum C-peptide is higher in adults than children, with ketoacidosis being less frequent. Tools to distinguish types of diabetes are discussed, including body phenotype, clinical course, family history, autoantibodies, comorbidities, and C-peptide. By providing this perspective, we aim to improve the management of adults presenting with type 1 diabetes. Topics: Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Insulin | 2021 |
Clinical efficacy on glycemic control and safety of mesenchymal stem cells in patients with diabetes mellitus: Systematic review and meta-analysis of RCT data.
Diabetes mellitus as a chronic metabolic disease is threatening human health seriously. Although numerous clinical trials have been registered for the treatment of diabetes with stem cells, no articles have been published to summarize the efficacy and safety of mesenchymal stem cells (MSCs) in randomized controlled trials (RCTs).. The aim of this study was to systematically review the evidence from RCTs and, where possible, conduct meta-analyses to provide a reliable numerical summary and the most comprehensive assessment of therapeutic efficacy and safety with MSCs in diabetes. PubMed, Web of Science, Ovid, the Cochrane Library and CNKI were searched. The retrieval time was from establishment of these databases to January 4, 2020. Seven RCTs were eligible for analysis, including 413 participants. Meta-analysis results showed that there were no significant differences in the reduction of fasting plasma glucose (FPG) compared to the baseline [mean difference (MD) = -1.05, 95% confidence interval (CI) (-2.26,0.16), P<0.01, I2 = 94%] and the control group [MD = -0.62, 95%CI (-1.46,0.23), P<0.01, I2 = 87%]. The MSCs treatment group showed a significant decrease in hemoglobin (Hb) A1c [random-effects, MD = -1.32, 95%CI (-2.06, -0.57), P<0.01, I2 = 90%] after treatment. Additionally, HbA1c reduced more significantly in MSC treatment group than in control group [random-effects, MD = -0.87, 95%CI (-1.53, -0.22), P<0.01, I2 = 82%] at the end of follow-up. However, as for fasting C-peptide levels, the estimated pooled MD showed that there was no significant increase [MD = -0.07, 95%CI (-0.30, 0.16), P<0.01, I2 = 94%] in MSCs treatment group compared with that in control group. Notably, there was no significant difference in the incidence of adverse events between MSCs treatment group and control group [relative risk (RR) = 0.98, 95%CI (0.72, 1.32), P = 0.02, I2 = 70%]. The most commonly observed adverse reaction in the MSC treatment group was hypoglycemia (29.95%).. This meta-analysis revealed MSCs therapy may be an effective and safe intervention in subjects with diabetes. However, due to the limited studies, a number of high-quality as well as large-scale RCTs should be performed to confirm these conclusions. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Glycated Hemoglobin; Glycemic Control; Humans; Hypoglycemia; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Randomized Controlled Trials as Topic; Treatment Outcome | 2021 |
1921-2021: From insulin discovery to islet transplantation in type 1 diabetes.
One century after the discovery of insulin, the French Health regulations have just authorized the reimbursement for islet transplantation. Intraportal islet allotransplantation from a pancreatic donor is indicated in patients with type 1 diabetes (T1D) complicated with lability or hypoglycemia unawareness, or in case of a functioning kidney graft; islet auto-transplantation may be indicated after pancreatic surgery.Compared with insulin even administered in closed-loop pumps, the specificity of islet allotransplantation is the restoration of C-peptide secretion. Long-term insulin-independence is observed when the engrafted islet mass is sufficient, at the cost of immunosuppression. Fewer low-glucose events and less glucose variability, are observed even with minimal functional islet graft, after islet transplantation as at onset of T1D, when a residual C-peptide secretion is maintained, an objective currently approached with less aggressive immuno-modulating therapies than in the past. Therefore, restoration or preservation of endogen insulin secretion is an important goal, allowing to maintain a long-term glucose balance with more than 70% of time in range 3.9-10mmol/L and less than 3% of time <3.9mmol/L, thus reducing the occurrence of diabetic complications. In the clinical setting, - the preservation of C-peptide at early stage of T1D, - the use of technological ressources (multi-injections, sensors, insulin pump, closed-loop systems) at later stages, - and islet transplantation when hypoglycemia awareness becomes impaired are complementary for a personalized care all along the life of T1D patients. Topics: C-Peptide; Diabetes Mellitus, Type 1; France; Glycemic Control; History, 20th Century; History, 21st Century; Humans; Insulin; Islets of Langerhans Transplantation | 2021 |
Type of diabetes mellitus: Does it matter to the clinician?
The classification of diabetes mellitus in 2020 still starts with 2 major types, ie, type 1 and type 2, but each of these now includes a few uncommon variants. Understanding the many faces of the diabetes syndrome can make a difference in how clinicians select glucose-lowering therapy. Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hyperglycemia; Latent Autoimmune Diabetes in Adults; Phenotype | 2020 |
CTLA4-Ig (abatacept): a promising investigational drug for use in type 1 diabetes.
Topics: Abatacept; Animals; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Humans; Immunosuppressive Agents | 2020 |
[Molecular mechanisms of action and physiological effects of the proinsulin C-peptide (a systematic review)].
The C-peptide is a fragment of proinsulin, the cleavage of which forms active insulin. In recent years, new information has appeared on the physiological effects of the C-peptide, indicating its positive effect on many organs and tissues, including the kidneys, nervous system, heart, vascular endothelium and blood microcirculation. Studies on experimental models of diabetes mellitus in animals, as well as clinical trials in patients with diabetes, have shown that the C-peptide has an important regulatory effect on the early stages of functional and structural disorders caused by this disease. The C-peptide exhibits its effects through binding to a specific receptor on the cell membrane and activation of downstream signaling pathways. Intracellular signaling involves G-proteins and Ca2+-dependent pathways, resulting in activation and increased expression of endothelial nitric oxide synthase, Na+/K+-ATPase and important transcription factors involved in apoptosis, anti-inflammatory and other intracellular defense mechanisms. This review gives an idea of the C-peptide as a bioactive endogenous peptide that has its own biological activity and therapeutic potential.. S-peptid — fragment proinsulina, v rezul'tate otshchepleniia kotorogo obrazuetsia aktivnyĭ insulin. Za poslednie gody poiavilas' novaia informatsiia o fiziologicheskikh éffektakh S-peptida, svidetel'stvuiushchaia o ego polozhitel'nom vliianii na funktsii mnogikh organov i tkaneĭ, v tom chisle pochki, nervnuiu sistemu, serdtse, sosudistyĭ éndoteliĭ i mikrotsirkuliatsiiu krovi. Issledovaniia na zhivotnykh s ispol'zovaniem éksperimental'nykh modeleĭ sakharnogo diabeta, a takzhe klinicheskie nabliudeniia patsientov s sakharnym diabetom prodemonstrirovali, chto S-peptid okazyvaet vazhnoe reguliatornoe vliianie na rannikh stadiiakh funktsional'nykh i strukturnykh narusheniĭ, vyzvannykh étim zabolevaniem. Svoi éffekty S-peptid osushchestvliaet, sviazyvaias' so spetsificheskim retseptorom na kletochnoĭ membrane. Vnutrikletochnaia peredacha signalov osushchestvliaetsia cherez G-belki i Ca2+-zavisimye puti, chto privodit k aktivatsii i povyshennoĭ ékspressii éndotelial'noĭ sintazy oksida azota, Na+/K+-adenozintrifosfatazy i vazhnykh faktorov transkriptsii, uchastvuiushchikh v apoptoze, protivovospalitel'nykh i drugikh vnutrikletochnykh zashchitnykh mekhanizmakh. Tsel' dannogo obzora — dat' predstavlenie o S-peptide kak o bioaktivnom éndogennom peptide, obladaiushchem sobstvennoĭ biologicheskoĭ aktivnost'iu s terapevticheskim potentsialom. Topics: Animals; Anti-Inflammatory Agents; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Signal Transduction | 2020 |
Efficacy and Safety of Stem Cell Therapy for T1DM: An Updated Systematic Review and Meta-Analysis.
The long-term insulin therapy for type 1 diabetes mellitus (T1DM) fails to achieve optimal glycemic control and avoid adverse events simultaneously. Stem cells have unique immunomodulatory capacities and have been considered as a promising interventional strategy for T1DM. Stem cell therapy in T1DM has been tried in many studies. However, the results were controversial. We thus performed a meta-analysis to update the efficacy and safety of stem cell therapy in patients with T1DM.. We systematically searched the Medline, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Web of Science, Wan Fang Data, China National Knowledge Infrastructure, VIP database, and the Chinese Biomedical Literature Database (SinoMed) for relevant studies published before March 19, 2019. The outcomes included parameters for glycemic control (i.e., glycosylated hemoglobin (HbA1c) levels and insulin dosages),. Five randomized controlled trials (RCTs) and eight nonrandomized concurrent control trials (NRCCTs) with a total of 396 individuals were finally included into the meta-analysis. Among RCTs, stem cell therapy could significantly reduce HbA1c levels (MD = -1.20, 95% CI -1.91 to -0.49,. Stem cell therapy for T1DM may improve glycemic control and Topics: Area Under Curve; C-Peptide; Diabetes Mellitus, Type 1; Gastrointestinal Diseases; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Randomized Controlled Trials as Topic; Risk; Stem Cell Transplantation; Treatment Outcome | 2020 |
Biological Activity of c-Peptide in Microvascular Complications of Type 1 Diabetes-Time for Translational Studies or Back to the Basics?
People with type 1 diabetes have an increased risk of developing microvascular complications, which have a negative impact on the quality of life and reduce life expectancy. Numerous studies in animals with experimental diabetes show that c-peptide supplementation exerts beneficial effects on diabetes-induced damage in peripheral nerves and kidneys. There is substantial evidence that c-peptide counteracts the detrimental changes caused by hyperglycemia at the cellular level, such as decreased activation of endothelial nitric oxide synthase and sodium potassium ATPase, and increase in formation of pro-inflammatory molecules mediated by nuclear factor kappa-light-chain-enhancer of activated B cells: cytokines, chemokines, cell adhesion molecules, vascular endothelial growth factor, and transforming growth factor beta. However, despite positive results from cell and animal studies, no successful c-peptide replacement therapies have been developed so far. Therefore, it is important to improve our understanding of the impact of c-peptide on the pathophysiology of microvascular complications to develop novel c-peptide-based treatments. This article aims to review current knowledge on the impact of c-peptide on diabetic neuro- and nephropathy and to evaluate its potential therapeutic role. Topics: Animals; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Humans; Microcirculation; Sodium-Potassium-Exchanging ATPase; Translational Research, Biomedical | 2020 |
The effect of C-peptide on diabetic nephropathy: A review of molecular mechanisms.
C-peptide is a small peptide connecting two chains of proinsulin molecule and is dissociated before the release of insulin. It is secreted in an equimolar amount to insulin from the pancreatic beta-cells into the circulation. Recent evidence demonstrates that it has other physiologic activities beyond its structural function. C-peptide modulates intracellular signaling pathways in various pathophysiologic states and, could potentially be a new therapeutic target for different disorders including diabetic complications. There is growing evidence that c-peptide has modulatory effects on the molecular mechanisms involved in the development of diabetic nephropathy. Although we have little direct evidence, pharmacological properties of c-peptide suggest that it can provide potent renoprotective effects especially, in a c-peptide deficient milieu as in type 1 diabetes mellitus. In this review, we describe possible molecular mechanisms by which c-peptide may improve renal efficiency in a diabetic milieu. Topics: Animals; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans | 2019 |
LADA: A Type of Diabetes in its Own Right?
Latent Autoimmune Diabetes in the Adult, LADA has been investigated less than "classical" type 1 and type 2 diabetes and the criteria for and the relevance of a LADA diagnosis have been challenged. Despite the absence of a genetic background that is exclusive for LADA this form of diabetes displays phenotypic characteristics that distinguish it from other forms of diabetes. LADA is heterogeneous in terms of the impact of autoimmunity and lifestyle factors, something that poses problems to therapy and follow-up, perhaps particularly in those with marginal positivity. Yet, there appears to be clear clinical utility in classifying individuals as LADA. Topics: Adult; Age of Onset; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Islets of Langerhans; Latent Autoimmune Diabetes in Adults | 2019 |
The dual effect of C-peptide on cellular activation and atherosclerosis: Protective or not?
C-peptide is a cleavage product of proinsulin that acts on different type of cells, such as blood and endothelial cells. C-peptide biological effects may be different in type 1 and type 2 diabetes. Besides, there are further evidence for a functional interaction between C-peptide and insulin. In this way, C-peptide has ambiguous effects, acting as an antithrombotic or thrombotic molecule, depending on the physiological environment and disease conditions. Moreover, C-peptide regulates interaction of leucocytes, erythrocytes, and platelets with the endothelium. The beneficial effects include stimulation of nitric oxide production with its subsequent release by platelets and endothelium, the interaction with erythrocytes leading to the generation of adenosine triphosphate, and inhibition of atherogenic cytokine release. The undesirable action of C-peptide includes the chemotaxis of monocytes, lymphocytes, and smooth muscle cells. Also, C-peptide was related with increased lipid deposits and elevated smooth muscle cells proliferation in the vessel wall, contributing to atherosclerosis. Purpose of this review is to explore these dual roles of C-peptide on the blood, contributing at one side to haemostasis and the other to atherosclerotic process. Topics: Animals; Atherosclerosis; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Endothelium, Vascular; Erythrocytes; Humans; Nitric Oxide | 2019 |
Beta cells in type 1 diabetes: mass and function; sleeping or dead?
Histological analysis of donor pancreases coupled with measurement of serum C-peptide in clinical cohorts has challenged the idea that all beta cells are eventually destroyed in type 1 diabetes. These findings have raised a number of questions regarding how the remaining beta cells have escaped immune destruction, whether pools of 'sleeping' or dysfunctional beta cells could be rejuvenated and whether there is potential for new growth of beta cells. In this Review, we describe histological and in vivo evidence of persistent beta cells in type 1 diabetes and discuss the limitations of current methods to distinguish underlying beta cell mass in comparison with beta cell function. We highlight that evidence for new beta cell growth in humans many years from diagnosis is limited, and that this growth may be very minimal if at all present. We review recent contributions to the debate around beta cell abnormalities contributing to the pathogenesis of type 1 diabetes. We also discuss evidence for restoration of beta cell function, as opposed to mass, in recent-onset type 1 diabetes, but highlight the absence of data supporting functional recovery in the setting of long-duration diabetes. Finally, future areas of research are suggested to help resolve the source and phenotype of residual beta cells that persist in some, but not all, people with type 1 diabetes. Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin-Secreting Cells; Pancreas; Phenotype; Research Design | 2019 |
Better Diabetes Diagnoses in Sweden
The Swedish study Better Diabetes Diagnosis (BDD) has now been ongoing for ten years and detailed information and blood samples have been collected from more than 8000 children and adolescents with newly diagnosed diabetes. We have been able to demonstrate that by means of HLA diabetes antibodies and C-peptide the discrimination between type one and type 2 diabetes is improved. These analyses are therefore included in the clinical check-up for all children and adolescents in Sweden who are diagnosed with diabetes. Type 1 diabetes is by far the most prevalent type of diabetes among Swedish children and adolescents. Type 2 diabetes is still relatively rare in Sweden but it is urgent to obtain a correct diagnosis as the long-term prognosis depends on a prompt pharmacological treatment. Monogenic diabetes (MODY) is also important to identify early. We therefore recommend that sequencing of MODY genes should be performed if an individual with newly-diagnosed diabetes is auto-antibody negative and has an HLA pattern associated with low risk for type 1 diabetes. However, despite these analytical tools it can be difficult to make the correct diabetes diagnosis initially. It is therefore prudent to re-evaluate the diabetes diagnosis after one year. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnostic Tests, Routine; Histocompatibility Testing; Humans; Infant; Sweden | 2018 |
MicroRNAs: markers of β-cell stress and autoimmunity.
We discuss current knowledge about microRNAs (miRNAs) in type 1 diabetes (T1D), an autoimmune disease leading to severe loss of pancreatic β-cells. We describe: the role of cellular miRNAs in regulating immune functions and pathways impacting insulin secretion and β-cell survival; circulating miRNAs as disease biomarkers.. Studies examined miRNAs in experimental models and patients, including analysis of tissues from organ donors, peripheral blood cells, and circulating miRNAs in serum, plasma, and exosomes. Studies employed diverse designs and methodologies to detect miRNAs and measure their levels. Selected miRNAs have been linked to the regulation of key biological pathways and disease pathogenesis; several circulating miRNAs are associated with having T1D, islet autoimmunity, disease progression, and immune and metabolic functions, for example, C-peptide secretion, in multiple studies.. A growing literature reveals multiple roles of miRNAs in T1D, provide new clues into the regulation of disease mechanisms, and identify reproducible associations. Yet challenges remain, and the field will benefit from joint efforts to analyze results, compare methodologies, formally test the robustness of miRNA associations, and ultimately move towards validating robust miRNA biomarkers. Topics: Biomarkers; C-Peptide; Cell Survival; Diabetes Mellitus, Type 1; Exosomes; Humans; Insulin Secretion; Insulin-Secreting Cells; MicroRNAs | 2018 |
CTLA-4 +49 G/A, a functional T1D risk SNP, affects CTLA-4 level in Treg subsets and IA-2A positivity, but not beta-cell function.
To investigate whether CTLA-4 +49 G/A (rs231775), a tagSNP in Asian, is a functional T1D SNP, we genotyped this SNP with 1035 T1D patients and 2575 controls in Chinese Han population. And 1280 controls measured insulin release and sensitivity based on an oral glucose tolerance test; 283 newly diagnosed T1D patients assayed C-peptide level based on a mixed-meal tolerance test. 31 controls were analyzed for different T cell subsets by multi-color flow cytometry. Under additive model, we found that CTLA-4 +49 G/A was significantly associated with T1D (P = 2.82E-04, OR = 1.25, 95% CI: 1.12-1.41), which was further confirmed by meta-analysis (P = 1.19E-08, OR = 1.65, 95% CI: 1.38-1.96) in Chinese Han population. Although we did not find any association between this SNP and beta-cell function in either healthy individuals or newly diagnosed T1D patients, healthy individuals carrying GG/GA genotypes had lower CTLA-4 expression in naïve or activated CD4 Treg subsets (P = 0.0046 and 0.0317 respectively). A higher positive rate of IA-2A was observed among T1D patients with GG genotype compared with AA (OR = 0.51, 95% CI: 0.30-0.84, p = 0.008). Collectively, CTLA-4 +49 G/A reached a GWAS significant association with T1D risk in Chinese Han population, affects CTLA-4 expression in Treg subsets and subsequently humoral immunity in T1D patients. Topics: Adult; Asian People; C-Peptide; CTLA-4 Antigen; Diabetes Mellitus, Type 1; Female; Gene Expression Regulation; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Glucose Tolerance Test; Humans; Insulin; Male; Middle Aged; Polymorphism, Single Nucleotide; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Risk Factors; T-Lymphocytes, Regulatory; Young Adult | 2018 |
Serum biomarkers for diagnosis and prediction of type 1 diabetes.
Type 1 diabetes (T1D) culminates in the autoimmune destruction of the pancreatic βcells, leading to insufficient production of insulin and development of hyperglycemia. Serum biomarkers including a combination of glucose, glycated molecules, C-peptide, and autoantibodies have been well established for the diagnosis of T1D. However, these molecules often mark a late stage of the disease when ∼90% of the pancreatic insulin-producing β-cells have already been lost. With the prevalence of T1D increasing worldwide and because of the physical and psychological burden induced by this disease, there is a great need for prognostic biomarkers to predict T1D development or progression. This would allow us to identify individuals at high risk for early prevention and intervention. Therefore, considerable efforts have been dedicated to the understanding of disease etiology and the discovery of novel biomarkers in the last few decades. The advent of high-throughput and sensitive "-omics" technologies for the study of proteins, nucleic acids, and metabolites have allowed large scale profiling of protein expression and gene changes in T1D patients relative to disease-free controls. In this review, we briefly discuss the classical diagnostic biomarkers of T1D but mainly focus on the novel biomarkers that are identified as markers of β-cell destruction and screened with the use of state-of-the-art "-omics" technologies. Topics: Autoantibodies; Biomarkers; Blood Proteins; C-Peptide; Cytokines; Diabetes Mellitus, Type 1; Humans; Metabolomics; MicroRNAs | 2018 |
Implementing a Reference Measurement System for C-Peptide: Successes and Lessons Learned.
Assessment of endogenous insulin secretion by measuring C-peptide concentrations is widely accepted. Recent studies have shown that preservation of even small amounts of endogenous C-peptide production in patients with type 1 diabetes reduces risks for diabetic complications. Harmonization of C-peptide results will facilitate comparison of data from different research studies and later among clinical laboratory results at different sites using different assay methods.. This review provides an overview of the general process of harmonization and standardization and the challenges encountered with implementing a reference measurement system for C-peptide.. Efforts to harmonize C-peptide results are described, including those by the National Institute of Diabetes and Digestive and Kidney Diseases-led C-peptide Standardization Committee in the US, activities in Japan, efforts by the National Institute for Biological Standards and Control in the UK, as well as activities led by the Bureau International des Poids et Mesures and the National Metrology Institute in China. A traceability scheme is proposed along with the next steps for implementation. Suggestions are made for better collaboration to optimize the harmonization process for other measurands. Topics: C-Peptide; Clinical Laboratory Services; Diabetes Mellitus, Type 1; Humans; Observer Variation; Reference Standards | 2017 |
C-Peptide replacement therapy in type 1 diabetes: are we in the trough of disillusionment?
Type 1 diabetes is associated with such complications as blindness, kidney failure, and nerve damage. Replacing C-peptide, a hormone normally co-secreted with insulin, has been shown to reduce diabetes-related complications. Interestingly, after nearly 30 years of positive research results, C-peptide is still not being co-administered with insulin to diabetic patients. The following review discusses the potential of C-peptide as an auxilliary replacement therapy and why it's not currently being used as a therapeutic. Topics: Animals; Bibliometrics; C-Peptide; Clinical Trials as Topic; Diabetes Complications; Diabetes Mellitus, Type 1; Disease Models, Animal; History, 20th Century; History, 21st Century; Humans; Insulin; Insulin-Secreting Cells; Iron; Protein Binding; Serum Albumin; Zinc | 2017 |
Remission Phase in Paediatric Type 1 Diabetes: New Understanding and Emerging Biomarkers.
Type 1 diabetes (T1D) is a metabolic disease of unknown aetiology that results from the autoimmune destruction of the β-cells. Clinical onset with classic hyperglycaemic symptoms occurs much more frequently in children and young adults, when less than 30% of β-cells remain. Exogenous insulin administration is the only treatment for patients. However, due to glucose dysregulation, severe complications develop gradually. Recently, an increase in T1D incidence has been reported worldwide, especially in children. Shortly after diagnosis, T1D patients often experience partial remission called "honeymoon phase," which lasts a few months, with minor requirements of exogenous insulin. In this stage, the remaining β-cells are still able to produce enough insulin to reduce the administration of exogenous insulin. A recovery of immunological tolerance to β-cell autoantigens could explain the regeneration attempt in this remission phase. This mini-review focuses on the remission phase in childhood T1D. Understanding this period and finding those peripheral biomarkers that are signs of immunoregulation or islet regeneration could contribute to the identification of patients with a better glycaemic prognosis and a lower risk of secondary complications. This remission phase could be a good checkpoint for the administration of future immunotherapies. Topics: Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Remission Induction | 2017 |
C-peptide antioxidant adaptive pathways in β cells and diabetes.
In this review, we present findings that support autocrine cell protection by C-peptide in the context of clinical studies of type 1 diabetes (T1D), which universally measure C-peptide serum levels as a surrogate for β cell functional mass. Over the last decade, evidence has accumulated that supports models in which C-peptide, cosecreted with insulin by pancreatic β cells, acts on peripheral targets including the vascular endothelium to reduce oxidative stress and apoptosis subsequent to exposure to diabetic insults. In parallel, as assays have become more sensitive, C-peptide has been detected in the circulation of most subjects with T1D where higher C-peptide levels are associated with fewer and slower development of diabetic microvascular complications, consistent with antioxidant protection by C-peptide. Clinical trials investigating C-peptide-replacement therapy effects have demonstrated amelioration of T1D nephropathy and neuropathy. Recently, the antioxidant action of C-peptide was extended to the β cells secreting it, that is an autocrine mechanism. Autocrine protection has major implications for the treatment of diabetes because the more C-peptide secreted, the more protection provided to the same β cells resulting in a slower decay in β cell functional mass over the time course of disease. Why β cells evolved to cosecrete an antioxidant C-peptide hormone together with the glycaemia-lowering insulin hormone is explored in the context of proposed evolutionary advantages of physiologically transient oxidative stress and insulin resistance as an adaptation for survival through times of fuel scarcity. The importance of recognizing autocrine C-peptide protection of functional β cell mass in observational clinical studies, and its therapeutic implications in interventional C-peptide-replacement studies, will be discussed. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Disease Models, Animal; Endothelial Cells; Humans; Insulin Resistance; Insulin-Secreting Cells; Reactive Oxygen Species | 2017 |
C-peptide and diabetic kidney disease.
Kidney disease is a serious development in diabetes mellitus and poses an increasing clinical problem. Despite increasing incidence and prevalence of diabetic kidney disease, there have been no new therapies for this condition in the last 20 years. Mounting evidence supports a biological role for C-peptide, and findings from multiple studies now suggest that C-peptide may beneficially affect the disturbed metabolic and pathophysiological pathways leading to the development of diabetic nephropathy. Studies of C-peptide in animal models and in humans with type 1 diabetes all suggest a renoprotective effect for this peptide. In diabetic rodents, C-peptide reduces glomerular hyperfiltration and albuminuria. Cohort studies of diabetic patients with combined islet and kidney transplants suggest that maintained C-peptide secretion is protective of renal graft function. Further, in short-term studies of patients with type 1 diabetes, administration of C-peptide is also associated with a lowered hyperfiltration rate and reduced microalbuminuria. Thus, the available information suggests that type 1 diabetes should be regarded as a dual hormone deficiency disease and that clinical trials of C-peptide in diabetic nephropathy are both justified and urgently required. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Disease Models, Animal; Humans | 2017 |
Diabetes at the crossroads: relevance of disease classification to pathophysiology and treatment.
Diabetes is not a single homogeneous disease but composed of many diseases with hyperglycaemia as a common feature. Four factors have, historically, been used to identify this diversity: the age at onset; the severity of the disease, i.e. degree of loss of beta cell function; the degree of insulin resistance and the presence of diabetes-associated autoantibodies. Our broad understanding of the distinction between the two major types, type 1 diabetes mellitus and type 2 diabetes mellitus, are based on these factors, but it has become apparent that they do not precisely capture the different disease forms. Indeed, both major types of diabetes have common features, encapsulated by adult-onset autoimmune diabetes and maturity-onset diabetes of the young. As a result, there has been a repositioning of our understanding of diabetes. In this review, drawing on recent literature, we discuss the evidence that autoimmune type 1 diabetes has a broad clinical phenotype with diverse therapeutic options, while the term non-autoimmune type 2 diabetes obscures the optimal management strategy because it encompasses substantial heterogeneity. Underlying these developments is a general progression towards precision medicine with the need for precise patient characterisation, currently based on clinical phenotypes but in future augmented by laboratory-based tests. Topics: Age Factors; Alleles; Autoantibodies; Autoimmunity; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Genotype; Humans; Hyperglycemia; Insulin; Insulin Resistance; Phenotype | 2016 |
Revisiting multiple models of progression of β-cell loss of function in type 1 diabetes: Significance for prevention and cure.
Type 1 diabetes (T1D) results from a chronic autoimmune process that leads to β-cell destruction and exogenous insulin dependence. The natural history of T1D proposed by Eisenbarth suggested six relatively independent stages over the course of the entire disease process, which was considered to be linear and chronic. Based on this classical theory, immunotherapies aim to prevent or reverse all these periods of β-cell loss. Over the past 30 years, much novel information about the pathogenesis of T1D proved that there are complex metabolic changes occurring throughout the entire disease process. Therefore, new possible models for the natural history of the disease have been proposed; these models, in turn, may help facilitate fresh avenues for the prevention and cure of T1D. Herein, we briefly review recent findings in this field of research, with the aim of providing a better theoretical basis for clinical practice. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Genetic Predisposition to Disease; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Models, Biological; Time Factors | 2016 |
The clinical potential of low-level C-peptide secretion.
In all forms of diabetes, especially so in Type 1 diabetes (T1D), beta cell function is crucial for the course. The interest for residual beta cell function has been meagre, but increased in recent years with interventions to preserve function. Areas covered: Importance and clinical use of C-peptide in Type 1 diabetes. Data for this review were identified by searches of PubMed, and references from relevant articles using the search terms: "type 1 diabetes", "C-peptide", "beta cell function", "HbA1c", quality of life", "complications". Abstracts and reports from meetings were not included. Expert commentary: C-peptide may help to get a correct diagnosis, and it is of practical clinical value to know degree of residual insulin secretion to diminish the risk of severe hypoglycaemia and ketoacidosis. Evidence shows that even a quite reduced beta cell function may play an important role for quality of life, for metabolic balance/control, possibility to avoid complications and even for long-term survival. Furthermore, the evidence is increasing for C-peptide being a hormone per se. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells | 2016 |
Biomarkers of β-Cell Stress and Death in Type 1 Diabetes.
The hallmark of type 1 diabetes (T1D) is a decline in functional β-cell mass arising as a result of autoimmunity. Immunomodulatory interventions at disease onset have resulted in partial stabilization of β-cell function, but full recovery of insulin secretion has remained elusive. Revised efforts have focused on disease prevention through interventions administered at earlier disease stages. To support this paradigm, there is a parallel effort ongoing to identify circulating biomarkers that have the potential to identify stress and death of the islet β-cells. Whereas no definitive biomarker(s) have been fully validated, several approaches hold promise that T1D can be reliably identified in the pre-symptomatic phase, such that either β-cell preservation or immunomodulatory agents might be employed in at-risk populations. This review summarizes the most promising protein- and nucleic acid-based biomarkers discovered to date and reviews the context in which they have been studied. Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; DNA Methylation; Humans; Insulin-Secreting Cells; Proinsulin; RNA, Untranslated | 2016 |
C-peptide: new findings and therapeutic possibilities.
Much new information on C-peptide physiology has appeared during the past 20 years. It has been shown that C-peptide binds specifically to cell membranes, elicits intracellular signaling via G-protein and Ca2+ -dependent pathways, resulting in activation and increased expression of endothelial nitric oxide synthase, Na+, K+ -ATPase and several transcription factors of importance for anti-inflammatory, anti-oxidant and cell protective mechanisms. Studies in animal models of diabetes and early clinical trials in patients with type 1 diabetes demonstrate that C-peptide in replacement doses elicits beneficial effects on early stages of diabetes-induced functional and structural abnormalities of the peripheral nerves, the kidneys and the retina. Much remains to be learned about C-peptide's mechanism of action and long-term clinical trials in type 1 diabetes subjects will be required to determine C-peptide's clinical utility. Nevertheless, even a cautious evaluation of the available evidence presents the picture of a bioactive endogenous peptide with therapeutic potential. Topics: Animals; Anti-Inflammatory Agents; C-Peptide; Cell Membrane; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Humans; Male; Nitric Oxide Synthase Type III; Signal Transduction | 2015 |
The development, validation, and utility of the Diabetes Prevention Trial-Type 1 Risk Score (DPTRS).
This report details the development, validation, and utility of the Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score (DPTRS) for type 1 diabetes (T1D). Proportional hazards regression was used to develop the DPTRS model which includes the glucose and C-peptide sums from oral glucose tolerance tests at 30, 60, 90, and 120 min, the log fasting C-peptide, age, and the log BMI. The DPTRS was externally validated in the TrialNet Natural History Study cohort (TNNHS). In a study of the application of the DPTRS, the findings showed that it could be used to identify normoglycemic individuals who were at a similar risk for T1D as those with dysglycemia. The DPTRS could also be used to identify lower risk dysglycemic individuals. Risk estimates of individuals deemed to be at higher risk according to DPTRS values did not differ significantly between the DPT-1 and the TNNHS; whereas, the risk estimates for those with dysglycemia were significantly higher in DPT-1. Individuals with very high DPTRS values were found to be at such marked risk for T1D that they could reasonably be considered to be in a pre-diabetic state. The findings indicate that the DPTRS has utility in T1D prevention trials and for identifying pre-diabetic individuals. Topics: Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Prediabetic State; Risk Factors | 2015 |
[The clinical utility of C-peptide measurement in diabetology].
C-peptide is produced in equal amounts to insulin and is the best measure of endogenous insulin secretion in patients with diabetes. Measurement of insulin secretion using C-peptide can be helpful in clinical practice: differences in insulin secretion are fundamental to different requirements in the treatment of diabetes. An important clinical role of C-peptide is differentiating between type 1 and type 2 diabetes. Low basal C-peptide can be considered as criterion for transferring the patients, initially diagnosed as type 2 diabetes, in the type 1 diabetes group. C-peptide level may be a good predictor of the clinical partial remission during the first year of type 1 diabetes. Latent autoimmune diabetes in adults (LADA) is a special form of diabetes that is clinically similar to type 2 diabetes but with positivity for pancreatic autoantibodies and lower C-peptide levels. The measurement of C-peptide level and of immunological markers may represent important additional tools for establishing the correct diagnosis. The natural course of these patients shows that C-peptide will decrease with time in parallel with the curve for C-peptide in classical type 1 diabetic patients. Persistence of C-peptide is an important clinical feature of MODY. It is particularly important to identify these patients as they are commonly misdiagnosed as type 1 diabetes and treated with insulin, C-peptide can be used to assist in patient selection for islet cell transplantation and post-transplant monitoring. High uncorrected fasting C-peptid in the presence of hyperglycemia may suggest insulin resistance.. Peptyd C jest wytwarzany w ilości zależnej od ilości wytwarzanej insuliny i jest najlepszym wskaźnikiem do pomiaru endogennego wydzielania insuliny u chorych na cukrzycę. Pomiary wydzielania insuliny przy użyciu peptydu C mogą być pomocne w praktyce klinicznej do określania odpowiedniego leczenia cukrzycy. Peptyd C odgrywa ważną klinicznie rolę w różnicowaniu między typem 1 a typem 2 cukrzycy. Niskie podstawowe stężenie peptydu C może być kryterium zakwalifikowania pacjentów początkowo zdiagnozowanych jako chorych na cukrzycę typu 2 do grupy chorych na cukrzycę typu 1. Stężenie peptydu C to także dobry prognostyk częściowej remisji klinicznej w pierwszym roku zachorowania na cukrzycę typu 1. Utajona autoimmunologiczna cukrzyca u dorosłych (latent autoimmune diabetes in adults, LADA) jest szczególną formą tej choroby, która jest klinicznie podobna do cukrzycy typu 2, ale obecne są w niej autoprzeciwciała przeciwtrzustkowe. Pomiary stężenia peptydu C i markerów immunologicznych mogą stanowić ważne dodatkowe narzędzia do ustalenia prawidłowej diagnozy. Trwałość peptydu C jest ważną cechą kliniczną MODY (maturity onset diabetes of the young), ponieważ pacjenci są często błędnie diagnozowani jako chorzy na cukrzycę typu 1 i leczeni insuliną. Peptyd C może być również wykorzystany przy selekcji pacjentów do przeszczepu komórek wysp i do monitorowania po przeszczepie. Wysokie stężenie peptydu C, które nie ulega korekcie przy hiperglikemii, może sugerować insulinooporność. Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Insulin Secretion | 2015 |
Treatment of new onset type 1 diabetes with teplizumab: successes and pitfalls in development.
Type 1 diabetes is an organ-specific autoimmune disease, characterized by selective destruction of insulin-producing pancreatic β-cells by T-cell-mediated inflammation. Beginning with studies of cyclosporin A in the 1980s, but with more activity in the past decade, there have been a number of clinical trials to test whether immunotherapies can arrest the decline in C-peptide, which is associated with progression of type 1 diabetes leading to the metabolic instability that characterizes the disease. One of the most promising agents, teplizumab , is an FcR-nonbinding anti-CD3 monoclonal antibody that has been tested in Phase II - III clinical trials and was shown to preserve the C-peptide levels and reduce the need for exogenous insulin.. In this review, we discuss the recent update on clinical data obtained from trials of teplizumab in type 1 diabetes, the drug's postulated mechanism of action and the identification of responders to therapy. We highlight the results of recent trials as well as the lessons that have been learned from the clinical trials involving selection of end points and the inclusion of diverse study populations.. Teplizumab has been shown to preserve β cell function in patients; however, it does not represent a 'cure' for patients, and its efficacy does entail a significant advance in arresting the progression of the disease toward complete insulin deficiency and reliance on exogenous insulin. Topics: Animals; Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Drug Discovery; Humans; Hypoglycemic Agents; Immunotherapy; Insulin; Insulin-Secreting Cells; T-Lymphocytes; Treatment Outcome | 2014 |
Residual C-peptide in type 1 diabetes: what do we really know?
Connecting peptide, or C-peptide, is a protein that joins insulin's α and B chains in the proinsulin molecule. During insulin synthesis, C-peptide is cleaved from proinsulin and secreted in an equimolar concentration to insulin from the β cells. Because C-peptide experiences little first-pass clearance by the liver, and because levels are not affected by exogenous insulin administration, it may be used as a marker of endogenous insulin production and a reflection of β-cell function. Residual β-cell function, as measured by C-peptide in those with type 1 diabetes (T1D), has repeatedly been demonstrated to be clinically important. The Eisenbarth model of type 1 diabetes postulated immune-mediated linear loss of β cells, with clinical diagnosis occurring when there was insufficient insulin secretion to meet glycemic demand. Moreover, the model also implied that all individuals with T1D rapidly and inevitably progressed to absolute insulin deficiency. Correspondingly, it was assumed that most people with longstanding T1D would show little to no residual C-peptide secretion. While more than a quarter century of data confirms that this model remains largely true and appropriately serves as the basis for prevention studies, accumulating evidence suggests that the natural history of β-cell function before, during and after diagnosis is more complex. In this review, we discuss the clinical benefits of residual insulin secretion and present recent data about the natural history of insulin secretion in those with, or at risk for T1D. Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin-Secreting Cells; Prognosis; Treatment Outcome | 2014 |
C-peptide replacement therapy as an emerging strategy for preventing diabetic vasculopathy.
Lack of C-peptide, along with insulin, is the main feature of Type 1 diabetes mellitus (DM) and is also observed in progressive β-cell loss in later stage of Type 2 DM. Therapeutic approaches to hyperglycaemic control have been ineffective in preventing diabetic vasculopathy, and alternative therapeutic strategies are necessary to target both hyperglycaemia and diabetic complications. End-stage organ failure in DM seems to develop primarily due to vascular dysfunction and damage, leading to two types of organ-specific diseases, such as micro- and macrovascular complications. Numerous studies in diabetic patients and animals demonstrate that C-peptide treatment alone or in combination with insulin has physiological functions and might be beneficial in preventing diabetic complications. Current evidence suggests that C-peptide replacement therapy might prevent and ameliorate diabetic vasculopathy and organ-specific complications through conservation of vascular function, as well as prevention of endothelial cell death, microvascular permeability, vascular inflammation, and neointima formation. In this review, we describe recent advances on the beneficial role of C-peptide replacement therapy for preventing diabetic complications, such as retinopathy, nephropathy, neuropathy, impaired wound healing, and inflammation, and further discuss potential beneficial effects of combined C-peptide and insulin supplement therapy to control hyperglycaemia and to prevent organ-specific complications. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Humans; Hypoglycemic Agents; Signal Transduction; Treatment Outcome | 2014 |
The clinical utility of C-peptide measurement in the care of patients with diabetes.
C-peptide is produced in equal amounts to insulin and is the best measure of endogenous insulin secretion in patients with diabetes. Measurement of insulin secretion using C-peptide can be helpful in clinical practice: differences in insulin secretion are fundamental to the different treatment requirements of Type 1 and Type 2 diabetes. This article reviews the use of C-peptide measurement in the clinical management of patients with diabetes, including the interpretation and choice of C-peptide test and its use to assist diabetes classification and choice of treatment. We provide recommendations for where C-peptide should be used, choice of test and interpretation of results. With the rising incidence of Type 2 diabetes in younger patients, the discovery of monogenic diabetes and development of new therapies aimed at preserving insulin secretion, the direct measurement of insulin secretion may be increasingly important. Advances in assays have made C-peptide measurement both more reliable and inexpensive. In addition, recent work has demonstrated that C-peptide is more stable in blood than previously suggested or can be reliably measured on a spot urine sample (urine C-peptide:creatinine ratio), facilitating measurement in routine clinical practice. The key current clinical role of C-peptide is to assist classification and management of insulin-treated patients. Utility is greatest after 3-5 years from diagnosis when persistence of substantial insulin secretion suggests Type 2 or monogenic diabetes. Absent C-peptide at any time confirms absolute insulin requirement and the appropriateness of Type 1 diabetes management strategies regardless of apparent aetiology. Topics: C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Insulin Resistance; Insulin Secretion; Prognosis | 2013 |
Can C-peptide mediated anti-inflammatory effects retard the development of microvascular complications of type 1 diabetes?
Hyperglycemia is considered to be the major cause of microvascular complications of diabetes. Growing evidence highlights the importance of hyperglycemia-mediated inflammation in the initiation and progression of microvascular complications in type 1 diabetes. We hypothesize that lack of proinsulin C-peptide and lack of its anti-inflammatory properties contribute to the development of microvascular complications. Evidence gathered over the past 20 years shows that C-peptide is a biologically active peptide in its own right. It has been shown to reduce formation of reactive oxygen species and nuclear factor-κB activation induced by hyperglycemia, resulting in inhibition of cytokine, chemokine and cell adhesion molecule formation as well as reduced apoptotic activity. In addition, C-peptide stimulates and induces the expression of both Na⁺, K⁺-ATPase and endothelial nitric oxide synthase. Animal studies and small-scale clinical trials in type 1 diabetes patients suggest that C-peptide replacement combined with regular insulin therapy exerts beneficial effects on kidney and nerve dysfunction. Further clinical trials in patients with microvascular complications including measurements of inflammatory markers are warranted to explore the clinical significance of the aforementioned, previously unrecognized, C-peptide effects. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Endothelium, Vascular; Humans; Microvessels | 2013 |
Biomarkers for immune intervention trials in type 1 diabetes.
After many efforts to improve and standardize assays for detecting immune biomarkers in type 1 diabetes (T1D), methods to identify and monitor such correlates of insulitis are coming of age. The ultimate goal is to use these correlates to predict disease progression before onset and regression following therapeutic intervention, which would allow performing smaller and shorter pilot clinical trials with earlier endpoints than those offered by preserved β-cell function or improved glycemic control. Here, too, progress has been made. With the emerging insight that T1D represents a heterogeneous disease, the next challenge is to define patient subpopulations that qualify for personalized medicine or that should be enrolled for immune intervention, to maximize clinical benefit and decrease collateral damage by ineffective or even adverse immune therapeutics. This review discusses the current state of the art, setting the stage for future efforts to monitor disease heterogeneity, progression and therapeutic intervention in T1D. Topics: Autoantibodies; Biomarkers; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Disease Progression; Humans; Hypoglycemic Agents; Immunotherapy; Insulin; Islets of Langerhans Transplantation; T-Lymphocytes | 2013 |
Clinical application of regulatory T cells in type 1 diabetes.
Regulatory T cells (Tregs) are responsible for the maintenance of peripheral tolerance. Animal studies have shown that administration of Tregs can prevent type 1 diabetes (DM1). Several clinical trials attempted to induce Tregs with various agents, and thus provide long-term tolerance of β cells in DM1. Nevertheless, most of these studies have focused on clinical parameters (e.g. C-peptide) and not Treg numbers nor their function after treatment. Therefore, it is not possible to conclude if the majority of these therapies failed because the drugs did not induce Tregs, or if they failed despite Treg expansion. The current knowledge regarding Tregs, along with our experience in Treg therapy of patients with graft versus host disease, prompted us to use ex vivo expanded Tregs in 10 children with recent-onset DM1. No adverse effects in the treated individuals were observed. There was a significant increase in Treg number in peripheral blood immediately after the treatment administration, while the first clinical differences between treated and control patients were observed 4 months after Treg injection. Treated individuals had higher C-peptide levels and lower insulin requirements than non-treated children. Eleven months after diagnosis of DM1, there are still 2 individuals who are independent of exogenous insulin. These results indicate that autologous Tregs are a safe and well-tolerated therapy in children with DM1, which can inhibit or delay the destruction of pancreatic β cells. Additionally, Tregs can be a useful tool for local protection of transplanted pancreatic islets. Isolation and expansion of antigen-specific Tregs is one of the directions for future studies on cellular therapy of DM1. Topics: Adult; C-Peptide; Cell- and Tissue-Based Therapy; Chaperonin 60; Child; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Interleukin-2; Peptide Fragments; Sirolimus; T-Lymphocytes, Regulatory | 2013 |
GLP-1 agonists in type 1 diabetes.
Despite years of research in the field of type 1 diabetes, patients with the disease remain without a therapeutic agent that can alter the underlying immune response in a clinically beneficial way. Glucagon-like peptide 1 agonist therapies have shown some promising effects in terms of positively affecting overall beta cell health and increasing beta cell mass, primarily in mouse models. The three agents of this class currently available for patients with type 2 diabetes have shown beneficial clinical effects on glucose control in this patient population. The purpose of this article is to review the preclinical and clinical data of these agents to date with a focus on the potential immunological and clinical benefits these drugs may have on patients with type 1 diabetes. Topics: Animals; Biomarkers; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Exenatide; Glucagon-Like Peptide 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Liraglutide; Peptides; Venoms | 2013 |
[C-peptide physiological effects].
In the recent years there were numerous evidences that C-peptide, which was previously considered as a product of insulin biosynthesis, is one of the key regulators of physiological processes. C-peptide via heterotrimeric G(i/o) protein-coupled receptors activates a wide range of intracellular effector proteins and transcription factors and, thus, controls the inflammatory and neurotrophic processes, pain sensitivity, cognitive function, macro- and microcirculation, glomerular filtration. These effects of C-peptide are mainly expressed in its absolute or relative deficiency occurred in type 1 diabetes mellitus and they are less pronounced when the level of C-peptide is close to normal. Replacement therapy with C-peptide prevents many complications of type 1 diabetes, such as atherosclerosis, diabetic peripheral neuropathy, and nephropathy. C-peptide interacts with the insulin hexamer complexes and induces their dissociation and, as a result, regulates the functional activity of the insulin signaling system. At the same time, C-peptide at the concentrations above physiological may demonstrate pro-inflammatory effects on the endothelial cells and cause atherosclerotic changes in the vessels, which should be considered in the study of pathogenic mechanisms of complications of type 2 diabetes mellitus, where the level of C peptide is increased, as well as in the development of approaches for C-peptide application in clinic. This review is devoted contemporary achievements and unsolved problems in the study of C-peptide, as an important regulator of physiological and biochemical processes. Topics: C-Peptide; Cell Communication; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Endothelial Cells; Humans; Inflammation; Insulin; Microcirculation; Pain; Signal Transduction | 2013 |
[C-peptide structure, functions and molecular mechanisms of action].
C-peptide, which is formed during the biosynthesis of insulin, has long been considered as a biologically inactive substance. However in the recent years there is convincing evidence that the deficit of C-peptide in type 1 diabetes mellitus (DM) or its excess in DM2 lead to the development of disorders in the cardiovascular, nervous, excretory, and other systems of organism. It is shown than C-peptide in the physiological concentrations has anti-inflammatory, immunomodulatory and neuroprotective effects, so that it and its synthetic analogs can be widely used to treat diabetic patients and to prevent DM complications diabetes. To effectively use C-peptide in medicine it is necessary to study its structural-functional organization and the molecular mechanisms of regulatory action of C-peptide on the fundamental cellular processes. It is established that C-peptide coupled with Gi/o protein-coupled receptors of the serpentine type regulates the functional activity of many intracellular signaling pathways, which include phospholipase Cbeta, different forms of protein kinase C, phosphatidylinositol 3-kinases and mitogen-activated protein kinases, endothelial NO-synthase, Na+/K+-ATPase, a wide range of transcription factors and nuclear receptors. C-peptide controls the stability of the insulin hexamer complexes, and, thus,affects on the activity of insulin and insulin-regulated signaling pathways. The present review analyse the current state of the problem of structural-functional organization of C-peptide and its mechanism of action on the intracellular signaling pathways, as well as the prospects for the use of C-peptide in the fundamental biology and clinical medicine. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Extracellular Signal-Regulated MAP Kinases; Humans; Phosphatidylinositol 3-Kinases; Phospholipase C beta; Receptors, G-Protein-Coupled; Signal Transduction; Structure-Activity Relationship | 2013 |
Anti-CD3 clinical trials in type 1 diabetes mellitus.
Two humanized, anti-CD3 mAbs with reduced FcR binding, teplizumab and otelixizumab, have been evaluated in over 1500 subjects, ages 7-45, with new and recently diagnosed T1D with a range of intravenous doses (3-48mg) and regimens (6-14 days, single or repeat courses). In general, studies that used adequate dosing demonstrated improvement in stimulated C-peptide responses and reduced need for exogenous insulin for two years and even longer after diagnosis. Drug treatment causes a transient reduction in circulating T cells, but the available data suggest that the mechanism of action may involve induction of regulatory mechanisms. The adverse effects of anti-CD3 treatment are infusion-related and transient. The studies have identified significant differences in efficacy among patient groups suggesting that a key aspect for development of this immune therapy is identification of the demographic, metabolic, and immunologic features that distinguish subjects who are most likely to show beneficial clinical responses. Topics: Adolescent; Adult; Age Factors; Antibodies, Monoclonal, Humanized; C-Peptide; CD3 Complex; Child; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Infusions, Intravenous; Insulin; Male; Middle Aged; Receptors, Fc; T-Lymphocytes | 2013 |
Persistent C-peptide: what does it mean?
The assumption that patients with an extended duration of type 1 diabetes mellitus (T1D) do not retain residual functional β cells and endogenous insulin production has recently been challenged. The purpose to this review is to highlight some of the key emerging evidence supporting residual insulin and C-peptide secretion in long-standing T1D.. Recent investigations conducted in a group of type 1 diabetics of long-term duration, characterized clinically and histologically, provided solid evidence to suggest that pancreatic β cells are still present even after 50 years in a majority of these individuals. These residual β cells can secrete insulin in a physiologically regulated manner. Several published reports showed promising effects of glucagon-like peptide 1 (GLP-1) agonists on the glycemic control and residual C-peptide production in long-term T1D, although prospective studies are needed to rule out the potential long-term adverse effects of these drugs.. C-peptide is no longer considered an irrelevant by-product of insulin biosynthesis. In-depth basic and translational investigations aimed at understanding the molecular immunology and the pathophysiology are needed to elucidate the mechanisms underlying the residual insulin and C-peptide production in long-term T1D. This may shed light on to the regenerative capacity of β cells, the genetic susceptibility of the mechanisms of resistance to β-cell destruction, and possibly identifying new therapeutic strategies for T1D. Studies evaluating the long-term effects of insulin secretogogue agents along with immune intervention hold promise for their use in future clinical trials for long-term T1D. Topics: C-Peptide; Diabetes Mellitus, Type 1; Glucagon-Like Peptide 1; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells | 2013 |
C-peptide: a molecule balancing insulin states in secretion and diabetes-associated depository conditions.
Gradually, the C-peptide part of proinsulin has evolved from being viewed upon as a side product of insulin synthesis and secretion to being considered as a bioactive peptide with endocrine functions. Independent of these, its biophysical properties and peptide interactions point to still further roles of C-peptide, in particular regarding possible links to diabetes-related protein aggregations. Insulin, which can deposit at the injection sites in the treatment of diabetes, and islet amyloid polypeptide (IAPP), which can form amyloid fibrils in the islets of Langerhans in diabetes type 2, are kept nonaggregated by charge-based interactions with C-peptide at defined stoichiometries. It is possible that the conformational stabilization of insulin and IAPP by C-peptide may also counterbalance their aggregational tendencies at the high peptide concentrations in the pancreatic β-cell secretory granules. The concentration imbalances of C-peptide, insulin, and IAPP from the hyperpeptidism early in T2DM patients and the insulin-only injections in T1DM patients may distort equilibria of these peptide interactions and promote protein aggregation. Additionally, the chaperone-like actions of C-peptide may increase bioavailability of insulin supplements given to T1DM patients and prevent the formation of insulin deposits. Similarly, peptide interactions may influence depository tendencies in additional peptide systems. In short, biophysical studies are relevant to establish all roles of peptide imbalances in T1DM and T2DM and associated depository diseases. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Insulin Secretion; Islet Amyloid Polypeptide; Molecular Chaperones | 2013 |
[Type LADA diabetes--interrogation points].
Type LADA diabetes is a form of autoimmune-mediated diabetes in adults. The progression of beta-cell failure is slower than in childhood type 1 diabetes. Patients with LADA present with more preserved beta cell function than those with classic type l diabetes. The diagnosis of LADA according to Immunology Diabetes Society is based on three features: age over 35 years, the presence at least one of four circulating autoantibodies to pancreatic islet cell antigens and lack of requirement for insulin at least 6 month after diagnosis. The level of C-peptide secretion after stimulation with intravenous glucagon administration helped to diagnosis. The optimal treatment of latent autoimmune diabetes in adults (LADA) is not established. Consider that early insulin treatment would result in better preservation of beta-cell function and metabolic control. Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Disease Progression; Glucagon; Humans; Insulin; Islets of Langerhans | 2013 |
Determination of C-peptide in children: when is it useful?
Diabetes results from insulin deficiency but despite this endogenous insulin secretion is infrequently measured. C-peptide is not present in synthetic insulin so it's presence indicates endogenous secretion. One of the key roles for measuring C-peptide in childhood is to assist in the diagnosis of diabetes subtypes, which in turn determines appropriate management. It is also useful in Type 1 diabetes to monitor disease course, both in clinical practice and in trials following intervention with disease modifying agents. Measuring C-peptide routinely in Type 1 diabetes provides valuable information to the patient and clinician about glucose variability, risk of hypoglycemia and ketoacidosis. Newer more practical methods of C-peptide determination are now available to allow assessment of endogenous insulin secretion in routine clinical practice. We review the physiology of insulin secretion, the essential roles and methods for C-peptide determination in blood and in urine. Topics: Adolescent; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Proinsulin | 2013 |
DiaPep277® and immune intervention for treatment of type 1 diabetes.
Type 1 diabetes is a chronic immune-mediated disease resulting in destruction of insulin-producing β-cells. Several studies have been performed aiming to halt disease progression after diagnosis; to reduce the increased diabetes risk in islet-autoantibody positive subjects; and to prevent the onset of β-cell autoimmunity in subjects genetically at risk but without autoantibodies. Whereas secondary prevention trials failed, trials in newly diagnosed patients have shown partial success in preserving C-peptide. These studies target T-cells and inflammation and make use of antigen-specific immune modulation or stem cell approaches. However, thus far no immune-based therapeutic regimen has cured type 1 diabetes after its clinical onset or has stabilized the decline of C-peptide to achieve the status of an approved drug. This review summarizes immune intervention trials and the current knowledge of DiaPep277® peptide as a form of immune intervention in type 1 diabetes. Topics: Autoantibodies; Autoimmunity; C-Peptide; Chaperonin 60; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Hypoglycemic Agents; Immunotherapy; Islets of Langerhans; Peptide Fragments; T-Lymphocytes; Treatment Outcome | 2013 |
Clinical optimization of antigen specific modulation of type 1 diabetes with the plasmid DNA platform.
Some clinical trials in humans have aimed at modulation of type 1 diabetes (T1D) via alteration of the immune response to putative islet cell antigens, particularly proinsulin and insulin, glutamic acid decarboxylase and the peptide, DiaPep 277, derived from heat shock protein 60. The focus here is on development of a specially engineered DNA plasmid encoding proinsulin to treat T1D. The plasmid is engineered to turn off adaptive immunity to proinsulin. This approach yielded exciting results in a randomized placebo controlled trial in 80 adult patients with T1D. The implications of this trial are explored in regards to the potential for sparing inflammation in islets and thus allowing the functioning beta cells to recover and produce more insulin. Strategies to further strengthen the effects seen thus far with the tolerizing DNA plasmid to proinsulin will be elucidated. The DNA platform affords an opportunity for easy modifications. In addition standard exploration of dose levels, route of administration and frequency of dose are practical. Optimization of the effects seen to date on C-peptide and on depletion of proinsulin specific CD8 T cells are feasible, with expected concomitant improvement in other parameters like hemoglobin A1c and reduction in insulin usage. T1D is one of the few autoimmune conditions where antigen specific therapy can be achieved, provided the approach is tested intelligently. Tolerizing DNA vaccines to proinsulin and other islet cell autoantigens is a worthy pursuit to potentially treat, prevent and to perhaps even 'cure' or 'prevent' type 1 diabetes. Topics: Adaptive Immunity; Autoantigens; C-Peptide; CD8-Positive T-Lymphocytes; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Immunomodulation; Islets of Langerhans; Plasmids; Proinsulin; Vaccines, DNA | 2013 |
Potential role of non-insulin adjunct therapy in Type 1 diabetes.
Despite improvements in the pharmacodynamics of injectable insulin and better insulin delivery systems, glucose control remains suboptimal in the majority of individuals with Type 1 diabetes. Profound defects in the physiological processes that normally maintain glucose homeostasis contribute to the difficulty in achieving glycaemic targets. Non-insulin-based adjunct treatments offer a potential means of complementing intensive insulin therapy in Type 1 diabetes through addressing some of the physiological disturbances that result from endogenous β-cell destruction, particularly through preservation of β-cell mass and prevention of apoptosis, and suppression of α-cell glucagon release in the postprandial state. The former approach applies most readily to newly diagnosed C-peptide-positive Type 1 diabetes, while the latter to established C-peptide-negative Type 1 diabetes. This review focuses primarily on the clinical trial data available on the use of non-insulin-based therapies in longer-duration Type 1 diabetes. We conclude that metformin may prove useful in macrovascular disease reduction, while pramlintide, glucagon-like peptide-1 agonists, dipeptidyl peptidase-4 inhibitors and leptin co-therapies may reduce HbA(1c) , glucose variability, postprandial glucose excursions and body weight. These early studies are encouraging and offer novel and potentially very effective approaches to the treatment of Type 1 diabetes, but the evidence is largely restricted to small, often uncontrolled trials. As such, these therapies cannot be currently recommended for routine clinical practice. There is a clear need to support large, multi-centre randomized controlled trials designed to establish whether adjunct insulin therapy has a place in the modern management of Type 1 diabetes. Topics: Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Dipeptidyl-Peptidase IV Inhibitors; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Islet Amyloid Polypeptide; Male; Metformin; Randomized Controlled Trials as Topic | 2013 |
Regulation of insulin synthesis and secretion and pancreatic Beta-cell dysfunction in diabetes.
Pancreatic β-cell dysfunction plays an important role in the pathogenesis of both type 1 and type 2 diabetes. Insulin, which is produced in β-cells, is a critical regulator of metabolism. Insulin is synthesized as preproinsulin and processed to proinsulin. Proinsulin is then converted to insulin and C-peptide and stored in secretary granules awaiting release on demand. Insulin synthesis is regulated at both the transcriptional and translational level. The cis-acting sequences within the 5' flanking region and trans-activators including paired box gene 6 (PAX6), pancreatic and duodenal homeobox- 1(PDX-1), MafA, and β-2/Neurogenic differentiation 1 (NeuroD1) regulate insulin transcription, while the stability of preproinsulin mRNA and its untranslated regions control protein translation. Insulin secretion involves a sequence of events in β-cells that lead to fusion of secretory granules with the plasma membrane. Insulin is secreted primarily in response to glucose, while other nutrients such as free fatty acids and amino acids can augment glucose-induced insulin secretion. In addition, various hormones, such as melatonin, estrogen, leptin, growth hormone, and glucagon like peptide-1 also regulate insulin secretion. Thus, the β-cell is a metabolic hub in the body, connecting nutrient metabolism and the endocrine system. Although an increase in intracellular [Ca2+] is the primary insulin secretary signal, cAMP signaling- dependent mechanisms are also critical in the regulation of insulin secretion. This article reviews current knowledge on how β-cells synthesize and secrete insulin. In addition, this review presents evidence that genetic and environmental factors can lead to hyperglycemia, dyslipidemia, inflammation, and autoimmunity, resulting in β-cell dysfunction, thereby triggering the pathogenesis of diabetes. Topics: Basic Helix-Loop-Helix Transcription Factors; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Eye Proteins; Female; Gene Expression Regulation; Homeodomain Proteins; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Maf Transcription Factors, Large; Male; Paired Box Transcription Factors; PAX6 Transcription Factor; Protein Precursors; Repressor Proteins; RNA, Messenger; Trans-Activators | 2013 |
The clinical potential of C-peptide replacement in type 1 diabetes.
Topics: Animals; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Protein Binding | 2012 |
[Pleiotropic action of proinsulin C-peptide].
Proinsulin C-peptide, released in equimolar amounts with insulin by pancreatic β cells, since its discovery in 1967 has been thought to be devoid of biological functions apart from correct insulin processing and formation of disulfide bonds between A and B chains. However, in the last two decades research has brought a substantial amount of data indicating a crucial role of C-peptide in regulating various processes in different types of cells and organs. C-peptide acts presumably via either G-protein-coupled receptor or directly inside the cell, after being internalized. However, a receptor binding this peptide has not been identified yet. This peptide ameliorates pathological changes induced by type 1 diabetes mellitus, including glomerular hyperfiltration, vessel endothelium inflammation and neuron demyelinization. In diabetic patients and diabetic animal models, C-peptide substitution in physiological doses improves the functional and structural properties of peripheral neurons and protects against hyperglycemia-induced apoptosis, promoting neuronal development, regeneration and cell survival. Moreover, it affects glycogen synthesis in skeletal muscles. In vitro C-peptide promotes disaggregation of insulin oligomers, thus enhancing its bioavailability and effects on metabolism. There are controversies concerning the biological action of C-peptide, particularly with respect to its effect on Na⁺/K⁺-ATPase activity. Surprisingly, the excess of circulating peptide associated with diabetes type 2 contributes to atherosclerosis development. In view of these observations, long-term, large-scale clinical investigations using C-peptide physiological doses need to be conducted in order to determine safety and health outcomes of long-term administration of C-peptide to diabetic patients. Topics: Animals; Apoptosis; Atherosclerosis; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Neuropathies; Disease Models, Animal; Glycogen; Humans; Hyperglycemia; Muscle, Skeletal; Peripheral Nervous System | 2012 |
SUITO index for evaluation of clinical islet transplantation.
The major endpoints for clinical islet transplantation for type 1 diabetes are insulin independence and reduction of hypoglycemic episodes. Both endpoints are influenced by patients' and physicians' preferences regarding the use of exogenous insulin. Therefore, development of an objective endpoint for assessing clinical islet transplantation is desirable. HOMA-beta score is useful in assessing functional β-cell mass. However, this score uses blood insulin levels that are influenced by exogenous insulin injection and therefore is not suitable for patients who receive exogenous insulin. For assessing functional β-cell mass for type 1 diabetic patients after islet transplantation, we created the Secretory Unit of Islet Transplant Objects (SUITO) index using fasting C-peptide and fasting glucose. The formula of the SUITO index is fasting C-peptide (ng/ml)/[fasting blood glucose − 63 (mg/dl)] × 1500. We demonstrated that, within 1 month of islet transplantation, an average SUITO index of >26 was an excellent predictor of achieving insulin independence. In addition, daily SUITO index scores correlated with a reduction of insulin dose and adversely correlated with blood glucose levels during an intravenous glucose tolerance test. Other important endpoints, reduction of hypoglycemic episodes and quality of life, also correlated with the SUITO index. Thus, the SUITO index is excellent for assessing important endpoints (insulin independence, reduction of hypoglycemia, improved quality of life) after allogeneic islet transplantation. Topics: Algorithms; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation | 2012 |
Immunologic and metabolic biomarkers of β-cell destruction in the diagnosis of type 1 diabetes.
Type 1 diabetes (T1D), also known as insulin-dependent diabetes mellitus, is a chronic disorder that results from autoimmune destruction of insulin-producing β cells in the islets of Langerhans within the pancreas ( Atkinson and Maclaren 1994). This disease becomes clinically apparent only after significant destruction of the β-cell mass, which reduces the ability to maintain glycemic control and metabolic function. In addition, it continues for years after clinical onset until, generally, there is complete destruction of insulin secretory capacity. Because prevention and therapy strategies are targeted to this pathologic process, it becomes imperative to have methods with which it can be monitored. This work discusses current research-based approaches to monitor the autoimmunity and metabolic function in T1D patients and their potential for widespread clinical application. Topics: Autoantibodies; Biomarkers; C-Peptide; Cell Proliferation; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Islets of Langerhans; Magnetic Resonance Imaging; Optical Imaging; Organ Size; Positron-Emission Tomography; Sensitivity and Specificity; T-Lymphocytes | 2012 |
Immune biomarkers in immunotherapeutic trials for type 1 diabetes: cui prodest?
Decades of research efforts aimed at upgrading type 1 diabetes (T1DM) treatment did not harvest much success besides improving insulin therapy, which remains the standard of care since 1922. Immunological strategies targeting autoimmune mechanisms, rather than their metabolic consequences, are highly demanded. A dealt of preclinical studies in animal models offered some promises, which were however not maintained once translated into human. All these immune intervention trials evaluated metabolic and clinical endpoints, namely C-peptide secretion, HbA(1c) and insulin requirements. While critical, we argue that these endpoints are insufficient and should be complemented with immune surrogate endpoints, i.e. biomarkers reflecting the immune modifications induced by such treatments. This is even more critical when clinical expectations are not met, in order to sort out the reasons of such failure, i.e. whether immune changes are not accomplished or whether, despite being accomplished, they are insufficient to translate into clinical benefits. Furthermore, these ancillary analyses may give precious indications to design further trials, i.e. to enroll patients with the best odds to respond to therapy and to follow-up their response. Topics: Animals; Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunotherapy; Insulin; Male; Mice; Models, Animal; Predictive Value of Tests; Prognosis; Reproducibility of Results | 2012 |
C-peptide and long-term complications of diabetes.
Topics: Animals; C-Peptide; Cell Membrane; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Endothelium, Vascular; Humans; Inflammation; Nitric Oxide; Regional Blood Flow; Signal Transduction | 2011 |
T cell recognition of autoantigens in human type 1 diabetes: clinical perspectives.
Type 1 diabetes (T1D) is an autoimmune disease driven by the activation of lymphocytes against pancreatic β-cells. Among β-cell autoantigens, preproinsulin has been ascribed a key role in the T1D process. The successive steps that control the activation of autoreactive lymphocytes have been extensively studied in animal models of T1D, but remains ill defined in man. In man, T lymphocytes, especially CD8(+) T cells, are predominant within insulitis. Developing T-cell assays in diabetes autoimmunity is, thus, a major challenge. It is expected to help defining autoantigens and epitopes that drive the disease process, to pinpoint key functional features of epitope-specific T lymphocytes along the natural history of diabetes and to pave the way towards therapeutic strategies to induce immune tolerance to β-cells. New T-cell technologies will allow defining autoreactive T-cell differentiation programs and characterizing autoimmune responses in comparison with physiologically appropriate immune responses. This may prove instrumental in the discovery of immune correlates of efficacy in clinical trials. Topics: Amino Acid Sequence; Animals; Autoantibodies; Autoantigens; Autoimmunity; C-Peptide; CD8-Positive T-Lymphocytes; Clinical Trials as Topic; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Epitopes, T-Lymphocyte; Glutamate Decarboxylase; HLA-D Antigens; Humans; Immune Tolerance; Insulin; Insulin-Secreting Cells; Lymphocyte Activation; Mice; Mice, Inbred NOD; Mice, Transgenic; Protein Precursors; T-Lymphocytes, Helper-Inducer | 2011 |
Fulminant type 1 diabetes--an important subtype in East Asia.
Fulminant type 1 diabetes is defined as a subtype of type 1 diabetes with a remarkably acute onset. A nationwide survey identified that this variant accounts for approximately 20% of acute-onset type 1 diabetic patients in Japan. Recent studies indicate that this is not a minor subtype in other East Asian countries. As genetic factors, we revealed association of HLA-DR-DQ, HLA-B and CTLA-4 to fulminant type 1 diabetes. As an environmental factor, viral infection would contribute to the development of this subtype. Cellular infiltration to islets was detected soon after the onset but not observed 1 month after the onset. Macrophages and T cells were the main components of the infiltrates. Enterovirus RNA and Toll-like receptor-3 expression, a signature of viral infection, was also observed. These findings suggest that viral infection in the susceptible individual might trigger anti-viral immune response and that pancreatic beta cells are rapidly destroyed through the accelerated immune reaction. Topics: Acute Disease; Adult; Aged; Asia, Eastern; Blood Glucose; C-Peptide; CTLA-4 Antigen; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Enterovirus Infections; Female; Glycated Hemoglobin; HLA-B Antigens; HLA-DRB1 Chains; Humans; Insulin-Secreting Cells; Japan; Male; Middle Aged; Virus Diseases | 2011 |
Successes and disappointments with clinical islet transplantation.
Transplantation of pancreatic islets is considered a therapeutic option for patients with type 1 diabetes mellitus who have life-threatening hypoglycaemic episodes. After the procedure, a decrease in the frequency and severity of hypoglycaemic episodes and sustained graft function as indicated by detectable levels of C-peptide can be seen in the majority of patients. However, true insulin independence, if achieved, usually lasts for at most a few years. Apart from the low insulin independence rates, reasons for concern regarding this procedure are the side effects of the immunosuppressive therapy, allo-immunization, and the high costs. Moreover, whether islet transplantation prevents the progression of diabetic micro- and macrovascular complications is largely unknown. Areas of current research include the development of less toxic immunosuppressive regimens, the control of the inflammatory reaction immediately after transplantation, the identification of the optimal anatomical site for islet infusion, and the possibility to encapsulate transplanted islets to protect them from the allo-immune response. At present, pancreatic islet transplantation is still an experimental procedure, which is only indicated for a highly selected group of type 1 diabetic patients with life-threatening hypoglycaemic episodes. Topics: Animals; Blood Glucose; C-Peptide; Cost-Benefit Analysis; Diabetes Complications; Diabetes Mellitus, Type 1; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Quality of Life; Treatment Outcome | 2010 |
C-peptide as a therapeutic tool in diabetic nephropathy.
Insulin is synthesised as a pro-hormone with an interconnecting C-peptide, cleaved during post-translational modification. This review discusses growing evidence which indicates that C-peptide is biologically active, benefiting microvascular complications associated with diabetes.. To explore the renoprotective role of C-peptide in diabetic nephropathy (DN), we reviewed the literature using PubMed for English language articles that contained key words related to C-peptide, kidney and DN.. Numerous studies have demonstrated that C-peptide ameliorates a number of the structural and functional renal disturbances associated with uncontrolled hyperglycaemia in human and animal models of type 1 diabetes mellitus that lead to the development and progression of nephropathy, including abrogation of glomerular hyperfiltration, reduced microalbuminuria, decreased mesangial expansion and increased endothelial nitric oxide synthase levels. The in vitro exposure of kidney proximal tubular cells to physiological concentrations of C-peptide activates extracellular signal-regulated kinase, phosphatidylinositol 3-kinase, protein kinase C, elevates intracellular calcium, and stimulates transcription factors NF-kappaB and peroxisome proliferator-activated receptor-gamma.. Burgeoning studies suggest that C-peptide is more than merely a link between the A and B chains of the proinsulin molecule and represents a future therapeutic tool in reducing complications of DN. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Disease Progression; Fibrosis; Humans; Hyperglycemia; Models, Biological; NF-kappa B; Nitric Oxide Synthase Type III; Phosphatidylinositol 3-Kinases; Protein Kinase C; Sodium-Potassium-Exchanging ATPase | 2010 |
Use of technology to potentially preserve C-Peptide in type 1 diabetes mellitus.
Preservation of residual beta-cell function has become a new therapeutic goal in type 1 diabetes (T1DM). A mathematical equation of insulin dose and A1C allows estimating residual beta-cell function without C-peptide measurement. Slowing the decline of C-peptide levels has been established as a surrogate endpoint for different pharmacological treatments preserving betacell mass and beta-cell function in newly onset patients. Age at onset proves to be crucial, both for predicting the rate of decline in beta-cell function and the overall duration of this so-called remission phase. Glycemic control has a role in defining the remission phase as well as in influencing the decline of residual function through glucose toxicity. Recent evidence points to the usefulness of new technologies like insulin pumps and continuous glucose monitors (CGM) for decreasing glycemic variability. This may preserve C-peptide and improve outcomes both with and without additional immunomodulatory therapy at the onset of T1DM. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin Infusion Systems; Insulin-Secreting Cells; Monitoring, Ambulatory; Technology | 2010 |
[C-peptide: a by-product of insulin biosynthesis or an active peptide hormone?].
Topics: Albuminuria; Animals; Biomarkers; C-Peptide; Calmodulin; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glomerular Filtration Rate; Humans; Insulin; Insulin-Secreting Cells; Metabolic Syndrome; Receptors, G-Protein-Coupled; Sodium-Potassium-Exchanging ATPase | 2009 |
Cellular and physiological effects of C-peptide.
In recent years, accumulating evidence indicates a biological function for proinsulin C-peptide. These results challenge the traditional view that C-peptide is essentially inert and only useful as a surrogate marker of insulin release. Accordingly, it is now clear that C-peptide binds with high affinity to cell membranes, probably to a pertussis-toxin-sensitive G-protein-coupled receptor. Subsequently, multiple signalling pathways are potently and dose-dependently activated in multiple cell types by C-peptide with the resulting activation of gene transcription and altered cell phenotype. In diabetic animals and Type 1 diabetic patients, short-term studies indicate that C-peptide also enhances glucose disposal and metabolic control. Furthermore, results derived from animal models and clinical studies in Type 1 diabetic patients suggest a salutary effect of C-peptide in the prevention and amelioration of diabetic nephropathy and neuropathy. Therefore a picture of Type 1 diabetes as a dual-hormone-deficiency disease is developing, suggesting that the replacement of C-peptide alongside insulin should be considered in its management. Topics: Animals; Blood Glucose; C-Peptide; Cell Membrane; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Neuropathies; Humans; Mice | 2009 |
C-peptide in the natural history of type 1 diabetes.
Type 1 diabetes is diagnosed when the patient's endogenous insulin secretion decreases to a level which results in hyperglycemia. After diagnosis, insulin secretion continues to decline. As a reference for clinical trials trying to preserve endogenous beta-cell function in patients with recently diagnosed type 1 diabetes, in this short review I attempt to summarize the natural history of endogenous beta-cell function after the diagnosis of type 1 diabetes. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells | 2009 |
Immune modulation in type 1 diabetes mellitus using DiaPep277: a short review and update of recent clinical trial results.
In type 1 diabetes mellitus, autoimmune T-cells mount an attack on insulin producing beta-cells eventually causing hyperglycemia. It is hypothesized, that to prevent and treat this disease, one must interfere with the autoimmune process. To avoid hazardous side effects, this intervention should not cause a global immune suppression but immune modulation. DiaPep277 (peptide 277) is a 24 amino acid peptide derived from positions 437-460 in HSP60. It has recently been shown to have an immune modulatory effect on diabetogenic T cells in animal models of diabetes. It has also been recently implicated as a possible auto-antigen in type 1 diabetes. Promising results in animal models led to phase 1 to 3 human clinical trials in patients with type 1 diabetes, the results of which are the focus of this review. A combined analysis of all the adult phase II studies revealed that DiaPep277 significantly inhibits the decline in stimulated C-peptide secretion (thus preserving endogenous insulin secretion). This effect was more pronounced in patients with a high beta-cell reserve at the start of the treatment. Furthermore, opposite trends in glycemic control of DiaPep277 treated patients where noted as opposed to placebo treated patients. The phase III study has began more than 2 years ago in 40 medical centers worldwide, and thus far recruited over 350 patients around the world. If DiaPep277 will prove to be efficacious, it will cause a paradigm shift in the treatment of type 1 diabetes, from treating the subsequent insulin deficiency to addressing the initial autoimmune process that is at the heart of the disease. Topics: Animals; Blood Glucose; C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Humans; Immunologic Factors; Insulin; Insulin Secretion; Insulin-Secreting Cells; Peptide Fragments; Peptides; T-Lymphocytes | 2009 |
Point: steady progress and current challenges in clinical islet transplantation.
Topics: C-Peptide; Cell Transplantation; Diabetes Complications; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Treatment Outcome | 2009 |
Challenges in developing endpoints for type 1 diabetes intervention studies.
Development of efficient and safe intervention strategies for preserving and/or restoring endogenous insulin production in type 1 diabetes has encountered a wide range of challenges, including lack of standardized trial protocols and of consensus on appropriate efficacy endpoints. For the greatest part, difficulties resided in choosing the most suitable assay(s) and parameter(s) to assess the beta-cell function. It is now an accepted approach to evaluate endogenous insulin secretion by measuring C-peptide levels (with highly sensitive and normalized measurement methods) in response to a physiologic stimulus (liquid mixed-meal) under standardized conditions. Preventive interventions mandate the identification of well-defined, reliable and validated mechanistic or immunological markers of efficacy that would correlate with (and predict) the clinical outcome. This has not been consistently achieved to date. However, it has been generally agreed that for preventive studies performed very early in the disease course (in subjects without signs of autoimmunity against beta-cells) development of two or more islet related autoantibodies could be employed as biomarkers of disease and thereafter, diagnostic criteria of diabetes serve as suitable endpoints.This report summarizes the conclusions of the D-Cure workshop of international experts held in Barcelona in April 2007 and the current recommendations and updates in the field. Topics: C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Endpoint Determination; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Organ Size | 2009 |
The role of immunomodulation therapy in autoimmune diabetes.
Type 1 diabetes (T1DM) is characterized by loss of virtually all endogenous insulin secretion. If residual insulin secretion is preserved, this will lead to improved metabolic balance, less acute and late complications, improved quality of life, and, in case of pronounced improvement of residual insulin secretion, complete remission and even cure of the disease. Immune suppression or immune modulation have been demonstrated as a proof of principle to stop/decrease the destructive process and thereby preserve beta-cell function. Several methods to save residual beta-cell function have been tried for more than three decades with little or no evidence of efficacy. Positive effects have been seen mainly in adult patients but have been minimal or absent in children with diabetes. Furthermore, the safety of these immune interventions and/or their benefit to risk relationships have not been found to justify clinical use. More specific immune modulation with anti-CD3 monoclonal antibodies has resulted in more encouraging postponement of C-peptide decline, but with frequent and serious adverse effects. Still more promising are the autoantigen therapies, of which glutamic acid decarboxylase (GAD) vaccination has shown significant preservation of residual insulin secretion in 10-18-year-old type 1 diabetes patients with recent onset. Efficacy was most impressive in the subgroup of patients with diabetes of short duration (<3 months). The treatment was simple, well tolerated, and showed no treatment-related adverse events. If these results can be confirmed, there is a realistic hope that GAD vaccination, perhaps in combination with vaccinations with other autoantigens and/or other therapies, will result in remission for some patients. The prospects of cure and prevention of T1DM will become less remote. Topics: Adolescent; Adult; Autoantibodies; Autoantigens; Blood Glucose; C-Peptide; CD3 Complex; Child; Child, Preschool; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Immunomodulation; Insulin; Insulin-Secreting Cells | 2009 |
C-Peptide effects on renal physiology and diabetes.
The C-peptide of proinsulin is important for the biosynthesis of insulin and has for a long time been considered to be biologically inert. Animal studies have shown that some of the renal effects of the C-peptide may in part be explained by its ability to stimulate the Na,K-ATPase activity. Precisely, the C-peptide reduces diabetes-induced glomerular hyperfiltration both in animals and humans, therefore, resulting in regression of fibrosis. The tubular function is also concerned as diabetic animals supplemented with C-peptide exhibit better renal function resulting in reduced urinary sodium waste and protein excretion together with the reduction of the diabetes-induced glomerular hyperfiltration. The tubular effectors of C-peptide were considered to be tubule transporters, but recent studies have shown that biochemical pathways involving cellular kinases and inflammatory pathways may also be important. The matter theory concerning the C-peptide effects is a metabolic one involving the effects of the C-peptide on lipidic metabolic status. This review concentrates on the most convincing data which indicate that the C-peptide is a biologically active hormone for renal physiology. Topics: Animals; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glomerular Filtration Rate; Humans; Inflammation; Kidney Glomerulus; Kidney Tubules; Lipid Metabolism; Signal Transduction; Sodium-Potassium-Exchanging ATPase | 2008 |
Role of C-Peptide in the regulation of microvascular blood flow.
During the recent years, the role of C-peptide, released from the pancreatic beta cell, in regulating microvascular blood flow, has received increasing attention. In type 1 diabetic patients, intravenous application of C-peptide in physiological concentrations was shown to increase microvascular blood flow, and to improve microvascular endothelial function and the endothelial release of NO. C-peptide was shown to impact microvascular blood flow by several interactive pathways, like stimulating Na(+)K(+)ATPase or the endothelial release of NO. There is increasing evidence, that in patients with declining beta cell function, the lack of C-peptide secretion might play a putative role in the development of microvascular blood flow abnormalities, which go beyond the effects of declining insulin secretion or increased blood glucose levels. Topics: Blood Flow Velocity; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Endothelium, Vascular; Erythrocyte Deformability; Humans; Microcirculation; Nitric Oxide | 2008 |
The islet autoantibody titres: their clinical relevance in latent autoimmune diabetes in adults (LADA) and the classification of diabetes mellitus.
Latent autoimmune diabetes in the adult (LADA) is a slowly progressive form of autoimmune diabetes, characterized by diabetes-associated autoantibody positivity. A recent hypothesis proposes that LADA consists of a heterogeneous population, wherein several subgroups can be identified based on their autoimmune status. A systematic review of the literature was carried out to appraise whether the clinical characteristics of LADA patients correlate with the titre and numbers of diabetes-associated autoantibodies. We found that the simultaneous presence of multiple autoantibodies and/or a high-titre anti-glutamic acid decarboxylase (GAD)--compared with single and low-titre autoantibody--is associated with an early age of onset, low fasting C-peptide values as a marker of reduced pancreatic B-cell function, a high predictive value for future insulin requirement, the presence of other autoimmune disorders, a low prevalence of markers of the metabolic syndrome including high body mass index, hypertension and dyslipidaemia, and a high prevalence of the genotype known to increase the risk of Type 1 diabetes. We propose a more continuous classification of diabetes mellitus, based on the finding that the clinical characteristics gradually change from classic Type 1 diabetes to LADA and finally to Type 2 diabetes. Future studies should focus on determining optimal cut-off points of anti-GAD for differentiating clinically relevant diabetes mellitus subgroups. Topics: Adult; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Islets of Langerhans; Male; Middle Aged | 2008 |
Is C-peptide replacement the missing link for successful treatment of neurological complications in type 1 diabetes?
In this review we will describe the interaction between insulin and C-peptide which enhances and attenuates insulin-signaling functions. We will describe how replenishment of C-peptide prevents and reverses the early metabolic abnormalities in type 1 diabetic polyneuropathy, such as Na(+)/K(+)-ATPase activity and endoneurial vascular NO release, resulting in prevention and reversal of early nerve dysfunction. The effects on expression of neurotrophic factors and their receptors, mediated by corrections of early gene responses and transcription factors, have downstream beneficial effects on cytoskeletal protein mRNAs and protein expression. Similar effects probably underlie corrections of cell adhesive molecules. The end-effects are prevention and reversal of myelinated and unmyelinated axonal degeneration, atrophy, and loss. Similarly, progressive degeneration of the node and paranode is prevented and repaired by C-peptide replacement with normalization of the molecular constituents of these functionally important structures. Cognitive dysfunction is now recognized as a complication of type 1 diabetes. Experimentally it is linked to impaired synaptic plasticity and eventually apoptotic neuronal loss caused by impaired insulin action and neurotrophic support. C-peptide replacement partially prevents hippocampal neuronal apoptosis and cognitive deficits. It is therefore becoming increasingly clear that C-peptide has major functions in supporting insulin action with a multitude of beneficial effects on diabetic polyneuropathy and primary diabetic encephalopathy in type 1 diabetes. Topics: Animals; Brain Diseases, Metabolic; C-Peptide; Cognition Disorders; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Gene Expression Regulation; Humans; Insulin; Signal Transduction | 2008 |
Effects of beta-cell rest on beta-cell function: a review of clinical and preclinical data.
Topics: Adult; C-Peptide; Child; Clinical Trials as Topic; Dendritic Cells; Diabetes Mellitus, Type 1; Glucose; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Models, Biological; Oxidative Stress | 2008 |
Effect of C-peptide on diabetic neuropathy in patients with type 1 diabetes.
Recent results indicate that proinsulin C-peptide, contrary to previous views, exerts important physiological effects and shows the characteristics of a bioactive peptide. Studies in type 1 diabetes, involving animal models as well as patients, demonstrate that C-peptide in replacement doses has the ability to improve peripheral nerve function and prevent or reverse the development of nerve structural abnormalities. Peripheral nerve function, as evaluated by determination of sensory nerve conduction velocity and quantitative sensory testing, is improved by C-peptide replacement in diabetes type 1 patients with early stage neuropathy. Similarly, autonomic nerve dysfunction is ameliorated following administration of C peptide for up to 3 months. As evaluated in animal models of type 1 diabetes, the improved nerve function is accompanied by reversal or prevention of nerve structural changes, and the mechanisms of action are related to the ability of C-peptide to correct diabetes-induced reductions in endoneurial blood flow and in Na+ K+-ATPase activity and modulation of neurotrophic factors. Combining the results demonstrates that C-peptide may be a possible new treatment of neuropathy in type 1 diabetes. Topics: Adult; C-Peptide; Controlled Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Humans | 2008 |
Intracellular signalling by C-peptide.
C-peptide, a cleavage product of the proinsulin molecule, has long been regarded as biologically inert, serving merely as a surrogate marker for insulin release. Recent findings demonstrate both a physiological and protective role of C-peptide when administered to individuals with type I diabetes. Data indicate that C-peptide appears to bind in nanomolar concentrations to a cell surface receptor which is most likely to be G-protein coupled. Binding of C-peptide initiates multiple cellular effects, evoking a rise in intracellular calcium, increased PI-3-kinase activity, stimulation of the Na(+)/K(+) ATPase, increased eNOS transcription, and activation of the MAPK signalling pathway. These cell signalling effects have been studied in multiple cell types from multiple tissues. Overall these observations raise the possibility that C-peptide may serve as a potential therapeutic agent for the treatment or prevention of long-term complications associated with diabetes. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Kidney Tubules; Mitogen-Activated Protein Kinase Kinases; Nitric Oxide Synthase Type III; Rats; Signal Transduction; Sodium-Potassium-Exchanging ATPase; Transcription, Genetic | 2008 |
The effects of C-peptide on type 1 diabetic polyneuropathies and encephalopathy in the BB/Wor-rat.
Diabetic polyneuropathy (DPN) occurs more frequently in type 1 diabetes resulting in a more severe DPN. The differences in DPN between the two types of diabetes are due to differences in the availability of insulin and C-peptide. Insulin and C-peptide provide gene regulatory effects on neurotrophic factors with effects on axonal cytoskeletal proteins and nerve fiber integrity. A significant abnormality in type 1 DPN is nodal degeneration. In the type 1 BB/Wor-rat, C-peptide replacement corrects metabolic abnormalities ameliorating the acute nerve conduction defect. It corrects abnormalities of neurotrophic factors and the expression of neuroskeletal proteins with improvements of axonal size and function. C-peptide corrects the expression of nodal adhesive molecules with prevention and repair of the functionally significant nodal degeneration. Cognitive dysfunction is a recognized complication of type 1 diabetes, and is associated with impaired neurotrophic support and apoptotic neuronal loss. C-peptide prevents hippocampal apoptosis and cognitive deficits. It is therefore clear that substitution of C-peptide in type 1 diabetes has a multitude of effects on DPN and cognitive dysfunction. Here the effects of C-peptide replenishment will be extensively described as they pertain to DPN and diabetic encephalopathy, underpinning its beneficial effects on neurological complications in type 1 diabetes. Topics: Animals; Brain Diseases; C-Peptide; Cognition Disorders; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Hyperalgesia; Rats; Rats, Inbred BB | 2008 |
[Latent autoimmune diabetes of adult or slim type 2 diabetes mellitus?].
The prevalence of latent autoimmune diabetes of the adult (LADA) varies according to the population studied, criteria used and antibodies analyzed. In a series of 256 patients > 25 years, we found that 26 (10.2%) were anti-GAD antibody (GADA) positive and 16 of them (6.3%) progressed without initial insulin requirement. Although controversy exists, the following diagnostic criteria for LADA are suggested: age between 25 and 65 years; absence of ketoacidosis or symptomatic hyperglycemia at diagnosis or immediately thereafter, without insulin requirement for 6-12 months; and presence of autoantibodies (especially GADA). Autoimmunity and insulin resistance coexist in LADA and the contribution of these factors seems to be reflected in GADA titers. A subgroup, which is phenotypically and in terms of insulin requirement similar to type 2 diabetic patients, seems to be better identified based on the presence of low GADA titers, especially when these antibodies are present alone. On the other hand, subjects with high GADA titers and multiple antibodies show a phenotype close to that of classical DM 1 and are at a higher risk of premature beta-cell failure. Compared to GADA-negative diabetics, patients with LADA present a higher prevalence of other autoantibodies (anti-TPO, anti-21-hydroxylase and antibodies associated with celiac disease) and a higher frequency of genotypes and haplotypes indicating a risk for DM 1. Patients with high GADA titers may benefit from early insulinization and avoiding the use of sulfonylureas, delaying beta-cell failure. In contrast, patients with low GADA titers do not seem to have any disadvantage when managed as type 2 diabetic patients (GADA negative). Topics: Adult; Aged; Aged, 80 and over; Autoantibodies; Autoimmunity; Biomarkers; Brazil; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Genetic Predisposition to Disease; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Middle Aged; Prevalence; Young Adult | 2008 |
[C-peptide residual secretion makes difference on type 1 diabetes management?].
Type 1 diabetes is a chronic disease characterized by progressive destruction of the pancreatic beta cells, what leads to insulin deficiency and hyperglycemia. However, a significant secretory function may persist for long periods in a few patients, what is clinically evident through the detection of serum C peptide. This phenomenon might reduce the risk of chronic complications, severe hypoglycemias and allow easier metabolic control. It is possible that these advantages are caused, at least partially, by C peptide itself, acting directly in its target tissues. Topics: Adolescent; Adult; Aged; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Chronic Disease; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Young Adult | 2008 |
Prediction of clinical outcome in islet allotransplantation.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Predictive Value of Tests; Transplantation, Homologous; Treatment Outcome | 2007 |
Interventions for latent autoimmune diabetes (LADA) in adults.
Latent autoimmune diabetes in Adults (LADA) is a slowly developing type 1 diabetes which presents as non-insulin dependent diabetes and progresses to insulin dependence. However, the best treatment strategy for LADA is unclear.. To compare interventions used for LADA.. Studies were obtained from searches of electronic databases (including MEDLINE, EMBASE), supplemented by hand searches, conference proceedings and consultation with experts.. Selection was in duplicate by two independent reviewers. RCT and controlled clinical trials evaluating interventions for LADA or type 2 diabetes with antibodies were included.. Two reviewers independently extracted data and assessed study quality. Studies were summarised in a descriptive manner.. Searches identified 8067 citations. Eight publications (seven studies) were included, involving 735 participants. All studies had high risk of bias. There were no data on use of metformin or glitazones alone. Rosiglitazone or sulphonylurea (SU) with insulin did not improve metabolic control significantly more than insulin alone. SU alone gave either poorer (one study, mean difference in HbA1c 2.8% (95% confidence interval (CI) 0.9 to 4.7) or equivalent metabolic control compared to insulin alone (two studies). There was evidence that SU caused earlier insulin dependence (insulin treated at two years: 60% (SU) and 5% (conventional care) (P < 0.001); classified insulin dependent: 64% (SU) and 12.5% (insulin group) (P = 0.007)). No interventions influenced fasting C-peptide, but insulin maintained stimulated C-peptide better than SU (one study, mean difference 7.7 ng/ml (95% CI 2.9 to 12.5) and insulin with rosiglitazone was superior to insulin alone (one study) at maintaining stimulated C-peptide. A pilot study showed better metabolic control at six months with subcutaneously administered glutamic acid decarboxylase (GAD) GAD65, a major autoantigen in autoimmune diabetes, compared to placebo. There was no information regarding quality of life, mortality, complications or costs in any of the publications. Time from diagnosis varied between recruitment at diagnosis to recruitment at nine years of disease duration and there was a great deal of variation in the selection criteria for LADA patients, making it difficult to generalise findings from these studies.. There are few studies on this topic and existing studies have a high risk of bias. However, there does seem to be an indication that SU should not be a first line treatment for antibody positive type 2 diabetes. There is no significant evidence for or against other lines of treatment of LADA. Topics: Adult; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Drugs, Chinese Herbal; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Randomized Controlled Trials as Topic; Rosiglitazone; Sulfonylurea Compounds; Thiazolidinediones | 2007 |
[Proinsulin C-peptide -- the bioactive peptide with a huge promise].
Proinsulin connecting peptide (C-peptide) has been initially regarded as deprived of biological functions other than correct scaffolding of insulin. This was caused by the lack of evident effect of C-peptide administration to healthy subjects or animals. At present, in view of numerous studies concerning its structure, membrane binding and biological functions, C-peptide seems to constitute a crucial role in the pathogenesis of complications in diabetes mellitus type 1 (DM1). Patients who maintain high remnant insulin secretion (and therefore also of C-peptide) develop complications such as nephropathy, neuropathy and later microangiopathy with a milder clinical course. In this article we have covered molecular and cellular aspects of C-peptide functioning, such as: activation of protein kinase C, Na+,K+- ATP-ase, nitric oxide synthase, MAP and ERK 1/2 kinases, improvement of nerve conduction velocity and interactions with exogenous and endogenous insulin. We also outline the clinical consequences of deficiency of this underestimated peptide along with its potential therapeutical possibilities in the primary and secondary prevention of DM1 complications. Topics: Amino Acid Sequence; Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Humans; Insulin; Proinsulin; Rats; Signal Transduction | 2007 |
Clinical presentation and treatment of type 2 diabetes in children.
Type 2 diabetes mellitus (T2DM) has dramatically increased throughout the world in many ethnic groups and among people with diverse social and economic backgrounds. This increase has also affected the young such that over the past decade, the increase in the number of children and youth with T2DM has been labeled an 'epidemic'. Before the 1990s, it was rare for most pediatric centers to have significant numbers of patients with T2DM. However, by 1994, T2DM patients represented up to 16% of new cases of diabetes in children in urban areas and by 1999, depending on geographic location, the range of percentage of new cases because of T2DM was 8-45% and disproportionately represented among minority populations. Although the diagnosis was initially regarded with skepticism, T2DM is now a serious diagnostic consideration in all young people who present with signs and symptoms of diabetes in the USA. Topics: Adolescent; Age of Onset; C-Peptide; Child; Combined Modality Therapy; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Diet, Diabetic; Exercise; Humans; Hypoglycemic Agents; Insulin; Obesity; Patient Education as Topic; Sex Factors | 2007 |
The rise and fall of insulin secretion in type 1 diabetes mellitus.
An understanding of the natural history of beta cell responses is an essential prerequisite for interventional studies designed to prevent or treat type 1 diabetes. Here we review published data on changes in insulin responses in humans with type 1 diabetes. We also describe a new analysis of C-peptide responses in subjects who are at risk of type 1 diabetes and enrolled in the Diabetes Prevention Trial-1 (DPT-1). C-peptide responses to a mixed meal increase during childhood and through adolescence, but show no significant change during adult life; responses are lower in adults who progress to diabetes than in those who do not. The age-related increase in C-peptide responses may account for the higher levels of C-peptide observed in adults with newly diagnosed type 1 diabetes compared with those in children and adolescents. Based on these findings, we propose a revised model of the natural history of the disease, in which an age-related increase in functional beta cell responses before the onset of autoimmune beta cell damage is an important determinant of the clinical features of the disease. Topics: Adolescent; Adult; Aging; Autoimmunity; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Prediabetic State | 2006 |
Genetic epidemiology of type 1 diabetes.
The evidence that there is clinical heterogeneity of type 1 diabetes is reviewed and the implications for genetic studies are discussed. In the past year, genome-wide linkage analysis of 1435 multiplex families was reported. Additionally, confirmed evidence for association of specific markers at two loci (PTPN22, OAS1) as well as failure to replicate three others (IL12B, SUMO4, PAX4) is discussed. Some common themes are identified and suggestions for improvements are made. We look forward to the results from genome-wide association studies. Topics: Age of Onset; C-Peptide; Diabetes Mellitus, Type 1; Genetic Linkage; Genetic Variation; Humans; Major Histocompatibility Complex; Proteins; Risk Factors; Siblings | 2006 |
Pathological mechanisms involved in diabetic neuropathy: can we slow the process?
Diabetic polyneuropathy (DPN) is the most common late diabetic complication, and is more frequent and severe in the type 1 diabetic population. Currently, no effective therapy exists to prevent or treat this complication. Hyperglycemia remains a major therapeutic target when dealing with DPN in both type 1 and type 2 diabetes, and should be supplemented by aldose reductase inhibition and antioxidant treatment. However, in the past few years, preclinical and clinical data have indicated that factors other than hyperglycemia contribute to DPN, and these factors account for the disproportionality of prevalence of DPN between the two types of diabetes. Insulin and C-peptide deficiencies have emerged as important pathogenetic factors and underlie the acute metabolic abnormalities, as well as serious chronic perturbations of gene regulatory mechanisms, impaired neurotrophism, protein-protein interactions and specific degenerative disorders that characterize type 1 DPN. It has become apparent that in insulin-deficient conditions, such as type 1 diabetes and advanced type 2 diabetes, both insulin and C-peptide must be replaced in order to gain hyperglycemic control and to combat complications. As with any chronic ailment, emphasis should be on the prevention of DPN; as the disease progresses, metabolic interventions, be they directed against hyperglycemia and its consequences or against insulin/ C-peptide deficiencies, are likely to be increasingly ineffective. Topics: Aldehyde Reductase; Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Humans; Hyperglycemia; Lipid Metabolism; Nerve Degeneration; Nerve Growth Factor; Oxidative Stress; Polymers | 2006 |
[Diagnosis of and therapy for fulminant type 1 diabetes mellitus].
Topics: Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Early Diagnosis; Glycated Hemoglobin; HLA-DR4 Antigen; Humans; Insulin; Insulin-Secreting Cells; Japan; Linkage Disequilibrium; Prognosis; Th1 Cells; Time Factors; Virus Diseases | 2006 |
Pancreatic islet transplantation, what has been achieved since Edmonton break-through.
It has been 6 years since the Edmonton group published their outstanding results with pancreatic islet transplantation patients, demonstrating one-year insulin independence of 100% with type I diabetics. In order to assess what has been achieved for past six years we analyzed the actual state of islet transplantation, based on the updated summary of results from Edmonton and compare this experience with combined results from 19 institutions in North America as reported to the Collaborative Islet Transplant Registry (CITR). CITR data have largely substantiated the reproducibility of the Edmonton procedure. Complete insulin-independence was achieved in more then 55% of patients 1 year after transplant, but this state has not been sustained permanently. Although only 10% of patients remained insulin-free after 5 years, more then 80% of them had still detectable levels of C peptide and substantially improved glycemic control without episodes of hypoglycemia. Even though currently, the islet graft is still not a remedy for every brittle diabetic, islet transplantation has already obtained "nonresearch" status in Canada and is close to having a biological license status approved by the FDA in the United States that would further stimulate progress in the field. Topics: C-Peptide; Canada; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; North America; Registries; Reproducibility of Results; Time Factors | 2006 |
Clinical inquiries: What is the best way to distinguish type 1 and 2 diabetes?
Topics: Adiponectin; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Intercellular Signaling Peptides and Proteins; Leptin | 2005 |
Mechanisms of endothelial dysfunction with development of type 1 diabetes mellitus: role of insulin and C-peptide.
Complications associated with insulin-dependent diabetes mellitus (type-1diabetes) primarily represent vascular dysfunction that has its origin in the endothelium. While many of the vascular changes are more accountable in the late stages of type-1diabetes, changes that occur in the early or initial functional stages of this disease may precipitate these later complications. The early stages of type-1diabetes are characterized by a diminished production of both insulin and C-peptide with a significant hyperglycemia. During the last decade numerous speculations and theories have been developed to try to explain the mechanisms responsible for the selective changes in vascular reactivity and/or tone and the vascular permeability changes that characterize the development of type-1diabetes. Much of this research has suggested that hyperglycemia and/or the lack of insulin may mediate the observed functional changes in both endothelial cells and vascular smooth muscle. Recent studies suggest several possible mechanisms that might be involved in the observed decreases in vascular nitric oxide (NO) availability with the development of type-1 diabetes. In addition more recent studies have indicated a direct role for both endogenous insulin and C-peptide in the amelioration of the observed endothelial dysfunction. These results suggest a synergistic action between insulin and C-peptide that facilitates increase NO availability and may suggest new clinical treatment modalities for type-1 diabetes mellitus. Topics: C-Peptide; Diabetes Mellitus, Type 1; Endothelium, Vascular; Humans; Insulin; Models, Biological; Nitric Oxide; Oxidative Stress; Vasodilation | 2005 |
Latent autoimmune diabetes in adults: a guide for the perplexed.
Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Genetic Markers; Genetic Predisposition to Disease; Glutamate Decarboxylase; Humans; Insulin; Islets of Langerhans; Predictive Value of Tests; Terminology as Topic | 2005 |
Natural history of beta-cell function in type 1 diabetes.
Despite extensive and ongoing investigations of the immune mechanisms of autoimmune diabetes in humans and animal models, there is much less information about the natural history of insulin secretion before and after the clinical presentation of type 1 diabetes and the factors that may affect its course. Studies of insulin production previously published and from the Diabetes Prevention Trial (DPT)-1 suggest that there is progressive impairment in insulin secretory responses but the reserve in response to physiological stimuli may be significant at the time of diagnosis, although maximal responses are more significantly impaired. Other factors, including insulin resistance, may play a role in the timing of clinical presentation along this continuum. The factors that predict the occurrence and rapidity of decline in beta-cell function are still largely unknown, but most studies have identified islet cell autoantibodies as predictors of future decline and age as a determinant of residual insulin production at diagnosis. Historical as well as recent clinical experience has emphasized the importance of residual insulin production for glycemic control and prevention of end-organ complications. Understanding the modifiers and predictors of beta-cell function would allow targeting immunological approaches to those individuals most likely to benefit from therapy. Topics: Adolescent; Adult; Aging; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Resistance; Insulin Secretion; Islets of Langerhans; Middle Aged | 2005 |
Treatment of type 1 diabetes mellitus to preserve insulin secretion.
Topics: Autoimmune Diseases; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Immunosuppression Therapy; Immunotherapy; Insulin; Insulin Secretion | 2004 |
Insulin, C-peptide, hyperglycemia, and central nervous system complications in diabetes.
Diabetes is an increasingly common disorder which causes and contributes to a variety of central nervous system (CNS) complications which are often associated with cognitive deficits. There appear to be two types of diabetic encephalopathy. Primary diabetic encephalopathy is caused by hyperglycemia and impaired insulin action, which evolves in a diabetes duration-related fashion and is associated with apoptotic neuronal loss and cognitive decline. This appears to be particularly associated with insulin-deficient diabetes. Secondary diabetic encephalopathy appears to arise from hypoxic-ischemic insults due to underlying microvascular disease or as a consequence of hypoglycemia. This type of cerebral diabetic complication is more common in the type 2 diabetic population. Here, we will review the clinical and experimental data supporting this conceptual division of diabetic CNS complications and discuss the underlying metabolic, molecular, and functional aberrations. Topics: Animals; Apoptosis; C-Peptide; Central Nervous System Diseases; Cognition; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hyperglycemia; Insulin | 2004 |
Diabetic neuropathy in type 1 and type 2 diabetes and the effects of C-peptide.
Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Disease Models, Animal; Humans; Neural Conduction; Nitric Oxide Synthase; Randomized Controlled Trials as Topic; Sodium-Potassium-Exchanging ATPase | 2004 |
[Maurice Dérot Prize 2004. Should C-peptide be put in the insulin bottle?].
Topics: Blood Circulation; C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Humans; Insulin; Kidney; Nervous System; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Sodium-Potassium-Exchanging ATPase | 2004 |
Markers of beta cell function in type 1 diabetes mellitus.
Type 1 diabetes mellitus is a multifactorial autoimmune disease characterized by destruction of insulin producing pancreatic beta cells that results in insulin deficiency and fasting hyperglycemia. It is now well known that the clinical onset of the disease represents the end stage of an immunological process that occurs over a course of months to years. During this period the presence of autoantibodies against different islet antigens can be detected by the use of standardized assays. The rate of beta cell loss is quite variable among different individuals and at onset ketoacidosis represents still a life threatening complication of the disease. The Diabetes Control and Complication Trial (DCCT) has clearly shown that the preservation of beta cell function in type 1 diabetic subjects results in a better metabolic control and significantly reduces the risk of microvascular complications. Consequently, markers of beta cell function represent important tools to make an early diagnosis and to evaluate the impact of new therapies on the natural history of the disease. The present review will focus on clinical markers currently available (intravenous glucose tolerance test, i.v.GTT, oral glucose tolerance test, OGTT, basal and stimulated C-peptide) to assess the beta cell function in type 1 diabetes. Topics: Age Factors; Autoantibodies; Biomarkers; C-Peptide; Cell Death; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Diabetic Retinopathy; Glucagon; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Islets of Langerhans | 2004 |
[Physiological effects of C-peptide].
Connecting peptide (C-peptide) is a product of proinsulin cleavage. New findings demonstrate, that it may serve to understand the mechanisms involved in the development of long-term complications in type 1 diabetic patients. The present review focuses on: 1. Making a point about C-peptide-induced tubular effects on the basis of clinical and experimental experiments, 2. Precising the molecular mechanisms involved in C-peptide-induced tubular Na,K-ATPase effects. Topics: Animals; C-Peptide; Calcium; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glomerular Filtration Rate; Humans; Nitric Oxide Synthase; Protein Kinase C; Signal Transduction; Sodium-Potassium-Exchanging ATPase | 2004 |
Proprotein processing and pancreatic islet function.
Topics: Amino Acid Sequence; Animals; C-Peptide; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Models, Biological; Molecular Sequence Data; Pancreas; Peptides; Proinsulin; Proprotein Convertase 1; Proprotein Convertase 2; Protein Processing, Post-Translational | 2004 |
Italian Society of Diabetology Mentor Award. The stages of Type 1A diabetes: retrospective and prospective.
In 1986, enough information was available based on studies by investigators from four continents to propose a model of the pathogenesis of Type 1A diabetes. The model divided pathogenesis into a series of stages with the proposal that insulin-dependent diabetes was a chronic autoimmune disorder. Long-term studies of non-diabetic identical twins of patients with Type 1A diabetes indicated that chronic loss of the ability to secrete insulin preceded the onset of diabetes in the presence of both genetic susceptibility and expression of anti-islet autoantibodies. It is now clear that the great majority of individuals who develop Type 1A diabetes show both immunologic and metabolic abnormalities before the development of overt diabetes. A combination of detection of anti-islet autoantibodies, genetic characteristics and metabolic abnormalities can now be used to predict Type 1A diabetes as well as approximate timing of diabetes onset. This knowledge has led to clinical trials on the prevention of Type 1A diabetes that hope to harness a remarkable increase in basic immunologic knowledge and a new generation of immunomodulatory therapies. Despite this increase in knowledge of the natural history of Type 1A diabetes and pathogenesis in animal models, much remains to be defined to allow efficient and successful disease prevention. Topics: Animals; Autoantibodies; Awards and Prizes; C-Peptide; Diabetes Mellitus, Type 1; Environment; Genetic Predisposition to Disease; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Italy; Societies, Medical; Time Factors; Twin Studies as Topic | 2004 |
C-peptide and autoimmune markers in diabetes.
Autoimmune markers such as islet cell antibodies (ICA), glutamic acid decarboxylase antibodies (GADA) and islet antigen-2 antibodies (IA-2A) are found in high frequencies among type 1 patients and especially among younger patients. Presence of these autoantibodies confirms the destructive process of the beta cells associated with immune-mediated type 1 diabetes. Type 2 diabetes is characterised by peripheral insulin resistance and a relative deficiency in insulin production. However, when autoimmune markers are analysed these are found in about 10% of patients clinically classified as type 2 diabetes, indicating that the frequency of type 1 diabetes is underestimated. GADA is the most frequent marker both among patients clinically classified as type 1 and type 2. GADA is also highly predictive for insulin treatment in patients not classified as type 1 diabetes. C-peptide is the best marker of the endogenous insulin production. Sampling of C-peptide is preferably done in the non-fasting condition since these values differentiate better between autoimmune and non-autoimmune diabetes. The presence of autoimmune markers at diagnosis predicts a course of further deteriorating beta cell function, whereas absence of autoimmune markers predicts stable beta cell function for the first two years in adults. Presence of GADA and in particular in high levels are prognostic for a low beta cell function within the next few years after diagnosis. Positivity only for ICA indicates a more preserved beta cell function for the first three years compared to positivity for other autoimmune markers. Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans | 2003 |
C-peptide and diabetic neuropathy.
Diabetic polyneuropathy (DPN) is the most common chronic complication of diabetes and affects Type 1 diabetic patients disproportionately. In the last two decades it has become increasingly evident that underlying metabolic, molecular and functional mechanisms and, ultimately, structural changes differ in DPN between the two major types of diabetes. In Type 1 diabetes, impaired insulin/C-peptide action has emerged as a prominent pathogenetic factor. C-peptide was long considered to be biologically inactive. During the last number of years it has been shown to have a number of insulin-like effects but without affecting blood glucose levels. Preclinical studies have demonstrated effects on Na(+)/K(+)-ATPase activity, endothelial nitric oxide synthase, expression of neurotrophic factors and regulation of molecular species underlying the degeneration of the nodal apparatus in Type 1 diabetic nerves, as well as DNA binding of transcription factors and modulation of apoptotic phenomena. In animal studies, these effects have translated into protection and improvement of functional abnormalities, promotion of nerve fibre regeneration, protection of structural changes and amelioration of apoptotic phenomena targeting central and peripheral nerve cell constituents. Several small-scale clinical trials confirm these beneficial effects on autonomic and somatic nerve function and blood flow in a variety of tissues. Therefore, evidence to date indicating that replacement of C-peptide in patients with Type 1 diabetes will retard and prevent chronic complication is real and encouraging. Large-scale clinical trials necessary to bring this natural substance into the clinical arena should, therefore, be encouraged and accelerated. Topics: C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Humans; Insulin | 2003 |
Type 1 diabetes intervention trials: what have we learned? A critical review of selected intervention trials.
Developing therapies to stop or slow the immune destruction of islets has been a goal of investigators in type 1 diabetes for several decades. This review of clinical interventions in patients with type 1 diabetes indicates both negative and positive outcomes with a variety of different therapeutic agents. An underlying theme of this article is that differences in study design may impact the outcome more than the therapy being tested. Thus, each of these results need to be considered in the context of important variables in study design. To date, there is no clear answer as to what study design is best to determine if an agent is effective against the diabetes disease process; however, the Immunology of Diabetes Society has recently developed guidelines for the conduct of these trials to facilitate comparisons of therapies in the future. Topics: Age Factors; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Practice Guidelines as Topic; Research Design; Treatment Outcome | 2002 |
[C-peptide in blood].
Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diagnosis, Differential; Humans; Hyperinsulinism; Hypoglycemia; Insulin; Insulin Secretion; Reagent Kits, Diagnostic; Reference Values; Sensitivity and Specificity | 2002 |
C-peptide: a new potential in the treatment of diabetic nephropathy.
C-peptide is formed in the biosynthesis of insulin and the two peptides are subsequently released in equimolar amounts to the circulation. C-peptide has long been considered to be without physiologic effects. Recent data now demonstrate that C-peptide in the nanomolar concentration range binds specifically to cell surfaces, probably to G protein-coupled receptors, with subsequent activation of Ca(2+)-dependent intracellular signaling pathways and stimulation of Na+, K(+)-ATPase activities. C-peptide replacement in animal models of type 1 diabetes results in diminished hyperfiltration, improved functional reserve, reduction of urinary albumin excretion, and prevention of glomerular and renal hypertrophy. Administration of C-peptide to physiologic concentrations in patients with type 1 diabetes and incipient nephropathy for periods of 3 hours to 3 months is accompanied by reduced glomerular hyperfiltration and filtration fraction, and diminished urinary albumin excretion. C-peptide replacement together with insulin therapy may be beneficial in type 1 diabetes patients with nephropathy. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans | 2001 |
Does partial preservation of residual beta-cell function justify immune intervention in recent onset Type I diabetes?
Immune intervention seems to offer the prospect of preventing or reversing the hyperglycaemic phase of Type I (insulin-dependent) diabetes mellitus. A number of prevention trials have been undertaken before disease onset but the logistics of such trials are prohibitive. More rapid and less expensive means of testing new therapies are needed and the current emphasis is therefore on intervention after diagnosis to salvage residual beta-cell function. At present, because restoration of normal metabolism seems unattainable, such interventions are tested against their ability to maintain C-peptide production over the first months or years of diabetes. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Hypoglycemia; Immunotherapy; Islets of Langerhans | 2001 |
[C-peptide, new discoveries and therapeutic implications].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Kidney; Nerve Fibers | 1999 |
[C-peptide in blood].
Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Hypoglycemia; Immunoassay; Insulin; Proinsulin; Reagent Kits, Diagnostic | 1998 |
Improvements and new potentials in pharmacological therapy of diabetes mellitus in children and adolescents.
Subcutaneous insulin substitution is not physiological. Despite the many attempts using intensified insulin regimens to render current insulin substitution protocols more physiological, a nondiabetic circulating insulin profile cannot be simulated in patients with type 1 diabetes. Despite many efforts, the pharmacological treatment of type 1 diabetes consists of an unphysiological attempt to substitute only one of the hormones which are lost after beta-cell destruction, namely insulin. It is therefore mandatory to search for additional means to achieve physiological regulation of glucose homeostasis and overall metabolic status. Peptides which are being developed as additional new therapeutic compounds for type 1 diabetes include, for example, IGF-I, leptin, C-peptide and amylin. In addition, the application of insulin analogues has already been introduced into clinical practice. However, so far none of these pharmaceutical compounds has been shown to offer real clinical benefits and substantially improve metabolic control in patients with type 1 diabetes. The results of long-term clinical trials using the peptide compounds listed above for the treatment of type 1 diabetes are still not available. Topics: Adolescent; Amyloid; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin-Like Growth Factor I; Islet Amyloid Polypeptide; Leptin; Proteins | 1998 |
New aspects on biological activity of C-peptide in IDDM patients.
C-peptide, which is released from the pancreatic beta cells into the circulation in amounts equimolar with insulin, fulfills an important function in the assembly of the two-chain insulin structure, but has otherwise been considered to be biologically inactive. However, during the last few years several experimental and clinical studies have demonstrated that replacement of C-peptide in patients with insulin-dependent diabetes mellitus elicits several physiological effects. Thus, during short-term substitution of C-peptide (1-3 h) decreased glomerular hyperfiltration, augmented whole body and skeletal muscle glucose utilisation, improved autonomic nerve function and a redistribution of microvascular skin blood flow could be observed. In addition, replacement of C-peptide during a period of 1-3 months has been shown to improve renal function as well as autonomic and sensory nerve function in IDDM patients. The mechanisms behind these effects remain unclear, but recent investigations have indicated that an increase in Na+K+ATPase activity and a stimulation of the endothelial nitric oxide synthase may contribute to the observed physiological effects of C-peptide. Not only the intact C-peptide molecule, but also fragments from the C-terminal and mid-portion of the molecule have been shown to exert biological effects. Further research will be necessary to evaluate the underlying mechanism and the clinical impact of C-peptide replacement in IDDM patients. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans | 1998 |
[Clinical value of C-peptide determination].
The classification of newly diagnosed diabetic patients as type I (insulin-dependent) or type II (non-insulin-dependent) diabetes and the implied therapeutical consequences there of are based on clinical observations and laboratory tests. In case differential diagnosis is difficult, the measurement of the c-peptide secretion to assess beta-cell capacity can be helpful. For adequate control especially after long-standing diabetes in obese patients it is important to identify patients with potential secondary drug failure. Poor compliance with diet is thought to be a major reason for poor response to treatment. On the other hand, diabetics with poor control because of deterioration of beta-cell function must be distinguished. In these situations the measurement of c-peptide concentrations may contribute to identify the need for insulin treatment. As a result the development of diabetic complications can be retarded and beta-cell function can be preserved by adequate insulin therapy, whereas the consequences of hyperinsulinaemia in insulin treated patients not needing insulin can be avoided. In our opinion the c-peptide/glucose-quotient serves as simple, cost-effective and non-invasive method in the assessment of beta-cell capacity. Insulin therapy is indispensable in the case of inadequate insulin secretion. Topics: Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Middle Aged; Predictive Value of Tests | 1997 |
[Selection of patients to be treated with insulin].
Topics: Aged; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Coma; Diabetic Nephropathies; Female; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Nutrition Disorders; Patient Selection; Pregnancy; Pregnancy in Diabetics | 1997 |
The role of prohormone convertases in insulin biosynthesis: evidence for inherited defects in their action in man and experimental animals.
The hormone insulin remains the cornerstone of diabetic therapy since it is required for almost all cases of Type 1 and many cases of Type 2 diabetes. Since the discovery of insulin in 1921, much has been learned about its chemistry, structure and action as well as its production in the beta cell. Insulin is formed through a series of precursors, beginning with preproinsulin, the protein encoded in the insulin gene. These precursors direct the prohormone into the secretory pathway and ultimately into the secretory granules where it is converted into insulin and C-peptide. These products are stored and secreted together in a highly regulated manner in response to glucose and other stimuli. This review focuses on the recently discovered prohormone convertases, PC2 and PC3 (PC1), the enzymes responsible for the endoproteolytic processing of proinsulin to insulin and C-peptide in the beta cell as well as for the selective processing of proglucagon to glucagon in the alpha cell or GLP1 in intestinal L-cells. PC2 and PC3 are calcium-dependent serine proteases related to the bacterial enzyme subtilisin. They cleave selectively at Lys-Arg or Arg-Arg sites in precursors, generating products with C-terminal basic residues that are then removed by carboxypeptidase E, an exopeptidase. All 3 enzymes are expressed mainly in secretory granules of neuroendocrine cells throughout the body and in the brain. Inherited defects affecting the prohormone-processing enzymes have recently been found in association with unusual syndromes of obesity and other metabolic disorders. Topics: Animals; Aspartic Acid Endopeptidases; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Humans; Insulin; Islets of Langerhans; Obesity; Organ Specificity; Proinsulin; Proprotein Convertase 2; Proprotein Convertases; Subtilisins | 1996 |
C-peptide revisited--new physiological effects and therapeutic implications.
Recent studies have demonstrated that replacement of C-peptide to normal physiological concentrations in insulin-dependent diabetic (IDDM) patients on a short-term basis (1-3 h) results in decreased glomerular hyperfiltration, augmented glucose utilization and improved autonomic nervous function. More prolonged administration (1-3 months) of C-peptide to IDDM patients is accompanied by improvements in both renal and autonomic nervous function. Moreover, both in-vitro and in-vivo studies indicate that C-peptide may have a role in the regulation of insulin secretion. The effects of C-peptide may in part be explained by its ability to stimulate Na+,K(+)-ATPase activity. In conclusion, the combined findings indicate that C-peptide is a biologically active hormone. The possibility that C-peptide therapy in IDDM patients may be beneficial should be considered. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Glucose; Humans; Islets of Langerhans; Kidney; Muscle, Skeletal | 1996 |
Meta-analysis of nicotinamide treatment in patients with recent-onset IDDM. The Nicotinamide Trialists.
Nicotinamide, a vitamin of the B group, has in vitro actions capable of interfering with the pathogenetic process leading to IDDM. Since 1987, several studies have evaluated nicotinamide as a means of protecting beta-cells from end-stage destruction in insulin-treated patients with newly diagnosed IDDM. The aim of the study was to determine whether nicotinamide protects residual beta-cell function when given at IDDM diagnosis.. We performed a meta-analysis of the integrated parameters of metabolic control (C-peptide, glycosylated hemoglobin, insulin dose) in 10 randomized (5 of which were placebo) controlled trials conducted in recent-onset IDDM patients for a total of 211 nicotinamide-treated patients. Data on the adverse effects of nicotinamide were also collected from an additional four trials to yield a grand total of 291 nicotinamide-receiving patients.. One year after diagnosis, baseline C-peptide was significantly higher in nicotinamide-treated patients, compared with control patients (0.73 +/- 0.65 vs. 0.32 +/- 0.56 ng/ml, P < 0.005). This statistical difference remained also when the five placebo-controlled trials only were considered (P < 0.05). No differences were observed in the insulin dose required or glycosylated hemoglobin values between nicotinamide and control patients. Adverse effects were reported in few patients (transient elevation of transaminase, n = 2; skin rash, n = 2; recurrent hypoglycemia, n = 2).. This combined analysis demonstrates a therapeutic effect of nicotinamide in preserving residual beta-cell function when given at IDDM diagnosis in addition to insulin. Since adverse effects were negligible, we suggest that prolonged use of nicotinamide after IDDM diagnosis should be tested to see whether residual beta-cell function can be preserved for longer periods. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Niacinamide; Randomized Controlled Trials as Topic | 1996 |
Assessment of residual insulin secretion in diabetic patients using the intravenous glucagon stimulatory test: methodological aspects and clinical applications.
Defective insulin secretion plays a crucial role in insulin-dependent (Type 1) and non-insulin-dependent (Type 2) diabetes mellitus as well as in many secondary forms of the disease. Glucagon is a potent stimulus for the islet beta-cell, and intravenous bolus injection of 1 mg glucagon has been widely used to assess endogenous insulin secretion for clinical or research purposes. Plasma C-peptide levels (less commonly insulin) are usually measured immediately before and 6 min after glucagon injection. The C-peptide response to glucagon is well-correlated with the beta-cell response to mixed meals or other stimuli commonly used to characterize endogenous insulin secretion (oral or intravenous glucose, standard meals, arginine, etc.) and has the advantage of shorter duration and simple standardization. The glucagon test shows good intra-subject reproducibility, although in diabetic patients it may be influenced by variable prevailing blood glucose levels. Several applications of the glucagon test have been developed. In Type 1 diabetes, the glucagon test has been used to discriminate between patients with and without residual insulin secretion. This can be especially important during the first few months, or even years, following initiation of insulin therapy when attempts to stop the immunological destruction of the beta-cell are made. Assessment of endogenous insulin secretion is also important after pancreas or islet transplantation. In patients with Type 2 diabetes mellitus, in which residual endogenous insulin secretion is common, characterization of the disease may help in the choice of therapy for the individual patient (insulin, sulphonylureas or combined therapy). Thus, the glucagon test is a simple, reliable and useful tool for clinical evaluation of diabetes mellitus. Topics: Arginine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion | 1996 |
[C-peptide (CPR)].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Radioimmunoassay | 1995 |
Does C-peptide have a physiological role?
Short-term administration of physiological amounts of C-peptide to patients with insulin-dependent diabetes was found to reduce the glomerular hyperfiltration in these patients as well as augment whole body glucose utilization. It could also be shown that C-peptide administration increases blood flow, oxygen uptake and capillary diffusion capacity of exercising forearm muscle in IDDM patients, probably by increasing capillary recruitment in the working muscle. Studies under in vitro conditions have shown that C-peptide stimulates glucose transport in skeletal muscle with its maximal effect within the physiological concentration range. The findings in a clinical study in which IDDM patients were given C-peptide and insulin or insulin alone for 4 weeks in a double-blind randomized study design, indicate that C-peptide improves renal function by reducing urinary albumin excretion and glomerular filtration, decreases blood retinal barrier leakage and improves metabolic control. Preliminary findings suggest that C-peptide administration on a short-term basis (3h) may ameliorate autonomic neuropathy by restoring to near normal the heart rate variability in response to expiration and inspiration. Insight into a possible mechanism of action of C-peptide is provided by the finding that C-peptide stimulates Na+K(+)-ATPase activity in renal tubular segments. In conclusion, the present results suggest that, contrary to the prevailing view, C-peptide possesses important physiological effects. Topics: Animals; Awards and Prizes; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Double-Blind Method; Europe; Glucose; History, 20th Century; Humans; Insulin; Kidney; Muscles; Randomized Controlled Trials as Topic; Regional Blood Flow; Societies, Medical; Sweden | 1994 |
Limitations in the use of insulin or C-peptide alone in the assessment of beta-cell function in pancreas transplant recipients. Danish-Swedish Study Group of Metabolic Effect of Pancreas Transplantation.
Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Pancreas Transplantation | 1994 |
Anti-CD4 therapy in recent-onset IDDM.
Topics: Animals; Antibodies, Monoclonal; Antilymphocyte Serum; Autoimmunity; C-Peptide; CD4-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans | 1993 |
New directions in drug development: mixtures, analogues, and modeling.
Success in modern medical research is achieved when basic and clinical information about a given disorder converges, either intentionally or fortuitously, with the availability of technology or other means to design and apply interventions for the disorder in question. A prime example is the discovery of insulin and its replacement in patients with IDDM in 1923. Seven decades later, the focus of diabetes management is on improvement in metabolic control to forestall the chronic complications of the disease and improve the quality of life of patients with the disease. Metabolic control is being addressed through the development of insulin analogues using sophisticated techniques to understand the chemistry of insulin and to modify it using rDNA technology. The objective of these efforts is to simulate normal insulin secretion with subcutaneously injected agonists. Quality-of-life needs are being addressed with delivery devices, insulin mixtures, and insulin analogues. Although none of these improvements parallel the discovery of insulin, they do provide an optimistic outlook for patients with diabetes mellitus. Topics: Amino Acid Sequence; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Design; Humans; Insulin; Insulin Secretion; Molecular Sequence Data; Proinsulin; Protein Conformation; Quality of Life; Recombinant Proteins | 1993 |
[Progress in insulin therapy. V. Insulin therapy in noninsulin dependent diabetes mellitus].
Topics: C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Drug Administration Schedule; Humans; Insulin | 1992 |
C-peptide used in the estimation of islet beta-cell function in diabetes.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Insulin; Insulin Secretion; Islets of Langerhans | 1992 |
Case report: factitious hypoglycemia in diabetic patients.
Factitious hypoglycemia (FH) in a diabetic patient represents a difficult diagnostic and costly management problem. An adolescent diabetic with FH is reported. A literature search revealed 10 adolescent and 45 adult diabetic patients with FH. Tests currently available for diagnosis are evaluated. The role of psychiatric therapy in relation to overall management and prognosis is stressed. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Factitious Disorders; Humans; Hypoglycemia; Insulin; Male | 1992 |
Epidemiology of proliferative diabetic retinopathy.
This review examines recent epidemiological data about the prevalence and incidence of and risk factors for proliferative diabetic retinopathy. In addition, the relation of proliferative retinopathy to other systemic complications associated with diabetes is reviewed.. The data come mostly from the baseline and 4-yr follow-up examinations of a large population-based study, the WESDR, which involved 996 younger-onset insulin-dependent people whose diabetes was diagnosed at < 30 yr of age and 1370 older-onset people whose diabetes was diagnosed at > or = 30 yr of age, and who were taking or not taking insulin.. The major finding is that proliferative retinopathy is a prevalent complication (23% in the WESDR younger-onset group, 10% in the WESDR older-onset group that takes insulin, and 3% in the group that does not take insulin). Hyperglycemia, longer duration of diabetes, and more severe retinopathy at baseline were associated with an increased 4-yr risk of developing proliferative retinopathy. However, higher blood pressure at baseline was associated only with the development of proliferative retinopathy in the younger-onset group. The presence of proliferative diabetic retinopathy was associated with an increased 4-yr risk of loss of vision, cardiovascular disease, diabetic nephropathy, and mortality. In the WESDR, a significant number of diabetic people with proliferative retinopathy at risk for vision loss were not under the care of an ophthalmologist or had not undergone panretinal photocoagulation.. These data suggest that hyperglycemia and, possibly, high blood pressure are related to proliferative retinopathy. They also suggest that once proliferative diabetic retinopathy is detected, people should have a medical evaluation, because it is a strong indicator for the presence and development of systemic disease. These data also indicate that diabetic patients and their physicians should be aware of the need for routine ophthalmological examinations to detect and treat proliferative retinopathy. Topics: Age Factors; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Humans; Incidence; Morbidity; Prevalence; Risk Factors; Sex Factors | 1992 |
[Postprandial hypoglycemia and alcohol drinking].
Topics: Alcohol Drinking; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Eating; Evaluation Studies as Topic; Humans; Hypoglycemia; Insulin; Insulin Secretion | 1992 |
Impact of activated glucose counterregulation on insulin requirements in insulin-dependent diabetes mellitus.
The glucose counterregulatory system is one of the most important homeostatic systems in physiology, since it normally prevents hypoglycaemia or, should it occur for any reason such as insulin administration, limits the severity of hypoglycaemia and ultimately may restore normoglycaemia. In normal nondiabetic subjects, activation of counterregulation does not result in overt hyperglycaemia in the post-absorptive state, because the pancreatic beta-cell increases insulin secretion. On the contrary, in subjects with insulin-dependent diabetes mellitus (IDDM) whose pancreatic B-cell cannot respond to an increase in plasma glucose, activated counterregulation may easily result in overt hyperglycaemia. There are two different circumstances under which counterregulation may contribute to excessive hyperglycaemia in IDDM, namely nonhypoglycaemic nocturnal activation of counterregulation (dawn phenomenon), and hypoglycaemic activation of counterregulation (Somogyi phenomenon). The dawn phenomenon is an increase in insulin requirements which occurs between 04.00 and 08.00 h in the absence of preceding hypoglycaemia and concomitant hypoinsulinemia. It is caused by a decrease in hepatic and extrahepatic sensitivity to insulin induced by the nocturnal secretion of growth hormone. The dawn phenomenon may contribute importantly to fasting hyperglycaemia in IDDM, because usually plasma insulin concentration following the pre-supper insulin injection decreases after 04.00 h, i.e. a time at which plasma insulin concentration should instead increase to maintain normoglycaemia. The Somogyi phenomenon is best defined as hyperglycaemia following hypoglycaemia and is caused by the insulin resistance induced by hypoglycaemic-activation of counterregulation. Although insulin resistance following hypoglycaemia is a constant event in IDDM, post-hypoglycaemic hyperglycaemia is not the rule. For example, if the responses of counterregulatory hormones to nocturnal hypoglycaemia are blunted, or plasma insulin concentration following hypoglycaemia is inappropriately high, post-hypoglycaemic insulin resistance is not powerful enough to result in overt hyperglycaemia in the fasting state. However, post-breakfast plasma glucose may be exaggerately elevated following nocturnal hypoglycaemia even in the case that fasting plasma glucose is only modestly increased. It is important to prevent nocturnal hypoglycaemia, not only to protect brain function, but also to prevent insulin resistance whi Topics: Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Glucose; Homeostasis; Humans; Insulin | 1990 |
[C-peptide measurement in the classification of diabetes mellitus and in the assessment of requirements for insulin treatment].
C-peptide and insulin are secreted in equimolar amounts from the beta-cells in the pancreas. Therefore, measurement of C-peptide in plasma can be used to estimate endogenous insulin secretion also in insulin treated diabetic subjects. From a clinical point of view, it is of especial interest to use measurements of C-peptide in the discrimination between diabetic subjects with and without insulin requirements. Such measurements are, however, difficult to interpret. Thus, plasma C-peptide values depend apart from C-peptide secretion also on C-peptide clearence, technical procedures, and during unsteady state conditions also on the C-peptide volume of distribution. In clinical practice, it is recommended only to measure basal plasma C-peptide and these values should be interpreted with caution. Generally, values below 0.2 nmol/l suggest insulin requirement while values above 0.5 nmol/l suggest non-insulin requirement. Patients with intermediate basal plasma C-peptide values should be evaluated more closely for example in hospital. Measurement of C-peptide should, however, be restricted to certain selected patients in whom the clinical classification is uncertain. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin | 1990 |
Diabetic honeymoon: prolonged at a price?
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Pancreas Transplantation; Remission Induction; Time Factors | 1989 |
Pancreas transplantation--1985.
Topics: Adult; Animals; C-Peptide; Carbohydrate Metabolism; Cattle; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Dogs; Graft Survival; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Kidney Transplantation; Middle Aged; Pancreas; Pancreas Transplantation; Pancreatic Ducts; Postoperative Complications; Stomach; Vasculitis | 1986 |
C-peptide: an index of insulin secretion.
Insight into the natural history of beta cell function in IDDM patients obtained by C-peptide measurements is reviewed. It is argued that residual insulin secretion of metabolic importance is present in all IDDM patients during the initial course of the disease. After some months, beta cell function reaches its maximum; thereafter it declines at different rates dependent on the age at onset of diabetes and, possibly, on the presence of ICA and HLA-antigens. As many as 15% of IDDM patients retain life-long beta cell function that persists at approximately 10% of that observed in nondiabetic individuals. The residual endogenous insulin secretion is characterized by reduced capacity, as well as abnormal insulin secretory kinetics; these defects in residual insulin secretion can be modulated by changes in metabolic regulation as well as by immunosuppression during the initial course of the disease. Topics: Age Factors; Animals; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Immunoglobulin G; Insulin; Insulin Secretion; Islets of Langerhans; Kinetics | 1986 |
Insulin-dependent diabetes mellitus: pathophysiology.
Diabetes mellitus is a heterogeneous disorder. About 80% of the patients with this disease are categorized as having non-insulin-dependent diabetes mellitus, a disorder resulting from varied degrees of insulin resistance and impaired insulin secretion; the causes for these abnormalities are unknown. The remaining 15 to 20% of patients have insulin-dependent diabetes mellitus, a disorder caused by the destruction of insulin-producing endocrine cells within the pancreas and currently considered to be the result of an autoimmune process. During the course of both types of diabetes mellitus, the so-called long-term complications of diabetes invariably occur to some extent in all patients. These complications include retinopathy, nephropathy, neuropathy, and premature atherosclerosis. The molecular basis for these complications is not completely understood, but recent evidence obtained from both experiments in animals and prospective clinical studies indicates that metabolic derangements associated with poor glycemic control are a major determinant of the frequency and severity of these complications. Such evidence is the rationale for current attempts to maintain near-normal glycemia in patients with diabetes mellitus. Topics: Autoimmune Diseases; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Diagnosis, Differential; Glucagon; Humans; Insulin; Insulin Resistance | 1986 |
Molecular biology of type 1 (insulin-dependent) diabetes mellitus.
Topics: Antigen-Antibody Reactions; Antigen-Presenting Cells; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Histocompatibility Antigens Class II; Humans; Insulin; Islets of Langerhans; Risk; T-Lymphocytes, Helper-Inducer | 1985 |
Biologic and clinical importance of proinsulin.
Topics: Adolescent; Animals; Base Sequence; C-Peptide; Diabetes Mellitus, Type 1; DNA, Recombinant; Drug Contamination; Female; Genes; Glucose; Humans; Insulin; Insulin Antibodies; Insulinoma; Liver; Male; Middle Aged; Pancreatic Neoplasms; Pregnancy; Pregnancy in Diabetics; Proinsulin; Protein Biosynthesis; Protein Precursors; RNA, Messenger | 1984 |
C-peptide measurement: methods and clinical utility.
Proinsulin is the single chain precursor of insulin. It consists of insulin, plus a peptide which connects the A and B chains of insulin. This peptide is termed C-peptide. C-peptide an insulin are secreted in equimolar amounts from pancreatic beta-cells, Hence, circulating C-peptide levels provide a measure of beta-cell secretory activity. C-peptide measurements are preferable to insulin measurements because of lack of hepatic extraction, slower metabolic clearance rate, and lack of cross reactivity with antibodies to insulin. This article reviews the methods for determination of C-peptide levels in body fluids, and discusses the applications of C-peptide measurement. These include the investigation of hypoglycemia and the assessment of insulin secretory function in insulin-treated and non-insulin-dependent diabetics. The contribution of C-peptide measurement to the understanding of the interrelationships between insulin secretory function and age, sex, obesity, blood lipids, and blood glucose concentrations will also be evaluated. Topics: Amniotic Fluid; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucose Tolerance Test; Humans; Hyperinsulinism; Hypoglycemia; Insulin; Islets of Langerhans; Kidney; Liver; Male; Obesity; Pregnancy; Proinsulin; Radioimmunoassay; Reference Values | 1984 |
C-peptide as a measure of the secretion and hepatic extraction of insulin. Pitfalls and limitations.
The large and variable hepatic extraction of insulin is a major obstacle to our ability to quantitate insulin secretion accurately in human subjects. The evidence that C-peptide is secreted from the beta cell in equimolar concentration with insulin, but not extracted by the liver to any significant degree, has provided a firm scientific basis for the use of peripheral C-peptide concentrations as a semiquantitative marker of beta cell secretory activity in a variety of clinical situations. Thus, plasma C-peptide has proved to be extremely valuable in the study of the natural history of type 1 diabetes, to monitor insulin secretion in patients with insulin antibodies, and as an adjunct in the investigation of patients with hypoglycemic disorders. The use of the peripheral C-peptide concentration to accurately quantitate the rate of insulin secretion is more controversial. This is mainly because understanding of the kinetics and metabolism of C-peptide under different conditions is incomplete. Unfortunately, sufficient quantities of human C-peptide are not available to allow the experimental validation of the mathematical formulae that have been proposed for the calculation of insulin secretion from peripheral C-peptide concentrations. Until it is possible to perform such experiments, the accuracy of studies that have derived insulin secretion rates from peripheral C-peptide levels will remain uncertain. The assumption that the peripheral C-peptide:insulin molar ratio can be used as a reflection of hepatic insulin extraction has not been experimentally validated. The marked difference in the plasma half-lives of insulin and C-peptide complicates the interpretation of changes in their ratios.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Glucose Tolerance Test; Half-Life; Humans; Insulin; Insulin Secretion; Kidney Diseases; Kinetics; Liver; Male; Metabolic Clearance Rate; Obesity; Tissue Distribution | 1984 |
[Insulin therapy in 1984].
Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Delayed-Action Preparations; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Retinopathy; Glycated Hemoglobin; Glycosuria; Humans; Hypoglycemia; Insulin; Insulin Infusion Systems; Insulin Secretion; Time Factors | 1984 |
C-peptide and free insulin determinations in type I diabetes; relationships with metabolic control and insulin therapy.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Humans; Insulin; Islets of Langerhans | 1984 |
[The natural history of diabetes with respect to disorders of insulin function].
Topics: Adolescent; Adult; Animals; Blood Glucose; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Insulin Secretion; Islets of Langerhans; Time Factors | 1984 |
C-peptide measurement and its clinical usefulness: a review.
Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Hypoglycemia; Infant, Newborn; Insulin; Insulinoma; Islets of Langerhans; Kidney Function Tests; Middle Aged; Peptides; Radioimmunoassay | 1981 |
[C-peptide immunoreactivity CPR), urine CPR, beta-cell function (author's transl)].
Topics: Adolescent; Amino Acid Sequence; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Peptides; Proinsulin; Radioimmunoassay | 1981 |
[New aspects in the pathogenesis and in the course of type-I-diabetes mellitus (author's transl)].
Topics: Antibodies, Viral; Antigen-Antibody Complex; Autoantibodies; C-Peptide; Cross Reactions; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Retinopathy; Enterovirus; HLA Antigens; Humans; Hyperthyroidism; Islets of Langerhans; Killer Cells, Natural; Receptors, Cell Surface; Risk; Thyroid Gland; Thyrotropin | 1980 |
[The artificial endocrine pancreas in clinical medicine and in research].
Topics: Artificial Organs; Blood Glucose; C-Peptide; Circadian Rhythm; Computers; Diabetes Mellitus, Type 1; Diabetic Coma; Humans; Hypoglycemia; Insulin; Islets of Langerhans; Pancreas; Prostheses and Implants; Somatostatin; Sulfonylurea Compounds | 1976 |
358 trial(s) available for c-peptide and Diabetes-Mellitus--Type-1
Article | Year |
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Two-Year Follow-up From the T1GER Study: Continued Off-Therapy Metabolic Improvements in Children and Young Adults With New-Onset T1D Treated With Golimumab and Characterization of Responders.
The T1GER (A Study of SIMPONI to Arrest β-Cell Loss in Type 1 Diabetes) study showed many metabolic benefits of the tumor necrosis factor-α blocker golimumab in children and young adults with type 1 diabetes (T1D). Off-therapy effects are reported.. T1GER was a phase 2, placebo-controlled, randomized trial in which golimumab or placebo was administered for 52 weeks to participants 6-21 years old diagnosed with T1D within 100 days of randomization. Assessments occurred during the 52-week on-therapy and 52-week off-therapy periods.. After treatment was stopped, C-peptide area under the curve (AUC) remained greater in the treatment versus control group. At weeks 78 and 104, the golimumab group had lower reductions in the 4-h C-peptide AUC baseline than the placebo group, where specifically the golimumab group had reductions of 0.31 and 0.41 nmol/L, and the placebo group had reductions of 0.64 and 0.74 nmol/L. There were also trends in less insulin use, higher peak C-peptide levels and those in partial remission, and higher peak C-peptide levels in the golimumab group. Golimumab responders, defined as having an increase or minimal loss of C-peptide AUC and/or being in partial remission at week 52, showed even greater improvements in most metabolic parameters on and off therapy and had less hypoglycemia during the off-therapy period versus placebo. Adverse events, including infections, were similar between the groups during all time periods of the study.. In children and young adults with new-onset T1D, golimumab preserved endogenous β-cell function and resulted in other favorable metabolic parameters on and off therapy. A subpopulation had disease stabilization while on therapy, with improved metabolic parameters off therapy. Topics: Adolescent; Adult; Antibodies, Monoclonal; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Follow-Up Studies; Humans; Treatment Outcome; Young Adult | 2023 |
Intralymphatic glutamic acid decarboxylase administration in type 1 diabetes patients induced a distinctive early immune response in patients with DR3DQ2 haplotype.
GAD-alum given into lymph nodes to Type 1 diabetes (T1D) patients participating in a multicenter, randomized, placebo-controlled double-blind study seemed to have a positive effect for patients with DR3DQ2 haplotype, who showed better preservation of C-peptide than the placebo group. Here we compared the immunomodulatory effect of GAD-alum administered into lymph nodes of patients with T1D versus placebo with focus on patients with DR3DQ2 haplotype.. GAD autoantibodies, GADA subclasses, GAD. Higher GADA, GADA subclasses, GAD. Patients with DR3DQ2 haplotype had a distinct early cellular immune response to GAD-alum injections into the lymph node, and predominant GAD Topics: C-Peptide; Cytokines; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Haplotypes; HLA Antigens; Humans; Immunity, Cellular; Interleukin-10; Interleukin-13; Interleukin-5 | 2023 |
Combination therapy with saxagliptin and vitamin D for the preservation of β-cell function in adult-onset type 1 diabetes: a multi-center, randomized, controlled trial.
Disease modifying therapies aiming to preserve β-cell function in patients with adult-onset autoimmune type 1 diabetes are lacking. Here, we conducted a multi-centre, randomized, controlled trial to assess the β-cell preservation effects of saxagliptin alone and saxagliptin combined with vitamin D as adjunctive therapies in adult-onset autoimmune type 1 diabetes. In this 3-arm trial, 301 participants were randomly assigned to a 24-month course of the conventional therapy (metformin with or without insulin) or adjunctive saxagliptin or adjunctive saxagliptin plus vitamin D to the conventional therapy. The primary endpoint was the change from baseline to 24 months in the fasting C-peptide. The secondary endpoints included the area under the concentration-time curve (AUC) for C-peptide level in a 2-h mixed-meal tolerance test, glycemic control, total daily insulin use and safety, respectively. The primary endpoint was not achieved in saxagliptin plus vitamin D group (P = 0.18) and saxagliptin group (P = 0.26). However, compared with the conventional therapy, 2-h C-peptide AUC from 24 months to baseline decreased less with saxagliptin plus vitamin D (-276 pmol/L vs. -419 pmol/L; P = 0.01), and not to the same degree with saxagliptin alone (-314 pmol/L; P = 0.14). Notably, for participants with higher glutamic acid decarboxylase antibody (GADA) levels, the decline of β-cell function was much lower in saxagliptin plus vitamin D group than in the conventional therapy group (P = 0.001). Insulin dose was significantly reduced in both active treatment groups than in the conventional therapy group despite all groups having similar glycemic control. In conclusion, the combination of saxagliptin and vitamin D preserves pancreatic β-cell function in adult-onset autoimmune type 1 diabetes, an effect especially efficacious in individuals with higher GADA levels. Our results provide evidence for a novel adjunct to insulin and metformin as potential initial treatment for adult-onset type 1 diabetes. (ClinicalTrials.gov identifier: NCT02407899). Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Drug Therapy, Combination; Humans; Hypoglycemic Agents; Insulin; Metformin; Vitamin D | 2023 |
Umbilical cord-derived mesenchymal stromal cells preserve endogenous insulin production in type 1 diabetes: a Phase I/II randomised double-blind placebo-controlled trial.
This study aimed to investigate the safety and efficacy of treatment with allogeneic Wharton's jelly-derived mesenchymal stromal cells (MSCs) in recent-onset type 1 diabetes.. A combined Phase I/II trial, composed of a dose escalation followed by a randomised double-blind placebo-controlled study in parallel design, was performed in which treatment with allogeneic MSCs produced as an advanced therapy medicinal product (ProTrans) was compared with placebo in adults with newly diagnosed type 1 diabetes. Inclusion criteria were a diagnosis of type 1 diabetes <2 years before enrolment, age 18-40 years and a fasting plasma C-peptide concentration >0.12 nmol/l. Randomisation was performed with a web-based randomisation system, with a randomisation code created prior to the start of the study. The randomisation was made in blocks, with participants randomised to ProTrans or placebo treatment. Randomisation envelopes were kept at the clinic in a locked room, with study staff opening the envelopes at the baseline visits. All participants and study personnel were blinded to group assignment. The study was conducted at Karolinska University Hospital, Stockholm, Sweden.. Three participants were included in each dose cohort during the first part of the study. Fifteen participants were randomised in the second part of the study, with ten participants assigned to ProTrans treatment and five to placebo. All participants were analysed for the primary and secondary outcomes. No serious adverse events related to treatment were observed and, overall, few adverse events (mainly mild upper respiratory tract infections) were reported in the active treatment and placebo arms. The primary efficacy endpoint was defined as Δ-change in C-peptide AUC for a mixed meal tolerance test at 1 year following ProTrans/placebo infusion compared with baseline performance prior to treatment. C-peptide levels in placebo-treated individuals declined by 47%, whereas those in ProTrans-treated individuals declined by only 10% (p<0.05). Similarly, insulin requirements increased in placebo-treated individuals by a median of 10 U/day, whereas insulin needs of ProTrans-treated individuals did not change over the follow-up period of 12 months (p<0.05).. This study suggests that allogeneic Wharton's jelly-derived MSCs (ProTrans) is a safe treatment for recent-onset type 1 diabetes, with the potential to preserve beta cell function.. ClinicalTrials.gov NCT03406585 FUNDING: The sponsor of the clinical trial is NextCell Pharma AB, Stockholm, Sweden. Topics: Adolescent; Adult; C-Peptide; COVID-19; Diabetes Mellitus, Type 1; Double-Blind Method; Humans; Insulin; Mesenchymal Stem Cells; SARS-CoV-2; Treatment Outcome; Umbilical Cord; Young Adult | 2023 |
First-in-human, double-blind, randomized phase 1b study of peptide immunotherapy IMCY-0098 in new-onset type 1 diabetes.
Type 1 diabetes (T1D) is a CD4. This first-in-human, 24-week, double-blind phase 1b study evaluated the safety of three dosages of IMCY-0098 in adults diagnosed with T1D < 6 months before study start. Forty-one participants were randomized to receive four bi-weekly injections of placebo or increasing doses of IMCY-0098 (dose groups A/B/C received 50/150/450 μg for priming followed by three further administrations of 25/75/225 μg, respectively). Multiple T1D-related clinical parameters were also assessed to monitor disease progression and inform future development. Long-term follow-up to 48 weeks was also conducted in a subset of patients.. Treatment with IMCY-0098 was well tolerated with no systemic reactions; a total of 315 adverse events (AEs) were reported in 40 patients (97.6%) and were related to study treatment in 29 patients (68.3%). AEs were generally mild; no AE led to discontinuation of the study or death. No significant decline in C-peptide was noted from baseline to Week 24 for dose A, B, C, or placebo (mean change - 0.108, - 0.041, - 0.040, and - 0.012, respectively), suggesting no disease progression.. Promising safety profile and preliminary clinical response data support the design of a phase 2 study of IMCY-0098 in patients with recent-onset T1D.. IMCY-T1D-001: ClinicalTrials.gov NCT03272269; EudraCT: 2016-003514-27; and IMCY-T1D-002: ClinicalTrials.gov NCT04190693; EudraCT: 2018-003728-35. Topics: Adult; Autoimmunity; C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Disease Progression; Humans; Immunotherapy | 2023 |
In a recent randomized, multicenter trial (NCT02814838) a short-term anti-inflammatory treatment with ladarixin (LDX; an inhibitor of the CXCR1/2 chemokine receptors) did not show benefit on preserving residual beta cell function in new-onset type 1 diabetes. We present a. A double-blind, randomized (2:1), placebo-controlled study was conducted in 45 men and 31 women (aged 18-46 years) within 100 days of the first insulin administration. Patients received LDX (400 mg twice daily) for three cycles of 14 days on/14 days off, or placebo. The primary endpoint was the area under the curve for C-peptide [AUC (0-120 min)] in response to a 2-h mixed meal tolerance test (MMTT) at week 13 ± 1. Seventy-five patients completed the week 13 MMTT and were divided into three groups according to the DIR tertiles: lower, ≤ 0.23U/kg/die (n = 25); middle, 0.24-0.40 U/kg/die (n = 24); upper, ≥ 0.41 U/kg/die (n = 26).. When considering the patients in the upper tertile (HIGH-DIR), C-peptide AUC (0-120 min) at 13 weeks was higher in the LDX group (n = 16) than in the placebo (n = 10) group [difference: 0.72 nmol/L (95% CI 0.9-1.34), p = 0.027]. This difference reduced over time (0.71 nmol/L at 26 weeks, p = 0.04; 0.42 nmol/L at 52 weeks, p = 0.29), while it has never been significant at any time in patients in the lower and/or middle tertile (LOW-DIR). We characterized at baseline the HIGH-DIR and found that endo-metabolic (HOMA-B, adiponectin, and glucagon-to-C-peptide ratio) and immunologic (chemokine (C-C motif) ligand 2 (CCL2)/monocyte chemoattractant protein 1 (MCP1) and Vascular Endothelial Growth Factor (VEGF)) features distinguished this group from LOW-DIR.. While LDX did not prevent the progressive loss of beta-cell function in the majority of treated subjects, the Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Prospective Studies; Vascular Endothelial Growth Factor A | 2023 |
Pleconaril and ribavirin in new-onset type 1 diabetes: a phase 2 randomized trial.
Previous studies showed a low-grade enterovirus infection in the pancreatic islets of patients with newly diagnosed type 1 diabetes (T1D). In the Diabetes Virus Detection (DiViD) Intervention, a phase 2, placebo-controlled, randomized, parallel group, double-blind trial, 96 children and adolescents (aged 6-15 years) with new-onset T1D received antiviral treatment with pleconaril and ribavirin (n = 47) or placebo (n = 49) for 6 months, with the aim of preserving β cell function. The primary endpoint was the mean stimulated C-peptide area under the curve (AUC) 12 months after the initiation of treatment (less than 3 weeks after diagnosis) using a mixed linear model. The model used longitudinal log-transformed serum C-peptide AUCs at baseline, at 3 months, 6 months and 1 year. The primary endpoint was met with the serum C-peptide AUC being higher in the pleconaril and ribavirin treatment group compared to the placebo group at 12 months (average marginal effect = 0.057 in the linear mixed model; 95% confidence interval = 0.004-0.11, P = 0.037). The treatment was well tolerated. The results show that antiviral treatment may preserve residual insulin production in children and adolescent with new-onset T1D. This provides a rationale for further evaluating antiviral strategies in the prevention and treatment of T1D. European Union Drug Regulating Authorities Clinical Trials identifier: 2015-003350-41 . Topics: Adolescent; Antiviral Agents; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Humans; Ribavirin | 2023 |
Teplizumab and β-Cell Function in Newly Diagnosed Type 1 Diabetes.
Teplizumab, a humanized monoclonal antibody to CD3 on T cells, is approved by the Food and Drug Administration to delay the onset of clinical type 1 diabetes (stage 3) in patients 8 years of age or older with preclinical (stage 2) disease. Whether treatment with intravenous teplizumab in patients with newly diagnosed type 1 diabetes can prevent disease progression is unknown.. In this phase 3, randomized, placebo-controlled trial, we assessed β-cell preservation, clinical end points, and safety in children and adolescents who were assigned to receive teplizumab or placebo for two 12-day courses. The primary end point was the change from baseline in β-cell function, as measured by stimulated C-peptide levels at week 78. The key secondary end points were the insulin doses that were required to meet glycemic goals, glycated hemoglobin levels, time in the target glucose range, and clinically important hypoglycemic events.. Patients treated with teplizumab (217 patients) had significantly higher stimulated C-peptide levels than patients receiving placebo (111 patients) at week 78 (least-squares mean difference, 0.13 pmol per milliliter; 95% confidence interval [CI], 0.09 to 0.17; P<0.001), and 94.9% (95% CI, 89.5 to 97.6) of patients treated with teplizumab maintained a clinically meaningful peak C-peptide level of 0.2 pmol per milliliter or greater, as compared with 79.2% (95% CI, 67.7 to 87.4) of those receiving placebo. The groups did not differ significantly with regard to the key secondary end points. Adverse events occurred primarily in association with administration of teplizumab or placebo and included headache, gastrointestinal symptoms, rash, lymphopenia, and mild cytokine release syndrome.. Two 12-day courses of teplizumab in children and adolescents with newly diagnosed type 1 diabetes showed benefit with respect to the primary end point of preservation of β-cell function, but no significant differences between the groups were observed with respect to the secondary end points. (Funded by Provention Bio and Sanofi; PROTECT ClinicalTrials.gov number, NCT03875729.). Topics: Adolescent; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Humans; Hypoglycemic Agents | 2023 |
Baricitinib and β-Cell Function in Patients with New-Onset Type 1 Diabetes.
Janus kinase (JAK) inhibitors, including baricitinib, block cytokine signaling and are effective disease-modifying treatments for several autoimmune diseases. Whether baricitinib preserves β-cell function in type 1 diabetes is unclear.. In this phase 2, double-blind, randomized, placebo-controlled trial, we assigned patients with type 1 diabetes diagnosed during the previous 100 days to receive baricitinib (4 mg once per day) or matched placebo orally for 48 weeks. The primary outcome was the mean C-peptide level, determined from the area under the concentration-time curve, during a 2-hour mixed-meal tolerance test at week 48. Secondary outcomes included the change from baseline in the glycated hemoglobin level, the daily insulin dose, and measures of glycemic control assessed with the use of continuous glucose monitoring.. A total of 91 patients received baricitinib (60 patients) or placebo (31 patients). The median of the mixed-meal-stimulated mean C-peptide level at week 48 was 0.65 nmol per liter per minute (interquartile range, 0.31 to 0.82) in the baricitinib group and 0.43 nmol per liter per minute (interquartile range, 0.13 to 0.63) in the placebo group (P = 0.001). The mean daily insulin dose at 48 weeks was 0.41 U per kilogram of body weight per day (95% confidence interval [CI], 0.35 to 0.48) in the baricitinib group and 0.52 U per kilogram per day (95% CI, 0.44 to 0.60) in the placebo group. The levels of glycated hemoglobin were similar in the two trial groups. However, the mean coefficient of variation of the glucose level at 48 weeks, as measured by continuous glucose monitoring, was 29.6% (95% CI, 27.8 to 31.3) in the baricitinib group and 33.8% (95% CI, 31.5 to 36.2) in the placebo group. The frequency and severity of adverse events were similar in the two trial groups, and no serious adverse events were attributed to baricitinib or placebo.. In patients with type 1 diabetes of recent onset, daily treatment with baricitinib over 48 weeks appeared to preserve β-cell function as estimated by the mixed-meal-stimulated mean C-peptide level. (Funded by JDRF International and others; BANDIT Australian New Zealand Clinical Trials Registry number, ACTRN12620000239965.). Topics: Australia; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin | 2023 |
Intra-lymphatic administration of GAD-alum in type 1 diabetes: long-term follow-up and effect of a late booster dose (the DIAGNODE Extension trial).
To evaluate the long-term effect of intra-lymphatic administration of GAD-alum and a booster dose 2.5 years after the first intervention (DIAGNODE Extension study) in patients with recent-onset type 1 diabetes.. DIAGNODE-1: Samples were collected from 12 patients after 30 months who had received 3 injections of 4 μg GAD-alum into a lymph node with one-month interval. DIAGNODE Extension study: First in human, a fourth booster dose of autoantigen (GAD-alum) was given to 3 patients at 31.5 months, who were followed for another 12 months. C-peptide was measured during mixed meal tolerance tests (MMTTs). GADA, IA-2A, GADA subclasses, GAD. After 30-month treatment, efficacy was still seen in 8/12 patients (good responders, GR). Partial remission (IDAA1c < 9) had decreased compared to 15 months, but did not differ from baseline, and HbA1c remained stable. GAD. The effect of intra-lymphatic injections of GAD-alum had decreased after 30 months. Good responders showed a specific immune response. Administration of a fourth booster dose after 31.5 months was safe, and there was no decline in C-peptide observed during the 12-month follow-up. Topics: Alum Compounds; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Immunoglobulin G | 2022 |
Combined therapy with CD4
Monotherapy with autologous expanded CD4. We conducted a three-arms clinical trial to explore the efficacy and safety of the combined treatment with Tregs and rituximab in paediatric patients with T1DM. The patients were allocated to three groups: Tregs only (n = 13), Tregs + rituximab (n = 12) and control (n = 11). The key primary efficacy analyses were C-peptide levels (mixed meal tolerance test) and the proportion of patients in remission at 12 and 24 months.. At month 24, as compared with the control, both treatment groups remained superior in the area under the curve of C-peptide mixed meal tolerance test, whereas in the analysis of all visits only the combined therapy improved area under the curve at 12 and 24 months. The proportion of patients in remission was significantly higher in the combined group than in the control group at 3, 6, 9 and 21 months but not at 18 and 24 months. There was no significant difference between the Tregs only group and control group. Adverse events occurred in 80% patients, mostly in the combined group and Tregs only group. No adverse events led to the withdrawal of the intervention or death. All comparisons were performed with alpha level of 5%.. Over 2 years, combined therapy with Tregs and rituximab was consistently superior to monotherapy in delaying T1DM progression in terms of C-peptide levels and the maintenance of remission. Topics: C-Peptide; Child; Combined Modality Therapy; Diabetes Mellitus, Type 1; Humans; Rituximab; T-Lymphocytes, Regulatory | 2022 |
Ladarixin, an inhibitor of the interleukin-8 receptors CXCR1 and CXCR2, in new-onset type 1 diabetes: A multicentre, randomized, double-blind, placebo-controlled trial.
To evaluate the ability of ladarixin (LDX, 400 mg twice-daily for three cycles of 14 days on/14 days off), an inhibitor of the CXCR1/2 chemokine receptors, to maintain C-peptide production in adult patients with newly diagnosed type 1 diabetes.. A double-blind, randomized (2:1), placebo-controlled study was conducted in 45 males and 31 females (aged 18-46 years) within 100 days of the first insulin administration. The primary endpoint was the area under the curve (AUC) for C-peptide in response to a 2-hour mixed meal tolerance test (AUC. In newly diagnosed patients with type 1 diabetes, short-term LDX treatment had no appreciable effect on preserving residual beta cell function. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Receptors, Interleukin-8; Sulfonamides; Treatment Outcome | 2022 |
Investigating the efficacy of baricitinib in new onset type 1 diabetes mellitus (BANDIT)-study protocol for a phase 2, randomized, placebo controlled trial.
Type 1 diabetes (T1D) places an extraordinary burden on individuals and their families, as well as on the healthcare system. Despite recent advances in glucose sensors and insulin pump technology, only a minority of patients meet their glucose targets and face the risk of both acute and long-term complications, some of which are life-threatening. The JAK-STAT pathway is critical for the immune-mediated pancreatic beta cell destruction in T1D. Our pre-clinical data show that inhibitors of JAK1/JAK2 prevent diabetes and reverse newly diagnosed diabetes in the T1D non-obese diabetic mouse model. The goal of this study is to determine if the JAK1/JAK2 inhibitor baricitinib impairs type 1 diabetes autoimmunity and preserves beta cell function.. This will be as a multicentre, two-arm, double-blind, placebo-controlled randomized trial in individuals aged 10-30 years with recent-onset T1D. Eighty-three participants will be randomized in a 2:1 ratio within 100 days of diagnosis to receive either baricitinib 4mg/day or placebo for 48 weeks and then monitored for a further 48 weeks after stopping study drug. The primary outcome is the plasma C-peptide 2h area under the curve following ingestion of a mixed meal. Secondary outcomes include HbA1c, insulin dose, continuous glucose profile and adverse events. Mechanistic assessments will characterize general and diabetes-specific immune responses.. This study will determine if baricitinib slows the progressive, immune-mediated loss of beta cell function that occurs after clinical presentation of T1D. Preservation of beta cell function would be expected to improve glucose control and prevent diabetes complications, and justify additional trials of baricitinib combined with other therapies and of its use in at-risk populations to prevent T1D.. ANZCTR ACTRN12620000239965 . Registered on 26 February 2020.. gov NCT04774224. Registered on 01 March 2021. Topics: Animals; Azetidines; C-Peptide; Clinical Trials, Phase II as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Glucose; Humans; Janus Kinases; Mice; Multicenter Studies as Topic; Purines; Pyrazoles; Randomized Controlled Trials as Topic; Signal Transduction; STAT Transcription Factors; Sulfonamides; Treatment Outcome | 2022 |
Intralymphatic GAD-Alum (Diamyd®) Improves Glycemic Control in Type 1 Diabetes With HLA DR3-DQ2.
Residual beta cell function in type 1 diabetes (T1D) is associated with lower risk of complications. Autoantigen therapy with GAD-alum (Diamyd) given in 3 intralymphatic injections with oral vitamin D has shown promising results in persons with T1D carrying the human leukocyte antigen (HLA) DR3-DQ2 haplotype in the phase 2b trial DIAGNODE-2. We aimed to explore the efficacy of intralymphatic GAD-alum on blood glucose recorded by continuous glucose monitoring (CGM).. DIAGNODE-2 (NCT03345004) was a multicenter, randomized, placebo-controlled, double-blind trial of 109 recent-onset T1D patients aged 12 to 24 years with GAD65 antibodies and fasting C-peptide > 0.12 nmol/L, which randomized patients to 3 intralymphatic injections of 4 μg GAD-alum and oral vitamin D, or placebo. We report results for exploratory endpoints assessed by 14-day CGM at months 0, 6, and 15. Treatment arms were compared by mixed-effects models for repeated measures adjusting for baseline values.. We included 98 patients with CGM recordings of sufficient quality (DR3-DQ2-positive patients: 27 GAD-alum-treated and 15 placebo-treated). In DR3-DQ2-positive patients, percent of time in range (TIR, 3.9-10 mmol/L) declined less between baseline and month 15 in GAD-alum-treated compared with placebo-treated patients (-5.1% and -16.7%, respectively; P = 0.0075), with reduced time > 13.9 mmol/L (P = 0.0036), and significant benefits on the glucose management indicator (P = 0.0025). No differences were detected for hypoglycemia. GAD-alum compared to placebo lowered the increase in glycemic variability (standard deviation) observed in both groups (P = 0.0219). Change in C-peptide was correlated with the change in TIR.. Intralymphatic GAD-alum improves glycemic control in recently diagnosed T1D patients carrying HLA DR3-DQ2. Topics: Adolescent; Alum Compounds; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Glycemic Control; HLA-DR3 Antigen; Humans; Vitamin D; Young Adult | 2022 |
Effect of Liraglutide Treatment on Whole-body Glucose Fluxes in C-peptide-Positive Type 1 Diabetes During Hypoglycemia.
The effect of liraglutide in C-peptide-positive (C-pos) type 1 diabetes (T1D) patients during hypoglycemia remains unclear.. To investigate the effect of a 12-week liraglutide treatment on the body glucose fluxes during a hypoglycemic clamp in C-pos T1D patients and its impact on the alpha- and beta-cell responses during hypoglycemia.. This was a randomized, double-blind, crossover study. Each C-pos T1D patient was allocated to the treatment sequence liraglutide/placebo or placebo/liraglutide with daily injections for 12 weeks adjunct to insulin treatment, separated by a 4-week washout period.. Fourteen T1D patients with fasting C-peptide ≥ 0.1 nmol/L.. All patients underwent a hyperinsulinemic-stepwise-hypoglycemic clamp with isotope tracer [plasma glucose (PG) plateaus: 5.5, 3.5, 2.5, and 3.9 mmol/L] after a 3-month liraglutide (1.2 mg) or placebo treatment.. The responses of endogenous glucose production (EGP) and rate of peripheral glucose disposal (Rd) were similar for liraglutide and placebo treatment during the clamp.. The numbers of hypoglycemic events were similar in both groups. At the clamp, mean glucagon levels were significantly lower at PG plateau 5.5 mmol/L in the liraglutide than in the placebo group but showed similar responses to hypoglycemia in both groups. Mean C-peptide levels were significantly higher at PG-plateaus 5.5 and 3.5 mmol/L after liraglutide treatment, but this effect was not reflected in EGP and Rd. Hemoglobin A1c and body weight were lower, and a trend for reduced insulin was seen after liraglutide treatment.. The results indicate that 3 months of liraglutide treatment does not promote or prolong hypoglycemia in C-pos T1D patients. Topics: Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Glucose; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Liraglutide; Treatment Outcome | 2022 |
Closed-Loop Therapy and Preservation of C-Peptide Secretion in Type 1 Diabetes.
Whether improved glucose control with hybrid closed-loop therapy can preserve C-peptide secretion as compared with standard insulin therapy in persons with new-onset type 1 diabetes is unclear.. In a multicenter, open-label, parallel-group, randomized trial, we assigned youths 10.0 to 16.9 years of age within 21 days after a diagnosis of type 1 diabetes to receive hybrid closed-loop therapy or standard insulin therapy (control) for 24 months. The primary end point was the area under the curve (AUC) for the plasma C-peptide level (after a mixed-meal tolerance test) at 12 months after diagnosis. The analysis was performed on an intention-to-treat basis.. A total of 97 participants (mean [±SD] age, 12±2 years) underwent randomization: 51 were assigned to receive closed-loop therapy and 46 to receive control therapy. The AUC for the C-peptide level at 12 months (primary end point) did not differ significantly between the two groups (geometric mean, 0.35 pmol per milliliter [interquartile range, 0.16 to 0.49] with closed-loop therapy and 0.46 pmol per milliliter [interquartile range, 0.22 to 0.69] with control therapy; mean adjusted difference, -0.06 pmol per milliliter [95% confidence interval {CI}, -0.14 to 0.03]). There was not a substantial between-group difference in the AUC for the C-peptide level at 24 months (geometric mean, 0.18 pmol per milliliter [interquartile range, 0.06 to 0.22] with closed-loop therapy and 0.24 pmol per milliliter [interquartile range, 0.05 to 0.30] with control therapy; mean adjusted difference, -0.04 pmol per milliliter [95% CI, -0.14 to 0.06]). The arithmetic mean glycated hemoglobin level was lower in the closed-loop group than in the control group by 4 mmol per mole (0.4 percentage points; 95% CI, 0 to 8 mmol per mole [0.0 to 0.7 percentage points]) at 12 months and by 11 mmol per mole (1.0 percentage points; 95% CI, 7 to 15 mmol per mole [0.5 to 1.5 percentage points]) at 24 months. Five cases of severe hypoglycemia occurred in the closed-loop group (in 3 participants), and one occurred in the control group; one case of diabetic ketoacidosis occurred in the closed-loop group.. In youths with new-onset type 1 diabetes, intensive glucose control for 24 months did not appear to prevent the decline in residual C-peptide secretion. (Funded by the National Institute for Health and Care Research and others; CLOuD ClinicalTrials.gov number, NCT02871089.). Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Hypoglycemic Agents; Insulin; Insulin Infusion Systems | 2022 |
Phase III, randomised, double-blind, placebo-controlled, multicentre trial to evaluate the efficacy and safety of rhGAD65 to preserve endogenous beta cell function in adolescents and adults with recently diagnosed type 1 diabetes, carrying the genetic HLA
Type 1 diabetes (T1D) is an autoimmune disease leading to the destruction of the insulin-producing beta cells resulting in insulin deficiency and hyperglycaemic. Today, no approved therapy exists to halt this detrimental immunologic process. In a recent phase 2b study, intralymphatic administration of recombinant human glutamic acid decarboxylase 65 kDa (rhGAD65) adsorbed to Alhydrogel adjuvant to individuals recently diagnosed with T1D and carrying the HLA DR3-DQ2 haplotype showed promising results in preserving endogenous insulin secretion, confirming the results of a large meta-analysis of three randomised placebo-controlled trials of subcutaneous rhGAD65. The aim of the current precision medicine phase 3 study is to determine whether intralymphatic administration of rhGAD65 preserves insulin secretion and improves glycaemic control in presumed responder individuals with recently diagnosed T1D carrying HLA DR3-DQ2.. The trial is approved by Ethics Committees in Poland (124/2021), the Netherlands (R21.089), Sweden (2021-05063), Czech Republic (EK-1144/21), Germany (2021361) and Spain (21/2021). Results will be published in international peer-reviewed scientific journals and presented at national and international conferences.. EudraCT identifier: 2021-002731-32, NCT identifier: NCT05018585. Topics: Adolescent; Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Clinical Trials, Phase III as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Haplotypes; HLA-DR3 Antigen; Humans; Insulin; Meta-Analysis as Topic; Multicenter Studies as Topic; Randomized Controlled Trials as Topic; Young Adult | 2022 |
Effects of Dietary Fat and Protein on Glucoregulatory Hormones in Adolescents and Young Adults With Type 1 Diabetes.
Dietary fat and protein impact postprandial hyperglycemia in people with type 1 diabetes, but the underlying mechanisms are poorly understood. Glucoregulatory hormones are also known to modulate gastric emptying and may contribute to this effect.. Investigate the effects of fat and protein on glucagon-like peptide (GLP-1), glucagon-dependent insulinotropic polypeptide (GIP) and glucagon secretion.. 2 crossover euglycemic insulin clamp clinical trials at 2 Australian pediatric diabetes centers. Participants were 12-21 years (n = 21) with type 1 diabetes for ≥1 year. Participants consumed a low-protein (LP) or high-protein (HP) meal in Study 1, and low-protein/low-fat (LPLF) or high-protein/high-fat (HPHF) meal in Study 2, all containing 30 g of carbohydrate. An insulin clamp was used to maintain postprandial euglycemia and plasma glucoregulatory hormones were measured every 30 minutes for 5 hours. Data from both cohorts (n = 11, 10) were analyzed separately. The main outcome measure was area under the curve of GLP-1, GIP, and glucagon.. Meals low in fat and protein had minimal effect on GLP-1, while there was sustained elevation after HP (80.3 ± 16.8 pmol/L) vs LP (56.9 ± 18.6), P = .016, and HPHF (103.0 ± 26.9) vs LPLF (69.5 ± 31.9) meals, P = .002. The prompt rise in GIP after all meals was greater after HP (190.2 ± 35.7 pmol/L) vs LP (152.3 ± 23.3), P = .003, and HPHF (258.6 ± 31.0) vs LPLF (151.7 ± 29.4), P < .001. A rise in glucagon was also seen in response to protein, and HP (292.5 ± 88.1 pg/mL) vs LP (182.8 ± 48.5), P = .010.. The impact of fat and protein on postprandial glucose excursions may be mediated by the differential secretion of glucoregulatory hormones. Further studies to better understand these mechanisms may lead to improved personalized postprandial glucose management. Topics: Adult; Australia; Biomarkers; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Dietary Fats; Dietary Proteins; Female; Follow-Up Studies; Gastric Emptying; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Humans; Hyperglycemia; Insulin; Male; Meals; Prognosis | 2022 |
Phase II multicentre, double-blind, randomised trial of ustekinumab in adolescents with new-onset type 1 diabetes (USTEK1D): trial protocol.
Most individuals newly diagnosed with type 1 diabetes (T1D) have 10%-20% of beta-cell function remaining at the time of diagnosis. Preservation of residual beta-cell function at diagnosis may improve glycaemic control and reduce longer-term complications.Immunotherapy has the potential to preserve endogenous beta-cell function and thereby improve metabolic control even in poorly compliant individuals. We propose to test ustekinumab (STELARA), a targeted and well-tolerated therapy that may halt T-cell and cytokine-mediated destruction of beta-cells in the pancreas at the time of diagnosis.. This is a double-blind phase II study to assess the safety and efficacy of ustekinumab in 72 children and adolescents aged 12-18 with new-onset T1D.Participants should have evidence of residual functioning beta-cells (serum C-peptide level >0.2nmol/L in the mixed-meal tolerance test (MMTT) and be positive for at least one islet autoantibody (GAD, IA-2, ZnT8) to be eligible.Participants will be given ustekinumab/placebo subcutaneously at weeks 0, 4 and 12, 20, 28, 36 and 44 in a dose depending on the body weight and will be followed for 12 months after dose 1.MMTTs will be used to measure the efficacy of ustekinumab for preserving C-peptide area under the curve at week 52 compared with placebo. Secondary objectives include further investigations into the efficacy and safety of ustekinumab, patient and parent questionnaires, alternative methods for measuring insulin production and exploratory mechanistic work.. This trial received research ethics approval from the Wales Research Ethics Committee 3 in September 2018 and began recruiting in December 2018.The results will be disseminated using highly accessed, peer-reviewed medical journals and presented at conferences.. ISRCTN14274380. Topics: Adolescent; C-Peptide; Clinical Trials, Phase II as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Humans; Insulin; Multicenter Studies as Topic; Randomized Controlled Trials as Topic; Treatment Outcome; Ustekinumab | 2021 |
Implanted pluripotent stem-cell-derived pancreatic endoderm cells secrete glucose-responsive C-peptide in patients with type 1 diabetes.
An open-label, first-in-human phase 1/2 study is being conducted to evaluate the safety and efficacy of pancreatic endoderm cells (PECs) implanted in non-immunoprotective macroencapsulation devices for the treatment of type 1 diabetes. We report an analysis on 1 year of data from the first cohort of 15 patients from a single trial site that received subcutaneous implantation of cell products combined with an immunosuppressive regimen. Implants were well tolerated with no teratoma formation or severe graft-related adverse events. After implantation, patients had increased fasting C-peptide levels and increased glucose-responsive C-peptide levels and developed mixed meal-stimulated C-peptide secretion. There were immunosuppression-related transient increases in circulating regulatory T cells, PD1 Topics: C-Peptide; Cell Differentiation; Diabetes Mellitus, Type 1; Endoderm; Glucose; Humans; Insulin; Insulin-Secreting Cells | 2021 |
Insulin expression and C-peptide in type 1 diabetes subjects implanted with stem cell-derived pancreatic endoderm cells in an encapsulation device.
These preliminary data from an ongoing first-in-human phase 1/2, open-label study provide proof-of-concept that pluripotent stem cell-derived pancreatic endoderm cells (PEC-01) engrafted in type 1 diabetes patients become islet cells releasing insulin in a physiologically regulated fashion. In this study of 17 subjects aged 22-57 with type 1 diabetes, PEC-01 cells were implanted subcutaneously in VC-02 macroencapsulation devices, allowing for direct vascularization of the cells. Engraftment and insulin expression were observed in 63% of VC-02 units explanted from subjects at 3-12 months post-implant. Six of 17 subjects (35.3%) demonstrated positive C-peptide as early as 6 months post-implant. Most reported adverse events were related to surgical implant or explant procedures (27.9%) or to side-effects of immunosuppression (33.7%). Initial data suggest that pluripotent stem cells, which can be propagated to the desired biomass and differentiated into pancreatic islet-like tissue, may offer a scalable, renewable alternative to pancreatic islet transplants. Topics: Adolescent; Adult; Aged; C-Peptide; Cells, Immobilized; Diabetes Mellitus, Type 1; Endoderm; Female; Humans; Insulin; Male; Middle Aged; Pancreas; Stem Cell Transplantation; Stem Cells; Young Adult | 2021 |
Faecal microbiota transplantation halts progression of human new-onset type 1 diabetes in a randomised controlled trial.
Type 1 diabetes (T1D) is characterised by islet autoimmunity and beta cell destruction. A gut microbiota-immunological interplay is involved in the pathophysiology of T1D. We studied microbiota-mediated effects on disease progression in patients with type 1 diabetes using faecal microbiota transplantation (FMT).. Patients with recent-onset (<6 weeks) T1D (18-30 years of age) were randomised into two groups to receive three autologous or allogenic (healthy donor) FMTs over a period of 4 months. Our primary endpoint was preservation of stimulated C peptide release assessed by mixed-meal tests during 12 months. Secondary outcome parameters were changes in glycaemic control, fasting plasma metabolites, T cell autoimmunity, small intestinal gene expression profile and intestinal microbiota composition.. Stimulated C peptide levels were significantly preserved in the autologous FMT group (n=10 subjects) compared with healthy donor FMT group (n=10 subjects) at 12 months. Small intestinal. FMT halts decline in endogenous insulin production in recently diagnosed patients with T1D in 12 months after disease onset. Several microbiota-derived plasma metabolites and bacterial strains were linked to preserved residual beta cell function. This study provides insight into the role of the intestinal gut microbiome in T1D.. NTR3697. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Duodenum; Fecal Microbiota Transplantation; Female; Gastrointestinal Microbiome; Humans; Insulin-Secreting Cells; Male; Transplantation, Autologous; Young Adult | 2021 |
A randomised, single-blind, placebo-controlled, dose-finding safety and tolerability study of the anti-CD3 monoclonal antibody otelixizumab in new-onset type 1 diabetes.
Numerous clinical studies have investigated the anti-CD3ɛ monoclonal antibody otelixizumab in individuals with type 1 diabetes, but limited progress has been made in identifying the optimal clinical dose with acceptable tolerability and safety. The aim of this study was to evaluate the association between dose-response, safety and tolerability, beta cell function preservation and the immunological effects of otelixizumab in new-onset type 1 diabetes.. In this randomised, single-blind, placebo-controlled, 24 month study, conducted in five centres in Belgium via the Belgian Diabetes Registry, participants (16-27 years old, <32 days from diagnosis of type 1 diabetes) were scheduled to receive placebo or otelixizumab in one of four dose cohorts (cumulative i.v. dose 9, 18, 27 or 36 mg over 6 days; planned n = 40). Randomisation to treatment was by a central computer system; only participants and bedside study personnel were blinded to study treatment. The co-primary endpoints were the incidence of adverse events, the rate of Epstein-Barr virus (EBV) reactivation, and laboratory measures and vital signs. A mixed-meal tolerance test was used to assess beta cell function; exploratory biomarkers were used to measure T cell responses.. Thirty participants were randomised/28 were analysed (placebo, n = 6/5; otelixizumab 9 mg, n = 9/8; otelixizumab 18 mg, n = 8/8; otelixizumab 27 mg, n = 7/7; otelixizumab 36 mg, n = 0). Dosing was stopped at otelixizumab 27 mg as the predefined EBV reactivation stopping criteria were met. Adverse event frequency and severity were dose dependent; all participants on otelixizumab experienced at least one adverse event related to cytokine release syndrome during the dosing period. EBV reactivation (otelixizumab 9 mg, n = 2/9; 18 mg, n = 4/8: 27 mg, n = 5/7) and clinical manifestations (otelixizumab 9 mg, n = 0/9; 18 mg, n = 1/8; 27 mg, n = 3/7) were rapid, dose dependent and transient, and were associated with increased productive T cell clonality that diminished over time. Change from baseline mixed-meal tolerance test C-peptide weighted mean AUC. A metabolic response was observed with otelixizumab 9 mg, while doses higher than 18 mg increased the risk of unwanted clinical EBV reactivation. Although otelixizumab can temporarily compromise immunocompetence, allowing EBV to reactivate, the effect is dose dependent and transient, as evidenced by a rapid emergence of EBV-specific T cells preceding long-term control over EBV reactivation.. ClinicalTrials.gov NCT02000817.. The study was funded by GlaxoSmithKline. Graphical abstract. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Epstein-Barr Virus Infections; Female; Humans; Insulin Secretion; Insulin-Secreting Cells; Latent Infection; Male; Single-Blind Method; Young Adult | 2021 |
Human plasma-derived alpha
While circulating levels of alpha. Seventy-six participants (aged 6-35 years) were randomized at 25 centers within 3 months of T1DM diagnosis.. Infusions were well tolerated with no new safety signals. All groups exhibited highly variable declines in the primary outcome measure at 52 weeks with no statistically significant difference from placebo. Interleukin-6 (IL-6) was reduced from baseline in all alpha. Pharmacologic therapy with alpha Topics: Adolescent; Adult; alpha 1-Antitrypsin; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Infusions, Intravenous; Interleukin-6; Male; Proof of Concept Study; Serine Proteinase Inhibitors; Treatment Outcome; Young Adult | 2021 |
Exhausted-like CD8+ T cell phenotypes linked to C-peptide preservation in alefacept-treated T1D subjects.
Clinical trials of biologic therapies in type 1 diabetes (T1D) aim to mitigate autoimmune destruction of pancreatic β cells through immune perturbation and serve as resources to elucidate immunological mechanisms in health and disease. In the T1DAL trial of alefacept (LFA3-Ig) in recent-onset T1D, endogenous insulin production was preserved in 30% of subjects for 2 years after therapy. Given our previous findings linking exhausted-like CD8+ T cells to beneficial response in T1D trials, we applied unbiased analyses to sorted CD8+ T cells to evaluate their potential role in T1DAL. Using RNA sequencing, we found that greater insulin C-peptide preservation was associated with a module of activation- and exhaustion-associated genes. This signature was dissected into 2 CD8 memory phenotypes through correlation with cytometry data. These cells were hypoproliferative, shared expanded rearranged TCR junctions, and expressed exhaustion-associated markers including TIGIT and KLRG1. The 2 phenotypes could be distinguished by reciprocal expression of CD8+ T and NK cell markers (GZMB, CD57, and inhibitory killer cell immunoglobulin-like receptor [iKIR] genes), versus T cell activation and differentiation markers (PD-1 and CD28). These findings support previous evidence linking exhausted-like CD8+ T cells to successful immune interventions for T1D, while suggesting that multiple inhibitory mechanisms can promote this beneficial cell state. Topics: Adolescent; Adult; Alefacept; C-Peptide; CD57 Antigens; CD8-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Humans; Immunologic Factors; Immunologic Memory; Immunophenotyping; Killer Cells, Natural; Lectins, C-Type; Lymphocyte Activation; Male; Programmed Cell Death 1 Receptor; Receptors, Immunologic; RNA-Seq; Young Adult | 2021 |
Residual β cell function in long-term type 1 diabetes associates with reduced incidence of hypoglycemia.
BACKGROUNDWe investigated residual β cell function in Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study participants with an average 35-year duration of type 1 diabetes mellitus (T1DM).METHODSSerum C-peptide was measured during a 4-hour mixed-meal tolerance test. Associations with metabolic outcomes and complications were explored among nonresponders (all C-peptide values after meal <0.003 nmol/L) and 3 categories of responders, classified by peak C-peptide concentration (nmol/L) as high (>0.2), intermediate (>0.03 to ≤0.2), and low (≥ 0.003 to ≤0.03).RESULTSOf the 944 participants, 117 (12.4%) were classified as responders. Residual C-peptide concentrations were associated with higher DCCT baseline concentrations of stimulated C-peptide (P value for trend = 0.0001). Residual C-peptide secretion was not associated with current or mean HbA1c, HLA high-risk haplotypes for T1DM, or the current presence of T1DM autoantibodies. The proportion of subjects with a history of severe hypoglycemia was lower with high (27%) and intermediate (48%) residual C-peptide concentrations than with low (74%) and no (70%) residual C-peptide concentrations (P value for trend = 0.0001). Responders and nonresponders demonstrated similar rates of advanced microvascular complications.CONCLUSIONβ Cell function can persist in long-duration T1DM. With a peak C-peptide concentration of >0.03 nmol/L, we observed clinically meaningful reductions in the prevalence of severe hypoglycemia.TRIAL REGISTRATIONClinicalTrials.gov NCT00360815 and NCT00360893.FUNDINGDivision of Diabetes Endocrinology and Metabolic Diseases of the National Institute of Diabetes and Digestive and Kidney Diseases (DP3-DK104438, U01 DK094176, and U01 DK094157). Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Incidence; Insulin-Secreting Cells; Male; Middle Aged | 2021 |
Intralymphatic Glutamic Acid Decarboxylase With Vitamin D Supplementation in Recent-Onset Type 1 Diabetes: A Double-Blind, Randomized, Placebo-Controlled Phase IIb Trial.
To evaluate the efficacy of aluminum-formulated intralymphatic glutamic acid decarboxylase (GAD-alum) therapy combined with vitamin D supplementation in preserving endogenous insulin secretion in all patients with type 1 diabetes (T1D) or in a genetically prespecified subgroup.. In a multicenter, randomized, placebo-controlled, double-blind trial, 109 patients aged 12-24 years (mean ± SD 16.4 ± 4.1) with a diabetes duration of 7-193 days (88.8 ± 51.4), elevated serum GAD65 autoantibodies, and a fasting serum C-peptide >0.12 nmol/L were recruited. Participants were randomized to receive either three intralymphatic injections (1 month apart) with 4 μg GAD-alum and oral vitamin D (2,000 IE daily for 120 days) or placebo. The primary outcome was the change in stimulated serum C-peptide (mean area under the curve [AUC] after a mixed-meal tolerance test) between baseline and 15 months.. Primary end point was not met in the full analysis set (treatment effect ratio 1.091 [CI 0.845-1.408];. Intralymphatic administration of GAD-alum is a simple, well-tolerated treatment that together with vitamin D supplementation seems to preserve C-peptide in patients with recent-onset T1D carrying HLA DR3-DQ2. This constitutes a disease-modifying treatment for T1D with a precision medicine approach. Topics: C-Peptide; Diabetes Mellitus, Type 1; Dietary Supplements; Double-Blind Method; Glutamate Decarboxylase; Humans; Vitamin D | 2021 |
Pancreatic β-Cell Function Is Associated with Augmented Counterregulation to In-Exercise Hypoglycemia in Type 1 Diabetes.
This study aimed to investigate the influence of residual β-cell function on counterregulatory hormonal responses to hypoglycemia during acute physical exercise in people with type 1 diabetes (T1D). A secondary aim was to explore relationships between biomarkers of pancreatic β-cell function and indices of glycemia following acute exercise including the nocturnal period.. This study involved an exploratory, secondary analysis of data from individuals with T1D who partook in a four-peroid, randomized, cross-over trial involving a bout of evening exercise followed by an overnight stay in a clinical laboratory facility. Participants were split into two groups: (i) a stimulated C-peptide level of ≥30 pmol⋅L-1 (low-level secretors [LLS], n = 6) or (ii) <30 pmol⋅L-1 (microsecretors [MS], n = 10). Pancreatic hormones (C-peptide, proinsulin, and glucagon), catecholamines (epinephrine [EPI] and norepinephrine [NE]), and metabolic biomarkers (blood glucose, blood lactate, and β-hydroxybutyrate) were measured at rest, during exercise with and without a hypoglycemic (blood glucose ≤3.9 mmol⋅L-1) episode, and throughout a 13-h postexercise period. Interstitial glucose monitoring was used to assess indices of glycemic variability.. During in-exercise hypoglycemia, LLS presented with greater sympathoadrenal (EPI and NE P ≤ 0.05) and ketone (P < 0.01) concentrations. Glucagon remained similar (P = 0.09). Over exercise, LLS experienced larger drops in C-peptide and proinsulin (both P < 0.01) as well as greater increases in EPI (P < 0.01) and β-hydroxybutyrate (P = 0.03). LLS spent less time in the interstitial-derived hypoglycemic range acutely postexercise and had lower glucose variability throughout the nocturnal period.. Higher residual β-cell function was associated with greater sympathoadrenal and ketonic responses to exercise-induced hypoglycemia as well as improved glycemia leading into and throughout the nocturnal hours. Even a minimal amount of residual β-cell function confers a beneficial effect on glycemic outcomes during and after exercise in people with T1D. Topics: Adult; Biomarkers; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Exercise; Female; Glucagon; Humans; Hypoglycemia; Insulin-Secreting Cells; Male; Middle Aged; Young Adult | 2021 |
A high potency multi-strain probiotic improves glycemic control in children with new-onset type 1 diabetes mellitus: A randomized, double-blind, and placebo-controlled pilot study.
Studies in animal models and humans with type 1 diabetes mellitus (T1DM) have shown that probiotic supplementation leads to decreased pro-inflammatory cytokines (responsible for damaging β-cells of the pancreas), improved gut barrier function, and induction of immune tolerance.. To study the effect of supplementation of probiotics in children with T1DM on glycemic control, insulin dose, and plasma C-peptide levels.. A single-centered, double-blinded, and randomized placebo-controlled pilot trial was conducted in children (2-12 years) with new-onset T1DM. Ninety-six children were randomized and allocated to Placebo or Intervention groups. The intervention included high dose (112.5 billion viable lyophilized bacteria per capsule) multi-strain probiotic De Simone formulation (manufactured by Danisco-Dupont) sold as Visbiome® in India. The probiotic was supplemented for 3 months and HbA1c, fasting C-peptide, blood sugar records, and insulin dose was recorded at baseline and 3 months.. A total of 90 patients (45 in each group) were analyzed for outcome parameters. We found a significant decrease in HbA1c (5.1 vs. 3.8; p = 0.021) and a significant decline in total and bolus insulin dose (U/kg/day; p = 0.037 and 0.018, respectively) in the intervention group when compared with the placebo group. A significantly higher (p = 0.023) number of children achieved remission in the treatment group. We did not notice adverse effects in either of the study groups.. Children with newly diagnosed T1DM managed with standard treatment along with probiotics showed better glycemic control and a decrease in insulin requirements; however, more extensive studies are further warranted. Topics: C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Dietary Supplements; Double-Blind Method; Female; Glycated Hemoglobin; Glycemic Control; Humans; Insulin; Male; Pilot Projects; Probiotics | 2021 |
Proinsulin to C-Peptide Ratio in the First Year After Diagnosis of Type 1 Diabetes.
The proinsulin to C-peptide (PI:C) ratio is reputedly a biomarker of β-cell endoplasmic reticulum (ER) stress.. This study examined the natural history of the PI:C ratio and its correlation with residual β-cell function in childhood new-onset type 1 diabetes (T1D). Over the first year of T1D, the temporal trend in fasting and nutrient-stimulated PI data is limited.. PI was a secondary pre-planned analysis of our 1-year, randomized, double-blind, placebo-controlled gamma aminobutyric acid (GABA) trial in new-onset T1D. Of the 99 participants in the primary study, aged 4 to 18 years, 30 were placebo. This study only involved the 30 placebo patients; all were enrolled within 5 weeks of T1D diagnosis. A liquid mixed meal tolerance test was administered at baseline and 5 and 12 months for determination of C-peptide, PI, glucose, and hemoglobin A1C.. Both the fasting (P = 0.0003) and stimulated (P = 0.00008) PI:C ratios increased from baseline to 12 months, indicating escalating β-cell ER stress. The baseline fasting PI correlated with the fasting change in C-peptide at 12 months (P = 0.004) with a higher PI correlating with greater decline in C-peptide. Patients with an insulin-adjusted A1C >9% (hence, not in remission) had higher fasting PI:C ratios. Younger age at diagnosis correlated with a higher PI:C ratio (P = 0.04).. Children with new-onset T1D undergo progressive β-cell ER stress and aberrant proinsulin processing, as evidenced by increasing PI:C ratios. Moreover, the PI:C ratio reflects more aggressive β-cell onslaught with younger age, as well as diminished glycemic control. Topics: Adolescent; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Endoplasmic Reticulum Stress; Fasting; Female; Glucose Tolerance Test; Glycemic Control; Humans; Insulin; Insulin-Secreting Cells; Male; Meals; Placebos; Proinsulin | 2021 |
The effect of low-dose IL-2 and Treg adoptive cell therapy in patients with type 1 diabetes.
BACKGROUNDA previous phase I study showed that the infusion of autologous Tregs expanded ex vivo into patients with recent-onset type 1 diabetes (T1D) had an excellent safety profile. However, the majority of the infused Tregs were undetectable in the peripheral blood 3 months postinfusion (Treg-T1D trial). Therefore, we conducted a phase I study (TILT trial) combining polyclonal Tregs and low-dose IL-2, shown to enhance Treg survival and expansion, and assessed the impact over time on Treg populations and other immune cells.METHODSPatients with T1D were treated with a single infusion of autologous polyclonal Tregs followed by one or two 5-day courses of recombinant human low-dose IL-2 (ld-IL-2). Flow cytometry, cytometry by time of flight, and 10x Genomics single-cell RNA-Seq were used to follow the distinct immune cell populations' phenotypes over time.RESULTSMultiparametric analysis revealed that the combination therapy led to an increase in the number of infused and endogenous Tregs but also resulted in a substantial increase from baseline in a subset of activated NK, mucosal associated invariant T, and clonal CD8+ T cell populations.CONCLUSIONThese data support the hypothesis that ld-IL-2 expands exogenously administered Tregs but also can expand cytotoxic cells. These results have important implications for the use of a combination of ld-IL-2 and Tregs for the treatment of autoimmune diseases with preexisting active immunity.TRIAL REGISTRATIONClinicalTrials.gov NCT01210664 (Treg-T1D trial), NCT02772679 (TILT trial).FUNDINGSean N. Parker Autoimmune Research Laboratory Fund, National Center for Research Resources. Topics: Adult; C-Peptide; CD8-Positive T-Lymphocytes; Cell Survival; Combined Modality Therapy; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunotherapy, Adoptive; Insulin; Interleukin-2; Lymphocyte Count; Male; Natural Killer T-Cells; Recombinant Proteins; T-Lymphocytes, Regulatory; Time Factors; Transcriptome; Young Adult | 2021 |
Time to Peak Glucose and Peak C-Peptide During the Progression to Type 1 Diabetes in the Diabetes Prevention Trial and TrialNet Cohorts.
To assess the progression of type 1 diabetes using time to peak glucose or C-peptide during oral glucose tolerance tests (OGTTs) in autoantibody-positive relatives of people with type 1 diabetes.. We examined 2-h OGTTs of participants in the Diabetes Prevention Trial Type 1 (DPT-1) and TrialNet Pathway to Prevention (PTP) studies. We included 706 DPT-1 participants (mean ± SD age, 13.84 ± 9.53 years; BMI Z-score, 0.33 ± 1.07; 56.1% male) and 3,720 PTP participants (age, 16.01 ± 12.33 years; BMI Z-score, 0.66 ± 1.3; 49.7% male). Log-rank testing and Cox regression analyses with adjustments (age, sex, race, BMI Z-score, HOMA-insulin resistance, and peak glucose/C-peptide levels, respectively) were performed.. In two independent at-risk populations, we show that those with delayed OGTT peak times for glucose or C-peptide are at higher risk of diabetes development within 5 years, independent of peak levels. Moreover, time to peak C-peptide appears more predictive than the peak level, suggesting its potential use as a specific biomarker for diabetes progression. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Glucose Tolerance Test; Humans; Male; Young Adult | 2021 |
Gluten-free diet in children with recent-onset type 1 diabetes: A 12-month intervention trial.
To test whether a gluten-free diet (GFD) is associated with the deceleration of the decline in beta-cell capacity in non-coeliac children with recently diagnosed type 1 diabetes.. Forty-five children (aged 10.2 ± 3.3 years) were recruited into a self-selected intervention trial: 26 started with a GFD within a median of 38 days postonset, whereas 19 remained on a standard diet. The main outcomes were the decline in C-peptide area under the curve (AUC) in mixed-meal tolerance tests (MMTTs) at 6 and 12 months relative to 1 month after diabetes onset and the difference in insulin dose, insulin dose-adjusted A1c (IDAA1c) and HbA1c assessed every 3 months. The adherence to the GFD was verified by immunoreactive gluten in the stool and by food questionnaires at every visit. Quality of life (QoL) questionnaires were administered to the participants at the end of the intervention at 12 months. The data were analysed as per protocol (in 39 subjects who duly completed the whole follow-up: 20 in the GFD group, 19 in the control group) by linear and longitudinal regression models adjusted for sex, age and baseline variables.. At 12 months, the difference in C-peptide AUC between subjects in the GFD group and controls was 205 pmol/L (95% CI -223 to 633; P = 0.34) in a model adjusted for age, sex and body weight, and for baseline insulin dose, MMTT C-peptide AUC and HbA1c assessed at 1 month after diagnosis. In a longitudinal analysis of all three time points adjusted for age, sex and body weight, C-peptide declined more slowly in the GFD group than in controls, with the difference in trends being 409 pmol/L/year (P = 0.04). The GFD group had a marginally lower insulin dose (by 0.15 U/kg/day; P = 0.07), a lower IDAA1c (by 1.37; P = 0.01) and a lower mean HbA1c (by 0.7% [7.8 mmol/mol]; P = 0.02) than those of the controls at 12 months. There was no appreciable difference between the groups in daily carbohydrate intake (P = 0.49) or in the QoL reported by the patients (P = 0.70) and their parents/caregivers (P = 0.59).. A GFD maintained over the first year after type 1 diabetes diagnosis was associated with better HbA1c and a prolonged partial remission period. There was a hint of slower C-peptide decline but the association was not strong enough to make definite conclusions. Topics: C-Peptide; Celiac Disease; Child; Diabetes Mellitus, Type 1; Diet, Gluten-Free; Humans; Insulin; Quality of Life | 2020 |
Urinary C-peptide creatinine ratio to differentiate type 2 diabetes mellitus from type 1 in pediatric patients.
Type 2 diabetes mellitus (T2DM) is frequently misdiagnosed in children and treated as type 1 DM (T1DM) with insulin. Urinary C-peptide to creatinine ratio (UCPCR) can be used to measure ß cell function and endogenous insulin. We aimed to assess the value of UCPCR to differentiate T2DM from T1DM in pediatric patients. We assessed UCPCR from urine sample taken 2 h after lunch in 50 children with T1DM and 30 children with T2DM (duration of the disease ≥ 2 years and without renal impairment). Fasting and postprandial C-peptide levels were also evaluated in all included children. Receiver operating characteristic (ROC) curve was performed to assess the optimal UCPCR cutoff level to differentiate T2DM from T1DM in children. UCPCR was significantly lower in children with T1DM compared with those with T2DM (P < 0.001). There was a significant positive correlation between UCPCR and fasting C-peptide, postprandial C-peptide, and age of onset. There was a significant negative correlation between the UCPCR and both HbA1c and duration of DM in T1DM. Fasting C-peptide had a sensitivity of 63%, a specificity of 84% at a cutoff point ≥ 1.3 ng/ml to differentiate T2DM from T1DM. Postprandial C-peptide had a sensitivity of 87%, a specificity of 86% at a cutoff point ≥ 3.2 ng/ml to differentiate T2DM from T1DM. Finally, UCPCR had a sensitivity of 97%, a specificity of 88% at a cutoff point ≥ 0.28 nmol/nmol to differentiate T2DM from T1DM in pediatric patients.Conclusion: UCPCR is an easy noninvasive reliable marker to differentiate T2DM from T1DM in pediatric patients.What is Known:• Type 2 DM (T2DM) is frequently misdiagnosed in children and treated as type 1 DM (T1DM) with insulin.• Urinary C-peptide to creatinine ratio (UCPCR) can be used to measure ß cell function and endogenous insulin.What is New:• We revealed that UCPCR had a sensitivity of 97%, a specificity of 88% at a cutoff point ≥ 0.28 nmol/nmol to differentiate T2DM from T1DM.• UCPCR is an easy noninvasive dependable marker to diagnose T2DM from T1DM in pediatric patients. Topics: Adolescent; Biomarkers; C-Peptide; Case-Control Studies; Child; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Humans; Male; Prospective Studies; ROC Curve; Sensitivity and Specificity | 2020 |
Slowed Metabolic Decline After 1 Year of Oral Insulin Treatment Among Individuals at High Risk for Type 1 Diabetes in the Diabetes Prevention Trial-Type 1 (DPT-1) and TrialNet Oral Insulin Prevention Trials.
We assessed whether oral insulin slowed metabolic decline after 1 year of treatment in individuals at high risk for type 1 diabetes. Two oral insulin trials that did not show efficacy overall and had type 1 diabetes as the primary end point were analyzed: the Diabetes Prevention Trial-Type 1 (DPT-1) and the TrialNet oral insulin trials. Oral glucose tolerance tests at baseline and after 1 year of treatment were analyzed. Among those at high risk (with a Diabetes Prevention Trial-Type 1 Risk Score [DPTRS] ≥6.75), the area under the curve (AUC) C-peptide increased significantly from baseline to 1 year in each oral insulin group, whereas the AUC glucose increased significantly in each placebo group. At 1 year, the AUC C-peptide/AUC glucose (AUC Ratio) was significantly higher in the oral insulin group than in the placebo group in each trial ( Topics: Antibodies, Monoclonal, Humanized; Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Male | 2020 |
Golimumab and Beta-Cell Function in Youth with New-Onset Type 1 Diabetes.
Type 1 diabetes is an autoimmune disease characterized by progressive loss of pancreatic beta cells. Golimumab is a human monoclonal antibody specific for tumor necrosis factor. In this phase 2, multicenter, placebo-controlled, double-blind, parallel-group trial, we randomly assigned, in a 2:1 ratio, children and young adults (age range, 6 to 21 years) with newly diagnosed overt type 1 diabetes to receive subcutaneous golimumab or placebo for 52 weeks. The primary end point was endogenous insulin production, as assessed according to the area under the concentration-time curve for C-peptide level in response to a 4-hour mixed-meal tolerance test (4-hour C-peptide AUC) at week 52. Secondary and additional end points included insulin use, the glycated hemoglobin level, the number of hypoglycemic events, the ratio of fasting proinsulin to C-peptide over time, and response profile.. A total of 84 participants underwent randomization - 56 were assigned to the golimumab group and 28 to the placebo group. The mean (±SD) 4-hour C-peptide AUC at week 52 differed significantly between the golimumab group and the placebo group (0.64±0.42 pmol per milliliter vs. 0.43±0.39 pmol per milliliter, P<0.001). A treat-to-target approach led to good glycemic control in both groups, and there was no significant difference between the groups in glycated hemoglobin level. Insulin use was lower with golimumab than with placebo. A partial-remission response (defined as an insulin dose-adjusted glycated hemoglobin level score [calculated as the glycated hemoglobin level plus 4 times the insulin dose] of ≤9) was observed in 43% of participants in the golimumab group and in 7% of those in the placebo group (difference, 36 percentage points; 95% CI, 22 to 55). The mean number of hypoglycemic events did not differ between the trial groups. Hypoglycemic events that were recorded as adverse events at the discretion of investigators were reported in 13 participants (23%) in the golimumab group and in 2 (7%) of those in the placebo group. Antibodies to golimumab were detected in 30 participants who received the drug; 29 had antibody titers lower than 1:1000, of whom 12 had positive results for neutralizing antibodies.. Among children and young adults with newly diagnosed overt type 1 diabetes, golimumab resulted in better endogenous insulin production and less exogenous insulin use than placebo. (Funded by Janssen Research and Development; T1GER ClinicalTrials.gov number, NCT02846545.). Topics: Adolescent; Antibodies, Monoclonal; Area Under Curve; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Proinsulin; Tumor Necrosis Factor-alpha; Young Adult | 2020 |
Effects of exercise in combination with autologous bone marrow stem cell transplantation for patients with type 1 diabetes.
Stem cell therapy is a promising approach for the treatment of type 1 diabetes mellitus (T1D). Previous studies recommended regular exercise for the control of T1D. Experimental studies showed that a combination of stem cells and exercise yielded a better outcome. Yet, the effect of exercise programs following stem cell transplantation in patients with T1D has not been investigated. Thus, the current study aimed to examine the effect of a combined exercise program on measures of glycemic control in patients with T1D who received autologous bone marrow stem cell transplantation (ABMSCT). Thirty patients with controlled T1D were assigned into two equal groups. Both groups underwent ABMSCT and received insulin therapy and a diabetic diet regime. Only the exercise group followed the combined exercise program. Outcome measures of glycemic control (i.e. fasting blood glucose level [FBG], post-prandial blood glucose level [PPG], HbA1c, daily insulin dosage, and C-peptide levels) were tested before and after a 3-month rehabilitation period. There were significant ( Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Combined Modality Therapy; Diabetes Mellitus, Type 1; Exercise Therapy; Female; Hematopoietic Stem Cell Transplantation; Humans; Insulin; Male; Non-Randomized Controlled Trials as Topic; Young Adult | 2019 |
An improved clinical model to predict stimulated C-peptide in children with recent-onset type 1 diabetes.
Stimulated C-peptide measurement after a mixed meal tolerance test (MMTT) is the accepted gold standard for assessing residual beta-cell function in type 1 diabetes (T1D); however, this approach is impractical outside of clinical trials.. To develop an improved estimate of residual beta-cell function in children with T1D using commonly measured clinical variables.. A clinical model to predict 90-minute MMTT stimulated C-peptide in children with recent-onset T1D was developed from the combined AbATE, START, and TIDAL placebo subjects (n = 46) 6 months post-recruitment using multiple linear regression. This model was then validated in a clinical cohort (Hvidoere study group, n = 262).. A model of estimated C-peptide at 6 months post-diagnosis, which included age, gender, body mass index (BMI), hemoglobin A1c (HbA1c), and insulin dose predicted 90-minute stimulated C-peptide measurements (adjusted R. A clinical model including age, gender, BMI, HbA1c, and insulin dose predicts stimulated C-peptide levels in children with recent-onset T1D. Estimated C-peptide is an improved surrogate to monitor residual beta-cell function outside clinical trial settings. Topics: Adolescent; Adult; Age of Onset; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin Secretion; Insulin-Secreting Cells; Male; Models, Biological; Prognosis; Remission Induction; Treatment Outcome; Young Adult | 2019 |
Mixed-meal tolerance test to assess residual beta-cell secretion: Beyond the area-under-curve of plasma C-peptide concentration.
Residual beta-cell secretion in type 1 diabetes is commonly assessed by area-under-curve of plasma C-peptide concentration (AUC. We analyzed data from 32 youth (age 7 to 17 years) undergoing MMTT within 6 months of type 1 diabetes diagnosis. We related AUC. Postprandial responsiveness M Topics: Adolescent; Area Under Curve; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diagnostic Techniques, Endocrine; Feasibility Studies; Female; Glycated Hemoglobin; Humans; Insulin Secretion; Insulin-Secreting Cells; Male; Meals; Postprandial Period | 2019 |
Residual β cell function and monogenic variants in long-duration type 1 diabetes patients.
BACKGROUNDIn the Joslin Medalist Study (Medalists), we determined whether significant associations exist between β cell function and pathology and clinical characteristics.METHODSIndividuals with type 1 diabetes (T1D) for 50 or more years underwent evaluation including HLA analysis, basal and longitudinal autoantibody (AAb) status, and β cell function by a mixed-meal tolerance test (MMTT) and a hyperglycemia/arginine clamp procedure. Postmortem analysis of pancreases from 68 Medalists was performed. Monogenic diabetes genes were screened for the entire cohort.RESULTSOf the 1019 Medalists, 32.4% retained detectable C-peptide levels (>0.05 ng/mL, median: 0.21 ng/mL). In those who underwent a MMTT (n = 516), 5.8% responded with a doubling of baseline C-peptide levels. Longitudinally (n = 181, median: 4 years), C-peptide levels increased in 12.2% (n = 22) and decreased in 37% (n = 67) of the Medalists. Among those with repeated MMTTs, 5.4% (3 of 56) and 16.1% (9 of 56) had waxing and waning responses, respectively. Thirty Medalists with baseline C-peptide levels of 0.1 ng/mL or higher underwent the clamp procedure, with HLA-/AAb- and HLA+/AAb- Medalists being most responsive. Postmortem examination of pancreases from 68 Medalists showed that all had scattered insulin-positive cells; 59 additionally had few insulin-positive cells within a few islets; and 14 additionally had lobes with multiple islets with numerous insulin-positive cells. Genetic analysis revealed that 280 Medalists (27.5%) had monogenic diabetes variants; in 80 (7.9%) of these Medalists, the variants were classified as "likely pathogenic" (rare exome variant ensemble learner [REVEL] >0.75).CONCLUSIONAll Medalists retained insulin-positive β cells, with many responding to metabolic stimuli even after 50 years of T1D. The Medalists were heterogeneous with respect to β cell function, and many with HLA+ diabetes risk alleles also had monogenic diabetes variants, indicating the importance of genetic testing for clinically diagnosed T1D.FUNDINGFunding for this work was provided by the Dianne Nunnally Hoppes Fund; the Beatson Pledge Fund; the NIH, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); and the American Diabetes Association (ADA). Topics: Adolescent; Aged; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Clamp Technique; HLA-A Antigens; Humans; Insulin-Secreting Cells; Male; Middle Aged; Time Factors | 2019 |
The Role of Laboratory Testing in Differentiating Type 1 Diabetes from Type 2 Diabetes in Patients Undergoing Bariatric Surgery.
It may be difficult to distinguish between adults with type 1 diabetes and type 2 diabetes by clinical assessment. In patients undergoing bariatric surgery, it is critical to correctly classify diabetes subtype to prevent adverse perioperative outcomes including diabetic ketoacidosis. This study aimed to determine whether testing for C-peptide and islet cell antibodies during preoperative evaluation for bariatric surgery could improve the classification of type 1 versus type 2 diabetes compared to clinical assessment alone.. The participant with type 1 diabetes was similar to the 11 participants with type 2 diabetes in age at diagnosis, adiposity, and glycemic control but had the lowest C-peptide levels. Among insulin-treated participants, fasting and stimulated C-peptide correlated strongly with the C-peptide area-under-the-curve on mixed meal tolerance testing (R = 0.86 and 0.88, respectively). Three participants, including the one with type 1 diabetes, were islet cell antibody positive.. Clinical characteristics did not correctly identify type 1 diabetes in this study. Preoperative C-peptide testing may improve diabetes classification in patients undergoing bariatric surgery; further research is needed to define the optimal C-peptide thresholds. Topics: Adult; Autoantibodies; Bariatric Surgery; Blood Glucose; C-Peptide; Clinical Laboratory Techniques; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Fasting; Female; Humans; Male; Middle Aged; Obesity; Postoperative Period; Retrospective Studies; Weight Loss | 2018 |
Glucose-Dependent Insulinotropic Polypeptide (GIP) Inhibits Bone Resorption Independently of Insulin and Glycemia.
The gut hormone glucose-dependent insulinotropic polypeptide (GIP) causes postprandial insulin release and inhibits bone resorption assessed by carboxy-terminal collagen crosslinks (CTX).. To study if GIP affects bone homeostasis biomarkers independently of insulin release and glycemic level.. Randomized, double-blinded, crossover study with 5 study days.. Ten male C-peptide-negative patients with type 1 diabetes.. On 3 matched days with "low glycemia" (plasma glucose in the interval 3 to 7 mmol/L for 120 minutes), we administered intravenous (IV) GIP (4 pmol × kg-1 × min-1), glucagon-like peptide 1 (1 pmol × kg-1 × min-1), or placebo (saline), and on 2 matched days with "high glycemia" (plasma glucose 12 mmol/L for 90 minutes), we administered either GIP or saline.. CTX, procollagen type 1 N-terminal propeptide (P1NP), and parathyroid hormone (PTH).. During low glycemia: GIP progressively suppressed CTX from baseline by up to 59 ± 18% compared with 24 ± 10% during saline infusion (P < 0.0001). Absolute values of P1NP and PTH did not differ between days. During high glycemia: GIP suppressed CTX from baseline by up to 59 ± 19% compared with 7 ± 9% during saline infusion (P < 0.0001). P1NP did not differ between days. GIP suppressed PTH after 60 minutes compared with saline (P < 0.01), but this difference disappeared after 90 minutes.. Short-term GIP infusions robustly reduce bone resorption independently of endogenous insulin secretion and during both elevated and low plasma glucose, but have no effect on P1NP or PTH after 90 minutes. Topics: Adult; Biomarkers; Blood Glucose; Bone Resorption; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Follow-Up Studies; Gastric Inhibitory Polypeptide; Gastrointestinal Agents; Humans; Hyperglycemia; Hypoglycemia; Male; Postprandial Period; Prognosis | 2018 |
The influence of body mass index and age on C-peptide at the diagnosis of type 1 diabetes in children who participated in the diabetes prevention trial-type 1.
The extent of influence of BMI and age on C-peptide at the diagnosis of type 1 diabetes (T1D) is unknown. We thus studied the impact of body mass index Z-scores (BMIZ) and age on C-peptide measures at and soon after the diagnosis of T1D.. Data from Diabetes Prevention Trial-Type 1 (DPT-1) participants <18.0 years at diagnosis was analyzed. Analyses examined associations of C-peptide measures with BMIZ and age in 2 cohorts: oral glucose tolerance tests (OGTTs) at diagnosis (n = 99) and mixed meal tolerance tests (MMTTs) <6 months after diagnosis (n = 80). Multivariable linear regression was utilized.. Fasting and area under the curve (AUC) C-peptide from OGTTs (n = 99) at diagnosis and MMTTs (n = 80) after diagnosis were positively associated with BMIZ and age (P < .001 for all). Associations persisted when BMIZ and age were included as independent variables in regression models (P < .001 for all). BMIZ and age explained 31%-47% of the variance of C-peptide measures. In an example, 2 individuals with identical AUC C-peptide values had an approximate 5-fold difference in values after adjustments for BMIZ and age. The association between fasting glucose and C-peptide decreased markedly when fasting C-peptide values were adjusted (r = 0.30, P < .01 to r = 0.07, n.s.).. C-peptide measures are strongly and independently related to BMIZ and age at and soon after the diagnosis of T1D. Adjustments for BMIZ and age cause substantial changes in C-peptide values, and impact the association between glycemia and C-peptide. Such adjustments can improve assessments of β-cell impairment at diagnosis. Topics: Adolescent; Age Factors; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Male | 2018 |
Alpha-1 antitrypsin treatment of new-onset type 1 diabetes: An open-label, phase I clinical trial (RETAIN) to assess safety and pharmacokinetics.
To determine the safety and pharmacokinetics of alpha-1 antitrypsin (AAT) in adults and children.. Short-term AAT treatment restores euglycemia in the non-obese mouse model of type 1 diabetes. A phase I multicenter study in 16 subjects with new-onset type 1 diabetes studied the safety and pharmacokinetics of Aralast NP (AAT). This open-label, dose-escalation study enrolled 8 adults aged 16 to 35 years and 8 children aged 8 to 15 years within 100 days of diagnosis, to receive 12 infusions of AAT: a low dose of 45 mg/kg weekly for 6 weeks, followed by a higher dose of 90 mg/kg for 6 weeks.. C-peptide secretion during a mixed meal, hemoglobin A1c (HbA1c), and insulin usage remained relatively stable during the treatment period. At 72 hours after infusion of 90 mg/kg, mean levels of AAT fell below 2.0 g/L for 7 of 15 subjects. To identify a plasma level of AAT likely to be therapeutic, pharmacodynamic ex vivo assays were performed on fresh whole blood from adult subjects. Polymerase chain reaction (PCR) analyses were performed on inhibitor of IKBKE, NOD1, TLR1, and TRAD gene expression, which are important for activation of nuclear factor-κB (NF-κB) and apoptosis pathways. AAT suppressed expression dose-dependently; 50% inhibition was achieved in the 2.5 to 5.0 mg/mL range.. AAT was well tolerated and safe in subjects with new-onset type 1 diabetes. Weekly doses of AAT greater than 90 mg/kg may be necessary for an optimal therapeutic effect. Topics: Adolescent; Adult; alpha 1-Antitrypsin; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infusions, Intravenous; Male; Young Adult | 2018 |
Effect of simultaneous vaccination with H1N1 and GAD-alum on GAD
A European Phase III trial of GAD formulated with aluminium hydroxide (GAD-alum) failed to reach its primary endpoint (preservation of stimulated C-peptide secretion from baseline to 15 months in type 1 diabetes patients), but subgroup analysis showed a clinical effect when participants from Nordic countries were excluded, raising concern as to whether the mass vaccination of the Swedish and Finnish populations with the Pandemrix influenza vaccine could have influenced the study outcomes. In the current study, we aimed to assess whether Pandemrix vaccination affects the specific immune responses induced by GAD-alum and the C-peptide response.. In this secondary analysis, we analysed data acquired from the Swedish participants in the Phase III GAD-alum trial who received subcutaneous GAD-alum vaccination (two doses, n = 43; four doses, n = 46) or placebo (n = 48). GAD autoantibodies (GADA) and H1N1 autoantibodies, GAD. GADA levels at 15 months were associated with the relative time between GAD-alum and Pandemrix administration in participants who received two doses of the GAD-alum vaccine (p = 0.015, r = 0.4). Both in participants treated with two doses and four doses of GAD-alum, GADA levels were higher when the relative time between vaccines was ≥210 days (p < 0.05). In the group that received two doses of GAD-alum, levels of several GAD. In individuals who received two doses of GAD-alum, receiving the Pandemrix vaccine closer to the first GAD-alum injection, i.e. <150 days, seemed to affect both GAD. ClinicalTrials.gov NCT00723411. Topics: Adolescent; Alum Compounds; Autoantibodies; C-Peptide; Child; Cytokines; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Finland; Glutamate Decarboxylase; Hemagglutinins; Humans; Immune System; Influenza A Virus, H1N1 Subtype; Influenza Vaccines; Influenza, Human; Insulin; Insulin Secretion; Male; Normal Distribution; Sweden; Time Factors; Vaccination; Young Adult | 2017 |
Effect of eicosapentaenoic acid and docosahexaenoic acid supplementation on C-peptide preservation in pregnant women with type-1 diabetes: randomized placebo controlled clinical trial.
Type-1 diabetes mellitus (T1DM) is caused by autoimmune insulitis. There are evidences that pregnancy and n-3 fatty acids exhibit suppressive effect on human inflammatory system.. Ninety pregnant women with T1DM were included in the prospective randomized placebo controlled clinical trial. Forty-seven of them were put on standard diabetic diet enriched with EPA and DHA twice a day (EPA 120 mg and DHA 616 mg; Study group) and 43 pregnant diabetic women were on standard diabetic diet with placebo (Control group). Duration of T1DM in all participants was between 5 to 30 years. Blood samples were analyzed from all pregnant women for fasting C-peptide (FC-peptide), fasting plasma glucose (FPG) and HbA1c in each trimester throughout pregnancy and after delivery. Umbilical vein blood was analyzed for fetal C-peptide level, glucose concentration and insulin resistance.. In the Study group FC-peptide concentration raised from 59.6±103.9 pmol/l in first trimester, to 67.7±101.3 pmol/l in the second trimester and to 95.1±152.7 pmol/l in the third trimester. Comparing the FC-peptide values during first and third trimester a statistically significant increase in third trimester was found (P<0.001). In the Control group FC-peptide concentration ranged from 41.7±91.6 pmol/l in the first trimester to 41.2±70.9 mmol/l in the second trimester while in the third trimester it reached 52.4±95.3 pmol/l. Comparing the FC-peptide values during first and third trimester the statistical difference was not significant.. Combining of LC n-3 PUFAs and pregnancy yields immunological tolerance and stimulates the production of endogenous insulin in women with T1DM. Topics: Adult; Biomarkers; C-Peptide; Combined Modality Therapy; Diabetes Mellitus, Type 1; Diet, Diabetic; Dietary Supplements; Docosahexaenoic Acids; Eicosapentaenoic Acid; Female; Fetal Blood; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Resistance; Maternal Nutritional Physiological Phenomena; Pregnancy; Pregnancy in Diabetics; Young Adult | 2017 |
Metabolic and immune effects of immunotherapy with proinsulin peptide in human new-onset type 1 diabetes.
Topics: Adolescent; Adult; Autoantibodies; Autoantigens; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Humans; Immunophenotyping; Immunotherapy; Male; Middle Aged; Peptides; Proinsulin; T-Lymphocytes, Regulatory; Young Adult | 2017 |
Remodeling T cell compartments during anti-CD3 immunotherapy of type 1 diabetes.
The immunological mechanism(s) of action whereby teplizumab preserves C-peptide levels in the progression of patients with recent onset type 1 diabetes (T1D) is still not well understood. In the present study, we evaluated the kinetics of T cell modulation in peripheral blood following two 14-day courses of teplizumab therapy one year apart in recent onset T1D participants in the AbATE clinical trial. Transient rises in PD-1+Foxp3+ Treg and potentially anergic (CD57-KLRG1-PD-1+) cells in the circulating CD4 T cell compartment were paralleled by more profound increases in circulating CD8 T cells with traits of exhaustion (CD57-KLRG1+PD-1+, TIGIT+KLRG1+, and persistent down-modulation of CD127). The observed phenotypic changes across cell types were associated with favorable response to treatment in the subgroup of study participants that did not develop anti-drug antibodies after the first course of therapy. These findings provide new insights on the duration and complexity of T cell modulation with teplizumab therapy in recent onset T1D, and in addition, suggest that coordinated immune mechanisms of tolerance that favor CD4 Treg function and restrain CD4 non-Treg and CD8 T cell activation may contribute to treatment success. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; CD3 Complex; CD57 Antigens; CD8-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; Forkhead Transcription Factors; Gene Expression; Humans; Hypoglycemic Agents; Immune Tolerance; Immunomodulation; Immunotherapy; Interleukin-7 Receptor alpha Subunit; Lectins, C-Type; Male; Programmed Cell Death 1 Receptor; Receptors, Immunologic; T-Lymphocytes, Regulatory; Trans-Activators | 2017 |
Effects of
Recent evidence has demonstrated that, among other factors, dysbiosis (imbalances in the composition and function of the gut microbiota) may be relevant in the development of type 1 diabetes (T1D). Thus, gut microbiota may be a target for improving outcomes in subjects with T1D. The aim of the study is to examine the effects of. A total of 96 children aged 8 to 17 years with newly diagnosed T1D, confirmed by clinical history and the presence of at least one positive autoantibody, will be enrolled in a double-blind, randomised, placebo-controlled trial in which they will receive. The Bioethics Committee approved the study protocol. The findings of this trial will be submitted to a peer-reviewed paediatric journal. Abstracts will be submitted to relevant national and international conferences.. NCT03032354; Pre-results. Topics: Adolescent; Area Under Curve; Bifidobacterium animalis; C-Peptide; Child; Clinical Protocols; Diabetes Mellitus, Type 1; Double-Blind Method; Dysbiosis; Enzyme-Linked Immunosorbent Assay; Female; Gastrointestinal Microbiome; Humans; Insulin-Secreting Cells; Lacticaseibacillus rhamnosus; Male; Probiotics | 2017 |
Influence of initial insulin dosage on blood glucose dynamics of children and adolescents with newly diagnosed type 1 diabetes mellitus.
To investigate the effect of initial insulin dosage on blood glucose (BG) dynamics, β-cell protection, and oxidative stress in type 1 diabetes mellitus.. Sixty newly diagnosed type 1 diabetes mellitus patients were randomly assigned to continuous subcutaneous insulin infusions of 0.6 ± 0.2 IU/kg/d (group 1), 1.0 ± 0.2 IU/kg/d (group 2), or 1.4 ± 0.2 IU/kg/d (group 3) for 3 wk. BG was monitored continuously for the first 10 d and the last 2 d of wk 2 and 3. A total of 24-hour urinary 8-iso-PGF2α was assayed on days 8, 9, and 10. The occurrence and duration of the honeymoon period were recorded. Fasting C-peptide and glycosylated hemoglobin (HbA1c) were assayed after 1, 6, and 12 months of insulin treatment.. BG decreased to the target range by the end of wk 3 (group 1), wk 2 (group 2), or wk 1 (group 3). The actual insulin dosage over the 3 wk, frequency of hypoglycemia on wk 1 and 2, and median BG at the end of wk 1 differed significantly, but not 8-iso-PGF2α and the honeymoon period in the three groups. No severe hypoglycemia event was observed in any patient, but there was significant difference in the first occurrence of hypoglycemia.. Differences in initial insulin dosage produced different BG dynamics in wk 1, equivalent BG dynamics on wk 2 and 3, but had no influence on short- and long-term BG control and honeymoon phase. The wide range of initial insulin dosage could be chosen if guided by BG monitoring. Topics: Biomarkers; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Dinoprost; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Infusion Systems; Insulin Secretion; Insulin-Secreting Cells; Male; Monitoring, Ambulatory; Oxidative Stress | 2017 |
Changes in beta cell function during the proximate post-diagnosis period in persons with type 1 diabetes.
Prior studies examining beta-cell preservation in type 1 diabetes have predominantly assessed stimulated C-peptide concentrations approximately 10 wk after diagnosis. We examined whether earlier assessments might aid in prediction of beta cell function over time.. Using data from a multi-center randomized trial assessing the effect of intensive diabetes management initiated within 1 wk of diagnosis, we assessed which clinical factors predicted 90-min mixed-meal tolerance test (MMTT) stimulated C-peptide values obtained 2 and 6 wk after diagnosis. We also studied associations of these factors with C-peptide values at 1- and 2-year post-diagnosis. Data from intervention and control groups were pooled.. Among 67 study participants (mean age 13.3 ± 5.7 yr, range 7.8-45.7 yr) in multivariable analyses, C-peptide increased from baseline to 2 wks and then 6 wk. C-peptide levels at these times were significantly correlated with 1- and 2-yr C-peptide concentrations (all p < 0.001), with the strongest observed associations between 6-wk C-peptide and the 1- and 2-yr values (r = 0.66 and r = 0.61, respectively). In multivariable analyses, greater baseline and 6-wk C-peptide, and older age independently predicted greater 1- and 2-yr C-peptide concentrations.. C-peptide assessments close to diagnosis were predictive of subsequent C-peptide production. Our data demonstrate a clear increase in C-peptide over the initial 6 wk after diabetes diagnosis followed by a plateau. Our data do not suggest that MMTT assessments performed closer to diagnosis than 6 wk would improve prediction of subsequent residual beta cell function. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells; Middle Aged; Young Adult | 2016 |
Mobilization without immune depletion fails to restore immunological tolerance or preserve beta cell function in recent onset type 1 diabetes.
Granulocyte colony-stimulating factor (G-CSF) has been used to restore immune competence following chemoablative cancer therapy and to promote immunological tolerance in certain settings of autoimmunity. Therefore, we tested the potential of G-CSF to impact type 1 diabetes (T1D) progression in patients with recent-onset disease [n = 14; n = 7 (placebo)] and assessed safety, efficacy and mechanistic effects on the immune system. We hypothesized that pegylated G-CSF (6 mg administered subcutaneously every 2 weeks for 12 weeks) would promote regulatory T cell (Treg) mobilization to a degree capable of restoring immunological tolerance, thus preventing further decline in C-peptide production. Although treatment was well tolerated, G-CSF monotherapy did not affect C-peptide production, glycated haemoglobin (HbA1c) or insulin dose. Mechanistically, G-CSF treatment increased circulating neutrophils during the 12-week course of therapy (P < 0·01) but did not alter Treg frequencies. No effects were observed for CD4(+) : CD8(+) T cell ratio or the ratio of naive : memory (CD45RA(+)/CD45RO(+)) CD4(+) T cells. As expected, manageable bone pain was common in subjects receiving G-CSF, but notably, no severe adverse events such as splenomegaly occurred. This study supports the continued exploration of G-CSF and other mobilizing agents in subjects with T1D, but only when combined with immunodepleting agents where synergistic mechanisms of action have previously demonstrated efficacy towards the preservation of C-peptide. Topics: Adolescent; Adult; C-Peptide; CD4-CD8 Ratio; Child; Diabetes Mellitus, Type 1; Disease Progression; Drug Administration Schedule; Female; Glycated Hemoglobin; Granulocyte Colony-Stimulating Factor; Humans; Immune Tolerance; Insulin; Insulin-Secreting Cells; Leukocyte Count; Lymphocyte Depletion; Male; Middle Aged; Neutrophils; Polyethylene Glycols; Recombinant Proteins; Splenomegaly; T-Lymphocytes, Regulatory; Young Adult | 2016 |
Glucose homeostasis after simultaneous pancreas and kidney transplantation: a comparison of subjects with C-peptide-positive non-type 1 diabetes mellitus and type 1 diabetes mellitus.
While simultaneous pancreas kidney transplant (SPKTx) is a therapeutic option for patients with type 1 diabetes (T1DM) and renal failure, few centers offer SPKTx to "select" non-T1DM patients. To address concerns that existing insulin resistance may limit the benefits of the pancreas allograft among non-T1DM, we compared several indices of glucose homeostasis, in "select" non-T1DM and T1DM patients who received SPKTx.. Criteria for "select" non-T1DM included the following: positive C-peptide, BMI <30 kg/m(2) , treatment with oral agents before insulin initiation, and insulin at <1 unit/kg/d. We compared several indices of glucose homeostasis within 1 yr post-SPKTx among seven "select" patients with non-T1DM and nine patients with T1DM with similar age, BMI, and immunosuppression. Measurements of insulin resistance included the following: homeostatic model, insulin sensitivity index, and insulin-glucose ratio; insulin secretion measures included the following: corrected insulin response.. Non-T1DM had similar pre-transplant metabolic (fasting glucose, HbA1c, blood pressure, and lipid) parameters to the T1DM cohort. There were no significant differences in the various measures of insulin resistance and secretion between T1DM and "select" non-T1DM patients.. Our results suggest SPKTx should be considered in the therapeutic armamentarium among carefully select non-T1DM with features of minimal insulin resistance; however, a larger cohort with longer follow-up is needed to confirm our results. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Homeostasis; Humans; Insulin Resistance; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Prognosis; Prospective Studies; Risk Factors; Young Adult | 2016 |
Umbilical Cord Mesenchymal Stromal Cell With Autologous Bone Marrow Cell Transplantation in Established Type 1 Diabetes: A Pilot Randomized Controlled Open-Label Clinical Study to Assess Safety and Impact on Insulin Secretion.
To determine the safety and effects on insulin secretion of umbilical cord (UC) mesenchymal stromal cells (MSCs) plus autologous bone marrow mononuclear cell (aBM-MNC) stem cell transplantation (SCT) without immunotherapy in established type 1 diabetes (T1D).. Between January 2009 and December 2010, 42 patients with T1D were randomized (n = 21/group) to either SCT (1.1 × 10(6)/kg UC-MSC, 106.8 × 10(6)/kg aBM-MNC through supraselective pancreatic artery cannulation) or standard care (control). Patients were followed for 1 year at 3-month intervals. The primary end point was C-peptide area under the curve (AUC(C-Pep)) during an oral glucose tolerance test at 1 year. Additional end points were safety and tolerability of the procedure, metabolic control, and quality of life.. The treatment was well tolerated. At 1 year, metabolic measures improved in treated patients: AUCC-Pep increased 105.7% (6.6 ± 6.1 to 13.6 ± 8.1 pmol/mL/180 min, P = 0.00012) in 20 of 21 responders, whereas it decreased 7.7% in control subjects (8.4 ± 6.8 to 7.7 ± 4.5 pmol/mL/180 min, P = 0.013 vs. SCT); insulin area under the curve increased 49.3% (1,477.8 ± 1,012.8 to 2,205.5 ± 1,194.0 mmol/mL/180 min, P = 0.01), whereas it decreased 5.7% in control subjects (1,517.7 ± 630.2 to 1,431.7 ± 441.6 mmol/mL/180 min, P = 0.027 vs. SCT). HbA1c decreased 12.6% (8.6 ± 0.81% [70.0 ± 7.1 mmol/mol] to 7.5 ± 1.0% [58.0 ± 8.6 mmol/mol], P < 0.01) in the treated group, whereas it increased 1.2% in the control group (8.7 ± 0.9% [72.0 ± 7.5 mmol/mol] to 8.8 ± 0.9% [73 ± 7.5 mmol/mol], P < 0.01 vs. SCT). Fasting glycemia decreased 24.4% (200.0 ± 51.1 to 151.2 ± 22.1 mg/dL, P < 0.002) and 4.3% in control subjects (192.4 ± 35.3 to 184.2 ± 34.3 mg/dL, P < 0.042). Daily insulin requirements decreased 29.2% in only the treated group (0.9 ± 0.2 to 0.6 ± 0.2 IU/day/kg, P = 0.001), with no change found in control subjects (0.9 ± 0.2 to 0.9 ± 0.2 IU/day/kg, P < 0.01 vs. SCT).. Transplantation of UC-MSC and aBM-MNC was safe and associated with moderate improvement of metabolic measures in patients with established T1D. Topics: Adolescent; Adult; Bone Marrow Transplantation; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Male; Mesenchymal Stem Cell Transplantation; Pilot Projects; Quality of Life; Transplantation, Autologous; Umbilical Cord; Young Adult | 2016 |
Effects of subcutaneous, low-dose glucagon on insulin-induced mild hypoglycaemia in patients with insulin pump treated type 1 diabetes.
To investigate the dose-response relationship of subcutaneous (s.c.) glucagon administration on plasma glucose and on counter-regulatory hormone responses during s.c. insulin-induced mild hypoglycaemia in patients with type 1 diabetes treated with insulin pumps.. Eight insulin pump-treated patients completed a blinded, randomized, placebo-controlled study. Hypoglycaemia was induced in the fasting state by an s.c. insulin bolus and, when plasma glucose reached 3.4 mmol/l [95% confidence interval (CI) 3.2-3.5], an s.c. bolus of either 100, 200, 300 µg glucagon or saline was administered. Plasma glucose, counter-regulatory hormones, haemodynamic variables and side effects were measured throughout each study day. Peak plasma glucose level was the primary endpoint.. Plasma glucose level increased significantly by a mean (95% CI) of 2.3 (1.7-3.0), 4.2 (3.5-4.8) and 5.0 (4.3-5.6) mmol/l to 6.1 (4.9-7.4), 7.9 (6.4-9.3) and 8.7 (7.8-9.5) vs 3.6 (3.4-3.9) mmol/l (p < 0.001) after the three different glucagon doses as compared with saline, and the increase was neither correlated with weight nor insulin levels. Area under the plasma glucose curve, peak plasma glucose, time to peak plasma glucose and duration of plasma glucose level above baseline were significantly enhanced with increasing glucagon doses; however, these were not significantly different between 200 and 300 µg glucagon. Free fatty acids and heart rates were significantly lower initially after glucagon than after saline injection. Other haemodynamic variables, counter-regulatory hormones and side effects did not differ between interventions.. An s.c. low-dose glucagon bolus effectively restores plasma glucose after insulin overdosing. Further research is needed to investigate whether low-dose glucagon may be an alternative treatment to oral carbohydrate intake for mild hypoglycaemia in patients with type 1 diabetes. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Glucagon; Humans; Hypoglycemia; Hypoglycemic Agents; Injections, Subcutaneous; Insulin Antagonists; Insulin Aspart; Insulin Infusion Systems; Male; Middle Aged; Severity of Illness Index; Single-Blind Method; Young Adult | 2016 |
Fasting C-peptide and Related Parameters Characterizing Insulin Secretory Capacity for Correctly Classifying Diabetes Type and for Predicting Insulin Requirement in Patients with Type 2 Diabetes.
C-peptide allows estimation of insulin secretion even in the presence of insulin treatment. C-peptide may be suitable for the differential diagnosis of type 1 and type 2 diabetes, and, within type 2 diabetes, of insulin-requiring vs. non-insulin-requiring patients. Relating C-peptide concentrations to ambient glucose levels might improve its diagnostic potential.. The diagnostic value (a) fasting C-peptide, (b) C-peptide/glucose ratios, and (c) the HOMA-ßC-peptide-index for predicting a diagnosis of type 1 (vs. type 2) diabetes were assessed.. Specialised hospital for the care of diabetic patients (inpatient treatment). 303 patients with type 1 diabetes and 841 patients with type 2 diabetes.. Odds ratios and 95% confidence intervals for a clinical diagnosis of type 1 diabetes or for insulin treatment by deciles of (a) fasting C-peptide, (b) C-peptide/glucose ratios, and (c) HOMA-ßC-peptide-index.. Low C-peptide concentrations were associated with a high odds ratio for type 1 diabetes and vice versa (p<0.0001). Concentrations of 0.13-0.36 nmol/l did not discriminate. C-peptide/glucose ratios or HOMA-ßC-Peptide did not perform better. The ability of all 3 parameters to predict the necessity for insulin treatment within the population of type 2-diabetic patients was low.. Fasting C-peptide and derived parameters help to differentiate type 1 from type 2 diabetes, but there is a range of C-peptide concentrations that does not help discriminate. Relating C-peptide to glucose did not improve diagnostic accuracy. C-peptide does not help predicting a need for insulin treatment in patients with type 2 diabetes. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Humans; Male; Middle Aged | 2016 |
Urinary C-peptide analysis in an intervention study: experience from the DEFEND-2 otelixizumab trial.
To demonstrate that analysis of urinary C-peptide across multiple study sites in the context of an intervention trial (DEFEND-2) is a viable alternative to mixed meal testing and delivers results that correlate to mixed meal testing estimation of endogenous insulin production.. Second morning void urine was collected for analysis and was available from 161 subjects at baseline (55 placebo, 106 otelixizumab), and 146 subjects (47 placebo, 99 otelixizumab) at month 12. Urinary C-peptide concentration was corrected for urinary creatinine [urinary C-peptide/creatinine ratio (UCPCR)] and serum C-peptide from the mixed meal tolerance test was calculated using area under the plasma concentration-time curve (AUC) normalized over 120 min. The correlation between mixed meal stimulated C-peptide AUC (mmol/l/min) and UCPCR (nmol/mmol), as well as the correlation between insulin use (IU/kg), and HbA. UCPCR and mixed meal testing C-peptide AUC were correlated, with a correlation coefficient of 0.4172. UCPCR was not correlated with exogenous insulin use (r = -0.089) or with HbA. Urinary C-peptide estimation should be considered as a measure of endogenous insulin production in future Type 1 diabetes mellitus outcome trials. A change in the timing for urine collection (to 120 min post standard meal) may provide a tighter correlation to C-peptide measured via a traditional mixed meal test. Topics: Adolescent; Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Longitudinal Studies; Male; Meals; Placebos; Postprandial Period; Urinalysis | 2016 |
Long-Acting C-Peptide and Neuropathy in Type 1 Diabetes: A 12-Month Clinical Trial.
Lack of C-peptide in type 1 diabetes may be an important contributing factor in the development of microvascular complications. Replacement of native C-peptide has been shown to exert a beneficial influence on peripheral nerve function in type 1 diabetes. The aim of this study was to evaluate the efficacy and safety of a long-acting C-peptide in subjects with type 1 diabetes and mild to moderate peripheral neuropathy.. A total of 250 patients with type 1 diabetes and peripheral neuropathy received long-acting (pegylated) C-peptide in weekly dosages of 0.8 mg (n = 71) or 2.4 mg (n = 73) or placebo (n = 106) for 52 weeks. Bilateral sural nerve conduction velocity (SNCV) and vibration perception threshold (VPT) on the great toe were measured on two occasions at baseline, at 26 weeks, and at 52 weeks. The modified Toronto Clinical Neuropathy Score (mTCNS) was used to grade the peripheral neuropathy.. Plasma C-peptide rose during the study to 1.8-2.2 nmol/L (low dose) and to 5.6-6.8 nmol/L (high dose). After 52 weeks, SNCV had increased by 1.0 ± 0.24 m/s (P < 0.001 within group) in patients receiving C-peptide (combined groups), but the corresponding value for the placebo group was 1.2 ± 0.29 m/s. Compared with basal, VPT had improved by 25% after 52 weeks of C-peptide therapy (Δ for combined C-peptide groups: -4.5 ± 1.0 μm, placebo group: -0.1 ± 0.9 μm; P < 0.001). mTCNS was unchanged during the study.. Once-weekly subcutaneous administration of long-acting C-peptide for 52 weeks did not improve SNCV, other electrophysiological variables, or mTCNS but resulted in marked improvement of VPT compared with placebo. Topics: Adolescent; Adult; Aged; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Dose-Response Relationship, Drug; Double-Blind Method; Female; Follow-Up Studies; Humans; Male; Middle Aged; Peripheral Nerves; Regression Analysis; Young Adult | 2016 |
Factors Associated with Higher Pro-Inflammatory Tumor Necrosis Factor-α Levels in Young Women with Type 1 Diabetes.
While cytokines play a role in the etiology of type 1 diabetes, cytokines later in the disease are less understood. We therefore investigated associations of pro-inflammatory tumor necrosis factor-α levels measured at prolonged disease duration with C-peptide at diagnosis, long-term glycemic control, diabetes duration, clinical factors, and health behaviors.. Data and blood were collected during an ancillary study to the longitudinal Wisconsin Diabetes Registry, a population-based cohort followed since diagnosis of type 1 diabetes. The ancillary study was conducted at 13-18 years diabetes duration, and enrolled premenopausal women age 18-45 years (n=87).. Higher tumor necrosis factor-α levels at 13-18 years diabetes duration were independently associated with longer duration (p=0.0004) and worse current renal function (p=0.02). Additionally, diabetes duration modified both of the positive associations of tumor necrosis factor-α levels (both interactions p≤0.01) with mean glycemic control during the previous 10 years (significant only in women with longer durations) and current daily caffeine intake (significant only in women with shorter durations). In women with C-peptide measured at diagnosis (n=50), higher tumor necrosis factor-α levels at 13-18 years duration were associated with lower C-peptide (p=0.01), independent of glycemic control during the previous 10 years.. Lower residual C-peptide at diagnosis and poor long-term glycemic control independently predicted higher pro-inflammatory tumor necrosis factor-α levels years later. The novel relationship with C-peptide needs confirmation in a larger cohort. Given the association between tumor necrosis factor-α and diabetes complications, further longitudinal studies may help clarify the potentially complex associations between glycemic control, inflammatory cytokines, and complications. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Middle Aged; Registries; Time Factors; Tumor Necrosis Factor-alpha | 2016 |
Antithymocyte globulin therapy for patients with recent-onset type 1 diabetes: 2 year results of a randomised trial.
Type 1 diabetes results from T cell mediated destruction of beta cells. We conducted a trial of antithymocyte globulin (ATG) in new-onset type 1 diabetes (the Study of Thymoglobulin to ARrest T1D [START] trial). Our goal was to evaluate the longer-term safety and efficacy of ATG in preserving islet function at 2 years.. A multicentre, randomised, double-blind, placebo-controlled trial of 6.5 mg/kg ATG (Thymoglobulin) vs placebo in patients with new-onset type 1 diabetes was conducted at seven university medical centres and one Children's Hospital in the USA. The site-stratified randomisation scheme was computer generated at the data coordinating centre using permuted-blocks of size 3 or 6. Eligible participants were between the ages of 12 and 35, and enrolled within 100 days from diagnosis. Subjects were randomised to 6.5 mg/kg ATG (thymoglobulin) vs placebo in a 2:1 ratio. Participants were blinded, and the study design included two sequential patient-care teams: an unblinded study-drug administration team (for the first 8 weeks), and a blinded diabetes management team (for the remainder of the study). Endpoints assessed at 24 months included meal-stimulated C-peptide AUC, safety and immunological responses.. Fifty-eight patients were enrolled; at 2 years, 35 assigned to ATG and 16 to placebo completed the study. The pre-specified endpoints were not met. In post hoc analyses, older patients (age 22-35 years) in the ATG group had significantly greater C-peptide AUCs at 24 months than placebo patients. Using complete preservation of baseline C-peptide at 24 months as threshold, nine of 35 ATG-treated participants (vs 2/16 placebo participants) were classified as responders; nine of 11 responders (67%) were older. All participants reported at least one adverse event (AE), with 1,148 events in the 38 ATG participants vs 415 in the 20 placebo participants; a comparable number of infections were noted in the ATG and placebo groups, with no opportunistic infections nor difficulty clearing infections in either group. Circulating T cell subsets depleted by ATG partially reconstituted, but regulatory, naive and central memory subsets remained significantly depleted at 24 months. Beta cell autoantibodies did not change over the 24 months in the ATG-treated or placebo participants. At 12 months, ATG-treated participants had similar humoral immune responses to tetanus and HepA vaccines as placebo-treated participants, and no increased infections.. A brief course of ATG substantially depleted T cell subsets, including regulatory cells, but did not preserve islet function 24 months later in the majority of patients with new-onset type 1 diabetes. ATG preserved C-peptide secretion in older participants, which may warrant further study.. ClinicalTrials.gov NCT00515099 PUBLIC DATA REPOSITORY: START datasets are available in TrialShare www.itntrialshare.org. National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH). The trial was conducted by the Immune Tolerance Network (ITN). Topics: Adolescent; Adult; Antilymphocyte Serum; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Humans; Hypoglycemic Agents; Immunity, Humoral; Randomized Controlled Trials as Topic; T-Lymphocyte Subsets; Treatment Outcome; Young Adult | 2016 |
Random non-fasting C-peptide: bringing robust assessment of endogenous insulin secretion to the clinic.
Measuring endogenous insulin secretion using C-peptide can assist diabetes management, but standard stimulation tests are impractical for clinical use. Random non-fasting C-peptide assessment would allow testing when a patient is seen in clinic.. We compared C-peptide at 90 min in the mixed meal tolerance test (sCP) with random non-fasting blood C-peptide (rCP) and random non-fasting urine C-peptide creatinine ratio (rUCPCR) in 41 participants with insulin-treated diabetes [median age 72 (interquartile range 68-78); diabetes duration 21 (14-31) years]. We assessed sensitivity and specificity for previously reported optimal mixed meal test thresholds for severe insulin deficiency (sCP < 200 pmol//l) and Type 1 diabetes/inability to withdraw insulin (< 600 pmol//l), and assessed the impact of concurrent glucose.. rCP and sCP levels were similar (median 546 and 487 pmol//l, P = 0.92). rCP was highly correlated with sCP, r = 0.91, P < 0.0001, improving to r = 0.96 when excluding samples with concurrent glucose < 8 mmol//l. An rCP cut-off of 200 pmol//l gave 100% sensitivity and 93% specificity for detecting severe insulin deficiency, with area under the receiver operating characteristic curve of 0.99. rCP < 600 pmol//l gave 87% sensitivity and 83% specificity to detect sCP < 600 pmol//l. Specificity improved to 100% when excluding samples with concurrent glucose < 8 mmol//l. rUCPCR (0.52 nmol/mmol) was also well-correlated with sCP, r = 0.82, P < 0.0001. A rUCPCR cut-off of < 0.2 nmol/ mmol gave sensitivity and specificity of 83% and 93% to detect severe insulin deficiency, with area under the receiver operating characteristic curve of 0.98.. Random non-fasting C-peptide measures are strongly correlated with mixed meal C-peptide, and have high sensitivity and specificity for identifying clinically relevant thresholds. These tests allow assessment of C-peptide at the point patients are seen for clinical care. Topics: Aged; C-Peptide; Clinical Laboratory Techniques; Diabetes Mellitus, Type 1; Diagnostic Techniques, Endocrine; Fasting; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Male; Meals | 2016 |
Phase 3 Trial of Transplantation of Human Islets in Type 1 Diabetes Complicated by Severe Hypoglycemia.
Impaired awareness of hypoglycemia (IAH) and severe hypoglycemic events (SHEs) cause substantial morbidity and mortality in patients with type 1 diabetes (T1D). Current therapies are effective in preventing SHEs in 50-80% of patients with IAH and SHEs, leaving a substantial number of patients at risk. We evaluated the effectiveness and safety of a standardized human pancreatic islet product in subjects in whom IAH and SHEs persisted despite medical treatment.. This multicenter, single-arm, phase 3 study of the investigational product purified human pancreatic islets (PHPI) was conducted at eight centers in North America. Forty-eight adults with T1D for >5 years, absent stimulated C-peptide, and documented IAH and SHEs despite expert care were enrolled. Each received immunosuppression and one or more transplants of PHPI, manufactured on-site under good manufacturing practice conditions using a common batch record and standardized lot release criteria and test methods. The primary end point was the achievement of HbA1c <7.0% (53 mmol/mol) at day 365 and freedom from SHEs from day 28 to day 365 after the first transplant.. The primary end point was successfully met by 87.5% of subjects at 1 year and by 71% at 2 years. The median HbA1c level was 5.6% (38 mmol/mol) at both 1 and 2 years. Hypoglycemia awareness was restored, with highly significant improvements in Clarke and HYPO scores (P > 0.0001). No study-related deaths or disabilities occurred. Five of the enrollees (10.4%) experienced bleeds requiring transfusions (corresponding to 5 of 75 procedures), and two enrollees (4.1%) had infections attributed to immunosuppression. Glomerular filtration rate decreased significantly on immunosuppression, and donor-specific antibodies developed in two patients.. Transplanted PHPI provided glycemic control, restoration of hypoglycemia awareness, and protection from SHEs in subjects with intractable IAH and SHEs. Safety events occurred related to the infusion procedure and immunosuppression, including bleeding and decreased renal function. Islet transplantation should be considered for patients with T1D and IAH in whom other, less invasive current treatments have been ineffective in preventing SHEs. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Immunosuppression Therapy; Islets of Langerhans Transplantation; Male; Middle Aged; North America; Young Adult | 2016 |
Correlation Among Hypoglycemia, Glycemic Variability, and C-Peptide Preservation After Alefacept Therapy in Patients with Type 1 Diabetes Mellitus: Analysis of Data from the Immune Tolerance Network T1DAL Trial.
In natural history studies, maintenance of higher levels of C-peptide secretion (a measure of endogenous insulin production) correlates with a lower incidence of major hypoglycemic events in patients with type 1 diabetes mellitus (T1D), but it is unclear whether this is also true for drug-induced C-peptide preservation.. We analyzed hypoglycemic events and glycemic control data from the T1DAL (Inducing Remission in New-Onset T1D with Alefacept) study, a trial of alefacept in new-onset T1D, which found significant C-peptide preservation at 1 and 2 years. We performed a post hoc analysis using mixed models of the association between the meal-stimulated 4-hour C-peptide AUC (4-hour AUC) and rates of major hypoglycemia, measures of glycemic control (glycosylated hemoglobin [HbA1c]; mean glucometer readings), and variability (glucometer SDs; highest and lowest readings), and an index of partial remission (insulin dose-adjusted HbA1c[ IDAA1c]).. Data from 49 participants (33 in the alefacept group and 16 in the placebo group) were analyzed at baseline and 12 and 24 months. We found that the 4-hour AUC at baseline and at 1 year was a significant predictor of the number of hypoglycemic events during the ensuing 12-month interval (p = 0.030). There was a strong association between the 4-hour AUC and glucometer SDs (P < 0.001), highest readings (p < 0.001), and lowest readings (p = 0.03), all measures of glycemic variability. There was a strong inverse correlation between the 4-hour AUC and 2 measures of glycemic control: HbA1c and mean glucometer readings (both p < 0.001). There was also a strong inverse correlation between the 4-hour AUC and IDAA1c values (p < 0.001), as well as a strong correlation between IDAA1c values and glucometer SDs (p < 0.001), suggesting that reduced glycemic variability is associated with a trend toward partial remission. None of these analyses found a significant difference between the alefacept and placebo groups.. Measures of glycemic variability and control, including rates of hypoglycemia, are significantly correlated with preservation of C-peptide regardless of whether this is achieved by immune intervention with alefacept or natural variability in patients with new-onset T1D. Thus, preservation of endogenous insulin production by an immunomodulatory drug may confer clinical benefits similar to those seen in patients with higher C-peptide secretion due to slow disease progression. Topics: Adolescent; Adult; Alefacept; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Immune Tolerance; Insulin; Male; Recombinant Fusion Proteins; Young Adult | 2016 |
Elevations in the Fasting Serum Proinsulin-to-C-Peptide Ratio Precede the Onset of Type 1 Diabetes.
We tested whether an elevation in the serum proinsulin-to-C-peptide ratio (PI:C), a biomarker of β-cell endoplasmic reticulum (ER) dysfunction, was associated with progression to type 1 diabetes.. Fasting total PI and C levels were measured in banked serum samples obtained from TrialNet Pathway to Prevention (PTP) participants, a cohort of autoantibody-positive relatives without diabetes of individuals with type 1 diabetes. Samples were obtained ∼12 months before diabetes onset from PTP progressors in whom diabetes developed (n = 60), and were compared with age-, sex-, and BMI-matched nonprogressors who remained normoglycemic (n = 58). PI:C ratios were calculated as molar ratios and were multiplied by 100% to obtain PI levels as a percentage of C levels.. Although absolute PI levels did not differ between groups, PI:C ratios were significantly increased in antibody-positive subjects in whom there was progression to diabetes compared with nonprogressors (median 1.81% vs. 1.17%, P = 0.03). The difference between groups was most pronounced in subjects who were ≤10 years old, where the median progressor PI:C ratio was nearly triple that of nonprogressors; 90.0% of subjects in this age group within the upper PI:C quartile progressed to the development of diabetes. Logistic regression analysis, adjusted for age and BMI, demonstrated increased odds of progression for higher natural log PI:C ratio values (odds ratio 1.44, 95% CI 1.02, 2.05).. These data suggest that β-cell ER dysfunction precedes type 1 diabetes onset, especially in younger children. Elevations in the serum PI:C ratio may have utility in predicting the onset of type 1 diabetes in the presymptomatic phase. Topics: Adolescent; Adult; Autoantibodies; Biomarkers; Blood Banks; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease Progression; Fasting; Female; Humans; Longitudinal Studies; Male; Pedigree; Proinsulin; Young Adult | 2016 |
Stimulated urine C-peptide creatinine ratio vs serum C-peptide level for monitoring of β-cell function in the first year after diagnosis of Type 1 diabetes.
To determine if urine C-peptide/creatinine ratio is a useful tool for monitoring β-cell function in new-onset Type 1 diabetes.. A significant reduction in urine C-peptide/creatinine ratio, measured after a mixed-meal, was reached at 9 months (-45.4%), whilst the reduction in stimulated serum C-peptide level reached significance after 3 months (-54.7%) in placebo-treated participants. Neither change in stimulated serum C-peptide nor change in urine C-peptide level correlated with each other, and nor did change in insulin-dose-adjusted HbA. Mixed-meal-stimulated urine C-peptide/creatinine ratio was similar to, although less sensitive than, stimulated serum C-peptide level in monitoring β-cell function during the first year after diagnosis. Because the former is significantly less invasive, it warrants inclusion in further studies in Type 1 diabetes and may represent an attractive alternative outcome measure in cohort studies and in children. Topics: Adult; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Insulin-Secreting Cells; Male; Meals; Monitoring, Physiologic; Postprandial Period; Proinsulin; Time Factors; Urinalysis; Young Adult | 2016 |
Home Use of Day-and-Night Hybrid Closed-Loop Insulin Delivery in Suboptimally Controlled Adolescents With Type 1 Diabetes: A 3-Week, Free-Living, Randomized Crossover Trial.
This study evaluated the feasibility, safety, and efficacy of day-and-night hybrid closed-loop insulin delivery in adolescents with type 1 diabetes under free-living conditions.. The proportion of time that sensor glucose was in the target range (3.9-10 mmol/L; primary end point) was increased during the closed-loop intervention compared with sensor-augmented insulin pump therapy by 18.8 ± 9.8 percentage points (mean ± SD; P < 0.001), the mean sensor glucose level was reduced by 1.8 ± 1.3 mmol/L (P = 0.001), and the time spent above target was reduced by 19.3 ± 11.3 percentage points (P < 0.001). The time spent with sensor glucose levels below 3.9 mmol/L was low and comparable between interventions (median difference 0.4 [interquartile range -2.2 to 1.3] percentage points; P = 0.33). Improved glucose control during closed-loop was associated with increased variability of basal insulin delivery (P < 0.001) and an increase in the total daily insulin dose (53.5 [39.5-72.1] vs. 51.5 [37.6-64.3] units/day; P = 0.006). Participants expressed positive attitudes and experience with the closed-loop system.. Free-living home use of day-and-night closed-loop in suboptimally controlled adolescents with type 1 diabetes is safe, feasible, and improves glucose control without increasing the risk of hypoglycemia. Larger and longer studies are warranted. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Cross-Over Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male; Surveys and Questionnaires; Time Factors; Treatment Outcome; Urinalysis | 2016 |
Interleukin-1 antagonism in type 1 diabetes of long duration.
Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin-Secreting Cells; Interleukin-1beta; Middle Aged; Young Adult | 2016 |
Novel therapy for insulin-dependent diabetes mellitus: infusion of in vitro-generated insulin-secreting cells.
Insulin-dependent diabetes mellitus (IDDM) is a metabolic disease usually resulting from autoimmune-mediated β-cell destruction requiring lifetime exogenous insulin replacement. Mesenchymal stem cells (MSC) hold promising therapy. We present our experience of treating IDDM with co-infusion of in vitro autologous adipose tissue-derived MSC-differentiated insulin-secreting cells (ISC) with hematopoietic stem cells (HSC). This was an Institutional Review Board approved prospective non-randomized open-labeled clinical trial after informed consent from ten patients. ISC were differentiated from autologous adipose tissue-derived MSC and were infused with bone marrow-derived HSC in portal, thymic circulation by mini-laparotomy and in subcutaneous circulation. Patients were monitored for blood sugar levels, serum C-peptide levels, glycosylated hemoglobin (Hb1Ac) and glutamic acid decarboxylase (GAD) antibodies. Insulin administration was made on sliding scale with an objective of maintaining FBS < 150 mg/dL and PPBS around 200 mg/dL. Mean 3.34 mL cell inoculums with 5.25 × 10(4) cells/μL were infused. No untoward effects were observed. Over a mean follow-up of 31.71 months, mean serum C-peptide of 0.22 ng/mL before infusion had sustained rise of 0.92 ng/mL with decreased exogenous insulin requirement from 63.9 international units (IU)/day to 38.6 IU/day. Improvement in mean Hb1Ac was observed from 10.99 to 6.72%. Mean GAD antibodies were positive in all patients with mean of 331.10 IU/mL, which decreased to mean of 123 IU/mL. Co-infusion of autologous ISC with HSC represents a viable novel therapeutic option for IDDM. Topics: Adipose Tissue; Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Cell Differentiation; Cell- and Tissue-Based Therapy; Cells, Cultured; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Insulin; Insulin-Secreting Cells; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Middle Aged; Transplantation, Autologous | 2015 |
Glucose-dependent insulinotropic polypeptide augments glucagon responses to hypoglycemia in type 1 diabetes.
Glucose-dependent insulinotropic polypeptide (GIP) is glucagonotropic, and glucagon-like peptide-1 (GLP-1) is glucagonostatic. We studied the effects of GIP and GLP-1 on glucagon responses to insulin-induced hypoglycemia in patients with type 1 diabetes mellitus (T1DM). Ten male subjects with T1DM (C-peptide negative, age [mean ± SEM] 26 ± 1 years, BMI 24 ± 0.5 kg/m(2), HbA1c 7.3 ± 0.2%) were studied in a randomized, double-blinded, crossover study, with 2-h intravenous administration of saline, GIP, or GLP-1. The first hour, plasma glucose was lowered by insulin infusion, and the second hour constituted a "recovery phase." During the recovery phase, GIP infusions elicited larger glucagon responses (164 ± 50 [GIP] vs. 23 ± 25 [GLP-1] vs. 17 ± 46 [saline] min ⋅ pmol/L, P < 0.03) and endogenous glucose production was higher with GIP and lower with GLP-1 compared with saline (P < 0.02). On the GIP days, significantly less exogenous glucose was needed to keep plasma glucose above 2 mmol/L (155 ± 36 [GIP] vs. 232 ± 40 [GLP-1] vs. 212 ± 56 [saline] mg ⋅ kg(-1), P < 0.05). Levels of insulin, cortisol, growth hormone, and noradrenaline, as well as hypoglycemic symptoms and cognitive function, were similar on all days. Our results suggest that during hypoglycemia in patients with T1DM, exogenous GIP increases glucagon responses during the recovery phase after hypoglycemia and reduces the need for glucose administration. Topics: Adult; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Synergism; Fatty Acids, Nonesterified; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Glycerol; Hormones; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Male; Treatment Outcome | 2015 |
Postprandial glucose, insulin and incretin responses to different carbohydrate tolerance tests.
Few studies have focused on postprandial incretin responses to different carbohydrate meals. Therefore, we designed a study to compare the different effects of two carbohydrates (75 g oral glucose, a monosaccharide and 100 g standard noodle, a polysaccharide, with 75 g carbohydrates equivalently) on postprandial glucose, insulin and incretin responses in different glucose tolerance groups.. This study was an open-label, randomized, two-way crossover clinical trial. 240 participants were assigned to take two carbohydrates in a randomized order separated by a washout period of 5-7 days. The plasma glucose, insulin, c-peptide, glucagon and active glucagon-like peptide-1 (AGLP-1) were measured. The incremental area under curve above baseline from 0 to 120 min of insulin (iAUC(0 -120 min)- INS) and AGLP-1(iAUC(0 -120 min)- AGLP-1) was calculated.. Compared with standard noodles, the plasma glucose and insulin after consumption of oral glucose were higher at 30 min (both P < 0.001) and 60 min (both P < 0.001), while lower at 180 min (both P < 0.001), but no differences were found at 120 min. The glucagon at 180 min was higher after consumption of oral glucose (P = 0.010). The AGLP-1 response to oral glucose was higher at 30 min (P < 0.001), 60 min (P < 0.001) and 120 min (P = 0.022), but lower at 180 min (P = 0.027). In normal glucose tolerance (NGT), oral glucose elicited a higher insulin response to the corresponding AGLP-1 (P < 0.001), which was represented by iAUC(0 -120 min) -INS /iAUC(0 -120 min)- AGLP-1, while in type 2 diabetes mellitus (T2DM), standard noodles did (P = 0.001).. Monosaccharide potentiated more rapid and higher glycemic and insulin responses. Oral glucose of liquid state would elicit a more potent release of AGLP-1. The incretin effect was amplified after consumption of standard noodles in T2DM. Topics: Adolescent; Adult; Aged; Biomarkers; Blood Glucose; C-Peptide; China; Cross-Over Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dietary Carbohydrates; Female; Glucagon; Glucagon-Like Peptide 1; Glucose Tolerance Test; Humans; Incretins; Insulin; Male; Middle Aged; Postprandial Period; Predictive Value of Tests; Time Factors; Young Adult | 2015 |
Anti-thymocyte globulin/G-CSF treatment preserves β cell function in patients with established type 1 diabetes.
Previous efforts to preserve β cell function in individuals with type 1 diabetes (T1D) have focused largely on the use of single immunomodulatory agents administered within 100 days of diagnosis. Based on human and preclinical studies, we hypothesized that a combination of low-dose anti-thymocyte globulin (ATG) and pegylated granulocyte CSF (G-CSF) would preserve β cell function in patients with established T1D (duration of T1D >4 months and <2 years).. A randomized, single-blinded, placebo-controlled trial was performed on 25 subjects: 17 subjects received ATG (2.5 mg/kg intravenously) followed by pegylated G-CSF (6 mg subcutaneously every 2 weeks for 6 doses) and 8 subjects received placebo. The primary outcome was the 1-year change in AUC C-peptide following a 2-hour mixed-meal tolerance test (MMTT). At baseline, the age (mean ± SD) was 24.6 ± 10 years; mean BMI was 25.4 ± 5.2 kg/m²; mean A1c was 6.5% ± 1.1%; insulin use was 0.31 ± 0.22 units/kg/d; and length of diagnosis was 1 ± 0.5 years.. Combination ATG/G-CSF treatment tended to preserve β cell function in patients with established T1D. The mean difference in MMTT-stimulated AUC C-peptide between treated and placebo subjects was 0.28 nmol/l/min (95% CI 0.001-0.552, P = 0.050). A1c was lower in ATG/G-CSF-treated subjects at the 6-month study visit. ATG/G-CSF therapy was associated with relative preservation of Tregs.. Patients with established T1D may benefit from combination immunotherapy approaches to preserve β cell function. Further studies are needed to determine whether such approaches may prevent or delay the onset of the disease.. Clinicaltrials.gov NCT01106157.. The Leona M. and Harry B. Helmsley Charitable Trust and Sanofi. Topics: Adolescent; Adult; Antilymphocyte Serum; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Combinations; Female; Glycated Hemoglobin; Granulocyte Colony-Stimulating Factor; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Polyethylene Glycols; Single-Blind Method; Treatment Outcome; Young Adult | 2015 |
Insulin secretion in patients with latent autoimmune diabetes (LADA): half way between type 1 and type 2 diabetes: action LADA 9.
The study of endogenous insulin secretion may provide relevant insight into the comparison of the natural history of adult onset latent autoimmune diabetes (LADA) with types 1 and 2 diabetes mellitus. The aim of this study was to compare the results of the C-peptide response to mixed-meal stimulation in LADA patients with different disease durations and subjects with type 2 and adult-onset type 1 diabetes.. Stimulated C-peptide secretion was assessed using the mixed-meal tolerance test in patients with LADA (n = 32), type 1 diabetes mellitus (n = 33) and type 2 diabetes mellitus (n = 30). All patients were 30 to 70 years old at disease onset. The duration of diabetes in all groups ranged from 6 months to 10 years. The recruitment strategy was predefined to include at least 10 subjects in the following 3 disease onset categories for each group: 6 to 18 months, 19 months to 5 years and 5 to 10 years.. At all time-points of the mixed-meal tolerance test, patients with LADA had a lower stimulated C-peptide response than the type 2 diabetes group and a higher response than the type 1 diabetes group. The same results were found when the peak or area under the C-peptide curve was measured. When the results were stratified by time since disease onset, a similar pattern of residual insulin secretory capacity was observed.. The present study shows that the magnitude of stimulated insulin secretion in LADA is intermediate between that of type 1 and type 2 diabetes mellitus. Topics: Adult; Aged; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Meals; Middle Aged; Postprandial Period; Time Factors | 2015 |
The Effect of DPT-1 Intravenous Insulin Infusion and Daily Subcutaneous Insulin on Endogenous Insulin Secretion and Postprandial Glucose Tolerance.
To investigate the effect of parenteral insulin therapy on endogenous insulin secretion in the Diabetes Prevention Trial-Type 1 (DPT-1).. In the parenteral insulin arm of DPT-1, subjects without diabetes at high risk of future type 1 diabetes randomized to active treatment received a yearly 4-day intravenous insulin infusion (IV-I) and daily subcutaneous insulin (SC-I). To examine the effects of these insulin therapies on endogenous insulin secretion, C-peptide and glucose levels were compared during oral glucose tolerance tests (OGTTs) performed on and off IV-I and SC-I. Forty-six paired OGTTs were performed in 30 subjects from DPT-1 to determine the effect of IV-I. Twenty paired OGTTs were performed in 15 subjects from DPT-1 to determine the effect of SC-I.. IV-I suppressed fasting and OGTT-stimulated C-peptide (62% and 40%, respectively), and it significantly lowered fasting glucose (67.4 ± 4.5 mg/dL during IV-I vs. 90.9 ± 1.8 mg/dL off insulin; P < 0.05). By contrast, post-OGTT glucose levels were significantly higher during IV-I: Glucose during IV-I versus off insulin at 120 min was 203.9 ± 15.1 vs. 151.6 ± 10.2 mg/dL, respectively (P < 0.05); 49% of OGTTs became transiently diabetic (>200 mg/dL at 120 min) when receiving IV-I. Fasting glucose was significantly lower when receiving SC-I versus when off insulin (85 ± 3 vs. 94 ± 2 mg/dL, respectively; P < 0.05), but SC-I did not significantly alter fasting or OGTT-stimulated C-peptide compared with being off insulin.. These data demonstrate that the IV-I used in the DPT-1 markedly suppressed endogenous insulin secretion, which was frequently associated with postprandial glucose intolerance. SC-I, however, did not. Topics: Administration, Cutaneous; Administration, Oral; Adolescent; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucose; Glucose Intolerance; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Infusions, Intravenous; Insulin; Insulin Secretion; Male; Postprandial Period; Risk Factors; Young Adult | 2015 |
CGM-measured glucose values have a strong correlation with C-peptide, HbA1c and IDAAC, but do poorly in predicting C-peptide levels in the two years following onset of diabetes.
The aim of this work was to assess the association between continuous glucose monitoring (CGM) data, HbA1c, insulin-dose-adjusted HbA1c (IDAA1c) and C-peptide responses during the first 2 years following diagnosis of type 1 diabetes.. A secondary analysis was conducted of data collected from a randomised trial assessing the effect of intensive management initiated within 1 week of diagnosis of type 1 diabetes, in which mixed-meal tolerance tests were performed at baseline and at eight additional time points through 24 months. CGM data were collected at each visit.. Among 67 study participants (mean age [± SD] 13.3 ± 5.7 years), HbA1c was inversely correlated with C-peptide at each time point (p < 0.001), as were changes in each measure between time points (p < 0.001). However, C-peptide at one visit did not predict the change in HbA1c at the next visit and vice versa. Higher C-peptide levels correlated with increased proportion of CGM glucose values between 3.9 and 7.8 mmol/l and lower CV (p = 0.001 and p = 0.02, respectively) but not with CGM glucose levels <3.9 mmol/l. Virtually all participants with IDAA1c < 9 retained substantial insulin secretion but when evaluated together with CGM, time in the range of 3.9-7.8 mmol/l and CV did not provide additional value in predicting C-peptide levels.. In the first 2 years after diagnosis of type 1 diabetes, higher C-peptide levels are associated with increased sensor glucose levels in the target range and with lower glucose variability but not hypoglycaemia. CGM metrics do not provide added value over the IDAA1c in predicting C-peptide levels. Topics: Adolescent; Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Middle Aged; Reference Values; Young Adult | 2015 |
Insulin-secreting adipose-derived mesenchymal stromal cells with bone marrow-derived hematopoietic stem cells from autologous and allogenic sources for type 1 diabetes mellitus.
Stem cell therapy (SCT) is now the up-coming therapeutic modality for treatment of type 1 diabetes mellitus (T1DM).. Our study was a prospective, open-labeled, two-armed trial for 10 T1DM patients in each arm of allogenic and autologous adipose-derived insulin-secreting mesenchymal stromal cells (IS-AD-MSC)+bone marrow-derived hematopoietic stem cell (BM-HSC) infusion. Group 1 received autologous SCT: nine male patients and one female patient; mean age, 20.2 years, disease duration 8.1 years; group 2 received allogenic SCT: six male patients and four female patients, mean age, 19.7 years and disease duration, 7.9 years. Glycosylated hemoglobin (HbA1c) was 10.99%; serum (S.) C-peptide, 0.22 ng/mL and insulin requirement, 63.9 IU/day in group 1; HbA1c was 11.93%, S.C-peptide, 0.028 ng/mL and insulin requirement, 57.55 IU/day in group 2. SCs were infused into the portal+thymic circulation and subcutaneous tissue under non-myelo-ablative conditioning. Patients were monitored for blood sugar, S.C-peptide, glutamic acid decarboxylase antibodies and HbA1c at 3-month intervals.. Group 1 received mean SCs 103.14 mL with 2.65 ± 0.8 × 10(4) ISCs/kg body wt, CD34+ 0.81% and CD45-/90+/73+, 81.55%. Group 2 received mean SCs 95.33 mL with 2.07 ± 0.67 × 10(4) ISCs/kg body wt, CD34+ 0.32% and CD45-/90+/73+ 54.04%. No untoward effect was observed with sustained improvement in HbA1c and S.C-peptide in both groups with a decrease in glutamic acid decarboxylase antibodies and reduction in mean insulin requirement.. SCT is a safe and viable treatment option for T1DM. Autologous IS-AD-MSC+ BM-HSC co-infusion offers better long-term control of hyperglycemia as compared with allogenic SCT. Topics: Adipose Tissue; Adult; Blood Glucose; Bone Marrow Cells; C-Peptide; Cell- and Tissue-Based Therapy; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Insulin; Insulin Secretion; Leukocyte Common Antigens; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Obesity; Prospective Studies; Subcutaneous Fat; Young Adult | 2015 |
Effects of insulin degludec and insulin glargine on day-to-day fasting plasma glucose variability in individuals with type 1 diabetes: a multicentre, randomised, crossover study.
We compared the effects of insulin degludec (IDeg; Des(B30)LysB29(γ-Glu Nε-hexadecandioyl) human insulin) and insulin glargine (IGlar; A21Gly,B31Arg,B32Arg human insulin) on the day-to-day variability of fasting plasma glucose (FPG) levels in individuals with type 1 diabetes treated with basal-bolus insulin injections.. The effects of basal-bolus insulin therapy for 4 weeks with either IDeg or IGlar as the basal insulin in adult C-peptide-negative outpatients with type 1 diabetes were investigated in an open-label, multicentre, randomised, crossover trial. Randomisation was conducted using a centralised allocation process. The primary endpoints were the SD and CV of FPG during the final week of each treatment period. Secondary endpoints included serum glycoalbumin level, daily dose of insulin, intraday glycaemic variability and frequency of severe hypoglycaemia.. Thirty-six randomised participants (17 in the IDeg/IGlar and 19 in the IGlar/IDeg groups) were recruited, and data for 32 participants who completed the trial were analysed. The mean (7.74 ± 1.76 vs 8.56 ± 2.06 mmol/l; p = 0.04) and SD (2.60 ± 0.97 vs 3.19 ± 1.36 mmol/l; p = 0.03) of FPG were lower during IDeg treatment than during IGlar treatment, whereas the CV did not differ between the two treatments. The dose of IDeg was smaller than that of IGlar (11.0 ± 5.2 vs 11.8 ± 5.6 U/day; p < 0.01), but other secondary endpoints did not differ between the treatments.. IDeg yielded a lower FPG level and smaller day-to-day variability of FPG at a lower daily dose compared with IGlar in participants with type 1 diabetes. IDeg serves as a good option for basal insulin in the treatment of type 1 diabetes.. University Hospital Medical Information Network 000009965.. This research recieved no specific grant from any funding agency in the public, commercial or not-for-profit sectors. Topics: Adult; Aged; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Glargine; Insulin Secretion; Insulin, Long-Acting; Insulin, Regular, Human; Male; Middle Aged; Reproducibility of Results | 2015 |
Alefacept provides sustained clinical and immunological effects in new-onset type 1 diabetes patients.
Type 1 diabetes (T1D) results from destruction of pancreatic β cells by autoreactive effector T cells. We hypothesized that the immunomodulatory drug alefacept would result in targeted quantitative and qualitative changes in effector T cells and prolonged preservation of endogenous insulin secretion by the remaining β cells in patients with newly diagnosed T1D.. In a multicenter, randomized, double-blind, placebo-controlled trial, we compared alefacept (two 12-week courses of 15 mg/wk i.m., separated by a 12-week pause) with placebo in patients with recent onset of T1D. Endpoints were assessed at 24 months and included meal-stimulated C-peptide AUC, insulin use, hypoglycemic events, and immunologic responses.. A total of 49 patients were enrolled. At 24 months, or 15 months after the last dose of alefacept, both the 4-hour and the 2-hour C-peptide AUCs were significantly greater in the treatment group than in the control group (P = 0.002 and 0.015, respectively). Exogenous insulin requirements were lower (P = 0.002) and rates of major hypoglycemic events were about 50% reduced (P < 0.001) in the alefacept group compared with placebo at 24 months. There was no apparent between-group difference in glycemic control or adverse events. Alefacept treatment depleted CD4+ and CD8+ central memory T cells (Tcm) and effector memory T cells (Tem) (P < 0.01), preserved Tregs, increased the ratios of Treg to Tem and Tcm (P < 0.01), and increased the percentage of PD-1+CD4+ Tem and Tcm (P < 0.01).. In patients with newly diagnosed T1D, two 12-week courses of alefacept preserved C-peptide secretion, reduced insulin use and hypoglycemic events, and induced favorable immunologic profiles at 24 months, well over 1 year after cessation of therapy.. https://clinicaltrials.gov/ NCT00965458.. NIH and Astellas. Topics: Adolescent; Adult; Alefacept; C-Peptide; CD4 Lymphocyte Count; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Child; Dermatologic Agents; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Humans; Immunologic Memory; Male; Recombinant Fusion Proteins; Time Factors | 2015 |
Cholecalciferol supplementation improves suppressive capacity of regulatory T-cells in young patients with new-onset type 1 diabetes mellitus - A randomized clinical trial.
It is unknown if cholecalciferol is able to modify defects in regulatory T cells (Tregs) in type 1 diabetes (T1D). In this randomized, double-blind, placebo controlled trial 30 young patients with new-onset T1D were assigned to cholecalciferol (70IU/kgbodyweight/day) or placebo for 12months. Tregs were determined by FACS-analysis and functional tests were assessed with ex vivo suppression co-cultures at months 0, 3, 6 and 12. Suppressive capacity of Tregs increased (p<0.001) with cholecalciferol from baseline (-1.59±25.6%) to 3 (30.5±39.4%), 6 (44.6±23.8%) and 12months (37.2±25.0%) and change of suppression capacity from baseline to 12months was significantly higher (p<0.05) with cholecalciferol (22.2±47.2%) than placebo (-16.6±21.1%). Serum calcium and parathormone stayed within normal range. This is the first study, which showed that cholecalciferol improved suppressor function of Tregs in patients with T1D and vitamin D could serve as one possible agent in the development of immunomodulatory combination therapies for T1D. Topics: Adolescent; C-Peptide; Child; Cholecalciferol; Diabetes Mellitus, Type 1; Dietary Supplements; Double-Blind Method; Fasting; Female; Humans; Male; Pilot Projects; Prospective Studies; T-Lymphocytes, Regulatory; Time Factors; Treatment Outcome; Vitamins | 2015 |
[Clinical observation on the combined therapy of sitagliptin with insulin for patients with brittle diabetes].
To observe the clinical efficacy of sitagliptin plus insulin on patients with brittle diabetes and to determine the effect of the combined therapy on glucagon secretion. . This randomized, double-blinded and placebo-controlled trial included 30 patients with brittle diabetes. Participants were randomly assigned (1:1) to receive the treatment of either sitagliptin plus insulin or placebo plus insulin for 12 weeks. The blood glucose, hemoglobin A1c, insulin dose, C-peptide, glucagon, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and other parameters were determined. . After 12 weeks of treatment, blood glucose was controlled better by sitagliptin plus insulin (P<0.01). The patients had significantly lower glucose variability indices, lower daily insulin requirement and hemoglobin A1c in the group of sitagliptin plus insulin (P<0.01). After steamed bun test, past-meal GLP-1 levels at 30 min were higher (P<0.01) while GIP levels were lower (P<0.01), with glucagon suppression in the sitagliptin plus insulin group. No significant change was observed at any time point in placebo plus insulin group. . Sitagliptin significantly decreases blood glucose level and blood glucose fluctuation, which may contribute to the ability of sitagliptin in decreasing glucagon secretion.. 目的:观察西格列汀联合胰岛素治疗脆性糖尿病的临床疗效以及二者联合治疗对胰高血糖素的影响。方法:对30例脆性糖尿病患者进行1:1随机双盲分组,分为西格列汀联合胰岛素组和安慰剂联合胰岛素组,治疗12周,观察治疗后患者的血糖控制、血糖波动、糖化血红蛋白、胰岛素剂量、C肽、胰高血糖素、胰高血糖素样肽-1 (glucagon-like peptide-1,GLP-1)和葡萄糖依赖性促胰岛素肽(glucose-dependent insulinotropic polypeptide,GIP)水平等指标的变化。结果:治疗脆性糖尿病患者12周后,西格列汀联合胰岛素组血糖控制的水平和达标率明显优于治疗前和安慰剂联合胰岛素组(P<0.01);胰岛素用量和糖化血红蛋白较治疗前和安慰剂联合胰岛素组明显减少(P<0.01);行馒头餐试验,餐后30 min西格列汀联合胰岛素组的胰高血糖素和GIP水平明显低于治疗前和安慰剂联合胰岛素组(P<0.01),而GLP-1(60 min)水平较治疗前和安慰剂联合胰岛素组升高(P<0.05)。安慰剂联合胰岛素组各指标在治疗前后比较,差异无统计学意义(P>0.05)。结论:在加用西格列汀后,能够更好地控制脆性糖尿病患者血糖和降低血糖波动的幅度;可能是通过降低餐后胰高血糖素水平来稳定脆性糖尿病患者的血糖水平。. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dipeptidyl-Peptidase IV Inhibitors; Double-Blind Method; Drug Therapy, Combination; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Sitagliptin Phosphate | 2015 |
Modulation of Autoimmune T-Cell Memory by Stem Cell Educator Therapy: Phase 1/2 Clinical Trial.
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that causes a deficit of pancreatic islet β cells. The complexities of overcoming autoimmunity in T1D have contributed to the challenges the research community faces when devising successful treatments with conventional immune therapies. Overcoming autoimmune T cell memory represents one of the key hurdles.. In this open-label, phase 1/phase 2 study, Caucasian T1D patients (N = 15) received two treatments with the Stem Cell Educator (SCE) therapy, an approach that uses human multipotent cord blood-derived multipotent stem cells (CB-SCs). SCE therapy involves a closed-loop system that briefly treats the patient's lymphocytes with CB-SCs in vitro and returns the "educated" lymphocytes (but not the CB-SCs) into the patient's blood circulation. This study is registered with ClinicalTrials.gov, NCT01350219.. Clinical data demonstrated that SCE therapy was well tolerated in all subjects. The percentage of naïve CD4(+) T cells was significantly increased at 26 weeks and maintained through the final follow-up at 56 weeks. The percentage of CD4(+) central memory T cells (TCM) was markedly and constantly increased at 18 weeks. Both CD4(+) effector memory T cells (TEM) and CD8(+) TEM cells were considerably decreased at 18 weeks and 26 weeks respectively. Additional clinical data demonstrated the modulation of C-C chemokine receptor 7 (CCR7) expressions on naïve T, TCM, and TEM cells. Following two treatments with SCE therapy, islet β-cell function was improved and maintained in individuals with residual β-cell function, but not in those without residual β-cell function.. Current clinical data demonstrated the safety and efficacy of SCE therapy in immune modulation. SCE therapy provides lasting reversal of autoimmune memory that could improve islet β-cell function in Caucasian subjects.. Obra Social "La Caixa", Instituto de Salud Carlos III, Red de Investigación Renal, European Union FEDER Funds, Principado de Asturias, FICYT, and Hackensack University Medical Center Foundation. Topics: Adult; Autoimmunity; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Gene Expression; Humans; Immunologic Memory; Immunomodulation; Insulin-Secreting Cells; Islets of Langerhans; Male; Middle Aged; Receptors, CCR7; Stem Cell Transplantation; Stem Cells; T-Lymphocyte Subsets; Treatment Outcome; Young Adult | 2015 |
Characterization of residual β cell function in long-standing type 1 diabetes.
Some patients with long-standing type 1 diabetes (T1D) maintain detectable levels of C-peptide. The quantitative and qualitative aspects of insulin secretion in these subjects have not been assessed, but may shed light on the basis for maintained β cell function. Our objective was to characterize insulin secretion in subjects with varying duration of T1D.. Data from mixed-meal tolerance tests were collected in this cross-sectional study. We screened 58 subjects with T1D <1 year and 34 subjects with T1D >2 years, 20 of whom had previously participated in trials of anti-CD3 monoclonal antibody. Data from 38 historical non-diabetic controls were utilized. Insulin secretory rates were calculated from C-peptide levels from mixed-meal tolerance tests. Patterns and rates of insulin secretion were characterized along with relationships between insulin secretion and clinical parameters.. C-peptide was detected in 68% of subjects with T1D duration >2 years. Insulin secretion was negatively correlated with HgbA(1c) and insulin use. A decline in total insulin secretion was seen with increasing disease duration (p < 0.0001). More subjects with long duration of T1D had a delayed time to peak secretion compared with those with new onset T1D or non-diabetic subjects. Insulin and glucagon secretory responses appeared unrelated.. Meal-stimulated insulin secretory responses are seen in those with long-standing T1D and detectable C-peptide. Delayed insulin secretory responses are more common in individuals with longer disease duration. Residual insulin secretory responses are associated with improved clinical parameters. Topics: Adolescent; Adult; C-Peptide; Child; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Disease Progression; Down-Regulation; Female; Glucagon; Glucagon-Secreting Cells; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Postprandial Period; Young Adult | 2014 |
Efficacy and safety of low-dose otelixizumab anti-CD3 monoclonal antibody in preserving C-peptide secretion in adolescent type 1 diabetes: DEFEND-2, a randomized, placebo-controlled, double-blind, multi-centre study.
Phase III DEFEND-2 investigated whether otelixizumab (3.1 mg over 8 days) preserved C-peptide secretion in patients with new-onset Type 1 diabetes, focusing on adolescents (12-17 years).. One hundred and seventy-nine patients (54 adolescents) were randomized to otelixizumab or placebo. The primary endpoint was change in 2-h mixed-meal-stimulated C-peptide area under the curve at month 12. Enrolment was suspended in April 2011 following negative efficacy results from DEFEND-1. DEFEND-2 terminated early after 12 months' efficacy and safety follow-up.. Change from baseline C-peptide was not significantly different [∆ = -0.09 nmol/l (95% CI -0.17 to 0; P = 0.051)]. No differential C-peptide effect was seen for otelixizumab in adolescents and more adverse events were reported.. Efficacy and tolerability of otelixizumab was similar to DEFEND-1. The 3.1-mg dose was non-efficacious in adults and adolescents. Further investigation of the mechanism of action seen at higher doses and therapeutic window is required. Clinical Trials Registry No: NCT 00763451. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Early Termination of Clinical Trials; Female; Humans; Male; Treatment Outcome | 2014 |
Costimulation modulation with abatacept in patients with recent-onset type 1 diabetes: follow-up 1 year after cessation of treatment.
OBJECTIVE We previously reported that 2 years of costimulation modulation with abatacept slowed decline of β-cell function in recent-onset type 1 diabetes (T1D). Subsequently, abatacept was discontinued and subjects were followed to determine whether there was persistence of effect. RESEARCH DESIGN AND METHODS Of 112 subjects (ages 6-36 years) with T1D, 77 received abatacept and 35 received placebo infusions intravenously for 27 infusions over 2 years. The primary outcome-baseline-adjusted geometric mean 2-h area under the curve (AUC) serum C-peptide during a mixed-meal tolerance test (MMTT) at 2 years-showed higher C-peptide with abatacept versus placebo. Subjects were followed an additional year, off treatment, with MMTTs performed at 30 and 36 months. RESULTS C-peptide AUC means, adjusted for age and baseline C-peptide, at 36 months were 0.217 nmol/L (95% CI 0.168-0.268) and 0.141 nmol/L (95% CI 0.071-0.215) for abatacept and placebo groups, respectively (P = 0.046). The C-peptide decline from baseline remained parallel with an estimated 9.5 months' delay with abatacept. Moreover, HbA1c levels remained lower in the abatacept group than in the placebo group. The slightly lower (nonsignificant) mean total insulin dose among the abatacept group reported at 2 years was the same as the placebo group by 3 years. CONCLUSIONS Costimulation modulation with abatacept slowed decline of β-cell function and improved HbA1c in recent-onset T1D. The beneficial effect was sustained for at least 1 year after cessation of abatacept infusions or 3 years from T1D diagnosis. Topics: Abatacept; Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Immunoconjugates; Immunosuppressive Agents; Male; Placebos; Withholding Treatment; Young Adult | 2014 |
GAD-treatment of children and adolescents with recent-onset type 1 diabetes preserves residual insulin secretion after 30 months.
This study aimed to analyse data from two different studies (phase II and phase III) regarding the safety and efficacy of treatment with alum formulated glutamic acid decarboxylase GAD65 (GAD-alum) at 30 months after administration to children and adolescents with type 1 diabetes.. The phase II trial was a double-blind, randomised placebo-controlled study, including 70 children and adolescents who were followed for 30 months. Participants received a subcutaneous injection of either 20 µg of GAD-alum or placebo at baseline and 1 month later. During a subsequent larger European phase III trial including three treatment arms, participants received two or four subcutaneous injections of either 20 µg of GAD-alum and/or placebo at baseline, 1, 3 and 9 months. The phase III trial was prematurely interrupted at 15 months, but of the 148 Swedish patients, a majority completed the 21 months follow-up, and 45 patients completed the trial at 30 months. Both studies included GAD65 auto-antibodies-positive patients with fasting C-peptide ≥ 0.10 nmol/l. We have now combined the results of these two trials.. There were no treatment related adverse events. In patients treated with 2 GAD-alum doses, stimulated C-peptide area under the curve had decreased significantly less (9 m: p < 0.037; 15 m: p < 0.032; 21 m: p < 0.003 and 30 m: p < 0.004), and a larger proportion of these patients were also able to achieve a peak stimulated C-peptide > 0.2 nmol/L (p < 0.05), as compared with placebo.. Treatment with two doses of GAD-alum in children and adolescents with recent-onset type 1 diabetes shows no adverse events and preserves residual insulin secretion. Topics: Adolescent; Alum Compounds; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Insulin Secretion; Male; Young Adult | 2014 |
Evaluation of long-term treatment effect in a type 1 diabetes intervention trial: differences after stimulation with glucagon or a mixed meal.
Endogenous insulin secretion, measured by C-peptide area under the curve (AUC), can be tested using both the glucagon stimulation test (GST) and the mixed-meal tolerance test (MMTT). This study compares these two stimulation methods using long-term data from patients newly diagnosed with type 1 diabetes or with latent autoimmune diabetes.. A recently completed phase 3 intervention study with DiaPep277 demonstrated improved glycemic control and a significant treatment effect of glucagon-stimulated C-peptide secretion. Unexpectedly, MMTT failed to detect differences between the treated and control groups. Data from 343 patients in two balanced-randomized, double-blind, placebo-controlled, parallel-group trials of DiaPep277 were used to compare and correlate between GST- and MMTT-derived C-peptide AUC. Pearson's correlations were calculated for absolute C-peptide AUC at baseline and 12 and 24 months and for long-term changes in AUC (AUC).. The absolute AUC values obtained at any single time point by the two tests were well correlated in both data sets (r = 0.74-0.9). However, the correlations between the AUC were much weaker (r = 0.39-0.58). GST-stimulated C-peptide secretion was stable over the fasting glucose range permitted for the test (4-11.1 mmol/L), but MMTT-stimulated C-peptide secretion decreased over the same range, implying differences in sensitivity to glucose.. Measurement of long-term changes in stimulated C-peptide, reflecting endogenous insulin secretion, during the course of intervention trials may be affected by the method of stimulation, possibly reflecting different sensitivities to the physiological status of the tested subject. Topics: Adolescent; Adult; Area Under Curve; Blood Glucose; C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Double-Blind Method; Fasting; Female; Food; Gastrointestinal Agents; Glucagon; Glucose; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Meals; Middle Aged; Peptide Fragments; Young Adult | 2014 |
GAD autoantibody affinity in adult patients with latent autoimmune diabetes, the study participants of a GAD65 vaccination trial.
Patients with latent autoimmune diabetes in adults (LADA) express autoantibodies against the 65-kDa isoform of GAD (GADA). Intervention with recombinant human GAD65 formulated with aluminium hydroxide (GAD-alum) given twice subcutaneously to LADA patients at intervals of 4 weeks was safe and did not compromise β-cell function in a Phase II clinical trial. GADA affinity has been shown to predict progression to type 1 diabetes. Here, we asked whether GADA affinity was affected by the GAD65 antigen-specific vaccination and/or associated with β-cell function in participants of this trial.. GADA affinity was measured in sera of 46 LADA patients obtained prior to the first week and 20 weeks after the second injection with GAD-alum or placebo using competitive binding experiments with [125I]-labeled and unlabeled human GAD65.. At baseline, GADA affinities ranged from 1.9 × 10(7) to 5.0 × 10(12) L/mol (median 2.8 × 10(10) L/mol) and were correlated with GADA titers (r = 0.47; P = 0.0009), fasting (r = -0.37; P = 0.01) and stimulated (r = -0.40; P = 0.006) C-peptide concentrations, and HbA1c (r = 0.39; P = 0.007). No significant changes in affinity were observed from baseline to week 24. Patients with GADA affinities in the lower first quartile (<4 × 10(9) L/mol) had better preserved fasting C-peptide concentrations at baseline than those with higher affinities (mean 1.02 vs. 0.66 nmol/L; P = 0.004) and retained higher concentrations over 30 months of follow-up (mean 1.26 vs. 0.62 nmol/L; P = 0.01).. Intervention with GAD-alum in LADA patients had no effect on GADA affinity. Our data suggest that patients with low GADA affinity have a prolonged preservation of residual β-cell function. Topics: Adult; Aged; Alum Compounds; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Double-Blind Method; Female; Glucose Intolerance; Glutamate Decarboxylase; Humans; Insulin-Secreting Cells; Male; Middle Aged; Vaccination; Vaccines, Synthetic | 2014 |
Therapy of type 1 diabetes with CD4(+)CD25(high)CD127-regulatory T cells prolongs survival of pancreatic islets - results of one year follow-up.
It is hypothesized that CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) can prevent destruction of pancreatic islets protecting from type 1 diabetes (DM1). Here we present results of one year follow-up of 12 DM1 children treated with autologous expanded ex vivo Tregs. Patients received either a single or double Tregs infusion up to the total dose of 30×10(6)/kg. No severe adverse effects were observed. The treatment did not impair post-immunization antibody responses. Tregs infusion was followed by increase in Tregs number in peripheral blood. Most of the patients responded to the therapy with increase in C-peptide levels (8/12 and 4/6 after the first and the second dose, respectively). Tregs administration resulted also in lower requirement for exogenous insulin (8/12 treated patients versus 2/10 untreated controls in remission) with two children completely insulin independent at one year. Repetitive administration of Tregs is safe and can prolong survival of β-cells in DM1 (registration: ISRCTN06128462). Topics: Adolescent; C-Peptide; Cell- and Tissue-Based Therapy; Child; Child, Preschool; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Interleukin-2 Receptor alpha Subunit; Interleukin-7 Receptor alpha Subunit; Islets of Langerhans Transplantation; Risk Factors; T-Lymphocytes, Regulatory; Treatment Outcome | 2014 |
Clinical characteristics and long-term follow-up of ketosis-prone diabetes in Thai patients.
Diabetes presenting with ketoacidosis is a heterogeneous disorder. The purpose of this study was to determine whether ketosis-prone diabetes (KPDM) in Thai patients were different from type1 diabetes by assessment of the beta-cell response to a standardized mixed meal and pancreatic autoantibodies.. 20 patients who were categorized as ketosis-prone diabetes based on the occurrence of unprovoked DKA after the age of 30 years were compared with 12 type1 diabetic patients. The beta-cell function and pancreatic autoantibodies were followed after resolution of DKA every 6 months for 2 years.. Mean (±SD) age at presentation was 38.8±11.5 and 26.7+10.3 years in KPDM and type1 DM, respectively (p<0.05). Median (IQR) fasting plasma C-peptide obtained after resolution of DKA within 2 weeks was 0.90 ng/dl -(0.20-1.30) in KPDM compared with 0.10 ng/dl (0.10-0.45) in type1 diabetes and median peak stimulated plasma C-peptide was 6.80 ng/dl (0.90-9.80) compared with 0.10 ng/dl (0.10-0.75). Based on Aβ classification, 4 patients were classified as A+β-, 12 patients were classified as A-β+, and 4 patients were classified as A-β-. No patient was classified as A+β+ in this study. At the median time of 31 months follow-up (range from 8-44 months), 11 patients from 12 A-β+ KPDM (92%) could be withdrawn from insulin treatment successfully at median time of 5 months after admission.. Thai KPDM patients had variable clinical course which were different from typical type1 DM. The Aβ classification was proven to be useful predictors for consideration of insulin withdrawal after resolution of DKA. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Prospective Studies; Thailand | 2014 |
Distribution of C-peptide and its determinants in North American children at risk for type 1 diabetes.
To determine basal and stimulated C-peptide percentiles in North American children and adolescents at risk for type 1 diabetes (T1D) and to examine factors associated with this distribution in the Diabetes Prevention Trial-Type 1 (DPT-1).. We included 582 subjects aged 4-18 years at randomization in the DPT-1 trials. A 2-h oral glucose tolerance test (OGTT) was performed at baseline and every 6 months during the 5-year follow-up period. The percentile values of C-peptide after baseline OGTT were estimated according to age, BMI Z score (BMIZ), and/or sex categories. Conditional quantile regression was used to examine the relationship between C-peptide percentiles and various independent variables.. The basal and stimulated C-peptide levels increased significantly as age and BMIZ increased (P < 0.05). Both age and BMIZ had a stronger impact on the upper quartile of C-peptide distributions than the lower quartile. Sex was only significantly associated with stimulated C-peptide. Higher stimulated C-peptide levels were generally observed in girls compared with boys at the same age and BMIZ (P < 0.05). HLA type and number of positive antibodies and antibody titers (islet cell antibody [ICA], insulin autoantibody, GAD65A, and ICA512A) were not significantly associated with C-peptide distribution after adjustment for age, BMIZ, and sex.. Age-, sex-, and BMIZ-specific C-peptide percentiles can be estimated for North American children and adolescents at risk for T1D. They can be used as an assessment tool that could impact the recommendations in T1D prevention trials. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin Antibodies; Male; North America; Risk | 2014 |
Importance of exercise in the control of metabolic and inflammatory parameters at the moment of onset in type 1 diabetic subjects.
The onset of type 1 diabetes coincides with the final phase of β-cell destruction. In some cases, this period is characterized by the presence of a functional reserve of β-cells, favouring an adequate metabolic control (honeymoon phase). Therefore, the extension of this situation could have evident benefits in subsequent diabetes management. We aimed to study the influence of regular physical activity before and after the onset of the disease. We did an observational study of 2 groups of type 1 diabetic patients from onset to a 2-year period. One group (n = 8) exercised regularly (5 or more hours/week) before onset and continued doing so with the same regularity. The second group (n = 11) either did not perform physical activity or did so sporadically. Circulating glycated haemoglobin (HbA1c), C-peptide, protein carbonyls and basal cytokine levels were determined at the beginning and at the end of the 1(st) and 2(nd) year. The more active group debuted with and maintained significantly lower HbA(1c) levels and insulin requirements compared to the more sedentary group. C-peptide levels were only significantly higher in the active group at the moment of onset compared to the sedentary group. In addition, determination of basal circulating cytokines revealed a large variability between individuals but no significant differences when comparing the groups. Altogether, the obtained results seem to indicate that physical activity allows a better control at the moment of onset regarding glycaemic control, residual endocrine pancreatic mass and subsequent insulin requirements. Topics: Age of Onset; C-Peptide; Cytokines; Diabetes Mellitus, Type 1; Exercise Therapy; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Inflammation; Male; Pilot Projects; Time Factors | 2014 |
Reduction in CD4 central memory T-cell subset in costimulation modulator abatacept-treated patients with recent-onset type 1 diabetes is associated with slower C-peptide decline.
We previously reported that continuous 24-month costimulation blockade by abatacept significantly slows the decline of β-cell function after diagnosis of type 1 diabetes. In a mechanistic extension of that study, we evaluated peripheral blood immune cell subsets (CD4, CD8-naive, memory and activated subsets, myeloid and plasmacytoid dendritic cells, monocytes, B lymphocytes, CD4(+)CD25(high) regulatory T cells, and invariant NK T cells) by flow cytometry at baseline and 3, 6, 12, 24, and 30 months after treatment initiation to discover biomarkers of therapeutic effect. Using multivariable analysis and lagging of longitudinally measured variables, we made the novel observation in the placebo group that an increase in central memory (CM) CD4 T cells (CD4(+)CD45R0(+)CD62L(+)) during a preceding visit was significantly associated with C-peptide decline at the subsequent visit. These changes were significantly affected by abatacept treatment, which drove the peripheral contraction of CM CD4 T cells and the expansion of naive (CD45R0(-)CD62L(+)) CD4 T cells in association with a significantly slower rate of C-peptide decline. The findings show that the quantification of CM CD4 T cells can provide a surrogate immune marker for C-peptide decline after the diagnosis of type 1 diabetes and that costimulation blockade may exert its beneficial therapeutic effect via modulation of this subset. Topics: Abatacept; Adolescent; Adult; C-Peptide; CD4-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; Humans; Immunoconjugates; Immunologic Memory; Immunosuppressive Agents; Male; Middle Aged; T-Lymphocyte Subsets; Young Adult | 2014 |
Insulin secretion measured by stimulated C-peptide in long-established Type 1 diabetes in the Diabetes Control and Complications Trial (DCCT)/ Epidemiology of Diabetes Interventions and Complications (EDIC) cohort: a pilot study.
To evaluate whether clinically relevant concentrations of stimulated C-peptide in response to a mixed-meal tolerance test can be detected after almost 30 years of diabetes in people included in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications cohort.. Mixed-meal tolerance tests were performed in a sample of 58 people. C-peptide levels were measured using a chemiluminescent immunoassay. This sample size assured a high probability of detecting C-peptide response if the true prevalence was at least 5%, a level that would justify the subsequent assessment of C-peptide in the entire cohort.. Of the 58 participants, 17% showed a definite response, defined as one or more post-stimulus concentrations of C-peptide > 0.03 nmol/l, and measurable concentrations were found in all participants.. These results show that a stimulated C-peptide response can be measured in some people with long-term Type 1 diabetes. Further investigation of all participants in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications study will help relate long-term residual C-peptide response to glycaemia over time and provide insight into the relevance of this response in terms of insulin dose, severe hypoglycaemia, retinopathy, nephropathy and macrovascular disease. Establishing the clinical relevance of long-term C-peptide responses is important in understanding the impact that therapy to preserve or improve β-cell function may have in patients with long-term Type 1 diabetes. Topics: C-Peptide; Canada; Cohort Studies; Diabetes Complications; Diabetes Mellitus, Type 1; Disease Progression; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Incidence; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Pilot Projects; Postprandial Period; United States | 2014 |
Autologous nonmyeloablative hematopoietic stem cell transplantation in new-onset type 1 diabetes: a multicenter analysis.
Type 1 diabetes (T1D) is one of the major autoimmune diseases affecting children and young adults worldwide. To date, the different immunotherapies tested have achieved insulin independence in <5% of treated individuals. Recently, a novel hematopoietic stem cell (HSC)-based strategy has been tested in individuals with new-onset T1D. The aim of this study was to determine the effects of autologous nonmyeloablative HSC transplantation in 65 individuals with new-onset T1D who were enrolled in two Chinese centers and one Polish center, pooled, and followed up for 48 months. A total of 59% of individuals with T1D achieved insulin independence within the first 6 months after receiving conditioning immunosuppression therapy (with antithymocyte globulin and cyclophosphamide) and a single infusion of autologous HSCs, and 32% remained insulin independent at the last time point of their follow-up. All treated subjects showed a decrease in HbA1c levels and an increase in C-peptide levels compared with pretreatment. Despite a complete immune system recovery (i.e., leukocyte count) after treatment, 52% of treated individuals experienced adverse effects. Our study suggests the following: 1) that remission of T1D is possible by combining HSC transplantation and immunosuppression; 2) that autologous nonmyeloablative HSC transplantation represents an effective treatment for selected individuals with T1D; and 3) that safer HSC-based therapeutic options are required. Topics: Adolescent; Adult; C-Peptide; Child; Cyclophosphamide; Diabetes Mellitus, Type 1; Female; Hematopoietic Stem Cell Transplantation; Humans; Immunosuppression Therapy; Insulin; Male; Remission Induction; Transplantation, Autologous | 2014 |
Low-dose otelixizumab anti-CD3 monoclonal antibody DEFEND-1 study: results of the randomized phase III study in recent-onset human type 1 diabetes.
Previous studies demonstrated that the anti-CD3 monoclonal antibody otelixizumab, administered at a total dose of 48-64 mg, can slow the loss of C-peptide in recent-onset type 1 diabetes patients, with frequent reactivation of Epstein Barr virus (EBV). The DEFEND-1 (Durable Response Therapy Evaluation for Early or New-Onset Type 1 Diabetes) trial was designed to test whether a lower dose of otelixizumab could preserve C-peptide secretion in new-onset type 1 diabetes patients.. A multicenter, randomized, placebo-controlled trial was performed in sites in the U.S., Canada, and Europe. Two hundred eighty-one patients were randomized to treatment with 3.1 mg otelixizumab administered over 8 days or placebo. The primary end point of the study was the change in C-peptide area under the curve (AUC) from a 2-h mixed-meal tolerance test at month 12.. The change in 2-h C-peptide AUC was not different between placebo-treated patients and otelixizumab-treated patients (-0.20 vs. -0.22 nmol/L, P = 0.81). Secondary end points, including HbA1c, glucose variability, and insulin dose, were also not statistically different between the two groups. More patients in the otelixizumab group than in the placebo group experienced adverse events, mostly grade 1 or grade 2. There was no EBV reactivation (viral load >10,000 copies/10(6) peripheral blood mononuclear cells) in the otelixizumab group, in contrast with previously published studies at higher doses of otelixizumab.. Otelixizumab was well tolerated in patients with recent-onset type 1 diabetes at a total dose of 3.1 mg, but did not achieve preservation of levels of C-peptide or other markers of metabolic control. Topics: Adolescent; Adult; Age of Onset; Antibodies, Monoclonal, Humanized; C-Peptide; Canada; CD3 Complex; Child; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Europe; Female; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; United States; Young Adult | 2014 |
Five-year follow-up of patients with type 1 diabetes transplanted with allogeneic islets: the UIC experience.
This report summarizes a 5-year phase 1/2 allogeneic islet transplantation clinical trial conducted at the University of Illinois at Chicago (UIC). Ten patients were enrolled in this single center, open label, and prospective trial in which patients received 1-3 transplants. The first four subjects underwent islet transplantation with the Edmonton immunosuppressive regimen and the remaining six subjects received the UIC immunosuppressive protocol (Edmonton plus etanercept and exenatide). All 10 patients achieved insulin independence after 1-3 transplants. At 5 years of follow-up, 6 of the initial 10 patients were free of exogenous insulin. During the follow-up period, 7 of the 10 patients maintained positive C-peptide levels and a composite hypoglycemic score of 0. Most patients maintained HbA1c levels <6.0 % (42.1 mmol/mol) and a significantly improved β-score. In conclusion, this study demonstrated long-term islet graft function without using T cell depleting induction, with an encouraging outcome that includes 60 % of patients remaining insulin independent after 5 years of initial transplantation. Topics: Adult; Aged; Blood Glucose; C-Peptide; Chicago; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Hospitals, University; Humans; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Prospective Studies; Transplantation, Homologous | 2014 |
[The content of individual fatty acids and numbers of double bonds, insulin, C-peptide and unesterified fatty acids in blood plasma in testing tolerance to glucose].
The glucose tolerance test demonstrates that content of unesterified fatty acids in blood plasma decreases up to three times and the content of oleic and linoleic acids is more decreased in the pool of fatty acids lipids. Out of resistance to insulin, hormone secretion increases up to three times. The decreasing of level of individual fatty acids occurs in a larger extent. Under resistance to insulin secretion of insulin is increasing up to eight times. The decreasing of level of each fatty acid is less expressed. The effect of insulin reflects decreasing of content of double bonds in blood plasma. The number of double bonds characterizes the degree of unsaturation of fatty acids in lipids of blood plasma. The higher number of double bonds is in the pool of unesterified fatty acids the more active is the effect of insulin. The hyper-secretion of insulin is directly proportional to content of palmitic fatty acid in lipids of blood plasma on fasting. According the phylogenetic theory of general pathology, the effect of insulin on metabolism of glucose is mediated by fatty acids. The insulin is blocking lipolysis in insulin-depended subcutaneous adipocytes and decreases content of unesterified fatty acids in blood plasma. The insulin is depriving all cells of possibility to absorb unesterified fatty acids and "forces" them to absorb glucose increasing hereby number of GLUT4 on cell membrane. The resistance to insulin is manifested in high concentration of unesterfied fatty acids, hyperinsulinemia, hyperalbuminemia and increasing of concentration of C-reactive protein-monomer. The resistance to insulin is groundlessly referred to as a symptom of diabetes mellitus type II. The resistance to insulin is only a functional disorder lasting for years. It can be successfully arrested. The diabetes mellitus is developed against the background of resistance to insulin only after long-term hyper-secretion of insulin and under emaciation and death of β-cells. The diabetes mellitus type I and not type II is an undesirable outcome of resistance to insulin. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids, Unsaturated; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Male | 2014 |
Immune therapy and β-cell death in type 1 diabetes.
Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing β-cells. The killing of β-cells is not currently measurable; β-cell functional studies routinely used are affected by environmental factors such as glucose and cannot distinguish death from dysfunction. Moreover, it is not known whether immune therapies affect killing. We developed an assay to identify β-cell death by measuring relative levels of unmethylated INS DNA in serum and used it to measure β-cell death in a clinical trial of teplizumab. We studied 43 patients with recent-onset T1D, 13 nondiabetic subjects, and 37 patients with T1D treated with FcR nonbinding anti-CD3 monoclonal antibody (teplizumab) or placebo. Patients with recent-onset T1D had higher rates of β-cell death versus nondiabetic control subjects, but patients with long-standing T1D had lower levels. When patients with recent-onset T1D were treated with teplizumab, β-cell function was preserved (P < 0.05) and the rates of β-cell were reduced significantly (P < 0.05). We conclude that there are higher rates of β-cell death in patients with recent-onset T1D compared with nondiabetic subjects. Improvement in C-peptide responses with immune intervention is associated with decreased β-cell death. Topics: Adult; Antibodies, Monoclonal, Humanized; C-Peptide; CD3 Complex; Cytotoxicity Tests, Immunologic; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; DNA Methylation; Female; Humans; Hypoglycemic Agents; Immunologic Factors; Immunotherapy; Insulin; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans; Male; Postprandial Period; Young Adult | 2013 |
Interleukin-1 antagonism in type 1 diabetes of recent onset: two multicentre, randomised, double-blind, placebo-controlled trials.
Innate immunity contributes to the pathogenesis of autoimmune diseases, such as type 1 diabetes, but until now no randomised, controlled trials of blockade of the key innate immune mediator interleukin-1 have been done. We aimed to assess whether canakinumab, a human monoclonal anti-interleukin-1 antibody, or anakinra, a human interleukin-1 receptor antagonist, improved β-cell function in recent-onset type 1 diabetes.. We did two randomised, placebo-controlled trials in two groups of patients with recent-onset type 1 diabetes and mixed-meal-tolerance-test-stimulated C peptide of at least 0·2 nM. Patients in the canakinumab trial were aged 6-45 years and those in the anakinra trial were aged 18-35 years. Patients in the canakinumab trial were enrolled at 12 sites in the USA and Canada and those in the anakinra trial were enrolled at 14 sites across Europe. Participants were randomly assigned by computer-generated blocked randomisation to subcutaneous injection of either 2 mg/kg (maximum 300 mg) canakinumab or placebo monthly for 12 months or 100 mg anakinra or placebo daily for 9 months. Participants and carers were masked to treatment assignment. The primary endpoint was baseline-adjusted 2-h area under curve C-peptide response to the mixed meal tolerance test at 12 months (canakinumab trial) and 9 months (anakinra trial). Analyses were by intention to treat. These studies are registered with ClinicalTrials.gov, numbers NCT00947427 and NCT00711503, and EudraCT number 2007-007146-34.. Patients were enrolled in the canakinumab trial between Nov 12, 2010, and April 11, 2011, and in the anakinra trial between Jan 26, 2009, and May 25, 2011. 69 patients were randomly assigned to canakinumab (n=47) or placebo (n=22) monthly for 12 months and 69 were randomly assigned to anakinra (n=35) or placebo (n=34) daily for 9 months. No interim analyses were done. 45 canakinumab-treated and 21 placebo-treated patients in the canakinumab trial and 25 anakinra-treated and 26 placebo-treated patients in the anakinra trial were included in the primary analyses. The difference in C peptide area under curve between the canakinumab and placebo groups at 12 months was 0·01 nmol/L (95% CI -0·11 to 0·14; p=0·86), and between the anakinra and the placebo groups at 9 months was 0·02 nmol/L (-0·09 to 0·15; p=0·71). The number and severity of adverse events did not differ between groups in the canakinumab trial. In the anakinra trial, patients in the anakinra group had significantly higher grades of adverse events than the placebo group (p=0·018), which was mainly because of a higher number of injection site reactions in the anakinra group.. Canakinumab and anakinra were safe but were not effective as single immunomodulatory drugs in recent-onset type 1 diabetes. Interleukin-1 blockade might be more effective in combination with treatments that target adaptive immunity in organ-specific autoimmune disorders.. National Institutes of Health and Juvenile Diabetes Research Foundation. Topics: Adolescent; Adult; Analysis of Variance; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Humans; Hypoglycemic Agents; Immunologic Factors; Insulin-Secreting Cells; Interleukin 1 Receptor Antagonist Protein; Interleukin-1; Male; Treatment Outcome; Young Adult | 2013 |
Autologous umbilical cord blood infusion followed by oral docosahexaenoic acid and vitamin D supplementation for C-peptide preservation in children with Type 1 diabetes.
We sought to determine if autologous umbilical cord blood (UCB) infusion followed by 1 year of supplementation with vitamin D and docosahexaenoic acid (DHA) can preserve C-peptide in children with type 1 diabetes. We conducted an open-label, 2:1 randomized study in which 15 type 1 diabetes subjects with stimulated C-peptide > .2 pmol/mL received either (1) autologous UCB infusion, 1 year of daily oral vitamin D (2000 IU), and DHA (38 mg/kg) and intensive diabetes management or (2) intensive diabetes management alone. Primary analyses were performed 1 year after UCB infusion. Treated (N = 10) and control (N = 5) subjects had median ages of 7.2 and 6.6 years, respectively. No severe adverse events were observed. Although the absolute rate of C-peptide decline was slower in treated versus control subjects, intergroup comparisons failed to reach significance (P = .29). Area under the curve C-peptide declined and insulin use increased in both groups (P < .01). Vitamin D levels remained stable in treated subjects but declined in control subjects (P = .01). DHA levels rose in treated subjects versus control subjects (P = .003). CD4/CD8 ratio remained stable in treated subjects but declined in control subjects (P = .03). No changes were seen in regulatory T cell frequency, total CD4 counts, or autoantibody titers. Autologous UCB infusion followed by daily supplementation with vitamin D and DHA was safe but failed to preserve C-peptide. Lack of significance may reflect small sample size. Future efforts will require expansion of specific immunoregulatory cell subsets, optimization of combined immunoregulatory and anti-inflammatory agents, and larger study cohorts. Topics: Administration, Oral; Area Under Curve; C-Peptide; Case-Control Studies; CD4 Lymphocyte Count; Child; Child, Preschool; Cord Blood Stem Cell Transplantation; Diabetes Mellitus, Type 1; Docosahexaenoic Acids; Female; Humans; Infant; Infusions, Intravenous; Male; T-Lymphocyte Subsets; Transplantation, Autologous; Vitamin D | 2013 |
Sustained function of alginate-encapsulated human islet cell implants in the peritoneal cavity of mice leading to a pilot study in a type 1 diabetic patient.
Alginate-encapsulated human islet cell grafts have not been able to correct diabetes in humans, whereas free grafts have. This study examined in immunodeficient mice whether alginate-encapsulated graft function was inferior to that of free grafts of the same size and composition.. Cultured human islet cells were equally distributed over free and alginate-encapsulated grafts before implantation in, respectively, the kidney capsule and the peritoneal cavity of non-obese diabetic mice with severe combined immunodeficiency and alloxan-induced diabetes. Implants were followed for in vivo function and retrieved for analysis of cellular composition (all) and insulin secretory responsiveness (capsules).. Free implants with low beta cell purity (19 ± 1%) were non-functional and underwent 90% beta cell loss. At medium purity (50 ± 1%), they were functional at post-transplant week 1, evolving to normoglycaemia (4/8) or to C-peptide negativity (4/8) depending on the degree of beta cell-specific losses. Encapsulated implants immediately and sustainably corrected diabetes, irrespective of beta cell purity (16/16). Most capsules were retrievable as single units, enriched in endocrine cells that exhibited rapid secretory responses to glucose and glucagon. Single capsules with similar properties were also retrieved from a type 1 diabetic recipient at post-transplant month 3. However, the vast majority were clustered and contained debris, explaining the poor rise in plasma C-peptide.. In immunodeficient mice, i.p. implanted alginate-encapsulated human islet cells exhibited a better outcome than free implants under the kidney capsule. They did not show primary non-function at low beta cell purity and avoided beta cell-specific losses by rapidly establishing normoglycaemia. Retrieved capsules presented secretory responses to glucose, which was also observed in a type 1 diabetic recipient. Topics: Alginates; Animals; Blood Glucose; C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Female; Glucuronic Acid; Hexuronic Acids; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Middle Aged; Peritoneal Cavity | 2013 |
Exercise to preserve beta cell function in recent-onset type 1 diabetes mellitus (EXTOD)--a study protocol for a pilot randomized controlled trial.
Exercise has a beta cell preserving effect in patients with type 2 diabetes. This benefit of exercise has not been examined in type 1 diabetes. Significant beta cell function is present at the time of diagnosis of type 1 diabetes and therefore studies of beta cell preservation are ideally conducted immediately after diagnosis.Many of the variables required to design and power such a study are currently unknown. The aim of EXTOD is to obtain the information required to design a formal study of exercise and beta cell preservation in newly diagnosed patients with type 1 diabetes.. Barriers to exercise will initially be assessed in a qualitative study of newly diagnosed patients. Then, sixty newly diagnosed adult type 1 diabetes patients will be randomized to either conventional treatment or exercise, stratified on beta cell function and fitness. The exercise group will be encouraged to increase their level of activity to a minimum of 150 minutes of moderate to vigorous intensity exercise per week, aiming for 240 minutes per week of exercise for 12 months. Beta cell function will be measured by meal-stimulated C peptide. Primary outcomes are recruitment, adherence to exercise, loss to follow-up, and exercise levels in the non-intervention arm (contamination). The secondary outcome of the study is rate of loss of beta cell function.. The outcomes of the EXTOD study will help define the barriers, uptake and benefits of exercise in adults newly diagnosed with type 1 diabetes. This information will enable design of a formal study to assess the effect of exercise on beta cell preservation in newly diagnosed patients with type 1 diabetes.. Current controlled trials ISRCTN91388505. Topics: Biomarkers; C-Peptide; Clinical Protocols; Diabetes Mellitus, Type 1; Disease Progression; England; Exercise Therapy; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Motivation; Patient Compliance; Patient Selection; Physical Fitness; Pilot Projects; Postprandial Period; Research Design; Risk Reduction Behavior; Time Factors; Treatment Outcome | 2013 |
Teplizumab preserves C-peptide in recent-onset type 1 diabetes: two-year results from the randomized, placebo-controlled Protégé trial.
Protégé was a phase 3, randomized, double-blind, parallel, placebo-controlled 2-year study of three intravenous teplizumab dosing regimens, administered daily for 14 days at baseline and again after 26 weeks, in new-onset type 1 diabetes. We sought to determine efficacy and safety of teplizumab immunotherapy at 2 years and to identify characteristics associated with therapeutic response. Of 516 randomized patients, 513 were treated, and 462 completed 2 years of follow-up. Teplizumab (14-day full-dose) reduced the loss of C-peptide mean area under the curve (AUC), a prespecified secondary end point, at 2 years versus placebo. In analyses of prespecified and post hoc subsets at entry, U.S. residents, patients with C-peptide mean AUC >0.2 nmol/L, those randomized ≤6 weeks after diagnosis, HbA1c <7.5% (58 mmol/mol), insulin use <0.4 units/kg/day, and 8-17 years of age each had greater teplizumab-associated C-peptide preservation than their counterparts. Exogenous insulin needs tended to be reduced versus placebo. Antidrug antibodies developed in some patients, without apparent change in drug efficacy. No new safety or tolerability issues were observed during year 2. In summary, anti-CD3 therapy reduced C-peptide loss 2 years after diagnosis using a tolerable dose. Topics: Adolescent; Antibodies, Monoclonal, Humanized; Area Under Curve; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Administration Schedule; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunotherapy; Insulin; Placebos | 2013 |
Plasmid-encoded proinsulin preserves C-peptide while specifically reducing proinsulin-specific CD8⁺ T cells in type 1 diabetes.
In type 1 diabetes (T1D), there is an intense inflammatory response that destroys the β cells in the pancreatic islets of Langerhans, the site where insulin is produced and released. A therapy for T1D that targets the specific autoimmune response in this disease while leaving the remainder of the immune system intact, has long been sought. Proinsulin is a major target of the adaptive immune response in T1D. We hypothesized that an engineered DNA plasmid encoding proinsulin (BHT-3021) would preserve β cell function in T1D patients through reduction of insulin-specific CD8⁺ T cells. We studied 80 subjects over 18 years of age who were diagnosed with T1D within the past 5 years. Subjects were randomized 2:1 to receive intramuscular injections of BHT-3021 or BHT-placebo, weekly for 12 weeks, and then monitored for safety and immune responses in a blinded fashion. Four dose levels of BHT-3021 were evaluated: 0.3, 1.0, 3.0, and 6.0 mg. C-peptide was used both as an exploratory efficacy measure and as a safety measure. Islet-specific CD8⁺ T cell frequencies were assessed with multimers of monomeric human leukocyte antigen class I molecules loaded with peptides from pancreatic and unrelated antigens. No serious adverse events related to BHT-3021 were observed. C-peptide levels improved relative to placebo at all doses, at 1 mg at the 15-week time point (+19.5% BHT-3021 versus -8.8% BHT-placebo, P < 0.026). Proinsulin-reactive CD8⁺ T cells, but not T cells against unrelated islet or foreign molecules, declined in the BHT-3021 arm (P < 0.006). No significant changes were noted in interferon-γ, interleukin-4 (IL-4), or IL-10 production in CD4 T cells. Thus, we demonstrate that a plasmid encoding proinsulin reduces the frequency of CD8⁺ T cells reactive to proinsulin while preserving C-peptide over the course of dosing. Topics: Adult; C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Plasmids; Proinsulin | 2013 |
Teplizumab (anti-CD3 mAb) treatment preserves C-peptide responses in patients with new-onset type 1 diabetes in a randomized controlled trial: metabolic and immunologic features at baseline identify a subgroup of responders.
Trials of immune therapies in new-onset type 1 diabetes (T1D) have shown success, but not all subjects respond, and the duration of response is limited. Our aim was to determine whether two courses of teplizumab, an Fc receptor-nonbinding anti-CD3 monoclonal antibody, reduces the decline in C-peptide levels in patients with T1D 2 years after disease onset. We also set out to identify characteristics of responders. We treated 52 subjects with new-onset T1D with teplizumab for 2 weeks at diagnosis and after 1 year in an open-label, randomized, controlled trial. In the intent to treat analysis of the primary end point, patients treated with teplizumab had a reduced decline in C-peptide at 2 years (mean -0.28 nmol/L [95% CI -0.36 to -0.20]) versus control (mean -0.46 nmol/L [95% CI -0.57 to -0.35]; P = 0.002), a 75% improvement. The most common adverse events were rash, transient upper respiratory infections, headache, and nausea. In a post hoc analysis we characterized clinical responders and found that metabolic (HbA1c and insulin use) and immunologic features distinguished this group from those who did not respond to teplizumab. We conclude that teplizumab treatment preserves insulin production and reduces the use of exogenous insulin in some patients with new-onset T1D. Metabolic and immunologic features at baseline can identify a subgroup with robust responses to immune therapy. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Male | 2013 |
Early immunotherapy using autologous adult stem cells reversed the effect of anti-pancreatic islets in recently diagnosed type 1 diabetes mellitus: preliminary results.
Bone marrow stem cell treatment has been proven a promising therapeutic strategy and showed significant results given the strong immune modulating properties. We have investigated the safety and efficacy of autologous bone marrow stem cell transplantation through liver puncture in two patients with recently diagnosed type 1 diabetes mellitus.. The procedure was approved by the Institutional Ethics Committee. In 2011, in three young patients, type 1 diabetes mellitus diagnosis was confirmed, with the presence of positive antibodies and ketoacidosis. Two patients was treated with autologous bone marrow stem cell stimulated with filgrastim and transplantation, through liver puncture, as immune modulators. One patients was treated with conventional treatment and participate in this experiment as a control group. The families of the patients signed the informed consent. No specific statistical analysis was performed. The patients had less than 8 years old, diagnosis of type 1 diabetes for less than 60 days, body mass index less than 22 kg/m2, normal complete blood count, coagulation and renal function, no lesions in target organs, glycosylated hemoglobin (HbA1c) level less than 13.70%, c-peptide level less than 0.67 ng/ml, positive results of Islets Cells Antibody (ICA), Glutamic Acid Decarboxylase (GAD) and insulin antibody.. In two patients treated, the follow up at 12 months showed negative value in ICA, GAD and anti insulin antibody levels, with an increased levels of c peptide and decreased levels of blood glucose and HbA1c.. Treatment with autologous bone marrow stem cells is easy and effective as it reversed the production and effect of anti pancreatic islet antibody and significantly resulted in an increased c-peptide concentration. Topics: Adult Stem Cells; Blood Glucose; Bone Marrow Transplantation; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Filgrastim; Granulocyte Colony-Stimulating Factor; Hemoglobins; Humans; Immunotherapy; Insulin Antibodies; Islets of Langerhans; Recombinant Proteins; Transplantation, Autologous; Treatment Outcome | 2013 |
Effect of pioglitazone on the course of new-onset type 1 diabetes mellitus.
Type 1 diabetes mellitus (T1DM) is caused by insulin deficiency resulting from progressive destruction of β cells. The histological hallmark of the diabetic islet is mononuclear cell infiltration. Thiazolidinediones (TZDs) activate PPARg and enhance the actions of insulin. Studies in non-obese diabetic and streptocotozin-treated mouse models demonstrated that pretreatment with TZDs prevented the development of T1DM. The purpose of this study was to examine whether pioglitazone, given with insulin, preserved β cell function in patients with new-onset T1DM.. This was a randomized, double-blind, placebo-controlled 24-week study. Subjects received pioglitazone or placebo. Blood sugar, glycated hemoglobin (HbA1c), C-peptide, and liver enzymes were measured at baseline. Boost© stimulated C-peptide responses were measured at baseline and at 24 weeks. Blood sugar, insulin dose, height, weight, and liver enzymes were monitored at each visit. HbA1c was performed every 12 weeks.. Of the 15 patients, 8 received pioglitazone, and 7 - placebo. There was no clinical improvement in HbA1c between or within groups at the completion of the study. Mean peak C-peptide values were similar between groups at baseline. Mean peak C-peptide level was slightly higher at 24 weeks in the pioglitazone group compared to the placebo (1.8 vs. 1.5 ng/mL) which was considered as clinically insignificant. The interaction of HbA1c and insulin dose (HbA1c* insulin/kg/day), which combines degree of diabetic control and dose of insulin required to achieve this control, showed transient improvement in the pioglitazone group at 12 weeks but was not sustained at 24 weeks.. In this pilot study, pioglitazone did not preserve β cell function when compared to placebo. Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Pilot Projects; Pioglitazone; Prospective Studies; Thiazolidinediones; Time Factors; Treatment Outcome | 2013 |
Teplizumab treatment may improve C-peptide responses in participants with type 1 diabetes after the new-onset period: a randomised controlled trial.
Type 1 diabetes results from a chronic autoimmune process continuing for years after presentation. We tested whether treatment with teplizumab (a Fc receptor non-binding anti-CD3 monoclonal antibody), after the new-onset period, affects the decline in C-peptide production in individuals with type 1 diabetes.. In a randomised placebo-controlled trial we treated 58 participants with type 1 diabetes for 4-12 months with teplizumab or placebo at four academic centres in the USA. A central randomisation centre used computer generated tables to allocate treatments. Investigators, patients, and caregivers were blinded to group assignment. The primary outcome was a comparison of C-peptide responses to a mixed meal after 1 year. We explored modification of treatment effects in subgroups of patients.. Thirty-four and 29 subjects were randomized to the drug and placebo treated groups, respectively. Thirty-one and 27, respectively, were analysed. Although the primary outcome analysis showed a 21.7% higher C-peptide response in the teplizumab-treated group (0.45 vs 0.371; difference, 0.059 [95% CI 0.006, 0.115] nmol/l) (p = 0.03), when corrected for baseline imbalances in HbA(1c) levels, the C-peptide levels in the teplizumab-treated group were 17.7% higher (0.44 vs 0.378; difference, 0.049 [95% CI 0, 0.108] nmol/l, p = 0.09). A greater proportion of placebo-treated participants lost detectable C-peptide responses at 12 months (p = 0.03). The teplizumab group required less exogenous insulin (p < 0.001) but treatment differences in HbA(1c) levels were not observed. Teplizumab was well tolerated. A subgroup analysis showed that treatment benefits were larger in younger individuals and those with HbA(1c) <6.5% at entry. Clinical responders to teplizumab had an increase in circulating CD8 central memory cells 2 months after enrolment compared with non-responders.. This study suggests that deterioration in insulin secretion may be affected by immune therapy with teplizumab after the new-onset period but the magnitude of the effect is less than during the new-onset period. Our studies identify characteristics of patients most likely to respond to this immune therapy.. ClinicalTrials.gov NCT00378508. This work was supported by grants 2007-502, 2007-1059 and 2006-351 from the JDRF and grants R01 DK057846, P30 DK20495, UL1 RR024139, UL1RR025780, UL1 RR024131 and UL1 RR024134 from the NIH. Topics: Adolescent; Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male | 2013 |
Long term effects of the implantation of Wharton's jelly-derived mesenchymal stem cells from the umbilical cord for newly-onset type 1 diabetes mellitus.
Type 1 diabetes mellitus (T1DM) is an autoimmune disorder resulted from T cell-mediated destruction of pancreatic β-cells, how to regenerate β-cells and prevent the autoimmune destruction of remnant and neogenetic β-cells is a tough problem. Immunomodulatory propertity of mesenchymal stem cell make it illuminated to overcome it. We assessed the long-term effects of the implantation of Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) from the umbilical cord for Newly-onset T1DM. Twenty-nine patients with newly onset T1DM were randomly divided into two groups, patients in group I were treated with WJ-MSCs and patients in group II were treated with normal saline based on insulin intensive therapy. Patients were followed-up after the operation at monthly intervals for the first 3 months and thereafter every 3 months for the next 21 months, the occurrence of any side effects and results of laboratory examinations were evaluated. There were no reported acute or chronic side effects in group I compared with group II, both the HbA1c and C peptide in group I patients were significantly better than either pretherapy values or group II patients during the follow-up period. These data suggested that the implantation of WJ-MSCs for the treatment of newly-onset T1DM is safe and effective. This therapy can restore the function of islet β cells in a longer time, although precise mechanisms are unknown, the implantation of WJ-MSCs is expected to be an effective strategy for treatment of type1 diabetes. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Fasting; Female; Glycated Hemoglobin; Humans; Insulin; Insulin-Secreting Cells; Male; Mesenchymal Stem Cell Transplantation; Postprandial Period; Umbilical Cord; Wharton Jelly; Young Adult | 2013 |
Enhanced absorption of insulin aspart as the result of a dispersed injection strategy tested in a randomized trial in type 1 diabetic patients.
We investigated the impact of two different injection strategies on the pharmacokinetics and pharmacodynamics of insulin aspart in vivo in an open-label, two-period crossover study and verified changes in the surface-to-volume ratio ex vivo.. Before the clinical trial, insulin aspart was injected ex vivo into explanted human abdominal skin flaps. The surface-to-volume ratio of the subcutaneous insulin depot was assessed by microfocus computed tomography that compared 1 bolus of 18 IU with 9 dispersed boluses of 2 IU. These two injection strategies were then tested in vivo, in 12 C-peptide-negative type 1 diabetic patients in a euglycemic glucose clamp (glucose target 5.5 ± 1.1 mmol/L) for 8 h after the first insulin administration.. The ex vivo experiment showed a 1.8-fold higher mean surface-to-volume ratio for the dispersed injection strategy. The maximum glucose infusion rates (GIR) were similar for the two strategies (10 ± 4 vs. 9 ± 4; P = 0.5); however, times to reach maximum GIR and 50% and 10% of the maximum GIR were significantly reduced by using the 9 × 2 IU strategy (68 ± 33 vs. 127 ± 93 min; P = 0.01; 38 ± 9 vs. 49 ± 16 min; P < 0.01; 23 ± 6 vs. 30 ± 10 min; P < 0.05). For 9 × 2 IU, the area under the GIR curve was greater during the first 60 min (219 ± 89 vs. 137 ± 75; P < 0.01) and halved until maximum GIR (242 ± 183 vs. 501 ± 396; P < 0.01); however, it was similar across the whole study period (1,361 ± 469 vs. 1,565 ± 527; P = 0.08).. A dispersed insulin injection strategy enhanced the effect of a fast-acting insulin analog. The increased surface-to-volume ratio of the subcutaneous insulin depot can facilitate insulin absorption into the vascular system. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin Aspart; Male; Young Adult | 2013 |
Metabolic effects of honey in type 1 diabetes mellitus: a randomized crossover pilot study.
The aim of this study was to evaluate the metabolic effects of 12-week honey consumption on patients suffering from type 1 diabetes mellitus (DM). This was a randomized crossover clinical trial done in the National Institute for Diabetes and Endocrinology, Cairo, Egypt. Twenty patients of both sexes aged 4-18 years with type 1 DM and HbA1C<10% participated in the study. They were randomized into two equal groups (intervention to control and control to intervention). The dietary intervention was 12-week honey consumption in a dose of 0.5 mL/kg body weight per day. The main outcome measures were serum glucose, lipids, and C-peptide, and anthropometric measurements. None of participants were lost in follow-up. The intervention resulted in significant decreases in subscapular skin fold thickness (SSFT; P=.002), fasting serum glucose (FSG; P=.001), total cholesterol (P=.0001), serum triglycerides (TG; P=.0001), and low-density lipoprotein (P=.0009), and significant increases in fasting C-peptide (FCP; P=.0004) and 2-h postprandial C-peptide (PCP; P=.002). As possible long-term effects of honey after its withdrawal, statistically significant reductions in midarm circumference (P=.000), triceps skin fold thickness (P=.006), SSFT (P=.003), FSG (P=.005), 2-h postprandial serum glucose (P=.000), TG (P=.003), and HbA1C (P=.043), and significant increases in FCP (P=.002) and PCP (P=.003) were observed. This small clinical trial suggests that long-term consumption of honey might have positive effects on the metabolic derangements of type 1 DM. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Cross-Over Studies; Diabetes Mellitus, Type 1; Female; Honey; Humans; Hypoglycemic Agents; Insulin; Male; Pilot Projects; Triglycerides | 2013 |
A randomized placebo-controlled trial of alphacalcidol on the preservation of beta cell function in children with recent onset type 1 diabetes.
This participant-blinded parallel-group randomized placebo-controlled study demonstrated that alfacalcidol (vitamin D analogue) preserves beta cell function in newly diagnosed type 1 diabetes (T1DM) in children.. Subjects from outpatient clinic were randomized to intervention and control groups. Inclusion: (1) age 8-15, (2) T1DM, (3) duration <8 weeks, (4) no chronic diseases, (5) stable diet. Exclusion: (1) vitamin D, calcium supplements or fortified foods, (2) hypercalcemia. Intervention group received alfacalcidol 0.25 μg twice daily, while control group received placebo. Insulin given physician-titrated to blood glucose. Safety monitored by serum calcium and phosphate. Beta cell function assessed at 0, 3, 6 months using fasting C-peptide (FCP) and daily insulin dosage per body weight (DID). Primary outcome measured using multivariate repeated measures GLM-ANOVA, with FCP and DID as primary measures and age, gender, sunlight exposure, 25-hydroxy vitamin D, and HbA1c as covariates.. Of 61 subjects, 7 dropped out. GLM-ANOVA showed that groups were different (p=0.019, Eta-squared=0.087), with no significant covariates. FCP was higher and DID lower in the intervention group, with males having stronger responses to alfacalcidol (p=0.001). No adverse effects were observed.. The study confirmed that alfacalcidol can safely preserve beta cell function in newly diagnosed T1DM in children, with a stronger effect in males.. IRCT201205159753N1. Topics: Adolescent; Blood Glucose; Body Weight; C-Peptide; Calcium, Dietary; Child; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Humans; Hydroxycholecalciferols; Hypercalcemia; Insulin; Insulin-Secreting Cells; Linear Models; Male; Multivariate Analysis; Single-Blind Method | 2013 |
Does the fat-protein meal increase postprandial glucose level in type 1 diabetes patients on insulin pump: the conclusion of a randomized study.
Our study examines the hypothesis that in addition to sugar starch-type diet, a fat-protein meal elevates postprandial glycemia as well, and it should be included in calculated prandial insulin dose accordingly. The goal was to determine the impact of the inclusion of fat-protein nutrients in the general algorithm for the mealtime insulin dose calculator on 6-h postprandial glycemia.. Of 26 screened type 1 diabetes patients using an insulin pump, 24 were randomly assigned to an experimental Group A and to a control Group B. Group A received dual-wave insulin boluses for their pizza dinner, consisting of 45 g/180 kcal of carbohydrates and 400 kcal from fat-protein where the insulin dose was calculated using the following algorithm: n Carbohydrate Units×ICR+n Fat-Protein Units×ICR/6 h (standard+extended insulin boluses), where ICR represents the insulin-to-carbohydrate ratio. For the control Group B, the algorithm used was n Carbohydrate Units×ICR. The glucose, C-peptide, and glucagon concentrations were evaluated before the meal and at 30, 60, 120, 240, and 360 min postprandial.. There were no statistically significant differences involving patients' metabolic control, C-peptide, glucagon secretion, or duration of diabetes between Group A and B. In Group A the significant glucose increment occurred at 120-360 min, with its maximum at 240 min: 60.2 versus -3.0 mg/dL (P=0.04), respectively. There were no significant differences in glucagon and C-peptide concentrations postprandial.. A mixed meal effectively elevates postprandial glycemia after 4-6 h. Dual-wave insulin bolus, in which insulin is calculated for both the carbohydrates and fat proteins, is effective in controlling postprandial glycemia. Topics: Adolescent; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Dietary Fats; Dietary Proteins; Female; Glucagon; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin Infusion Systems; Male; Postprandial Period | 2012 |
Reversal of type 1 diabetes via islet β cell regeneration following immune modulation by cord blood-derived multipotent stem cells.
Inability to control autoimmunity is the primary barrier to developing a cure for type 1 diabetes (T1D). Evidence that human cord blood-derived multipotent stem cells (CB-SCs) can control autoimmune responses by altering regulatory T cells (Tregs) and human islet β cell-specific T cell clones offers promise for a new approach to overcome the autoimmunity underlying T1D.. We developed a procedure for Stem Cell Educator therapy in which a patient's blood is circulated through a closed-loop system that separates lymphocytes from the whole blood and briefly co-cultures them with adherent CB-SCs before returning them to the patient's circulation. In an open-label, phase1/phase 2 study, patients (n=15) with T1D received one treatment with the Stem Cell Educator. Median age was 29 years (range: 15 to 41), and median diabetic history was 8 years (range: 1 to 21).. Stem Cell Educator therapy was well tolerated in all participants with minimal pain from two venipunctures and no adverse events. Stem Cell Educator therapy can markedly improve C-peptide levels, reduce the median glycated hemoglobin A1C (HbA1C) values, and decrease the median daily dose of insulin in patients with some residual β cell function (n=6) and patients with no residual pancreatic islet β cell function (n=6). Treatment also produced an increase in basal and glucose-stimulated C-peptide levels through 40 weeks. However, participants in the Control Group (n=3) did not exhibit significant change at any follow-up. Individuals who received Stem Cell Educator therapy exhibited increased expression of co-stimulating molecules (specifically, CD28 and ICOS), increases in the number of CD4+CD25+Foxp3+ Tregs, and restoration of Th1/Th2/Th3 cytokine balance.. Stem Cell Educator therapy is safe, and in individuals with moderate or severe T1D, a single treatment produces lasting improvement in metabolic control. Initial results indicate Stem Cell Educator therapy reverses autoimmunity and promotes regeneration of islet β cells. Successful immune modulation by CB-SCs and the resulting clinical improvement in patient status may have important implications for other autoimmune and inflammation-related diseases without the safety and ethical concerns associated with conventional stem cell-based approaches.. ClinicalTrials.gov number, NCT01350219. Topics: Adolescent; Adult; C-Peptide; Cell Communication; Cells, Cultured; Diabetes Mellitus, Type 1; Female; Fetal Blood; Follow-Up Studies; Humans; Immunomodulation; Insulin-Secreting Cells; Male; Multipotent Stem Cells; Recovery of Function; Regeneration; T-Lymphocyte Subsets; T-Lymphocytes, Regulatory | 2012 |
GAD65 antigen therapy in recently diagnosed type 1 diabetes mellitus.
The 65-kD isoform of glutamic acid decarboxylase (GAD65) is a major autoantigen in type 1 diabetes. We hypothesized that alum-formulated GAD65 (GAD-alum) can preserve beta-cell function in patients with recent-onset type 1 diabetes.. We studied 334 patients, 10 to 20 years of age, with type 1 diabetes, fasting C-peptide levels of more than 0.3 ng per milliliter (0.1 nmol per liter), and detectable serum GAD65 autoantibodies. Within 3 months after diagnosis, patients were randomly assigned to receive one of three study treatments: four doses of GAD-alum, two doses of GAD-alum followed by two doses of placebo, or four doses of placebo. The primary outcome was the change in the stimulated serum C-peptide level (after a mixed-meal tolerance test) between the baseline visit and the 15-month visit. Secondary outcomes included the glycated hemoglobin level, mean daily insulin dose, rate of hypoglycemia, and fasting and maximum stimulated C-peptide levels.. The stimulated C-peptide level declined to a similar degree in all study groups, and the primary outcome at 15 months did not differ significantly between the combined active-drug groups and the placebo group (P=0.10). The use of GAD-alum as compared with placebo did not affect the insulin dose, glycated hemoglobin level, or hypoglycemia rate. Adverse events were infrequent and mild in the three groups, with no significant differences.. Treatment with GAD-alum did not significantly reduce the loss of stimulated C peptide or improve clinical outcomes over a 15-month period. (Funded by Diamyd Medical and the Swedish Child Diabetes Foundation; ClinicalTrials.gov number, NCT00723411.). Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Male; Protein Isoforms; Young Adult | 2012 |
Effects of diet soda on gut hormones in youths with diabetes.
In patients with type 2 diabetes, but not type 1 diabetes, abnormal secretion of incretins in response to oral nutrients has been described. In healthy youths, we recently reported accentuated glucagon-like peptide 1 (GLP-1) secretion in response to a diet soda sweetened with sucralose and acesulfame-K. In this study, we examined the effect of diet soda on gut hormones in youths with diabetes.. Subjects aged 12-25 years with type 1 diabetes (n = 9) or type 2 diabetes (n = 10), or healthy control participants (n = 25) drank 240 mL cola-flavored caffeine-free diet soda or carbonated water, followed by a 75-g glucose load, in a randomized, cross-over design. Glucose, C-peptide, GLP-1, glucose-dependent insulinotropic peptide (GIP), and peptide Tyr-Tyr (PYY) were measured for 180 min. Glucose and GLP-1 have previously been reported for the healthy control subjects.. GLP-1 area under the curve (AUC) was 43% higher after ingestion of diet soda versus carbonated water in individuals with type 1 diabetes (P = 0.020), similar to control subjects (34% higher, P = 0.029), but was unaffected by diet soda in patients with type 2 diabetes (P = 0.92). Glucose, C-peptide, GIP, and PYY AUC were not statistically different between the two conditions in any group.. Ingestion of diet soda before a glucose load augmented GLP-1 secretion in type 1 diabetic and control subjects but not type 2 diabetic subjects. GIP and PYY secretion were not affected by diet soda. The clinical significance of this increased GLP-1 secretion, and its absence in youths with type 2 diabetes, needs to be determined. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Carbonated Beverages; Child; Cross-Over Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Glucagon-Like Peptide 1; Glucose; Humans; Male; Peptide YY; Young Adult | 2012 |
Improved preservation of residual beta cell function by atorvastatin in patients with recent onset type 1 diabetes and high CRP levels (DIATOR trial).
A recent randomized placebo-controlled trial of the effect of atorvastatin treatment on the progression of newly diagnosed type 1 diabetes suggested a slower decline of residual beta cell function with statin treatment. Aim of this secondary analysis was to identify patient subgroups which differ in the decline of beta cell function during treatment with atorvastatin.. The randomized placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and detectable islet autoantibodies (mean age 30 years, 40% females), in 12 centers in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. For this secondary analysis patients were stratified by single baseline characteristics which were considered to possibly be modified by atorvastatin treatment. Subgroups defined by age, sex or by baseline metabolic parameters like body mass index (BMI), total serum cholesterol or fasting C-peptide did not differ in C-peptide outcome after atorvastatin treatment. However, the subgroup defined by high (above median) baseline C-reactive protein (CRP) concentrations exhibited higher stimulated C-peptide secretion after statin treatment (p = 0.044). Individual baseline CRP levels correlated with C-peptide outcome in the statin group (r(2) = 0.3079, p<0.004). The subgroup with baseline CRP concentrations above median differed from the corresponding subgroup with lower CRP levels by higher median values of BMI, IL-6, IL-1RA, sICAM-1 and E-selectin.. Atorvastatin treatment may be effective in slowing the decline of beta cell function in a patient subgroup defined by above median levels of CRP and other inflammation associated immune mediators.. ClinicalTrials.gov NCT00974740. Topics: Adolescent; Adult; Age of Onset; Atorvastatin; C-Peptide; C-Reactive Protein; Diabetes Mellitus, Type 1; Female; Germany; Heptanoic Acids; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Insulin; Insulin-Secreting Cells; Male; Pyrroles; Young Adult | 2012 |
Sensor augmented pump therapy from onset of type 1 diabetes: late follow-up results of the Pediatric Onset Study.
To evaluate the metabolic control and β-cell function 1 yr after the end of the European multicentre randomized Pediatric Onset Study.. Of 154 study patients, 131 were re-examined 24 months after type 1 diabetes onset (49.6% boys, age at onset 8.9 ± 4.3 yrs). Of which, 62 patients belonged to the primary group of the main study applying a sensor-augmented pump system during the first yr and 69 patients to the control group performing conventional insulin pump therapy with self-monitoring blood glucose. HbA1c, fasting blood glucose, and C-peptide were centrally measured (Clinical Trail Registration Number: ISRCTN05450731).. At 24 months, i.e., 1 yr after the end of the interventional study, 52.4% of the patients used the sensor-augmented pump system, 46.0% conventional pump, and 1.6% multiple daily injections. HbA1c was 7.6 ± 1.3% in the primary and 7.7 ± 1.2% in the control group (p = 0.493). Frequent sensor use during the first yr was associated with statistically insignificant lowering of the HbA1c at 24 months (p = 0.236) as compared with irregular or no sensor use (7.4 ± 1.0% vs. 7.7 ± 1.3%). Although fasting C-peptide was not clearly different between the primary and control group (0.13 ± 0.17 vs. 0.09 ± 0.10 nmol/L, p = 0.121), patients with frequent sensor use had significantly less C-peptide loss within 24 months (C-peptide reduction 0.02 ± 0.18 vs. 0.07 ± 0.11 nmol/L, p = 0.046). There was no difference between the groups regarding daily insulin requirements.. Sensor-augmented pump therapy from onset of diabetes may lead to better long-term glycemic control and help to preserve endogenous β-cell function, if patients comply with frequent use of continuous glucose monitoring. Topics: Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Infant; Insulin; Insulin Infusion Systems; Male | 2012 |
Diabetic ketoacidosis at diagnosis influences complete remission after treatment with hematopoietic stem cell transplantation in adolescents with type 1 diabetes.
To determine if autologous nonmyeloablative hematopoietic stem cell transplantation (AHSCT) was beneficial for type 1 diabetic adolescents with diabetic ketoacidosis (DKA) at diagnosis.. We enrolled 28 patients with type 1 diabetes, aged 14-30 years, in a prospective AHSCT phase II clinical trial. HSCs were harvested from the peripheral blood after pretreatment consisting of a combination of cyclophosphamide and antithymocyte globulin. Changes in the exogenous insulin requirement were observed and serum levels of HbA(1c), C-peptide, and anti-glutamic acid decarboxylase antibody were measured before and after the AHSCT.. After transplantation, complete remission (CR), defined as insulin independence, was observed in 15 of 28 patients (53.6%) over a mean period of 19.3 months during a follow-up ranging from 4 to 42 months. The non-DKA patients achieved a greater CR rate than the DKA patients (70.6% in non-DKA vs. 27.3% in DKA, P = 0.051). In the non-DKA group, the levels of fasting C-peptide, peak value during oral glucose tolerance test (C(max)), and area under C-peptide release curve during oral glucose tolerance test were enhanced significantly 1 month after transplantation and remained high during the 24-month follow-up (all P < 0.05). In the DKA group, significant elevation of fasting C-peptide levels and C(max) levels was observed only at 18 and 6 months, respectively. There was no mortality.. We have performed AHSCT in 28 patients with type 1 diabetes. The data show AHSCT to be an effective long-term treatment for insulin dependence that achieved a greater efficacy in patients without DKA at diagnosis. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glucose Tolerance Test; Glutamate Decarboxylase; Hematopoietic Stem Cell Transplantation; Humans; Insulin; Male; Prospective Studies; Remission Induction; Transplantation, Autologous | 2012 |
Improvement in outcomes of clinical islet transplantation: 1999-2010.
To describe trends of primary efficacy and safety outcomes of islet transplantation in type 1 diabetes recipients with severe hypoglycemia from the Collaborative Islet Transplant Registry (CITR) from 1999 to 2010.. A total of 677 islet transplant-alone or islet-after-kidney recipients with type 1 diabetes in the CITR were analyzed for five primary efficacy outcomes and overall safety to identify any differences by early (1999-2002), mid (2003-2006), or recent (2007-2010) transplant era based on annual follow-up to 5 years.. Insulin independence at 3 years after transplant improved from 27% in the early era (1999-2002, n = 214) to 37% in the mid (2003-2006, n = 255) and to 44% in the most recent era (2007-2010, n = 208; P = 0.006 for years-by-era; P = 0.01 for era alone). C-peptide ≥0.3 ng/mL, indicative of islet graft function, was retained longer in the most recent era (P < 0.001). Reduction of HbA(1c) and resolution of severe hypoglycemia exhibited enduring long-term effects. Fasting blood glucose stabilization also showed improvements in the most recent era. There were also modest reductions in the occurrence of adverse events. The islet reinfusion rate was lower: 48% by 1 year in 2007-2010 vs. 60-65% in 1999-2006 (P < 0.01). Recipients that ever achieved insulin-independence experienced longer duration of islet graft function (P < 0.001).. The CITR shows improvement in primary efficacy and safety outcomes of islet transplantation in recipients who received transplants in 2007-2010 compared with those in 1999-2006, with fewer islet infusions and adverse events per recipient. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Islets of Langerhans Transplantation; Middle Aged; Registries; Treatment Outcome | 2012 |
Effect of cholecalciferol as adjunctive therapy with insulin on protective immunologic profile and decline of residual β-cell function in new-onset type 1 diabetes mellitus.
To evaluate the effect of vitamin D3 on cytokine levels, regulatory T cells, and residual β-cell function decline when cholecalciferol (vitamin D3 administered therapeutically) is given as adjunctive therapy with insulin in new-onset type 1 diabetes mellitus (T1DM).. An 18-month (March 10, 2006, to October 28, 2010) randomized, double-blind, placebo-controlled trial was conducted at the Diabetes Center of São Paulo Federal University, São Paulo, Brazil.. Thirty-eight patients with new-onset T1DM with fasting serum C-peptide levels greater than or equal to 0.6 ng/mL were randomly assigned to receive daily oral therapy of cholecalciferol, 2000 IU, or placebo.. Levels of proinflammatory and anti-inflammatory cytokines, chemokines, regulatory T cells, hemoglobin A1c, and C-peptide; body mass index; and insulin daily dose.. Mean (SD) chemokine ligand 2 (monocyte chemoattractant protein 1) levels were significantly higher (184.6 [101.1] vs 121.4 [55.8] pg/mL) at 12 months, as well as the increase in regulatory T-cell percentage (4.55% [1.5%] vs 3.34% [1.8%]) with cholecalciferol vs placebo. The cumulative incidence of progression to undetectable (≤0.1 ng/mL) fasting C-peptide reached 18.7% in the cholecalciferol group and 62.5% in the placebo group; stimulated C-peptide reached 6.2% in the cholecalciferol group and 37.5% in the placebo group at 18 months. Body mass index, hemoglobin A1c level, and insulin requirements were similar between the 2 groups.. Cholecalciferol used as adjunctive therapy with insulin is safe and associated with a protective immunologic effect and slow decline of residual β-cell function in patients with new-onset T1DM. Cholecalciferol may be an interesting adjuvant in T1DM prevention trials. Topics: Adolescent; Age of Onset; B-Lymphocytes; Body Mass Index; Brazil; C-Peptide; Child; Cholecalciferol; Cytokines; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Hypoglycemic Agents; Immunity, Cellular; Insulin; Male; Prevalence; Prospective Studies; Treatment Outcome; Vitamins | 2012 |
Proof-of-concept, randomized, controlled clinical trial of Bacillus-Calmette-Guerin for treatment of long-term type 1 diabetes.
No targeted immunotherapies reverse type 1 diabetes in humans. However, in a rodent model of type 1 diabetes, Bacillus Calmette-Guerin (BCG) reverses disease by restoring insulin secretion. Specifically, it stimulates innate immunity by inducing the host to produce tumor necrosis factor (TNF), which, in turn, kills disease-causing autoimmune cells and restores pancreatic beta-cell function through regeneration.. Translating these findings to humans, we administered BCG, a generic vaccine, in a proof-of-principle, double-blind, placebo-controlled trial of adults with long-term type 1 diabetes (mean: 15.3 years) at one clinical center in North America. Six subjects were randomly assigned to BCG or placebo and compared to self, healthy paired controls (n = 6) or reference subjects with (n = 57) or without (n = 16) type 1 diabetes, depending upon the outcome measure. We monitored weekly blood samples for 20 weeks for insulin-autoreactive T cells, regulatory T cells (Tregs), glutamic acid decarboxylase (GAD) and other autoantibodies, and C-peptide, a marker of insulin secretion. BCG-treated patients and one placebo-treated patient who, after enrollment, unexpectedly developed acute Epstein-Barr virus infection, a known TNF inducer, exclusively showed increases in dead insulin-autoreactive T cells and induction of Tregs. C-peptide levels (pmol/L) significantly rose transiently in two BCG-treated subjects (means: 3.49 pmol/L [95% CI 2.95-3.8], 2.57 [95% CI 1.65-3.49]) and the EBV-infected subject (3.16 [95% CI 2.54-3.69]) vs.1.65 [95% CI 1.55-3.2] in reference diabetic subjects. BCG-treated subjects each had more than 50% of their C-peptide values above the 95(th) percentile of the reference subjects. The EBV-infected subject had 18% of C-peptide values above this level.. We conclude that BCG treatment or EBV infection transiently modified the autoimmunity that underlies type 1 diabetes by stimulating the host innate immune response. This suggests that BCG or other stimulators of host innate immunity may have value in the treatment of long-term diabetes.. ClinicalTrials.gov NCT00607230. Topics: Adult; Autoantibodies; Autoimmunity; BCG Vaccine; Biomarkers; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glutamate Decarboxylase; Herpesvirus 4, Human; Humans; Insulin-Secreting Cells; Male; Middle Aged; Placebos; T-Lymphocytes; Tumor Necrosis Factor-alpha | 2012 |
Continuous glucose monitoring after islet transplantation in type 1 diabetes: an excellent graft function (β-score greater than 7) Is required to abrogate hyperglycemia, whereas a minimal function is necessary to suppress severe hypoglycemia (β-score grea
For the last 10 yr, continuous glucose monitoring (CGM) has brought up new insights into the accuracy of blood glucose analysis.. Our objective was to determine how islet graft function was able to influence the various components of dysglycemia after islet transplantation (IT).. We conducted a single-arm open-labeled study with a 3-yr follow-up in a referral center (ClinicalTrial.gov identifiers NCT00446264 and NCT01123187).. Twenty-three consecutive patients with type 1 diabetes (14 islet alone, nine islet after kidney) received IT within 3 months using the Edmonton protocol.. INTERVENTION included 72-h CGM before and 3, 6, 9, 12, 24, and 36 months after transplantation.. Graft function was estimated via β-score, a previously validated index (range 0-8) based on treatment requirements, C-peptide, blood glucose, and glycated hemoglobin.. At the 3-yr visit, graft function persisted in 19 patients (82%), and 10 (43%) remained insulin independent. Glycated hemoglobin decreased in the whole cohort from 8.3% (7.3-9.0%) at baseline to 6.7% (5.9-7.7%) at 3 yr [median (interquartile range), P < 0.01]. Mean glucose, glucose sd, and time spent with glycemia above 10 mmol/liter (hyperglycemia) and below 3 mmol/liter (hypoglycemia) were significantly lower after IT (P < 0.05 vs. baseline). The four CGM outcomes were related to β-score (P < 0.001). However, partial function (β-score >3) was sufficient to abrogate hypoglycemia; suboptimal function (β-score >5) was necessary to significantly improve mean glucose, glucose sd, and hyperglycemia; and optimal function (β score >7) was necessary to normalize them.. The four components of dysglycemia were not equally affected by the degree of islet graft function, which could have important implications for future development of β-cell replacement. A β-score above 3 dramatically reduced the occurrence of hypoglycemia. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemia; Islets of Langerhans Transplantation; Male; Middle Aged; Treatment Outcome | 2012 |
The glycemic and peak incremental indices of honey, sucrose and glucose in patients with type 1 diabetes mellitus: effects on C-peptide level-a pilot study.
Our study was a case-control cross-sectional study that was conducted on 20 children and adolescents suffering from type 1 diabetes mellitus and ten healthy non-diabetic children and adolescents serving as controls. The mean age of patients was 10.95 years. Oral sugar tolerance tests using glucose, sucrose and honey and measurement of fasting and postprandial serum C-peptide levels were done for all subjects in three separate sittings. The glycemic index (GI) and the peak incremental index (PII) were then calculated for each subject. Honey, compared to sucrose, had lower GI and PII in both patients (P < 0.001) and control (P < 0.05) groups. In the patients group, the increase in the level of C-peptide after using honey was not significant when compared with using either glucose or sucrose. However, in the control group, honey produced a significant higher C-peptide level, when compared with either glucose or sucrose. In conclusion, honey, because of its lower GI and PII when compared with sucrose, may be used as a sugar substitute in patients with type 1 diabetes mellitus. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glucose; Glucose Tolerance Test; Glycemic Index; Honey; Humans; Infant; Male; Osmolar Concentration; Pilot Projects; Sucrose; Up-Regulation | 2011 |
Extended evaluation of the safety and efficacy of GAD treatment of children and adolescents with recent-onset type 1 diabetes: a randomised controlled trial.
The aim of this study was to investigate the safety and efficacy of alum formulated glutamic acid decarboxylase GAD(65) (GAD-alum) treatment of children and adolescents with type 1 diabetes after 4 years of follow-up.. Seventy children and adolescents aged 10-18 years with recent onset type 1 diabetes participated in a phase II, double-blind, randomised placebo-controlled clinical trial. Patients identified as possible participants attended one of eight clinics in Sweden to receive information about the study and for an eligibility check, including a medical history. Participants were randomised to one of the two treatment groups and received either a subcutaneous injection of 20 μg of GAD-alum or placebo at baseline and 1 month later. The study was blinded to participants and investigators until month 30. The study was unblinded at 15 months to the sponsor and statistician in order to evaluate the data. At follow-up after 30 months there was a significant preservation of residual insulin secretion, as measured by C-peptide, in the group receiving GAD-alum compared with placebo. This was particularly evident in patients with <6 months disease duration at baseline. There were no treatment-related serious adverse events. We have now followed these patients for 4 years. Overall, 59 patients, 29 who had been treated with GAD-alum and 30 who had received placebo, gave their informed consent.. One patient in each treatment group experienced an episode of keto-acidosis between months 30 and 48. There were no treatment-related adverse events. The primary efficacy endpoint was the change in fasting C-peptide concentration from baseline to 15 months after the prime injection for all participants per protocol set. In the GAD-alum group fasting C-peptide was 0.332 ± 0.032 nmol/l at day 1 and 0.215 ± 0.031 nmol/l at month 15. The corresponding figures for the placebo group were 0.354 ± 0.039 and 0.184 ± 0.033 nmol/l, respectively. The decline in fasting C-peptide levels between day 1 and month 1, was smaller in the GAD-alum group than the placebo group. The difference between the treatment groups was not statistically significant. In those patients who were treated within 6 months of diabetes diagnosis, fasting C-peptide had decreased significantly less in the GAD-alum group than in the placebo-treated group after 4 years.. Four years after treatment with GAD-alum, children and adolescents with recent-onset type 1 diabetes continue to show no adverse events and possibly to show clinically relevant preservation of C-peptide.. ClinicalTrials.gov NCT00435981. The study was funded by The Swedish Research Council K2008-55X-20652-01-3, Barndiabetesfonden (The Swedish Child Diabetes Foundation), the Research Council of Southeast Sweden, and an unrestricted grant from Diamyd Medical AB. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glutamate Decarboxylase; Humans; Male; Treatment Outcome | 2011 |
Urinary C-peptide creatinine ratio is a practical outpatient tool for identifying hepatocyte nuclear factor 1-{alpha}/hepatocyte nuclear factor 4-{alpha} maturity-onset diabetes of the young from long-duration type 1 diabetes.
Hepatocyte nuclear factor 1-α (HNF1A)/hepatocyte nuclear factor 4-α (HNF4A) maturity-onset diabetes of the young (MODY) is frequently misdiagnosed as type 1 diabetes, and patients are inappropriately treated with insulin. Blood C-peptide can aid in the diagnosis of MODY, but practical reasons limit its widespread use. Urinary C-peptide creatinine ratio (UCPCR), a stable measure of endogenous insulin secretion, is a noninvasive alternative. We aimed to compare stimulated UCPCR in adults with HNF1A/4A MODY, type 1 diabetes, and type 2 diabetes.. Adults with diabetes for ≥ 5 years, without renal impairment, were studied (HNF1A MODY [n = 54], HNF4A MODY [n = 23], glucokinase MODY [n = 20], type 1 diabetes [n = 69], and type 2 diabetes [n = 54]). The UCPCR was collected in boric acid 120 min after the largest meal of the day and mailed for analysis. Receiver operating characteristic (ROC) curves were used to identify optimal UCPCR cutoffs to differentiate HNF1A/4A MODY from type 1 and type 2 diabetes.. UCPCR was lower in type 1 diabetes than HNF1A/4A MODY (median [interquartile range]) (<0.02 nmol/mmol [<0.02 to <0.02] vs. 1.72 nmol/mmol [0.98-2.90]; P < 0.0001). ROC curves showed excellent discrimination (area under curve [AUC] 0.98) and identified a cutoff UCPCR of ≥ 0.2 nmol/mmol for differentiating HNF1A/4A MODY from type 1 diabetes (97% sensitivity, 96% specificity). UCPCR was lower in HNF1A/4A MODY than in type 2 diabetes (1.72 nmol/mmol [0.98-2.90] vs. 2.47 nmol/mmol [1.4-4.13]); P = 0.007). ROC curves showed a weak distinction between HNF1A/4A MODY and type 2 diabetes (AUC 0.64).. UCPCR is a noninvasive outpatient tool that can be used to discriminate HNF1A and HNF4A MODY from long-duration type 1 diabetes. To differentiate MODY from type 1 diabetes of >5 years' duration, UCPCR could be used to determine whether genetic testing is indicated. Topics: Adult; Aged; Biomarkers; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 4; Humans; Insulin; Male; Middle Aged; Outpatients; ROC Curve | 2011 |
Urine C-peptide creatinine ratio is a noninvasive alternative to the mixed-meal tolerance test in children and adults with type 1 diabetes.
Stimulated serum C-peptide (sCP) during a mixed-meal tolerance test (MMTT) is the gold standard measure of endogenous insulin secretion, but practical issues limit its use. We assessed urine C-peptide creatinine ratio (UCPCR) as an alternative.. Seventy-two type 1 diabetic patients (age of diagnosis median 14 years [interquartile range 10-22]; diabetes duration 6.5 [2.3-32.7]) had an MMTT. sCP was collected at 90 min. Urine for UCPCR was collected at 120 min and following a home evening meal.. MMTT 120-min UCPCR was highly correlated to 90-min sCP (r = 0.97; P < 0.0001). UCPCR ≥ 0.53 nmol/mmol had 94% sensitivity/100% specificity for significant endogenous insulin secretion (90-min sCP ≥ 0.2 nmol/L). The 120-min postprandial evening meal UCPCR was highly correlated to 90-min sCP (r = 0.91; P < 0.0001). UCPCR ≥ 0.37 nmol/mmol had 84% sensitivity/97% specificity for sCP ≥ 0.2 nmol/L.. UCPCR testing is a sensitive and specific method for detecting insulin secretion. UCPCR may be a practical alternative to serum C-peptide testing, avoiding the need for inpatient investigation. Topics: Adolescent; Adult; Aged; Aged, 80 and over; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; Middle Aged; Young Adult | 2011 |
Evidence that nasal insulin induces immune tolerance to insulin in adults with autoimmune diabetes.
Insulin in pancreatic β-cells is a target of autoimmunity in type 1 diabetes. In the NOD mouse model of type 1 diabetes, oral or nasal administration of insulin induces immune tolerance to insulin and protects against autoimmune diabetes. Evidence for tolerance to mucosally administered insulin or other autoantigens is poorly documented in humans. Adults with recent-onset type 1 diabetes in whom the disease process is subacute afford an opportunity to determine whether mucosal insulin induces tolerance to insulin subsequently injected for treatment.. We randomized 52 adults with recent-onset, noninsulin-requiring type 1 diabetes to nasal insulin or placebo for 12 months. Fasting blood glucose and serum C-peptide, glucagon-stimulated serum C-peptide, and serum antibodies to islet antigens were monitored three times monthly for 24 months. An enhanced ELISpot assay was used to measure the T-cell response to human proinsulin.. β-Cell function declined by 35% overall, and 23 of 52 participants (44%) progressed to insulin treatment. Metabolic parameters remained similar between nasal insulin and placebo groups, but the insulin antibody response to injected insulin was significantly blunted in a sustained manner in those who had received nasal insulin. In a small cohort, the interferon-γ response of blood T-cells to proinsulin was suppressed after nasal insulin.. Although nasal insulin did not retard loss of residual β-cell function in adults with established type 1 diabetes, evidence that it induced immune tolerance to insulin provides a rationale for its application to prevent diabetes in at-risk individuals. Topics: Administration, Intranasal; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Fasting; Female; Humans; Hypoglycemic Agents; Immune Tolerance; Insulin; Insulin Antibodies; Male; Middle Aged; Placebos; T-Lymphocytes | 2011 |
Residual beta cell function in newly diagnosed type 1 diabetes after treatment with atorvastatin: the Randomized DIATOR Trial.
Recent evidence suggests that the lipid-lowering agent atorvastatin is also a potent immunomodulator. The aim of this study was to investigate the possible effect of atorvastatin on the decline of residual beta cell function in recent-onset type 1 diabetes.. The randomised placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and islet autoantibodies (mean age 30 years, 40% females), in 12 centres in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. An intent-to-treat analysis was performed. Fasting and stimulated C-peptide levels were not significantly different between groups at 18 months. However, median fasting serum C-peptide levels dropped from baseline to 12 and 18 months in the placebo group (from 0. 34 to 0.23 and 0.20 nmol/l, p<0.001) versus a nonsignificant decline in the atorvastatin group (from 0.34 to 0.27 and 0.30 nmol/l, ns). Median stimulated C-peptide concentrations declined between baseline and 12 months (placebo from 0.89 to 0.71 nmol/l, atorvastatin from 0.88 to 0.73 nmol/l, p<0.01 each) followed by a major loss by month 18 in the placebo group (to 0.48 nmol/l, p = 0.047) but not in the atorvastatin group (to 0.71 nmol/l, ns). Median levels of total cholesterol and C-reactive protein decreased in the atorvastatin group only (p<0.001 and p = 0.04). Metabolic control was similar between groups.. Atorvastatin treatment did not significantly preserve beta cell function although there may have been a slower decline of beta-cell function which merits further study.. ClinicalTrials.gov NCT00974740. Topics: Adult; Atorvastatin; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Heptanoic Acids; Humans; Insulin-Secreting Cells; Lipids; Male; Pyrroles; Treatment Outcome | 2011 |
Antidiabetic actions of endogenous and exogenous GLP-1 in type 1 diabetic patients with and without residual β-cell function.
To investigate the effect of exogenous as well as endogenous glucagon-like peptide 1 (GLP-1) on postprandial glucose excursions and to characterize the secretion of incretin hormones in type 1 diabetic patients with and without residual β-cell function.. Eight type 1 diabetic patients with (T1D+), eight without (T1D-) residual β-cell function, and eight healthy matched control subjects were studied during a mixed meal with concomitant infusion of GLP-1 (1.2 pmol/kg/min), saline, or exendin 9-39 (300 pmol/kg/min). Before the meal, half dose of usual fast-acting insulin was injected. Plasma glucose (PG), glucagon, C-peptide, total GLP-1, intact glucose-dependent insulinotropic polypeptide (GIP), free fatty acids, triglycerides, and gastric emptying rate (GE) by plasma acetaminophen were measured.. Incretin responses did not differ between patients and control subjects. Infusion of GLP-1 decreased peak PG by 45% in both groups of type 1 diabetic patients. In T1D+ patients, postprandial PG decreased below fasting levels and was indistinguishable from control subjects infused with saline. In T1D- patients, postprandial PG remained at fasting levels. GLP-1 infusion reduced GE and glucagon levels in all groups and increased fasting C-peptide in T1D+ patients and control subjects. Blocking endogenous GLP-1 receptor action increased endogenous GLP-1 secretion in all groups and increased postprandial glucose, glucagon, and GE in T1D+ and T1D- patients. The insulinogenic index (the ratio of insulin to glucose) decreased in T1D+ patients during blockade of endogenous GLP-1 receptor action.. Type 1 diabetic patients have normal incretin responses to meals. In type 1 diabetic patients, exogenous GLP-1 decreases peak postprandial glucose by 45% regardless of residual β-cell function. Endogenous GLP-1 regulates postprandial glucose excursions by modulating glucagon levels, GE, and β-cell responsiveness to glucose. Long-term effects of GLP-1 in type 1 diabetic patients should be investigated in future clinical trials. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gastric Emptying; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Peptide Fragments; Triglycerides; Young Adult | 2011 |
Preliminary studies related to anti-interleukin-1β therapy in children with newly diagnosed type 1 diabetes.
Interleukin-1β (IL-1β) may play a role in the pathogenesis of type 1 diabetes, but there are no data regarding the efficacy of agents antagonizing IL-1β in patients with this disorder. We characterized the effects of IL-1β on gene expression in peripheral blood mononuclear cells (PBMC) and the clinical and gene expression effects of a short course of recombinant IL-1 receptor antagonist protein, anakinra, on children with newly diagnosed diabetes.. PBMC from healthy adult volunteers were exposed to IL-1β for 24 h in vitro. Gene expression was analyzed via microarray. Fifteen children within 1 wk of diagnosis of type 1 diabetes received daily anakinra for 28 d and were followed for 6 months. Blood was drawn for microarray analysis before and after anakinra treatment. Insulin secretory capacity was assessed by mixed-meal tolerance testing (MMTT) at 3-4 wk and 7 months after diagnosis. Hemoglobin A1c (HbA1c) and insulin doses were periodically recorded. Data were compared with two historical control groups of children with newly diagnosed diabetes.. Although in vitro exposure to IL-1β caused many changes in PBMC gene expression, gene expression did not change significantly after anakinra therapy in diabetes patients. Anakinra-treated patients had similar HbA1c and MMTT responses, but lower insulin requirements 1 and 4 months after diagnosis compared to controls, and lower insulin-dose-adjusted A1c 1 month after diagnosis.. Anakinra therapy is well tolerated in children with newly diagnosed type 1 diabetes. Further studies are needed to demonstrate biological effects. Topics: Adolescent; Adult; Antirheumatic Agents; Area Under Curve; C-Peptide; Cells, Cultured; Child; Diabetes Mellitus, Type 1; Female; Gene Expression Profiling; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Insulin Secretion; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Leukocytes, Mononuclear; Male; Oligonucleotide Array Sequence Analysis; Pilot Projects | 2011 |
Four weeks of treatment with liraglutide reduces insulin dose without loss of glycemic control in type 1 diabetic patients with and without residual beta-cell function.
To investigate the effect of 4 weeks of treatment with liraglutide on insulin dose and glycemic control in type 1 diabetic patients with and without residual β-cell function.. Ten type 1 diabetic patients with residual β-cell function (C-peptide positive) and 19 without (C-peptide negative) were studied. All C-peptide-positive patients were treated with liraglutide plus insulin, whereas C-peptide-negative patients were randomly assigned to liraglutide plus insulin or insulin monotherapy. Continuous glucose monitoring with identical food intake and physical activity was performed before (week 0) and during (week 4) treatment. Differences in insulin dose; HbA1c; time spent with blood glucose<3.9, >10, and 3.9-9.9 mmol/L; and body weight were evaluated.. Insulin dose decreased from 0.50±0.06 to 0.31±0.08 units/kg per day (P<0.001) in C-peptide-positive patients and from 0.72±0.08 to 0.59±0.06 units/kg per day (P<0.01) in C-peptide-negative patients treated with liraglutide but did not change with insulin monotherapy. HbA1c decreased in both liraglutide-treated groups. The percent reduction in daily insulin dose was positively correlated with β-cell function at baseline, and two patients discontinued insulin treatment. In C-peptide-positive patients, time spent with blood glucose<3.9 mmol/L decreased from 3.0 to 1.0 h (P=0.03). A total of 18 of 19 patients treated with liraglutide lost weight during treatment (mean [range] -2.3±0.3 kg [-0.5 to -5.1]; P<0.001). Transient gastrointestinal adverse effects occurred in almost all patients treated with liraglutide.. Treatment with liraglutide in type 1 diabetic patients reduces insulin dose with improved or unaltered glycemic control. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exercise Test; Female; Glucagon-Like Peptide 1; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Liraglutide; Male; Middle Aged; Weight Loss | 2011 |
Insulin pump therapy started at the time of diagnosis: effects on glycemic control and pancreatic β-cell function in type 1 diabetes.
In the interest of preserving residual insulin secretory capacity present at the time of diagnosis with type 1 diabetes (T1D), we compared the efficacy of starting insulin pump therapy at diagnosis with standard multiple daily insulin injections (MDIs).. We conducted a prospective, randomized, pilot trial comparing MDI therapy with continuous subcutaneous insulin therapy (pump therapy) in 24 patients, 8-18 years old, with newly diagnosed T1D. Subjects were evaluated at enrollment and 1, 3, 6, 9, and 12 months after initial diagnosis of T1D. Preservation of insulin secretion, measured by mixed-meal-stimulated C-peptide secretion, was compared after 6 and 12 months of treatment. Between-group differences in glycosylated hemoglobin (HbA1c), continuous glucose sensor data, insulin utilization, anthropometric measures, and patient satisfaction with therapy were also compared at multiple time points.. Initiation of pump therapy within 1 month of diagnosis resulted in consistently higher mixed-meal tolerance test-stimulated C-peptide values at all time points, although these differences were not statistically significant. Nonetheless, improved glycemic control was observed in insulin pump-treated subjects (more time spent with normoglycemia, better mean HbA1c), and pump-treated subjects reported comparatively greater satisfaction with route of treatment administration.. Initiation of insulin pump therapy at diagnosis improved glycemic control, was well tolerated, and contributed to improved patient satisfaction with treatment. This study also suggests that earlier use of pump therapy might help to preserve residual β-cell function, although a larger clinical trial would be required to confirm this. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Infusion Pumps, Implantable; Insulin; Insulin Infusion Systems; Insulin-Secreting Cells; Male; Patient Satisfaction; Pilot Projects; Prospective Studies | 2011 |
Teplizumab for treatment of type 1 diabetes (Protégé study): 1-year results from a randomised, placebo-controlled trial.
Findings of small studies have suggested that short treatments with anti-CD3 monoclonal antibodies that are mutated to reduce Fc receptor binding preserve β-cell function and decrease insulin needs in patients with recent-onset type 1 diabetes. In this phase 3 trial, we assessed the safety and efficacy of one such antibody, teplizumab.. In this 2-year trial, patients aged 8-35 years who had been diagnosed with type 1 diabetes for 12 weeks or fewer were enrolled and treated at 83 clinical centres in North America, Europe, Israel, and India. Participants were allocated (2:1:1:1 ratio) by an interactive telephone system, according to computer-generated block randomisation, to receive one of three regimens of teplizumab infusions (14-day full dose, 14-day low dose, or 6-day full dose) or placebo at baseline and at 26 weeks. The Protégé study is still underway, and patients and study staff remain masked through to study closure. The primary composite outcome was the percentage of patients with insulin use of less than 0·5 U/kg per day and glycated haemoglobin A(1c) (HbA(1C)) of less than 6·5% at 1 year. Analyses included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT00385697.. 763 patients were screened, of whom 516 were randomised to receive 14-day full-dose teplizumab (n=209), 14-day low-dose teplizumab (n=102), 6-day full-dose teplizumab (n=106), or placebo (n=99). Two patients in the 14-day full-dose group and one patient in the placebo group did not start treatment, so 513 patients were eligible for efficacy analyses. The primary outcome did not differ between groups at 1 year: 19·8% (41/207) in the 14-day full-dose group; 13·7% (14/102) in the 14-day low-dose group; 20·8% (22/106) in the 6-day full-dose group; and 20·4% (20/98) in the placebo group. 5% (19/415) of patients in the teplizumab groups were not taking insulin at 1 year, compared with no patients in the placebo group at 1 year (p=0·03). Across the four study groups, similar proportions of patients had adverse events (414/417 [99%] in the teplizumab groups vs 98/99 [99%] in the placebo group) and serious adverse events (42/417 [10%] vs 9/99 [9%]). The most common clinical adverse event in the teplizumab groups was rash (220/417 [53%] vs 20/99 [20%] in the placebo group).. Findings of exploratory analyses suggest that future studies of immunotherapeutic intervention with teplizumab might have increased success in prevention of a decline in β-cell function (measured by C-peptide) and provision of glycaemic control at reduced doses of insulin if they target patients early after diagnosis of diabetes and children.. MacroGenics, the Juvenile Diabetes Research Foundation, and Eli Lilly. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Canada; CD3 Complex; Child; Diabetes Mellitus, Type 1; Drug Administration Schedule; Drug Eruptions; Europe; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; India; Insulin; Insulin-Secreting Cells; Israel; Male; Mexico; Muromonab-CD3; Treatment Outcome; United States; Young Adult | 2011 |
Increased T cell proliferative responses to islet antigens identify clinical responders to anti-CD20 monoclonal antibody (rituximab) therapy in type 1 diabetes.
Type 1 diabetes mellitus is believed to be due to the autoimmune destruction of β-cells by T lymphocytes, but a single course of rituximab, a monoclonal anti-CD20 B lymphocyte Ab, can attenuate C-peptide loss over the first year of disease. The effects of B cell depletion on disease-associated T cell responses have not been studied. We compare changes in lymphocyte subsets, T cell proliferative responses to disease-associated target Ags, and C-peptide levels of participants who did (responders) or did not (nonresponders) show signs of β-cell preservation 1 y after rituximab therapy in a placebo-controlled TrialNet trial. Rituximab decreased B lymphocyte levels after four weekly doses of mAb. T cell proliferative responses to diabetes-associated Ags were present at baseline in 75% of anti-CD20- and 82% of placebo-treated subjects and were not different over time. However, in rituximab-treated subjects with significant C-peptide preservation at 6 mo (58%), the proliferative responses to diabetes-associated total (p = 0.032), islet-specific (p = 0.048), and neuronal autoantigens (p = 0.005) increased over the 12-mo observation period. This relationship was not seen in placebo-treated patients. We conclude that in patients with type 1 diabetes mellitus, anti-B cell mAb causes increased proliferative responses to diabetes Ags and attenuated β-cell loss. The way in which these responses affect the disease course remains unknown. Topics: Adolescent; Adult; Antibodies, Monoclonal, Murine-Derived; Autoantigens; C-Peptide; Cell Proliferation; Child; Diabetes Mellitus, Type 1; Female; Humans; Immunologic Factors; Insulin-Secreting Cells; Male; Rituximab; T-Lymphocyte Subsets; Time Factors | 2011 |
Decreased active GLP-1 response following large test meal in patients with type 1 diabetes using bolus insulin analogues.
Postprandial plasma immunoreactive active glucagon-like peptide-1 (p-active GLP-1) levels in type 1 diabetic patients who did not use bolus insulin responded normally following ingestion of test meal, while a small response of p-active GLP-1 levels was seen in type 2 diabetic patients. To determine whether p-active GLP-1 levels are affected by ingestion of test meal in type 1 diabetic Japanese patients who used bolus rapid-acting insulin analogues, plasma glucose (PG), serum immunoreactive insulin (s-IRI), serum immunoreactive C-peptide (s-CPR), and p-active GLP-1 levels were measured 0, 30, and 60 min after ingestion of test meal in Japanese patients without diabetic complications (n=10, group 1) and control subjects with normal glucose tolerance (n=15, group 2). HbA1c levels were also measured in these groups. The patients in group 1 were treated with multiple daily injections or CSII using injections of bolus rapid-acting insulin analogues before ingestion of test meal. There was no significant difference in mean of sex, age, or BMI between groups. Means of HbA1c, basal and postprandial PG, and postprandial s-IRI levels with integrated areas under curves (0-60 min) (AUC) in group 1 were significantly higher than those in group 2. Means of basal and postprandial s-CPR, and postprandial p-active GLP-1 levels with AUCs were significantly lower in group 1 than in group 2. These results indicated that postprandial p-active GLP-1 levels following ingestion of test meal in type 1 diabetic Japanese patients using bolus rapid-acting insulin analogues were decreased relative to those in controls. Topics: Biphasic Insulins; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon-Like Peptide 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin, Short-Acting; Male; Middle Aged; Postprandial Period | 2011 |
C-peptide response and HLA genotypes in subjects with recent-onset type 1 diabetes after immunotherapy with DiaPep277: an exploratory study.
To investigate whether lower risk HLA class II genotypes would influence the efficacy of DiaPep277 therapy in protecting β-cell function evaluated by C-peptide secretion in recent-onset type 1 diabetic subjects.. Data were collected from type 1 diabetic subjects enrolled in multicenter phase II studies with a randomized, double-blind, and placebo-controlled design in whom fasting and stimulated C-peptide levels were measured. HLA genotypes were classified in high, moderate, and low risk categories.. A total of 146 subjects (aged 4.3 to 58.5 years) were enrolled, including 76 children (<18 years old) and 70 adults. At baseline, there was a significant increase in fasting, maximal, and area under the curve (AUC) C-peptide from high to moderate and low risk HLA genotypes in adults (P for trend <0.04) but not in children. Children showed a decrease of the three parameters over time regardless of therapy and HLA genotype. DiaPep277-treated adults with low risk genotype had significantly higher maximal and AUC C-peptide versus placebo at 12 months (0.04 ± 0.07 vs. -0.28 ± 0.09 nmol/L, P < 0.01, and 0.53 ± 1.3 vs. -4.59 ± 1.5 nmol/L, P < 0.05, respectively). In the moderate risk genotype group, Δmaximal and AUC C-peptide values were significantly higher in DiaPep277-treated versus placebo-treated patients (P < 0.01 and P < 0.05, respectively).. This exploratory study demonstrates that type 1 diabetic adults with low and moderate risk HLA genotypes benefit the most from intervention with DiaPep277; the only subgroup with an increase of C-peptide at 12 months after diagnosis was the low risk DiaPep277-treated subgroup. Topics: Adolescent; Adult; Age Factors; C-Peptide; Chaperonin 60; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Genes, MHC Class II; Genetic Association Studies; Humans; Hypoglycemic Agents; Immunologic Factors; Insulin-Secreting Cells; Kinetics; Male; Middle Aged; Peptide Fragments; Young Adult | 2011 |
Autologous umbilical cord blood transfusion in young children with type 1 diabetes fails to preserve C-peptide.
We conducted an open-label, phase I study using autologous umbilical cord blood (UCB) infusion to ameliorate type 1 diabetes (T1D). Having previously reported on the first 15 patients reaching 1 year of follow-up, herein we report on the complete cohort after 2 years of follow-up.. A total of 24 T1D patients (median age 5.1 years) received a single intravenous infusion of autologous UCB cells and underwent metabolic and immunologic assessments.. No infusion-related adverse events were observed. β-Cell function declined after UCB infusion. Area under the curve C-peptide was 24.3% of baseline 1 year postinfusion (P < 0.001) and 2% of baseline 2 years after infusion (P < 0.001). Flow cytometry revealed increased regulatory T cells (Tregs) (P = 0.04) and naive Tregs (P = 0.001) 6 and 9 months after infusion, respectively.. Autologous UCB infusion in children with T1D is safe and induces changes in Treg frequency but fails to preserve C-peptide. Topics: Blood Transfusion, Autologous; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Fetal Blood; Follow-Up Studies; Humans; Infant; Male; Pilot Projects; T-Lymphocytes, Regulatory | 2011 |
Sample size requirements for studies of treatment effects on beta-cell function in newly diagnosed type 1 diabetes.
Preservation of β-cell function as measured by stimulated C-peptide has recently been accepted as a therapeutic target for subjects with newly diagnosed type 1 diabetes. In recently completed studies conducted by the Type 1 Diabetes Trial Network (TrialNet), repeated 2-hour Mixed Meal Tolerance Tests (MMTT) were obtained for up to 24 months from 156 subjects with up to 3 months duration of type 1 diabetes at the time of study enrollment. These data provide the information needed to more accurately determine the sample size needed for future studies of the effects of new agents on the 2-hour area under the curve (AUC) of the C-peptide values. The natural log(x), log(x+1) and square-root (√x) transformations of the AUC were assessed. In general, a transformation of the data is needed to better satisfy the normality assumptions for commonly used statistical tests. Statistical analysis of the raw and transformed data are provided to estimate the mean levels over time and the residual variation in untreated subjects that allow sample size calculations for future studies at either 12 or 24 months of follow-up and among children 8-12 years of age, adolescents (13-17 years) and adults (18+ years). The sample size needed to detect a given relative (percentage) difference with treatment versus control is greater at 24 months than at 12 months of follow-up, and differs among age categories. Owing to greater residual variation among those 13-17 years of age, a larger sample size is required for this age group. Methods are also described for assessment of sample size for mixtures of subjects among the age categories. Statistical expressions are presented for the presentation of analyses of log(x+1) and √x transformed values in terms of the original units of measurement (pmol/ml). Analyses using different transformations are described for the TrialNet study of masked anti-CD20 (rituximab) versus masked placebo. These results provide the information needed to accurately evaluate the sample size for studies of new agents to preserve C-peptide levels in newly diagnosed type 1 diabetes. Topics: Adolescent; Adult; Age Factors; Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal, Murine-Derived; Area Under Curve; C-Peptide; Child; Cohort Studies; Daclizumab; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Immunoglobulin G; Immunologic Factors; Immunosuppressive Agents; Insulin-Secreting Cells; Male; Middle Aged; Mycophenolic Acid; Rituximab; Sample Size; Young Adult | 2011 |
A clinical trial of xenotransplantation of neonatal pig islets for diabetic patients.
To ascertain the safety and function of the transplantation of neonatal pig islets (NPIs) for diabetic patients.. NPIs were injected into the hepatic artery of 22 patients. After the transplantation, the patients were treated with a multiple drug immunosuppressive regimens. The first 14 patients were treated with cyclosporine (CsA), mycophenolate mofetil (MMF) and prednisolon, and porcine C-peptide was not monitored, the following 2 patients were given cyklosporin and MMF only, while the next 6 patients were given a quadruple drug regimen consisting of OKT3, takrolimus, sirolimus and prednisolon. The blood glucose levels,exogenous insulin requirement,HbA1c, porcine endogenous retrovirus (PERV) and liver function were assessed before and after NPI transplantation. The serum porcine C peptide were monitored in last 8 patients.. The first 14 patients required less insulin and the HbA1c dropped after the transplantation. In the 2 subsequent patients, the metabolic parameters remained unchanged and monitor of porcine C-peptide was negative. Insulin requirements were reduced in all 6 patients, and HbA1c was normalized 3 months after the transplantation. Significant levels of porcine C-peptide were detected in the patient serum. Two of the patients were given a second injection of NPIs, and one of them became insulin independent for 7 d. No serious adverse events were noted after the transplantation. There was no evidence of PERV transmission. Six out of the 22 patients were followed up for 4-6 years after the NPIs injection, immunosuppressive treatment was stopped 1 year after the transplantation. The patients started to take insulin at the time of follow up. Four patients restricted the intake of sugar, while the other 2 did not. One patient had ketoacidosis twice and slight diabetic retinopathy, and another patient had ketoacidosis induced by acute gastroenteritis. The remaining 4 patients did not have any complications. Assays for PERV were again negative.. Xenogenic islets can survive and function in the human body. No serious adverse events are noted. Topics: Adolescent; Adult; Animals; Animals, Newborn; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Dogs; Female; Follow-Up Studies; Hepatic Artery; Humans; Immunosuppressive Agents; Injections, Intra-Arterial; Islets of Langerhans Transplantation; Male; Mice; Mice, Nude; Middle Aged; Swine; Transplantation, Heterologous; Young Adult | 2011 |
Association of T-cell reactivity with beta-cell function in recent onset type 1 diabetes patients.
The aim of the current study was to investigate whether autoantigen directed T-cell reactivity relates to beta-cell function during the first 78 weeks after diagnosis of type 1 diabetes.. 50 adults and 49 children (mean age 27.3 and 10.9 years respectively) with recent onset type 1 diabetes who participated in a placebo-controlled trial of immune intervention with DiaPep277 were analyzed. Secretion of interferon (IFN)-gamma, interleukin (IL)-5, IL-13 and IL-10 by single peripheral mononuclear cells (PBMC) upon stimulation with islet antigens GAD65, heat shock protein 60 (Hsp60) protein-tyrosine-phosphatase-like-antigen (pIA2) or tetanus toxoid (TT) was determined applying ELISPOT; beta-cell function was evaluated by glucagon stimulated C-peptide. Multivariate regression analysis was applied.. In general, number of islet antigen-reactive cells decreased over 78 weeks in both adults and children, whereas reactivity to TT was not reduced. In addition, there was an association between the quality of immune cell responses and beta-cell function. Overall, increased responses by IFN-gamma secreting cells were associated with lower beta-cell function whereas IL-5, IL-13 and IL-10 cytokine responses were positively associated with beta-cell function in adults and children. Essentially, the same results were obtained with three different models of regression analysis.. The number of detectable islet-reactive immune cells decreases within 1-2 years after diagnosis of type 1 diabetes. Cytokine production by antigen-specific PBMC reactivity is related to beta-cell function as measured by stimulated C-peptide. Cellular immunity appears to regress soon after disease diagnosis and begin of insulin therapy. Topics: Adolescent; Adult; Autoantigens; C-Peptide; Cells, Cultured; Child; Cytokines; Diabetes Mellitus, Type 1; Disease Progression; Female; Follow-Up Studies; Glucagon; Humans; Insulin-Secreting Cells; Male; T-Cell Antigen Receptor Specificity; Th1 Cells; Th2 Cells | 2010 |
Do the actions of glucagon-like peptide-1 on gastric emptying, appetite, and food intake involve release of amylin in humans?
Amylin, cosecreted with insulin, has like glucagon-like peptide-1 (GLP-1) been reported to inhibit glucagon secretion, delay gastric emptying, and reduce appetite and food intake. We investigated whether the effects of GLP-1 on gastric emptying, appetite, and food intake are mediated directly or indirectly via release of amylin.. Eleven C-peptide and amylin-negative patients with type 1 diabetes mellitus (T1DM) and 12 matched healthy controls participated in a placebo-controlled, randomized, single-blinded, crossover study. With glucose clamped between 6 and 9 mm, near-physiological infusions of GLP-1, human amylin, pramlintide, or saline were given for 270 min during and after a fixed meal. Gastric emptying was measured using paracetamol, appetite using visual analog scales, and food intake during a subsequent ad libitum meal (at 240 min).. In T1DM, gastric emptying, food intake, and appetite were reduced equally during low GLP-1 and amylin infusion compared with the saline infusion (P < 0.05). The controls showed stronger suppression of gastric emptying (P < 0.0001) and food intake (P < 0.01) with GLP-1 compared to amylin. Postprandial glucagon responses were reduced in controls and T1DM during GLP-1 and amylin infusions (P < 0.05). Amylin and pramlintide infusion had similar effects.. GLP-1 exerts its effect on gastric emptying, appetite, food intake, and glucagon secretion directly, although secretion of amylin may contribute to some of these effects in healthy control subjects. Topics: Adult; Amyloid; Appetite; Body Mass Index; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Gastric Emptying; Glucagon; Glucagon-Like Peptide 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Islet Amyloid Polypeptide; Reference Values; Single-Blind Method | 2010 |
GAD-alum treatment in patients with type 1 diabetes and the subsequent effect on GADA IgG subclass distribution, GAD65 enzyme activity and humoral response.
We have previously shown that two injections of 20 μg GAD-alum to recent onset type 1 diabetic children induced GADA levels in parallel to preservation of insulin secretion. Here we investigated if boosted GADA induced changes in IgG1, 2, 3 and 4 subclass distributions or affected GAD(65) enzyme activity. We further studied the specific effect of GAD-alum through analyses of IA-2A, tetanus toxoid and total IgE antibodies. Serum from children receiving GAD-alum or placebo was collected pre-treatment and after 3, 9, 15 and 21 months. At 3 months a reduced percentage of IgG1 and increased IgG3/IgG4 were detected in GAD-alum treated. Further, IA-2A, IgE and tetanus toxoid antibodies, as well as GAD(65) enzyme activity, were unaffected confirming the specific effect of treatment. In the GAD-alum group, higher pre-treatment GADA were associated to more pronounced C-peptide preservation. The induced IgG3/IgG4 and reduced IgG1 suggest a Th2 deviation of the immune response. Topics: Adjuvants, Immunologic; Adolescent; Alum Compounds; Antibodies; Area Under Curve; Autoantibodies; Biocatalysis; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Glutamate Decarboxylase; Humans; Immune Sera; Immunity, Humoral; Immunoglobulin E; Immunoglobulin G; Immunotherapy, Active; Tetanus Toxoid; Treatment Outcome | 2010 |
No protective effect of calcitriol on beta-cell function in recent-onset type 1 diabetes: the IMDIAB XIII trial.
We investigated whether supplementation of the active form of vitamin D (calcitriol) in recent-onset type 1 diabetes can protect beta-cell function evaluated by C-peptide and improve glycemic control assessed by A1C and insulin requirement.. Thirty-four subjects (aged 11-35 years, median 18 years) with recent-onset type 1 diabetes and high basal C-peptide >0.25 nmol/l were randomized in a double-blind trial to 0.25 microg/day calcitriol or placebo and followed-up for 2 years.. At 6, 12, and 24 months follow-up, A1C and insulin requirement in the calcitriol group did not differ from the placebo group. C-peptide dropped significantly (P < 0.001) but similarly in both groups, with no significant differences at each time point.. At the doses used, calcitriol is ineffective in protecting beta-cell function in subjects (including children) with recent-onset type 1 diabetes and high C-peptide at diagnosis. Topics: Adolescent; Adult; C-Peptide; Calcitriol; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Young Adult | 2010 |
Rosiglitazone preserves islet beta-cell function of adult-onset latent autoimmune diabetes in 3 years follow-up study.
The newly developed insulin sensitizer-thiazolidinediones have the potential to downregulate inflammation and autoimmune response. The objective of this study was to observe the beneficial effects on beta-cell function in the LADA patients treated with rosiglitazone. 54 LADA patients were assigned to oral hypoglycemic agents group (GAD-Ab<175 U/mL and FCP>0.3 nmol/L) or early insulin administration group (GAD-Ab>or=175 U/mL or GAD-Ab<175 U/mL and FCP Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Male; Middle Aged; Rosiglitazone; Sulfonylurea Compounds; Thiazolidinediones | 2009 |
C-peptide levels and insulin independence following autologous nonmyeloablative hematopoietic stem cell transplantation in newly diagnosed type 1 diabetes mellitus.
In 2007, the effects of the autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT) in 15 patients with type 1 diabetes mellitus (DM) were reported. Most patients became insulin free with normal levels of glycated hemoglobin A(1c) (HbA(1c)) during a mean 18.8-month follow-up. To investigate if this effect was due to preservation of beta-cell mass, continued monitoring was performed of C-peptide levels after stem cell transplantation in the 15 original and 8 additional patients.. To determine C-peptide levels after autologous nonmyeloablative HSCT in patients with newly diagnosed type 1 DM during a longer follow-up.. A prospective phase 1/2 study of 23 patients with type 1 DM (aged 13-31 years) diagnosed in the previous 6 weeks by clinical findings with hyperglycemia and confirmed by measurement of serum levels of anti-glutamic acid decarboxylase antibodies. Enrollment was November 2003-April 2008, with follow-up until December 2008 at the Bone Marrow Transplantation Unit of the School of Medicine of Ribeirão Preto, Ribeirão Preto, Brazil. Hematopoietic stem cells were mobilized via the 2007 protocol.. C-peptide levels measured during the mixed-meal tolerance test, before, and at different times following HSCT. Secondary end points included morbidity and mortality from transplantation, temporal changes in exogenous insulin requirements, and serum levels of HbA(1c).. During a 7- to 58-month follow-up (mean, 29.8 months; median, 30 months), 20 patients without previous ketoacidosis and not receiving corticosteroids during the preparative regimen became insulin free. Twelve patients maintained this status for a mean 31 months (range, 14-52 months) and 8 patients relapsed and resumed insulin use at low dose (0.1-0.3 IU/kg). In the continuous insulin-independent group, HbA(1c) levels were less than 7.0% and mean (SE) area under the curve (AUC) of C-peptide levels increased significantly from 225.0 (75.2) ng/mL per 2 hours pretransplantation to 785.4 (90.3) ng/mL per 2 hours at 24 months posttransplantation (P < .001) and to 728.1 (144.4) ng/mL per 2 hours at 36 months (P = .001). In the transient insulin-independent group, mean (SE) AUC of C-peptide levels also increased from 148.9 (75.2) ng/mL per 2 hours pretransplantation to 546.8 (96.9) ng/mL per 2 hours at 36 months (P = .001), which was sustained at 48 months. In this group, 2 patients regained insulin independence after treatment with sitagliptin, which was associated with increase in C-peptide levels. Two patients developed bilateral nosocomial pneumonia, 3 patients developed late endocrine dysfunction, and 9 patients developed oligospermia. There was no mortality.. After a mean follow-up of 29.8 months following autologous nonmyeloablative HSCT in patients with newly diagnosed type 1 DM, C-peptide levels increased significantly and the majority of patients achieved insulin independence with good glycemic control.. clinicaltrials.gov Identifier: NCT00315133. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Hematopoietic Stem Cell Mobilization; Hematopoietic Stem Cell Transplantation; Humans; Hypoglycemic Agents; Insulin; Male; Prospective Studies; Transplantation Conditioning; Transplantation, Autologous; Young Adult | 2009 |
Pancreatic beta cell function persists in many patients with chronic type 1 diabetes, but is not dramatically improved by prolonged immunosuppression and euglycaemia from a beta cell allograft.
We measured serum C-peptide (at least 0.167 nmol/l) in 54 of 141 (38%) patients with chronic type 1 diabetes and sought factors that might differentiate those with detectable C-peptide from those without it. Finding no differences, and in view of the persistent anti-beta cell autoimmunity in such patients, we speculated that the immunosuppression (to weaken autoimmune attack) and euglycaemia accompanying transplant-based treatments of type 1 diabetes might promote recovery of native pancreatic beta cell function.. We performed arginine stimulation tests in three islet transplant and four whole-pancreas transplant recipients, and measured stimulated C-peptide in select venous sampling sites. On the basis of each sampling site's C-peptide concentration and kinetics, we differentiated insulin secreted from the individual's native pancreatic beta cells and that secreted from allografted beta cells.. Selective venous sampling demonstrated that despite long-standing type 1 diabetes, all seven beta cell allograft recipients displayed evidence that their native pancreas secreted C-peptide. Yet even if chronic immunosuppression coupled with near normal glycaemia did improve native pancreatic C-peptide production, the magnitude of the effect was quite small.. Some native pancreatic beta cell function persists even years after disease onset in most type 1 diabetic patients. However, if prolonged euglycaemia plus anti-rejection immunosuppressive therapy improves native pancreatic insulin production, the effect in our participants was small. We may have underestimated pancreatic regenerative capacity by studying only a limited number of participants or by creating conditions (e.g. high circulating insulin concentrations or immunosuppressive agents toxic to beta cells) that impair beta cell function. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Female; Hepatic Veins; Humans; Immunosuppressive Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Portal Vein; Regeneration; Transplantation, Homologous | 2009 |
Improved glycemic control with intraperitoneal versus subcutaneous insulin in type 1 diabetes: a randomized controlled trial.
OBJECTIVE Continuous intraperitoneal insulin infusion (CIPII) with an implantable pump has been available for the past 25 years. CIPII, with its specific pharmacodynamic properties, may be a viable treatment alternative to improve glycemic control in patients with type 1 diabetes for whom other therapies have failed. There have been few studies in which CIPII was compared with subcutaneous insulin treatment for patients with type 1 diabetes with poor glycemic control. RESEARCH DESIGN AND METHODS In an open-label, prospective, crossover, randomized, 16-month study, the effects of CIPII and subcutaneous insulin were compared in 24 patients. The primary outcome measure was the incidence of hypoglycemia. Secondary outcome measures were A1C, and glucose profile, including time in euglycemia, as measured by continuous glucose monitoring. RESULTS The incidence of grade 1 hypoglycemic events was 4.0 +/- 2.6 per week with subcutaneous insulin compared with 3.5 +/- 2.3 per week during CIPII (P = 0.13). The absolute mean difference in A1C with CIPII compared with subcutaneous treatment was -0.76% (95% CI -1.41 to -0.11) (P = 0.03). Baseline time spent in euglycemia was 45.2 +/- 12.6% and increased 10.9% (4.6-17.3) with CIPII compared with subcutaneous treatment (absolute value; P = 0.003). There were no differences in the occurrence rate for severe hypoglycemic events, daily insulin use, or BMI. No pump or catheter malfunction was observed during the study. CONCLUSIONS Although we did not observe a significant reduction in hypoglycemic events, improved glycemic control was achieved with the use of CIPII. We saw a 0.8% decrease in A1C and an 11% increase in the time spent in euglycemia. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Hypoglycemia; Incidence; Injections, Subcutaneous; Insulin; Insulin Infusion Systems; Middle Aged; Patient Selection; Young Adult | 2009 |
Treatment of patients with new onset Type 1 diabetes with a single course of anti-CD3 mAb Teplizumab preserves insulin production for up to 5 years.
Anti-CD3 mAbs may prolong beta cell function up to 2 years in patients with new onset Type 1 diabetes (T1DM). A randomized open label trial of anti-CD3 mAb, Teplizumab, in T1DM was stopped after 10 subjects because of increased adverse events than in a previous trial related with higher dosing of drug. Teplizumab caused transient reduction in circulating T cells, but the recovered cells were not new thymic emigrants because T cell receptor excision circles were not increased. There was a trend for reduced loss of C-peptide over 2 years with drug treatment (p=0.1), and insulin use was lower (p<0.001). In 4 drug-treated subjects followed up to 60 months, C-peptide responses were maintained. We conclude that increased doses of Teplizumab are associated with greater adverse events without improved efficacy. The drug may marginate rather than deplete T cells. C-peptide levels may remain detectable up to 5 years after treatment. Topics: Adolescent; Antibodies, Monoclonal, Humanized; C-Peptide; CD3 Complex; Child; Diabetes Mellitus, Type 1; Exanthema; Female; Fever; Follow-Up Studies; Gastrointestinal Diseases; Humans; Hypoglycemic Agents; Insulin; Male; Muromonab-CD3; Nausea; Treatment Outcome; Vomiting | 2009 |
Camel milk as an adjuvant therapy for the treatment of type 1 diabetes: verification of a traditional ethnomedical practice.
There is a traditional belief in the Middle East that regular consumption of camel milk may aid in prevention and control of diabetes. The aim of this work was to evaluate the efficacy of camel milk as an adjuvant therapy in young type 1 diabetics. This 16-week randomized study enrolled 54 type 1 diabetic patients (average age 20 years) selected from those attending the outpatient diabetes clinic of the Menofia University Hospital, affiliated with Egypt's National Cancer Institute. Subjects were randomly divided into two groups of 27 patients: one received usual management (diet, exercise, and insulin), whereas the other received 500 mL of camel milk daily in addition to standard management. A control group of 10 healthy subjects was also assessed. The following parameters were evaluated at baseline and at 4 and 16 weeks: hemoglobin A1c (HbA1c), human C-peptide, lipid profile, serum insulin, anti-insulin antibodies, creatinine clearance, albumin in 24-hour urine, body mass index, and Diabetes Quality of Life score. The following parameters were significantly different between the usual-management group versus the camel milk group after 16 weeks: fasting blood sugar (227.2 +/- 17.7 vs. 98.9 +/- 16.2 mg/dL), HbA1c (9.59 +/- 2.05[%] vs. 7.16 +/- 1.84[%]), serum anti-insulin antibodies (26.20 +/- 7.69 vs. 20.92 +/- 5.45 microU/mL), urinary albumin excretion (25.17 +/- 5.43 vs. 14.54 +/- 5.62 mg/dL/24 hours), daily insulin dose (48.1 +/- 6.95 vs. 23 +/- 4.05 units), and body mass index (18.43 +/- 3.59 vs. 24.3 +/- 2.95 kg/m(2)). Most notably, C-peptide levels were markedly higher in the camel milk group (0.28 +/- 0.6 vs. 2.30 +/- 0.51 pmol/mL). These results suggest that, as an adjunct to standard management, daily ingestion of camel milk can aid metabolic control in young type 1 diabetics, at least in part by boosting endogenous insulin secretion. Topics: Adolescent; Adult; Albuminuria; Animals; Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Camelus; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Medicine, Traditional; Middle East; Milk; Young Adult | 2009 |
Protective effects of 1-alpha-hydroxyvitamin D3 on residual beta-cell function in patients with adult-onset latent autoimmune diabetes (LADA).
Previous in vitro and in vivo studies have demonstrated that vitamin D could prevent pancreatic beta-cell destruction and reduce the incidence of autoimmune diabetes. In children with type 1 diabetes, vitamin D treatment produces moderate protective effects on residual beta-cell function and has proven to be safe. Therefore, we hypothesized that vitamin D might have protective effects on beta-cell function in patients with latent autoimmune diabetes in adults (LADA), a form of slowly progressive autoimmune type 1 diabetes.. Thirty-five patients with LADA were randomly assigned to receive subcutaneous insulin alone (n = 18) or insulin plus 1-alpha-hydroxyvitamin D3 (1-alpha(OH)D3; 0.5 microg per day) (n = 17) for 1 year. Plasma C-peptide levels in fasting state (FCP) and 2 h after 75-g glucose load (PCP) were measured every 6 months with radioimmunoassay.. Both FCP and PCP levels stayed steady in the insulin plus 1-alpha(OH)D3 group, while FCP decreased in insulin-alone group (P = 0.006) during the 12-month intervention. Seventy percent of patients treated with 1-alpha(OH)D3 maintained or increased their FCP concentrations after 1 year of treatment, while only 22% of patients treated with insulin alone maintained stable FCP levels (P < 0.01). Further analysis on LADA subgroups with different durations of diabetes demonstrated that islet beta-cell function was better preserved (as reflected by significantly higher FCP and PCP levels) in the 1-alpha(OH)D3 plus insulin group only in patients with diabetes duration no longer than 1 year. No severe side effects were observed in any group.. Our data suggest that 1-alpha(OH)D3 plus insulin therapy can preserve pancreatic beta-cell function in patients with LADA. Topics: Adult; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Drug Combinations; Female; Humans; Hydroxycholecalciferols; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Longitudinal Studies; Male; Middle Aged; Prospective Studies; Treatment Outcome | 2009 |
Effect of ingested interferon-alpha on beta-cell function in children with new-onset type 1 diabetes.
To evaluate the safety and efficacy of ingested human recombinant interferon-alpha (hrIFN-alpha) for preservation of beta-cell function in young patients with recent-onset type 1 diabetes.. Subjects aged 3-25 years in whom type 1 diabetes was diagnosed within 6 weeks of enrollment were randomly assigned to receive ingested hrIFN-alpha at 5,000 or 30,000 units or placebo once daily for 1 year. The primary outcome was change in C-peptide secretion after a mixed meal.. Individuals in the placebo group (n = 30) lost 56 +/- 29% of their C-peptide secretion from 0 to 12 months, expressed as area under the curve (AUC) in response to a mixed meal. In contrast, children treated with hrIFN-alpha lost 29 +/- 54 and 48 +/- 35% (for 5,000 [n = 27] and 30,000 units [n = 31], respectively, P = 0.028, ANOVA adjusted for age, baseline C-peptide AUC, and study site). Bonferroni post hoc analyses for placebo versus 5,000 units and placebo versus 30,000 units demonstrated that the overall trend was determined by the 5,000-unit treatment group. Adverse events occurred at similar rates in all treatment groups.. Ingested hrIFN-alpha was safe at the doses used. Patients in the 5,000-unit hrIFN-alpha treatment group maintained more beta-cell function 1 year after study enrollment than individuals in the placebo group, whereas this effect was not observed in patients who received 30,000 units hrIFN-alpha. Further studies of low-dose ingested hrIFN-alpha in new-onset type 1 diabetes are needed to confirm this effect. Topics: Administration, Oral; Adolescent; Adult; Antibodies, Antinuclear; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Double-Blind Method; Eating; Humans; Immunologic Factors; Insulin-Secreting Cells; Interferon-alpha; Placebos; Young Adult | 2009 |
Effects of therapy in type 1 and type 2 diabetes mellitus with a peptide derived from islet neogenesis associated protein (INGAP).
Islet neogenesis associated protein (INGAP) has beta cell regenerating effects in experimental models.. Subjects with T1DM (N = 63) and T2DM (N = 126) received 300 or 600 mg/day of INGAP peptide in a 90 day, randomized, double-blind, placebo-controlled trial.. In T1DM, on-treatment Arginine-stimulated C-peptide (AUC(0-30)) significantly increased from baseline in the 600 mg group (p = 0.0058 versus placebo); no significant changes were seen in the 300 mg group. In T2DM, stimulated C-peptide was significantly better preserved in the 600 mg group compared to placebo at day 120, 30 days after washout (p = 0.031 versus placebo), but did not reach statistical significance during treatment or in the 300 mg group. In T2DM, A1C decreased significantly more in the 600 mg group compared to placebo at day 90 (-0.94% versus -0.47%, respectively, p = 0.009) and day 120, 30 days after washout (-0.73% versus -0.24%, respectively, p = 0.013). This was accompanied by significant reductions in mean glucose. No difference from placebo was detected in the 300 mg group or in T1DM. Injection site reactions were the most common adverse event, occurring in 8 (36%) of placebo, 19 (90%) of 300 mg, and 15 (75%) of 600 mg groups (T1DM) and 14 (33%) of placebo, 27 (64%) of 300 mg, and 29 (69%) of 600 mg groups (T2DM).. INGAP peptide increases C-peptide secretion in T1DM and improves glycaemic control in T2DM. Longer-term exposure, more frequent dosing, better tolerated formulations or combination with other therapies may be necessary to achieve optimal clinical response. Topics: Adolescent; Adult; Aged; Analysis of Variance; Antigens, Neoplasm; Area Under Curve; Arginine; Biomarkers, Tumor; Blood Glucose; Body Mass Index; C-Peptide; Cytokines; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Double-Blind Method; Fasting; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Insulin-Secreting Cells; Lectins, C-Type; Male; Middle Aged; Pancreatitis-Associated Proteins; Peptide Fragments; Proinsulin; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Regeneration; Treatment Outcome; Young Adult | 2009 |
Primary graft function, metabolic control, and graft survival after islet transplantation.
OBJECTIVE To investigate the influence of primary graft function (PGF) on graft survival and metabolic control after islet transplantation with the Edmonton protocol. RESEARCH DESIGN AND METHODS A total of 14 consecutive patients with brittle type 1 diabetes were enrolled in this phase 2 study and received median 12,479 islet equivalents per kilogram of body weight (interquartile range 11,072-15,755) in two or three sequential infusions within 67 days (44-95). PGF was estimated 1 month after the last infusion by the beta-score, a previously validated index (range 0-8) based on insulin or oral treatment requirements, plasma C-peptide, blood glucose, and A1C. Primary outcome was graft survival, defined as insulin independence with A1C < or =6.5%. RESULTS All patients gained insulin independence within 12 days (6-23) after the last infusion. PGF was optimal (beta-score > or =7) in nine patients and suboptimal (beta-score < or =6) in five. At last follow-up, 3.3 years (2.8-4.0) after islet transplantation, eight patients (57%) remained insulin independent with A1C < or =6.5%, including seven patients with optimal PGF (78%) and one with suboptimal PGF (20%) (P = 0.01, log-rank test). Graft survival was not significantly influenced by HLA mismatches or by preexisting islet autoantibodies. A1C, mean glucose, glucose variability (assessed with continuous glucose monitoring system), and glucose tolerance (using an oral glucose tolerance test) were markedly improved when compared with baseline values and were significantly lower in patients with optimal PGF than in those with suboptimal PGF. CONCLUSIONS Optimal PGF was associated with prolonged graft survival and better metabolic control after islet transplantation. This early outcome may represent a valuable end point in future clinical trials. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Portal Vein; Tacrolimus; Treatment Outcome | 2009 |
Insulin treatment in IA-2A-positive relatives of type 1 diabetic patients.
We examined whether parenteral regular insulin can prevent diabetes in IA-2 antibody-positive (IA-2A+) relatives of type 1 diabetic patients, using a trial protocol that differed substantially from that of the Diabetes Prevention Trial-1.. Twenty-five IA-2A+ relatives received regular human insulin twice a day for 36 months, during which time they were followed (median [interquartile range; IQR]: 47 [19-66] months) for glucose tolerance, HbA(1c) and islet autoantibodies, together with 25 IA-2A+ relatives (observation/control group) who fulfilled the same inclusion criteria, but were observed for 52 [27-67] months (P=0.58).. Twelve (48%) insulin-treated relatives and 15 (60%) relatives in the control group developed diabetes. There was no difference in diabetes-free survival between the two groups (P=0.97). Five-year progression (95% confidence interval) was 44% (25-69) in the insulin-treated group and 49% (29-70) in the observation group. At inclusion, progressors tended to have a higher pro-insulin/C-peptide ratio than non-progressors when measured 2 hours after a standardized glucose load (median [IQR]: 2.7% [1.8-4.3] vs. 1.6% [1.1-2.1]; P=0.01). No major hypoglycaemic episodes or significant increases in body mass index or diabetes autoantibodies were observed.. Prophylactic injections of regular human insulin were well tolerated, but failed to prevent type 1 diabetes onset in IA-2A+ relatives. Topics: Adolescent; Adult; Autoantibodies; Belgium; Body Mass Index; C-Peptide; Child; Confidence Intervals; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Genotype; Glucose Intolerance; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hyperglycemia; Insulin; Male; Pedigree; Proinsulin; Time Factors; Young Adult | 2009 |
No effect of the altered peptide ligand NBI-6024 on beta-cell residual function and insulin needs in new-onset type 1 diabetes.
This randomized, four-arm, placebo-controlled, dose-ranging phase 2 trial was conducted to determine whether repeated subcutaneous injections of the altered peptide ligand, NBI-6024, designed to inhibit autoreactive T-cells, improves beta-cell function in patients with recently diagnosed type 1 diabetes.. A total of 188 patients, aged 10-35 years, with recently diagnosed type 1 diabetes were randomly assigned for a treatment consisting of the subcutaneous administration of placebo or 1, 0.5, or 0.1 mg NBI-6024 at baseline, weeks 2 and 4, and then monthly until month 24. Fasting, peak, and area under the curve (AUC) C-peptide concentrations during a 2-h mixed-meal tolerance test were measured at 3-month intervals during treatment. Immune function parameters (islet antibodies and CD4 and CD8 T-cells) were also studied.. The mean peak C-peptide concentration at 24 months after study entry showed no significant difference between the groups treated with 0.1 mg (0.59 pmol/ml), 0.5 mg (0.57 pmol/ml), and 1.0 mg NBI-6024 (0.48 pmol/ml) and the placebo group (0.54 pmol/ml). Fasting, stimulated peak, and AUC C-peptide concentrations declined linearly in all groups by approximately 60% over the 24-month treatment period. The average daily insulin needs at month 24 were also comparable between the four groups. No treatment-related changes in islet antibodies and T cell numbers were observed.. Treatment with altered peptide ligand NBI-6024 at repeated doses of 0.1, 0.5, or 1.0 mg did not improve or maintain beta-cell function. Topics: Adolescent; Adult; C-Peptide; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Electrocardiography; Female; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Patient Selection; Peptide Fragments; Placebos; Young Adult | 2009 |
Rituximab, B-lymphocyte depletion, and preservation of beta-cell function.
The immunopathogenesis of type 1 diabetes mellitus is associated with T-lymphocyte autoimmunity. However, there is growing evidence that B lymphocytes play a role in many T-lymphocyte-mediated diseases. It is possible to achieve selective depletion of B lymphocytes with rituximab, an anti-CD20 monoclonal antibody. This phase 2 study evaluated the role of B-lymphocyte depletion in patients with type 1 diabetes.. We conducted a randomized, double-blind study in which 87 patients between 8 and 40 years of age who had newly diagnosed type 1 diabetes were assigned to receive infusions of rituximab or placebo on days 1, 8, 15, and 22 of the study. The primary outcome, assessed 1 year after the first infusion, was the geometric mean area under the curve (AUC) for the serum C-peptide level during the first 2 hours of a mixed-meal tolerance test. Secondary outcomes included safety and changes in the glycated hemoglobin level and insulin dose.. At 1 year, the mean AUC for the level of C peptide was significantly higher in the rituximab group than in the placebo group. The rituximab group also had significantly lower levels of glycated hemoglobin and required less insulin. Between 3 months and 12 months, the rate of decline in C-peptide levels in the rituximab group was significantly less than that in the placebo group. CD19+ B lymphocytes were depleted in patients in the rituximab group, but levels increased to 69% of baseline values at 12 months. More patients in the rituximab group than in the placebo group had adverse events, mostly grade 1 or grade 2, after the first infusion. The reactions appeared to be minimal with subsequent infusions. There was no increase in infections or neutropenia with rituximab.. A four-dose course of rituximab partially preserved beta-cell function over a period of 1 year in patients with type 1 diabetes. The finding that B lymphocytes contribute to the pathogenesis of type 1 diabetes may open a new pathway for exploration in the treatment of patients with this condition. (ClinicalTrials.gov number, NCT00279305.) Topics: Adolescent; Adult; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Area Under Curve; B-Lymphocytes; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Immunoglobulin M; Immunologic Factors; Insulin-Secreting Cells; Male; Rituximab; Young Adult | 2009 |
Long-term metabolic and hormonal effects of exenatide on islet transplant recipients with allograft dysfunction.
The initial success of islet transplantation (ITx) is followed by graft dysfunction (GDF) and insulin reintroduction. Exenatide, a GLP-1 agonist, increases insulin and decreases glucagon secretion and has potential for beta-cell regeneration. To improve functional islet mass, exenatide treatment was given to ITx recipients with GDF. The objective of this study was to assess metabolic and hormonal effects of exenatide in GDF. In this prospective, single-arm, nonrandomized study, 11 type 1 diabetes recipients of ITx with GDF had HbA1c, weight, insulin requirements, and 5-h mixed meal tolerance test (MMTT; with/without exenatide given before test) at baseline, 3, 6, and 12 months after initiating exenatide treatment. Baseline MMTT showed postprandial hyperglycemia and hyperglucagonemia. Daily exenatide treatment resulted in improved glucose, increased amylin/insulin ratio, and decreased proinsulin/insulin ratio as assessed by MMTT. Glucagon responses remained unchanged. Exenatide administration 1 h before MMTT showed decreased glucagon and glucose at 0 min and attenuation in their postprandial rise. Time-to-peak glucose was delayed, followed by insulin, proinsulin, amylin, and C-peptide, indicating glucose-driven insulin secretion. Five subjects completed 12-month follow-up. Glucose and glucagon suppression responses after MMTT with exenatide were no longer observed. Retrospective 3-month analysis of these subjects revealed higher and sustained glucagon levels that did not suppress as profoundly with exenatide administration, associated with higher glucose levels and increased C-peptide responses. In conclusion, Exenatide suppresses the abnormal postprandial hyperglucagonemia and hyperglycemia observed in GDF. Changes in amylin and proinsulin secretion may reflect more efficient insulin processing. Different degrees of responsiveness to exenatide were identified. These may help guide the clinical management of ITx recipients. Topics: Adult; Amyloid; Area Under Curve; C-Peptide; Demography; Diabetes Mellitus, Type 1; Exenatide; Female; Glucagon; Glucose; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin Secretion; Islet Amyloid Polypeptide; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Peptides; Primary Graft Dysfunction; Prospective Studies; Transplantation, Homologous; Venoms | 2009 |
GAD treatment and insulin secretion in recent-onset type 1 diabetes.
The 65-kD isoform of glutamic acid decarboxylase (GAD) is a major autoantigen in patients with type 1 diabetes mellitus. This trial assessed the ability of alum-formulated GAD (GAD-alum) to reverse recent-onset type 1 diabetes in patients 10 to 18 years of age.. We randomly assigned 70 patients with type 1 diabetes who had fasting C-peptide levels above 0.1 nmol per liter (0.3 ng per milliliter) and GAD autoantibodies, recruited within 18 months after receiving the diagnosis of diabetes, to receive subcutaneous injections of 20 microg of GAD-alum (35 patients) or placebo (alum alone, 35 patients) on study days 1 and 30. At day 1 and months 3, 9, 15, 21, and 30, patients underwent a mixed-meal tolerance test to stimulate residual insulin secretion (measured as the C-peptide level). The effect of GAD-alum on the immune system was also studied.. Insulin secretion gradually decreased in both study groups. The study treatment had no significant effect on change in fasting C-peptide level after 15 months (the primary end point). Fasting C-peptide levels declined from baseline levels significantly less over 30 months in the GAD-alum group than in the placebo group (-0.21 vs. -0.27 nmol per liter [-0.62 vs. -0.81 ng per milliliter], P=0.045), as did stimulated secretion measured as the area under the curve (-0.72 vs. -1.02 nmol per liter per 2 hours [-2.20 vs. -3.08 ng per milliliter per 2 hours], P=0.04). No protective effect was seen in patients treated 6 months or more after receiving the diagnosis. Adverse events appeared to be mild and similar in frequency between the two groups. The GAD-alum treatment induced a GAD-specific immune response.. GAD-alum may contribute to the preservation of residual insulin secretion in patients with recent-onset type 1 diabetes, although it did not change the insulin requirement. (ClinicalTrials.gov number, NCT00435981.) Topics: Adolescent; Analysis of Variance; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Immunotherapy; Injections, Subcutaneous; Insulin; Insulin Secretion; Male | 2008 |
Evaluation of beta-cell function in diabetic Taiwanese children using a 6-min glucagon test.
This study evaluates the effects of glucagon 30 mug/kg (maximal 1 mg) on beta-cell function in children by C-peptide determined before and 6 min after intravenous administration. From 1990 to 2005, 118 Taiwanese children with newly diagnosed diabetes mellitus (98 children with type 1 and 20 children with type 2) and 29 normal Taiwanese children were enrolled in this study. Fasting and 6-min post-glucagon C-peptide levels were analyzed. In the pre-pubertal group, the median fasting serum C-peptide levels were 0.2 and 0.8 nmol/l in type 1 diabetes and normal children, respectively. These levels rose to 0.3 and 1.9 nmol/l after glucagon stimulation. In the pubertal group, the median fasting serum C-peptide levels were 0.3, 1.0 and 0.9 nmol/l in type 1 diabetes, type 2 diabetes and normal children, respectively. They rose to 0.4, 2.5 and 2.7 nmol/l after glucagon stimulation. Both fasting and post-glucagon C-peptide levels in type 1 diabetes patients were significantly lower than those of normal children and children with type 2 diabetes. The optimal cut-off values to distinguish type 1 diabetes patients from those with type 2 as determined by the receiving operating characteristic curve were 0.7 and 1.1 nmol/l, respectively. The sensitivities of both C-peptide values were 93%. The post-glucagon C-peptide level was more powerful in distinguishing type 1 diabetes from type 2 diabetes with higher specificity (95% vs. 85%). The 6-min glucagon test is valuable in assessing beta-cell function in children and can help pediatricians in the differential diagnoses of diabetes mellitus in children. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Evaluation Studies as Topic; Female; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Infant; Islets of Langerhans; Male; ROC Curve; Taiwan | 2008 |
A risk score for type 1 diabetes derived from autoantibody-positive participants in the diabetes prevention trial-type 1.
The accurate prediction of type 1 diabetes is essential for appropriately identifying prevention trial participants. Thus, we have developed a risk score for the prediction of type 1 diabetes.. Diabetes Prevention Trial-Type 1 (DPT-1) participants, islet cell autoantibody (ICA)-positive relatives of type 1 diabetic patients (n = 670), were randomly divided into development and validation samples. Risk score values were calculated for the validation sample from development sample model coefficients obtained through forward stepwise proportional hazards regression.. A risk score based on a model including log-BMI, age, log-fasting C-peptide, and postchallenge glucose and C-peptide sums from 2-h oral glucose tolerance tests (OGTTs) was derived from the development sample. The baseline risk score strongly predicted type 1 diabetes in the validation sample (chi(2) = 82.3, P < 0.001). Its strength of prediction was almost the same (chi(2) = 83.3) as a risk score additionally dependent on a decreased first-phase insulin response variable from intravenous glucose tolerance tests (IVGTTs). Biochemical autoantibodies did not contribute significantly to the risk score model. A final type 1 diabetes risk score was then derived from all participants with the same variables as those in the development sample model. The change in the type 1 diabetes risk score from baseline to 1 year was in itself also highly predictive of type 1 diabetes (P < 0.001).. A risk score based on age, BMI, and OGTT indexes, without dependence on IVGTTs or additional autoantibodies, appears to accurately predict type 1 diabetes in ICA-positive relatives. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Middle Aged; Prognosis; Regression Analysis; Risk Factors | 2008 |
Age at diagnosis of type 1 diabetes and the effect of immunomodulatory therapies on residual beta cell function.
Topics: Age of Onset; Aging; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Immunologic Factors; Insulin-Secreting Cells; Male | 2008 |
Comparison of sirolimus alone with sirolimus plus tacrolimus in type 1 diabetic recipients of cultured islet cell grafts.
One year survival of islet cell grafts has been reproducibly achieved under combination immune therapy including tacrolimus (TAC). However, the use of TAC causes beta-cell and renal toxicity. Because sirolimus (SIR) monotherapy was successful in kidney transplantation under antithymocyte globulin (ATG), we undertook a pilot study comparing SIR monotherapy with SIR-TAC combination therapy.. Nonuremic type 1 diabetics received a cultured beta-cell graft under ATG and were randomly assigned to SIR or SIR-TAC-maintenance therapy; a second graft was implanted during posttransplantation month 3 without ATG. The planned number of patients per group (n=10) was reduced to five in view of the observed side effects.. At posttransplant month 6, three SIR-patients had lost graft function and two presented marginal function; among SIR-TAC-patients, there were two early graft failures but three became insulin-independent. These three patients maintained metabolically relevant function (C-peptide >1 ng/ml and coefficient of variation fasting glycemia <25%) for more than 2 years but low-dose insulin therapy was needed from 8, 18, and 26 months posttransplant; this was still the case in two of them after reducing and stopping TAC dose. In both groups, incapacitating adverse events were attributed to sirolimus requiring its discontinuation in 4 of 10 patients; in the 3 patients with pretransplant microalbuminuria, macroalbuminuria developed which resolved when sirolimus was stopped.. SIR monotherapy is not sufficient to suppress rejection after transplantation under ATG, but it can maintain survival of established beta-cell grafts. However, the risk for a SIR-induced proteinuria remains a concern. Topics: Adult; Albuminuria; Autoantibodies; C-Peptide; Cell Transplantation; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Graft Survival; Humans; Immunosuppressive Agents; Islets of Langerhans; Islets of Langerhans Transplantation; Lymphocyte Count; Male; Middle Aged; Postoperative Complications; Sirolimus; Tacrolimus | 2008 |
Insulin intervention in slowly progressive insulin-dependent (type 1) diabetes mellitus.
We tested the hypothesis that insulin therapy rather than sulfonylurea (SU) treatment is preferable to reverse or preserve beta-cell function among patients with slowly progressive insulin-dependent (type 1) diabetes (SPIDDM) or latent autoimmune diabetes in adults.. This multicenter, randomized, nonblinded clinical study screened 4089 non-insulin-dependent diabetic patients for glutamic acid decarboxylase autoantibodies (GADAb). Sixty GADAb-positive non-insulin-requiring diabetic patients with a 5-yr duration or shorter of diabetes were assigned to either the SU group (n = 30) or the insulin group (n = 30). Serum C-peptide responses to annual oral glucose tolerance tests were followed up for a mean of 57 months. The primary endpoint was an insulin-dependent state defined by the sum of serum C-peptide values during the oral glucose tolerance test (SigmaC-peptide) less than 4 ng/ml (1.32 nmol/liter).. The progression rate to an insulin-dependent state in the insulin group (three of 30, 10%) was lower than that in the SU group (13 of 30, 43%; P = 0.003, log-rank). Longitudinal analysis demonstrated that SigmaC-peptide values were better preserved in the insulin group than in the SU group. Multiple regression analysis demonstrated that insulin treatment, a preserved C-peptide response, and a low GADAb titer at entry were independent factors in preventing progression to an insulin-dependent state. Subgroup analysis suggested that insulin intervention was highly effective for SPIDDM patients with high GADAb titers [> or =10 U/ml (180 World Health Organization U/ml)] and preserved beta-cell function [SigmaC-peptide > or = 10 ng/ml (3.31 nmol/liter)] at entry. No severe hypoglycemic episodes occurred during the study.. Insulin intervention to preserve beta-cell function is effective and safe for patients with SPIDDM or latent autoimmune diabetes in adults. Topics: Adult; Aged; Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Glucose Tolerance Test; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Sulfonylurea Compounds; Time Factors | 2008 |
Therapy with the hsp60 peptide DiaPep277 in C-peptide positive type 1 diabetes patients.
Type 1 diabetes results from a T-cell mediated autoimmune destruction of insulin-producing pancreatic beta-cells. The 60-kDa heat-shock protein (hsp60) is one of the known target self-antigens. An immunogenic peptide from hsp60, p277, arrested beta-cell destruction and maintained insulin production in newly diabetic non-obese diabetic (NOD) mice. A randomized, double-blind, phase Ib/II study of peptide treatment was undertaken in recent onset type 1 diabetes patients with remaining insulin production.. Forty-eight recent onset type 1 diabetes patients were assigned subcutaneous injections of 0.2, 1.0 or 2.5 mg peptide DiaPep277 (n = 12 per dosage) at entry, and 1, 6 and 12 months, or four placebo injections (n = 12). The primary clinical endpoints were safety and efficacy (glucagon-stimulated C-peptide production at 6 and 12 months); secondary endpoints were HbA1c levels and daily insulin dose adjusted for body weight at 2, 6, 12 and 18 months.. C-peptide levels decreased over time in all groups except the 2.5 mg-treated. The decrease in C-peptide production was less in treated patients versus placebo, mostly in the 2.5 mg group. HbA1c increased significantly in the 1.0 mg group and in the 2.5 mg group at 2 and 18 months, respectively. No differences were seen in daily insulin doses. One patient was withdrawn from the study possibly owing to a treatment-related adverse event.. Multiple DiaPep277 peptide administration seems safe and may have a beneficial effect on C-peptide levels over time, but this finding is not supported by lower HbA1c levels or daily insulin requirement. Further investigation on a larger scale is warranted. Topics: C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunologic Factors; Insulin; Peptide Fragments; Peptides; Time Factors; Treatment Outcome | 2007 |
Effect of heat shock protein peptide DiaPep277 on beta-cell function in paediatric and adult patients with recent-onset diabetes mellitus type 1: two prospective, randomized, double-blind phase II trials.
Aim of this trial was to test whether heat shock protein peptide DiaPep277 treatment in adult and paediatric patients with recent-onset type 1 diabetes (T1D) is safe and whether it can preserve endogenous insulin production.. Two studies were performed in a prospective, multicentre, double-blind, placebo-controlled trial. Fifty adult (study p520, aged 16-44 years) and 49 paediatric patients (study p521, 4-15 years) with recent-onset T1D were treated subcutaneously at four different time points with 0.2 mg or 1.0 mg DiaPep277 versus placebo and followed for 18 months. Adult patients were treated with 0.2 mg, 1.0 mg or 2.5 mg DiaPep277 versus placebo. Stimulated C-peptide served as readout for functional beta-cell-mass.. DiaPep277-treatment was not associated with severe side effects. No differences were found in placebo and DiaPep277 treated groups. In adults, a modest trend towards better maintenance of beta-cell function was observed in the 0.2 mg and 1.0 mg group, while there was significant loss of stimulated C-peptide in the placebo and 2.5 mg group. Paediatric patients with low HLA risk showed stable C-peptide levels until 13 months upon treatment with 1 mg DiaPep277. Despite similar stimulated C-peptide levels at baseline, children exhibited a more pronounced loss of beta-cell function over 18 months than adults (p = 0.0003).. Administration of DiaPep277 seems safe and may have beneficial effects on C-peptide levels over time in some patients with T1D, but this finding was not accompanied by reduced HbA1c or insulin requirement. Studies with more patients and longer follow-up are needed to further study the effect of DiaPep277. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Chaperonin 60; Child; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Glycated Hemoglobin; HLA Antigens; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Peptide Fragments; Peptides | 2007 |
Treatment of new-onset type 1 diabetes with peptide DiaPep277 is safe and associated with preserved beta-cell function: extension of a randomized, double-blind, phase II trial.
Treatment with DiaPep277, a peptide derived from HSP60, has been shown to preserve beta-cell function in non-obese diabetic mouse (NOD) mice and in a trial with newly diagnosed human patients with type 1 diabetes treated over a 10-month period. This article extends the clinical trial observations to a total of 20 months of treatment to determine the safety and the effects of repeated doses of DiaPep277 on endogenous insulin secretion, metabolic control, and exogenous insulin requirements.. Thirty-five male patients (aged 16-58) with a basal C-peptide greater than 0.1 nmol/L were assigned to periodic treatment with DiaPep277 (1 mg) or placebo for a 12-month treatment and 18-month observation protocol, later extended to an additional year of treatment. Stimulated C-peptide, HbA1c, and an exogenous insulin dose were the clinical endpoints.. At 18 months, stimulated C-peptide concentrations had fallen in the placebo group (p = 0.0005) but were maintained in the DiaPep277 group. The need for exogenous insulin was higher in the placebo group than in the DiaPep277 group. Mean HbA1c concentrations were similar in both groups. After extension of the study, patients continuing treatment with DiaPep277 and those switched from placebo to DiaPep277 manifested a trend towards a greater preservation of beta-cell function compared to patients maintained on or switched to placebo. The safety profile of DiaPep277 was similar between the treatment and placebo groups, and no drug-related adverse events occurred.. Periodic treatment of subjects with DiaPep277 over 2 years was safe and associated preservation of endogenous insulin secretion up to 18 months was observed. Topics: Adolescent; Adult; C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Administration Schedule; Drug Therapy, Combination; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Peptide Fragments; Peptides | 2007 |
Heat-shock protein peptide DiaPep277 treatment in children with newly diagnosed type 1 diabetes: a randomised, double-blind phase II study.
Type 1 diabetes mellitus (T1DM) is a T-cell-mediated autoimmune disease that leads to the destruction of insulin-producing beta cells. Treatment with DiaPep277, a peptide derived from heat-shock protein 60 (hsp60), has been found to slow the deterioration of beta-cell function after clinical onset of diabetes in NOD mice and human adults. Our aim was to evaluate the efficacy and safety of DiaPep277 treatment in attenuating beta-cell destruction in children with recent-onset T1DM.. A prospective, randomized, double-blind, phase II design was used. The sample included 30 children (19 males) aged 7-14 years who had been diagnosed with T1DM from 53 to 116 days previously, and had basal C-peptide concentrations above 0.1 nmol/L. The children were randomized to receive subcutaneous injections of 1 mg DiaPep277 (15 patients) or 40 mg mannitol (placebo) at entry and at 1, 6, and 12 months. The duration of follow-up was 18 months. The groups were compared for stimulated C-peptide level, exogenous insulin dose, and HbA1c concentration.. C-peptide levels similarly decreased over time in the DiaPep277- and placebo-treated patients. There was no significant difference in insulin dose or HbA1c concentration between the groups at any time point. No serious drug-related adverse effects were recorded throughout the study period.. One-year treatment with DiaPep277 at a dosage of 1 mg is safe for use and well tolerated in children with recent-onset T1DM. However, it appears to have no beneficial effect in preserving beta-cell function or improving metabolic control. Topics: Adolescent; C-Peptide; Chaperonin 60; Child; Child, Preschool; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Female; Follow-Up Studies; Gastroenteritis; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Male; Peptide Fragments; Peptides; Treatment Outcome | 2007 |
C-Peptide replacement therapy and sensory nerve function in type 1 diabetic neuropathy.
C-peptide replacement in animals results in amelioration of diabetes-induced functional and structural abnormalities in peripheral nerves. The present study was undertaken to examine whether C-peptide administration to patients with type 1 diabetes and peripheral neuropathy improves sensory nerve function.. This was an exploratory, double-blinded, randomized, and placebo-controlled study with three study groups that was carried out at five centers in Sweden. C-peptide was given as a replacement dose (1.5 mg/day, divided into four subcutaneous doses) or a dose three times higher (4.5 mg/day) during 6 months. Neurological examination and neurophysiological measurements were performed before and after 6 months of treatment with C-peptide or placebo.. The age of the 139 patients who completed the protocol was 44.2 +/- 0.6 (mean +/- SE) years and their duration of diabetes was 30.6 +/- 0.8 years. Clinical neurological impairment (NIA) (score >7 points) of the lower extremities was present in 86% of the patients at baseline. Sensory nerve conduction velocity (SCV) was 2.6 +/- 0.08 SD below body height-corrected normal values at baseline and improved similarly within the two C-peptide groups (P < 0.007). The number of patients responding with a SCV peak potential improvement >1.0 m/s was greater in C-peptide-treated patients than in those receiving placebo (P < 0.03). In the least severely affected patients (SCV < 2.5 SD below normal at baseline, n = 70) SCV improved by 1.0 m/s (P < 0.014 vs. placebo). NIA score and vibration perception both improved within the C-peptide-treated groups (P < 0.011 and P < 0.002). A1C levels (7.6 +/- 0.1% at baseline) decreased slightly but similarly in C-peptide-and placebo-treated patients during the study.. C-peptide treatment for 6 months improves sensory nerve function in early-stage type 1 diabetic neuropathy. Topics: Adult; Age of Onset; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Double-Blind Method; Humans; Middle Aged; Neural Conduction; Neurologic Examination; Patient Selection; Sural Nerve; Sweden | 2007 |
Antibodies to GAD65 and peripheral nerve function in the DCCT.
Antibodies to the smaller isoform of glutamic acid decarboxylase (GAD65Ab) have been linked to the presence of neuropathy in Type 1 diabetes in several small studies. We attempted to confirm this association by measuring GAD65Ab, GAD65Ab epitopes and IA-2Ab in 511 patients who participated in the Diabetes Control and Complications Trial (DCCT). We also tested for correlations between these autoantibodies and C-peptide and glycemic control. We only included patients for whom serum was available from the first 4 years of their illness. The presence or absence of neuropathy was determined by electrophysiological studies, autonomic testing and clinical evaluation at baseline and 5 years into the trial or at close out. Samples from controls (patients without neuropathy at 5 years) were selected for patients who had similar C-peptide responses to a standardized meal at baseline. The GAD65Ab index correlated with HgbA(1c) only in the adult participants and only at baseline. The adults initially in poor control (upper tertile for glycemia) had higher GAD65Ab and lower C-peptides. The GAD65Ab index was not significantly different in patients with confirmed clinical neuropathy at 5 years versus controls matched for C-peptide (.248+/-.03 versus .278+/-.03). Epitope analysis, based on the blocking of conformational epitopes by recombinant Fab, revealed that the binding to multiple epitopes was decreased in the patients with neuropathy. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin-Secreting Cells; Isoenzymes | 2007 |
Autologous nonmyeloablative hematopoietic stem cell transplantation in newly diagnosed type 1 diabetes mellitus.
Type 1 diabetes mellitus (DM) results from a cell-mediated autoimmune attack against pancreatic beta cells. Previous animal and clinical studies suggest that moderate immunosuppression in newly diagnosed type 1 DM can prevent further loss of insulin production and can reduce insulin needs.. To determine the safety and metabolic effects of high-dose immunosuppression followed by autologous nonmyeloablative hematopoietic stem cell transplantation (AHST) in newly diagnosed type 1 DM.. A prospective phase 1/2 study of 15 patients with type 1 DM (aged 14-31 years) diagnosed within the previous 6 weeks by clinical findings and hyperglycemia and confirmed with positive antibodies against glutamic acid decarboxylase. Enrollment was November 2003-July 2006 with observation until February 2007 at the Bone Marrow Transplantation Unit of the School of Medicine of Ribeirão Preto, Ribeirão Preto, Brazil. Patients with previous diabetic ketoacidosis were excluded after the first patient with diabetic ketoacidosis failed to benefit from AHST. Hematopoietic stem cells were mobilized with cyclophosphamide (2.0 g/m2) and granulocyte colony-stimulating factor (10 microg/kg per day) and then collected from peripheral blood by leukapheresis and cryopreserved. The cells were injected intravenously after conditioning with cyclophosphamide (200 mg/kg) and rabbit antithymocyte globulin (4.5 mg/kg).. Morbidity and mortality from transplantation and temporal changes in exogenous insulin requirements (daily dose and duration of usage). Secondary end points: serum levels of hemoglobin A1c, C-peptide levels during the mixed-meal tolerance test, and anti-glutamic acid decarboxylase antibody titers measured before and at different times following AHST.. During a 7- to 36-month follow-up (mean 18.8), 14 patients became insulin-free (1 for 35 months, 4 for at least 21 months, 7 for at least 6 months; and 2 with late response were insulin-free for 1 and 5 months, respectively). Among those, 1 patient resumed insulin use 1 year after AHST. At 6 months after AHST, mean total area under the C-peptide response curve was significantly greater than the pretreatment values, and at 12 and 24 months it did not change. Anti-glutamic acid decarboxylase antibody levels decreased after 6 months and stabilized at 12 and 24 months. Serum levels of hemoglobin A(1c) were maintained at less than 7% in 13 of 14 patients. The only acute severe adverse effect was culture-negative bilateral pneumonia in 1 patient and late endocrine dysfunction (hypothyroidism or hypogonadism) in 2 others. There was no mortality.. High-dose immunosuppression and AHST were performed with acceptable toxicity in a small number of patients with newly diagnosed type 1 DM. With AHST, beta cell function was increased in all but 1 patient and induced prolonged insulin independence in the majority of the patients. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Hematopoietic Stem Cell Mobilization; Hematopoietic Stem Cell Transplantation; Hemoglobins; Humans; Immunosuppression Therapy; Insulin; Male; Prospective Studies; Transplantation Conditioning; Transplantation, Autologous | 2007 |
Fasting c-peptide and insulin-like growth factor-binding protein-1 levels help to distinguish childhood type 1 and type 2 diabetes at diagnosis.
Children with new onset diabetes (n = 175) were evaluated over 12-months. Patients were presumptively diagnosed with type 2 diabetes mellitus (T2DM) (n = 26) based on obesity, a relative with T2DM, the ability to wean from insulin, and absence of glutamic acid decarboxylase-65 (GAD-65) antibodies. We hypothesized that markers of insulinization at diagnosis, including fasting C-peptide and insulin-like growth factor-binding protein (IGFBP)-1, in addition to initial CO(2) levels and urine ketones, would help in distinguishing type 1 diabetes mellitus (T1DM) from T2DM.. Children with T1DM (84 male, 65 female) had a mean age of 8.7 +/- 4.3 yr and a racial background of 78% white, 19% black, and 3% other. In contrast, children with T2DM (13 female, 13 male) had a mean age of 14.2 +/- 3.1 yr with a racial background of 58% black, 27% white, and 15% other. Fasting C-peptide level was 0.38 +/- 0.37 ng/mL in T1DM vs. 2.66 +/- 2.14 ng/mL in T2DM; a C-peptide of 0.85 ng/mL had 83% sensitivity in distinguishing T1DM from T2DM. Fasting IGFBP-1 level was 38.1 +/- 39.1 ng/mL (T1DM) vs. 3.6 +/- 4.5 ng/mL (T2DM); a value of 3.6 ng/dL could distinguish the two types of diabetes with 93% sensitivity. Urinary ketones were found in 79% of children with T1DM compared with 56% of those with T2DM, and the magnitude was associated with type of diabetes. Initial CO(2) level for T1DM was 17.9 +/- 6.9 mmol/L vs. 22.7 +/- 5.7 mmol/L for T2DM; a value of 21.5 mmol/L could distinguish the two types of diabetes with 83% sensitivity.. In addition to obesity, family history of T2DM, and absence of GAD-65 antibodies, children with new-onset T2DM may be distinguished from those with T1DM by a combination of biochemical parameters (C-peptide, IGFBP-1, CO(2), and urine ketones). Topics: Adolescent; Biomarkers; C-Peptide; Carbon Dioxide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Humans; Insulin-Like Growth Factor Binding Protein 1; Ketones; Male; Obesity | 2007 |
Acute effects of C-peptide on gastric emptying in longstanding type 1 diabetes.
Gastric emptying (GE) of a solid (100 g beef) and liquid (150 ml 10 % dextrose) meal was measured in eight patients with type 1 diabetes during intravenous infusion of C-peptide (6 pmol/kg/ min) or isotonic saline. C-peptide had no effect on either solid or liquid GE. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gastric Emptying; Humans; Male; Middle Aged; Time Factors | 2006 |
Patterns of metabolic progression to type 1 diabetes in the Diabetes Prevention Trial-Type 1.
There is little information regarding the pattern of metabolic deterioration before the onset of type 1 diabetes. The goal of this study was to utilize data from the Diabetes Prevention Trial-Type 1 (DPT-1) to obtain a picture of the metabolic progression to type 1 diabetes over a period of approximately 2.5 years before its diagnosis.. Fifty-four DPT-1 participants (22 in the parenteral trial and 32 in the oral trial) were studied. All had oral glucose tolerance tests (OGTTs) at 6-month intervals from approximately 30 to 6 months before diagnosis. The vast majority also had OGTTs at diagnosis. Changes in OGTT glucose and C-peptide indexes from 30 to 6 months before diagnosis were examined by calculating slopes of the indexes for each individual over that time period. Changes from 6 months before diagnosis to diagnosis were examined by paired comparisons of the OGTT metabolic indexes between the time points.. Glucose levels increased gradually from 30 to 6 months before diagnosis in both the parenteral and oral groups (P < 0.001 for all indexes). Area under the curve (AUC) C-peptide (P < 0.05) and AUC C-peptide-to-AUC glucose ratio (P < 0.001) values decreased in the oral group; peak C-peptide-to-2-h glucose ratio values decreased in both groups (P < 0.001). In participants who also had OGTTs at diagnosis, AUC C-peptide (parenteral group, P < 0.05) and peak C-peptide (oral group, P < 0.05) values decreased from the last 6 months before diagnosis; stimulated C-peptide-to-glucose ratio values decreased in both groups (P < 0.001). Conversely, fasting C-peptide levels increased in both groups (oral group, P < 0.01). Fasting C-peptide-to-fasting glucose ratio values remained constant throughout the 30-month follow-up.. These data indicate that over a period of at least 2 years, glucose tolerance gradually deteriorates as stimulated C-peptide levels slowly decline in a substantial number of individuals who develop type 1 diabetes. However, fasting C-peptide levels are maintained, even at diagnosis. Topics: Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Glucose Tolerance Test; Humans; Insulin-Secreting Cells; Prediabetic State | 2006 |
C-peptide does not affect ocular blood flow in patients with type 1 diabetes.
The aim of the present study was to investigate the effect of intravenous C-peptide infusion on ocular blood flow in patients with type 1 diabetes under euglycemic conditions.. The study was performed in a randomized, placebo-controlled, double-masked, two-way, crossover design in 10 type 1 diabetic patients. C-peptide was intravenously administered at two different dosages (dosage 1: 25 pmol . kg(-1) . min(-1) bolus followed by 5 pmol . kg(-1) . min(-1) continuous infusion; dosage 2: six times higher than dosage 1), each for 60 min. Physiologic saline solution was used as a control for C-peptide on a different study day. On both study days, euglycemic clamps were performed. To assess retinal blood flow, laser Doppler velocimetry (blood flow velocities) and retinal vessel analyzer (vessels diameters) measurements were performed. Laser interferometric measurements of fundus pulsation were used to assess pulsatile choroidal blood flow. Blood velocities in the ophthalmic artery were measured using color Doppler imaging.. Eight patients (two female and six male) completed the study according to the protocol and without adverse events. One patient developed an anaphylactic reaction to C-peptide, which resolved without sequelae. The following results originate from the remaining eight subjects. Systemic hemodynamic parameters remained stable during both study days. Infusion of C-peptide did not affect any ocular hemodynamic parameter.. The data of the present study indicate that exogenous C-peptide exerts no effect on ocular hemodynamic parameters in type 1 diabetic patients under euglycemic conditions. The maximum detectable change in these parameters was <25%. Topics: Adult; Blood Flow Velocity; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Eye; Female; Humans; Infusions, Intravenous; Laser-Doppler Flowmetry; Male; Ophthalmic Artery; Retinal Vessels | 2006 |
International trial of the Edmonton protocol for islet transplantation.
Islet transplantation offers the potential to improve glycemic control in a subgroup of patients with type 1 diabetes mellitus who are disabled by refractory hypoglycemia. We conducted an international, multicenter trial to explore the feasibility and reproducibility of islet transplantation with the use of a single common protocol (the Edmonton protocol).. We enrolled 36 subjects with type 1 diabetes mellitus, who underwent islet transplantation at nine international sites. Islets were prepared from pancreases of deceased donors and were transplanted within 2 hours after purification, without culture. The primary end point was defined as insulin independence with adequate glycemic control 1 year after the final transplantation.. Of the 36 subjects, 16 (44%) met the primary end point, 10 (28%) had partial function, and 10 (28%) had complete graft loss 1 year after the final transplantation. A total of 21 subjects (58%) attained insulin independence with good glycemic control at any point throughout the trial. Of these subjects, 16 (76%) required insulin again at 2 years; 5 of the 16 subjects who reached the primary end point (31%) remained insulin-independent at 2 years.. Islet transplantation with the use of the Edmonton protocol can successfully restore long-term endogenous insulin production and glycemic stability in subjects with type 1 diabetes mellitus and unstable control, but insulin independence is usually not sustainable. Persistent islet function even without insulin independence provides both protection from severe hypoglycemia and improved levels of glycated hemoglobin. (ClinicalTrials.gov number, NCT00014911 [ClinicalTrials.gov].). Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Feasibility Studies; Follow-Up Studies; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Infusions, Intravenous; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Isoantibodies; Middle Aged; Opportunistic Infections; Portal Vein; Reproducibility of Results; Transplantation Conditioning | 2006 |
DiaPep277 preserves endogenous insulin production by immunomodulation in type 1 diabetes.
DiaPep277 is an immunomodulatory peptide that arrests beta cell destruction in mouse models of type 1 diabetes mellitus (T1DM). This article extends an original pilot observation to two studies of 61 patients (age > 16 years), diagnosed with T1DM within 6 months, and with measurable beta cell function. Patients were treated with placebo (n = 27) or 1.0 mg DiaPep277 (n = 34). After 13 months, 1.0 mg Dia Pep277 treatment significantly (P = 0.02) preserved beta cell function as compared to the control with a trend for reduced HbA1c. This was achieved without an increase in insulin dose in the DiaPep277 group and with excellent safety. DiaPep277-treated patients also had fewer Th1 DiaPep277-specific T cells. Topics: Amino Acid Sequence; Area Under Curve; C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Molecular Sequence Data; Peptide Fragments; Peptides; Time Factors; Treatment Outcome | 2006 |
Camel milk as an adjunct to insulin therapy improves long-term glycemic control and reduction in doses of insulin in patients with type-1 diabetes A 1 year randomized controlled trial.
Topics: Animals; Blood Glucose; Body Mass Index; C-Peptide; Camelus; Combined Modality Therapy; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Fasting; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Lactation; Milk; Patients; Time Factors; Treatment Outcome | 2005 |
A single course of anti-CD3 monoclonal antibody hOKT3gamma1(Ala-Ala) results in improvement in C-peptide responses and clinical parameters for at least 2 years after onset of type 1 diabetes.
Despite advances in understanding autoimmune diabetes in animal models, there has been little progress in altering the natural course of the human disease, which involves progression to insulin deficiency. Studies with immunosuppressive agents have shown short-term effectiveness, but they have not induced tolerance, and continuous treatment is needed. We studied the effects of hOKT3gamma1(Ala-Ala), a humanized Fc mutated anti-CD3 monoclonal antibody, on the progression of type 1 diabetes in patients with recent-onset disease in a randomized controlled trial. In general, the drug was well tolerated. A single course of treatment, within the first 6 weeks after diagnosis, preserved C-peptide responses to a mixed meal for 1 year after diagnosis (97 +/- 9.6% of response at study entry in drug-treated patients vs. 53 +/- 7.6% in control subjects, P < 0.01), with significant improvement in C-peptide responses to a mixed meal even 2 years after treatment (P < 0.02). The improved C-peptide responses were accompanied by reduced HbA(1c) and insulin requirements. Clinical responses to drug treatment were predicted by an increase in the relative number of CD8(+) T-cells in the peripheral blood after the lymphocyte count recovered 2 weeks after the last dose of drug. We conclude that treatment with the anti-CD3 monoclonal antibody hOKT3gamma1(Ala-Ala) results in improved C-peptide responses and clinical parameters in type 1 diabetes for at least 2 years in the absence of continued immunosuppressive medications. Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Male; Muromonab-CD3; Time Factors | 2005 |
The beneficial effects of pancreas transplant alone on diabetic nephropathy.
Pancreas transplant alone can be effective in significantly improving the quality of life of type 1 diabetic patients, and it can also eliminate acute diabetes complications, such as hypoglycemic and/or hyperglycemic episodes. The effects of pancreas transplant alone on long-term complications of diabetes, including nephropathy, are still not settled. We evaluated whether restoration of long-lasting normoglycemia by pancreas transplant alone might have beneficial action on diabetic nephropathy.. A total of 32 type 1 diabetic patients were evaluated before and 1 year after successful pancreas transplant alone, together with 30 matched nontransplanted type 1 diabetic subjects. Several metabolic and kidney function parameters were measured, including plasma glucose, glycohemoglobin (A1C), C-peptide, plasma lipids, blood pressure, creatinine, creatinine clearance, and urinary protein excretion.. Pancreas transplant alone restored sustained normoglycemia, without exogenous insulin administration, and improved plasma lipid levels. Blood pressure decreased significantly. Creatinine concentrations and clearances did not differ before and after transplantation. Urinary protein excretion decreased significantly after pancreas transplant alone, with four microalbuminuric and three macroalbuminuric patients who became normoalbuminuric. None of these changes occurred in the nontransplanted group.. Successful pancreas transplant alone, through restoration of sustained normoglycemia, improves diabetic nephropathy in type 1 diabetic patients. Topics: Adult; Anticholesteremic Agents; Antihypertensive Agents; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Humans; Male; Pancreas Transplantation; Proteinuria; Time Factors; Triglycerides | 2005 |
Islet transplantation is associated with an improvement of cardiovascular function in type 1 diabetic kidney transplant patients.
Cardiovascular mortality and morbidity are major problems in type 1 diabetic patients with end-stage renal disease (ESRD). The aim of this study was to determine whether islet transplantation can improve cardiovascular function in these patients.. We assessed various markers of cardiac function at baseline and 3 years later in a population of 42 type 1 diabetic patients with ESRD who received a kidney transplant. Seventeen patients then received an islet transplant that had persistent function as defined by long-term C-peptide secretion (kidney-islet group). Twenty-five patients did not receive a functioning islet transplant (kidney-only group).. GHb levels were similar in the two groups, whereas the exogenous insulin requirement was lower in the kidney-islet group with persistent C-peptide secretion. Overall, cardiovascular parameters improved in the kidney-islet group, but not in the kidney-only group, with an improvement of ejection fraction (from 68.2 +/- 3.5% at baseline to 74.9 +/- 2.1% at 3 years posttransplantation, P < 0.05) and peak filling rate in end-diastolic volume (EDV) per second (from 3.87 +/- 0.25 to 4.20 +/- 0.37 EDV/s, P < 0.05). Time to peak filling rate remained stable in the kidney-islet group but worsened in the kidney-only group (P < 0.05). The kidney-islet group also showed a reduction of both QT dispersion (53.5 +/- 4.9 to 44.6 +/- 2.9 ms, P < 0.05) and corrected QT (QTc) dispersion (67.3 +/- 8.3 to 57.2 +/- 4.6 ms, P < 0.05) with higher erythrocytes Na(+)-K(+)-ATPase activity. In the kidney-islet group only, both atrial natriuretic peptide and brain natriuretic peptide levels decreased during the follow-up, with a stabilization of intima-media thickness.. Our study showed that type 1 diabetic ESRD patients receiving a kidney transplant and a functioning islet transplant showed an improvement of cardiovascular function for up to 3 years of follow-up compared with the kidney-only group, who experienced an early failure of the islet graft or did not receive an islet graft. Topics: Atrial Natriuretic Factor; C-Peptide; Cardiovascular Diseases; Cardiovascular Physiological Phenomena; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Erythrocytes; Female; Graft Survival; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Natriuretic Peptide, Brain; Postoperative Complications; Sodium-Potassium-Exchanging ATPase | 2005 |
Insulin needs after CD3-antibody therapy in new-onset type 1 diabetes.
Type 1 diabetes mellitus is a T-cell-mediated autoimmune disease that leads to a major loss of insulin-secreting beta cells. The further decline of beta-cell function after clinical onset might be prevented by treatment with CD3 monoclonal antibodies, as suggested by the results of a phase 1 study. To provide proof of this therapeutic principle at the metabolic level, we initiated a phase 2 placebo-controlled trial with a humanized antibody, an aglycosylated human IgG1 antibody directed against CD3 (ChAglyCD3).. In a multicenter study, 80 patients with new-onset type 1 diabetes were randomly assigned to receive placebo or ChAglyCD3 for six consecutive days. Patients were followed for 18 months, during which their daily insulin needs and residual beta-cell function were assessed according to glucose-clamp-induced C-peptide release before and after the administration of glucagon.. At 6, 12, and 18 months, residual beta-cell function was better maintained with ChAglyCD3 than with placebo. The insulin dose increased in the placebo group but not in the ChAglyCD3 group. This effect of ChAglyCD3 was most pronounced among patients with initial residual beta-cell function at or above the 50th percentile of the 80 patients. In this subgroup, the mean insulin dose at 18 months was 0.22 IU per kilogram of body weight per day with ChAglyCD3, as compared with 0.61 IU per kilogram with placebo (P<0.001). In this subgroup, 12 of 16 patients who received ChAglyCD3 (75 percent) received minimal doses of insulin (< or =0.25 IU per kilogram per day) as compared with none of the 21 patients who received placebo. Administration of ChAglyCD3 was associated with a moderate "flu-like" syndrome and transient symptoms of Epstein-Barr viral mononucleosis.. Short-term treatment with CD3 antibody preserves residual beta-cell function for at least 18 months in patients with recent-onset type 1 diabetes. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; CD3 Complex; Child; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Herpesviridae; Humans; Hypoglycemic Agents; Immunoglobulin G; Insulin; Islets of Langerhans; Male | 2005 |
The effect of rosiglitazone on overweight subjects with type 1 diabetes.
To evaluate the safety and effectiveness of rosiglitazone in the treatment of overweight subjects with type 1 diabetes.. A total of 50 adult type 1 diabetic subjects with a baseline BMI > or =27 kg/m(2) were randomly assigned in a double-blind fashion to take insulin and placebo (n = 25) or insulin and rosiglitazone 4 mg twice daily (n = 25) for a period of 8 months. Insulin regimen and dosage were modified in all subjects to achieve near-normal glycemic control.. Both groups experienced a significant reduction in HbA(1c) (A1C) level (rosiglitazone: 7.9 +/- 1.3 to 6.9 +/- 0.7%, P < 0.0001; placebo: 7.7 +/- 0.8 to 7.0 +/- 0.9%, P = 0.002) and a significant increase in weight (rosiglitazone: 97.2 +/- 11.8 to 100.6 +/- 16.0 kg, P = 0.008; placebo: 96.4 +/- 12.2 to 99.1 +/- 15.0, P = 0.016). Baseline measures of BMI (P = 0.001), total daily insulin dose (P = 0.002), total cholesterol (P = 0.005), HDL cholesterol (P = 0.001), and LDL cholesterol (P = 0.02) were predictors of improvement in A1C level only in the group treated with rosiglitazone. Total daily insulin dose increased in subjects taking placebo (74.0 +/- 33.8 to 82.0 +/- 48.9 units, P < 0.05 baseline vs. week 32), but it decreased slightly in subjects taking rosiglitazone (77.5 +/- 28.6 to 75.3 +/- 33.1 units). Both systolic blood pressure (137.4 +/- 15.6 vs. 128.8 +/- 14.8 mmHg, baseline vs. week 32, P < 0.02) and diastolic blood pressure (87.2 +/- 9.4 vs. 79.4 +/- 7.2 mmHg, P < 0.0001) improved in the group treated with rosiglitazone. The total incidence of hypoglycemia did not differ between groups.. Rosiglitazone in combination with insulin resulted in improved glycemic control and blood pressure without an increase in insulin requirements, compared with insulin- and placebo-treated subjects, whose improved glycemic control required an 11% increase in insulin dose. Weight gain and hypoglycemia were similar in both groups at the end of the study. The greatest effect of rosiglitazone occurred in subjects with more pronounced markers of insulin resistance. Topics: Adult; Blood Glucose; Body Mass Index; Body Size; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Ethnicity; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Obesity; Placebos; Rosiglitazone; Thiazolidinediones; Weight Gain | 2005 |
Use of inhaled insulin in a basal/bolus insulin regimen in type 1 diabetic subjects: a 6-month, randomized, comparative trial.
Despite the demonstrated benefits of glycemic control, patient acceptance of basal/bolus insulin therapy for type 1 diabetes has been slow. We investigated whether a basal/bolus insulin regimen involving rapid-acting, dry powder, inhaled insulin could provide glycemic control comparable with a basal/bolus subcutaneous regimen.. Patients with type 1 diabetes (ages 12-65 years) received twice-daily subcutaneous NPH insulin and were randomized to premeal inhaled insulin (n = 163) or subcutaneous regular insulin (n = 165) for 6 months.. Mean glycosylated hemoglobin (A1C) decreased comparably from baseline in the inhaled and subcutaneous insulin groups (-0.3 and -0.1%, respectively; adjusted difference -0.16% [CI -0.34 to 0.01]), with a similar percentage of subjects achieving A1C <7%. Although 2-h postprandial glucose reductions were comparable between the groups, fasting plasma glucose levels declined more in the inhaled than in the subcutaneous insulin group (adjusted difference -39.5 mg/dl [CI -57.5 to -21.6]). Inhaled insulin was associated with a lower overall hypoglycemia rate but higher severe hypoglycemia rate. The overall hypoglycemia rate (episodes/patient-month) was 9.3 (inhaled) vs. 9.9 (subcutaneous) (risk ratio [RR] 0.94 [CI 0.91-0.97]), and the severe hypoglycemia rate (episodes/100 patient-months) was 6.5 vs. 3.3 (RR 2.00 [CI 1.28-3.12]). Increased insulin antibody serum binding without associated clinical manifestations occurred in the inhaled insulin group. Pulmonary function between the groups was comparable, except for a decline in carbon monoxide-diffusing capacity in the inhaled insulin group without any clinical correlates.. Inhaled insulin may provide an alternative for the management of type 1 diabetes as part of a basal/bolus strategy in patients who are unwilling or unable to use preprandial insulin injections. Topics: Administration, Inhalation; Adolescent; Adult; Aged; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Injections, Subcutaneous; Insulin; Male; Middle Aged; Respiratory Function Tests | 2005 |
Lack of effect of intermittently administered sodium fusidate in patients with newly diagnosed type 1 diabetes mellitus: the FUSIDM trial.
We evaluated in a double-blind study the effect of early treatment with the immunomodulatory drug fusidin in patients with newly diagnosed type 1 diabetes mellitus.. Twenty-eight adults with newly diagnosed type 1 diabetes were included in the study. The patients were randomly assigned (computer-generated random number sequence) to two experimental groups. Patients allocated to the fusidin (FUS) group (n=15) received sodium fusidate (fusidin; 500 mg orally three times daily for 4 weeks). Subsequently the drug was given at the same dose and scheduled for two consecutive weeks a month followed by 2 weeks a month without the drug for 20 weeks. Subjects allocated to the placebo (PCB) group (n=13) received placebo according to the same schedule and conditions described for sodium fusidate in the FUS group. All patients received a diet adjusted to their age and BMI, and intensive insulin therapy.. There were no statistically significant differences between the FUS and PCB groups in beta cell function, evaluated by basal and glucagon-stimulated C-peptide values during the follow-up (24 and 48 weeks). There was also no difference between the two groups in insulin requirement after 48 weeks (0.4+/-0.2 and 0.4+/-0.2 U/kg body weight for the FUS and PCB groups, respectively). Antibody titres, including insulin autoantibodies, were similar in the two groups during the follow-up.. Early treatment of newly diagnosed type 1 diabetes patients with intermittently administered fusidin failed to influence the natural course of the disease. Topics: Adult; Anti-Bacterial Agents; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Follow-Up Studies; Fusidic Acid; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunologic Factors; Insulin; Islets of Langerhans; Male | 2005 |
Islet transplantation in type 1 diabetes mellitus using cultured islets and steroid-free immunosuppression: Miami experience.
Following the success obtained with transplantation of fresh human islets under steroid-free immunosuppression, this trial evaluated the transplantation of islets that had undergone a period of in vitro culture and the potential of tumor necrosis factor (TNF-alpha) blockade to improve islet engraftment. Subjects included 16 patients with type 1 diabetes mellitus (T1DM); half were randomly assigned to receive Infliximab immediately preceding initial infusion. Immunosuppression consisted of daclizumab induction and sirolimus/tacrolimus maintenance. Out of 16 subjects 14 achieved insulin independence with one or two islet infusions; adverse events precluded completion in two. Without supplemental infusions, 11/14 (79%) subjects were insulin independent at 1 year, 6/14 (43%) at 18 months; these same subjects remain insulin independent at 33+/-6 months. While on immunosuppression, all patients maintained graft function. Out of 14 patients, 8 suffered chronic partial graft loss, likely immunological in nature, 5 of these received supplemental infusions. Currently, 11 subjects remain on immunosuppression, 8 (73%) are insulin independent, two with supplemental infusions. Insulin independent subjects demonstrated normalization of HbA1c, fructosamine and Mean Amplitude of Glycemic Excursions (MAGE) values. No clinical benefit of infliximab was identified. These results demonstrate that transplantation of cultured human islet allografts results in reproducible insulin independence in all subjects under this immunosuppressive regimen, comparable to that of freshly transplanted islets (Edmonton protocol). Topics: Adult; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Blood Glucose; C-Peptide; Daclizumab; Diabetes Mellitus, Type 1; Female; Graft Survival; Humans; Immunoglobulin G; Immunosuppressive Agents; Infliximab; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Prospective Studies; Sirolimus; Tacrolimus; Tissue Culture Techniques; Tumor Necrosis Factors | 2005 |
Xenotransplantation of porcine neonatal islets of Langerhans and Sertoli cells: a 4-year study.
Porcine islets of Langerhans for xenotransplantation into humans have been proposed as a solution to the shortage of human donors. Rejection is one of the main constraints. This study presents the results of a clinical trial using a novel method for transplanting and immunoprotecting porcine islets in type 1 diabetic patients.. A 4-year follow up of a clinical trial involving 12 patients, with no immunosuppressive drugs at any point. Eleven age matched untransplanted diabetics served as controls.. We have developed a procedure for protecting neonatal porcine islets by combining them with Sertoli cells and placing them in a novel subcutaneous autologous collagen-covered device.. In the patients in the treatment group, no complications arose and no porcine endogenous retrovirus infection was detected. Half of the patients showed a significant reduction in insulin requirements compared with both their pre transplant levels and controls, and this reduction was maintained for up to 4 years. Two patients became insulin-independent for several months. Porcine insulin was detected in three patients' sera following glucose stimulation up to 4 years post transplant. Three years post transplant, one of four devices was removed from four patients, and the presence of insulin-positive cells in the transplant was demonstrated by immunohistology in all 4 patients.. Long-term cell survival with concurrent positive effects on metabolic control are possible by this technique. Topics: Adolescent; Animals; Animals, Newborn; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Graft Rejection; Graft Survival; Humans; Immunohistochemistry; Insulin; Islets of Langerhans Transplantation; Male; Sertoli Cells; Specific Pathogen-Free Organisms; Swine; Transplantation, Heterologous | 2005 |
A two year observational study of nicotinamide and intensive insulin therapy in patients with recent onset type 1 diabetes mellitus.
A number of trials have evaluated residual beta-cell function in patients with recent onset type 1 diabetes mellitus (DM1) treated with nicotinamide in addition to intensive insulin therapy (IIT). In most studies, only a slight decline of C-peptide secretion was observed 12 months after diagnosis; however, no data is available on C-peptide secretion and metabolic control in patients continuing nicotinamide and IIT for up to 2 years after diagnosis.. We retrospectively analysed data from 25 patients (mean age 14.7 years +/- 5 SD) with DM1 in whom nicotinamide at a dose of 25 mg/kg b. wt. was added from diagnosis (< 4 weeks) to IIT (three injections of regular insulin at meals + one NPH at bed time) and continued for up to 2 years after diagnosis. Data were also analysed from patients (n = 27) in whom IIT was introduced at diagnosis and who were similarly followed for 2 years. Baseline C-peptide as well as insulin dose and HbA1c levels were evaluated at 12 and 24 months after diagnosis.. In the course of the follow-up, patients on nicotinamide + IIT or IIT alone did not significantly differ in terms of C-peptide secretion (values at 24 months in the two groups were 0.19 +/- 0.24 nM vs 0.19 +/- 0.13 nM, respectively). Insulin requirement (0.6 +/- 0.3 U/kg/day vs 0.7 +/- 0.2 U/kg/day at 24 months, respectively) did not differ between the two groups. However, HbA1c was significantly lower 2 years after diagnosis in patients treated with nicotinamide + IIT (6.09 +/- 0.9% vs 6.98 +/- 0.9%, respectively, p < 0.01). No adverse effects were observed in patients receiving nicotinamide for 2 years.. Implementation of IIT with the addition of nicotinamide at diagnosis continued for 2 years improves metabolic control as assessed by HbA1c. In both nicotinamide and control patients, no decline in C-peptide was detected 2 years after diagnosis, indicating that IIT preserves C-peptide secretion. We conclude that nicotinamide + IIT at diagnosis of DM1 prolonged for up to 2 years can be recommended, but longer follow-up is required to determine whether nicotinamide should be continued beyond this period. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Hypoglycemic Agents; Insulin; Male; Niacinamide; Retrospective Studies | 2005 |
C-peptide improves adenosine-induced myocardial vasodilation in type 1 diabetes patients.
Patients with type 1 (insulin-dependent) diabetes show reduced skeletal muscle blood flow and coronary vasodilatory function despite intensive insulin therapy and good metabolic control. Administration of proinsulin C-peptide increases skeletal muscle blood flow in these patients, but a possible influence of C-peptide on myocardial vasodilatory function in type 1 diabetes has not been investigated. Ten otherwise healthy young male type 1 diabetic patients (Hb A1c 6.6%, range 5.7-7.9%) were studied on two consecutive days during normoinsulinemia and euglycemia in a double-blind, randomized, crossover design, receiving intravenous infusion of C-peptide (5 pmol.kg-1.min-1) for 120 min on one day and saline infusion on the other day. Myocardial blood flow (MBF) was measured at rest and during adenosine administration (140 microg.kg-1.min-1) both before and during the C-peptide or saline infusions by use of positron emission tomography and [15O]H2O administration. Basal MBF was not significantly different in the patients compared with an age-matched control group, but adenosine-induced myocardial vasodilation was 30% lower (P < 0.05) in the patients. During C-peptide administration, adenosine-stimulated MBF increased on average 35% more than during saline infusion (P < 0.02) and reached values similar to those for the healthy controls. Moreover, as evaluated from transthoracal echocardiographic measurements, C-peptide infusion resulted in significant increases in both left ventricular ejection fraction (+5%, P < 0.05) and stroke volume (+7%, P < 0.05). It is concluded that short-term C-peptide infusion in physiological amounts increases the hyperemic MBF and left-ventricular function in type 1 diabetic patients. Topics: Adenosine; Adult; Blood Glucose; Blood Pressure; C-Peptide; Coronary Circulation; Coronary Vessels; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Echocardiography; Heart; Humans; Insulin; Male; Reference Values; Regional Blood Flow; Tomography, Emission-Computed; Vasodilation | 2004 |
The insulin secretagogues glibenclamide and repaglinide do not influence growth hormone secretion in humans but stimulate glucagon secretion during profound insulin deficiency.
In vitro data have recently suggested that sulfonylureas (SUs) enhance GH secretion by modulating the effects of GHRH and somatostatin in pituitary cells. The present study was undertaken to explore in more detail a possible influence of a single dose of SU (glibenclamide) and a non-SU (repaglinide) insulin secretagogue on circulating GH dynamics. Ten C-peptide-negative type 1 diabetic individuals were examined on three occasions in random order. Either glibenclamide (10.5 mg), repaglinide (8 mg), or placebo was administered after overnight normalization of plasma glucose by iv insulin infusion. Subsequently, GH concentrations were measured regularly after stimulation with GHRH (bolus 0.1 micro g/kg) alone and during concomitant infusion with somatostatin (7 ng.kg(-1).min(-1)). Insulin was replaced at baseline levels (0.25 mU.kg(-1).min(-1)) and plasma glucose clamped at 5-6 mmol/liter. Overall, there were no significant statistical differences in GH responses determined as either GH peak concentrations, integrated levels of GH, or secretory burst mass of GH during the experimental protocol. In contrast, plasma glucagon concentrations were significantly increased during glibenclamide and repaglinide exposure. The present experimental design does not support the hypothesis that acute administration of pharmacological doses of the oral antihyperglycemic agents glibenclamide and repaglinide per se enhance GH release in humans. Additionally, this study shows that these potassium channel inhibitors seem to stimulate glucagon secretion in people who have severe intraislet insulin deficiency (e.g. type 1 diabetes). However, extrapolation of our findings to type 2 diabetic individuals should be done with some caution. Topics: Blood Glucose; C-Peptide; Carbamates; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Glucagon; Glucose Clamp Technique; Glyburide; Growth Hormone-Releasing Hormone; Human Growth Hormone; Humans; Hypoglycemic Agents; Insulin; Piperidines; Placebos; Potassium Channel Blockers; Somatostatin | 2004 |
Insulin secretion in type 1 diabetes.
Type 1 diabetes, a chronic autoimmune disease, causes destruction of insulin-producing beta-cells over a period of years. Although many markers of the autoimmune process have been described, none can convincingly predict the rate of disease progression. Moreover, there is relatively little information about changes in insulin secretion in individuals with type 1 diabetes over time. Previous studies document C-peptide at a limited number of time points, often after a nonphysiologic stimulus, and under non-steady-state conditions. Such methods do not provide qualitative information and may not reflect physiologic responses. We have studied qualitative and quantitative insulin secretion to a 4-h mixed meal in 41 patients with newly diagnosed type 1 diabetes and followed the course of this response for 24 months in 20 patients. Newly diagnosed diabetic patients had an average total insulin secretion in response to a mixed meal that was 52% of that in nondiabetic control subjects, considerably higher than has been described previously. In diabetic patients there was a decline of beta-cell function at an average rate of 756 +/- 132 pmol/month to a final value of 28 +/- 8.4% of initial levels after 2 years. There was a significant correlation between the total insulin secretory response and control of glucose, measured by HbA(1c) (P = 0.003). Two persistent patterns of insulin response were seen depending on the peak insulin response following the oral meal. Patients with an early insulin response (i.e., within the first 45 min after ingestion) to a mixed meal, which was also seen in 37 of 38 nondiabetic control subjects, had a significantly accelerated loss of insulin secretion, as compared with those in whom the insulin response occurred after this time (P < 0.05), and significantly greater insulin secretory responses at 18 and 24 months (P < 0.02). These results, which are the first qualitative studies of insulin secretion in type 1 diabetes, indicate that the physiologic metabolic response is greater at diagnosis than has previously been appreciated, and that the qualitative insulin secretory response is an important determinant of the rate of metabolic decompensation from autoimmune destruction. Topics: Adolescent; Adult; Age of Onset; Antibodies, Monoclonal; Area Under Curve; C-Peptide; Child; Diabetes Mellitus, Type 1; Eating; Humans; Insulin; Insulin Secretion; Kinetics; Postprandial Period; Receptor-CD3 Complex, Antigen, T-Cell; Reference Values | 2004 |
A randomized trial of nicotinamide and vitamin E in children with recent onset type 1 diabetes (IMDIAB IX).
Various adjuvant therapies have been introduced along with intensive insulin therapy in patients with recent onset type 1 diabetes. Nicotinamide (NA), administered at diagnosis of the disease, can have beneficial effects on the clinical remission rate, improve metabolic control and preserve or slightly increase beta-cell function, probably by reducing toxicity due to free oxygen radicals. Vitamin E, a known antioxidant, inhibits lipid peroxidation; this can lead to protection of islet beta cells from the combined effects of interleukin 1, tumor necrosis factor and gamma interferon. The aim of the present study was to investigate whether the addition of vitamin E to NA could improve metabolic control and the residual beta-cell function, as measured by C-peptide secretion, in children and adolescents with recent onset type 1 diabetes; patients were followed-up for 2 years after diagnosis.. Recent onset type 1 diabetes patients (n=64, mean age 8.8 years) were recruited by participating centres of the IMDIAB group. Thirty-two patients were randomized to NA (25 mg/kg body weight) plus vitamin E (15 mg/kg body weight); 32 patients acted as controls and received NA only at the same dose as above. Intensive insulin therapy was applied to both treatment groups.. There were three drop outs during the 2-year follow-up period. Overall, patients assigned to the NA+vitamin E group or the NA group did not significantly differ in terms of glycated hemoglobin (HbA1c) levels, insulin requirement or baseline C-peptide secretion. Patients diagnosed at an age of less than 9 years showed significantly reduced C-peptide levels compared with those aged over 9 years at diagnosis and at the 2-year follow-up but there were no differences between the NA and NA+vitamin E treated groups. However at 6 months, patients over 9 years of age treated with NA+vitamin E showed significantly higher C-peptide compared with the NA group (P<0.003). In both age groups and in the different treatment groups, C-peptide levels found at diagnosis were preserved 2 years later.. The use of NA alone, or in combination with vitamin E, along with intensive insulin therapy is able to preserve baseline C-peptide secretion for up to 2 years after diagnosis. This finding is of particular interest for pre-pubertal children with type 1 diabetes and has never been reported before. Topics: Adolescent; Aging; Antioxidants; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Humans; Hypoglycemic Agents; Insulin; Niacinamide; Vitamin E | 2004 |
Preservation of C-peptide secretion in subjects at high risk of developing type 1 diabetes mellitus--a new surrogate measure of non-progression?
Individuals at high risk of developing type 1 diabetes mellitus can be identified using immunologic, genetic, and metabolic parameters. In the Diabetes Prevention Trial-1 (DPT-1), annual intravenous infusions of low doses of regular insulin, together with daily subcutaneous injection of a single low dose of Ultralente insulin at nighttime, failed to prevent or delay the onset of type 1 diabetes in high-risk non-diabetic relatives. In our study, we attempted to achieve beta-cell rest by administering higher doses of neutral protamine Hagedorn (NPH) insulin twice daily to high-risk non-diabetic subjects in an effort to prevent or delay the onset of the disease. The maximum tolerable dose was given with the dose reduced for any hypoglycemia (mean dose 0.33 +/- 0.15; range 0.09-0.66 units/kg/d). We treated 26 subjects who were confirmed to have islet cell antibodies (ICAs) and a low first-phase insulin response (FPIR) to intravenous glucose. Fourteen had normal glucose tolerance and 12 impaired glucose tolerance (IGT). The median duration of follow-up was 5.5 yr. Diabetes occurred in 10 of 12 subjects with IGT and five of 14 subjects with normal glucose tolerance. The cumulative incidence of diabetes was the same as with that seen in a matched, observation group (subjects followed prospectively as part of the University of Florida natural history studies) (age, sex, ICA, insulin autoantibodies, duration of ICA prior to enrollment, FPIR, and glucose intolerance; p = 0.39), as was the rate of progression (p = 0.79). There was a higher rate of progression to diabetes in the group with abnormal glucose tolerance at baseline than in those with normal baseline glucose tolerance (p = 0.003). Interestingly, in non-progressors, as opposed to progressors, there was no fall in C-peptide (peak and area under the curve) production regardless of the type of tolerance testing (mixed meal, oral or intravenous) over time (p < 0.001). In this study, in the dose and regimen of NPH insulin used, insulin did not delay or prevent the development of type 1 diabetes. However, preservation of C-peptide production in the prediabetic period appears to indicate non-progression to clinical disease and may serve as a new surrogate for determining response to preventative efforts. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin, Isophane; Male; Middle Aged; Pilot Projects; Prediabetic State; Risk | 2004 |
Temporary preservation of beta-cell function by diazoxide treatment in childhood type 1 diabetes.
We examined the effect of diazoxide, an ATP-sensitive K(+) channel opener and inhibitor of insulin secretion, on beta-cell function and remission in children at clinical onset of type 1 diabetes.. A total of 56 subjects (21 girls and 35 boys, age 7-17 years) were randomized to 3 months of active treatment (diazoxide 5-7.5 mg/kg in divided doses) or placebo in addition to multiple daily insulin injections and were followed for 2 years.. Diazoxide decreased circulating C-peptide concentrations by approximately 50%. After cessation of the treatment, basal and meal-stimulated C-peptide concentrations increased to a maximum at 6 months, followed by a decline. Meal-stimulated C-peptide concentration was significantly higher at 12 months (0.43 +/- 0.22 vs. 0.31 +/- 0.26 nmol/l, P = 0.018) and tended to fall less from clinical onset to 24 months in the diazoxide- vs. placebo-treated patients (-0.05 +/- 0.24 vs. -0.18 +/- 0.26 nmol/l, P = 0.064). At 24 months, the meal-stimulated C-peptide concentrations were 0.24 +/- 0.20 and 0.20 +/- 0.17 nmol/l, respectively. Side effects of diazoxide were prevalent.. This study demonstrates that partial inhibition of insulin secretion for 3 months at onset of childhood type 1 diabetes suspends the period of remission and temporarily preserves residual insulin production. Further evaluation of the full potential of beta-cell rest will require compounds with less side effects as well as protocols optimized for sustained secretory arrest. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Diazoxide; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Islets of Langerhans; Male; Vasodilator Agents | 2004 |
Oral insulin therapy to prevent progression of immune-mediated (type 1) diabetes.
Repeated ingestion of insulin has been suggested as an immune tolerization therapy to prevent immune-mediated (type 1) diabetes. We performed a placebo-controlled, two-dose, oral insulin tolerance trial in newly diagnosed (< 2 years) diabetic patients who had required insulin replacement for less than 4 weeks and were found to have cytoplasmic islet cell autoantibodies (ICAs). No oral hypoglycemic agents were permitted during the trial. Endogenous insulin reserves were estimated at six-month intervals by plasma C-peptide responses to a mixed meal. Positive ICAs were found in 262 (31%) of the 846 patients screened. Of the 197 who agreed to participate, 187 could be followed for 6 to 36 months. Endogenous insulin retention was dependent upon initial stimulated C-peptide response, age at diabetes onset, and numbers of specific islet cell autoantibodies found. Oral insulin improved plasma C-peptide responses in patients diagnosed at ages greater than 20 years, best seen at the low (1 mg/day) over the high (10 mg/day) insulin dose (P = .003 and P = .01, respectively). In patients diagnosed before age 20 years, the 1 mg dose was ineffective, whereas the 10 mg dose actually accelerated C-peptide loss (P = .003). There were no adverse effects. If confirmed, these findings suggest that diabetic patients over age 20 years with ICA evidence of late-onset immune-mediated diabetes should be considered for oral insulin at 1 mg/day to better retain endogenous insulin secretion. Topics: Administration, Oral; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Drug Tolerance; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Placebos; Time Factors | 2004 |
Glutamic acid decarboxylase and ICA512/IA-2 autoantibodies as disease markers and relationship to residual beta-cell function and glycemic control in young type 1 diabetic patients.
Circulating autoantibodies (Ab) to islet autoantigens, glutamic acid decarboxylase (GAD(65)), and tyrosine phosphatase ICA512/IA-2 have been proposed as predictive markers of type 1 diabetes mellitus. To ascertain residual beta-cell function and the clinical relevance for monitoring autoimmunity after clinical manifestation of disease, we studied 63 children at diagnosis of type 1 diabetes (mean SD age 7.5 +/- 4 years) and 91 adolescent patients with type 1 diabetes (age 14.7 +/- 1.6 years) with a mean duration of disease of 7 +/- 3.5) years. Forty-two normal adolescent subjects (age 14.6 +/- 1.8 years) without a family history of diabetes were the control group. Anti-GAD(65) and ICA512/IA-2 Ab were assessed by a quantitative radioimmunoprecipitation assay. The relationship between humoral autoimmunity and clinical parameters was explored. GAD(65) and ICA512/IA-2 Ab were detected in 56% and 63% of newly diagnosed children and the prevalence was not different in relationship to clinical characteristics. Levels of GAD(65) Ab positively correlated with diagnosis age (P <.05). Both Ab were associated with islet cell antibodies (ICA) (P <.05), but one fifth of patients had at least 1 of the 2 Ab and absent ICA. At onset, only age showed a significant relationship to residual C-peptide secretion. Among the cohort of patients with diabetes of short-mid duration, GAD(65) and ICA512/IA-2 Ab were present in 44% and 45% of cases (P >.05 and P <.05 v newly diagnosed children, respectively) and more patients were identified by these Ab (68%) than by ICA alone (34%) (P <.05). In this cohort, levels of ICA512/IA-2 Ab negatively correlated with levels of glycosylated hemoglobin (HbA(1c)) (P <.005) and with daily insulin requirement (P <.05). Moreover, the presence of some residual C-peptide secretion was significantly associated with the presence of ICA512/IA-2 Ab (P <.05). Our findings confirm that positivity for either GAD(65) or ICA512/IA-2 Ab is a highly sensitive marker of type 1 diabetes in the pediatric age group, identifying a group of patients with absent ICA immunofluorescence. The persistence of Ab to islet tyrosine phosphatase possibly represents a marker of better glycemic control and less insulin requirement, indicating residual beta-cell function, thus conferring clinical and prognostic relevance to these Ab, as well as potential usefulness in intervention strategies. Topics: Adolescent; Autoantibodies; Autoantigens; Biomarkers; Blood Glucose; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Islets of Langerhans; Isoenzymes; Male; Membrane Proteins; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Radioimmunoassay; Receptor-Like Protein Tyrosine Phosphatases, Class 8 | 2003 |
Amelioration of sensory nerve dysfunction by C-Peptide in patients with type 1 diabetes.
Studies have demonstrated that proinsulin C-peptide stimulates the activities of Na(+),K(+)-ATPase and endothelial nitric oxide synthase, both of which are enzyme systems of importance for nerve function and known to be deficient in type 1 diabetes. The aim of this randomized double-blind placebo-controlled study was to investigate whether C-peptide replacement improves nerve function in patients with type 1 diabetes. Forty-nine patients without symptoms of peripheral neuropathy were randomized to either 3 months of treatment with C-peptide (600 nmol/24 h, four doses s.c.) or placebo. Forty-six patients (15 women and 31 men, aged 29 years, diabetes duration 10 years, and HbA(1c) 7.0%) completed the study. Neurological and neurophysiological measurements were performed before and after 6 and 12 weeks of treatment. At baseline the patients showed reduced nerve conduction velocities in the sural nerve (sensory nerve conduction velocity [SCV]: 50.9 +/- 0.70 vs. 54.2 +/- 1.2 m/s, P < 0.05) and peroneal nerve (motor nerve conduction velocity: 45.7 +/- 0.55 vs. 53.5 +/- 1.1 m/s, P < 0.001) compared with age-, height-, and sex-matched control subjects. In the C-peptide treated group there was a significant improvement in SCV amounting to 2.7 +/- 0.85 m/s (P < 0.05 compared with placebo) after 3 months of treatment, representing 80% correction of the initial reduction in SCV. The change in SCV was accompanied by an improvement in vibration perception in the patients receiving C-peptide (P < 0.05 compared with placebo), whereas no significant change was detectable in cold or heat perception. In conclusion, C-peptide administered for 3 months as replacement therapy to patients with early signs of diabetic neuropathy ameliorates nerve dysfunction. Topics: Adult; Age of Onset; Blood Pressure; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Insulin; Male; Neural Conduction; Neurologic Examination; Patient Selection; Peripheral Nervous System Diseases; Placebos; Time Factors | 2003 |
Effect of glucagon-like peptide 1 (7-36 amide) on insulin-mediated glucose uptake in patients with type 1 diabetes.
To examine the insulinomimetic insulin-independent effects of glucagon-like peptide (GLP)-1 on glucose uptake in type 1 diabetic patients.. We used the hyperinsulinemic-euglycemic clamp (480 pmol. m(-2) x min(-1)) in paired randomized studies of six women and five men with type 1 diabetes. In the course of one of the paired studies, the subjects also received GLP-1 at a dose of 1.5 pmol. kg(-1) x min(-1). The patients were 41 +/- 3 years old with a BMI of 25 +/- 1 kg/m(2). The mean duration of diabetes was 23 +/- 3 years.. Plasma glucose was allowed to fall from a fasting level of approximately 11 mmol/l to 5.3 mmol/l in each study and thereafter was held stable at that level. Plasma insulin levels during both studies were approximately 900 pmol/l. Plasma C-peptide levels did not change during the studies. In the GLP-1 study, plasma total GLP-1 levels were elevated from the fasting level of 31 +/- 3 to 150 +/- 17 pmol/l. Plasma glucagon levels fell from the fasting levels of approximately 14 pmol/l to 9 pmol/l during both paired studies. Hepatic glucose production was suppressed during the glucose clamps in all studies. Glucose uptake was not different between the two studies ( approximately 40 micromol. kg(-1) x min(-1)).. GLP-1 does not augment insulin-mediated glucose uptake in lean type 1 diabetic patients. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Glucose Clamp Technique; Humans; Hyperinsulinism; Insulin; Liver; Male; Neurotransmitter Agents; Peptide Fragments; Peptides | 2003 |
C-peptide increases forearm blood flow in patients with type 1 diabetes via a nitric oxide-dependent mechanism.
Proinsulin C-peptide has been shown to increase muscle blood flow in type 1 diabetic patients. The underlying mechanism is not fully understood. The aim of this study was to evaluate if the vasodilator effect of C-peptide is mediated by nitric oxide (NO). Eleven type 1 diabetic patients were studied two times and randomized to administration of intravenous and intra-arterial infusion of C-peptide or saline. Forearm blood flow (FBF) was measured by venous occlusion plethysmography during infusion of C-peptide or saline before, during, and after NO synthase (NOS) blockade. Endothelium-dependent and -independent vasodilatation was evaluated by administration of acetylcholine and sodium nitroprusside, respectively. FBF increased by 35% during intravenous C-peptide (P < 0.01) but not during saline infusion (-2%, not significant). NOS blockade resulted in a more pronounced reduction in FBF during intravenous C-peptide than during saline infusion (-41 vs. -26%, P < 0.05). Intra-arterial C-peptide failed to increase FBF during NOS blockade. However, when C-peptide was given after the recovery from NOS blockade, FBF rose by 30% (P < 0.001). The vasodilator effects of acetylcholine and nitroprusside were not influenced by C-peptide. It is concluded that the stimulatory effect of C-peptide on FBF in type 1 diabetic patients is mediated via the NO system and that C-peptide increases basal endothelial NO levels. Topics: Acetylcholine; Adult; Blood Flow Velocity; C-Peptide; Diabetes Mellitus, Type 1; Forearm; Humans; Infusions, Intravenous; Insulin; Male; Nitric Oxide; Nitric Oxide Synthase; Nitroprusside; omega-N-Methylarginine; Regional Blood Flow; Vasodilator Agents | 2003 |
[Prognostic value of humoral and metabolic markers as an evaluation of risk for developing type 1 diabetes].
Clinical symptoms of type 1 diabetes are preceded by a long period of prediabetes stage characterised by anti-islet antibodies occurrence as well as insulin and C-peptide secretion disturbances. The aim of this study was to define the prognostic value of type 1 diabetes antiislet humoral markers (ICA, anti-GAD, anti-IA2 and IAA) and to find out thresholds for insulin and C-peptide levels at which clinically overt type 1 diabetes develops. Antiislet antibodies, serum C-peptide and insulin were determined in 86 children who, considering their antiislet autoantibodies levels, were classified as prediabetics (mean value of the observation period: 50 months). 8 (9.3%) children, who after a mean time of 35 months of prediabetes stage developed clinically overt type 1 diabetes, were selected from this group. ICA were determined by indirect immunofluorescence; anti-GAD and IAA by radioimmunoprecipitation. C-peptide and insulin levels were evaluated by radioimmunologic assays (CIS Bio International, France). Kaplan-Meier life table analysis revealed pEFS=0.89 after 92 months' observation. The risk of developing diabetes within 80 months was established. For children with positive ICA the risk rate was 0.21, for ICA and anti-GAD positive individuals - 0.39, and for ICA and IA2 positive - 0.74. A significant difference in insulin and C-peptide levels was found between children who developed clinically overt type 1 diabetes and those in prediabetes stage (9.90 vs. 21.45 micro U/ml, p<0.008; 0.34 vs. 0.67 pM/ml, p<0.001 respectively). For both hormones thresholds for high risk of developing clinically overt diabetes were pointed out. Using ROC method the threshold for insulin was determined at 12.9 micro U/ml, for C-peptide at 0.45 pM/ml. Not only the presence and levels of autoantibodies but also the plasma concentrations of C-peptide and insulin are important prognostics of clinical onset of type 1 diabetes mellitus. Topics: Adolescent; Antibody Formation; Autoantibodies; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Insulin Antibodies; Male; Prediabetic State; Prognosis; Risk Assessment; ROC Curve | 2003 |
The pathophysiology of diabetes involves a defective amplification of the late-phase insulin response to glucose by glucose-dependent insulinotropic polypeptide-regardless of etiology and phenotype.
The effect of the insulinotropic incretin hormone, glucagon-like peptide-1 (GLP-1), is preserved in typical middle-aged, obese, insulin-resistant type 2 diabetic patients, whereas a defective amplification of the so-called late-phase plasma insulin response (20-120 min) to glucose by the other incretin hormone, glucose-dependent insulinotropic polypeptide (GIP), is seen in these patients. The aim of the present investigation was to evaluate plasma insulin and C-peptide responses to GLP-1 and GIP in five groups of diabetic patients with etiology and phenotype distinct from the obese type 2 diabetic patients. We studied (six in each group): 1) patients with diabetes mellitus secondary to chronic pancreatitis; 2) lean type 2 diabetic patients (body mass index < 25 kg/m(2)); 3) patients with latent autoimmune diabetes in adults; 4) diabetic patients with mutations in the HNF-1alpha gene [maturity-onset diabetes of the young (MODY)3]; and 5) newly diagnosed type 1 diabetic patients. All participants underwent three hyperglycemic clamps (2 h, 15 mM) with continuous infusion of saline, 1 pmol GLP-1 (7-36)amide/kg body weight.min or 4 pmol GIP pmol/kg body weight.min. The early-phase (0-20 min) plasma insulin response tended to be enhanced by both GIP and GLP-1, compared with glucose alone, in all five groups. In contrast, the late-phase (20-120 min) plasma insulin response to GIP was attenuated, compared with the plasma insulin response to GLP-1, in all five groups. Significantly higher glucose infusion rates were required during the late phase of the GLP-1 stimulation, compared with the GIP stimulation. In conclusion, lack of GIP amplification of the late-phase plasma insulin response to glucose seems to be a consequence of diabetes mellitus, characterizing most, if not all, forms of diabetes. Topics: Adult; Aged; Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; DNA-Binding Proteins; Female; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Glucose; Hepatocyte Nuclear Factor 1; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 1-beta; Humans; Hyperglycemia; Insulin; Islets of Langerhans; Male; Middle Aged; Neurotransmitter Agents; Nuclear Proteins; Pancreatitis; Peptide Fragments; Phenotype; Protein Precursors; Transcription Factors | 2003 |
Multicenter prevention trial of slowly progressive type 1 diabetes with small dose of insulin (the Tokyo study): preliminary report.
In 1996, we designed a randomized multicenter study to assess the effects of small doses of insulin on beta cell failure in slowly progressive type 1 diabetes (the Tokyo Study). We report here the preliminary results of this study. Glutamic acid decarboxylase 65 antibody (GADA)-positive patients were randomly divided into 2 groups: one group received insulin (Ins group), the other a sulfonylurea (SU group). Fifty-four patients (24 Ins group, 30 SU group) were analyzed at the end of a 4-year period. All patients underwent a 75 g oral-glucose test (O-GTT) every 6-12 months. The insulin-dependent stage was defined based on an integrated value of serum C-peptide levels on O-GTT ( summation operator CPR; sum of CPR at 0, 30, 60, 90, and 120 min) below 4.0 ng/mL. The summation operator CPR in the SU group decreased progressively from 22.0 +/- 10.6 to 11.3 +/- 7.5 ng/mL over the 48-month period (p < 0.001 vs. baseline). The summation operator CPR in the Ins group was unchanged. Among the SU group, 30% of subjects (9/30) progressed to IDDM, while 8.3% of Ins group subjects (2/24) progressed to IDDM (p = 0.087). With regard to the subjects who had a preserved C-peptide response ( summation operator CPR >/= 10 ng/mL), the proportion of SU group subjects who progressed to IDDM was significantly higher than that of the Ins group (7/28, 25% vs. 0/21, 0%, p = 0.015). Among subjects with a high GADA titer (>/=0 U/mL), 9/14 (64.3%) of the SU group, but only 2/16 (12.5%) of the Ins group, developed IDDM (p = 0.0068). As to those with a high GADA titer and a preserved C-peptide response, SU group subjects progressed to IDDM (7/12, 58.3%) more frequently than Ins group subjects (0/14, 0%) (p = 0.0012). In summary, our results suggest that small doses of insulin effectively prevent beta cell failure in slowly progressive type 1 diabetes. We recommend avoiding SU treatment and instead administering insulin to NIDDM patients with high GADA titer. Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Dose-Response Relationship, Drug; Glucose Tolerance Test; Glutamate Decarboxylase; Humans; Insulin; Isoenzymes; Prospective Studies | 2003 |
A 2-year pilot trial of continuous subcutaneous insulin infusion versus intensive insulin therapy in patients with newly diagnosed type 1 diabetes (IMDIAB 8).
In a pilot study, the metabolic effects of continuous subcutaneous insulin infusion (CSII) versus intensive subcutaneous insulin therapy (ISIT) started at diagnosis in patients with Type 1 diabetes and continued for a 2-year period were evaluated and compared. Twenty-three patients (between 12 and 35 years old, mean +/- SD 18.4 +/- 9 years) were randomized into two treatment groups (CSII vs. ISIT), and both received supplemental nicotinamide (NA), 25 mg/kg of body weight. CSII was started immediately after admission to the hospital. Parameters of metabolic control [insulin dose, hemoglobin A1c (HbA1c), and C-peptide] were evaluated for a 2-year follow-up period. Data are presented for a total of 19 patients who remained in the study for its duration. Two years after diagnosis, mean +/- SD HbA1c was 6.3 +/- 0.5% and 6.2 +/- 0.3% for the CSII and ISIT groups, respectively (p=not significant). Compared with baseline values, an increase of baseline C-peptide of 38% for the CSII group and 27% for the ISIT group was observed; however, the difference between the groups was not significant. The insulin requirement for the entire duration of the study, but not at entry and 3 months, was significantly higher in CSII compared with ISIT patients (0.62 +/- 0.4 IU/kg/day vs. 0.3 +/- 0.4 IU/kg/day, respectively; p<0.01). After trial completion patients on CSII continued with this mode of therapy. Implementation of CSII as well as ISIT at diagnosis of Type 1 diabetes and continuation for 2 years thereafter achieved similar and optimal metabolic control, but more insulin was required with the CSII group. Both types of intensive insulin therapy combined with NA are able to preserve C-peptide secretion or even increase baseline levels for up to 2 years after diagnosis. Topics: Analysis of Variance; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Insulin Infusion Systems; Pilot Projects; Reproducibility of Results; Treatment Outcome | 2003 |
C-peptide exerts beneficial effects on myocardial blood flow and function in patients with type 1 diabetes.
Myocardial dysfunction, perfusion abnormalities, and the extent to which these abnormalities may be reversed by C-peptide administration was assessed in type 1 diabetic patients. Eight patients were studied before and during a 0.84-mg/kg dipyridamole administration using a randomized double-blind crossover protocol with infusion of C-peptide (6 pmol x kg(-1) x min(-1)) or saline during 60 min on two different days. Myocardial function was measured as peak myocardial velocity during systole (Vs) and early diastole (Vd) by pulsed tissue Doppler imaging. Myocardial contrast echocardiography was used for assessment of myocardial blood volume (SI(max)) and myocardial blood flow index (MBFI) calculated from the relation between trigger interval and signal intensity. Eight age-matched healthy volunteers served as control subjects. In the basal state, Vd (13.8 +/- 0.6 vs. 15.6 +/- 0.5 cm/s, P < 0.04) and SI(max) (6.6 +/- 0.6 vs. 8.2 +/- 0.6 a.u. P < 0.04) were reduced in patients compared with control subjects. Dipyridamole administration significantly increased indexes of myocardial function and blood flow to a similar extent in patients and control subjects. During C-peptide administration, Vs and Vd increased by 12% (P = 0.03), SI(max) increased from 6.6 +/- 0.6 to 8.1 +/- 0.7 a.u. (P < 0.02), and MBFI increased from 3.3 +/- 0.4 to 5.3 +/- 0.9 (P < 0.05). The results demonstrate that type 1 diabetic patients have impaired myocardial function and perfusion in the basal state that can be improved by short-term replacement of C-peptide. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Coronary Circulation; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Echocardiography; Heart Rate; Humans; Insulin; Male | 2002 |
When should determination of ketonemia be recommended?
Diabetic ketoacidosis is a serious complication of type diabetes. beta-Hydroxybutyrate (beta-OHB) accounts for about 75% of ketones, and blood concentration can be determined with a sensor. The aim of this study was to investigate the frequency and degree of ketonemia in daily life of children with diabetes and to make a base for recommendations for determination of ketonemia in clinical practice. During 3 months 45 patients with type 1 diabetes since 1-10 years old (mean 4.4 +/- 3.3 years old) at the pediatric clinic in Linköping, Sweden, performed 24-h profiles (eight determinations) in 2 weeks with blood glucose and beta-OHB. The children performed 11,189 blood glucose and 7,057 beta-OHB measurements. Only 0.3% (n = 21) of beta-OHB measurements were > or = 1.0 mmol/L. An beta-OHB concentration > 0.2 mmol/L was more common in the morning than during the rest of the day (p < 0.001). Young children (4-7 years old) had values > or = 0.2 mmol/L more often than adolescents (p < 0.001). Blood glucose values > 15 mmol/L were more often accompanied by beta-OHB > 0.2 mmol/L (p < 0.001). High beta-OHB concentrations are rare in diabetic children with reasonably good metabolic control. Already a value > 0.4 mmol/L seems abnormal, and we recommend that patients retest glucose and ketones with beta-OHB > 0.4 mmol/L. Furthermore, we recommend that diabetic children and adolescents measure beta-OHB when symptoms like nausea or vomiting occur to differentiate ketoacidosis from gastroenteritis, and during infections, during periods with high blood glucose (> 15 mmol/L), and if they notice ketonuria. Monitoring beta-OHB should be routine for patients on pump therapy. Topics: 3-Hydroxybutyric Acid; Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Infant; Insulin; Ketones; Male | 2002 |
The benefits of metformin therapy during continuous subcutaneous insulin infusion treatment of type 1 diabetic patients.
This study was designed to assess the insulin-sparing effect of oral administration of metformin along with a continuous subcutaneous insulin infusion (CSII) for the treatment of type 1 diabetic patients.. A total of 62 patients (25 women and 37 men) were studied in a monocenter, randomized, double-blind placebo-controlled study, comparing metformin (850 mg b.i.d.) with placebo in association with CSII during a 6-month period.. Treatment with metformin was associated with a reduction in daily insulin requirements between V0 and V6 of -4.3 +/- 9.9 units (-7.8 +/- 18%) compared with an increase with placebo treatment of 1.7 +/- 8.3 units (2.8 +/- 12.7%) (P = 0.0043). A decrease in basal requirement of insulin was also observed in patients treated with metformin of -2.6 +/- 3.2 units (-7.9 +/- 23.8%) compared with an increase with placebo treatment of 1.9 +/- 5.7 units (8.8 +/- 27.1%) (P = 0.023). HbA(1c) remained unchanged in treatment with metformin and placebo between V0 and V6. The number of hypoglycemic events (<60 mg/dl) was similar in both groups. Significant reductions of total cholesterol (P = 0.04) and LDL cholesterol (P = 0.05) were observed in patients treated with metformin. Gastrointestinal events, including diarrhea and abdominal pain, were reported in three patients in the metformin group who discontinued the trial. Mild or moderate gastrointestinal side effects were also reported in eight patients treated with metformin and two patients treated with placebo (P = 0.069).. Metformin was found to be a safe insulin-sparing agent, when used in combination with CSII for the treatment of type 1 diabetes. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin Infusion Systems; Male; Metformin; Placebos; Time Factors | 2002 |
Slowly progressing type 1 diabetes: persistence of islet cell autoantibodies is related to glibenclamide treatment.
Several experimental studies in rats have demonstrated that sulfonylurea treatment increases autoantigen expression in B-cells. This phenomenon may be deleterious for the preservation of residual beta cell function in patients with slowly progressing type 1 diabetes or latent autoimmune diabetes of adult (LADA).. The aim of the present study was to evaluate whether the exclusion of glibenclamide in the treatment of ICA positive type 2 diabetic patients may diminish or halt the humoral autoimmune response against B-cells as well as improve metabolic control and insulin secretion.. Fourteen type 2 diabetic patients with pancreatic autoimmunity (ICA+ and GABA+) and treated with insulin and glibenclamide (duration of disease 2.0 +/- 2.2, range 0.1-7 years and age 53 +/- 12.5, range 36-75 years) were studied. Patients were randomly assigned to two treatment groups, Group 1: insulin monotherapy (n = 8, age 53 +/- 6.4 years) (Exclusion of glibenclamide) and, Group 2: insulin plus glibenclamide (n = 6, age 53.5 +/- 16.9) (Unmodified treatment). Both groups were investigated at the beginning of the study and after one year for the following parameters: ICA and anti-GAD65 antibodies, fasting glucose and fasting C-peptide.. In group 1, six out of eight patients became ICA negative while all patients in group 2 remained ICA positive (p = 0.0097). Fasting glucose concentrations improved in group 1 (4.6 +/- 2.8) in relation to group 2 (11.5 +/- 5.5, p = 0.0023) after one year of treatment. No differences were found for anti-GAD antibodies and fasting C-Peptide between the groups.. These data show that exclusion of glibenclamide in the treatment of ICA+ type 2 diabetic patients partially decreases specific autoimmunity against endocrine pancreatic cells and improves metabolic control. This may reflect decreased expression of B-cell autoantigens suggesting that insulin monotherapy is a better choice for the treatment of LADA. Topics: Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Glyburide; Humans; Hypoglycemic Agents; Islets of Langerhans; Isoenzymes | 2002 |
Effect of C-peptide on glucose metabolism in patients with type 1 diabetes.
Topics: Adult; Age of Onset; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glucose Clamp Technique; Humans; Infusions, Intravenous; Insulin; Male; Middle Aged; Placebos | 2002 |
Anti-CD3 monoclonal antibody in new-onset type 1 diabetes mellitus.
Type 1 diabetes mellitus is a chronic autoimmune disease caused by the pathogenic action of T lymphocytes on insulin-producing beta cells. Previous clinical studies have shown that continuous immune suppression temporarily slows the loss of insulin production. Preclinical studies suggested that a monoclonal antibody against CD3 could reverse hyperglycemia at presentation and induce tolerance to recurrent disease.. We studied the effects of a nonactivating humanized monoclonal antibody against CD3--hOKT3gamma1(Ala-Ala)--on the loss of insulin production in patients with type 1 diabetes mellitus. Within 6 weeks after diagnosis, 24 patients were randomly assigned to receive either a single 14-day course of treatment with the monoclonal antibody or no antibody and were studied during the first year of disease.. Treatment with the monoclonal antibody maintained or improved insulin production after one year in 9 of the 12 patients in the treatment group, whereas only 2 of the 12 controls had a sustained response (P=0.01). The treatment effect on insulin responses lasted for at least 12 months after diagnosis. Glycosylated hemoglobin levels and insulin doses were also reduced in the monoclonal-antibody group. No severe side effects occurred, and the most common side effects were fever, rash, and anemia. Clinical responses were associated with a change in the ratio of CD4+ T cells to CD8+ T cells 30 and 90 days after treatment.. Treatment with hOKT3gamma1(Ala-Ala) mitigates the deterioration in insulin production and improves metabolic control during the first year of type 1 diabetes mellitus in the majority of patients. The mechanism of action of the anti-CD3 monoclonal antibody may involve direct effects on pathogenic T cells, the induction of populations of regulatory cells, or both. Topics: Adolescent; Adult; Antibodies, Monoclonal; C-Peptide; CD3 Complex; CD4-CD8 Ratio; Child; Cytokines; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Lymphocyte Count; Male | 2002 |
No evidence for accumulation of insulin glargine (LANTUS): a multiple injection study in patients with Type 1 diabetes.
Insulin glargine is a long-acting insulin analogue that is metabolically active for at least 24 h. We investigated the multiple-dose pharmacokinetic properties of insulin glargine to determine whether daily injections lead to the accumulation of circulating insulin levels and a corresponding decrease in blood glucose levels in patients with Type 1 diabetes.. Fifteen patients using preprandial insulin lispro (mean age 36 +/- 9 years, body mass index 24.6 +/- 2.2 kg/m(2)) completed the study. Each patient's optimal insulin glargine dose was determined during a dose-finding phase. After a washout period, patients were treated over 12 days with a constant daily dose of insulin glargine injected in the abdominal subcutaneous adipose tissue at 22:00 h, and with preprandial insulin lispro. Free serum insulin (FSI) and blood glucose concentrations were assessed hourly after the first, fourth, and eleventh injection, after which patients fasted for 24 h and did not use any other insulin preparation.. There were no changes in daily insulin doses during the dose-finding phase (insulin glargine: initial dose 24 +/- 6 IU, mean change 0 +/- 3 IU; insulin lispro: 18 +/- 9 IU, 0 +/- 7 IU). The time course of FSI was comparable on the three pharmacokinetic study days. Notably, the trough FSI at the end of the sampling periods was almost identical (day 1, 79 +/- 56 pmol/l, day 4, 77 +/- 56 pmol/l, day 11, 86 +/- 60 pmol/l). No changes occurred in any of the pharmacokinetic parameters studied.. There is no evidence that insulin glargine accumulates after multiple injections over 12 days. These results indicate that the predetermined dose of insulin glargine will not need to be reduced after commencing treatment because of a risk of accumulation. Topics: C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Insulin Glargine; Insulin Lispro; Insulin, Long-Acting; Metabolic Clearance Rate; Time Factors | 2002 |
IA-2 antibody-negative status predicts remission and recovery of C-peptide levels in type 1 diabetic patients treated with cyclosporin.
The use of cyclosporin in recent-onset type 1 diabetes has demonstrated the potential for immune intervention in the treatment and prevention of the disease. However, a proportion of patients failed to respond to cyclosporin treatment. Indicators of resistance to immune intervention would be valuable for the most effective use of such therapies in disease prevention. The aim of this study was to determine whether presence of IA-2 antibodies is such a marker.. IA-2 antibodies were determined by radioligand binding assay in sera from patients recruited into the Canadian-European cyclosporin trial. Insulin dose requirements and glucagon-stimulated C-peptide secretion were analyzed in patients grouped according to IA-2 antibody status at entry.. Cyclosporin treatment had no significant effect on frequency of IA-2 antibodies during the 1 year of treatment. Cyclosporin caused significant reduction in insulin requirements and significant increases in C-peptide secretion mainly in patients negative for IA-2 antibodies. Analysis of GAD antibodies in combination with antibodies to IA-2 indicated that the group most resistant to cyclosporin were IA-2 antibody positive, GAD antibody negative.. The results demonstrate that IA-2 antibody analysis is valuable in identifying individuals for whom immunosuppressive treatment would be most effective. Topics: Adult; Autoantibodies; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Male; Placebos; Predictive Value of Tests; Time Factors | 2002 |
Pancreas resection and islet autotransplantation for end-stage chronic pancreatitis.
To assess the safety and efficacy of islet autotransplantation (IAT) combined with total pancreatectomy (TP) to prevent diabetes.. There have been recent concerns regarding the safety of TP and IAT. This is thought to be related to the infusion of large volumes of unpurified pancreatic digest into the portal vein. Minimizing the volume of islet tissue by purifying the pancreatic digest has not been previously evaluated in terms of the postoperative rate of death and complications, pain relief, and insulin independence.. During a 54-month period, 24 patients underwent pancreas resection with IAT. Islets were isolated using collagenase and a semiautomated method of pancreas digestion. Where possible, islets were purified on a density gradient and COBE processor. Islets were embolized into the portal vein, within the spleen and portal vein, or within the spleen alone. The total median volume of digest was 9.9 mL.. The median number of islets transplanted was 140,419 international islet equivalents per kilogram. The median increase in portal pressure was 8 mmHg. Early complications included duodenal ischemia, a wedge splenic infarct, partial portal vein thrombosis, and splenic vein thrombosis. Intraabdominal adhesions were the main source of long-term problems. Eight patients developed transient insulin independence. Three patients were insulin-independent as of this writing. Patients had significantly decreased insulin requirements and glycosylated hemoglobin levels compared with patients undergoing TP alone. Of the patients alive and well as of this writing, four had failed to gain relief of their abdominal pain and were still opiate-dependent.. Combined TP and IAT can be a safe surgical procedure. Unfortunately, almost all patients were still insulin-dependent, but they had decreased daily insulin requirements and glycosylated hemoglobin levels compared with patients undergoing TP alone. A prospective randomized study is therefore needed to assess the long-term benefit of TP and IAT on diabetic complications. Topics: Adult; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; England; Female; Humans; Islets of Langerhans Transplantation; Male; Middle Aged; Pancreatectomy; Pancreatitis; Postoperative Complications; Prospective Studies; Statistics, Nonparametric | 2001 |
Dose-response relation of liquid aerosol inhaled insulin in type I diabetic patients.
The AERx insulin Diabetes Management system (AERx iDMS) is a liquid aerosol device that enables insulin to be administered to the peripheral parts of the lung. This study aimed to compare the pharmacokinetic and pharmacodynamic properties of insulin which is inhaled using AERx iDMS with insulin which is subcutaneously administered.. In total, 18 C-peptide negative patients with Type I (insulin-dependent) diabetes mellitus participated in this randomised, open-label, 5-period crossover trial. Human regular insulin was administered subcutaneously (0.12 U/kg body weight) or inhaled by means of the AERx iDMS (dosages 0.3, 0.6, 1.2, and 1.8 U/kg body weight). Thereafter plasma glucose was kept constant at 7.2 mmol/l for a 10-h period (glucose clamp technique).. Inhaled insulin provided a dose-response relation that was close to linear for both pharmacokinetic (AUC-Ins(0-10 h); Cmax-Ins) and pharmacodynamic (AUC-GIR(0-10 h); GIRmax) parameters. Time to maximum insulin concentration (Tmax-Ins) and time to maximum glucose infusion rate (TGIRmax) were shorter with inhaled insulin than with subcutaneous administration. The pharmacodynamic system efficiency of inhaled insulin (AUC-GIR(0-6 h) was 12.7% (95% C.I.: 10.2-15.6).. The inhalation of soluble human insulin using the AERx iDMS is feasible and provides a clear dose response. Further long-term studies are required to investigate safety aspects, HbA1c values, incidence of hypoglycaemic events and the quality of life. Topics: Administration, Inhalation; Adult; Aerosols; Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Time Factors | 2001 |
Photopheresis at onset of type 1 diabetes: a randomised, double blind, placebo controlled trial.
In recent years photopheresis, an extracorporeal form of photochemotherapy using psoralen and ultraviolet A irradiation of leucocytes, has been claimed to be an effective form of immunomodulation.. To evaluate its effect in type 1 diabetes we performed a double blind, controlled study using placebo tablets and sham pheresis in the control group.. A total of 49 children, aged 10-18 years of age at diagnosis of type 1 diabetes were included; 40 fulfilled the study and were followed for three years (19 received active treatment with photopheresis and 21 placebo treatment).. The actively treated children secreted significantly more C peptide in urine during follow up than control children. C peptide values in serum showed corresponding differences between the two groups. The insulin dose/kg body weight needed to achieve satisfactory HbA1c values was always lower in the photopheresis group; there was no difference between the groups regarding HbA1c values during follow up. The treatment was well accepted except for nausea (n = 3) and urticaria (n = 1) in the actively treated group. There were no differences regarding weight or height, or episodes of infection between the two groups during follow up.. Photopheresis does have an effect in addition to its possible placebo effect, shown as a weak but significant effect on the disease process at the onset of type 1 diabetes, an effect still noted after three years of follow up. Topics: Adolescent; Area Under Curve; C-Peptide; Child; Combined Modality Therapy; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Male; Photopheresis; Statistics, Nonparametric | 2001 |
Effects of C-peptide on forearm blood flow and brachial artery dilatation in patients with type 1 diabetes mellitus.
Recent studies suggest that C-peptide increases blood flow in both exercising and resting forearm in patients with type 1 diabetes. Now we have studied the effect of C-peptide administration on endothelial-mediated and non-endothelial-mediated arterial responses as well as central haemodynamics in 10 patients with type 1 diabetes in a placebo-controlled double-blind study. Euglycaemia was maintained with an i.v. insulin infusion before and during the study. A high-resolution ultrasound technique and Doppler echocardiography were used to assess haemodynamic functions. Brachial artery blood flow and brachial artery diameter were measured in the basal state, 1 and 10 min after reactive hyperaemia and 4 min after sublingual glyceryl trinitrate administration (GTN; endothelial-independent vasodilatation), both before and after the end of 60-min C-peptide (6 pmol kg-1 min-1) or saline infusion periods. Echocardiographic measurements were also performed before and at the end of the infusion periods. Seven healthy age-matched males served as controls for vascular studies. The patients showed a blunted brachial dilatation after reactive hyperaemia in comparison with the healthy controls (2.1 +/- 0.5% vs. 9.3 +/- 0.3%, P < 0.001), indicating a disturbed endothelial function. C-peptide infusion compared with saline resulted in increased basal blood flow (33 +/- 6%, P < 0.001) and brachial arterial dilatation (4 +/- 1%, P < 0.05). Left ventricular ejection fraction seemed to be improved (5 +/- 2%, P < 0.05) at the end of C-peptide infusion compared with placebo. The vascular response to reactive hyperaemia and GTN was not affected by C-peptide infusion. Our results demonstrate that physiological concentrations of C-peptide increase resting forearm blood flow, brachial artery diameter and left ventricular systolic function in patients with type 1 diabetes. Topics: Adult; Blood Glucose; Blood Pressure; Brachial Artery; C-Peptide; Diabetes Mellitus, Type 1; Echocardiography, Doppler; Endothelium, Vascular; Female; Forearm; Heart Rate; Hemodynamics; Humans; Insulin; Male; Regional Blood Flow; Vasodilation | 2001 |
Beta-cell function in new-onset type 1 diabetes and immunomodulation with a heat-shock protein peptide (DiaPep277): a randomised, double-blind, phase II trial.
Type 1 diabetes results from autoimmune destruction of insulin-producing pancreatic beta cells. The 60 kDa heat-shock protein (hsp60) is one of the known target self antigens. An immunomodulatory peptide from hsp60, p277, arrested beta-cell destruction and maintained insulin production in newly diabetic NOD mice. We did a randomised, double-blind, phase II study of peptide treatment in patients with newly diagnosed (<6 months) type 1 diabetes.. 35 patients with type 1 diabetes and basal C-peptide concentrations above 0.1 nmol/L were assigned subcutaneous injections of 1 mg p277 and 40 mg mannitol in vegetable oil (DiaPep277; n=18) at entry, 1 month, and 6 months, or three placebo injections (mannitol in vehicle; placebo; n=17). The primary endpoint was glucagon-stimulated C-peptide production. Secondary endpoints were metabolic control and T-cell autoimmunity to hsp60 and to p277 (assayed by cytokine secretion). 31 patients completed 10 months of follow-up and were included in the intention-to-treat analysis.. At 10 months, mean C-peptide concentrations had fallen in the placebo group (n=16) but were maintained in the DiaPep277 group (n=15; 0.26 [SD 0.11] vs 0.93 [0.35] nmol/L; p=0.039). Need for exogenous insulin was higher in the placebo than in the DiaPep277 group (0.67 [0.33] vs 0.43 [0.17] U/kg; p=0.042). Haemoglobin A1c concentrations were low (around 7%) in both groups. T-cell reactivity to hsp60 and p277 in the DiaPep277 group showed an enhanced T-helper-2 cytokine phenotype. No adverse effects were noted.. Although this study was small, treatment of newly diagnosed type 1 diabetes with DiaPep277 seems to preserve endogenous insulin production, perhaps through induction of a shift from T-helper-1 to T-helper-2 cytokines produced by the autoimmune T cells. Topics: Adult; C-Peptide; Chaperonin 60; Diabetes Mellitus, Type 1; Double-Blind Method; Heat-Shock Proteins; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Interleukins; Islets of Langerhans; Male; Peptide Fragments; Treatment Outcome | 2001 |
Ingested IFN-alpha preserves residual beta cell function in type 1 diabetes.
Type 1 diabetes mellitus is a chronic disorder that presumably results from an autoimmune destruction of the insulin-producing pancreatic beta cells. The therapeutic potential of interventions aimed at preventing type 1 diabetes can be assessed in newly diagnosed patients. Because there is a historical experience of a low incidence of spontaneous remission in type 1 diabetes mellitus, interventions preserving beta cell function have been used to identify positive therapeutic outcomes. We treated 10 newly diagnosed type 1 diabetes patients with 30,000 IU ingested interferon-alpha (IFN-alpha) within 1 month of diagnosis and examined the difference between baseline and Sustacal-induced (Mead Johnson Nutritionals, Evansville, IN) C-peptide responses, respectively, at 0, 3, 6, 9, and 12 months. Eight of the ten patients showed preserved beta cell function, with at least a 30% increase in stimulated C-peptide levels at 0, 3, 6, 9, and 12 months after initiation of treatment. There was no discernible chemical or clinical toxicity associated with ingested IFN-alpha. Our results support the potential of ingested IFN-alpha to preserve residual beta cell function in recent onset type 1 diabetes mellitus and the testing of IFN-alpha in a placebo-controlled trial. Topics: Administration, Oral; Adolescent; Adult; Autoantibodies; C-Peptide; Cells, Cultured; Child; Cytokines; Diabetes Mellitus, Type 1; Humans; Insulin; Interferon-alpha; Islets of Langerhans; Kinetics; Treatment Outcome | 2001 |
Insulin and glucagon secretion in patients with slowly progressing autoimmune diabetes (LADA).
To metabolically characterize patients with slowly progressing autoimmune diabetes (LADA) of short duration we measured insulin, C peptide, and glucagon responses to glucose and arginine at three blood glucose levels (fasting and 14 and 28 mmol/L) in 11 patients with LADA, 11 patients with type 2 diabetes, and 14 healthy control subjects matched for age and body mass index. The acute insulin response to arginine was impaired in LADA vs. type 2 diabetes at all glucose levels, with the greatest impairment in the maximally stimulated insulin concentrations (P<0.04). In contrast, beta-cell sensitivity to glucose was unaltered in LADA and type 2 diabetes. The glucagon concentrations were elevated in both LADA and type 2 diabetic patients compared with healthy control subjects (P<0.02), but did not differ between the diabetic groups. In conclusion, patients with LADA share insulin resistance with type 2 diabetic patients, but display a more severe defect in maximally stimulated beta-cell capacity than patients with type 2 diabetes. Topics: Adult; Arginine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glucose; Humans; Insulin; Male | 2000 |
Autoantibody recognition of COOH-terminal epitopes of GAD65 marks the risk for insulin requirement in adult-onset diabetes mellitus.
Some type 2 diabetic subjects develop secondary failure to sulphonylurea treatment and require insulin therapy. To test the diagnostic sensitivity and specificity of epitopes of GAD65 autoantibodies (GAD65Ab) for insulin requirement, in patients with latent autoimmune diabetes of the adult, we studied 569 adult subjects with a clinical diagnosis of type 2 diabetes mellitus. All the patients had been initially treated with hypoglycemic agents and/or diet for at least 1 yr. The presence of GAD65Ab (61/569, 10.7%) depended on insulin therapy (P<0.0001), low BMI (P<0.0001), and low basal C-peptide (P = 0.01). The majority of GAD65Ab-positive subjects (47/61, 77%) had antibodies directed to both middle (GAD65-MAb) and COOH-terminal (GAD65-CAb) epitopes. However, GAD65-CAb were more frequent in insulin-treated subjects (92% of GAD65Ab+ individuals) than in subjects treated with hypoglycemic agents and/or diet (18.2% of GAD65Ab+ individuals), while the exclusive presence of GAD65-MAb was more frequent in subjects treated with hypoglycemic agents and/or diet (81.8% vs. 8%) (P<0.0001). The presence of GAD65-CAb had a diagnostic specificity for insulin requirement as high as 99.4% (compared with 96.9% of GAD65Ab as measured in the traditional radiobinding assay) and identified a subgroup of patients with low BMI, low basal C-peptide values, and a need for insulin therapy. Subjects carrying only GAD65-MAb were phenotypically indistinguishable from GAD65Ab-negative patients. Patients positive for GAD65-M+CAb, but not those positive for GAD65-MAb only, showed an increased risk for thyroid autoimmunity, as revealed by the presence of thyroid peroxidase autoantibodies. Our study demonstrates that the use of epitope-specific antibody assays improves the diagnostic specificity of GAD65Ab, and that the presence of GAD65Ab binding to COOH-terminal epitopes is strongly associated with a need for insulin requirement. Topics: Adult; Aged; Autoantibodies; Biomarkers; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Epitopes; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Insulin; Iodide Peroxidase; Isoenzymes; Italy; Male; Middle Aged; Risk Factors; Time Factors | 2000 |
Effects of proinsulin C-peptide on nitric oxide, microvascular blood flow and erythrocyte Na+,K+-ATPase activity in diabetes mellitus type I.
This study was conducted to evaluate the influence of proinsulin C-peptide on erythrocyte Na(+),K(+)-ATPase and endothelial nitric oxide synthase activities in patients with type I diabetes. In a randomized double-blind study design, ten patients with type I diabetes received intravenous infusions of either human C-peptide or physiological saline on two different occasions. C-peptide was infused at a rate of 3 pmol.min(-1).kg(-1) for 60 min, and thereafter at 10 pmol.min(-1).kg(-1) for 60 min. At baseline and after 60 and 120 min, laser Doppler flow (LDF) was measured following acetylcholine iontophoresis or mild thermal stimulation (44 degrees C), and venous blood samples were collected to determine plasma cGMP levels and erythrocyte membrane Na(+),K(+)-ATPase activity. The LDF response to acetylcholine increased during C-peptide infusion and decreased during saline infusion [18.6+/-19.2 and -13.2+/-9.4 arbitrary units respectively; mean+/-S.E.M.; P<0.05). No significant change in LDF was observed after thermal stimulation. The baseline plasma concentration of cGMP was 5.5+/-0.6 nmol.l(-1); this rose to 6.8+/-0.9 nmol.l(-1) during C-peptide infusion (P<0.05). Erythrocyte Na(+),K(+)-ATPase activity increased from 140+/-29 nmol of P(i).h(-1).mg(-1) in the basal state to 287+/-5 nmol of P(i). h(-1).mg(-1) during C-peptide infusion (P<0.01). There was a significant linear relationship between plasma C-peptide levels and erythrocyte Na(+),K(+)-ATPase activity during the C-peptide infusion (r=0.46, P<0.01). No significant changes in plasma cGMP levels or Na(+),K(+)-ATPase activity were observed during saline infusion. This study demonstrates an effect of human proinsulin C-peptide on microvascular function, which might be mediated by an increase in NO production and an activation of the erythrocyte Na(+),K(+)-ATPase. These mechanisms are compatible with the previous observed microvascular effects of C-peptide in patients with type I diabetes. Topics: Acetylcholine; Adult; C-Peptide; Cross-Over Studies; Cyclic GMP; Diabetes Mellitus, Type 1; Double-Blind Method; Erythrocytes; Female; Hot Temperature; Humans; Laser-Doppler Flowmetry; Linear Models; Male; Microcirculation; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Regional Blood Flow; Sodium-Potassium-Exchanging ATPase; Statistics, Nonparametric | 2000 |
Effects of portal versus systemic venous drainage in kidney-pancreas recipients.
A randomized study of combined kidney-pancreas transplantation was performed on 30 insulin-dependent diabetic patients with end-stage renal disease to compare the consequences of pancreas transplantation with portal venous (PV) and systemic venous (SV) drainage. Fourteen patients (SV) group) received systemically drained and sixteen (PV group) portally drained pancreas allografts. Enteric drainage was performed in both groups. The routine follow-up included documentation of the clinical course and detailed endocrine studies. At 1 year after transplantation, the patient survival rate was 92% for the SV group and 96% for the PV group; the graft survival rate was 78% and 82%, respectively. Endocrine studies indicated no difference in fasting and stimulated glucose or in glycosylated hemoglobin between the two groups. In addition, no hyperinsulinemia and lipidic abnormalities were evidenced in either group Long-term studies are required to conclude whether PV and SV drainage in pancreas transplantation are equivalent in terms of patient and graft survival as well as metabolic consequences. Topics: Adult; Anastomosis, Surgical; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drainage; Female; Glucose Tolerance Test; Humans; Insulin; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Portal Vein; Triglycerides; Veins | 2000 |
Beneficial effects of C-peptide on incipient nephropathy and neuropathy in patients with Type 1 diabetes mellitus.
Recent studies have indicated that proinsulin C-peptide shows specific binding to cell membrane binding sites and may exert biological effects when administered to patients with Type 1 diabetes mellitus. This study was undertaken to determine if combined treatment with C-peptide and insulin might reduce the level of microalbuminuria in patients with Type 1 diabetes and incipient nephropathy.. Twenty-one normotensive patients with microalbuminuria were studied for 6 months in a double-blind, randomized, cross-over design. The patients received s.c. injections of either human C-peptide (600 nmol/24 h) or placebo plus their regular insulin regimen for 3 months.. Glycaemic control improved slightly during the study and to a similar extent in both treatment groups. Blood pressure was unaltered throughout the study. During the C-peptide treatment period, urinary albumin excretion decreased progressively on average from 58 microg/min (basal) to 34 microg/min (3 months, P < 0.01) and it tended to increase, but not significantly so, during the placebo period. The difference between the two treatment periods was statistically significant (P < 0.01). In the 12 patients with signs of autonomic neuropathy prior to the study, respiratory heart rate variability increased by 21 +/- 9% (P < 0.05) during treatment with C-peptide but was unaltered during placebo. Thermal thresholds were significantly improved during C-peptide treatment in comparison to placebo (n = 6, P < 0.05).. These results indicate that combined treatment with C-peptide and insulin for 3 months may improve renal function by diminishing urinary albumin excretion and ameliorate autonomic and sensory nerve dysfunction in patients with Type 1 diabetes mellitus. Topics: Adult; Albuminuria; Autonomic Nervous System Diseases; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Double-Blind Method; Heart Rate; Humans; Insulin; Kidney; Placebos | 2000 |
Effects of nicotinamide and intravenous insulin therapy in newly diagnosed type 1 diabetes.
To investigate the effect of intravenous insulin therapy combined with nicotinamide in the metabolic control and beta-cell function of newly diagnosed type 1 diabetic subjects in comparison with intensive insulin therapy and nicotinamide alone.. A total of 34 newly diagnosed type 1 diabetic patients were included. After the correction of initial metabolic disturbances, subjects were randomly assigned to the following three groups within 72 h after admission: 1) intensive insulin therapy + placebo (C) (n = 12); 2) intensive insulin therapy + nicotinamide, 700 mg three times a day (NIC) (n = 11); and 3) 72-h intravenous insulin followed by intensive insulin therapy + nicotinamide, 700 mg three times a day (NIV) (n = 11). The subjects were monitored for 12 months. GAD, tyrosine phosphatase antibodies, and insulin autoantibodies were measured. C-peptide was measured basally and after 2, 4, 6, 8, and 10 min of 1 mg intravenous glucagon. HbA1c, glucagon, and antibody measurements were determined initially and at 1, 3, 6, 9, and 12 months.. HbA1c values declined to normal after treatment was initiated in all groups and remained not significantly different during the follow-up period. We did not find differences between experimental (NIC and NIV) and placebo (C) groups in terms of beta-cell function, considering basal or glucagon-stimulated C-peptide (maximal stimulated C-peptide and area under the curve [AUC] of C-peptide) values during the follow-up period. After pooling data from the NIC and NIV groups (both including nicotinamide) and comparing it with data from the C group, the results remained unchanged. At diagnosis, GAD positivity was observed in 10 of 12, 8 of 11, and 10 of 11 subjects (NS) in the C, NIC, and NIV groups, respectively, and IA2 positivity was observed in 3 of 12, 4 of 11, and 4 of 11 subjects (NS) in the C, NIC, and NIV groups, respectively. Antibody titers displayed a similar behavior in all groups during the follow-up period.. Our pilot study failed to demonstrate that the addition of 72-h intravenous insulin and nicotinamide to conventional intensive insulin therapy produces any beneficial effect in newly diagnosed type 1 diabetic subjects in terms of beta-cell function and metabolic control. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Injections, Intravenous; Insulin; Insulin Infusion Systems; Islets of Langerhans; Male; Niacinamide; Pilot Projects; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Time Factors | 2000 |
Clinical parameters (body mass index and age) are the best predictors for the need of insulin therapy during the first 18 months of diabetes mellitus in young adult patients.
To address the question whether there are simple clinical predictors of need for insulin in the first 18 months of treatment of diabetes presenting in young adult subjects, a prospective study of 24 patients with diabetes mellitus (age: 18-40 years) was designed. At diagnosis of diabetes, age, sex, body mass index (BMI), glycemia, ketonuria, C-peptide, insulin autoantibodies, islet cell antibodies and glutamic acid decarboxylase antibodies were recorded before starting any treatment. At the end of the follow-up (18 +/- 4 months), they were divided into two groups according to their need for insulin therapy: group 1 (n=15; 62%), who needed insulin therapy, and group 2 (n=9; 38%), who did not. Each marker was related to actual need for therapy necessity. Multivariate analysis showed that BMI and age were the variables with greatest predictive value regarding need for insulin. These data reveal that the need for insulin therapy in young adult diabetic patients may be supported by the clinical criteria of age and BMI, which are both easily and quickly determined. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Biomarkers; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Islets of Langerhans; Ketones; Male; Predictive Value of Tests | 2000 |
A randomized trial of methotrexate in newly diagnosed patients with type 1 diabetes mellitus.
The aim of this study was to determine whether low-dose, oral methotrexate therapy would prolong the remission phase at the onset of Type 1 diabetes. Ten newly diagnosed, nonacidotic, ICA-positive, Type 1 diabetics were randomly assigned to receive either methotrexate (5 mg/m(2)/week) or no immunosuppressive treatment. The study was not blinded and no placebo was given. Endogenous insulin production was assessed every 3 months by fasting and Sustacal-stimulated C-peptide levels. Methotrexate therapy was not beneficial in prolonging islet survival as assessed by fasting and stimulated C-peptide levels. Insulin requirements were generally lower in the control group, and islet failure, determined by an insulin requirement of >0.7 u/kg/day, occurred earlier for those receiving MTX (P < 0.02). Side effects of methotrexate treatment were minimal. There was no benefit from methotrexate therapy, and methotrexate therapy was associated with an earlier increase in insulin requirements. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Glycated Hemoglobin; Humans; Insulin; Liver; Male; Methotrexate | 2000 |
Islet transplantation in seven patients with type 1 diabetes mellitus using a glucocorticoid-free immunosuppressive regimen.
Registry data on patients with type 1 diabetes mellitus who undergo pancreatic islet transplantation indicate that only 8 percent are free of the need for insulin therapy at one year.. Seven consecutive patients with type 1 diabetes and a history of severe hypoglycemia and metabolic instability underwent islet transplantation in conjunction with a glucocorticoid-free immunosuppressive regimen consisting of sirolimus, tacrolimus, and daclizumab. Islets were isolated by ductal perfusion with cold, purified collagenase, digested and purified in xenoprotein-free medium, and transplanted immediately by means of a percutaneous transhepatic portal embolization.. All seven patients quickly attained sustained insulin independence after transplantation of a mean (+/-SD) islet mass of 11,547+/-1604 islet equivalents per kilogram of body weight (median follow-up, 11.9 months; range, 4.4 to 14.9). All recipients required islets from two donor pancreases, and one required a third transplant from two donors to achieve sustained insulin independence. The mean glycosylated hemoglobin values were normal after transplantation in all recipients. The mean amplitude of glycemic excursions (a measure of fluctuations in blood glucose concentrations) was significantly decreased after the attainment of insulin independence (from 198+/-32 mg per deciliter [11.1+/-1.8 mmol per liter] before transplantation to 119+/-37 mg per deciliter [6.7+/-2.1 mmol per liter] after the first transplantation and 51+/-30 mg per deciliter [2.8+/-1.7 mmol per liter] after the attainment of insulin independence; P<0.001). There were no further episodes of hypoglycemic coma. Complications were minor, and there were no significant increases in lipid concentrations during follow-up.. Our observations in patients with type 1 diabetes indicate that islet transplantation can result in insulin independence with excellent metabolic control when glucocorticoid-free immunosuppression is combined with the infusion of an adequate islet mass. Topics: Adult; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Blood Glucose; C-Peptide; Daclizumab; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Immunoglobulin G; Immunosuppressive Agents; Insulin; Islets of Langerhans Transplantation; Middle Aged; Sirolimus; Tacrolimus; Transplantation Conditioning | 2000 |
Oral insulin administration and residual beta-cell function in recent-onset type 1 diabetes: a multicentre randomised controlled trial. Diabète Insuline Orale group.
Oral administration of autoantigens can slow the progression of beta-cell destruction in non-obese diabetic mice. We investigated whether oral administration of recombinant human insulin could protect residual beta-cell function in recent-onset type 1 diabetes.. We enrolled 131 autoantibody-positive diabetic patients aged 7-40 years within 2 weeks of diagnosis (no ketoacidosis at diagnosis, weight loss <10%, polyuria for <6 weeks). They were randomly assigned 2.5 mg or 7.5 mg oral insulin daily or placebo for 1 year, in addition to subcutaneous insulin therapy. Serum C-peptide concentrations were measured in the fasting state and after stimulation, to assess beta-cell function. Autoantibodies to beta-cell antigens were assayed. Analyses were by intention to treat.. Baseline C-peptide and haemoglobin A1c concentrations were similar in the three groups. During follow-up, there were no differences between the groups assigned 2.5 mg or 7.5 mg oral insulin or placebo in subcutaneous insulin requirements, haemoglobin A1c concentrations, or measurements of fasting (mean at 12 months 0.18 [SD 0.17], 0.17 [0.17], and 0.17 [0.12] nmol/L) or stimulated C-peptide concentrations (glucagon-stimulated 0.39 [0.38], 0.37 [0.39], and 0.33 [0.24] nmol/L; meal-stimulated 0.72 [0.60], 0.49 [0.49], and 0.57 [0.51 nmol/L]. Neither age nor C-peptide concentration at entry influenced treatment effects. No differences were seen in the time-course or titres of antibodies to insulin, glutamic acid decarboxylase, or islet antigen 2.. At the doses used in this trial, oral administration of insulin initiated at clinical onset of type 1 diabetes did not prevent the deterioration of beta-cell function. Topics: Administration, Oral; Adolescent; Adult; Autoantibodies; Autoimmune Diseases; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Recombinant Proteins | 2000 |
No effect of oral insulin on residual beta-cell function in recent-onset type I diabetes (the IMDIAB VII). IMDIAB Group.
Induction of tolerance to insulin is achievable in animal models of Type I (insulin-dependent) Diabetes mellitus by oral treatment with this hormone, which can lead to prevention of the disease. In the Diabetes Prevention Trial of Type I diabetes (DPT-1), oral insulin is given with the aim of preventing disease insurgence. We investigated whether if given at diagnosis of Type I diabetes in humans, oral insulin can still act as a tolerogen and therefore preserve residual beta-cell function, which is known to be substantial at diagnosis.. A double-blind trial was carried out in patients (mean age +/- SD: 14 +/- 8 years) with recent-onset Type I diabetes to whom oral insulin (5 mg daily) or placebo was given for 12 months in addition to intensive subcutaneous insulin therapy. A total of 82 patients with clinical Type I diabetes ( < 4 weeks duration) were studied. Basal C peptide and glycated haemoglobin were measured and the insulin requirement monitored every 3 months up to 1 year. Insulin antibodies were also measured in 27 patients treated with oral insulin and in 18 patients receiving placebo at the beginning of the trial and after 3, 6 and 12 months of treatment.. The trial was completed by 80 patients. Overall and without distinction between age at diagnosis, at 3, 6, 9 and 12 months baseline mean C-peptide secretion in patients treated with oral insulin did not differ from that of those patients treated with placebo. In patients younger than 15 years a tendency for lower C-peptide values at 9 and 12 months was observed in the oral insulin group. Insulin requirement at 1 year was similar between the two groups as well as the percentage of glycated haemoglobin. Finally, IgG insulin antibodies were similar in the two groups at each time point.. The results of this study indicate that the addition of 5 mg of oral insulin does not modify the course of the disease in the first year after diagnosis and probably does not statistically affect the humoral immune response against insulin. Topics: Administration, Oral; Adolescent; Adult; Age of Onset; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Islets of Langerhans; Italy; Male | 2000 |
Serum C-peptide concentrations poorly phenotype type 2 diabetic end-stage renal disease patients.
A homogeneous patient population is necessary to identify genetic factors that regulate complex disease pathogenesis. In this study, we evaluated clinical and biochemical phenotyping criteria for type 2 diabetes in end-stage renal disease (ESRD) probands of families in which nephropathy is clustered. C-peptide concentrations accurately discriminate type 1 from type 2 diabetic patients with normal renal function, but have not been extensively evaluated in ESRD patients. We hypothesized that C-peptide concentrations may not accurately reflect insulin synthesis in ESRD subjects, since the kidney is the major site of C-peptide catabolism and would poorly correlate with accepted clinical criteria used to classify diabetics as types 1 and 2.. Consenting diabetic ESRD patients (N = 341) from northeastern Ohio were enrolled. Clinical history was obtained by questionnaire, and predialysis blood samples were collected for C-peptide levels from subjects with at least one living diabetic sibling (N = 127, 48% males, 59% African Americans).. Using clinical criteria, 79% of the study population were categorized as type 1 (10%) or type 2 diabetics (69%), while 21% of diabetic ESRD patients could not be classified. In contrast, 98% of the patients were classified as type 2 diabetics when stratified by C-peptide concentrations using criteria derived from the Diabetes Control and Complications Trial Research Group (DCCT) and UREMIDIAB studies. Categorization was concordant in only 70% of ESRD probands when C-peptide concentration and clinical classification algorithms were compared. Using clinical phenotyping criteria as the standard for comparison, C-peptide concentrations classified diabetic ESRD patients with 100% sensitivity, but only 5% specificity. The mean C-peptide concentrations were similar in diabetic ESRD patients (3.2 +/- 1.9 nmol/L) and nondiabetic ESRD subjects (3.5 +/- 1.7 nmol/L, N = 30, P = NS), but were 2.5-fold higher compared with diabetic siblings (1.3 +/- 0.7 nmol/L, N = 30, P < 0.05) with normal renal function and were indistinguishable between type 1 and type 2 diabetics. Although 10% of the diabetic ESRD study population was classified as type 1 diabetics using clinical criteria, only 1.5% of these patients had C-peptide levels less than 0.20 nmol/L, the standard cut-off used to discriminate type 1 from type 2 diabetes in patients with normal renal function. However, the criteria of C-peptide concentrations> 0.50 nmol/L and diabetes onset in patients who are more than 38 years old identify type 2 diabetes with a 97% positive predictive value in our ESRD population.. Accepted clinical criteria, used to discriminate type 1 and type 2 diabetes, failed to classify a significant proportion of diabetic ESRD patients. In contrast to previous reports, C-peptide levels were elevated in the majority of type 1 ESRD diabetic patients and did not improve the power of clinical parameters to separate them from type 2 diabetic or nondiabetic ESRD subjects. Accurate classification of diabetic ESRD patients for genetic epidemiological studies requires both clinical and biochemical criteria, which may differ from norms used in diabetic populations with normal renal function. Topics: Adult; Age of Onset; Algorithms; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Genetic Predisposition to Disease; Humans; Insulin; Insulin Secretion; Kidney Failure, Chronic; Male; Middle Aged; Phenotype; Predictive Value of Tests; Sensitivity and Specificity | 2000 |
A 16-week comparison of the novel insulin analog insulin glargine (HOE 901) and NPH human insulin used with insulin lispro in patients with type 1 diabetes.
To determine the safety and efficacy of the long-acting insulin analog, insulin glargine, as a component of basal bolus therapy in patients with type 1 diabetes.. Patients with type 1 diabetes receiving basal-bolus insulin treatment with NPH human insulin and insulin lispro were randomized to receive insulin glargine (HOE 901), a long-acting basal insulin analog, once a day (n = 310) or NPH human insulin (n = 309) as basal treatment with continued bolus insulin lispro for 16 weeks in an open-label study NPH insulin patients maintained their prior schedule of administration once or twice a day, whereas insulin glargine patients received basal insulin once a day at bedtime.. Compared with all NPH insulin patients, insulin glargine patients had significant decreases in fasting blood glucose measured at home (means +/- SEM, -42.0 +/- 4.7 vs. -12.4 +/- 4.7 mg/dl [-2.33 +/- 0.26 vs. -0.69 +/- 0.26 mmol/l]; P = 0.0001). These differences were evident early and persisted throughout the study More patients in the insulin glargine group (29.6%) than in the NPH group (16.8%) reached a target fasting blood glucose of 119 mg/dl (< 6.6 mmol/l). However, there were no differences between the groups with respect to change in GHb. Insulin glargine treatment was also associated with a significant decrease in the variability of fasting blood glucose values (P = 0.0124). No differences in the occurrence of symptomatic hypoglycemia, including nocturnal hypoglycemia, were observed. Overall, adverse events were similar in the two treatment groups with the exception of injection site pain, which was more common in the insulin glargine group (6.1%) than in the NPH group (0.3%). Weight gain was 0.12 kg in insulin glargine patients and 0.54 kg in NPH insulin patients (P = 0.034).. Basal insulin therapy with insulin glargine once a day appears to be as safe and at least as effective as using NPH insulin once or twice a day in maintaining glycemic control in patients with type 1 diabetes receiving basal-bolus insulin treatment with insulin lispro. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Drug Therapy, Combination; Ethnicity; Fasting; Female; Humans; Hypoglycemia; Insulin; Insulin Glargine; Insulin Lispro; Insulin, Isophane; Insulin, Long-Acting; Male; United States | 2000 |
Physiological responses during hypoglycaemia induced by regular human insulin or a novel human analogue, insulin glargine.
Glargine, a product of recombinant technology, has different structural and physicochemical properties compared with native human insulin. We determined whether such differences are associated with alterations in the responses to hypoglycaemia induced by glargine.. Nineteen adults (six healthy and 13 with type 1 diabetes) underwent a 5-h hyperinsulinaemic (2 mU/kg/min(-1)) stepped hypoglycaemic clamps (hourly targets of 4.7, 4.2, 3.6, 3.1 and 2.5 mmol/l, respectively) on two occasions using intravenous infusion of regular human insulin or glargine, in random sequence. Hypoglycaemic symptoms, counter-regulatory hormones and glucose disposal rates were assessed at intervals throughout the clamps. A 1-week 'wash out' period was observed between studies.. The peak total symptoms scores (mean +/- s.e.m.) at nadir blood glucose (2.5 mmol/1) were 18.83 +/- 2.68 (healthy) and 17.46 +/- 3.62 (diabetic) during regular insulin, and 18.50 +/- 3.20 (healthy) and 19.08 +/- 3.83 (diabetic) during glargine infusion. The peak epinephrine levels during hypoglycaemia were 767.8 +/- 140.4 pg/ml (regular insulin) and 608.8 +/- 129.9 pg/ml (glargine) among healthy subjects, and 332.5 +/- 54.8 pg/ml (regular insulin) and 321.8 +/- 67.4 pg/ml (glargine) in diabetic patients. Diabetic patients had blunted glucagon responses during hypoglycaemia with either insulin. Both insulins also elicited similar rates of glucose disposal.. We conclude that insulin glargine and regular human insulin elicit comparable symptomatic and counter-regulatory hormonal responses during hypoglycaemia in healthy or diabetic subjects, and induce similar rates of glucose disposal. Since glargine is designed for subcutaneous (s.c.) use, it is possible (though unlikely) that our findings obtained using an intravenous protocol could differ from responses to hypoglycaemia induced by the s.c. route. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Epinephrine; Female; Glucagon; Glucose Clamp Technique; Heart Rate; Human Growth Hormone; Humans; Hydrocortisone; Hyperinsulinism; Hypoglycemia; Insulin; Insulin Glargine; Insulin, Long-Acting; Male; Norepinephrine; Recombinant Proteins; Reference Values | 2000 |
Diabetes-associated autoantibodies in relation to clinical characteristics and natural course in children with newly diagnosed type 1 diabetes. The Childhood Diabetes In Finland Study Group.
We analyzed 747 children, younger than 15 yr of age, with newly diagnosed diabetes, for antibodies to glutamic acid decarboxylase (GADA), the IA-2 protein (IA-2A), insulin (IAA), and islet cells, to evaluate the influence of positivity for GADA, IA-2A, IAA, or multiple (> or = 3) autoantibodies at diagnosis, on the clinical presentation and natural course of the disease over the first 2 yr and to characterize autoantibody-negative patients. At diagnosis, 73.2% of the children tested positive for GADA, 85.7% for IA-2A, 54.2% for IAA, and 72.6% for multiple autoantibodies. Only 17 subjects (2.3%) had no detectable autoantibodies. The patients testing positive for multiple autoantibodies were younger than the remaining children (P < 0.001). A similar age difference was seen when comparing IAA-positive and -negative patients (P < 0.001). There was no significant difference between the GADA-positive and -negative subjects in the degree of metabolic decompensation at diagnosis, whereas those testing positive for IA-2A had reduced serum C-peptide concentrations (P = 0.003), and those positive for IAA had lower glycated hemoglobin values. The patients with no detectable autoantibodies had higher serum C-peptide levels (P = 0.007) at diagnosis than did the other subjects. The children initially positive for IA-2A had decreased serum C-peptide concentrations at 24 months (P = 0.045), and their daily insulin dose was higher at 18 (P = 0.005) and 24 months (P < 0.001). The patients who tested positive for multiple autoantibodies at diagnosis had decreased serum C-peptide levels (P < 0.001) and higher insulin doses (P = 0.005) at 12, 18, and 24 months. A lower proportion of them were also in clinical remission at 12 and 18 months (P = 0.01). Autoantibody-negative subjects needed less exogenous insulin at 6 and 18 (P = 0.01) and at 24 months (P < 0.001) than the other subjects, and a higher proportion of them were in clinical remission at 18 months (P < 0.001). We conclude that positivity for multiple diabetes-related autoantibodies is associated with accelerated beta-cell destruction and an increased requirement for exogenous insulin over the second year of clinical disease, indicating that multiple autoantibodies reflect an aggressive progression to total beta-cell destruction. Patients testing negative for diabetes-associated autoantibodies at diagnosis seem to have a milder degree of beta-cell destruction, but their metabolic decompensation is similar to that seen Topics: Adolescent; Autoantibodies; Autoantigens; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Infant; Insulin; Islets of Langerhans; Male; Membrane Proteins; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Sex Factors | 1999 |
Lispro or regular insulin for multiple injection therapy in adolescence. Differences in free insulin and glucose levels overnight.
Regular insulin given with the evening meal could contribute to the risk of nocturnal hypoglycemia in adolescents with type 1 diabetes using a multiple injection regimen. To test this hypothesis, we compared glucodynamics and free insulin levels on two separate study nights.. A total of 14 adolescents were recruited. On both nights, identical doses of regular insulin or insulin lispro were administered 30 min or 10 min, respectively, before the evening meal, using a double-blind randomized crossover study design. Doses of NPH insulin and carbohydrate content of the evening meal and snack were kept identical. Blood samples were taken every 15 min for blood glucose and every 60 min for free insulin and ketones.. After insulin lispro administration, glucose levels were significantly lower between the evening meal and the bedtime snack (analysis of variance [ANOVA] P = 0.02), and four hypoglycemic episodes were recorded. This corresponded to a higher (458 +/- 48 vs. 305 +/- 33 pmol/l, P = 0.02), earlier (64 +/- 4.6 vs. 103 +/- 12 min, P = 0.01), and shorter-lasting (245 +/- 21 vs. 365 +/- 39 min, P = 0.01) insulin peak in contrast to regular insulin. After the bedtime snack, glucose levels increased dramatically during the lispro night and stayed higher, up to 0300 in the morning (ANOVA P = 0.01), corresponding to lower mean insulin levels (146 +/- 20 vs. 184 +/- 27 pmol/l, P = 0.04). No differences were seen in glucose and insulin levels between 0300 and 0800. Four episodes of nocturnal hypoglycemia were documented after the bedtime snack during the regular insulin night, in contrast to one episode after insulin lispro. No differences in ketone levels were observed.. The replacement of regular insulin with insulin lispro may reduce the risk of late hypoglycemia, but redistribution of the evening carbohydrate may be needed to ensure good metabolic control and prevent early postprandial hypoglycemia. Topics: Activity Cycles; Adolescent; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Eating; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Lispro; Insulin, Isophane; Ketones; Life Tables; Male; Postprandial Period | 1999 |
Lipophilic thiamine treatment in long-standing insulin-dependent diabetes mellitus.
Thiamine plays an important role in the regulation of glucose metabolism and pancreatic beta-cell functioning. A role for this vitamin in cellular glucose transport has been indicated in the literature. The aim of this study was to determine whether a lipophilic form of thiamine (benzoyloxymethyl-thiamine, BOM) was able to improve metabolic control in patients with long-standing insulin-dependent diabetes mellitus (type 1). A total of 10 children with type 1 diabetes of long duration (age 11.4 +/- 1.2 years, duration of the disease 4.5 +/- 0.7 years, means +/- SEM) were studied before and after treatment with BOM in a randomized double-blind and placebo-controlled study. Five patients were assigned to the BOM-treated group and five to the placebo-group. In all patients basal and glucagon-stimulated C-peptide secretion was undetectable. Thiamine status was assayed by measuring the plasma content of thiamine and its monophosphate form at entry and after 3 months of treatment. The blood HbA(1C) levels and the daily dose of insulin per kg body weight were assessed in both groups before treatment, after 1 month and 3 months of treatment, then 3 months following its suspension. The plasma content of thiamine + thiamine monophosphate in type 1 diabetic patients (35.3 +/- 3.6 pmol/mL) was significantly lower when compared with that measured in six age-matched normal subjects (53.2 +/- 2.3 pmol/mL, P < 0.05). Topics: Adolescent; Age of Onset; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Glucagon; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Placebos; Reference Values; Thiamine; Thiamine Monophosphate; Time Factors | 1999 |
Sodium transport kinetics, cell membrane lipid composition, neural conduction and metabolic control in type 1 diabetic patients. Changes after a low-dose n-3 fatty acid dietary intervention.
A decreased content of n-3 fatty acids in erythrocyte membrane of type 1 diabetic patients, which is inversely related to plasma levels of HbA(1c), has been reported previously. Our aim in this study was to observe the changes after a low-dose n-3 fatty acid (330 mg/day docosahexaenoic acid and 630 mg/day eicosapentanoic acid) dietary intervention in the lipid composition of cell membrane and metabolic control (measured according to plasma HbA(1c) levels). Since changes in both parameters may alter transmembrane sodium transport or influence parameters measuring target organ damage, we also studied the neural conduction quality and activity of four sodium transporters.. Eighteen type 1 diabetic patients were randomly assigned to continue their usual diet (control group) or to supplement their diet with a daily low dose of n-3 fatty acids (supplemented group). The changes between baseline and end values of the following parameters were compared: HbA(1c), lipid and phospholipid composition of cell membrane, activity of four ion carriers and neural conduction quality.. The dietary supplementation caused statistically significant changes in membrane lipid composition, particularly an increase of C22:6 (n-3) and the total n-3 fatty acid (respectively +0.90+/-1.14% vs. -0.44+/-1.23% and +1.36+/-1.62% vs. -0.5+/-1.80%, p<0.05). After the dietary supplementation, we also observed a significant decrease of HbA(1c) (-2.00+/-1.9% vs. -0.13+/-0.48%, p<0.05), without significant changes in the dose of insulin required, an increase in the motor conduction velocity by the median nerve (+2.12 +/-1.35 m/s vs. -0.8+/-2.34 m/s, p<0.05) and a decrease of the V(max) of the Na(+)-Li(+) countertransport (-96.6+/-111.2 vs. +58.1+/-81.3 micromol/l cell/h(-1), p<0.01).. A low-dose omega-3 fatty acid dietary supplementation may change the fatty acid composition of the cell membrane and improve the metabolic control of diabetes. Using this dose, we also observed a decrease of the maximal rate of Na(+)-Li(+) countertransport and a slight improvement of neural conduction. Topics: Adolescent; Adult; Biological Transport; Blood Glucose; Body Mass Index; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Erythrocytes; Fatty Acids; Fatty Acids, Omega-3; Female; Hemoglobin A; Humans; Insulin; Male; Membrane Lipids; Neural Conduction; Prospective Studies; Sodium | 1999 |
Effect of Bacillus Calmette-Guerin vaccination on new-onset type 1 diabetes. A randomized clinical study.
We undertook this study to test whether Bacillus Calmette-Guerin (BCG) vaccine preserves beta-cell function and increases the remission rate in children with new-onset type 1 diabetes.. This was a randomized double-blind placebo-controlled trial offered to children referred to the Barbara Davis Center for Childhood Diabetes or the Baystate Medical Center with a diagnosis of new-onset type 1 diabetes. There were 94 children aged 5-18 years who received either BCG or saline intradermally within 4 months of onset of symptoms and who were then evaluated at 3-month intervals for 2 years. The primary end point was remission, defined as insulin independence for 4 weeks. Secondary end points were C-peptide levels (fasting and in response to a mixed meal challenge), insulin dose, and HbA1c.. Of the patients, 47 were randomized to each arm; 7 in the placebo group and 9 in the BCG group did not complete 1 year of the study and are not included in the analysis. One patient from each group achieved remission. Fasting and stimulated C-peptide levels did not differ by treatment arm but declined in both groups and were lower initially and during the entire 2-year period in younger children. Insulin requirements and HbA1c levels did not differ in the two groups.. Vaccination with BCG at the time of onset of type 1 diabetes does not increase the remission rate or preserve beta-cell function. Topics: Adolescent; Autoantibodies; BCG Vaccine; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Eating; Female; Follow-Up Studies; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Placebos | 1999 |
Effect of intensive therapy on residual beta-cell function in patients with type 1 diabetes in the diabetes control and complications trial. A randomized, controlled trial. The Diabetes Control and Complications Trial Research Group.
Although insulin secretion is severely decreased in most patients with type 1 diabetes, levels of residual insulin secretion often vary early in the disease. The significance of residual insulin secretion with regard to metabolic control and to long-term complications and ways to preserve such secretion are not well understood.. To compare the effects of intensive and conventional therapy on residual insulin secretion in Diabetes Control and Complications Trial (DCCT) participants.. Multicenter, randomized, controlled clinical trial.. 29 DCCT clinical centers.. 855 of the 1441 DCCT participants had had type 1 diabetes for 1 to 5 years at baseline. Of these 855 patients, 303 were C-peptide responders (C-peptide level, 0.20 to 0.50 pmol/mL after ingestion of a standardized, mixed meal); 138 of these patients were randomly assigned to intensive therapy, and 165 were assigned to conventional therapy. Five hundred fifty-two patients were nonresponders (stimulated C-peptide level < 0.2 pmol/mL); 274 of these patients were assigned to intensive therapy, and 278 were assigned to conventional therapy.. 1) Intensive therapy with 3 or more insulin injections daily or continuous subcutaneous infusion of insulin, guided by 4 or more glucose tests per day or 2) conventional therapy with 1 or 2 insulin injections daily.. Stimulated C-peptide level was measured annually in responders. Development of retinopathy and microalbuminuria was assessed annually, hemoglobin A1c levels were measured quarterly, and episodes of hypoglycemia were ascertained quarterly.. Responders receiving intensive therapy maintained a higher stimulated C-peptide level and a lower likelihood of becoming nonresponders than did responders receiving conventional therapy (risk reduction, 57% [95% CI, 39% to 71%]; P < 0.001). As in the entire DCCT cohort, intensively treated responders had a reduced risk for retinopathy progression and development of microalbuminuria and a higher risk for severe hypoglycemia compared with conventionally treated responders. Among intensively treated patients, responders had a lower hemoglobin A1c value (P < 0.01), a 50% (95% CI, 12% to 72%) reduced risk for retinopathy progression, and a lower risk for severe hypoglycemia (risk reduction, 65% [CI, 53% to 74%]; P < 0.001) compared with nonresponders.. Intensive therapy for type 1 diabetes helps sustain endogenous insulin secretion, which, in turn, is associated with better metabolic control and lower risk for hypoglycemia and chronic complications. These observations underscore the importance of initiating intensive diabetic management as early as safely possible after type 1 diabetes is diagnosed. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Statistics as Topic | 1998 |
The effect of the insulin analog lispro on nighttime blood glucose control in type 1 diabetic patients.
Unmodified regular insulin has a long absorption tail, unlike the fast-acting insulin analog lispro, and may contribute to hypoglycemia in the early part of the night. A randomized crossover double-blind study was performed to compare blood glucose concentrations in the early part of the night in type 1 diabetic patients receiving lispro or unmodified regular human insulin, in random order, on 2 separate study days.. We studied 23 C-peptide-negative patients; 12 were using a premeal plus basal insulin regimen, and 11 were using twice-daily insulin injections. Patients were admitted to the investigation unit at 5:00 P.M. and received a single dose of lispro or unmodified regular human insulin before the evening meal. In both groups, the NPH insulin dose remained unchanged. Identical meals and snacks were eaten at the same time during both study days.. Average postprandial (6:00-10:00 P.M.) blood glucose concentrations were significantly lower after lispro therapy compared with human insulin (7.1 +/- 0.4 [SE] vs. 8.5 +/- 0.4 mmol/l, P = 0.0002). Nighttime (midnight to 4:00 A.M.) blood glucose concentrations were significantly higher after lispro compared with human insulin (10.3 +/- 0.4 vs. 9.1 +/- 0.4 mmol/l, P = 0.02). This difference was greatest in patients on the premeal plus basal insulin regimen (11.6 +/- 0.5 vs. 8.7 +/- 0.4 mmol/l, P < 0.001). The incidence of nocturnal hypoglycemia (midnight to 4:00 A.M., blood glucose < 3.5 mmol/l) was less with lispro compared with unmodified insulin (1 vs. 6 patients, P = 0.04). Nighttime (midnight to 4:00 A.M.) 3-hydroxybutyrate (102 +/- 13 vs. 51 +/- 7 mumol/l, P = 0.000) and glycerol (52 +/- 3 vs. 42 +/- 2 mumol/l, P < 0.01) were significantly higher after lispro therapy compared with human insulin in patients on the premeal plus bolus insulin regimen.. Lispro can improve postprandial blood glucose control and reduce the incidence of nocturnal hypoglycemia at the expense of nocturnal hyperglycemia and hyperketonemia in patients using a premeal plus basal insulin regimen. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Administration Schedule; Eating; Fasting; Female; Human Growth Hormone; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Lispro; Male; Postprandial Period | 1998 |
Induction of beta-cell rest in type 1 diabetes. Studies on the effects of octreotide and diazoxide.
To evaluate the inhibitory effects of octreotide and diazoxide on insulin secretion in patients with type 1 diabetes and measurable levels of circulating C-peptide.. Diazoxide was given to six patients during a 7-day period (100 mg three times daily), followed by a 3-week washout. Subsequently, octreotide (50 micrograms, three times daily) was administered subcutaneously for 7 days. Pre- and post- prandial blood glucose and serum C-peptide concentrations were measured before medication (control) and on day 7 of each medication period. Glucagon-stimulated C-peptide was determined in the morning before medication and on the day after each treatment period.. Diazoxide inhibited glucagon-stimulated C-peptide secretion (mean increment 0.08 nmol/l vs. 0.18 nmol/l, P < 0.05), whereas octreotide had no such effect. Both reduced the pre- and postprandial serum C-peptide concentrations (P < 0.05), octreotide being the more potent in this respect. A reduction in basal and meal-related blood glucose was observed during octreotide treatment, whereas the glucose concentrations tended to be higher during treatment with diazoxide than during the 24-h control period.. The study indicates that the two drugs reduce insulin output by different mechanisms. Diazoxide inhibits hormonal release directly on the beta-cells, whereas octreotide exerts its effect indirectly, presumably by multiple actions on insulin sensitivity and insulin-releasing hormones. The results suggest that each drug is capable of inducing beta-cell rest in type 1 diabetes. Topics: Adult; Antihypertensive Agents; Blood Glucose; C-Peptide; Data Interpretation, Statistical; Diabetes Mellitus, Type 1; Diazoxide; Female; Food; Glucagon; Glycated Hemoglobin; Hormones; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Octreotide; Postprandial Period | 1998 |
Implantation of standardized beta-cell grafts in a liver segment of IDDM patients: graft and recipients characteristics in two cases of insulin-independence under maintenance immunosuppression for prior kidney graft.
Islet allografts in insulin-dependent diabetic (IDDM) patients exhibit variable survival lengths and low rates of insulin-independence despite treatment with anti-T-cell antibodies and maintenance immunosuppression. Use of poorly characterized freshly isolated preparations makes it difficult to determine whether failures are caused by variations in donor tissue. This study assesses survival of standardized beta-cell allografts in C-peptide negative IDDM patients on maintenance immunosuppression following kidney transplantation and without receiving anti-T-cell antibodies or additional immunosuppression. Human islets were isolated from pancreatic segments after maximal 20 h cold-preservation. During culture, preparations were selected according to quality control tests and combined with grafts with standardized cell composition (> or = 50% beta cells), viability (> or = 90%), total beta-cell number (1 to 2 x 10(6)/kg body weight) and insulin-producing capacity (2 to 4 nmol x graft(-1) x h(-1)). Grafts were injected in a liver segment through the repermeabilized umbilical vein. After 2 weeks C-peptide positivity, four out of seven recipients became C-peptide negative; two of them were initially GAD65-antibody positive and exhibited a rise in titre during graft destruction. The other three patients remained C-peptide positive for more than 1 year, two of them becoming insulin-independent with near-normal fasting glycaemia and HbA1c; they remained GAD65- and islet cell antibody negative. The three patients with surviving grafts presented a history of anti-thymocyte globulin therapy at kidney transplantation. Long-term surviving grafts increased C-peptide release following intravenous glucagon or oral glucose but not following intravenous glucose. Thus, cultured human beta-cells can survive for more than 1 year in IDDM patients on maintenance anti-rejection therapy for a prior kidney graft and without the need for an increased immunosuppression at the time of implantation. The use of functionally standardized beta-cell grafts helps to identify recipient and graft factors which influence their survival and metabolic effects. Insulin-independence can be achieved by injection of 1.5 million beta-cells per kg body weight in a liver segment. These beta-cell implants respond well to adenylcyclase activators but poorly to glucose. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glucagon; Glutamate Decarboxylase; Glycated Hemoglobin; Histocompatibility Testing; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Liver; Male; Middle Aged; Tissue Donors; Transplantation, Heterotopic | 1998 |
Biological activity of C-peptide on the skin microcirculation in patients with insulin-dependent diabetes mellitus.
19 insulin-dependent diabetes mellitus (IDDM) patients participated in a randomized double-blind crossover investigation to investigate the impact of human C-peptide on skin microvascular blood flow. The investigation was also carried out with 10 healthy volunteers. Blood pressure, heart rate, blood sugar, and C-peptide levels were monitored during a 60-min intravenous infusion period of C-peptide (8 pmol kg-1 min-1) or saline solution (154 mmol liter-1 NaCl), and 30 min after stopping the infusion. During the same time period, capillary blood cell velocity (CBV), laser Doppler flux (LDF), and skin temperature were assessed in the feet. In the verum arm, C-peptide levels increased after starting infusion to reach a maximum of 2.3+/-0.2 nmol liter-1 after 45 min, but remained below 0. 15 nmol liter-1 during the saline treatment. Baseline CBV was lower in diabetic patients compared with healthy subjects (147+/-3.6 vs. 162+/-4.2 micron s-1; P < 0.01). During C-peptide administration, CBV in IDDM patients increased progressively from 147+/-3.6 to 167+/-3.7 micron s-1; P < 0.001), whereas no significant change occurred during saline infusion or in healthy subjects. In contrast to the CBV measurements, the investigation of LDF, skin temperature, blood pressure, heart rate, or blood sugar did not demonstrate any significant change during the study. Replacement of human C-peptide in IDDM patients leads to a redistribution in skin microvascular blood flow levels comparable to levels in healthy subjects by increasing the nutritive CBV relative to subpapillary arteriovenous shunt flow. Topics: Adult; Blood Flow Velocity; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Female; Foot; Heart Rate; Humans; Infusions, Intravenous; Insulin; Male; Microcirculation; Middle Aged; Regional Blood Flow; Skin; Skin Temperature | 1998 |
Metabolic control in children with insulin-dependent diabetes mellitus 5 y after diagnosis. Early detection of patients at risk for poor metabolic control.
Children (n = 38) aged 3-15 y were randomly chosen, at the time of diabetes diagnosis, for conventional management at a hospital ward, or for treatment partly in a training apartment where the family was offered problem-based education and special therapeutic support. HbA1c, blood glucose stability, urinary C-peptide excretions and incidence of hypoglycaemic attacks and diabetes ketoacidosis (DKA) were monitored and some standardized, self-estimated psychological tests were performed during the first 2 y after diagnosis. During the 3 y thereafter, HbA1c, presence of DKA, microalbuminuria, retinopathy and hypertension were monitored. None of the patients demonstrated signs of diabetes microangiopathy or DKA. The overall mean HbA1c level was 7.2% 5 y after diagnosis and 30% of the children had HbA1c values <6.3%. There were no differences in the HbA1c values for the patients treated by the different management regimens. Blood glucose variability (SD) was also similar, with 75% of the values in the range of 3-10 mmol/l. Patients with poor glycaemic control (mean HbA1c >8.3%) year 5 after diagnosis had already the second year after diagnosis significantly higher HbA1c values and blood glucose variability. The fathers of these patients demonstrated a higher degree of maladjustment. On the basis of increasing HbA1c values, high blood glucose variability and psychosocial risk factors such as their fathers' emotional responses, patients at risk for poor metabolic control in the future can be identified within 2 y after diagnosis. Efforts and resources can thus be focused at an early stage on this group. Topics: Adaptation, Psychological; Adolescent; Albuminuria; Analysis of Variance; Attitude to Health; Blood Glucose; C-Peptide; Chi-Square Distribution; Child; Child, Preschool; Chromatography, High Pressure Liquid; Diabetes Mellitus, Type 1; Family Therapy; Fathers; Female; Glycated Hemoglobin; Humans; Insulin; Male; Patient Education as Topic; Radioimmunoassay; Risk Factors; Statistics, Nonparametric; Sweden | 1998 |
Low dose linomide in Type I juvenile diabetes of recent onset: a randomised placebo-controlled double blind trial.
The quinoline-3-carboxamide, linomide, protects non-obese diabetic mice from diabetes. The effects of linomide on insulin needs and beta cell function were studied in recent juvenile Type I diabetes in a double-blind trial. Patients with recent onset diabetes were randomly assigned to treatment with a fixed dose of 2.5 mg linomide (42 patients) or placebo (21 patients) for 1 year, in addition to insulin and diet. Glycated haemoglobin was 10-15% lower at 9 months (p = 0.003) and 12 months (p < 0.05) in the linomide group. The insulin dose was 32-40% smaller in the linomide group at 3 (p < 0.03), 6 (p < 0.02), 9 (p < 0.001) and 12 months (p = 0.01). Insulin doses correlated negatively with C peptide values (p = 0.001-0.002). The trend for higher C peptide values in the linomide group did not reach significance. In a post hoc subgroup analysis performed in 40 patients (25 from the linomide group and 15 from the placebo group) who still had detectable residual beta cell function at entry, linomide was associated with 45-59% higher C peptide value at 6 months (p < 0.05), 9 months (p < 0.05) and 12 months (p < 0.05). The main adverse effects of linomide were mild transitory anaemia (45 vs 10% in the linomide and placebo groups), thrombocytopenia (24 vs 10%), and mild joint discomfort (45 vs 5%) with no clinical signs. In conclusion, low-dose linomide reduced the insulin needs in patients with juvenile Type I diabetes of recent onset and improved beta cell function in patients who still had detectable beta cell function at entry. These results support further clinical and experimental studies to define the effects of linomide in Type I diabetes provided the safety of linomide is reliably established. Topics: Adjuvants, Immunologic; Adolescent; Adult; Antineoplastic Agents; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hydroxyquinolines; Hypoglycemic Agents; Insulin; Islets of Langerhans; Male | 1998 |
Effect of bacille Calmette-Guérin vaccination on C-peptide secretion in children newly diagnosed with IDDM.
To determine whether administration of bacille Calmette-Guérin (BCG) vaccination to newly diagnosed IDDM patients can help preserve C-peptide secretion over the subsequent 18 months.. Twenty-six IDDM patients, all of whom had been diagnosed within the previous year, had basal C-peptide levels >0.06 nmol/l, and had negative reactions to Mantoux's test, were randomized pairwise as they presented and were given either 0.1 ml (100 microg) BCG vaccine or 0.1 ml saline intradermally Both the patients and the investigators were blinded to the treatment. Fasting and glucagon-induced C-peptide levels and HbA1c were measured in all patients at enrollment and at 1, 3, 6, 9, 12, and 18 months after vaccination, and insulin dose was recorded at each visit.. At enrollment, there was no significant difference in age, duration of diabetes, insulin dose, HbA1c, or fasting C-peptide levels between the BCG-vaccinated and control groups. The mean basal and stimulated C-peptide levels in the BCG-treated group did not differ significantly from those in the control group at any time during the 18 months of follow-up, and there was no difference in insulin dose or HbA1c at any time between the groups.. BCG vaccination in children who have been recently diagnosed with IDDM does not affect the progressive decline in C-peptide levels or alter the clinical course of the disease. Topics: Adolescent; BCG Vaccine; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Fasting; Female; Follow-Up Studies; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Male; Time Factors | 1998 |
Optimal provision of daytime NPH insulin in patients using the insulin analog lispro.
Insulin lispro improves early postprandial blood glucose control but can result in late interprandial hyperglycemia. As an approach to resolving this problem, we performed a randomized, crossover study with four treatment arms, comparing the daytime metabolic profile after either premeal lispro alone or premeal lispro with optimal daytime NPH insulin and with standard human regular insulin.. Twelve C-peptide negative type 1 diabetic patients were studied on four separate study days, at least 7 days apart. On each study day, patients received one of the four study insulin treatments, in random order, with identical meals and snacks. The four treatments were 1) premeal human regular insulin before lunch and supper at unchanged dose; 2) premeal lispro (unchanged dose) at lunchtime and dinner; 3) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 6-h interval until dinner; and 4) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 8-h interval until dinner. All patients were using their usual premeal plus basal insulin regimen during the period of the study, with human regular insulin before meals and NPH insulin at bedtime.. Postprandial blood glucose concentrations (1230-1500) were lower after reduced or usual lispro dose compared with human regular insulin (5.5+/-0.2 and 5.6+/-0.2 vs. 8.2+/-0.5 mmol/l, P < 0.001), with no difference between the lispro doses. However, prepran-Dial (1800) blood glucose levels deteriorated to higher levels after usual-dose lispro alone compared with either human regular insulin (P < 0.05) or reduced-dose lispro plus NPH (P < 0.05) (8.9+/-0.3 vs. 7.1+/-0.8 and 6.4+/-0.4 mmol/l), with no difference between human regular insulin and reduced-dose lispro plus NPH. During the 2 h between the usual and delayed mealtime, blood glucose concentrations remained controlled on lispro plus NPH (2000: 6.5+/-0.4 mmol/l).. Reduced-dose lunchtime lispro plus NPH maintained the improvement in postprandial blood glucose control with no deterioration in interprandial blood glucose control, even up to a late meal. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Cross-Over Studies; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Lispro; Insulin, Isophane; Male; Postprandial Period | 1998 |
Circulating proinsulin levels in insulin-dependent diabetic patients after whole pancreas-kidney transplantation.
Disproportional hyperproinsulinemia is a sensitive marker for beta-cell dysfunction. The objective of this study was to assess the proinsulin profile in persons with insulin-dependent diabetes mellitus (IDDM) after pancreas-kidney transplantation. We determined serum insulin, C-peptide, and proinsulin concentrations during an oral glucose challenge in five pancreas-kidney transplant recipients, nine nondiabetic kidney transplant recipients, and 17 normal subjects. Basal proinsulin concentrations were significantly increased in pancreas-kidney recipients (geometric mean [+/-1 SE range], 6.0 [5.5 to 6.4] pmol/L) and kidney recipients (6.4 [5.4 to 7.5] pmol/L) compared with the normal subjects (2.8 [2.5 to 3.2] pmol/L). Integrated proinsulin concentrations during the oral glucose load were also higher in pancreas-kidney recipients (1.4 [1.1 to 1.8] nmol/L x min) and kidney recipients (1.5 [1.2 to 2.0] nmol/L x min) versus normal subjects (0.8 [0.7 to 0.9] nmol/L x min). There was no difference in basal or integrated proinsulin concentrations between the two transplant groups. Even after adjustment for the glomerular filtration rate (GFR), basal and incremental proinsulin concentrations continued to be higher in the transplant groups than in the normal subjects. Proinsulin to C-peptide molar ratios both before and after the glucose load were similar in the three groups. From these findings, we conclude that pancreas-kidney transplantation provokes proportional hyperproinsulinemia, which is closely associated with its reduced clearance in the kidneys. Topics: Adult; Blood Glucose; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Glomerular Filtration Rate; Humans; Kidney Transplantation; Male; Pancreas Transplantation; Proinsulin | 1998 |
Ketosis resistance in fibrocalculous pancreatic diabetes: II. Hepatic ketogenesis after oral medium-chain triglycerides.
A majority of patients with fibrocalculous pancreatic diabetes (FCPD) do not become ketotic even in adverse conditions. It is not clear whether this ketosis resistance is due to reduced fatty acid release from adipose tissue or to impaired hepatic ketogenesis. We tested hepatic ketogenesis in FCPD patients using a ketogenic challenge of oral medium-chain triglycerides (MCTs) and compared it with that in matched insulin-dependent diabetes mellitus (IDDM) patients and healthy controls. After oral MCTs, FCPD patients showed only a mild increase in blood 3-hydroxybutyrate (3-HB) concentrations (median: fasting, 0.13 mmol/L; peak, 0.52) compared with IDDM patients (fasting, 0.44; peak, 3.39) and controls (fasting, 0.04; peak, 0.75). Plasma nonesterified fatty acid (NEFA) concentrations were comparable in the two diabetic groups (FCPD: fasting, 0.50 mmol/L; peak, 0.79; IDDM: fasting, 0.91; peak, 1.04). Plasma C-peptide concentrations were low and comparable in the two diabetic groups. Plasma glucagon concentrations were higher in IDDM patients in the fasting state, but declined to levels comparable to those in FCPD patients after oral MCTs. Plasma carnitine concentrations were comparable in the two groups of patients. It is concluded that the failure to stimulate ketogenesis under these conditions could be partly due to inhibition of a step beyond fatty acid entry into the mitochondria. Topics: Adipose Tissue; Administration, Oral; Adult; Blood Glucose; C-Peptide; Carnitine; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Fatty Acids; Fatty Acids, Nonesterified; Female; Glucagon; Glycerol; Humans; Hydroxybutyrates; Ketones; Liver; Male; Triglycerides | 1997 |
Subcutaneous glucagon-like peptide I combined with insulin normalizes postcibal glycemic excursions in IDDM.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Male; Middle Aged; Pancreatic Polypeptide; Peptide Fragments; Time Factors | 1997 |
Effects of pramlintide, an analog of human amylin, on plasma glucose profiles in patients with IDDM: results of a multicenter trial.
The effects of subcutaneous administration of 10, 30, or 100 microg q.i.d. pramlintide, an analog of human amylin, on plasma glucose regulation in patients with IDDM were evaluated in a multicenter trial. The plasma glucose response to a Sustacal test meal was significantly reduced compared with placebo both after 1 week and after 2 weeks of administration of 30 or 100 microg pramlintide. In addition, 24-h mean plasma glucose concentrations were significantly lowered in patients receiving 30 microg of pramlintide for 2 weeks compared with placebo, while the 100-microg pramlintide dose did not reach statistical significance for the 24-h glucose profiles. At 10 microg, pramlintide had no effect on the 24-h glucose profile or on the plasma glucose response to a Sustacal test meal. The reduction in 24-h glucose concentrations and glucose concentrations after the Sustacal test meal observed at the 30-microg pramlintide dose was not accompanied by an increased incidence of hypoglycemic events. The most frequent adverse events were dose-related and involved transient upper gastrointestinal symptoms. A majority (>80%) of the patients who reported these adverse events during week 1 did not report them in week 2. These data indicate that pramlintide effectively reduces plasma glucose concentrations as reflected in both a 24-h glucose profile and a Sustacal test meal while maintaining an acceptable safety profile. Topics: Adult; Amyloid; Area Under Curve; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Islet Amyloid Polypeptide; Male; Middle Aged | 1997 |
BCG vaccine in insulin-dependent diabetes mellitus. IMDIAB Group.
Topics: Adolescent; BCG Vaccine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glycated Hemoglobin; Humans; Injections, Intradermal; Insulin; Niacinamide; Remission Induction | 1997 |
Counterregulatory hormone and symptom responses to hypoglycaemia in diabetic children.
The hormonal responses to, and symptoms of, hypoglycaemia were investigated in 19 diabetic children (mean age 14.2 (SD 1.4) years, mean HbA1c 9.8 (SD 1.2)%) and 16 non-diabetic children (14.4(1.0) years) during a gradual reduction in plasma glucose with the glucose clamp technique. Plasma glucose was reduced from approximately 5.7 to approximately 2.6 mmol l(-1) in the diabetic children and from approximately 5.7 to approximately 2.9 mmol l(-1) in the non-diabetic children over 200 min. The mean glycaemic thresholds for adrenaline, and for autonomic and total symptom score, were similar in the diabetic and non-diabetic groups, and were found at plasma glucose levels between 3.4 and 3.7 mmol l(-1). The mean glucose levels which elicited increase of cortisol, growth hormone, and glucagon were lower (p < 0.01), and the mean incremental responses of adrenaline, cortisol, and glucagon were smaller in the diabetic than in the non-diabetic children. In the diabetic children, a correlation was found between Body Mass Index (BMI) and the hypoglycaemic thresholds for autonomic and total symptom scores (r = 0.64, p < 0.01 and r = 0.72, p = 0.001, respectively). We conclude that counterregulatory hormone responses are attenuated in diabetic as compared to non-diabetic children, whereas recognition of autonomic symptoms is similar in the two groups. Diabetic children with a higher BMI seem to have increased awareness of a declining plasma glucose level. Topics: Adolescent; Blood Glucose; Body Mass Index; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Glucose; Glucose Clamp Technique; Glycated Hemoglobin; Growth Hormone; Hormones; Humans; Hydrocortisone; Hypoglycemia; Insulin; Male; Norepinephrine; Time Factors | 1997 |
Effects of C-peptide on insulin-induced hypoglycaemia and its counterregulatory responses in IDDM patients.
Recent studies indicate that C-peptide, when given to patients with insulin-dependent (Type 1) diabetes mellitus (IDDM), exerts significant effects on microvascular and neuronal functions. Adjuvant therapy with C-peptide has been advocated in the treatment of IDDM patients. Since endogenous insulin secretion is believed to be of importance for the alpha-cell function, we addressed the issue whether C-peptide given acutely interferes with the responses to hypoglycaemia. Seven IDDM patients were randomly exposed to hypoglycaemia with and without exogenous C-peptide. Insulin and and C-peptide were given intravenously in equimolar amounts for 3 hours. The decrease of blood glucose was faster and more pronounced during C-peptide infusion, yielding a significantly lower AUC 0-180 min of blood glucose (38.5 +/- 1.6 vs 44.4 +/- 2.2 mmol l(-1)h(-1); p = 0.032). No difference between the two experiments was found concerning glucagon when the AUC, delta-values or levels at separate points of time were calculated. In conclusion, the main finding of this study was that exogenous C-peptide, given acutely, gave rise to a more rapid onset of hypoglycaemia yielding no detectable differences with respect to the response of glucagon and other counterregulatory hormones. Topics: Adult; Area Under Curve; Blood Glucose; C-Peptide; Chromatography, High Pressure Liquid; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Humans; Hypoglycemia; Hypoglycemic Agents; Infusions, Intravenous; Insulin; Male; Pilot Projects; Radioimmunoassay | 1997 |
High-dose intravenous insulin infusion versus intensive insulin treatment in newly diagnosed IDDM.
High-dose intravenous insulin infusion at the onset of IDDM has been suggested to improve beta-cell function during the 1st year of insulin treatment. To test this hypothesis, we randomly assigned newly diagnosed IDDM patients to receive either an experimental 2-week high-dose intravenous insulin infusion (n = 9; age, 25 +/- 7 years; HbA1e, 10.5 +/- 2.0%) or an intensive insulin therapy of four injections per day (n = 10; age, 28 +/- 7 years; HbA1c, 12.3 +/- 3.0%). The experimental-therapy group received three times more insulin (1.2 +/- 0.4 U.kg-1.day-1) than the intensive-therapy group (0.4 +/- 0.1 U.kg-1. day-1, P < 0.0005). By week 3, both groups were treated similarly with intensive insulin therapy and were followed for 1 year. beta-cell function was evaluated with fasting plasma C-peptide and glucagon-stimulated and mixed meal-stimulated C-peptide concentrations. In both groups, insulin doses were comparable, and HbA1c levels were near normal during follow-up. At diagnosis of IDDM, fasting C-peptide was 0.40 +/- 0.13 nmol/l in the experimental-therapy group and 0.39 +/- 0.23 nmol/l in the intensive-therapy group. Irrespective of treatment, a slight decline of fasting C-peptide was observed in sequential measurements up to 12 months in both groups (delta, -0.13 and -0.08 nmol/l, respectively; NS). Glucagon-stimulated C-peptide concentrations decreased from 0.54 +/- 0.18 and 0.70 +/- 0.39 nmol/l at month 0 to 0.41 +/- 0.20 and 0.61 +/- 0.52 nmol/l, respectively, at month 12. In the experimental-therapy group, mixed meal-stimulated C-peptide concentrations (area under the curve over 2 h) increased from 82.10 +/- 43.72 to 101.20 +/- 32.53 nmol/l and in the intensive-therapy group, from 75.05 +/- 46.01 to 107.20 +/- 102.51 nmol/l. Changes in stimulated C-peptide concentrations between month 0 and 12 were not significant in both groups. During follow-up, fasting and stimulated C-peptide concentrations were not significantly different between the experimental-therapy group and the intensive-therapy group. We conclude that as initial treatments of newly diagnosed IDDM, high-dose intravenous insulin infusion and intensive insulin therapy equally preserve beta-cell function during the 1st year of insulin therapy. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Food; Glucagon; Glycated Hemoglobin; Humans; Infusions, Intravenous; Insulin; Islets of Langerhans; Male | 1997 |
Vitamin E and nicotinamide have similar effects in maintaining residual beta cell function in recent onset insulin-dependent diabetes (the IMDIAB IV study)
Protection of residual beta cell function at the time of diagnosis of insulin-dependent diabetes mellitus (IDDM) by intensive insulin therapy and the addition of nicotinamide (NA) has been established. The objective of this study was to evaluate the effect of a free oxygen radical scavenger such as vitamin E (Vit E) on residual beta cell function and parameters of metabolic control in patients with recent onset IDDM undergoing intensive insulin therapy.. The effect of Vit E was compared with that of NA (control group) in a randomized multicentre trial.. Eighty-four IDDM patients between 5 and 35 years of age (mean age 15.8 +/- 8.4 (s.d.) years) entered a one year prospective study. One group of patients (n = 42) was treated with Vit E (15 mg/kg body weight/day) for one year; the other group (n = 42) received NA for one year (25 mg/kg body weight/day). All patients were under intensive insulin therapy with three to four injections a day. Basal and stimulated (1 mg i.v. glucagon) C-peptide secretion, glycosylated haemoglobin and insulin dose were evaluated at diagnosis and at three-monthly intervals up to one year.. Preservation and slight increase of C-peptide levels at one year compared with diagnosis were obtained in the two treated patient groups. No statistically significant differences were observed in basal or stimulated C-peptide levels between the two groups of patients for up to one year after diagnosis. Glycosylated haemoglobin and insulin dose were also similar between the two groups; however patients receiving Vit E under the age of 15 years required significantly more insulin than NA-treated patients one year after diagnosis (P < 0.04).. Our data indicate that Vit E and NA possess similar effects in protecting residual beta cell function in patients with recent onset IDDM. Since their putative mechanism of protection on beta cell cytotoxicity is different, combination of these two vitamins may be envisaged for future trials of intervention at IDDM onset. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Leukopenia; Niacinamide; Prospective Studies; Vitamin E | 1997 |
Diagnostic significance of antibodies to glutamic acid decarboxylase in Japanese diabetic patients with secondary oral hypoglycemic agents failure.
Some non-insulin-dependent diabetes mellitus (NIDDM) patients are positive for antibodies to glutamic acid decarboxylase (anti-GAD), and they tend to develop insulin deficiency. The aim of this study was to evaluate the prevalence of anti-GAD in NIDDM with secondary failure of sulfonylurea agents (NIDDM-SF) and to investigate the diagnostic significance of seropositivity for anti-GAD in NIDDM-SF patients by evaluating human leukocyte antigen (HLA)-DRB1 alleles concurrently. The prevalence of anti-GAD in NIDDM-SF, NIDDM, and new-onset (within 1 year after onset) insulin-dependent diabetes mellitus (IDDM) was 9.3% (39/420), 3.1% (12/392), and 65.0% (13/20), respectively. Pancreatic beta cell function deteriorated in NIDDM-SF patients positive for anti-GAD. HLA-DRB1 allele typing revealed that NIDDM-SF patients positive for anti-GAD were significantly associated with DRB1*0901 (RR = 2.81, P < 0.01), which is one of the susceptible alleles to IDDM. Shorter interval before development of secondary failure and insulin deficiency were significantly associated with the presence of DRB1*0901 (P < 0.05) in NIDDM-SF patients positive for anti-GAD. In conclusion, nearly 10% of NIDDM-SF patients are positive for anti-GAD, suggesting that an autoimmune mechanism might play an important role in the pathogenesis of NIDDM-SF patients. In addition, a combination of serological marker (anti-GAD) and genetic marker (HLA-DRB1) is useful for predicting clinical course of NIDDM patients with secondary failure of sulfonylurea agents. Topics: Adolescent; Adult; Aged; Alleles; Antibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Hypoglycemic Agents; Male; Middle Aged; Sulfonylurea Compounds; Treatment Failure | 1997 |
Effects of octreotide on glycaemic control, glucose disposal, hepatic glucose production and counterregulatory hormones secretion in type 1 and type 2 insulin treated diabetic patients.
We studied the effects of continuous subcutaneous infusion of octreotide (100 micrograms/day for 5 days) on glycaemic values, counterregulatory hormones secretion, hepatic glucose production (HGP) and glucose disposal during an euglycaemic clamp in 7 C-peptide-negative type 1 diabetic patients and 7 C-peptide positive insulin-treated type 2 diabetic patients. In type 1, but not type 2 diabetic patients, octreotide significantly reduced glycaemic values (P < 0.005) and also diminished HGP during an euglycaemic clamp (P < 0.05). However, insulin stimulated global glucose uptake remained unchanged. GH, glucagon, IGF-I, IGFBP-3 levels, were significantly lowered by octreotide in both type 1 and type 2 diabetic patients whereas cortisol and epinephrine remained unmodified. Moreover in type 2 diabetic patients both basal (P < 0.05) and after-meal (P < 0.01) C-peptide secretion was reduced by octreotide. These data point to different metabolic effects of octreotide in type 1 versus type 2 diabetic patients with the drug only being able to reduce glycaemic values and HGP in the former but not in the latter subjects. The failure of octreotide to diminish glycaemic values and HGP in type 2 diabetic patients in spite of its ability to lower GH and glucagon may probably depend on temporary blockage of residual endogenous insulin secretion induced by octreotide administration. Topics: Adult; Antineoplastic Agents, Hormonal; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose; Hormones; Humans; Hyperglycemia; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Liver; Male; Middle Aged; Octreotide | 1997 |
Long-term results of early cyclosporin therapy in juvenile IDDM.
In juvenile IDDM patients, immunosuppression with cyclosporin A allows partial beta-cell function recovery and transient remissions of insulin dependency. The effects of this therapeutic approach, however, have not been evaluated in the long-term, since no reported trial exceeded 1 year. Here we analyze 130 diabetic children followed at our institution during the first years of their disease. Cyclosporin was given to 83 of them at an initial dose of 7.2 +/- 0.1 mg.kg-1.day-1, which was decreased stepwise then interrupted after 6-62 months, depending on the response to therapy. A total of 47 diabetic children, who served as control subjects in two trials, were pooled for comparison. Over 4 years, the cyclosporin-treated group kept plasma C-peptide approximately twice as high as the control group (P < 0.02). It took 5.8 +/- 0.6 years for C-peptide secretion stimulated by glucagon to become undetectable in the cyclosporin group versus 3.2 +/- 0.6 years in the control group (P < 0.02). Average insulin dose remained lower by 0.2-0.4 U.kg-1.day-1 and glycated hemoglobin by approximately 1% in cyclosporin-treated patients (P < 0.02), who also had less hypoglycemia than the diabetic control subjects (P < 0.05). After 4 years, differences between the groups became nonsignificant. We observed no significant secondary effects of cyclosporin. In conclusion, positive effects of low-dose cyclosporin in recently diagnosed clinical IDDM patients are prolonged beyond interruption of the drug. The magnitude and duration of the benefit, however, do not appear sufficient to justify this immunosuppressive treatment in clinical practice. Topics: Autoantibodies; C-Peptide; Child; Cyclosporine; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Follow-Up Studies; Glycated Hemoglobin; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans; Longitudinal Studies; Prognosis | 1996 |
Glucagonostatic actions and reduction of fasting hyperglycemia by exogenous glucagon-like peptide I(7-36) amide in type I diabetic patients.
Glucagon-like peptide I(7-36) amide (GLP-1) is a physiological incretin hormone that, in slightly supraphysiological doses, stimulates insulin secretion, lowers glucagon concentrations, and thereby normalizes elevated fasting plasma glucose concentrations in type II diabetic patients. It is not known whether GLP-1 has effects also in fasting type I diabetic patients.. In 11 type I diabetic patients (HbA1c 9.1 +/- 2.1%; normal, 4.2-6.3%), fasting hyperglycemia was provoked by halving their usual evening NPH insulin dose. In random order on two occasions, 1.2 pmol . kg-1 . min-1 GLP-1 or placebo was infused intravenously in the morning (plasma glucose 13.7 +/- 0.9 mmol/l; plasma insulin 26 +/- 4 pmol/l). Glucose (glucose oxidase method), insulin, C-peptide, glucagon, GLP-1, cortisol, growth hormone (immunoassays), triglycerides, cholesterol, and nonesterified fatty acids (enzymatic tests) were measured.. Glucagon was reduced from approximately 8 to 4 pmol/l, and plasma glucose was lowered from 13.4 +/- 1.0 to 10.0 +/- 1.2 mmol/l with GLP-1 administration (plasma concentrations approximately 100 pmol, P < 0.0001), but not with placebo (14.2 +/- 0.7 to 13.2 +/- 1.0). Transiently, C-peptide was stimulated from basal 0.09 +/- 0.02 to 0.19 +/- 0.06 nmol/l by GLP-1 (P < 0.0001), but not by placebo (0.07 +/- 0.02 to 0.07 +/- 0.02). There was no significant effect on nonesterified fatty acids (P = 0.34), triglycerides (P = 0.57), cholesterol (P = 0.64), cortisol (P = 0.40), or growth hormone (P = 0.53).. Therefore, exogenous GLP-1 is able to lower fasting glycemia also in type I diabetic patients, mainly by reducing glucagon concentrations. However, this alone is not sufficient to normalize fasting plasma glucose concentrations, as was previously observed in type II diabetic patients, in whom insulin secretion (C-peptide response) was stimulated 20-fold. Topics: Adult; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Fatty Acids, Nonesterified; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Humans; Insulin; Male; Peptide Fragments; Protein Precursors; Time Factors | 1996 |
C-peptide improves autonomic nerve function in IDDM patients.
In order to determine the possible influence of C-peptide on nerve function, 12 insulin-dependent diabetic (IDDM) patients with symptoms of diabetic polyneuropathy were studied twice under euglycaemic conditions. Tests of autonomic nerve function (respiratory heart rate variability, acceleration and brake index during tilting), quantitative sensory threshold determinations, nerve conduction studies and clinical neurological examination were carried out before and during a 3-h i.v. infusion of either C-peptide (6 pmol.kg-1.min-1) or physiological saline solution in a double-blind study. Plasma C-peptide concentrations increased from 0.11 +/- 0.02 to 1.73 +/- 0.04 nmol/l during C-peptide infusion. Clinical neurological examination quantitative sensory threshold evaluations and nerve conduction measurements failed to detect significant changes between C-peptide and saline study periods. Respiratory heart rate variability increased significantly from 13 +/- 1 to 20 +/- 2% during C-peptide infusion (p < 0.001), reaching normal values in five of the subjects; control studies with saline infusion did not alter the heart rate variability (basal, 14 +/- 2; saline, 15 +/- 2%). A reduced brake index value was found in seven patients and increased significantly during the C-peptide infusion period (4.6 +/- 1.0 to 10.3 +/- 2.2%, p < 0.05) but not during saline infusion (5.9 +/- 2 to 4.1 +/- 1.1%, NS). It is concluded that short-term (3-h) infusion of C-peptide in physiological amounts may improve autonomic nerve function in patients with IDDM. Topics: Adult; Autonomic Pathways; Blood Glucose; Blood Pressure; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Heart Rate; Hot Temperature; Humans; Insulin; Male; Middle Aged; Pain; Smoking; Temperature; Vibration | 1996 |
Diazoxide treatment at onset preserves residual insulin secretion in adults with autoimmune diabetes.
Twenty islet cell antibody (ICA)-positive patients, aged 19-38 years, with IDDM were randomized at onset to treatment with either diazoxide, a K+ channel opener that inhibits the release of insulin, or placebo for 3 months, in addition to multiple insulin injection therapy. The patients who were given diazoxide displayed higher residual insulin secretion than the placebo group after 1 year (basal C-peptide level, 0.40 +/- 0.04 vs. 0.25 +/- 0.04 [mean +/- SE] nmol/l; P < 0.021) and at an 18-month follow-up (0.37 +/- 0.06 vs. 0.20 +/- 0.01 nmol/l, P < 0.033). Metabolic control did not differ between the two groups. During the course of the study, no differences in islet cell or GAD autoantibodies were detected between the two groups. The results of this study warrant further trials to explore the potential of inducing target cell rest in order to halt the loss of insulin-producing cells during the early course of the disease. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diazoxide; Drug Therapy, Combination; Female; Follow-Up Studies; Glucagon; Glutamate Decarboxylase; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Placebos; Time Factors | 1996 |
Glycemic effect of a single high oral dose of the novel sweetener sucralose in patients with diabetes.
To examine the effect of a single high oral dose of the novel noncaloric sweetener sucralose on short-term glucose homeostasis in patients with IDDM or NIDDM.. A total of 13 IDDM and 13 NIDDM patients with glycosylated hemoglobin levels < 10% completed this double-blind cross-over study. After an overnight fast, patients were administered opaque capsules containing either 1,000 mg sucralose or cellulose placebo, followed by a standardized 360-kcal liquid breakfast. Plasma glucose and serum C-peptide levels were measured over the next 4 h.. Regardless of the type of diabetes, areas under the curves for changes of plasma glucose and serum C-peptide levels after sucralose administration were not significantly different from those after placebo. During test meals with sucralose, one episode of symptomatic hypoglycemia occurred in each of three IDDM patients, but these episodes were not considered the result of sucralose administration.. The present results support the conclusion that sucralose consumption does not adversely affect short-term blood glucose control in patients with diabetes. Topics: Administration, Oral; Adult; Blood Glucose; C-Peptide; Cross-Over Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Double-Blind Method; Fasting; Female; Glycated Hemoglobin; Homeostasis; Humans; Male; Middle Aged; Sucrose; Sweetening Agents | 1996 |
Hyper insulinism and decreased insulin sensitivity in nonobese healthy offspring of conjugal diabetic parents and individuals with IGT and NIDDM.
Insulin sensitivity was measured by insulin tolerance test using KITT as an index of insulin mediated glucose metabolism in 9 non-obese healthy offspring of conjugal diabetic parents (OCDP) and 9 non-obese NIDDM patients. The mean KITT value in the offspring of conjugal diabetic parents was 3.85 +/- 1.64 min-1 x 100 which was lower (P < 0.05) than the value of 5.49 +/- 1.9 min-1 x 100 in the control subjects. While, the mean KITT value in NIDDM patients was 1.85 +/- 0.9 min-1 x 100 which was significantly lower (P < 0.001) than that in the control subjects. Estimation of plasma immunoreactive insulin (IRI) and C-peptide in these subjects and in subjects with impaired glucose tolerance (IGT) showed significantly higher levels of insulin than that in the control subjects but there was no corresponding increase in the C-peptide levels. The mean area under the insulin curve (IRI) was 242 +/- 69 microU/ml in the control subjects versus 527 +/- 206 microU/ml in IGT (P < 0.001), 648 +/- 215 microU/ml in NIDDM (P < 0.001) and 466 +/- 130 microU/ml in OCDP (P < 0.001). These results suggest that 1) healthy offspring of two type II diabetic parents have decreased insulin sensitivity and insulin resistance is present in all the NIDDM patients, 2) peripheral hyperinsulinism is a common feature in healthy offspring of conjugal diabetic parents, and in subjects with IGT and mild NIDDM and this hyperinsulinism is not due to increased B-Cell secretion but due to some metabolic alterations of insulin occurring at the extra pancreatic levels. Topics: Adult; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Intolerance; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Male | 1996 |
Double blind trial of nicotinamide in recent-onset IDDM (the IMDIAB III study).
Nicotinamide has been recently introduced, in addition to intensive insulin therapy for patients with recent-onset insulin-dependent diabetes mellitus (IDDM) to protect beta cells from end-stage destruction. However, available data are conflicting. A double blind trial in 56 newly-diagnosed IDDM patients receiving nicotinamide for 12 months at a dose of 25 mg/kg body weight or placebo was designed in order to determine whether this treatment could improve the integrated parameters of metabolic control (insulin dose, glycated haemoglobin and C-peptide secretion) in the year after diagnosis. In addition to nicotinamide or placebo, patients received three to four insulin injections daily to optimize blood glucose levels. Patients treated with nicotinamide or placebo received similar doses of insulin during follow-up and 1 year after diagnosis with comparable glycated haemoglobin levels 6.7 +/- 1.8% nicotinamide vs 7.1 +/- 0.6% placebo). Basal and glucagon stimulated C-peptide secretion detectable at diagnosis were similarly preserved in the course of 12 months follow-up both in nicotinamide and placebo treated patients. No adverse effects were observed in patients receiving nicotinamide. When age at diagnosis was taken into account, nicotinamide treated older patients ( > 15 years of age) showed significantly higher stimulated C-peptide secretion than placebo treated patients (p < 0.02). These results suggest that nicotinamide can preserve and improve stimulated beta-cell function only in patients diagnosed after puberty.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Age Factors; Analysis of Variance; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Male; Niacinamide; Placebos; Time Factors | 1995 |
Influence of residual C-peptide secretion on the arginine vasopressin response to hypoglycaemia and metoclopramide in insulin-dependent diabetes.
Arginine vasopressin (AVP) hypersecretion in response to metoclopramide or to insulin-induced hypoglycaemia has been described in type I diabetes mellitus. In the present study, we examined whether residual endogenous insulin secretion may play a role in the control of this abnormal AVP secretory pattern. For this purpose, 21 insulin-dependent diabetic men and 10 age- and weight-matched normal men were tested with MCP (20 mg in an i.v. bolus). On a different occasion, subjects were tested with insulin (0.15 IU kg-1). The diabetic patients were subdivided into C-peptide negative patients (CpN, 11 patients without detectable endogenous pancreatic beta cell activity) (group I) and C-peptide positive patients (CpP, 10 patients with residual endogenous insulin secretion) (group II). Experiments started after optimization of the metabolic status of the diabetic men by 3 days of treatment with continuous subcutaneous insulin infusion. The basal concentrations of AVP were similar in all groups. The administration of MCP induced a striking elevation in plasma AVP levels in the normal controls and in the diabetic subjects of groups I and II. However, the AVP rise was significantly higher in group I and group II than in normal controls. Furthermore, group I diabetics showed higher AVP increments than group II. Insulin induced a similar hypoglycaemic nadir in all subjects at 30 min, even though the diabetic subjects of groups I and II had a delayed recovery in blood glucose levels. The hypoglycaemic pattern was similar in group I and II. Hypoglycaemia induced a striking AVP increase in the normal controls.(ABSTRACT TRUNCATED AT 400 WORDS) Topics: Adult; Antiemetics; Arginine Vasopressin; C-Peptide; Diabetes Mellitus, Type 1; Humans; Hypoglycemia; Insulin; Male; Metoclopramide | 1995 |
Protein content of the evening meal and nocturnal plasma glucose regulation in type-I diabetic subjects.
The effect of two isocaloric evening meals (low protein-high fat vs. high protein-low fat content) on plasma glucose regulation during the night were compared. Eight C-peptide-deficient type-I diabetic subjects without autonomic neuropathy were treated with fixed doses of continuous infusions of insulin during 2 nights. At 7 p.m. they received in random order either a low protein-high fat (5% of total energy protein, 60% fat, 35% carbohydrate) or a high protein-low fat (35% protein, 30% fat, 35% carbohydrate) evening meal. Venous plasma samples were drawn hourly thereafter. Plasma glucose concentrations were similar postprandially during the 2 nights between 7 p.m. and 11 p.m., but they were higher in the early morning hours after the high protein meal (p < 0.02 vs. the low protein meal). Two subjects developed symptomatic hypoglycemia after the low protein meal. Plasma glucagon concentrations were higher (p = 0.023) and serum free insulin lower (p < 0.05) after the high protein-low fat meal. Plasma cortisol and growth hormone were not significantly different between the two diets. Therefore, an increase in the protein content of the evening meal (fat content diminished) increases plasma glucose concentrations several hours later in the night, possibly due to protein-induced glucagon secretion and to lower plasma free insulin levels. Patients with type-I diabetes with a tendency to develop hypoglycemia during the night may avoid this problem by increasing the protein content of the evening meal. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dietary Fats; Dietary Proteins; Fatty Acids, Nonesterified; Glucagon; Growth Hormone; Humans; Hydrocortisone; Middle Aged | 1995 |
Serum insulin profiles in consecutive children 2 years after the diagnosis of IDDM.
We studied associations of 24-h serum insulin profiles with insulin dose, age, gender, haemoglobin A1c (HbA1c) and C-peptide values, as well as blood glucose profiles in 77 consecutive children-nine aged 2-4, 14 aged 5-8, 26 aged 9-12, and 28 aged 13-17 years--2 years after the onset of insulin-dependent diabetes mellitus (IDDM). Mean weight-based insulin doses in the four age groups were similar (0.7 +/- 0.2 U.kg-1.day-1 in all); body surface-area-based doses differed. Insulin doses correlated significantly with the 24-h mean and area-under-the-curve (AUC) values, and with mean values at 03.00 hours of serum insulin in the children aged 5-8 and 13-17 years. The mean insulin concentrations of the age groups (95% confidence intervals) increased with age [6.1 (3.8, 9.7), 7.6 (5.9, 9.8), 10.4 (8.6, 12.4), and 14.0 (11.6, 16.8) mU/l; p < 0.0002]. The 24-h mean of serum insulin together with HbA1c concentration predicted 32% of the variation of mean blood glucose concentrations. Of children aged less than 9 years, 50% had insulin values less than 5 mU/l (healthy subjects' lower reference limit), and 14% were of less than 2 mU/l (detection limit of the assay) at 03.00 hours. At 07.00 hours, 82% had insulin values of less than 5 mU/l, and 36% were of less than 2 mU/l, respectively. Some young children had night-time hypoglycaemia with simultaneous hypoinsulinaemia. Insulin profiles correlated poorly with the HbA1c and peak C-peptide values.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male; Prospective Studies | 1995 |
The effects of non-insulin-dependent diabetes mellitus on the kinetics of onset of insulin action in hepatic and extrahepatic tissues.
The mechanism(s) of insulin resistance in non-insulin-dependent diabetes mellitus remains ill defined. The current studies sought to determine whether non-insulin-dependent diabetes mellitus is associated with (a) a delay in the rate of onset of insulin action, (b) impaired hepatic and extrahepatic kinetic responses to insulin, and (c) an alteration in the contribution of gluconeogenesis to hepatic glucose release. To answer these questions, glucose disappearance, glucose release, and the rate of incorporation of 14CO2 into glucose were measured during 0.5 and 1.0 mU/kg-1 per min-1 insulin infusions while glucose was clamped at approximately 95 mg/dl in diabetic and nondiabetic subjects. The absolute rate of disappearance was lower (P < 0.05) and the rate of increase slower (P < 0.05) in diabetic than nondiabetic subjects during both insulin infusions. In contrast, the rate of suppression of glucose release in response to a change in insulin did not differ in the diabetic and nondiabetic subjects during either the low (slope 30-240 min:0.02 +/- 0.01 vs 0.02 +/- 0.01) or high (0.02 +/- 0.00 vs 0.02 +/- 0.00) insulin infusions. However, the hepatic response to insulin was not entirely normal in the diabetic subjects. Both glucose release and the proportion of systemic glucose being derived from 14CO2 (an index of gluconeogenesis) was inappropriately high for the prevailing insulin concentration in the diabetic subjects. Thus non-insulin-dependent diabetes mellitus slows the rate-limiting step in insulin action in muscle but not liver and alters the relative contribution of gluconeogenesis and glycogenolysis to hepatic glucose release. Topics: Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gluconeogenesis; Glucose; Glucose Clamp Technique; Glycerol; Humans; Infusions, Intravenous; Insulin; Kinetics; Lactates; Liver; Male; Middle Aged; Organ Specificity; Reference Values | 1995 |
Modification of methodology results in improvement in simultaneous kidney-islet success.
Topics: Antilymphocyte Serum; Azathioprine; C-Peptide; Cells, Cultured; Cyclosporine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Immunosuppression Therapy; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Muromonab-CD3; Postoperative Complications; Prednisone; Tissue Preservation; Transplantation, Heterotopic; Transplantation, Homologous | 1995 |
The use of FK506 in simultaneous pancreas/kidney transplantation: rescue, induction, and maintenance immunosuppression.
Topics: Blood Glucose; C-Peptide; Creatinine; Cyclosporine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glycated Hemoglobin; Graft Rejection; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Kidney Transplantation; Pancreas Transplantation; Tacrolimus | 1995 |
Cyclosporin A does not delay insulin dependency in asymptomatic IDDM patients.
To measure the effects of cyclosporin A (CyA) with no insulin therapy on glucose tolerance and beta-cell function in the preclinical phase of insulin-dependent diabetes mellitus (IDDM).. beta-cell responses to the intravenous glucose tolerance test (IVGTT), hyperglycemic clamp, intravenous arginine, and intravenous glucagon were evaluated before and after a 6-month course of CyA in seven patients (mean age 19.6 years) with asymptomatic IDDM.. Initial insulin secretory responses were severely decreased when the patients were compared with eight healthy control subjects: IVGTT (1 + 3 min): 106 +/- 16 vs. 884 +/- 190 pmol/l (P < 0.001); hyperglycemic clamp: 102 +/- 16 vs. 310 +/- 42 pmol/l (P < 0.001); intravenous arginine: 346 +/- 72 vs. 1104 +/- 168 pmol/l (P < 0.01); and intravenous glucagon: 170 +/- 37 vs. 247 +/- 35 pmol/l (NS). The beta-cell responses remained markedly abnormal after 6 months of CyA, although the response to intravenous glucose and oral glucose tolerance tests improved in three subjects. All the patients became insulin-dependent after 5-36 months.. CyA alone is not a suitable treatment for asymptomatic IDDM. Earlier identification of subjects with substantial beta-cell secretory capacity and newer nontoxic intervention strategies are required for the prevention of IDDM. Topics: Adolescent; Adult; Arginine; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glucose Clamp Technique; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Insulin Secretion; Islets of Langerhans; Male; Reference Values | 1995 |
More uniform diurnal blood glucose control and a reduction in daily insulin dosage on addition of glibenclamide to insulin in type 1 diabetes mellitus: role of enhanced insulin sensitivity.
Combination therapy with insulin and sulphonylurea has gained acceptance in management of subjects with Type 2 (non-insulin-dependent) diabetes mellitus. However, its role in management of Type 1 (insulin-dependent) diabetes mellitus remains controversial. In this study, the effect of combination therapy with insulin and glibenclamide on metabolic control, daily insulin dosage, and insulin sensitivity was assessed in subjects with Type 1 diabetes mellitus. Ten men with Type 1 diabetes mellitus participated in a randomized, double-blind, crossover, clinical trial with three treatment regimens, namely (1) insulin alone, (2) insulin and placebo, (3) insulin and glibenclamide, each lasting 3 months. Combination therapy induced: (1) reduction in daily insulin dosage; (2) more uniform blood glucose control as reflected by a lower average 24 h blood glucose level, a smaller difference between mean preprandial and 2 h postprandial blood glucose concentrations, decreased 24 h urine glucose excretion, and a decline in number of hypoglycaemic events; (3) improved insulin sensitivity as expressed by more rapid plasma glucose disappearance rate, without a significant alteration in fasting plasma glucagon and 1h postprandial serum C-peptide levels; when compared with treatment with either insulin alone or with insulin and placebo. Therefore, it is apparent that the addition of glibenclamide to insulin reduces daily insulin dosage and renders a greater uniformity to diurnal blood glucose control, most probably secondary to enhancement of insulin sensitivity. Topics: Adult; Aged; Blood Glucose; Body Weight; C-Peptide; Cholesterol; Circadian Rhythm; Cross-Over Studies; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Glucagon; Glyburide; Glycated Hemoglobin; Glycosuria; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Male; Middle Aged; Placebos; Triglycerides | 1995 |
Does C-peptide have a physiological role?
Short-term administration of physiological amounts of C-peptide to patients with insulin-dependent diabetes was found to reduce the glomerular hyperfiltration in these patients as well as augment whole body glucose utilization. It could also be shown that C-peptide administration increases blood flow, oxygen uptake and capillary diffusion capacity of exercising forearm muscle in IDDM patients, probably by increasing capillary recruitment in the working muscle. Studies under in vitro conditions have shown that C-peptide stimulates glucose transport in skeletal muscle with its maximal effect within the physiological concentration range. The findings in a clinical study in which IDDM patients were given C-peptide and insulin or insulin alone for 4 weeks in a double-blind randomized study design, indicate that C-peptide improves renal function by reducing urinary albumin excretion and glomerular filtration, decreases blood retinal barrier leakage and improves metabolic control. Preliminary findings suggest that C-peptide administration on a short-term basis (3h) may ameliorate autonomic neuropathy by restoring to near normal the heart rate variability in response to expiration and inspiration. Insight into a possible mechanism of action of C-peptide is provided by the finding that C-peptide stimulates Na+K(+)-ATPase activity in renal tubular segments. In conclusion, the present results suggest that, contrary to the prevailing view, C-peptide possesses important physiological effects. Topics: Animals; Awards and Prizes; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Double-Blind Method; Europe; Glucose; History, 20th Century; Humans; Insulin; Kidney; Muscles; Randomized Controlled Trials as Topic; Regional Blood Flow; Societies, Medical; Sweden | 1994 |
[Effects of Tripterygiitotorum in the treatment of insulin dependent diabetes mellitus with islet transplantation].
The therapeutical efficacy of islet transplantation in treating insulin-dependent diabetes mellitus (IDDM) patients is marked for a short time and the long-term efficacy is unsatisfactory. So 30 IDDM patients given tripterygiitotorum (T II) were compared with 24 IDDM patients without using any immunosuppressive agents after islet transplantation.. prior to transplantation both the numbers of T lymphocyte subpopulations such as CD2, CD4, CD8 and the concentrations of C-peptide in all IDDM patients were lowered; after transplantation the numbers of CD2, CD4 were significantly elevated (P < 0.01), the ratio of CD4/CD8 in control group was higher than that in TII group (P < 0.01), while the concentration of C-peptide were greatly increased (normal: 2.24 +/- 0.34; before transplantation: 0.21 +/- 0.01; 15 days after transplantation: 3.24 +/- 1.2 ng/ml). The peak value of C-peptide in TII group began decreasing half a year after transplantation and it gradually dropped to the baseline level. The dose of insulin all were significantly reduced, and 3 patients stopped altogether. Half a year after transplantation TII group remained stable for the requirement of insulin, whereas the control group gradually increased the dose of insulin. (1) Islet transplantation could adjust the immunological disorder in IDDM patients, increase the numbers of T lymphocyte subset such as CD2, CD4, CD8 while the chronic immuno-rejective response occurred. (2) T II inhibited both the numbers and function of T lymphocyte subpopulation and normalized the ratio of CD4/CD8. (3) TII prolonged the survival time of grafts in IDDM patients and suppressed immunological rejection.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; C-Peptide; CD4-CD8 Ratio; Diabetes Mellitus, Type 1; Drugs, Chinese Herbal; Female; Fetal Tissue Transplantation; Humans; Immunosuppressive Agents; Islets of Langerhans Transplantation; Male; Saponins; T-Lymphocyte Subsets; Tripterygium | 1994 |
Hypoglycemia increases muscle sympathetic nerve activity in IDDM and control subjects.
The relationship between the increase in adrenomedullary catecholamine secretion and the sympathetic response to hypoglycemia is not well understood in humans. To explore this relationship more closely, we directly muscle sympathetic nerve activity (MSNA) in control subjects and in insulin-dependent diabetes mellitus (IDDM) subjects without clinically evident diabetic complications.. Twelve IDDM subjects (22.5 +/- 3.9 years of age, diabetes duration of 9.8 +/- 8.3 years) and 12 age-matched control subjects were studied. MSNA was measured during insulin infusion (720 pM.m-2.min-1) with 30-min periods of 1) euglycemia, 2) hypoglycemia (target plasma glucose, 2.8 mM), and 3) recovery. The effect of increased insulin dose (1,440 pM.m-2.min-1) was studied in six subjects in each group, and the effect of prolonged hypoglycemia (1 h) was studied in five IDDM subjects and four control subjects.. MSNA levels increased in IDDM and control subjects, 31 +/- 8 and 29 +/- 6%, respectively, above euglycemia during hypoglycemia and returned to euglycemic levels during recovery. MSNA levels during hypoglycemia were lower in IDDM subjects than in control subjects (26 +/- 3 vs. 35 +/- 2 bursts/min, P < 0.01). Importantly, no relationships were found between the MSNA and epinephrine responses to hypoglycemia in either group. Increasing the insulin infusion rate did not alter the MSNA response to hypoglycemia. During prolonged hypoglycemia, MSNA remained elevated above euglycemic levels throughout hypoglycemia.. These results demonstrate that insulin-induced hypoglycemia increases muscle sympathetic neural outflow in IDDM and control subjects. The lack of correlation between the MSNA and epinephrine responses to hypoglycemia indicates that the adrenomedullary and peripheral sympathetic responses to hypoglycemia are independently mediated. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Clamp Technique; Glycated Hemoglobin; Humans; Hypoglycemia; Muscles; Reference Values; Sympathetic Nervous System; Time Factors | 1994 |
Metabolic control is not altered when using indwelling catheters for insulin injections.
To determine if the use of indwelling catheters for insulin injections affects the long- and short-term metabolic control of insulin-dependent diabetes mellitus (IDDM).. Sixteen children and adolescents 9-20 years of age were included in a randomized 10-week crossover study using indwelling catheters (Insuflon, Pharma-Plast, Lynge, Denmark; CHRONIMED, Minnetonka, Minnesota) for insulin injections. Their diabetes duration was 7.5 +/- 3.3 years (range 2-14), and they used multiple injection therapy with 4-5 doses/day. C-peptide was < or = 0.15 nM fasting and < or = 0.30 nM postprandial.. We found no significant difference between those with and without Insuflon in degree of metabolic control reflected by HbA1c (with Insuflon, 7.3 +/- 2.6%; without, 7.1 +/- 2.2%), 24-h profiles of blood glucose and free insulin, 24-h samples of glucosuria, or ketonuria. Weight, insulin doses per kilogram per 24 h, and insulin antibodies were all the same in the two groups.. The long- and short-term metabolic control of IDDM was not altered by the use of indwelling catheters for insulin injections. Insuflon can be offered as an alternative to patients with IDDM who find regular injections uncomfortable. Topics: Adolescent; Blood Glucose; Body Weight; C-Peptide; Catheters, Indwelling; Child; Cross-Over Studies; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Insulin Infusion Systems | 1994 |
Evidence for a short-term stimulatory effect of insulin on cholesterol synthesis in newly insulin-treated diabetic patients.
To gain further insight into the effects of insulin on cholesterol synthesis in humans, 19 newly insulin-treated diabetic patients were studied before any insulin treatment (study day 1) and after a few days of optimized glycemic control with a continuous intravenous insulin infusion (study day 2). The patients were divided into two groups according to their clinical characteristics and laboratory disorders. Groups I and II consisted, respectively, of 10 newly diagnosed type I diabetic patients and nine type II diabetic patients with secondary failure to oral antidiabetic drugs. Cholesterol synthesis was estimated from the determination of serum lathosterol, a metabolic precursor in the cholesterol pathway, and from the serum lathosterol to cholesterol ratio. Serum cholesterol (millimolar, mean +/- SEM) remained unchanged in both groups. After insulin therapy (study day 2), serum lathosterol (micromolar) and the serum lathosterol to cholesterol ratio (molar ratio x 10(3)) were significantly increased as compared with baseline (study day 1). Serum lathosterol levels were as follows: 9.9 +/- 2.0 versus 4.1 +/- 0.4 (P < .02) in group I, and 9.9 +/- 0.8 versus 5.7 +/- 0.7 (P < .005) in group II; serum lathosterol to cholesterol ratios were 2.10 +/- 0.39 versus 0.86 +/- 0.11 (P < .005) in group I, and 1.92 +/- 0.12 versus 0.98 +/- 0.10 (P < .001) in group II. The data indicate that in newly insulin-treated diabetic patients, short-term intensive insulin therapy has a stimulatory effect on cholesterol synthesis and even results in cholesterol overproduction. Topics: Adolescent; Adult; Aged; Apolipoproteins; Blood Glucose; C-Peptide; Child; Cholesterol; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Isomerism; Male; Middle Aged; Triglycerides | 1994 |
Combination of nicotinamide and steroid versus nicotinamide in recent-onset IDDM. The IMDIAB II Study.
The aim of this study was to compare the effect of nicotinamide (NCT) alone or in combination with a cortisone-like substance, deflazacort (DFL), on the integrated parameters of metabolic control in patients with the recent-onset of insulin-dependent diabetes mellitus (IDDM).. Thirty-six patients who were diagnosed with diabetes between 5 and 35 years of age entered a randomized, double-blind, 1-year prospective study. Group A (n = 18) received NCT for 1 year (25 mg.kg-1.day-1) plus DFL for 3 months (0.6 mg.kg-1.day-1 in the first month, 0.3 mg.kg-1.day-1 in the other 2 months). Group B (n = 18) received NCT for 1 year (25 mg.kg-1.day-1) plus placebo for the first 3 months. All patients were treated with intensified insulin therapy.. At 3 months after diagnosis, the insulin dose was significantly higher in group A compared with group B (P < 0.03) with similar HbA1 levels. Basal and stimulated C-peptide levels in group A of both adults and children were significantly higher compared with patients of group B (P < 0.05 and P < 0.03, respectively). At the end of a 1-year follow-up, basal C-peptide did not differ between the two groups, although stimulated C-peptide was still significantly higher in patients of group A compared with group B (P < 0.05). Finally, insulin requirement did not differ between the two groups.. A short-term course of DFL therapy at diagnosis in addition to NCT slightly increases glucagon-stimulated but not basal beta-cell function after 1 year. Topics: Adolescent; Adult; Age Factors; Anti-Inflammatory Agents; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Follow-Up Studies; Glucagon; Glycated Hemoglobin; Humans; Insulin; Male; Niacinamide; Pregnenediones | 1994 |
Altered postprandial insulin requirement in IDDM patients with gastroparesis.
To evaluate the effect of gastric emptying on postprandial insulin requirement in insulin-dependent diabetes mellitus (IDDM) patients with and without gastroparesis.. Postprandial insulin requirement and gastric emptying were simultaneously evaluated in five IDDM patients with gastroparesis and in six control IDDM patients without gastroparesis. Postprandial insulin requirement after test-meal intake was assessed by measuring the insulin infusion rate during a 4-h feedback control with an artificial endocrine pancreas device (Biostator, Life Science Instruments, Miles, Elkhart, IN). Gastric solid and liquid emptyings were evaluated during the Biostator study by measuring the disappearance rate of 99mTc in the stomach and in the time course of plasma acetaminophen concentration, respectively.. Total insulin requirement during the first 120 min after the test-meal intake was significantly lower in the gastroparetic patients than in the control patients. The gastroparetic patients showed no apparent postprandial peak for insulin infusion rate during the 4-h study, although the peak rate was observed within 120 min after the test-meal intake in the control patients. The disappearance of 99mTc in the stomach was significantly slower, and plasma acetaminophen concentrations were significantly lower in the gastroparetic patients compared with those in the control patients, respectively.. The results suggest that IDDM patients with gastroparesis, accompanied by impaired solid and liquid emptying, have an altered postprandial insulin requirement. Topics: Adult; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Eating; Feedback; Female; Gastric Emptying; Gastroparesis; Glycated Hemoglobin; Humans; Male; Middle Aged; Time Factors | 1994 |
Transplantation of porcine fetal pancreas to diabetic patients.
Transplantation of fetal porcine islet-like cell clusters (ICC) reverses diabetes in experimental animals. We have now transplanted porcine ICC to ten insulin-dependent diabetic kidney-transplant patients. All patients received standard immunosuppression and, at ICC transplantation, antithymocyte globulin or 15-deoxyspergualin. ICC were injected intraportally or placed under the kidney capsule of the renal graft. Four patients excreted small amounts of porcine C-peptide in urine for 200-400 days. In one renal-graft biopsy specimen, morphologically intact epithelial cells stained positively for insulin and glucagon in the subcapsular space. We conclude that porcine pancreatic endocrine tissue can survive in the human body. Topics: Adult; Animals; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Tissue Transplantation; Graft Survival; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Pilot Projects; Swine; Transplantation, Heterologous | 1994 |
Insulin secretion, insulin action and non-insulin-dependent glucose uptake in pancreas transplant recipients.
To assess individual factors responsible of overall glucose tolerance after successful pancreas transplantation, an i.v. glucose tolerance test, with frequent blood sampling and tolbutamide administration to elicit a second insulin response was used to estimate insulin sensitivity (SI) and glucose effectiveness (SG) with Bergman's minimal model. Insulin secretion was calculated from the combined insulin-C-peptide kinetics method. These parameters were quantified in identically immunosupressed transplants: ISPx, four segmental pancreas recipients with impaired glucose tolerance; TSPx, five segmental pancrease recipients with normal glucose tolerance; WPx, five whole pancreas recipients with normal glucose tolerance; and in two controls groups, Kx, eight nondiabetic kidney recipients, and Ns, eight normal subjects. All participants had normal fasting plasma glucose and normal glycosylated hemoglobin A1C levels. The glucose tolerance KG value was significantly reduced only in ISPx compared with Ns (P < 0.05). SI was reduced by 60% in ISPx, WPx, and Kx compared with normal subjects (P < 0.05), whereas SI was reduced by 30% in TSPx compared with normal controls (P = NS). The reduction in SG was the same in all pancreas transplanted groups, as compared to Kx and Ns (by 33% and 40%, respectively, P < 0.05). The first-phase insulin secretion (0-5 min) was markedly reduced in ISPx and TSPx compared with Ns (by 76% and 50%), to Kx (by 84% and 66%) and to WPx (by 73% and 45%), respectively (P < 0.05), but similar to Ns in WPx. The overall incremental insulin secretion was reduced in ISPx compared with Ns, WPx, and Kx (by 38%, 62%, and 73%, respectively, P < 0.05) and reduced in TSPx compared to WPx and Kx (by 47% and 67%, respectively, P < 0.05) Ns secreted 43% of the total amount of insulin during the first phase the corresponding value was only 13% in ISPx vs. 24% in TSPx, 24% in Kx, and 25% in WPx, respectively (P < 0.05). In conclusion, after pancreas transplantation, the overall glucose tolerance is determined by the net effect of reductions in insulin sensitivity and glucose effectiveness and in the adaptability of the beta-cells to ensure sufficient insulin secretion. beta-cell function was impaired in both the whole pancreas and segmental transplant recipients, and the failure to increase insulin secretion sufficiently leads to glucose intolerance. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Kidney Transplantation; Kinetics; Male; Middle Aged; Pancreas Transplantation; Tolbutamide | 1994 |
Islet cell antibodies, but not glutamic acid decarboxylase antibodies, are decreased by plasmapheresis in patients with newly diagnosed insulin-dependent diabetes mellitus.
The effects of plasmapheresis on islet autoantibody levels, C-peptide (beta-cell function), and hemoglobin-A1c (HbA1c, metabolic control) were tested in a prospective blinded study of 18 newly diagnosed insulin-dependent diabetes mellitus (IDDM) patients randomly assigned to receive plasmapheresis (P), carried out as double filtration, or sham (S) treatment at diagnosis and 3 months thereafter. At diagnosis, 6 of 8 patients (75%) in group P and 9 of 10 patients (90%) in group S had islet cell antibodies (ICA), whereas 4 of 8 (50%) and 7 of 10 (70%) patients, respectively, had glutamic acid decarboxylase antibodies (GAD65-Ab), with no significant differences between the groups in ICA and GAD65-Ab levels. After 6 months, P patients showed significantly lower ICA levels than S patients (11 +/- 6 and 128 +/- 47 Juvenile Diabetes Foundation International Units, respectively; P < 0.02) due to an increase in ICA levels in 8 of 9 (88%) of the S patients not seen in P patients (P < 0.002). Concurrently, HbA1c stabilized in P, but not in S, patients and was significantly lower by 24 months (6.58 +/- 0.54% vs. 9.76 +/- 1.21%; P < 0.05). Moreover, fasting C-peptide increased significantly (214 +/- 11 pmol/L; P < 0.05) over the first 6 months in P. After the initial 6 months, ICA levels tended to decrease in all patients and were not detected after 60 months. GAD65-Ab levels were not influenced by plasmapheresis and, also in contrast to ICA, increased significantly (P < 0.05) in the whole study population after 60 months. In fact, 4 initially negative patients became GAD65-Ab positive after diagnosis (in 2 patients > 24 months after diagnosis). We conclude that plasmapheresis of newly diagnosed IDDM patients does not change subsequent GAD65-Ab levels, but ICA are significantly decreased with associated improved C-peptide and HbA1c levels. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Plasmapheresis | 1994 |
The use of glipizide combined with intensive insulin treatment for the induction of remissions in new onset adult type I diabetes.
To determine if glipizide could enhance remission induction in new onset type 1 diabetes compared to intensive insulin treatment alone, 27 patients with type 1 diabetes were intensively treated in an open randomized trial with subcutaneous injections for one month. The insulin was randomly either discontinued (Group A) or the insulin discontinued and glipizide begun (Group B) Three patients in Group A (22%) and 7 in Group B (54%, p < .05) underwent insulin-free remissions for 10.3 +/- 4.4 and 8.7 +/- 2.6 months, respectively (p = NS). Mean blood glucose levels during insulin treatment were lower in patients entering remissions (94 +/- 3 mg/dl versus 102 +/- 5 mg/dl, p < 0.05). C-peptide levels were performed 0, 4, 8, and 24 weeks after insulin treatment. When all patients were examined, mean stimulated C-peptide levels at 4 weeks (0.58 +/- 0.09 pm/ml) were increased compared to time 0 (0.32 +/- 0.05 pm/ml, p < 0.02). Patients not entering remission had higher 4-week stimulated values (0.67 +/- 0.12 pm/ml) compared to time 0 values (0.29 +/- 0.06 pm/ml, p < .01), whereas remission patients' mean C-peptide levels remained similar at 0, 4, 8 and 24 weeks. These data indicate that a) insulin treatment plus glipizide induces higher rates of remission compared to intensive insulin treatment alone, b) the intensity of initial metabolic control may be an important determinant for remission induction, and c) endogenous insulin secretion is not associated with remission induction, suggesting that glipizide alters insulin sensitivity or is immunomodulatory in the context of new onset type 1 diabetes. Topics: Adult; Age of Onset; Algorithms; Blood Glucose; C-Peptide; Combined Modality Therapy; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Glipizide; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Male; Remission Induction; Weight Gain | 1993 |
Effects of a short prednisone regime at clinical onset of type 1 diabetes.
The effect of corticosteroids on beta cell function and humoral immune response in type 1 diabetes was tested in a 2-month trial conducted on 32 newly diagnosed patients (age 22.8 +/- 1.4 years, mean +/- S.E.M.). Prednisone was administered at immunosuppressive dosage (1 mg.kg-1.day-1) during the initial 10 days and at a maintenance dosage (0.3 mg.kg-1.day-1) for 50 days. Patients (n = 32) were enrolled within 6 weeks after diagnosis and matched in pairs for age, sex, presence of islet cell antibodies (ICA) and glucagon stimulated C-peptide levels. Insulin discontinuation was not contemplated. All the patients who received prednisone became ICA during treatment but in some (4 out of 10) this effect was only transient. Insulin antibodies (IA) were significantly lower in the prednisone group at second and third month (P < 0.05). No patient experienced complete remission but in 10 prednisone and 4 control patients the insulin requirements were below 0.3 IU/kg (P < 0.05). With similar glycemia the fasting C-peptide levels were higher in the treated patients. The profile of the insulin requirements during the follow-up was different in the two groups and at 9 months the prednisone group needed less insulin than the control (P < 0.05). Interestingly, within the prednisone-treated group and after 6 months, the levels of stimulated C-peptide improved significantly among the ICA+ patients while they were steady or declined in ICA- (P < 0.01). The analysis of variance covariance confirmed a positive interaction between ICA and the administration of prednisone on the outcome of beta cell function.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Analysis of Variance; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Histocompatibility Testing; Humans; Immunosuppressive Agents; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Multivariate Analysis; Prednisone; Prospective Studies; Time Factors | 1993 |
Glycemic actions of alanine and terbutaline in IDDM.
To test the hypothesis that the amino acid Ala and the beta 2-adrenergic agonist terbutaline raise plasma glucose concentrations substantially, and do so through different mechanisms, in IDDM patients.. We administered these (Ala: 20 and 40 g, orally; terbutaline: 2.5 and 5.0 mg orally and 0.25 mg subcutaneously) and placebos in random sequence to 6 nondiabetic subjects and 6 insulin-infused, initially euglycemic IDDM patients, each studied on six different occasions. Inhaled terbutaline, 0.4 mg, was also tested on a seventh occasion in IDDM patients.. Ala administration raised plasma glucagon (P = 0.0219), C-peptide (P = 0.0014), and insulin (P = 0.0094), with no significant change in plasma glucose, in nondiabetic subjects. In patients with IDDM it raised glucagon (P = 0.0001), but not C-peptide or insulin, and plasma glucose rose to 8.3 +/- 0.3 (Ala 20 g, P = 0.0006) and 10.0 +/- 1.0 mM (Ala 40 g, P = 0.0094). Catecholamine levels were unchanged. Terbutaline ingestion raised plasma glucose minimally (e.g., to 6.3 +/- 0.3 mM, P = 0.0133) in nondiabetic subjects but substantially, to 10.2 +/- 1.0 (terbutaline 2.5 mg, P = 0.0078) and 14.0 +/- 0.6 mM (terbutaline 5.0 mg, P = 0.0001), in IDDM patients; subcutaneous terbutaline raised plasma glucose (to a peak of 10.3 +/- 0.7 mM, P = 0.0017) with an initial effect within 10 min, but inhaled terbutaline did so more slowly. In addition to its direct glycemic actions, terbutaline stimulated sympathetic neural norepinephrine release (P = 0.0151) and increased nonesterified fatty acid levels (P = 0.0104), potential indirect glycemic actions. Glucagon levels were unchanged; insulin levels increased in the nondiabetic subjects.. These data demonstrate substantial glycemic responses to Ala and terbutaline, through different mechanisms, in IDDM patients. Thus, Ala and terbutaline represent potential new approaches to the treatment, and perhaps the prevention, of iatrogenic hypoglycemia in IDDM. Topics: Administration, Oral; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Glucagon; Humans; Injections, Subcutaneous; Insulin; Kinetics; Lactates; Random Allocation; Reference Values; Terbutaline | 1993 |
Alanine and terbutaline in treatment of hypoglycemia in IDDM.
To test the hypothesis that, in contrast to administration of glucose or glucagon, administration of the amino acid Ala or of the beta 2-adrenergic agonist terbutaline produces sustained glucose recovery from hypoglycemia.. We developed a model of clinical hypoglycemia using subcutaneous injection of insulin (0.15 U/kg) in patients with IDDM. In comparison with nondiabetic subjects, patients with IDDM exhibited reduced glucagon (P = 0.0001), epinephrine (P = 0.0060), and pancreatic polypeptide (P = 0.0001) responses to hypoglycemia. In addition to placebos, the following were administered during hypoglycemia (2 h after insulin injection) in IDDM patients: oral glucose, 10 and 20 g; subcutaneous glucagon, 1.0 mg; oral Ala, 40 g; oral terbutaline, 5.0 mg; and subcutaneous terbutaline, 0.25 mg.. Glucose (10 and 20 g) and glucagon raised plasma glucose (P = 0.0163, 0.0060, and 0.0001, respectively) from 3.0-3.3 mM to peaks of 5.4 +/- 0.4, 6.8 +/- 0.7, and 11.8 +/- 0.8 mM within 30, 45, and 60 min, respectively, but the responses were transient. Oral Ala raised glucose levels (P = 0.0401) to 4.0 +/- 0.4 mM within 30 min; glucose levels then rose gradually to a 6-h value of only 7.1 +/- 0.9 mM. Oral terbutaline raised glucose levels (P = 0.0294) to 4.3 +/- 0.3 mM within 30 min; glucose levels then rose substantially. In contrast, subcutaneous terbutaline raised glucose levels (P = 0.0249) to 3.7 +/- 0.1 mM within 15 min; the levels plateaued at 5.0 mM from approximately 60-150 min and then paralleled the placebo curve.. Ala and terbutaline produce sustained glucose recovery from hypoglycemia in IDDM and are therefore potentially useful agents for the treatment of mild or moderate iatrogenic hypoglycemia, or the prevention of iatrogenic hypoglycemia, when food intake is not anticipated over the following several hours. Topics: 3-Hydroxybutyric Acid; Administration, Oral; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Glucagon; Humans; Hydroxybutyrates; Hypoglycemia; Injections, Subcutaneous; Insulin; Lactates; Pancreatic Polypeptide; Terbutaline; Time Factors | 1993 |
Influence of combined C-peptide and insulin administration on renal function and metabolic control in diabetes type 1.
The possible influence of C-peptide on renal function and metabolic control in patients with type 1 diabetes was examined in a double blind, randomized study. Nine patients received insulin and equimolar amounts of biosynthetic human C-peptide for 1 month (group 1), and nine were given insulin only (group 2). C-Peptide levels in plasma ranged from 0.3-2.6 nmol/L in group 1 during the study, whereas group 2 had undetectable levels. The urinary excretion of albumin in group 1 was 21 +/- 6 micrograms/min before the study and decreased by 40% and 55% after 2 and 4 weeks, respectively (P < 0.05). No change was seen in group 2. The glomerular filtration rate fell by 6% after 2 and 4 weeks (P < 0.05) in group 1, whereas no change was observed in group 2. Fluorescein leakage across the blood-retinal barrier decreased by 30% in group 1 (P < 0.05) and was unaltered in group 2. Hemoglobin-A1c and fructosamine values decreased by 9-16% in group 1 (P < 0.05), but not in group 2. The findings suggest that administration of C-peptide plus insulin, compared to insulin alone, to type 1 diabetic patients may reduce glomerular permeability and improve metabolic control. Topics: Adolescent; Adult; Albuminuria; Blood Glucose; Blood-Retinal Barrier; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Fluorescein; Fluoresceins; Fructosamine; Glomerular Filtration Rate; Glucagon; Glycated Hemoglobin; Growth Hormone; Hexosamines; Humans; Insulin; Insulin Infusion Systems; Kidney; Male; Norepinephrine; Pilot Projects | 1993 |
Determinants of clinical remission in recent-onset IDDM.
To assess the relationship of SI and insulin secretion (C-peptide levels) to remission status in recent-onset IDDM.. We followed 22 newly diagnosed patients, of whom 16 received immunomodulatory treatment with low-dose (5 mg.kg-1 x day-1) CsA and/or short-term (72 h) methylprednisolone and 6 received standard insulin treatment, at 3-mo intervals for 12 mo. Insulin secretion was assessed by C-peptide levels and AIRglu, which was determined as the area under the insulin response curve, above the fasting level, from 0-10 min after a 0.3 g.kg-1 x i.v. glucose bolus. SI was assessed by the minimal model technique applied to a frequently sampled IVGTT. Clinical remission was defined in those patients who maintained normal range GHb and capillary blood glucose levels < 7.8 mM premeal without insulin therapy for a minimum of 14 days.. The rate of clinical remission was not different with immunomodulatory treatment; nor were the metabolic parameters of plasma C-peptide levels, AIRglu, and SI different in the treatment groups. The mean plasma C-peptide level improved significantly at 3 mo and was maintained to 12 mo. AIRglu was grossly subnormal throughout, but a significant improvement was seen at 3 and 6 mo. Mean SI was normalized at 3 and 6 mo but not maintained beyond 9 mo. The maximum rate of clinical remission was seen at 6 mo.. Clinical remission in recent-onset IDDM patients is associated with improvement in both insulin secretion and SI. Although the improvement in basal C-peptide persisted, AIRglu increased only transiently and declined as loss of remission occurred in most patients. Loss of remission to an insulin-requiring state is associated with a decrease in SI. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Immunotherapy; Insulin; Insulin Secretion; Methylprednisolone | 1993 |
Improvement of diabetic control and acceptability of a three-injection insulin regimen in diabetic adolescents. A multicenter controlled study.
To compare the effectiveness and acceptability of a three-injection insulin regimen with the conventional two-injection therapy in an unselected population of diabetic adolescents.. Some 205 patients aged 10-18 yr with IDDM, who were previously treated with two daily insulin injections, were included without any selection into a randomized trial. They were either switched to three (regular prebreakfast, regular prelunch, and [regular+ultralente] predinner) or remained on two ([regular+intermediary] prebreakfast and predinner) subcutaneous injections. They were evaluated after 1 yr of treatment. The major criteria of outcome of efficacy were the concentration of GHb, the frequency of severe hypoglycemia and DKA, and body weight.. Of the patients, 82% accepted the three-injection regimen, and 83% accepted the two-injection regimen. At entry into the trial, no significant differences appeared between the two treatment groups nor among patients refusing the allocated regimen. Significant explanatory variables predicting initial diabetes control were duration of disease and adherence to diet. GHb, decreased from 9.8 +/- 0.1 to 9.3 +/- 0.2% (P < 0.05) in the three-injection group, whereas it increased from 9.5 +/- 0.3 to 9.8 +/- 0.3% (P < 0.05) in the two-injection group, resulting in a modest (0.75%) but significant difference (P < 0.05) between GHb change in the two groups. The difference reached 1.4% (P < 0.0002) in patients with GHb > 11.2% at entry. The frequency of hypoglycemia and DKA was similar in the two groups. None of the parameters known to potentially influence glycemic control changed during the trial, and, therefore, the improvement of GHb could be attributed to the pattern of daily insulin distribution per se.. In the general diabetic adolescent population, the efficacy of a three-injection regimen is somewhat superior to that of a conventional two-injection regimen, particularly in patients previously poorly controlled. The acceptability of this regimen being excellent, its increased use should be considered in this age-group. Topics: Adolescent; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diet, Diabetic; Drug Administration Schedule; Family; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Interpersonal Relations; Male; Patient Compliance; Patient Education as Topic; Psychological Tests; Self Concept; Socioeconomic Factors; Surveys and Questionnaires; Treatment Refusal | 1993 |
Immunoprotection in spontaneous remission of type 1 diabetes: long-term follow-up results.
This prospective pilot study was undertaken to test the efficacy of oral methyl-prednisolone (MP) therapy at spontaneous remission phase of type 1 diabetes in intervening the course of the disease. Twenty-five type 1 diabetic patients who were classified as having a spontaneous remission (honeymoon) were divided into treatment and non-treatment groups on voluntary basis. Fifteen patients thus making up the treatment group (13 males and 2 females, mean age 23.8 +/- 6.2 years) received 0.7-1.0 mg/kg/day of MP p.o. for 2 weeks. The dose of the drug was then gradually diminished every week until 5 mg/day (approx. 0.1 mg/kg/day) and discontinued at 10 +/- 2 weeks. In case of hyperglycemia occurring in 12 of 15 patients due to the administration of steroid, insulin was used to normalize blood glucose levels (average 0.47 +/- 0.21 IU/kg/day). The non-treatment group (8 males and 2 females, mean age 21.8 +/- 8.9) did not receive any special medication or placebo except for insulin whenever necessary to regulate glycemia. Upon completion of protocol, all patients in treatment group displayed clinical remission with 10 still in non-insulin requiring remission for follow-up periods ranging between 16 and 91 months. The remaining 5 patients relapsed within 3-15 months of therapy. Other metabolic (including basal and stimulated C-peptide levels) and immunological indices that have spontaneously ameliorated with the occurrence of honeymoon were also maintained within normal range in the NIR patients. Meanwhile, natural remission in the non-MP-treated group terminated at 3.4 +/- 0.6 months with deterioration of all metabolic and immunological markers as well as increasing requirements for insulin. In conclusion, the spontaneous remission of the patients could be prolonged significantly by MP therapy as opposed to no therapy (P < 0.001). These results suggest that the spontaneous remission phase may be a crucial point of intervention in immunotherapy of type 1 diabetes and that randomized trials with MP at this particular phase would be worthwhile. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Follow-Up Studies; Glycated Hemoglobin; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Islets of Langerhans; Male; Methylprednisolone; Pilot Projects; Prospective Studies; Remission, Spontaneous; T-Lymphocytes | 1993 |
Complex carbohydrates in the prevention of nocturnal hypoglycaemia in diabetic children.
In order to prevent nocturnal hypoglycaemia in patients with insulin-dependent diabetes mellitus with complex carbohydrates a pilot-study was designed with nine children with ages of 9-18 years. The children were admitted twice to the hospital (control and test) and remained the evening, night and morning the following day. The standard evening snack, given on the control day, was replaced on the test day by a test snack which contained a solution of uncooked cornstarch as a source of complex carbohydrates. The carbohydrate content of the test snack was maintained but did not contain mono- and disaccharides. Blood samples were collected and when the child had blood glucose concentrations of < or = 3.0 mmol/l or showed clinical symptoms of impending hypoglycaemia, intervention occurred with extra carbohydrates. Six out of nine children needed intervention after the standard snack (blood glucose concentrations were 1.8, 2.7, 3.0, 3.6 and 3.7 mmol/l). After the test snack this was four out of nine (blood glucose concentrations were 2.3, 2.6, 3.2 and 3.2). Three children needed a second intervention after the standard snack versus two after the test snack. One child needed a third intervention after the standard snack. The time of intervention ranged from 11 p.m. to 4 a.m. and from 10 p.m. to 12 a.m., respectively, on the day of the standard and test snack. Raw cornstarch, as a source of complex carbohydrates, did not prevent nocturnal hypoglycaemia in the dose used but blood glucose levels dropped more slowly than those after the standard snack.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child Nutritional Physiological Phenomena; Diabetes Mellitus, Type 1; Dietary Carbohydrates; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Male; Starch; Time Factors | 1993 |
Double-blind randomized trial of nicotinamide on early-onset diabetes.
To determine the efficacy of nicotinamide in inducing remission in early-onset insulin-dependent diabetes mellitus.. This study was a double-blind, randomized clinical trial.. Nicotinamide failed to induce remission or differences on beta-cell secretion between the two groups. Topics: Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Double-Blind Method; Glycated Hemoglobin; Humans; Niacinamide; Remission Induction | 1992 |
Natural course of remission in IDDM during 1st yr after diagnosis.
To describe the natural course of clinical remission in insulin-dependent diabetes mellitus (IDDM) when insulin dose is minimized without loss of target glycemia and to identify factors that predict clinical remission.. Ninety-five patients, who were placebo-treated control subjects in the Canadian-European multicenter randomized trial of cyclosporin A in recent-onset IDDM, were studied.. The mean insulin dose decreased during the first months after diagnosis, with a nadir at 3 mo, when 27% of the patients did not require insulin to maintain target glycemia. At 1 yr, 10% of patients still did not need insulin. Patients not receiving insulin who had glycosylated hemoglobin within the normal range were called remitters. Mean basal and glucagon-stimulated C-peptide values were significantly (P less than 0.025) higher in remitters than nonremitters at the start of the study. Therefore, all patients were divided into those with values above the mean stimulated C-peptide (0.4 nM) and those with values below the mean at entry. The probability of entering a remission with a stimulated C-peptide greater than 0.4 nM was 10 times as high (P less than 0.05) as for those with a stimulated C-peptide below this level. Surprisingly, the beginning and end of the remission were associated with neither major changes in C-peptide levels nor islet cell antibody and insulin-antibody titer. A more rapid loss of stimulated C-peptide occurred in patients who lacked HLA-DR3 and -DR4 (P less than 0.05 at mo 9).. This study shows a higher spontaneous clinical remission rate than expected during the 1st yr after diagnosis. Preserved beta-cell function at entry predicts a greater chance of entering a remission, and a more rapid loss of beta-cell function was seen in patients without HLA-DR3 and -DR4. Topics: Adult; Autoantibodies; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Probability; Remission, Spontaneous | 1992 |
Randomised prospective study of short-term and long-term initial stay in hospital by children with diabetes mellitus.
To assess how an isolated change in the pattern of care influences outcome of care and hospital use, a randomised prospective 2-year study was done in which 31 of 61 consecutive children with newly diagnosed insulin-dependent diabetes mellitus (IDDM) were admitted to hospital at disease onset for about a week and compared with the other 30 children who were admitted for about 4 weeks. Insulin treatment and education about diabetes were similar in the two groups. Duration of initial stay in hospital had no effect on metabolic control during the 2 years but time since diagnosis was significant with respect to effect on haemoglobin A1 (p = 0.001), haemoglobin A1c (p = 0.004), and insulin dose (p less than 0.001). At 2 years, 45% of the children in the short-term group and 29% in the long-term group were C-peptide positive (p = NS); C-peptide positivity correlated with age. A change in the pattern of care of children with IDDM, led to a pronounced decrease in hospital use by this patient group. Irrespective of the length of initial stay in hospital, equally good metabolic control was obtained in both groups for 2 years. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Administration Schedule; Evaluation Studies as Topic; Female; Finland; Glycated Hemoglobin; Humans; Incidence; Infant; Infant, Newborn; Insulin; Length of Stay; Male; Patient Education as Topic; Prospective Studies; Time Factors | 1991 |
Long-term follow-up of glycaemic control and parameters of lipid transport after pancreas transplantation.
We report the long-term metabolic observations made on 37 patients after simultaneous pancreas and kidney transplantation. Plasma C-peptide levels were above the physiological range in all patients and there was no significant difference between patients undergoing delayed duct occlusion (n = 12) or those with drainage of exocrine secretion into the urinary bladder (n = 25). HbA1c was equally at the upper end of the normal range in both subsets of patients. Mean fasting cholesterol (237 mg/dl) and triglycerides (122 mg/dl) were normal, and HDL-cholesterol was above normal with an average concentration of 77 mg/dl. Two patients underwent an oral fat tolerance test and showed extremely low postprandial lipaemia and very high lipoprotein lipase activities. We conclude that patients with a functioning pancreas graft persistently demonstrate normoglycaemia, elevated C-peptide, and a very favourable lipid profile both in the fasting and the postprandial state. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Kidney Failure, Chronic; Kidney Transplantation; Lipids; Pancreas Transplantation | 1991 |
Results of our first nine intraportal islet allografts in type 1, insulin-dependent diabetic patients.
With the first demonstration of insulin independence following intraportal islet transplantation into a patient with type 1 diabetes, a new era of clinical islet transplantation will begin. This report provides our initial experience of clinical islet transplantation with a total of nine consecutive portal vein islet transplants in seven diabetic recipients. The first three transplants were done in nonrenal failure diabetics (NRFI) using 6319 +/- 2173 islets/kg body weight with islets processed from single pancreas and cultured for 7 days at 24 degrees C. Prednisone, azathioprine, and cyclosporine were initiated prior to transplant. While all three recipients demonstrated C-peptide function posttransplant, all three rejected their grafts at 2 weeks. Five days of OKT3 treatment failed to recover more than 10% of their rejecting islet grafts. The studies were then shifted to established kidney transplant recipients (EKI) maintaining their basal immunosuppression while adding 7 days of Minnesota antilymphoblast globulin (MALG) to the recipient using islets from single donor pancreas that had been cultured for 7 days at 24 degrees C. There were an average of 6161 +/- 911 islets transplanted intraportally into three EKI recipients. All three had C-peptide response from the transplant, but none achieved insulin independence. While the first patient rejected his graft at 2 weeks, two recipients demonstrated long-term islet function up to 10 months posttransplant. Sustacal challenge testing demonstrated C-peptide responsiveness, but in a delayed pattern suggesting insufficient islet mass had been transplanted. The next three kidney transplant recipients received islets from more than one donor pancreas averaging 13,916 +/- 556 islets/kg body weight. The first of these was the first to achieve insulin independence from 10 to day 25 posttransplant when she appeared to have a rejection episode. The second and third recipients were retransplanted with islets from multiple donors having achieved partial islet function from single pancreas donor. The first patient on triple immunosuppression is demonstrating long-term partial function at 184 days but is not insulin independent. The third patient on prednisone and azathioprine received one half his islets after 7-day culture and the other half after 7-day culture combined with cryopreservation. He is continuing to demonstrate insulin independence for 154 days post-transplant with a glycated hemoglobin value of 5.6%. Sus Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Kidney Transplantation; Portal Vein; Transplantation, Homologous | 1991 |
Interaction of bromocriptine and cyclosporine in insulin dependent diabetes mellitus: results from the Canadian open study.
Although cyclosporine A (Cy-A) is effective in modifying the initial course of newly diagnosed insulin dependent diabetes mellitus (IDDM) it has a number of side effects, particularly renal, which limit its use. In this study we investigated the potential synergistic effects of bromocriptine (BCR) therapy in treating patients with newly diagnosed IDDM. Three groups of patients were treated: (1) fourteen patients on Cy-A who required a decrease in their dose due to elevated creatinine; (2) four newly diagnosed patients whose initial therapy consisted of low dose (5 mg/kg/day) Cy-A and 10 mg/day of BCR; (3) eight patients whose glucagon-stimulated connecting-peptide (C-peptide) levels were greater than 0.3 nmol/l but whose insulin requirements were over 0.3 U/kg/day and whose Cy-A was to be discontinued. The results suggest that there was no statistically significant difference in stimulated C-peptide, glycosylated haemoglobin, daily insulin dose or serum creatinine. However, the trend suggested that BCR may have some protective effect on preserving endogenous insulin secretory capacity, although glycosylated haemoglobin and daily insulin dose increased. The results do not suggest that patients with newly diagnosed IDDM significantly benefit from concurrent BCR and Cy-A therapy. Topics: Blood Glucose; Bromocriptine; C-Peptide; Creatine; Cyclosporins; Diabetes Mellitus, Type 1; Drug Synergism; Drug Therapy, Combination; Glycated Hemoglobin; Humans; Pilot Projects | 1990 |
Wisconsin Epidemiologic Study of Diabetic Retinopathy. XII. Relationship of C-peptide and diabetic retinopathy.
The relationship between plasma C-peptide and the frequency and severity of diabetic retinopathy was examined in a population-based study in Wisconsin in 1984-1986. Individuals with younger- (n = 835) and older- (n = 940) onset diabetes were included. C-peptide was measured by radioimmunoassay with Heding's M1230 antiserum. Retinopathy was determined from stereoscopic fundus photographs. The highest frequencies and most severe retinopathy were found in insulin-using individuals with undetectable or low plasma C-peptide (less than 0.3 nM), whereas the lowest frequencies of retinopathy were found in older-onset overweight individuals not using insulin. In older-onset individuals using insulin, having no detectable C-peptide was significantly associated with the presence of proliferative retinopathy. Otherwise, within each group (younger onset using insulin, older onset using insulin, and older onset not using insulin), after controlling for other characteristics associated with retinopathy, there was no relationship between higher levels of C-peptide and lower frequency of or less severe retinopathy. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Diagnosis-Related Groups; Humans; Incidence; Insulin; Insulin Secretion; Radioimmunoassay; Sampling Studies; Wisconsin | 1990 |
A trial of nicotinamide in newly diagnosed patients with type 1 (insulin-dependent) diabetes mellitus.
Various agents have been tried in subjects with newly diagnosed Type 1 (insulin-dependent) diabetes mellitus in an attempt to preserve Beta-cell function. In this double-blind study, nicotinamide or placebo were given for one year to 35 children and adolescents with newly-diagnosed Type 1 diabetes. All subjects were within six weeks of diagnosis and were between the ages of 6 and 18 years. Nicotinamide, a poly-(ADP-ribose) synthetase inhibitor, was given in a dose of 100 mg/year of age up to a maximum of 1.5 g/day. There were no initial differences between the 17 control and the 18 test subjects in relation to mean age, sex distribution, or severity at onset. Mean insulin dosages and HbA1 values were similar for the two groups during the year of study. Fasting and glucagon-stimulated C-peptide levels were similar for the control and nicotinamide treated groups at the beginning and after 4 and 12 months. There were no differences in remission rates between the two groups. Nicotinamide, at this dosage, does not preserve residual insulin secretion in subjects with newly diagnosed Type 1 diabetes. Topics: Adolescent; C-Peptide; Child; Clinical Trials as Topic; Delayed-Action Preparations; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Niacinamide; Random Allocation | 1990 |
Atrial natriuretic peptide in patients with diabetes mellitus type I. Effects on systemic and renal hemodynamics and renal excretory function.
In the present study the effects of 1 h intravenous infusion of alpha-human atrial natriuretic peptide (24 ng/min/kg) on systemic and renal hemodynamics and on renal excretory function were studied in six insulin-treated and metabolically well-controlled patients with diabetes mellitus (DM) type I and in six healthy control subjects (C). Basal plasma atrial natriuretic peptide (ANP) concentration was 14.6 +/- 2.0 in DM patients and 14.9 +/- 1.3 pmol/L in C and rose similarly in both groups to 87.1 +/- 22.1 and to 86.9 +/- 11.1 pmol/L, respectively, during alpha-hANP infusion (P less than .05). Maximal effects of alpha-hANP occurred between 30 and 60 min after the start of the infusion. Mean arterial pressure (MAP) (83 +/- 5 v 81 +/- 3 mm Hg), heart rate (HR) (63 +/- 2 v 64 +/- 4/min) and total peripheral resistance (TPR) (11 +/- 1 v 10 +/- 1 mm Hg.min/L) remained unaltered in patients with DM. In contrast, in C MAP and TPR decreased from 83 +/- 3 to 77 +/- 2 mm Hg and from 12 +/- 1 to 10 +/- 1 1 mm Hg.min/L, respectively (P less than .05), whereas HR increased from 53 +/- 2 to 59 +/- 3 beats/min (P less than .05). Cardiac output (CO) rose initially by 11% and by 9% in DM and C, respectively. Urine flow increased from 4.1 +/- 0.9 to 11.3 +/- 1.5 mL/min in DM patients and from 3.9 +/- 1.0 to 8.4 +/- 0.8 mL/min in C (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Atrial Natriuretic Factor; C-Peptide; Diabetes Mellitus, Type 1; Hemodynamics; Humans; Infusions, Intravenous; Insulin; Kidney; Male; Sodium; Urodynamics | 1990 |
Different absorption of isophane (NPH) insulin from subcutaneous and intramuscular sites suggests a need to reassess recommended insulin injection technique.
The absorption of isophane (NPH) insulin from subcutaneous and intramuscular injection sites was measured in seven healthy volunteers using the euglycaemic clamp technique. Human Insulatard (Nordisk, Gentofte, Denmark) was administered in a dose of 0.25 U kg-body-weight-1 into the anterior compartment of the thigh. In random order injections were given either subcutaneously, via 12 mm needle at 45 degrees to the skin into a skinfold, or intramuscularly by 25 mm needle perpendicularly to the skin. Insulin concentrations rose more rapidly after intramuscular injection than after subcutaneous injection, being significantly higher as early as 60 min after injection (19.7 +/- 1.6 (+/- SE) vs 8.7 +/- 1.4 mU l-1; p less than 0.001). Thereafter insulin concentrations remained significantly higher for the remaining 360 min of study, reflected by a significantly greater area under the insulin concentration curve for the 420 min study (IM 8630 +/- 1256 vs SC 4908 +/- 465 mU l-1 min, p less than 0.05). A significantly greater quantity of infused glucose was required to maintain euglycaemia after intramuscular injection than after subcutaneous injection (923 +/- 256 vs 216 +/- 71 mg kg-1 min, p less than 0.05). These results demonstrate a striking difference in the pharmacokinetics of an isophane (NPH) insulin when injected into subcutaneous fat and muscle. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Injections, Intramuscular; Injections, Subcutaneous; Insulin, Isophane; Male | 1990 |
Plasma C-peptide levels and clinical remissions in recent-onset type I diabetic patients treated with cyclosporin A and insulin.
Remission from insulin dependency in insulin-treated recent-onset type I (insulin-dependent) diabetic patients can result from a partial recovery of insulin secretion, an improvement in tissue sensitivity to insulin, or both. The same hypothesis must be analyzed when remission occurs in cyclosporin A (CsA)-treated patients. In this study, plasma C-peptide levels were serially measured in the basal state and after stimulation in 219 recent-onset type I diabetic patients; 129 received CsA, and all patients were similarly monitored and insulin treated. The results were analyzed in view of the occurrence of remission. Remission was defined as good metabolic control in the absence of hypoglycemic treatment for greater than or equal to 1 mo. Remission occurred in 44% of the CsA-treated group and lasted for mean +/- SE 10.0 +/- 0.9 mo vs. 21.6% in the non-CsA-treated group with a duration of 4.4 +/- 0.8 mo. Plasma C-peptide levels were initially dramatically lower than normal in both groups in the basal and stimulated states. C-peptide levels increased significantly later, at 3 and 6 mo, in both groups. C-peptide values were proportional to the rates of remission in both groups. In the non-CsA-treated group, C-peptide levels later decreased, and these patients inexorably relapsed to insulin dependency. In contrast, in the CsA-treated group, the initial recovery in insulin secretory capacity was maintained over the 18-24 mo of the study. Furthermore, higher remission rates and longer-lasting remission were obtained in patients who reached higher C-peptide levels at the 3rd mo of treatment.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Eating; Female; Glucagon; Glucose Tolerance Test; Humans; Insulin; Male; Reference Values | 1990 |
Metabolic response to oral challenge of hydrogenated starch hydrolysate versus glucose in diabetes.
Our objective was to determine whether 1) hydrogenated starch hydrolysates (HSHs), bulking/sweetening agents used in hard candies, produce a diminished postmeal glycemic response relative to glucose in individuals with and without diabetes and 2) any diminished glycemia is secondary to altered carbohydrate absorption. This study followed a randomized double-blind crossover design and was performed in 12 individuals with diabetes (6 non-insulin dependent, 6 insulin dependent) and 6 nondiabetic individuals. Each group consisted of 3 men and 3 women, none with known neuropathy. After an overnight fast, each subject was challenged with 50 g of glucose, HSH 5875 (7% sorbitol/60% maltitol), and HSH 6075 (14% sorbitol/78% hydrogenated maltooligosaccharides)/1.73 m2 of body surface area in random order on 3 successive days. Individuals with diabetes were maintained on continuous subcutaneous insulin infusion throughout the study to achieve prechallenge glucose levels between 4.5 and 6.7 mM. For all groups, the order of plasma glucose responses over 5 h postchallenge was glucose greater than HSH 6075 greater than HSH 5875, P less than 0.001 (glucose vs. HSH). Pooled data for all groups for areas under the curve confirmed that HSH 6075 resulted in greater glycemia than HSH 5875 (P less than 0.05). This was reflected in the order of C-peptide responses seen in the nondiabetic and non-insulin-dependent groups (glucose greater than HSH 6075 greater than HSH 5875, P less than 0.001). Breath H2 after glucose was low, whereas HSH 5875 greater than HSH 6075 (P = 0.003). Gastric distress was noticed with all products.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Double-Blind Method; Fasting; Female; Glucose; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged; Random Allocation; Reference Values; Sugar Alcohols | 1990 |
[Effect of pancreatin on diabetes mellitus in chronic pancreatitis].
The effect of pancreatin on insulinopenic diabetes was studied in 10 patients with chronic pancreatitis and exocrine function impairment. All patients were treated for 4 days in a randomized crossover trial with either pancreatin (6 x 2 capsules, 6 x 300 mg/d) or placebo. Blood glucose levels were determined 7 times every day and night. On day 5, the patients were studied by a glucose sensor with adjustment of blood glucose to 120 mg/dl until 8.00 in the morning. A test meal was applied with 2 capsules pancreatin or placebo. Blood glucose and plasma levels of C-peptide, glucagon and pancreatic polypeptide (PP) were determined in regular intervals for 4 hours. Blood glucose levels were not significantly altered by pancreatin. As shown by M-value according to Schlichtkrull (21.6 +/- 2.9 versus 32.4 +/- 7.4), there was a tendency towards smaller oscillations of blood glucose with pancreatin treatment. C-peptide levels (basal 0.081 +/- 0.008 ng/ml; postprandial 0.119 +/- 0.013 ng/ml) were not significantly altered by the administration of pancreatin. Basal and postprandial glucagon and PP plasma levels were not influenced by pancreatin. From these results, we conclude that pancreatic enzyme supplementation does not significantly alter the requirement of insulin in patients with diabetes mellitus secondary to chronic pancreatitis. Possible disturbances of the enteroinsular axis are discussed in this paper. Topics: Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Glucagon; Humans; Insulin; Pancreatic Function Tests; Pancreatic Polypeptide; Pancreatin; Pancreatitis | 1990 |
[Experiences with conversion from MC-insulin NOVO to L-insulin S.N.C. of insulin dependent diabetic patients].
After a circa 10-year therapy with MC-insulin NOVO 12 diabetics were changed to the chromatographically purified insulins L-insulin S.N.C. and insulin S.N.C. of the nationally-owned enterprise Berlin-Chemie. 3 and 6 months, respectively, ago after the ambulatory change the patients were metabolically, immunologically, hormonally and clinically characterized. Profiles of blood glucose, value of glycaemia and HbA1 also lipid parameters, creatinine values, residual B-cell function, blood pressure and ophthalmologic state did not show any significant differences to the initial values after change to S.N.C.-insulins. Insulin-antibody level (9.5%-9.4%-9.7%) and insulin need (0.48 IU/kg-0.46 IU/kg-0.48 Iu/kg) also remained unchanged. Local reactions were not observed. Under the condition of a permanently good quality of the S.N.C.-insulins (purity and stability of the preparations) the application of chromatographically purified insulin of the firm Berlin-Chemie with comparable therapeutic success as in insulin MC NOVO is possible in a large part of the patients. Topics: Adult; Blood Glucose; C-Peptide; Delayed-Action Preparations; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Insulin, Regular, Pork; Male; Middle Aged | 1990 |
Prednisone administration in recent onset type I diabetes.
The aim of our study was to investigate the efficacy of prednisone to preserve pancreatic beta-cell function in patients with recent-onset Type I diabetes mellitus (IDDM). Twenty-five patients with IDDM, aged 24 +/- 6 years, entered the trial within 8 weeks of the onset of diabetes. They were allocated, according to a single blind randomized protocol, to one of the following treatments: (A) prednisone (15 mg/day), (B) indomethacin (100 mg/day), (C) placebo. All treatments lasted 8 months and all patients achieved satisfactory metabolic control with a multi-injection regimen (three injections/day) within a few weeks, and maintained it throughout the entire period of observation. Only minor side effects were observed in the prednisone-treated patients. A lower insulin requirement was observed in the prednisone group than in other patients at 12 months (0.33 +/- 0.11 vs 0.57 +/- 0.06 U/kg/day, P less than 0.05), 18 months (0.34 +/- 0.11 vs 0.64 +/- 0.06, P less than 0.05) and 24 months (0.38 +/- 0.10 vs 0.63 +/- 0.05, P less than 0.05). Endogenous insulin release, evaluated as urinary C-peptide, was higher in the prednisone group than in other patients at 3, 6, 9, 12, 18 and 24 months (P less than 0.05). ANOVA confirmed differences among the three groups. Our study indicates that prednisone administration, at low doses and for a long period of time, effectively restored endogenous insulin release in IDDM patients. Topics: Adolescent; Adult; Analysis of Variance; B-Lymphocytes; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; HLA-DR Antigens; Humans; Indomethacin; Insulin; Insulin Secretion; Islets of Langerhans; Longitudinal Studies; Male; Prednisone | 1990 |
The influence of high dose intravenous immunoglobulins on immunological and metabolic pattern in newly diagnosed type I diabetic patients.
In autoimmune disease the functional deficiency of T suppressor cells, also described in Type I diabetes, may be restored through immunoglobulin (Ig) infusion, which increases antigen phagocytosis, NK activity, cell clones and antibody anti-idiotype responses. Sixteen Type I diabetic patients were studied: eight were treated soon after the initial correction of disease-onset glycemic deterioration with intensive intravenous (i.v.) 7S Ig treatment (0.4 g/kg/BW) for 1 week and once per week for 6 months, whilst the remaining patients constituted the control group. All patients were evaluated during the study for metabolic and immunological parameters. A reduction in insulin requirement compared to conventionally treated patients was observed at the third (0.17 +/- 0.06 vs 0.44 +/- 0.08 IU/kg/BW; P less than 0.02) and at the sixth month of therapy (0.19 +/- 0.07 vs 0.54 +/- 0.07 IU/kg/BW; P less than 0.005). Two patients ceased to require insulin therapy within the BW; P less than 0.005). Two patients ceased to require insulin therapy within the first month, showing a prolonged restoration of B-cell function. Serum C-peptide values were also significantly higher in the Ig-treated group compared to the control group after 3 and 6 months. As regards immunological parameters, patients showed a decrease in insulin antibody levels and a reduction in TAC+ cells. Intravenous Ig therapy seems able to affect positively the first phases of metabolic and immunological deterioration of Type I diabetes. Topics: Adolescent; Adult; Autoantibodies; Autoimmune Diseases; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Immunization, Passive; Insulin; Male; Random Allocation; Receptors, Interleukin-2 | 1990 |
Early administration of an immunomodulator and induction of remission in insulin-dependent diabetes mellitus.
A clinical trial was undertaken to determine whether intensive thymopentin administration enhances remission of insulin-dependent diabetes (IDDM) during the first year after diagnosis. Dosage with insulin was minimized with target control of blood glucose levels less than or equal to 7.8 mmol/l before meals. Remission was defined as a prolonged period after IDDM onset (not less than 3 months) characterized by a non-insulin-receiving (NIR) state in which target metabolic control was reached without administration of insulin and with a valid C-peptide response, evaluated after standard breakfast. Sixteen IDDM patients aged 12-31 years, recruited within 2 weeks of initiation of insulin therapy and within 5 weeks of onset of symptoms, were treated with intravenous (i.v.) thymopoietin32-36 pentapeptide (Thy) (1 mg/kg/body weight) for 7 days and twice per week for up to 3 months. A control IDDM group without initial significant differences in metabolic control parameters was also studied. No difference was observed between the two IDDM groups regarding the after-diagnosis normalization curve of HbA1c; mean daily glycemic level rates and ICA titer decreased during the observation. A reduction in anti-insulin antibodies (AIA) in Thy-treated patients was observed in comparison to conventionally treated IDDM starting from 6 months and reaching a reduction peak at 1 year (P less than or equal to 0.02). As regards the NIR remission rate, it was significantly more accelerated in Thy-treated patients, reaching 43% at 6 months and 57% at 1 year vs 12% and 6.7% respectively in the control IDDM group (P range less than or equal to 0.05-0.02).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Hemoglobin A; Humans; Immunity, Cellular; Insulin; Receptors, Interleukin-2; Remission Induction; Thymopentin | 1990 |
Insulin requirements and residual beta-cell function 12 months after concluding immunotherapy in type I diabetic patients treated with combined azathioprine and thymostimulin administration for one year.
An increase in clinical and functional remissions with immunosuppression, as well as abnormal T-cell function, in Type I diabetic patients has been reported in the early stages of diabetes. A controlled trial with azathioprine and thymostimulin in separate and combined administration was performed in 45 recently diagnosed Type I diabetic patients. Phenotyping of the T-lymphocyte subsets, levels of CD25 positive cells and interleukin-2 production by patients' lymphocytes, as well as remission rate and stimulated C-peptide levels, were serially assessed. Remission was defined as mean weekly glycemic profiles less than or equal to 7 mmole/l, serial HbA1 values in the normal range and no insulin requirements for at least 2 consecutive months. At 3,6,9 and 12 months of immunotherapy, remission occurred respectively in 0%, 8.3%, 16.6% and 0% of the conventionally treated diabetic controls and in 42.8%, 50%, 42.8% and 36.2% of the subjects submitted to combined azathioprine and thymostimulin administration. Patients receiving azathioprine or thymostimulin alone did not achieve better remission rates than controls. C-peptide levels were significantly higher (above 0.6 pmol/ml) in patients with remission than in those not in remission (P less than 0.02) throughout the trial. Excessive interleukin-2 production in recently diagnosed diabetics returned to normal levels in patients in remission. In the group receiving combined therapy, 38.5%, 25% and 23% were still in clinical remission at 6, 9 and 12 months after drug withdrawal. Twelve months after stopping treatment, patients who had remitted exhibited significantly lower insulin requirements and greater endogenous insulin secretion than those who had not remitted; the former also maintained near normal glycemic control. No side effects were detected except mild and transient leucopenia in a reduced number of patients receiving azathioprine. Remission was related to the time of beginning immunotherapy after the onset of diabetes (17.1 +/- 7 vs 42.5 +/- 15 days; P less than 0.01) and to age (17.7 +/- 5.6 vs 13 +/- 7 years; P less than 0.05). Interleukin-2 production seems to be negatively associated with clinical remission in the early stages of diabetes. Results suggest a complementary effect of the drugs used in this study that may enhance long-term remission in recently diagnosed Type I diabetic patients. Topics: Adolescent; Adult; Azathioprine; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Humans; Immunophenotyping; Immunotherapy; Insulin; Interleukin-2; Islets of Langerhans; Lymphocyte Activation; Male; Receptors, Interleukin-2; T-Lymphocyte Subsets; Thymus Extracts | 1990 |
Adjunctive use of tolazamide in newly-diagnosed diabetic children.
Recent data suggests that one of the major actions of sulfonylureas is to potentiate the anabolic cellular effects of insulin. This is the first study to examine the use of sulfonylureas as adjunctive therapy in newly-diagnosed type I diabetic children. A random, prospective, double blind study over 15 months, stratified by age at diagnosis, was conducted. The treatment group (n = 13) received daily oral weight-adjusted tolazamide whereas the control group (n = 11) received placebo. Monthly comparison of the HbA1 values between groups revealed no statistical difference; likewise, the fasting serum C-peptide values were not dissimilar. The mean daily insulin dose per kilogram, however, was less in the tolazamide group (P less than 0.001). The data suggests that the addition of tolazamide may not be of therapeutic benefit in newly diagnosed juvenile diabetics, although insulin requirements may be reduced. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Female; Glycated Hemoglobin; Humans; Insulin; Male; Prospective Studies; Tolazamide | 1990 |
Proinsulin and C-peptide at onset and during 12 months cyclosporin treatment of type 1 (insulin-dependent) diabetes mellitus.
An increased proinsulin to C-peptide molar ratio at the onset of Type 1 (insulin-dependent) diabetes mellitus has been suggested. We studied fasting proinsulin levels and proinsulin/C-peptide ratios in the newly diagnosed diabetic subjects participating in the Canadian/European placebo controlled cyclosporin study at entry, during the one year treatment period and six months of follow-up. Available entry data from 176 out of the 188 allocated patients were compared to 60 age and weight matched control subjects. Fasting proinsulin was significantly elevated in male patients compared to male control subjects (p less than 0.01), whereas the levels only tended to be elevated in female patients. The proinsulin/C-peptide ratio was three to fourfold elevated in the diabetic groups of both sexes, (p less than 0.001). Further, proinsulin and C-peptide were studied in 83 cyclosporin and 86 placebo-treated subjects during the trial and follow-up. An additional increase of proinsulin/C-peptide ratio was observed during the first three months of placebo treatment. It remained constantly high for nine months and then declined to entry level. This pattern was not seen in the cyclosporin-treated group, where the ratio was unchanged during the 12 months trial and follow-up. The effect of cyclosporin on the induction of non-insulin requiring remission was unrelated to fasting and glucagon stimulated C-peptide levels at entry, whereas 64% of the cyclosporin-treated against 28% of the placebo-treated subjects (p less than 0.01) went into remission if the proinsulin/C-peptide ratio at entry was above 0.024.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Biomarkers; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Fasting; Female; Follow-Up Studies; HLA-DR Antigens; Humans; Male; Proinsulin; Reference Values | 1990 |
Cyclosporine A for the treatment of new-onset insulin-dependent diabetes mellitus.
It is not known whether early immunosuppressive treatment can preserve long-term endogenous insulin secretion in subjects with insulin-dependent diabetes mellitus. In the present study, clinical remissions during the first year and C-peptide production for 3 years were followed after 43 subjects with newly diagnosed insulin-dependent diabetes mellitus were randomly assigned to a cyclosporine A treatment group for 4 months or to a control group. Of the six cyclosporine A-treated subjects who had remissions, five were 19 years of age or younger, compared with two of the four in the control group. C-peptide production was present in 98% of all subjects after 4 months, in 88% after 1 year, and in 43% after 3 years. There were no significant differences in numbers of subjects with C-peptide production or in mean hemoglobin A1 levels, between cyclosporine A-treated and control subjects after 3 years. Cyclosporine A treatment of subjects with newly diagnosed insulin-dependent diabetes mellitus for a period of 4 months does not have the ability to preserve residual beta-cell function. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Cyclosporins; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Random Allocation | 1990 |
Glycemic index of foods in individual subjects.
We studied 12 subjects with diabetes to determine how well the glycemic index (GI) predicted the ranking of glycemic responses of different foods in individuals. All subjects ate three mixed meals (bread, rice, or spaghetti with GIs of 100, 79, and 61, respectively) four times in a randomized complete block design. The mean glycemic response areas of the different meals ranked according to the predicted GI in every individual. The observed mean +/- SD GI values of the meals were significantly different from each other (bread 100 +/- 7, rice 75 +/- 9, spaghetti 54 +/- 9), with no significant difference in response between subjects. It is concluded that individuals share common mean GI values for different foods. Within confidence limits determined by the variability of glycemic responses, the number of repeated tests conducted, and the expected GI difference, the GI can be used to predict the ranking of the mean glycemic responses of mixed meals taken by individuals. Topics: Adult; Aged; Blood Glucose; Bread; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dietary Carbohydrates; Energy Intake; Fasting; Female; Flour; Humans; Male; Middle Aged; Oryza; Random Allocation | 1990 |
Randomized prospective study of self-management training with newly diagnosed diabetic children.
This study was designed to evaluate the effects of a self-management training (SMT) program on metabolic control of children with insulin-dependent diabetes mellitus (IDDM) in the first 2 yr after diagnosis. After standard in-hospital diabetes education, 36 children (mean age 9.3 yr, range 3-16 yr) were randomized to conventional follow-up, conventional and supportive counseling (SC), or conventional and SMT, which emphasized use of data obtained from self-monitoring of blood glucose. SC and SMT interventions consisted of seven outpatient sessions with a medical social worker during the first 4 mo after diagnosis and booster sessions at 6 and 12 mo postdiagnosis. Groups were similar with respect to age, sex, body mass index, socioeconomic status, C-peptide, and severity of illness at diagnosis. Metabolic control, measured quarterly by glycosylated hemoglobin (HbA1), improved substantially in all three treatment groups during the first 6 mo. SMT patients had significantly lower HbA1 levels than conventional patients at 1 yr (P less than 0.01) and 2 yr (P less than 0.05) postdiagnosis. SMT patients also had lower HbA1 levels than SC patients, but this did not reach statistical significance. The lower HbA1 levels of SMT patients were not explained by severity of illness at diagnosis, or insulin dose, body mass index, and C-peptide levels at 2 yr. These results suggest that an SMT program during the first few months after diagnosis helps avoid the deterioration in metabolic control often seen in children with IDDM between 6 and 24 mo after diagnosis. Topics: Adolescent; Bicarbonates; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Male; Patient Discharge; Patient Education as Topic; Prospective Studies; Random Allocation; Self Care; Socioeconomic Factors | 1990 |
Human islet transplantation in patients with type I diabetes.
Topics: Blood Glucose; C-Peptide; Cell Separation; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Graft Rejection; Humans; Islets of Langerhans Transplantation | 1989 |
Efficacy of bedtime NPH insulin with daytime sulfonylurea for subpopulation of type II diabetic subjects.
Although insulin and sulfonylureas often have additive clinical effects when used in combination for type II (non-insulin-dependent) diabetes, these results are variable and a clinical role for this approach is not yet established. This study tests the efficacy of a specific combined regimen for a subpopulation of patients with a randomized double-masked placebo-controlled crossover design and under conditions similar to those of clinical practice. Twenty subjects with limited duration (less than 15 yr) type II diabetes who were moderately obese (less than 160% ideal wt) and proved imperfectly controlled on 10 mg glyburide twice daily completed two 4-mo crossover protocols, comparing a single injection of NPH insulin in the evening plus 10 mg glyburide in the morning with insulin plus placebo. Insulin dose was adjusted by experienced endocrinologists seeking the best glycemic control consistent with safety. All subjects had glycosylated hemoglobin values less than or equal to 150% of the control mean on combined therapy, and combined therapy was superior to insulin alone (fasting plasma glucose 8.0 +/- 0.3 vs. 11.1 +/- 0.6 mM, P less than .01; glycosylated hemoglobin 9.8 +/- 0.1 vs. 10.6 +/- 0.2%, P less than .01). Despite greater weight gain on combined therapy, blood pressure and plasma lipid concentrations were the same on the two regimens. These results suggest this simple regimen offers another option, besides multiple injections of insulin, for patients of this kind who are unsuccessful with a sulfonylurea or a single injection of insulin alone. Topics: Adult; Aged; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Administration Schedule; Drug Therapy, Combination; Eating; Fasting; Glucagon; Glyburide; Humans; Insulin, Isophane; Middle Aged; Random Allocation | 1989 |
Effect of nicotinamide therapy upon B-cell function in newly diagnosed type 1 (insulin-dependent) diabetic patients.
This study describes the effects of nicotinamide therapy on B-cell function in Type 1 (insulin-dependent) diabetes. C-peptide secretion was studied in 20 patients newly diagnosed with Type 1 diabetes at basal state and also after an i.v. glucagon stimulus. Patients were randomly allocated according to a single-blind schedule, to one of the following treatments over a 45-day period: Group 1: 10 patients, nicotinamide 1 g/day; Group 2: 10 patients, placebo. The C-peptide secretion tests were performed before treatment and on days 15, 45, 180, 365 of the follow-up. The clinical and metabolic data were similar in the two groups of patients. Basal and stimulated C-peptide levels increased by 45 days in both groups, but the increase in stimulated C-peptide response was greater in the nicotinamide group (p less than 0.01). However, the B-cell function decreased after the period of nicotinamide administration. No difference in the number of clinical remissions or insulin requirement and HbA1 between the groups was observed. These data suggest that treatment of Type 1 diabetes with nicotinamide at diagnosis is associated with a moderate increase of C-peptide secretion recovery. Topics: Adolescent; Autoantibodies; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Niacinamide | 1989 |
Effect of nicotinamide treatment on the residual insulin secretion in type 1 (insulin-dependent) diabetic patients.
In vivo and in vitro experiments have shown that nicotinamide enhances the regeneration of rat B cells. Nicotinamide has been administered to human subjects at a dose of 3 g/day for more than one year without any serious side effects. A trial was conducted to study if nicotinamide could protect B cells in Type I (insulin-dependent) diabetic patients with established diabetes, but still with residual insulin secretion, the latter being evaluated throughout the study period. A randomized double-blind study was carried out on 26 Type I diabetic patients aged 15 to 40 years who had been treated with insulin for 1 to 5 years but who had a residual insulin secretion characterized by a glucagon stimulated C-peptide level higher than 0.1 nmol/l. They were given either 3 g/day of nicotinamide or a placebo for nine months. At baseline the treated and control groups did not differ according to age, diabetes duration, insulin dose, HbA1c or C-peptide levels. Three patients dropped out of the study. At 9 months there were no significant changes in the insulin doses required. However, HbA1c rose in the control group (8.1 +/- 0.4 vs 9.8 +/- 0.5%, p less than 0.05) but not in the nicotinamide treated group (7.5 +/- 0.5 vs 6.9 +/- 0.4%).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; HLA-DR Antigens; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Niacinamide | 1989 |
A comparison of human ultralente- and lente-based twice-daily injection regimens.
The problem of fasting hyperglycaemia remains unresolved on currently used twice-daily injection regimens. Human ultralente insulin is of longer duration than human lente and differs from it only in the nature of the zinc-insulin complex. In a 6-month double-blind crossover study these insulins were compared in 66 patients who were randomized to human ultralente or human lente insulin given together with human soluble insulin in a twice-daily injection regimen. Patients were seen monthly and crossed over after 3 months treatment. Fasting blood glucose concentrations on the ultralente regimen were considerably lower than on the lente regimen, the difference being statistically significant (6.6 +/- 0.5 vs 8.2 +/- 0.5 mmol l-1, p less than 0.05), but only present in those patients with fasting concentrations below the median. Glycosylated haemoglobin was identical on both regimens (9.3 +/- 0.2%). The evening ultralente dose was slightly but significantly lower than the evening lente dose (14.9 +/- 0.8 vs 15.5 +/- 0.8 U, p less than 0.05) thus endorsing the lowering effect of ultralente on the fasting blood glucose concentration. However, the incidence of serious hypoglycaemic events was higher on the ultralente regimen (0.38 +/- 0.10 vs 0.09 +/- 0.04 events per patient-month, p less than 0.02), the majority of nocturnal events occurring between 0500 h and breakfast. We conclude that ultralente insulin can give an improved fasting blood glucose concentration but that in those patients with more marked fasting hyperglycaemia or with a nocturnal hypoglycaemia problem it offers no clinical advantage over human lente insulin in a twice-daily injection regimen. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Delayed-Action Preparations; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Injections, Subcutaneous; Insulin, Long-Acting; Male; Middle Aged; Recombinant Proteins | 1989 |
Continuous subcutaneous insulin infusion (CSII) versus conventional injection therapy in newly diagnosed diabetic children: two-year follow-up of a randomized, prospective trial.
The effect of continuous subcutaneous insulin infusion (CSII), begun at diagnosis, on blood glucose control and endogenous insulin production was studied in a group of consecutively referred newly diagnosed diabetic children. In a random order, 15 children started CSII (age 9.5 +/- 4.2 (+/- SD) years) and 15 conventional injection therapy (age 7.0 +/- 3.6 years). For 2 years HbA1 and urinary C-peptide were measured monthly, C-peptide responses to glucagon 6-monthly, and insulin antibodies every 3 months. None of the patients requested change of therapy during the study period, but at 28 months 1 adolescent girl changed to injection therapy from CSII. Severe hypoglycaemia was observed once in each group, but ketoacidosis only once, in the injection therapy group. From 2 months after diagnosis onwards the CSII group had significantly lower HbA1 levels. Urinary and plasma C-peptide levels did not differ between the two groups and similar insulin doses were used throughout the study. At the end of the 2 years of therapy, the CSII group had significantly lower insulin antibody levels. The observations suggest that CSII is well accepted in newly diagnosed children and improves metabolic control, but does not prolong endogenous insulin production. Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Insulin Infusion Systems; Male; Prospective Studies; Randomized Controlled Trials as Topic; Reference Values | 1989 |
Comparison of the safety and effectiveness of human and bovine long-acting insulins.
Since ultralente insulin pharmacokinetics suggest faster absorption by human insulin when compared with bovine insulin using the subcutaneous route, the safety and efficacy of human ultralente in the outpatient setting was evaluated. Twenty type I patients participated in a randomized study using a crossover design of four six-week phases: (a) one daily injection of human ultralente; (b) two daily injections of human ultralente; (c) one daily injection of bovine ultralente and (d) two daily injections of bovine ultralente. Pre-meal human regular insulin was used with ultralente insulins and comprised 39 +/- 2% of the total daily insulin dose. Total and ultralente daily insulin doses were lower with human ultralente insulin (51.3 +/- 3.0 total and 30.9 +/- 3.4 ultra lente u/day) when compared to bovine ultralente insulin (57.8 +/- 4.4 and 36.1 +/- 4.4 u/day, p less than 0.01), yet the metabolic control achieved was virtually identical during both phases: (hemoglobin Alc 8.6 +/- 0.2% human vs. 8.4 +/- 0.4 bovine, p = NS). The frequency of mild hypoglycemia was 3.0 +/- 0.5 events per week vs 2.0 +/- 0.3 (p = NS). No severe hypoglycemia occurred. There were no differences between blood glucose daily profiles, insulin doses, hemoglobin Alc (8.6 +/- 0.4% BID vs. 8.4 +/- 0.3% QD injections) and occurrence of hypoglycemia between the single and two-dose long-acting regimens. These data indicate that long-acting semi-synthetic human insulin (a) can be effectively used as a once daily injection, (b) may be more biologically active than bovine, and (c) can be associated with safe and effective diabetes control. Topics: Adult; Animals; C-Peptide; Cattle; Delayed-Action Preparations; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin, Long-Acting; Male; Recombinant Proteins | 1989 |
A randomized trial of intensive insulin therapy in newly diagnosed insulin-dependent diabetes mellitus.
A period of early, intensive insulin treatment is thought to improve subsequent beta-cell function in insulin-dependent diabetes mellitus (IDDM). To study this hypothesis, we randomly assigned adolescents with newly diagnosed IDDM to receive either conventional treatment (n = 14) (NPH insulin, 1 U per kilogram of body weight per day, in two divided doses) or an experimental treatment (n = 12) (a two-week hospitalization with maintenance of blood glucose levels between 3.3 and 4.4 mmol per liter by continuous insulin infusion delivered by an external artificial pancreas [Biostator]). During the two-week intervention, the experimental-therapy group received four times more insulin than the conventionally treated group, and their endogenous insulin secretion was more completely suppressed, as evidenced by a urinary C-peptide excretion rate one seventh that of the conventionally treated group. After the first two weeks, both groups were treated similarly and received similar amounts of insulin. At one year, the mean (+/- SEM) plasma level of C peptide was significantly higher after mixed-meal stimulation in the experimental-therapy group than in the conventionally treated group (0.51 +/- 0.07 vs. 0.27 +/- 0.06; P less than 0.01). The experimental-therapy group also had better metabolic control, as evidenced by lower glycohemoglobin values (7.2 +/- 0.7 vs. 10.8 +/- 1.2 percent; P less than 0.01). We conclude that suppression of endogenous insulin by intensive, continuous insulin treatment during the first two weeks after the diagnosis of IDDM may improve beta-cell function during the subsequent year. Topics: Adolescent; C-Peptide; Depression, Chemical; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Islets of Langerhans; Male; Random Allocation | 1989 |
Double-blind controlled trial of azathioprine in children with newly diagnosed type I diabetes.
A double-blind controlled trial of azathioprine (2 mg.kg-1.day-1) was conducted with 49 patients aged 2-20 yr (mean 10.8 yr) who had newly diagnosed type I (insulin-dependent) diabetes. Patients were randomly assigned to receive either azathioprine (n = 24) or placebo (n = 25) for 12 mo, beginning within the 20-day period after diagnosis. Baseline clinical and metabolic characteristics did not differ between the two groups. No patient experienced complete remission, defined as restoration of normal carbohydrate tolerance without other treatment. Partial remission, defined as good metabolic control (hemoglobin A1c less than or equal to 7.9%, preprandial blood glucose less than or equal to 8 mM with an insulin dose of less than 0.5 U.kg-1.day-1), occurred in 10 placebo (40%) and 7 azathioprine (29%) patients at 6 mo and in 4 placebo (16%) and 4 azathioprine (17%) patients at 12 mo (differences not significant). Fasting plasma C-peptide was significantly greater in the azathioprine-treated group at 3 and 6 mo, but this difference was not sustained. C-peptide responses to a standard meal and the frequency of islet cell and insulin antibodies did not differ between the two groups over the 12-mo period. Azathioprine caused no significant side effects. We conclude that in the dosage used, and despite early effects on endogenous insulin secretion, azathioprine alone does not influence the remission phase in children with newly diagnosed type I diabetes. Topics: Azathioprine; Blood Glucose; C-Peptide; Child; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Male | 1989 |
Effect of cyclosporin A on B-cell loss in type 1 (insulin-dependent) diabetes mellitus.
Topics: Adult; C-Peptide; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Fasting; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans | 1989 |
Cyclosporin-induced remission of IDDM after early intervention. Association of 1 yr of cyclosporin treatment with enhanced insulin secretion. The Canadian-European Randomized Control Trial Group.
A randomized double-blind placebo-controlled trial was undertaken to determine whether cyclosporin enhances remission of insulin-dependent diabetes mellitus (IDDM) through the 1st yr after diagnosis. Dosage with insulin was minimized with target control of blood glucose levels less than or equal to 7.8 mM (140 mg/dl) before meals. Metabolic control was evaluated by serial determinations of glycosylated hemoglobin levels, and endogenous secretion of insulin was evaluated by determination of the levels of glucagon-stimulated insulin-connecting peptide (CP) in the plasma at 3-mo intervals. A compound definition of remission required a glucagon-stimulated CP level in plasma greater than or equal to 0.6 nM or a non-insulin-receiving state (NIR) in which target control of glycemia was maintained without administration of insulin. A clinical definition of remission required only the NIR state as defined. One hundred eighty-eight patients aged 10-35 yr entered the study within 6 wk of initiation of insulin therapy and within 14 wk of onset of symptoms and were studied for 1 yr. There were no significant differences in metabolic control between the two treatment groups during the study. The anticipated adverse effects of cyclosporin were not more frequent or severe than in other experience with the drug, but histological changes attributable to cyclosporin were present in some kidney biopsies obtained from selected patients after 1 yr. At 1 yr, by the compound definition, 33% of the cyclosporin-group and 21% of the placebo-group patients were in remission, when the corresponding rates for NIR remissions were 24 and 10%.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; Blood Pressure; C-Peptide; Child; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Male; Random Allocation; Regression Analysis | 1988 |
Improved metabolic control in insulin-dependent diabetes mellitus with insulin and tolazamide.
The influence of sulfonylurea drugs in enhancing the effect of endogenous insulin is well documented. Furthermore, combination therapy with sulfonylurea and insulin is effective in the treatment of type II diabetes mellitus. Therefore, to assess the efficacy of this type of combination therapy in type I diabetes, we conducted a double-blind clinical trial with tolazamide and insulin in 15 subjects with type I diabetes. The diagnosis of type I diabetes was confirmed by previous episodes of diabetic ketoacidosis and undetectable C-peptide levels in serum samples from blood drawn from patients two hours after breakfast. During the study protocol, placebo or tolazamide was randomly added to insulin and the combination therapy was continued for three months. In the placebo group, levels of fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) did not alter significantly at the end of the study period. However, in the tolazamide group, levels of FPG and HbA1c markedly improved after administration of tolazamide (FPG levels before therapy, 10.8 +/- 0.9 mmol/L [mean +/- SEM]; after therapy, 6.7 +/- 0.4 mmol/L; HbA1c levels before therapy, 10.9% +/- 0.6%; after therapy, 9.6% +/- 0.5%). Therefore, adjuvant therapy with tolazamide and insulin may be beneficial in achieving adequate metabolic control in type I diabetes mellitus. Topics: Adult; Aged; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Glycated Hemoglobin; Glycosuria; Humans; Insulin; Middle Aged; Random Allocation; Tolazamide | 1988 |
Metabolic effects of continuous subcutaneous insulin infusion: evidence that a rise and fall of portal vein insulin concentration with each major meal facilitates post-absorptive glycemic control.
Eighteen lean adult volunteers with insulin-requiring diabetes mellitus attempted to achieve normoglycemia using continuous subcutaneous insulin infusion (CSII) or conventional insulin therapy (CIT) in a randomized crossover trial of 68 +/- 2.5 weeks (mean +/- SEM) duration. As reported (Diabetes Care 8: 447-55, 1985) the group with absent to low beta-cell function (C-peptide negative, n = 11) attained mean post-absorptive normoglycemia only during CSII vs CIT (p less than 0.05). Only following CSII was this without change in post-absorptive serum triglyceride concentrations (-4 +/- 5.6 vs 12 +/- 4.7 mg/dl; -0.04 +/- 0.6 vs 0.14 +/- 0.05 mM, p less than 0.05) or body weight (0.01 +/- 0.02 vs 0.05 +/- 0.01 kg/week, p less than 0.05). In the group with glucagon stimulated serum C-peptide 100-400 pmol/L (C-peptide positive) responses to CSII or CIT were equal. As total daily insulin dosage (0.05 +/- 0.04 U/kg/day) was the same under all conditions, to explain the efficacy of CSII, glucoregulatory hormone responses were examined. Pre- and post-test breakfast serum free immunoreactive insulin and plasma glucagon concentrations were essentially unaffected by C-peptide or treatment status. Erythrocyte 125I-insulin binding was decreased in the C-peptide negative group only during CSII (8.6 +/- 0.5 vs 10.1 +/- 0.7%, p less than 0.005); C-peptide positive group receptor binding was consistently low (8.2 +/- 0.8, 8.4 +/- 0.9%). During CIT using intermediate-acting insulin post-lunch peripheral venous insulin failed to rise (p less than 0.05), but in the C-peptide positive group, on the basis of C-peptide responses to breakfast an undetected rise and fall of portal venous insulin was assumed to coincide with each meal. Thus, only during CIT in the C-peptide negative group, which received on average 6.4/wk/subject fewer pre-meal regular insulin boluses (p less than 0.01), was the frequency of meal-related change in portal insulinemia decreased. Consistent meal-related fluctuations in portal insulinemia inherent in CSII hepatocytes sensitized by a post-receptor mechanism to the suppressive effects of insulin on glucose output and thus were indirectly responsible for the observed improvement in glycemic control and lipid metabolism in the C-peptide negative group. Topics: Adult; Body Composition; C-Peptide; Cholesterol; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Eating; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Middle Aged; Random Allocation; Triglycerides | 1988 |
Immunosuppression with azathioprine and prednisone in recent-onset insulin-dependent diabetes mellitus.
We randomly assigned 46 patients (mean age, 11.7 years; range, 4.5 to 32.8) with newly diagnosed insulin-dependent diabetes mellitus within two weeks of beginning insulin to receive either corticosteroids for 10 weeks plus daily azathioprine for one year or no immunosuppressive therapy. Half the 20 immunosuppressed patients completing the one-year trial had satisfactory metabolic outcomes (hemoglobin A1c less than 6.8 percent; stimulated peak C peptide greater than 0.5 nmol per liter; insulin dose less than 0.4 U per kilogram of body weight per day) as compared with only 15 percent of the controls. Three of 20 immunosuppressed patients, but no controls, were insulin independent at one year. Two of these continue to receive azathioprine without insulin after more than 27 months of follow-up. The response to immunosuppression correlated with older age, better initial metabolic status, and lymphopenia (less than 1800 lymphocytes per cubic millimeter) resulting from immunosuppression. The side effects of azathioprine included vomiting in one patient and mild hair loss in several others. Prednisone use resulted in a transient cushingoid appearance, weight gain, and hyperglycemia. The growth rate remained normal in all patients. We conclude that early immunosuppression with short-term use of corticosteroids plus daily azathioprine can improve metabolic control in some patients with insulin-dependent diabetes mellitus, but results from this unblinded study are preliminary and require further confirmation and long-term follow-up. Topics: Adolescent; Adult; Autoantibodies; Azathioprine; C-Peptide; Child; Child, Preschool; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Hemoglobin A; Humans; Immunosuppressive Agents; Islets of Langerhans; Male; Prednisone; Random Allocation; Time Factors | 1988 |
Long-term correction of hyperglycemia and progression of retinopathy in insulin dependent diabetes. A five-year randomized prospective study.
Thirty-eight patients with insulin dependent diabetes mellitus who had background retinopathy and no residual endogenous insulin secretion as assessed by plasma C-peptide determinations, were randomized to either conventional insulin treatment or to more intensive glucose control using ultralente insulin as basal cover and soluble insulin at mealtimes and were followed for five years. Plasma glucose profile and glycosylated hemoglobin were determined every eight weeks. Eye examinations were performed at the start of the study and after one, three and five years. Age, duration of diabetes, insulin dosage, glycemic control were comparable in the two groups. The mean plasma glucose profile was similar at entry in both groups and did not change in the conventionally-treated group. Mean plasma glucose profile 11.2 +/- 1 mmol/l with glycosylated hemoglobin level 10.7 +/- 0.3% fell to 7.9 +/- 0.4 mmol/l and 8.7 +/- 0.5% respectively during intensive treatment. Retinal morphology deteriorated during the follow-up with no significant differences between patients under unchanged conventional treatment and intensive insulin regimen. Proliferative retinopathy developed in six patients--three of these were under intensive insulin treatment. These data suggest that substantial long-term improvement of glycemic control does not affect progression of background retinopathy even when it is mild. The evolution of established retinopathy in insulin dependent diabetic patients is not only a function of poor glycemic control; other factors, either intrinsic or environmental, must also be important. Topics: Adult; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Hyperglycemia; Insulin; Insulin, Long-Acting; Male; Middle Aged; Prospective Studies; Random Allocation | 1988 |
Development of insulin antibodies, metabolic control and B-cell function in newly diagnosed insulin dependent diabetic children treated with monocomponent human insulin or monocomponent porcine insulin.
One hundred and thirty eight patients participated in a two-year randomized, double-blind multicentre trial to compare monocomponent human insulin and porcine insulin in the treatment of newly diagnosed insulin dependent diabetic children with respect to development of insulin antibodies, metabolic control and B-cell function. There was no difference between the two patient groups throughout treatment either in the level of IgG insulin binding or the percentage of patients with insulin antibodies (IgG-insulin greater than 0.012 U/l). However, the estimated mean of log insulin binding values in the antibody positive patients alone was significantly lower (p less than 0.05) in the human insulin treated group at all times apart from 1 and 18 months (e.g., human insulin group at one and two years: 0.104 and 0.152 U/l, porcine insulin group at one and two years: 0.162 and 0.212 U/l). The insulin antibodies in both patient groups bound equivalent amounts of human and porcine insulin tracer. Metabolic control, insulin dosage and B-cell function in the two treatment groups were similar throughout the treatment period. It is concluded that in newly diagnosed insulin dependent diabetic children monocomponent human insulin is slightly less immunogenic than monocomponent porcine insulin, and equally effective in overall metabolic control. Topics: Animals; Blood Glucose; C-Peptide; Child; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Immunoglobulin G; Insulin; Insulin Antibodies; Islets of Langerhans; Multicenter Studies as Topic; Random Allocation; Recombinant Proteins; Swine | 1988 |
Pulsatile insulin delivery is more efficient than continuous infusion in modulating islet cell function in normal subjects and patients with type 1 diabetes.
The respective modulating effects of continuous and intermittent insulin delivery on pancreatic islet cell function were studied in seven normal men and nine insulin-dependent (type 1) diabetic patients. In the normal men, saline or continuous (0.8 mU kg-1 min-1) or pulsatile (5.2 mU kg-1 min-1, with a switching on/off length of 2/11 min) human insulin were delivered on different days and in random order. Despite hyperinsulinemia, blood glucose was kept close to its basal value by the glucose clamp technique. The diabetic patients also were infused in random order and on different days with either saline or a smaller amount of insulin delivered continuously (0.15 mU kg-1 min-1) or in a pulsatile manner (0.97 mU kg-1 min-1 for 2 min, followed by 11 min during which no insulin was infused). In all experiments, 5 g arginine were given iv as a bolus dose 30 min before the end of the study, and plasma C-peptide and glucagon levels were determined to assess islet cell function. In the normal men, insulin administration resulted in a significant decline of basal plasma glucagon and C-peptide levels and in a clear-cut decrease in the arginine-induced glucagon response. These effects of insulin were significantly more marked when insulin was delivered in a pulsatile rather than a continuous manner. In the insulin-dependent diabetic patients, the lower dose of insulin infused continuously did not alter the basal or arginine-stimulated glucagon response. In contrast, when the same amount of insulin was delivered intermittently, arginine-induced glucagon release was greatly reduced. Thus, these data support the concept that insulin per se is a potent physiological modulator of islet A- and B-cell function. Furthermore, they suggest that these effects of insulin are reinforced when the hormone is administered in an intermittent manner in an attempt to reproduce the pulsatile physiological release of insulin. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Insulin Infusion Systems; Islets of Langerhans; Male; Pulsatile Flow; Reference Values | 1988 |
Cyclosporine trials in diabetes: updated results of the French experience.
Topics: Autoimmune Diseases; Azathioprine; C-Peptide; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Humans; Insulin; Prednisone; Recurrence | 1988 |
Effects of immunosuppression with cyclosporine in insulin-dependent diabetes mellitus of recent onset: the Canadian open study at 44 months.
Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Humans; Insulin; Pilot Projects | 1988 |
Effects of age, duration and treatment of insulin-dependent diabetes mellitus on residual beta-cell function: observations during eligibility testing for the Diabetes Control and Complications Trial (DCCT). The DCCT Research Group.
To examine the effects of age and duration and treatment of insulin-dependent diabetes (IDDM) on residual beta-cell function, we measured the fasting and Sustacal-stimulated serum C-peptide levels in 610 conventionally treated IDDM patients (age, 13-39 yr; duration of diabetes, 1-15 yr) during eligibility screening for the Diabetes Control and Complications Trial (DCCT). Fasting and stimulated C-peptide values were closely correlated (r = 0.83; P less than 0.001), and both declined with increasing duration of disease. However, among patients who had been diabetic for more than 5 yr, 11% (33 of 296) of adults compared with 0 of 75 adolescents (P less than 0.001) retained substantial insulin secretory capacity. Patients with stimulated C-peptide levels greater than 0.2 pmol/mL had a significantly lower mean fasting plasma glucose level [177 +/- 6 (+/- SEM) vs. 222 +/- 6 mg/dL; P less than 0.001), a smaller rise in glucose after Sustacal administration (151 +/- 5 vs. 184 +/- 3 mg/dL; P less than 0.001), and lower hemoglobin A1C (8.4 +/- 0.2% vs. 9.3 +/- 0.1%; P less than 0.001) than the patients with a stimulated C-peptide level of 0.05 pmol/mL or less, even though the C-peptide secretors were receiving less insulin (0.52 +/- 0.02 vs. 0.78 +/- 0.02 U/kg X day; P less than 0.001). To determine the effects of treatment of beta-cell function, 33 patients with stimulated C-peptide values between 0.2 and 0.5 pmol/mL at entry in the DCCT were restudied 1 yr after randomization to standard treatment (n = 15) or an experimental (n = 18) treatment designed to achieve and maintain near-normal glucose levels. Although C-peptide levels declined in both groups, experimental treatment was associated with slightly less of a decline in stimulated C-peptide values compared to Standard treatment. The results of C-peptide measurements in this large and well defined population of IDDM patients demonstrate that residual beta-cell function continues for a longer period of time in adults compared to adolescents with IDDM. This endogenous insulin secretion contributes significantly to metabolic control and may be prolonged by intensive insulin treatment regimens. Topics: Adolescent; Adult; Aging; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Time Factors | 1987 |
Effect of porcine gastric inhibitory polypeptide on beta-cell function in type I and type II diabetes mellitus.
The effect of highly purified natural porcine GIP on C-peptide release was examined in six type I (insulin-dependent) diabetics (IDD) with residual beta-cell function, six type II non-insulin-dependent) diabetics (NIDD), and six normal subjects. All subjects were normal weight. From -120 minutes to 180 minutes glucose or insulin was infused IV to achieve a constant plasma glucose level of 8 mmol/L. On two separate days GIP (2 pmol/kg/min) or isotonic NaCl at random were infused from 0 to 30 minutes. After 10 minutes of GIP infusion plasma IR-GIP concentrations were in the physiologic postprandial range. At 30 minutes a further increase in IR-GIP to supraphysiologic levels occurred. In all subjects plasma, C-peptide increased more after 10 minutes of GIP infusion (IDD, 0.48 +/- 0.05; NIDD, 0.79 +/- 0.11; normal subjects, 2.27 +/- 0.29 nmol/L) than on the corresponding day with NaCl infusion (IDD, 0.35 +/- 0.03; NIDD, 0.62 +/- 0.08; normal subjects, 1.22 +/- 0.13 nmol/L, P less than .05 for all). The responses of the diabetics were significantly lower than that of the normal subjects (P less than .001 for both groups). No further increase in C-peptide occurred during the remaining 20 minutes of the GIP infusion in the diabetic subjects (IDD, 0.49 +/- 0.05; NIDD, 0.83 +/- 0.10 nmol/L). In the presence of a plasma glucose concentration of 8 mmol/L, physiologic concentrations of porcine GIP caused an immediate but impaired beta-cell response in IDD and NIDD patients. Topics: Adult; Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gastric Inhibitory Polypeptide; Humans; Insulin; Islets of Langerhans; Male; Middle Aged; Swine | 1987 |
Buffy coat transfusions in early type I diabetes.
Fresh whole-blood buffy coats from American Red Cross volunteers were used to treat early type I diabetes. Attempts were made to adapt to human diabetic patients a protocol successfully used in prediabetic BB rats. Twenty-two type I diabetic patients (duration of disease less than 4 wk) were randomized to treatment or control groups; the treatment patients were given one buffy coat (approximately 0.6 X 10(9) T-lymphocytes) weekly for 5 wk. Plasma C-peptide (stimulated and unstimulated), insulin dose, and hemoglobin A1c were measured before and periodically after the treatment for 24 wk. The control group underwent the same studies. Although there were no significant differences for the parameters studied between the two groups, 2 of 12 patients in the treatment group underwent three complete (normal glycemia without insulin) temporary remissions. One of these patients was given a second course of transfusions after relapse from the first remission and developed a second complete remission that lasted 2 mo. No control patient had remissions during the 24-wk study. Although the future of adoptive immunotherapy in the treatment or prevention of diabetes is not known, several probable limitations of the current protocol, as discussed here, can explain the differences in results between this trial and the rodent studies. Topics: Adolescent; Adult; Antigens, Differentiation, T-Lymphocyte; Autoantibodies; Blood Transfusion; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Immunization, Passive; Islets of Langerhans; Male; T-Lymphocytes | 1987 |
Kinetics of human and porcine insulins in normal and type I diabetic subjects.
Human and porcine insulin were infused intravenously at various rates into 4 normal and 6 Type I diabetic subjects, using a double-blind cross-over design and a euglycaemic glucose clamp, to study the relationship between the steady state plasma free insulin concentration and its plasma disappearance rate. By mathematical model validation procedures both human and porcine insulin were found to obey saturation kinetics in normal subjects and first order kinetics in diabetic subjects in the insulin concentration range studied (0-2 nmol/l). No differences in parameters were observed between the two types of insulin in the study groups. The median clearance rate of insulin in normal subjects was 31 ml.kg-1.min-1 at infinitesinal plasma insulin concentrations versus 21 ml.kg-1.min-1 in the diabetic subjects. Thus, at physiological plasma concentrations both human and porcine insulin disappear faster via the saturable mechanism(s) found in normal subjects than via the apparently linear mechanism(s) found in diabetic subjects. Topics: Adult; Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Male; Models, Biological; Species Specificity; Swine | 1987 |
Sustained normoglycemia and remission phase in newly diagnosed type I diabetic subjects. Comparison between continuous subcutaneous insulin infusion and conventional therapy during a one year follow-up.
After onset of type I diabetes 7 diabetics were randomized to subcutaneous insulin pump treatment (CSII) (age 12 to 29 years, mean: 21 years) and 7 diabetics to conventional insulin treatment (CI) (age 14 to 28 years, mean: 21 years). HbA1, glycosylated serum proteins and mean blood glucose (MBG) as parameters of metabolic control were determined monthly. After 2 months both groups showed HbA1 values in the normal range. Mean MBG values were (mean +/- SD) 116 +/- 7 mg/dl for CSII and 118 +/- 14 mg/dl for CI. Residual insulin secretion was determined monthly by fasting C-peptide. After 14 days, 5, 7, 8 months fasting C-peptide values were significantly (P less than 0.05) higher in CI. After one year fasting C-peptide was comparable in both groups (CSII and CI mean: 0.06 nmol/l). The administered insulin dose was comparable in both groups with a 55% reduction of insulin dose after 5 months in CSII (0.35 +/- 0.15 U/kg/24 h) and in CI after 7 months (0.31 +/- 0.28 U/kg/24 h). After 12 months of insulin therapy about 60% of the initial insulin dose was injected in both groups. 1 patient on CSII (12 years) and 2 patients on CI (15, 28 years) showed a complete remission (for 3-9 months) with no exogenous insulin and normal HbA1 values. 50% of the patients had episodes where they did need less than 0.2 U/kg/24 h insulin to maintain optimal diabetic control (3 CSII, 4 CI). During the first year of insulin treatment in type I diabetes with CSII as well as with CI a comparable near normalisation of diabetic control could be achieved. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Male; Remission Induction | 1987 |
Effect of high doses intravenous IgG in newly diagnosed diabetic children.
A controlled trial was carried out on type I diabetic children in order to evaluate the clinical effect of high doses intravenous gammaglobulins (i.v. IgG). Twenty newly diagnosed patients were admitted to the trial, ten of whom received 400 mg/kg body weight of i.v. IgG on 5 consecutive alternate days and subsequently after 15 days and monthly thereafter for up to six months, while ten patients served as controls. Insulin requirement in the treated and untreated groups was essentially similar at the start of the trial (0.94 +/- 0.47 vs 1.11 +/- 0.28) but showed a statistically significant difference at 3 (0.40 +/- 0.28 vs 0.66 +/- 0.26), 6 (0.36 +/- 0.19 vs 0.63 +/- 0.27) and 9 (0.38 +/- 0.20 vs 0.62 +/- 0.25) months. The difference was still evident at 12 months but no longer reached statistical significance. The reduced requirement of insulin was accompanied by a parallel increase in the C-peptide serum levels. Lymphocyte subpopulations, C3 and C4 and immune-complex levels did not show any significant modification after i.v. IgG administration. Topics: Adolescent; Antigen-Antibody Complex; Blood Glucose; C-Peptide; Child; Child, Preschool; Complement C3; Complement C4; Diabetes Mellitus, Type 1; Drug Evaluation; Female; Glycated Hemoglobin; Humans; Immunoglobulin G; Infusions, Intravenous; Insulin; Lymphocytes; Male; Time Factors | 1987 |
Comparison of blood glucose profile and glycemic control in type 1 diabetic patients treated with Actrapid-Monotard or Actrapid Protaphane (NPH) human insulins.
The aim of this study is to compare the blood glucose profile and the glycemic control in Type 1 diabetic patients under two conventional semi-synthetic human insulin regimens (2 daily injections) combining regular (Actrapid) and intermediate acting insulins (Monotard or Protaphane). Actrapid-Monotard (scheme A) and Actrapid-Protaphane (scheme B) were administered during 3 months each, in a randomized order, to 18 outpatients. The glycemic control was evaluated by home glucose monitoring, as well as by the monthly measurements of HbA1. The total daily dose of insulin was comparable during each treatment period: 0.68 +/- 0.06 (scheme A) and 0.71 +/- 0.06 U/kg body wt. (scheme B) (mean +/- SEM). However, the total percentage of regular insulin was higher with Monotard than with Protaphane: 58 +/- 3 vs 48 +/- 5% in the morning (p less than 0.005) and 51 +/- 2 vs 46 +/- 3% in the evening (p less than 0.05). In C-peptide positive patients, the blood glucose values were comparable at all times with either insulin scheme. In contrast, in C-peptide negative patients, the blood glucose levels were higher in the afternoon with scheme B: 11.8 +/- 1 vs 8.6 +/- 1 mmol/l at 3 pm (p less than 0.02) and 12.2 +/- 1.3 vs 9.7 +/- 1.6 mmol/l at 6 pm (p less than 0.01). A slight but not significative increase of HbA1 was observed during the B period. In conclusion, an Actrapid-Protaphane scheme requires the use of a lower proportion of regular insulin than an Actrapid-Monotard treatment.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Chemistry, Pharmaceutical; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Middle Aged | 1987 |
A within patient cross over trial of 4 insulin regimens in antibody-negative, C-peptide negative patients.
12 patients entered a within patient cross over trial of 4 insulin regimens:--twice daily semi-synthetic human soluble and insulin zinc suspension (Actrapid/Monotard HM), twice daily porcine soluble and insulin zinc suspension (Actrapid/Monotard), twice daily porcine soluble and isophane insulin (Velosulin/Insulatard), and thrice daily porcine soluble insulin (Actrapid) supplementing once daily bovine ultralente insulin (Ultratard). Each insulin regimen lasted 10 weeks, the order of allocation being determined on a random basis. Patients were encouraged to improve glycaemic control throughout the study by self adjustment of insulin dosage guided by standard algorithms. Metabolic control was assessed by capillary blood glucose series, M-values, HbA1c, and fasting lipids. No significant differences in M-values, mean HbA1c or fasting lipids were found at the end of any of the regimens. Patients achieved significantly (p less than 0.01) lower pre-lunch blood glucose on Velosulin/Insulatard than on any other regimen, but severe hypoglycaemic events were more common (p less than 0.05) on this regimen. A significant fall in HbA1c values from that at recruitment could be demonstrated only by analysing treatment periods in chronological order. Thus at the end of the second study period, mean HbA1c was significantly less than that at recruitment (p less than 0.01), but by the end of the 4 treatment periods of our study, had returned to levels similar to those at recruitment. Similar control is achieved on semi-synthetic human insulin as on other conventional regimens. Day-to-day variability of blood glucose, expressed as a standard deviation, is approximately twice the maximum difference between any 2 regimens at any time point.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Autoantibodies; Blood Glucose; C-Peptide; Cholesterol; Circadian Rhythm; Diabetes Mellitus, Type 1; Humans; Insulin; Metabolic Clearance Rate; Species Specificity; Triglycerides | 1987 |
Trial of mild immunosuppression by methisoprinol in acute onset diabetes mellitus: effects on rate and duration of remission.
There is a lot of data that suggests the immune system plays a role in the pathogenesis of Type 1 DM. Methisoprinol, an immunomodulatory drug, has been reported as being efficient in preventing DM induced by a low dose of streptozotocin in mice. The efficiency of this drug in Type 1 DM was assessed by the rate and duration of remission obtained in recent acute onset DM by strict blood glucose control. We used 2 different therapeutic procedures successively: one was short in an anti-viral aim (50 mg/kg body wt. daily during 10 days) and the other longer given as immunomodulatory treatment (50 mg/kg body wt. daily during 2 weeks and 30 mg/kg body wt. daily during 4 weeks more) with reinduction (30 mg/kg body wt. daily during 4 weeks) every 5 months. No side effect was observed during the treatment. In both studies there was no improvement in the rate and duration of remission when compared to controls; residual beta-cell function was not increased after treatment by methisoprinol. Mild immunotherapy did not appear helpful in Type 1 DM. Topics: Adolescent; Adult; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Humans; Immunosuppression Therapy; Inosine; Inosine Pranobex; Male; Remission Induction | 1986 |
Somatostatin analog SMS 201-995 and insulin needs in insulin-dependent diabetic patients studied by means of an artificial pancreas.
SMS 201-995 is a new somatostatin analog which is 10-60 times more potent and specific than somatostatin as an inhibitor of GH and insulin release. The aim of this study was to assess its value as an adjunct to insulin therapy in insulin-dependent diabetic- (IDD) patients. Six IDD patients were studied. Their average insulin doses ranged from 22-46 U/day, and hemoglobin A1c levels varied between 6.5-11.5%. Two patients had background retinopathy and mild sensorimotor neuropathy. After 12 h of glucemic stabilization, the patients were kept normoglycemic by connecting them to the Biostator-GCIIS. The study entailed two parts in random order, in which standardised mixed meals were administered at 0800, 1400, and 2000 h with or without sc bolus injections of 50 micrograms SMS 201-995 immediately before meal ingestion. Plasma free insulin, C-peptide, GH, and glucagon were measured by RIA. Postprandial hyperglycemia was significantly diminished by SMS 201-995 after breakfast, lunch, and dinner. Insulin requirements, both total and 2-h postprandially, decreased significantly with a parallel reduction in free insulin levels. Postprandial glucagon levels also significantly decreased, but GH profiles were similar. In conclusion, the somatostatin analog SMS 201-995 has a potential value as an adjunct to insulin in the management of IDD patients. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Growth Hormone; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged; Monitoring, Physiologic; Octreotide; Somatostatin | 1986 |
Glipizide does not affect absorption of glucose and xylose in diabetics without residual beta-cell function.
We have previously demonstrated that oral glipizide suppresses the absorption of xylose in diabetics treated with diet alone. We suggested that glipizide might influence postprandial glucose levels by interfering with absorptive mechanisms. In the present study we have extended our observations to insulin-dependent diabetics (IDDM). Nine non-obese diabetics without residual beta-cell function and with normal respiratory sinus arrhythmia and Valsalva ratio were studied on two occasions. Their ordinary insulin treatment was discontinued 24 hours before the study and glucose control was maintained by i.v. insulin infusion. The experiments began at 8 a.m. after an overnight fast. Insulin was given as a continuous i.v. infusion of 0.01 U/kg/h at 8-11 a.m. and 0.005 U/kg/h at 11 a.m. -2 p.m. At 8 a.m. the patients ingested 25 g of xylose and 15 g of glucose in 300 ml of water. Glipizide (5 mg) or placebo were given 30 min prior to the glucose-xylose load in random order, each patient serving as his own control. Blood samples were taken every 60 min for analysis of glucose, xylose, C-peptide and glipizide. The rise in blood glucose in the control experiment was similar to that previously seen in non-insulin-dependent diabetics (NIDDM) given the same xylose-glucose load. Glipizide did not exert any effects on either blood C-peptide, glucose or xylose levels. We conclude that oral glipizide administered in a therapeutic dose does not reduce xylose absorption in IDDM, in contrast to its previously demonstrated effect in NIDDM. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glipizide; Glucose Tolerance Test; Humans; Intestinal Absorption; Islets of Langerhans; Sulfonylurea Compounds; Xylose | 1986 |
Randomized trial of computer-assisted insulin delivery in patients with type I diabetes beginning pump therapy.
Sixteen patients with type I diabetes were randomly assigned to two groups to evaluate the utility of computer-assisted insulin dosage decision-making. All patients used the same solid-phase reagent strip system for glucose measurement and the same pump. The standard group (n = 9) used standard algorithms for insulin adjustment, whereas the computer group (n = 7) relied on interactive instruction from a small, inexpensive (less than $100) computer. At the beginning of the study, there were no significant differences between groups in C-peptide level, hemoglobin A1c level, age, or duration of diabetes. Mean blood glucose level during the study for the computer group was 121 mg/dl (6.7 mM), which was significantly lower (p less than 0.01) than glucose levels charted by the standard group: 148 mg/dl (8.2 mM). Mean number of blood glucose values charted by the computer group (58 per week) was significantly (p less than 0.01) greater than the number charted by the standard group (51 per week). Hemoglobin A1c values at six weeks correlated with the mean number of blood glucose values charted per week of the study. There was no difference between groups in symptomatic hypoglycemic episodes. Computer-assisted insulin dose decision-making is feasible, safe, and effective in enabling persons with type I diabetes mellitus to achieve lower mean blood glucose values over a six-week period while initiating pump therapy. Topics: Adult; Blood Glucose; C-Peptide; Clinical Trials as Topic; Computers; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin Infusion Systems; Male; Middle Aged; Random Allocation | 1986 |
Relationship between changes in GIP concentrations and changes in insulin and C-peptide concentrations after guar gum therapy.
In order to elucidate the mechanisms of the action of gel-forming fibre in diabetes, we measured insulin, C-peptide and GIP responses to meals during treatment with guar gum and placebo in normal and non-insulin-dependent diabetic (NIDD) subjects. Dietary supplementation with guar gum caused a sustained reduction of the GIP response in normal and diabetic subjects (p less than 0.05), but did not influence insulin responses. On the other hand, guar gum increased the C-peptide response to meals in normal subjects (p less than 0.05) resulting in a 40% decrease of the insulin/C-peptide ratio (p less than 0.01). Assuming that the insulin/C-peptide ratio reflects the hepatic extraction of insulin, this would be compatible with increased hepatic removal of insulin. The change in insulin/C-peptide ratio was positively correlated with the change in GIP response after guar gum (r = 0.75; p less than 0.001) and this correlation was strengthened in normal subjects (r = 0.91; p less than 0.001). Our data thus suggest that guar gum stimulates rather than suppresses insulin secretion. The apparent insulinotropic action of GIP may partly be explained by a reduced hepatic extraction of insulin. Topics: Adult; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Galactans; Gastric Inhibitory Polypeptide; Glucagon; Humans; Insulin; Lipids; Male; Mannans; Middle Aged; Plant Gums; Random Allocation | 1986 |
Effect of two periods with intensified insulin treatment on B-cell function during the first 18 months of type 1 (insulin-dependent) diabetes mellitus.
Fifteen consecutive type 1 (insulin-dependent) diabetics were randomized within 24 hrs of diagnosis of the disease into two groups for treatment: group A (N = 9) was treated conventionally with one or two daily doses of insulin, group B (N = 6) was treated with nine daily injections of fast-acting insulin for ten days after diagnosis and for 7 days after 15 months duration of diabetes. For remaining time group B was treated conventionally like group A. The mean diurnal blood glucose concentration during the initial ten days of insulin treatment was 11.7 +/- 0.5 mmol/l (mean +/- SEM) in group A and 6.4 +/- 0.3 mmol/l in group B (P less than 0.01) and 6.0 +/- 0.3 mmol/l in group B during the 7 days with intensified treatment 15 months later. B-cell function was assessed from the C-peptide response to a standard meal 17 and 14 days and 3, 6, 9, 12, 15 and 18 months after start of insulin treatment. After 14 days the C-peptide response was significantly higher (60%) in group B than in group A (P less than 0.05). The second period with strict control improved B-cell function in 4 out of 5 patients with B-cell function. At no test other than after 14 days was there any difference in B-cell function between the groups. Short-term improvement of glycaemic control at onset of disease and after the remission period seem without effect on the long-term outcome of B-cell function in type 1 (insulin-dependent) diabetics. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Humans; Insulin; Islets of Langerhans; Male; Random Allocation; Time Factors | 1986 |
Human insulin: a double-blind clinical study of its effectiveness.
Over a two-year period, 88 patients were evaluated in a double-blind study of human insulin (recombinant DNA origin) and Iletin II pork insulin. Patient follow-up was done throughout the program by glycohemoglobin assays and self-monitoring of blood glucose levels. The C peptides were studied before and after a test meal of Sustacal. Insulin antibody determinations were made regularly. Dietary management was supervised throughout the study. Topics: Antibodies; Blood Glucose; C-Peptide; Cholesterol; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diet, Diabetic; DNA, Recombinant; Double-Blind Method; Humans; Insulin; Self Care | 1985 |
Increase in remission rate in newly diagnosed type I diabetic subjects treated with azathioprine.
Azathioprine (2 mg/kg) was given, in addition to routine insulin treatment, to alternate patients presenting with recent-onset type I diabetes. Treated (N = 13) and untreated (N = 11) patients did not differ significantly at diagnosis with respect to age, duration of symptoms, body weight, blood glucose, hemoglobin A1c, or presence of ketosis. Eight patients were treated for 12 mo, three elected to stop treatment at 6 mo, and treatment was stopped in two because of side effects. Seven treated patients had a remission compared with one untreated patient. At 12 mo these seven patients were distinguished by significantly higher basal and glucagon-stimulated levels of C-peptide (1.98 +/- 0.52 and 3.88 +/- 0.34 micrograms/L, respectively) compared with the other six treated patients (0.93 +/- 0.52 and 1.32 +/- 0.85 microgram/L, respectively), and by the persistence of islet cell cytoplasmic antibodies. Remissions were not sustained in the 1-2 yr after treatment, although relapsed patients required less insulin for control. These results corroborate those from nonrandomized trials using cyclosporine and suggest that protracted treatment with nonspecific immunosuppressive drugs may be necessary to avert insulin dependence. Topics: Adolescent; Adult; Azathioprine; Blood Glucose; C-Peptide; Clinical Trials as Topic; Cyclosporins; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Male; Middle Aged; Random Allocation | 1985 |
Sulphonylurea and insulin: combined treatment in type 1 (insulin-dependent) diabetes.
Topics: C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Drug Therapy, Combination; Glyburide; Humans; Insulin | 1985 |
Effects of dietary fiber on postprandial glycemic profiles in diabetic patients submitted to continuous programmed insulin infusion.
Conventional (C) or fiber supplemented (F) test breakfast and lunch were given on 3 successive randomized days to six insulin-dependent diabetic patients treated with continuous programmed insulin infusion. Meal distribution was as follows: day 1 (C breakfast and C lunch), day 2 (F breakfast and C lunch), day 3 (F breakfast and F lunch). No rise in blood glucose (BG) was observed after F breakfast (days 2 and 3) while a small rise in BG occurred after the C breakfast (day 1). Significant differences were observed between day 1 and days 2 and 3 for absolute BG values as well as for BG changes (delta BG) from base-line. At lunch slight differences in delta BG were only noted at 45 min (p less than 0.05) between days 2 and 3, while there was no difference between days 1 and 2. Our results indicate that fiber supplementation is useful even in pump-treated insulin-dependent diabetics but that F breakfasts have no influence on the carbohydrate tolerance to the subsequent lunch. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dietary Fiber; Glucagon; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged; Random Allocation | 1984 |
Metabolic control in newly diagnosed type 1 diabetic children. Effect of continuous subcutaneous infusion.
15 insulin-dependent diabetic children at onset were randomly allocated to one of two different therapeutical protocols: continuous subcutaneous insulin infusion (CSII) and intensified conventional insulin treatment with three daily insulin injections (CIT). Both treatments were performed for 10 days; the initial insulin dose was 1.5 U/kg/day and thereafter the insulin dosage was modified in order to obtain a satisfactory control. Near-normal blood glucose levels were obtained after 24 h in the CSII group, and after 3 days in the CIT group. All subjects underwent 1 year of follow-up. HbA1 levels and insulin requirements decreased similarly in the two groups; C-peptide secretion did not increase significantly in both groups. A clear advantage of CSII cannot be assumed, and the usefulness of this therapeutical approach needs to be confirmed by further investigations. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Male; Remission, Spontaneous | 1984 |
Sustained normoglycemia in newly diagnosed type I diabetic subjects. Short-term effects and one-year follow-up.
The impact on remission of normalizing blood glucose levels immediately after diagnosis of type I diabetes was studied in 14 adolescents. Accordingly, in this randomized prospective primary intervention study, 7 of the subjects (i.v. group) received insulin by continuous intravenous (i.v.) infusion via a portable preprogrammed system for 28-62 days and 7 (s.c. group) received conventional subcutaneous (s.c.) therapy. Before therapy, the two groups did not differ significantly with respect to glycosylated hemoglobin, fasting plasma C-peptide, or 24-h urinary C-peptide excretion. During the infusion period, the overall mean fasting plasma glucose (FPG) concentration for the i.v. group was 84 mg/dl with a mean coefficient of variation of 18 +/- 4% (mean +/- SD). During the comparable period for the s.c. group, the mean FPG was 253 mg/dl with a coefficient of variation of 30 +/- 20%. Twenty-four-hour urinary glucose excretions for the two groups were 0.29 +/- 0.06 (mean +/- SEM) and 59 +/- 11 g/day, respectively. Daily insulin requirements in the i.v. group decreased from 1.47 +/- 0.19 U/kg body wt/day at the start to 0.47 +/- 0.10 U/kg/day at the end of the infusion period. Notably, 10-25 days after the infusion period, 5 of 7 subjects experienced a further decrease to a low of 0.27 +/- 0.01 U/kg/day. The mean peak and low requirements in the s.c. group were 0.71 +/- 0.15 and 0.33 +/- 0.13 U/kg/day, respectively, with the only peak requirements being significantly different (P less than 0.01). No patient was able to discontinue insulin therapy.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Male | 1984 |
Semisynthetic human insulin and purified pork insulin do not differ in their biological potency.
The biological potency of semisynthetic human insulin (Actrapid HM, Novo) and purified pork insulin (Actrapid MC, Novo) was assessed in normal and diabetic subjects. The blood glucose lowering effect and the related counter-regulatory response were initially tested in six healthy subjects who received an i.v. injection of 0.15 U/kg body weight of either insulin preparation. The attained insulin levels were very similar (peak at 15 min: HM 139 +/- 7, MC 129 +/- 7 microU/ml), as well as the resulting blood glucose curves. A prolonged suppression of C-peptide values was observed after injecting both preparations. The evoked counter-regulatory response [glucagon, growth hormone (GH), cortisol and catecholamines] showed minimal differences. Prolactin secretion was almost identical after HM and MC injection. A glucose clamp study was subsequently performed in six insulin-dependent diabetic (IDD) patients. Blood glucose levels were maintained at 80 mg/dl by the artificial pancreas during a 180 min infusion of MC or HM insulin (30 mU/kg/h). The amounts of dextrose infused during the last 60 min of the study were not significantly different (121 +/- 14 vs 137 +/- 11 mg/kg/h for MC and HM, respectively). It is clear from our results that at the dose levels used in this study, the biological potency of i.v. injected HM is very similar to that of MC. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Glucagon; Growth Hormone; Humans; Hydrocortisone; Insulin; Insulin, Regular, Pork; Male; Norepinephrine; Prolactin | 1984 |
Improved diabetic control in insulin-dependent diabetics treated with insulin and glibenclamide.
A randomized double blind trial of insulin and glibenclamide treatment vs insulin and placebo was carried out in 20 insulin-dependent diabetics. Nine patients were C-peptide secretors and all increased their C-peptide output during a 50 g OGTT at the end of the insulin and glibenclamide treatment period by a mean of 47%. At the same time their mean daily blood glucose fell from 8.4 +/- 1.7 to 7.4 +/- 1.5 mmol/l and their HbA1 from 8.1 +/- 0.5 to 7.5 +/- 0.9% (mean +/- SD). There was no change in any of the measurements of diabetic control in C-peptide non-secretors and no evidence for any extra-pancreatic effects of glibenclamide in this group of patients. Combined insulin and glibenclamide treatment may produce a useful improvement of diabetic control in insulin-dependent diabetics who still secrete some endogenous insulin, although further studies are required. Topics: Adult; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glyburide; Humans; Insulin; Male; Random Allocation | 1984 |
Methodological aspects on C-peptide measurements.
It is rather difficult to draw conclusions from reported C-peptide values, as the methods for determination differ, and C-peptide may be measured in serum or in urine with the patient fasting or after stimulation. We have followed prospectively 49 children with IDDM with regular determinations of serum C-peptide fasting and after a standardized breakfast. A subgroup of seven patients have been studied more thoroughly with 24-hour-profile of serum C-peptide, C-peptide excretion in urine, and stimulation by i.v. glucose + i.v. arginine. Our results indicate that the stimulation of the beta cells usually reaches a maximum around a blood glucose level of 10-12 mmol/l leading to a curve linear relationship between serum C-peptide and blood glucose. Thus a simple quotient is not so useful but the degree of stimulation should be stated and actual blood glucose value noticed. Stimulation with a standardized breakfast gives roughly the same information as maximal stimulation with i.v. glucose + arginine, and little extra information is found by a 24-hour-profile. Urinary C-peptide may give valuable information if it is related to the actual degree of metabolic balance. It can be of special interest in patients with very low serum C-peptide levels. Topics: Adolescent; Arginine; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Eating; Female; Glucose; Humans; Male; Peptides | 1983 |
Metabolic and circulatory effects of oral salbutamol in the third trimester of pregnancy in diabetic and non-diabetic women.
Metabolic and cardiovascular effects of 4 mg oral salbutamol were studied in ten non-diabetic, ten chemical diabetic and five juvenile diabetic women in late pregnancy. None of the women had been treated with beta-sympathomimetic drugs earlier in their pregnancy. Heart rate and blood pressure were recorded and blood samples for measurement of plasma cyclic AMP, insulin, C-peptide, glucose, lactate, glycerol, non-esterified fatty acids (NEFA) and 3-hydroxybutyrate (3-HB) were collected every 30 minutes for 120 minutes after salbutamol. All women underwent the same procedure at random without salbutamol. There were significant cardiovascular effects of salbutamol in all the groups but no differences in these effects between the groups. Salbutamol caused significant increases of glycogenolysis and lipolysis in all the groups, significantly larger in the juvenile diabetic than the non-diabetic and chemical diabetic women. This observation could be explained by the inability of the juvenile diabetics to secrete insulin, shown by their non-measureable plasma C-peptide levels. The metabolic responses following salbutamol in the chemical diabetics were intermediate between the non-diabetic and juvenile diabetic groups. The results show that diabetes does not alter the sensitivity of beta-receptors involved in cardiovascular regulation, while the metabolic responses to oral salbutamol are enhanced, especially in juvenile diabetics. We suggest that during treatment with beta-sympathomimetic drugs, blood glucose should be monitored in all patients showing criteria of potential diabetes. Topics: Adult; Albuterol; Blood Glucose; C-Peptide; Cyclic AMP; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glycerol; Hemodynamics; Humans; Hydroxybutyrates; Insulin; Lactates; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Third | 1981 |
Comparison of single- and split-dose insulin regimens with 24-hour monitoring.
It has been asserted that twice daily injections of mixed insulin provide better blood glucose control than one. To compare the two regimens we conducted a random-order, double-crossover trial in ten diabetic children. Each regimen lasted for six weeks, concluding with a hospital evaluation. Control at home was assessed by a urine log and determination of glycosylated hemoglobin. Control in the hospital was assessed with measurements of quantitative urinary glucose, serum lipids, and by 24-hour blood sampling for glucose, C-peptide, and counterregulatory hormones. For the group as a whole, none of the indices of control demonstrated a significant advantage for either regimen. Individually, several children did appear to achieve better control on one regimen than the other. Indices of control at home did not consistently predict control in the hospital. In the hospital, the largest increases in glucose concentration followed breakfast (mean rise 148 mg/dl), and standardized exercise invariably reduced plasma glucose values (mean decrement 60 mg/dl). C-Peptide concentrations were low, but higher values were associated with better control. Although a split insulin regimen may improve metabolic control in some patients, this study did not demonstrate a substantial advantage for the majority of subjects over the short period of the trials. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Cholesterol; Circadian Rhythm; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Monitoring, Physiologic; Prospective Studies; Random Allocation; Triglycerides | 1981 |
Timing of pre-breakfast insulin injection and postprandial metabolic control in diabetic children.
A peak period of hyperglycaemia in insulin-dependent diabetics occurs after breakfast. A randomised crossover study was performed on nine diabetic children at home to study the effect of varying the time of their morning mixed injection of Monotard and Actrapid insulin on this hyperglycaemic peak. Performing the study at home minimised the children's stress.After diabetic control had been improved children injected their insulin 30 minutes (early injection) or five minutes (late injection) before breakfast on two consecutive Saturday mornings. Blood samples were taken at 30-minute intervals over 3(1/2) hours and analysed for concentrations of glucose, insulin, C-peptide, pyruvate, lactate, alanine, and ketones. Diet, insulin dose, and exercise were kept the same on both test days.The mean blood glucose concentration at breakfast (0 minutes) was 11 mmol/l after the early injection and 10 mmol/l after the late injection. Subsequent concentrations were consistently lower with the early injection regimen than the late regimen. The greatest difference between values in the two groups was 3.7 mmol/l at 150 minutes. Mean plasma insulin concentrations were lower in the children on the early regimen than in those on the late regimen at 30 minutes before breakfast but higher at 0 minutes and thereafter. There were no significant differences in mean concentration of intermediary metabolites between the two injection regimens. These were mainly within the normal range for healthy young adults except for the ketone concentrations, which were raised with both injection regimens until 180 minutes after breakfast.These results suggest that the timing of the morning injection of insulin is important in the control of postprandial hyperglycaemia in diabetic children. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Administration Schedule; Food; Humans; Hyperglycemia; Insulin; Ketones; Time Factors | 1980 |
Twenty-four-hour metabolic profiles in diabetic children receiving insulin injections once or twice daily.
Twenty-four-hour metabolic profiles were performed twice in each of 15 diabetic children, once when they were receiving single daily injections of insulin (Monotard plus Actrapid) and once on a twice-daily regimen (Semitard plus Actrapid). Before the study control was optimised at home on each regimen. There were no differences in overall 24-hour diabetic control on the two regimens as measured by mean blood glucose concentration, area under the blood glucose curve, M value, and 24-hour urinary glucose excretion. Hyperglycaemia after breakfast occurred on both regimens. Significant differences were noted before breakfast, when blood glucose and ketone concentrations were lower and plasma free insulin higher on the single-injection regimen, and after supper and during the night, when blood glucose values were lower on the two-injection regimen and associated with a rise in plasma free insulin after the evening injection. Once-daily injections provided insufficient circulating insulin after the evening meal, while twice-daily injections did not last through the night. Plasma C peptide, indicating residual endogenous insulin secretion, was just detectable in two children but easily detectable in four children, whose 24-hour diabetic control was significantly better than that in the remaining 11 children.Conclusions about the superiority of one insulin regimen over another must be based on specific differences in diabetic control. Both regimens studied achieved adequate control, and though neither provided physiological control specific modifications to the regimens could help to produce more normal profiles. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Circadian Rhythm; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Food; Glycosuria; Humans; Injections, Intravenous; Insulin; Ketones; Male | 1980 |
1558 other study(ies) available for c-peptide and Diabetes-Mellitus--Type-1
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The impact of family history of type 2 diabetes on clinical heterogeneity in idiopathic type 1 diabetes.
To investigate the impact of family history of type 2 diabetes (T2D) on the clinical phenotypes of patients with idiopathic type 1 diabetes (T1D).. In clinically diagnosed T1D cases, a total of 335 idopathic T1D patients were included in the study, after excluding autoimmune T1D using islet autoantibody testing and monogenic diabetes using a custom monogenic diabetes gene panel obtained from clinically diagnosed T1D cases. A semi-structured questionnaire was used to collect information on the presence of T2D in first-degree relatives. The demographic and metabolic markers of idiopathic T1D patients were analysed. Subgroup analysis was performed to investigate potential interactions between T2D family history and human leukocyte antigen (HLA) genotypes.. A total of 18.2% of individuals with idiopathic T1D had a T2D family history, and these individuals were more likely to have features associated with T2D, such as older age of onset, higher body mass index at diagnosis, lower insulin dosage and better beta-cell function, as indicated by higher levels of fasting C-peptide and 2-hour postprandial C-peptide (all P < 0.05). Additionally, regardless of HLA susceptible genotypes, the impact of family history of T2D was consistently observed in idiopathic T1D patients. Multivariable analyses showed that T2D family history was negatively correlated with the risk of beta-cell function failure in idiopathic T1D patients (P < 0.05).. Family history of T2D may be implicated in the heterogeneity of idiopathic T1D patients. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Genotype; Humans; Insulin | 2023 |
Hypoglycemia Caused by Exogenous Insulin Antibody Syndrome: A Large Single-Center Case Series From China.
Exogenous insulin antibody syndrome (EIAS) can lead to unexpected and potentially life-threatening recurrent hypoglycemia.. We aimed to better define autoimmune hypoglycemia caused by EIAS in patients with diabetes and shed light on the improvements in the identification and intervention for this rare but possibly life-threatening condition.. We summarized the clinical characteristics of autoimmune hypoglycemia caused by EIAS in 23 patients with diabetes. Furthermore, we performed human leukocyte antigen (HLA) genotyping of 10 patients.. We identified a high frequency of autoimmune comorbidities (21.7%), food or drug allergy (48%), insulin allergy (30%), lipodystrophy at the insulin injection sites (22%), and antinuclear antibodies (25%) in the patients. Alternation between hyperglycemia and hypoglycemia was observed in more than 90% of the patients. Most patients showed a high insulin autoantibody titer (>90%) and inappropriately increased insulin concentration (insulin/C-peptide molar ratio >7, >85%). We detected similar frequencies of DRB1*0405-DQB1*0401 and DRB1*0901-DQB1*0303 compared with previously reported frequencies in type 1 diabetes, and a lower frequency of DRB1*0406 compared with insulin autoimmune syndrome. The spontaneous remission rate exceeded 70%.. Predisposing factors for autoimmune hypoglycemia caused by EIAS include a strong autoimmune background. Susceptible HLA genotypes for type 1 diabetes or insulin autoimmune syndrome might not explain susceptibility to this condition. Additionally, insulin autoantibodies and the insulin/C-peptide molar ratio are reliable screening options. The prognosis for this condition is favorable. Monitoring of insulin and insulin autoantibodies may contribute to treatment effectiveness. Topics: Autoantibodies; Autoimmune Diseases; C-Peptide; China; Diabetes Mellitus, Type 1; HLA-DRB1 Chains; Humans; Hypoglycemia; Insulin; Insulin Antibodies; Syndrome | 2023 |
C-peptide Targets and Patient-centered Outcomes of Relevance to Cellular Transplantation for Diabetes.
C-peptide levels are a key measure of beta-cell mass following islet transplantation, but threshold values required to achieve clinically relevant patient-centered outcomes are not yet established.. We conducted a cross-sectional retrospective cohort study evaluating patients undergoing islet transplantation at a single center from 1999 to 2018. Cohorts included patients achieving insulin independence without hypoglycemia, those with insulin dependence without hypoglycemia, and those with recurrent symptomatic hypoglycemia. Primary outcome was fasting C-peptide levels at 6 to 12 mo postfirst transplant; secondary outcomes included stimulated C-peptide levels and BETA-2 scores. Fasting and stimulated C-peptide and BETA-2 cutoff values for determination of hypoglycemic freedom and insulin independence were evaluated using receiver operating characteristic curves.. We analyzed 192 patients, with 122 (63.5%) being insulin independent without hypoglycemia, 61 (31.8%) being insulin dependent without hypoglycemia, and 9 (4.7%) experiencing recurrent symptomatic hypoglycemia. Patients with insulin independence had a median (interquartile range) fasting C-peptide level of 0.66 nmol/L (0.34 nmol/L), compared with 0.49 nmol/L (0.25 nmol/L) for those being insulin dependent without hypoglycemia and 0.07 nmol/L (0.05 nmol/L) for patients experiencing hypoglycemia ( P < 0.001). Optimal fasting C-peptide cutoffs for insulin independence and hypoglycemia were ≥0.50 nmol/L and ≥0.12 nmol/L, respectively. Cutoffs for insulin independence and freedom of hypoglycemia using stimulated C-peptide were ≥1.2 nmol/L and ≥0.68 nmol/L, respectively, whereas optimal cutoff BETA-2 scores were ≥16.4 and ≥5.2.. We define C-peptide levels and BETA-2 scores associated with patient-centered outcomes. Characterizing these values will enable evaluation of ongoing clinical trials with islet or stem cell therapies. Topics: Blood Glucose; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Hypoglycemia; Insulin; Islets of Langerhans Transplantation; Patient-Centered Care; Retrospective Studies | 2023 |
Clinical signs of type 1 diabetes are associated with type 2 diabetes marker transcription factor 7-like 2 polymorphism.
We aimed to assess the distribution of transcription factor 7-like 2 gene TCF7L2 (rs7903146) polymorphism and to find possible associations between TCF7L2 and the characteristics of type 1 diabetes.. We studied 190 newly diagnosed type 1 diabetes patients (median age 12.7 years, range 2.0-72.5) and 246 controls (median age 23.8 years, range 1.4-81.5) for TCF7L2 single nucleotide polymorphism. We determined anti-islet autoantibodies, random C-peptide levels, diabetes associated HLA DR/DQ haplotypes and genotypes in all patients.. There were no differences in the distribution of TCF7L2 single nucleotide polymorphism between patients and controls. However, patients with in type 1 diabetes, after adjusting for age and sex, subjects carrying C allele were at risk for a C-peptide level lower than 0.5 nmol/L (OR 5.65 [95% CI: 1.14-27.92]) and for zinc transporter 8 autoantibody positivity (5.22 [1.34-20.24]). Participants without T allele were associated with a higher level of islet antigen-2 autoantibodies (3.51 [1.49-8.27]) and zinc transporter 8 autoantibodies (2.39 [1.14-4.99]).. The connection of TCF7L2 polymorphism with zinc transporter 8 and islet antigen-2 autoantibodies and C-peptide levels in patients supports the viewpoint that TCF7L2 is associated with the clinical signs and autoimmune characteristics of type 1 diabetes. The mechanisms of the interaction between the TCF7L2 risk genotype and anti-islet autoantibodies need to be studied further. Topics: Adolescent; Adult; Aged; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genotype; Humans; Middle Aged; Polymorphism, Single Nucleotide; T Cell Transcription Factor 1; Young Adult; Zinc Transporter 8 | 2023 |
Fasting and meal-stimulated serum C-peptide in long-standing type 1 diabetes mellitus.
This study aims to evaluate the stability of C-peptide over time and to compare fasting C-peptide and C-peptide response after mixed-meal tolerance test (MMTT) at T90 or T120 with C-peptide area under the curve (AUC) in long-standing type 1 diabetes.. We included 607 type 1 diabetes individuals with diabetes duration >5 years. C-peptide concentrations (ultrasensitive assay) were collected in the fasting state, and in a subpopulation after MMTT (T0, just prior to, T30-T60-T90-T120, 30-120 min after ingestion of mixed-meal) (n = 168). Fasting C-peptide concentrations (in n = 535) at Year 0 and Year 1 were compared. The clinical determinants associated with residual C-peptide secretion and the correspondence of C-peptide at MMTT T90 / T120 and total AUC were assessed.. A total of 153 participants (25%) had detectable fasting serum C-peptide (i.e ≥ 3.8 pmol/L). Fasting C-peptide was significantly lower at Year 1 (p < 0.001, effect size = -0.16). Participants with higher fasting C-peptide had a higher age at diagnosis and shorter disease duration and were less frequently insulin pump users. Overall, 109 of 168 (65%) participants had both non-detectable fasting and post-meal serum C-peptide concentrations. The T90 and T120 C-peptide values at MMTT were concordant with total AUC. In 17 (10%) individuals, C-peptide was only detectable at MMTT and not in the fasting state.. Stimulated C-peptide was detectable in an additional 10% of individuals compared with fasting in individuals with >5 years of diabetes duration. T90 and T120 MMTT measurements showed good concordance with the MMTT total AUC. Overall, there was a decrease of C-peptide at 1-year follow-up. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Humans; Insulin; Insulin-Secreting Cells; Meals | 2023 |
Distribution of autoantibodies to insulinoma-associated antigen-2 and zinc transporter 8 in type 1 diabetes and latent autoimmune diabetes: A nationwide, multicentre, cross-sectional study.
This study investigated insulinoma-associated-2 autoantibody (IA-2A) and zinc transporter 8 autoantibody (ZnT8A) distribution in patients with type 1 diabetes (T1D) and latent autoimmune diabetes (LAD) and the autoantibodies' association with clinical characteristics and HLA-DR-DQ genes.. This cross-sectional study recruited 17,536 patients with diabetes from 46 hospitals across China. A total of 189 patients with T1D and 58 patients with LAD with IA-2A positivity, 126 patients with T1D and 86 patients with LAD with ZnT8A positivity, and 231 patients with type 2 diabetes (T2D) were selected to evaluate islet autoantibodies, clinical phenotypes, and HLA-DR-DQ gene frequency.. IA-2A was bimodally distributed in patients with T1D and LAD. Patients with low IA-2A titre LAD had lower fasting C-peptide (FCP) (p < 0.01), lower postprandial C-peptide (PCP) (p < 0.001), and higher haemoglobin A1c (HbA1c) levels (p < 0.05) than patients with T2D. Patients with high IA-2A titre LAD were younger than patients with low IA-2A titre LAD (p < 0.05). Patients with low IA-2A titre T1D had lower FCP (p < 0.01), lower PCP (p < 0.01), and higher HbA1c levels (p < 0.05) than patients with high IA-2A titre LAD. HLA-DR-DQ genetic analysis demonstrated that the frequency of susceptible HLA haplotypes was higher in IA-2A-positive patients (p < 0.001) than in patients with T2D. Patients with high ZnT8A titre LAD had lower FCP (p = 0.045), lower PCP (p = 0.023), and higher HbA1c levels (p = 0.009) and a higher frequency of total susceptible haplotypes (p < 0.001) than patients with low ZnT8A titre LAD.. IA-2A in patients with T1D and LAD was bimodally distributed, and the presence of IA-2A could demonstrate partial LAD clinical characteristics. ZnT8A titre had a certain predictive value for islet functions in patients with LAD. Topics: Autoantibodies; C-Peptide; Cation Transport Proteins; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Intolerance; Glutamate Decarboxylase; Glycated Hemoglobin; HLA-DR Antigens; Humans; Insulinoma; Pancreatic Neoplasms; Zinc Transporter 8 | 2023 |
Adult-Onset Type 1 Diabetes Development Following COVID-19 mRNA Vaccination.
During the coronavirus disease 2019 (COVID-19) pandemic, COVID-19 vaccination-induced hyperglycemia and related complications have been reported. However, there have been few reports of type 1 diabetes triggered by COVID-19 vaccines in subjects without diabetes. Here, we report the case of a 56-year-old female patient who developed hyperglycemia after the second dose of COVID-19 mRNA-based vaccination without a prior history of diabetes. She visited our hospital with uncontrolled hyperglycemia despite administration of oral hyperglycemic agents. Her initial glycated hemoglobin level was high (11.0%), and fasting serum C-peptide level was normal. The fasting serum C-peptide level decreased to 0.269 ng/mL 5 days after admission, and the anti-glutamic acid decarboxylase antibody was positive. The patient was discharged in stable condition with insulin treatment. To our knowledge, this is the first case of the development of type 1 diabetes without diabetic ketoacidosis after mRNA-based COVID-19 vaccination, and is the oldest case of type 1 diabetes development under such circumstances. Topics: Adult; C-Peptide; COVID-19; COVID-19 Vaccines; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Hyperglycemia; Insulin; Middle Aged; Vaccination | 2023 |
HLA Class I Association With Autoimmune Diabetes in Chinese People: Distinct Implications in Classic Type 1 Diabetes and LADA.
We aimed to investigate whether human leukocyte antigen (HLA) Class I loci differentially modulated the risk for and clinical features of Chinese people with classic type 1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA).. In this case-control study, genotypes of HLA-A, -B, -C, -DRB1, -DQA1, and -DQB1 loci were obtained from 1067 cases with classic T1D, 1062 cases with LADA, and 1107 normal controls using next-generation sequencing.. Despite 4 alleles shared between classic T1D and LADA (protective: A*02:07 and B*46:01; susceptible: B*54:01 and C*08:01), 7 Class I alleles conferred risk exclusively for classic T1D (A*24:02, B*15:02, B*15:18, B*39:01, B*40:06, B*48:01, and C*07:02) whereas only A*02:01 was an additional risk factor for LADA. Class I alleles affected a wide spectrum of T1D clinical features, including positive rate of protein tyrosine phosphatase autoantibody and zinc transporter 8 autoantibody (A*24:02), C-peptide levels (A*24:02), and age at diagnosis (B*46:01, C*01:02, B*15:02, C*07:02, and C*08:01). By contrast, except for the detrimental effect of C*08:01 on C-peptide concentrations in LADA, no other Class I associations with clinical characteristics of LADA could be reported. The addition of Class I alleles refined the risk model consisting only of DR-DQ data in classic T1D while the overall predictive value of the LADA risk model comprising both Class I and II information was relatively low.. The attenuated HLA Class I susceptibility to LADA was indicative of a less deleterious immunogenetic nature compared with classic T1D. These autoimmune diabetes-related Class I variants might serve as additional markers in future screening among Chinese people. Topics: Adult; Autoantibodies; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; East Asian People; Genetic Predisposition to Disease; Humans; Latent Autoimmune Diabetes in Adults | 2023 |
Predictive Value of C-Peptide Measures for Clinical Outcomes of β-Cell Replacement Therapy in Type 1 Diabetes: Report From the Collaborative Islet Transplant Registry (CITR).
To determine C-peptide measures and levels associated with positive glycemic control outcomes following islet transplant (ITx) in type 1 diabetes.. We evaluated Collaborative Islet Transplant Registry (CITR) islet-alone recipients with pretransplant C-peptide <0.1 nmol/L and mean follow-up of 4.6 ± 1.1 years (n = 677). Receiver operating characteristic area under the curve (ROC-AUC) was used to evaluate the predictive value of fasting and stimulated glucose and C-peptide measures for seven primary outcomes: 1) absence of severe hypoglycemic events (ASHEs); 2) HbA1c <7.0%; 3) HbA1c <7.0% and ASHEs; 4) HbA1c ≤6.5%; 5) HbA1c ≤6.5% and ASHEs; 6) insulin independence; and 7) ASHEs, HbA1c ≤6.5%, and insulin independence (the optimal outcome). Measures with the highest ROC-AUC were selected for determination of optimal cut points.. Fasting C-peptide was highly predictive for ASHE (ROC-AUC 0.906; optimal cut point 0.070 nmol/L) and the optimal outcome (ROC-AUC 0.845; optimal cut point 0.33 nmol/L). Mixed-meal tolerance test (MMTT)-stimulated C-peptide-to-glucose ratio (CPGR) outperformed both fasting and stimulated C-peptide for all outcomes except ASHE. The optimal cut point for the optimal outcome was 0.12 nmol/mmol for MMTT-stimulated CPGR and 0.97 nmol/L for MMTT-stimulated C-peptide.. Fasting C-peptide reliably predicts ITx primary outcomes. MMTT-stimulated CPGR provides marginally better prediction for composite ITx outcomes, including insulin independence. In the absence of an MMTT, a fasting C-peptide ≥0.33 nmol/L is a reassuring measure of optimal islet graft function. C-peptide targets represent excellent and easily determinable means to predict glycemic control outcomes after ITx and should be considered as potential goals of β-cell replacement. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin, Regular, Human; Islets of Langerhans Transplantation | 2023 |
Clinical characteristics of 683 children and adolescents, aged 0-18 years, newly diagnosed with type 1 diabetes mellitus in Henan Province: a single-center study.
Type 1 diabetes mellitus (T1DM) is a common chronic systemic disease that threatens the health of children worldwide. Diabetic ketoacidosis (DKA) is the most severe acute complication of diabetes and can lead to death. This study aimed to explore the epidemiological features, clinical manifestations, and risk factors for DKA in children and adolescents newly diagnosed with T1DM in the Department of Endocrinology of the Children's Hospital of Henan Province.. Medical records of 683 children and adolescents newly diagnosed with T1DM in our center from March 2014 to November 2021 were retrospectively analyzed. The data included the general condition, laboratory indexes, and clinical symptoms. The patients were divided into three groups according to age: Group I, 0-3 years; Group II, 4-9 years; and Group III, 10-18 years.. The incidence of DKA was 62.96% and was highest in Group I. Group I had the lowest C-peptide and hemoglobin A1c, but the highest blood glucose at first diagnosis, and 25-hydroxyvitamin D3 levels, hospitalization lengths, and medical costs. 25.5% of the children were delayed in diagnosis. Logistic regression analysis showed that elevated HbA1c levels and hyperglycemia were independent risk factors for DKA. On the other hand, C-peptide and 25- hydroxyvitamin D were protective factors for DKA.. The incidence of DKA among children and adolescents in the Henan Province is very high. Moreover, DKA can be easily delayed in diagnosis. Newly diagnosed infants with T1DM are more likely to present with DKA, suffer more severe metabolic disorders, endure longer hospital stays, and accrue higher medical costs. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Glycated Hemoglobin; Humans; Hyperglycemia; Infant; Infant, Newborn; Retrospective Studies; Risk Factors | 2023 |
Difference in the early clinical course between children with type 1 diabetes having a single antibody and those having multiple antibodies against pancreatic β-cells.
Islet-cell associated antibodies are predictive and diagnostic markers for type 1 diabetes. We studied the differences in the early clinical course of children with type 1 diabetes with a single antibody and those with multiple antibodies against pancreatic β-cells. Sixty-seven children with type 1 diabetes aged less than 15 years diagnosed between 2010 and 2021 were included in the study and subdivided into two subgroups: children who were single positive for either glutamic acid decarboxylase (GAD) antibodies (n = 16) or insulinoma-associated antigen-2 (IA-2) antibodies (n = 13) and those positive for both antibodies (n = 38) at diagnosis. We compared the patients' clinical characteristics, pancreatic β-cell function, and glycemic control during the 5 years after diagnosis. All clinical characteristics at diagnosis were similar between the two groups. One and two years after diagnosis, children who tested positive for both antibodies showed significantly lower postprandial serum C-peptide (CPR) levels than those who tested positive for either GAD or IA-2 antibodies (p < 0.05). In other periods, there was no significant difference in CPR levels between the two groups. There was a significant improvement in glycosylated hemoglobin (HbA1c) levels after starting insulin treatment in both groups (p < 0.05), but no significant difference in HbA1c levels between the groups. Residual endogenous insulin secretion may be predicted based on the number of positive islet-cell associated antibodies at diagnosis. Although there are differences in serum CPR levels, optimal glycemic control can be achieved by individualized appropriate insulin treatment, even in children with type 1 diabetes. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Insulinoma; Male | 2023 |
Clinical and biochemical profile of childhood-adolescent-onset type 1 diabetes and adult-onset type 1 diabetes among Asian Indians.
To compare the clinical and biochemical profile and prevalence of complications among childhood/adolescent-onset (CAO; onset of diabetes< 20 years of age) and adult-onset (AO; onset of diabetes- ≥ 20 years of age) type 1 diabetes (T1D), seen at a tertiary care diabetes center in south India.. Data of 5578 individuals with T1D, diagnosed based on a history of diabetic ketoacidosis or ketonuria, fasting C-peptide < 0.3 pmol/mL and stimulated C-peptide values < 0.6 pmol/mL, and requirement of insulin right from the time of diagnosis, presenting to our center between 1991 and 2021, were retrieved from our electronic medical records. Retinopathy was assessed by retinal photography, chronic kidney disease (CKD) by urinary albumin excretion ≥ 30 µg/mg of creatinine and/or eGFR < 60 mL/min, and neuropathy by vibration perception threshold >= 20v on biothesiometry.. Overall, 3559 (63.8%) of individuals with T1D, belonged to CAO group and 2019 (36.2%) to AO category. AO had higher prevalence of all microvascular complications compared to CAO at every diabetes duration interval, even after adjusting for A1c. Among the AO group, prevalence of retinopathy, CKD, and neuropathy was higher in the GAD negative group. Among CAO there were no differences between the GAD negative and GAD positive groups with respect to prevalence of complications of diabetes.. AO with T1D had higher prevalence of microvascular complications compared to CAO. Among AO, GAD negative individuals had higher percentage of retinopathy and CKD compared to GAD positive group. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Humans; Prevalence; Retinal Diseases | 2023 |
Relationship of Glucose, C-peptide, Leptin, and BDNF in Maternal and Umbilical Vein Blood in Type-1 Diabetes.
The study aimed to determine the relationship between glucose, C-peptide, brain-derived neurotrophic factor (BDNF), and leptin between mother and fetus and neonatal weight.. In the prospective observational cohort study, we included 66 women with type-1 diabetes mellitus (T1DM). According to the z-score for neonatal weight, patients were divided into healthy-weight neonates (. A strong correlation was confirmed between maternal and umbilical vein glucose concentration and maternal glucose and C-peptide in umbilical vein blood. A negative correlation was found between the concentration of BDNF in the umbilical vein and glucose in maternal blood. A strong correlation was seen between BMI and maternal blood leptin concentration, neonatal fat body mass, and umbilical vein blood leptin concentration. Higher BMI elevated BDNF, and TSH increase the odds for overweight neonates in the first trimester of pregnancy. Maternal higher leptin concentration in the first trimester decrease the odds of overweight neonates.. Maternal glucose concentrations affect the fetus's glucose, C-peptide, and BDNF concentrations. Leptin levels increase in maternal blood due to increased body mass index, and in the neonate, fat body mass is responsible for increased leptin concentrations. Topics: Body Mass Index; Brain-Derived Neurotrophic Factor; C-Peptide; Cesarean Section; Diabetes Mellitus, Type 1; Female; Fetal Blood; Glucose; Humans; Infant, Newborn; Leptin; Overweight; Pregnancy; Prospective Studies; Thyrotropin; Umbilical Veins | 2023 |
Age of Diagnosis Does Not Alter the Presentation or Progression of Robustly Defined Adult-Onset Type 1 Diabetes.
To determine whether presentation, progression, and genetic susceptibility of robustly defined adult-onset type 1 diabetes (T1D) are altered by diagnosis age.. We compared the relationship between diagnosis age and presentation, C-peptide loss (annual change in urine C-peptide-creatinine ratio [UCPCR]), and genetic susceptibility (T1D genetic risk score [GRS]) in adults with confirmed T1D in the prospective StartRight study, 1,798 adults with new-onset diabetes. T1D was defined in two ways: two or more positive islet autoantibodies (of GAD antibody, IA-2 antigen, and ZnT8 autoantibody) irrespective of clinical diagnosis (n = 385) or one positive islet autoantibody and a clinical diagnosis of T1D (n = 180).. In continuous analysis, age of diagnosis was not associated with C-peptide loss for either definition of T1D (P > 0.1), with mean (95% CI) annual C-peptide loss in those diagnosed before and after 35 years of age (median age of T1D defined by two or more positive autoantibodies): 39% (31-46) vs. 44% (38-50) with two or more positive islet autoantibodies and 43% (33-51) vs. 39% (31-46) with clinician diagnosis confirmed by one positive islet autoantibody (P > 0.1). Baseline C-peptide and T1D GRS were unaffected by age of diagnosis or T1D definition (P > 0.1). In T1D defined by two or more autoantibodies, presentation severity was similar in those diagnosed before and after 35 years of age: unintentional weight loss, 80% (95% CI 74-85) vs. 82% (76-87); ketoacidosis, 24% (18-30) vs. 19% (14-25); and presentation glucose, 21 mmol/L (19-22) vs. 21 mmol/L (20-22) (all P ≥ 0.1). Despite similar presentation, older adults were less likely to be diagnosed with T1D, insulin-treated, or admitted to hospital.. When adult-onset T1D is robustly defined, the presentation characteristics, progression, and T1D genetic susceptibility are not altered by age of diagnosis. Topics: Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Humans; Prospective Studies | 2023 |
Association of C-peptide level with peripheral neuropathy in type 2 diabetes: An observational cross-sectional preliminary study.
Peripheral neuropathy is the most common microvascular complication of diabetes mellitus. In subjects with type 1 diabetes (T1D) relationship of C-peptide levels and neuropathy has been observed in several studies, however, there are very few studies in type 2 diabetes (T2D) subjects. In this study we aim to assess the association of C-peptide levels with peripheral neuropathy in Indian subjects with T2D.. One hundred patients of T2D were included in this study. Clinical and laboratory parameter was assessed for all participants. The C-peptide level was measured by fluorometric enzyme immunoassay method. Assessment of diabetic peripheral neuropathy was based on diabetic neuropathy symptom score and the diabetic neuropathy examination scores.. Total 100 patients completed the study. Mean age of subjects was 60.03 years and male: female ratio was 1.17. Peripheral neuropathy was detected in 47% of subjects evaluated. Subjects were further divided in to neuropathy group and no-neuropathy group for analysis. Age in neuropathy group was significantly higher than no-neuropathy group [65.62 ± 10.5 vs 55.08 ± 9.41 yrs (p-value <0.0001)] and similarly duration of T2D was significantly higher in neuropathy group [10.11 ± 6.13 vs 4.16 ± 3.7 yrs (p-value <0.0001)]. Importantly mean fasting C-peptide (2.27 ± 0.98 vs 3.12 ± 0.84 ng/ml) and mean post meal C-peptide (4.27 ± 1.34 vs 5.33 ± 0.89 ng/ml) were significantly lower in neuropathy group compared to no-neuropathy group. An association of HbA1c level and neuropathy was statistically not significant (p = 0.793).. Serum C-peptide concentrations are associated with peripheral neuropathy in T2DM patients, independent of the degree of glycemic control. Topics: C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Female; Humans; Male; Middle Aged | 2023 |
Urinary c-peptide creatinine ratio (UCPCR) as a predictor of coronary artery disease in type 1 diabetes mellitus.
Elevated C-peptide has been suggested as a risk factor for coronary artery disease (CAD). Elevated urinary C-peptide to creatinine ratio (UCPCR) as an alternative measurement is shown to be related to insulin secretion dysfunction; however, data regarding UCPCR predictive value for CAD in diabetes mellitus (DM) are scarce. Therefore, we aimed to assess the UCPCR association with CAD in type 1 DM (T1DM) patients.. 279 patients previously diagnosed with T1DM included and categorized into two groups of CAD (n = 84) and without-CAD (n = 195). Furthermore, each group was divided into obese (body mass index (BMI) ≥ 30) and non-obese (BMI < 30) groups. Four models utilizing the binary logistic regression were designed to evaluate the role of UCPCR in CAD adjusted for well-known risk factors and mediators.. Median level of UCPCR was higher in CAD group compared to non-CAD group (0.07 vs. 0.04, respectively). Also, the well-acknowledged risk factors including being active smoker, hypertension, duration of diabetes, and body mass index (BMI) as well as higher levels of haemoglobin A1C (HbA1C), total cholesterol (TC), low-density lipoprotein (LDL) and estimated glomeruli filtration rate (e-GFR) had more significant pervasiveness in CAD patients. Based on multiple adjustments by logistic regression, UCPCR was a strong risk factor of CAD among T1DM patients independent of hypertension, demographic variables (gender, age, smoking, alcohol consumption), diabetes-related factors (diabetes duration, FBS, HbA1C), lipid profile (TC, LDL, HDL, TG) and renal-related indicators (creatinine, e-GFR, albuminuria, uric acid) in both patients with BMI≥30 and BMI < 30.. UCPCR is associated with clinical CAD, independent of CAD classic risk factors, glycaemic control, insulin resistance and BMI in type 1 DM patients. Topics: C-Peptide; Coronary Artery Disease; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; Hypertension | 2023 |
Effect of Tight Glycemic Control on Pancreatic Beta Cell Function in Newly Diagnosed Pediatric Type 1 Diabetes: A Randomized Clinical Trial.
Near normalization of glucose levels instituted immediately after diagnosis of type 1 diabetes has been postulated to preserve pancreatic beta cell function by reducing glucotoxicity. Previous studies have been hampered by an inability to achieve tight glycemic goals.. To determine the effectiveness of intensive diabetes management to achieve near normalization of glucose levels on preservation of pancreatic beta cell function in youth with newly diagnosed type 1 diabetes.. This randomized, double-blind, clinical trial was conducted at 6 centers in the US (randomizations from July 20, 2020, to October 13, 2021; follow-up completed September 15, 2022) and included youths with newly diagnosed type 1 diabetes aged 7 to 17 years.. Random assignment to intensive diabetes management, which included use of an automated insulin delivery system (n = 61), or standard care, which included use of a continuous glucose monitor (n = 52), as part of a factorial design in which participants weighing 30 kg or more also were assigned to receive either oral verapamil or placebo.. The primary outcome was mixed-meal tolerance test-stimulated C-peptide area under the curve (a measure of pancreatic beta cell function) 52 weeks from diagnosis.. Among 113 participants (mean [SD] age, 11.8 [2.8] years; 49 females [43%]; mean [SD] time from diagnosis to randomization, 24 [5] days), 108 (96%) completed the trial. The mean C-peptide area under the curve decreased from 0.57 pmol/mL at baseline to 0.45 pmol/mL at 52 weeks in the intensive management group, and from 0.60 to 0.50 pmol/mL in the standard care group (treatment group difference, -0.01 [95% CI, -0.11 to 0.10]; P = .89). The mean time in the target range of 70 to 180 mg/dL, measured with continuous glucose monitoring, at 52 weeks was 78% in the intensive management group vs 64% in the standard care group (adjusted difference, 16% [95% CI, 10% to 22%]). One severe hypoglycemia event and 1 diabetic ketoacidosis event occurred in each group.. In youths with newly diagnosed type 1 diabetes, intensive diabetes management, which included automated insulin delivery, achieved excellent glucose control but did not affect the decline in pancreatic C-peptide secretion at 52 weeks.. ClinicalTrials.gov Identifier: NCT04233034. Topics: Adolescent; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Glycated Hemoglobin; Glycemic Control; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells | 2023 |
Effect of Verapamil on Pancreatic Beta Cell Function in Newly Diagnosed Pediatric Type 1 Diabetes: A Randomized Clinical Trial.
In preclinical studies, thioredoxin-interacting protein overexpression induces pancreatic beta cell apoptosis and is involved in glucotoxicity-induced beta cell death. Calcium channel blockers reduce these effects and may be beneficial to beta cell preservation in type 1 diabetes.. To determine the effect of verapamil on pancreatic beta cell function in children and adolescents with newly diagnosed type 1 diabetes.. This double-blind, randomized clinical trial including children and adolescents aged 7 to 17 years with newly diagnosed type 1 diabetes who weighed 30 kg or greater was conducted at 6 centers in the US (randomized participants between July 20, 2020, and October 13, 2021) and follow-up was completed on September 15, 2022.. Participants were randomly assigned 1:1 to once-daily oral verapamil (n = 47) or placebo (n = 41) as part of a factorial design in which participants also were assigned to receive either intensive diabetes management or standard diabetes care.. The primary outcome was area under the curve values for C-peptide level (a measure of pancreatic beta cell function) stimulated by a mixed-meal tolerance test at 52 weeks from diagnosis of type 1 diabetes.. Among 88 participants (mean age, 12.7 [SD, 2.4] years; 36 were female [41%]; and the mean time from diagnosis to randomization was 24 [SD, 4] days), 83 (94%) completed the trial. In the verapamil group, the mean C-peptide area under the curve was 0.66 pmol/mL at baseline and 0.65 pmol/mL at 52 weeks compared with 0.60 pmol/mL at baseline and 0.44 pmol/mL at 52 weeks in the placebo group (adjusted between-group difference, 0.14 pmol/mL [95% CI, 0.01 to 0.27 pmol/mL]; P = .04). This equates to a 30% higher C-peptide level at 52 weeks with verapamil. The percentage of participants with a 52-week peak C-peptide level of 0.2 pmol/mL or greater was 95% (41 of 43 participants) in the verapamil group vs 71% (27 of 38 participants) in the placebo group. At 52 weeks, hemoglobin A1c was 6.6% in the verapamil group vs 6.9% in the placebo group (adjusted between-group difference, -0.3% [95% CI, -1.0% to 0.4%]). Eight participants (17%) in the verapamil group and 8 participants (20%) in the placebo group had a nonserious adverse event considered to be related to treatment.. In children and adolescents with newly diagnosed type 1 diabetes, verapamil partially preserved stimulated C-peptide secretion at 52 weeks from diagnosis compared with placebo. Further studies are needed to determine the longitudinal durability of C-peptide improvement and the optimal length of therapy.. ClinicalTrials.gov Identifier: NCT04233034. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Double-Blind Method; Female; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Male; Verapamil | 2023 |
Phenotypes Associated With Zones Defined by Area Under the Curve Glucose and C-peptide in a Population With Islet Autoantibodies.
Metabolic zones were developed to characterize heterogeneity of individuals with islet autoantibodies.. Baseline 2-h oral glucose tolerance test data from 6,620 TrialNet Pathway to Prevention Study (TNPTP) autoantibody-positive participants (relatives of individuals with type 1 diabetes) were used to form 25 zones from five area under the curve glucose (AUCGLU) rows and five area under the curve C-peptide (AUCPEP) columns. Zone phenotypes were developed from demographic, metabolic, autoantibody, HLA, and risk data.. As AUCGLU increased, changes of glucose and C-peptide response curves (from mean glucose and mean C-peptide values at 30, 60, 90, and 120 min) were similar within the five AUCPEP columns. Among the zones, 5-year risk for type 1 diabetes was highly correlated with islet antigen 2 antibody prevalence (r = 0.96, P < 0.001). Disease risk decreased markedly in the highest AUCGLU row as AUCPEP increased (0.88-0.41; P < 0.001 from lowest AUCPEP column to highest AUCPEP column). AUCGLU correlated appreciably less with Index60 (an indicator of insulin secretion) in the highest AUCPEP column (r = 0.33) than in other columns (r ≥ 0.78). AUCGLU was positively related to "fasting glucose × fasting insulin" and to "fasting glucose × fasting C-peptide" (indicators of insulin resistance) before and after adjustments for Index60 (P < 0.001).. Phenotypes of 25 zones formed from AUCGLU and AUCPEP were used to gain insights into type 1 diabetes heterogeneity. Zones were used to examine GCRC changes with increasing AUCGLU, associations between risk and autoantibody prevalence, the dependence of glucose as a predictor of risk according to C-peptide, and glucose heterogeneity from contributions of insulin secretion and insulin resistance. Topics: Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Humans; Insulin; Insulin Resistance; Phenotype | 2023 |
Non-invasive imaging of functional pancreatic islet beta-cell mass in people with type 1 diabetes mellitus.
To investigate whether manganese-enhanced magnetic resonance imaging can assess functional pancreatic beta-cell mass in people with type 1 diabetes mellitus.. In a prospective case-control study, 20 people with type 1 diabetes mellitus (10 with low (≥50 pmol/L) and 10 with very low (<50 pmol/L) C-peptide concentrations) and 15 healthy volunteers underwent manganese-enhanced magnetic resonance imaging of the pancreas following an oral glucose load. Scan-rescan reproducibility was performed in 10 participants.. Mean pancreatic manganese uptake was 31 ± 6 mL/100 g of tissue/min in healthy volunteers (median 32 [interquartile range 23-36] years, 6 women), falling to 23 ± 4 and 13 ± 5 mL/100 g of tissue/min (p ≤ 0.002 for both) in people with type1 diabetes mellitus (52 [44-61] years, 6 women) and low or very low plasma C-peptide concentrations respectively. Pancreatic manganese uptake correlated strongly with plasma C-peptide concentrations in people with type1 diabetes mellitus (r = 0.73, p < 0.001) but not in healthy volunteers (r = -0.054, p = 0.880). There were no statistically significant correlations between manganese uptake and age, body-mass index, or glycated haemoglobin. There was strong intra-observer (mean difference: 0.31 (limits of agreement -1.42 to 2.05) mL/100 g of tissue/min; intra-class correlation, ICC = 0.99), inter-observer (-1.23 (-5.74 to 3.27) mL/100 g of tissue/min; ICC = 0.85) and scan-rescan (-0.72 (-2.9 to 1.6) mL/100 g of tissue/min; ICC = 0.96) agreement for pancreatic manganese uptake.. Manganese-enhanced magnetic resonance imaging provides a potential reproducible non-invasive measure of functional beta-cell mass in people with type 1 diabetes mellitus. This holds major promise for investigating type 1 diabetes, monitoring disease progression and assessing novel immunomodulatory interventions. Topics: C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin-Secreting Cells; Manganese; Reproducibility of Results | 2023 |
The differentiation and generation of glucose-sensitive beta like-cells from menstrual blood-derived stem cells using an optimized differentiation medium with platelet-rich plasma (PRP).
Regarding their reversible damage of insulin-producing cells (IPCs) and the inefficiency of treatment methods for type 1 diabetes mellitus (T1DM), scientists decided to produce IPCs from an unlimited source of cells. But the production of these cells is constantly faced with problems such as low differentiation efficiency in cell therapy and regenerative medicine. This study provided an ideal differentiation medium enriched with plasma-rich platelet (PRP) delivery to produce IPCs from menstrual blood-derived stem cells (MenSCs). We compared them with and without PRP differentiation medium. MenSCs were then cultured in two experimental groups: with/without PRP differentiation medium and a control group (undifferentiated MenSCs). After 18 days, differentiated cells were analyzed for expression of pancreatic gene markers by real-time PCR. Immunocytochemical staining was used to detect the presence of insulin and Pdx-1 in the differentiated cells, and insulin and C-peptide secretion response to glucose were tested by ELISA. Finally, the morphology of differentiated cells was examined by an inverted microscope. In vitro studies showed that MenSCs differentiated in the PRP differentiation medium had strong properties of IPCs such as pancreatic islet-like structure. The expression of pancreatic markers at both RNA and protein levels showed that the differentiation efficiency was higher in the PRP differentiation medium. In both experimental groups, the differentiated cells were functional and secreted C-peptide and insulin on glucose stimulation, but the secretion of C-peptide and insulin in the PRP group was higher than those cultured in the without PRP differentiation medium. Our findings showed that using of PRP enriched differentiation medium can promote the differentiation of MenSCs into IPCs compared to the without PRP culture group. Therefore, the use of PRP into differentiation media can be proposed as a new approach to producing IPCs from MenSCs and used in cell-based therapies for T1DM. Topics: C-Peptide; Cell Differentiation; Diabetes Mellitus, Type 1; Glucose; Humans; Insulin; Insulin-Secreting Cells; Platelet-Rich Plasma; Stem Cells | 2023 |
Differential Associations of GAD Antibodies (GADA) and C-Peptide With Insulin Initiation, Glycemic Responses, and Severe Hypoglycemia in Patients Diagnosed With Type 2 Diabetes.
We examined the associations of GAD antibodies (GADA) and C-peptide (CP) with insulin initiation, glycemic responses, and severe hypoglycemia in type 2 diabetes (T2D).. In 5,230 Chinese patients (47.6% men) with T2D (mean ± SD age: 56.5 ± 13.9 years; median diabetes duration: 6 [interquartile range 1, 12] years), enrolled consecutively in 1996-2012 and prospectively observed until 2019, we retrospectively measured fasting CP and GADA in stored serum and examined their associations with aforementioned outcomes.. At baseline, 28.6% (n = 1,494) had low CP (<200 pmol/L) and 4.9% (n = 257) had positive GADA (GADA+). In the low-CP group, 8.0% had GADA+, and, in the GADA+ group, 46.3% had low CP. The GADA+ group had an adjusted hazard ratio (aHR) of 1.46 (95% CI 1.15-1.84, P = 0.002) for insulin initiation versus the GADA- group, while the low-CP group had an aHR of 0.88 (0.77-1.00, P = 0.051) versus the high-CP group. Following insulin initiation, the GADA+ plus low-CP group had the largest decrements in HbA1c (-1.9% at month 6; -1.5% at month 12 vs. -1% in the other three groups). The aHR of severe hypoglycemia was 1.29 (95% CI 1.10-1.52, P = 0.002) in the low-CP group and 1.38 (95% CI 1.04-1.83, P = 0.024) in the GADA+ group.. There is considerable heterogeneity in autoimmunity and β-cell dysfunction in T2D with GADA+ and high CP associated with early insulin initiation, while GADA+ and low CP, increased the risk of severe hypoglycemia. Extended phenotyping is warranted to increase the precision of classification and treatment in T2D. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Hypoglycemia; Insulin; Insulin, Regular, Human; Male; Middle Aged; Retrospective Studies | 2023 |
Excessive BMI is associated with higher C-peptide level at recognition but also with its greater loss in two years clinical observation in children with new onset type 1 diabetes.
The prevalence of obesity in general pediatric population increases without sparing children with T1D. We intended to find factors associated with the possibility of preserving endogenous insulin secretion in individuals with long-standing T1D. At onset, higher BMI is associated with higher C-peptide level, which may indicate to be one of the favorable factors involved in preserving residual β-cell function. The study determines the influence of BMI on C-peptide secretion in children newly diagnosed with T1D in two years observation.. We assessed the possible relationship between selected pro- and anti-inflammatory cytokines, body mass at recognition and β-cell function status. 153 pediatric patients with newly diagnosed T1D were divided into quartiles according to BMI-SDS index. We separated a group consisted of patients with BMI-SDS >1. Participants were followed up for two years and examined for changes in body weight, HbA1c, and insulin requirement. C-peptide was assessed at baseline and after two years. We evaluated the patients' levels of selected inflammatory cytokines at baseline.. Subjects with higher BMI-SDS presented higher serum C-peptide levels and lower insulin requirements at diagnosis than children with lower body weight. The two-year follow-up showed that C-peptide levels of obese patients dropped more rapidly than in children with BMI-SDS within normal limits. The group with BMI-SDS >1 showed the greatest decrease in C-peptide level. Despite statistically insignificant differences in HbA1c at diagnosis between the study groups, in the fourth quartile and BMI-SDS >1 groups, HbA1c as well as insulin requirements increased after two years. The levels of cytokines varied the most between BMI-SDS <1 and BMI-SDS >1 groups and were significantly higher within BMI-SDS >1 group.. Higher BMI, associated with enhanced levels of inflammatory cytokines, relates to preservation of C-peptide at T1D recognition in children but is not beneficial in the long term. A decrease in C-peptide levels combined with an increase in insulin requirements and in HbA1c among patients with high BMI occur, which may indicate a negative effect of excessive body weight on the long term preservation of residual β-cell function. The process seems to be mediated by inflammatory cytokines. Topics: Body Mass Index; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Obesity; Weight Gain | 2023 |
Beta cell function in the early stages of type 1 diabetes: still a long way ahead of us.
The clinical onset of type 1 diabetes (namely stage 3 type 1 diabetes [T1D]) is preceded by a relatively prolonged pre-symptomatic phase featured by islet autoimmunity [1] with (Stage 2 T1D) or without (Stage 1 T1D) dysglycaemia. While islet autoimmunity is the hallmark of the underlying autoimmune process, very little evidence is available for the metabolic changes that accompany the loss of functional beta cell mass. Indeed, a steep decline of C-peptide - a surrogate marker of beta cell function - is measurable only ~6 months before the onset of Stage 3 T1D [2]. Disease modifier drugs have, there-fore, a very limited window of intervention because we lack of effective methods to track beta cell function over time and to identify early changes of insulin secretion that precedes dysglycaemia [3, 4] and clinically symptomatic diabetes. Herein, we will revise current approaches to longitudinally track beta cell function over time before the onset of Stage 3 T1D, which might be suitable for monitoring the risk for diabetes progression as well as the effectiveness of disease modifier treatments. Topics: Autoimmunity; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin Secretion; Insulin-Secreting Cells | 2023 |
Residual insulin secretion in individuals with type 1 diabetes in Finland: longitudinal and cross-sectional analyses.
Contrary to the presumption that type 1 diabetes leads to an absolute insulin deficiency, many individuals with type 1 diabetes have circulating C-peptide years after the diagnosis. We studied factors affecting random serum C-peptide concentration in individuals with type 1 diabetes and the association with diabetic complications.. Our longitudinal analysis included individuals newly diagnosed with type 1 diabetes from Helsinki University Hospital (Helsinki, Finland) with repeated random serum C-peptide and concomitant glucose measurements from within 3 months of diagnosis and at least once later. The long-term cross-sectional analysis included data from participants from 57 centres in Finland who had type 1 diabetes diagnosed after 5 years of age, initiation of insulin treatment within 1 year from diagnosis, and a C-peptide concentration of less than 1·0 nmol/L (FinnDiane study) and patients with type 1 diabetes from the DIREVA study. We tested the association of random serum C-peptide concentrations and polygenic risk scores with one-way ANOVA, and association of random serum C-peptide concentrations, polygenic risk scores, and clinical factors with logistic regression.. The longitudinal analysis included 847 participants younger than 16 years and 110 aged 16 years or older. In the longitudinal analysis, age at diagnosis strongly correlated with the decline in C-peptide secretion. The cross-sectional analysis included 3984 participants from FinnDiane and 645 from DIREVA. In the cross-sectional analysis, at a median duration of 21·6 years (IQR 12·5-31·2), 776 (19·4%) of 3984 FinnDiane participants had residual random serum C-peptide secretion (>0·02 nmol/L), which was associated with lower type 1 diabetes polygenic risk compared with participants without random serum C-peptide (p<0·0001). Random serum C-peptide was inversely associated with hypertension, HbA. Although children with multiple autoantibodies and HLA risk genotypes progressed to absolute insulin deficiency rapidly, many adolescents and adults had residual random serum C-peptide decades after the diagnosis. Polygenic risk of type 1 and type 2 diabetes affected residual random serum C-peptide. Even low residual random serum C-peptide concentrations seemed to be associated with a beneficial complications profile.. Folkhälsan Research Foundation; Academy of Finland; University of Helsinki and Helsinki University Hospital; Medical Society of Finland; the Sigrid Juselius Foundation; the "Liv and Hälsa" Society; Novo Nordisk Foundation; and State Research Funding via the Helsinki University Hospital, the Vasa Hospital District, Turku University Hospital, Vasa Central Hospital, Jakobstadsnejdens Heart Foundation, and the Medical Foundation of Vaasa. Topics: Adolescent; Adult; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Finland; Humans; Insulin; Insulin Secretion | 2023 |
Efficacy of combination therapy with GABA, a DPP-4i and a PPI as an adjunct to insulin therapy in patients with type 1 diabetes.
The purpose of this retrospective clinic chart review study was to determine the potential of a combination therapy (CT) consisting of γ-aminobutyric acid (GABA), a dipeptidyl peptidase-4 inhibitor (DPP-4i), and a proton pump inhibitor (PPI) to improve glycemic control as an adjunct to insulin therapy in patients with type 1 diabetes (T1D).. Nineteen patients with T1D on insulin therapy were treated with additional CT in oral form. Fasting blood glucose (FBG), HbA1c, insulin dose-adjusted HbA1c (IDA-A1c), daily insulin dose, insulin/weight ratio (IWR), and fasting plasma C-peptide were measured after 26-42 weeks of treatments.. FBG, HbA1c, IDA-A1c, insulin dose and IWR were all significantly decreased while plasma C-peptide was significantly increased by the CT. Treatment outcomes were further analyzed by separation of the 19 patients into two groups. One group started on the CT within 12 months of insulin treatment (early therapy, 10 patients) and another group started on this therapy only after 12 months of insulin treatment (late therapy, 9 patients). FBG, IDA-A1c, insulin dose, and IWR decreased significantly in both the early and late CT groups, however to a better extent in the early therapy group. Moreover, plasma C-peptide increased significantly only in the early therapy group, and 7 of the 10 patients in this group were able to discontinue insulin treatment while maintaining good glycemic control to study end compared with none of the 9 patients in the late therapy group.. These results support the concept that the combination of GABA, a DPP-4i and a PPI as an adjunct to insulin therapy improves glycemic control in patients with T1D, and that the insulin dose required for glycemic control can be reduced or even eliminated in some patients receiving this novel therapy. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; gamma-Aminobutyric Acid; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Proton Pump Inhibitors; Retrospective Studies | 2023 |
Insulin Secretion Capacity as a Crucial Feature to Distinguish Type 1 From Type 2 Diabetes and to Indicate the Need for Insulin Therapy - A Critical Discussion of the ADA/EASD Consensus Statement on the Management of Type 1 Diabetes in Adults.
In the recently published consensus statement on the treatment and management of type 1 diabetes issued by experts from the American (ADA) and European (EASD) diabetes societies, measurement of endogenous insulin secretion using fasting C-peptide is recommended as a diagnostic criterion. In contrast, our group recently suggested fasting C-peptide/glucose ratio (CGR) for the determination of endogenous insulin secretion. In addition, this ratio may turn out as a potential decision aid for pathophysiologically based differential therapy of diabetes. In this comment, the following points will be discussed: i) CGR as the basis of differential diagnosis of type 1 diabetes, ii) CGR as the basis of treatment decisions for or against insulin in diabetes, and iii) the ease of application of CGR in clinical practice. The use of CGR may complement the ADA/EASD recommendations and should provide a practical application in clinical practice. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; United States | 2023 |
Prevalence, clinical characteristics and HLA genotypes of idiopathic type 1 diabetes: A cross-sectional study.
Idiopathic type 1 diabetes (T1D) is a neglected subtype of T1D. Our aim was to investigate the frequency, clinical characteristics, and human leucocyte antigen (HLA) genotypes of idiopathic T1D.. We enrolled 1205 newly diagnosed T1D patients in our analysis. To exclude monogenic diabetes in autoantibody-negative patients, we utilised a custom monogenic diabetes gene panel. Individuals negative for autoantibodies and subsequently excluded for monogenic diabetes were diagnosed with idiopathic T1D. We collected clinical characteristics, measured islet autoantibodies by radioligand assay and obtained HLA data.. After excluding 11 patients with monogenic diabetes, 284 cases were diagnosed with idiopathic T1D, accounting for 23.8% (284/1194) of all newly diagnosed T1D cases. When compared with autoimmune T1D, idiopathic T1D patients showed an older onset age, higher body mass index among adults, lower haemoglobin A1c, higher levels of fasting C-peptide and 2-h postprandial C-peptide, and were likely to have type 2 diabetes (T2D) family history and carry 0 susceptible HLA haplotype (all p < 0.01). A lower proportion of individuals carrying 2 susceptible HLA haplotypes in idiopathic T1D was observed in the adult-onset subgroup (15.7% vs. 38.0% in child-onset subgroup, p < 0.001) and in subgroup with preserved beta-cell function (11.0% vs. 30.1% in subgroup with poor beta-cell function, p < 0.001). Multivariable correlation analyses indicated that being overweight, having T2D family history and lacking susceptible HLA haplotypes were associated with negative autoantibodies.. Idiopathic T1D represents about 1/4 of newly diagnosed T1D, with adult-onset and preserved beta-cell function patients showing lower HLA susceptibility and more insulin resistance. Topics: Adult; Autoantibodies; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Genotype; HLA Antigens; Humans; Prevalence | 2023 |
Responders to low-dose ATG induce CD4+ T cell exhaustion in type 1 diabetes.
BACKGROUNDLow-dose anti-thymocyte globulin (ATG) transiently preserves C-peptide and lowers HbA1c in individuals with recent-onset type 1 diabetes (T1D); however, the mechanisms of action and features of the response remain unclear. Here, we characterized the post hoc immunological outcomes of ATG administration and their potential use as biomarkers of metabolic response to therapy (i.e., improved preservation of endogenous insulin production).METHODSWe assessed gene and protein expression, targeted gene methylation, and cytokine concentrations in peripheral blood following treatment with ATG (n = 29), ATG plus granulocyte colony-stimulating factor (ATG/G-CSF, n = 28), or placebo (n = 31).RESULTSTreatment with low-dose ATG preserved regulatory T cells (Tregs), as measured by stable methylation of FOXP3 Treg-specific demethylation region (TSDR) and increased proportions of CD4+FOXP3+ Tregs (P < 0.001) identified by flow cytometry. While treatment effects were consistent across participants, not all maintained C-peptide. Responders exhibited a transient rise in IL-6, IP-10, and TNF-α (P < 0.05 for all) 2 weeks after treatment and a durable CD4+ exhaustion phenotype (increased PD-1+KLRG1+CD57- on CD4+ T cells [P = 0.011] and PD1+CD4+ Temra MFI [P < 0.001] at 12 weeks, following ATG and ATG/G-CSF, respectively). ATG nonresponders displayed higher proportions of senescent T cells (at baseline and after treatment) and increased methylation of EOMES (i.e., less expression of this exhaustion marker).CONCLUSIONAltogether in these exploratory analyses, Th1 inflammation-associated serum and CD4+ exhaustion transcript and cellular phenotyping profiles may be useful for identifying signatures of clinical response to ATG in T1D.TRIAL REGISTRATIONClinicalTrials.gov NCT02215200.FUNDINGThe Leona M. and Harry B. Helmsley Charitable Trust (2019PG-T1D011), the NIH (R01 DK106191 Supplement, K08 DK128628), NIH TrialNet (U01 DK085461), and the NIH NIAID (P01 AI042288). Topics: Antilymphocyte Serum; C-Peptide; CD4-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Forkhead Transcription Factors; Granulocyte Colony-Stimulating Factor; Humans; T-Cell Exhaustion | 2023 |
Identification of appropriate biochemical parameters and cut points to detect Maturity Onset Diabetes of Young (MODY) in Asian Indians in a clinic setting.
Topics: Adolescent; C-Peptide; Cholesterol, HDL; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; India; Mutation | 2023 |
Assessment Of Serum Vitamin D Level In Children With Type 1 Diabetes Mellitus: A Cross-Sectional Study.
To estimate vitamin D levelsin children with type 1 diabetes, and to evaluate itsrole in the pathogenesis and progress of the disease.. The cross-sectional study was conducted at the Paediatric Department of Kafrelsheikh University Hospital, Egypt, from November 2019 to August 2021, and comprised children of either gender aged 3-18 years who were either inpatients or visiting the paediatric outpatient clinic. The subjects were enrolled into 3 groups. Those with newly diagnosed type 1 diabetes were in group A, those with established type 1 diabetes were in group B, and healthy children matched for age and gender and randomly selected were in the control group C. Glycated haemoglobin, serum fasting C-peptide, and serum vitamin D levels were evaluated using quantitative colorimetric determination, an automated analyser, and enzyme-linked immunosorbent assay, respectively. Data was analysed using SPSS 25.. Of the 80 subjects, 30(37.5%) were in group A; 17(56.7%) boys and 13(43.3%) girls with mean age 7.77±2.95 years. In group B, there were 30(37.5%) subjects; 14(46.7%) boys and 16(53.3%) girls with mean age 9.6±3.62 years. There were 20(25%) subjects in group C; 10(50%) boys and as many girls with mean age 8.38±2.68 years (p>0.05). Glycated haemoglobin,serum fasting C-peptide and serum vitamin D wassignificantly different between the control group and the treatment groups (p<0.05). Between the treatment groups, group B had better markers than group A (p<0.05).. Serum vitamin D deficiency may play a role in the pathogenesis and insulin sensitivity in cases of type 1 diabetes. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Male; Vitamin D; Vitamin D Deficiency | 2023 |
Targeted serum proteomics of longitudinal samples from newly diagnosed youth with type 1 diabetes distinguishes markers of disease and C-peptide trajectory.
There is a growing need for markers that could help indicate the decline in beta cell function and recognise the need and efficacy of intervention in type 1 diabetes. Measurements of suitably selected serum markers could potentially provide a non-invasive and easily applicable solution to this challenge. Accordingly, we evaluated a broad panel of proteins previously associated with type 1 diabetes in serum from newly diagnosed individuals during the first year from diagnosis. To uncover associations with beta cell function, comparisons were made between these targeted proteomics measurements and changes in fasting C-peptide levels. To further distinguish proteins linked with the disease status, comparisons were made with measurements of the protein targets in age- and sex-matched autoantibody-negative unaffected family members (UFMs).. Selected reaction monitoring (SRM) mass spectrometry analyses of serum, targeting 85 type 1 diabetes-associated proteins, were made. Sera from individuals diagnosed under 18 years (n=86) were drawn within 6 weeks of diagnosis and at 3, 6 and 12 months afterwards (288 samples in total). The SRM data were compared with fasting C-peptide/glucose data, which was interpreted as a measure of beta cell function. The protein data were further compared with cross-sectional SRM measurements from UFMs (n=194).. Eleven proteins had statistically significant associations with fasting C-peptide/glucose. Of these, apolipoprotein L1 and glutathione peroxidase 3 (GPX3) displayed the strongest positive and inverse associations, respectively. Changes in GPX3 levels during the first year after diagnosis indicated future fasting C-peptide/glucose levels. In addition, differences in the levels of 13 proteins were observed between the individuals with type 1 diabetes and the matched UFMs. These included GPX3, transthyretin, prothrombin, apolipoprotein C1 and members of the IGF family.. The association of several targeted proteins with fasting C-peptide/glucose levels in the first year after diagnosis suggests their connection with the underlying changes accompanying alterations in beta cell function in type 1 diabetes. Moreover, the direction of change in GPX3 during the first year was indicative of subsequent fasting C-peptide/glucose levels, and supports further investigation of this and other serum protein measurements in future studies of beta cell function in type 1 diabetes. Topics: Adolescent; Blood Glucose; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Glucose; Humans; Insulin; Proteomics | 2023 |
Teplizumab: A Disease-Modifying Therapy for Type 1 Diabetes That Preserves β-Cell Function.
In November 2022, teplizumab-mzwv became the first drug approved to delay the onset of stage 3 type 1 diabetes in adults and children age ≥8 years with stage 2 type 1 diabetes on the basis of data from the pivotal study TN-10.. To provide confirmatory evidence of the effects of teplizumab on preserving endogenous insulin production, an integrated analysis of C-peptide data from 609 patients (n = 375 patients receiving teplizumab and n = 234 control patients) from five clinical trials in stage 3 type 1 diabetes was conducted.. The primary outcome of the integrated analysis, change from baseline in stimulated C-peptide, was significantly improved at years 1 (average increase 0.08 nmol/L; P < 0.0001) and 2 (average increase 0.12 nmol/L; P < 0.0001) after one or two courses of teplizumab. An analysis of exogenous insulin use was also conducted, showing overall reductions of 0.08 (P = 0.0001) and 0.10 units/kg/day (P < 0.0001) at years 1 and 2, respectively. An integrated safety analysis of five clinical trials that enrolled 1,018 patients with stage 2 or 3 type 1 diabetes (∼1,500 patient-years of follow-up for teplizumab-treated patients) was conducted.. These data confirm consistency in the preservation of β-cell function, as measured by C-peptide, across multiple clinical trials. This analysis showed that the most common adverse events included lymphopenia, rash, and headache, a majority of which occurred during and after the first few weeks of teplizumab administration and generally resolved without intervention, consistent with a safety profile characterized by self-limited adverse events after one or two courses of teplizumab treatment. Topics: Adult; Antibodies, Monoclonal, Humanized; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin, Regular, Human | 2023 |
The relationship between red blood cell distribution width and islet β-cell function indexes in patients with latent autoimmune diabetes in adults.
The objective of this study is to explore the relationship between red blood cell distribution and islet β-cell function indexes in patients with Latent Autoimmune Diabetes in Adults.. A total of 487 LADA patients were enrolled in this cross-sectional study. Patients were divided into three groups according to RDW tertiles. Clinical and laboratory measurements of age, height, weight, duration of diabetes, blood pressure, RDW, glycosylated hemoglobin A1c (HbA1c), C-peptide and blood lipids were performed. Homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β) were assessed using homeostasis model assessment (HOMA) based on fasting blood glucose (FBG) and fasting C-peptide index (FCP). Correlations and multiple linear regressions were implemented to determine the association of RDW and islet function indexes.. As the increase of serum RDW level, the presence of β-cell secretion increased(P < 0.05). Correlation analysis indicated that there were significant correlations between RDW and male sex, age, duration, TG, Cr, FCP, and HOMA-β in all subjects. Multiple linear regressions indicated that RDW was significantly correlated with HOMA-β in the total population in both unadjusted and adjusted analysis. This finding could be reproduced in the subgroup of low GAD titers for HOMA-β. RDW were significantly associated with HbA1c in LADA patients with high GAD titers, but the correlation was not found in subgroup with low GAD titers in either unadjusted analyses or adjusted analysis.. RDW is associated with β-cell function assessed by HOMA-β after adjusting for covariates in LADA patients with low GAD titers. Topics: Adult; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Erythrocytes; Glucose Intolerance; Glycated Hemoglobin; Humans; Latent Autoimmune Diabetes in Adults; Male | 2023 |
High proinsulin:C-peptide ratio identifies individuals with stage 2 type 1 diabetes at high risk for progression to clinical diagnosis and responses to teplizumab treatment.
Tractable precision biomarkers to identify immunotherapy responders are lacking in type 1 diabetes. We hypothesised that proinsulin:C-peptide (PI:C) ratios, a readout of beta cell stress, could provide insight into type 1 diabetes progression and responses to immunotherapy.. In this post hoc analysis, proinsulin and C-peptide levels were determined in baseline serum samples from 63 participants with stage 2 type 1 diabetes in the longitudinal TrialNet Teplizumab Prevention Study (n=41 in the teplizumab arm; n=22 in the placebo arm). In addition, previously tested demographic, C-peptide, glucose and proinsulin data were used for the new data analyses. The ratio of intact (unprocessed) proinsulin to C-peptide was analysed and relationships with progression to stage 3 diabetes were investigated.. Elevated baseline PI:C was strongly associated with more rapid progression of diabetes in both the placebo and teplizumab treatment groups, but teplizumab abrogated the impact of high pre-treatment PI:C on type 1 diabetes progression. Differential responses of drug treatment in those with high vs low PI:C ratios were independent of treatment effects of teplizumab on the PI:C ratio or on relevant immune cells.. High pre-treatment PI:C identified individuals with stage 2 type 1 diabetes who were exhibiting rapid progression to stage 3 disease and who displayed benefit from teplizumab treatment. These data suggest that readouts of active disease, such as PI:C ratio, could serve to identify optimal candidates or timing for type 1 diabetes disease-modifying therapies. Topics: Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Proinsulin | 2023 |
Younger patients and low c-peptide immunoreactivity index but not nutritional states affect fasting blood ketone levels in Japanese with type 1 diabetes after sodium-glucose cotransporter 2 inhibitor administration.
Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are available for individuals with type 1 diabetes, but appropriate use is recommended to prevent ketosis or ketoacidosis. This study aimed to evaluate the risk of ketosis in people with type 1 diabetes, focusing on the relationship between nutritional assessment, glycaemic status, c-peptide immunoreactivity (CPR) index and body composition.. In total, 46 Japanese patients with type 1 diabetes were included, and dietary assessment from food photographs and ketone levels were evaluated before and after taking SGLT2is. The effect of diet on morning ketone levels was also investigated.. All patients had an increase in mean ketone concentrations after taking SGLT2is (before 0.12 ± 0.06 mmol/L, after 0.23 ± 0.16 mmol/L). A significant negative correlation was found between average morning ketone levels and age (r = -0.514, p < .001) and the CPR index (r = -0.523, p = .038) after taking SGLT2is. Using a mixed-effects model based on the results before starting the inhibitors, it was noted that both patient-to-patient and age, or patient-to-patient and capacity of insulin secretion, influenced the ketone levels. Multiple regression analysis showed that factors associated with the risk of increasing ketone levels after taking SGLT2is were younger age (β = -0.504, p = .003) and a low ratio of basal to bolus insulin (β = -0.420, p = .005).. When administering SGLT2is to patients with a low CPR index or younger patients with type 1 diabetes, adequate instructions to prevent ketosis should be given. Topics: C-Peptide; Diabetes Mellitus, Type 1; East Asian People; Fasting; Humans; Ketones; Ketosis; Sodium-Glucose Transporter 2 Inhibitors | 2023 |
Comparison of Visual Methods to Reanalyze Provocative Test Data from Randomized Controlled Clinical Trials in New- or Recent-Onset Type 1 Diabetes.
Over the last 13 years, the Immune Tolerance Network (ITN), has conducted trials of agents to abrogate the autoimmunity underlying type 1 diabetes. Primary endpoints center on the change of C-peptide production during mixed meal tolerance tests (MMTT), measured as the area under the curve (AUC) or AUC mean over 2-3 years. Studies permit rapid-acting insulin until a few hours before the MMTT, and thus do not exclude overnight hyperglycemia prior to testing. We hypothesize that overnight or fasting hyperglycemia will deplete pre-formed insulin and impact measurements of first-phase insulin secretion and C-peptide AUC.. Publicly available, deidentified, subject-level data were obtained from ITN TrialShare. We developed several graphical analyses to reexamine results from each MMTT including combined glucose and C-peptide response curves, the centroids of polygons of MMTT timepoints, and ratios comparing extents of excursions of glucose and c-peptide production.. We have applied these graphical analyses to 1161 MMTT from 245 subjects in 8 studies. Graphical analyses of MMTT results for individuals over the course of the follow-up period reflect the expected loss of c-peptide and higher blood glucose during MMTT; centroids move accordingly, upwards and leftwards.. We were able to analyze MMTT data from ITN studies with several graphical analyses. We are poised to apply these approaches to test our central hypothesis by comparing how deviations from modeled rates of predicted changes for an individual over time correlate with blood glucose levels in the hours before a MMTT. This may lead to refinement of future trial protocols to ensure tighter regulation of glycemic excursions ahead of provocative testing. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Humans; Hyperglycemia | 2023 |
Islet-autoreactive CD4+ T cells are linked with response to alefacept in type 1 diabetes.
Variation in the preservation of β cell function in clinical trials in type 1 diabetes (T1D) has emphasized the need to define biomarkers to predict treatment response. The T1DAL trial targeted T cells with alefacept (LFA-3-Ig) and demonstrated C-peptide preservation in approximately 30% of new-onset T1D individuals. We analyzed islet antigen-reactive (IAR) CD4+ T cells in PBMC samples collected prior to treatment from alefacept- and placebo-treated individuals using flow cytometry and single-cell RNA sequencing. IAR CD4+ T cells at baseline had heterogeneous phenotypes. Transcript profiles formed phenotypic clusters of cells along a trajectory based on increasing maturation and activation, and T cell receptor (TCR) chains showed clonal expansion. Notably, the frequency of IAR CD4+ T cells with a memory phenotype and a unique transcript profile (cluster 3) were inversely correlated with C-peptide preservation in alefacept-treated, but not placebo-treated, individuals. Cluster 3 cells had a proinflammatory phenotype characterized by expression of the transcription factor BHLHE40 and the cytokines GM-CSF and TNF-α, and shared TCR chains with effector memory-like clusters. Our results suggest IAR CD4+ T cells as a potential baseline biomarker of response to therapies targeting the CD2 pathway and warrant investigation for other T cell-related therapies. Topics: Alefacept; Biomarkers; C-Peptide; CD4-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Humans; Leukocytes, Mononuclear; Receptors, Antigen, T-Cell | 2023 |
The MHC Class II Antigen-Processing and Presentation Pathway Is Dysregulated in Type 1 Diabetes.
Peptide loading of MHC class II (MHCII) molecules is facilitated by HLA-DM (DM), which catalyzes CLIP release, stabilizes empty MHCII, and edits the MHCII-bound peptide repertoire. HLA-DO (DO) binds to DM and modulates its activity, resulting in an altered set of peptides presented at the cell surface. MHCII-peptide presentation in individuals with type 1 diabetes (T1D) is abnormal, leading to a breakdown in tolerance; however, no direct measurement of the MHCII pathway activity in T1D patients has been performed. In this study, we measured MHCII Ag-processing pathway activity in humans by determining MHCII, MHCII-CLIP, DM, and DO levels by flow cytometry for peripheral blood B cells, dendritic cells, and monocytes from 99 T1D patients and 97 controls. Results showed that MHCII levels were similar for all three APC subsets. In contrast, MHCII-CLIP levels, independent of sex, age at blood draw, disease duration, and diagnosis age, were significantly increased for all three APCs, with B cells showing the largest increase (3.4-fold). DM and DO levels, which usually directly correlate with MHCII-CLIP levels, were unexpectedly identical in T1D patients and controls. Gene expression profiling on PBMC RNA showed that DMB mRNA was significantly elevated in T1D patients with residual C-peptide. This resulted in higher levels of DM protein in B cells and dendritic cells. DO levels were also increased, suggesting that the MHCII pathway maybe differentially regulated in individuals with residual C-peptide. Collectively, these studies show a dysregulation of the MHCII Ag-processing pathway in patients with T1D. Topics: Antigen Presentation; C-Peptide; Diabetes Mellitus, Type 1; Histocompatibility Antigens Class II; HLA-D Antigens; Humans; Leukocytes, Mononuclear; Peptides | 2023 |
A standardized metric to enhance clinical trial design and outcome interpretation in type 1 diabetes.
The use of a standardized outcome metric enhances clinical trial interpretation and cross-trial comparison. If a disease course is predictable, comparing modeled predictions with outcome data affords the precision and confidence needed to accelerate precision medicine. We demonstrate this approach in type 1 diabetes (T1D) trials aiming to preserve endogenous insulin secretion measured by C-peptide. C-peptide is predictable given an individual's age and baseline value; quantitative response (QR) adjusts for these variables and represents the difference between the observed and predicted outcome. Validated across 13 trials, the QR metric reduces each trial's variance and increases statistical power. As smaller studies are especially subject to random sampling variability, using QR as the outcome introduces alternative interpretations of previous clinical trial results. QR can provide model-based estimates that quantify whether individuals or groups did better or worse than expected. QR also provides a purer metric to associate with biomarker measurements. Using data from more than 1300 participants, we demonstrate the value of QR in advancing disease-modifying therapy in T1D. QR applies to any disease where outcome is predictable by pre-specified baseline covariates, rendering it useful for defining responders to therapy, comparing therapeutic efficacy, and understanding causal pathways in disease. Topics: C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Insulin Secretion; Precision Medicine | 2023 |
Circulating Hematopoietic (HSC) and Very-Small Embryonic like (VSEL) Stem Cells in Newly Diagnosed Childhood Diabetes type 1 - Novel Parameters of Beta Cell Destruction/Regeneration Balance and Possible Prognostic Factors of Future Disease Course.
We aimed to evaluate hematopoietic stem cells (HSC) and very small embryonic-like stem cells (VSEL) mobilization to establish their role in residual beta cell function maintenance and partial remission occurrence in children newly diagnosed with type 1 diabetes.. We recruited 59 type 1 diabetic patients (aged 6-18 years) monitored for 2 years, and 31 healthy children as a control group. HSC and VSEL levels were assessed at disease onset in PBMC isolated from whole peripheral blood with the use of flow cytometry. An assessment of beta cell function was based on C-peptide secretion. Studied groups were stratified on the basis of VSEL, HSC and/or C-peptide median levels in regard to beta cell function and partial remission.. Patients with higher stimulated C-peptide secretion at disease onset demonstrated lower levels of HSC (p < 0.05), while for VSEL and VSEL/HSC ratio higher values were observed (p < 0.05). Accordingly, after 2 years follow-up, patients with higher C-peptide secretion presented lower initial levels of HSC and higher VSEL/HSC ratio (p < 0.05). Patients with lower values of HSC levels demonstrated a tendency for better partial remission prevalence in the first 3 to 6 months after diagnosis.. These clinical observations indicate a possible significant role of HSC and VSEL in maintaining residual beta cell function in type 1 diabetic patients. Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Hematopoietic Stem Cells; Humans; Leukocytes, Mononuclear; Prognosis | 2022 |
Do pretransplant C-peptide levels predict outcomes following simultaneous pancreas-kidney transplantation? A matched case-control study.
Following simultaneous pancreas-kidney transplantation (SPKT), survival outcomes are reported as equivalent in patients with detectable pretransplant C-peptide levels (Cp+) and a "type 2″ diabetes mellitus (DM) phenotype compared to type 1 (Cp negative [Cp-]) DM. We retrospectively compared 46 Cp+ patients pretransplant (≥2.0 ng/mL, mean 5.4 ng/mL) to 46 Cp- (level < 0.5 ng/mL) case controls matched for recipient age, gender, race, and transplant date. Early outcomes were comparable. Actual 5-year patient survival (91% versus 94%), kidney graft survival (69% versus 86%, p = .15), and pancreas graft survival (60% versus 86%, p = .03) rates were lower in Cp+ versus Cp- patients, respectively. The Cp+ group had more pancreas graft failures due to insulin resistance (13% Cp+ versus 0% Cp-, p = .026) or rejection (17% Cp+ versus 6.5% Cp-, p = .2). Post-transplant weight gain > 5 kg occurred in 72% of Cp+ versus 26% of Cp- patients (p = .0001). In patients with functioning grafts, mean one-year post-transplant HbA1c levels (5.0 Cp+ versus 5.2% Cp-) were comparable, whereas Cp levels were higher in Cp+ patients (5.0 Cp+ versus 2.6 ng/mL Cp-). In this matched case-control study, outcomes were inferior in Cp+ compared to Cp- patients following SPKT, with post-transplant weight gain, insulin resistance, and rejection as potential mitigating factors. Topics: C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Graft Survival; Humans; Kidney Transplantation; Pancreas; Pancreas Transplantation; Retrospective Studies | 2022 |
Association between physical activity before diagnosis and the presence of clinical remission in type 1 diabetes - InlipoDiab1 study.
To investigate whether physical activity is associated with the occurrence of remission in adults with type 1 diabetes.. Ninety nine adult participants with newly diagnosed type 1 diabetes were enroled into a prospective, observational study. The participants were advised to exercise 2-3 times a week with moderate intensity for a one-year period. Physical activity was assessed by a self-administrated questionnaire on every fourth visit. We counted the months in which participants fulfiled a partial-remission criteria: HbA1c < 6.5%, C-peptide > 0.5 ng/ml, and daily dose of insulin <0.3 U/kg/day. We assigned the participants to two groups: MORE EFFORT and LESS EFFORT, depending on the median value of physical activity in the studied population.. The occurrence of the remission achieved statistical significance at 6th month with a greater prevalence in MORE EFFORT group (55% vs. 35% p = 0.047). In multivariate logistic regression analysis for the occurrence of remission at 12th month, physical activity before the diagnosis was the only variable that influences the occurrence of the remission (adjusted odds ratios = 3.32 [95% confidence intervals 1.25-8.80]; p = 0.02).. In adults with newly diagnosed type 1 diabetes physical activity before the diagnosis is associated with higher occurrence of remission. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Exercise; Humans; Insulin; Prospective Studies; Remission Induction | 2022 |
Index60 Identifies Individuals at Appreciable Risk for Stage 3 Among an Autoantibody-Positive Population With Normal 2-Hour Glucose Levels: Implications for Current Staging Criteria of Type 1 Diabetes.
We assessed whether Index60, a composite measure of fasting C-peptide, 60-min C-peptide, and 60-min glucose, could improve the metabolic staging of type 1 diabetes for progression to clinical disease (stage 3) among autoantibody-positive (Ab+) individuals with normal 2-h glucose values (<140 mg/dL).. We analyzed 3,058 Type 1 Diabetes TrialNet Pathway to Prevention participants with 2-h glucose <140 mg/dL and Index60 <1.00 values from baseline oral glucose tolerance tests. Characteristics associated with type 1 diabetes (younger age, greater Ab+, higher HLA DR3-DQ2/DR4-DQ8 prevalence, and lower C-peptide) were compared among four mutually exclusive groups: top 2-h glucose quartile only (HI-2HGLU), top Index60 quartile only (HI-IND60), both top quartiles (HI-BOTH), and neither top quartile (LO-BOTH). Additionally, within the 2-h glucose distribution of <140 mg/dL and separately within the Index60 <1.00 distribution, comparisons were made between those above or below the medians.. HI-IND60 and HI-BOTH were younger, with greater frequency of more than two Ab+, and lower C-peptide levels, than either HI-2HGLU or LO-BOTH (all P < 0.001). The cumulative incidence for stage 3 was greater for HI-IND60 and HI-BOTH than for either HI-2HGLU or LO-BOTH (all P < 0.001). Those with Index60 values above the median were younger and had higher frequency of two or more Ab+ (P < 0.001) and DR3-DQ2/DR4-DQ8 prevalence (P < 0.001) and lower area under the curve (AUC) C-peptide levels (P < 0.001) than those below. Those above the 2-h glucose median had higher AUC C-peptide levels (P < 0.001), but otherwise did not differ from those below.. Index60 identifies individuals with characteristics of type 1 diabetes at appreciable risk for progression who would otherwise be missed by 2-h glucose staging criteria. Topics: Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Glucose Tolerance Test; Humans | 2022 |
How low is really low? Comparison of two C-peptide assays to establish residual C-peptide production in type 1 diabetes.
C-peptide is an important marker to assess residual insulin production in individuals with type 1 diabetes (T1D). The accuracy and detection limits of C-peptide assays are important to detect C-peptide microsecretion and to reliably observe changes over time in these people. We compared and verified two commercially available assays able to measure C-peptide in the picomolar range.. The ultrasensitive Mercodia enzyme-linked immunosorbent C-peptide assay (ELISA) was compared with the Beckman immunoradiometric assay (IRMA) for C-peptide, assessing reproducibility (coefficient of variation [CV]), limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ).. For both assays within-run and between-run variation were high at the low (around the detection limit) C-peptide concentration range, with CVs of around 40%. LoB values for the ultrasensitive ELISA and the IRMA were 1.3 and 0.16 pmol/L respectively. LoD values were 2.4 and 0.54 pmol/L respectively. LoQ values were 9.7 and 3.8 pmol/L respectively. Only the IRMA met the specifications claimed by the manufacturer.. The IRMA provided the lowest threshold for quantification of serum C-peptide. LoQ of commercially available assays should be established in-house before applying them in research studies and clinical trials in which low C-peptide levels have clinical or scientific relevance. Topics: Biological Assay; C-Peptide; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Humans; Insulin; Reproducibility of Results | 2022 |
Comment on Meek et al. Reappearance of C-Peptide During the Third Trimester of Pregnancy in Type 1 Diabetes: Pancreatic Regeneration or Fetal Hyperinsulinism? Diabetes Care 2021;44:1826-1834.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hyperinsulinism; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Third; Regeneration | 2022 |
Response to Comment on Meek et al. Reappearance of C-Peptide During the Third Trimester in Type 1 Diabetes Pregnancy: Pancreatic Regeneration or Fetal Hyperinsulinism? Diabetes Care 2021;44:1826-1834.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hyperinsulinism; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Third; Regeneration | 2022 |
High Residual β-cell Function in Chinese Patients With Autoimmune Type 1 Diabetes.
The destruction of pancreatic β cells causes type 1 diabetes mellitus (T1D), an autoimmune disease. Studies have demonstrated that there is heterogeneity in residual β-cell function in Caucasians; therefore, we aimed to evaluate β-cell function in Chinese autoimmune T1D patients.. β-cell function was determined using oral glucose tolerance testing or standardized steamed bread meal tolerance test in 446 participants with autoantibody-positive T1D. Clinical factors, such as age onset, sex, duration, body mass index, autoantibodies, other autoimmune diseases, diabetic ketoacidosis, hypoglycemia events, glycosylated hemoglobin, and insulin dose, were retrieved. We also analyzed single nucleotide polymorphism (SNP) data for C-peptides from 144 participants enrolled in the Chinese-T1D genome-wide association study.. Of 446 T1D patients, 98.5%, 97.4%, 86.9%, and 42.6% of individuals had detectable C-peptide values (≥ 0.003 nmol/L) at durations of < 1 year, 1 to 2 years, 3 to 6 years, and ≥ 7 years, respectively. A total of 60.7% of patients diagnosed at ≥ 18 years old and 15.8% of those diagnosed at < 18 years had detectable C-peptide after ≥ 7 years from the diagnosis. Furthermore, the patients diagnosed at ≥ 18 years old had higher absolute values of stimulated C-peptide (≥ 0.2 nmol/L). Diabetic ketoacidosis, hypoglycemia events, and insulin doses were shown to be associated with β-cell function. SNPs rs1770 and rs55904 were associated with C-peptide levels.. Our results have indicated that there are high residuals of β-cell mass in Chinese patients with autoimmune T1D. These findings may aid in the consideration of therapeutic strategies seeking prevention and reversal of β-cell function among Chinese T1D patients. Topics: Adolescent; Autoantibodies; Autoimmune Diseases; C-Peptide; China; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Progression; Genome-Wide Association Study; Humans; Hypoglycemia; Insulin | 2022 |
Transplantation of Pancreatic Islets Into the Omentum Using a Biocompatible Plasma-Thrombin Gel: First Experience at the Institute for Clinical and Experimental Medicine in Prague.
Islet transplantation represents an established therapeutic option for people with type 1 diabetes who have hypoglycemia unawareness syndrome and frequent problematic hypoglycemic episodes when other methods comprising diabetes education and use of technological support fail. Because the current standard method of islet infusion into the liver has some limitations, novel approaches are under investigation.. We report our first results with 2 cases of islet transplantation into an omental pouch using a biocompatible plasma-fibrin gel. The recipients received 12,350 and 5,350 islet equivalents per kilogram that were mixed with autologous plasma, seeded during a laparoscopic procedure on the omentum, overlaid with human thrombin solution, and fixed by flapping the omentum over.. During a 9-month follow-up, neither patient experienced any moderate or severe hypoglycemia. Their glucose control significantly improved, insulin dose decreased by approximately 50%, and C-peptide at 1 year was 0.22 and 0.14 pmol/mL, respectively. The postoperative course was uneventful, but C-peptide production in the first patient progressively declined at 1 year and hypoglycemic episodes recurred.. Though the results for these first 2 cases are not fully satisfactory, we have demonstrated the feasibility, safety, and ability of this novel method to restore insulin production. Further refinements to improve immediate islet survival seem necessary. Topics: Biomedical Research; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Omentum; Thrombin | 2022 |
Casual C peptide index: Predicting the subsequent need for insulin therapy in outpatients with type 2 diabetes under primary care.
Evaluation of residual beta cell function is indispensable in patients with type 2 diabetes as it informs not only diagnoses but also appropriate treatment modalities. However, there is a lack of convenient biomarkers for residual beta cell function. Therefore, we evaluated endogenous insulin level as a biomarker in outpatients who were being treated with insulin therapy and in patients who were introduced to insulin therapy after 4 years.. C-CPI and UCPCR were significantly lower in the insulin-treated patients than in the insulin-untreated patients (0.9 vs. 2.2, p < 0.0001; 24.7 vs. 75.5, p = 0.0003, respectively). Moreover, C-CPI were significantly lower in the insulin-requiring patients for 4 years than in the insulin-unrequiring patients (1.0 vs. 1.7, p = 0.0184). The multivariate logistic regression analysis revealed that both indicators of insulin secretion influenced the requirement for insulin therapy, but C-CPI could serve as the most convenient and useful biomarker for not only current insulin therapy requirements (p = 0.0002) but also the subsequent requirement for insulin therapy (p = 0.0008).. C-CPI could be determined easily, and it was found to be a more practical marker for outpatients; therefore, our findings would have critical implications for primary care. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Outpatients; Primary Health Care | 2022 |
Familial autoimmunity in pediatric patients with type 1 diabetes (T1D) and its associations with the severity of clinical presentation at diabetes diagnosis and with coexisting autoimmunity.
The aim was to evaluate the impact of familial autoimmunity on the age and severity of type 1 diabetes (T1D) presentation and on the coexistence of other autoimmune diseases.. We retrospectively evaluated the medical records of 121 children/adolescents (male: 63) followed in our Diabetic Clinic from 2002 to 2016.. Seventy-six patients (62.8%) had at least one relative with an autoimmune disease, Hashimoto's thyroiditis (49.5%) and T1D (22.3%) being the commonest. Children with familial autoimmunity were younger at T1D diagnosis (mean age ± SD) (6.766 ± 3.75). Median fasting c-peptide levels at presentation were not related to familial autoimmunity. Patients with familial autoimmunity more often exhibited GADA autoantibody positivity at diagnosis. The larger the number of the patient's relatives diagnosed with an autoimmune disease, the higher were the patient's GADA levels (Spearman's rho test = 0.19, p = 0.049). Children with a first-degree relative with autoimmunity had a coexisting autoimmune disorder at a significantly higher percentage (p = 0.016). Family history of autoimmunity was negatively associated with the presence of diabetic ketoacidosis (DKA) (p = 0.024). Patients with a relative with T1D less frequently exhibited DKA at diagnosis (12.8 vs. 87.2%, p = 0.003). The presence of DKA was associated with younger age (p = 0.05) and lower c-peptide levels (p = 0.033).. Familial autoimmunity was present in 62.8% of children with T1D, autoimmune thyroiditis and T1D being the two most frequent familial autoimmune diseases. Familial autoimmunity reduced the risk of DKA at diagnosis, but these patients were younger and had higher levels of pancreatic autoantibodies and a greater risk of developing additional autoimmune diseases. Topics: Autoantibodies; Autoimmune Diseases; Autoimmunity; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Hashimoto Disease; Humans; Male; Retrospective Studies | 2022 |
Which C-peptide assay do you use? Increasing need for describing C-peptide assay performance.
Many C-peptide assays are commercially available for research and routine use. However, not all assays yield consistent results, especially in the low concentration ranges. We searched the literature describing C-peptide measurements to assess which assays are mainly used in the diabetes research field and if they are specified. Percentages of publications on C-peptide measurements in type 1 diabetes (T1D), type 2 diabetes (T2D) and other forms of diabetes were 32%, 54% and 14%, respectively. In only 54% of the publications the used assay was specified. Information on detection limit, measurement range and variation was provided in 12%, 2% and 11% of publications, respectively. In 22% of all publications no C-peptides concentrations were mentioned. This may be a problem especially for T1D research, where measuring very low levels of C-peptide is becoming increasingly important and concordance between assays is low. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans | 2022 |
Clinical Characteristics Associated with the Development of Diabetic Ketoacidosis in Patients with Type 2 Diabetes.
Objective This study analyzed the clinical and laboratory parameters that might influence the clinical outcomes of patients with type 2 diabetes who develop diabetic ketoacidosis (DKA), which has not been well investigated. Methods We reviewed the clinical and laboratory data of 158 patients who were hospitalized due to DKA between January 2006 and June 2019 and compared the data of patients stratified by the type of diabetes. In addition, the patients with type 2 diabetes were subdivided according to age, and their clinical and laboratory findings were evaluated. Results Patients with type 2 diabetes had a longer symptom duration associated with DKA, higher body mass index (BMI), and higher C-peptide levels than those with type 1 diabetes (p<0.05). Among patients with type 2 diabetes, elderly patients (≥65 years old) had a longer duration of diabetes, higher frequency of DKA onset under diabetes treatment, higher effective osmolarity, lower BMI, and lower urinary C-peptide levels than nonelderly patients (<65 years old) (p<0.05). A correlation analysis showed that age was significantly negatively correlated with the index of insulin secretory capacity. Conclusion Patients with DKA and type 2 diabetes had a higher BMI and insulin secretion capacity than those with type 1 diabetes. However, elderly patients with type 2 diabetes, unlike younger patients, were characterized by a lean body, impaired insulin secretion, and more frequent DKA development while undergoing treatment for diabetes. Topics: Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Humans; Insulin Secretion; Retrospective Studies | 2022 |
The Theory of Hyperlipidemic Memory of Type 1 Diabetes.
A literature search was conducted to identify publications addressing the early phases of lipid phenotypes in children and adults with either type 1 diabetes or type 2 diabetes. Medline, EMBASE, and Ovid were searched using the following search terms: Topics: Adolescent; Atherosclerosis; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Lipids; Remission Induction | 2022 |
Pancreatic shear wave elastography in children with type 1 diabetes: relation to diabetes duration, glycemic indices, fasting C-peptide and diabetic complications.
Little is known about changes in the pancreas as the course of type 1 diabetes progresses. Recently, shear wave elastography (SWE) emerged as a tool for assessing pancreatic stiffness in chronic pancreatitis and pancreatic cancer with a few studies assessing it in diabetes.. To compare pancreatic SWE in children with recent-onset and long-standing type 1 diabetes to healthy controls and to correlate it with diabetes duration, glycated hemoglobin (HbA1C), functional B cell reserve (fasting C-peptide) and diabetic complications.. Fifty children with type 1 diabetes (25 with recent-onset and 25 with long-standing type 1 diabetes) and 50 controls were enrolled. Diabetes duration, insulin therapy, fundoscopic examination of the eyes and the neuropathy disability score were assessed. Fasting C-peptide, lipids, HbA1C and urinary albumin-creatinine ratio were measured. Pancreatic SWE was measured using the General Electric Logiq P9 ultrasound system.. The mean SWE of the studied children with recent-onset type 1 diabetes was 4.81±0.62 kilopascals (Kpa), those with long-standing type 1 diabetes was 7.10±1.56Kpa and for controls was 5.57±0.27 Kpa (P<0.001). SWE was positively correlated to diabetes duration (P<0.001) and negatively correlated to fasting C-peptide (P<0.001). Regarding diabetes complications, SWE was positively correlated to frequency of severe hypoglycemia (P=0.005), HbA1C (P=0.03), low-density lipoproteins (P<0.001) and cholesterol (P<0.001) and significantly related to diabetic neuropathy (P=0.04) and nephropathy (P=0.05). Diabetes duration, fasting C-peptide, HbA1C and frequency of severe hypoglycemia were the significant independent variables related to SWE increase by multivariable regression analysis.. Pancreatic SWE changes significantly with duration of type 1 diabetes, being lowest in those with recent-onset type 1 diabetes and highest in those with long-standing type 1 diabetes, particularly those with diabetic nephropathy and neuropathy. Topics: C-Peptide; Child; Diabetes Complications; Diabetes Mellitus, Type 1; Elasticity Imaging Techniques; Fasting; Glycated Hemoglobin; Glycemic Index; Humans; Hypoglycemia; Pancreas | 2022 |
Association between single nucleotide polymorphisms in non-coding regions of the insulin (INS) gene and schizophrenia.
Schizophrenia is a psychotic disorder with high heritability. There are also indications that impaired cellular signalling via the insulin receptor-A and the insulin-like growth factor 1 receptor may play a role in its pathogenesis. Insulin, and possibly also C-peptide, are ligands to these receptors. The insulin gene, coding both insulin and C-peptide, has however not been genetically studied in schizophrenia. Therefore, this study was undertaken to investigate the involvement of this gene in schizophrenia susceptibility.. For identification of single nucleotide polymorphisms (SNPs) of interest, the whole insulin gene and parts of its promoter region were first DNA sequenced in two subgroups of the study population (37 schizophrenia patients with heredity for schizophrenia or related psychosis, and 25 controls), and mapped to the reference sequence. Then, 7 identified SNPs of potential interest were typed by TaqMan® SNP Genotyping Assays in the whole study population, consisting of 94 patients with schizophrenia and 60 controls.. Allele frequencies tended to differ between patients and controls for two of the 7 SNPs, rs5505 and rs3842749 (p=0.077 and p=0.078, respectively), whereas subgroup analyses of diabetes mellitus (type 1 or 2) and/ or heredity for diabetes mellitus (type 1 or 2) in patients and controls showed overall significant differences in genotype/ allele frequencies solely for rs5505 (p=0.021/ 0.023).. These findings are of interest, as the two SNPs - rs5505 and rs3842749 - may have regulatory function on the coding of insulin and C-peptide, against which increased antibody reactivity has been previously reported in schizophrenia. Topics: C-Peptide; Diabetes Mellitus, Type 1; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Insulin; Polymorphism, Single Nucleotide; Schizophrenia | 2022 |
Circulating C-Peptide Levels in Living Children and Young People and Pancreatic β-Cell Loss in Pancreas Donors Across Type 1 Diabetes Disease Duration.
C-peptide declines in type 1 diabetes, although many long-duration patients retain low, but detectable levels. Histological analyses confirm that β-cells can remain following type 1 diabetes onset. We explored the trends observed in C-peptide decline in the UK Genetic Resource Investigating Diabetes (UK GRID) cohort (N = 4,079), with β-cell loss in pancreas donors from the network for Pancreatic Organ donors with Diabetes (nPOD) biobank and the Exeter Archival Diabetes Biobank (EADB) (combined N = 235), stratified by recently reported age at diagnosis endotypes (<7, 7-12, ≥13 years) across increasing diabetes durations. The proportion of individuals with detectable C-peptide declined beyond the first year after diagnosis, but this was most marked in the youngest age group (<1-year duration: age <7 years: 18 of 20 [90%], 7-12 years: 107 of 110 [97%], ≥13 years: 58 of 61 [95%] vs. 1-5 years postdiagnosis: <7 years: 172 of 522 [33%], 7-12 years: 604 of 995 [61%], ≥13 years: 225 of 289 [78%]). A similar profile was observed in β-cell loss, with those diagnosed at younger ages experiencing more rapid loss of islets containing insulin-positive (insulin+) β-cells <1 year postdiagnosis: age <7 years: 23 of 26 (88%), 7-12 years: 32 of 33 (97%), ≥13 years: 22 of 25 (88%) vs. 1-5 years postdiagnosis: <7 years: 1 of 12 (8.3%), 7-12 years: 7 of 13 (54%), ≥13 years: 7 of 8 (88%). These data should be considered in the planning and interpretation of intervention trials designed to promote β-cell retention and function. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Infant; Insulin-Secreting Cells; Pancreas; Tissue Donors | 2022 |
Insulin Requirement and Complications Associated With Serum C-Peptide Decline in Patients With Type 1 Diabetes Mellitus During 15 Years After Diagnosis.
C-peptide is conventionally used in assessing pancreatic function in patients with diabetes mellitus. The clinical significance of this molecule during the course of type 1 diabetes mellitus (T1DM) has been recently revisited. This study aimed to investigate the natural course of C-peptide in T1DM patients over the period of 15 years and analyze the association between the residual C-peptide and diabetes complications.. This retrospective study included a total of 234 children and adolescents with T1DM. Patient data including sex, age at diagnosis, anthropometric measures, daily insulin dose, serum HbA1c, post-prandial serum C-peptide levels, lipid profiles, and diabetic complications at the time of diagnosis and 1, 3, 5, 10, and 15 years after diagnosis were retrospectively collected.. Among the 234 patients, 101 were men and 133 were women, and the mean patient age at initial diagnosis was 8.3 years. Serum C-peptide decreased constantly since the initial diagnosis, and showed a significant decline at 3 years after diagnosis. At 15 years after diagnosis, only 26.2% of patients had detectable serum C-peptide levels. The subgroup with older patients and patients with higher BMI standard deviation score showed higher mean serum C-peptide, but the group-by-time results were not significant, respectively. Patients with higher serum C-peptide required lower doses of insulin and had fewer events of diabetic ketoacidosis.. Serum C-peptide decreased consistently since diagnosis of T1DM, showing a significant decline after 3 years. Patients with residual C-peptide required a lower dose of insulin and had a lower risk for diabetic ketoacidosis. Topics: Adolescent; C-Peptide; Child; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Progression; Female; Humans; Insulin; Male; Retrospective Studies | 2022 |
Oral Glucose Tolerance Test Measures of First-phase Insulin Response and Their Predictive Ability for Type 1 Diabetes.
Decreased first-phase insulin response (FPIR) during intravenous glucose tolerance testing (IVGTT) is an early indicator of β-cell dysfunction and predictor of type 1 diabetes (T1D).. Assess whether oral glucose tolerance test (OGTT) measures could serve as FPIR alternatives in their ability to predict T1D in autoantibody positive (Aab+) subjects.. OGTT and IVGTT were performed within 30 days of each other. Eleven OGTT variables were evaluated for (1) correlation with FPIR and (2) T1D prediction.. Type 1 Diabetes TrialNet "Oral Insulin for Prevention of Diabetes in Relatives at Risk for T1D" (TN-07) and Diabetes Prevention Trial-Type 1 Diabetes (DPT-1) studies clinical sites.. TN-07 (n = 292; age 9.4 ± 6.1 years) and DPT-1 (n = 194; age 15.1 ± 10.0 years) Aab + relatives of T1D individuals.. (1) Correlation coefficients of OGTT measures with FPIR and (2) T1D prediction at 2 years using area under receiver operating characteristic (ROCAUC) curves.. Index60 showed the strongest correlation in DPT-1 (r = -0.562) but was weaker in TN-07 (r = -0.378). C-peptide index consistently showed good correlation with FPIR across studies (TN-07, r = 0.583; DPT-1, r = 0.544; P < 0.0001). Index60 and C-peptide index had the highest ROCAUCs for T1D prediction (0.778 vs 0.717 in TN-07 and 0.763 vs 0.721 in DPT-1, respectively; P = NS), followed by FPIR (0.707 in TN-07; 0.628 in DPT-1).. C-peptide index was the strongest measure to correlate with FPIR in both studies. Index60 and C-peptide index had the highest predictive accuracy for T1D and were comparable. OGTTs could be considered instead of IVGTTs for subject stratification in T1D prevention trials. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Young Adult | 2022 |
Continuous glucose monitoring to assess glucose variability in type 3c diabetes.
The effectiveness of continuous glucose monitoring (CGM) in maintaining glycaemic control in type 1 diabetes mellitus and type 2 diabetes mellitus has been well demonstrated. However, the degree of glycaemic variability (GV) in people with type 3c diabetes mellitus has not been fully explored using CGM. This study aims to evaluate GV in type 3c diabetes mellitus participants and compare it to type 1 diabetes mellitus and type 2 diabetes mellitus.. Participants were grouped according to type of diabetes. GV, defined as percentage coefficient of variation (%CV), and other glycaemic indices were obtained using CGM (FreeStyle Libre, Abbott, Australia) from 82 participants across all three cohorts over a 14-day period. Comparison of baseline characteristics and GV were performed across all groups. Correlation of GV with C-peptide values, and whether pancreatic supplementation had an effect on GV were also assessed in the type 3c diabetes mellitus cohort.. GV of type 3c diabetes mellitus participants was within the recommended target of less than %CV 36% (p = 0.004). Type 3c diabetes mellitus participants had the lowest GV among the three groups (p = 0.001). There was a trend for lower C-peptide levels to be associated with higher GV in type 3c diabetes mellitus participants (p = 0.22). Pancreatic enzyme supplementation in type 3c diabetes mellitus participants did not have an effect on GV (p = 0.664).. Although type 3c diabetes mellitus participants were the least variable, they had the highest mean glucose levels and estimated HbA Topics: Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose; Glycated Hemoglobin; Humans; Hyperglycemia | 2022 |
Outcomes Following Extrahepatic and Intraportal Pancreatic Islet Transplantation: A Comparative Cohort Study.
Preliminary studies show promise for extrahepatic islet transplantation (ITx). However, clinical comparisons with intraportal ITx outcomes remain limited.. This single-center cohort study evaluates patients receiving extrahepatic or intraportal ITx between 1999 and 2018. Primary outcome was stimulated C-peptide level. Secondary outcomes were fasting plasma glucose, BETA-2 scores, and fasting C-peptide level. Multivariable logistic modeling evaluated factors independently associated with a composite variable of early graft failure and primary nonfunction within 60 d of ITx.. Of 264 patients, 9 (3.5%) received extrahepatic ITx (gastric submucosal = 2, subcutaneous = 3, omental = 4). Group demographics were similar at baseline (age, body mass index, diabetes duration, and glycemic control). At 1-3 mo post-first infusion, patients receiving extrahepatic ITx had significantly lower stimulated C-peptide (0.05 nmol/L versus 1.2 nmol/L, P < 0.001), higher fasting plasma glucose (9.3 mmol/L versus 7.3 mmol/L, P < 0.001), and lower BETA-2 scores (0 versus 11.6, P < 0.001) and SUITO indices (1.5 versus 39.6, P < 0.001) compared with those receiving intraportal ITx. Subjects receiving extrahepatic grafts failed to produce median C-peptide ≥0.2 nmol/L within the first 60 d after transplant. Subsequent intraportal infusion following extrahepatic transplants achieved equivalent outcomes compared with patients receiving intraportal transplant alone. Extrahepatic ITx was independently associated with early graft failure/primary non-function (odds ratio 1.709, confidence interval 73.8-39 616.0, P < 0.001), whereas no other factors were independently predictive.. Using current techniques, intraportal islet infusion remains the gold standard for clinical ITx, with superior engraftment, graft function, and glycemic outcomes compared with extrahepatic transplantation of human islets. Topics: Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans Transplantation | 2022 |
Enhanced T Cell Glucose Uptake Is Associated With Progression of Beta-Cell Function in Type 1 Diabetes.
Abnormal intracellular glucose/fatty acid metabolism of T cells has tremendous effects on their immuno-modulatory function, which is related to the pathogenesis of autoimmune diseases. However, the association between the status of intracellular metabolism of T cells and type 1 diabetes is unclear. This study aimed to investigate the uptake of glucose and fatty acids in T cells and its relationship with disease progression in type 1 diabetes.. A total of 86 individuals with type 1 diabetes were recruited to detect the uptake of glucose and fatty acids in T cells. 2-NBDG uptake and expression of glucose transporter 1 (GLUT1); or BODIPY uptake and expression of carnitine palmitoyltransferase 1A(CPT1A) were used to assess the status of glucose or fatty acid uptake in T cells. Patients with type 1 diabetes were followed up every 3-6 months for 36 months, the progression of beta-cell function was assessed using generalized estimating equations, and survival analysis was performed to determine the status of beta-cell function preservation (defined as 2-hour postprandial C-peptide >200 pmol/L).. Patients with type 1 diabetes demonstrated enhanced intracellular glucose uptake of T cells as indicated by higher 2NBDG uptake and GLUT1 expression, while no significant differences in fatty acid uptake were observed. The increased T cells glucose uptake is associated with lower C-peptide and higher hemoglobin A1c levels. Notably, patients with low T cell glucose uptake at onset maintained high levels of C-peptide within 36 months of the disease course [fasting C-petite and 2-hour postprandial C-peptide are 60.6 (95%CI: 21.1-99.8) pmol/L and 146.3 (95%CI: 14.1-278.5) pmol/L higher respectively], And they also have a higher proportion of beta-cell function preservation during this follow-up period (. Intracellular glucose uptake of T cells is abnormally enhanced in type 1 diabetes and is associated with beta-cell function and its progression. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids; Glucose; Glucose Transporter Type 1; Humans; Insulin; T-Lymphocytes | 2022 |
The association of physical activity to oral glucose tolerance test outcomes in multiple autoantibody positive children: The TEDDY Study.
To examine the association of physical activity (PA), measured by accelerometry, to hemoglobin AIC (HbA1c) and oral glucose tolerance test (OGTT) outcomes in children who were multiple persistent confirmed autoantibody positive for type 1 diabetes (T1D).. The Environmental Determinants of Diabetes in the Young (TEDDY) multinational study followed children from birth. Children ≥3 years of age who were multiple persistent confirmed autoantibody positive were monitored by OGTTs every 6 months. TEDDY children's PA was measured by accelerometry beginning at 5 years of age. We examined the relationship between moderate plus vigorous (mod + vig) PA, HbA1c, and OGTT in 209 multiple autoantibody children who had both OGTT and PA measurements.. Mod + vig PA was associated with both glucose and C-peptide measures (fasting, 120-min, and AUC); higher mod + vig PA was associated with a better OGTT response primarily in children with longer duration of multiple autoantibody positivity. Mod + vig PA also interacted with child age; lower mod + vig PA was associated with a greater increase in C-peptide response across age. Mod + vig PA was not related to fasting insulin, HOMA-IR or HbA1c.. The OGTT is the gold standard for diabetes diagnosis and is used to monitor those at high risk for T1D. We found higher levels of mod + vig PA were associated with better OGTT outcomes in children ≥5 years of age who have been multiple autoantibody positive for longer periods of time. Physical activity should be the focus of future efforts to better understand the determinants of disease progression in high-risk children. Topics: Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Exercise; Glucose; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Infant | 2022 |
Characteristics of children and adolescents with newly diagnosed Fibrocalculous pancreatitis diabetes (FCPD) and type 1 diabetes: A study from Eastern India.
We aimed to identify clinical characteristics and biochemical parameters at presentation in newly diagnosed children and adolescents with Fibrocalculous pancreatic diabetes (FCPD) and compare them with Type 1 Diabetes (T1D) children.. A retrospective chart review yielded 226 patients (below 18 years) who presented and fulfilled diagnostic criteria of diabetes mellitus. Classification of diabetes was based on American Diabetes Association (ADA), World Health Organization (WHO), International Society for Paediatric and Adolescent Diabetes (ISPAD), and Mohan's criteria and all patients underwent abdominal X-ray.. A total of 31 (13.7%) patients fulfilled criteria of FCPD and 63 (27.9%) of autoantibody positive T1D. When comparing FCPD with T1D at presentation, FCPD patients were older, 14.23 years vs 11.32 years. Fewer FCPD patients presented with Diabetic Ketoacidosis (3.2% vs 34.9%), osmotic symptoms (54.8% vs 93.7%) with significantly longer median duration of symptoms (4.0 vs 1.0 months) and had more abdominal pain (58.06% vs 6.3%) & diarrhoea (38.71% vs 1.6%) as compared to patients with T1D". FCPD patients had higher c-peptide levels (median-0.85 vs 0.61) and required higher mean dose of insulin compared to T1D (1.16 U/kg vs 1.01 U/kg). At presentation fasting plasma glucose was significantly higher in T1D than FCPD, but no difference was noted in post prandial glucose and HbA1c.. There is a significant difference in clinical characteristics and biochemical parameters at presentation between FCPD and T1D patients with a longer symptom duration but insidious course in the former. To the best of our knowledge, this is the first study to report suitable cut-offs for age, c-peptide, duration of symptoms and insulin dose requirement which could be helpful for differentiating FCPD from T1DM patients. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; India; Insulin; Pancreatitis; Retrospective Studies | 2022 |
A classification and regression tree analysis identifies subgroups of childhood type 1 diabetes.
Diabetes in childhood and adolescence includes autoimmune and non-autoimmune forms with heterogeneity in clinical and biochemical presentations. An unresolved question is whether there are subtypes, endotypes, or theratypes within these forms of diabetes.. The multivariable classification and regression tree (CART) analysis method was used to identify subgroups of diabetes with differing residual C-peptide levels in patients with newly diagnosed diabetes before 20 years of age (n=1192). The robustness of the model was assessed in a confirmation and prognosis cohort (n=2722).. The analysis selected age, haemoglobin A1c (HbA1c), and body mass index (BMI) as split parameters that classified patients into seven islet autoantibody-positive and three autoantibody-negative groups. There were substantial differences in genetics, inflammatory markers, diabetes family history, lipids, 25-OH-Vitamin D3, insulin treatment, insulin sensitivity and insulin autoimmunity among the groups, and the method stratified patients with potentially different pathogeneses and prognoses. Interferon-ɣ and/or tumour necrosis factor inflammatory signatures were enriched in the youngest islet autoantibody-positive groups and in patients with the lowest C-peptide values, while higher BMI and type 2 diabetes characteristics were found in older patients. The prognostic relevance was demonstrated by persistent differences in HbA1c at 7 years median follow-up.. This multivariable analysis revealed subgroups of young patients with diabetes that have potential pathogenetic and therapeutic relevance.. The work was supported by funds from the German Federal Ministry of Education and Research (01KX1818; FKZ 01GI0805; DZD e.V.), the Innovative Medicine Initiative 2 Joint Undertaking INNODIA (grant agreement No. 115797), the German Robert Koch Institute, and the German Diabetes Association. Topics: Adolescent; Autoantibodies; Autoimmunity; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; Young Adult | 2022 |
Recurrent hypoglycemic coma and diabetic ketoacidosis caused by insulin antibody. A rare case of type 1 diabetes mellitus.
Insulin antibodies (IAs) induced by exogenous insulin rarely cause hypoglycemia. However, insulin autoantibodies (IAAs) in insulin autoimmune syndrome (IAS) can cause hypoglycemia. The typical manifestations of IAS are fasting or postprandial hypoglycemia, elevated insulin level, decreased C-peptide levels, and positive IAA. We report a 45-year-old male with type 1 diabetes mellitus (T1DM) treated with insulin analogues suffering from recurrent hypoglycemic coma and diabetic ketoacidosis (DKA). His symptoms were caused by exogenous insulin and were similar to IAS. A possible reason was that exogenous insulin induced IA. IA titers were 61.95% (normal: < 5%), and the concentrations of insulin and C-peptide were > 300 mU/L and < 0.02 nmol/L when hypoglycemia occurred. Based on his clinical symptoms and other examinations, he was diagnosed with hyperinsulinemic hypoglycemia caused by IA. His symptoms improved after changing insulin regimens from insulin lispro plus insulin detemir to recombinant human insulin (Gensulin R) and starting prednisone. Topics: Autoimmune Diseases; C-Peptide; Coma; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Antibodies; Male; Middle Aged | 2022 |
Estimation of Early Graft Function Using the BETA-2 Score Following Clinical Islet Transplantation.
Little is known about how early islet graft function evolves in the clinical setting. The BETA-2 score is a validated index of islet function that can be calculated from a single blood sample and lends itself to frequent monitoring of graft function. In this study, we characterized early graft function by calculating weekly BETA-2 score in recipients who achieved insulin independence after single transplant (group 1, Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Graft Survival; Humans; Insulin; Islets of Langerhans Transplantation | 2022 |
Index60 Is Superior to HbA1c for Identifying Individuals at High Risk for Type 1 Diabetes.
HbA1c from ≥ 5.7% to < 6.5% (39-46 mmol/mol) indicates prediabetes according to American Diabetes Association guidelines, yet its identification of prediabetes specific for type 1 diabetes has not been assessed. A composite glucose and C-peptide measure, Index60, identifies individuals at high risk for type 1 diabetes.. We compared Index60 and HbA1c thresholds as markers for type 1 diabetes risk.. TrialNet Pathway to Prevention study participants with ≥ 2 autoantibodies (GADA, IAA, IA-2A, or ZnT8A) who had oral glucose tolerance tests and HbA1c measurements underwent 1) predictive time-dependent modeling of type 1 diabetes risk (n = 2776); and 2) baseline comparisons between high-risk mutually exclusive groups: Index60 ≥ 2.04 (n = 268) vs HbA1c ≥ 5.7% (n = 268). The Index60 ≥ 2.04 threshold was commensurate in ordinal ranking with the standard prediabetes threshold of HbA1c ≥ 5.7%.. In mutually exclusive groups, individuals exceeding Index60 ≥ 2.04 had a higher cumulative incidence of type 1 diabetes than those exceeding HbA1c ≥ 5.7% (P < 0.0001). Appreciably more individuals with Index60 ≥ 2.04 were at stage 2, and among those at stage 2, the cumulative incidence was higher for those with Index60 ≥ 2.04 (P = 0.02). Those with Index60 ≥ 2.04 were younger, with lower BMI, greater autoantibody number, and lower C-peptide than those with HbA1c ≥ 5.7% (P < 0.0001 for all comparisons).. Individuals with Index60 ≥ 2.04 are at greater risk for type 1 diabetes with features more characteristic of the disorder than those with HbA1c ≥ 5.7%. Index60 ≥ 2.04 is superior to the standard HbA1c ≥ 5.7% threshold for identifying prediabetes in autoantibody-positive individuals. These findings appear to justify using Index60 ≥ 2.04 as a prediabetes criterion in this population. Topics: Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Prediabetic State | 2022 |
Using Glycated Albumin and Stimulated C-Peptide to Define Partial Remission in Type 1 Diabetes.
To propose a new definition of partial remission (PR) for patients with type 1 diabetes (T1D) of all-ages using insulin dose and glycated albumin (GA), and find the optimal cut-off values for stimulated C-peptide to diagnose PR in different age-groups.. Patients with newly diagnosed T1D (n=301) were included. GA/insulin dose was used to diagnose PR, and insulin dose-adjusted glycated albumin (IDAGA) was proposed to facilitate clinical application. The optimal diagnostic levels of IDAGA and stimulated C-peptide were determined in different age-groups (≤ 12y, 12-18y and ≥ 18y). Furthermore, the diagnostic consistency between different PR definitions was studied.. GA≤ 23%/insulin dose ≤ 0.5u/kg/day was used to define PR, and IDAGA (GA (%) + 40 * insulin dose(u/kg/day)) ≤ 40 was feasible in all age-groups. Whereas, the optimal diagnostic level showed difference for stimulated C-peptide (265.5, 449.3 and 241.1 pmol/L for the ≤ 12y, 12-18y and ≥ 18y age-group, respectively). About 40% of patients met the PR definition by stimulated C-peptide but not GA/insulin dose or IDAGA, who showed dyslipidemia and higher insulin resistance.. A new definition of the PR phase is proposed using GA/insulin dose, and the calculated IDAGA≤ 40 applies to all age-groups. The stimulated C-peptide to diagnose PR is the highest in the 12-18y age-group, which reflects the effect of puberty on metabolism. For patients with insulin resistance, it is not recommended to use stimulated C-peptide alone to diagnose PR. Topics: C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Glycated Serum Albumin; Glycation End Products, Advanced; Humans; Insulin; Insulin Resistance; Serum Albumin | 2022 |
The Transition From a Compensatory Increase to a Decrease in C-peptide During the Progression to Type 1 Diabetes and Its Relation to Risk.
To define the relationship between glucose and C-peptide during the progression to type 1 diabetes (T1D).. We longitudinally studied glucose and C-peptide response curves (GCRCs), area under curve (AUC) for glucose, and AUC C-peptide from oral glucose tolerance tests (OGTTs), and Index60 (which integrates OGTT glucose and C-peptide values) in Diabetes Prevention Trial-Type 1 (DPT-1) (n = 72) and TrialNet Pathway to Prevention Study (TNPTP) (n = 82) participants who had OGTTs at baseline and follow-up time points before diagnosis.. Similar evolutions of GCRC configurations were evident between DPT-1 and TNPTP from baseline to 0.5 years prediagnosis. Whereas AUC glucose increased throughout from baseline to 0.5 years prediagnosis, AUC C-peptide increased from baseline until 1.5 years prediagnosis (DPT-1, P = 0.004; TNPTP, P = 0.012) and then decreased from 1.5 to 0.5 years prediagnosis (DPT-1, P = 0.017; TNPTP, P = 0.093). This change was mostly attributable to change in the late AUC C-peptide response (i.e., 60- to 120-min AUC C-peptide). Median Index60 values of DPT-1 (1.44) and TNPTP (1.05) progressors to T1D 1.5 years prediagnosis (time of transition from increasing to decreasing AUC C-peptide) were used as thresholds to identify individuals at high risk for T1D in the full cohort at baseline (5-year risk of 0.75-0.88 for those above thresholds).. A transition from an increase to a decrease in AUC C-peptide ∼1.5 years prediagnosis was validated in two independent cohorts. The median Index60 value at that time point can be used as a pathophysiologic-based threshold for identifying individuals at high risk for T1D. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Glucose Tolerance Test; Humans | 2022 |
[Residual insulin secretion and management of type 1 diabetes: Interest of new C-peptide assays].
Plasma C-peptide represents a direct measure of endogenous insulin secretion. The development of new assays for measuring C-peptide have made it possible to demonstrate that a low insulin secretion persists in 30 to 80% of subjects with type 1 diabetes (T1D), even among those with long-standing disease. Several studies have established that the persistence of B cell function of the islets of Langerhans is associated with a protection against the development of microvascular complications and resulted in a significant reduction in the prevalence of severe hypoglycaemia in people with T1D. Further studies are needed to clarify the underlying pathophysiological mechanisms and the therapeutic strategies that would maintain B-cell function and thus improve the quality of life of patients with T1D.. Le peptide-C plasmatique constitue une mesure directe de la sécrétion endogène d’insuline. Le développement de nouveaux dosages du peptide-C a permis de démontrer qu’il persiste chez 30 à 80 % des sujets diabétiques de type 1 (DT1) une faible sécrétion d’insuline, même sur le long terme. Plusieurs études ont établi que la persistance de la fonction B des îlots de Langerhans était associée à une protection contre le développement des complications microvasculaires et engendrait une réduction significative de la prévalence des hypoglycémies sévères chez les personnes DT1. Mais des études complémentaires sont encore nécessaires afin de préciser les mécanismes physiopathologiques sous-jacents et les stratégies thérapeutiques qui permettraient de maintenir la fonction de la cellule B et d’améliorer ainsi la qualité de vie des sujets avec un DT1. Topics: C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Humans; Insulin; Insulin Secretion; Quality of Life | 2022 |
Clinical features, biochemistry, and HLA-DRB1 status in youth-onset type 1 diabetes in Mali.
Limited information is available regarding youth-onset diabetes in Mali. We investigated demographic, clinical, biochemical, and genetic features in new diabetes cases in children and adolescents.. The study was conducted at Hôpital du Mali in Bamako. A total of 132 recently-diagnosed cases <21 years were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, glutamic acid decarboxylase-65 (GAD-65) and islet antigen-2 (IA2) autoantibodies) were assessed. DNA was genotyped for HLA-DRB1 using high-resolution genotyping technology.. A total of 130 cases were clinically diagnosed as type 1 diabetes (T1D), one with type 2 diabetes (T2D), and one with secondary diabetes. A total of 66 (50.8%) T1D cases were males and 64 (49.2%) females, with a mean age at diagnosis of 13.8 ± 4.4 years (range 0.8-20.7 years) peak onset of 15 years. 58 (44.6%) presented in diabetic ketoacidosis; with 28 (21.5%) IA2 positive, 76 (58.5%) GAD-65 positive, and 15 (11.5%) positive for both autoantibodies. HLA was also genotyped in 195 controls without diabetes. HLA-DRB1 genotyping of controls and 98 T1D cases revealed that DRB1*03:01, DRB1*04:05, and DRB1*09:01 alleles were predisposing for T1D (odds ratios [ORs]: 2.82, 14.76, and 3.48, p-values: 9.68E-5, 2.26E-10, and 8.36E-4, respectively), while DRB1*15:03 was protective (OR = 0.27; p-value = 1.73E-3). No significant differences were observed between T1D cases with and without GAD-65 and IA2 autoantibodies. Interestingly, mean C-peptide was 3.6 ± 2.7 ng/ml (1.2 ± 0.9 nmol/L) in T1D cases at diagnosis.. C-peptide values were higher than expected in those diagnosed as T1D and autoantibody rates lower than in European populations. It is quite possible that some cases have an atypical form of T1D, ketosis-prone T2D, or youth-onset T2D. This study will help guide assessment and individual management of Malian diabetes cases, potentially enabling healthier outcomes. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Glutamate Decarboxylase; HLA-DRB1 Chains; Humans; Infant; Male; Mali; Young Adult | 2022 |
CLOuDs Disperse - Top-Notch Glucose Control and Residual C-Peptide Secretion.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Humans; Hypoglycemic Agents; Insulin | 2022 |
Immunological balance between Treg and Th17 lymphocytes as a key element of type 1 diabetes progression in children.
Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; T-Lymphocytes, Regulatory; Th17 Cells | 2022 |
New-onset type 1 diabetes mellitus as a delayed immune-related event after discontinuation of nivolumab: A case report.
Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. However, they may cause immune-related adverse events. Although there have been a few reports of new-onset type 1 diabetes mellitus (T1DM) during ICI treatment, T1DM as a delayed immune-related event after discontinuing immunotherapy is extremely rare. Herein, we report the case of an elderly veteran who presented with diabetic ketoacidosis 4 months after the discontinuation of treatment with nivolumab.. A 74-year-old veteran was treated with second-line nivolumab for advanced non-small cell lung cancer. After 9 treatment cycles, the administration was discontinued due to fatigue. Four months later, he was admitted to the emergency department in a stuporous mental state and hyperglycemia, with high glycosylated hemoglobin levels (10.6%). C-peptide levels were significantly decreased, with negative islet autoantibodies.. We diagnosed nivolumab-induced T1DM. There were no laboratory results indicating a new thyroid dysfunction or adrenal insufficiency, which are typical endocrine adverse reactions.. Since the hypothalamic and pituitary functions were preserved and only the pancreatic endocrine capacity was impaired, we administered continuous intravenous insulin injections, with fluid and electrolyte replacement.. His serum glucose levels decreased, and symptoms improved; hence, on the 8 day of hospitalization, we switched to multiple daily insulin injections.. The present case indicates that regular glucose monitoring and patient education are needed for diabetic ketoacidosis after the discontinuation of ICI therapy. Topics: Aged; Autoantibodies; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Carcinoma, Non-Small-Cell Lung; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Electrolytes; Glycated Hemoglobin; Humans; Immune Checkpoint Inhibitors; Lung Neoplasms; Male; Nivolumab | 2022 |
Skeletal status in children and adolescents with new-onset type 1 diabetes: a preliminary study based on bone densitometry and quantitative ultrasound.
Type 1 diabetes (T1D) represents a risk factor for bone loss and impaired bone quality.. We conducted an exploratory retrospective cross-sectional study involving youths with new-onset T1D, to investigate the relationship between lumbar spine dual-energy X-ray absorptiometry (DXA) and phalangeal quantitative ultrasound (QUS) measurements, along with their correlation with markers of bone turnover, glucose homeostasis, and residual β-cell function.. 17 children and adolescents (8 females) with recent-onset T1D were enrolled into this study. Lumbar spine areal bone mineral density (aBMD) and age-adjusted amplitude-dependent speed of sound (AD-SoS) Z-scores were indicative of low BMD status (≤ -2.0 SD) in 11.7% and 17.6% of participants, respectively. Spearman's correlation analysis revealed significant inverse correlations between AD-SoS values and circulating levels of β-CrossLaps, alkaline phosphatase, and osteocalcin, along with a significant positive correlation between bone transmission time (BTT) values and fasting plasma C-peptide (FCP) levels. There was no statistically significant correlation between DXA-QUS parameters, fasting plasma glucose (FPG), and glycated haemoglobin (HbA1c). Finally, there was a significant positive correlation between lumbar spine aBMD and BTT values.. Our study suggests that DXA and/or QUS parameters may be altered in a small proportion of T1D children and adolescents at the disease onset. Additionally, residual β-cell function may represent a protective factor against T1D-related detrimental skeletal changes. Large and long-term prospective studies are needed to confirm these preliminary findings since the present study is limited by the retrospective cross-sectional design and by its small sample size. Topics: Absorptiometry, Photon; Adolescent; Alkaline Phosphatase; Blood Glucose; Bone Density; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Finger Phalanges; Glycated Hemoglobin; Humans; Osteocalcin; Retrospective Studies | 2022 |
A rare case of a mother with gestational diabetes complicated with fulminant type 1 diabetes mellitus post-delivery.
Fulminant type 1 diabetes mellitus (FT1DM) is recognised as a novel subtype of type 1 diabetes mellitus characterised by the abrupt onset of insulin-deficient hyperglycaemia and ketoacidosis. Fulminant type 1 diabetes mellitus is known to be associated with pregnancy and had been associated with high fetal mortality. We report a case of a gestational diabetes mellitus (GDM) mother complicated with FT1DM immediately post-delivery. A 29-year-old Malay lady who was diagnosed with GDM at 19 weeks of pregnancy, underwent emergency lower segment caesarean section (EMLSCS) due to fetal distress at 36 weeks of gestation; 18 h post-EMLSCS, she developed abrupt onset Diabetic ketoacidosis (DKA) (blood glucose 33.5 mmol/L, pH 6.99, bicarbonate 3.6 mmol/L, ketone 4.4 mmol/L and HbA1c 6.1%). She received standard DKA treatment and discharged well. Her plasma C-peptide level 3 weeks later showed that she has no insulin reserve (C-peptide <33 pmol/L, fasting blood glucose (FBS) 28 mmol/L). Her pancreatic autoantibodies were negative. This case highlights that FT1DM not only can occur in pregnancy with normal glucose tolerance but can also complicate mother with GDM. Topics: Adult; Autoantibodies; Bicarbonates; Blood Glucose; C-Peptide; Cesarean Section; Diabetes Mellitus, Type 1; Diabetes, Gestational; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Insulin; Ketones; Mothers; Pregnancy | 2022 |
Diabetes-related antibody-testing is a valuable screening tool for identifying monogenic diabetes - A survey from the worldwide SWEET registry.
To evaluate access to screening tools for monogenic diabetes in paediatric diabetes centres across the world and its impact on diagnosis and clinical outcomes of children and youth with genetic forms of diabetes.. 79 centres from the SWEET diabetes registry including 53,207 children with diabetes participated in a survey on accessibility and use of diabetes related antibodies, c-peptide and genetic testing.. 73, 63 and 62 participating centres had access to c-peptide, antibody and genetic testing, respectively. Access to antibody testing was associated with higher proportion of patients with rare forms of diabetes identified with monogenic diabetes (54 % versus 17 %, p = 0.01), lower average whole clinic HbA1c (7.7[Q1,Q2: 7.3-8.0]%/61[56-64]mmol/mol versus 9.2[8.6-10.0]%/77[70-86]mmol/mol, p < 0.001) and younger age at onset (8.3 [7.3-8.8] versus 9.7 [8.6-12.7] years p < 0.001). Additional access to c-peptide or genetic testing was not related to differences in age at onset or HbA1c outcome.. Clinical suspicion and antibody testing are related to identification of different types of diabetes. Implementing access to comprehensive antibody screening may provide important information for selecting individuals for further genetic evaluation. In addition, worse overall clinical outcomes in centers with limited diagnostic capabilities indicate they may also need support for individualized diabetes management.. NCT04427189. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Mass Screening; Registries | 2022 |
Analysis of detrended fluctuation function derived from continuous glucose monitoring may assist in distinguishing latent autoimmune diabetes in adults from T2DM.
We aimed to explore the performance of detrended fluctuation function (DFF) in distinguishing patients with latent autoimmune diabetes in adults (LADA) from type 2 diabetes mellitus (T2DM) with glucose data derived from continuous glucose monitoring.. In total, 71 LADA and 152 T2DM patients were enrolled. Correlations between glucose parameters including time in range (TIR), mean glucose, standard deviation (SD), mean amplitude of glucose excursions (MAGE), coefficient of variation (CV), DFF and fasting and 2-hour postprandial C-peptide (FCP, 2hCP) were analyzed and compared. Receiver operating characteristics curve (ROC) analysis and 10-fold cross-validation were employed to explore and validate the performance of DFF in diabetes classification respectively.. Patients with LADA had a higher mean glucose, lower TIR, greater SD, MAGE and CV than those of T2DM (. A more violent glucose fluctuation pattern was marked in patients with LADA than T2DM. We first proposed the possible role of DFF in distinguishing patients with LADA from T2DM in our study population, which may assist in diabetes classification. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Intolerance; Humans; Latent Autoimmune Diabetes in Adults | 2022 |
Routine Islet Autoantibody Testing in Clinically Diagnosed Adult-Onset Type 1 Diabetes Can Help Identify Misclassification and the Possibility of Successful Insulin Cessation.
Recent joint American Diabetes Association and European Association for the Study of Diabetes guidelines recommend routine islet autoantibody testing in all adults newly diagnosed with type 1 diabetes. We aimed to assess the impact of routine islet autoantibody testing in this population.. We prospectively assessed the relationship between islet autoantibody status (GADA, IA-2A, and ZNT8A), clinical and genetic characteristics, and progression (annual change in urine C-peptide-to-creatinine ratio [UCPCR]) in 722 adults (≥18 years old at diagnosis) with clinically diagnosed type 1 diabetes and diabetes duration <12 months. We also evaluated changes in treatment and glycemia over 2 years after informing participants and their clinicians of autoantibody results.. Of 722 participants diagnosed with type 1 diabetes, 24.8% (179) were autoantibody negative. This group had genetic and C-peptide characteristics suggestive of a high prevalence of nonautoimmune diabetes: lower mean type 1 diabetes genetic risk score (islet autoantibody negative vs. positive: 10.85 vs. 13.09 [P < 0.001] [type 2 diabetes 10.12]) and lower annual change in C-peptide (UCPCR), -24% vs. -43% (P < 0.001).After median 24 months of follow-up, treatment change occurred in 36.6% (60 of 164) of autoantibody-negative participants: 22.6% (37 of 164) discontinued insulin, with HbA1c similar to that of participants continuing insulin (57.5 vs. 60.8 mmol/mol [7.4 vs. 7.7%], P = 0.4), and 14.0% (23 of 164) added adjuvant agents to insulin.. In adult-onset clinically diagnosed type 1 diabetes, negative islet autoantibodies should prompt careful consideration of other diabetes subtypes. When routinely measured, negative antibodies are associated with successful insulin cessation. These findings support recent recommendations for routine islet autoantibody assessment in adult-onset type 1 diabetes. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Insulin; Insulin, Regular, Human | 2022 |
The continuous spectrum of glycaemic variability changes with pancreatic islet function: A multicentre cross-sectional study in China.
To investigate glycaemic variability (GV) patterns in patients with type 1 diabetes (T1D), type 2 diabetes (T2D), and latent autoimmune diabetes in adults (LADA).. A total of 842 subjects (510 T1D, 105 LADA, 227 T2D) were enrolled and underwent 1 week of continuous glucose monitoring (CGM). Clinical characteristics and CGM parameters were compared among T1D, LADA, and T2D. LADA patients were divided into two subgroups based on glutamic acid decarboxylase autoantibody titres (≥180 U/mL [LADA-1], <180 U/mL [LADA-2]) and compared. The C-peptide cut-offs for predicting a coefficient of variation (CV) of glucose ≥36% and a time in range (TIR) > 70% were determined using receiver operating characteristic analysis.. Twenty-seven patients (9 T1D, 18 T2D) were excluded due to insufficient CGM data. Sex, diabetes duration and HbA1c were comparable among the three groups. Fasting and 2-h postprandial C-peptide (FCP, 2hCP) increased sequentially across T1D, LADA, and T2D. T1D and LADA patients had comparable TIR and GV, whereas those with T2D had much higher TIR and lower GV (p < 0.001). The GV of LADA-1 was close to that of T1D, while the GV of LADA-2 was close to that of T2D. CP exhibited the strongest negative correlation with GV. The cut-offs of FCP/2hCP for predicting a CV ≥ 36% and TIR >70% were 121.6/243.1 and 128.9/252.8 pmol/L, respectively.. GV presented a continuous spectrum across T1D, LADA-1, LADA-2, and T2D. More frequent glucose monitoring is suggested for patients with impaired insulin secretion.. Chinese Clinical Trial Registration (ChiCTR) website approved by WHO; http://www.chictr.org.cn/ - ChiCTR2200065036. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Islets of Langerhans; Latent Autoimmune Diabetes in Adults | 2022 |
The course of C-peptide levels in patients developing diabetes during anti-PD-1 therapy.
Immune checkpoint inhibitor (ICI) associated diabetes is a harmful adverse event (AE) in patients with cancer following anti-programmed (cell) death protein-1 (PD-1) treatment. There are no available biomarkers able to predict this AE. The primary aim of this study was to investigate C-peptide levels as potential predictor for the occurrence of ICI-related diabetes. The secondary aim was to describe the presence of islet autoantibodies and course of pancreatic enzymes in patients with and without ICI-related diabetes.. From a total of 1318 patients with cancer who started anti-PD-1 treatment 8 cases and 16 controls were studied in this nested case-control study. C-peptide levels, islet autoantibodies, and pancreatic enzymes were measured in prospectively collected blood serum.. In cases versus controls, median C-peptide levels were comparable at baseline and before toxicity or at the corresponding time point in controls. No patient had C-peptide levels below reference range before toxicity onset. Two out of eight patients in the ICI-related diabetes group had positive islet autoantibodies, whereas one out of 16 patients in the control group had positive islet autoantibodies. Pancreatic enzymes were elevated before diabetes onset in one patient (13%) and in one control (6%) at the corresponding time point.. In patients developing ICI-related diabetes, changes in C-peptide levels, islet autoantibody positivity, and pancreatic enzymes before ICI-related diabetes onset seem comparable to patients without ICI-related diabetes. (NTR: NL6828). Topics: Autoantibodies; C-Peptide; Case-Control Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Neoplasms | 2022 |
The Bright Side of Skin Autofluorescence Determination in Children and Adolescents with Newly Diagnosed Type 1 Diabetes Mellitus: A Potential Predictor of Remission?
Skin autofluorescence (SAF) is a noninvasive method reflecting tissue accumulation of advanced glycation end products (AGEs). We investigated whether, in newly diagnosed children and adolescents with type 1 diabetes (T1D), this surrogate marker of long-term glycemia is associated with markers of the early manifestation phase, residual secretion capacity of the ß-cells, and the occurrence of remission. SAF was measured in 114 children and adolescents (age: 8.0 ± 4.5 years, 44% girls) at the time of T1D diagnosis, and related to HbA1c, C-peptide, diabetic ketoacidosis, and remission. 56 patients were followed up for 1 year. Seventy-four sex- and age-matched healthy individuals served as controls. SAF was higher in the T1D group compared with controls (1.0 ± 0.2 vs. 0.9 ± 0.2, Topics: Adolescent; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Glycation End Products, Advanced; Humans; Male; Skin | 2022 |
Persistence of β-Cell Responsiveness for Over Two Years in Autoantibody-Positive Children With Marked Metabolic Impairment at Screening.
We studied longitudinal differences between progressors and nonprogressors to type 1 diabetes with similar and substantial baseline risk.. Changes in 2-h oral glucose tolerance test indices were used to examine variability in diabetes progression in the Diabetes Prevention Trial-Type 1 (DPT-1) study (n = 246) and Type 1 Diabetes TrialNet Pathway to Prevention study (TNPTP) (n = 503) among autoantibody (Ab)+ children (aged <18.0 years) with similar baseline metabolic impairment (DPT-1 Risk Score [DPTRS] of 6.5-7.5), as well as in TNPTP Ab- children (n = 94).. Longitudinal analyses revealed annualized area under the curve (AUC) of C-peptide increases in nonprogressors versus decreases in progressors (P ≤ 0.026 for DPT-1 and TNPTP). Vector indices for AUC glucose and AUC C-peptide changes (on a two-dimensional grid) also differed significantly (P < 0.001). Despite marked baseline metabolic impairment of nonprogressors, changes in AUC C-peptide, AUC glucose, AUC C-peptide-to-AUC glucose ratio (AUC ratio), and Index60 did not differ from Ab- relatives during follow-up. Divergence between nonprogressors and progressors occurred by 6 months from baseline in both cohorts (AUC glucose, P ≤ 0.007; AUC ratio, P ≤ 0.034; Index60, P < 0.001; vector indices of change, P < 0.001). Differences in 6-month change were positively associated with greater diabetes risk (respectively, P < 0.001, P ≤ 0.019, P < 0.001, and P < 0.001) in DPT-1 and TNPTP, except AUC ratio, which was inversely associated with risk (P < 0.001).. Novel findings show that even with similarly abnormal baseline risk, progressors had appreciably more metabolic impairment than nonprogressors within 6 months and that the measures showing impairment were predictive of type 1 diabetes. Longitudinal metabolic patterns did not differ between nonprogressors and Ab- relatives, suggesting persistent β-cell responsiveness in nonprogressors. Topics: Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease Progression; Glucose; Glucose Tolerance Test; Humans | 2022 |
Preventing type 1 diabetes in late-stage pre-diabetic NOD mice with insulin: A central role for alum as adjuvant.
Restoration of immune tolerance to disease-relevant antigens is an appealing approach to prevent or arrest an organ-specific autoimmune disease like type 1 diabetes (T1D). Numerous studies have identified insulin as a key antigen of interest to use in such strategies, but to date, the success of these interventions in humans has been inconsistent. The efficacy of antigen-specific immunotherapy may be enhanced by optimising the dose, timing, and route of administration, and perhaps by the inclusion of adjuvants like alum. The aim of our study was to evaluate the effect of an insulin peptide vaccine formulated with alum to prevent T1D development in female non-obese diabetic (NOD) mice when administered during late-stage pre-diabetes.. Starting at 10 weeks of age, female NOD mice received four weekly subcutaneous injections of an insulin B:8-24 (InsB:8-24) peptide with (Ins+alum) or without Imject. InsB:8-24 peptide formulated in alum reduced diabetes incidence (39%), compared to mice receiving the InsB:8-24 peptide without alum (71%, P < 0.05), mice receiving alum alone (76%, P < 0.01), or mice left untreated (70%, P < 0.01). This was accompanied by reduced insulitis severity, and preservation of C-peptide. Ins+alum was associated with reduced frequencies of pathogenic effector memory CD4. An InsB:8-24 peptide vaccine prevented the onset of T1D in late-stage pre-diabetic NOD mice, but only when formulated in alum. These findings support the use of alum as adjuvant to optimise the efficacy of antigen-specific immunotherapy in future trials. Topics: Animals; C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Female; Forkhead Transcription Factors; Humans; Infant, Newborn; Insulin; Mice; Mice, Inbred NOD; Mice, Obese; Peptides; Prediabetic State | 2022 |
Triple drug therapy with GABA, sitagliptin, and omeprazole prevents type 1 diabetes onset and promotes its reversal in non-obese diabetic mice.
Previous studies have reported that dual drug combinations consisting of γ-aminobutyric acid (GABA) together with a dipeptidyl-peptidase-4 inhibitor (DPP-4i), also a DPP-4i with a proton pump inhibitor (PPI), could improve pancreatic β-cell function and ameliorate diabetes in diabetic mice. In this study, we sought to determine if a triple drug combination of GABA, a DPP-4i and a PPI might have superior therapeutic effects compared with double drug therapies in the prevention and reversal of diabetes in the non-obese diabetic (NOD) mouse model of human type 1 diabetes (T1D). In a diabetes prevention arm of the study, the triple drug combination of GABA, a DPP-4i, and a PPI exhibited superior therapeutic effects in preventing the onset of diabetes compared with all the double drug combinations and placebo. Also, the triple drug combination significantly increased circulating C-peptide and serum insulin levels in the mice. In a diabetes reversal arm of the study, the triple drug combination was superior to all of the double drug combinations in reducing hyperglycemia in the mice. In addition, the triple drug combination was the most effective in increasing circulating levels of C-peptide and serum insulin, thereby significantly reducing exogenous insulin needs. The combination of GABA, a DPP-4i and a PPI appears to be a promising and easily scalable therapy for the treatment and prevention of T1D. Topics: Animals; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Dipeptidyl-Peptidase IV Inhibitors; gamma-Aminobutyric Acid; Hypoglycemic Agents; Mice; Mice, Inbred NOD; Omeprazole; Proton Pump Inhibitors; Sitagliptin Phosphate | 2022 |
Pregnancy induces pancreatic insulin secretion in women with long-standing type 1 diabetes.
Pregnancy entails both pancreatic adaptations with increasing β-cell mass and immunological alterations in healthy women. In this study, we have examined the effects of pregnancy on β-cell function and immunological processes in long-standing type 1 diabetes (L-T1D).. Fasting and stimulated C-peptide were measured after an oral glucose tolerance test in pregnant women with L-T1D (n=17) during the first trimester, third trimester, and 5-8 weeks post partum. Two 92-plex Olink panels were used to measure proteins in plasma. Non-pregnant women with L-T1D (n=30) were included for comparison.. Fasting C-peptide was detected to a higher degree in women with L-T1D during gestation and after parturition (first trimester: 64.7%, third trimester: 76.5%, and post partum: 64.7% vs 26.7% in non-pregnant women). Also, total insulin secretion and peak C-peptide increased during pregnancy. The plasma protein levels in pregnant women with L-T1D was dynamic, but few analytes were functionally related. Specifically, peripheral levels of prolactin (PRL), prokineticin (PROK)-1, and glucagon (GCG) were elevated during gestation whereas levels of proteins related to leukocyte migration (CCL11), T cell activation (CD28), and antigen presentation (such as CD83) were reduced.. In summary, we have found that some C-peptide secretion, that is, an indirect measurement of endogenous insulin production, is regained in women with L-T1D during pregnancy, which might be attributed to elevated peripheral levels of PRL, PROK-1, or GCG. Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Insulin, Regular, Human; Pregnancy | 2022 |
Vitamin D Repletion and AA/EPA Intake in Children with Type 1 Diabetes: Influences on Metabolic Status.
Our study aimed to show a relationship between metabolic control, vitamin D status (25OHD), and arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio in children with type 1 diabetes (T1D). The secondary aim was to evaluate dietary intake and the presence of ketoacidosis (DKA) at the onset of T1D. Methods: A cohort of 40 children with T1D was recruited, mean age 9.7 years (7.1; 13), with onset of T1D in the last 5 years: some at onset (n: 20, group A) and others after 18.0 ± 5 months (n: 20; group B). Twenty healthy children were compared as control subjects (CS). Dietary intakes were assessed through a diary food frequency questionnaire. Moreover, dried blood spots were used to test AA/EPA ratio by gas chromatography. Results: T1D children had a lower percentage of sugar intake (p < 0.02) than CS. Furthermore, group B introduced a greater amount of AA with the diet (g/day; p < 0.05) than CS (p < 0.01) and group A (p < 0.01). Children with an AA/EPA ratio ≤ 22.5 (1st quartile) required a lower insulin demand and had higher 25OHD levels than those who were in the higher quartiles (p < 0.05). Subjects with DKA (9/40) had levels of 25OHD (p < 0.05) and C-peptide (p < 0.05) lower than those without DKA. Moreover, analyzing the food questionnaire in group A, subjects with DKA showed a lower intake of proteins, sugars, fiber (g/day; p< 0.05), vitamin D, EPA, and DHA (g/day; p < 0.01) compared to subjects without DKA. Non-linear associations between vitamin D intake (p < 0.0001; r2:0.580) and linear between EPA intake and C-peptide (p < 0.05; r: 0.375) were found in all subjects. Conclusions: The study shows a relationship between vitamin D status, AA/EPA ratio, and metabolic state, probably due to their inflammatory and immune mechanisms. A different bromatological composition of the diet could impact the severity of the onset. Topics: Arachidonic Acid; C-Peptide; Child; Diabetes Mellitus, Type 1; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Humans; Vitamin D; Vitamins | 2022 |
Higher risk of severe hypoglycemia in children and adolescents with a rapid loss of C-peptide during the first 6 years after type 1 diabetes diagnosis.
The progression to insulin deficiency in type 1 diabetes is heterogenous. This study aimed to identify early characteristics associated with rapid or slow decline of beta-cell function and how it affects the clinical course.. Stimulated C-peptide was assessed by mixed meal tolerance test in 50 children (<18 years) during 2004-2017, at regular intervals for 6 years from type 1 diabetes diagnosis. 40% of the children had a rapid decline of stimulated C-peptide defined as no measurable C-peptide (<0.03 nmol/L) 30 months after diagnosis.. At diagnosis, higher frequencies of detectable glutamic acid decarboxylase antibodies (GADA) and IA-2A (p=0.027) were associated with rapid loss of beta-cell function. C-peptide was predicted positively by age at 18 months (p=0.017) and 30 months duration (p=0.038). BMI SD scores (BMISDS) at diagnosis predicted higher C-peptide at diagnosis (p=0.006), 3 months (p=0.002), 9 months (p=0.005), 30 months (p=0.022), 3 years (p=0.009), 4 years (p=0.016) and 6 years (p=0.026), whereas high HbA1c and blood glucose at diagnosis predicted a lower C-peptide at diagnosis (p=<0.001) for both comparisons. Both GADA and IA-2A were negative predictors of C-peptide at 9 months (p=0.011), 18 months (p=0.008) and 30 months (p<0.001). Ten children had 22 events of severe hypoglycemia, and they had lower mean C-peptide at 18 months (p=0.025), 30 months (p=0.008) and 6 years (p=0.018) compared with others. Seven of them had a rapid decline of C-peptide (p=0.030), and the odds to experience a severe hypoglycemia were nearly fivefold increased (OR=4.846, p=0.04).. Low age and presence of multiple autoantibodies at diagnosis predicts a rapid loss of beta-cell function in children with type 1 diabetes. Low C-peptide is associated with an increased risk of severe hypoglycemia and higher Hemoglobin A1C. A high BMISDS at diagnosis is predictive of remaining beta-cell function during the 6 years of follow-up. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Hypoglycemia; Infant; Insulin | 2022 |
Immunological markers in type 1 diabetes mellitus in Thi-Qar province, southern Iraq.
Type 1 diabetes mellitus (T1D) is a chronic autoimmune illness defined as insulin insufficiency resulting from the autoimmune breakdown of pancreatic beta cells producing insulin in the islets of Langerhans. Biomarkers are markers of physiological or pathological processes that are normal or abnormal, playing a crucial function in clinical evaluation, prognosis, and therapy response monitoring. This study aimed to investigate some biomarkers associated with T1D and examine the association between glutamic acid carboxylase (GADA) antibody and islet antigen-2 autoantibody (IA-2A) for β-cell stress and death in patients with T1D. The current study included 60 patients with T1D, 32 (53.33%) males and 28 (46.67%) females between 9 to 18 years old, and 30 healthy individuals as control. Glutamic acid carboxylase, islet antigen-2 autoantibody and connecting peptide levels in the blood were evaluated. Positive results for IA-2A and GADA were shown in 89.04% and 38% of T1D patients, respectively. The normal level frequency and C-peptide titer mean were significantly lower between T1D and healthy control. However, no statistically significant changes were observed in the C-peptide level among GADA positive and negative patients. Finally, the C-peptide concentrations were significantly lower for positive IA-2A compared to negative IA-2A persons. The combination of IA-2A, GADA, and C-peptide could indicate stronger diagnostic measures at a low cost for patients with T1D. Topics: Adolescent; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glutamic Acid; Humans; Iraq; Male | 2022 |
Combination therapy with lansoprazole and cholecalciferol is associated with a slower decline in residual beta-cell function and lower insulin requirements in children with recent onset type 1 diabetes: results of a pilot study.
To investigate the effects of combination therapy with cholecalciferol and lansoprazole on residual β-cell function and glycemic control in children with new-onset type 1 diabetes.. Children aged 6-12 years with type 1 diabetes were allocated to receive cholecalciferol and lansoprazole (Group 1) or no treatment (Group 2). Children were maintained on their respective insulin regimens and kept records of blood sugar and insulin doses taken. Children were followed at three-month intervals for six months. Changes in mean fasting C-peptide and HbA1c levels, daily insulin doses, fasting blood glucose and mean blood glucose levels from baseline to end of the study were analyzed.. Twenty-eight children (14 per group) met the eligibility criteria. Fasting C-peptide levels decreased significantly from baseline to study end in both groups (mean decrease -0.19±0.09ng/mL and -0.28±0.08ng/mL, p=0.04 and p=0.001; Group 1 and Group 2 respectively). However, fasting C-peptide level drop was significantly smaller in Group 1 compared to Group 2 (30.6% and 47.5% respectively; p=0.001). Likewise, daily insulin doses decreased significantly in both groups (-0.59±0.14units/kg and -0.37±0.24units/kg respectively; p=0.001). All patients recruited completed the study. No adverse events were reported.. Combined therapy with cholecalciferol and lansoprazole for six months was associated with smaller decline in residual β-cell function and lower insulin requirements in children with new-onset type 1 diabetes. Preliminary findings of this small-scale study need to be confirmed by larger studies.. (www.ctri.nic.in) under number REF/2021/03/041415 N. Topics: Blood Glucose; C-Peptide; Child; Cholecalciferol; Diabetes Mellitus, Type 1; Disease Progression; Humans; Insulin; Lansoprazole; Pilot Projects | 2022 |
CLINICAL AND IMMUNOLOGICAL PROFILE OF NEWLY DIAGNOSED DIABETIC PATIENTS IN A COHORT OF YOUNG ADULTS OF NATIONAL HEPATITIS C VIRUS SURVEY IN EGYPT.
T2DM (Type 2 diabetes mellitus) is considered a disease that affects old age group. Recently, it has become common in children, adolescents and adults. Aim of the work - to highlight the challenges in differentiating T1DM (type1 diabetes mellitus) from T2DM (type2 diabetes mellitus) in early onset diabetes in youth depending on clinical and laboratory characteristics. Our cross-sectional study was performed on 200 newly diagnosed diabetic patients aged (18-30) years. All patients were subjected to detailed medical history and full clinical examination. Laboratory investigations included FBS, 2hPP, HbA1C, fasting C peptide and GADA. About 59% (118) of our patients were T2DM while (82) 41% were T1DM. T1DM was more dominant than T2DM in age group less than 25 years (T1DM 79% versus T2DM 21%, P<0.001), while T2DM was more than T1DM in age group more than 25 years (T2DM 93% versus T1DM 17%, P<0.001). GADA was detected in 73.2% of T1DM patient and it was high titer while GADA was detected in only 8% of T2DM with low titer, in addition GADA positive patients were significantly younger than negative patients, age (20.9±2.5 years vs. 26.4±3.5 years respectively) (P <0.001). About 8% of phenotypically type 2 diabetic youth had GADA positive antibodies which did not confer impact on c peptide level or glycemic control yet type 1 diabetics who were GADA negative had a better glycemic control. Topics: Adolescent; Autoantibodies; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Egypt; Hepacivirus; Humans; Young Adult | 2022 |
Response to comment on 'impact of routine clinic measurement of random serum C-peptide in people with a clinician diagnosis of type 1 diabetes' doi: 10.1111/dme.14449.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Humans | 2022 |
Rapid Point-of-Care Test for Determination of C-Peptide Levels.
C-peptide is co-secreted with insulin and is not subject to hepatic clearance and thus reflects functional β-cell mass. Assessment of C-peptide levels can identify individuals at risk for or with type 1 diabetes with residual β-cell function in whom β cell-sparing interventions can be evaluated, and can aid in distinguishing type 2 diabetes from Latent Autoimmune Diabetes in Adults and late-onset type 1 diabetes. To facilitate C-peptide testing, we describe a quantitative point-of-care C-peptide test. C-peptide levels as low as 0.2 ng/ml were measurable in a fingerstick sample, and the test was accurate over a range of 0.17 to 12.0 ng/ml. This test exhibited a correlation of Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Point-of-Care Testing | 2022 |
Prevalence and clinical characteristics of fulminant type 1 diabetes mellitus in Korean adults: A multi-institutional joint research.
We aimed to determine the hospital-based prevalence and clinical features of fulminant type 1 diabetes mellitus in Korea.. We identified all patients with diabetes who regularly visited the Endocrinology outpatient clinics at eight centers for a period >1 year between January 2012 and June 2017. We investigated their medical records retrospectively.. During this period, 76,309 patients with diabetes had been regularly followed up. Among them, 913 (1.2%) patients had type 1 diabetes mellitus . There were 462 patients with type 1 diabetes mellitus whose data at the time of the first diagnosis could be identified (359 and 103 with non-ketosis and ketosis onset, respectively). Of these, 15 (3.2% of type 1 diabetes mellitus, 14.6% of ketosis onset diabetes) patients had fulminant type 1 diabetes mellitus. The median ages at diagnosis were 40 and 27 years in the fulminant type 1 diabetes mellitus and non-fulminant type 1 diabetes mellitus groups, respectively. The patients with fulminant type 1 diabetes mellitus had higher body mass index, lower glycated hemoglobin and fasting/peak C-peptide, and lower frequent glutamic acid decarboxylase antibody-positive rate (P =0.0010) at diagnosis. Furthermore, they had lower glycated hemoglobin at the last follow-up examination than those with non-fulminant type 1 diabetes mellitus.. In this study, the prevalence of type 1 diabetes mellitus was 1.2% among all patients with diabetes, and that of fulminant type 1 diabetes mellitus was 3.2% among those newly diagnosed with type 1 diabetes mellitus. The glycated hemoglobin levels were lower in patients with fulminant type 1 diabetes mellitus than in those with non-fulminant type 1 diabetes mellitus at diagnosis and at the last follow-up examination. Topics: Adult; Asian People; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Male; Middle Aged; Prevalence; Republic of Korea; Retrospective Studies | 2022 |
The impact of islet mass, number of transplants, and time between transplants on graft function in a national islet transplant program.
The UK islet allotransplant program is nationally funded to deliver one or two transplants over 12 months to individuals with type 1 diabetes and recurrent severe hypoglycemia. Analyses were undertaken 10 years after program inception to evaluate associations between transplanted mass; single versus two transplants; time between two transplants and graft survival (stimulated C-peptide >50 pmol/L) and function. In total, 84 islet transplant recipients were studied. Uninterrupted graft survival over 12 months was attained in 23 (68%) single and 47 (94%) (p = .002) two transplant recipients (separated by [median (IQR)] 6 (3-8) months). 64% recipients of one or two transplants with uninterrupted function at 12 months sustained graft function at 6 years. Total transplanted mass was associated with Mixed Meal Tolerance Test stimulated C-peptide at 12 months (p < .01). Despite 1.9-fold greater transplanted mass in recipients of two versus one islet infusion (12 218 [9291-15 417] vs. 6442 [5156-7639] IEQ/kg; p < .0001), stimulated C-peptide was not significantly higher. Shorter time between transplants was associated with greater insulin dose reduction at 12 months (beta -0.35; p = .02). Graft survival over the first 12 months was greater in recipients of two versus one islet transplant in the UK program, although function at 1 and 6 years was comparable. Minimizing the interval between 2 islet infusions may maximize cumulative impact on graft function. Topics: C-Peptide; Diabetes Mellitus, Type 1; Graft Survival; Humans; Insulin; Islets of Langerhans Transplantation | 2022 |
Residual C-peptide secretion and hypoglycemia awareness in people with type 1 diabetes.
This study aimed to assess the association between fasting serum C-peptide levels and the presence of impaired awareness of hypoglycemia (IAH) in people with type 1 diabetes.. We performed a cross-sectional study among 509 individuals with type 1 diabetes (diabetes duration 5-65 years). Extensive clinical data and fasting serum C-peptide concentrations were collected and related to the presence or absence of IAH, which was evaluated using the validated Dutch version of the Clarke questionnaire. A multivariable logistic regression model was constructed to investigate the association of C-peptide and other clinical variables with IAH.. In 129 (25%) individuals, residual C-peptide secretion was detected, while 75 (15%) individuals reported IAH. The median (IQR) C-peptide concentration among all participants was 0.0 (0.0-3.9) pmol/L. The prevalence of severe hypoglycemia was lower in people with demonstrable C-peptide versus those with absent C-peptide (30% vs 41%, p=0.025). Individuals with IAH were older, had longer diabetes duration, more frequently had macrovascular and microvascular complications, and more often used antihypertensive drugs, antiplatelet agents and cholesterol-lowering medication. There was a strong association between IAH and having a severe hypoglycemia in the preceding year. In multivariable regression analysis, residual C-peptide, either continuously or dichotomous, was associated with lower prevalence of IAH (p=0.040-0.042), while age at diabetes onset (p=0.001), presence of microvascular complications (p=0.003) and body mass index (BMI) (p=0.003) were also independently associated with the presence of IAH.. Higher BMI, the presence of microvascular complications and higher age at diabetes onset were independent risk factors for IAH in people with type 1 diabetes, while residual C-peptide secretion was associated with lower risk of this complication. Topics: C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Humans; Hypoglycemia; Surveys and Questionnaires | 2021 |
A case of Graves' disease and type 1 diabetes mellitus following SARS-CoV-2 vaccination.
Autoimmune diseases, including autoimmune endocrine diseases (AIED), are thought to develop following environmental exposure in patients with genetic predisposition. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and vaccines against it could represent new environmental triggers for AIED. We report a patient, with history of vitiligo vulgaris and 8 years of type 2 diabetes, who came to our institution because of fever, weight loss, asthenia and thyrotoxicosis occurred 4 weeks later the administration of BNT162B2 (Pfizer-BioNTech) SARS-CoV-2 vaccine. Clinical, biochemical and instrumental work-up demonstrated Graves' disease and autoimmune diabetes mellitus. The occurrence of these disorders could be explained through different mechanism such as autoimmune/inflammatory syndrome induced by adjuvants (ASIA syndrome), mRNA "self-adjuvant" effect, molecular mimicry between human and viral proteins and immune disruption from external stimuli. However further studies are needed to better understand the underlying pathogenesis of AIED following SARS-CoV-2 vaccine. Topics: Adjuvants, Immunologic; Autoantibodies; BNT162 Vaccine; C-Peptide; COVID-19; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Glycemic Control; Graves Disease; Humans; Male; Middle Aged; Molecular Mimicry; SARS-CoV-2; Thyrotoxicosis; Vitiligo | 2021 |
Impact of COVID-19 on new-onset type 1 diabetes mellitus - A one-year prospective study.
A positive relationship between the recently emerged Corona Virus Disease-19 (COVID-19) and diabetes has been inferred, but not confirmed, in children. The aim of the present study was to investigate the possible impact of COVID-19 on new-onset Type-1 Diabetes Mellitus (T1DM) in a pediatric population.. This is a prospective study of all children and adolescents diagnosed with T1DM during the first year of the COVID-19 pandemic (March 2020-February 2021) in Western Greece (population coverage ≈1,000,000). The incidence and severity of T1DM, the age and sex of the participants and HbA1c and c-peptide concentrations at diagnosis were recorded and compared to those of the previous year (pre-COVID-19 year).. 21 children aged 8.03±0.90 years old were diagnosed with T1DM in the COVID-19 year and 17, aged 9.44±3.72 years old, in the pre-COVID-19 year. A different seasonality pattern of new onsets was observed during the COVID-19 year compared to the previous year, with increasing trend from spring to winter (spring: 9.5% vs. 23.5%, autumn: 23.8% vs. 29.4%, summer: 19% vs. 11.8%, winter: 47.6% vs. 35.3%). Also, compared to the preceding year, HbA1c was significantly higher (p=0.012) and the incidence and severity of diabetic ketoacidosis greater (p=0.045, p=0.013, respectively).. This is the first study to report a different seasonality pattern and increased severity of new-onset T1DM during the first year of the COVID-19 pandemic. Future research should further investigate the possible role of SARS-CoV-2 and the different pattern of overall infection incidence during the COVID-19 year. Topics: Adolescent; C-Peptide; Child; Child, Preschool; COVID-19; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Greece; Humans; Incidence; Male; Prospective Studies; Seasons | 2021 |
[Advanced glycation end products and oxidative stress as a basis for metabolic abnormalities in patients with type 1 diabetes after successful simultaneous pancreas-kidney transplantation].
To compare advanced glycation end-products (AGE, RAGE) and 3-nitrotyrosine (3-HT) in patients with DM 1 after successful simultaneous pancreas-kidney transplantation (SPK) and kidney transplantation alone (KTA). To assess relationship between levels of AGE, RAGE, 3-HT and renal transplant (RT) function, carbohydrate and mineral metabolism.. The study included 58 patients who received kidney transplantation in end-stage renal disease (ESRD). 36 patients received SPK. There were performed routine laboratory, examination of AGE, RAGE, 3-NT, parathyroid hormone (PTH), 25(OH)vitamin D, calcium, phosphorus, FGF23, osteoprotegerin (OPG), and fetuin-A levels.. All patients after SPK reached normoglycemia (HbA1c 5.7 [5.3; 6.1] %; C-peptide 3.24 [2.29; 4.40] ng/ml) with the achievement of significant difference vs patients after KTA. Arterial hypertension (AH) was more frequent in recipients of SPK before transplantation than after (p=0.008). AH also persisted in greater number of cases in patients after KTA than after SPK. Patients after SPK had higher AGE (р=0.0003) and lower RAGE (р=0.000003) levels. OPG in patients after SPK was significantly higher (р=0.04). The correlation analysis revealed significant positive correlation between 3-HT and OPG (p0.05; r=0.30), RAGE and eGFR (r=-0.52), HbA1c (r=0.48), duration of AH (r=0.34), AGE with HbA1c (r=0.51).. The results of the "metabolic memory" markers analysis may indicate their contribution to the persistence of the metabolic consequences of CKD and DM 1 after achievement of normoglycemia and renal function restoration and their possible participation in development of recurrent nephropathy, vascular calcification, and bone disorders.. Цель. Сравнить состояние конечных продуктов гликирования (AGE, RAGE) и 3-нитротирозина (3-НТ) у пациентов с сахарным диабетом 1-го типа после успешной сочетанной трансплантации почки и поджелудочной железы (СТПиПЖ), изолированной трансплантации почки (ИТП). Оценить взаимосвязь уровней AGE, RAGE, 3-НТ с функцией ренального трансплантата, состоянием углеводного и минерального обмена. Материалы и методы. В исследование включили 58 пациентов после трансплантации почки по поводу терминальной стадии хронической болезни почек (36 реципиентов после СТПиПЖ). Всем больным проводились клинико-лабораторное обследование, определение уровней AGE, RAGE, 3-НТ, паратгормона, 25(ОН)витамина D, FGF23, остеопротегерина (ОПГ) и фетуина А. Результаты. У пациентов после СТПиПЖ наблюдалась нормогликемия (гликированный гемоглобин HbA1c 5,7 [5,3; 6,1] %; С-пептид 3,24 [2,29; 4,40] нг/мл) с достижением значимой разницы при сравнении с больными после ИТП. Артериальная гипертензия (АГ) значимо чаще наблюдалась у реципиентов СТПиПЖ до трансплантации, чем после (р=0,008), у больных после ИТП АГ также сохранялась чаще, чем у пациентов после СТПиПЖ. Соответственно, больные после СТПиПЖ гораздо реже нуждались в антигипертензивной терапии (р=0,001). Уровень AGE был значимо выше (р=0,0003), RAGE значимо ниже (р=0,000003) у пациентов после СТПиПЖ, ОПГ значимо больше у реципиентов СТПиПЖ (р=0,04). Обнаружена положительная корреляция 3-НТ с ОПГ (p0,05; r=0,30), RAGE с расчетной скоростью клубочковой фильтрации (r=-0,52), HbA1c (r=0,48), длительностью АГ (r=0,34), AGE с HbA1c (r=0,51). Заключение. Результаты анализа маркеров метаболической памяти могут отражать их вклад в персистенцию метаболических последствий хронической болезни почек и сахарного диабета 1-го типа после достижения нормогликемии и восстановления почечной функции после СТПиПЖ, участие в развитии возвратной нефропатии, сосудистой кальцификации и костных нарушений. Topics: alpha-2-HS-Glycoprotein; C-Peptide; Calcium; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Glycation End Products, Advanced; Graft Survival; Humans; Kidney Transplantation; Minerals; Osteoprotegerin; Oxidative Stress; Pancreas; Pancreas Transplantation; Parathyroid Hormone; Phosphorus; Vitamin D | 2021 |
Fasting parameters for estimation of stimulated β cell function in islet transplant recipients with or without basal insulin treatment.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation | 2021 |
Invincible β-cells in type 1 diabetes.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells | 2021 |
Relationships between Islet-Specific Autoantibody Titers and the Clinical Characteristics of Patients with Diabetes Mellitus.
Dysimmunity plays a key role in diabetes, especially type 1 diabetes mellitus. Islet-specific autoantibodies (ISAs) have been used as diagnostic markers for different phenotypic classifications of diabetes. This study was aimed to explore the relationships between ISA titers and the clinical characteristics of diabetic patients.. A total of 509 diabetic patients admitted to Department of Endocrinology and Metabolism at the Affiliated Hospital of Nantong University were recruited. Anthropometric parameters, serum biochemical index, glycosylated hemoglobin, urinary microalbumin/creatinine ratio, ISAs, fat mass, and islet β-cell function were measured. Multiple linear regression analysis was performed to identify relationships between ISA titers and clinical characteristics.. Compared with autoantibody negative group, blood pressure, weight, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), visceral fat mass, fasting C-peptide (FCP), 120 minutes C-peptide (120minCP) and area under C-peptide curve (AUCCP) of patients in either autoantibody positive or glutamate decarboxylase antibody (GADA) positive group were lower. Body mass index (BMI), waist circumference, triglycerides (TGs), body fat mass of patients in either autoantibody positive group were lower than autoantibody negative group. GADA titer negatively correlated with TC, LDL-C, FCP, 120minCP, and AUCCP. The islet cell antibody and insulin autoantibody titers both negatively correlated with body weight, BMI, TC, TG, and LDL-C. After adjusting confounders, multiple linear regression analysis showed that LDL-C and FCP negatively correlated with GADA titer.. Diabetic patients with a high ISA titer, especially GADA titer, have worse islet β-cell function, but less abdominal obesity and fewer features of the metabolic syndrome. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Metabolic Syndrome | 2021 |
Pregnant type 1 diabetes women with rises in C-peptide display higher levels of regulatory T cells: A pilot study.
During pregnancy of type 1 diabetes (T1D) women, a C peptide rise has been described, which mechanism is unclear. In T1D, a defect of regulatory T cells (Tregs) and its major controlling cytokine, interleukin-2 (IL2), is observed.. Evolution of clinical, immunological (Treg (CD4+CD25hiCD127-/loFoxp3+ measured by flow cytometry and IL2 measured by luminex xMAP technology) and diabetes parameters (insulin dose per day, HbA1C, glycaemia, C peptide) was evaluated in 13 T1D women during the three trimesters of pregnancy and post-partum (PP, within 6 months) in a monocentric pilot study. Immunological parameters were compared with those of a healthy pregnant cohort (QuTe).. An improvement of beta cell function (C peptide rise and/or a decrease of insulin dose-adjusted A1c index that estimate individual exogenous insulin need) was observed in seven women (group 1) whereas the six others (group 2) did not display any positive response to pregnancy. A higher level of Tregs and IL2 was observed in group 1 compared to group 2 during pregnancy and at PP for Tregs level. However, compared to the healthy cohort, T1D women displayed a Treg deficiency CONCLUSION: This pilot study highlights that higher level of Tregs and IL2 seem to allow improvement of endogenous insulin secretion of T1D women during pregnancy. Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Interleukin-2; Pilot Projects; Pregnancy; Pregnancy in Diabetics; T-Lymphocytes, Regulatory | 2021 |
Biological activity versus physiological function of proinsulin C-peptide.
Proinsulin C-peptide (C-peptide) has drawn much research attention. Even if the peptide has turned out not to be important in the treatment of diabetes, every phase of C-peptide research has changed our view on insulin and peptide hormone biology. The first phase revealed that peptide hormones can be subject to processing, and that their pro-forms may involve regulatory stages. The second phase revealed the possibility that one prohormone could harbor more than one activity, and that the additional activities should be taken into account in the development of hormone-based therapies. In the third phase, a combined view of the evolutionary patterns in hormone biology allowed an assessment of C-peptide´s role in physiology, and of how biological activities and physiological functions are shaped by evolutionary processes. In addition to this distinction, C-peptide research has produced further advances. For example, C-peptide fragments are successfully administered in immunotherapy of type I diabetes, and plasma C-peptide levels remain a standard for measurement of beta cell activity in patients. Even if the concept of C-peptide as a hormone is presently not supported, some of its bioactivities continue to influence our understanding of evolutionary changes of also other peptides. Topics: C-Peptide; Diabetes Mellitus, Type 1; Evolution, Molecular; Humans; Protein Aggregates; Protein Conformation | 2021 |
Transition of blood glucose level in a patient with pregnancy-associated fulminant type 1 diabetes mellitus.
We report on the transition in blood glucose levels before and after the onset of fulminant type 1 diabetes mellitus in a perinatal woman. In week 38 of pregnancy, before which the patient had normal glucose tolerance, idiopathic acute pancreatitis was diagnosed. Five days thereafter, she became hypoglycemic, so we closely monitored her blood glucose levels. A total of 13 days later, she was hyperglycemic with a blood glucose level >16.0 mmol/L and glycated hemoglobin of 6.4%. Her fasting serum C-peptide reactivity level was 3.6 ng/mL on the 5th day, and 0.2 ng/mL on the 18th day. Multiple insulin injection therapy was administered since the 18th day; after that, ketoacidosis did not occur. The patient was diagnosed with fulminant type 1 diabetes mellitus based on hyperglycemia without high glycated hemoglobin levels and sudden onset insulin-dependent diabetes. Monitoring glucose levels in the case of idiopathic acute pancreatitis during pregnancy and prompt initiation of insulin therapy are important. Topics: Acute Disease; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Pancreatitis; Pregnancy; Pregnancy Complications | 2021 |
Factors Associated With the Decline of C-Peptide in a Cohort of Young Children Diagnosed With Type 1 Diabetes.
Understanding factors involved in the rate of C-peptide decline is needed to tailor therapies for type 1 diabetes (T1D).. Evaluate factors associated with rate of C-peptide decline after a T1D diagnosis in young children.. Observational study.. Academic centers.. A total of 57 participants from the Environmental Determinants of Diabetes in the Young (TEDDY) study who were enrolled at 3 months of age and followed until T1D, and 56 age-matched children diagnosed with T1D in the community.. A mixed meal tolerance test was used to measure the area under the curve (AUC) C-peptide at 1, 3, 6, 12, and 24 months postdiagnosis.. Factors associated with rate of C-peptide decline during the first 2 years postdiagnosis were evaluated using mixed effects models, adjusting for age at diagnosis and baseline C-peptide.. Adjusted slopes of AUC C-peptide decline did not differ between TEDDY subjects and community controls (P = 0.21), although the former had higher C-peptide baseline levels. In univariate analyses combining both groups (n = 113), younger age, higher weight and body mass index z-scores, female sex, an increased number increased number of islet autoantibodies, and IA-2A or ZnT8A positivity at baseline were associated with a higher rate of C-peptide loss. Younger age, female sex, and higher weight z-score remained significant in multivariate analysis (all P < 0.02). At 3 months after diagnosis, higher HbA1c became an additional independent factor associated with a higher rate of C-peptide decline (P < 0.01).. Younger age at diagnosis, female sex, higher weight z-score, and HbA1c were associated with a higher rate of C-peptide decline after T1D diagnosis in young children. Topics: Adolescent; Age of Onset; Autoantibodies; C-Peptide; Case-Control Studies; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Disease Progression; Down-Regulation; Female; Follow-Up Studies; Humans; Infant; Male | 2021 |
Bone microarchitecture abnormalities in type 1 diabetes and in latent autoimmune diabetes in adults. A potential role for C-peptide.
Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Latent Autoimmune Diabetes in Adults | 2021 |
Impact of routine clinic measurement of serum C-peptide in people with a clinician-diagnosis of type 1 diabetes.
The aim of this study was to determine the impact of the routine use of serum C-peptide in an out-patient clinic setting on individuals with a clinician-diagnosis of type 1 diabetes.. In this single-centre study, individuals with type 1 diabetes of at least 3 years duration were offered random serum C-peptide testing at routine clinic review. A C-peptide ≥200 pmol/L prompted further evaluation of the individual using a diagnostic algorithm that included measurement of islet cell antibodies and genetic testing. Where appropriate, a trial of anti-diabetic co-therapies was considered.. Serum C-peptide testing was performed in 859 individuals (90% of the eligible cohort), of whom 114 (13.2%) had C-peptide ≥200 pmol/L. The cause of diabetes was reclassified in 58 individuals (6.8% of the tested cohort). The majority of reclassifications were to type 2 diabetes (44 individuals; 5.1%), with a smaller proportion of monogenic diabetes (14 individuals; 1.6%). Overall, 13 individuals (1.5%) successfully discontinued insulin, while a further 16 individuals (1.9%) had improved glycaemic control following the addition of co-therapies. The estimated total cost of the testing programme was £23,262 (~€26,053), that is, £27 (~€30) per individual tested. In current terms, the cost of prior insulin therapy in the individuals with monogenic diabetes who successfully stopped insulin was approximately £57,000 (~€64,000).. Serum C-peptide testing can easily be incorporated into an out-patient clinic setting and could be a cost-effective intervention. C-peptide testing should be strongly considered in individuals with a clinician-diagnosis of type 1 diabetes of at least 3 years duration. Topics: Adolescent; Adult; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Young Adult | 2021 |
A TCR-like antibody against a proinsulin-containing fusion peptide ameliorates type 1 diabetes in NOD mice.
Type 1 diabetes (T1D) is an autoimmune disease caused by destruction of insulin-producing β cells. The response of autoreactive T cells to β cell antigens plays a central role in the development of T1D. Recently, fusion peptides composed by insulin C-peptide fragments and other proteins were reported as β cell target antigens for diabetogenic CD4 Topics: Animals; Antibodies, Monoclonal; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Progression; Histocompatibility Antigens Class II; Mice; Mice, Inbred NOD; Proinsulin; Receptors, Antigen, T-Cell; Recombinant Fusion Proteins; T-Lymphocytes | 2021 |
Flash glucose monitoring data analysed by detrended fluctuation function on beta-cell function and diabetes classification.
We aimed to use data-driven glucose pattern analysis to unveil the correlation between the metrics reflecting glucose fluctuation and beta-cell function, and to identify the possible role of this metric in diabetes classification.. In total, 78 participants with type 1 diabetes and 59 with type 2 diabetes were enrolled in this study. All participants wore a flash glucose monitoring system, and glucose data were collected. A detrended fluctuation function (DFF) was utilized to extract glucose fluctuation information from flash glucose monitoring data and a DFF-based glucose fluctuation metric was proposed.. For the entire study population, a significant negative correlation between the DFF-based glucose fluctuation metric and fasting C-peptide was observed (r = -0.667; P <.001), which was larger than the correlation coefficient between the fasting C-peptide and mean amplitude of plasma glucose excursions (r = -0.639; P < .001), standard deviation (r = -0.649; P <.001), mean blood glucose (r = -0.519; P < .001) and time in range (r = 0.593; P < .001). As glucose data analysed by DFF revealed a clear bimodal distribution among the total participants, we randomly assigned the 137 participants into discovery cohorts (n = 100) and validation cohorts (n = 37) for 10 times to evaluate the consistency and effectiveness of the proposed metric for diabetes classification. The confidence interval for area under the curve according to the receiver operating characteristic analysis in the 10 discovery cohorts achieved (0.846, 0.868) and that for the 10 validation cohorts was (0.799, 0.862). In addition, the confidence intervals for sensitivity and specificity in the discovery cohorts were (75.5%, 83.0%), (81.3%, 88.5%) and (71.8%, 88.3%), (76.5%, 90.3%) in the validation cohorts, indicating the potential capacity of DFF in distinguishing type 1 and type 2 diabetes.. Our study first proposed the possible role of data-driven analysis acquired glucose metric in predicting beta-cell function and diabetes classification, and a large-scale, multicentre study will be needed in the future. Topics: Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans | 2021 |
Baseline Assessment of Circulating MicroRNAs Near Diagnosis of Type 1 Diabetes Predicts Future Stimulated Insulin Secretion.
Type 1 diabetes is an autoimmune disease resulting in severely impaired insulin secretion. We investigated whether circulating microRNAs (miRNAs) are associated with residual insulin secretion at diagnosis and predict the severity of its future decline. We studied 53 newly diagnosed subjects enrolled in placebo groups of TrialNet clinical trials. We measured serum levels of 2,083 miRNAs, using RNA sequencing technology, in fasting samples from the baseline visit (<100 days from diagnosis), during which residual insulin secretion was measured with a mixed meal tolerance test (MMTT). Area under the curve (AUC) C-peptide and peak C-peptide were stratified by quartiles of expression of 31 miRNAs. After adjustment for baseline C-peptide, age, BMI, and sex, baseline levels of miR-3187-3p, miR-4302, and the miRNA combination of miR-3187-3p/miR-103a-3p predicted differences in MMTT C-peptide AUC/peak levels at the 12-month visit; the combination miR-3187-3p/miR-4723-5p predicted proportions of subjects above/below the 200 pmol/L clinical trial eligibility threshold at the 12-month visit. Thus, miRNA assessment at baseline identifies associations with C-peptide and stratifies subjects for future severity of C-peptide loss after 1 year. We suggest that miRNAs may be useful in predicting future C-peptide decline for improved subject stratification in clinical trials. Topics: Adolescent; Adult; C-Peptide; Child; Circulating MicroRNA; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Male; Meals; Young Adult | 2021 |
Type 1 diabetes mellitus in patients with recurrent acute and chronic pancreatitis: A case series.
Pancreatogenic diabetes mellitus has been assumed to result from non-immune beta cell destruction when the pancreas is replaced by fibrotic tissue secondary to acute and chronic pancreatitis. We hypothesize that recurrent episodes of pancreatic inflammation may increase the risk for developing β-cell autoimmunity in susceptible individuals.. We describe 11 patients who had both recurrent acute and/or chronic pancreatitis and type 1 diabetes (T1D) requiring insulin therapy.. All 11 patients had positive autoantibodies and 8 patients tested had minimal to undetectable (7/8) or moderate (1/8) stimulated C-peptide at 12 months after T1D onset. Three had biopsy confirmation of insulitis.. These cases lend support to the theory that pancreatitis may increase risk for T1D. We postulate that the pro-inflammatory conditions of pancreatitis may increase posttranslational protein modifications of β-cell antigens and neoepitope generation, which are potential initiating events for loss of β-cell self-tolerance. Topics: Acute Disease; Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Chronic Disease; Diabetes Mellitus, Type 1; Humans; Infant; Inflammation; Middle Aged; Pancreatitis; Protein Processing, Post-Translational; Recurrence; Risk Factors; Young Adult | 2021 |
Impact of glucagon response on early postprandial glucose excursions irrespective of residual β-cell function in type 1 diabetes: A cross-sectional study using a mixed meal tolerance test.
Controlling postprandial glucose levels in patients with type 1 diabetes is challenging even under the adequate treatment of insulin injection. Recent studies showed that dysregulated glucagon secretion exacerbates hyperglycemia in type 2 diabetes patients, but little is known in type 1 diabetes patients. We investigated whether the glucagon response to a meal ingestion could influence the postprandial glucose excursion in patients with type 1 diabetes.. We enrolled 34 patients with type 1 diabetes and 23 patients with type 2 diabetes as controls. All patients underwent a liquid mixed meal tolerance test. We measured levels of plasma glucose, C-peptide and glucagon at fasting (0 min), and 30, 60 and 120 min after meal ingestion. All type 1 diabetes patients received their usual basal insulin and two-thirds of the necessary dose of the premeal bolus insulin.. The levels of plasma glucagon were elevated and peaked 30 min after the mixed meal ingestion in both type 1 diabetes and type 2 diabetes patients. The glucagon increments from fasting to each time point (30, 60 and 120 min) in type 1 diabetes patients were comparable to those in type 2 diabetes patients. Among the type 1 diabetes patients, the glucagon response showed no differences between the subgroups based on diabetes duration (<5 vs ≥5 years) and fasting C-peptide levels (<0.10 vs ≥0.10 nmol/L). The changes in plasma glucose from fasting to 30 min were positively correlated with those in glucagon, but not C-peptide, irrespective of diabetes duration and fasting C-peptide levels in patients with type 1 diabetes.. The dysregulated glucagon likely contributes to postprandial hyperglycemia independent of the residual β-cell functions during the progression of type 1 diabetes. Topics: Adult; Aged; Blood Glucose; C-Peptide; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glucose Tolerance Test; Humans; Hyperglycemia; Insulin-Secreting Cells; Male; Meals; Middle Aged; Prospective Studies | 2021 |
Comment on 'impact of routine Clinic Measurement of random Serum c-peptide in people with a Clinician Diagnosis of type 1 diabetes'.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans | 2021 |
Genetic Composition and Autoantibody Titers Model the Probability of Detecting C-Peptide Following Type 1 Diabetes Diagnosis.
We and others previously demonstrated that a type 1 diabetes genetic risk score (GRS) improves the ability to predict disease progression and onset in at-risk subjects with islet autoantibodies. Here, we hypothesized that GRS and islet autoantibodies, combined with age at onset and disease duration, could serve as markers of residual β-cell function following type 1 diabetes diagnosis. Generalized estimating equations were used to investigate whether GRS along with insulinoma-associated protein-2 autoantibody (IA-2A), zinc transporter 8 autoantibody (ZnT8A), and GAD autoantibody (GADA) titers were predictive of C-peptide detection in a largely cross-sectional cohort of 401 subjects with type 1 diabetes (median duration 4.5 years [range 0-60]). Indeed, a combined model with incorporation of disease duration, age at onset, GRS, and titers of IA-2A, ZnT8A, and GADA provided superior capacity to predict C-peptide detection (quasi-likelihood information criterion [QIC] = 334.6) compared with the capacity of disease duration, age at onset, and GRS as the sole parameters (QIC = 359.2). These findings support the need for longitudinal validation of our combinatorial model. The ability to project the rate and extent of decline in residual C-peptide production for individuals with type 1 diabetes could critically inform enrollment and benchmarking for clinical trials where investigators are seeking to preserve or restore endogenous β-cell function. Topics: Autoantibodies; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Humans; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Zinc Transporter 8 | 2021 |
A comparison of glycemic parameters and their relationship with C-peptide and Proinsulin levels during partial remission and non-remission periods in children with type 1 diabetes mellitus - a cross-sectional study.
Currently, there is a lack of data relating to glycemic parameters and their relationship with C-peptide (CP) and proinsulin (PI) during the partial remission period (PRP) in type 1 diabetes mellitus (T1D). The aim of this study was to evaluate glycemic parameters in children with T1D who are in the PRP using intermittently scanned continuous glucose monitoring systems (isCGMS) and to investigate any relationships between CP and PI levels.. The study included 21 children who were in the PRP and 31 children who were not. A cross-sectional, non-randomized study was performed. Demographic, clinical data were collected and 2 week- isCGMS data were retrieved.. The Serum CP showed a positive correlation with time-in-range in the PRP (p:0.03), however PI showed no correlations with glycemic parameters in both periods. The Serum CP and PI levels and the PI:CP ratio were significantly higher in the PRP group than in the non-PRP group. In the non-PRP group, the PI level was below 0.1 pmol/L (which is the detectable limit) in only 2 of the 17 cases as compared with none in the PRP group. Similarly, only 2 of the 17 children in the non-PRP group had CP levels of less than 0.2 nmol / L, although both had detectable PI levels. Overall time-in-range (3. 9-1.0 mmol/L) was significantly high in the PRP group. In contrast, the mean sensor glucose levels, time spent in hyperglycemia, and coefficient of variation levels (32.2vs 40.5%) were significantly lower in the PRP group.. Although the mean glucose and time in range during the PRP was better than that in the non-PRP group, the glycemic variability during this period was not as low as expected. While the CP levels showed an association with TIR during the PRP, there was no correlation between PI levels and glycemic parameters. Further studies are needed to determine if PI might prove to be a useful parameter in clinical follow-up. Topics: Adolescent; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Male; Proinsulin; Remission, Spontaneous | 2021 |
Index60 as an additional diagnostic criterion for type 1 diabetes.
We aimed to compare characteristics of individuals identified in the peri-diagnostic range by Index60 (composite glucose and C-peptide measure) ≥2.00, 2 h OGTT glucose ≥11.1 mmol/l, or both.. We studied autoantibody-positive participants in the Type 1 Diabetes TrialNet Pathway to Prevention study who, at their baseline OGTT, had 2 h blood glucose ≥11.1 mmol/l and/or Index60 ≥2.00 (n = 354, median age = 11.2 years, age range = 1.7-46.6; 49% male, 83% non-Hispanic White). Type 1 diabetes-relevant characteristics (e.g., age, C-peptide, autoantibodies, BMI) were compared among three mutually exclusive groups: 2 h glucose ≥11.1 mmol/l and Index60 <2.00 [Glu(+), n = 76], 2 h glucose <11.1 mmol/l and Index60 ≥2.00 [Ind(+), n = 113], or both 2 h glucose ≥11.1 mmol/l and Index60 ≥2.00 [Glu(+)/Ind(+), n = 165].. Participants in Glu(+), vs those in Ind(+) or Glu(+)/Ind(+), were older (mean ages = 22.9, 11.8 and 14.7 years, respectively), had higher early (30-0 min) C-peptide response (1.0, 0.50 and 0.43 nmol/l), higher AUC C-peptide (2.33, 1.13 and 1.10 nmol/l), higher percentage of overweight/obesity (58%, 16% and 30%) (all comparisons, p < 0.0001), and a lower percentage of multiple autoantibody positivity (72%, 92% and 93%) (p < 0.001). OGTT-stimulated C-peptide and glucose patterns of Glu(+) differed appreciably from Ind(+) and Glu(+)/Ind(+). Progression to diabetes occurred in 61% (46/76) of Glu(+) and 63% (71/113) of Ind(+). Even though Index60 ≥2.00 was not a Pathway to Prevention diagnostic criterion, Ind(+) had a 4 year cumulative diabetes incidence of 95% (95% CI 86%, 98%).. Participants in the Ind(+) group had more typical characteristics of type 1 diabetes than participants in the Glu(+) did and were as likely to be diagnosed. However, unlike Glu(+) participants, Ind(+) participants were not identified at the baseline OGTT. Topics: Adolescent; Adult; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Decision Support Techniques; Diabetes Mellitus, Type 1; Disease Progression; Early Diagnosis; Female; Glucose Tolerance Test; Humans; Infant; Islets of Langerhans; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies; Young Adult | 2021 |
New and Unique Clusters of Type 2 Diabetes Identified in Indians.
Type 2 diabetes (T2D), the most common form of diabetes, is recognized as being a heterogenous disorder, and presents a universal threat to health. In T2D, the pathophysiology and phenotype differ significantly by ethnicity, particularly among Asian Indians, who are known to have the 'Asian Indian phenotype', which makes them more susceptible to develop T2D than white Caucasians. The recent subclassification of T2D into different subtypes or clusters, which behave differently with respect to clinical presentation and risk of developing complications is a remarkable development. Five unique "clusters" of individuals with diabetes were described in the Scandinavian population [Severe Autoimmune Diabetes (SAID), Severe Insulin Deficient Diabetes (SIDD), Severe Insulin Resistant Diabetes (SIRD), Mild Obesity-related Diabetes (MOD) and Mild Age-Related Diabetes (MARD)]. For the first time in India, identification of clusters of diabetes was done on 19,084 individuals with T2D, using 8 clinically relevant variables (age at diagnosis, BMI, waist circumference, HbA1c, triglycerides, HDL cholesterol and fasting and stimulated C-peptide). Four replicable clusters were identified [SIDD, MARD, IROD (Insulin Resistant Obese Diabetes) and CIRDD (Combined Insulin Resistant and Deficient Diabetes)], two of which were unique to the Indian population (IROD and CIRDD). Clustering of T2D helps i) to accurately subclassify diabetes into different subtypes, ii) plan therapies based on the pathophysiology, iii) predict prognosis and prevent diabetic complications and iv) helps in our approach to precision diabetes. Further studies would help us to refine the usefulness of these clusters of T2D particularly in the Indian population, with respect to selection of appropriate therapies and hopefully in the prevention of complications of diabetes. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; India; Insulin Resistance | 2021 |
A little help from residual β cells has long-lasting clinical benefits.
Following type 1 diabetes (T1D) diagnosis, declining C-peptide levels reflect deteriorating β cell function. However, the precise C-peptide levels that indicate protection from severe hypoglycemia remain unknown. In this issue of the JCI, Gubitosi-Klug et al. studied participants from the landmark and ongoing Diabetes Control and Complications Trial (DCCT) and the Epidemiology of Diabetes Interventions and Complications (EDIC) study that had long-standing (about 35 years) T1D. The authors correlated severe hypoglycemia and other disease outcomes with residual C-peptide levels. While C-peptide secretion failed to associate with hemoglobin A1c (HbA1c) or microvascular complications, C-peptide levels greater than 0.03 nmol/L were linked with fewer episodes of severe hypoglycemia. These findings suggest that efforts to preserve finite β cell function early in T1D can have meaningful, long-standing health benefits for patients. Topics: C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Hypoglycemia | 2021 |
Glucagon blockade restores functional β-cell mass in type 1 diabetic mice and enhances function of human islets.
We evaluated the potential for a monoclonal antibody antagonist of the glucagon receptor (Ab-4) to maintain glucose homeostasis in type 1 diabetic rodents. We noted durable and sustained improvements in glycemia which persist long after treatment withdrawal. Ab-4 promoted β-cell survival and enhanced the recovery of insulin Topics: Animals; Antibodies, Monoclonal; Blood Glucose; C-Peptide; Cell Lineage; Cell Transdifferentiation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Gene Expression; Glucagon; Glucagon-Secreting Cells; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Mice, Inbred NOD; Organ Size; Receptors, Glucagon; Treatment Outcome | 2021 |
Clinical features, biochemistry, and HLA-DRB1 status in youth-onset type 1 diabetes in Sudan.
To further understand clinical and biochemical features, and HLA-DRB1 genotypes, in new cases of diabetes in Sudanese children and adolescents.. Demographic characteristics, clinical information, and biochemical parameters (blood glucose, HbA1c, C-peptide, autoantibodies against glutamic acid decarboxylase 65 [GADA] and insulinoma-associated protein-2 [IA-2A], and HLA-DRB1) were assessed in 99 individuals <18 years, recently (<18 months) clinically diagnosed with T1D. HLA-DRB1 genotypes for 56 of these Arab individuals with T1D were compared to a mixed control group of 198 healthy Arab (75%) and African (25%) individuals without T1D.. Mean ± SD age at diagnosis was 10.1 ± 4.3 years (range 0.7-17.6 years) with mode at 9-12 years. A female preponderance was observed. Fifty-two individuals (55.3%) presented in diabetic ketoacidosis (DKA). Mean ± SD serum fasting C-peptide values were 0.22 ± 0.25 nmol/L (0.66±0.74 ng/ml). 31.3% were autoantibody negative, 53.4% were GADA positive, 27.2% were IA-2A positive, with 12.1% positive for both autoantibodies. Association analysis compared to 198 controls of similar ethnic origin revealed strong locus association with HLA-DRB1 (p < 2.4 × 10. Young Sudanese individuals with T1D generally have similar characteristics to reported European-origin T1D populations. However, they have higher rates of DKA and slightly lower autoantibody rates than reported European-origin populations, and a particularly strong association with HLA-DRB1*03:01. Topics: Adolescent; Age of Onset; Autoantibodies; Biomarkers; C-Peptide; Case-Control Studies; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Genetic Predisposition to Disease; Genotype; Glutamate Decarboxylase; HLA-DRB1 Chains; Humans; Infant; Male; Sudan | 2021 |
Three-phasic pattern of C-peptide decline in type 1 diabetes patients with partial remission.
To explore the different patterns of C-peptide decline in patients with and without partial remission of newly diagnosed type 1 diabetes (T1D).. A total of 298 patients with new-onset T1D were followed up regularly at 3 months' interval to investigate the loss of C-peptide. Partial remission was determined by postprandial C-peptide ≥300 pmol/L or insulin dose-adjusted A1c ≤ 9 in the absence of C-peptide. Beta-cell function was defined as preserved, residual or failed by postprandial C-peptide of ≥200 pmol/L, 50-200 pmol/L or ≤50 pmol/L, respectively.. Altogether, 199 out of 298 patients (125 adults) had partial remission. The pattern of C-peptide change in patients with partial remission was three-phasic, demonstrating an upward trend followed by a downward trend of fast first and then slow, while the pattern in patients without partial remission was biphasic, showing an initial fast fall and a subsequent slower decrease. The patterns remained consistent when patients were stratified by the age of onset. At 3 years, there were 71% of the patients with partial remission still had preserved or residual beta-cell function, while 89% of the patients who had no partial remission developed beta-cell function failure. In patients whose partial remission ended, the average C-peptide was still higher than duration-matched patients without partial remission.. Patients with partial remission of T1D have a distinct three-phasic pattern of C-peptide decline, other than the widely recognized biphasic pattern. The effect of partial remission still exists after remission ends. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin-Secreting Cells; Remission, Spontaneous | 2021 |
C-peptide enhances glucagon secretion in response to hyperinsulinemia under euglycemic and hypoglycemic conditions.
Several studies have associated the presence of residual insulin secretion capability (also referred to as being C-peptide positive) with lower risk of insulin-induced hypoglycemia in patients with type 1 diabetes (T1D), although the reason is unclear. We tested the hypothesis that C-peptide infusion would enhance glucagon secretion in response to hyperinsulinemia during euglycemic and hypoglycemic conditions in dogs (5 male/4 female). After a 2-hour basal period, an intravenous (IV) infusion of insulin was started, and dextrose was infused to maintain euglycemia for 2 hours. At the same time, an IV infusion of either saline (SAL) or C-peptide (CPEP) was started. After this euglycemic period, the insulin and SAL/CPEP infusions were continued for another 2 hours, but the glucose was allowed to fall to approximately 50 mg/dL. In response to euglycemic-hyperinsulinemia, glucagon secretion decreased in SAL but remained unchanged from the basal period in CPEP condition. During hypoglycemia, glucagon secretion in CPEP was 2 times higher than SAL, and this increased net hepatic glucose output and reduced the amount of exogenous glucose required to maintain glycemia. These data suggest that the presence of C-peptide during IV insulin infusion can preserve glucagon secretion during euglycemia and enhance it during hypoglycemia, which could explain why T1D patients with residual insulin secretion are less susceptible to hypoglycemia. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dogs; Female; Glucagon; Hyperinsulinism; Hypoglycemia; Hypoglycemic Agents; Male | 2021 |
Low rate of latent autoimmune diabetes in adults (LADA) in patients followed for type 2 diabetes: A single center's experience in Turkey.
In this study, we aimed to determine the frequency of and the clinical and metabolic features of patients with latent autoimmune diabetes in adults (LADA) at a single center in Turkey.. Patients over 30 years of age diagnosed with type 2 diabetes who did not require insulin for a minimum of 6 months following diagnosis were included. Data from 324 patients (163 women; 161 men), with a mean age of 54.97 ± 7.53 years, were analyzed in the study. Levels of antibodies to glutamate decarboxylase (anti-GAD) were measured in all patients, and LADA was diagnosed in patients testing positive for anti-GAD antibodies.. We observed a LADA frequency of 1.5% among Turkish patients followed for type 2 diabetes. The presence of obesity and metabolic syndrome did not exclude LADA, and patients with LADA had worse glycemic control than patients with type 2 diabetes did. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Infant; Latent Autoimmune Diabetes in Adults; Male; Middle Aged; Turkey | 2021 |
Insulin micro-secretion in Type 1 diabetes and related microRNA profiles.
The aim of this cross-sectional study was to compare plasma C-peptide presence and levels in people without diabetes (CON) and with Type 1 diabetes and relate C-peptide status to clinical factors. In a subset we evaluated 50 microRNAs (miRs) previously implicated in beta-cell death and associations with clinical status and C-peptide levels. Diabetes age of onset was stratified as adult (≥ 18 y.o) or childhood (< 18 y.o.), and diabetes duration was stratified as ≤ 10 years, 10-20 years and > 20 years. Plasma C-peptide was measured by ultrasensitive ELISA. Plasma miRs were quantified using TaqMan probe-primer mix on an OpenArray platform. C-peptide was detectable in 55.3% of (n = 349) people with diabetes, including 64.1% of adults and 34.0% of youth with diabetes, p < 0.0001 and in all (n = 253) participants without diabetes (CON). C-peptide levels, when detectable, were lower in the individuals with diabetes than in the CON group [median lower quartile (LQ)-upper quartile (UQ)] 5.0 (2.6-28.7) versus 650.9 (401.2-732.4) pmol/L respectively, p < 0.0001 and lower in childhood versus adult-onset diabetes [median (LQ-UQ) 4.2 (2.6-12.2) pmol/L vs. 8.0 (2.3-80.5) pmol/L, p = 0.02, respectively]. In the childhood-onset group more people with longer diabetes duration (> 20 years) had detectable C-peptide (60%) than in those with shorter diabetes duration (39%, p for trend < 0.05). Nine miRs significantly correlated with detectable C-peptide levels in people with diabetes and 16 miRs correlated with C-peptide levels in CON. Our cross-sectional study results are supportive of (a) greater beta-cell function loss in younger onset Type 1 diabetes; (b) persistent insulin secretion in adult-onset diabetes and possibly regenerative secretion in childhood-onset long diabetes duration; and (c) relationships of C-peptide levels with circulating miRs. Confirmatory clinical studies and related basic science studies are merited. Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Autoantibodies; Autoimmunity; Biomarkers; Blood Glucose; C-Peptide; Child; Circulating MicroRNA; Diabetes Mellitus, Type 1; Female; Gene Expression Regulation; Glycated Hemoglobin; Humans; Insulin Secretion; Insulin-Secreting Cells; Male; MicroRNAs; Middle Aged; Young Adult | 2021 |
Characterization of Human CD4 T Cells Specific for a C-Peptide/C-Peptide Hybrid Insulin Peptide.
Hybrid Insulin Peptides (HIPs), which consist of insulin fragments fused to other peptides from β-cell secretory granule proteins, are CD4 T cell autoantigens in type 1 diabetes (T1D). We have studied HIPs and HIP-reactive CD4 T cells extensively in the context of the non-obese diabetic (NOD) mouse model of autoimmune diabetes and have shown that CD4 T cells specific for HIPs are major contributors to disease pathogenesis. Additionally, in the human context, HIP-reactive CD4 T cells can be found in the islets and peripheral blood of T1D patients. Here, we performed an in-depth characterization of the CD4 T cell response to a C-peptide/C-peptide HIP (HIP11) in human T1D. We identified the TCR expressed by the previously-reported HIP11-reactive CD4 T cell clone E2, which was isolated from the peripheral blood of a T1D patient, and determined that it recognizes HIP11 in the context of HLA-DQ2. We also identified a HIP11-specific TCR directly in the islets of a T1D donor and demonstrated that this TCR recognizes a different minimal epitope of HIP11 presented by HLA-DQ8. We generated and tested an HLA-DQ2 tetramer loaded with HIP11 that will enable direct Topics: Autoantigens; C-Peptide; CD4-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Epitopes; Female; HLA-DQ Antigens; Humans; Insulin; Islets of Langerhans; K562 Cells; Male; Receptors, Antigen, T-Cell | 2021 |
Residual
To investigate the natural history and related factors of the pancreatic Topics: Adolescent; Adult; Age of Onset; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease Progression; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin Secretion; Insulin-Secreting Cells; Male; Proportional Hazards Models; Time Factors; Young Adult | 2021 |
Simplifying prediction of disease progression in pre-symptomatic type 1 diabetes using a single blood sample.
Accurate prediction of disease progression in individuals with pre-symptomatic type 1 diabetes has potential to prevent ketoacidosis and accelerate development of disease-modifying therapies. Current tools for predicting risk require multiple blood samples taken during an OGTT. Our aim was to develop and validate a simpler tool based on a single blood draw.. Models to predict disease progression using a single OGTT time point (0, 30, 60, 90 or 120 min) were developed using TrialNet data collected from relatives with type 1 diabetes and validated in independent populations at high genetic risk of type 1 diabetes (TrialNet, Diabetes Prevention Trial-Type 1, The Environmental Determinants of Diabetes in the Young [1]) and in a general population of Bavarian children who participated in Fr1da.. Cox proportional hazards models combining plasma glucose, C-peptide, sex, age, BMI, HbA. Prediction models based on a single OGTT blood draw accurately predict disease progression from stage 1 or 2 to stage 3 type 1 diabetes. The operational simplicity of M Topics: Adolescent; Area Under Curve; Asymptomatic Diseases; Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin Antibodies; Male; Proportional Hazards Models; Receptor-Like Protein Tyrosine Phosphatases, Class 8; ROC Curve; Zinc Transporter 8 | 2021 |
Changes in innate and adaptive immunity over the first year after the onset of type 1 diabetes.
The development of the immune phenotype in patients with type 1 diabetes (T1D) during the first year following disease onset remains poorly described, and studies analysing the longitudinal development of a complex set of immunological and metabolic parameters are missing. Thus, we aim to provide such complex view in a cohort of 38 children with new onset T1D who were prospectively followed for 1 year.. All subjects were tested for a set of immunological parameters (complete blood count; serum immunoglobulins; and T, B and dendritic cells), HbA1c and daily insulin dose at baseline and at 6 and 12 months after T1D diagnosis. A mixed meal tolerance test was administered to each of the subjects 12 months after diagnosis, and the C-peptide area under the curve (AUC) was noted and was then tested for association with all immunological parameters.. A gradual decrease in leukocytes (adjusted p = 0.0012) was reflected in a significant decrease in neutrophils (adjusted p = 0.0061) over the post-onset period, whereas Tregs (adjusted p = 0.0205) and originally low pDCs (adjusted p < 0.0001) increased. The expression of the receptor for BAFF (BAFFR) on B lymphocytes (adjusted p = 0.0127) markedly increased after onset. No immunological parameters were associated with C-peptide AUC; however, we observed a linear increase in C-peptide AUC with the age of the patients (p < 0.0001).. Our study documents substantial changes in the innate and adaptive immune system over the first year after disease diagnosis but shows no association between immunological parameters and residual beta-cell activity. The age of patients remains the best predictor of C-peptide AUC, whereas the role of the immune system remains unresolved. Topics: Adaptive Immunity; Adolescent; Age of Onset; B-Lymphocytes; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Immunity, Innate; Insulin; Insulin-Secreting Cells; Leukocyte Count; Male; Prospective Studies; T-Lymphocytes, Regulatory | 2020 |
Nivolumab-induced fulminant type 1 diabetes with precipitous fall in C-peptide level.
We describe here a case of nivolumab-induced type 1 diabetes, which developed within 9 days of treatment. The case highlights the importance of frequent monitoring of glucose after initiation of nivolumab treatment. Topics: Aged; Antineoplastic Agents, Immunological; C-Peptide; Carcinoma, Non-Small-Cell Lung; Diabetes Mellitus, Type 1; Humans; Immune Checkpoint Inhibitors; Lung Neoplasms; Male; Nivolumab | 2020 |
BETA-2 score is an early predictor of graft decline and loss of insulin independence after pancreatic islet allotransplantation.
This study aimed to evaluate whether the BETA-2 score is a reliable early predictor of graft decline and loss of insulin independence after islet allotransplantation. Islet transplant procedures were stratified into 3 groups according to clinical outcome: long-term insulin independence without islet graft decline (group 1, N = 9), initial insulin independence with subsequent islet graft decline and loss of insulin independence (group 2, N = 13), and no insulin independence (group 3, N = 13). BETA-2 was calculated on day 75 and multiple times afterwards for up to 145 months posttransplantation. A BETA-2 score cut-off of 17.4 on day 75 posttransplantation was discerned between group 1 and groups 2 and 3 (area under the receiver operating characteristic 0.769, P = .005) with a sensitivity and negative predictive value of 100%. Additionally, BETA-2 ≥ 17.4 at any timepoint during follow-up reflected islet function required for long-term insulin independence. While BETA-2 did not decline below 17.4 for each of the 9 cases from group 1, the score decreased below 17.4 for all transplants from group 2 with subsequent loss of insulin independence. The reduction of BETA-2 below 17.4 predicted 9 (1.5-21) months in advance subsequent islet graft decline and loss of insulin independence (P = .03). This finding has important implications for posttransplant monitoring and patient care. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation | 2020 |
Anti-inflammatory effects of C-peptide on kidney of type 1 diabetes mellitus animal model.
Type 1 diabetes mellitus (T1DM) is characterized by C-peptide deficiency and elevated levels of pro-inflammatory cytokines. The aim of this study was to investigate the role of C-peptide in renal and inflammatory complications in streptozotocin (STZ)-diabetic mice model of T1DM with kidney disease. The study was performed in 8-week old male C57BL/6 mice. Two streptozotocin-diabetic groups (a T1DM animal model), after 4 weeks of diabetes, were treated with subcutaneous infusion of either vehicle (n = 12) or C-peptide (n = 11). Two non-diabetic groups (vehicle, n = 10; C-peptide, n = 9) were treated using the same protocol as described for the diabetic mice. The treatment with C-peptide in the diabetic group reduced the urinary levels of IL17 and TNFα, as well as IL4 and IL10 (p < 0.05). Contrary, the diabetic + C-peptide group presented higher IL10 gene expression in kidney. Besides, it displayed a reduction of TNFα gene expression. The data suggest that C-peptide may modulate pro- and anti-inflammatory signalling pathways, resulting in attenuation of kidney inflammation in T1DM animal model. Topics: Animals; Anti-Inflammatory Agents; C-Peptide; Cytokines; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Inflammation; Kidney; Kidney Diseases; Male; Mice; Mice, Inbred C57BL | 2020 |
Glutamic Acid Decarboxylase Autoantibody Detection by Electrochemiluminescence Assay Identifies Latent Autoimmune Diabetes in Adults with Poor Islet Function.
The detection of glutamic acid decarboxylase 65 (GAD65) autoantibodies is essential for the prediction and diagnosis of latent autoimmune diabetes in adults (LADA). The aim of the current study was to compare a newly developed electrochemiluminescence (ECL)-GAD65 antibody assay with the established radiobinding assay, and to explore whether the new assay could be used to define LADA more precisely.. Serum samples were harvested from 141 patients with LADA, 95 with type 1 diabetes mellitus, and 99 with type 2 diabetes mellitus, and tested for GAD65 autoantibodies using both the radiobinding assay and ECL assay. A glutamic acid decarboxylase antibodies (GADA) competition assay was also performed to assess antibody affinity. Furthermore, the clinical features of these patients were compared.. Eighty-eight out of 141 serum samples (62.4%) from LADA patients were GAD65 antibody-positive by ECL assay. Compared with ECL-GAD65 antibody-negative patients, ECL-GAD65 antibody-positive patients were leaner (. Patients with ECL-GAD65 antibody-negative share a similar phenotype with type 2 diabetes mellitus patients, whereas patients with ECL-GAD65 antibody-positive resemble those with type 1 diabetes mellitus. Thus, the detection of GADA using ECL may help to identify the subtype of LADA. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Islets of Langerhans; Latent Autoimmune Diabetes in Adults; Male; Middle Aged; Phenotype; Young Adult | 2020 |
A Hybrid Insulin Epitope Maintains High 2D Affinity for Diabetogenic T Cells in the Periphery.
β-Cell antigen recognition by autoreactive T cells is essential in type 1 diabetes (T1D) pathogenesis. Recently, insulin hybrid peptides (HIPs) were identified as strong agonists for CD4 diabetogenic T cells. Here, using BDC2.5 transgenic and NOD mice, we investigated T-cell recognition of the HIP2.5 epitope, which is a fusion of insulin C-peptide and chromogranin A (ChgA) fragments, and compared it with the WE14 and ChgA Topics: Animals; Antibody Affinity; C-Peptide; CD4-Positive T-Lymphocytes; Chromogranin A; Diabetes Mellitus, Type 1; Epitopes, T-Lymphocyte; Islets of Langerhans; Lymph Nodes; Mice; Mice, Inbred NOD; Mice, Transgenic; Peptide Fragments; Receptors, Antigen, T-Cell; Spleen; T-Lymphocytes; Thymocytes; Thymus Gland | 2020 |
The associations between three genome-wide risk variants for serum C-peptide of T1D and autoantibody-positive T1D risk, and clinical characteristics in Chinese population.
Recent meta-genome-wide association studies identified several genetic variants associated with beta-cell function in type 1 diabetes (T1D). The aim of this study was to investigate the associations between these variants and T1D risk, C-peptide levels, islet-specific autoantibodies, and lipid levels in Chinese Han population.. A total of 1005 unrelated autoantibody-positive T1D cases and 1417 healthy controls were included, which were genotyped for rs559047, rs9260151, and rs3135002. T1D individuals were measured for both C-peptide and lipid levels. Logistic regression models were used to examine these associations.. We found that rs3135002 A allele showed a genome-wide significant association with T1D risk (OR = 0.22, 95% CI = 0.17-0.30; P = 7.49 × 10. Our results indicate that there are both similarities and differences for the associations of genetic variants among T1D development, progression, and related autoimmunity, metabolic traits. Topics: Adolescent; Adult; Alleles; Autoantibodies; C-Peptide; Child; Child, Preschool; China; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genetic Predisposition to Disease; Genome-Wide Association Study; Genotype; Humans; Infant; Lipoproteins, HDL; Male; Middle Aged; Polymorphism, Single Nucleotide; Young Adult | 2020 |
Bone turnover markers during the remission phase in children and adolescents with type 1 diabetes.
In rodents, osteocalcin (OCN) stimulates insulin production and insulin sensitivity, both important factors during partial remission in humans with type 1 diabetes (T1D). However, decreased OCN has been reported in both adult and pediatric T1D. This study aims at investigating bone turnover and partial remission in children and adolescents with recent onset T1D.. Ninety-nine individuals (33% girls) were recruited within 3 months of T1D onset and examined three times, 6 months apart. Outcome variables were bone formation markers OCN and procollagen type 1 amino-terminal propeptide (P1NP) and the bone resorption marker C-terminal crosslinked telopeptide of type 1 collagen (CTX). Dependent variables included IDAA1c (surrogate marker of partial remission), total body bone mineral density (BMD) and stimulated C-peptide as representative of endogenous insulin production.. OCN- and P1NP Z-scores were significantly decreased throughout the study, whereas CTX Z-scores were increased. None of the bone turnover markers changed significantly between visits. Total body BMD Z-score did not change during the study but was significantly higher than the reference population at visit 2 (P = .035). There were no differences in the bone turnover markers for those in partial remission as defined by either C-peptide or IDAA1c at any visit. The individual change in CTX Z-score was negatively associated with the increase of IDAA1c (P = .030) independent of C-peptide decline (P = .034).. Bone turnover markers indicate increased bone resorption and decreased bone formation during the first year of T1D. The negative association between bone resorption and IDAA1c might represent compensatory mechanisms affecting insulin sensitivity. Topics: Adolescent; Biomarkers; Bone Density; Bone Remodeling; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Osteocalcin; Peptide Fragments; Procollagen; Remission Induction | 2020 |
Serum chromogranin A level continuously rises with the progression of type 1 diabetes, and indicates the presence of both enterochromaffin-like cell hyperplasia and autoimmune gastritis.
The relationship of chromogranin A (CgA) levels above the normal range with various outcomes, such as glycated hemoglobin levels, enterochromaffin-like cell hyperplasia and autoimmune gastritis, was investigated in type 1 diabetes patients with special regard to the progression of comorbidities.. A cohort study on 153 type 1 diabetes patients was carried out with a prospective branch on clinical and laboratory data, and a retrospective branch on histological data obtained by gastroscopy.. Patients with CgA levels above the upper limit of the normal range (n = 28) had significantly higher glycated hemoglobin levels (P = 0.0160) than those with CgA in the normal range (n = 125). The correlation between CgA and glycated hemoglobin was significant (P < 0.0001), but weak (R = +0.32). A slight, but steady elevation (P = 0.0410) in CgA level was observed to co-vary with the duration of type 1 diabetes. Enterochromaffin-like cell hyperplasia and autoimmune gastritis was significantly more frequent (P = 0.0087 for both) in the high CgA group. Detailed analyses on gastric tissue samples confirmed a progression of enterochromaffin-like cell hyperplasia (P = 0.0192) accompanied by CgA elevation (P = 0.0316).. The early detection and follow up of the later progression of enterochromaffin-like cell hyperplasia and autoimmune gastritis into gastric neuroendocrine tumors, which have ~100-fold greater incidence in type 1 diabetes patients, can be achieved by assessment of CgA levels. Therefore, the use of CgA could be considered as a novel auxiliary biomarker in the care of these type 1 diabetes complications. Topics: Adult; Autoantibodies; Autoimmune Diseases; C-Peptide; Chromogranin A; Diabetes Mellitus, Type 1; Disease Progression; Enterochromaffin-like Cells; Female; Gastritis; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hungary; Hyperplasia; Islets of Langerhans; Male; Prospective Studies | 2020 |
High residual C-peptide likely contributes to glycemic control in type 1 diabetes.
BACKGROUNDResidual C-peptide is detected in many people for years following the diagnosis of type 1 diabetes; however, the physiologic significance of low levels of detectable C-peptide is not known.METHODSWe studied 63 adults with type 1 diabetes classified by peak mixed-meal tolerance test (MMTT) C-peptide as negative (<0.007 pmol/mL; n = 15), low (0.017-0.200; n = 16), intermediate (>0.200-0.400; n = 15), or high (>0.400; n = 17). We compared the groups' glycemia from continuous glucose monitoring (CGM), β cell secretory responses from a glucose-potentiated arginine (GPA) test, insulin sensitivity from a hyperinsulinemic-euglycemic (EU) clamp, and glucose counterregulatory responses from a subsequent hypoglycemic (HYPO) clamp.RESULTSLow and intermediate MMTT C-peptide groups did not exhibit β cell secretory responses to hyperglycemia, whereas the high C-peptide group showed increases in both C-peptide and proinsulin (P ≤ 0.01). All groups with detectable MMTT C-peptide demonstrated acute C-peptide and proinsulin responses to arginine that were positively correlated with peak MMTT C-peptide (P < 0.0001 for both analytes). During the EU-HYPO clamp, C-peptide levels were proportionately suppressed in the low, intermediate, and high C-peptide compared with the negative group (P ≤ 0.0001), whereas glucagon increased from EU to HYPO only in the high C-peptide group compared with negative (P = 0.01). CGM demonstrated lower mean glucose and more time in range for the high C-peptide group.CONCLUSIONThese results indicate that in adults with type 1 diabetes, β cell responsiveness to hyperglycemia and α cell responsiveness to hypoglycemia are observed only at high levels of residual C-peptide that likely contribute to glycemic control.FUNDINGFunding for this work was provided by the Leona M. and Harry B. Helmsley Charitable Trust, the National Center for Advancing Translational Sciences, and the National Institute of Diabetes and Digestive and Kidney Diseases. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon-Secreting Cells; Humans; Hyperglycemia; Insulin-Secreting Cells; Male; Middle Aged | 2020 |
Complicated curve association of body weight at diagnosis with C-peptide in children and adults with new-onset type 1 diabetes.
To investigate the association of body mass index (BMI) or BMI z-score (BMIz) at diagnosis with β-cell function in new-onset type 1 diabetes (T1D) patients in children and adults.. This was a retrospective cohort study; 256 children (<18 years) and 245 adults (≥18 years) with less than 1-year duration were recruited and followed for 4 years with an interval of 12 months. Smooth curve fitting, a two-piecewise linear model, and Cox proportional hazards models were utilized to investigate the influence of BMI/BMIz on C-peptide levels.. Association between BMI/BMIz and C-peptide in T1D followed a complicated J curve pattern, and heavier patients had greater C-peptide at diagnosis and a lower risk of β-cell failure at 4 years, suggesting that baseline BMI is a useful predictor for β-cell function in patients with T1D. Topics: Adolescent; Adult; Age of Onset; Biomarkers; Blood Glucose; Body Mass Index; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Male; Prognosis; Retrospective Studies | 2020 |
Clinical trial data validate the C-peptide estimate model in type 1 diabetes.
Topics: Adolescent; Adult; Antilymphocyte Serum; Area Under Curve; Biomarkers, Pharmacological; Blood Glucose; C-Peptide; Child; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diagnostic Techniques, Endocrine; Female; Glycated Hemoglobin; Granulocyte Colony-Stimulating Factor; Humans; Male; Meals; Outcome Assessment, Health Care; Prognosis; Treatment Outcome; Young Adult | 2020 |
Early and late C-peptide responses during oral glucose tolerance testing are oppositely predictive of type 1 diabetes in autoantibody-positive individuals.
We examined whether the timing of the C-peptide response during an oral glucose tolerance test (OGTT) in relatives of patients with type 1 diabetes (T1D) is predictive of disease onset. We examined baseline 2-h OGTTs from 670 relatives participating in the Diabetes Prevention Trial-Type 1 (age: 13.8 ± 9.6 years; body mass index z-score: 0.3 ± 1.1; 56% male) using univariate regression models. T1D risk increased with lower early C-peptide responses (30-0 min) (χ Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; ROC Curve; Young Adult | 2020 |
Older age of childhood type 1 diabetes onset is associated with islet autoantibody positivity >30 years later: the Pittsburgh Epidemiology of Diabetes Complications Study.
To examine the association between islet autoantibody positivity and clinical characteristics, residual β-cell function (C-peptide) and prevalence of complications in a childhood-onset (age <17 years), long-duration (≥32 years) type 1 diabetes cohort.. Islet autoantibodies (glutamic acid decarboxylase, insulinoma-associated protein 2 and zinc transporter-8 antibodies) were measured in the serum of participants who attended the 2011-2013 Pittsburgh Epidemiology of Diabetes Complications study follow-up examination (n=177, mean age 51 years, diabetes duration 43 years).. Prevalences of islet autoantibodies were: glutamic acid decarboxylase, 32%; insulinoma-associated protein 2, 22%; and zinc transporter-8, 4%. Positivity for each islet autoantibody was associated with older age at diabetes onset (glutamic acid decarboxylase antibodies, P=0.03; insulinoma-associated protein 2 antibodies, P=0.001; zinc transporter-8 antibodies, P<0.0001). Older age at onset was also associated with an increasing number of autoantibodies (P = 0.001). Glutamic acid decarboxylase antibody positivity was also associated with lower HbA. The strong association between islet autoantibody positivity and older age at type 1 diabetes onset supports the hypothesis of a less aggressive, and thus more persistent, immune process in those with older age at onset. This observation suggests that there may be long-term persistence of heterogeneity in the underlying autoimmune process. Topics: Adult; Age of Onset; Aged; Autoantibodies; C-Peptide; Cholesterol; Cholesterol, LDL; Diabetes Complications; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Zinc Transporter 8 | 2020 |
Preserved C-peptide secretion is associated with fewer low-glucose events and lower glucose variability on flash glucose monitoring in adults with type 1 diabetes.
We aimed to assess whether persistence of C-peptide secretion is associated with less glucose variability and fewer low-glucose events in adults with type 1 diabetes who use flash monitoring.. We performed a cross-sectional study of 290 adults attending a university teaching hospital diabetes clinic, with type 1 diabetes, who use flash monitoring and in whom a random plasma C-peptide was available in the past 2 years. Variables relating to flash monitoring were compared between individuals with low C-peptide (<10 pmol/l) and those with persistent C-peptide (either 10-200 pmol/l or 10-50 pmol/l). In addition, the relationship between self-reported hypoglycaemia and C-peptide was assessed (n = 167). Data are median (interquartile range).. Preserved C-peptide secretion is associated with fewer low-glucose events and lower glucose variability on flash monitoring. This suggests that individuals with preserved C-peptide may more safely achieve intensive glycaemic targets. Topics: Adolescent; Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Logistic Models; Male; Young Adult | 2020 |
Better HbA1c during the first years after diagnosis of type 1 diabetes is associated with residual C peptide 10 years later.
To identify the factors associated with residual C peptide production at least 10 years after diagnosis in children and adolescents with type 1 diabetes.. 73 children and adolescents (<25 years), born in 1988-2005, diagnosed with type 1 diabetes were included during the 4-year study period (2013-2016). At least 10 years after diagnosis, we measured any remaining C peptide concentration using an ultrasensitive C peptide ELISA (≥1.17 pmol/L). The average hemoglobin A1c (HbA1c) was calculated during each of the 10 years after diagnosis and further grand average was calculated for the entire study period.. C peptide was detectable in 38% of participants. The C peptide concentration was 4.3±5.3 pmol/L. At onset of type 1 diabetes, participants were on average approximately 5 years of age, and their average HbA1c was 9.4% (79 mmol/mol). During the first 3 years after diagnosis, HbA1c was lower in the group with detectable C peptide at follow-up ≥10 years later. Moreover, detectable C peptide was more common among female participants. Body mass index SD scores had not increased since the 1-year follow-up, but were higher in patients with measurable C peptide. Nine participants (12%) had been diagnosed with celiac disease and two (3%) with hypothyreosis. Eighteen (25%) participants had retinopathy.. Children and adolescents with detectable C peptide after more than 10 years of diabetes duration were predominantly female and had better HbA1c than others during the first 3 years after diagnosis. Topics: Adolescent; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Infant; Longitudinal Studies; Male; Registries; Sex Factors; Sweden; Young Adult | 2020 |
Correct Diabetes Diagnosis and Treatment Allows Sailor to Remain on Active Duty.
Diabetes is a growing epidemic worldwide and among our active duty population, posing a significant threat to maintaining military health and operational readiness. Latent autoimmune diabetes in adults (LADA) is a growing clinical phenotype of diabetes, with overlap between traditional type 1 diabetes mellitus and type 2 diabetes mellitus. In this case, a 27-year-old active duty male presented with polydipsia, polyuria, polyphagia, and recent weight loss. He was diagnosed with LADA, placed on a period of limited duty status and started on insulin. Eight months after diagnosis, he was transitioned from insulin to a glucagon-like peptide-1 receptor agonist in an effort to be returned to full duty status and worldwide deployable. Over 3 years after initial diagnosis, he has achieved partial clinical remission. He remains on active duty, serving on a medically limited platform with a single medication (a glucagon-like peptide-1 receptor agonist) and high compliance with a gluten-free, low-carbohydrate diet and regular exercise. One should consider the diagnosis of LADA and its unique management, especially in the younger active duty population. Not only is making the correct diagnosis regarding the type of diabetes critical in regard to prognosis and optimal medical management, but it can affect the ability of military members to remain on active duty. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Male; Military Personnel | 2020 |
Use of Culture to Reach Metabolically Adequate Beta-cell Dose by Combining Donor Islet Cell Isolates for Transplantation in Type 1 Diabetes Patients.
Clinical islet transplantation is generally conducted within 72 hours after isolating sufficient beta-cell mass. A preparation that does not meet the sufficient dose can be cultured until this is reached after combination with subsequent ones. This retrospective study examines whether metabolic outcome is influenced by culture duration.. Forty type 1 diabetes recipients of intraportal islet cell grafts under antithymocyte globulin induction and mycophenolate mofetil-tacrolimus maintenance immunosuppression were analyzed. One subgroup (n = 10) was transplanted with preparations cultured for ≥96 hours; in the other subgroup (n = 30) grafts contained similar beta-cell numbers but included isolates that were cultured for a shorter duration. Both subgroups were compared by numbers with plasma C-peptide ≥0.5 ng/mL, low glycemic variability associated with C-peptide ≥1.0 ng/mL, and with insulin independence.. The subgroup with all cells cultured ≥96 hours exhibited longer C-peptide ≥0.5 ng/mL (103 versus 48 mo; P = 0.006), and more patients with low glycemic variability and C-peptide ≥1.0 ng/mL, at month 12 (9/10 versus 12/30; P = 0.005) and 24 (7/10 versus 6/30; P = 0.007). In addition, 9/10 became insulin-independent versus 15/30 (P = 0.03). Grafts with all cells cultured ≥96 hours did not contain more beta cells but a higher endocrine purity (49% versus 36%; P = 0.03). In multivariate analysis, longer culture duration and older recipient age were independently associated with longer graft function.. Human islet isolates with insufficient beta-cell mass for implantation within 72 hours can be cultured for 96 hours and longer to combine multiple preparations in order to reach the desired beta-cell dose and therefore result in a better metabolic benefit. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Cell Proliferation; Cells, Cultured; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Retrospective Studies; Time Factors; Tissue Culture Techniques; Treatment Outcome | 2020 |
Donor insulin use predicts beta-cell function after islet transplantation.
Insulin is routinely used to manage hyperglycaemia in organ donors and during the peri-transplant period in islet transplant recipients. However, it is unknown whether donor insulin use (DIU) predicts beta-cell dysfunction after islet transplantation. We reviewed data from the UK Transplant Registry and the UK Islet Transplant Consortium; all first-time transplants during 2008-2016 were included. Linear regression models determined associations between DIU, median and coefficient of variation (CV) peri-transplant glucose levels and 3-month islet graft function. In 91 islet cell transplant recipients, DIU was associated with lower islet function assessed by BETA-2 scores (β [SE] -3.5 [1.5], P = .02), higher 3-month post-transplant HbA1c levels (5.4 [2.6] mmol/mol, P = .04) and lower fasting C-peptide levels (-107.9 [46.1] pmol/l, P = .02). Glucose at 10 512 time points was recorded during the first 5 days peri-transplant: the median (IQR) daily glucose level was 7.9 (7.0-8.9) mmol/L and glucose CV was 28% (21%-35%). Neither median glucose levels nor glucose CV predicted outcomes post-transplantation. Data on DIU predicts beta-cell dysfunction 3 months after islet transplantation and could help improve donor selection and transplant outcomes. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Tissue Donors | 2020 |
C-Peptide Levels in Subjects Followed Longitudinally Before and After Type 1 Diabetes Diagnosis in TrialNet.
Insulin secretion declines rapidly after diagnosis of type 1 diabetes, followed by a slower rate of change. Previous studies have demonstrated that the C-peptide decline begins before the clinical diagnosis. Changes in insulin secretion in the same individuals studied from preclinical stages through and after clinical diagnosis have not been previously reported.. Antibody-positive relatives undergo sequential oral glucose tolerance testing (OGTT) as part of TrialNet's Pathway to Prevention study and continue both OGTT and mixed-meal tolerance testing (MMTT) as part of the Long-term Investigational Follow-up in TrialNet study if they develop type 1 diabetes. We analyzed glucose and C-peptide data obtained from 80 TrialNet subjects who had OGTT before and after clinical diagnosis. Separately, we compared C-peptide response to OGTT and MMTT in 127 participants after diagnosis.. C-peptide did not change significantly until 6 months before the clinical diagnosis of type 1 diabetes and continued to decline postdiagnosis, and the rates of decline for the first 6 months postdiagnosis were similar to the 6 months prediagnosis. There were no significant differences in MMTT and OGTT C-peptide responses in paired tests postdiagnosis.. This is the first analysis of C-peptide levels in longitudinally monitored patients with type 1 diabetes studied from before diagnosis and continuing to the postdiagnosis period. These data highlight the discordant timing between accelerated β-cell dysfunction and the current glucose thresholds for clinical diagnosis. To preserve β-cell function, disease-modifying therapy should start at or before the acute decline in C-peptide. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Diagnostic Techniques, Endocrine; Disease Progression; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin Secretion; Longitudinal Studies; Male; Meals; Middle Aged; Monitoring, Physiologic; Young Adult | 2020 |
The Effect of Ethnicity in the Rate of Beta-Cell Functional Loss in the First 3 Years After Type 1 Diabetes Diagnosis.
We set forth to compare ethnicities for metabolic and immunological characteristics at the clinical diagnosis of type 1 diabetes (T1D) and assess the effect of ethnicity on beta-cell functional loss within 3 years after clinical diagnosis.. We studied participants in TrialNet New Onset Intervention Trials (n = 624, median age = 14.4 years, 58% male, 8.7% Hispanic) and followed them prospectively for 3 years. Mixed meal tolerance tests (MMTT) were performed within 6 months following clinical diagnosis and repeated semiannually. Unless otherwise indicated, analyses were adjusted for age, sex, BMI Z-score, and diabetes duration.. At T1D clinical diagnosis, Hispanics, compared with non-Hispanic whites (NHW), had a higher frequency of diabetic ketoacidosis (DKA) (44.7% vs 25.3%, OR = 2.36, P = 0.01), lower fasting glucose (97 vs 109 mg/dL, P = 0.02) and higher fasting C-peptide (1.23 vs 0.94 ng/mL, P = 0.02) on the first MMTT, and higher frequency of ZnT8 autoantibody positivity (n = 201, 94.1% vs 64%, OR = 7.98, P = 0.05). After exclusion of participants in experimental arms of positive clinical trials, C-peptide area under the curve (AUC) trajectories during the first 3 years after clinical diagnosis were not significantly different between Hispanics and NHW after adjusting for age, sex, BMI-z score, and DKA (n = 413, P = 0.14).. Despite differences in the metabolic and immunological characteristics at clinical diagnosis of T1D between Hispanics and NHW, C-peptide trajectories did not differ significantly in the first 3 years following clinical diagnosis after adjustment for body mass index and other confounders. These findings may inform the design of observational studies and intervention trials in T1D. Topics: Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Female; Hispanic or Latino; Humans; Insulin-Secreting Cells; Male; Prospective Studies; White People | 2020 |
Total Pancreatectomy and Pancreatic Allotransplant in a Porcine Experimental Model.
The main objective of this experimental study was to evaluate the feasibility of diabetes induction by total pancreatectomy and pancreatic allotransplant after diabetes induction by total pancreatectomy. The secondary objective was to evaluate metabolic (C-peptide, glycemia) and inflammatory (lactate and platelet levels) parameters after diabetes induction by total pancreatectomy and pancreatic allotransplant after total pancreatectomy.. The study protocol was approved by the French Minister of Research (APAFiS no.18169). Insulin-dependent diabetes was induced by total pancreatectomy in one male Sus scrofa pig, and pancreatic allotransplant was performed, after total pancreatectomy, in 3 male Sus scrofa pigs. Total pancreatectomy was performed under general anesthesia,with meticulous dissection of the portal vein and the splenic vein to preserve the spleen. Concerning pancreas procurement, extensive pancreas preparation occurred during thewarm phase,before coldperfusion. Pancreatic allotransplant was performed using donor aorta (with superior mesenteric artery and celiac trunk).. Diabetes induction was successful, with negative C-peptide values at 3 hours after total pancreatectomy. Glycemic control without hypoglycemic events was obtained with the use of long-acting insulin administered once per day. No rapid-acting insulin was used. In animals that received pancreatic allotransplant, after enteral feeding was started, glycemic control without hypoglycemic events and without insulin was obtained in 2 animals.. In an experimental porcine model, diabetes induction by total pancreatectomy and pancreatic allotransplant after total pancreatectomy are feasible and effective. The development of these models offers the potential for new investigations into ischemia-reperfusion injuries, improvement of pancreas procurement methods, and preservation techniques. Topics: Animals; Biomarkers; Blood Glucose; Blood Platelets; C-Peptide; Diabetes Mellitus, Type 1; Disease Models, Animal; Feasibility Studies; Hypoglycemic Agents; Insulin Glargine; Lactic Acid; Male; Pancreas Transplantation; Pancreatectomy; Sus scrofa; Time Factors; Transplantation, Homologous | 2020 |
Decline Pattern of Beta Cell Function in LADA: Relationship to GAD Autoantibodies.
Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Prospective Studies | 2020 |
C-peptide corrects hepatocellular dysfunction in a rat model of type 1 diabetes.
C-peptide is gaining much interest recently due to its well-documented beneficial effects on multiple organ dysfunction induced by diabetes. Our study was designed to investigate the effect of C-peptide on hepatocellular dysfunction in diabetic rats. Wistar male rats were separated into four groups: control, diabetic, diabetic + insulin, and diabetic + C-peptide. Serum levels of glucose, insulin, and liver biomarkers were assessed. Liver sections were collected for histopathological examination and immuno-histochemical assessment of tumor necrosis factor alpha (TNF-α). Oxidative stress markers and gene expression of inducible nitric oxide synthase (iNOS), transforming growth factor beta 1 (TGF-β1), and glucose-6-phosphatase (G6Pase) were also measured in liver tissues. C-peptide administration prevented hepatic dysfunction induced by diabetes to a similar extent as that of insulin which was confirmed microscopically. We concluded that C-peptide could be used as an alternative therapy to insulin to correct hepatocellular dysfunction associated with type 1 diabetes mellitus (T1DM). Topics: Animals; Biomarkers; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Liver; Male; Rats; Rats, Wistar; Streptozocin | 2020 |
Curcumin Ameliorate Diabetes type 1 Complications through Decreasing Pro-inflammatory Cytokines in C57BL/6 Mice.
Type 1 diabetes is a chronic autoimmune disease of beta cells in the islets of Langerhans, which are responsible for making insulin. Even with insulin therapy, inflammatory complications will develop in the long term. The present study examines changes in serum levels of interleukin (IL)-6, IL-17, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, C-peptide, Insulin as well as fasting blood sugar (FBS) in control, diabetic and diabetic treated with curcumin groups. Thirty inbred C57BL /6 mice were randomly divided into three groups of 10 mice: group A consisted of healthy mice receiving citrate buffer, group B included a group of diabetic mice, and group C was a group of diabetic mice treated with curcumin. The cytokine levels were measured in the supernatant of stimulated splenocytes using enzyme -linked immunosorbent assay (ELISA). Radioimmunoassay was used to measure insulin and c-peptide levels. The FBS was measured by an automatic glucometer device. The levels of IL-6, IL-17, and IFN-γ, as well as FBS, was significantly decreased in the treated group with curcumin compared to the diabetic group mice (p<0.05). TNF-α levels were also low, but the difference was not significant. IL-10, plasma C-peptide, and insulin significantly increased in the supernatant of stimulated splenocytes of treated diabetic group than in the diabetic group (p<0/05). According to the results, this study supports the anti-diabetic and anti-inflammatory effects of curcumin; however, more studies are needed to investigate theeffects of curcumin and the dose-response relationship in this disease. Topics: Animals; Anti-Inflammatory Agents; C-Peptide; Cells, Cultured; Curcumin; Cytokines; Diabetes Complications; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Humans; Inflammation Mediators; Insulin; Mice; Mice, Inbred C57BL; Spleen | 2020 |
Histological validation of a type 1 diabetes clinical diagnostic model for classification of diabetes.
Misclassification of diabetes is common due to an overlap in the clinical features of type 1 and type 2 diabetes. Combined diagnostic models incorporating clinical and biomarker information have recently been developed that can aid classification, but they have not been validated using pancreatic pathology. We evaluated a clinical diagnostic model against histologically defined type 1 diabetes.. We classified cases from the Network for Pancreatic Organ donors with Diabetes (nPOD) biobank as type 1 (n = 111) or non-type 1 (n = 42) diabetes using histopathology. Type 1 diabetes was defined by lobular loss of insulin-containing islets along with multiple insulin-deficient islets. We assessed the discriminative performance of previously described type 1 diabetes diagnostic models, based on clinical features (age at diagnosis, BMI) and biomarker data [autoantibodies, type 1 diabetes genetic risk score (T1D-GRS)], and singular features for identifying type 1 diabetes by the area under the curve of the receiver operator characteristic (AUC-ROC).. Diagnostic models validated well against histologically defined type 1 diabetes. The model combining clinical features, islet autoantibodies and T1D-GRS was strongly discriminative of type 1 diabetes, and performed better than clinical features alone (AUC-ROC 0.97 vs. 0.95; P = 0.03). Histological classification of type 1 diabetes was concordant with serum C-peptide [median < 17 pmol/l (limit of detection) vs. 1037 pmol/l in non-type 1 diabetes; P < 0.0001].. Our study provides robust histological evidence that a clinical diagnostic model, combining clinical features and biomarkers, could improve diabetes classification. Our study also provides reassurance that a C-peptide-based definition of type 1 diabetes is an appropriate surrogate outcome that can be used in large clinical studies where histological definition is impossible. Parts of this study were presented in abstract form at the Network for Pancreatic Organ Donors Conference, Florida, USA, 19-22 February 2019 and Diabetes UK Professional Conference, Liverpool, UK, 6-8 March 2019. Topics: Adult; Age of Onset; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Genetic Predisposition to Disease; Humans; Insulin; Islets of Langerhans; Male; Middle Aged; Pancreas; Reproducibility of Results; Young Adult; Zinc Transporter 8 | 2020 |
Functional β-Cell Differentiation of Small-Tail Han Sheep Pancreatic Mesenchymal Stem Cells and the Therapeutic Potential in Type 1 Diabetic Mice.
This study aims to investigate the characteristics of sheep pancreatic mesenchymal stem cells (PSCs) and therapeutic potential of differentiated β-like cells in streptozotocin-induced diabetic mice.. Pancreatic mesenchymal stem cells were isolated from 3- to 4-month-old sheep embryos, and their biological characteristics were explored. The function and therapeutic potential of differentiated β-like insulin-producing cells were also investigated in vitro and in vivo. Differentiated cells were identified through dithizone staining and immunofluorescence staining. Insulin secretion was analyzed using an enzyme-linked immunosorbent assay kit. The preliminary therapeutic potential of induced β-like cells in diabetic mice was detected by blood glucose and body weight.. Primary PSCs were isolated and subcultured up to passage 36. Immunofluorescence staining presented PSC-expressed important markers such as Pdx1, Nkx6-1, Ngn3, and Nestin. Primary PSCs could be induced into functional pancreatic β-like islet cells with a 3-step protocol. The induced β-like islet cells could ameliorate blood glucose in diabetic mice.. The method proposed for generating pancreatic islet β cells provided a preliminary phenotypic investigation of induced cell treatment in diabetic mice, and also laid a foundation in the identification of pharmaceutical targets to treat insulin-dependent diabetes. Topics: Animals; Blood Glucose; Body Weight; C-Peptide; Cell Differentiation; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucagon; Glucose; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Sheep | 2020 |
Liver nucleotide biosynthesis is linked to protection from vascular complications in individuals with long-term type 1 diabetes.
Identification of biomarkers associated with protection from developing diabetic complications is a prerequisite for an effective prevention and treatment. The aim of the present study was to identify clinical and plasma metabolite markers associated with freedom from vascular complications in people with very long duration of type 1 diabetes (T1D). Individuals with T1D, who despite having longer than 30 years of diabetes duration never developed major macro- or microvascular complications (non-progressors; NP) were compared with those who developed vascular complications within 25 years from diabetes onset (rapid progressors; RP) in the Scandinavian PROLONG (n = 385) and DIALONG (n = 71) cohorts. The DIALONG study also included 75 healthy controls. Plasma metabolites were measured using gas and/or liquid chromatography coupled to mass spectrometry. Lower hepatic fatty liver indices were significant common feature characterized NPs in both studies. Higher insulin sensitivity and residual ß-cell function (C-peptide) were also associated with NPs in PROLONG. Protection from diabetic complications was associated with lower levels of the glycolytic metabolite pyruvate and APOCIII in PROLONG, and with lower levels of thiamine monophosphate and erythritol, a cofactor and intermediate product in the pentose phosphate pathway as well as higher phenylalanine, glycine and serine in DIALONG. Furthermore, T1D individuals showed elevated levels of picolinic acid as compared to the healthy individuals. The present findings suggest a potential beneficial shunting of glycolytic substrates towards the pentose phosphate and one carbon metabolism pathways to promote nucleotide biosynthesis in the liver. These processes might be linked to higher insulin sensitivity and lower liver fat content, and might represent a mechanism for protection from vascular complications in individuals with long-term T1D. Topics: Aged; Biomarkers; Blood Glucose; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Humans; Insulin Resistance; Liver; Male; Metabolomics; Middle Aged; Nucleotides | 2020 |
Masked type 1 diabetes mellitus (T1DM) unveiled by glucocorticoid replacement: a case of simultaneous development of T1DM and hypophysitis in an elderly woman.
As a rare condition characterized by inflammation of the pituitary gland, hypophysitis usually results in hypopituitarism and pituitary enlargement. The most critical outcome of hypopituitarism is caused by secondary adrenal insufficiency. Glucocorticoid deficiency is a life-threatening condition, and patients who develop this deficiency require prompt diagnosis and treatment. However, a delayed diagnosis of hypopituitarism may occur due to its non-specific clinical manifestations. A common presenting sign of glucocorticoid deficiency is hypoglycemia. The amelioration of hyperglycemia has been observed in diabetic patients with adrenal insufficiency. We report the case of a 70-year-old Japanese woman who had suffered from fatigue and anorexia for several months; she was admitted based on refractory hyponatremia (sodium 125-128 mEq/L) and hypoglycemia (glucose 58-75 mg/dL). Laboratory findings and magnetic resonance imaging findings led to the diagnosis of panhypopituitarism caused by autoimmune hypophysitis. After receiving 10 mg/day of hydrocortisone, the patient developed severe hyperglycemia (glucose >500 mg/dL). Undetectable C-peptide levels and positive results of both insulinoma-associated antigen-2 antibodies and insulin autoantibodies indicated that she had experienced a recent onset of type 1 diabetes. The pathophysiological process indicated that overt hyperglycemia could be masked by the deficient action of glucocorticoids even in a diabetic patient with endogenous insulin deficiency. This uncommon case reinforces the importance of the prompt diagnosis and treatment of hypopituitarism. Clinicians should remain aware of the possibility of hidden diabetes when treating hypoglycemia in patients with adrenal insufficiency. Topics: Adrenal Insufficiency; Aged; Autoantibodies; Autoimmune Hypophysitis; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucocorticoids; Glycated Hemoglobin; Humans; Hydrocortisone; Hypoglycemic Agents; Hyponatremia; Hypopituitarism; Hypothyroidism; Insulin; Thyroxine | 2020 |
Detection of C-peptide in human hair and nail: a comparison between healthy persons and persons with type 1 diabetes.
Serum and urinary C-peptide has clinical implications in people with/without diabetes. Recently, C-peptide was detected in hair samples of healthy adults but not studied in people with diabetes. It is not known whether C-peptide can be detectable in nail tissue or not. This study aims to assess the detection of C-peptide in hair and nail samples and to find whether hair and nail C-peptide levels are different in type 1 diabetes mellitus (T1DM) compared with healthy individuals.. In a prospective case-control study on 41 subjects with T1DM and 42 control subjects, hair and nail samples were collected and prepared. C-peptide was extracted by incubating the samples with methanol and measuring the extract with an immunoassay. The hair and nail C-peptide values were compared between the T1DM and control group and their correlations with each other and with other variables were assessed with a significant level set at 0.05.. Hair and nail C-peptide levels were detected in both groups, with significantly lower values in T1DM compared with the control group. T1DM with >7-year diabetes duration had significantly lower C-peptide in serum, nails and hair. Hair and nail C-peptide levels have significant positive correlations with each other and negative correlations with age.. We conclude that C-peptide are detectable in the hair and nails of healthy persons and persons with T1DM. Compared with the healthy persons, persons with T1DM had significantly lower hair and nail C-peptide and significant hair/nail C-peptide reduction after 7 years of diagnosis. Our results suggest that hair and nails are suitable matrices for the measurement of C-peptide in healthy persons and persons with T1DM. Topics: Adult; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Humans; Nails; Prospective Studies | 2020 |
Type 1 diabetes in Africa: an immunogenetic study in the Amhara of North-West Ethiopia.
We aimed to characterise the immunogenic background of insulin-dependent diabetes in a resource-poor rural African community. The study was initiated because reports of low autoantibody prevalence and phenotypic differences from European-origin cases with type 1 diabetes have raised doubts as to the role of autoimmunity in this and similar populations.. A study of consecutive, unselected cases of recently diagnosed, insulin-dependent diabetes (n = 236, ≤35 years) and control participants (n = 200) was carried out in the ethnic Amhara of rural North-West Ethiopia. We assessed their demographic and socioeconomic characteristics, and measured non-fasting C-peptide, diabetes-associated autoantibodies and HLA-DRB1 alleles. Leveraging genome-wide genotyping, we performed both a principal component analysis and, given the relatively modest sample size, a provisional genome-wide association study. Type 1 diabetes genetic risk scores were calculated to compare their genetic background with known European type 1 diabetes determinants.. Patients presented with stunted growth and low BMI, and were insulin sensitive; only 15.3% had diabetes onset at ≤15 years. C-peptide levels were low but not absent. With clinical diabetes onset at ≤15, 16-25 and 26-35 years, 86.1%, 59.7% and 50.0% were autoantibody positive, respectively. Most had autoantibodies to GAD (GADA) as a single antibody; the prevalence of positivity for autoantibodies to IA-2 (IA-2A) and ZnT8 (ZnT8A) was low in all age groups. Principal component analysis showed that the Amhara genomes were distinct from modern European and other African genomes. HLA-DRB1*03:01 (p = 0.0014) and HLA-DRB1*04 (p = 0.0001) were positively associated with this form of diabetes, while HLA-DRB1*15 was protective (p < 0.0001). The mean type 1 diabetes genetic risk score (derived from European data) was higher in patients than control participants (p = 1.60 × 10. The majority of patients with insulin-dependent diabetes in rural North-West Ethiopia have the immunogenetic characteristics of autoimmune type 1 diabetes. Phenotypic differences between type 1 diabetes in rural North-West Ethiopia and the industrialised world remain unexplained. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Black People; C-Peptide; Child; Diabetes Mellitus, Type 1; Ethiopia; Female; Genome-Wide Association Study; HLA-DRB1 Chains; Humans; Male; Principal Component Analysis; Young Adult; Zinc Transporter 8 | 2020 |
Plasma circulating miR-23~27~24 clusters correlate with the immunometabolic derangement and predict C-peptide loss in children with type 1 diabetes.
We aimed to analyse the association between plasma circulating microRNAs (miRNAs) and the immunometabolic profile in children with type 1 diabetes and to identify a composite signature of miRNAs/immunometabolic factors able to predict type 1 diabetes progression.. Plasma samples were obtained from children at diagnosis of type 1 diabetes (n = 88) and at 12 (n = 32) and 24 (n = 30) months after disease onset and from healthy control children with similar sex and age distribution (n = 47). We quantified 60 robustly expressed plasma circulating miRNAs by quantitative RT-PCR and nine plasma immunometabolic factors with a recognised role at the interface of metabolic and immune alterations in type 1 diabetes. Based on fasting C-peptide loss over time, children with type 1 diabetes were stratified into the following groups: those who had lost >90% of C-peptide compared with diagnosis level; those who had lost <10% of C-peptide; those showing an intermediate C-peptide loss. To evaluate the modulation of plasma circulating miRNAs during the course of type 1 diabetes, logistic regression models were implemented and the correlation between miRNAs and immunometabolic factors was also assessed. Results were then validated in an independent cohort of children with recent-onset type 1 diabetes (n = 18). The prognostic value of the identified plasma signature was tested by a neural network-based model.. Plasma circulating miR-23~27~24 clusters (miR-23a-3p, miR-23b-3p, miR-24-3p, miR-27a-3p and miR-27b-3p) were upmodulated upon type 1 diabetes progression, showed positive correlation with osteoprotegerin (OPG) and were negatively correlated with soluble CD40 ligand, resistin, myeloperoxidase and soluble TNF receptor in children with type 1 diabetes but not in healthy children. The combination of plasma circulating miR-23a-3p, miR-23b-3p, miR-24-3p, miR-27b-3p and OPG, quantified at disease onset, showed a significant capability to predict the decline in insulin secretion 12 months after disease diagnosis in two independent cohorts of children with type 1 diabetes.. We have pinpointed a novel miR-23a-3p/miR-23b-3p/miR-24-3p/miR-27b-3p/OPG plasma signature that may be developed into a novel blood-based method to better stratify patients with type 1 diabetes and predict C-peptide loss. Topics: C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Humans; MicroRNAs; Osteoprotegerin | 2020 |
Efficacy of GAD-alum immunotherapy associated with HLA-DR3-DQ2 in recently diagnosed type 1 diabetes.
The aim of this study was to determine if retention of C-peptide following immunotherapy using recombinant GAD65 conjugated to aluminium hydroxide (GAD-alum) is influenced by HLA risk haplotypes DR3-DQ2 and DR4-DQ8.. HLA-dependent treatment effect of GAD-alum therapy on C-peptide retention in individuals with recent-onset type 1 diabetes was evaluated using individual-level patient data from three placebo-controlled, randomised clinical trials using a mixed repeated measures model.. A significant and dose-dependent effect was observed in individuals positive for the genotypes that include HLA-DR3-DQ2 but not HLA-DR4-DQ8 and in the broader subgroup of individuals positive for all genotypes that include HLA-DR3-DQ2 (i.e. including those also positive for HLA-DR4-DQ8). Higher doses (three or four injections) showed a treatment effect ratio of 1.596 (95% CI 1.132, 2.249; adjusted p = 0.0035) and 1.441 (95% CI 1.188, 1.749; adjusted p = 0.0007) vs placebo for the two respective HLA subgroups.. GAD65-specific immunotherapy has a significant effect on C-peptide retention in individuals with recent-onset type 1 diabetes who have the DR3-DQ2 haplotype. Graphical abstract. Topics: Adjuvants, Immunologic; Aluminum Hydroxide; C-Peptide; Desensitization, Immunologic; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Haplotypes; HLA-DQ Antigens; HLA-DR3 Antigen; HLA-DR4 Antigen; Humans; Immunotherapy; Randomized Controlled Trials as Topic; Treatment Outcome | 2020 |
Comparing Beta Cell Preservation Across Clinical Trials in Recent-Onset Type 1 Diabetes.
Several immunotherapies have demonstrated endogenous insulin preservation in recent-onset type 1 diabetes (T1D). We considered the primary results of rituximab, abatacept, teplizumab, alefacept, high-dose antithymocyte globulin (ATG), low-dose ATG, and low-dose ATG ± granulocyte-colony-stimulating factor trials in an attempt to rank the effectiveness of the agents studied. C-peptide 2-h area under the curve means were modeled using analysis of covariance. The experimental treatment group effect for each study, compared with its internal control, was estimated after adjusting for baseline C-peptide and age. Percentage increase in C-peptide over placebo and the absolute difference within study were calculated to compare and contrast effect size among interventions. Low-dose ATG (55% and 103%) and teplizumab (48% and 63%) ranked highest in C-peptide preservation at 1 and 2 years, respectively. Low-dose ATG and teplizumab show the greatest impact on C-peptide preservation among recent new-onset T1D studies; these should be further explored as core immunotherapies in the T1D prevention setting. Topics: Abatacept; Alefacept; Antibodies, Monoclonal, Humanized; Antilymphocyte Serum; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Granulocyte Colony-Stimulating Factor; Humans; Immunotherapy; Insulin; Insulin-Secreting Cells; Rituximab | 2020 |
Subtypes of Type 2 Diabetes Determined From Clinical Parameters.
Type 2 diabetes (T2D) is defined by a single metabolite, glucose, but is increasingly recognized as a highly heterogeneous disease, including individuals with varying clinical characteristics, disease progression, drug response, and risk of complications. Identification of subtypes with differing risk profiles and disease etiologies at diagnosis could open up avenues for personalized medicine and allow clinical resources to be focused to the patients who would be most likely to develop diabetic complications, thereby both improving patient health and reducing costs for the health sector. More homogeneous populations also offer increased power in experimental, genetic, and clinical studies. Clinical parameters are easily available and reflect relevant disease pathways, including the effects of both genetic and environmental exposures. We used six clinical parameters (GAD autoantibodies, age at diabetes onset, HbA Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Humans; Insulin Resistance; Male | 2020 |
The Pathological Evolution of Glucose Response Curves During the Progression to Type 1 Diabetes in the TrialNet Pathway to Prevention Study.
Glucose response curves (GRCs) during oral glucose tolerance tests (OGTTs) are predictive of type 1 diabetes. We performed a longitudinal analysis in pancreatic autoantibody-positive individuals to assess. Among antibody-positive individuals with serial OGTTs in the TrialNet Pathway to Prevention study, GRC changes from first to last OGTTs were compared between progressors (. GRCs changed more frequently from biphasic (two peaks) to monophasic (one peak) GRCs between first and last OGTTs in progressors than in nonprogressors (75.4% vs. 51.0%, respectively;. Characteristic GRC changes, biphasic to monophasic to monotonic, occur during the progression to type 1 diabetes. These GRC changes correspond to decreasing β-cell function. Topics: Adolescent; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Family; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin-Secreting Cells; Longitudinal Studies; Male; Pancreas; Young Adult | 2020 |
Systemic TNFα correlates with residual β-cell function in children and adolescents newly diagnosed with type 1 diabetes.
Type 1 diabetes (T1D) is caused by immune-mediated destruction of the β-cells. After initiation of insulin therapy many patients experience a period of improved residual β-cell function leading to partial disease remission. Cytokines are important immune-modulatory molecules and contribute to β-cell damage in T1D. The patterns of systemic circulating cytokines during T1D remission are not clear but may constitute biomarkers of disease status and progression. In this study, we investigated if the plasma levels of various pro- and anti-inflammatory cytokines around time of diagnosis were predictors of remission and residual β-cell function in children with T1D followed for one year after disease onset.. In a cohort of 63 newly diagnosed children (33% females) with T1D with a mean age of 11.3 years (3.3-17.7), ten cytokines were measured of which eight were detectable in plasma samples by Mesoscale Discovery multiplex technology at study start and after 6 and 12 months. Linear regression models were used to evaluate association of cytokines with stimulated C-peptide.. Systemic levels of tumor necrosis factor (TNF)-α, interleukin (IL)-2 and IL-6 inversely correlated with stimulated C-peptide levels over the entire study (P < 0.05). The concentrations of TNFα and IL-10 at study start predicted stimulated C-peptide level at 6 months (P = 0.011 and P = 0.043, respectively, adjusted for sex, age, HbA1c and stage of puberty).. In recent-onset T1D, systemic cytokine levels, and in particular that of TNFα, correlate with residual β-cell function and may serve as prognostic biomarkers of disease remission and progression to optimize treatment strategies.. The study was performed according to the criteria of the Helsinki II Declaration and was approved by the Danish Capital Region Ethics Committee on Biomedical Research Ethics (journal number H-3-2014-052). The parents of all participants gave written consent. Topics: Adolescent; C-Peptide; Child; Cytokines; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin-Secreting Cells; Male; Tumor Necrosis Factor-alpha | 2020 |
Type 1 diabetes can present before the age of 6 months and is characterised by autoimmunity and rapid loss of beta cells.
Diabetes diagnosed at <6 months of age is usually monogenic. However, 10-15% of affected infants do not have a pathogenic variant in one of the 26 known neonatal diabetes genes. We characterised infants diagnosed at <6 months of age without a pathogenic variant to assess whether polygenic type 1 diabetes could arise at early ages.. We studied 166 infants diagnosed with type 1 diabetes at <6 months of age in whom pathogenic variants in all 26 known genes had been excluded and compared them with infants with monogenic neonatal diabetes (n = 164) or children with type 1 diabetes diagnosed at 6-24 months of age (n = 152). We assessed the type 1 diabetes genetic risk score (T1D-GRS), islet autoantibodies, C-peptide and clinical features.. We found an excess of infants with high T1D-GRS: 38% (63/166) had a T1D-GRS >95th centile of healthy individuals, whereas 5% (8/166) would be expected if all were monogenic (p < 0.0001). Individuals with a high T1D-GRS had a similar rate of autoantibody positivity to that seen in individuals with type 1 diabetes diagnosed at 6-24 months of age (41% vs 58%, p = 0.2), and had markedly reduced C-peptide levels (median <3 pmol/l within 1 year of diagnosis), reflecting rapid loss of insulin secretion. These individuals also had reduced birthweights (median z score -0.89), which were lowest in those diagnosed with type 1 diabetes at <3 months of age (median z score -1.98).. We provide strong evidence that type 1 diabetes can present before the age of 6 months based on individuals with this extremely early-onset diabetes subtype having the classic features of childhood type 1 diabetes: high genetic risk, autoimmunity and rapid beta cell loss. The early-onset association with reduced birthweight raises the possibility that for some individuals there was reduced insulin secretion in utero. Comprehensive genetic testing for all neonatal diabetes genes remains essential for all individuals diagnosed with diabetes at <6 months of age. Graphical abstract. Topics: Autoimmunity; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Genetic Testing; Humans; Infant; Infant, Newborn; Insulin-Secreting Cells; Male | 2020 |
Confirmation and Identification of Biomarkers Implicating Environmental Triggers in the Pathogenesis of Type 1 Diabetes.
Topics: Adipokines; Age of Onset; Antibodies, Viral; Autoantibodies; Biomarkers; C-Peptide; Case-Control Studies; Child; Cross-Sectional Studies; Cytokines; Diabetes Mellitus, Type 1; Environmental Exposure; Enzyme-Linked Immunosorbent Assay; Female; Humans; Intercellular Signaling Peptides and Proteins; Lipopolysaccharide Receptors; Macrophage Activation; Macrophages; Male; Monocytes | 2020 |
A C-peptide complex with albumin and Zn
People with type 1 diabetes (T1D) require exogenous administration of insulin, which stimulates the translocation of the GLUT4 glucose transporter to cell membranes. However, most bloodstream cells contain GLUT1 and are not directly affected by insulin. Here, we report that C-peptide, the 31-amino acid peptide secreted in equal amounts with insulin in vivo, is part of a 3-component complex that affects red blood cell (RBC) membranes. Multiple techniques were used to demonstrate saturable and specific C-peptide binding to RBCs when delivered as part of a complex with albumin. Importantly, when the complex also included Zn Topics: Adenosine Triphosphate; Animals; Biological Transport; C-Peptide; Cattle; Cell Membrane; Diabetes Mellitus, Type 1; Erythrocytes; Gene Expression Regulation; Glucose; Glucose Transporter Type 1; Humans; Insulin; Serum Albumin, Bovine; Zinc | 2020 |
Glutamic Acid Decarboxylase Injection Into Lymph Nodes: Beta Cell Function and Immune Responses in Recent Onset Type 1 Diabetes Patients.
clinicaltrials.gov, identifier NCT02352974. Topics: Administration, Oral; Adolescent; Aluminum Hydroxide; C-Peptide; CD8-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Immunity; Immunoglobulin G; Injections, Intralymphatic; Insulin-Secreting Cells; Interleukin-10; Lymph Nodes; Lymphocyte Activation; Male; Signal Transduction; Treatment Outcome; Vitamin D; Vitamins; Young Adult | 2020 |
Heterogeneity in the aetiology of diabetes mellitus in young adults: A prospective study from north India.
In contrast to Caucasians of European origin, the aetiology of diabetes mellitus (DM) in young adults in other ethnic groups, including Indians is likely to be heterogeneous and difficult to determine. This study was undertaken to determine the aetiology of diabetes in young Indian adults using a protocol-based set of simple clinical and investigation tools.. In this prospective study, 105 Indian young adults with diabetes (age at onset 18-35 yr; duration <2 yr) were studied for a period of 1-3 years. Pancreatic imaging, fasting C-peptide, islet antibodies (against glutamic acid decarboxylase, tyrosine phosphatase and zinc transporter-8) and mitochondrial A3243G mutational analysis were performed in all patients. Four patients were screened for maturity-onset diabetes of the young (MODY) using next-generation sequencing.. Type 1 and type 2 diabetes mellitus (T1DM and T2DM) were equally frequent (40% each), followed by fibrocalculous pancreatic diabetes (FCPD, 15%). Less common aetiologies included MODY (2%), mitochondrial diabetes (1%) and Flatbush diabetes (2%). There was considerable phenotypic overlap between the main aetiological subtypes. Elevated islet antibodies were noted in 62 per cent of T1DM patients [positive predictive value (PPV) 84%; negative predictive value (NPV) 78%] while low plasma C-peptide (<250 pmol/l) was present in 56 per cent of T1DM patients [PPV 96% (after excluding FCPD), NPV 72%]. Using these tests and observing the clinical course over one year, a final diagnosis was made in 103 (99%) patients, while the diagnosis at recruitment changed in 23 per cent of patients.. The aetiology of diabetes in young adults was heterogeneous, with T1DM and T2DM being equally common. FCPD was also frequent, warranting its screening in Indian patients. Testing for islet antibodies and C-peptide in this age group had good PPV for diagnosis of T1DM. Topics: Adolescent; Adult; Age of Onset; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; India; Islets of Langerhans; Male; Pancreas; Prospective Studies; Young Adult | 2019 |
[Clinical features for hospitalized type 1 diabetic patients with different ages of onset].
To explore the clinical features and complications of 545 hospitalized type 1 diabetic patients. Methods: All data of 545 patients with typical type 1 diabetes (T1DM) who were hospitalized in the Department of Endocrinology, the Second Xiangya Hospital, Central South University were collected. The data were analyzed retrospectively to explore the clinical features and complications. Clinical and biochemical characteristics were analyzed through comparison between different subgroups according to the onset age (≤13 years old, 14-29 years old, ≥30 years old). Results: The median onset age of T1DM patients was 27.0 (15.0, 40.0) years, and the middle-onset was 42.1%. Among the 3 groups, the proportion of female (58.0%) was the highest in the ≤13 years old group, concomitant with the lowest SBP and serum creatinine levels as well as the lowest incidence of all microvascular complications (21.0% of diabetic nephropathy, 23.3% of diabetic retinopathy, 34.1% of diabetic peripheral neuropathy; all P<0.05). Moreover, the fasting C peptide and peak C peptide levels were the lowest in ≥30 years old group compared with the other two groups, and the incidence of ketosis (33.5%) and all macrovascular complications were the highest among the three groups (all P<0.05). Conclusion: There are about half of the hospitalized patients with T1DM whose onset ages are ≥30 years. The incidence of ketosis at the onset and the risk for various microvascular and macrovascular complications after onset are higher than those with the onset age <30 years.. 目的:探讨1型糖尿病(type 1 diabetes,T1DM)住院患者的临床特征和并发症情况。方法:回顾性分析545例T1DM住院患者的临床资料,按照不同起病年龄(≤13岁、14~29岁、≥30岁)分析患者的临床特征和并发症情况。结果:545例T1DM患者的中位起病年龄为27.0(15.0,40.0)岁,≥30岁起病者占42.8%。与其他两组比较,≤13岁组女性比例(58.0%)较高,收缩压和血肌酐水平均最低,且所有微血管并发症的发生率(糖尿病肾病21.0%,糖尿病视网膜病变23.3%,糖尿病周围神经病变34.1%)均最低(均P<0.05);与其他两组比较,≥30岁组空腹C肽及峰值C肽水平均最低,起病时酮症的发生率(33.5%)及大血管并发症的发生率均最高(均P<0.05)。结论:在T1DM住院患者中≥30岁起病者约占一半,起病时酮症的发生率及起病后各种微血管及大血管并发症的风险均较<30岁起病者更高。. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Humans; Male; Retrospective Studies; Risk Factors; Young Adult | 2019 |
Persistent C-peptide secretion in Type 1 diabetes and its relationship to the genetic architecture of diabetes.
The objective of this cross-sectional study was to explore the relationship of detectable C-peptide secretion in type 1 diabetes to clinical features and to the genetic architecture of diabetes.. C-peptide was measured in an untimed serum sample in the SDRNT1BIO cohort of 6076 Scottish people with clinically diagnosed type 1 diabetes or latent autoimmune diabetes of adulthood. Risk scores at loci previously associated with type 1 and type 2 diabetes were calculated from publicly available summary statistics.. Prevalence of detectable C-peptide varied from 19% in those with onset before age 15 and duration greater than 15 years to 92% in those with onset after age 35 and duration less than 5 years. Twenty-nine percent of variance in C-peptide levels was accounted for by associations with male gender, late age at onset and short duration. The SNP heritability of residual C-peptide secretion adjusted for gender, age at onset and duration was estimated as 26%. Genotypic risk score for type 1 diabetes was inversely associated with detectable C-peptide secretion: the most strongly associated loci were the HLA and INS gene regions. A risk score for type 1 diabetes based on the HLA DR3 and DQ8-DR4 serotypes was strongly associated with early age at onset and inversely associated with C-peptide persistence. For C-peptide but not age at onset, there were strong associations with risk scores for type 1 and type 2 diabetes that were based on SNPs in the HLA region but not accounted for by HLA serotype.. Persistence of C-peptide secretion varies widely in people clinically diagnosed as type 1 diabetes. C-peptide persistence is influenced by variants in the HLA region that are different from those determining risk of early-onset type 1 diabetes. Known risk loci for diabetes account for only a small proportion of the genetic effects on C-peptide persistence. Topics: Adolescent; Adult; Age of Onset; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Disease Progression; Female; Genotype; HLA-DQ Antigens; Humans; Male; Risk Factors; Young Adult | 2019 |
C-peptide persistence in type 1 diabetes: 'not drowning, but waving'?
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin | 2019 |
Systematic Assessment of Immune Marker Variation in Type 1 Diabetes: A Prospective Longitudinal Study.
Immune analytes have been widely tested in efforts to understand the heterogeneity of disease progression, risk, and therapeutic responses in type 1 diabetes (T1D). The future clinical utility of such analytes as biomarkers depends on their technical and biological variability, as well as their correlation with clinical outcomes. To assess the variability of a panel of 91 immune analytes, we conducted a prospective study of adults with T1D (<3 years from diagnosis), at 9-10 visits over 1 year. Autoantibodies and frequencies of T-cell, natural killer cell, and myeloid subsets were evaluated; autoreactive T-cell frequencies and function were also measured. We calculated an intraclass correlation coefficient (ICC) for each marker, which is a relative measure of between- and within-subject variability. Of the 91 analytes tested, we identified 35 with high between- and low within-subject variability, indicating their potential ability to be used to stratify subjects. We also provide extensive data regarding technical variability for 64 of the 91 analytes. To pilot the concept that ICC can be used to identify analytes that reflect biological outcomes, the association between each immune analyte and C-peptide was also evaluated using partial least squares modeling. CD8 effector memory T-cell (CD8 EM) frequency exhibited a high ICC and a positive correlation with C-peptide, which was also seen in an independent dataset of recent-onset T1D subjects. More work is needed to better understand the mechanisms underlying this relationship. Here we find that there are a limited number of technically reproducible immune analytes that also have a high ICC. We propose the use of ICC to define within- and between-subject variability and measurement of technical variability for future biomarker identification studies. Employing such a method is critical for selection of analytes to be tested in the context of future clinical trials aiming to understand heterogeneity in disease progression and response to therapy. Topics: Adolescent; Adult; Autoantibodies; Biomarkers; C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Immunologic Memory; Killer Cells, Natural; Longitudinal Studies; Male; Middle Aged; Myeloid Cells; Prospective Studies; T-Lymphocytes; Young Adult | 2019 |
Persistent elevations in circulating INS DNA among subjects with longstanding type 1 diabetes.
To evaluate whether β cells continue to undergo death in the later stages of type 1 diabetes (T1D).. Fasting banked sera from a cross-section of 90 participants in the T1D Exchange Registry with longstanding T1D (median duration of 9 years) were analysed. Subjects were determined to be C-peptide (-) or (+) based on mixed-meal tolerance testing. Results were compared with 54 adult non-diabetic controls. Stimulated samples were assayed in a subset of subjects. Levels of unmethylated and methylated preproinsulin (INS) DNA were analysed using digital droplet PCR.. Fasting and stimulated circulating unmethylated INS DNA levels were increased among both C-peptide (-) and C-peptide (+) subjects with longstanding T1D compared with non-diabetic controls (P < 0.01). Consistent with prior reports, unmethylated INS DNA values correlated with methylated INS DNA values, which were also elevated among T1D subjects (P < 0.001). There was wide variation in the effects of mixed-meal stimulation on DNA levels, with fasting values in the highest quartiles decreasing with stimulation (P < 0.05).. These results could reflect ongoing β cell death in individuals with longstanding T1D, even in the absence of detectable C-peptide production, suggesting that therapies targeting β cell survival could be beneficial among individuals with longstanding T1D. Topics: Adult; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; DNA; DNA Methylation; Female; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Protein Precursors; Young Adult | 2019 |
Hyaluronan levels are increased systemically in human type 2 but not type 1 diabetes independently of glycemic control.
Hyaluronan (HA), an extracellular matrix glycosaminoglycan, is implicated in the pathogenesis of both type 1 diabetes (T1D) as well as type 2 diabetes (T2D) and has been postulated to be increased in these diseases due to hyperglycemia. We have examined the serum and tissue distribution of HA in human subjects with T1D and T2D and in mouse models of these diseases and evaluated the relationship between HA levels and glycemic control. We found that serum HA levels are increased in T2D but not T1D independently of hemoglobin-A1c, C-peptide, body mass index, or time since diabetes diagnosis. HA is likewise increased in skeletal muscle in T2D subjects relative to non-diabetic controls. Analogous increases in serum and muscle HA are seen in diabetic db/db mice (T2D), but not in diabetic DORmO mice (T1D). Diabetes induced by the β-cell toxin streptozotozin (STZ) lead to an increase in blood glucose but not to an increase in serum HA. These data indicate that HA levels are increased in multiple tissue compartments in T2D but not T1D independently of glycemic control. Given that T2D but not T1D is associated with systemic inflammation, these patterns are consistent with inflammatory factors and not hyperglycemia driving increased HA. Serum HA may have value as a biomarker of systemic inflammation in T2D. Topics: Adult; Animals; Body Mass Index; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Hyaluronic Acid; Male; Mice; Muscle, Skeletal; Streptozocin; Young Adult | 2019 |
Physical activity is associated with lower insulin and C-peptide during glucose challenge in children and adolescents with family background of diabetes.
Children and adolescents with a family history of diabetes are at increased risk of overweight, but little is known about the potentially beneficial effects of physical activity on these children. The objective of this study was to investigate the association between moderate to vigorous physical activity (MVPA) and metabolic and inflammatory risks in children and adolescents with a family background of Type 1 diabetes or gestational diabetes.. Valid MVPA measurements, made with accelerometers, were available from 234 participants (median age, 10.2 years) who had a first-degree relative with either Type 1 or gestational diabetes. Anthropometric and metabolic measurements were made and cytokines measured, and were correlated with MVPA measurements, with stepwise adjustment for confounding factors, in a cross-sectional analysis.. MVPA was negatively associated with insulin and C-peptide during challenge with an oral glucose tolerance test. MVPA was also significantly positively associated with the insulin sensitivity index, whereas no consistently significant associations were found between MVPA and BMI, blood pressure or cytokine levels.. Our findings indicate that physical activity may have beneficial effects on insulin and C-peptide metabolism in children and adolescents with a family background of diabetes, but show no evidence of a protective association with other health-related outcomes. Topics: Adolescent; C-Peptide; Child; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes, Gestational; Exercise; Female; Germany; Glucose; Glucose Tolerance Test; Humans; Insulin; Male; Medical History Taking; Pregnancy; Risk Factors | 2019 |
Development of a double-antibody sandwich ELISA for rapid detection to C-peptide in human urine.
C-peptide level is recognized as an important indicator of diabetes diagnosis. A sensitive and specific double-antibody sandwich enzyme-linked immunosorbent assay for the detection of C-peptide based on double antibody sandwich method was studied in this paper. The rabbit and hen were innunized with PLL-C-peptide and BSA-C-peptide respectively to obtain specific Yolk antibody (IgY) and polyclonal antibody used to construct the sandwich ELISA for the measurement of C-peptide. The limit of detection was 0.51 μg/mL and the half maximal inhibitory concentration (IC50) was 3.26 μg/mL. The method developed in the study showed no evident cross-reactivity with other similar analogs. The detection standard curve of C-peptide exhibited a good linearity (R Topics: Adult; Aged; Antibodies; Antibody Specificity; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Enzyme-Linked Immunosorbent Assay; Female; Humans; Limit of Detection; Male; Middle Aged; Predictive Value of Tests; Reproducibility of Results; Time Factors; Urinalysis; Workflow; Young Adult | 2019 |
Proinsulin C-peptide as an alternative or combined treatment with insulin for management of testicular dysfunction and fertility impairments in streptozotocin-induced type 1 diabetic male rats.
Diabetes mellitus (DM) is closely associated with male infertility and sexual dysfunction. Recent data indicate that the proinsulin C-peptide (CP) exerts important physiological effects and shows the characteristics of an endogenous peptide hormone. So, this study was done to investigate the effect of C-peptide with or without insulin treatment on testicular function and architecture in diabetic rats. Rats were divided into the following groups: control, diabetic, and diabetic groups treated with either CP alone or combined with insulin. Tested parameters included, estimation of serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and glucose levels, testicular samples for histopathology and estimation of malondialdehyde (MDA), total antioxidant capacity (TAC), and B-cell leukemia/lymphoma-2 (BCL-2) levels as well as sperm count and motility. Results showed that DM caused a severe alteration in hormonal profile and reduced sperm parameters along with increased MDA and decrease in both TAC and BCL-2 levels. CP alone or with insulin treatment efficiently reversed all the negative effects of DM on rat testes, with maximum improvement in the combined regimen. Proposed mechanisms may involve its hypoglycemic, antioxidant, and antiapoptotic properties. Thus, CP could substitute for or better combined with insulin to prevent or retard diabetic-induced testicular dysfunction. Topics: Animals; Apoptosis; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Infertility, Male; Insulin; Male; Oxidative Stress; Rats; Sperm Count; Streptozocin; Testis | 2019 |
Impact of Type 1 and Type 2 Diabetes Mellitus on Pancreas Transplant Outcomes.
Pancreas transplant improves quality of life and survival of patients irrespective of pretransplant C-peptide levels. Our objectives were to examine complications and outcomes in patients without measureable C-peptide (insulin-dependent type 1 diabetes mellitus) and carefully selected patients with measurable C-peptide (insulin-dependent type 2 diabetes mellitus) after pancreas transplant.. We conducted a retrospective analysis to examine the demographic, transplant factors, complications, and outcomes in patients with nondetectable pretransplant C-peptide (insulin-dependent type 1 diabetes mellitus) and patients with detectable pretransplant C-peptide (insulin-dependent type 2 diabetes mellitus).. Of 214 consecutive pancreas transplant procedures over a 12-year period, 112 had pretransplant C-peptide level testing (63 patients with type 1 and 49 with type 2 diabetes mellitus). Patients with type 1 disease were more likely to be female (P = .048), and patients with type 2 disease were more likely to be African American (P < .001) and have undergone previous pancreas transplant (P = .042). We observed no differences in donor factors or posttransplant factors (C-peptide after year 2, glucose, and hemoglobin A1C, except that patients with type 2 disease had more pancreatitis) (P = .036). There were no differences in posttransplant complications; however, patients with type 2 disease had significantly higher BK virus nephropathy (P = .006). There were no differences in outcomes between cohorts (rejection, graft loss, or death; P = not significant).. Pancreas transplant can be performed with excellent and equivalent outcomes in patients with type 1 and carefully selected type 2 diabetes mellitus. Patients with type 2 disease are more likely to have posttransplant pancreatitis and BK virus nephropathy, affecting the net benefit for transplant. Topics: Adolescent; Adult; Biomarkers; BK Virus; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Immunocompromised Host; Kidney Diseases; Male; Opportunistic Infections; Pancreas Transplantation; Pancreatitis; Polyomavirus Infections; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome; Tumor Virus Infections; Young Adult | 2019 |
Addition of glucagon-like peptide-1 receptor agonist therapy to insulin in C-peptide-positive patients with type 1 diabetes.
We aimed to test the hypothesis that addition of glucagon-like peptide-1 receptor agonists (GLP-1RAs) to insulin in C-peptide-positive patients with type 1 diabetes (T1D) will result in a reduction in glycated haemoglobin (HbA1c) with reduced insulin requirements and a rise in C-peptide concentrations. We conducted a retrospective analysis of 11 normal-weight patients with T1D consecutively treated with a GLP-1RA in addition to insulin. Paired t tests were used to compare the changes in HbA1c, insulin doses, body weight, body mass index, and C-peptide concentrations prior to and 12 ± 1 weeks after GLP-1RA therapy. At the end of 12 ± 1 weeks of GLP-1RA therapy, HbA1c fell from 10.74 ± 0.96% (95 ± 10.5 mmol/mol) to 7.4 ± 0.58% (58 ± 6.3mmol/mol) (P < 0.01), body weight fell from 71 ± 2.0 to 69 ± 2 kg (P = 0.06), and total insulin dose was reduced by 64% from 33 ± 6 to 11 ± 5 units (P < 0.01). Five out of 10 patients did not require any insulin. C-peptide concentrations increased significantly from 0.43 ± 0.09 ng/ml (0.14 ± 0.02 nmol/L) to 1.42 ± 0.42ng/ml (0.47 ± 0.13 nmol/L) (P = 0.01). Addition of GLP-1RA therapy to insulin in normal-weight patients with T1D led to a reduction in HbA1c with reduced insulin requirements, a 3.5-fold increase in C-peptide concentrations and freedom from insulin therapy in 50% of patients who tolerated the GLP-1RA therapy over a period of 12 ± 1 weeks. Topics: Adult; Autoantibodies; Body Weight; C-Peptide; Deprescriptions; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptides; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunoglobulin Fc Fragments; Insulin; Liraglutide; Male; Middle Aged; Recombinant Fusion Proteins; Retrospective Studies; Treatment Outcome; Weight Loss | 2019 |
Treatment of type 1 diabetes with teplizumab: clinical and immunological follow-up after 7 years from diagnosis.
The long-term effects of successful immune therapies for treatment of type 1 diabetes have not been well studied. The Autoimmunity-Blocking Antibody for Tolerance (AbATE) trial evaluated teplizumab, an Fc receptor non-binding humanised anti-CD3 monoclonal antibody in individuals with new-onset type 1 diabetes, and ended in 2011. Clinical drug-treated responders showed an increased frequency of 'partially exhausted' CD8. Participants with detectable C-peptide at year 2 of AbATE returned for follow-up. C-peptide responses were assessed by 4 h mixed-meal tolerance test. Autoantibodies and HbA. Fifty-six per cent of the original participants returned. Three of the original control group who did not return had lost all detectable C-peptide by the end of the 2 year trial. The C-peptide responses to a mixed-meal tolerance test were similar overall in the drug vs control group of participants but were significantly improved, with less loss of C-peptide, in drug-treated responders identified at 1 year. However, the improvements in C-peptide response were not associated with lower HbA. These findings suggest there is reduced decline in C-peptide and persistent immunological responses up to 7 years after diagnosis of diabetes in individuals who respond to teplizumab.. ClinicalTrials.gov NCT02067923; the protocol is available at www.immunetolerance.org (ITN027AI). Topics: Adolescent; Adult; Antibodies, Monoclonal, Humanized; Area Under Curve; Autoimmunity; C-Peptide; CD3 Complex; CD8-Positive T-Lymphocytes; Child; Cytokines; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Male; Randomized Controlled Trials as Topic; Remission Induction; Treatment Outcome; Young Adult | 2019 |
Inappropriate glucagon and GLP-1 secretion in individuals with long-standing type 1 diabetes: effects of residual C-peptide.
Recent studies have demonstrated that residual beta cells may be present in some people with long-standing type 1 diabetes, but little is known about the potential impact of this finding on alpha cell function and incretin levels. This study aimed to evaluate whether insulin microsecretion could modulate glucagon and glucagon-like peptide-1 (GLP-1) responses to a mixed meal tolerance test (MMTT).. Adults with type 1 diabetes onset after the age of 15 years (n = 29) underwent a liquid MMTT after an overnight fast. Insulin microsecretion was defined when peak C-peptide levels were >30 pmol/l using an ultrasensitive assay. Four individuals with recent-onset type 1 diabetes were included as controls. Glucagon and GLP-1 responses were analysed according to C-peptide patterns.. We found comparable peak values, Δ. The glucagon response to an MMTT in people with long-standing type 1 diabetes is not reduced by the presence of residual beta cells. The reduction of GLP-1 responses according to residual C-peptide levels suggests specific regulatory pathways. Topics: Adult; Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Secreting Cells; Glucose Tolerance Test; Humans; Incretins; Insulin; Insulin-Secreting Cells; Male; Young Adult | 2019 |
Challenges in the classification and management of Asian youth-onset diabetes mellitus- lessons learned from a single centre study.
It remains widely perceived that early-onset Type 2 Diabetes (T2D) in children and adolescents is rare and clinically distinct from Type 1 Diabetes (T1D). We studied the challenges of classifying subtypes of early-onset diabetes using clinical features and biomarkers, and management of these patients. We reviewed retrospectively the record of patients < 25 years old who attended the diabetes clinic in Penang General Hospital, Malaysia between 1st December 2012 and 30th June 2015. We examined their clinical features, C-peptide and pancreatic autoantibodies. Comparisons were made between T1D and T2D for magnitude, demographics, metabolic status and complications. We studied 176 patients with a mean age of 20 ± 3.7 years, 43.2% had T1D, 13.6% had T2D, and 13.6% had mixed features of both. When tested, pancreatic autoantibodies were positive in 59.4% of the T1D. T2D presented two years later than T1D at 14.3 years, 20% were asymptomatic at presentation, and 50% required insulin supplementation despite fasting c-peptide of > 250 pmol/L. HbA1C of ≤ 8.0% (64 mmol/mol) was achieved in 30.3% of T1D, 58.3% of T2D on OAD and 16.7% of T2D on insulin. The T2D had greater cardiovascular risk with higher body mass index, more dyslipidaemia, higher blood pressure and earlier onset of nephropathy. The overlapping clinical features, variable autoimmunity, and beta-cell loss complicate classification of young diabetes. Pancreatic autoantibodies and C-peptide did not always predict diabetes subtypes nor respond to insulin. The poor metabolic control and high cardiovascular risk burden among the T2D highlight the need for population-based study and focused intervention. Topics: Adolescent; Age of Onset; Autoantibodies; C-Peptide; Cardiovascular Diseases; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Malaysia; Male; Pancreas; Retrospective Studies; Young Adult | 2019 |
Clinical features, biochemistry and HLA-DRB1 status in youth-onset type 1 diabetes in Pakistan.
Published information on diabetes in Pakistani youth is limited. We aimed to investigate the demographic, clinical, and biochemical features, and HLA-DRB1 alleles in new cases of diabetes affecting children and adolescents <22 years of age. The study was conducted at Baqai Institute of Diabetology and Endocrinology in Karachi from June 2013-December 2015. One hundred subjects aged <22 years at diagnosis were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, glutamic acid decarboxylase 65 (GAD65) and islet antigen 2 (IA-2) autoantibodies) were measured. DNA from 100 subjects and 200 controls was extracted and genotyped for HLA-DRB1 using high-resolution genotyping technology. Ninety-nine subjects were clinically diagnosed as type 1 diabetes (T1D) and one as type 2 diabetes (T2D). Of the 99 with T1D, 57 (57.6%) were males and 42 (42.4%) females, with mean age at diagnosis 11.0 ± 5.2 years (range 1.6-21.7 years) and peaks at six and fifteen years. Fifty-seven subjects were assessed within one month of diagnosis and all within eleven months. For the subjects diagnosed as T1D, mean C-peptide was 0.63 ± 0.51 nmol/L (1.91 ± 1.53 ng/mL), with 16 (16.2%) IA2 positive, 53 (53.5%) GAD-65 positive, and 10 (10.1%) positive for both autoantibodies. In T1D patients, the allele DRB1*03:01 demonstrated highly significant T1D association (p < 10 Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA-DRB1 Chains; Humans; Infant; Male; Pakistan; Young Adult | 2019 |
Prenatal Betamethasone interferes with immune system development and alters target cells in autoimmune diabetes.
Non-genetic factors are crucial in the pathogenesis of type 1 diabetes (T1D), a disease caused by autoimmunity against insulin-producing β-cells. Exposure to medications in the prenatal period may influence the immune system maturation, thus altering self-tolerance. Prenatal administration of betamethasone -a synthetic glucocorticoid given to women at risk of preterm delivery- may affect the development of T1D. It has been previously demonstrated that prenatal betamethasone administration protects offspring from T1D development in nonobese diabetic (NOD) mice. The direct effect of betamethasone on the immature and mature immune system of NOD mice and on target β-cells is analysed in this paper. In vitro, betamethasone decreased lymphocyte viability and induced maturation-resistant dendritic cells, which in turn impaired γδ T cell proliferation and decreased IL-17 production. Prenatal betamethasone exposure caused thymus hypotrophy in newborn mice as well as alterations in immune cells subsets. Furthermore, betamethasone decreased β-cell growth, reduced C-peptide secretion and altered the expression of genes related to autoimmunity, metabolism and islet mass in T1D target tissue. These results support the protection against T1D in the betamethasone-treated offspring and demonstrate that this drug alters the developing immune system and β-cells. Understanding how betamethasone generates self-tolerance could have potential clinical relevance in T1D. Topics: Animals; Autoimmunity; Betamethasone; C-Peptide; Cell Survival; Diabetes Mellitus, Type 1; Disease Models, Animal; Female; Glucocorticoids; Humans; Immune Tolerance; Inclusion Bodies; Insulin-Secreting Cells; Lymphocyte Activation; Maternal Exposure; Mice; Mice, Inbred NOD; Obstetric Labor, Premature; Pregnancy | 2019 |
Tapering decay of β-cell function in Chinese patients with autoimmune type 1 diabetes: A four-year prospective study.
This study investigated the natural progression of β-cell function in Chinese autoimmune type 1 diabetic (T1D) patients and clarified factors possibly influencing the course of the disease.. The natural progression of β-cell function of 325 newly diagnosed Chinese autoimmune T1D patients was assessed by fasting and postprandial C-peptide (FCP and PCP, respectively) levels. β-Cell function failure was defined as FCP <50 pM and PCP <100 pM, whereas preserved β-cell function was defined as FCP >200 pM or PCP >400 pM. β-Cell function that did not meet these criteria was described as residual.. At initial recruitment, 33.3% of patients had β-cell function failure, whereas 41.0% and 25.8% of patients had preserved or residual β-cell function, respectively. The percentage of patients who developed β-cell function failure during follow-up at 12, 24, 36, and 48 months after recruitment to the study was 55.8%, 75.6%, 86.7%, and 92.7%, respectively. Moreover, the slope of the β-cell function curve decreased over time, indicating that the pattern of its decline was non-linear and tapering. Seven percent of patients did not develop β-cell function failure within 4 years after diagnosis. Patients with lower initial FCP levels were more likely to develop β-cell function failure.. Chinese autoimmune T1D patients have considerable residual β-cell function at initial diagnosis, and the manner of progression of β-cell function failure is non-linear with a tapering decay rate. Furthermore, initial FCP levels may predict β-cell function failure in Chinese autoimmune T1D patients.. 摘要: 背景 本研究探索了中国自身免疫1型糖尿病患者胰岛功能衰退模式,并寻找可能影响疾病进程的因素。 方法 入组325例初诊自身免疫1型糖尿病患者,随访观察其空腹C肽(FCP)和餐后C肽(PCP)的变化。FCP<50pmol/L且PCP<100pmol/L定义为β细胞功能衰竭,FCP>200pmol/L或PCP>400pmol/L定义为β细胞功能保留,FCP、PCP水平介于上述范围之间定义为β细胞功能残余。 结果 入组时,33%的患者β细胞功能衰竭,41%的患者β功能保留,25.8%的患者β细胞功能残余。入组后第12、24、36、48个月随访时,胰岛β细胞功能衰竭的患者比例分别达到55.8%、75.6%、86.7%和92.7%。β细胞功能随时间变化曲线呈现出非线性特征,其斜率随时间逐渐变小。入组后4年内随访时仍有约7%的患者β细胞功能未衰竭。入组FCP水平越低,患者在随访过程中越容易出现β细胞功能衰竭。 结论 中国自身免疫1型糖尿病患者初诊时胰岛β细胞功能尚可,诊后β细胞功能下降的速度呈现出非线性的先快后慢特征。初诊FCP水平可作为预测患者胰岛β细胞功能衰竭的指标。. Topics: Adult; Asian People; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Insulin; Insulin-Secreting Cells; Male; Prognosis; Prospective Studies; Young Adult | 2019 |
Persistent C-peptide is associated with reduced hypoglycaemia but not HbA
Most people with Type 1 diabetes have low levels of persistent endogenous insulin production. The Diabetes Control and Complications Trial showed that close to diagnosis preserved endogenous insulin was associated with lower HbA. We conducted a cross-sectional case-control study of 221 people (median age 24 years) with Type 1 diabetes. We confirmed ongoing endogenous insulin secretion by measuring C-peptide after a mixed-meal tolerance test. We compared self-reported hypoglycaemia (n = 160), HbA. Adults with Type 1 diabetes and preserved endogenous insulin production receiving usual care in the UK have lower daily insulin doses and fewer self-reported hypoglycaemic episodes, but no difference in HbA Topics: Adolescent; Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Case-Control Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Male; Practice Patterns, Physicians'; United Kingdom; Young Adult | 2019 |
Type 1 diabetes defined by severe insulin deficiency occurs after 30 years of age and is commonly treated as type 2 diabetes.
Late-onset type 1 diabetes can be difficult to identify. Measurement of endogenous insulin secretion using C-peptide provides a gold standard classification of diabetes type in longstanding diabetes that closely relates to treatment requirements. We aimed to determine the prevalence and characteristics of type 1 diabetes defined by severe endogenous insulin deficiency after age 30 and assess whether these individuals are identified and managed as having type 1 diabetes in clinical practice.. We assessed the characteristics of type 1 diabetes defined by rapid insulin requirement (within 3 years of diagnosis) and severe endogenous insulin deficiency (non-fasting C-peptide <200 pmol/l) in 583 participants with insulin-treated diabetes, diagnosed after age 30, from the Diabetes Alliance for Research in England (DARE) population cohort. We compared characteristics with participants with retained endogenous insulin secretion (>600 pmol/l) and 220 participants with severe insulin deficiency who were diagnosed under age 30.. Twenty-one per cent of participants with insulin-treated diabetes who were diagnosed after age 30 met the study criteria for type 1 diabetes. Of these participants, 38% did not receive insulin at diagnosis, of whom 47% self-reported type 2 diabetes. Rapid insulin requirement was highly predictive of severe endogenous insulin deficiency: 85% required insulin within 1 year of diagnosis, and 47% of all those initially treated without insulin who progressed to insulin treatment within 3 years of diagnosis had severe endogenous insulin deficiency. Participants with late-onset type 1 diabetes defined by development of severe insulin deficiency had similar clinical characteristics to those with young-onset type 1 diabetes. However, those with later onset type 1 diabetes had a modestly lower type 1 diabetes genetic risk score (0.268 vs 0.279; p < 0.001 [expected type 2 diabetes population median, 0.231]), a higher islet autoantibody prevalence (GAD-, islet antigen 2 [IA2]- or zinc transporter protein 8 [ZnT8]-positive) of 78% at 13 years vs 62% at 26 years of diabetes duration; (p = 0.02), and were less likely to identify as having type 1 diabetes (79% vs 100%; p < 0.001) vs those with young-onset disease.. Type 1 diabetes diagnosed over 30 years of age, defined by severe insulin deficiency, has similar clinical and biological characteristics to that occurring at younger ages, but is frequently not identified. Clinicians should be aware that patients progressing to insulin within 3 years of diagnosis have a high likelihood of type 1 diabetes, regardless of initial diagnosis. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Middle Aged | 2019 |
Comment on Sims et al. Proinsulin Secretion Is a Persistent Feature of Type 1 Diabetes. Diabetes Care 2019;42:258-264.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Proinsulin | 2019 |
Response to Comment on Sims et al. Proinsulin Secretion Is a Persistent Feature of Type 1 Diabetes. Diabetes Care 2019;42:258-264.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Proinsulin | 2019 |
Poor Glycemic Control Is Associated With Impaired Bone Accrual in the Year Following a Diagnosis of Type 1 Diabetes.
Type 1 diabetes (T1D) is associated with an increased fracture risk across the life course. The effects on bone accrual early in the disease are unknown.. To characterize changes in bone density and structure over the year following diagnosis of T1D and to identify contributors to impaired bone accrual.. Prospective cohort study.. Academic children's hospital.. Thirty-six children, ages 7 to 17 years, enrolled at diagnosis of T1D.. Whole body and regional dual-energy X-ray absorptiometry and tibia peripheral quantitative computed tomography obtained at baseline and 12 months. The primary outcome was bone accrual assessed by bone mineral content (BMC) and areal bone mineral density (aBMD) velocity z score.. Participants had low total body less head (TBLH) BMC (z = -0.46 ± 0.76), femoral neck aBMD (z = -0.57 ± 0.99), and tibia cortical volumetric BMD (z = -0.44 ± 1.11) at diagnosis, compared with reference data, P < 0.05. TBLH BMC velocity in the year following diagnosis was lower in participants with poor (hemoglobin A1c ≥7.5%) vs good (hemoglobin A1c <7.5%) glycemic control at 12 months, z = -0.36 ± 0.84 vs 0.58 ± 0.71, P = 0.003. TBLH BMC velocity was correlated with gains in tibia cortical area (R = 0.71, P = 0.003) and periosteal circumference (R = 0.67, P = 0.007) z scores in participants with good, but not poor control.. Our results suggest that the adverse effects of T1D on BMD develop early in the disease. Bone accrual following diagnosis was impaired in participants with poor glycemic control and appeared to be mediated by diminished bone formation on the periosteal surface. Topics: Adolescent; Bone and Bones; Bone Density; Bone Development; C-Peptide; Cancellous Bone; Child; Cortical Bone; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Male; Organ Size; Osteogenesis; Periosteum | 2019 |
Study of the difficult glycemic control in relation to the presence of diabetes-autoantibodies in a sample of Egyptians with type 1 diabetes.
T1DM is divided into 1A (immune-mediated), 1B (virus-triggered, genetic and idiopathic). Presence of auto-antibodies may be correlated to glycemic control.. Assessment relation between the autoantibodies and the poor glycemic control in T1DM.. 60 patients T1DM 30 males, 30 females, subjected to full history, clinical, anthropometric assessment and laboratory assessment of fasting C-peptide, FBS, 2 h PP glucose, HbA1c, GADA, ICA and IAA level. Classified into two groups; Group I: negative auto-antibodies, Group II: positive auto-antibodies, Group II was further classified into 3 sub-groups, Group II a:1 positive autoantibody, Group II b: 2 positive autoantibodies and Group II c: 3 positive autoantibodies.. HbA1c was significantly higher in group II than group I (11.85 ± 1.61% vs. 8.52 ± 0.41%, p = 0.000). HbA1c was highest in group IIc followed by IIb then IIa (12.25 ± 1.48% vs. 11.57 ± 1.59% vs. 10.78 ± 1.73%, p = 0.038). Total insulin units per day was significantly higher in group II than group I (109.83 ± 7.77 U/day vs. 100.83 ± 1.83 U/day, p = 0.007). Duration of diabetes was significantly higher in group I than group II (10.17 ± 1.94 years vs. 8.11 ± 2.20 years, p = 0.033). HbA1c, total insulin units per day and duration of diabetes were independent predictive factors for presence of autoantibodies (p = 0.007, p = 0.033 and p = 0.043 respectively).. Autoantibodies affect the glycemic control presented by high HbA1c; also it causes increase in total insulin units needed by patients; the more autoantibodies, the higher HbA1c, the more insulin units required to control glycemic state. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Egypt; Female; Glutamate Decarboxylase; Humans; Insulin; Insulin Antibodies; Male; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Young Adult | 2019 |
A study of 51 subtypes of peripheral blood immune cells in newly diagnosed young type 1 diabetes patients.
Type 1 diabetes (T1D) results from autoimmune destruction of insulin-producing beta cells in pancreatic islets. Various immune cell populations are involved in disease development and natural course. However, to our knowledge, so far there are no comprehensive comparative investigations of all main immune cell populations and their most important subsets at the onset of disease. Therefore, in the current study, we analyzed 51 peripheral blood immune cell populations in 22 young T1D patients and in 25 age-matched controls using a comprehensive polychromatic flow cytometry panel developed for whole blood by the COST Action no. BM0907 ENTIRE (European Network for Translational Immunology Research and Education: From Immunomonitoring to Personalized Immunotherapy) consortium. We found that in T1D patients, frequencies and absolute counts of natural killer (NK) cells, dendritic cells (DC) and T cells, as well as their respective subsets, were significantly altered compared to controls. Further, we observed that changes in several cell populations (e.g. CD14 Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Dendritic Cells; Diabetes Mellitus, Type 1; Female; Flow Cytometry; Humans; Immunotherapy; Insulin; Insulin-Secreting Cells; Ketosis; Killer Cells, Natural; Leukocytes, Mononuclear; Male; Monocytes; Young Adult | 2019 |
[Clinical characteristics and classification diagnosis of newly diagnosed diabetes onset with ketosis or ketoacidosis in adult patients].
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Ketosis; Male; Middle Aged | 2019 |
Metabolic Imbalance and Vitamin D Deficiency in Type 1 Diabetes in the Algerian Population.
We aimed to assess Vitamin D levels in patients with Type 1 Diabetes (T1D) and to investigate the correlation between vitamin D and metabolic imbalance.. For our study, we selected thirty-one patients with T1D without complications and fifty-seven healthy controls. Diabetic patients were diagnosed using the criteria of the World Health Organization/American Diabetes Association. Vitamin D, Parathyroid Hormone (PTH), insulin and C peptide assay were performed using chimilunescence. Glucose level, lipid profile, glycated haemoglobin (HbA1c) and ionogram were also analysed.. Vitamin D, HbA1c and Gly levels were found to be significant in T1D patients than in controls (P<0.5). However, for PTH, no significant difference was observed (P > 0. 05) and the results show a non-significant difference of total cholesterol potassium, sodium, phosphor and calcium concentration averages.. Our results indicate that the deficiency of VD is associated with an increased risk of T1DM in Algerian population. Topics: Adult; Algeria; Biomarkers; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Energy Metabolism; Female; Glycated Hemoglobin; Humans; Insulin; Male; Parathyroid Hormone; Risk Factors; Vitamin D; Vitamin D Deficiency; Young Adult | 2019 |
Identification of Novel T1D Risk Loci and Their Association With Age and Islet Function at Diagnosis in Autoantibody-Positive T1D Individuals: Based on a Two-Stage Genome-Wide Association Study.
Type 1 diabetes (T1D) is a highly heritable disease with much lower incidence but more adult-onset cases in the Chinese population. Although genome-wide association studies (GWAS) have identified >60 T1D loci in Caucasians, less is known in Asians.. We performed the first two-stage GWAS of T1D using 2,596 autoantibody-positive T1D case subjects and 5,082 control subjects in a Chinese Han population and evaluated the associations between the identified T1D risk loci and age and fasting C-peptide levels at T1D diagnosis.. We observed a high genetic correlation between children/adolescents and adult T1D case subjects (. Our results extend current knowledge on genetic contributions to T1D risk. Further investigations in different populations are needed for genetic heterogeneity and subsequent precision medicine. Topics: Adolescent; Adult; Age Factors; Antigens, CD; Asian People; Autoantibodies; Butyrophilins; C-Peptide; Child; China; Diabetes Mellitus, Type 1; Fasting; Female; GATA3 Transcription Factor; Genetic Loci; Genome-Wide Association Study; Histocompatibility Antigens Class I; Humans; Male; Odds Ratio; Oxidoreductases Acting on Sulfur Group Donors; Risk Factors | 2019 |
Persistent C-peptide levels and microvascular complications in childhood onset type 1 diabetes of long duration.
The aim was to determine if persistent c-peptide in long duration childhood onset (<17 years) type 1 diabetes (T1D) related to microvascular complications.. Pittsburgh Epidemiology of Diabetes Complications (EDC) participants (n = 185) had serum c-peptide levels measured by Mercodia ultra-sensitive ELISA at the 25-year follow-up exam. Microvascular complications between those with and without detectable c-peptide were compared.. Eighteen (9.7%) participants had detectable median c-peptide levels of 3.8 (2.6, 12.2) pmol/L and did not differ from those without detectable levels. No differences in microalbuminuria, confirmed distal symmetric polyneuropathy, renal failure, or between those with one or more complications were found between the two groups. Proliferative retinopathy (PR) was marginally lower in those with detectable c-peptide (33.3% vs 55.1%, p = 0.08). However, those with c-peptide were somewhat less likely to have fasted for a full 8-h (66.7% vs. 84.9%, p = 0.09). Excluding those not fully fasted, PR no longer approached significance but macroalbuminuria became marginally lower in those with detectable levels (23.4% vs 0%, p = 0.07).. Low levels of c-peptide in T1D patients of long duration were detected but were not strongly related to microvascular complications. Topics: Adolescent; Adult; Albuminuria; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Male; Risk Factors; Time Factors; Young Adult | 2019 |
A Patient with Nivolumab-related Fulminant Type 1 Diabetes Mellitus whose Serum C-peptide Level Was Preserved at the Initial Detection of Hyperglycemia.
A 77-year-old-man with renal cell carcinoma who was undergoing nivolumab treatment visited our department due to hyperglycemia; his plasma glucose level was 379 mg/dL. Although his serum C-peptide immunoreactivity (CPR) level was preserved (5.92 ng/mL), we suspected an onset of fulminant type 1 diabetes mellitus (FT1DM) and immediately started insulin therapy. His CPR levels gradually decreased and were depleted within 1 week. We later discovered that the patient's casual CPR level had been abnormally high (11.78 ng/mL) 2 weeks before his admission. Hence, the possibility of FT1DM in hyperglycemic patients undergoing nivolumab treatment should not be excluded, even with a preserved CPR level. Topics: Aged; Antibodies, Monoclonal; Antineoplastic Agents, Immunological; Blood Glucose; C-Peptide; Carcinoma, Renal Cell; Diabetes Mellitus, Type 1; Humans; Hyperglycemia; Insulin; Kidney Neoplasms; Male; Nivolumab | 2019 |
Insulin: still a miracle after all these years.
The discovery of insulin almost 100 years ago has resulted in a remarkable increase in lifespan and quality of life for patients with type 1 diabetes. The Joslin Medalist Study has allowed researchers to access and study patients (Medalists) with type 1 diabetes who have been insulin dependent for 50 years or more. In this issue of the JCI, Yu et al. evaluated HLA variants, autoantibody status, β cell function, C-peptide release, and monogenetic diabetes genes in a cohort of Medalists. Postmortem analysis of pancreata from Medalists revealed the presence of insulin-positive β cells in these patients. Moreover, some patients were still able to respond to metabolic stimuli despite long-term insulin dependence. Overall, the Medalist cohort was highly heterogenous, and genetic testing suggested that several patients would fall into categories other than type 1 diabetes on the basis of REVEL (rare exome variant ensemble learner) classification and may be able to transfer to other therapy options. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Quality of Life; Time Factors | 2019 |
Children with type 1 diabetes of early age at onset - immune and metabolic phenotypes.
Objectives We aimed to evaluate children with type 1 diabetes (T1D) with early age at onset (EAO) for clinical, immune and metabolic features in order to identify age-related disease phenotypes. Methods Comparative study of two groups of T1D children: EAO (≤5 years) and later age at onset (LAO; >5 years), regarding the presence of other autoimmune (AI) diseases, diabetes ketoacidosis and immunologic profile at onset and metabolic data 1 year after diagnosis. Statistical analysis was performed with significance set for p < 0.05. Results The study included 137 children (EAO = 52, mean age 3.6 ± 1.5 [mean ± standard deviation (SD)] and LAO = 85, mean age 10.4 ± 2.9). EAO was more associated with concomitant AI diseases (p = 0.032). Despite no differences in disease onset, EAO presented with lower C-peptide levels (p = 0.01) and higher absolute lymphocyte number (p < 0.0001), with an inverse correlation between these two variables (p = 0.028). Additionally, the EAO group had a higher frequency of serum detection of three antibodies (Abs) (p = 0.0008), specifically insulin Abs (p = 0.0001). One year after diagnosis, EAO had higher total daily insulin (TDI) dose (p = 0.008), despite similar hemoglobin A1c (HbA1c). Conclusions Our data show an association of EAO T1D with more AI diseases, higher number of Abs, lower initial insulin reservoir and higher insulin requirements 1 year after diagnosis. In this group, immune imbalance seems more evident and disease progression faster, probably reflecting distinct "immune environment" with different ages at disease onset. Further studies in the field of immunogenetics and immune tolerance are required, to improve patient stratification and find novel targets for therapeutic intervention. Topics: Adolescent; Age of Onset; Autoantibodies; Autoimmune Diseases; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Infant; Infant, Newborn; Insulin; Male; Phenotype; Prognosis; Retrospective Studies | 2019 |
Clinical determinants of the remission phase in children with new-onset type 1 diabetes mellitus in two years of observation.
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Exercise; Glycated Hemoglobin; Humans; Infant; Remission, Spontaneous | 2019 |
Aggravation of diabetes, and incompletely deficient insulin secretion in a case with type 1 diabetes-resistant human leukocyte antigen DRB1*15:02 treated with nivolumab.
Anti-programmed cell death-1 (PD-1) antibody therapy induces various adverse effects, especially in the endocrine system. Several cases of acute-onset insulin-dependent diabetes after anti-PD-1 antibody therapy have been reported. Many of these cases have a susceptible human leukocyte antigen (HLA) genotype for type 1 diabetes, possibly suggesting that HLA might be involved in the onset of diabetes with anti-PD-1 therapy. We describe an atypical case of hyperglycemia after anti-PD-1 antibody administration. A 68-year-old Japanese man with pancreatic diabetes and steroid diabetes was given nivolumab three times for chemoresistant adenocarcinoma of the lung. On day 5 after the third infusion of nivolumab, he had hyperglycemia (blood glucose 330 mg/dL and hemoglobin A1c 8.0%) without ketosis and with incompletely deficient insulin secretion. The patient had both type 1 diabetes susceptible (HLA-A*24:02 and -DRB1*09:01) and resistant (HLA-DRB1*15:02) HLA genotypes. These HLA genotypes differ from those previously reported in anti-PD-1 antibody-induced diabetes, and might have influenced the preservation of insulin secretion after nivolumab administration in the present case. Topics: Aged; Antibodies, Monoclonal; Antineoplastic Agents; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; HLA Antigens; Humans; Hyperglycemia; Insulin; Insulin Secretion; Lung Neoplasms; Male; Nivolumab | 2018 |
The shape of the glucose concentration curve during an oral glucose tolerance test predicts risk for type 1 diabetes.
We aimed to examine: (1) whether specific glucose-response curve shapes during OGTTs are predictive of type 1 diabetes development; and (2) the extent to which the glucose-response curve is influenced by insulin secretion.. Autoantibody-positive relatives of people with type 1 diabetes whose baseline OGTT met the definition of a monophasic or biphasic glucose-response curve were followed for the development of type 1 diabetes (n = 2627). A monophasic curve was defined as an increase in OGTT glucose between 30 and 90 min followed by a decline of ≥ 0.25 mmol/l between 90 and 120 min. A biphasic response curve was defined as a decrease in glucose after an initial increase, followed by a second increase of ≥ 0.25 mmol/l. Associations of type 1 diabetes risk with glucose curve shapes were examined using cumulative incidence curve comparisons and proportional hazards regression. C-peptide responses were compared with and without adjustments for potential confounders.. The majority of participants had a monophasic curve at baseline (n = 1732 [66%] vs n = 895 [34%]). The biphasic group had a lower cumulative incidence of type 1 diabetes (p < 0.001), which persisted after adjustments for age, sex, BMI z score and number of autoantibodies (p < 0.001). Among the monophasic group, the risk of type 1 diabetes was greater for those with a glucose peak at 90 min than for those with a peak at 30 min; the difference persisted after adjustments (p < 0.001). Compared with the biphasic group, the monophasic group had a lower early C-peptide (30-0 min) response, a lower C-peptide index (30-0 min C-peptide/30-0 min glucose), as well as a greater 2 h C-peptide level (p < 0.001 for all).. Those with biphasic glucose curves have a lower risk of progression to type 1 diabetes than those with monophasic curves, and the risk among the monophasic group is increased when the glucose peak occurs at 90 min than at 30 min. Differences in glucose curve shapes between the monophasic and biphasic groups appear to be related to C-peptide responses. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Male; Middle Aged | 2018 |
Random non-fasting C-peptide testing can identify patients with insulin-treated type 2 diabetes at high risk of hypoglycaemia.
The aim of this study was to determine whether random non-fasting C-peptide (rCP) measurement can be used to assess hypoglycaemia risk in insulin-treated type 2 diabetes.. We compared continuous glucose monitoring-assessed SD of blood glucose and hypoglycaemia duration in 17 patients with insulin-treated type 2 diabetes and severe insulin deficiency (rCP < 200 pmol/l) and 17 matched insulin-treated control patients with type 2 diabetes but who had preserved endogenous insulin (rCP > 600 pmol/l). We then assessed the relationship between rCP and questionnaire-based measures of hypoglycaemia in 256 patients with insulin-treated type 2 diabetes and a comparison group of 209 individuals with type 1 diabetes.. Continuous glucose monitoring (CGM)-assessed glucose variability and hypoglycaemia was greater in individuals with rCP < 200 pmol/l despite similar mean glucose. In those with low vs high C-peptide, SD of glucose was 4.2 (95% CI 3.7, 4.6) vs 3.0 (2.6, 3.4) mmol/l (p < 0.001). In the low-C-peptide vs high-C-peptide group, the proportion of individuals experiencing sustained hypoglycaemia ≤ 4 mmol/l was 94% vs 41% (p < 0.001), the mean rate of hypoglycaemia was 5.5 (4.4, 6.7) vs 2.1 (1.4, 2.9) episodes per person per week (p = 0.004) and the mean duration was 630 (619, 643) vs 223 (216, 230) min per person per week (p = 0.01). Hypoglycaemia ≤ 3 mmol/l was infrequent in individuals with preserved C-peptide (1.8 [1.2, 2.6] episodes per person per week vs 0.4 [0.1, 0.8] episodes per person per week for low vs high C-peptide, p = 0.04) and only occurred at night. In a population-based cohort with insulin-treated type 2 diabetes, self-reported hypoglycaemia was twice as frequent in those with rCP < 200 pmol/l (OR 2.0, p < 0.001) and the rate of episodes resulting in loss of consciousness or seizure was five times higher (OR 5.0, p = 0.001). The relationship between self-reported hypoglycaemia and C-peptide was similar in individuals with type 1 and type 2 diabetes.. Low rCP is associated with increased glucose variability and hypoglycaemia in patients with insulin-treated type 2 diabetes and represents a practical, stable and inexpensive biomarker for assessment of hypoglycaemia risk. Topics: Aged; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Male | 2018 |
Complete loss of insulin secretion capacity in type 1A diabetes patients during long-term follow up.
Patients with type 1 diabetes are classified into three subtypes in Japan: acute onset, fulminant and slowly progressive. Acute-onset type 1 diabetes would be equivalent to type 1A diabetes, the typical type 1 diabetes in Western countries. The insulin secretion capacity in Japanese patients with long-standing type 1A diabetes is unclear. The aim of the present study was to clarify the course of endogenous insulin secretion during long-term follow up and the factors associated with residual insulin secretion in patients with acute-onset type 1 diabetes (autoimmune).. We retrospectively investigated endogenous insulin secretion capacity in 71 patients who fulfilled the diagnostic criteria for acute-onset type 1 diabetes (autoimmune) in Japan. To assess the residual insulin secretion capacity, we evaluated randomly measured C-peptide levels and the results of glucagon stimulation test in 71 patients.. In the first year of disease, the child- and adolescent-onset patients had significantly more in residual insulin secretion than the adult-onset patients (34 patients in total). C-peptide levels declined more rapidly in patients whose age of onset was ≤18 years than in patients whose age of onset was ≥19 years. Endogenous insulin secretion capacity stimulated by glucagon was completely lost in almost all patients at >15 years after onset (61 patients in total).. Most patients with acute-onset type 1 diabetes (autoimmune) completely lose their endogenous insulin secretion capacity during the disease duration in Japan. Age of onset might affect the course of insulin secretion. Topics: Adult; Age of Onset; Asian People; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Humans; Insulin; Insulin Secretion; Japan; Male; Retrospective Studies; Young Adult | 2018 |
Differential associations of lower cardiac vagal tone with insulin resistance and insulin secretion in recently diagnosed type 1 and type 2 diabetes.
It is unclear to which extent altered insulin sensitivity/secretion contribute to the development of diabetic cardiovascular autonomic neuropathy (CAN) characterized by diminished heart rate variability (HRV). We hypothesised that lower HRV is differentially associated with measures of insulin resistance and insulin secretion in recent-onset type 1 and type 2 diabetes.. This cross-sectional study included participants from the German Diabetes Study with type 1 (n=275) or type 2 diabetes (n=450) with known diabetes duration ≤1year and glucose-tolerant controls (n=81). Four time domain and frequency domain HRV measures each, reflecting vagal and/or sympathetic modulation were determined over 3h during a hyperinsulinaemic-euglycaemic clamp. Insulin sensitivity was calculated as the M-value, while insulin secretion was determined by glucagon-stimulated incremental C-peptide (ΔC-peptide).. After adjustment for sex, age, BMI, smoking, and HbA1c, both M-value and ΔC-peptide were lower in the diabetes groups compared to controls (P<0.05). In multiple linear regression analyses after Bonferroni correction, vagus-mediated HRV indices were positively associated with M-value in both diabetes types (P<0.05) and inversely associated with ΔC-peptide only in participants with type 1 diabetes (P<0.05). In type 2 diabetes, the low-frequency/high-frequency (LF/HF) power as an indicator of sympathovagal balance was weakly inversely associated with M-value.. Insulin resistance may contribute to the development of early cardiovagal suppression rather than sympathetic predominance in both diabetes types, while in type 1 diabetes a lower glucagon-stimulated insulin secretion is linked to a possibly compensatory higher parasympathetic tone. Whether interventions aimed at reducing insulin resistance could also reduce the risk of CAN remains to be established. Topics: Adolescent; Adult; Aged; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glucose Clamp Technique; Heart; Heart Rate; Humans; Insulin; Insulin Resistance; Lipids; Male; Middle Aged; Vagus Nerve; Young Adult | 2018 |
Generation of insulin-producing cells from human adipose-derived mesenchymal stem cells on PVA scaffold by optimized differentiation protocol.
The studies have been done on patient-specific human adipose-derived from mesenchymal stem cells (hADSCs) like a series of autologous growth factors and nanofibrous scaffolds (3D culture) will probably have many benefits for regenerative medicine in type 1 diabetes mellitus (TIDM) patients in the future. For this purpose, we established a polyvinyl alcohol (PVA) scaffold and a differentiation protocol by adding platelet-rich plasma (PRP) that induces the hADSCs into insulin-producing cells (IPCs). The characteristics of the derived IPCs in 3D culture were compared with conventional culture (2D) groups evaluated at the mRNA and protein levels. The viability of induced pancreatic cells was 14 days. The in vitro studies showed that the treatment of hADSCs in the 3D culture resulted in differentiated cells with strong characteristics of IPCs including pancreatic-like cells, the expression of the islet-associated genes at the mRNA and protein levels in comparison of 2D culture group. Furthermore, the immunoassay tests showed that these differentiated cells in these two groups are functional and secreted C-peptide and insulin in a glucose stimulation challenge. The results of our study for the first time demonstrated that the PVA nanofibrous scaffolds along with the optimized differentiation protocol with PRP can enhance the differentiation of IPCs from hADSCs. In conclusion, this study provides a new approach to the future pancreatic tissue engineering and beta cell replacement therapies for T1DM. Topics: Adipocytes; Adult; Blood Donors; C-Peptide; Cell Culture Techniques; Cell Differentiation; Diabetes Mellitus, Type 1; Gene Expression Regulation; Glucose; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Mesenchymal Stem Cells; Platelet-Rich Plasma; Polyvinyl Alcohol; Tissue Scaffolds | 2018 |
Islet damage during isolation as assessed by miRNAs and the correlation of miRNA levels with posttransplantation outcome in islet autotransplantation.
High-quality pancreatic islets are essential for better posttransplantation endocrine function in total pancreatectomy with islet autotransplantation (TPIAT), yet stress during the isolation process affects quality and yield. We analyzed islet-enriched microRNAs (miRNAs) -375 and -200c released during isolation to assess damage and correlated the data with posttransplantation endocrine function. The absolute concentration of miR-375, miR-200c, and C-peptide was measured in various islet isolation steps, including digestion, dilution, recombination, purification, and bagging, in 12 cases of TPIAT. Posttransplantation glycemic control was monitored through C-peptide, hemoglobin A Topics: Adult; Blood Glucose; C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Endocrine System; Female; Follow-Up Studies; Graft Rejection; Graft Survival; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; MicroRNAs; Postoperative Complications; Risk Factors; Transplantation, Autologous; Treatment Outcome | 2018 |
Comparative evaluation of simple indices using a single fasting blood sample to estimate beta cell function after islet transplantation.
Six single fasting blood sample-based indices-Secretory Unit of Islet Transplant Objects (SUITO), Transplant Estimated Function (TEF), Homeostasis Model Assessment (HOMA)2-B%, C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr), and BETA-2 score-were compared against commonly used 90-minute mixed meal tolerance test (MMTT) serum glucose and beta score to assess which of them best recognizes the state of acceptable blood glucose control without insulin supplementation after islet allotransplantation (ITx). We also tested whether the indices could identify the success of ITx based on the Igls classification of beta cell graft function. We analyzed values from 47 MMTT tests in 4 patients with up to 140 months follow-up and from 54 MMTT tests in 13 patients with up to 42 months follow-up. SUITO, CP/G, HOMA2-B%, and BETA-2 correlated well with the 90-minute glucose of the MMTT and beta-score (r 0.54-0.76), whereas CP/GCr showed a modest performance (r 0.41-0.52) while TEF showed little correlation. BETA-2 and SUITO were the best identifiers and predictors of the need for insulin support, glucose intolerance, and ITx success (P < .001), while HOMA2-B% and TEF were unreliable. Single fasting blood sample SUITO and BETA-2 scores are very practical alternative tools that allow for frequent assessments of graft function. Topics: Adult; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Fasting; Female; Follow-Up Studies; Glucose Tolerance Test; Graft Survival; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Prognosis | 2018 |
Association between Antioxidant Enzyme Activities and Enterovirus-Infected Type 1 Diabetic Children.
To examine the effect of infection with Enterovirus (EV) in children with type 1 diabetes (T1D) on the activities of serum antioxidant enzymes in diabetic and nondiabetic controls.. Three hundred and eighty-two diabetic and 100 nondiabetic children were tested for EV RNA using reverse transcriptase (RT)-PCR. The activities of serum superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were also estimated in diabetic patients infected with EV (T1D-EV+), those not infected with EV (T1D-EV-), and in nondiabetic controls.. The frequency of EV was higher in diabetic children (100/382; 26.2%) than in healthy controls (0/100). Levels of fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c) and C-reactive protein (CRP) were significantly higher but C-peptide was significantly lower in diabetic children than in controls. CRP levels were higher in the T1D-EV+ group than in the T1D-EV- group, and higher in all diabetic children than in nondiabetic controls. The activities of the antioxidant enzymes GPx, SOD, and CAT decreased significantly in diabetic children compared to in controls. Moreover, the activities of the enzymes tested were significantly reduced in the T1D-EV+ group compared to in the T1D-EV- group.. Our data indicate that EV infection correlated with a decrease in the activity of antioxidant enzymes in the T1D-EV+ group compared to in the T1D-EV- group; this may contribute to β cell damage and increased inflammation. Topics: Adolescent; Blood Glucose; C-Peptide; C-Reactive Protein; Catalase; Child; Child, Preschool; Diabetes Mellitus, Type 1; Enterovirus Infections; Female; Glutathione Peroxidase; Glycated Hemoglobin; Humans; Male; Superoxide Dismutase | 2018 |
The effects of metformin in type 1 diabetes mellitus.
This retrospective study investigated the effect of adding metformin to pharmacologic insulin dosing in type 1 diabetics on insulin therapy 1 year after treatment compared with patients on insulin therapy alone.. Twenty-nine adults with type 1 diabetes who had metformin added to their insulin therapy for 12 months were compared with 29 adults with type 1 diabetes who remained on insulin-alone therapy.. Fifty-eight patients with C peptide negative-type 1 diabetics (26 females, mean age: 29.01 ± 7.03 years, BMI: 24.18 ± 3.16 kg/m2) were analyzed. Age, sex, body weight, insulin dose requirement, plasma glucose (PG), blood pressure (BP), and lipids did not differ between groups before treatment (p > 0.05). Metabolic syndrome (44.8 vs 41.4%, p > 0.05) did not differ between the metformin-insulin and insulin alone groups before treatment. Metabolic syndrome was more decreased in the metformin-insulin group than in the insulin alone group after treatment (-8.9 ± 1.3 vs. 2.5 ± 0.6%, p = 0.028). Insulin dose requirement was lower in the metformin-insulin group than in the insulin alone group (-0.03 vs. 0.11 IU/kg/d, p = 0.006). Fasting PG (-26.9 ± 54.2 vs. 0.7 ± 29.5 mg/dL, p = 0.022) and postprandial PG (-43.1 ± 61.8 mg/dL vs. -3.1 ± 40.1 mg/dL, p = 0.010) was more decreased in the metformin-insulin group than in the insulin alone group. Body weight, lipids, and HbA1c did not differ between the groups (p > 0.05).. Metformin decreased glucose concentrations, reduced metabolic syndrome, as well as insulin dose requirement more than insulin therapy alone, 1 year after treatment. These results were independent of blood lipid improvement or weight loss, although on average weight remained decreased with metformin-insulin therapy, whereas the average weight increased with insulin therapy alone. Topics: Adult; Biomarkers; Blood Glucose; Body Weight; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Lipids; Male; Metabolic Syndrome; Metformin; Prognosis; Retrospective Studies | 2018 |
Protective effect of C-peptide on experimentally induced diabetic nephropathy and the possible link between C-peptide and nitric oxide.
Diabetic nephropathy one of the major microvascular diabetic complications. Besides hyperglycemia, other factors contribute to the development of diabetic complications as the proinsulin connecting peptide, C-peptide. We described the role of C-peptide replacement therapy on experimentally induced diabetic nephropathy, and its potential mechanisms of action by studying the role of nitric oxide (NO) as a mediator of C-peptide effects by in vivo modulating its production by N Topics: Angiotensin II; Animals; Biomarkers; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Enzyme Inhibitors; Islets of Langerhans; Kidney; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Proto-Oncogene Proteins c-bcl-2; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha | 2018 |
Impact of C-Peptide Status on the Response of Glucagon and Endogenous Glucose Production to Induced Hypoglycemia in T1DM.
Complete loss of β-cell function in patients with type 1 diabetes mellitus (T1DM) may lead to an increased risk of severe hypoglycemia.. We aimed to determine the impact of C-peptide status on glucagon response and endogenous glucose production (EGP) during hypoglycemia in patients with T1DM.. We conducted an open, comparative trial.. Ten C-peptide positive (C-pos) and 11 matched C-peptide negative (C-neg) patients with T1DM were enrolled.. Plasma glucose was normalized over the night fast, and after a steady-state (baseline) plateau all patients underwent a hyperinsulinemic, stepwise hypoglycemic clamp with glucose plateaus of 5.5, 3.5, and 2.5 mmol/L and a recovery phase of 4.0 mmol/L. Blood glucagon was measured with a specific and highly sensitive glucagon assay. EGP was determined with a stable isotope tracer technique.. Impact of C-peptide status on glucagon response and EGP during hypoglycemia.. Glucagon concentrations were significantly lower in C-pos and C-neg patients than previously reported. At baseline, C-pos patients had higher glucagon concentrations than C-neg patients (8.39 ± 4.6 vs 4.19 ± 2.4 pmol/L, P = 0.016, mean ± standard deviation) but comparable EGP rates (2.13 ± 0.2 vs 2.04 ± 0.3 mg/kg/min, P < 0.391). In both groups, insulin suppressed glucagon levels, but hypoglycemia revealed significantly higher glucagon concentrations in C-pos than in C-neg patients. EGP was significantly higher in C-pos patients at hypoglycemia (2.5 mmol/L) compared with C-neg patients.. Glucagon concentrations and EGP during hypoglycemia were more pronounced in C-pos than in C-neg patients, which indicates that preserved β-cell function may contribute to counterregulation during hypoglycemia in patients with T1DM. Topics: Adult; Awareness; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Epinephrine; Female; Glucagon; Glucose Clamp Technique; Humans; Hypoglycemia; Insulin; Male; Middle Aged; Norepinephrine; Young Adult | 2018 |
Role of adipose tissue derived stem cells differentiated into insulin producing cells in the treatment of type I diabetes mellitus.
Generation of new β cells is an important approach in the treatment of type 1 diabetes mellitus (type 1 DM). Adipose tissue-derived stem cells (ADSCs) might be one of the best sources for cell replacement therapy for diabetes. Therefore, this work aimed to test the possible role of transplanted insulin-producing cells (IPCs) differentiated from ADSCs in treatment of streptozotocin (STZ) induced type I DM in rats. Type 1 DM was induced by single intra peritoneal injection with STZ (50 mg/kg BW). Half of the diabetic rats were left without treatment and the other half were injected with differentiated IPCs directly into the pancreas. ADSCs were harvested, cultured and identified by testing their phenotypes through flow cytometry. They were further subjected to differentiation into IPCs using differentiation medium. mRNA expression of pancreatic transcription factors (pdx1), insulin and glucose transporter-2 genes by real time PCR was done to detect the cellular differentiation and confirmed by stimulated insulin secretion. The pancreatic tissues from all groups were examined 2 months after IPC transplantation and were subjected to histological, Immunohistochemical and morphometric study. The differentiated IPCs showed significant expression of pancreatic β cell markers and insulin secretion in glucose dependent manner. Treatment with IPCs induced apparent regeneration, diffused proliferated islet cells and significant increase in C-peptide immune reaction. We concluded that transplantation of differentiated IPCs improved function and morphology of Islet cells in diabetic rats. Consequently, this therapy option may be a promising therapeutic approach to patient with type 1 DM if proven to be effective and safe. Topics: Adipose Tissue; Animals; Blood Glucose; C-Peptide; Cell Differentiation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucose Transporter Type 2; Homeodomain Proteins; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Protein Domains; Rats; Stem Cells; Trans-Activators | 2018 |
Intrinsic insulin secretion capacity might be preserved by discontinuing anti-programmed cell death protein 1 antibody treatment in 'anti-programmed cell death protein 1 antibody-induced' fulminant type 1 diabetes.
Intrinsic insulin secretion capacity may be preserved by discontinuing anti-PD-1 antibody treatment in 'anti-PD-1 antibody-induced'fulminant type 1 diabetes. Topics: Adult; Antibodies, Monoclonal; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Immunotherapy; Insulin; Insulin Secretion; Melanoma; Nivolumab; Programmed Cell Death 1 Receptor | 2018 |
Immune cell and cytokine patterns in children with type 1 diabetes mellitus undergoing a remission phase: A longitudinal study.
Type 1 diabetes (T1D) develops in distinct stages, before and after disease onset. Whether the natural course translates into different immunologic patterns is still uncertain. This study aimed at identifying peripheral immune patterns at key time-points, in T1D children undergoing remission phase.. Children with new-onset T1D and healthy age and gender-matched controls were recruited at a pediatric hospital. Peripheral blood samples were evaluated by flow cytometry at 3 longitudinal time-points: onset (T1), remission phase (T2) and established disease (T3). Cytokine levels were quantified by multiplex assay. Fasting C-peptide, HbA1c, and 25OHD were also measured.. T1D children (n = 28; 10.0 ± 2.6 years) showed significant differences from controls in circulating neutrophils, T helper (Th)17 and natural killer (NK) cells, with relevant variations during disease progression. At onset, neutrophils, NK, Th17 and T cytotoxic (Tc)17 cells were decreased. As disease progressed, neutrophil counts recovered whereas NK counts remained low. Th17 and Tc17 cells behavior followed the neutrophil variation pattern. B-cells were lowest in the remission phase and regulatory T-cells significantly declined after remission. Two cytokine response profiles were identified. Low cytokine-responders showed higher circulating fasting C-peptide levels at onset and longer remission periods. C-peptide inversely correlated with pro-inflammatory and cytotoxic cells.. Our data suggest an association between immune cells, cytokine patterns and metabolic counterparts. The dynamic changes of circulating immune cells during disease progression involve key innate and acquired immune cell types. This longitudinal picture of T1D progression may enable disease staging and patient stratification, essential for individualized treatment. Topics: Adolescent; C-Peptide; Case-Control Studies; Child; Cytokines; Diabetes Mellitus, Type 1; Disease Progression; Female; Humans; Leukocyte Count; Longitudinal Studies; Male | 2018 |
The Potential Role of PTPN-22 C1858T Gene Polymorphism in the Pathogenesis of Type 1 Diabetes in Saudi Population.
Recent investigations have reported an association between protein tyrosine phosphatase non-receptor type-22 (PTPN-22) gene polymorphism and susceptibility to the development of type 1 diabetes (T1D) in some populations and not in others. In this study, we aimed to investigate the association of PTPN-22 C1858T polymorphism with T1D in Saudi children.. A cohort of 372 type 1 diabetic children and 372 diabetes-free subjects was enrolled in the current investigation. The PTPN-22 C1858T polymorphism was identified using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.. Our data showed that the frequency of CT and TT genotypes of PTPN-22 C1858T was higher in T1D children (17.7% and 4.3%, respectively) compared to healthy controls (4.8% and 1.6%, respectively), and both genotypes were statistically associated with T1D patients (OR = 4.4, 95% CI: 2.55-7.58, p < 0.001; and OR = 3.2, 95% CI: 1.23-8.28, p = 0.017, respectively). Moreover, the 1858T allele was significantly associated with T1D patients compared to the C allele (OR = 3.2, 95% CI: 1.59-6.88, p < 0.001). In addition, the T allele was significantly associated with elevated levels of HbA1c, anti-GAD, and anti-insulin antibodies (p < 0.001) and a lower concentration of C-peptide (p < 0.001) in T1D children.. The data presented here suggests that the T allele of PTPN-22 C1858T polymorphism might be a risk factor for T1D development in Saudi children. Topics: Alleles; Biomarkers; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Glycated Hemoglobin; Humans; Logistic Models; Male; Odds Ratio; Polymorphism, Single Nucleotide; Protein Tyrosine Phosphatase, Non-Receptor Type 22; Risk Factors; Saudi Arabia | 2018 |
Factors associated with preservation of C-peptide levels at the diagnosis of type 1 diabetes.
The level of C-peptide can identify individuals most likely to respond to immune interventions carried out to prevent pancreatic β-cell damage. The aim of the study was to evaluate factors associated with C-peptide levels at type 1 diabetes (T1D) diagnosis.. This study included 1098 children aged 2-17 with newly recognized T1D. Data were collected from seven Polish hospitals. The following variables were analyzed: date of birth, fasting C-peptide, HbA1c, sex, weight, height, pH at diabetes onset.. A correlation was observed between fasting C-peptide level and BMI-SDS (p = 0.0001), age (p = 0.0001), and HbA1c (p = 0.0001). The logistic regression model revealed that fasting C-peptide ≥0.7 ng/ml at diabetes diagnosis was dependent on weight, HbA1c, pH and sex (p < 0.0001). Overweight and obese children (n = 124) had higher fasting C-peptide (p = 0.0001) and lower HbA1c (p = 0.0008) levels than other subjects. Girls had higher fasting C-peptide (p = 0.036) and higher HbA1c (p = 0.026) levels than boys.. Obese and overweight children are diagnosed with diabetes at an early stage with largely preserved C-peptide levels. Increased awareness of T1D symptoms as well as improved screening and diagnostic tools are important to preserve C-peptide levels. There are noticeable gender differences in the course of diabetes already at T1D diagnosis. Topics: Adolescent; Age of Onset; Blood Glucose; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Early Diagnosis; Fasting; Female; Glycated Hemoglobin; Humans; Male; Pediatric Obesity; Poland; Risk Factors; Time Factors | 2018 |
Higher Cord Blood Levels of Fatty Acids in Pregnant Women With Type 1 Diabetes Mellitus.
Type 1 diabetes mellitus (T1DM) is associated with a disturbance of carbohydrate and lipid metabolism.. To determine whether T1DM alters maternal and neonatal fatty acid (FA) levels.. Observational study.. Academic hospital.. Sixty pregnant women (30 women with T1DM with good glycemic control and 30 healthy women) were included in the study. Maternal blood, umbilical vein, and artery blood samples were collected immediately upon delivery. Following lipid extraction, the FA profiles of the total FA pool of maternal serum and umbilical vein and artery serum were determined by gas chromatography.. Total FA concentration in maternal serum did not differ between the study groups; it was significantly higher in umbilical vein serum of the T1DM group compared with that in the control group [median (interquartile range)]: T1DM 2126.2 (1446.4 to 3181.3) and control 1073.8 (657.5 to 2226.0; P < 0.001), and in umbilical artery vein serum: T1DM 1805.7 (1393.1 to 2125.0) and control 990.0 (643.3 to 1668.0; P < 0.001). Composition of FAs in umbilical vein serum showed significantly higher concentrations of saturated, monounsaturated, and polyunsaturated FAs (SFAs, MUFAs, and PUFAs, respectively) in the T1DM group than compared with those in the control group (P = 0.001). Furthermore, cord blood levels of leptin (P < 0.001), C-peptide (P < 0.001), and insulin resistance (P = 0.015) were higher in the T1DM group compared with controls.. The neonates born to mothers with T1DM had higher concentrations of total FAs, SFAs and MUFAs, as well as PUFAs, compared with control newborns. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids; Fatty Acids, Monounsaturated; Fatty Acids, Unsaturated; Female; Fetal Blood; Humans; Infant, Newborn; Insulin Resistance; Leptin; Pregnancy; Pregnancy in Diabetics; Umbilical Arteries; Umbilical Veins; Young Adult | 2018 |
Short-term changes in pancreatic α-cell function after the onset of fulminant type 1 diabetes.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucagon-Secreting Cells; Humans | 2018 |
Fulminant Type 1 Diabetes Mellitus Presenting 15 Days after Delivery Diagnosed in Cooperation with Obstetricians.
The patient was a 32-year-old Japanese woman who was given a 75-g oral glucose tolerance test at the 35th week of pregnancy and was normoglycemic. She had excessive thirst and polyuria from 15 days after delivery. When she visited for the 1-month postpartum checkup, her plasma glucose level was 479 mg/dL, HbA1c was 7.4%, and urinary C-peptide was 1.1 μg/mL; she was therefore diagnosed with fulminant type 1 diabetes mellitus associated with pregnancy. All physicians should be aware of this disease so as to provide a prompt diagnosis and emergency treatment and consequently improve the maternal prognosis. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Puerperal Disorders | 2018 |
C-PEPTIDE AND BETA-CELL AUTOANTIBODY TESTING PRIOR TO INITIATING CONTINUOUS SUBCUTANEOUS INSULIN INFUSION PUMP THERAPY DID NOT IMPROVE UTILIZATION OR MEDICAL COSTS AMONG OLDER ADULTS WITH DIABETES MELLITUS.
To study the impact of the C-peptide and beta-cell autoantibody testing required by the Center for Medicare and Medicaid Services (CMS) on costs/utilization for patients with diabetes mellitus initiating continuous subcutaneous insulin infusion (CSII) therapy.. This retrospective study used propensity score-matched patients. Analysis 1 compared patients 1-year pre- and 2-years post-CSII adoption who met or did not meet CMS criteria. Analysis 2 compared Medicare Advantage patients using CSII or multiple daily injections (MDI) who did not meet CMS criteria for 1-year pre- and 1-year post-CSII adoption. Analysis 3 extended analysis 2 to 2 years postindex and also included a subset of patients ≥55 years old but not yet in Medicare Advantage.. Analysis 1 resulted in significantly slower growth in hospital admissions ( P = .0453) in CSII-treated patients who did not meet the criteria. Analyses 2 and 3 showed numerically slower growth in inpatient, outpatient, and emergency department (ED) costs for CSII versus MDI patients (both not meeting criteria). Analysis 3 showed significantly slower growth in ED costs and hospital admissions for CSII versus MDI Medicare Advantage patients before propensity matching (both P<.05). In patients ≥55 years old, ED costs grew more slowly for CSII than MDI therapy ( P = .0678).. Numerically slower growth in hospital admissions was seen for pump adopters who did not meet CMS C-peptide criteria, while medical costs growth was similar. For CSII users who did not meet the CMS criteria, numerically slower growth in inpatient, outpatient, ED costs, and hospital admissions occurred versus MDI.. CMS = Center for Medicare and Medicaid Services; CSII = continuous subcutaneous insulin infusion; DM = diabetes mellitus; DME = durable medical equipment; ED = emergency department; MDI = multiple daily injections (of insulin). Topics: Aged; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Insulin Infusion Systems; Middle Aged; Retrospective Studies | 2018 |
Frequent Monitoring of C-Peptide Levels in Newly Diagnosed Type 1 Subjects Using Dried Blood Spots Collected at Home.
To evaluate an approach to measure β-cell function by frequent testing of C-peptide concentrations in dried blood spots (DBSs).. Thirty-two children, aged 7 to 17 years, with a recent diagnosis of type 1 diabetes.. Mixed-meal tolerance test (MMTT) within 6 and again at 12 months after diagnosis, with paired venous and DBS C-peptide sampling at 0 and 90 minutes. Weekly DBS C-peptide before and after standardized breakfasts collected at home.. DBS and plasma C-peptide levels (n = 115) correlated strongly (r = 0·91; P < 0.001). The Bland-Altman plot indicated good agreement. The median number of home-collected DBS cards per participant was 24 over a median of 6.9 months. Repeated DBS C-peptide levels varied considerably within and between subjects. Adjustment for corresponding home glucose measurements reduced the variance, permitting accurate description of changes over time. The correlation of the C-peptide slope over time (assessed by repeated home DBS) vs area under the curve during the two MMTTs was r = 0.73 (P < 0.001). Mixed models showed that a 1-month increase in diabetes duration was associated with 17-pmol/L decline in fasting DBS C-peptide, whereas increases of 1 mmol/L in glucose, 1 year older age at diagnosis, and 100 pmol/L higher baseline plasma C-peptide were associated with 18, 17, and 61 pmol/L higher fasting DBS C-peptide levels, respectively. In addition, glucose responsiveness decreased with longer diabetes duration.. Our approach permitted frequent assessment of C-peptide, making it feasible to monitor β-cell function at home. Evaluation of changes in the slope of C-peptide through this method may permit short-term evaluation of promising interventions. Topics: Adolescent; Area Under Curve; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Correlation of Data; Diabetes Mellitus, Type 1; Dried Blood Spot Testing; Fasting; Feasibility Studies; Female; Humans; Male; Time Factors | 2018 |
Associations of serum glucagon levels with glycemic variability in type 1 diabetes with different disease durations.
Glucagon has been recognized as a pivotal factor implicated in the pathophysiology ofdiabetes. The purpose of this study is to investigate the dynamic secretion levels of serum glucagon (GLA) in patients with type 1 diabetes mellitus (T1DM) with different courses of disease, and to analyze its correlation with blood glucose fluctuation.. This observational study included 55 T1DM patients and divided into 3 groups according to the courses of disease. Group 1(the disease duration <1 year), Group 2(1≤the disease durations≤5), 3(the disease durations >5 years). All patients underwent a 100g standard steamed buns meal test,measuring the levels of serum glucose, glucagon, insulin, C-peptide in different points of time, and 48 of the total patients used continuous glucose monitoring system (CGMS) to monitor blood glucose.. The fasting glucagon level in Group 1 was significantly higher than it in Group 2. Furthermore, the GLA1h, the GLA3h and the AUCGLA0-3h in Group 1 were greatly larger than those in Group 3. Referring to glycemic variability, the LBGI, AUC of hypoglycemia, the percentage of hypoglycemia time andthe times of nocturnal hypoglycemia in Group 1 were significantly lower than those in Group 3. Moreover,the fasting glucagon level was the independent factors to SD and MAGE. The AUCGLA0-3h were negatively correlated with MODD, LBGI, GRADE-hypo and AUC of nocturnal hypoglycemia.. It is concluded that glucagon secretory function impairs with duration of type 1 diabetes extended and correlates to glycemic fluctuation, especially hypoglycemia. Topics: Adolescent; Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Humans; Insulin; Male; Middle Aged; Time Factors; Young Adult | 2018 |
Exploring C-peptide loss in type 1 diabetes using growth curve analysis.
C-peptide (CP) loss in type 1 diabetes (T1D) is highly variable, and factors influencing it are poorly understood. We modelled CP values in T1D patients from diagnosis for up to 6 years, treating the serial data as growth curves plotted against time since diagnosis. The aims were to summarise the pattern of CP loss (i.e. growth curve shape) in individual patients in simple terms, and to identify baseline characteristics that predict this pattern in individuals.. Between 1976 and 2011, 442 T1D patients initially aged <18y underwent 120-minute mixed meal tolerance tests (MMTT) to calculate area under the curve (AUC) CP, at 3, 9, 18, 30, 48 and 72 months after diagnosis (n = 1537). The data were analysed using the novel SITAR mixed effects growth curve model (SuperImposition by Translation And Rotation). It fits a mean AUC growth curve, but also allows the curve's mean level and rate of fall to vary between individuals so as to best fit the individual patient curves. These curve adjustments define individual curve shape.. The square root (√) AUC scale provided the best fit. The mean levels and rates of fall for individuals were normally distributed and uncorrelated with each other. Age at diagnosis and √AUC at 3 months strongly predicted the patient-specific mean levels, while younger age at diagnosis (p<0.0001) and the 120-minute CP value of the 3-month MMTT (p = 0.002) predicted the patient-specific rates of fall.. SITAR growth curve analysis is a useful tool to assess CP loss in type 1 diabetes, explaining patient differences in terms of their mean level and rate of fall. A definition of rapid CP loss could be based on a quantile of the rate of fall distribution, allowing better understanding of factors determining CP loss and stratification of patients into targeted therapies. Topics: Adolescent; Area Under Curve; Biomarkers; C-Peptide; Cell Count; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin-Secreting Cells; Male | 2018 |
CD4 T Cells Reactive to Hybrid Insulin Peptides Are Indicators of Disease Activity in the NOD Mouse.
We recently established that hybrid insulin peptides (HIPs), formed in islet β-cells by fusion of insulin C-peptide fragments to peptides of chromogranin A or islet amyloid polypeptide, are ligands for diabetogenic CD4 T-cell clones. The goal of this study was to investigate whether HIP-reactive T cells were indicative of ongoing autoimmunity. MHC class II tetramers were used to investigate the presence, phenotype, and function of HIP-reactive and insulin-reactive T cells in NOD mice. Insulin-reactive T cells encounter their antigen early in disease, but they express FoxP3 and therefore may contribute to immune regulation. In contrast, HIP-reactive T cells are proinflammatory and highly diabetogenic in an adoptive transfer model. Because the frequency of antigen-experienced HIP-reactive T cells increases over progression of disease, they may serve as biomarkers of autoimmune diabetes. Topics: Animals; Autoantigens; Autoimmune Diseases; Autoimmunity; Biomarkers; C-Peptide; CD4-Positive T-Lymphocytes; Cells, Cultured; Chromogranin A; Clone Cells; Crosses, Genetic; Diabetes Mellitus, Type 1; Disease Progression; Female; Islet Amyloid Polypeptide; Lymphocyte Activation; Mice, Inbred NOD; Mice, Knockout; Mice, SCID; Peptide Fragments; Recombination, Genetic; Specific Pathogen-Free Organisms | 2018 |
Serum Vitamin D and Its Upregulated Protein, Thioredoxin Interacting Protein, Are Associated With Beta-Cell Dysfunction in Adult Patients With Type 1 and Type 2 Diabetes.
Diabetes mellitus is characterized by either complete deficiency of insulin secretion, as in type 1 diabetes, or decompensation of the pancreatic beta cells in type 2 diabetes. Both vitamin D (vitD) and thioredoxin interacting protein (TXNIP) have been shown to be involved in beta-cell dysfunction. Therefore, this study was designed to examine vitD and TXNIP serum levels in patients with diabetes and to correlate these levels with beta-cell function markers in both types of diabetes.. The routine biochemical parameters and the serum levels of vitD and TXNIP were measured in 20 patients with type 1 diabetes and 20 patients with type 2 diabetes. The levels were then compared to those of 15 healthy control volunteers. Insulin, C-peptide and proinsulin (PI), vitD and TXNIP were measured by ELISA. Beta-cell dysfunction was assessed by homeostatic model assessment (HOMA-beta), proinsulin-to-C-peptide (PI/C) and proinsulin-to-insulin (PI/I) ratios. Correlations among various parameters were studied.. Patients with type 1 diabetes had significantly lower HOMA-beta, vitD and TXNIP levels; however, they had higher PI/C levels than the control group. Meanwhile, patients with type 2 diabetes had significantly higher C-peptide, proinsulin, PI/C, HOMA-insulin resistance (HOMA-IR) and lower HOMA-beta and vitD levels, with no significant difference in TXNIP levels as compared to the control group. In addition, vitD was significantly correlated positively with HOMA-beta and TXNIP and negatively with PI, PI/C, PI/I and HOMA-IR. TXNIP correlated positively with HOMA-beta and negatively with PI/C.. Our data showed that vitD and TXNIP were associated with different beta-cell dysfunction markers, indicating their potential abilities to predict the beta-cell status in people with diabetes. Topics: C-Peptide; Carrier Proteins; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Homeostasis; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Pancreatic Diseases; Proinsulin; Vitamin D | 2018 |
Does Islet Size Really Influence Graft Function After Clinical Islet Transplantation?
It has been proposed that islet transplants comprised primarily of small rather than large islets may provide better graft function, due to their lower susceptibility to hypoxic damage. Our aim was to determine whether islet size correlated with in vivo graft function in islet transplant recipients with C peptide-negative type 1 diabetes when islets have undergone pretransplant islet culture.. Human pancreatic islets were isolated, cultured for 24 hours and infused by standardized protocols. Ninety-minute stimulated C-peptide concentrations were determined during a standard meal tolerance test 3 months posttransplant. The islet isolation index (IEq/islet number) was determined immediately after isolation and again before transplantation (after tissue culture). This was correlated with patient insulin requirement or stimulated C-peptide.. Changes in insulin requirement did not significantly correlate with islet isolation index. Stimulated C-peptide correlated weakly with IEq at isolation (P = 0.40) and significantly with IEq at transplantation (P = 0.018). Stimulated C-peptide correlated with islet number at isolation (P = 0.013) and more strongly with the islet number at transplantation (P = 0.001). In contrast, the correlation of stimulated C-peptide and islet isolation index was weaker (P = 0.018), and this was poorer at transplantation (P = 0.034). Using linear regression, the strongest association with graft function was islet number (r = 0.722, P = 0.001). Islet size was not related to graft function after adjusting for islet volume or number.. These data show no clear correlation between islet isolation index and graft function; both small and large islets are suitable for transplantation, provided the islets have survived a short culture period postisolation. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Graft Survival; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Time Factors; Tissue Culture Techniques; Treatment Outcome | 2018 |
β Cell dysfunction exists more than 5 years before type 1 diabetes diagnosis.
The duration and patterns of β cell dysfunction during type 1 diabetes (T1D) development have not been fully defined.. Metabolic measures derived from oral glucose tolerance tests (OGTTs) were compared between autoantibody-positive (aAb+) individuals followed in the TrialNet Pathway to Prevention study who developed diabetes after 5 or more years or less than 5 years of longitudinal follow-up (Progressors≥5, n = 75; Progressors<5, n = 474) and 144 aAb-negative (aAb-) relatives.. Mean age at study entry was 15.0 ± 12.6 years for Progressors≥5; 12.0 ± 9.1 for Progressors<5; and 16.3 ± 10.4 for aAb- relatives. At baseline, Progressors≥5 already exhibited significantly lower fasting C-peptide (P < 0.01), C-peptide AUC (P < 0.001), and early C-peptide responses (30- to 0-minute C-peptide; P < 0.001) compared with aAb- relatives, while 2-hour glucose (P = 0.03), glucose AUC (<0.001), and Index60 (<0.001) were all higher. Despite significant baseline impairment, metabolic measures in Progressors≥5 were relatively stable until 2 years prior to T1D diagnosis, when there was accelerated C-peptide decline and rising glycemia from 2 years until diabetes diagnosis. Remarkably, patterns of progression within 3 years of diagnosis were nearly identical between Progressors≥5 and Progressors<5.. These data provide insight into the chronicity of β cell dysfunction in T1D and indicate that β cell dysfunction may precede diabetes diagnosis by more than 5 years in a subset of aAb+ individuals. Even among individuals with varying lengths of aAb positivity, our findings indicate that patterns of metabolic decline are uniform within the last 3 years of progression to T1D.. Clinicaltrials.gov NCT00097292.. The Type 1 Diabetes TrialNet Study Group is a clinical trials network currently funded by the NIH through the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Allergy and Infectious Diseases, and The Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Juvenile Diabetes Research Foundation. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Fasting; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin-Secreting Cells; Longitudinal Studies; Male; Prospective Studies; Time Factors; Young Adult | 2018 |
Factors Influencing Frequency and Duration of Remission in Children and Adolescents Newly Diagnosed with Type 1 Diabetes.
BACKGROUND This study aimed to determine the frequency and duration of remission in children and adolescents newly diagnosed with type 1 diabetes and to investigate factors associated with these parameters. MATERIAL AND METHODS Fifty patients newly diagnosed with T1DM were followed for 1 year. Daily insulin requirement of less than 0.5 U/kg/day dose when the HbA1c value is less than 8% was regarded as partial remission. Patients were grouped according to their remission duration. Clinical and laboratory characteristics of the remission groups and non-remission groups were compared to find factors influencing remission and to investigate their contribution to the duration of remission. RESULTS Remission was observed in 24 (48%) out of 50 patients included in the study. Remission frequency was found to be associated with age, sex, and puberty. Longer duration of remission was more frequent in the younger age group, in pre-pubertal stage, and in male patients. Daily insulin dose and basal insulin requirement of those who went into remission was found to be significantly lower than in the other patients at discharge. CONCLUSIONS Decreased daily total and basal insulin requirement at discharge are valuable in predicting remission. The remission process in type 1 diabetes still has many characteristics that need to be clarified. Therefore, more extensive studies are needed. Topics: Adolescent; Age Factors; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease-Free Survival; Female; Glycated Hemoglobin; Humans; Insulin; Male; Remission Induction; Remission, Spontaneous; Sex Factors; Sexual Maturation; Time Factors | 2018 |
Cognitive Function Is Impaired in Patients with Recently Diagnosed Type 2 Diabetes, but Not Type 1 Diabetes.
To test whether cognitive function is impaired in early states of diabetes and to identify possible risk factors for cognitive impairment.. A cross-sectional analysis within the German Diabetes Study included patients with type 1 or type 2 diabetes within the first year after diagnosis or five years after study inclusion and metabolically healthy individuals. Participants underwent comprehensive metabolic phenotyping and testing of different domains of cognitive function. Linear regression models were used to compare cognition test outcomes and to test associations between cognitive function and possible influencing factors within the groups.. In participants with recently diagnosed diabetes, verbal memory was poorer in patients with type 2 diabetes (. Verbal memory is impaired in individuals with recently diagnosed type 2 diabetes and likely associated with higher body mass. This trial is registered with the trial registration number NCT01055093. Topics: Adult; Aged; Biomarkers; Blood Glucose; Body Mass Index; C-Peptide; Cognition; Cognition Disorders; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Germany; Glycated Hemoglobin; Humans; Intelligence; Male; Memory; Middle Aged; Obesity; Prognosis; Prospective Studies; Risk Factors; Sex Factors; Time Factors; Verbal Behavior | 2018 |
Epidemiology of childhood-onset type 1 diabetes in Azerbaijan: Incidence, clinical features, biochemistry, and HLA-DRB1 status.
Determine the incidence and typology of diabetes in children in Azerbaijan.. Clinical features, C-peptide, autoantibodies (glutamic acid decarboxylase 65 (GAD65) and islet antigen 2 (IA-2)), and HLA-DRB1 status were studied in 106 subjects <18 years of age who were recently diagnosed. 104 cases were consecutive. Incidence was determined for Baku and Absheron regions, where ascertainment is estimated to be essentially 100%.. 104 of the 106 (98%) were diagnosed with type 1 diabetes, one with type 2 diabetes and one with atypical diabetes. Type 1 diabetes incidence in Baku City and Absheron was 7.05 per 100,000 population <15 years per year. Peak age of onset was 10 years. There was a slight male preponderance (male:female 1.17:1), and no temporal association with seasons. Almost all type 1 diabetes subjects presented with classic symptoms including a high incidence (58%) of diabetic ketoacidosis. 86% presented with low C-peptide values (<0.13 nmol/L, <0.40 ng/mL) and 74% were positive for at least one type 1 diabetes-related autoantibody.. Azerbaijan has a moderate type 1 diabetes incidence and clinical, biochemical and genetic features similar to that in European populations. Topics: Adolescent; Autoantibodies; Azerbaijan; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA-DRB1 Chains; Humans; Incidence; Infant; Male | 2018 |
Temporal dynamics of serum let-7g expression mirror the decline of residual beta-cell function in longitudinal observation of children with type 1 diabetes.
In type 1 diabetes mellitus (T1DM), the introduction of insulin is typically followed by a brief remission period, with subsequent gradual decline in beta-cell function. Several studies described altered profile of circulating miRNAs (microRNAs) in T1DM patients and proposed them as biomarkers of associated pathologic processes.. Serum miRNA expression profile reflects residual beta-cell function and autoimmunity in T1DM.. The profiling group included patients with: GCK-MODY (N = 13), T1DM (N = 9), and 10 healthy controls. The longitudinal group included 34 patients with samples collected at diagnosis of T1DM and first, third, and fourth to eighth year since diagnosis.. We reanalyzed data from the profiling group for miRNAs differentially expressed between patients with T1DM, other types of diabetes and controls. Afterward, we shortlisted miRNAs on the basis of this reanalysis and literature review and quantified their expression with quantitative polymerase chain reaction. Additionally, we measured the levels of anti-islet antibodies (islet cell antibodies, glutamic acid decarboxylase antibodies, IA2 antibodies, and ZnT8A) and C-peptide concentrations across the four timepoints in the longitudinal group.. miR-24 and let-7g serum expression differed significantly between GCK-MODY, controls, and HbA1c-matched T1DM patients; P < 0.05, false discovery rate < 0.05. Autoantibodies levels showed decreasing linear trend in repeated timepoints (all P < 0.0001). C-peptide concentration peaked during the first year after diagnosis, corresponding to remission phase, and declined in consecutive measurements. This dynamic was evidenced for let-7g expression levels (P = 0.0058).. The pattern of let-7g expression change during the course of diabetes mirrors that of C-peptide levels, hinting at this microRNA's association with the residual mass of the beta cells in patients with T1DM. Topics: Adolescent; Autoantibodies; Autoimmunity; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Humans; Infant; Insulin-Secreting Cells; Longitudinal Studies; Male; MicroRNAs; Prognosis; Time Factors; Transcriptome | 2018 |
Proinsulin C-peptide is an autoantigen in people with type 1 diabetes.
Type 1 diabetes (T1D) is an autoimmune disease in which insulin-producing beta cells, found within the islets of Langerhans in the pancreas, are destroyed by islet-infiltrating T cells. Identifying the antigenic targets of beta-cell reactive T cells is critical to gain insight into the pathogenesis of T1D and develop antigen-specific immunotherapies. Several lines of evidence indicate that insulin is an important target of T cells in T1D. Because many human islet-infiltrating CD4 Topics: Adolescent; Adult; Autoantigens; C-Peptide; CD4-Positive T-Lymphocytes; Cells, Cultured; Child; Child, Preschool; Diabetes Mellitus, Type 1; HLA Antigens; Humans; Islets of Langerhans; Middle Aged; Proinsulin; Young Adult | 2018 |
Comparison of proinsulin and C-peptide secretion in healthy versus long-standing type 1 diabetes mellitus cohorts: A pilot study.
Increased proinsulin (PI) compared to C-peptide (CP) concentrations have been reported, both prior to type 1 diabetes mellitus (T1D) onset, as well as early in disease. In this pilot study, we sought to define the normal PI secretion in a healthy cohort and compare this to a local T1D cohort and a separate well-defined nationally representative T1D cohort with measurable CP.. Thirteen healthy subjects and 12 T1D subjects with T1D >3 years from the local T1D cohort completed mixed meal tolerance tests (MMTT) with PI and CP measured over 90 and 240 minutes. The change in CP (maximum versus baseline, ΔCP) during MMTT in the T1D Exchange T1D cohort was stratified according to non-fasting PI concentrations, based on a fasting PI threshold, as defined by the healthy control group.. The maximum fasting PI in the control group was 6 pmol/L. Individuals from the T1D Exchange with a non-fasting PI ≥ 6 pmol/L had a lower ΔCP during a MMTT, compared to those with a PI < 6 pmol/L. While only three individuals from the local T1D cohort had measurable CP and PI during the MMTT, those with a greater ΔCP had lower PI secretion.. While all T1D subjects from the T1D Exchange secreted measurable non-fasting PI, those with a greater non-fasting PI demonstrated a decrease in ΔCP during the MMTT. PI may be preferentially secreted compared to CP in some individuals with long standing T1D. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Case-Control Studies; Cohort Studies; Diabetes Mellitus, Type 1; Female; Humans; Male; Middle Aged; Pilot Projects; Proinsulin; Young Adult | 2018 |
[Protective effect of vitamin A on residual pancreatic β cell function in children with type 1 diabetes mellitus].
To study the protective effect of vitamin A on residual pancreatic β cell function in children with type 1 diabetes mellitus (T1DM) and its mechanism.. A total of 46 children with T1DM (with a course of disease of 0.5-1 year) were randomly divided into an intervention group and a non-intervention group (n=23 each). The children in both groups were given insulin treatment, and those in the intervention group were also given vitamin A at a daily dose of 1 500-2 000 IU. A total of 25 healthy children were enrolled as the control group. The daily dose of insulin was calculated for the children with T1DM, and the serum levels of glycosylated hemoglobin (HbA1C), stimulated C-peptide, vitamin A, and interleukin-17 (IL-17) were measured before intervention and 3 months after intervention.. Before vitamin A intervention, the intervention group and the non-intervention group had a significantly lower serum level of vitamin A and a significantly higher level of IL-17 than the control group (P<0.01). After 3 months of intervention, the intervention group had significantly lower serum IL-17 level and insulin dose and a significantly higher level of stimulated C-peptide than the non-intervention group (P<0.05).. Vitamin A may protect residual pancreatic β cell function, possibly by improving the abnormal secretion of IL-17 in children with T1DM. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Infant; Insulin; Insulin-Secreting Cells; Vitamin A | 2018 |
Characterization of diabetes following pancreatic surgery in patients with congenital hyperinsulinism.
Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycaemia in infancy that leads to unfavourable neurological outcome if not treated adequately. In patients with severe diffuse CHI it remains under discussion whether pancreatic surgery should be performed or intensive medical treatment with the acceptance of recurrent episodes of mild hypoglycaemia is justified. Near-total pancreatectomy is associated with high rates of insulin-dependent diabetes mellitus and exocrine pancreatic insufficiency. Little is known about the management and long-term glycaemic control of CHI patients with diabetes after pancreatic surgery. We searched the German/Austrian DPV database and compared the course of 42 CHI patients with diabetes to that of patients with type 1 diabetes mellitus (T1DM). Study groups were compared at diabetes onset and after a follow-up period of 6.1 [3.3-9.7] (median [interquartile range]) years.. The majority of CHI patients with diabetes were treated with insulin (85.2% [70.9-99.5] at diabetes onset, and 90.5% [81.2-99.7] at follow-up). However, compared to patients with T1DM, significantly more patients in the CHI group with diabetes were treated with conventional insulin therapy (47.8% vs. 24.4%, p = 0.03 at diabetes onset, and 21.1% vs. 6.4% at follow-up, p = 0.003), and only a small number of CHI patients were treated with insulin pumps. Daily insulin dose was significantly lower in CHI patients with diabetes than in patients with T1DM, both at diabetes onset (0.3 [0.2-0.5] vs. 0.6 IE/kg/d [0.4-0.8], p = 0.003) and follow-up (0.8 [0.4-1.0] vs. 0.9 [0.7-1.0] IE/kg/d, p = 0.02), while daily carbohydrate intake was comparable in both groups. Within the first treatment year, HbA1c levels were significantly lower in CHI patients with diabetes (6.2% [5.5-7.9] vs. 7.2% [6.5-8.2], p = 0.003), but increased to a level comparable to that of T1DM patients at follow-up. Interestingly, in CHI patients, the risk of severe hypoglycaemia tends to be higher only at diabetes onset (14.8% vs. 5.8%, p = 0.1).. In surgically treated CHI patients insulin treatment needs to be intensified in order to achieve good glycaemic control. Our data furthermore emphasize the need for improved medical treatment options for patients with diazoxide- and/or octreotide-unresponsive CHI. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Congenital Hyperinsulinism; Diabetes Mellitus, Type 1; Diazoxide; Female; Humans; Hypoglycemia; Insulin; Male; Octreotide; Pancreas; Pancreatectomy | 2018 |
The characteristics of blood glucose fluctuations in patients with fulminant type 1 diabetes mellitus in the stable stage.
The aim was to characterize blood glucose fluctuations in patients with fulminant type 1 diabetes (FT1DM) at the stable stage using continuous blood glucose monitoring systems (CGMSs).. Ten patients with FT1DM and 20 patients with classic type 1 diabetes mellitus (T1DM) (the control group) were monitored using CGMSs for 72 hours.. The CGMS data showed that the mean blood glucose (MBG), the standard deviation of the blood glucose (SDBG), the mean amplitude glycemic excursions (MAGE), the blood glucose areas and the percentages of blood glucose levels below 13.9 mmol/L were similar between the two groups. However, the percentage of blood glucose levels below 3.9 mmol/L was significantly higher in the FT1DM group compared to the T1DM group (p < 0.05). The minimum (Min) blood glucose level in the FT1DM group was significantly lower than that of the T1DM group (p < 0.05). Patients with FT1DM had severe dysfunction of the islet beta cells and alpha cells compared to patients with T1DM, as indicated by lower C-peptide values and higher glucagon/C-peptide values.. In conclusion, patients with FT1DM at the stable stage were more prone to hypoglycemic episodes as recorded by CGMSs, and they had a greater association with severe dysfunction of both the beta and alpha islet cells compared to patients with T1DM. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Reference Values; Retrospective Studies; Statistics, Nonparametric | 2018 |
Effects of encapsulated porcine islets on glucose and C-peptide concentrations in diabetic nude mice 6 months after intraperitoneal transplantation.
In patients with type 1 diabetes, allogeneic islet transplantation can provide normal HbA1c concentrations, but it requires immunosuppression. Transplanting encapsulated islets into the peritoneal cavity could reduce or eliminate the need for immunosuppression. One of the uncertain features of intraperitoneal islet transplantation is the difficulty of measuring C-peptide concentrations in peripheral blood, which is often used for the marker of islet function. We hypothesized that secreted C-peptide from intraperitoneally transplanted islets was mostly consumed in the peritoneal cavity, which resulted in low C-peptide concentrations in peripheral blood.. In each of two experiments, encapsulated neonatal porcine islets were intraperitoneally transplanted into four nude mice with streptozotocin-induced diabetes. Three diabetic nude mice without transplanted islets were used as diabetic controls, and three untreated healthy nude mice were used as normal controls. Islet functions were monitored for 2 months in the first experiment and 6 months in the second experiment. Encapsulated islets were retrieved after each experiment and evaluated by fluorescein diacetate/propidium iodide tests for the viability and static glucose-stimulated insulin release tests for the function. C-peptide concentrations from the blood and from the intraperitoneal cavity at 6 months were compared.. In both experiments, diabetes was reversed in all transplanted mice, and oral glucose tolerance test showed improved profiles. In general, retrieved islets were viable and functional. However, blood porcine C-peptide concentrations were low at both 2 and 6 months, and concentrations in the ascites of peritoneal cavity were 40 times as high as those in blood.. The peripheral blood sampling for c-peptide, though highly informative in vascularized grafts, may not be the primary tool for monitoring the health and function of encapsulated products when transplanted into intraperitoneal cavity. Our results might explain the clinical feature of the low C-peptide blood concentrations after successful intraperitoneal encapsulated islet transplantation. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Graft Survival; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Mice, Nude; Swine; Transplantation, Heterologous | 2017 |
Glial fibrillary acidic protein (GFAP) is a novel biomarker for the prediction of autoimmune diabetes.
Glial fibrillary acidic protein (GFAP) is expressed in peri-islet Schwann cells, as well as in glia cells, and has been reported to be an autoantigen candidate for type 1 diabetes mellitus (T1DM). We confirmed that the production of the autoantibodies GFAP and glutamic acid decarboxylase 65 (GAD65) was increased and inversely correlated with the concentration of secreted C peptide in female nonobese diabetic mice (T1DM model). Importantly, the development of T1DM in female nonobese diabetic mice at 30 wk of age was predicted by the positive GFAP autoantibody titer at 17 wk. The production of GFAP and GAD65 autoantibodies was also increased in KK-A Topics: Animals; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glial Fibrillary Acidic Protein; Humans; Male; Mice; Mice, Inbred NOD | 2017 |
MRI tracking of autologous pancreatic progenitor-derived insulin-producing cells in monkeys.
Insulin-producing cells (IPCs) derived from a patient's own stem cells offer great potential for autologous transplantation in diabetic patients. However, the limited survival of engrafted cells remains a bottleneck in the application of this strategy. The present study aimed to investigate whether nanoparticle-based magnetic resonance (MR) tracking can be used to detect the loss of grafted stem cell-derived IPCs in a sensitive and timely manner in a diabetic monkey model. Pancreatic progenitor cells (PPCs) were isolated from diabetic monkeys and labeled with superparamagnetic iron oxide nanoparticles (SPIONs). The SPION-labeled cells presented as hypointense signals on MR imaging (MRI). The labeling procedure did not affect the viability or IPC differentiation of PPCs. Importantly, the total area of the hypointense signal caused by SPION-labeled IPCs on liver MRI decreased before the decline in C-peptide levels after autotransplantation. Histological analysis revealed no detectable immune response to the grafts and many surviving insulin- and Prussian blue-positive cell clusters on liver sections at one year post-transplantation. Collectively, this study demonstrates that SPIO nanoparticles can be used to label stem cells for noninvasive, sensitive, longitudinal monitoring of stem cell-derived IPCs in large animal models using a conventional MR imager. Topics: Animals; C-Peptide; Cell Differentiation; Cell Tracking; Contrast Media; Diabetes Mellitus, Type 1; Disease Models, Animal; Ferric Compounds; Humans; Macaca fascicularis; Magnetic Resonance Imaging; Magnetite Nanoparticles; Mesenchymal Stem Cell Transplantation; Pancreatic Polypeptide-Secreting Cells; Transplantation, Autologous | 2017 |
Increased Interleukin-35 Levels in Patients With Type 1 Diabetes With Remaining C-Peptide.
Many patients with long-standing type 1 diabetes have remaining functional β-cells. This study investigated immunological differences between patients with or without measurable remaining endogenous insulin production after ≥10 years duration of disease.. Patients (. The blood concentration of the cytokine IL-35 was markedly lower in C-peptide-negative patients, and this was associated with a simultaneous decrease in the proportion of IL-35. Patients with remaining endogenous β-cell function after >10 years duration of type 1 diabetes differ immunologically from other patients with long-standing type 1 diabetes. In particular, they have a much higher IL-35 production. Topics: Adult; C-Peptide; Case-Control Studies; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Differentiation; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin-Secreting Cells; Interleukin-17; Interleukins; Leukocytes, Mononuclear; Male; Middle Aged; T-Lymphocytes, Regulatory; Th17 Cells | 2017 |
Benefits of Islet Transplantation as an Alternative to Pancreas Transplantation: Retrospective Study of More Than 10 Ten Years of Experience in a Single Center.
Pancreas transplantation (PTx) represents the method of choice in type 1 diabetic patients with conservatively intractable hypoglycemia unawareness syndrome. In 2005, the Institute for Clinical and Experimental Medicine (IKEM) launched a program to investigate the safety potential of islet transplantation (ITx) in comparison to PTx.. This study aims to compare the results of PTx and ITx regarding severe hypoglycemia elimination, metabolic control, and complication rate.. We analyzed the results of 30 patients undergoing ITx and 49 patients treated with PTx. All patients were C-peptide-negative and suffered from hypoglycemia unawareness syndrome. Patients in the ITx group received a mean number of 12,349 (6,387-15,331) IEQ/kg/person administered percutaneously into the portal vein under local anesthesia and radiological control. The islet number was reached by 1-3 applications, as needed. In both groups, we evaluated glycated hemoglobin, insulin dose, fasting and stimulated C-peptide, frequency of severe hypoglycemia, and complications. We used the Mann Whitney test, Wilcoxon signed-rank test, and paired t-test for analysis. We also individually assessed the ITx outcomes for each patient according to recently suggested criteria established at the EPITA meeting in Igls.. Most of the recipients showed a significant improvement in metabolic control one and two years after ITx, with a significant decrease in HbA1c, significant elevation of fasting and stimulated C-peptide, and a markedly significant reduction in insulin dose and the frequency of severe hypoglycemia. Seventeen percent of ITx recipients were temporarily insulin-independent. The results in the PTx group were comparable to those in the ITx group, with 73% graft survival and insulin independence in year 1, 68% 2 years and 55% 5 years after transplantation. There was a higher rate of complications related to the procedure in the PTx group. Severe hypoglycemia was eliminated in the majority of both ITx and PTx recipients.. This report proves the successful initiation of pancreatic islet transplantation in a center with a well-established PTx program. ITx has been shown to be the method of choice for hypoglycemia unawareness syndrome, and may be considered for application in clinical practice if conservative options are exhausted. Topics: Adult; Blood Glucose; C-Peptide; Choice Behavior; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Graft Survival; Humans; Hypoglycemia; Islets of Langerhans Transplantation; Male; Middle Aged; Pancreas Transplantation; Retrospective Studies; Risk Assessment; Syndrome; Young Adult | 2017 |
Autoimmune Hypoglycemia in Type 1 Diabetes Mellitus.
Antibodies against exogenous insulin are common in type 1 diabetes mellitus patients. They can cause hypoglycemia, albeit uncommonly.. A 14-year-old girl with type 1 diabetes mellitus presented with recurrent hypoglycemia.. High insulin, low C-peptide and raised insulin antibody levels documented during hypoglycemia. Plasmapheresis led to remission of hypoglycemia.. Antibodies to exogenous insulin should be considered as a cause of recurrent refractory hypoglycemia in type 1 diabetes mellitus patients. Topics: Adolescent; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Insulin; Insulin Antibodies | 2017 |
Assessment of β Cell Mass and Function by AIRmax and Intravenous Glucose in High-Risk Subjects for Type 1 Diabetes.
There is little information regarding β cell mass in individuals at early stages of type 1 diabetes (T1D).. To investigate both acute insulin response to arginine at hyperglycemia (AIRmax), as a correlate of β cell mass, and β cell function by the intravenous glucose tolerance test (IVGTT) in subjects at early stages of T1D.. Forty subjects were enrolled: (1) low-risk group: relatives of patients with T1D with 0 to 1 antibody (n = 21) and (2) high-risk group: relatives with ≥2 antibodies (n = 19).. Acute insulin and C-peptide responses to IVGTT and to AIRmax. Participants underwent two IVGTT and AIRmax procedures on different days.. AIRmax was reproducible, well tolerated, and correlated to first-phase insulin response (FPIR) from IVGTT (r = 0.779). The high-risk group had greater impaired β cell function compared with the low-risk group, determined both by lower mean FPIR and a greater number of subjects below an established threshold for abnormal function [10 of 19 (52.6%) versus 4 of 21 (19%)]. There was a heterogeneous AIRmax response in these subjects with low FPIR, ranging from 38 to 250 μU/mL.. There is significant variation in insulin secretory reserve as assessed by AIRmax in family members with low β cell function assessed by FPIR. As AIRmax is a functional measure of β cell mass, these data suggest heterogeneity in disease pathogenesis in which mass is preserved in relation to function in some individuals. The tolerability and reproducibility of AIRmax suggest it could be a useful stratification measure in clinical trials of disease-modifying therapy. Topics: Adult; Arginine; C-Peptide; Cell Count; Diabetes Mellitus, Type 1; Female; Glucose; Glucose Tolerance Test; Humans; Hyperglycemia; Insulin; Insulin-Secreting Cells; Male; Pancreatic Function Tests; Reproducibility of Results; Risk | 2017 |
PRESERVED PROINSULIN SECRETION IN LONG-STANDING TYPE 1 DIABETES.
Recent literature has reported preserved residual beta-cell function (C-peptide "microsecretion") in many individuals with long-standing type 1 diabetes (T1D). However, the concentrations of detectable insulin/C-peptide in the serum are usually very low, and beta-cell mass is typically negligible. Proinsulin is measurable in the early years after diagnosis, consistent with the presence of residual functioning beta cells. However, individuals are not expected to secrete significant amounts of proinsulin beyond the early years after diagnosis. Our primary objective was to measure the prohormone, proinsulin, in a heterogeneous cohort of individuals with long-standing T1D. We also sought to assess whether proinsulin secretion might occur in certain individuals despite the absence of measurable C-peptide.. Random postmeal proinsulin concentrations were measured in 97 subjects with T1D (disease duration >3 years) recruited from within the T1D Exchange Clinic Network participants who took part in the Residual C-peptide Study.. Forty-nine of these subjects had undetectable baseline and stimulated C-peptide (C-peptide [-]), and 48 of them had detectable C-peptide concentrations (C-peptide [+]). All the C-peptide (+) subjects had detectable serum proinsulin. Eight (16%) of the C-peptide (-) subjects had detectable serum proinsulin.. We report the observation that proinsulin secretion persists in a proportion of individuals with long-standing T1D, even in the absence of measurable C-peptide. It is not yet clear why certain patients with T1D retain the ability to secrete proinsulin many years after diagnosis.. CP = C-peptide CV = coefficient of variation ELISA = enzyme-linked immunosorbent assay IQR = inter-quartile range MMTT = mixed-meal tolerance test NIBSC = National Institute for Biological Standards and Control PI = proinsulin T1D = type 1 diabetes. Topics: Adult; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Pilot Projects; Proinsulin; Time Factors; Young Adult | 2017 |
External Validation of the Newly Developed BETA-2 Scoring System for Pancreatic Islet Graft Function Assessment.
BETA-2 score using a single fasting blood sample was developed to estimate beta-cell function after islet transplantation (ITx) and was validated internally by a high ITx volume center (Edmonton). The goal was to validate BETA-2 externally, in our center.. Areas under receiver operating characteristic curves (AUROCs) were obtained to see if beta score or BETA-2 would better detect insulin independence and glucose intolerance.. We analyzed values from 48 mixed meal tolerance tests (MMTTs) in 4 ITx recipients with a long-term follow-up to 140 months (LT group) and from 54 MMTTs in 13 short-term group patients (ST group). AUROC for no need for insulin support was 0.776 (95% confidence interval [CI] 0.539-1, P = .02) and 0.922 (95% CI 0.848-0.996, P < .001) for beta score and 0.79 (95% CI 0.596-0.983, P = .003) and 0.941 (95% CI 0.86-1, P < .001) for BETA-2, in LT and ST groups, respectively, and did not differ significantly. In LT group BETA-2 score ≥ 13.03 predicted no need for insulin supplementation with sensitivity of 98%, specificity of 50%, positive predictive value (PPV) of 93%, and negative predictive value (NPV) of 75%. In ST group the optimal cutoff was ≥13.63 with sensitivity of 92% and specificity, PPV, and NPV 82% to 95%. For the detection of glucose intolerance BETA-2 cutoffs were <19.43 in LT group and <17.23 in ST group with sensitivity > 76% and specificity, PPV, and NPV > 80% in both groups.. BETA-2 score was successfully validated externally and is a practical tool allowing for frequent and reliable assessments of islet graft function based on a single fasting blood sample. Topics: Adult; Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Predictive Value of Tests; ROC Curve | 2017 |
Assessment of preservation of beta-cell function in children with long-standing type 1 diabetes with "ultrasensitive c-peptide" method.
Type 1 diabetes mellitus is a disease caused by the autoimmune destruction of pancreatic beta-cells. It was previously believed that the loss of the endocrine function of the pancreas is total and inevitable. With the rise of new knowledge and new methods allowing to reliably measure c-peptide in the low plasma concentration range, we have learned otherwise. Some residual function of the beta-cells can be present even after decades of the course of the disease. The aim of the study was to evaluate the c-peptide level with routine laboratory and ultrasensitive methods in children with long-standing type 1 diabetes in relation to clinical characteristics.. We recruited 178 consecutive children with type 1 diabetes mellitus lasting at least 1 year, mean diabetes duration was 5.6 years. Basic anthropometric measurements were performed and blood samples were drawn. From patients history records we gathered data regarding the course of the disease and laboratory results previously acquired. Laboratory tests performed on the blood samples included HbA1c levels and c-peptide level measurement using classic (n=178) and ultrasensitive (n=160) method (Mercodia). Clinically relevant c-peptide level was set at 0.23 ng/ml according to the DCCT recommendations.. Clinically relevant c-peptide was found in 54 of 160 (33.75%) patients. Patients with preserved c-peptide were older at the time of diagnosis, had longer clinical remission, and required lower total and basal doses of insulin. Significantly lower mean HbA1c from the last year, but higher HbA1c at the time of the diabetes diagnosis were found in the group with higher c-peptide levels. The comparison of the classic and ultrasensitive c-peptide tests revealed that both yield similar results.. Our observation shows that 34% of young patients with long-standing type 1 diabetes have prolonged c-peptide secretion. We confirm the long-standing assumption that residual beta-cell function is beneficial for metabolic control of the patients. Classic method of the c-peptide measurement can be just as useful in clinical practice as the ultrasensitive one.. Wstęp. Cukrzyca typu 1 jest autoimmunizacyjną chorobą, w której zniszczeniu ulegają komórki beta wysp trzustkowych. Jeszcze do niedawna sądzono, że utrata wewnątrzwydzielniczej funkcji trzustki jest całkowita i nieunikniona. Jednak wraz z rozwojem wiedzy oraz powstaniem nowych wiarygodnych metod oznaczania c-peptydu przy jego bardzo niskich stężeniach okazało się, że szczątkowa funkcja gruczołu może być zachowana nawet dekady od diagnozy. Celem badania była ocena stężenia c-peptydu za pomocą rutynowej metody laboratoryjnej oraz nowej metody ultraczułej u dzieci z długotrwającą cukrzycą typu 1 w relacji do charakterystyki klinicznej pacjentów. Metody. Do badania włączyliśmy 178 kolejnych pacjentów z cukrzycą typu 1 trwającą co najmniej 1 rok, średni czas trwania cukrzycy wynosił 5,6 lat. Zostały wykonane podstawowe pomiary antropometryczne oraz pobrane próbki krwi. Z medycznych historii pacjentów zebrano informacje dotyczące przebiegu choroby i wcześniejszych wyników laboratoryjnych. W pobranych próbkach krwi oznaczono wartość HbA1c oraz stężenie c-peptydu metodą klasyczną (n=178) i ultraczułą (n=160) (Mercodia). Klinicznie istotne stężenie c-peptydu uznano przy wartości 0,23 ng/ml zgodnie z rekomendacjami DCCT. Wyniki. Klinicznie istotne stężenie c-peptydu stwierdzono u 54 z 160 pacjentów (33,75%). Pacjenci z zachowanym stężeniem c-peptydu byli starsi w czasie diagnozy, mieli dłuższy okres remisji i wymagali mniejszych całkowitych i bazalnych dawek insuliny. W grupie z zachowanym wydzielaniem c-peptydu stwierdzono istotnie niższą średnią wartość HbA1c z ostatniego roku i wyższą wartość HbA1c w momencie diagnozy choroby. Porównując klasyczną i ultraczułą metodę oznaczania c-peptydu, uzyskaliśmy podobne wyniki. Wnioski. Wykazano zachowane wydzielanie c-peptydu u 34% dzieci z długotrwająca cukrzycą typu 1. Nasze obserwacje potwierdzają przypuszczenie, że szczątkowa funkcja komórek beta wysp trzustki (mierzona stężeniem c-peptydu) jest korzystna dla wyrównania metabolicznego pacjentów. Klasyczna metoda oznaczania stężenia c-peptydu może być równie przydatna w praktyce klinicznej, jak metoda ultraczuła. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin-Secreting Cells | 2017 |
Coexisting psoriasis affects the clinical course of type 1 diabetes in children.
Literature reports link psoriasis with insulin resistance characteristic for type 2 diabetes. However, this condition may also affect the clinical course of type 1 diabetes (T1D).. To investigate whether children with type 1 diabetes mellitus (T1D) and psoriasis have a different course of diabetes.. We evaluated patients diagnosed with T1D in the years 2002-2011 for the presence of psoriasis and matched them 1:10 with T1D-only patients by sex and duration of diabetes using propensity score. We collected T1D-onset parameters and metabolic control surrogates from six months after T1D diagnosis.. We identified 14 patients with psoriasis and matched 140 controls, of whom 129 (68 boys) were eligible for the analysis. At onset T1D+psoriasis patients showed higher concentration of C-peptide than controls (median: 0.38ng/ml vs 0.15ng/ml, p=0.02). Six months later, they had non-significantly lower HbA1c (6.0 vs 6.6%, p=0.11), TC (143mg/dl vs 159mg/dl, p=0.14) HDL (54.5mg/dl vs 59mg/dl, p=0.11).. Patients with T1D and psoriasis present higher endogenous insulin secretion at T1D onset and a tendency for better glycemic control during the first 6 months.. Wstęp. W doniesieniach literatury łuszczyca wiąże się z insulinoopornością, charakterystyczną dla cukrzycy typu 2. Potencjalnie stan ten może wpływać również na przebieg cukrzycy typu 1 (T1D). Cel pracy. Zbadanie, czy pacjenci pediatryczni z cukrzycą typu 1 i łuszczycą prezentują odmienny przebieg cukrzycy. Materiał i metody. Pacjenci z T1D zdiagnozowaną w latach 2002–2011 zostali retrospektywnie ocenieni w poszukiwaniu towarzyszącej łuszczycy. Do wyłonionej w ten sposób grupy dobrano kontrolę dzieci z samą T1D w stosunku 1:10 pod kątem płci i czasu trwania cukrzycy. Zebrano dane kliniczne z okresu rozpoznania cukrzycy oraz parametry wyrównania metabolicznego z wizyt kontrolnych po 6 miesiącach od rozpoznania cukrzycy. Wyniki. Zidentyfikowano 14 pacjentów z T1D i łuszczycą, dobrano 140 pacjentów z grupy kontrolnej, z których łącznie 129 (68 chłopców) włączono do analizy. W porównaniu do grupy kontrolnej pacjenci z T1D i łuszczycą charakteryzowali się wyższym stężeniem C-peptydu podczas rozpoznania T1D (mediana 0,38ng/ml vs 0,15ng/ml, p=0,02) oraz nieistotnie niższym stężeniem hemoglobiny glikowanej (6,0 vs 6,6%, p=0,11), całkowitego cholesterolu (143mg/dl vs 159mg/dl, p=0,14) i cholesterolu HDL (54,5mg/dl vs 59mg/dl, p=0,11) po 6 miesiącach od rozpoznania cukrzycy. Wnioski. Pacjenci z T1D i towarzyszącą łuszczycą wykazują wyższe stężenia endogennej insuliny w chwili rozpoznania cukrzycy oraz mają tendencję do lepszego wyrównania cukrzycy w trakcie pierwszych 6 miesięcy choroby. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Male; Psoriasis | 2017 |
The Differentiation Potential of Human Natal Dental Pulp Stem Cells into Insulin-Producing Cells.
Mesenchymal stem cells have the ability to differentiate into insulin-producing cells, raising the hope for diabetes mellitus treatment. The aim of this research was to study the ability of stem cells from discarded natal teeth to differentiate into insulinproducing cells. Two vital human natal teeth were obtained from a healthy 2-day-old female. Stem cells from the dental pulp were isolated, cultured under xenogenic-free conditions, propagated and characterized. Proliferative activity, population doubling time and viability were measured, and the multipotent differentiation ability was investigated. A twostep protocol was used to induce the human natal dental pulp stem cells to differentiate into insulinproducing cells. Phenotypic analysis was done using flow cytometry. Immunohistochemistry was performed to detect insulin and C-peptide. PDX1, HES1 and Glut2 gene expression analysis was performed by quantitative reverse transcription-polymerase chain reaction. Human natal dental pulp stem cells were able to undergo osteogenic, chondrogenic and adipogenic differentiation upon exposure to the specific differentiation media for each lineage. Their differentiation into insulin-producing cells was confirmed by expression of C-peptide and insulin, as well as by 975.4 % higher expression of PDX-1 and 469.5 % higher expression of HES1 in comparison to the cells cultivated in standard cultivation media. Glut2 transporter mRNA was absent in the non-differentiated cells, and differentiation of the stem cells into insulin-producing cells induced appearance of the mRNA of this transporter. We were the first to demonstrate that stem cells obtained from the pulp of natal teeth could be differentiated into insulinproducing cells, which might prove useful in the stem cell therapy for type 1 diabetes. Topics: C-Peptide; Cell Differentiation; Cells, Cultured; Dental Pulp; Diabetes Mellitus, Type 1; Female; Flow Cytometry; Homeodomain Proteins; Humans; Immunohistochemistry; Insulin; Insulin-Secreting Cells; Mesenchymal Stem Cells; Stem Cells; Trans-Activators; Transcription Factor HES-1 | 2017 |
Insulin, insulin antibodies and insulin autoantibodies.
Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Antibodies | 2017 |
Role of the C1858T polymorphism of protein tyrosine phosphatase non-receptor type 22 (PTPN22) in children and adolescents with type 1 diabetes.
In recent years, increasing interest has been devoted to the susceptibility gene polymorphisms in type 1 diabetes (T1D) as well as in other autoimmune diseases. Among these, a nucleotide polymorphism of the gene encoding for the protein tyrosine phosphatase non-receptor type 22 (PTPN22) has been associated with T1D in several studies. The aim of this study is to define the frequency of the C1858T polymorphism in the PTPN22 gene in a cohort of 113 Caucasian patients (58 males and 55 females) with T1D, and to assess a possible correlation with a group of clinically relevant variables: age at onset, gender, diabetes-related autoantibodies, residual β-cell function and daily insulin requirement (IR) 6 months after diagnosis. Using a PCR-RFLP approach, we evidenced a 17.7% frequency of the PTPN22 C1858T polymorphism in diabetic patients, higher than the frequency showed in the general population. A statistically significant correlation between this polymorphism and higher levels of C-peptide at diagnosis and lower IR at 6 months from diagnosis was observed (P=0.001 and P=0.04). Moreover, 1858T variant carriers were more frequently positive for glutamic acid decarboxylase (GAD) autoantibodies at diagnosis than wild-type subjects (P=0.19). On the other hand, no significant difference regarding age at onset, gender distribution, insulinoma-associated 2 molecule (IA2) and islet cell antibodies (ICA) positivity was found. These findings, if adequately confirmed in the future and extended to larger samples, may characterize a subset of T1D patients with a defined genetic pattern, who may be eligible for trials aimed to preserve residual β-cell function in the coming years. Topics: Adolescent; Age Factors; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genetic Predisposition to Disease; Glutamate Decarboxylase; Glycated Hemoglobin; Heterozygote; Homozygote; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Pharmacogenetics; Pharmacogenomic Variants; Phenotype; Polymorphism, Single Nucleotide; Protein Tyrosine Phosphatase, Non-Receptor Type 22; Risk Factors; Time Factors; Treatment Outcome | 2017 |
Dissecting heterogeneity in paediatric Type 1 diabetes: association of TCF7L2 rs7903146 TT and low-risk human leukocyte antigen (HLA) genotypes.
To test the hypothesis that non-obese individuals with childhood-onset Type 1 diabetes and the rs7903146 TT genotype would be less likely to have high-risk human leukocyte antigen (HLA) genotypes and alleles.. We studied a cohort of 105 non-obese participants in the T1D Exchange Biobank Residual Insulin Study who had childhood-onset Type 1 diabetes [mean (sd) age at onset and recruitment, respectively, 9.9 (4.15) and 14.4 (4.13) years; 84.8% non-Hispanic white]. We analysed islet autoantibodies (glutamic acid decarboxylase 65, islet cell autoantigen 512/islet antigen-2 and zinc transporter 8), non-fasting random C-peptide levels, HLA type and TCF7L2 single nucleotide polymorphism rs7903146 in this cohort.. None of the 13 individuals with the rs7903146 TT genotype carried the highest Type 1 diabetes risk HLA genotype, i.e. DRB1*03:01/DR4 (DRB1*0401, *04:05 or *04:02), compared with 29.4% (27/92) of those without it (P=0.023). The DRB1*03:01 allele was present in 15.4% (2/13) of individuals with the single nucleotide polymorphism, compared with 59.8% (55/92) of those without it (P=0.003). Analyses restricted to autoantibody-positive individuals (n=80) yielded similar results. The HLA DRB1*15:01 allele, which affords dominant protection against Type 1 diabetes, was found in one participant, who had multiple islet autoantibodies and carried the rs7903146 TT genotype.. These findings further support the hypothesis that TCF7L2 gene variation contributes to diabetogenesis in a subset of young people with Type 1 diabetes, opening possible new pathways for therapy and prevention. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Glutamate Decarboxylase; HLA-DRB1 Chains; Humans; Male; Polymorphism, Single Nucleotide; Transcription Factor 7-Like 2 Protein; Zinc Transporter 8 | 2017 |
Long-term Metabolic Outcomes of Functioning Pancreas Transplants in Type 2 Diabetic Recipients.
Limited data are available regarding the long-term metabolic outcomes of functioning pancreas transplants in patients with type 2 diabetes mellitus (T2DM).. To compare the long-term effects of pancreas transplantation in terms of insulin resistance and β cell function, comparison of metabolic variables was performed between type 1 diabetes mellitus (T1DM) and T2DM patients from 1-month posttransplant to 5 years using generalized, linear-mixed models for repeated measures.. Among 217 consecutive patients who underwent pancreas transplantation at our center between August 2004 and January 2015, 193 patients (151 T1DM and 42 T2DM) were included in this study. Throughout the follow-up period, postoperative hemoglobin A1c did not differ significantly between T1DM and T2DM patients, and the levels were constantly below 6% (42 mmol/mol) until 5 years posttransplant, whereas C-peptide was significantly higher in T2DM (P = 0.014). There was no difference in fasting insulin, homeostasis model assessment (HOMA) of insulin resistance, HOMA β cell, or the insulinogenic index between the groups. Furthermore, fasting insulin and HOMA-insulin resistance steadily decreased in both groups during the follow-up period.. There was no significant difference in the insulin resistance or β-cell function after pancreas transplantation between T1DM and T2DM patients. We demonstrated that pancreas transplantation is capable of sustaining favorable endocrine functions for more than 5 years in T2DM recipients. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Chi-Square Distribution; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Graft Survival; Humans; Insulin; Insulin Resistance; Insulin-Secreting Cells; Kaplan-Meier Estimate; Linear Models; Male; Middle Aged; Pancreas Transplantation; Retrospective Studies; Risk Factors; Time Factors; Treatment Outcome | 2017 |
Clinical characteristics of type 1 diabetes mellitus in Taiwanese children aged younger than 6 years: A single-center experience.
Cases of type 1 diabetes mellitus in children aged younger than 6 years in Taiwan has increased in the past 10 years. This retrospective study aimed to review the management experience of such patients in a single center.. From January 2004 to June 2015, 52 newly diagnosed diabetic children younger than 6 years who had regular follow-up for > 1 year were enrolled, as well as 94 older diabetic children for comparison. Their medical records were thoroughly reviewed.. The most common symptoms and signs were polyuria, polydipsia, dry lips, weight loss, and nocturia. Among the children younger than 6 years, 87% had ketoacidosis upon diagnosis-significantly higher than that of the older age group-and 88% had at least one islet cell autoantibody detected. Their serum C-peptide levels were significantly lower and the frequency of insulin autoantibodies detected was significantly higher compared with the older age group (37% vs. 10%). The remission rate of the young diabetic patients was significantly lower than that of the older age group (40% vs. 59%), but there was no difference in time of onset and duration of remission between the two groups.. Autoimmune destruction of pancreatic β-cells is an important cause of type 1 diabetes mellitus in Taiwanese children aged younger than 6 years. These patients usually have a low insulin reserve and severe ketoacidosis upon diagnosis. A high index of suspicion in the presence of classic symptoms of diabetes in young children is important to prevent complications. Topics: Adolescent; Age Factors; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Humans; Lip; Male; Nocturia; Polydipsia; Polyuria; Symptom Assessment; Taiwan; Weight Loss | 2017 |
Circulating adiponectin concentration is inversely associated with glucose tolerance and insulin secretion in people with newly diagnosed diabetes.
To examine the hypothesis that changes in serum adiponectin concentration inversely relate to changes in glucose tolerance and β-cell function already during the early stage of disease progression in recently diagnosed Type 1 and Type 2 diabetes mellitus.. Participants in the prospective observational German Diabetes Study (Type 2 diabetes, n = 94; Type 1 diabetes, n = 42) underwent i.v. glucose tolerance and glucagon stimulation testing to assess pre-hepatic β-cell function, glucose tolerance index and C-peptide secretion within the first year of diabetes diagnosis and 2 years later. Associations of changes in serum concentrations of total adiponectin, high-molecular-weight adiponectin and their ratio with changes in the aforementioned metabolic variables were calculated using linear regression.. Among people with Type 2 diabetes, 2-year increases in high-molecular-weight adiponectin and in high-molecular-weight/total adiponectin ratio were associated with decreases in glucose tolerance index of 0.1%/min (P = 0.020) and 0.8%/min (P = 0.013), respectively. Increases in high-molecular-weight/total adiponectin ratio were related to decreases in acute C-peptide secretion of 54.6% (P = 0.020). Among people with Type 1 diabetes, 2-year increases in total adiponectin were associated with 2-year decreases in acute C-peptide secretion of 56.2% (P = 0.035).. Increases in adiponectin concentrations in the first 2 years after diagnosis were related to a worsening of acute insulin secretion and glucose tolerance index in Type 1 and Type 2 diabetes. (Clinical Trials Registry no.: NCT01055093). Topics: Adiponectin; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Prognosis; Prospective Studies; Young Adult | 2017 |
Age and Early Graft Function Relate With Risk-Benefit Ratio of Allogenic Islet Transplantation Under Antithymocyte Globulin-Mycophenolate Mofetil-Tacrolimus Immune Suppression.
Induction therapy with a T cell-depleting agent followed by mycophenolate mofetil and tacrolimus is presently the most frequently used immune suppression (IS) regimen in islet transplantation. This study assesses its safety and tolerability in nonuremic type 1 diabetic recipients.. Fifty-one patients (age, between 29 and 63 years) with high glycemic variability and problematic hypoglycemia received intraportal islet grafts under anti-thymocyte globulin-mycophenolate mofetil-tacrolimus protocol. They were followed up for over 48 months for function of the implant and adverse events.. Severe hypoglycemia and diabetic ketoacidosis were absent in patients with functioning graft. Immune suppressive therapy was maintained for 48 months in 29 recipients with sustained function (group A), whereas 16 patients stopped earlier due to graft failure (group B) and in 6 for other reasons. Group A was significantly older at the time of implantation and achieved higher graft function at posttransplantation month 6 under similar dose of IS. Prevalence of IS-related side effects was similar in groups A and B, occurring predominantly during the first year posttransplantation. IS-related serious adverse events (SAE) were reported in 47% of patients, with 4 presenting with cytomegalovirus infection and 4 (age, 42-59 years) diagnosed with cancer. Except in 1 patient with cancer, all SAEs resolved after appropriate treatment.. These risk/benefit data serve as a basis for clinical decision-making before entering an intraportal islet transplantation protocol. A longer benefit is observed in recipients of higher age (≥40 years), but it is not associated with more side effects and SAE. Topics: Adult; Antilymphocyte Serum; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Islets of Langerhans Transplantation; Male; Middle Aged; Mycophenolic Acid; Postoperative Complications; Risk Assessment; Risk Factors; Tacrolimus; Time Factors; Transplantation, Homologous; Treatment Outcome | 2017 |
Metabolite Profiling of LADA Challenges the View of a Metabolically Distinct Subtype.
Latent autoimmune diabetes in adults (LADA) usually refers to GAD65 autoantibodies (GADAb)-positive diabetes with onset after 35 years of age and no insulin treatment within the first 6 months after diagnosis. However, it is not always easy to distinguish LADA from type 1 or type 2 diabetes. In this study, we examined whether metabolite profiling could help to distinguish LADA ( Topics: Adult; Age of Onset; Autoantibodies; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Gas Chromatography-Mass Spectrometry; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Latent Autoimmune Diabetes in Adults; Male; Metabolome; Middle Aged; Principal Component Analysis; Sweden; Young Adult | 2017 |
Islet-Derived CD4 T Cells Targeting Proinsulin in Human Autoimmune Diabetes.
Type 1 diabetes results from chronic autoimmune destruction of insulin-producing β-cells within pancreatic islets. Although insulin is a critical self-antigen in animal models of autoimmune diabetes, due to extremely limited access to pancreas samples, little is known about human antigenic targets for islet-infiltrating T cells. Here we show that proinsulin peptides are targeted by islet-infiltrating T cells from patients with type 1 diabetes. We identified hundreds of T cells from inflamed pancreatic islets of three young organ donors with type 1 diabetes with a short disease duration with high-risk HLA genes using a direct T-cell receptor (TCR) sequencing approach without long-term cell culture. Among 85 selected CD4 TCRs tested for reactivity to preproinsulin peptides presented by diabetes-susceptible HLA-DQ and HLA-DR molecules, one T cell recognized C-peptide amino acids 19-35, and two clones from separate donors responded to insulin B-chain amino acids 9-23 (B:9-23), which are known to be a critical self-antigen-driving disease progress in animal models of autoimmune diabetes. These B:9-23-specific T cells from islets responded to whole proinsulin and islets, whereas previously identified B:9-23 responsive clones from peripheral blood did not, highlighting the importance of proinsulin-specific T cells in the islet microenvironment. Topics: Adolescent; Autoantigens; C-Peptide; CD4-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; HLA-DQ Antigens; HLA-DR Antigens; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Peptide Fragments; Proinsulin; Protein Precursors; Receptors, Antigen, T-Cell; Young Adult | 2017 |
Evaluating the potential of the GFAP-KLH immune-tolerizing vaccine for type 1 diabetes in mice.
Glial fibrillary acidic protein (GFAP), expressed in peri-islet Schwann cells, is a novel target for the treatment of type 1 diabetes mellitus (T1DM). We designed a GFAP immune-tolerizing vaccine that successfully suppresses hyperglycemia and enhances C peptide secretion. The GFAP vaccine significantly prevented T cell infiltration into pancreatic islets. Moreover, after GFAP vaccination, naïve T-cell differentiation shifted from a cytotoxic Th1- to a Th2-biased humoral response. These results indicate that as a novel target, GFAP reliably predicts the development of T1DM, and that the GFAP vaccine successfully delays the progression of T1DM by regulating T-cell differentiation. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Female; Glial Fibrillary Acidic Protein; Hemocyanins; Immune Tolerance; Immunity; Immunoglobulin G; Interferon-gamma; Interleukin-4; Mice, Inbred NOD; Pancreas; Phenotype; Th1 Cells; Th2 Cells; Vaccination; Vaccines | 2017 |
Factors Associated with the Presence and Severity of Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes in Korean Children and Adolescents.
The aim of this study was to identify the risk factors for presence and severity of diabetic ketoacidosis (DKA) at the onset of type 1 diabetes mellitus (T1DM) in Korean children and adolescents. A retrospective chart review of children and adolescents newly diagnosed with T1DM was conducted in seven secondary and tertiary centers in Korea. Eligible subjects were < 20 years of age and had records on the presence or absence of DKA at the time of T1DM diagnosis. DKA severity was categorized as mild, moderate, or severe. Data were collected on age, height, body weight, pubertal status, family history of diabetes, delayed diagnosis, preceding infections, health insurance status, and parental education level. A total of 361 patients (male 46.3%) with T1DM were included. Overall, 177 (49.0%) patients presented with DKA at T1DM diagnosis. Risk factors predicting DKA at T1DM diagnosis were age ≥ 12 years, lower serum C-peptide levels, presence of a preceding infection, and delayed diagnosis. Low parental education level and preceding infection increased the severity of DKA. These results suggest that alertness of the physician and public awareness of diabetes symptoms are needed to decrease the incidence and severity of DKA at T1DM diagnosis. Topics: Adolescent; Asian People; Body Weight; C-Peptide; Child; Child, Preschool; Delayed Diagnosis; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Male; Republic of Korea; Retrospective Studies; Risk Factors; Severity of Illness Index; Tertiary Care Centers | 2017 |
A case of idiopathic type 1 diabetes with subsequent recovery of endogenous insulin secretion despite initial diagnosis of fulminant type 1 diabetes.
Fulminant type 1 diabetes is characterized by remarkably rapid and complete β-cell destruction. The established diagnostic criteria include the occurrence of diabetic ketosis soon after the onset of hyperglycemic symptoms, elevated plasma glucose with relatively low HbA1c at the first visit, and extremely low C-peptide. Serum C-peptide levels remain extremely low over a prolonged period. A 26-year-old-man with diabetic ketosis was admitted to our hospital. His relatively low HbA1c (7.6%), despite marked hyperglycemia (593 mg/dL) with marked ketosis, indicated abrupt onset. Islet-related autoantibodies were all negative. His data at onset, including extremely low serum C-peptide (0.11 ng/mL), fulfilled the diagnostic criteria for fulminant type 1 diabetes. However, his fasting serum C-peptide levels subsequently showed substantial recovery. While fasting C-peptide stayed below 0.30 ng/mL during the first two months post onset, the levels gradually increased and thereafter fluctuated between 0.60 ng/mL and 0.90 ng/mL until 24 months post onset. By means of multiple daily insulin injection therapy, his glycemic control has been well maintained (HbA1c approximately 6.0%), with relatively small glycemic fluctuations evaluated by continuous glucose monitoring. This clinical course suggests that, despite the abrupt diabetes onset with extremely low C-peptide levels, substantial numbers of β-cells had been spared destruction and their function later showed gradual recovery. Diabetes has come to be considered a much more heterogeneous disease than the present subdivisions suggest. This case does not fit into the existing concepts of either fulminant type 1 or ketosis-prone diabetes, thereby further highlighting the heterogeneity of idiopathic type 1 diabetes. Topics: Adult; Blood Glucose; C-Peptide; Combined Modality Therapy; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Japan; Male; Severity of Illness Index; Treatment Outcome | 2017 |
Neu5Gc and α1-3 GAL Xenoantigen Knockout Does Not Affect Glycemia Homeostasis and Insulin Secretion in Pigs.
Xenocell therapy from neonate or adult pig pancreatic islets is one of the most promising alternatives to allograft in type 1 diabetes for addressing organ shortage. In humans, however, natural and elicited antibodies specific for pig xenoantigens, α-(1,3)-galactose (GAL) and Topics: Animals; Antigens, Heterophile; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Galactose; Gene Knockout Techniques; Glucagon; Glucose; Homeostasis; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Neuraminic Acids; Pancreas; Purinergic P1 Receptor Antagonists; Swine; Theophylline; Transplantation, Heterologous | 2017 |
Serum undercarboxylated osteocalcin correlates with hemoglobin A1c in children with recently diagnosed pediatric diabetes.
Osteocalcin (OC), a hormone secreted by osteoblasts, improves beta-cell function in vitro and in vivo. We aimed to understand the relationship between OC and hemoglobin A1c (HbA1c) in pediatric diabetes.. Children (n = 70; mean [SD] age = 11.8 years [3.1]; 34.3% non-Hispanic white, 46.3% Hispanic, 14.9% African-American, 4.5% other) newly diagnosed with diabetes (69.1% type 1 diabetes [T1D], 30.9% type 2 diabetes [T2D]) were studied. We collected clinical data at diagnosis and first clinical visit (V1) 9 weeks later (interquartile range [IQR] = 7.9-12.0). Serum undercarboxylated OC (uOC) and carboxylated OC (cOC) were measured 7.0 weeks (IQR 4.3-8.9) after diagnosis.. Mean [SD] uOC was 20.3 (19.6) ng/mL, cOC 29.7 [13.7] ng/mL and u/cOC 0.68 [0.81]. uOC, cOC, or u/cOC were not different by gender, race/ethnicity, age, diabetes type, BMI percentile, or random C-peptide, glucose or HbA1c at diagnosis. However, among 61 children with V1 within 4 months of diagnosis, uOC was higher in those with V1 HbA1c < 7.5% (HbA1c < 58 mmol/mol) (uOC=33.1 [22.0]) compared with children with HbA1c ≥ 7.5% (uOC=17.4 [2.3], P = .0004). The difference was larger among patients with T2D (34.6 and 4.7 ng/mL, respectively, P = .0001) than T1D (32.2 and 19.3, P = .0169), and in males (36.1 and 17.4, P = .018) than females (27.6 and 17.3, P = .072). Analysis for u/cOC were similar while there were no differences in cOC. uOC was inversely correlated with HbA1c at V1 (Spearman's rho = -0.29, P = .02).. Our findings suggest that serum uOC is inversely related to HbA1c shortly after diagnosis of pediatric diabetes. This potentially modifiable factor of glucose metabolism warrants further studies. Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Osteocalcin; Prospective Studies | 2017 |
Residual beta-cell function in diabetes children followed and diagnosed in the TEDDY study compared to community controls.
To explore whether children diagnosed with type 1 diabetes during islet autoantibody surveillance through The Environmental Determinants of Diabetes in the Young (TEDDY) study retain greater islet function than children diagnosed through the community.. TEDDY children identified at birth with high-risk human leukocyte antigen and followed every 3 months until diabetes diagnosis were compared to age-matched children diagnosed with diabetes in the community. Both participated in long-term follow up after diagnosis. Hemoglobin A1c (HbA1c) and mixed meal tolerance test were performed within 1 month of diabetes onset, then at 3, 6, and 12 months, and biannually thereafter.. Comparison of 43 TEDDY and 43 paired control children showed that TEDDY children often had no symptoms (58%) at diagnosis and none had diabetic ketoacidosis (DKA) compared with 98% with diabetes symptoms and 14% DKA in the controls (P < 0.001 and P = 0.03, respectively). At diagnosis, mean HbA1c was lower in TEDDY (6.8%, 51 mmol/mol) than control (10.5%, 91 mmol/mol) children (P < 0.0001). TEDDY children had significantly higher area under the curve and peak C-peptide values than the community controls throughout the first year postdiagnosis. Total insulin dose and insulin dose-adjusted A1c were lower throughout the first year postdiagnosis for TEDDY compared with control children.. Higher C-peptide levels in TEDDY vs community-diagnosed children persist for at least 12 months following diabetes onset and appear to represent a shift in the disease process of about 6 months. Symptom-free diagnosis, reduction of DKA, and the potential for immune intervention with increased baseline C-peptide may portend additional long-term benefits of early diagnosis. Topics: C-Peptide; Case-Control Studies; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Population Surveillance; Prospective Studies | 2017 |
Intralymphatic Injection of Autoantigen in Type 1 Diabetes.
Topics: Area Under Curve; Autoantigens; C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Glutamate Decarboxylase; Historically Controlled Study; Humans; Injections, Intralymphatic; Pilot Projects; Vitamin D; Vitamins; Young Adult | 2017 |
Increase in Peripheral Blood Intermediate Monocytes is Associated with the Development of Recent-Onset Type 1 Diabetes Mellitus in Children.
Monocytes play important roles in antigen presentation and cytokine production to achieve a proper immune response, and are therefore largely implicated in the development and progression of autoimmune diseases. The aim of this study was to analyze the change in the intermediate (CD14+CD16+) monocyte subset in children with recent-onset type 1 diabetes mellitus (T1DM) and its possible association with clinical parameters reflecting islet β-cell dysfunction. Compared with age- and sex-matched healthy controls, intermediate monocytes were expanded in children with T1DM, which was positively associated with hemoglobin A1C and negatively associated with serum insulin and C-peptide. Interestingly, the intermediate monocytes in T1DM patients expressed higher levels of human leukocyte antigen-DR and CD86, suggesting better antigen presentation capability. Further analysis revealed that the frequency of CD45RO+CD4+ memory T cells was increased in the T1DM patients, and the memory T cell content was well correlated with the increase in intermediate monocytes. These results suggest that expanded intermediate monocytes are a predictive factor for the poor residual islet β-cell function in children with recent-onset T1DM. Topics: Adolescent; C-Peptide; CD4-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin-Secreting Cells; Lipopolysaccharide Receptors; Male; Monocytes; Receptors, IgG | 2017 |
Leptin Levels in Patients with Type 1 Diabetes Mellitus After Fetal Pancreatic Stem Cell Transplant.
Our objective was to determine leptin levels in patients with type 1 diabetes mellitus after fetal pancreatic stem cell transplant.. Seven patients, aged 20 to 42 years, with type 1 diabetes mellitus received a fetal pancreatic stem cell transplant by intravenous infusion. The quantity of fetal stem cells infused was ≥ 5 × 10⁶, and the cells were of 12 to 14 weeks of gestation. We analyzed the levels of leptin, C-peptide, and antibodies to the islets of Langerhans before and 3 months after the transplant procedure.. Fetal pancreatic stem cell transplant led to significant increases in leptin and C-peptide levels, from 4.63 ± 1.17 ng/mL and 0.09 ± 0.02 ng/mL to 7.71 ± 1.45 ng/mL (P < .05) and 0.22 ± 0.05 ng/mL (P < .005), respectively, without an increase in antibodies to the islets of Langerhans, which measured 0.64 ± 0.13 U/mL before transplant and 0.57 ± 0.18 U/mL 3 months later (P > .05).. Leptin levels increase significantly within 3 months of fetal pancreatic stem cell transplant in patients with type 1 diabetes mellitus. Topics: Adult; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Stem Cells; Humans; Leptin; Male; Pancreas Transplantation; Time Factors; Treatment Outcome; Up-Regulation; Young Adult | 2017 |
Proinsulin and heat shock protein 90 as biomarkers of beta-cell stress in the early period after onset of type 1 diabetes.
Rapid evaluation of therapies designed to preserve β cells in persons with type 1 diabetes (T1D) is hampered by limited availability of sensitive β-cell health biomarkers. In particular, biomarkers elucidating the presence and degree of β-cell stress are needed. We characterized β-cell secretory activity and stress in 29 new-onset T1D subjects (10.6 ± 3.0 years, 55% male) at diagnosis and then 8.2 ± 1.2 weeks later at first clinic follow-up. We did comparisons with 16 matched healthy controls. We evaluated hemoglobin A1c (HbA1c), β-cell function (random C-peptide [C] and proinsulin [PI]), β-cell stress (PI:C ratio), and the β-cell stress marker heat shock protein (HSP)90 and examined these parameters' relationships with clinical and laboratory characteristics at diagnosis. Mean diagnosis HbA1c was 11.3% (100 mmol/mol) and 7.6% (60 mmol/mol) at follow-up. C-peptide was low at diagnosis (P < 0.001 vs controls) and increased at follow-up (P < 0.001) to comparable with controls. PI did not differ from controls at diagnosis but increased at follow-up (P = 0.003) signifying increased release of PI alongside improved insulin secretion. PI:C ratios and HSP90 concentrations were elevated at both time points. Younger subjects had lower C-peptide and greater PI, PI:C, and HSP90. We also examined islets isolated from prediabetic nonobese diabetic mice and found that HSP90 levels were increased ∼4-fold compared with those in islets isolated from matched CD1 controls, further substantiating HSP90 as a marker of β-cell stress in T1D. Our data indicate that β-cell stress can be assessed using PI:C and HSP90. This stress persists after T1D diagnosis. Therapeutic approaches to reduce β-cell stress in new-onset T1D should be considered. Topics: Adolescent; Aging; Animals; Biomarkers; Blood Glucose; C-Peptide; Case-Control Studies; Child; Diabetes Mellitus, Type 1; Female; HSP90 Heat-Shock Proteins; Humans; Insulin-Secreting Cells; Male; Mice; Proinsulin; Stress, Physiological | 2016 |
Long-Term Follow-Up of the Edmonton Protocol of Islet Transplantation in the United States.
We report the long-term follow-up of the efficacy and safety of islet transplantation in seven type 1 diabetic subjects from the United States enrolled in the multicenter international Edmonton Protocol who had persistent islet function after completion of the Edmonton Protocol. Subjects were followed up to 12 years with serial testing for sustained islet allograft function as measured by C-peptide. All seven subjects demonstrated continued islet function longer than a decade from the time of first islet transplantation. One subject remained insulin independent without the need for diabetic medications or supplemental transplants. One subject who was insulin-independent for over 8 years experienced graft failure 10.9 years after the first islet transplant. The remaining six subjects demonstrated continued islet function upon trial completion, although three had received a supplemental islet transplant each. At trial completion, five subjects were receiving insulin and two remained insulin independent, although one was treated with liraglutide. The median hemoglobin A1c was 6.3% (45 mmol/mol). All subjects experienced progressive decline in the C-peptide/glucose ratio. No patients experienced severe hypoglycemia, opportunistic infection, or lymphoma. Thus, although the rate and duration of insulin independence was low, the Edmonton Protocol was safe in the long term. Alternative approaches to islet transplantation are under investigation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Graft Survival; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Prognosis; Risk Factors | 2016 |
Positivity for Zinc Transporter 8 Autoantibodies at Diagnosis Is Subsequently Associated With Reduced β-Cell Function and Higher Exogenous Insulin Requirement in Children and Adolescents With Type 1 Diabetes.
This study assessed the relationship between autoantibodies against zinc transporter 8 (ZnT8A) and disease characteristics at diagnosis of type 1 diabetes and during the first 2 years.. Children, younger than 15 years of age (n = 723) who were newly diagnosed with diabetes, were analyzed for ZnT8A, other diabetes-associated autoantibodies, HLA DR-DQ alleles, and metabolic status, which was monitored by pH, plasma glucose, and occurrence of ketoacidosis at diagnosis and through follow-up of C-peptide concentrations, exogenous insulin dose, and glycosylated hemoglobin for 2 years after the diagnosis.. ZnT8A positivity was detected in 530 children (73%). Positivity for ZnT8A was associated with older age (median 8.9 vs. 8.2 years, P = 0.002) and more frequent ketoacidosis (24% vs. 15%, P = 0.013). Children carrying the HLA DR3 allele were less often ZnT8A positive (66% vs. 77%, P = 0.002) than others. ZnT8A-positive children had lower serum C-peptide concentrations (P = 0.008) and higher insulin doses (P = 0.012) over time than their ZnT8A-negative peers.. Positivity for ZnT8A at diagnosis seems to reflect a more aggressive disease process before and after diagnosis. Topics: Adolescent; Alleles; Autoantibodies; C-Peptide; Cation Transport Proteins; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Finland; HLA-DR3 Antigen; Humans; Insulin; Insulin-Secreting Cells; Male; Zinc Transporter 8 | 2016 |
IgG4 subclass glutamic acid decarboxylase antibodies (GADA) are associated with a reduced risk of developing type 1 diabetes as well as increased C-peptide levels in GADA positive gestational diabetes.
Some women with gestational diabetes (GDM) present with autoantibodies associated with type 1 diabetes. These are usually directed against glutamic acid decarboxylase (GADA) and suggested to predict development of type 1 diabetes. The primary aim of this study was to investigate if GADA IgG subclasses at onset of GDM could assist in predicting postpartum development. Of 1225 women diagnosed with first-time GDM only 51 were GADA-positive. Total GADA was determined using ELISA. GADA subclasses were determined with radioimmunoassay. Approximately 25% of GADA-positive women developed type 1 diabetes postpartum. Titers of total GADA were higher in women that developed type 1 diabetes (142.1 vs 74.2u/mL; p=0.04) and they also had lower titers of GADA IgG4 (index=0.01 vs 0.04; p=0.03). In conclusion we found that that women with high titers of total GADA but low titers of GADA IgG4 were more prone to develop type 1 diabetes postpartum. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Glutamate Decarboxylase; Humans; Immunoglobulin G; Pregnancy; Risk Factors | 2016 |
Antibody Response to Serpin B13 Induces Adaptive Changes in Mouse Pancreatic Islets and Slows Down the Decline in the Residual Beta Cell Function in Children with Recent Onset of Type 1 Diabetes Mellitus.
Type 1 diabetes mellitus (T1D) is characterized by a heightened antibody (Ab) response to pancreatic islet self-antigens, which is a biomarker of progressive islet pathology. We recently identified a novel antibody to clade B serpin that reduces islet-associated T cell accumulation and is linked to the delayed onset of T1D. As natural immunity to clade B arises early in life, we hypothesized that it may influence islet development during that time. To test this possibility healthy young Balb/c male mice were injected with serpin B13 mAb or IgG control and examined for the number and cellularity of pancreatic islets by immunofluorescence and FACS. Beta cell proliferation was assessed by measuring nucleotide analog 5-ethynyl-2'-deoxyuridine (5-EdU) incorporation into the DNA and islet Reg gene expression was measured by real time PCR. Human studies involved measuring anti-serpin B13 autoantibodies by Luminex. We found that injecting anti-serpin B13 monoclonal Ab enhanced beta cell proliferation and Reg gene expression, induced the generation of ∼80 pancreatic islets per animal, and ultimately led to increase in the beta cell mass. These findings are relevant to human T1D because our analysis of subjects just diagnosed with T1D revealed an association between baseline anti-serpin activity and slower residual beta cell function decline in the first year after the onset of diabetes. Our findings reveal a new role for the anti-serpin immunological response in promoting adaptive changes in the endocrine pancreas and suggests that enhancement of this response could potentially help impede the progression of T1D in humans. Topics: Animals; Antibodies, Monoclonal; Antibody Formation; Blood Glucose; C-Peptide; Cell Proliferation; Child; Deoxyuridine; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Female; Humans; Immunization, Passive; Insulin-Secreting Cells; Linear Models; Male; Mice, Inbred BALB C; Mice, Inbred NOD; Serpins; Up-Regulation | 2016 |
Transplantation of mesenchymal stem cells improves type 1 diabetes mellitus.
Bone-marrow-derived stem cells can regenerate pancreatic tissue in a model of type 1 diabetes mellitus. Mesenchymal stem cells (MSCs) form the main part of bone marrow. We show that the intrapancreatic transplantation of MSCs elevates serum insulin and C-peptide, while decreasing blood glucose. MSCs engrafted into the damaged rat pancreas become distributed into the blood vessels, acini, ducts, and islets. Renascent islets, islet-like clusters, and a small number of MSCs expressing insulin protein have been observed in the pancreas of diabetic rats. Intrapancreatic transplantation of MSCs triggers a series of molecular and cellular events, including differentiation towards the pancreas directly and the provision of a niche to start endogenous pancreatic regeneration, which ameliorates hypoinsulinemia and hyperglycemia caused by streptozotocin. These data establish the many roles of MSCs in the restoration of the function of an injured organ. Topics: Animals; Blood Glucose; Bone Marrow Cells; C-Peptide; Cell Differentiation; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Hyperglycemia; Insulin; Islets of Langerhans; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Pancreas; Primary Cell Culture; Rats; Rats, Sprague-Dawley; Regeneration | 2016 |
Risk Factors Associated With Severe Hypoglycemia in Older Adults With Type 1 Diabetes.
Severe hypoglycemia is common in older adults with long-standing type 1 diabetes, but little is known about factors associated with its occurrence.. A case-control study was conducted at 18 diabetes centers in the T1D Exchange Clinic Network. Participants were ≥60 years old with type 1 diabetes for ≥20 years. Case subjects (n = 101) had at least one severe hypoglycemic event in the prior 12 months. Control subjects (n = 100), frequency-matched to case subjects by age, had no severe hypoglycemia in the prior 3 years. Data were analyzed for cognitive and functional abilities, social support, depression, hypoglycemia unawareness, various aspects of diabetes management, C-peptide level, glycated hemoglobin level, and blinded continuous glucose monitoring (CGM) metrics.. Glycated hemoglobin (mean 7.8% vs. 7.7%) and CGM-measured mean glucose (175 vs. 175 mg/dL) were similar between case and control subjects. More case than control subjects had hypoglycemia unawareness: only 11% of case subjects compared with 43% of control subjects reported always having symptoms associated with low blood glucose levels (P < 0.001). Case subjects had greater glucose variability than control subjects (P = 0.008) and experienced CGM glucose levels <60 mg/dL for ≥20 min on 46% of days compared with 33% of days in control subjects (P = 0.10). On certain cognitive tests, case subjects scored worse than control subjects.. In older adults with long-standing type 1 diabetes, greater hypoglycemia unawareness and glucose variability are associated with an increased risk of severe hypoglycemia. A study to assess interventions to prevent severe hypoglycemia in high-risk individuals is needed. Topics: Aged; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Male; Middle Aged; Risk Factors | 2016 |
Long-term glycemic control using polymer-encapsulated human stem cell-derived beta cells in immune-competent mice.
The transplantation of glucose-responsive, insulin-producing cells offers the potential for restoring glycemic control in individuals with diabetes. Pancreas transplantation and the infusion of cadaveric islets are currently implemented clinically, but these approaches are limited by the adverse effects of immunosuppressive therapy over the lifetime of the recipient and the limited supply of donor tissue. The latter concern may be addressed by recently described glucose-responsive mature beta cells that are derived from human embryonic stem cells (referred to as SC-β cells), which may represent an unlimited source of human cells for pancreas replacement therapy. Strategies to address the immunosuppression concerns include immunoisolation of insulin-producing cells with porous biomaterials that function as an immune barrier. However, clinical implementation has been challenging because of host immune responses to the implant materials. Here we report the first long-term glycemic correction of a diabetic, immunocompetent animal model using human SC-β cells. SC-β cells were encapsulated with alginate derivatives capable of mitigating foreign-body responses in vivo and implanted into the intraperitoneal space of C57BL/6J mice treated with streptozotocin, which is an animal model for chemically induced type 1 diabetes. These implants induced glycemic correction without any immunosuppression until their removal at 174 d after implantation. Human C-peptide concentrations and in vivo glucose responsiveness demonstrated therapeutically relevant glycemic control. Implants retrieved after 174 d contained viable insulin-producing cells. Topics: Alginates; Animals; Blood Glucose; Blotting, Western; C-Peptide; Cell Culture Techniques; Cell Differentiation; Cell Transplantation; Chromatography, Liquid; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Embryonic Stem Cells; Flow Cytometry; Fluorescent Antibody Technique; Foreign-Body Reaction; Humans; Hydrogels; Immunocompetence; Insulin; Insulin-Secreting Cells; Mice; Microscopy, Confocal; Microscopy, Phase-Contrast; Morpholines; Polymers; Tandem Mass Spectrometry; Triazoles | 2016 |
Successful treatment of young infants presenting neonatal diabetes mellitus with continuous subcutaneous insulin infusion before genetic diagnosis.
Neonatal diabetes mellitus (NDM) is defined as hyperglycemia and impaired insulin secretion with onset within 6 months of birth. While rare, NDM presents complex challenges regarding the management of glycemic control. The availability of continuous subcutaneous insulin infusion pumps (CSII) in combination with continuous glucose monitoring systems (CGM) provides an opportunity to monitor glucose levels more closely and deliver insulin more safely.. We report four cases of young infants with NDM successfully treated with CSII and CGM. Moreover, in two cases with Kir 6.2 mutation, we describe the use of CSII in switching therapy from insulin to sulfonylurea treatment.. Insulin pump requirement for the 4 neonatal diabetes cases was the same regardless of disease pathogenesis and c-peptide levels. No dilution of insulin was needed. The use of an integrated CGM system helped in a more precise control of BG levels with the possibility of several modifications of insulin basal rates. Moreover, as showed in the first two case-reports, when the treatment was switched from insulin to glibenclamide, according to identification of Kir 6.2 mutation and diagnosis of NPDM, the CSII therapy demonstrated to be helpful in allowing gradual insulin suspension and progressive introduction of sulfonylurea.. During the neonatal period, the use of CSII therapy is safe, more physiological, accurate and easier for the insulin administration management. Furthermore, CSII therapy is safe during the switch of therapy from insulin to glibenclamide for infants with permanent neonatal diabetes mellitus. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glyburide; Humans; Hyperglycemia; Infant; Infant, Newborn; Insulin; Insulin Infusion Systems; Male; Monitoring, Physiologic; Sulfonylurea Compounds | 2016 |
Diabetes: Encapsulated β-cell implants enable glycaemic control.
Topics: Alginates; Animals; Blood Glucose; C-Peptide; Cell Transplantation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Foreign-Body Reaction; Humans; Hydrogels; Insulin-Secreting Cells | 2016 |
Human islets and dendritic cells generate post-translationally modified islet autoantigens.
The initiation of type 1 diabetes (T1D) requires a break in peripheral tolerance. New insights into neoepitope formation indicate that post-translational modification of islet autoantigens, for example via deamidation, may be an important component of disease initiation or exacerbation. Indeed, deamidation of islet autoantigens increases their binding affinity to the T1D highest-risk human leucocyte antigen (HLA) haplotypes HLA-DR3/DQ2 and -DR4/DQ8, increasing the chance that T cells reactive to deamidated autoantigens can be activated upon T cell receptor ligation. Here we investigated human pancreatic islets and inflammatory and tolerogenic human dendritic cells (DC and tolDC) as potential sources of deamidated islet autoantigens and examined whether deamidation is altered in an inflammatory environment. Islets, DC and tolDC contained tissue transglutaminase, the key enzyme responsible for peptide deamidation, and enzyme activity increased following an inflammatory insult. Islets treated with inflammatory cytokines were found to contain deamidated insulin C-peptide. DC, heterozygous for the T1D highest-risk DQ2/8, pulsed with native islet autoantigens could present naturally processed deamidated neoepitopes. HLA-DQ2 or -DQ8 homozygous DC did not present deamidated islet peptides. This study identifies both human islets and DC as sources of deamidated islet autoantigens and implicates inflammatory activation of tissue transglutaminase as a potential mechanism for islet and DC deamidation. Topics: Amides; Autoantigens; C-Peptide; Dendritic Cells; Diabetes Mellitus, Type 1; HLA-DQ Antigens; HLA-DR3 Antigen; Humans; Immune Tolerance; Inflammation; Islets of Langerhans; Protein Processing, Post-Translational; Proteome; T-Lymphocytes; Transglutaminases | 2016 |
Pathogenic CD4 T cells in type 1 diabetes recognize epitopes formed by peptide fusion.
T cell-mediated destruction of insulin-producing β cells in the pancreas causes type 1 diabetes (T1D). CD4 T cell responses play a central role in β cell destruction, but the identity of the epitopes recognized by pathogenic CD4 T cells remains unknown. We found that diabetes-inducing CD4 T cell clones isolated from nonobese diabetic mice recognize epitopes formed by covalent cross-linking of proinsulin peptides to other peptides present in β cell secretory granules. These hybrid insulin peptides (HIPs) are antigenic for CD4 T cells and can be detected by mass spectrometry in β cells. CD4 T cells from the residual pancreatic islets of two organ donors who had T1D also recognize HIPs. Autoreactive T cells targeting hybrid peptides may explain how immune tolerance is broken in T1D. Topics: Amino Acid Sequence; Animals; C-Peptide; CD4-Positive T-Lymphocytes; Clone Cells; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Epitopes; Immune Tolerance; Insulin-Secreting Cells; Mice; Mice, Inbred NOD; Molecular Sequence Data; Peptides | 2016 |
Rapid Normalization of High Glutamic Acid Decarboxylase Autoantibody Titers and Preserved Endogenous Insulin Secretion in a Patient with Diabetes Mellitus: A Case Report and Literature Review.
A 59-year-old Japanese woman developed diabetes mellitus without ketoacidosis in the presence of glutamic acid decarboxylase autoantibody (GADA) (24.7 U/mL). After the amelioration of her hyperglycemia, the patient had a relatively preserved serum C-peptide level. Her endogenous insulin secretion capacity remained almost unchanged during 5 years of insulin therapy. The patient's GADA titers normalized within 15 months. The islet-related autoantibodies, including GADA, are believed to be produced following the autoimmune destruction of pancreatic beta cells and are predictive markers of type 1 diabetes mellitus. Therefore, the transient appearance of GADA in our patient may have reflected pancreatic autoimmune processes that terminated without progression to insulin deficiency. Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Female; Glutamate Decarboxylase; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin Secretion; Middle Aged; Pancreas; Predictive Value of Tests; Treatment Outcome | 2016 |
Immunological Aspects of Fulminant Type 1 Diabetes in Chinese.
Background. Fulminant type 1 diabetes (FT1D) is a novel subtype of type 1 diabetes characterized by extremely rapid onset and complete deficiency of insulin due to the destruction of pancreatic β cells. However, the precise mechanisms underlying the etiology of this disease remain unclear. Methods. A total of 22 patients with FT1D and 10 healthy subjects were recruited. Serum antibodies to GAD, IA2, and ZnT8 in patients were tested. And peripheral T cell responses to GAD65, insulin B9-23 peptide, or C peptide were determined in 10 FT1D patients and 10 healthy controls. The mRNA levels of several related cytokines and molecules, such as IFN-γ, IL-4, RORC, and IL-17 in PBMCs from FT1D patients were analyzed by qRT-PCR. Result. We found that a certain proportion of Chinese FT1D patients actually have developed islet-related autoantibodies after onset of the disease. The GAD, insulin, or C peptide-reactive T cells were found in some FT1D patients. We also detected a significant increase for IFN-γ expression in FT1D PBMCs as compared with that of healthy controls. Conclusion. Autoimmune responses might be involved in the pathogenesis of Chinese FT1D. Topics: Adult; Asian People; Autoantibodies; Autoimmunity; C-Peptide; Cation Transport Proteins; Cytokines; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Insulin-Secreting Cells; Interferon-gamma; Interleukin-17; Interleukin-4; Islets of Langerhans; Leukocytes, Mononuclear; Male; T-Lymphocytes; Young Adult; Zinc Transporter 8 | 2016 |
A model-based approach to sample size estimation in recent onset type 1 diabetes.
The area under the curve C-peptide following a 2-h mixed meal tolerance test from 498 individuals enrolled on five prior TrialNet studies of recent onset type 1 diabetes from baseline to 12 months after enrolment were modelled to produce estimates of its rate of loss and variance.. Age at diagnosis and baseline C-peptide were found to be significant predictors, and adjusting for these in an ANCOVA resulted in estimates with lower variance.. Using these results as planning parameters for new studies results in a nearly 50% reduction in the target sample size. The modelling also produces an expected C-peptide that can be used in observed versus expected calculations to estimate the presumption of benefit in ongoing trials. Copyright © 2016 John Wiley & Sons, Ltd. Topics: Adolescent; Adult; Age of Onset; Area Under Curve; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Male; Middle Aged; Models, Statistical; Prognosis; Sample Size; Young Adult | 2016 |
Validation of the BETA-2 Score: An Improved Tool to Estimate Beta Cell Function After Clinical Islet Transplantation Using a Single Fasting Blood Sample.
The beta score, a composite measure of beta cell function after islet transplantation, has limited sensitivity because of its categorical nature and requires a mixed-meal tolerance test (MMTT). We developed a novel score based on a single fasting blood sample. The BETA-2 score used stepwise forward linear regression incorporating glucose (in millimoles per liter), C-peptide (in nanomoles per liter), hemoglobin A1c (as a percentage) and insulin dose (U/kg per day) as continuous variables from the original beta score data set (n = 183 MMTTs). Primary and secondary analyses assessed the score's ability to detect glucose intolerance (90-min MMTT glucose ≥8 mmol/L) and insulin independence, respectively. A validation cohort of islet transplant recipients (n = 114 MMTTs) examined 12 mo after transplantation was used to compare the score's ability to detect these outcomes. The BETA-2 score was expressed as follows (range 0-42): [Formula: see text] A score <20 and ≥15 detected glucose intolerance and insulin independence, respectively, with >82% sensitivity and specificity. The BETA-2 score demonstrated greater discrimination than the beta score for these outcomes (p < 0.05). Using a fasting blood sample, the BETA-2 score estimates graft function as a continuous variable and shows greater discrimination of glucose intolerance and insulin independence after transplantation versus the beta score, allowing frequent assessments of graft function. Studies examining its utility to track long-term graft function are required. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Fasting; Female; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Graft Survival; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Prognosis; Severity of Illness Index | 2016 |
Practical Classification Guidelines for Diabetes in patients treated with insulin: a cross-sectional study of the accuracy of diabetes diagnosis.
Differentiating between type 1 and type 2 diabetes is fundamental to ensuring appropriate management of patients, but can be challenging, especially when treating with insulin. The 2010 UK Practical Classification Guidelines for Diabetes were developed to help make the differentiation.. To assess diagnostic accuracy of the UK guidelines against 'gold standard' definitions of type 1 and type 2 diabetes based on measured C-peptide levels.. In total, 601 adults with insulin-treated diabetes and diabetes duration ≥5 years were recruited in Devon, Northamptonshire, and Leicestershire.. Baseline information and home urine sample were collected. Urinary C-peptide creatinine ratio (UCPCR) measures endogenous insulin production. Gold standard type 1 diabetes was defined as continuous insulin treatment within 3 years of diagnosis and absolute insulin deficiency (UCPCR<0.2 nmol/mmol ≥5 years post-diagnosis); all others classed as having type 2 diabetes. Diagnostic performance of the clinical criteria was assessed and other criteria explored using receiver operating characteristic (ROC) curves.. UK guidelines correctly classified 86% of participants. Most misclassifications occurred in patients classed as having type 1 diabetes who had significant endogenous insulin levels (57 out of 601; 9%); most in those diagnosed ≥35 years and treated with insulin from diagnosis, where 37 out of 66 (56%) were misclassified. Time to insulin and age at diagnosis performed best in predicting long-term endogenous insulin production (ROC AUC = 0.904 and 0.871); BMI was a less strong predictor of diabetes type (AUC = 0.824).. Current UK guidelines provide a pragmatic clinical approach to classification reflecting long-term endogenous insulin production; caution is needed in older patients commencing insulin from diagnosis, where misclassification rates are increased. Topics: Biomarkers; Body Mass Index; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Practice Guidelines as Topic; Reproducibility of Results; ROC Curve; United Kingdom | 2016 |
A pilot study showing associations between frequency of CD4(+) memory cell subsets at diagnosis and duration of partial remission in type 1 diabetes.
In some patients with type 1 diabetes the dose of insulin required to achieve euglycemia is substantially reduced soon after diagnosis. This partial remission is associated with β-cell function and good glucose control. The purpose of this study was to assess whether frequencies of CD4(+) T cell subsets in children newly diagnosed with type 1 diabetes are associated with length of partial remission. We found that the frequency of CD4(+) memory cells, activated Treg cells and CD25(+) cells that express a high density of the IL-7 receptor, CD127 (CD127(hi)) are strongly associated with length of partial remission. Prediction of length of remission via Cox regression is significantly enhanced when CD25(+) CD127(hi) cell frequency is combined with either Insulin Dependent Adjusted A1c (IDAA1c), or glycosylated hemoglobin (HbA1c), or C-peptide levels at diagnosis. CD25(+) CD127(hi) cells do not express Foxp3, LAG-3 and CD49b, indicating that they are neither Treg nor Tr1 cells. Topics: Adolescent; C-Peptide; CD4-Positive T-Lymphocytes; Child; Diabetes Mellitus, Type 1; Female; Flow Cytometry; Forkhead Transcription Factors; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunologic Memory; Insulin; Integrin alpha2; Interleukin-2 Receptor alpha Subunit; Interleukin-7 Receptor alpha Subunit; Male; Pilot Projects; Remission Induction; T-Lymphocyte Subsets; T-Lymphocytes, Regulatory; Time Factors | 2016 |
Reproducible preparation of spheroids of pancreatic hormone positive cells from human iPS cells: An in vitro study.
Transplantation of islets of Langerhans is regarded as a promising therapy for type 1 diabetes. A large number of β-cells are required for the treatment of human type 1 diabetes. Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem cells, have been considered as new sources for cell replacement therapy.. Cell aggregates were prepared from human iPS cells using agarose microwell plates and differentiated into pancreatic endocrine cells by changing the culture media with different additives.. After 20days of culture, approximately 30% of cells in aggregates were positive for C-peptide. After another 14days in culture, the cells gained an ability to alter C-peptide release in response to changes in the glucose concentration.. Uniform aggregates of human iPSCs were easily prepared on agarose microwell plates and efficiently differentiated into the pancreatic endocrine lineage. Thus, aggregate culture is a suitable method for preparing islet-like aggregates from human iPSCs.. Our results indicate that the microwell plate is suitable for scaling up the preparation of pancreatic endocrine cells from human iPS cells in a robotic system. Topics: C-Peptide; Cell Differentiation; Cell Lineage; Cells, Cultured; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Endocrine Cells; Glucose; Humans; Induced Pluripotent Stem Cells; Insulin; Insulin-Secreting Cells; Pancreatic Hormones; Pluripotent Stem Cells | 2016 |
HLA-A*24 Carrier Status and Autoantibody Surges Posttransplantation Associate With Poor Functional Outcome in Recipients of an Islet Allograft.
We investigated whether changes in islet autoantibody profile and presence of HLA risk markers, reported to predict rapid β-cell loss in pre-type 1 diabetes, associate with poor functional outcome in islet allograft recipients.. Forty-one patients received ≥2.3 million β-cells/kg body wt in one to two intraportal implantations. Outcome after 6-18 months was assessed by C-peptide (random and stimulated), insulin dose, and HbA1c.. Patients carrying HLA-A*24-positive or experiencing a significant autoantibody surge within 6 months after the first transplantation (n = 19) had lower C-peptide levels (P ≤ 0.003) and higher insulin needs (P < 0.001) despite higher HbA1c levels (P ≤ 0.018). They became less often insulin independent (16% vs. 68%, P = 0.002) and remained less often C-peptide positive (47% vs. 100%, P < 0.001) than recipients lacking both risk factors. HLA-A*24 positivity or an autoantibody surge predicted insulin dependence (P = 0.007).. HLA-A*24 and early autoantibody surge after islet implantation associate with poor functional graft outcome. Topics: Adult; Allografts; Autoantibodies; C-Peptide; Cation Transport Proteins; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; HLA-A24 Antigen; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Transplantation, Homologous; Treatment Outcome; Zinc Transporter 8 | 2016 |
Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes-A Recursive Partitioning Analysis.
To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes.. Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clinical characteristics, including genotype, antibody titers, and metabolic markers were analyzed.. Age and GAD65 autoantibody (GAD65Ab) titers defined three risk classes for progression from single to multiple autoantibodies. The 5-year risk was 11% for those subjects >16 years of age with low GAD65Ab titers, 29% for those ≤16 years of age with low GAD65Ab titers, and 45% for those subjects with high GAD65Ab titers regardless of age. Progression to dysglycemia was associated with islet antigen 2 Ab titers, and 2-h glucose and fasting C-peptide levels. The 5-year risk is 28%, 39%, and 51% for respective risk classes defined by the three predictors. Progression to type 1 diabetes was associated with the number of positive autoantibodies, peak C-peptide level, HbA1c level, and age. Four risk classes defined by RPA had a 5-year risk of 9%, 33%, 62%, and 80%, respectively.. The use of RPA offered a new classification approach that could predict the timing of transitions from one preclinical stage to the next in the development of type 1 diabetes. Using these RPA classes, new prevention techniques can be tailored based on the individual prognostic risk characteristics at different preclinical stages. Topics: Adolescent; Adult; Age Factors; Autoantibodies; C-Peptide; Cation Transport Proteins; Child; Cohort Studies; Diabetes Mellitus, Type 1; Disease Progression; Female; Genotype; Glucose Metabolism Disorders; Glutamate Decarboxylase; HLA-DQ alpha-Chains; HLA-DQ beta-Chains; Humans; Insulin; Male; Multivariate Analysis; Prognosis; Prospective Studies; Risk; Young Adult; Zinc Transporter 8 | 2016 |
The heterogeneity of islet autoantibodies and the progression of islet failure in type 1 diabetic patients.
Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobinA1c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1DM patients (duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus. Topics: Adolescent; Adult; Asian People; Autoantibodies; Body Mass Index; C-Peptide; Cation Transport Proteins; China; Diabetes Mellitus, Type 1; Disease Progression; Enzyme-Linked Immunosorbent Assay; Female; Glutamate Decarboxylase; Humans; Insulin; Islets of Langerhans; Logistic Models; Male; Middle Aged; Radioimmunoassay; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Risk Factors; Young Adult; Zinc Transporter 8 | 2016 |
Clinical characteristics of patients aged 65 and older with newly developed type 1 diabetes: An analysis of elderly patients at our hospital.
We herein investigated the clinical features of elderly patients with newly developed type 1 diabetes with respect to onset age, frequency of islet-associated antibodies, and other clinical markers.. One hundred and ninety-nine patients aged 65 and older with new-onset diabetes, who were admitted to our hospital between July 2000 and June 2013, were classified into 4 types of diabetes. In addition, 85 patients with newly diagnosed type 1A diabetes among all age ranges admitted during the same period were divided into two groups: a younger group (less than 65 years, n=71) and an elderly group (65 years and older, n=14). Clinical features including mode of onset, frequency of islet-associated antibodies, and serum C-peptide (CPR) levels were compared between these groups. The elderly group was further divided into two age groups (less than 75 years, n=7; 75 years and older, n=7), and the frequency of autoantibodies was compared.. The patients (n=199) were classified into type 1 (n=16, 8%), type 2 (n=155, 78%), pancreatic (n=22, 11%), and other type (n=6, 3%) diabetes. Between the younger and elderly groups with type 1 diabetes, no significant difference in the CPR levels, frequency of autoantibodies, or other clinical features were observed. Positivity for IA-2 antibody was higher in the younger group (53.5%) than in the elderly group (35.7%), however, it was also considerably high (57.1%) in the oldest age group (75 years and older).. Type 1 diabetes may develop in the elderly, and an IA-2 antibody test may be useful for diagnosing type 1 diabetes in older patients. Topics: Age of Onset; Aged; Aged, 80 and over; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Male | 2016 |
Systematic Population Screening, Using Biomarkers and Genetic Testing, Identifies 2.5% of the U.K. Pediatric Diabetes Population With Monogenic Diabetes.
Monogenic diabetes is rare but is an important diagnosis in pediatric diabetes clinics. These patients are often not identified as this relies on the recognition of key clinical features by an alert clinician. Biomarkers (islet autoantibodies and C-peptide) can assist in the exclusion of patients with type 1 diabetes and allow systematic testing that does not rely on clinical recognition. Our study aimed to establish the prevalence of monogenic diabetes in U.K. pediatric clinics using a systematic approach of biomarker screening and targeted genetic testing.. We studied 808 patients (79.5% of the eligible population) <20 years of age with diabetes who were attending six pediatric clinics in South West England and Tayside, Scotland. Endogenous insulin production was measured using the urinary C-peptide creatinine ratio (UCPCR). C-peptide-positive patients (UCPCR ≥0.2 nmol/mmol) underwent islet autoantibody (GAD and IA2) testing, with patients who were autoantibody negative undergoing genetic testing for all 29 identified causes of monogenic diabetes.. A total of 2.5% of patients (20 of 808 patients) (95% CI 1.6-3.9%) had monogenic diabetes (8 GCK, 5 HNF1A, 4 HNF4A, 1 HNF1B, 1 ABCC8, 1 INSR). The majority (17 of 20 patients) were managed without insulin treatment. A similar proportion of the population had type 2 diabetes (3.3%, 27 of 808 patients).. This large systematic study confirms a prevalence of 2.5% of patients with monogenic diabetes who were <20 years of age in six U.K. clinics. This figure suggests that ∼50% of the estimated 875 U.K. pediatric patients with monogenic diabetes have still not received a genetic diagnosis. This biomarker screening pathway is a practical approach that can be used to identify pediatric patients who are most appropriate for genetic testing. Topics: Adolescent; Antigens, CD; Autoantibodies; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; England; Female; Genetic Testing; Germinal Center Kinases; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 1-beta; Hepatocyte Nuclear Factor 4; Humans; Infant; Male; Prevalence; Protein Serine-Threonine Kinases; Receptor, Insulin; Scotland; Sequence Analysis, DNA; Sulfonylurea Receptors; Young Adult | 2016 |
Increased circulating concentrations of mesencephalic astrocyte-derived neurotrophic factor in children with type 1 diabetes.
Mesencephalic astrocyte-derived neurotrophic factor (MANF) was recently shown to be essential for the survival and proliferation of pancreatic β-cells in mice, where deletion of MANF resulted in diabetes. The current study aimed at determining whether the concentration of circulating MANF is associated with the clinical manifestation of human type 1 diabetes (T1D). MANF expression in T1D or MANF levels in serum have not been previously studied. We developed an enzyme-linked immunosorbent assay (ELISA) for MANF and measured serum MANF concentrations from 186 newly diagnosed children and adolescents and 20 adults with longer-term T1D alongside with age-matched controls. In healthy controls the mean serum MANF concentration was 7.0 ng/ml. High MANF concentrations were found in children 1-9 years of age close to the diagnosis of T1D. The increased MANF concentrations were not associated with diabetes-predictive autoantibodies and autoantibodies against MANF were extremely rare. Patients with conspicuously high MANF serum concentrations had lower C-peptide levels compared to patients with moderate MANF concentrations. Our data indicate that increased MANF concentrations in serum are associated with the clinical manifestation of T1D in children, but the exact mechanism behind the increase remains elusive. Topics: Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression Regulation; Humans; Infant; Insulin-Secreting Cells; Male; Nerve Growth Factors; Neurons | 2016 |
A Cross-sectional Study to Assess the Prevalence of Pancreatic Exocrine Insufficiency Among Diabetes Mellitus Patients in Turkey.
Topics: Adult; Aged; Aged, 80 and over; Alanine Transaminase; Amylases; C-Peptide; Comorbidity; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Exocrine Pancreatic Insufficiency; Female; Gastrointestinal Diseases; Humans; Male; Middle Aged; Prevalence; Turkey; Young Adult | 2016 |
Fall in C-Peptide During First 4 Years From Diagnosis of Type 1 Diabetes: Variable Relation to Age, HbA1c, and Insulin Dose.
We aimed to describe the natural history of residual insulin secretion in Type 1 Diabetes TrialNet participants over 4 years from diagnosis and relate this to previously reported alternative clinical measures reflecting β-cell secretory function.. Data from 407 subjects from 5 TrialNet intervention studies were analyzed. All subjects had baseline stimulated C-peptide values of ≥0.2 nmol/L from mixed-meal tolerance tests (MMTTs). During semiannual visits, C-peptide values from MMTTs, HbA1c, and insulin doses were obtained.. The percentage of individuals with stimulated C-peptide of ≥0.2 nmol/L or detectable C-peptide of ≥0.017 nmol/L continued to diminish over 4 years; this was markedly influenced by age. At 4 years, only 5% maintained their baseline C-peptide secretion. The expected inverse relationships between C-peptide and HbA1c or insulin doses varied over time and with age. Combined clinical variables, such as insulin-dose adjusted HbA1c (IDAA1C) and the relationship of IDAA1C to C-peptide, also were influenced by age and time from diagnosis. Models using these clinical measures did not fully predict C-peptide responses. IDAA1C ≤9 underestimated the number of individuals with stimulated C-peptide ≥0.2 nmol/L, especially in children.. Current trials of disease-modifying therapy for type 1 diabetes should continue to use C-peptide as a primary end point of β-cell secretory function. Longer duration of follow-up is likely to provide stronger evidence of the effect of disease-modifying therapy on preservation of β-cell function. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Randomized Controlled Trials as Topic; Time Factors; Young Adult | 2016 |
Do Electrochemiluminescence Assays Improve Prediction of Time to Type 1 Diabetes in Autoantibody-Positive TrialNet Subjects?
To explore whether electrochemiluminescence (ECL) assays can help improve prediction of time to type 1 diabetes in the TrialNet autoantibody-positive population.. TrialNet subjects who were positive for one or more autoantibodies (microinsulin autoantibody, GAD65 autoantibody [GADA], IA-2A, and ZnT8A) with available ECL-insulin autoantibody (IAA) and ECL-GADA data at their initial visit were analyzed; after a median follow-up of 24 months, 177 of these 1,287 subjects developed diabetes.. Univariate analyses showed that autoantibodies by radioimmunoassays (RIAs), ECL-IAA, ECL-GADA, age, sex, number of positive autoantibodies, presence of HLA DR3/4-DQ8 genotype, HbA1c, and oral glucose tolerance test (OGTT) measurements were all significantly associated with progression to diabetes. Subjects who were ECL positive had a risk of progression to diabetes within 6 years of 58% compared with 5% for the ECL-negative subjects (P < 0.0001). Multivariate Cox proportional hazards models were compared, with the base model including age, sex, OGTT measurements, and number of positive autoantibodies by RIAs. The model with positivity for ECL-GADA and/or ECL-IAA was the best, and factors that remained significantly associated with time to diabetes were area under the curve (AUC) C-peptide, fasting C-peptide, AUC glucose, number of positive autoantibodies by RIAs, and ECL positivity. Adding ECL to the Diabetes Prevention Trial risk score (DPTRS) improved the receiver operating characteristic curves with AUC of 0.83 (P < 0.0001).. ECL assays improved the ability to predict time to diabetes in these autoantibody-positive relatives at risk for developing diabetes. These findings might be helpful in the design and eligibility criteria for prevention trials in the future. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease Progression; Female; Glycated Hemoglobin; Humans; Insulin Antibodies; Longitudinal Studies; Luminescence; Male; Proportional Hazards Models; Prospective Studies; Risk Factors; Time Factors; Young Adult | 2016 |
Combination high-dose omega-3 fatty acids and high-dose cholecalciferol in new onset type 1 diabetes: a potential role in preservation of beta-cell mass.
Several studies have evaluated the role of inflammation in type 1 diabetes (T1D). The safety profile and anti-inflammatory properties of high dose omega-3 fatty acids combined with Vitamin D supplementation make this therapy a possible candidate for T1D intervention trials. Herein, we describe the case of a 14-year-old boy with new onset T1D treated with high dose Omega-3 and vitamin D3. By 12 months, peak C-peptide increased to 0.55 nmol/L (1.66 ng/mL) corresponding to a 20% increment from baseline and AUC C-peptide was slightly higher compared to 9 months (0.33 vs. 0.30 nmol/L/min) although remaining slightly lower than baseline. Combination high-dose Omega-3 fatty acids and high-dose vitamin D3 therapy was well tolerated and may have beneficial effects on beta-cell function. Randomized controlled trials could be of assistance to determine whether this therapy may result in the preservation of beta-cell function in patients with new onset T1D. Topics: Adolescent; B-Lymphocytes; C-Peptide; Cholecalciferol; Diabetes Mellitus, Type 1; Dietary Supplements; Dose-Response Relationship, Drug; Drug Therapy, Combination; Fatty Acids, Omega-3; Humans; Hypoglycemic Agents; Immunity, Cellular; Male; Treatment Outcome | 2016 |
Sustained Islet Allograft Function After Peritransplant Treatment Using Exenatide With and Without Everolimus.
Topics: Allografts; C-Peptide; Diabetes Mellitus, Type 1; Everolimus; Exenatide; Glycated Hemoglobin; Graft Survival; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Islets of Langerhans Transplantation; Peptides; Pilot Projects; Time Factors; Treatment Outcome; Venoms | 2016 |
Beta cell function and ongoing autoimmunity in long-standing, childhood onset type 1 diabetes.
This study aimed to determine the frequency of residual beta cell function in individuals with long-standing type 1 diabetes who were recruited at diagnosis, and relate this to baseline and current islet autoantibody profile.. Two hour post-meal urine C-peptide:creatinine ratio (UCPCR) and islet autoantibodies were measured in samples collected from 144 participants (median age at diagnosis: 11.7 years; 47% male), a median of 23 years (range 12-29 years) after diagnosis. UCPCR thresholds equivalent to mixed meal-stimulated serum C-peptide >0.001 nmol/l, ≥0.03 nmol/l and ≥0.2 nmol/l were used to define 'detectable', 'minimal' and 'residual/preserved') endogenous insulin secretion, respectively. Autoantibodies against GAD (GADA), islet antigen-2 (IA-2A), zinc transporter 8 (ZnT8A) and insulin (IAA) were measured by radioimmunoassay.. Endogenous C-peptide secretion was detectable in 51 participants (35.4%), including residual secretion in seven individuals (4.9%) and minimal secretion in 14 individuals (9.7%). In the 132 samples collected more than 10 years after diagnosis, 86 participants (65.2%) had at least one islet autoantibody: 42 (31.8%) were positive for GADA, 69 (52.3%) for IA-2A and 14 of 104 tested were positive for ZnT8A (13.5%). The level of UCPCR was related to age at diagnosis (p = 0.002) and was independent of diabetes duration, and baseline or current islet autoantibody status.. There is evidence of ongoing autoimmunity in the majority of individuals with longstanding diabetes. Endogenous insulin secretion continues for many years after diagnosis in individuals diagnosed with autoimmune-mediated type 1 diabetes above age 5. These findings suggest that some beta cells are protected from continued autoimmune attack in longstanding type 1 diabetes. Topics: Adolescent; Adult; Autoantibodies; Autoimmunity; C-Peptide; Child; Creatine; Diabetes Mellitus, Type 1; Genotype; Histocompatibility Antigens Class II; Humans; Insulin-Secreting Cells; Radioimmunoassay; Young Adult | 2016 |
Long-Term Prediction of Severe Hypoglycemia in Type 1 Diabetes: Is It Really Possible?
Prediction of risk of severe hypoglycemia (SH) in patients with type 1 diabetes is important to prevent future episodes, but it is unknown if it is possible to predict the long-term risk of SH. The aim of the study is to assess if long-term prediction of SH is possible in type 1 diabetes.. A follow-up study was performed with 98 patients with type 1 diabetes. At baseline and at follow-up, the patients filled in a questionnaire about diabetes history and complications, number of SH in the preceding year and state of awareness, and HbA1c and C-peptide levels were measured.. During the 12 years of follow-up, there was a decrease in HbA1c, C-peptide levels, and incidence of SH (1.1 to 0.4 episodes per patient-year; P < .001). At baseline, the relative rate of SH was 3.6 (P = .001) and 10.9 (P < .0001) in patients with impaired awareness and unawareness of hypoglycemia, respectively, as compared to patients with normal awareness. At follow-up, patients with unawareness at baseline tended to have maintained an increased rate of SH (RR = 3.1; P = .07). Impaired awareness, HbA1c and C-peptide determined at baseline did not correspond with an increased rate of SH at follow-up.. Long-term prediction of severe hypoglycemia in type 1 diabetes was not possible, although baseline hypoglycemia unawareness tended to remain a predictor for risk of SH at follow-up. Therefore, it is important repeatedly to assess the different risk factors of SH to determine the actual risk. Topics: Adult; Aged; C-Peptide; Cross-Sectional Studies; Diabetes Complications; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; History, 17th Century; Humans; Hypoglycemia; Hypoglycemic Agents; Incidence; Insulin; Male; Middle Aged; Risk Factors | 2016 |
Infusion with Human Bone Marrow-derived Mesenchymal Stem Cells Improves β-cell Function in Patients and Non-obese Mice with Severe Diabetes.
Mesenchymal stem cells (MSCs) transplantation is a promising therapeutic strategy for type 1 diabetes (T1D). However, little is known on whether MSC transplantation can benefit T1D patients with ketoacidosis and its potential actions. Here, we show that infusion with bone marrow MSCs preserves β-cell function in some T1D patients with ketoacidosis by decreasing exogenous insulin requirement and increasing plasma C-peptide levels up to 1-2 years. MSC transplantation increased plasma and islet insulin contents in non-obese diabetic (NOD) mice with severe diabetes. In comparison with severe diabetes controls, MSC infusion reduced insulitis, decreased pancreatic TNF-α, and increased IL-10 and TGF-β1 expression in NOD mice. MSC infusion increased the percentages of splenic Tregs and levels of plasma IL-4, IL-10 and TGF-β1, but reduced the percentages of splenic CD8 Topics: Adolescent; Adult; Animals; B-Lymphocytes; Bone Marrow Cells; C-Peptide; CD8-Positive T-Lymphocytes; Cytokines; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Female; Humans; Inflammation; Insulin-Secreting Cells; Interleukin-10; Ketosis; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Pancreas; Spleen; T-Lymphocytes, Regulatory; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha; Young Adult | 2016 |
Prediction of Impending Type 1 Diabetes through Automated Dual-Label Measurement of Proinsulin:C-Peptide Ratio.
The hyperglycemic clamp test, the gold standard of beta cell function, predicts impending type 1 diabetes in islet autoantibody-positive individuals, but the latter may benefit from less invasive function tests such as the proinsulin:C-peptide ratio (PI:C). The present study aims to optimize precision of PI:C measurements by automating a dual-label trefoil-type time-resolved fluorescence immunoassay (TT-TRFIA), and to compare its diagnostic performance for predicting type 1 diabetes with that of clamp-derived C-peptide release.. Between-day imprecision (n = 20) and split-sample analysis (n = 95) were used to compare TT-TRFIA (AutoDelfia, Perkin-Elmer) with separate methods for proinsulin (in-house TRFIA) and C-peptide (Elecsys, Roche). High-risk multiple autoantibody-positive first-degree relatives (n = 49; age 5-39) were tested for fasting PI:C, HOMA2-IR and hyperglycemic clamp and followed for 20-57 months (interquartile range).. TT-TRFIA values for proinsulin, C-peptide and PI:C correlated significantly (r2 = 0.96-0.99; P<0.001) with results obtained with separate methods. TT-TRFIA achieved better between-day %CV for PI:C at three different levels (4.5-7.1 vs 6.7-9.5 for separate methods). In high-risk relatives fasting PI:C was significantly and inversely correlated (rs = -0.596; P<0.001) with first-phase C-peptide release during clamp (also with second phase release, only available for age 12-39 years; n = 31), but only after normalization for HOMA2-IR. In ROC- and Cox regression analysis, HOMA2-IR-corrected PI:C predicted 2-year progression to diabetes equally well as clamp-derived C-peptide release.. The reproducibility of PI:C benefits from the automated simultaneous determination of both hormones. HOMA2-IR-corrected PI:C may serve as a minimally invasive alternative to the more tedious hyperglycemic clamp test. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fasting; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hyperglycemia; Insulin; Insulin Resistance; Insulin-Secreting Cells; Male; Prognosis; Proinsulin; Regression Analysis | 2016 |
Clinical Characteristics of 261 Cases of Hospitalized Patients with Type 1 Diabetes Mellitus.
Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; Young Adult | 2016 |
First test effect in intravenous glucose tolerance testing.
Intravenous glucose tolerance testing (IVGTT) is a common test of β-cell function in which a glucose load is administered and insulin and/or C-peptide responses are monitored. Since the first IVGTT may be more stressful and stress may alter β-cell secretion or hepatic insulin extraction, we asked whether there was a first test effect.. Insulin and C-peptide responses were compared from two sequential IVGTTs performed within 6 months during staging for the Diabetes Prevention Trial-Type 1 (DPT-1) in 368 people at high risk for type 1 diabetes. Insulin data (1+3 min) were used because the first phase insulin response (and peak insulin concentration) occurs within this time frame. Areas under the curve (AUC) calculations represent early insulin or C-peptide responses from 0 through 10 min post-glucose challenge.. More than half of all subjects were found to have first test values lower than the second. This was true for all measures of both insulin and C-peptide but the frequency was significantly different only for insulin measures corrected for basal and for insulin AUC (p < 0.05). However, for subjects (n = 99) whose 1+3 min insulin response was <10th percentile on the first test, there was a significant increase on the second test (p < 0.05). The C-peptide: insulin ratio did not change significantly between tests, indicating that differences are due to changes in β-cell secretion rather than hepatic insulin uptake.. A statistically significant first test effect occurs during the IVGTT attributable to variations in insulin secretion rather than hepatic uptake. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Family Health; Glucose; Glucose Intolerance; Glucose Tolerance Test; Humans; Infusions, Intravenous; Insulin; Insulin Secretion; Insulin-Secreting Cells; Liver; Middle Aged; Reproducibility of Results; Risk; Stress, Psychological; Young Adult | 2015 |
Effect and mechanisms of human Wharton's jelly-derived mesenchymal stem cells on type 1 diabetes in NOD model.
Type 1 diabetes is an autoimmune disease that results from an inflammatory destruction of β-cells in islets. Mesenchymal stem cells derived from Wharton's jelly (WJ-MSCs) own a peculiar immunomodulatory feature and might reverse the inflammatory destruction and repair the function of β-cells. Sixty NOD mice were divided into four groups, including normal control group, WJ-MSCs prevention group (before onset), WJ-MSCs treatment group (after onset), and diabetic control group. After homologous therapy, onset time of diabetes, levels of fasting plasma glucose (FPG), fed blood glucose and C-peptide, regulation of cytokines, and islet cells were examined and evaluated. After WJ-MSCs infusion, FPG and fed blood glucose in WJ-MSCs treatment group decreased to normal level in 6-8 days and maintained for 6 weeks. Level of fasting C-peptide of these mice was higher compared to diabetic control mice (P=0.027). In WJ-MSCs prevention group, WJ-MSCs played a protective role for 8-week delayed onset of diabetes, and fasting C-peptide in this group was higher compared to the other two diabetic groups (P=0.013, 0.035). Compared with diabetic control group, frequencies of CD4+CD25+Foxp3+ Tregs in WJ-MSCs prevention group and treatment group were higher, while levels of IL-2, IFN-γ, and TNF-α were lower (P<0.001); the degree of insulitis was also depressed, especially for WJ-MSCs prevention group (P<0.05). Infusion of WJ-MSCs could aid in T1DM through regulation of the autoimmunity and recovery of islet β-cells no matter before or after onset of T1DM. WJ-MSCs might be an effective method for T1DM. Topics: Animals; Blood Glucose; C-Peptide; Cell Differentiation; Cytokines; Diabetes Mellitus, Type 1; Female; Islets of Langerhans; Lymphocyte Count; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred NOD; Spleen; Wharton Jelly | 2015 |
Difference in glucagon-like peptide-1 concentrations between C-peptide negative type 1 diabetes mellitus patients and healthy controls.
The role of glucagon-like peptide-1 (GLP-1) has become a new scientific interest in the field of pathophysiology of type 1 diabetes mellitus (T1DM), but the results of the published studies were contradictory. The aim of our study was therefore to measure fasting and postprandial GLP-1 concentrations in T1DM patients and in healthy controls and to examine the difference in those concentrations between the two groups of subjects.. The cross-sectional study included 30 C-peptide negative T1DM patients, median age 37 years (20-59), with disease duration 22 years (3-45), and 10 healthy controls, median age 30 years (27-47). Fasting and postprandial total and active GLP-1 concentrations were measured by ELISA (ALPCO, USA). The data were statistically analysed by SPSS, and significance level was accepted at P < 0.05.. Both fasting total and active GLP-1 concentrations were significantly lower in T1DM patients (total 0.4 pmol/L, 0-6.4 and active 0.2 pmol/L, 0-1.9) compared with healthy controls (total 3.23 pmol/L, 0.2-5.5 and active 0.8 pmol/L, 0.2-3.6), P = 0.008 for total GLP-1 and P = 0.001 for active GLP-1. After adjustment for age, sex and body mass index, binary logistic regression showed that both fasting total and active GLP-1 remained significantly independently lower in T1DM patients (total GLP-1: OR 2.43, 95% CI 1.203-4.909 and active GLP-1: OR 8.73, 95% CI 1.472-51.787).. T1DM patients had independently lower total and active GLP-1 fasting concentrations in comparison with healthy people, which supports the potential therapeutic role of incretin therapy, along with insulin therapy, in T1DM patients. Topics: Adult; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Down-Regulation; Enzyme-Linked Immunosorbent Assay; Fasting; Female; Glucagon-Like Peptide 1; Hospitals, University; Humans; Hypoglycemic Agents; Insulin; Logistic Models; Male; Middle Aged; Outpatient Clinics, Hospital; Postprandial Period; Sex Characteristics; Young Adult | 2015 |
Proinsulin C-peptide prevents impaired wound healing by activating angiogenesis in diabetes.
Diabetes mellitus disrupts wound repair and leads to the development of chronic wounds, likely due to impaired angiogenesis. We previously demonstrated that human proinsulin C-peptide can protect against vasculopathy in diabetes; however, its role in impaired wound healing in diabetes has not been studied. We investigated the potential roles of C-peptide in protecting against impaired wound healing by inducing angiogenesis using streptozotocin-induced diabetic mice and human umbilical vein endothelial cells. Diabetes delayed wound healing in mouse skin, and C-peptide supplement using osmotic pumps significantly increased the rate of skin wound closure in diabetic mice. Furthermore, C-peptide induced endothelial cell migration and tube formation in dose-dependent manners, with maximal effect at 0.5 nM. These effects were mediated through activation of extracellular signal-regulated kinase 1/2 and Akt, as well as nitric oxide formation. C-peptide-enhanced angiogenesis in vivo was demonstrated by immunohistochemistry and Matrigel plug assays. Our findings highlight an angiogenic role of C-peptide and its ability to protect against impaired wound healing, which may have significant implications in reparative and therapeutic angiogenesis in diabetes. Thus, C-peptide replacement is a promising therapy for impaired angiogenesis and delayed wound healing in diabetes. Topics: Animals; C-Peptide; Cell Movement; Cell Proliferation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Endothelial Cells; Human Umbilical Vein Endothelial Cells; Humans; Male; MAP Kinase Signaling System; Mice, Inbred C57BL; Neovascularization, Physiologic; Skin Ulcer; Wound Healing | 2015 |
C-peptide concentration, mortality and vascular complications in people with Type 2 diabetes. The Skaraborg Diabetes Register.
To study the prognosis of patients with newly diagnosed Type 2 diabetes in primary care in relation to their baseline C-peptide concentration.. C-peptide concentrations were determined in 399 patients aged < 65 years with newly diagnosed Type 2 diabetes using the Skaraborg Diabetes Register, Sweden. Data on cardiovascular complications and death were extracted from national registers and a local study of retinopathy. Statistical analyses were performed using Cox regression.. An analysis of C-peptide concentrations in quartiles, after adjusting for confounders, showed that patients in the highest quartile had a 2.75-fold higher risk of death from all causes compared with those in the lowest quartile (CI 1.17-6.47). By contrast, C-peptide concentration was not associated with the incidence of cardiovascular events or the development of retinopathy.. Measurement of C-peptide concentration at diagnosis could help identify patients who are at high risk and who presumably would benefit from more intensive treatment. Topics: Aging; Biomarkers; Blood Glucose; C-Peptide; Cardiovascular Diseases; Cohort Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Humans; Incidence; Male; Middle Aged; Patient Selection; Prognosis; Proportional Hazards Models; Registries; Risk Factors; Sweden; Time Factors | 2015 |
BMI is an important driver of β-cell loss in type 1 diabetes upon diagnosis in 10 to 18-year-old children.
Body weight-related insulin resistance probably plays a role in progression to type 1 diabetes, but has an uncertain impact following diagnosis. In this study, we investigated whether BMI measured at diagnosis was an independent predictor of C-peptide decline 1-year post-diagnosis.. Multicentre longitudinal study carried out at diagnosis and up to 1-year follow-up.. Data on C-peptide were collected from seven diabetes centres in Europe. Patients were grouped according to age at diagnosis (<5 years, n=126; >5 years <10 years, n=295; >10 years <18 years, n=421; >18 years, n=410). Linear regression was used to investigate whether BMI was an independent predictor of change in fasting C-peptide over 1 year. Models were additionally adjusted for baseline insulin dose and HbA1c.. In individuals diagnosed between 0 and 5 years, 5 and 10 years and those diagnosed >18 years, we found no association between BMI and C-peptide decline. In patients aged 10-18 years, higher BMI at baseline was associated with a greater decline in fasting C-peptide over 1 year with a decrease (β 95% CI; P value) of 0.025 (0.010, 0.041) nM/kg per m(2) higher baseline BMI (P=0.001). This association remained significant after adjusting for gender and differences in HbA1c and insulin dose (β=0.026, 95% CI=0.0097, 0.042; P=0.002).. These observations indicate that increased body weight and increased insulin demand are associated with more rapid disease progression after diagnosis of type 1 diabetes in an age group 10-18 years. This should be considered in studies of β-cell function in type 1 diabetes. Topics: Adolescent; Biomarkers; Body Mass Index; C-Peptide; Cell Count; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin-Secreting Cells; Longitudinal Studies; Male | 2015 |
Changes in circulating adiponectin, leptin, glucose and C-peptide in patients with ketosis-prone diabetes.
To evaluate circulating adipokines in people with ketosis-prone diabetes, a heterogeneous disorder characterized by unprovoked ketoacidosis in people with previously unrecognized diabetes.. Patients presenting with ketoacidosis with no previous diabetes diagnosis were compared with patients with previously established Type 1 diabetes. Baseline assessments of autoimmune status (A+/A-), and β-cell function (B+/B-), as well as leptin and adiponectin levels during a standardized mixed-meal tolerance test of 120 min, were performed. In all, 20 patients with heterogeneous ketosis-prone diabetes and 12 patients with Type 1 diabetes were evaluated at baseline, 12 and 24 months.. At baseline, during a mixed-meal tolerance test, glucose and adiponectin concentrations were lower in patients with ketosis-prone diabetes than in those with Type 1 diabetes (P = 0.0023 and P < 0.0001, respectively), whereas C-peptide concentrations were higher, with no significant difference in leptin concentrations. Within 12 months, 11 patients with ketosis-prone diabetes (all A-/B+) were discontinued from insulin treatment (ketosis-prone diabetes - insulin group), while nine patients (four A-B-, four A+B- and one A-B+) were maintained on insulin (ketosis-prone diabetes + insulin group). Fasting C-peptide levels increased significantly over 24 months in the ketosis-prone diabetes - insulin group (P = 0.01), while HbA1c levels decreased (P < 0.0001). Overall, the ketosis-prone diabetes - insulin group had a higher BMI (P = 0.018), yet a lower fasting glucose concentration (P = 0.003) compared with the ketosis-prone diabetes + insulin group. Over 24 months, the mixed-meal tolerance test area-under-the-curve of C-peptide increased in the ketosis-prone diabetes - insulin group, with no change in ketosis-prone diabetes + insulin (P < 0.0001). At 24 months, in spite of the higher BMI in the ketosis-prone diabetes - insulin group, mixed-meal tolerance test glucose and leptin concentrations were significantly lower (P < 0.0001 and P = 0.017, respectively), while adiponectin levels were higher (P = 0.023) compared with the ketosis-prone diabetes + insulin group.. In spite of the higher BMI in the ketosis-prone diabetes - insulin group, lower leptin and higher adiponectin levels may contribute to improved β-cell function and insulin sensitivity, as evidenced by lower glucose and higher C-peptide levels. This allows insulin therapy to be withdrawn. Topics: Adiponectin; Adolescent; Adult; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin Resistance; Insulin-Secreting Cells; Leptin; Male; Middle Aged; Postprandial Period; Prospective Studies; Time Factors; Young Adult | 2015 |
Neuronal T-cell autoreactivity is amplified in overweight children with new-onset insulin-requiring diabetes.
Disease-associated T-cell autoreactivities are seen in most type 1 diabetic patients and are thought to emerge before islet autoantibodies, but host factors that impact autoimmune elements remain uncertain. We assessed if adiposity and measures of insulin sensitivity impact T- and B-cell autoimmunity in children with insulin-requiring diabetes.. Insulin-requiring children and adolescents diagnosed between January 2004 and June 2008 were studied (n = 261): age 9.7 ± 4 years, 92% white, and 60% male. T-cell responses to 10 diabetes-associated antigens, β-cell autoantibodies (GADA, IA-2A, IAA, and ICA), BMI z score (BMIz), and waist percentile were measured at onset and 3 months later.. All but one subject had either T- or B-cell autoimmunity. Diabetes-associated T-cell autoreactivities were found in 92% of subjects. Higher amplitude T-cell autoreactivities to neuronal diabetes-associated autoantigens were seen in those with the highest BMIz quintile, BMI ≥85th percentile (P < 0.05), and waist circumference ≥85th percentile (P < 0.05). There were no relationships between the number of T-cell reactivities or T-cell diversity with adiposity measures or autoantibody number or type. Patients with positive T-cell reactivities but without autoantibodies had the highest BMIz (P = 0.006).. Our observations link obesity and diabetes-related autoimmunity, suggesting an amplification of neuronal T-cell autoimmunity associated with adiposity and/or insulin resistance, with obesity-related inflammation possibly enhancing islet autoimmunity. Topics: Adolescent; Alleles; Autoantibodies; Autoantigens; Autoimmunity; B-Lymphocytes; Body Mass Index; C-Peptide; Cell Proliferation; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Male; Pediatric Obesity; T-Lymphocytes; Waist Circumference | 2015 |
Demonstration of an intrinsic relationship between endogenous C-peptide concentration and determinants of glycemic control in type 1 diabetes following islet transplantation.
Maintenance of endogenous pancreatic β-cell function could be an important goal in the management of type 1 diabetes. However, the impact of stimulated C-peptide level on overall glycemic control is unknown. The relationship between C-peptide and parameters of glucose control was therefore characterized in a cohort with rapidly changing β-cell function following islet transplantation.. Standardized mixed-meal tolerance test was undertaken in 12 consecutive islet recipients at 1-6-month intervals, with graft function determined by 90-min stimulated C-peptide. Continuous glucose monitoring was undertaken in the week preceding each assessment and the relationship between C-peptide and glucose control evaluated by mixed Poisson regression.. Recipients completed 5 (1-14) [median (range)] clinical assessments over 18 (1-51) months posttransplant encompassing a wide range of stimulated C-peptide levels (7-2,622 pmol/L). Increasing β-cell function across predefined C-peptide groups was associated with reduced insulin dose, HbA1c, mean glucose (low [<200 pmol/L] 10.7 vs. excellent [>1,000 pmol/L] 7.5 mmol/L), and glucose SD (low, 4.4 vs. excellent, 1.4 mmol/L). Highly statistically significant continuous associations between stimulated C-peptide and mean interstitial glucose (lower by 2.5% [95% CI 1.5-3.5%] per 100 pmol/L higher C-peptide), glucose SD, time outside glucose target range, and measures of hyper-/hypoglycemia risk were confirmed.. Repeated assessment of islet transplant recipients has enabled modeling of the relationship between endogenous β-cell function and measures of glycemic control providing quantitative estimates of likely impact of an acute change in β-cell function in individuals with type 1 diabetes. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Prospective Studies | 2015 |
High frequency of activated NKp46(+) natural killer cells in patients with new diagnosed of latent autoimmune diabetes in adults.
To determine the potential association of different subsets of NK cells with the development of latent autoimmune diabetes of adults (LADA) in patients. The frequency of different subsets of NK and NKT cells, including IFN-γ(+) and CD107a(+) NK and NKT cells, in 27 patients with newly diagnosed LADA and 20 healthy controls (HC) were determined by flow cytometry. The concentrations of serum autoantibodies against GAD65 were measured by direct radioligand assay. The potential association of the frequency of NK cells with clinical measures was analyzed. In comparison with that in the HC, significantly higher frequency of peripheral blood NK and NKp46(+) NK cells, but lower frequency of KIR3DL1(+) NK cells were detected in patients with newly diagnosed LADA (p < 0.0001, p < 0.0001, p = 0.0039, respectively). The percentages of inducible IFN-γ(+) NK cells were significantly higher in the LADA patients than that in the HC (p < 0.0001). Moreover, the percentages of NKp46(+) NK cells were negatively correlated with the levels of fasting plasma C-peptide in patients (R = -0.4877, p = 0.0099). There was no significant difference in the frequency of spontaneous and inducible CD107a(+) between patients and controls. Our data indicate a higher frequency of activated NKp46(+) NK cells may be associated with the development of LADA in humans. Topics: Adult; Antigens, Surface; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Flow Cytometry; Humans; Immunophenotyping; Interferon-gamma; Killer Cells, Natural; Lymphocyte Activation; Lymphocyte Count; Male; Middle Aged; Natural Cytotoxicity Triggering Receptor 1 | 2015 |
Prevalence of detectable C-Peptide according to age at diagnosis and duration of type 1 diabetes.
It is generally accepted that complete β-cell destruction eventually occurs in individuals with type 1 diabetes, which has implications for treatment approaches and insurance coverage. The frequency of residual insulin secretion in a large cohort of individuals at varying ages of diagnosis and type 1 diabetes duration is unknown.. The frequency of residual insulin secretion was determined by measurement of nonfasting serum C-peptide concentration in 919 individuals with type 1 diabetes according to prespecified groups based on age at diagnosis and duration of disease (from 3 to 81 years' duration). Stimulated C-peptide was measured in those with detectable nonfasting values and a group of those with undetectable values as control.. The overall frequency of detectable nonfasting C-peptide was 29%, decreasing with time from diagnosis regardless of age at diagnosis. In all duration groups, the frequency of C-peptide was higher with diagnosis age >18 years compared with ≤18 years. Nineteen percent of those with undetectable nonfasting C-peptide were C-peptide positive upon stimulation testing.. The American Diabetes Association's definition of type 1 diabetes as "usually leading to absolute insulin deficiency" results in clinicians often considering the presence of residual insulin secretion as unexpected in this population. However, our data suggest that residual secretion is present in almost one out of three individuals 3 or more years from type 1 diabetes diagnosis. The frequency of residual C-peptide decreases with time from diagnosis regardless of age at diagnosis, yet at all durations of disease, diagnosis during adulthood is associated with greater frequency and higher values of C-peptide. Topics: Adolescent; Adult; Aged; Aged, 80 and over; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Prevalence; Young Adult | 2015 |
Most people with long-duration type 1 diabetes in a large population-based study are insulin microsecretors.
Small studies using ultrasensitive C-peptide assays suggest endogenous insulin secretion is frequently detectable in patients with long-standing type 1 diabetes (T1D), but these studies do not use representative samples. We aimed to use the stimulated urine C-peptide-to-creatinine ratio (UCPCR) to assess C-peptide levels in a large cross-sectional, population-based study of patients with T1D.. We recruited 924 patients from primary and secondary care in two U.K. centers who had a clinical diagnosis of T1D, were under 30 years of age when they received a diagnosis, and had a diabetes duration of >5 years. The median age at diagnosis was 11 years (interquartile range 6-17 years), and the duration of diabetes was 19 years (11-27 years). All provided a home postmeal UCPCR, which was measured using a Roche electrochemiluminescence assay.. Eighty percent of patients (740 of 924 patients) had detectable endogenous C-peptide levels (UCPCR >0.001 nmol/mmol). Most patients (52%, 483 of 924 patients) had historically very low undetectable levels (UCPCR 0.0013-0.03 nmol/mmol); 8% of patients (70 of 924 patients) had a UCPCR ≥0.2 nmol/mmol, equivalent to serum levels associated with reduced complications and hypoglycemia. Absolute UCPCR levels fell with duration of disease. Age at diagnosis and duration of disease were independent predictors of C-peptide level in multivariate modeling.. This population-based study shows that the majority of long-duration T1D patients have detectable urine C-peptide levels. While the majority of patients are insulin microsecretors, some maintain clinically relevant endogenous insulin secretion for many years after the diagnosis of diabetes. Understanding this may lead to a better understanding of pathogenesis in T1D and open new possibilities for treatment. Topics: Adult; C-Peptide; Child; Creatinine; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Insulin; Insulin Secretion; Male; Postprandial Period; Time Factors; Young Adult | 2015 |
A new approach for diagnosing type 1 diabetes in autoantibody-positive individuals based on prediction and natural history.
We assessed whether type 1 diabetes (T1D) can be diagnosed earlier using a new approach based on prediction and natural history in autoantibody-positive individuals.. Diabetes Prevention Trial-Type 1 (DPT-1) and TrialNet Natural History Study (TNNHS) participants were studied. A metabolic index, the T1D Diagnostic Index60 (Index60), was developed from 2-h oral glucose tolerance tests (OGTTs) using the log fasting C-peptide, 60-min C-peptide, and 60-min glucose. OGTTs with Index60 ≥2.00 and 2-h glucose <200 mg/dL (Ind60+Only) were compared with Index60 <2.00 and 2-h glucose ≥200 mg/dL (2hglu+Only) OGTTs as criteria for T1D. Individuals were assessed for C-peptide loss from the first Ind60+Only OGTT to diagnosis.. Areas under receiver operating characteristic curves were significantly higher for Index60 than for the 2-h glucose (P < 0.001 for both DPT-1 and the TNNHS). As a diagnostic criterion, sensitivity was higher for Ind60+Only than for 2hglu+Only (0.44 vs. 0.15 in DPT-1; 0.26 vs. 0.17 in the TNNHS) OGTTs. Specificity was somewhat higher for 2hglu+Only OGTTs in DPT-1 (0.97 vs. 0.91) but equivalent in the TNNHS (0.98 for both). Positive and negative predictive values were higher for Ind60+Only OGTTs in both studies. Postchallenge C-peptide levels declined significantly at each OGTT time point from the first Ind60+Only OGTT to the time of standard diagnosis (range -22 to -34% in DPT-1 and -14 to -27% in the TNNHS). C-peptide and glucose patterns differed markedly between Ind60+Only and 2hglu+Only OGTTs.. An approach based on prediction and natural history appears to have utility for diagnosing T1D. Topics: Adult; Autoantibodies; Biological Assay; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Early Diagnosis; Epidemiologic Methods; Fasting; Female; Glucose Tolerance Test; Humans; Male; Middle Aged; ROC Curve | 2015 |
Heterogeneity in recent-onset type 1 diabetes - a clinical trial perspective.
Type 1 diabetes (T1D) TrialNet is a National Institutes of Health-sponsored clinical trial network aimed at altering the disease course of T1D. The purpose of this study is to evaluate age-dependent heterogeneity in clinical, metabolic and immunologic characteristics of individuals with recent-onset T1D, to identify cohorts of interest and to aid in planning of future studies.. Eight hundred eighty-three individuals with recent-onset T1D involved in five TrialNet studies were categorized by age as follows: ≥18 years, 12-17 years, 8-12 years and <8 years. Data were compared with healthy age-matched subjects in the National Health and Nutrition Examination Survey.. Only 2.0% of the individuals overall were excluded from trial participation because of insufficient C-peptide values (<0.2 pmol/mL). A disproportionate number of these subjects were <8 years old. Leukopenia was present in 21.2% of individuals and lymphopenia in 11.6%; these frequencies were markedly higher than age-matched healthy National Health and Nutrition Examination Survey population. Of the cohort, 24.5% were overweight or obese. Neither high-risk human leukocyte antigen type DR3 nor DR4 was present in 31% of adults and 21% of children.. The ability of recent-onset T1D patients to meet key entry criteria for TrialNet studies, including C-peptide >0.2 pmol/mL, varies by age. Lower C-peptide level requirements for younger participants and other aspects of heterogeneity of recent-onset T1D patients, such as white blood cell count abnormalities and body mass index should be considered in the design of future clinical studies. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Biomarkers; Body Mass Index; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Humans; Italy; Leukopenia; Lymphopenia; Middle Aged; North America; Obesity; Overweight; Pediatric Obesity; Young Adult | 2015 |
Circulating betatrophin is elevated in patients with type 1 and type 2 diabetes.
There is evidence that betatrophin, a hormone derived from adipose tissue and liver, affects the proliferation of pancreatic beta cells in mice. The aim of this study was to examine circulating betatrophin concentrations in Japanese healthy controls and patients with type 1 and type 2 diabetes. A total of 76 subjects (12 healthy controls, 34 type 1 diabetes, 30 type 2 diabetes) were enrolled in the study. Circulating betatrophin was measured with an ELISA kit and clinical parameters related to betatrophin were analyzed statistically. Circulating betatrophin (Log transformed) was significantly increased in patients with diabetes compared with healthy subjects (healthy controls, 2.29 ± 0.51; type 1 diabetes, 2.94 ± 0.44; type 2 diabetes, 3.17 ± 0.18; p<0.001, 4.1 to 5.4 times in pg/mL order). Age, HbA1c, fasting plasma glucose and Log triglyceride were strongly associated with Log betatrophin in all subjects (n=76) in correlation analysis. In type 1 diabetes, there was a correlation between Log betatrophin and Log CPR. These results provide the first evidence that circulating betatrophin is significantly elevated in Japanese patients with diabetes. The findings of this pilot study also suggest a possibility of association between the level of betatrophin and the levels of glucose and triglycerides. Topics: Adult; Aged; Angiopoietin-Like Protein 8; Angiopoietin-like Proteins; Blood Glucose; C-Peptide; Cholesterol, HDL; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glycated Hemoglobin; Humans; Japan; Male; Middle Aged; Peptide Hormones; Triglycerides | 2015 |
The development and utility of a novel scale that quantifies the glycemic progression toward type 1 diabetes over 6 months.
We developed a scale to serve as a potential end point for 6-month glycemic progression (PS6M) toward type 1 diabetes (T1D) in autoantibody-positive relatives of individuals with T1D.. The PS6M was developed from Diabetes Prevention Trial-Type 1 (DPT-1) data and tested in the TrialNet Pathway to Prevention Study (PTP). It is the difference between 6-month glucose sum values (30-120 min oral glucose tolerance test values) and values predicted for nonprogressors.. The PS6M predicted T1D in the PTP (P < 0.001). The area under the receiver operating chacteristic curve was greater (P < 0.001) for the PS6M than for the baseline-to-6-month difference. PS6M values were higher in those with two or more autoantibodies, 30-0 min C-peptide values <2.00 ng/mL, or DPT-1 Risk Scores >7.00 (P < 0.001 for all).. The PS6M is an indicator of short-term glycemic progression to T1D that could be a useful tool for assessing preventive treatments and biomarkers. Topics: Adolescent; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Female; Glucose Tolerance Test; Humans; Hyperglycemia; Male; Patient Acuity; Risk Factors; Severity of Illness Index | 2015 |
TNF-α Antibody Therapy in Combination With the T-Cell-Specific Antibody Anti-TCR Reverses the Diabetic Metabolic State in the LEW.1AR1-iddm Rat.
Anti-tumor necrosis factor-α (TNF-α) therapy (5 mg/kg body weight), alone or combined with the T-cell-specific antibody anti-T-cell receptor (TCR) (0.5 mg/kg body weight), was performed over 5 days immediately after disease manifestation to reverse the diabetic metabolic state in the LEW.1AR1-iddm rat, an animal model of human type 1 diabetes. Only combination therapy starting at blood glucose concentrations below 15 mmol/L restored normoglycemia and normalized C-peptide. Increased β-cell proliferation and reduced apoptosis led to a restoration of β-cell mass along with an immune cell infiltration-free pancreas 60 days after the end of therapy. This combination of two antibodies, anti-TCR/CD3, as a cornerstone compound in anti-T-cell therapy, and anti-TNF-α, as the most prominent and effective therapeutic antibody in suppressing TNF-α action in many autoimmune diseases, was able to reverse the diabetic metabolic state. With increasing blood glucose concentrations during the disease progression, however, the proapoptotic pressure on the residual β-cell mass increased, ultimately reaching a point where the reservoir of the surviving β-cells was insufficient to allow a restoration of normal β-cell mass through regeneration. The present results may open a therapeutic window for reversal of diabetic hyperglycemia in patients, worthwhile of being tested in clinical trials. Topics: Animals; Antibodies, Monoclonal; Blood Glucose; C-Peptide; Cell Proliferation; Diabetes Mellitus, Type 1; Disease Models, Animal; Insulin; Male; Rats; Rats, Inbred Lew; T-Lymphocytes; Tumor Necrosis Factor-alpha | 2015 |
Urinary C-Peptide/Creatinine Ratio Can Distinguish Maturity-Onset Diabetes of the Young from Type 1 Diabetes in Children and Adolescents: A Single-Center Experience.
The urinary C-peptide/creatinine ratio (UCPCR) and fasting C-peptide level can assess beta-cell function in clinical practice. In the present study, the use of the UCPCR and fasting C-peptide levels was investigated in the differential diagnosis between maturity-onset diabetes of the young (MODY) and type 1 diabetes mellitus (T1DM).. Twenty-seven patients with genetically confirmed MODY by next-generation sequence analysis and 42 children with T1DM were included. C-peptide levels were measured after an overnight fast before breakfast, and urine samples were collected 2 h after a standard lunch in the hospital.. The UCPCR in the T1DM group was 0.17 ± 0.5 nmol/mmol, and in the MODY group it was 1.27 ± 1.03 nmol/mmol (p = 0.001). The receiver operating characteristic (ROC) curves showed excellent discrimination (area under the curve 0.93). A UCPCR ≥0.22 nmol/mmol yielded a 96.3% sensitivity and an 85.7% specificity. The fasting C-peptide level in the T1DM group was lower than that in the MODY group (p = 0.001). The fasting C-peptide cutoff determined by ROC curve analysis was 0.62 ng/ml, with a sensitivity of 93% and a specificity of 90% for discriminating between MODY and T1DM.. We showed that the UCPCR and fasting C-peptide levels in children and adolescents can distinguish patients with MODY from patients with T1DM with high specificity and sensitivity. A value of UCPCR ≥0.22 nmol/mmol may indicate further genetic testing for MODY. Topics: Adolescent; C-Peptide; Child; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Male | 2015 |
C-peptide and zinc delivery to erythrocytes requires the presence of albumin: implications in diabetes explored with a 3D-printed fluidic device.
People with type 1 diabetes (T1D) must administer insulin exogenously due to the destruction of their pancreatic β-cells. Endogenous insulin is stored in β-cell granules along with C-peptide, a 31 amino acid peptide that is secreted from these granules in amounts equal to insulin. Exogenous co-administration of C-peptide with insulin has proven to reduce diabetes-associated complications in animals and humans. The exact mechanism of C-peptide's beneficial effects after secretion from the β-cell granules is not completely understood, thus hindering its development as an exogenously administered hormone. Monitoring tissue-to-tissue communication using a 3D-printed microfluidic device revealed that zinc and C-peptide are being delivered to erythrocytes by albumin. Upon delivery, erythrocyte-derived ATP increased by >50%, as did endothelium-derived NO, which was measured downstream in the 3D-printed device. Our results suggest that hormone replacement therapy in diabetes may be improved by exogenous administration of a C-peptide ensemble that includes zinc and albumin. Topics: Adenosine Triphosphate; Albumins; Animals; C-Peptide; Calorimetry; Cell Communication; Cell Line; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Erythrocytes; Humans; Insulin-Secreting Cells; Lab-On-A-Chip Devices; Microfluidics; Peptides; Printing, Three-Dimensional; Rats; Zinc | 2015 |
Graft function 1 year after pregnancy in an islet-transplanted patient.
Pancreatic islet transplantation is a treatment option for patients with type 1 diabetes (T1D), but pregnancy has generally not been advised for women after receiving an islet allograft. We hereby describe what is to our knowledge the first successful pregnancy and persistent graft function in a woman 4 years after her initial islet transplantation. A 37-year-old woman with brittle type 1 diabetes was transplanted with two separate islet graft infusions, eventually becoming insulin independent. Ten months after her second transplantation, her immunosuppression was switched from tacrolimus and sirolimus to tacrolimus, azathioprine, and prednisolone, due to her wish to become pregnant. She became pregnant one year later, and after 38 weeks of uncomplicated pregnancy, she gave birth to a healthy child by C-section. The current report suggests that pregnancy and childbirth can be accomplished after islet transplantation without loss of islet graft function. Topics: Adult; C-Peptide; Cesarean Section; Diabetes Mellitus, Type 1; Drug Substitution; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Infant, Newborn; Islets of Langerhans; Islets of Langerhans Transplantation; Pregnancy; Pregnancy Complications; Reoperation; Transplants | 2015 |
Efficacy of a long-acting C-peptide analogue against peripheral neuropathy in streptozotocin-diabetic mice.
To investigate the efficacy of a pegylated C-peptide (Peg-C-peptide) against indices of peripheral neuropathy in a mouse model of type 1 diabetes and to compare efficacy of this C-peptide analogue against that of the native molecule.. C57Bl/6 mice were injected with two consecutive doses of streptozotocin (STZ) to induce type 1 diabetes. Mice were treated twice daily with native C-peptide [0.4-1.3 mg/kg subcutaneously (s.c.)] or twice weekly with Peg-C-peptide (0.1-1.3 mg/kg s.c.) for 20 weeks. Motor and sensory nerve conduction velocities, thermal and tactile responses and rate dependent H-wave depression were assessed after 20 weeks of diabetes. Foot skin intraepidermal fibres and corneal nerves were counted, and sciatic nerve substance P and plasma C-peptide levels were also determined.. After 5 months of STZ-induced diabetes, mice exhibited significant motor and sensory nerve conduction slowing, thermal hypoalgesia, tactile allodynia and attenuation of rate-dependent depression of the H reflex. These functional disorders were accompanied by nerve substance P depletion but not loss of small sensory fibres in the hind paw epidermis or the cornea. The efficacy of twice-daily treatment with native C-peptide in preventing these disorders was matched or exceeded by twice-weekly treatment with Peg-C-peptide. Both native and Peg-C-peptide also increased corneal nerve occupancy in the sub-basal nerve plexus of control rats.. These data identify actions of C-peptide against novel and clinically pertinent aspects of diabetic neuropathy in mice and also establish Peg-C-peptide as a long-acting therapeutic method of potential clinical value. Topics: Animals; C-Peptide; Cornea; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drug Administration Schedule; Epidermis; Hindlimb; Mice; Mice, Inbred C57BL; Models, Animal; Neural Conduction; Rats; Sciatic Nerve | 2015 |
Islet Amyloid in Whole Pancreas Transplants for Type 1 Diabetes Mellitus (DM): Possible Role of Type 2 DM for Graft Failure.
Long-term results with whole pancreas (WPTx) and islet transplantation (IT) continue to be suboptimal. Graft failure with undetectable C-peptide level is attributed to graft sclerosis (chronic rejection), recurrence of Type 1 diabetes mellitus (DM), or insufficient islet mass. In contrast, graft failure with measurable C-peptide has overlapping clinical features with Type 2 DM (suggesting persistent but insufficient β cell function), but is poorly understood. In general, the morphological substrate for islet failure is unclear because grafted islets are not routinely evaluated. We present two patients with graft failure at 5 and 8 years after successful WPTx for Type 1 DM, presenting with preserved C-peptide levels. On histopathology, the islets had preserved both α and β cell populations but also prominent accumulation of islet amyloid (IA), the morphological hallmark of Type 2 DM. IA previously reported in IT, represents fibrillary aggregates of islet amyloid polypeptide, a hormone normally cosecreted with insulin. Accumulation of IA correlates quantitatively with the development of hyperglycemia and is known to cause β cell dysfunction and loss. Accumulation of IA and development of Type 2 DM should be considered and studied as a potential cause of long-term islet failure in IT and WPTx. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Graft Rejection; Humans; Islet Amyloid Polypeptide; Islets of Langerhans; Male; Middle Aged; Pancreas Transplantation; Prognosis; Risk Factors | 2015 |
Transplantation of insulin-producing cells to treat diabetic rats after 90% pancreatectomy.
To investigate the effects of transplantation of insulin-producing cells (IPCs) in the treatment of diabetic rats after 90% pancreatectomy.. Human umbilical cord mesenchymal stem cells (UCMSCs) were isolated and induced into IPCs using differentiation medium. Differentiated cells were examined by dithizone (DTZ) staining, reverse transcription-polymerase chain reaction (RT-PCR), and real-time RT-PCR. C-peptide release, both spontaneously and after glucose challenge, was measured by ELISA. IPCs were then transplanted into Sprague-Dawley rats after 90% pancreatectomy and blood glucose levels and body weight were measured.. The differentiated cells were positive for DTZ staining and expressed pancreatic β-cell related genes. C-peptide release by the differentiated cells increased after glucose challenge (380.6 ± 15.32 pmol/L vs 272.4 ± 15.32 pmol/L, P < 0.05). Further, in the cell transplantation group, blood sugar levels were significantly lower than in the sham group 2 wk after transplantation (18.7 ± 2.5 mmol/L vs 25.8 ± 1.25 mmol/L, P < 0.05). Glucose tolerance tests showed that 45 min after intraperitoneal glucose injection, blood glucose levels were significantly lower on day 56 after transplantation of IPCs (12.5 ± 4.7 mmol/L vs 42.2 ± 9.3 mmol/L, P < 0.05).. Our results show that UCMSCs can differentiate into islet-like cells in vitro under certain conditions, which can function as IPCs both in vivo and in vitro. Topics: Animals; Blood Glucose; Body Weight; C-Peptide; Cell Differentiation; Cell Proliferation; Cell Shape; Cells, Cultured; Cord Blood Stem Cell Transplantation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Gene Expression Regulation; Glucose Tolerance Test; Humans; Insulin-Secreting Cells; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Pancreatectomy; Rats, Sprague-Dawley; Time Factors; Umbilical Cord; Wharton Jelly | 2015 |
Vitamin D intake associates with insulin resistance in type 2 diabetes, but not in latent autoimmune diabetes in adults.
This study aimed to evaluate the relationship between vitamin D (vitD) intake and serum concentrations and insulin secretion (assessed by C-peptide serum concentration)/insulin resistance (determined by estimated glucose disposal rate [eGDR]) in patients with latent autoimmune diabetes in adults (LADA) and type 2 diabetes (T2DM). C-peptide, serum vitD, lipid profile, insulin, glucose, and glycosylated hemoglobin (HbA1c) were assessed; vitD intake was determined; and eGDR was calculated. Groups were compared using the Student t or Mann-Whitney U test. Correlations were performed between insulin secretion, insulin resistance, and vitD, and linear regression models were adjusted for confounding variables. Of 107 patients included, age was 55.3 ± 11.84 years old, and time since diabetes diagnosis was 13.23 ± 5.96 years. There were significant intergroup differences in age, body mass index (BMI), hip measurements, glucose, and HbA1c. The correlation between vitD intake and C-peptide for the whole group was significant (r = 0.213; P = .032) as well as for vitD deficiency/sufficiency in T2DM (P = .042), whereas neither was significant in eGDR. After adjustment for age, HbA1c, disease progression, physical activity, solar exposure, sex, and BMI, vitD intake was only significant in T2DM (P = .028). In serum vitD, only the correlation between eGDR and vitD in T2DM was significant and intragroup when comparing vitD sufficiency. After adjustments, significance was lost. Patients with LADA had lower intake of vitD, poorer metabolic control, lower BMI, and younger age compared to T2DM patients. There was no association between serum vitD or vitD intake and insulin secretion when analyzed by group, although vitD intake was associated with insulin resistance in T2DM, but not LADA. Topics: Adult; Aged; Blood Glucose; Body Mass Index; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Energy Intake; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Insulin Secretion; Linear Models; Male; Middle Aged; Motor Activity; Surveys and Questionnaires; Vitamin D | 2015 |
Statistical considerations when analyzing biomarker data.
Biomarkers have become, and will continue to become, increasingly important to clinical immunology research. Yet, biomarkers often present new problems and raise new statistical and study design issues to scientists working in clinical immunology. In this paper I discuss statistical considerations related to the important biomarker problems of: 1) The design and analysis of clinical studies which seek to determine whether changes from baseline in a biomarker are associated with changes in a metabolic outcome; 2) The conditions that are required for a biomarker to be considered a "surrogate"; 3) Considerations that arise when analyzing whether or not a predictive biomarker could act as a surrogate endpoint; 4) Biomarker timing relative to the clinical endpoint; 5) The problem of analyzing studies that measure many biomarkers from few subjects; and, 6) The use of statistical models when analyzing biomarker data arising from count data. Topics: Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Humans; Immunologic Factors; Models, Statistical; Outcome Assessment, Health Care; Research Design; Rituximab; Time Factors | 2015 |
Low levels of C-peptide have clinical significance for established Type 1 diabetes.
To determine whether the low C-peptide levels (< 50 pmol/l) produced by the pancreas for decades after onset of Type 1 diabetes have clinical significance.. We evaluated fasting C-peptide levels, duration of disease and age of onset in a large cross-sectional series (n = 1272) of people with Type 1 diabetes. We then expanded the scope of the study to include the relationship between C-peptide and HbA1c control (n = 1273), as well as diabetic complications (n = 324) and presence of hypoglycaemia (n = 323). The full range of C-peptide levels was also compared with 1,5-Anhydroglucitol, a glucose responsive marker.. C-peptide levels declined for decades after diagnosis, and the rate of decline was significantly related to age of onset (P < 0.0001), after adjusting for disease duration. C-peptide levels > 10 pmol/l were associated with protection from complications (e.g. nephropathy, neuropathy, foot ulcers and retinopathy; P = 0.03). Low C-peptide levels were associated with poor metabolic control measured by HbA1c (P < 0.0001). Severe hypoglycaemia was associated with the lowest C-peptide levels compared with mild (P = 0.049) or moderate (P = 0.04) hypoglycaemia. All levels of measurable C-peptide were responsive to acute fluctuations in blood glucose levels as assessed by 1,5-Anhydroglucitol (P < 0.0001).. Low C-peptide levels have clinical significance and appear helpful in characterizing groups at-risk for faster C-peptide decline, complications, poorer metabolic control and severe hypoglycaemia. Low C-peptide levels may be a biomarker for characterizing at-risk patients with Type 1 diabetes. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blood Glucose; C-Peptide; Child; Cross-Sectional Studies; Deoxyglucose; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Middle Aged; Prognosis; Young Adult | 2015 |
Long-term immunosuppression after solitary islet transplantation is associated with preserved C-peptide secretion for more than a decade.
We report on two patients with type 1 diabetes (T1D) after solitary islet transplantation in 2001. They received steroid-sparing immunosuppression (daclizumab, sirolimus, and tacrolimus according to the Edmonton protocol). Both patients became insulin independent for 2 years: Patient A, a 42-year-old female with a 12-year history of T1D, received two islet infusions; patient B, a 53-year-old female with a 40-year T1D history, received one islet infusion. Pretransplant, both had undetectable C-peptide concentrations and frequent and severe hypoglycemia. Pretransplant, hemoglobin A1c (HbA1c) was 7.8% and 8.8% and insulin requirements were 0.47 and 0.33 units/kg/day, respectively. Posttransplant, C-peptide levels remained detectable while immunosuppression was continued, but decreased over time. Insulin was re-started 2 years posttransplant in both patients. Since patient A's glycemia and insulin requirements trended toward pretransplant levels, immunosuppression was discontinued after 13 years. This resulted in a sudden cessation of C-peptide secretion. Patient B continues on immunosuppression, has better HbA1c, and half the insulin requirement compared to pretransplant. Both patients no longer experience severe hypoglycemia. Herein, we document blood glucose concentrations over time (>30 000 measurements per patient) and β cell function based on C-peptide secretion. Despite renewed insulin dependence, both patients express satisfaction with having undergone the procedure. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Middle Aged; Monitoring, Physiologic; Patient Satisfaction; Postoperative Care; Quality of Life; Risk Assessment; Sampling Studies; Severity of Illness Index; Time Factors; Treatment Outcome | 2015 |
Combination Therapy Reverses Hyperglycemia in NOD Mice With Established Type 1 Diabetes.
An increasing number of therapies have proven effective at reversing hyperglycemia in the nonobese diabetic (NOD) mouse model of type 1 diabetes (T1D), yet situations of successful translation to human T1D are limited. This may be partly due to evaluating the effect of treating immediately at diagnosis in mice, which may not be reflective of the advanced disease state in humans at disease onset. In this study, we treated NOD mice with new-onset as well as established disease using various combinations of four drugs: antithymocyte globulin (ATG), granulocyte-colony stimulating factor (G-CSF), a dipeptidyl peptidase IV inhibitor (DPP-4i), and a proton pump inhibitor (PPI). Therapy with all four drugs induced remission in 83% of new-onset mice and, remarkably, in 50% of NOD mice with established disease. Also noteworthy, disease remission occurred irrespective of initial blood glucose values and mechanistically was characterized by enhanced immunoregulation involving alterations in CD4+ T cells, CD8+ T cells, and natural killer cells. This combination therapy also allowed for effective treatment at reduced drug doses (compared with effective monotherapy), thereby minimizing potential adverse effects while retaining efficacy. This combination of approved drugs demonstrates a novel ability to reverse T1D, thereby warranting translational consideration. Topics: Animals; Antilymphocyte Serum; C-Peptide; Diabetes Mellitus, Type 1; Dipeptidyl-Peptidase IV Inhibitors; Drug Therapy, Combination; Female; Granulocyte Colony-Stimulating Factor; Hyperglycemia; Insulin; Mice; Mice, Inbred NOD; Pancreas; Proton Pump Inhibitors; Treatment Outcome | 2015 |
First identification of Flatbush diabetes in patients of Indian origin.
Topics: Adult; Bicarbonates; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glycated Hemoglobin; Humans; Hydrogen-Ion Concentration; India; Insulin; Ketones; Male | 2015 |
GLP-1 receptor agonists in type 1 diabetes: a proof-of-concept approach.
To test potential efficacy of liraglutide, a GLP-1 receptor agonist, in subjects with type 1 diabetes (T1DM).. We have recruited nine T1DM patients (age 40.1 ± 6.4 years, duration of diabetes 19.2 ± 8.8 years, BMI 24.3 ± 3.5 kg/m(2), HbA1c 8.2 ± 1.0 %-66 ± 11 mmol/mol, daily insulin dose: 0.6 ± 0.1 IU/kg) on continuous subcutaneous insulin therapy with undetectable C-peptide. In addition to existing treatment was administered in single-blind (a) therapy subcutaneously with 0.1 ml of saline solution for 3 days and (b) 0.1 ml of liraglutide (0.6 mg/day) for a further 3 days with daily glucose excursions recorded by continuous glucose monitoring.. Adding liraglutide resulted in a significant reduction in mean blood glucose (138 ± 29 vs. 163 ± 29 mg/dl, p < 0.0001) and standard deviation (42 ± 9 vs. 60 ± 15 mg/dl, p < 0.0001). The area under the curve (AUC) for blood glucose >140 mg/dl was also significantly reduced (22.2 ± 16.4 vs. 41.1 ± 19.7 mg/dl h, p < 0.05) with no difference in AUC for blood glucose <70 mg/dl (liraglutide 0.7 ± 0.9 mg/dl h; placebo: 0.8 ± 1.4 mg/dl h, p = NS). Finally, adding liraglutide reduced daily insulin requirement (37.5 ± 17.2 vs. 42.9 ± 22.4 UI/day, p < 0.01).. Short-term treatment with liraglutide, in T1DM, reduces average blood glucose, blood glucose variability and daily insulin requirement without increasing risk of hypoglycemia. Topics: Adult; Aged; Area Under Curve; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon-Like Peptide-1 Receptor; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Liraglutide; Male; Middle Aged | 2015 |
Comparison of Metabolic Outcomes in Children Diagnosed with Type 1 Diabetes Through Research Screening (Diabetes Autoimmunity Study in the Young [DAISY]) Versus in the Community.
Children with positive islet autoantibodies monitored prospectively avoid metabolic decompensation at type 1 diabetes (T1D) diagnosis. However, the effects of early diagnosis and treatment on preservation of insulin secretion and long-term metabolic control are unknown. We compared characteristics of children detected through research screening (Diabetes Autoimmunity Study in the Young [DAISY]) versus community controls at baseline and, in a subset, 6- and 12-month metabolic outcomes.. This was a case-control study comparing DAISY children with T1D to children diagnosed in the general community. All participants underwent mixed-meal tolerance testing; a subset wore a continuous glucose monitoring (CGM) device. Fasting and stimulated C-peptide levels, insulin dose-adjusted hemoglobin A1c (IDAA1c), and CGM variables were compared.. Children (21 DAISY, 21 community) were enrolled and matched by age, time of diagnosis, and diabetes duration; 18 were enrolled within 2 months and 24 within 2.5 years on average from diagnosis. In the overall group and the subgroup of participants enrolled 2.5 years from diagnosis, there were no IDAA1c or C-peptide differences between DAISY versus community children. The subgroup of DAISY versus community children enrolled near diagnosis, however, had lower baseline hemoglobin A1c (6.5±1.4% vs. 9.2±2.9%; P=0.0007) and IDAA1c (7.4±2.1% vs. 11.2±3.5%; P=0.04) and higher stimulated C-peptide (2.5±0.5 vs. 1.6±0.2 ng/mL; P=0.02). In this subgroup, IDAA1c differences persisted at 6 months but not at 1 year. CGM analyses revealed lower minimum overnight glycemia in community children (72 vs. 119 mg/dL; P=0.01).. Favorable patterns of IDAA1c and C-peptide seen in research-screened versus community-diagnosed children with T1D within 2 months of diagnosis are no longer apparent 1 year from diagnosis. Topics: Adolescent; Age of Onset; Autoimmunity; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Case-Control Studies; Child; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Early Diagnosis; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Mass Screening; Prospective Studies | 2015 |
Predictive factors for prolonged remission after autologous hematopoietic stem cell transplantation in young patients with type 1 diabetes mellitus.
Autologous hematopoietic stem cell transplantation (auto-HSCT) followed by immunoablation is a promising therapy for type 1 diabetes mellitus (T1DM) treatment due to the immunosuppression and immunomodulation mechanisms. Indeed, a considerable number of patients have been able to discontinue insulin use with this treatment. However, nonresponse and relapse occur after auto-HSCT. It is important to select the patients who can potentially benefit from this treatment, but the factors that might influence the therapeutic outcome are unclear. The objective of this study was to explore the predictors for prolonged remission after auto-HSCT therapy.. The data for this study were extracted from an open-label prospective study, which was performed to treat new-onset T1DM patients with auto-HSCT. The 128 patients were categorized into insulin-free (IF) or insulin-dependent (ID) groups according to their response to treatment during the follow-up. We compared the baseline data of the two groups and explored possible prognostic factors and their odd ratios (ORs) with univariate analysis and multivariate logistic regression. Receiver operating characteristic curves (ROC) were performed to test the model discrimination function.. During a follow-up of 28.5 ± 8.3 months, 71 of 128 patients in the IF group discontinued insulin use, whereas 57 of 128 patients in the ID group did not decrease their insulin dose or resumed insulin treatment after a transient remission. Multivariate logistic regression analysis demonstrated that prolonged remission was positively correlated with fasting C-peptide level (OR = 2.60, 95% confidence interval [CI]: 1.16-5.85) but negatively correlated with onset age (OR = 0.36, 95% CI: 0.14-0.88) and tumor necrosis factor-α levels (OR = 0.32, 95% CI: 0.14-0.73). ROC analysis confirmed the combined predictive function of these three variables (AUC = 0.739, 95% CI: 0.655-0.824).. Age and fasting C-peptide and tumor necrosis factor-α levels were identified as possible predictors for prolonged remission following auto-HSCT therapy. Topics: Adolescent; Adult; Age Factors; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Hematopoietic Stem Cell Transplantation; Humans; Male; Multivariate Analysis; Predictive Value of Tests; Prospective Studies; Transplantation Conditioning; Transplantation, Autologous; Treatment Outcome; Tumor Necrosis Factor-alpha; Young Adult | 2015 |
THE CLINICAL AND METABOLIC CHARACTERISTICS OF YOUNG-ONSET KETOSIS-PRONE TYPE 2 DIABETES IN CHINA.
To investigate the prevalence and clinical characteristics of ketosis-prone type 2 diabetes (KPD) in Chinese patients with young-onset diabetes.. A total of 238 young diabetic patients were recruited from our inpatient department from January 1, 2012, to December 28, 2014. KPD was defined as diabetes without precipitating illness and with the presence of ketosis or diabetic ketoacidosis in the absence of autoantibodies at the time of diagnosis. We reviewed the clinical characteristics and disease progression of this group of patients.. Eighteen patients fulfilled the criteria for KPD, and the prevalence of patients with KPD was 7.6%. The mean (SD) age of the KPD group at the time of diagnosis of diabetes was 27.6 (4.85) years, and these patients were predominantly male (male to female ratio, 8:1) and had a high proportion of obesity and new-onset diabetes and a strong family history of diabetes. β-Cell function in the KPD group was intermediate between type 1 and type 2 diabetes. Patients with KPD had the highest levels of glycated hemoglobin, triglycerides, total cholesterol, and free fatty acids and the lowest levels of high-density lipoprotein. After 3 to 12 months of follow-up, 17 of 18 patients with KPD (94.4%) were able to discontinue insulin therapy, and 11 patients (61.1%) were managed with diet or exercise alone.. KPD patients accounted for 7.6% of the diabetic patients requiring admission to a large urban hospital in China, with an age of onset of diabetes of ≤35 years. These patients are more likely to be male, have abnormal lipid metabolism, and have more reversible β-cell dysfunction. Topics: Adolescent; Adult; Age of Onset; C-Peptide; China; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Humans; Male; Retrospective Studies; Young Adult | 2015 |
C-peptide: should we be testing this routinely in the Type 1 diabetes clinic?
Topics: Adolescent; Adult; Aged; Aged, 80 and over; C-Peptide; Child; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diagnostic Tests, Routine; Humans; Middle Aged; Young Adult | 2015 |
Relationship between glycaemic variability and hyperglycaemic clamp-derived functional variables in (impending) type 1 diabetes.
We examined whether measures of glycaemic variability (GV), assessed by continuous glucose monitoring (CGM) and self-monitoring of blood glucose (SMBG), can complement or replace measures of beta cell function and insulin action in detecting the progression of preclinical disease to type 1 diabetes.. Twenty-two autoantibody-positive (autoAb(+)) first-degree relatives (FDRs) of patients with type 1 diabetes who were themselves at high 5-year risk (50%) for type 1 diabetes underwent CGM, a hyperglycaemic clamp test and OGTT, and were followed for up to 31 months. Clamp variables were used to estimate beta cell function (first-phase [AUC5-10 min] and second-phase [AUC120-150 min] C-peptide release) combined with insulin resistance (glucose disposal rate; M 120-150 min). Age-matched healthy volunteers (n = 20) and individuals with recent-onset type 1 diabetes (n = 9) served as control groups.. In autoAb(+) FDRs, M 120-150 min below the 10th percentile (P10) of controls achieved 86% diagnostic efficiency in discriminating between normoglycaemic FDRs and individuals with (impending) dysglycaemia. M 120-150 min outperformed AUC5-10 min and AUC120-150 min C-peptide below P10 of controls, which were only 59-68% effective. Among GV variables, CGM above the reference range was better at detecting (impending) dysglycaemia than elevated SMBG (77-82% vs 73% efficiency). Combined CGM measures were equally efficient as M 120-150 min (86%). Daytime GV variables were inversely correlated with clamp variables, and more strongly with M 120-150 min than with AUC5-10 min or AUC120-150 min C-peptide.. CGM-derived GV and the glucose disposal rate, reflecting both insulin secretion and action, outperformed SMBG and first- or second-phase AUC C-peptide in identifying FDRs with (impending) dysglycaemia or diabetes. Our results indicate the feasibility of developing minimally invasive CGM-based criteria for close metabolic monitoring and as outcome measures in trials. Topics: Adolescent; Adult; Area Under Curve; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Glucose Tolerance Test; Glycated Hemoglobin; Healthy Volunteers; Humans; Hyperglycemia; Insulin-Secreting Cells; Male; Young Adult | 2015 |
Short-term glucagon stimulation test of C-peptide effect on glucose utilization in patients with type 1 diabetes mellitus.
This work aimed to evaluate the use of a four-point glucagon stimulation test of C-peptide effect on glucose utilization in type 1 diabetic patients using a new mathematical model. A group of 32 type 1 diabetic patients and a group of 10 healthy control subjects underwent a four-point glucagon stimulation test with blood sampling at 0, 6, 15 and 30 min after 1 mg glucagon bolus intravenous administration. Pharmacokinetic and pharmacokinetic/pharmacodynamic models of C-peptide effect on glucose utilization versus area under curve (AUC) were used. A two-sample t test and ANOVA with Bonferroni correction were used to test the significance of differences between parameters. A significant difference between control and patient groups regarding the coefficient of whole-body glucose utilization and AUC C-peptide/AUC glucose ratio (p ≪ 0.001 and p = 0.002, respectively) was observed. The high correlation (r = 0.97) between modeled coefficient of whole-body glucose utilization and numerically calculated AUC C-peptide/AUC glucose ratio related to entire cohort indicated the stability of used method. The short-term four-point glucagon stimulation test allows the numerically calculated AUC C-peptide/AUC glucose ratio and/or the coefficient of whole-body glucose utilization calculated from model to be used to diagnostically identify type 1 diabetic patients. Topics: Adult; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Humans; Male; Models, Statistical; Young Adult | 2015 |
The Pro12Ala PPARg2 gene polymorphism involves residual C-peptide secretionand BMI in type 1 diabetes.
Since insulin resistance is genetically determined and observed in type 1 diabetes, the study was designed to elucidate an involvement of Ala 12 Pro PPARg2 gene polymorphism in residual C-peptide secretion and BMI variation in children with type 1 diabetes.. In 103 patients with type 1 diabetes genetic analysis of PPARg2 polymorphism, C-peptide measurements and evaluation of BMI and clinical parameters were performed. Control group consisted of 109 healthy subjects.. In diabetic patients, only three individuals exhibited Ala 12 Ala genotype (2.9%) and 29 patients were heterozygous Ala 12 Pro (28.2%). Interestingly, Ala12+ variants were associated with higher C-peptide levels in 6 th , 12 th and 24 th months after the onset than Pro 12 Pro genotype (0.39±0.24 pmol/mL vs. 0.22±0.14 pmol/mL, P=0.007 and 0.19±0.09 vs. 0.11±0.07, P=0.01 and 0.13±0.09 vs. 0.07±0.05, P=0.021, respectively). Similarly, C-peptide was also significantly increased in patients with history of type 2 diabetes in the first-degree relatives. The observation was even more evident when Ala12+ variants were taken together with family history of type 2 diabetes. Besides, in 24 th and 36 th months after the onset, Ala12+ variants revealed to be associated with higher BMI normalized by age and sex as compared to Pro 12 Pro (0.557±0.84 vs. -0.119±0.73, P=0.001 and 0.589±0.919 vs. 0.066±0.630, P=0.016, respectively).. Thus, it is likely that PPARg2 gene polymorphism and/or the genetically determined insulin resistance may be associated with residual C-peptide secretion and involve excessive BMI in type 1 diabetes.. Wprowadzenie i cel pracy. Z uwagi na występowanie w cukrzycy typu 1 (T1D) zjawiska insulinooporności oraz możliwość jej genetycznego uwarunkowania celem pracy była ocena wpływu polimorfizmu Ala 12 Pro genu PPARg2 na resztkową insulinosekrecję mierzoną stężeniem peptydu C oraz zmiany wartości indeks BMI u dzieci z cukrzycą typu 1. Materiał i metody. W grupie 103 pacjentów z T1D została przeprowadzona analiza genetyczna polimorfizmu genu PPARg2, pomiary stężenia peptydu C oraz ocena indeksu BMI i parametrów klinicznych. Grupa kontrolna obejmowała 109 zdrowe osoby. Wyniki. U pacjentów z T1D jedynie 3 dzieci posiadało genotyp Ala 12 Ala (2.9%), podczas gdy 29 pacjentów było heterozygotami Ala 12 Pro (28.2%). Interesujące, że warianty Ala12+ były związane z wyższym stężeniem peptydu C w 6, 12 oraz 24 miesiącu trwania choroby w porównaniu z genotypem Pro 12 Pro (0.39±0.24 pmol/mL vs. 0.22±0.14 pmol/mL, P=0.007 i 0.19±0.09 vs. 0.11±0.07, P=0.01 oraz 0.13±0.09 vs. 0.07±0.05, P=0.021, odpowiednio). Podobnie stężenie peptydu C było istotnie wyższe u pacjentów z dodatnim wywiadem w kierunku cukrzycy typu 2 u krewnych pierwszego stopnia. Obserwacja ta była jeszcze bardziej wyraźna, gdy warianty Ala12 + były oceniane łącznie z rodzinnym wywiadem cukrzycy typu 2. Ponadto pacjenci, u których stwierdzono warianty Ala12+ charakteryzowali się w 24 i 36 miesiącu trwania cukrzycy wyższym indeksem BMI znormalizowanym pod względem płci i wieku w porównaniu do nosicieli Pro 12 Pro (0.557±0.84 vs. -0.119±0.73, P=0.001 i 0.589±0.919 vs. 0.066±0.630, P=0.016, odpowiednio). Wnioski. Wydaje się prawdopodobne, że polimorfizm genu PPARg2 i/lub genetycznie uwarunkowana insulinooporność mogą być związane z resztkową insulinosekrecją oraz wzrostem BMI w cukrzycy typu 1 u dzieci. Topics: Adolescent; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Humans; Insulin Resistance; Male; Obesity; Poland; Polymorphism, Genetic; PPAR gamma; Risk Factors | 2015 |
Fetal Pancreatic Stem-Cell Transplant in Patients With Diabetes Mellitus.
To determine the efficacy of fetal stem cell transplant for treating patients with diabetes mellitus types 1 and 2.. Five patients with diabetes mellitus type 1 and 5 patients with diabetes mellitus type 2 (aged 18-56 years) received a fetal pancreatic stem-cell transplant (cells were 16-18 wk gestation) performed by intravenous infusion at 50 mL/hour. The quantity of fetal stem cells infused was ≥ 5-8*106. We analyzed the patients' C-peptide and glycated hemoglobin levels both before and 3 months after fetal stem cell transplant.. In patients with diabetes mellitus type 1, fetal stem-cell transplant led to a significant increase in C-peptide levels, from 0.09 ± 0.01 ng/mL to 0.20 ± 0.07 ng/mL, after 3 months (P < .008).. Treatment with fetal pancreatic stem cells may be beneficial for treating patients with type 1 or type 2 diabetes. Topics: Adolescent; Adult; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Fetal Stem Cells; Glycated Hemoglobin; Humans; Male; Middle Aged; Pancreas Transplantation; Stem Cell Transplantation; Time Factors; Treatment Outcome; Young Adult | 2015 |
[Clinical features of non-alcoholic fatty liver disease and its relationship with serum C-peptide levels in patients with latent autoimmune diabetes in adults].
To investigate the clinical features of non-alcoholic fatty liver disease (NAFLD) and its relationship with serum C-peptide levels in patients with latent autoimmune diabetes in adults (LADA).. A total of 155 patients with LADA who had no drinking history and were hospitalized in department of endocrinology and metabolism from January 2007 to June 2009 were divided into two groups, including patients with LADA but without NAFLD and patients with both LADA and NAFLD, according to Chinese medical association's guidelines of NAFLD and hepatic ultrasound result. Their clinical data and results of laboratory examinations were collected and analyzed, including medications, blood pressure, weight, height, waist circumference, hip circumference, fasting plasma glucose, 2 h postprandial plasma glucose, fasting C-peptide, 2 h postprandial C-peptide, hemoglobin A1c, renal function, liver function, blood lipid and C-reactive protein. The clinical features between two groups were compared and the relationship between serum C-peptide and NAFLD were also analyzed.. Compared to the patients with LADA but without NAFLD, patients with both LADA and NAFLD had higher alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (γ-GT) (all P<0.01), but the serum total bilirubin (TBI) and direct bilirubin (DBI) level had no significant inter-group difference (P>0.05). The patients with both LADA and NAFLD had higher fasting C-peptide [0.62(0.33-0.93) vs 0.17 (0.05-0.50) nmol/L, P<0.001], 2 h postprandial C-peptide [1.57(0.78-1.88) vs 0.42(0.06-1.01) nmol/L, P<0.001] and more severe insulin resistance [0.8(1.0-2.5) vs 0.6(0.2-1.3), P<0.001]. Logistic regression analysis showed that there was a significant association between fasting C-peptide and the presence of NAFLD after controlling other confounding factors in patients with LADA.. The patients with both LADA and NAFLD had more severe metabolic disorders and insulin resistance. Serum fasting C peptide was independently associated with the presence of NAFLD in patients with LADA. Topics: Adult; Alanine Transaminase; Asian People; Aspartate Aminotransferases; C-Peptide; C-Reactive Protein; Diabetes Mellitus, Type 1; gamma-Glutamyltransferase; Glucose Intolerance; Glycated Hemoglobin; Humans; Insulin Resistance; Non-alcoholic Fatty Liver Disease; Waist Circumference | 2015 |
Should diabetic ketosis without acidosis be included in ketosis-prone type 2 diabetes mellitus?
The incidence of ketosis-prone type 2 diabetes is very low except for people of sub-Saharan African origin and African Americans. However, there also are some type 2 diabetes patients with diabetic ketosis without acidosis (DKWA). We question whether DKWA should be included as a subtype of ketosis-prone type 2 diabetes mellitus and compared the clinical characteristics of DKWA and diabetic ketoacidosis (DKA) patients.. The study population consisted of 594 consecutive unrelated Chinese inpatients with newly diagnosed type 2 diabetes. Demographic and clinical characteristics (age, gender, family history of diabetes, body mass index, blood pressure and plasma lipid parameters) were recorded. The patients were divided into ketosis-resistant diabetes (KRD), DKWA and DKA groups on the basis of urinary ketones, blood pH and bicarbonate levels. The blood glucose and c-peptide levels of the patients were also evaluated.. The prevalence of KRD, DKWA and DKA were 78.33%, 19.72% and 1.95%, respectively, in the study population. The clinical characteristics of patients with DKWA group patients were similar to those with DKA, except that DKA patients had higher blood glucose and deteriorated β cell function.. Diabetic ketosis without acidosis and DKA patients share similar clinical characteristics; DKWA should be considered ketosis-prone type 2 diabetes. Therefore, the prevalence of ketosis-prone type 2 diabetes might be underestimated. Topics: Acidosis; Adult; Blood Glucose; C-Peptide; China; Comorbidity; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Humans; Incidence; Male; Middle Aged; Prevalence; Sex Distribution; Sex Factors | 2014 |
Increased circulating levels of betatrophin in individuals with long-standing type 1 diabetes.
The hormone betatrophin was recently described as a potent stimulator of beta cell proliferation in mice. Insulin resistance, but not insulin deficiency, caused upregulation of betatrophin expression. If these findings were found to be fully applicable in humans, this would open up the possibility of future betatrophin treatment in type 1 diabetes. The present study measured for the first time betatrophin concentrations in humans and tested the hypothesis that there would be no difference in circulating betatrophin concentrations between patients with type 1 diabetes and healthy individuals.. Betatrophin concentrations in plasma of 33 patients with type 1 diabetes and 24 age-matched healthy controls were measured by ELISA. The study participants were characterised for blood lipids, BMI, plasma glucose and HbA1c, and, for the diabetic patients, their insulin requirements and any residual C-peptide concentrations.. Plasma betatrophin concentrations were normally ~300 pg/ml, but were approximately doubled in patients with type 1 diabetes. In the patients, there were no correlations between betatrophin and age, blood lipids, BMI, glucose control or insulin requirement, whereas in controls betatrophin levels increased with age. BMI, blood pressure and triacylglycerol, LDL-cholesterol and HDL-cholesterol levels were similar in patients and healthy controls.. Circulating concentrations of betatrophin are increased in type 1 diabetes in contrast with what was recently described in an insulin-deficient mouse model. However, increased betatrophin concentrations do not protect against loss of C-peptide. Betatrophin treatment in type 1 diabetes would therefore probably not be successful without the use of supraphysiological doses or a combination with immune regulatory treatment. Topics: Adult; Angiopoietin-Like Protein 8; Angiopoietin-like Proteins; C-Peptide; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Peptide Hormones; Young Adult | 2014 |
General immune dampening is associated with disturbed metabolism at diagnosis of type 1 diabetes.
Type 1 diabetes (T1D) is a serious diagnosis with the prospect of grave short- and long-term complications and even death if poorly managed. An attempt has been made to describe how clinical and immunological deviations might influence each other close to the diagnosis of T1D.. Sixty-nine newly diagnosed T1D children were studied together with a reference group of 30 healthy children. Cytokines (interleukin (IL)-6, IL-10, IL-13, IL-17, interferon-γ, and tumor necrosis factor-α) were detected in in vitro culture by multiplex fluorochrome technique. Information of clinical status of the patients such as BMI, weight loss, pubertal stage, duration of symptoms, previous and/or ongoing infections, insulin requirement, and ketoacidosis were gathered together with the analysis of C-peptide and glycosylated hemoglobin (HbA1c).. In general, low cytokine secretion was found at diagnosis of T1D. However, high C-peptide, short duration of symptoms, or an infection prior to diagnosis was associated with increased immune activity including proinflammatory, Th2-associated, and Tr1-associated cytokines. In contrast, ketoacidosis and later pubertal stage at onset of disease were more related to a Th1-prone response.. There is a general immune dampening at diagnosis of T1D, which appears to be related to the metabolic state close to diagnosis. Topics: Adolescent; Autoantigens; C-Peptide; Child; Cytokines; Diabetes Mellitus, Type 1; Humans; Ketosis; Puberty | 2014 |
Age-dependent decline of β-cell function in type 1 diabetes after diagnosis: a multi-centre longitudinal study.
C-peptide secretion is currently the only available clinical biomarker to measure residual β-cell function in type 1 diabetes. However, the natural history of C-peptide decline after diagnosis can vary considerably dependent upon several variables. We investigated the shape of C-peptide decline over time from type 1 diabetes onset in relation to age at diagnosis, haemoglobin A1c (HbA1c) levels and insulin dose.. We analysed data from 3929 type 1 diabetes patients recruited from seven European centres representing all age groups at disease onset (childhood, adolescence and adulthood). The influence of the age at onset on β-cell function was investigated in a longitudinal analysis at diagnosis and up to 5-years follow-up.. Fasting C-peptide (FCP) data at diagnosis were available in 3668 patients stratified according to age at diagnosis in four groups (<5 years, n = 344; >5 years < 10 years, n = 668; >10 years < 18 years, n = 991; >18 years, n = 1655). FCP levels were positively correlated with age (p < 0.001); the subsequent decline in FCP over time was log-linear with a greater decline rate in younger age groups (p < 0.0001).. This study reveals a positive correlation between age at diagnosis of type 1 diabetes and FCP with a more rapid decline of β-cell function in the very young patients. These data can inform the design of clinical trials using C-peptide values as an end-point for the effect of a given treatment. Topics: Adolescent; Adult; Age Factors; Age of Onset; Aging; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Europe; Fasting; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Insulin; Insulin Antibodies; Insulin-Secreting Cells; Longitudinal Studies; Male | 2014 |
The majority of patients with long-duration type 1 diabetes are insulin microsecretors and have functioning beta cells.
Classically, type 1 diabetes is thought to proceed to absolute insulin deficiency. Recently developed ultrasensitive assays capable of detecting C-peptide under 5 pmol/l now allow very low levels of C-peptide to be detected in patients with long-standing type 1 diabetes. It is not known whether this low-level endogenous insulin secretion responds to physiological stimuli. We aimed to assess how commonly low-level detectable C-peptide occurs in long-duration type 1 diabetes and whether it responds to a meal stimulus.. We performed a mixed-meal tolerance test in 74 volunteers with long-duration (>5 years) type 1 diabetes, i.e. with age at diagnosis 16 (9-23) years (median [interquartile range]) and diabetes duration of 30 (19-41) years. We assessed fasting and stimulated serum C-peptide levels using an electrochemiluminescence assay (detection limit 3.3 pmol/l), and also the urinary C-peptide:creatinine ratio (UCPCR).. Post-stimulation serum C-peptide was detectable at very low levels (>3.3 pmol/l) in 54 of 74 (73%) patients. In all patients with detectable serum C-peptide, C-peptide either increased (n = 43, 80%) or stayed the same (n = 11) in response to a meal, with no indication of levels falling (p < 0.0001). With increasing disease duration, absolute C-peptide levels fell although the numbers with detectable C-peptide remained high (68%, i.e. 25 of 37 patients with >30 years duration). Similar results were obtained for UCPCR.. Most patients with long-duration type 1 diabetes continue to secrete very low levels of endogenous insulin, which increase after meals. This is consistent with the presence of a small number of still functional beta cells and implies that beta cells are either escaping immune attack or undergoing regeneration. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Young Adult | 2014 |
Plasma concentrations of soluble IL-2 receptor α (CD25) are increased in type 1 diabetes and associated with reduced C-peptide levels in young patients.
Type 1 diabetes is a common autoimmune disease that has genetic and environmental determinants. Variations within the IL2 and IL2RA (also known as CD25) gene regions are associated with disease risk, and variation in expression or function of these proteins is likely to be causal. We aimed to investigate if circulating concentrations of the soluble form of CD25, sCD25, an established marker of immune activation and inflammation, were increased in individuals with type 1 diabetes and if this was associated with the concentration of C-peptide, a measure of insulin production that reflects the degree of autoimmune destruction of the insulin-producing beta cells.. We used immunoassays to measure sCD25 and C-peptide in peripheral blood plasma from patient and control samples.. We identified that sCD25 was increased in patients with type 1 diabetes compared with controls and replicated this result in an independent set of 86 adult patient and 80 age-matched control samples (p = 1.17 × 10(-3)). In 230 patients under 20 years of age, with median duration-of-disease of 6.1 years, concentrations of sCD25 were negatively associated with C-peptide concentrations (p = 4.8 × 10(-3)).. The 25% increase in sCD25 in patients, alongside the inverse association between sCD25 and C-peptide, probably reflect the adverse effects of an on-going, actively autoimmune and inflammatory immune system on beta cell function in patients. Topics: Adolescent; Adult; Aged; Biomarkers; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Disease Progression; Female; Humans; Immunoassay; Inflammation; Insulin-Secreting Cells; Interleukin-2 Receptor alpha Subunit; Male; Middle Aged | 2014 |
The diabetes control and complications trial/epidemiology of diabetes interventions and complications study at 30 years: summary and future directions.
OBJECTIVE The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study continues to address knowledge gaps in our understanding of type 1 diabetes and the effects of intensive therapy on its long-term complications. RESEARCH DESIGN AND METHODS During the DCCT (1982-1993), a controlled clinical trial of 1,441 subjects with type 1 diabetes, and the EDIC (1994-present), an observational study of the DCCT cohort, core data collection has included medical history questionnaires, surveillance health exams, and frequent laboratory and other evaluations for microvascular and macrovascular disease. Numerous collaborations have expanded the outcome data with more detailed investigations of cardiovascular disease, cognitive function, neuropathy, genetics, and potential biological pathways involved in the development of complications. RESULTS The longitudinal follow-up of the DCCT/EDIC cohort provides the opportunity to continue monitoring the durability of intensive treatment as well as to address lingering questions in type 1 diabetes research. Future planned analyses will address the onset and progression of microvascular triopathy, evidence-based screening for retinopathy and nephropathy, effects of glycemic variability and nonglycemic risk factors on outcomes, long-term impact of intensive therapy on cognitive decline, and health economics. Three new proposed investigations include an examination of residual C-peptide secretion and its impact, prevalence of hearing impairment, and evaluation of gastrointestinal dysfunction. CONCLUSIONS With the comprehensive data collection and the remarkable participant retention over 30 years, the DCCT/EDIC continues as an irreplaceable resource for understanding type 1 diabetes and its long-term complications. Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Gastrointestinal Diseases; Glycated Hemoglobin; Hearing Disorders; Humans; Insulin; Male; Mass Screening; Middle Aged; Randomized Controlled Trials as Topic; Translational Research, Biomedical; Treatment Outcome; United States; Young Adult | 2014 |
Obestatin levels are associated with C-peptide and antiinsulin antibodies at the onset, whereas unacylated and acylated ghrelin levels are not predictive of long-term metabolic control in children with type 1 diabetes.
Ghrelin secretion is altered at the onset and after the start of insulin therapy in children with type 1 diabetes. Contemporary regulation of acylated ghrelin (AG), unacylated ghrelin (UAG), and obestatin (OBST) remains undefined in this disease. It is unknown as to whether they could be good predictors of changes in glucose and metabolic control.. This was a longitudinal study conducted in a tertiary care center. AG, UAG, and OBST were measured at baseline and after 2 years of follow-up in 51 children and adolescents with a history of type 1 diabetes extending beyond 1 year. A total of 33 healthy matched subjects were used as controls.. Age-, puberty-, and body mass index-adjusted UAG levels were lower (P < .005) and OBST levels were higher (P < .009) in children with type 1 diabetes, with respect to controls. AG levels were similar to controls, but all ratios of the three peptides are altered in diabetic patients. OBST (P < .05) was negatively correlated with C-peptide (P < .05) and insulin antibodies (P < .008) at the onset of diabetes. In diabetic patients, baseline AG and UAG levels were negatively correlated with insulin dosage in the short and long term (P < .001). AG, but not OBST, was positively correlated with C-peptide levels 2 years after diagnosis (P < .05). Overall, the peptides were not predictive of glucose and metabolic control.. UAG, AG, OBST, and their ratios are differently regulated in children with type 1 diabetes, suggesting a role in the metabolic balance of the disease, with insulin a likely regulator of AG and UAG. The peptides do not appear to be good long-term predictors of glucose control, with further investigations needed to explain whether OBST could be a precocious predictor of islet dysfunction. Topics: Acetylation; Adolescent; Autoantibodies; C-Peptide; Case-Control Studies; Child; Diabetes Mellitus, Type 1; Female; Ghrelin; Humans; Insulin; Male; Prognosis | 2014 |
Administering 25-hydroxyvitamin D3 in vitamin D-deficient young type 1A diabetic patients reduces reactivity against islet autoantigens.
We investigated whether improving 25-hydroxyvitamin D status in young type 1A diabetic patients reduces reactivity of peripheral blood mononuclear cells against islet autoantigens and associates with beta-cell functional changes.. Eight patients with 25-hydroxyvitamin D deficiency (<20 ng/ml), out of 15 consecutive young type 1A diabetic subjects received 25-hydroxyvitamin D3 to achieve and maintain levels above 50 ng/ml for up to one year. Peripheral blood mononuclear cell reactivity (Interferon-γ spots) against beta-cell autoantigens (glutamic acid decarboxylase 65-kD isoform, proinsulin and tyrosine phosphatase-like protein IA-2) and C-peptide during mixed meal were assessed before and after 25-hydroxyvitamin D3 replenishment.. Target 25-hydroxyvitamin D blood levels were safely reached and maintained. Peripheral blood mononuclear cell reactivity against glutamic acid decarboxylase 65-kD isoform (3.8 ± 4.0 vs. 45 ± 16) and proinsulin (3.5 ± 3.2 vs. 75 ± 51) decreased significantly (p < 0.001 and p < 0.02) upon 25-hydroxyvitamin D3 replenishment, which was correlated with 25-hydroxyvitamin D concentrations. C-peptide values remained stable after one year of treatment.. Safely restored and maintained 25-hydroxyvitamin D levels associated with reduced peripheral blood mononuclear cell reactivity against beta-cell autoantigens with no significant decrease of beta-cell function in this cohort of patients. Topics: Adolescent; Autoantigens; C-Peptide; Calcifediol; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Insulin-Secreting Cells; Interferon-gamma; Leukocytes, Mononuclear; Male; Proinsulin; Vitamin D Deficiency | 2014 |
Neonatal and infant beta cell hormone concentrations in relation to type 1 diabetes risk.
Type 1 diabetes is preceded by the appearance of islet autoantibodies. Seroconversion to islet autoantibodies is greatest around 1 yr of age and is more frequent in children born to fathers with type 1 diabetes as compared to children born to mothers with type 1 diabetes. Here we asked whether changes in beta-cell function in the neonate and infant reflect variations in the incidence of islet autoantibody seroconversion. Insulin, proinsulin, and c-peptide concentrations were measured in sequential samples taken from birth to age 2 yr in 103 children who had a first degree relative with type 1 diabetes and who had been followed for islet autoantibody seroconversion. Serum insulin and proinsulin concentrations were highest at birth declining by age 3 months and stable thereafter until age 2 yr. C-peptide concentrations, proinsulin/insulin, and proinsulin/c-peptide ratios were stable from age 3 months. No differences were observed between children who developed islet autoantibodies and children who remained islet autoantibody negative. Children born to a mother with type 1 diabetes had higher birth concentrations of insulin (p = 0.005) and proinsulin (p = 0.014) as compared with children of non-diabetic mothers. Increased insulin concentrations in children of type 1 diabetes mothers persisted until age 6 months. In conclusion, we could not relate excursions in beta-cell hormones to autoantibody development, but suggest that the higher exposure to insulin and proinsulin in neonates born to mothers with type 1 diabetes may be linked to the relative protection against islet autoantibody seroconversion observed in these children. Topics: Autoantibodies; Autoimmunity; C-Peptide; Child Development; Diabetes Mellitus, Type 1; Female; Fetal Development; Germany; Humans; Incidence; Infant; Infant, Newborn; Insulin; Insulin Secretion; Insulin-Secreting Cells; Longitudinal Studies; Male; Maternal-Fetal Exchange; Pregnancy; Pregnancy in Diabetics; Proinsulin; Risk | 2014 |
Home urine C-peptide creatinine ratio can be used to monitor islet transplant function.
Islet graft function is defined by serum C-peptide in a standardized challenge test. We assessed whether urine C-peptide creatinine ratio (UCPCR) sent from home could provide a viable alternative.. Seventeen islet recipients provided 90-min serum C-peptide (sCP90) and 120-min UCPCR (UCPCR120) samples during 68 interval posttransplant mixed-meal tolerance tests, also posting from home a 120-min postbreakfast UCPCR sample every 2 weeks. UCPCR was compared with a clinical score of islet function, derived from HbA1c and insulin dose.. UCPCR120 and mean home postmeal UCPCR were strongly correlated with sCP90 (r(s) = 0.73, P < 0.001; and rs = 0.73, P < 0.01, respectively). Mean home UCPCR increased with clinical score (r(s) = 0.75; P < 0.001) and with graft function defined both by sCP90 >200 pmol/L and insulin independence. UCPCR cutoffs to detect insulin independence and poor graft function were sensitive and specific.. Home UCPCR provides a valid measure of C-peptide production in islet transplant recipients. Topics: Aged; Biomarkers; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Graft Survival; Humans; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Monitoring, Physiologic; Prognosis; Prospective Studies | 2014 |
Tmem27 is upregulated by vitamin D in INS-1 cells and its serum concentrations are low in patients with autoimmune diabetes.
Transmembrane protein 27 (Tmem27), which is expressed in pancreatic β-cells, plays an important role in insulin secretion and pancreatic β-cell proliferation. Analysis of the INS-1 cell proteome using stable isotope labeling by amino acids in cell culture (SILAC) in combination with LC-MS identified Tmem27 as the one of most robustly (up to seven-fold) upregulated proteins after treatment with the active metabolite of vitamin D, 1,25-(OH)2D3. Furthermore, we report that Tmem27 which is cleaved and released from, i.e. pancreatic β-cells, is present in human serum and its levels are significantly lower in subjects with autoimmune diabetes as compared to healthy individuals (13% of the levels). Additionally, Tmem27 correlated positively (0.70) with C-peptide serum levels in healthy subjects. Our data indicate that Tmem27 could be of potential value as a serum marker for the pathogenesis of diabetes and as such may warrant the development of measurement methods with lower limit of detection for its further validation. Topics: Animals; Biomarkers; C-Peptide; Calcitriol; Case-Control Studies; Cell Line; Diabetes Mellitus, Type 1; Female; Humans; Insulin-Secreting Cells; Male; Membrane Glycoproteins; Rats; Up-Regulation; Vitamin D | 2014 |
Recommendations for the definition of clinical responder in insulin preservation studies.
Clinical responder studies should contribute to the translation of effective treatments and interventions to the clinic. Since ultimately this translation will involve regulatory approval, we recommend that clinical trials prespecify a responder definition that can be assessed against the requirements and suggestions of regulatory agencies. In this article, we propose a clinical responder definition to specifically assist researchers and regulatory agencies in interpreting the clinical importance of statistically significant findings for studies of interventions intended to preserve β-cell function in newly diagnosed type 1 diabetes. We focus on studies of 6-month β-cell preservation in type 1 diabetes as measured by 2-h-stimulated C-peptide. We introduce criteria (bias, reliability, and external validity) for the assessment of responder definitions to ensure they meet U.S. Food and Drug Administration and European Medicines Agency guidelines. Using data from several published TrialNet studies, we evaluate our definition (no decrease in C-peptide) against published alternatives and determine that our definition has minimum bias with external validity. We observe that reliability could be improved by using changes in C-peptide later than 6 months beyond baseline. In sum, to support efficacy claims of β-cell preservation therapies in type 1 diabetes submitted to U.S. and European regulatory agencies, we recommend use of our definition. Topics: Adolescent; Bias; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Reproducibility of Results; Treatment Outcome | 2014 |
Disease progression among 446 children with newly diagnosed type 1 diabetes located in Scandinavia, Europe, and North America during the last 27 yr.
To clarify whether the rate of decline in stimulated C-peptide (SCP) from 2 to 15 months after diagnosis has changed over an interval of 27 yr.. The rate of decline in SCP levels at 1, 2, 3, 6, 9, 12, and 15 months after diagnosis was compared in four paediatric cohorts from Scandinavian and European countries including 446 children with new onset type 1 diabetes (T1D, 1982-2004). Findings were evaluated against 78 children (2004-2009) from the TrialNet studies.. The mean rate of decline [%/month (±SEM)] in SCP for a 10-yr-old child was 7.7%/month (±1.5) in the 1982-1985 Cohort, 6.3%/month (±1.7) in the 1995-1998 Cohort, 7.8%/month (±0.7) in the 1999-2000 Cohort, and 10.7%/month (±0.9) in the latest 2004-2005 Cohort (p = 0.05). Including the TrialNet Cohort with a rate of decline in SCP of 10.0%/month (±0.9) the differences between the cohorts are still significant (p = 0.039). The rate of decline in SCP was negatively associated with age (p < 0.0001), insulin antibodies (IA) (p = 0.003), and glutamic acid decarboxylase-65 (GAD65A) (p = 0.03) initially with no statistically significant effect of body mass index (BMI) Z-score at 3 months. Also, at 3 months the time around partial remission, the effect of age on SCP was significantly greater in children ≤5 yr compared with older children (p ≤ 0.0001).. During the past 27 yr, initial C-peptide as well as the rate of C-peptide decline seem to have increased. The rate of decline was affected significantly by age, GAD65A, and IA, but not BMI Z-score or initial C-peptide. Topics: Body Mass Index; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Disease Progression; Europe; Female; Glutamate Decarboxylase; Humans; Infant; Insulin Antibodies; Male; North America; Scandinavian and Nordic Countries; White People | 2014 |
Utility of glucagon stimulation test in type 1 diabetes after pancreas transplantation.
Despite recent progress of immunosuppressive therapy with newly developed agents, long-term pancreatic graft survival after pancreas transplantation still remains low. Therefore, precise assessment of β-cell function after pancreas transplantation is necessary.. Pancreatic β-cell secretory activity was measured by means of the peripheral plasma fasting serum C-peptide (CPR) response to 1 mg of glucagon intravenously in 23 patients after pancreas transplantation. The utility of ΔCPR after injection was compared with other indices that reflect insulin secretion.. When we performed the test, 6 patients still needed insulin injection after the transplantation. Mean CPR before and after glucagon intravenously were 1.9 ± 0.98 ng/mL and 4.6 ± 2.29 ng/mL, respectively. Fasting serum CPR, secretory unit of islet in transplantation (SUIT) index, and ΔCPR after glucagon injection were significantly different between insulin users and nonusers. During follow-up (501 ± 228 days), 3 patients could stop using insulin, and their increase of CPR (1.8 ± 0.5 ng/mL) was significantly higher than that in continuous insulin users (0.3 ± 0.3 ng/mL).. Fasting CPR, SUIT index, and ΔCPR after glucagon injection could reflect β-cell function for post-pancreas transplant patients, and glucagon stimulation test could give us additional information to predict insulin-free treatment. Topics: C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Humans; Insulin; Pancreas Transplantation | 2014 |
[Difficult diagnosis in a 17-year-old patient: Type 1 diabetes? Type 2 diabetes? Or "double diabetes"?].
MEDICAL HISTORY AND CLINICAL FINDINGS: We report on a 17-year-old boy with elevated blood glucose levels, elevated liver enzymes and obesity (BMI 32.3 kg/m2). Clinical examination showed acanthosis nigricans and a vitiligo. The rest of the physical examination was without pathological findings.. The HbA1c value was 8.6 % (71 mmol/mol), and postprandial C-peptide showed a maximum level of 1.3 nmol/l. The type 1 diabetes-associated autoantibodies against protein tyrosine phosphatase IA-2 and zinc-transporter-8 were positive, while autoantibodies to glutamic acid decarboxylase and insulin were negative. There was no ketonuria. Ultrasound showed steatohepatitis.. Under therapy with metformin up to 2×1 g, blood glucose levels and liver enzymes normalized after a few weeks. After two months, the HbA1c value was 6.0 % (42.1 mmol/mol), and a weight loss of 5 kg was recorded.. In obese adolescent patients with diabetes, a clear classification right from the beginning is not always possible. Characteristic findings of type 1 and type 2 diabetes may be present simultaneously. In the presented patient, monotherapy with metformin was sufficient in the first year. Close monitoring is essential to detect the transition to insulin dependence in time. Topics: Adolescent; Autoantibodies; Blood Glucose; C-Peptide; Cation Transport Proteins; Comorbidity; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Male; Metformin; Pediatric Obesity; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Zinc Transporter 8 | 2014 |
Serum insulin-like growth factor-binding protein-3 level correlated with glycemic control and lipid profiles in children and adolescents with type 1 diabetes.
Increasing evidence suggests a role of the IGF axis in the maintenance of normal glucose and lipid metabolism. The local IGF-IGFBP environment changes significantly in response to the diabetes milieu. We aimed at determining serum IGF-1 and IGFBP-3 levels in children with type 1 diabetes mellitus (T1DM) and their relationship with clinical variables. Seventy-eight patients with T1DM and 47 healthy control subjects were included in this study. Significant reduction for concentration of serum IGF-1 was observed in patients with T1DM compared to healthy controls. However, serum IGFBP-3 levels were similar in patients with T1DM compared to controls. Both serum IGF-1 and IGFBP-3 levels were significantly correlated with age, BMI, and serum c-peptide levels. In addition, serum IGFBP-3 levels showed significant positive correlation with HbA1c, total cholesterol, and LDL-cholesterol in the uncontrolled diabetic patients. These findings suggest that IGFBP-3 may be involved in the glucose control and lipid metabolism in those with uncontrolled T1DM. Further studies are needed to document their roles on glucose and lipid metabolism in T1DM. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin-Like Growth Factor Binding Protein 3; Insulin-Like Growth Factor I; Lipid Metabolism; Lipids; Male | 2014 |
CD226 rs763361 is associated with the susceptibility to type 1 diabetes and greater frequency of GAD65 autoantibody in a Brazilian cohort.
CD226 rs763361 variant increases susceptibility to type 1 diabetes (T1D) in Caucasians. There is no data about CD226 variants in the very heterogeneous Brazilian population bearing a wide degree of admixture. We investigated its association with T1D susceptibility, clinical phenotypes, and autoimmune manifestations (islet and extrapancreatic autoantibodies). Casuistry. 532 T1D patients and 594 controls in a case-control study. Initially, CD226 coding regions and boundaries were sequenced in a subset of 106 T1D patients and 102 controls. In a second step, two CD226 variants, rs763361 (exon 7) and rs727088 (3' UTR region), involved with CD226 regulation, were genotyped in the entire cohort. C-peptide and autoantibody levels were determined. No new polymorphic variant was found. The variants rs763361 and rs727088 were in strong linkage disequilibrium. The TT genotype of rs763361 was associated with TID risk (OR = 1.503; 95% CI = 1.135-1.991; P = 0.0044), mainly in females (P = 0.0012), greater frequency of anti-GAD autoantibody (31.9% × 24.5%; OR = 1.57; CI = 1.136-2.194; P = 0.0081), and lower C-peptide levels when compared to those with TC + CC genotypes (0.41 ± 0.30 ng/dL versus 0.70 ± 0.53 ng/dL P = 0.0218). Conclusions. The rs763361 variant of CD226 gene (TT genotype) was associated with susceptibility to T1D and with the degree of aggressiveness of the disease in T1D patients from Brazil. Ancestry had no effect. Topics: 3' Untranslated Regions; Adolescent; Adult; Antigens, Differentiation, T-Lymphocyte; Autoantibodies; Brazil; C-Peptide; Case-Control Studies; Child; Cohort Studies; Diabetes Mellitus, Type 1; Exons; Female; Genetic Predisposition to Disease; Genotype; Glutamate Decarboxylase; Humans; Male; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Young Adult | 2014 |
No evidence of viral transmission following long-term implantation of agarose encapsulated porcine islets in diabetic dogs.
We have previously described the use of a double coated agarose-agarose porcine islet macrobead for the treatment of type I diabetes mellitus. In the current study, the long-term viral safety of macrobead implantation into pancreatectomized diabetic dogs treated with pravastatin (n = 3) was assessed while 2 dogs served as nonimplanted controls. A more gradual return to preimplant insulin requirements occurred after a 2nd implant procedure (days 148, 189, and >652) when compared to a first macrobead implantation (days 9, 21, and 21) in all macrobead implanted animals. In all three implanted dogs, porcine C-peptide was detected in the blood for at least 10 days following the first implant and for at least 26 days following the second implant. C-peptide was also present in the peritoneal fluid of all three implanted dogs at 6 months after 2nd implant and in 2 of 3 dogs at necropsy. Prescreening results of islet macrobeads and culture media prior to transplantation were negative for 13 viruses. No evidence of PERV or other viral transmission was found throughout the study. This study demonstrates that the long-term (2.4 years) implantation of agarose-agarose encapsulated porcine islets is a safe procedure in a large animal model of type I diabetes mellitus. Topics: Animals; Body Weight; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Dogs; Insulin; Islets of Langerhans; Male; Pravastatin; Sepharose; Swine; Time Factors | 2014 |
Circulating immune mediators are closely linked in adult-onset type 1 diabetes as well as in non-diabetic subjects.
Relationships between circulating immune mediators (cytokines, chemokines and growth factors) and a beta cell destructive autoimmune process in adult-onset type 1 diabetes are poorly elucidated. We measured serum levels of immune mediators in type 1 diabetic patients in the context of ongoing deterioration of endogenous insulin secretion. Levels of 27 immune mediators were measured in 34 GADA (glutamic acid decarboxylase antibodies) positive type 1 diabetic patients, aged 27.4 ± 1.2 years at a mean of 7 weeks after diagnosis (designated 0 month) and 6 months later. Endogenous insulin secretion was assessed by C-peptide glucagon stimulation tests during 12 months. Additional data (for baseline analysis) was obtained in 9 GADA positive type 1 diabetic subjects and in 43 non-diabetic age- and sex-matched subjects. In general, the levels of immune mediators displayed large inter- but small intra-individual differences with only minor changes observed between measurements at 0 month and at 6 months. Levels of the majority of immune mediators were strongly and positively correlated to each other not only in the diabetic, but also in the non-diabetic subjects. Body weight (BMI) was positively associated with levels of IL-1 ra, IL-2, IL-4, IL-6, IL-17, Basic FGF, GCSF, IFN gamma and MIP-1 alpha. Adjustment for BMI removed most associations to C-peptide. When adjusted for BMI, levels at 0 month for Basic FGF and MIP-1 alpha were inversely associated with the percentage decline in stimulated C-peptide from 0 to 12 months (nominally p < 0.05). We conclude that associations between different immune mediators are strikingly but not exclusively tied in autoimmune diabetes. BMI is a major confounder in the analysis of associations to autoimmunity. Associations of beta cell decline to individual immune mediators need confirmation in further studies. Topics: Adolescent; Adult; Age of Onset; Autoimmunity; Body Mass Index; C-Peptide; Chemokine CCL3; Cytokines; Diabetes Mellitus, Type 1; Female; Fibroblast Growth Factor 2; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Intercellular Signaling Peptides and Proteins; Male; Statistics, Nonparametric; Young Adult | 2014 |
Defective glucagon secretion during hypoglycemia after intrahepatic but not nonhepatic islet autotransplantation.
Defective glucagon secretion during hypoglycemia after islet transplantation has been reported in animals and humans with type 1 diabetes. To ascertain whether this is true of islets from nondiabetic humans, subjects with autoislet transplantation in the intrahepatic site only (TP/IAT-H) or in intrahepatic plus nonhepatic (TP/IAT-H+NH) sites were studied. Glucagon responses were examined during stepped hypoglycemic clamps. Glucagon and symptom responses during hypoglycemia were virtually absent in subjects who received islets in the hepatic site only (glucagon increment over baseline = 1 ± 6, pg/mL, mean ± SE, n = 9, p = ns; symptom score = 1 ± 1, p = ns). When islets were transplanted in both intrahepatic + nonhepatic sites, glucagon and symptom responses were not significantly different than Control Subjects (TP/IAT-H + NH: glucagon increment = 54 ± 14, n = 5; symptom score = 7 ± 3; control glucagon increment = 67 ± 15, n = 5; symptom score = 8 ± 1). In contrast, glucagon responses to intravenous arginine were present in TP/IAT-H recipients (TP/IAT: glucagon response = 37 ± 8, n = 7). Transplantation of a portion of the islets into a nonhepatic site should be seriously considered in TP/IAT to avoid posttransplant abnormalities in glucagon and symptom responses to hypoglycemia. Topics: Adult; Arginine; Autografts; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Hypoglycemia; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Male; Pancreatectomy; Pancreatic Diseases; Pancreatic Ducts; Pancreatitis; Treatment Outcome | 2014 |
Composition and function of macroencapsulated human embryonic stem cell-derived implants: comparison with clinical human islet cell grafts.
β-Cells generated from large-scale sources can overcome current shortages in clinical islet cell grafts provided that they adequately respond to metabolic variations. Pancreatic (non)endocrine cells can develop from human embryonic stem (huES) cells following in vitro derivation to pancreatic endoderm (PE) that is subsequently implanted in immune-incompetent mice for further differentiation. Encapsulation of PE increases the proportion of endocrine cells in subcutaneous implants, with enrichment in β-cells when they are placed in TheraCyte-macrodevices and predominantly α-cells when they are alginate-microencapsulated. At posttransplant (PT) weeks 20-30, macroencapsulated huES implants presented higher glucose-responsive plasma C-peptide levels and a lower proinsulin-over-C-peptide ratio than human islet cell implants under the kidney capsule. Their ex vivo analysis showed the presence of single-hormone-positive α- and β-cells that exhibited rapid secretory responses to increasing and decreasing glucose concentrations, similar to isolated human islet cells. However, their insulin secretory amplitude was lower, which was attributed in part to a lower cellular hormone content; it was associated with a lower glucose-induced insulin biosynthesis, but not with lower glucagon-induced stimulation, which together is compatible with an immature functional state of the huES-derived β-cells at PT weeks 20-30. These data support the therapeutic potential of macroencapsulated huES implants but indicate the need for further functional analysis. Their comparison with clinical-grade human islet cell grafts sets references for future development and clinical translation. Topics: Animals; C-Peptide; Cell Differentiation; Cell Line; Cells, Immobilized; Crosses, Genetic; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Glucagon-Secreting Cells; Humans; Implants, Experimental; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Kidney; Membranes; Mice, Inbred NOD; Mice, SCID; Proinsulin; Subcutaneous Tissue; Tissue Scaffolds; Transplantation, Heterologous; Transplantation, Heterotopic | 2014 |
Partial remission definition: validation based on the insulin dose-adjusted HbA1c (IDAA1C) in 129 Danish children with new-onset type 1 diabetes.
To validate the partial remission (PR) definition based on insulin dose-adjusted HbA1c (IDAA1c).. The IDAA1c was developed using data in 251 children from the European Hvidoere cohort. For validation, 129 children from a Danish cohort were followed from the onset of type 1 diabetes (T1D). Receiver operating characteristic curve (ROC) analysis was used to evaluate the predictive value of IDAA1c and age on partial C-peptide remission (stimulated C-peptide, SCP > 300 pmol/L).. PR (IDAA1c ≤ 9) in the Danish and Hvidoere cohorts occurred in 62 vs. 61% (3 months, p = 0.80), 47 vs. 44% (6 months, p = 0.57), 26 vs. 32% (9 months, p = 0.32) and 19 vs. 18% (12 months, p = 0.69). The effect of age on SCP was significantly higher in the Danish cohort compared with the Hvidoere cohort (p < 0.0001), likely due to higher attained Boost SCP, so the sensitivity and specificity of those in PR by IDAA1c ≤ 9, SCP > 300 pmol/L was 0.85 and 0.62 at 6 months and 0.62 vs. 0.38 at 12 months, respectively. IDAA1c with age significantly improved the ROC analyses and the AUC reached 0.89 ± 0.04 (age) vs. 0.94 ± 0.02 (age + IDAA1c) at 6 months (p < 0.0004) and 0.76 ± 0.04 (age) vs. 0.90 ± 0.03 (age + IDAA1c) at 12 months (p < 0.0001).. The diagnostic and prognostic power of the IDAA1c measure is kept but due to the higher Boost stimulation in the Danish cohort, the specificity of the formula is lower with the chosen limits for SCP (300 pmol/L) and IDAA1c ≤9, respectively. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Cohort Studies; Denmark; Diabetes Mellitus, Type 1; Diagnosis, Differential; Female; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Infant; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Male; Prediabetic State; Remission Induction; Sensitivity and Specificity | 2014 |
Fasting and postprandial liver glycogen content in patients with type 1 diabetes mellitus after successful pancreas-kidney transplantation with systemic venous insulin delivery.
In patients with type 1 diabetes mellitus (T1DM), insulin is usually replaced systemically (subcutaneously) and not via the physiological portal route. According to previous studies, the liver's capacity to store glycogen is reduced in T1DM patients, but it remains unclear whether this is due to hyperglycaemia, or whether the route of insulin supply could contribute to this phenomenon. T1DM patients after successful pancreas-kidney transplantation with systemic venous drainage (T1DM-PKT) represent a suitable human model to further investigate this question, because they are normoglycaemic, but their liver receives insulin from the pancreas transplant via the systemic route.. In nine T1DM-PKT, nine controls without diabetes (CON) and seven patients with T1DM (T1DM), liver glycogen content was measured at fasting and after two standardized meals employing (13) C-nuclear-magnetic-resonance-spectroscopy. Circulating glucose and glucoregulatory hormones were measured repeatedly throughout the study day.. The mean and fasting concentrations of peripheral plasma glucose, insulin, glucagon and C-peptide were comparable between T1DM-PKT and CON, whereas T1DM were hyperglycaemic and hyperinsulinaemic (P < 0·05 vs T1DM-PKT and CON). Total liver glycogen content at fasting and after breakfast did not differ in the three groups. After lunch, T1DM-PKT and T1DM had a 14% and 21% lower total liver glycogen content than CON (P < 0·02).. In spite of normalized glycaemic control, postprandial liver glycogen content was reduced in T1DM-PKT with systemic venous drainage. Thus, not even optimized systemic insulin substitution is able to resolve the defect in postprandial liver glycogen storage seen in T1DM patients. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Humans; Insulin; Kidney Transplantation; Liver Glycogen; Male; Middle Aged; Pancreas Transplantation; Postprandial Period; Radioimmunoassay | 2014 |
Residual C-peptide in patients with Type 1 diabetes and multiethnic backgrounds.
To evaluate serum C-peptide in 88 patients from a multiethnic population with Type-1 diabetes and variable disease durations.. Eighty-eight patients with a mean disease duration of 8.1 +7.6 years were included and underwent C-peptide measurement before and after glucagon stimulation. Chi-squared and Mann Whitney U-tests were used to compare the variables between groups (all two-tailed, α = 0.05). Spearmans correlation coefficient was used to test the association between the continuous variables. Logistic regression was used for the multivariate analysis. Twenty-eight (31.8%) individuals had significantly detectable C-peptide levels after stimuli, particularly those with a shorter disease duration (p<0.001).. Patients with detectable C-peptide levels required lower insulin doses (p<0.009) and had similar HbA1C results (p = 0.182) and fewer chronic complications (p = 0.029).. C-peptide detection was common in Type-1 diabetics, particularly shortly after being diagnosed. This result may have clinical implications. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Epidemiologic Methods; Female; Glucagon; Humans; Luminescence; Male; Sex Factors; Time Factors; Young Adult | 2013 |
Effect of calcitriol on bone turnover and osteocalcin in recent-onset type 1 diabetes.
Vitamin D supplementation in childhood improves the achievement of peak bone mass. We investigated the effect of supplementation with calcitriol on bone turnover in recent-onset type 1 diabetes (T1D). Moreover, the association between osteocalcin and parameters of β-cell function and metabolic control was examined.. We conducted a post-hoc analysis of a double-blind, placebo-controlled study of calcitriol supplementation to preserve β-cell function. 27 recent-onset T1D subjects, mean age 22 years, were randomized to 0.25 µg calcitriol per day or placebo (1:1) and followed up for one year. Changes in bone formation (osteoclacin) and resorption (beta-CrossLaps) markers, and differences between placebo and calcitriol-treated group were evaluated. At baseline, osteocalcin levels were significantly lower in female than in male patients (P<0.01) while no other metabolic parameters as HbA1c and C-peptide differed between gender. No significant correlations were found in relation to HbA1c, insulin requirement and C-peptide. At 1 year follow-up, no significant differences were observed between calcitriol and placebo groups for osteocalcin and β-CrossLaps. In the placebo group osteocalcin levels were unrelated with parameters of metabolic control, such as C-peptide, insulin requirement or HbA1c. Changes of C-peptide, insulin requirement and HbA1c were not related to osteocalcin levels.. Supplementation with 0.25 µg calcitriol per day to patients with new-onset T1D does not affect circulating markers of bone turnover. OC levels were unrelated to β-cell function and other metabolic parameters suggesting that OC is ineffective to control pancreatic function in presence of aggressive autoimmune destruction. Topics: Adolescent; Adult; Age of Onset; Bone Resorption; C-Peptide; Calcitriol; Child; Collagen; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin-Secreting Cells; Male; Osteocalcin; Osteogenesis; Peptide Fragments; Vitamin D | 2013 |
Diurnal pattern of insulin action in type 1 diabetes: implications for a closed-loop system.
We recently demonstrated a diurnal pattern to insulin action (i.e., insulin sensitivity [SI]) in healthy individuals with higher SI at breakfast than at dinner. To determine whether such a pattern exists in type 1 diabetes, we studied 19 subjects with C-peptide-negative diabetes (HbA1c 7.1 ± 0.6%) on insulin pump therapy with normal gastric emptying. Identical mixed meals were ingested during breakfast, lunch, and dinner at 0700, 1300, and 1900 h in randomized Latin square of order on 3 consecutive days when measured daily physical activity was equal. The triple tracer technique enabled measurement of glucose fluxes. Insulin was administered according to the customary insulin:carbohydrate ratio for each participant. Although postprandial glucose excursions did not differ among meals, insulin concentration was higher (P < 0.01) and endogenous glucose production less suppressed (P < 0.049) at breakfast than at lunch. There were no differences in meal glucose appearance or in glucose disappearance between meals. Although there was no statistical difference (P = 0.34) in SI between meals in type 1 diabetic subjects, the diurnal pattern of SI taken across the three meals in its entirety differed (P = 0.016) from that of healthy subjects. Although the pattern in healthy subjects showed decreasing SI between breakfast and lunch, the reverse SI pattern was observed in type 1 diabetic subjects. The results suggest that in contrast to healthy subjects, SI diurnal pattern in type 1 diabetes is specific to the individual and cannot be extrapolated to the type 1 diabetic population as a whole, implying that artificial pancreas algorithms may need to be personalized. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Aspart; Male; Middle Aged; Motor Activity; Postprandial Period | 2013 |
Types of pediatric diabetes mellitus defined by anti-islet autoimmunity and random C-peptide at diagnosis.
To test the hypothesis that anti-islet autoantibody expression and random serum C-peptide obtained at diagnosis define phenotypes of pediatric diabetes with distinct clinical features.. We analyzed 607 children aged <19 yr consecutively diagnosed with diabetes after exclusion of 13% of cases with secondary diabetes (e.g., cystic fibrosis related, steroid induced) and 7.3% of cases lacking measurement of C-peptide and/or autoantibodies.. Autoantibody positivity (A+) was defined as ≥ 1 positive out of GAD65, insulin, and ICA512 antibodies. Preserved beta-cell function (β+) was defined as random serum C-peptide at diagnosis ≥ 0.6 ng/mL. Body mass index (BMI) was measured at median 1.2 months after diagnosis. Characteristics at diagnosis and 2 yr (range 18-30 months) after diagnosis were compared among groups.. Autoantibody expression and C-peptide at diagnosis defined the following groups: A+β- (52.1% of the children), A+β+ (32.8%), A-β+ (12.5%), and A-β- (2.6%). These four groups differed in gender, race/ethnicity, and clinical characteristics at diagnosis [i.e., age, pubertal development, obesity/overweight, diabetic ketoacidosis, glycemia, and hemoglobin A1c (HbA1c)] and at 2 yr (i.e., clinical diagnosis, treatment, and HbA1c) (all p < 0.0001). Among all β+ children, C-peptide >2 ng/mL was associated with lower HbA1c at onset (p = 0.0001) and, in the A+β+ subgroup, with higher frequency of achieving HbA1c < 7% at 2 yr (p = 0.03). All three patients (0.7% of total) with monogenic diabetes (maturity onset diabetes of the young, MODY) were A-β+ with C-peptide between 0.6 and 2 ng/mL.. Anti-islet autoantibodies status and serum random C-peptide at diagnosis define four distinct phenotypes of pediatric diabetes with prognostic value. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Phenotype; Receptor-Like Protein Tyrosine Phosphatases, Class 8 | 2013 |
Latent autoimmune diabetes in adults is perched between type 1 and type 2: evidence from adults in one region of Spain.
The aim of this study was to characterize the clinical characteristics and insulin secretion in adults with latent autoimmune diabetes in adults (LADA). We also compared these characteristics in subjects with antibody-negative type 2 diabetes (T2DM) or adult-onset type 1 diabetes (T1DM) to subjects with LADA.. In this cross-sectional study, 82 patients with LADA, 78 with T1DM and 485 with T2DM were studied. Clinical and metabolic data, in particular those that related to metabolic syndrome, fasting C-peptide and islet-cell autoantibodies [glutamic acid decarboxylase (GADAb) and IA2 (IA2Ab)] were measured.. The frequency of metabolic syndrome in patients with LADA (37.3%) was higher than in those with T1DM (15.5%; p = 0.005) and lower than in patients with T2DM (67.2%; p < 0.001). During the first 36 months of the disease, the C-peptide concentration in LADA patients was higher than in subjects with T1DM but was lower than in T2DM patients (p < 0.01 for comparisons). Glycemic control in LADA patients (HbA1c 8.1%) was worse than in patients with T2DM (HbA1c 7.6%; p =0.007). An inverse association between GADAb titers and C-peptide concentrations was found in subjects with LADA (p < 0.001). Finally, LADA patients rapidly progressed to insulin treatment.. As in other European populations, patients with LADA in Spain have a distinct metabolic profile compared with patients with T1DM or T2DM. LADA is also associated with higher impairment of beta-cell function and has worse glycemic control than in T2DM. Beta cell function is related to GADAb titers in patients with LADA. Topics: Adult; Aged; Autoantibodies; Autoimmunity; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Insulin Secretion; Male; Metabolic Syndrome; Middle Aged; Spain | 2013 |
Fasting and meal-stimulated residual beta cell function is positively associated with serum concentrations of proinflammatory cytokines and negatively associated with anti-inflammatory and regulatory cytokines in patients with longer term type 1 diabetes.
Cytokines may promote or inhibit disease progression in type 1 diabetes. We investigated whether systemic proinflammatory, anti-inflammatory and regulatory cytokines associated differently with fasting and meal-stimulated beta cell function in patients with longer term type 1 diabetes.. The beta cell function of 118 patients with type 1 diabetes of duration of 0.75-4.97 years was tested using a standardised liquid mixed meal test (MMT). Serum samples obtained at -5 to 120 min were analysed by multiplex bead-based technology for proinflammatory (IL-6, TNF-α), anti-inflammatory (IL-1 receptor antagonist [IL-1RA]) and regulatory (IL-10, TGF-β1-3) cytokines, and by standard procedures for C-peptide. Differences in beta cell function between patient groups were assessed using stepwise multiple regression analysis adjusting for sex, age, duration of diabetes, BMI, HbA1c and fasting blood glucose.. High fasting systemic concentrations of the proinflammatory cytokines IL-6 and TNF-α were associated with increased fasting and stimulated C-peptide concentrations even after adjustment for confounders (p < 0.03). Interestingly, increased concentrations of anti-inflammatory/regulatory IL-1RA, IL-10, TGF-β1 and TGF-β2 were associated with lower fasting and stimulated C-peptide levels (p < 0.04), losing significance on adjustment for anthropometric variables. During the MMT, circulating concentrations of IL-6 and TNF-α increased (p < 0.001) while those of IL-10 and TGF-β1 decreased (p < 0.02) and IL-1RA and TGF-β2 remained unchanged.. The association between better preserved beta cell function in longer term type 1 diabetes and increased systemic proinflammatory cytokines and decreased anti-inflammatory and regulatory cytokines is suggestive of ongoing inflammatory disease activity that might be perpetuated by the remaining beta cells. These findings should be considered when designing immune intervention studies aimed at patients with longer term type 1 diabetes and residual beta cell function. Topics: Adolescent; Adult; Blood Glucose; Body Mass Index; C-Peptide; Child; Cytokines; Diabetes Mellitus, Type 1; Diet; Fasting; Female; Gene Expression Regulation; Humans; Inflammation; Insulin-Secreting Cells; Male; Time Factors; Young Adult | 2013 |
Decline of C-peptide during the first year after diagnosis of Type 1 diabetes in children and adolescents.
We studied the decline of C-peptide during the first year after diagnosis of Type 1 diabetes (T1D), and its relation to various factors.. 3824/4017 newly diagnosed patients (95%) were classified as T1D in a national study. In a non-selected subgroup of 1669 T1D patients we determined non-fasting C-peptide both at diagnosis and after 1 year, and analyzed decline in relation to clinical symptoms and signs, initial C-peptide and occurrence of auto-antibodies.. Younger children lost more C-peptide (p<0.001) and the higher the C-peptide at diagnosis the larger the decline during the first year (p<0.0000). Patients with higher BMI had higher C-peptide at diagnosis but lost more (p<0.01), and those with lower HbA1c, without symptoms and signs at diagnosis, and with higher BMI, had higher C-peptide at diagnosis, but lost more during the first year (p<0.001). Finally, patients diagnosed during autumn had higher C-peptide at diagnosis, but lost more during the coming year (p<0.001). Occurrence of auto-antibodies did not correlate with C-peptide decline, except possibly for a more rapid loss in IAA-positive patients.. Even in a restricted geographical area and narrow age range (<18 years), the natural course of Type 1 diabetes is heterogeneous. This should be considered in clinical trials. Topics: Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans | 2013 |
CD4⁺ CD45RA⁻ FoxP3high activated regulatory T cells are functionally impaired and related to residual insulin-secreting capacity in patients with type 1 diabetes.
Accumulating lines of evidence have suggested that regulatory T cells (T(regs)) play a central role in T cell-mediated immune response and the development of type 1A and fulminant type 1 diabetes. CD4(+) forkhead box protein 3 (FoxP3)(+) T cells are composed of three phenotypically and functionally distinct subpopulations; CD45RA(+) FoxP3(low) resting T(regs) (r-T(regs)), CD45RA(-) FoxP3(high) activated T(regs) (a-T(regs)) and CD45RA(-) FoxP3(low) non-suppressive T cells (non-T(regs)). We aimed to clarify the frequency of these three subpopulations in CD4(+) FoxP3(+) T cells and the function of a-T(regs) with reference to subtypes of type 1 diabetes. We examined 20 patients with type 1A diabetes, 15 patients with fulminant type 1 diabetes, 20 patients with type 2 diabetes and 30 healthy control subjects. A flow cytometric analysis in the peripheral blood was performed for the frequency analysis. The suppressive function of a-T(regs) was assessed by their ability to suppress the proliferation of responder cells in a 1/2:1 co-culture. A flow cytometric analysis in the peripheral blood demonstrated that the frequency of a-T(regs) was significantly higher in type 1A diabetes, but not in fulminant type 1 diabetes, than the controls. Further, the proportion of a-T(regs) among CD4(+) FoxP3(+) T cells was significantly higher in patients with type 1A diabetes with detectable C-peptide but not in patients with type 1A diabetes without it and with fulminant type 1 diabetes. A proliferation suppression assay showed that a-T(regs) were functionally impaired both in fulminant type 1 diabetes and in type 1A diabetes. In conclusion, a-T(regs) were functionally impaired, related to residual insulin-secreting capacity and may be associated with the development of type 1 diabetes. Topics: C-Peptide; CD4 Antigens; Cell Proliferation; Cell Separation; Cells, Cultured; Coculture Techniques; Diabetes Mellitus, Type 1; Flow Cytometry; Forkhead Transcription Factors; Humans; Insulin; Insulin Secretion; Leukocyte Common Antigens; Lymphocyte Activation; T-Lymphocyte Subsets; T-Lymphocytes, Regulatory | 2013 |
Improvement in β-cell secretory capacity after human islet transplantation according to the CIT07 protocol.
The Clinical Islet Transplantation 07 (CIT07) protocol uses antithymocyte globulin and etanercept induction, islet culture, heparinization, and intensive insulin therapy with the same low-dose tacrolimus and sirolimus maintenance immunosuppression as in the Edmonton protocol. To determine whether CIT07 improves engrafted islet β-cell mass, our center measured β-cell secretory capacity from glucose-potentiated arginine tests at days 75 and 365 after transplantation and compared those results with the results previously achieved by our group using the Edmonton protocol and normal subjects. All subjects were insulin free, with CIT07 subjects receiving fewer islet equivalents from a median of one donor compared with two donors for Edmonton protocol subjects. The acute insulin response to glucose-potentiated arginine (AIRpot) was greater in the CIT07 protocol than in the Edmonton protocol and was less in both cohorts than in normal subjects, with similar findings for C-peptide. The CIT07 subjects who completed reassessment at day 365 exhibited increasing AIRpot by trend relative to that of day 75. These data indicate that engrafted islet β-cell mass is markedly improved with the CIT07 protocol, especially given more frequent use of single islet donors. Although several peritransplant differences may have each contributed to this improvement, the lack of deterioration in β-cell secretory capacity over time in the CIT07 protocol suggests that low-dose tacrolimus and sirolimus are not toxic to islets. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Sirolimus; Tacrolimus; Treatment Outcome | 2013 |
Low C-peptide levels and decreased expression of TNF and CD45 in children with high risk of type 1 diabetes.
Type 1 diabetes (T1D) patients have numeral and functional defects in peripheral immune cells, but the pre-diabetic period is fairly uncharacterized. Our aim was to analyze expression of immunological markers in T1D high risk children and relate it to clinical/immunological parameters. Children from ABIS (All Babies in Southeast Sweden) with ≥2 diabetes related autoantibodies were considered at high risk. Age-matched controls and new-onset T1D patients were included. Expression of genes related to immune cell function and different arms of the immune system was assessed in peripheral blood mononuclear cells using PCR array. Risk children had lower TNF and CD45, and although there were few differences between the groups, expression of many genes differed when comparing children with regard to residual insulin secretion. Hence, expression of immune related genes seemed related not only to the autoimmune process but rather to residual β-cell function, which was decreased already during the pre-diabetic phase. Topics: Adolescent; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Gene Expression Profiling; HLA Antigens; Humans; Leukocyte Common Antigens; Leukocytes, Mononuclear; Male; Peptide Fragments; Prediabetic State; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sweden; Tumor Necrosis Factor-alpha | 2013 |
The influence of exposure to maternal diabetes in utero on the rate of decline in β-cell function among youth with diabetes.
Abstract We explored the influence of exposure to maternal diabetes in utero on β cell decline measured by fasting C-peptide (FCP) among 1079 youth <20 years with diabetes, including 941 with type 1 and 138 with type 2 diabetes. Youths exposed to maternal diabetes had FCP levels that were 17% lower among youth with type 2 diabetes [95% confidence interval (CI): -34%, +6%] and 15% higher among youth with type 1 diabetes (95%CI: -14%, +55%) than their unexposed counterparts, although differences were not statistically significant (p=0.13 and p=0.35, respectively). Exposure to maternal diabetes was not associated with FCP decline in youth with type 2 (p=0.16) or type 1 diabetes (p=0.90); nor was the effect of in utero exposure on FCP modified by diabetes type. Findings suggest that exposure to maternal diabetes in utero may not be an important determinant of short-term β-cell function decline in youth with type 1 or type 2 diabetes. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Humans; Insulin-Secreting Cells; Male; Pregnancy | 2013 |
Reversal of hyperglycemia by insulin-secreting rat bone marrow- and blastocyst-derived hypoblast stem cell-like cells.
β-cell replacement may efficiently cure type 1 diabetic (T1D) patients whose insulin-secreting β-cells have been selectively destroyed by autoantigen-reactive T cells. To generate insulin-secreting cells we used two cell sources: rat multipotent adult progenitor cells (rMAPC) and the highly similar rat extra-embryonic endoderm precursor (rXEN-P) cells isolated under rMAPC conditions from blastocysts (rHypoSC). rMAPC/rHypoSC were sequentially committed to definitive endoderm, pancreatic endoderm, and β-cell like cells. On day 21, 20% of rMAPC/rHypoSC progeny expressed Pdx1 and C-peptide. rMAPCr/HypoSC progeny secreted C-peptide under the stimulus of insulin agonist carbachol, and was inhibited by the L-type voltage-dependent calcium channel blocker nifedipine. When rMAPC or rHypoSC differentiated d21 progeny were grafted under the kidney capsule of streptozotocin-induced diabetic nude mice, hyperglycemia reversed after 4 weeks in 6/10 rMAPC- and 5/10 rHypoSC-transplanted mice. Hyperglycemia recurred within 24 hours of graft removal and the histological analysis of the retrieved grafts revealed presence of Pdx1-, Nkx6.1- and C-peptide-positive cells. The ability of both rMAPC and HypoSC to differentiate to functional β-cell like cells may serve to gain insight into signals that govern β-cell differentiation and aid in developing culture systems to commit other (pluripotent) stem cells to clinically useful β-cells for cell therapy of T1D. Topics: Animals; Blastocyst; Blotting, Western; Bone Marrow Cells; C-Peptide; Cell Differentiation; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Endoderm; Gene Expression; Germ Layers; Homeodomain Proteins; Humans; Hyperglycemia; Insulin-Secreting Cells; Mice; Mice, Inbred BALB C; Mice, Nude; Multipotent Stem Cells; Rats; Rats, Inbred F344; Reverse Transcriptase Polymerase Chain Reaction; Stem Cell Transplantation; Time Factors; Trans-Activators | 2013 |
Genetically engineered human islets protected from CD8-mediated autoimmune destruction in vivo.
Islet transplantation is a promising therapy for type 1 diabetes, but graft function and survival are compromised by recurrent islet autoimmunity. Immunoprotection of islets will be required to improve clinical outcome. We engineered human β cells to express herpesvirus-encoded immune-evasion proteins, "immunevasins." The capacity of immunevasins to protect β cells from autoreactive T-cell killing was evaluated in vitro and in vivo in humanized mice. Lentiviral vectors were used for efficient genetic modification of primary human β cells without impairing their function. Using a novel β-cell-specific reporter gene assay, we show that autoreactive cytotoxic CD8(+) T-cell clones isolated from patients with recent onset diabetes selectively destroyed human β cells, and that coexpression of the human cytomegalovirus-encoded US2 protein and serine proteinase inhibitor 9 offers highly efficient protection in vitro. Moreover, coimplantation of these genetically modified pseudoislets with β-cell-specific cytotoxic T cells into immunodeficient mice achieves preserved human insulin production and C-peptide secretion. Collectively, our data provide proof of concept that human β cells can be efficiently genetically modified to provide protection from killing mediated by autoreactive T cells and retain their function in vitro and in vivo. Topics: Animals; Autoimmunity; C-Peptide; CD8-Positive T-Lymphocytes; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; Gene Expression; Gene Order; Genetic Vectors; HLA-A2 Antigen; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Islets of Langerhans Transplantation; Lentivirus; Male; Mice; Organ Specificity; Promoter Regions, Genetic; Protein Precursors; Serpins; T-Lymphocytes, Cytotoxic; Transduction, Genetic; Viral Envelope Proteins | 2013 |
Comment on: Greenbaum et al. Fall in C-peptide during first 2 years from diagnosis: evidence of at least two distinct phases from composite type 1 Diabetes TrialNet data. Diabetes 2012;61:2066-2073.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans | 2013 |
Response to Comment on: Greenbaum et al. Fall in C-peptide during first 2 years from diagnosis: evidence of at least two distinct phases from composite type 1 diabetes TrialNet data. Diabetes 2012;61:2066-2073.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans | 2013 |
Autologous pancreatic islet transplantation in human bone marrow.
The liver is the current site of choice for pancreatic islet transplantation, even though it is far from being ideal. We recently have shown in mice that the bone marrow (BM) may be a valid alternative to the liver, and here we report a pilot study to test feasibility and safety of BM as a site for islet transplantation in humans. Four patients who developed diabetes after total pancreatectomy were candidates for the autologous transplantation of pancreatic islet. Because the patients had contraindications for intraportal infusion, islets were infused in the BM. In all recipients, islets engrafted successfully as shown by measurable posttransplantation C-peptide levels and histopathological evidence of insulin-producing cells or molecular markers of endocrine tissue in BM biopsy samples analyzed during follow-up. Thus far, we have recorded no adverse events related to the infusion procedure or the presence of islets in the BM. Islet function was sustained for the maximum follow-up of 944 days. The encouraging results of this pilot study provide new perspectives in identifying alternative sites for islet infusion in patients with type 1 diabetes. Moreover, this is the first unequivocal example of successful engraftment of endocrine tissue in the BM in humans. Topics: Aged; Blood Glucose; Bone Marrow; C-Peptide; Diabetes Mellitus, Type 1; Feasibility Studies; Female; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Magnetic Resonance Imaging; Male; Middle Aged; Pancreatectomy; Pilot Projects; Transplantation, Autologous; Treatment Outcome | 2013 |
The use of intermediate endpoints in the design of type 1 diabetes prevention trials.
This paper presents a rationale for the selection of intermediate endpoints to be used in the design of type 1 diabetes prevention clinical trials.. Relatives of individuals diagnosed with type 1 diabetes were enrolled on the TrialNet Natural History Study and screened for diabetes-related autoantibodies. Those with two or more such autoantibodies were analysed with respect to increased HbA1c, decreased C-peptide following an OGTT, or abnormal OGTT values as intermediate markers of disease progression.. Over 2 years, a 10% increase in HbA1c, and a 20% or 30% decrease in C-peptide from baseline, or progression to abnormal OGTT, occurred with a frequency between 20% and 41%. The 3- to 5-year risk of type 1 diabetes following each intermediate endpoint was high, namely 47% to 84%. The lower the incidence of the endpoint being reached, the higher the risk of diabetes. A diabetes prevention trial using these intermediate endpoints would require a 30% to 50% smaller sample size than one using type 1 diabetes as the endpoint.. The use of an intermediate endpoint in diabetes prevention is based on the generally held view of disease progression from initial occurrence of autoantibodies through successive immunological and metabolic changes to manifest type 1 diabetes. Thus, these markers are suitable for randomised phase 2 trials, which can more rapidly screen promising new therapies, allowing them to be subsequently confirmed in definitive phase 3 trials. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Infant; Male; Middle Aged; Young Adult | 2013 |
Complex multi-block analysis identifies new immunologic and genetic disease progression patterns associated with the residual β-cell function 1 year after diagnosis of type 1 diabetes.
The purpose of the present study is to explore the progression of type 1 diabetes (T1D) in Danish children 12 months after diagnosis using Latent Factor Modelling. We include three data blocks of dynamic paraclinical biomarkers, baseline clinical characteristics and genetic profiles of diabetes related SNPs in the analyses. This method identified a model explaining 21.6% of the total variation in the data set. The model consists of two components: (1) A pattern of declining residual β-cell function positively associated with young age, presence of diabetic ketoacidosis and long duration of disease symptoms (P = 0.0004), and with risk alleles of WFS1, CDKN2A/2B and RNLS (P = 0.006). (2) A second pattern of high ZnT8 autoantibody levels and low postprandial glucagon levels associated with risk alleles of IFIH1, TCF2, TAF5L, IL2RA and PTPN2 and protective alleles of ERBB3 gene (P = 0.0005). These results demonstrate that Latent Factor Modelling can identify associating patterns in clinical prospective data--future functional studies will be needed to clarify the relevance of these patterns. Topics: Adolescent; Age of Onset; Alleles; Autoantibodies; C-Peptide; Cation Transport Proteins; Child; Diabetes Mellitus, Type 1; Disease Progression; Female; Genetic Predisposition to Disease; Glycated Hemoglobin; Humans; Insulin-Secreting Cells; Male; Models, Biological; Polymorphism, Single Nucleotide; Prospective Studies; Risk; Zinc Transporter 8 | 2013 |
Nutritional factors and preservation of C-peptide in youth with recently diagnosed type 1 diabetes: SEARCH Nutrition Ancillary Study.
To test the novel hypothesis that nutritional factors previously associated with type 1 diabetes etiology or with insulin secretion are prospectively associated with fasting C-peptide (FCP) concentration among youth recently diagnosed with type 1 diabetes.. Included were 1,316 youth with autoantibody-positive type 1 diabetes who participated in the SEARCH for Diabetes in Youth study (baseline disease duration, 9.9 months; SD, 6.3). Nutritional exposures included breastfeeding and age at introduction of complementary foods, baseline plasma long-chain omega-3 fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), vitamin D, vitamin E, and, from a baseline food frequency questionnaire, estimated intake of the branched-chain amino acid leucine and total carbohydrate. Multiple linear regression models were conducted to relate each nutritional factor to baseline FCP adjusted for demographics, disease-related factors, and other confounders. Prospective analyses included the subset of participants with preserved β-cell function at baseline (baseline FCP ≥0.23 ng/mL) with additional adjustment for baseline FCP and time (mean follow-up, 24.3 months; SD, 8.2; n = 656). FCP concentration was analyzed as log(FCP).. In adjusted prospective analyses, baseline EPA (P = 0.02), EPA plus DHA (P = 0.03), and leucine (P = 0.03) were each associated positively and significantly with FCP at follow-up. Vitamin D was unexpectedly inversely associated with FCP (P = 0.002).. Increased intake of branched-chain amino acids and long-chain omega-3 fatty acids may support preservation of β-cell function. This represents a new direction for research to improve prognosis for type 1 diabetes. Topics: Adolescent; Amino Acids, Branched-Chain; C-Peptide; Child; Diabetes Mellitus, Type 1; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fasting; Fatty Acids, Omega-3; Female; Humans; Male; Nutritional Status; Prospective Studies; United States | 2013 |
Immunotherapy: Modified proinsulin to treat T1DM.
Topics: C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Female; Humans; Male; Plasmids; Proinsulin | 2013 |
North American Ginseng (Panax quinquefolius) prevents hyperglycemia and associated pancreatic abnormalities in diabetes.
North American ginseng (NAG) has received increasing attention as an alternative medicine for the treatment of diabetes. Extract of the NAG root has been reported to possess antidiabetic properties, but the underlying mechanisms for such effects have not been identified. Here we investigated the effects of NAG root extract on type 1 and 2 diabetes and the underlying mechanisms involved for such effects. Type 1 [C57BL/6 mice with streptozotocin (STZ)-induction] and type 2 (db/db) diabetic models were examined. Groups of diabetic mice (both type 1 and 2) were treated with alcoholic extract of the NAG root (200 mg/kg BW/day, oral gavage) for 1 or 2 months following onset of diabetes. Ginseng treatment significantly increased the body weight in type 1 diabetic animals in contrast to the type 2 model, where it caused diminution of body weight. Blood glucose and glycated hemoglobin levels diminished in the diabetic groups of both models with NAG treatment. Interestingly, plasma insulin and C-peptide levels were significantly increased in the STZ-diabetic mice, whereas they were reduced in the db/db mice following NAG treatment. Histological and morphometric analyses (islet/pancreas ratio) of the pancreas revealed an increase in the islet area following the treatment compared to both the untreated diabetic groups. These data indicate that NAG possibly causes regeneration of β-cells resulting in enhanced insulin secretion. On the other hand, in type 2 diabetes, the additional effects of NAG on body weight might have also resulted in improved glucose control. Topics: Animals; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Male; Mice; Mice, Inbred C57BL; Panax; Pancreas; Phytotherapy; Plant Extracts | 2013 |
Metabolic assessment prior to total pancreatectomy and islet autotransplant: utility, limitations and potential.
Islet autotransplant (IAT) may ameliorate postsurgical diabetes following total pancreatectomy (TP), but outcomes are dependent upon islet mass, which is unknown prior to pancreatectomy. We evaluated whether preoperative metabolic testing could predict islet isolation outcomes and thus improve assessment of TPIAT candidates. We examined the relationship between measures from frequent sample IV glucose tolerance tests (FSIVGTT) and mixed meal tolerance tests (MMTT) and islet mass in 60 adult patients, with multivariate logistic regression modeling to identify predictors of islet mass ≥2500 IEQ/kg. The acute C-peptide response to glucose (ACRglu) and disposition index from FSIVGTT correlated modestly with the islet equivalents per kilogram body weight (IEQ/kg). Fasting and MMTT glucose levels and HbA1c correlated inversely with IEQ/kg (r values -0.33 to -0.40, p ≤ 0.05). In multivariate logistic regression modeling, normal fasting glucose (<100 mg/dL) and stimulated C-peptide on MMTT ≥4 ng/mL were associated with greater odds of receiving an islet mass ≥2500 IEQ/kg (OR 0.93 for fasting glucose, CI 0.87-1.0; OR 7.9 for C-peptide, CI 1.75-35.6). In conclusion, parameters obtained from FSIVGTT correlate modestly with islet isolation outcomes. Stimulated C-peptide ≥4 ng/mL on MMTT conveyed eight times the odds of receiving ≥2500 IEQ/kg, a threshold associated with reasonable metabolic control postoperatively. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Pancreatectomy; Pancreatitis, Chronic; Postoperative Complications; Preoperative Care; Prognosis; Prospective Studies; Risk Factors; Transplantation, Autologous | 2013 |
Residual β-Cell function 3-6 years after onset of type 1 diabetes reduces risk of severe hypoglycemia in children and adolescents.
To determine the prevalence of residual β-cell function (RBF) in children after 3-6 years of type 1 diabetes, and to examine the association between RBF and incidence of severe hypoglycemia, glycemic control, and insulin requirements.. A total of 342 children (173 boys) 4.8-18.9 years of age with type 1 diabetes for 3-6 years were included. RBF was assessed by testing meal-stimulated C-peptide concentrations. Information regarding severe hypoglycemia within the past year, current HbA1c, and daily insulin requirements was retrieved from the medical records and through patient interviews.. Ninety-two children (27%) had RBF >0.04 nmol/L. Patients with RBF <0.04 nmol/L were significantly more likely to have severe hypoglycemia than patients with RBF >0.04 nmol/L (odds ratio, 2.59; 95% CI, 1.10-7.08; P < 0.03). HbA1c was significantly higher in patients with RBF <0.04 nmol/L compared with patients with RBF >0.04 nmol/L (mean, 8.49 ± 0.08% [69.3 ± 0.9 mmol/mol] vs. 7.92 ± 0.13% [63.1 ± 1.4 mmol/mol]; P < 0.01), and insulin requirements were significantly lower in patients with RBF >0.2 nmol/L (mean ± SE: 1.07 ± 0.02 vs. 0.93 ± 0.07 units/kg/day; P < 0.04).. We demonstrated considerable phenotypic diversity in RBF among children after 3-6 years of type 1 diabetes. Children with RBF are at lower risk for severe hypoglycemia, have better diabetes regulation, and have lower insulin requirements compared with children without RBF. There appears to be a lower limit for stimulated RBF of ∼0.04 nmol/L that confers a beneficial effect on hypoglycemia and metabolic control. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Meals; Registries | 2013 |
The clinical measures associated with C-peptide decline in patients with type 1 diabetes over 15 years.
This study was done to characterize the natural course of C-peptide levels in patients with type 1 diabetes and identify distinguishing characters among patients with lower rates of C-peptide decline. A sample of 95 children with type 1 diabetes was analyzed to retrospectively track serum levels of C-peptide, HbA1c, weight, BMI, and diabetic complications for the 15 yr after diagnosis. The clinical characteristics were compared between the patients with low and high C-peptide levels, respectively. The average C-peptide level among all patients was significantly reduced five years after diagnosis (P < 0.001). The incidence of diabetic ketoacidosis was significantly lower among the patients with high levels of C-peptide (P = 0.038). The body weight and BMI standard deviation scores (SDS) 15 yr after diagnosis were significantly higher among the patients with low C-peptide levels (weight SDS, P = 0.012; BMI SDS, P = 0.044). In conclusion, C-peptide level was significantly decreased after 5 yr from diagnosis. Type 1 diabetes patients whose beta-cell functions were preserved might have low incidence of diabetic ketoacidosis. The declines of C-peptide level after diagnosis in type 1 diabetes may be associated with changes of body weight and BMI. Topics: Adolescent; Body Mass Index; Body Weight; C-Peptide; Child; Child, Preschool; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Diabetic Retinopathy; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Incidence; Infant; Male; Peripheral Nervous System Diseases; Retrospective Studies | 2013 |
Endocrine secretory reserve and proinsulin processing in recipients of islet of langerhans versus whole pancreas transplants.
β-Cells have demonstrated altered proinsulin processing after islet transplantation. We compare β-cell metabolic responses and proinsulin processing in pancreas and islet transplant recipients with respect to healthy control subjects.. We studied 15 islet and 32 pancreas transplant recipients. Islet subjects were subdivided into insulin-requiring (IR-ISL, n = 6) and insulin-independent (II-ISL, n = 9) groups. Ten healthy subjects served as control subjects. Subjects were administered an intravenous arginine stimulation test, and insulin, C-peptide, total proinsulin, intact proinsulin, and proinsulin fragment levels were determined from serum samples. Acute insulin response (AIR) and proinsulin processing rates were calculated.. We found that basal insulin and C-peptide levels were higher in the pancreas group than in all other groups. II-ISL patients had basal insulin and C-peptide levels similar to healthy control subjects. The IR-ISL group had significantly lower AIRs than all other groups. Basal processing rates were higher in the pancreas and II-ISL groups than in healthy control subjects and the IR-ISL group. After arginine stimulation, all groups had elevated processing rates, with the exception of the IR-ISL group.. Our data suggest that II-ISL transplant recipients can maintain basal metabolic parameters similar to healthy control subjects at the cost of a higher rate of proinsulin processing. IR-ISL transplant recipients, on the other hand, demonstrate both lower insulin response and lower basal rates of proinsulin processing even after arginine stimulation. Topics: Adult; Blood Glucose; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Pancreas Transplantation; Proinsulin | 2013 |
Minimal functional β-cell mass in intraportal implants that reduces glycemic variability in type 1 diabetic recipients.
Previous work has shown a correlation between β-cell number in cultured islet cell grafts and their ability to induce C-peptide secretion after intraportal implantation in C-peptide-negative type1 diabetic patients. In this cross-sectional study, we examined the minimal functional β-cell mass (FBM) in the implant that induces metabolic improvement.. Glucose clamps assessed FBM in 42 recipients with established implants. C-peptide release during each phase was expressed as percentage of healthy control values. Its relative magnitude during a second hyperglycemic phase was most discriminative and therefore selected as a parameter to be correlated with metabolic effects.. Recipients with functioning β-cell implants exhibited average FBM corresponding to 18% of that in normal control subjects (interquartile range 10-33%). Its relative magnitude negatively correlated with HbA1c levels (r = -0.47), daily insulin dose (r = -0.75), and coefficient of variation of fasting glycemia (CVfg) (r = -0.78, retained in multivariate analysis). A correlation between FBM and CVfg <25% appeared from the receiver operating characteristic curve (0.97 [95% CI 0.93-1.00]). All patients with FBM >37% exhibited CVfg <25% and a >50% reduction of their pretransplant CVfg; this occurred in none with FBM <5%. Implants with FBM >18% reduced CVfg from a median pretransplant value of 46 to <25%.. Glucose clamping assesses the degree of restoration in FBM achieved by islet cell implants. Values >37% of normal control subjects appear needed to reduce glycemic variability in type 1 diabetic recipients. Further studies should examine whether the test can help guide decisions on additional islet cell transplants and on adjusting or stopping immunotherapy. Topics: Adult; Blood Glucose; C-Peptide; Cell Count; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Portal Vein | 2013 |
A new home for pancreatic islet transplants: the bone marrow.
Topics: Blood Glucose; Bone Marrow; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans Transplantation; Male | 2013 |
Attainment of metabolic goals in the integrated UK islet transplant program with locally isolated and transported preparations.
The objective was to determine whether metabolic goals have been achieved with locally isolated and transported preparations over the first 3 years of the UK's nationally funded integrated islet transplant program. Twenty islet recipients with C-peptide negative type 1 diabetes and recurrent severe hypoglycemia consented to the study, including standardized meal tolerance tests. Participants received a total of 35 infusions (seven recipients: single graft; 11 recipients: two grafts: two recipients: three grafts). Graft function was maintained in 80% at [median (interquartile range)] 24 (13.5-36) months postfirst transplant. Severe hypoglycemia was reduced from 20 (7-50) episodes/patient-year pretransplant to 0.3 (0-1.6) episodes/patient-year posttransplant (p < 0.001). Resolution of impaired hypoglycemia awareness was confirmed [pretransplant: Gold score 6 (5-7); 24 (13.5-36) months: 3 (1.5-4.5); p < 0.03]. Target HbA1c of <7.0% was attained/maintained in 70% of recipients [pretransplant: 8.0 (7.0-9.6)%; 24 (13.5-36) months: 6.2 (5.7-8.4)%; p < 0.001], with 60% reduction in insulin dose [pretransplant: 0.51 (0.41-0.62) units/kg; 24 (13.5-36) months: 0.20 (0-0.37) units/kg; p < 0.001]. Metabolic outcomes were comparable 12 months posttransplant in those receiving transported versus only locally isolated islets [12 month stimulated C-peptide: transported 788 (114-1764) pmol/L (n = 9); locally isolated 407 (126-830) pmol/L (n = 11); p = 0.32]. Metabolic goals have been attained within the equitably available, fully integrated UK islet transplant program with both transported and locally isolated preparations. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Graft Survival; Humans; Hypoglycemia; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Prospective Studies; Time Factors; Treatment Outcome; United Kingdom | 2013 |
The compelling case for anti-CD3 in type 1 diabetes.
Topics: Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Male | 2013 |
Depleting T cells in newly diagnosed autoimmune (type 1) diabetes--are we getting anywhere?
Topics: Antibodies, Monoclonal, Humanized; C-Peptide; Diabetes Mellitus, Type 1; Humans | 2013 |
Transplantation of human islets without immunosuppression.
Transplantation of pancreatic islets is emerging as a successful treatment for type-1 diabetes. Its current stringent restriction to patients with critical metabolic lability is justified by the long-term need for immunosuppression and a persistent shortage of donor organs. We developed an oxygenated chamber system composed of immune-isolating alginate and polymembrane covers that allows for survival and function of islets without immunosuppression. A patient with type-1 diabetes received a transplanted chamber and was followed for 10 mo. Persistent graft function in this chamber system was demonstrated, with regulated insulin secretion and preservation of islet morphology and function without any immunosuppressive therapy. This approach may allow for future widespread application of cell-based therapies. Topics: Bioartificial Organs; C-Peptide; Diabetes Mellitus, Type 1; Diffusion Chambers, Culture; Glucose Tolerance Test; Humans; Immunohistochemistry; Immunosuppression Therapy; Islets of Langerhans Transplantation; Male; Middle Aged; Treatment Outcome | 2013 |
Impaired glucose homeostasis after a transient intermittent hypoxic exposure in neonatal rats.
This initial report presents a neonatal rat model with exposure to a transient intermittent hypoxia (IH), which results in a persisting diabetes-like condition in the young rats. Twenty-five male pups were treated at postnatal day 1 with IH exposure by alternating the level of oxygen between 10.3% and 20.8% for 5h. The treated animals were then maintained in normal ambient oxygen condition for 3 week and compared to age-matched controls. The IH treated animals exhibited a significantly higher fasting glucose level than the control animals (237.00 ± 19.66 mg/dL vs. 167.25 ± 2.95 mg/dL; P=0.003); and a significantly lower insulin level than the control (807.0 ± 72.5 pg/mL vs. 1839.8 ± 377.6 pg/mL; P=0.023). There was no difference in the mass or the number of insulin producing beta cells as well as no indicative of inflammatory changes; however, glucose tolerance tests showed a significantly disturbed glucose homeostasis. In addition, the amount of C-peptide secreted from the islets harvested from the IH animals were decreased significantly (from 914 pM in control to 809 pM in IH; P=0.0006) as well. These observations demonstrate that the neonatal exposure to the IH regimen initiates the development of deregulation in glucose homeostasis without infiltration of inflammatory cells. Topics: Animals; Animals, Newborn; Blood Glucose; C-Peptide; Cell Count; Cell Hypoxia; Diabetes Mellitus, Type 1; Fasting; Homeostasis; Inflammation; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Oxidative Stress; Oxygen; Rats; Rats, Sprague-Dawley | 2013 |
Epidemiological pattern of newly diagnosed children with type 1 diabetes mellitus, Taif, Saudi Arabia.
Type-1-diabetes mellitus (T1DM) is the most commonly diagnosed type of DM in children and adolescents. We aim to identify the epidemiological profile, risk factors, clinical features, and factors related to delayed diagnosis or mismanagement in children with newly diagnosed T1DM in Taif, Saudi Arabia.. Ninety-nine newly diagnosed patients were included in the study along with 110 healthy controls. Patients were classified into 3 groups (I: >2 years, II: 2->6 years, and III: 6-12 years). Both patients and controls were tested for C-peptide, TSH, and autoantibodies associated with DM and those attacking the thyroid gland.. Diabetic ketoacidosis was present in 79.8%. Delayed and missed diagnoses were recorded in 45.5%, with significant correlation to age and district of origin. Severity at presentation showed significant correlation with age and cow's milk feeding. Group I, those with misdiagnosis or positive DM related autoantibodies, had more severe presentations. The correlation of C-peptide and TSH levels in patients and controls was significant for C-peptide and nonsignificant for TSH.. Misdiagnosis and mismanagement are common and account for more severe presentation, especially in young children >2 years. Early introduction of cow's milk appears to be a risk factor for the development of T1DM. Topics: Animals; C-Peptide; Child; Child, Preschool; Delayed Diagnosis; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Humans; Infant; Male; Milk; Risk Factors; Saudi Arabia; Thyrotropin | 2013 |
Comment on: Besser et al. Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes. Diabetes Care 2013;36:195-201.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Humans; Male | 2013 |
Response to comment on: Besser et al. Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes. Diabetes Care 2013;36:195-201.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Humans; Male | 2013 |
Slowly progressive type 1 diabetes treated with metformin for five years after onset.
A 52-year-old man was diagnosed with slowly progressive type 1 diabetes (SPIDDM). We expected him to quickly progress to an insulin-dependent state due to a high anti-glutamic acid decarboxylase antibody titer (23.9 U/mL). At SPIDDM diagnosis, he was in a non-insulin-dependent state, with a fasting serum C-peptide immunoreactivity level of 2.5 ng/mL. Therefore, we prescribed metformin. His glycemic control remained stable, and his intrinsic insulin secretion capacity was maintained for five years. Although one case is insufficient to draw firm conclusions, this report suggests that metformin is a therapeutic choice for SPIDDM when the insulin secretion capacity is maintained. Topics: Autoantibodies; Autoantigens; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Iodide Peroxidase; Iron-Binding Proteins; Male; Metformin; Middle Aged | 2013 |
The prevalence and characteristics of latent autoimmune diabetes in adults (LADA) and its relation with chronic complications in a clinical department of a university hospital in Korea.
Few studies were performed to evaluate the prevalence of latent autoimmune diabetes in adults (LADA) and the difference of chronic complications between LADA, T1DM, and T2DM in Korean. The aim of this study is to establish the prevalence of LADA in a diabetic clinic of Soonchunhyang University hospital and to compare the phenotypic characteristics according to DM classification based on positivity of glutamic acid decarboxylase antibodies (GADA). Also, another important point concerns the occurrence of diabetes chronic microvascular complications in LADA. 323 patients who were checked GADA among diabetic patients admitted at Soonchunhyang University hospital were recruited. Twenty-eight patients (8.7%) were identified as positive for GADA. 11.5% (n = 37) were diagnosed with T1DM and 5.3% (n = 17) were diagnosed with LADA. GADA titer showed significant negative correlation with age of onset, total cholesterol (TC), triglyceride (TG), fasting C-peptide, stimulated C-peptide, BMI, and positive correlation with HbA1C and HDL-C. Compared with those that tested negative for GADA, patients with GADA positive had lower values of onset age, BMI, TC, TG, LDL-C, fasting, and stimulated C-peptide levels and higher values of HbA1C. A significant gradual increase of values was observed for the onset age, BMI, SBP, DBP, fasting, and stimulated C-peptide across the T1DM, LADA, and T2DM subgroups. Concerning the chronic complications there was no difference in prevalence of retinopathy, neuropathy and nephropathy between three groups. Of LADA patients, 12 patients were receiving insulin treatment and mean time to insulin initiation was about 37 months. In conclusion, because our study suggests LADA subgroups in Korea appear to have a faster decline in C-peptide levels, it is worth detecting the patients with LADA early and effort to preserve beta cell function. Furthermore, our results showed that the prevalence of microvascular complication was comparable between the subgroups. Topics: Adult; Age Factors; Autoantibodies; Body Mass Index; C-Peptide; Cholesterol; Cholesterol, HDL; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Glycated Hemoglobin; Hospitals, University; Humans; Hypoglycemic Agents; Insulin; Middle Aged; Republic of Korea; Triglycerides | 2013 |
HLA-associated phenotypes in youth with autoimmune diabetes.
To examine human leukocyte antigen HLA DRB1-DQB1 haplotypes within a multi-ethnic cohort and assess their association with characteristics of diabetes onset.. The sample included 1662 participants from the SEARCH for Diabetes in Youth Study who tested positive for GADA and/or IA-2A autoantibodies. Blood drawn at the study visit was used to measure fasting C-peptide (FCP) and genotype HLA DRB1 and DQB1 loci. Diabetic ketoacidosis (DKA) at diagnosis was determined from medical records. Multivariable linear and logistic regression models stratified by race/ethnicity were used to assess associations with DRB1-DQB1 haplotypes.. The frequency of DRB1*03 susceptibility haplotypes ranged 27.5-28.9% in all racial/ethnic groups. The frequency of susceptibility DRB1*04-DQB1*0302 was higher in non-Hispanic White (NHW; 34.1%) and Hispanic (38.9%) compared to non-Hispanic Black (NHB; 20.8%) youth. Neutral and protective haplotypes were low frequency in all groups. DBR1*03 haplotypes were associated with younger age at diagnosis in NHW and positivity for multiple autoantibodies in Hispanics. DRB1*04-DQB1*0302 haplotypes were associated with multiple autoantibody positivity in NHW and Hispanics, and lower FCP and higher odds of DKA in Hispanics only. Although protective DRB1*04-DQB1*0301 haplotypes were associated with older age at diagnosis in NHW, they were also associated with multiple autoantibody positivity in these youth. Protective DRB1*13 haplotypes were associated with decreased odds of multiple autoantibody positivity in NHB youth.. The distribution of DRB1-DQB1 haplotypes and their association with onset-related characteristics of autoimmune diabetes varies across major racial/ethnic groups in the USA. This may contribute to variation in clinical presentation of autoimmune diabetes by race/ethnicity. Topics: Adolescent; Black People; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Haplotypes; Hispanic or Latino; HLA Antigens; HLA-DQ beta-Chains; HLA-DRB1 Chains; Humans; Male; Phenotype; White People; Young Adult | 2013 |
β- and α-cell dysfunctions in africans with ketosis-prone atypical diabetes during near-normoglycemic remission.
Ketosis-prone atypical diabetes (KPD) is a subtype of diabetes in which the pathophysiology is yet to be unraveled. The aim of this study was to characterize β- and α-cell functions in Africans with KPD during remission.. We characterized β- and α-cell functions in Africans with KPD during remission. The cohort comprised 15 sub-Saharan Africans who had been insulin-free for a median of 6 months. Patients in remission were in good glycemic control (near-normoglycemic) and compared with 15 nondiabetic control subjects matched for age, sex, ethnicity, and BMI. Plasma insulin, C-peptide, and glucagon concentrations were measured in response to oral and intravenous glucose and to combined intravenous arginine and glucose. Early insulin secretion was measured during a 75-g oral glucose tolerance test. Insulin secretion rate and glucagon were assessed in response to intravenous glucose ramping.. Early insulin secretion and maximal insulin secretion rate were lower in patients compared with control participants. In response to combined arginine and glucose stimulation, maximal insulin response was reduced. Glucagon suppression was also decreased in response to oral and intravenous glucose but not in response to arginine and insulin.. Patients with KPD in protracted near-normoglycemic remission have impaired insulin response to oral and intravenous glucose and to arginine, as well as impaired glucagon suppression. Our results suggest that β- and α-cell dysfunctions both contribute to the pathophysiology of KPD. Topics: Adult; Black People; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glucagon; Glucagon-Secreting Cells; Glucose Tolerance Test; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged | 2013 |
Residual beta cell function at diagnosis of type 1 diabetes in children and adolescents varies with gender and season.
There are seasonal variations and gender differences in incidence of type 1 diabetes (T1D), metabolic control and responses to immune interventions at onset of the disease. We hypothesized that there are seasonal and gender differences in residual insulin secretion already at diagnosis of T1D.. In 2005, a national study, the Better Diabetes Diagnosis, was started to classify all newly diagnosed children and adolescents with diabetes. About 95% (3824/4017) of the patients were classified as T1D, and our analyses are based on the patients with T1D.. C-peptide was lower in younger children, 0-10 years of age (0.23 ± 0.20 nmol/L) than in older children, 11-18 years of age (0.34 ± 0.28 nmol/L) (p < 0.000 ). There was a seasonal variation in non-fasting serum C-peptide, significantly correlated to the seasonal variation of diagnosis (p < 0.01). Most children were diagnosed in January, February and March as well as in October when C-peptide was highest, whereas fewer patients were diagnosed in April and May when serum C-peptide was significantly lower (p < 0.01). The seasonal variation of C-peptide was more pronounced in boys than in girls (p < 0.000 and p < 0.01, respectively). Girls had higher C-peptide than boys (p < 0.05), especially in early puberty.. Both seasonal and gender differences in residual beta cell function exist already at diagnosis of T1D. These observations have consequences for treatment and for randomizing patients in immune intervention clinical trials. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infant; Insulin-Secreting Cells; Male; Prospective Studies; Seasons; Sex Characteristics | 2013 |
Frequency, immunogenetics, and clinical characteristics of latent autoimmune diabetes in China (LADA China study): a nationwide, multicenter, clinic-based cross-sectional study.
Adult non-insulin requiring diabetes includes latent autoimmune diabetes of adults (LADA), distinguished from type 2 diabetes by the presence of islet autoantibodies. LADA China determined the characteristics of Chinese LADA. This nationwide, multicenter, clinic-based cross-sectional study was conducted in 46 university-affiliated hospitals in 25 Chinese cities. All 4,880 ketosis-free diabetic patients (<1 year postdiagnosis, without insulin therapy for >6 months, aged ≥30 years) had GAD antibody (GADA) and HLA-DQ genotype measured centrally with clinical data collected locally. GADA-positive subjects were classified as LADA. Of the patients, 5.9% were GADA positive with LADA. LADA showed a north-south gradient. Compared with GADA-negative type 2 diabetes, LADA patients were leaner, with lower fasting C-peptide and less metabolic syndrome. Patients with high GADA titers are phenotypically different from those with low GADA titers, while only a higher HDL distinguished the latter from those with type 2 diabetes. HLA diabetes-susceptible haplotypes were more frequent in LADA, even in those with low-titer GADA. HLA diabetes-protective haplotypes were less frequent in LADA. Our study implicates universal immunogenetic effects, with some ethnic differences, in adult-onset autoimmune diabetes. Autoantibody positivity and titer could be important for LADA risk stratification and accurate therapeutic choice in clinical practice. Topics: Adult; Autoantibodies; C-Peptide; China; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Glutamate Decarboxylase; Haplotypes; HLA-DQ Antigens; Humans; Lipoproteins, HDL; Male; Metabolic Syndrome; Middle Aged; Prediabetic State; Risk | 2013 |
RD Lawrence lecture 2012: assessing aetiology in diabetes: how C-peptide, CRP and fucosylation came to the party!
Assigning the correct aetiology in diabetes is important for treatment, understanding prognosis and for follow-up of family members. Despite these benefits, many are missing out on the opportunity to have testing for monogenic forms of diabetes. This review gives the clinical features of the commoner forms of monogenic diabetes and examines which clinical and biological markers can be used to identify those at highest risk of having Maturity onset diabetes of the young (MODY). MODY is characterised by young-onset, familial diabetes which is C-peptide positive, β-cell antibody negative and not associated with metabolic syndrome. Differentiating from type 1 and type 2 diabetes can be challenging due to the overlap of clinical features. In type 1 diabetes, insulin production ceases after the honeymoon period. Thus C-peptide can be used to detect those with persisting insulin secretion who might have a different cause for their diabetes. In type 2 diabetes, most have insulin resistance, so absence of metabolic syndrome could be used to identify those most likely to have MODY. Another approach is to look for non-pancreatic features associated with mutations in MODY genes. Following results from Genome-wide association studies, we have shown that those with HNF1A mutations (the commonest form of MODY) have decreased serum levels of highly-sensitive C-reactive protein (hsCRP) and altered patterns of plasma protein fucosylation. These features can differentiate HNF1A-MODY from common forms of diabetes with a high degree of discriminative accuracy. Using combinations of clinical features and new biomarkers in diagnostic pathways will help increase diagnosis rates of MODY. Topics: Adolescent; Adult; Age of Onset; Biomarkers; C-Peptide; C-Reactive Protein; Child; Delayed Diagnosis; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fucose; Genetic Testing; Genotype; Glucokinase; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 4; Humans; Patient Selection; Young Adult | 2013 |
Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes.
Mixed-meal tolerance test (MMTT) area under the curve C-peptide (AUC CP) is the gold-standard measure of endogenous insulin secretion in type 1 diabetes but is intensive and invasive to perform. The 90-min MMTT-stimulated CP ≥0.2 nmol/L (90CP) is related to improved clinical outcomes, and CP ≥0.1 nmol/L is the equivalent fasting measure (FCP). We assessed whether 90CP or FCP are alternatives to a full MMTT.. CP was measured during 1,334 MMTTs in 421 type 1 diabetes patients aged <18 years at 3, 9, 18, 48, and 72 months duration. We assessed: 1) correlation between mean AUC CP and 90CP or FCP; 2) sensitivity and specificity of 90CP ≥0.2 nmol/L and FCP ≥ 0.1 nmol/L to detect peak CP ≥0.2 nmol/L and the equivalent AUC CP; and 3) how the time taken to reach the CP peak varied with age of diagnosis and diabetes duration.. AUC CP was highly correlated to 90CP (r(s) = 0.96; P < 0.0001) and strongly correlated to FCP (r(s) = 0.84; P < 0.0001). AUC CP ≥23 nmol/L/150 min was the equivalent cutoff for peak CP ≥0.2 nmol/L (98% sensitivity/97% specificity). A 90CP ≥0.2 nmol/L correctly classified 96% patients using AUC or peak CP, whereas FCP ≥0.1 nmol/L classified 83 and 85% patients, respectively. There was only a small difference seen between peak and 90CP (median 0.02 nmol/L). The CP peak occurred earlier in patients with longer diabetes duration (6.1 min each 1-year increase in duration) and younger age (2.5 min each 1-year increase).. 90CP is a highly sensitive and specific measure of AUC and peak CP in children and adolescents with type 1 diabetes and offers a practical alternative to a full MMTT. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Fasting; Female; Humans; Male; Postprandial Period | 2013 |
Islet autotransplantation to preserve beta cell mass in selected patients with chronic pancreatitis and diabetes mellitus undergoing total pancreatectomy.
Islet autotransplantation (IAT) is performed in nondiabetic patients with chronic pancreatitis at the time of total pancreatectomy (TP) to minimize risk of postoperative diabetes. The role of TP-IAT in patients with chronic pancreatitis and C-peptide-positive diabetes is not established. We postulate that IAT can preserve beta cell mass and thereby benefit patients with preexisting diabetes undergoing TP.. Preoperative metabolic testing, islet isolation outcomes, and subsequent islet graft function were reviewed for 27 patients with diabetes mellitus and chronic pancreatitis undergoing TP-IAT. The relationships between the results of preoperative metabolic testing and islet isolation outcomes were explored using regression analysis.. Mean islet yield was 2060 (SD, 2408) islet equivalents/kg. Peak C-peptide (from mixed meal tolerance testing) was the strongest predictor of islet yield, with higher stimulated C-peptide levels associated with greater islet mass. Half of the patients who had C-peptide levels measured after transplantation demonstrated C-peptide production at a level that conveys protective benefit in type 1 diabetes (≥ 0.6 ng/mL).. These findings provide proof of concept that significant islet mass can be isolated in patients with chronic pancreatitis and C-peptide-positive diabetes mellitus undergoing TP-IAT. Stimulated C-peptide may be a useful marker of islet mass before transplantation in these patients. Topics: Adolescent; Adult; Aged; Biomarkers; Blood Glucose; C-Peptide; Chi-Square Distribution; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Male; Middle Aged; Pancreatectomy; Pancreatitis, Chronic; Transplantation, Autologous; Treatment Outcome; Young Adult | 2013 |
Family history of Type 1 diabetes affects insulin secretion in patients with 'Type 2' diabetes.
The aim was to evaluate the impact of family history of diabetes on the phenotype of patients diagnosed with Type 2 diabetes and the frequency of susceptibility genotypes.. Patients with Type 2 diabetes with family history for both Type 1 and Type 2 diabetes (FH(MIX, n) = 196) or Type 2 diabetes only (FH(T2), n = 139) matched for age, sex, BMI and age at diagnosis, underwent an oral glucose tolerance test and a combined glucagon test and insulin tolerance test. Glutamic acid decarboxylase (GAD) antibodies and major Type 1 and Type 2 diabetes susceptibility gene variants were analysed. Patients were stratified into groups according to family history or GAD antibody positivity (GADA+, GADA-) or a combination of these (GADA+/FH(MIX), GADA+/FH(T2), GADA-/FH(MIX), GADA-/FH(T2)).. Compared with other patients, those with FH(MIX) more often had GAD antibodies (14.3 vs. 4.3%, P = 0.003), and those with both FH(MIX) and GAD antibodies had the highest frequency of insulin deficiency (stimulated serum C-peptide < 0.7 nmol/l, GADA+/FH(MIX) 46.4% vs. GADA-/FH(MIX) 9.5% (P < 0.00001), GADA-/FH(T2) 4.5% (P < 0.00001), GADA+/FH(T2) 0%). Patients with GADA+/FH(MIX) more often had HLA-DQB1 risk genotypes compared with patients with GADA-/FH(MIX) or GADA-/FH(T2D) (47 vs. 23 or 14%, P = 0.05 and P < 0.00001, respectively). In logistic regression analyses, FH(MIX), GAD antibody positivity and HLA risk genotypes were independently associated with insulin deficiency.. A family history for both type 1 and type 2 diabetes was associated with higher prevalence of GAD antibodies and HLA-DQB1 risk genotypes than a family history of type 2 diabetes only, and was associated with earlier and more severe development of insulin deficiency, which was only partially explained by GAD antibodies and HLA. Topics: Adolescent; Adult; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Finland; Genetic Predisposition to Disease; Genotype; Glucose Tolerance Test; Glutamate Decarboxylase; HLA Antigens; Humans; Insulin; Insulin Secretion; Male; Mass Screening; Middle Aged; Phenotype | 2013 |
Serum adipokines as biomarkers of beta-cell function in patients with type 1 diabetes: positive association with leptin and resistin and negative association with adiponectin.
We investigated the adipokines adiponectin, leptin and resistin as serum biomarkers of beta-cell function in patients with type 1 diabetes.. One hundred and eighteen patients with type 1 diabetes (20.3 ± 7.5 years) diagnosed <5 years underwent standardized mixed meal test (MMTT) for 2 h. Systemic concentrations of C-peptide, adiponectin, leptin and resistin obtained during MMTT were measured and compared between patient groups by multiple regression analysis.. Patients were divided by their adipokine levels in subgroups above or below the median level ('high versus low'). High adiponectin levels (>10.6 µg/mL) were associated with lower C-peptide compared to the low adiponectin subgroup (p < 0.03). Increased leptin or resistin concentrations associated positively with beta-cell function even after adjustment for metabolic confounders (p < 0.04). The described associations between adipokines and C-peptide concentrations persisted in Spearman correlation tests (p < 0.05). Serum adipokines fell during MMTT (p < 0.05).. Serum adipokine levels differentially correlate with beta-cell function in type 1 diabetes independent of BMI or metabolic control. Serum adipokines should be investigated as biomarkers of beta-cell function in prospective studies and intervention trials in type 1 diabetes. Topics: Adiponectin; Adolescent; Adult; Biomarkers; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Humans; Insulin-Secreting Cells; Leptin; Male; Meals; Resistin | 2013 |
Home urine C-peptide creatinine ratio (UCPCR) testing can identify type 2 and MODY in pediatric diabetes.
Making the correct diabetes diagnosis in children is crucial for lifelong management. Type 2 diabetes and maturity onset diabetes of the young (MODY) are seen in the pediatric setting, and can be difficult to discriminate from type 1 diabetes. Postprandial urinary C-peptide creatinine ratio (UCPCR) is a non-invasive measure of endogenous insulin secretion that has not been tested as a diagnostic tool in children or in patients with diabetes duration <5 yr. We aimed to assess whether UCPCR can discriminate type 1 diabetes from MODY and type 2 in pediatric diabetes.. Two-hour postprandial UCPCR was measured in 264 patients aged <21 yr (type 1, n = 160; type 2, n = 41; and MODY, n = 63). Receiver operating characteristic curves were used to identify the optimal UCPCR cutoff for discriminating diabetes subtypes.. UCPCR was lower in type 1 diabetes [0.05 (<0.03-0.39) nmol/mmol median (interquartile range)] than in type 2 diabetes [4.01 (2.84-5.74) nmol/mmol, p < 0.0001] and MODY [3.51 (2.37-5.32) nmol/mmol, p < 0.0001]. UCPCR was similar in type 2 diabetes and MODY (p = 0.25), so patients were combined for subsequent analyses. After 2-yr duration, UCPCR ≥ 0.7 nmol/mmol has 100% sensitivity [95% confidence interval (CI): 92-100] and 97% specificity (95% CI: 91-99) for identifying non-type 1 (MODY + type 2 diabetes) from type 1 diabetes [area under the curve (AUC) 0.997]. UCPCR was poor at discriminating MODY from type 2 diabetes (AUC 0.57).. UCPCR testing can be used in diabetes duration greater than 2 yr to identify pediatric patients with non-type 1 diabetes. UCPCR testing is a practical non-invasive method for use in the pediatric outpatient setting. Topics: Adolescent; Algorithms; C-Peptide; Child; Cohort Studies; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Disease Progression; Down-Regulation; Family; Female; Humans; Male; Outpatient Clinics, Hospital; Postprandial Period; Self Care; Sensitivity and Specificity; United Kingdom | 2013 |
Continuous C-peptide loss in patients with type 1 diabetes and multiethnic background.
C peptide (CP) was evaluated in 88 individuals with type 1 diabetes, variable disease duration and multiethnic background. Initially, 28 patients had detectable CP, which persisted in 46.2% after 17.4±4 months. CP decline was associated with ethnicity, HbA1c and baseline CP, but not with GADA, PTPN22 or insulin gene polymorphisms. Topics: Adolescent; Adult; Age of Onset; Black People; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male; White People | 2013 |
Establishment of a stringent large animal model of insulin-dependent diabetes for islet autotransplantation: combination of pancreatectomy and streptozotocin.
A stringent porcine islet autograft diabetes model was developed to enable the assessment of autoislet safety and efficacy in either portal vein or an extrahepatic site.. A 95% pancreatectomy was performed preserving the pancreaticoduodenal arcade; however, glycemic control was still maintained at 3.3 ± 0.3 days (mean ± SEM), shown by euglycemic fasting blood glucose levels of 4.9 ± 0.8 mmol/L (mean ± SEM, n = 3). To reduce surgical complications and eliminate remaining islets, pigs were dosed intravenously after a modified 90% pancreatectomy, with 150-mg/kg streptozotocin, producing a diabetic state (18.9 ± 1.8 mmol/L [mean ± SEM], n = 8; P < 0.001) within 2.0 ± 0.9 days (mean ± SEM).. Animals presented with sustained hyperglycemia, failing a glucose challenge test 12 weeks after diabetic induction, and showed no stimulated C-peptide secretion compared to nondiabetic controls (baseline: 0.479 ± 0.080 ng/mL [mean ± SEM] vs after procedure: 0.219 ± 0.055 ng/mL [mean ± SEM], P = 0.02). Diabetic animals were maintained on daily insulin. Despite an initial decline in body weight acutely after pancreatectomy and streptozotocin administration, the mean body weight increased after induction over the approximately 88-day study, indicating that the animals were in good health.. This stringent porcine model of diabetic induction should be used to assess autograft transplantation safety and efficacy. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Pancreatectomy; Streptozocin; Swine; Swine, Miniature; Time Factors; Transplantation, Autologous | 2013 |
HLA class II gene associations in African American type 1 diabetes reveal a protective HLA-DRB1*03 haplotype.
Owing to strong linkage disequilibrium between markers, pinpointing disease associations within genetic regions is difficult in European ancestral populations, most notably the very strong association of the HLA-DRB1*03-DQA1*05:01-DQB1*02:01 haplotype with Type 1 diabetes risk, which is assumed to be because of a combination of HLA-DRB1 and HLA-DQB1. In contrast, populations of African ancestry have greater haplotype diversity, offering the possibility of narrowing down regions and strengthening support for a particular gene in a region being causal. We aimed to study the human leukocyte antigen (HLA) region in African American Type 1 diabetes.. Two hundred and twenty-seven African American patients with Type 1 diabetes and 471 African American control subjects were tested for association at the HLA class II genes, HLA-DRB1, HLA-DQA1, HLA-DQB1 and 5147 single nucleotide polymorphisms across the major histocompatibility complex region using logistic regression models. Population admixture was accounted for with principal components analysis.. Single nucleotide polymorphism marker associations were explained by the HLA associations, with the major peak over the class II loci. The HLA association overall was extremely strong, as expected for Type 1 diabetes, even in African Americans in whom diabetes diagnosis is heterogeneous. In addition, there were unique features: the HLA-DRB1*03 haplotype was split into HLA-DRB1*03:01, which confers greatest susceptibility in these samples (odds ratio 3.17, 95% CI 1.72-5.83) and HLA-DRB1*03:02, an allele rarely observed in Europeans, which confers the greatest protection in these African American samples (odds ratio 0.22, 95% CI 0.09-0.55).. The unique diversity of the African HLA region we have uncovered supports a specific and major role for HLA-DRB1 in HLA-DRB1*03 haplotype-associated Type 1 diabetes risk. Topics: Adolescent; Alleles; Black or African American; C-Peptide; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genes, MHC Class II; Genetic Predisposition to Disease; Genome-Wide Association Study; HLA-DRB1 Chains; Humans; Linkage Disequilibrium; Logistic Models; Male; New Jersey; Oligonucleotide Array Sequence Analysis; Polymorphism, Single Nucleotide; Principal Component Analysis | 2013 |
Unequal contribution of familial factors to autoimmunity and clinical course of childhood diabetes.
collection of family history of diabetes mellitus (DM) is commonly performed when this illness is diagnosed in children. However the significance of gleaned information may differ depending on the affected family members.. this study was performed in order to describe detailed familial history of DM in patients and to evaluate the impact of it on the natural course of childhood DM.. After exclusion of patients with confirmed monogenic basis of the disease or type 2 diabetes, the study group numbered 989 diabetic children. The data on detailed family history of DM among the first- and second- degree relatives, age at the onset of DM, recent percentage of glycated hemoglobin (HbA1c), presence of diabetes-related antibodies and the highest observed fasting c-peptide level were collected.. Having siblings with DM was linked to early onset of diabetes in the study group (mean difference -2.83 95% confidence interval [cI] -4.24 to -1.42). Dominant mode of inheritance, particularly from the maternal side was significantly associated with diabetes onset at an older age. Children of diabetic mothers developed diabetes at a mean age of 10.83 in comparison to those without family history of DM - 8.75 years (p=0.0228). However, children whose mothers had any type of DM, had a significantly higher level of glycated hemoglobin than the others (8.34 vs 7.56%, p=0.0315). Additionally, a rising number of units of the family tree affected by any type of diabetes was associated with later onset of diabetes in children (p for trend = 0.0452).. Familial factors influence the natural course of childhood diabetes, but their contribution is not equal, showing more pronounced effects of maternal factors. Topics: Age of Onset; Autoimmunity; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Genetic Testing; Glycated Hemoglobin; Humans; Male; Medical History Taking; Pedigree; Poland | 2012 |
Secretory unit of islet transplant objects (SUITO) index can predict severity of hypoglycemic episodes in clinical islet cell transplantation.
One endpoint of clinical islet cell transplantation for type 1 diabetic patients is the elimination or reduction of hypoglycemia. We previously developed a simple tool to evaluate islet graft function: the secretory unit of islet transplant objects (SUITO) index. The aim of this study is to clarify the association between the SUITO index and hypoglycemic episodes. Data from 310 clinical evaluations of 11 islet recipients were included in this study. Fasting plasma C-peptide and glucose levels were measured at every evaluation. The SUITO index was calculated according to the following formula: 1500 × C-peptide level (ng/ml)/[blood glucose level (mg/dl) - 63]. The number of hypoglycemic events (<3.8 mmol/L) and severe hypoglycemic events (<2.2 mmol/L or hypoglycemic unawareness) was assessed on the basis of interviews and self-monitoring of blood glucose (SMBG). Receiver operating characteristic (ROC) analysis was performed to determine the cut-off values of the SUITO index for hypoglycemic events. Based on the ROC study, follow-up data after transplantations were divided into the following three groups: low-SUITO (SUITO index <10, n = 91), middle-SUITO (10 ≤SUITO index <26, n = 83), high-SUITO (SUITO index ≤26, n = 125). The frequency of total hypoglycemia in the high-SUITO group was significantly decreased when compared to the other groups (value with Kruskal-Wallis test p < 0.001). The frequency of total severe hypoglycemia was significantly decreased in the low-SUITO group compared to pretransplant status and further decreased in the middle- and high-SUITO group. Spearman correlation coefficients were -0.663 (p < 0.001) between the number of total hypoglycemic events per one month and the SUITO index and -0.521 (p < 0.001) between that of severe events and the SUITO index. The SUITO index could predict the severity of hypoglycemic episodes in type 1 diabetic patients who received islet cell transplantations. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; ROC Curve; Treatment Outcome | 2012 |
C-peptide in the classification of diabetes in children and adolescents.
To report C-peptide results in newly diagnosed patients and the relation to clinical diagnosis of diabetes.. A nation-wide cohort, the Better Diabetes Diagnosis study was used to determine serum C-peptide at diagnosis in 2734 children and adolescents. Clinical data were collected at diagnosis and follow-up. C-peptide was determined in a validated and controlled time-resolved fluoroimmunoassay.. The clinical classification of diabetes, before any information on human leukocyte antigen, islet autoantibodies, or C-peptide was received, was type 1 diabetes (T1D) in 93%, type 2 diabetes (T2D) in 1.9%, maturity onset diabetes of the young (MODY) in 0.8%, secondary diabetes (0.6%), while 3.3% could not be classified. In a random, non-fasting serum sample at diagnosis, 56% of the patients had a C-peptide value >0.2 nmol/L. Children classified as T2D had the highest mean C-peptide (1.83 + 1.23 nmol/L) followed by MODY (1.04 ± 0.71 nmol/L) and T1D (0.28 ± 0.25 nmol/L). Only 1/1037 children who had C-peptide <0.2 nmol/L at diagnosis was classified with a type of diabetes other than T1D. Predictive value of C-peptide >1.0 nmol/L for the classification of either T2D or MODY was 0.46 [confidence interval 0.37-0.58].. More than half of children with newly diagnosed diabetes have clinically important residual beta-cell function. As the clinical diagnosis is not always straightforward, a random C-peptide taken at diagnosis may help to classify diabetes. There is an obvious use for C-peptide determinations to evaluate beta-cell function in children with diabetes. Topics: Adolescent; Age of Onset; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnostic Techniques, Endocrine; Female; Humans; Infant; Infant, Newborn; Male; Osmolar Concentration; Predictive Value of Tests | 2012 |
The -1123G>C variant of PTPN22 gene promoter is associated with latent autoimmune diabetes in adult Chinese Hans.
The protein tyrosine phosphatase non-receptor 22 (PTPN22) gene encodes for lymphoid protein tyrosine phosphatase. Recent studies demonstrated the association between the +1858T, -1123G>C variants of PTPN22 gene and type 1 diabetes mellitus in Caucasian and Japanese populations. This study examined the relationship between the polymorphism of PTPN22 gene and latent autoimmune 1 diabetes in adults (LADA) in Chinese Hans. We studied 229 adult Chinese patients with LADA (LADA group) and 210 healthy volunteers (control group). The -1123G>C and +1858C>T polymorphisms of PTPN22 gene were determined by PCR-restriction fragment length polymorphism method. Further, genotypic/allelic frequencies and clinical characteristics were compared between two groups. There was a significant difference of frequencies of the -1123G>C polymorphism between LADA and control groups (OR = 1.99, 95% CI = 1.24-3.2; P = 0.001). However, no significant differences in the +1858C>T genotypic (CC, CT) and allelic (C, T) frequencies were found. Furthermore, the frequencies of the -1123 GC, CC genotype in male patients with LADA were significantly higher compared with male healthy volunteers (OR = 1.65, 95% CI = 1.21-2.26; P = 0.005). The analysis of covariance demonstrated no difference between glycosylated hemoglobin, body mass index, duration of diabetes, C-peptide, and GAD-Ab titer between the group carrying GC/CC and the group without allele C. In conclusion, the -1123G>C promoter polymorphism of PTPN22 gene, but not the +1858C>T variant, is associated with LADA in adult Chinese Hans. Topics: Adult; Aged; Alleles; Asian People; Body Mass Index; C-Peptide; China; Diabetes Mellitus, Type 1; Exons; Female; Gene Frequency; Genotype; Hemoglobins, Abnormal; Humans; Male; Middle Aged; Polymorphism, Single Nucleotide; Promoter Regions, Genetic; Protein Tyrosine Phosphatase, Non-Receptor Type 22 | 2012 |
Determinants of undercarboxylated and carboxylated osteocalcin concentrations in type 1 diabetes.
To determine whether undercarboxylated osteocalcin (UC-OC) or gamma-carboxyglutamic-carboxylated-type osteocalcin (GLA-OC) concentrations deviate from normal in type 1 diabetes (T1D), serum levels were compared between 115 subjects with T1D and 55 age-matched healthy controls. UC-OC and GLA-OC concentrations were similar between groups; however, in T1D, UC-OC correlated positively with markers of insulin exposure, either endogenously produced or exogenously administered.. A study was conducted to determine whether dysregulation of circulating concentrations of UC-OC or GLA-OC occurs in patients with type 1 diabetes, a condition of insulin deficiency without insulin resistance.. We measured serum concentrations of UC-OC and GLA-OC in 115 subjects with T1D, ages 14-40 years, and in 55 age-matched healthy control subjects. Relationships between UC-OC and GLA-OC concentrations and patient characteristics (gender and age), indices of glycemic control (hemoglobin A1c (HbA1c), fasting plasma glucose, C-peptide concentration, 3-day average glucose measured by a continuous glucose sensor, total daily insulin dose) and circulating indices of skeletal homeostasis (total calcium, 25-OH vitamin D, parathyroid hormone, insulin-like growth factor 1 (IGF-1), type 1 collagen degradation fragments (CTX), adiponectin, leptin) were examined. Between group differences in the concentrations of UC-OC and GLA-OC were the main outcome measures.. Although adiponectin levels were higher in the T1D group, between-group comparisons did not reveal statistically significant differences in concentration of UC-OC, GLA-OC, CTX or leptin between the T1D and control populations. Instead, by multivariate regression modeling, UC-OC was correlated with younger age (p < 0.001), higher CTX (p < 0.001), lower HbA1c (p = 0.013), and higher IGF-1 (p = 0.086). Moreover, within the T1D subgroup, UC-OC was positively correlated with C-peptide/glucose ratio (reflecting endogenous insulin secretion), with IGF-1 (reflecting intra-portal insulin sufficiency), and with total daily insulin dose.. In T1D, UC-OC appears to correlate positively with markers of insulin exposure, either endogenously produced or exogenously administered. Topics: Adiponectin; Adolescent; Adult; Biomarkers; Blood Glucose; C-Peptide; Case-Control Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Leptin; Male; Osteocalcin; Young Adult | 2012 |
Proinsulin, GLP-1, and glucagon are associated with partial remission in children and adolescents with newly diagnosed type 1 diabetes.
Proinsulin is a marker of beta-cell distress and dysfunction in type 2 diabetes and transplanted islets. Proinsulin levels are elevated in patients newly diagnosed with type 1 diabetes. Our aim was to assess the relationship between proinsulin, insulin dose-adjusted haemoglobin A1c (IDAA1C), glucagon-like peptide-1 (GLP-1), glucagon, and remission status the first year after diagnosis of type 1 diabetes.. Juvenile patients (n = 275) were followed 1, 6, and 12 months after diagnosis. At each visit, partial remission was defined as IDAA1C ≤ 9%. The patients had a liquid meal test at the 1-, 6-, and 12-month visits, which included measurement of C-peptide, proinsulin, GLP-1, glucagon, and insulin antibodies (IA).. Patients in remission at 6 and 12 months had significantly higher levels of proinsulin compared to non-remitting patients (p < 0.0001, p = 0.0002). An inverse association between proinsulin and IDAA1C was found at 1 and 6 months (p = 0.0008, p = 0.0022). Proinsulin was positively associated with C-peptide (p < 0.0001) and IA (p = 0.0024, p = 0.0068, p < 0.0001) at 1, 6, and 12 months. Glucagon (p < 0.0001 and p < 0.02) as well as GLP-1 (p = 0.0001 and p = 0.002) were significantly lower in remitters than in non-remitters at 6 and 12 months. Proinsulin associated positively with GLP-1 at 1 month (p = 0.004) and negatively at 6 (p = 0.002) and 12 months (p = 0.0002).. In type 1 diabetes, patients in partial remission have higher levels of proinsulin together with lower levels of GLP-1 and glucagon compared to patients not in remission. In new onset type 1 diabetes proinsulin level may be a sign of better residual beta-cell function. Topics: Adolescent; Age of Onset; Blood Glucose; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glucagon-Like Peptide 1; Humans; Infant; Infant, Newborn; Male; Proinsulin; Remission, Spontaneous | 2012 |
Association between age, IL-10, IFNγ, stimulated C-peptide and disease progression in children with newly diagnosed Type 1 diabetes.
The relation of disease progression and age, serum interleukin 10 (IL-10) and interferon gamma (IFNγ) and their genetic correlates were studied in paediatric patients with newly diagnosed Type 1 diabetes.. Two hundred and twenty-seven patients from the Hvidoere Study Group were classified in four different progression groups as assessed by change in stimulated C-peptide from 1 to 6 months. CA repeat variants of the IL-10 and IFNγ gene were genotyped and serum levels of IL-10 and IFNγ were measured at 1, 6 and 12 months.. IL-10 decreased (P < 0.001) by 7.7% (1 month), 10.4% (6 months) and 8.6% (12 months) per year increase in age of child, while a twofold higher C-peptide concentration at 1 month (p = 0.06), 6 months (P = 0.0003) and 12 months (P = 0.02) was associated with 9.7%, 18.6% and 9.7% lower IL-10 levels, independent of each other. IL-10 concentrations did not associate with the disease progression groups. By contrast, IFNγ concentrations differed between the four progression groups at 6 and 12 months (P = 0.02 and P = 0.01, respectively); patients with rapid progressing disease had the highest levels at both time points. Distribution of IL-10 and IFNγ genotypes was equal among patients from the progression groups.. IL-10 serum levels associate inversely with age and C-peptide. As age and C-peptide also associate, a triangular association is proposed. Genetic influence on IL-10 production seems to be masked by distinct disease mechanisms. Increased serum IFNγ concentrations associate with rapid disease progression. Functional genetic variants do not associate with a single progression pattern group, implying that disease processes override genetically predisposed cytokine production. Topics: Adolescent; Aging; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Fasting; Female; Genetic Predisposition to Disease; Humans; Infant; Interferon-gamma; Interleukin-10; Male | 2012 |
Gene CNVs and protein levels of complement C4A and C4B as novel biomarkers for partial disease remissions in new-onset type 1 diabetes patients.
To determine the roles of complement C4A and C4B gene copy-number variations and their plasma protein concentrations in residual insulin secretion and loss of pancreatic β-cell function in new-onset type 1 diabetes (T1D) patients.. We studied 34 patients of European ancestry with new-onset T1D, aged between 3 and 17 yr (10.7 ± 3.45), at Nationwide Children's Hospital in Columbus, Ohio. Gene copy-number and size variations of complement C4A and C4B were determined by genomic Southern blot analyses. C4A and C4B protein phenotypes were elucidated by immunofixation and radial immunodiffusion. Two-digit human leukocyte antigen (HLA)-DRB1 genotypes were determined by sequence-specific polymerase chain reaction. At 1- and 9-month post diagnosis, stimulated C-peptide levels were measured after a standardized mixed-meal tolerance test.. The diploid gene copy-numbers of C4A varied from 0 to 4, and those of C4B from 0 to 3. Patients with higher copy-number of C4A or higher C4A plasma protein concentrations at diagnosis had higher C-peptide levels at 1-month post diagnosis (p = 0.008; p = 0.008). When controlled by the Z-score of body mass index, C4A copy-numbers, C4A protein concentrations, the age of disease onset, and the number of HLA-DR3 but not DR4 alleles were significant parameters in determining C-peptide levels. At 9-month post diagnosis, 42.3% of patients remained in partial remission, and these patients were characterized by lower total C4B copy-numbers or lower C4B protein concentrations (p = 0.02; p = 0.0004).. C4A appears to associate with the protection of residual β-cell function in new-onset T1D; C4B is correlated with the end of disease remission at 9-month post diagnosis. Topics: Adolescent; Biomarkers; C-Peptide; Child; Child, Preschool; Complement C4a; Complement C4b; Diabetes Mellitus, Type 1; DNA Copy Number Variations; Female; Gene Dosage; HLA-DR3 Antigen; Humans; Insulin-Secreting Cells; Male; Recovery of Function; White People | 2012 |
Slowly progressive insulin-dependent diabetes in a patient with primary biliary cirrhosis with portal hypertension-type progression.
A 73-year-old woman had previously been diagnosed with CREST syndrome, PBC and diabetes. Hepatic fibrosis was not evident, in spite of the transudative ascites and active esophageal varices. ACA were positive, whereas AMA and anti-gp210 antibodies were negative. She showed low urinary excretion of C-peptide and was weakly positive for anti-GAD antibody. She was diagnosed with a form of PBC that progresses via portal hypertension rather than liver failure and with SPIDDM. Her HLA type did not contain risk allele for IDDM or PBC. SPIDDM should be considered when patients with PBC with portal hypertension-type progression develop diabetes. Topics: Aged; C-Peptide; CREST Syndrome; Diabetes Mellitus, Type 1; Disease Progression; Female; Histocompatibility Testing; Humans; Hypertension, Portal; Liver Cirrhosis, Biliary; Polyendocrinopathies, Autoimmune | 2012 |
Low expression and secretion of circulating soluble CTLA-4 in peripheral blood mononuclear cells and sera from type 1 diabetic children.
High levels of soluble cytotoxic T-lymphocyte antigen 4 (soluble CTLA-4), an alternative splice form of the regulatory T-cell (Treg) associated CTLA-4 gene, have been associated with type 1 diabetes (T1D) and other autoimmune diseases, such as Grave's disease and myasthenia gravis. At the same time, studies have shown soluble CTLA-4 to inhibit T-cell activation through B7 binding. This study aimed to investigate the role of soluble CTLA-4 in relation to full-length CTLA-4 and other Treg-associated markers in T1D children and in individuals with high or low risk of developing the disease.. T1D children were studied at 4 days, 1 and 2 years after diagnosis in comparison to individuals with high or low risk of developing the disease. Isolated peripheral blood mononuclear cells were stimulated with the T1D-associated glutamic acid decarboxylase 65 and phytohaemagglutinin. Subsequently, soluble CTLA-4, full-length CTLA-4, FOXP3 and TGF-β mRNA transcription were quantified and protein concentrations of soluble CTLA-4 were measured in culture supernatant and sera.. Low protein concentrations of circulating soluble CTLA-4 and a positive correlation between soluble CTLA-4 mRNA and protein were seen in T1D, in parallel with a negative correlation in healthy subjects. Further, low levels of mitogen-induced soluble CTLA-4 were accompanied by low C-peptide levels. Interestingly, low mitogen-induced soluble CTLA-4 mRNA and low TGF-β mRNA expression were seen in high risk individuals, suggesting an alteration in activation and down-regulating immune mechanisms during the pre-diabetic phase. Topics: Adolescent; Autoimmunity; Biomarkers; Blood Cells; C-Peptide; Child; Child, Preschool; CTLA-4 Antigen; Diabetes Mellitus, Type 1; Female; Forkhead Transcription Factors; Gene Expression; Humans; Longitudinal Studies; Male; Protein Isoforms; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; T-Lymphocytes, Regulatory; Transcription, Genetic; Transforming Growth Factor beta | 2012 |
Insulin sensitivity after maximal and endurance resistance training.
The purpose of the study was to compare the effects of maximal resistance training (MRT) vs. endurance resistance training (ERT) on improvements in insulin levels and glucose tolerance in overweight individuals at risk of developing type 2 diabetes. Eighteen participants with baseline values suggesting impaired glucose tolerance were randomly assigned to 1 of 2 groups. Group 1 engaged in supervised MRT (Bernstein inverted pyramid system: 5 × 3-4, 60-85% 1 repetition maximum [1RM]), 3 d·wk(-1) over 4 months, whereas members of group 2 acted as controls. Later, group 2 engaged in supervised ERT (3 × 12-15, 45-65% 1RM), 3 d·wk(-1) over a 4 month period with the 2 prebaselines as controls. Both interventions consisted of 8 exercises that included the entire body. Glucose (fasting and 2-hour test), insulin and C-peptide measures were assessed from pre to post in both groups. The MRT led to reduced blood levels of 2-hour glucose (p = 0.044) and fasting C-peptide (p = 0.023) and decreased insulin resistance (p = 0.040). The ERT caused a significant reduction in the blood levels of insulin (p = 0.023) and concomitant positive effects on % insulin sensitivity (p = 0.054) and beta-cell function (p = 0.020). The findings indicate that both MRT and ERT lead to decreased insulin resistance in people with a risk of developing type 2 diabetes; MRT led to a greater increase in glucose uptake capacity (in muscles), whereas ERT led to greater insulin sensitivity, supporting the recommendation of both MRT and ERT as primary intervention approaches for individuals at a risk of developing type 2 diabetes. Topics: Adult; Aged; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Male; Middle Aged; Overweight; Physical Endurance; Random Allocation; Resistance Training | 2012 |
Transplanted functional islet mass: donor, islet preparation, and recipient factors influence early graft function in islet-after-kidney patients.
The ability to predict clinical function of a specific islet batch released for clinical transplantation using standardized variables remains an elusive goal.. Analysis of 10 donor, 7 islet isolation, 3 quality control, and 6 recipient variables was undertaken in 110 islet-after-kidney transplants and correlated to the pre- to 28-day posttransplant change in C-peptide to glucose and creatinine ratio (ΔCP/GCr).. Univariate analysis yielded islet volume transplanted (Spearman r=0.360, P<0.001) and increment of insulin secretion (r=0.377, P<0.001) as variables positively associated to ΔCP/GCr. A negative association to ΔCP/GCr was cold ischemia time (r=-0.330, P<0.001). A linear, backward-selection multiple regression was used to obtain a model for the transplanted functional islet mass (TFIM). The TFIM model, composed of islet volume transplanted, increment of insulin secretion, cold ischemia time, and exocrine tissue volume transplanted, accounted for 43% of the variance of the clinical outcome in the islet-after-kidney data set.. The TFIM provides a straightforward and potent tool to guide the decision to use a specific islet preparation for clinical transplantation. Topics: Adult; Age Factors; Aged; Blood Glucose; C-Peptide; Cells, Cultured; Cold Ischemia; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Graft Survival; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Models, Biological; Organ Size; Quality Control; Retrospective Studies; Tissue Donors; Transplantation; Treatment Outcome | 2012 |
Epidermal growth factor and gastrin on PDX1 expression in experimental type 1 diabetic rats.
The aim of this study was to investigate whether combined epidermal growth factor (EGF) and gastrin can correct the hyperglycemia induced by streptozotocin (STZ) in rats and to determine the involvement of the transcription factor pancreatic and duodenal homeobox 1 (PDX1) in this process.. Rat diabetes was induced by intraperitoneal injection of STZ. The mRNA and protein levels of insulin and PDX1 were determined by real-time reverse transcriptase polymerase chain reaction and immunohistochemistry. Serum levels of C-peptide and insulin were analyzed using radioimmunoassay kits.. The combined administration of EGF and gastrin efficiently reversed the hyperglycemia induced by STZ. Elevated insulin concentration was detected in diabetic rats treated with EGF plus gastrin. The authors also found that both insulin and PDX1 expression were reduced in STZ-treated rats. Interestingly, the combination treatment also significantly enhanced the mRNA levels of insulin and PDX1, and that of their protein products.. Therapy with EGF plus gastrin corrected hyperglycemia and maintained insulin content in STZ-induced diabetic rats via up-regulation of PDX1 expression, suggesting that this combination treatment may provide a valuable approach for pancreatic islet neogenesis in vivo. Topics: Animals; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Drug Combinations; Epidermal Growth Factor; Gastrins; Homeodomain Proteins; Humans; Hyperglycemia; Injections, Subcutaneous; Insulin; Islets of Langerhans; Male; Radioimmunoassay; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trans-Activators | 2012 |
Time dynamics of autoantibodies are coupled to phenotypes and add to the heterogeneity of autoimmune diabetes in adults: the HUNT study, Norway.
The aetiology of latent autoimmune diabetes in adults (LADA), assessed by autoimmune markers, is insufficiently clarified. We cross-sectionally investigated the prevalence and prospectively the prediabetic and postdiabetic presence of antibodies to glutamic acid decarboxylase (GADA), insulinoma-associated protein 2 and zinc transporter 8 in LADA and in type 1 diabetes.. We included 208 'classic' type 1, 161 LADA and 302 type 2 diabetic cases from the second (HUNT2: 1995–1997) and third (HUNT3: 2006–2008) Nord-Trøndelag health surveys. Prospective data were available for 59 type 1, 44 LADA and 302 type 2 diabetic cases followed from HUNT2 to HUNT3. From HUNT3, 24 type 1 diabetic and 31 LADA incident cases were available.. Cross-sectionally, 90% of LADA cases were positive for only one antibody (10% multiple-antibodypositive). Prospectively, 59% of GADA-positive LADA patients in HUNT2 were no longer positive in HUNT3. LADA patients who became negative possessed less frequently risk HLA haplotypes and were phenotypically more akin to those with type 2 diabetes than to those who stayed positive. Still, those losing positivity differed from those with type 2 diabetes by lower C-peptide levels (p = 0.009). Of incident LADA cases in HUNT3, 64% were already antibody-positive in HUNT2, i.e. before diabetes diagnosis. These incident LADA cases were phenotypically more akin to type 1 diabetes than were those who did not display positivity in HUNT2.. The pattern of antibodies, the postdiabetic loss or persistence as well as the prediabetic absence or presence of antibodies influence LADA phenotypes. Time-dependent presence or absence of antibodies adds new modalities to the heterogeneity of LADA. Topics: Adult; Aged; Autoantibodies; C-Peptide; Cation Transport Proteins; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Haplotypes; HLA Antigens; Humans; Male; Middle Aged; Norway; Prediabetic State; Prevalence; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Risk; Zinc Transporter 8 | 2012 |
Early metabolic markers that anticipate loss of insulin independence in type 1 diabetic islet allograft recipients.
The objective of this study was to identify predictors of insulin independence and to establish the best clinical tools to follow patients after pancreatic islet transplantation (PIT). Sequential metabolic responses to intravenous (I.V.) glucose (I.V. glucose tolerance test [IVGTT]), arginine and glucose-potentiated arginine (glucose-potentiated arginine-induced insulin secretion [GPAIS]) were obtained from 30 patients. We determined the correlation between transplanted islet mass and islet engraftment and tested the ability of each assay to predict return to exogenous insulin therapy. We found transplanted islet mass within an average of 16 709 islet equivalents per kg body weight (IEQ/kg BW; range between 6602 and 29 614 IEQ/kg BW) to be a poor predictor of insulin independence at 1 year, having a poor correlation between transplanted islet mass and islet engraftment. Acute insulin response to IVGTT (AIR(GLU) ) and GPAIS (AIR(max) ) were the most accurate methods to determine suboptimal islet mass engraftment. AIR(GLU) performed 3 months after transplant also proved to be a robust early metabolic marker to predict return to insulin therapy and its value was positively correlated with duration of insulin independence. In conclusion, AIR(GLU) is an early metabolic assay capable of anticipating loss of insulin independence at 1 year in T1D patients undergoing PIT and constitutes a valuable, simple and reliable method to follow patients after transplant. Topics: Adolescent; Adult; Aged; Biomarkers; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Graft Rejection; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Postoperative Complications; Transplantation, Homologous; Young Adult | 2012 |
Potential correlation between plasma total GIP levels and body mass index in Japanese patients with types 1 or 2 diabetes mellitus.
Glucose-dependent insulinotropic polypeptide (GIP) secretion in diabetic Europeans with type 1 (T1DM) and type 2 (T2DM) following test meal (TM) has been shown to be normal. In Japanese patients with T2DM, GIP secretion was also normal. We determined whether GIP secretin is influenced by various factors. Plasma glucose (PG), serum insulin (s-IRI), serum C-peptide (s-CPR), and plasma total GIP (p-total GIP) levels were measured at 0, 30, and 60 minutes after TM (560 kcal) in patients with T1DM (n = 15, group 1) and T2DM (n = 29, group 2) treated with various medications. HbA1c was also measured. At baseline, means of age, BMI, HbA1c, PG, s-CPR, SUIT (secretory unit in transplantation) and p-total GIP were significantly lower in group 1 than in group 2. Each mean of postprandial p-total GIP levels after TM in all patients was more dramatically increased than other factors. The area under the curve (AUC) of p-total GIP levels in early-phase (0 to 30 min) was significantly positively correlated with BMI in group 2 but not in group 1, and not with other factors. These results indicate that the GIP secretion after TM in diabetic Japanese patients was dramatically increased, and the AUC of GIP secretion in early-phase was positively correlated with BMI in non-obese and obese patients with T2DM, but not with T1DM. The increase was not influenced by gender, age, glycemic control, duration of disease, micro- or macro-vascular disturbances, or oral drugs. Topics: Asian People; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gastric Inhibitory Polypeptide; Glycated Hemoglobin; Humans; Insulin; Male; Middle Aged; Obesity; Postprandial Period | 2012 |
The lack of long-range negative correlations in glucose dynamics is associated with worse glucose control in patients with diabetes mellitus.
Glucose dynamics measured in ambulatory settings are fluid in nature and exhibit substantial complexity. We recently showed that a long-range negative correlation of glucose dynamics, which is considered to reflect blood glucose controllability over a substantial period, is absent in patients with diabetes mellitus. This was demonstrated using detrended fluctuation analysis (DFA), a modified random-walk analysis method for the detection of long-range correlations. In the present study, we further assessed the relationships between the established clinical indices of glycemic or insulinogenic control of hemoglobin A(1c) (HbA(1c)), glycated albumin (GA), 1,5-anhydroglucitol, and urine C-peptide immunoreactivity and the recently proposed DFA-based indices obtained from continuous glucose monitoring in 104 Japanese diabetic patients. Significant correlations between the following parameters were observed: (1) HbA(1c) and the long-range scaling exponent α(2) (r = 0.236, P < .05), (2) GA and α(2) (r = 0.254, P < .05), (3) GA and the short-range scaling exponent α(1) (r = 0.233, P < .05), and (4) urine C-peptide immunoreactivity and the mean glucose fluctuations (r = -0.294, P < .01). Therefore, we concluded that increases in the long-range DFA scaling exponent, which are indicative of the lack of a long-range negative correlation in glucose dynamics, reflected abnormalities in average glycemic control as clinically determined using HbA(1c) and GA parameters. Topics: Adult; Blood Glucose; C-Peptide; Deoxyglucose; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Glycated Serum Albumin; Glycation End Products, Advanced; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Serum Albumin | 2012 |
Reversal of diabetes through gene therapy of diabetic rats by hepatic insulin expression via lentiviral transduction.
Due to shortage of donor tissue a cure for type 1 diabetes by pancreas organ or islet transplantation is an option only for very few patients. Gene therapy is an alternative approach to cure the disease. Insulin generation in non-endocrine cells through genetic engineering is a promising therapeutic concept to achieve insulin independence in patients with diabetes. In the present study furin-cleavable human insulin was expressed in the liver of autoimmune-diabetic IDDM rats (LEW.1AR1/Ztm-iddm) and streptozotocin-diabetic rats after portal vein injection of INS-lentivirus. Within 5-7 days after the virus injection of 7 × 10(9) INS-lentiviral particles the blood glucose concentrations were normalized in the treated animals. This glucose lowering effect remained stable for the 1 year observation period. Human C-peptide as a marker for hepatic release of human insulin was in the range of 50-100 pmol/ml serum. Immunofluorescence staining of liver tissue was positive for insulin showing no signs of transdifferentiation into pancreatic β-cells. This study shows that the diabetic state can be efficiently reversed by insulin release from non-endocrine cells through a somatic gene therapy approach. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Genetic Therapy; Genetic Vectors; Humans; Injections, Intravenous; Insulin; Lentivirus; Liver; Male; Portal Vein; Rats; Rats, Transgenic; Streptozocin | 2012 |
Dead or alive?
Topics: Biological Assay; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Male | 2012 |
Persistence of prolonged C-peptide production in type 1 diabetes as measured with an ultrasensitive C-peptide assay.
To examine persistence of C-peptide production by ultrasensitive assay years after onset of type 1 diabetes and factors associated with preserving β-cell function.. Serum C-peptide levels, a marker of insulin production and surviving β-cells, were measured in human subjects (n = 182) by ultrasensitive assay, as was β-cell functioning. Twenty-two times more sensitive than standard assays, this assay's lower detection limit is 1.5 pmol/L. Disease duration, age at onset, age, sex, and autoantibody titers were analyzed by regression analysis to determine their relationship to C-peptide production. Another group of four patients was serially studied for up to 20 weeks to examine C-peptide levels and functioning.. The ultrasensitive assay detected C-peptide in 10% of individuals 31-40 years after disease onset and with percentages higher at shorter duration. Levels as low as 2.8 ± 1.1 pmol/L responded to hyperglycemia with increased C-peptide production, indicating residual β-cell functioning. Several other analyses showed that β-cells, whose C-peptide production was formerly undetectable, were capable of functioning. Multivariate analysis found disease duration (β = -2.721; P = 0.005) and level of zinc transporter 8 autoantibodies (β = 0.127; P = 0.015) significantly associated with C-peptide production. Unexpectedly, onset at >40 years of age was associated with low C-peptide production, despite short disease duration.. The ultrasensitive assay revealed that C-peptide production persists for decades after disease onset and remains functionally responsive. These findings suggest that patients with advanced disease, whose β-cell function was thought to have long ceased, may benefit from interventions to preserve β-cell function or to prevent complications. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biological Assay; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Male; Middle Aged; Reproducibility of Results; Young Adult | 2012 |
Insulinoma may mask the existence of Type 1 diabetes.
Insulinoma is a tumour of insulin-producing cells of the pancreas and is known to be one of the causes of hypoglycaemia. Usually, appropriate removal of the insulinoma results in normalization of blood glucose levels. However, we found novel cases of insulinoma, in which hyperglycaemia developed soon after resection of the insulinoma.. We encountered two patients with repeated hypoglycaemia caused by insulinoma. Following removal of the insulinoma, unanticipated hyperglycaemia was observed in both patients. Thereafter, their blood tests revealed low levels of serum C-peptide and high titres of anti-glutamic acid decarboxylase antibody, indicating concomitant Type 1 diabetes. Indeed, histological examination of the resected specimen revealed that one patient showed insulitis in non-tumorous pancreatic tissue in which β-cells had already disappeared. Moreover, inflammatory cells infiltrated the insulinoma, as if it were insulitis of Type 1 diabetes, suggesting the existence of anti-islet autoimmunity.. These are first cases of insulinoma associated with underlying Type 1 diabetes. Physicians should be aware of the possibility that insulinoma may mask Type 1 diabetes, and measurement of anti-islet autoantibodies may be helpful to find underlying Type 1 diabetes, such as in these cases. It is pathologically interesting that the immune cell infiltration into insulinoma may be suggestive of anti-islet autoimmunity. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diagnosis, Differential; Female; Humans; Hyperglycemia; Insulinoma; Islets of Langerhans; Male; Pancreatic Neoplasms | 2012 |
Fulminant Type 1 diabetes in a pregnant woman as an initial manifestation of the insulin autoimmune syndrome.
Fulminant Type 1 diabetes is a subtype of Type 1 diabetes characterized by (1) abrupt onset of diabetes, (2) very short duration of hyperglycaemia with mildly elevated HbA(1c) (< 69 mmol/mol, 8.5%), (3) rapid progression to diabetic ketoacidosis, (4) very low C-peptide level, and (5) often associated with elevated serum pancreatic enzymes, and absence of diabetes-related autoantibodies. We encountered a case of fulminant Type 1 diabetes that developed with an initial manifestation of the insulin autoimmune syndrome and rapidly progressed to diabetic ketoacidosis during pregnancy. A 31-year-old Korean woman presented with recurrent sudden onset of sweating and change of consciousness during sleep at 19 weeks gestation. During a 72-h fasting test, hypoglycaemia (1.72 mmol/l) occurred at 4 h after the start of the test. At that time, there was a high insulin level (370.2 μU/ml), a paradoxically low C-peptide level (0.01 nmol/l) and a positive insulin autoantibody test. An oral glucose tolerance test revealed postprandial hyperglycaemia. She was initially diagnosed as the insulin autoimmune syndrome. On the day 5 of admission, she developed diabetic ketoacidosis. Her HbA(1c) was 62 mmol/mol (7.8%). The rapid progression of diabetic ketoacidosis altered the diagnosis to fulminant Type 1 diabetes. This case differed from typical fulminant Type 1 diabetes because it presented with hypoglycaemia, and positive insulin and anti-phospholipid antibody tests. Her HLA typing was HLA-DQA1*0302, 0501, HLA-DRB1*0301 (DR3), 0901(DR9). Her glucose level was subsequently very well controlled with multiple insulin injections and she successfully delivered a healthy baby. Topics: Adult; Antibodies, Antiphospholipid; Autoantibodies; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Progression; Female; Glucose Tolerance Test; Glycated Hemoglobin; HLA-DQ alpha-Chains; HLA-DRB1 Chains; Humans; Hypoglycemic Agents; Infant, Newborn; Insulin; Pregnancy; Pregnancy in Diabetics; Pregnancy Outcome; Syndrome | 2012 |
The impact of insulin administration during the mixed meal tolerance test.
The mixed meal tolerance test is the gold standard measure of endogenous insulin secretion. Practical issues limit the routine clinical use of this test, including omitting insulin prior to the ingestion of a high-carbohydrate liquid mixed meal, which can result in marked hyperglycaemia. We aimed to assess whether insulin omission is necessary during the mixed meal tolerance test and whether fasting C-peptide was a practical alternative to the test.. Ninety-one adults with insulin-treated diabetes (Type 1 n = 56, Type 2 n = 35) underwent two mixed meal tolerance tests; one standard without insulin and one with the patient's usual morning insulin.. The 90-min serum C-peptide was highly correlated in the standard mixed meal tolerance test and the test with insulin (r = 0.98, P < 0.0001). There was a 20% reduction in the peak C-peptide value when insulin was given {test with insulin [0.39 (0.01-1.16) vs. test without insulin 0.48 (0.01-1.36) nmol/l, P = 0.001]}, but the original serum C-peptide cut-off for significant endogenous insulin secretion (≥ 0.2 nmol/l) still correctly classified 90/91 patients (98% sensitivity/100% specificity). Fasting serum C-peptide was highly correlated to 90-min serum C-peptide during the test (r = 0.97, P < 0.0001). A fasting serum C-peptide ≥ 0.07 nmol/l was the optimal cut-off (100% sensitivity and 97% specificity) for significant endogenous insulin secretion (defined as 90-min stimulated serum C-peptide ≥ 0.2 nmol/l).. Insulin omission may not always be necessary during a mixed meal tolerance test and fasting serum C-peptide may offer a practical alternative in insulin-treated patients. Topics: Adolescent; Adult; Age of Onset; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; England; Fasting; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin Secretion; Male; Meals; Middle Aged; Young Adult | 2012 |
Human insulin secreted from insulinogenic xenograft restores normoglycemia in type 1 diabetic mice without immunosuppression.
In the present study, we examined the therapeutic potential of human amnion-derived insulin-secreting cells for type 1 diabetes. Human amniotic mesenchymal stem cells (hAMs) were isolated from amnion and cultivated to differentiate into insulin-secreting cells in vitro. After culture in vitro, the differentiated cells (hAM-ISCs) were intensively stained with dithizone and secreted insulin and c-peptide in a high-glucose-dependent manner. They expressed mRNAs of pancreatic cell-related genes, including INS, PDX1, Nkx6-1, NEUROG3, ISL1, NEUROD1, GLUT1, GLUT2, PC1/3, PC2, GCK, PPY, SST, and GC, and were positive for human insulin and c-peptide. Transplantation of hAM-ISCs into the kidneys of mice with streptozotocin-induced diabetes restored body weight and normalized the blood glucose levels, which lasted for 210 days. Only human insulin and c-peptide were detected in the blood of normalized mice after 2 months of transplantation, but little mouse insulin and c-peptide. Removal of graft-bearing kidneys from these mice resulted in causing hyperglycemia again. Human cell-specific gene, hAlu, and human pancreatic cell-specific genes, insulin, PDX1, GLUT1, GLP1R, Nkx6-1, NEUROD1, and NEUROG3, were detected in the graft-bearing kidneys. Colocalization of human insulin and human nuclei antigen was also observed. These results demonstrate that hAMs could differentiate into functional insulin-secreting cells in vitro, and human insulin secreted from hAM-ISCs following transplantation into type 1 diabetic mice could normalize hyperglycemia, overcoming immune rejection for a long period. Topics: Animals; Blood Glucose; C-Peptide; Cell Differentiation; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Female; Humans; Hyperglycemia; Immunohistochemistry; Insulin; Insulin Secretion; Insulin-Secreting Cells; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Transplantation, Heterologous | 2012 |
Beyond HLA-A*0201: new HLA-transgenic nonobese diabetic mouse models of type 1 diabetes identify the insulin C-peptide as a rich source of CD8+ T cell epitopes.
Type 1 diabetes is an autoimmune disease characterized by T cell responses to β cell Ags, including insulin. Investigations employing the NOD mouse model of the disease have revealed an essential role for β cell-specific CD8(+) T cells in the pathogenic process. As CD8(+) T cells specific for β cell Ags are also present in patients, these reactivities have the potential to serve as therapeutic targets or markers for autoimmune activity. NOD mice transgenic for human class I MHC molecules have previously been employed to identify T cell epitopes having important relevance to the human disease. However, most studies have focused exclusively on HLA-A*0201. To broaden the reach of epitope-based monitoring and therapeutic strategies, we have looked beyond this allele and developed NOD mice expressing human β(2)-microglobulin and HLA-A*1101 or HLA-B*0702, which are representative members of the A3 and B7 HLA supertypes, respectively. We have used islet-infiltrating T cells spontaneously arising in these strains to identify β cell peptides recognized in the context of the transgenic HLA molecules. This work has identified the insulin C-peptide as an abundant source of CD8(+) T cell epitopes. Responses to these epitopes should be of considerable utility for immune monitoring, as they cannot reflect an immune reaction to exogenously administered insulin, which lacks the C-peptide. Because the peptides bound by one supertype member were found to bind certain other members also, the epitopes identified in this study have the potential to result in therapeutic and monitoring tools applicable to large numbers of patients and at-risk individuals. Topics: Animals; C-Peptide; CD8-Positive T-Lymphocytes; Cells, Cultured; Diabetes Mellitus, Type 1; Epitopes, T-Lymphocyte; Female; Genetic Predisposition to Disease; HLA-A11 Antigen; HLA-A2 Antigen; Humans; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, Transgenic; Protein Binding | 2012 |
The application of the diabetes prevention trial-type 1 risk score for identifying a preclinical state of type 1 diabetes.
We assessed the utility of the Diabetes Prevention Trial-Type 1 Risk Score (DPTRS) for identifying individuals who are highly likely to progress to type 1 diabetes (T1D) within 2 years.. The DPTRS was previously developed from Diabetes Prevention Trial-Type 1 (DPT-1) data and was subsequently validated in the TrialNet Natural History Study (TNNHS). DPTRS components included C-peptide and glucose indexes from oral glucose tolerance testing, along with age and BMI. The cumulative incidence of T1D was determined after DPTRS thresholds were first exceeded and after the first occurrences of glucose abnormalities.. The 2-year risks after the 9.00 DPTRS threshold was exceeded were 0.88 and 0.77 in DPT-1 (n = 90) and the TNNHS (n = 69), respectively. In DPT-1, the 2-year risks were much lower after dysglycemia first occurred (0.37; n = 306) and after a 2-h glucose value between 190 and 199 mg/dL was first reached (0.64; n = 59). Among those who developed T1D in DPT-1, the 9.00 threshold was exceeded 0.81 ± 0.53 years prior to the conventional diagnosis. Postchallenge C-peptide levels were substantially higher (P = 0.001 for 30 min; P < 0.001 for other time points) when the 9.00 threshold was first exceeded compared with the levels at diagnosis.. A DPTRS threshold of 9.00 identifies individuals who are very highly likely to progress to the conventional diagnosis of T1D within 2 years and, thus, are essentially in a preclinical diabetic state. The 9.00 threshold is exceeded well before diagnosis, when stimulated C-peptide levels are substantially higher. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Incidence; Prediabetic State; Risk | 2012 |
Does glucagon stimulation test help to predict autoimmunity in newly diagnosed non obese adults with diabetes?
Classification of diabetes type in adults patients remains difficult. This study was undertaken to determine the relationship between presence of autoantibodies in the serum and the result of glucagon stimulation test in non obese patients at aged above 35 years with newly diagnosed diabetes.Study involved 52 non obese adults aged 42 years [interquartile range (IQR): 37-46], with body mass index (BMI) 23.7 kg/m2 (IQR: 21.4-26.2). Presence of autoantibodies to islet cells (ICA), antibodies to tyrosine phosphatase (IA-2), glutamic acid decarboxylase autoantibodies (anti-GAD) and plasma fasting and stimulating (6 min after intravenous injection of 1 mg glucagon) C-peptide level was assessed.73.1% subjects had at least 1 of 3 assessed autoantibodies, 26.9% patients were autoantibodies negative. According to serum C-peptide concentration after stimulation test with glucagon patients were divided into 2 groups. Receiver Operating Characteristic (ROC) Curve for determination of an optimal cut-point (C-peptide stimulation above and below 1.6) was used. In patients with negative stimulation test higher prevalence of 2 (33.3% vs. 66.7%; p=0.04) or 3 (12.5% vs. 87.5%, p=0.01) positive autoantibodies was noticed in comparison to patients with positive stimulation test. Multivariate logistic regression showed that presence of autoantibodies was independently associated with stimulated C-peptide level (OR 2.3; 95%CI: 1.07-5.28, p=0.03).Autoimmune diabetes should be suspected in subjects with lower response of β- cell in glucagon stimulation test. If the C-peptide do not increase more than 1.6 after glucagon presence of autoanibodies is more probable. Topics: Adult; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glutamate Decarboxylase; Humans; Male; Middle Aged | 2012 |
Beta cell function and BMI in ethnically diverse children with newly diagnosed autoimmune type 1 diabetes.
To examine the relationship between BMI and beta-cell function at diagnosis of autoimmune type 1 diabetes (T1D) in a large group of ethnically diverse children.. Cross-sectional analysis of 524 children (60.8% White, 19.5% Hispanic, 14.5% African-American, 5.2% other non-Hispanic; mean age = 9.8 yr [SD = 2.5]) with newly diagnosed autoimmune T1D.. As much as 22.2% of children were overweight or obese. Median random serum C-peptide was 0.40 ng/mL (25th-75th percentiles = 0.3-0.8), with median glycemia of 366 mg/dL (25th-75th percentiles = 271-505). Median C-peptide was 0.3, 0.5, 0.7, and 0.85 ng/mL, respectively, in underweight, normal weight, overweight, and obese children (p < 0.0001, Kruskal-Wallis). In the final model (p < 0.0001), the odds of having preserved C-peptide (≥0.6 ng/mL) were increased by 2.4-fold (95% CI = 1.2-4.9, p < 0.015) and 4.1-fold (1.9-8.5, p < 0.0001), respectively, in overweight and obese compared to lean children; 1.3-fold per each year of age; 2.5-fold in girls compared to boys; 4-fold in children who presented without, compared to with, diabetes ketoacidosis (DKA); and decreased by 21% for each point increase in HbA1c. Tanner stage, race/ethnicity, glycemia, and number of anti-islet antibodies expressed were not independently associated with preserved C-peptide. The association between BMI and C-peptide levels was significant in children with and without preserved C-peptide. Excluding patients who presented with DKA and/or using BMI obtained 5 wk after diagnosis did not alter the results.. Obese and overweight children compared to lean children have greater beta-cell function at the onset of autoimmune T1D. Prospective studies on the relationships among BMI, beta-cell function, and progression to clinical T1D are warranted. Topics: Autoantibodies; Black or African American; Blood Glucose; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Hispanic or Latino; Humans; Insulin-Secreting Cells; Male; Obesity; Overweight; Puberty; White People | 2012 |
Short-term subcutaneous insulin treatment delays but does not prevent diabetes in NOD mice.
Despite encouraging results in the NOD mouse, type 1 diabetes prevention trials using subcutaneous insulin have been unsuccessful. To explain these discrepancies, 3-week-old NOD mice were treated for 7 weeks with subcutaneous insulin at two different doses: a high dose (0.5 U/mouse) used in previous mouse studies; and a low dose (0.005 U/mouse) equivalent to that used in human trials. Effects on insulitis and diabetes were monitored along with immune and metabolic modifications. Low-dose insulin did not have any effect on disease incidence. High-dose treatment delayed but did not prevent diabetes, with reduced insulitis reappearing once insulin discontinued. This effect was not associated with significant immune changes in islet infiltrates, either in terms of cell composition or frequency and IFN-γ secretion of islet-reactive CD8(+) T cells recognizing the immunodominant epitopes insulin B(15-23) and islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)(206-214). Delayed diabetes and insulitis were associated with lower blood glucose and endogenous C-peptide levels, which rapidly returned to normal upon treatment discontinuation. In conclusion, high- but not low-dose prophylactic insulin treatment delays diabetes onset and is associated with metabolic changes suggestive of β-cell "rest" which do not persist beyond treatment. These findings have important implications for designing insulin-based prevention trials. Topics: Animals; Blood Glucose; C-Peptide; CD8-Positive T-Lymphocytes; Diabetes Mellitus, Type 1; Hypoglycemic Agents; Injections, Subcutaneous; Insulin; Interferon-gamma; Mice; Mice, Inbred NOD | 2012 |
Low frequency of regulatory T cells in the peripheral blood of children with type 1 diabetes diagnosed under the age of five.
The highest annual increase in the incidence of type 1 diabetes (T1D) in children under the age of 5 years and aggressive process of β-cell destruction in this age group indicate the need to assess the immune system. The aim of this study was to evaluate regulatory T cells (Tregs) frequency in the peripheral blood of children <5 years of age with newly diagnosed T1D in comparison with diabetic children diagnosed at a later age and healthy controls. 40 children with newly diagnosed T1D (20 children <5 years of age and 20 older patients) and 40 age-matched controls were included in this study. Flow cytometric analysis of Tregs was performed using the following markers: CD4, CD25, CD127, FoxP3, IL-10, and TGF-β. Apoptosis was measured using anti-active caspase 3 monoclonal antibody. Fasting C-peptide and HbA1c were monitored as well. We showed that T1D children <5 years had lower C-peptide concentration than diabetic children ≥5 years of age (0.32 vs. 0.80 ng/ml, respectively, p = 0.0005). There was lower frequency of CD4(+)CD25(high)CD127(low)FoxP3(+) Tregs in T1D children <5 years than ≥5 years of age (0.87 vs. 1.56 %, respectively, p = 0.017). Diabetic children <5 years had lower CD4(+)CD25(high)CD127(low)FoxP3(+), CD4(+)CD25(high)IL-10, and CD4(+)CD25(high)TGF-β Tregs compared to age-matched controls. There was no difference in Tregs apoptosis between the examined groups. This study highlights the distinctiveness of diabetes in children <5 years of age. Understanding the differences of immune system activity in the young diabetic children would open the way to identify children at risk for T1D and enables the use of novel forms of intervention. Topics: Adolescent; Antigens, CD; C-Peptide; Cell Separation; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Flow Cytometry; Forkhead Transcription Factors; Glycated Hemoglobin; Humans; Infant; Interleukin-10; Male; T-Lymphocytes, Regulatory; Transforming Growth Factor beta | 2012 |
Association between autoantibodies to the Arginine variant of the Zinc transporter 8 (ZnT8) and stimulated C-peptide levels in Danish children and adolescents with newly diagnosed type 1 diabetes.
The zinc transporter 8 (ZnT8) was recently identified as a common autoantigen in type 1 diabetes (T1D) and inclusion of ZnT8 autoantibodies (ZnT8Ab) was found to increase the diagnostic specificity of T1D.. The main aims were to determine whether ZnT8Ab vary during follow-up 1 year after diagnosis, and to relate the reactivity of three types of ZnT8Ab to the residual stimulated C-peptide levels during the first year after diagnosis.. A total of 129 newly diagnosed T1D patients <15 years was followed prospectively 1, 3, 6, and 12 months after diagnosis.. Hemoglobin A1c, meal-stimulated C-peptide, ZnT8Ab, and other pancreatic autoantibodies were measured at each visit. Patients were genotyped for the rs13266634 variant at the SLC30A8 gene and HLA-DQ alleles.. The levels of all ZnT8Ab [ZnT8Arg (arginine), ZnT8Trp (tryptophan), ZnT8Gln (glutamine)] tended to decrease during disease progression. A twofold higher level of ZnT8Arg and ZnT8Gln was associated with 4.6%/5.2% (p = 0.02), 5.3%/8.2% (p = 0.02) and 8.9%/9.7% (p = 0.004) higher concentrations of stimulated C-peptide 3, 6, and 12 months after diagnosis. The TT genotype carriers of the SLC30A8 gene had 45.8% (p = 0.01) and 60.1% (p = 0.002) lower stimulated C-peptide 6 and 12 months after diagnosis compared to the CC and the CT genotype carriers in a recessive model.. The levels of the Arg variant of the ZnT8 autoantibodies are associated with higher levels of stimulated C-peptide after diagnosis of T1D and during follow-up. Carriers of the TT genotype of the SLC30A8 gene predict lower stimulated C-peptide levels 12 months after diagnosis. Topics: Adolescent; Age Factors; Amino Acid Substitution; Arginine; Autoantibodies; C-Peptide; Cation Transport Proteins; Child; Child, Preschool; Denmark; Diabetes Mellitus, Type 1; Female; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Humans; Infant; Male; Mutant Proteins; Up-Regulation; Zinc Transporter 8 | 2012 |
Fall in C-peptide during first 2 years from diagnosis: evidence of at least two distinct phases from composite Type 1 Diabetes TrialNet data.
Interpretation of clinical trials to alter the decline in β-cell function after diagnosis of type 1 diabetes depends on a robust understanding of the natural history of disease. Combining data from the Type 1 Diabetes TrialNet studies, we describe the natural history of β-cell function from shortly after diagnosis through 2 years post study randomization, assess the degree of variability between patients, and investigate factors that may be related to C-peptide preservation or loss. We found that 93% of individuals have detectable C-peptide 2 years from diagnosis. In 11% of subjects, there was no significant fall from baseline by 2 years. There was a biphasic decline in C-peptide; the C-peptide slope was -0.0245 pmol/mL/month (95% CI -0.0271 to -0.0215) through the first 12 months and -0.0079 (-0.0113 to -0.0050) from 12 to 24 months (P < 0.001). This pattern of fall in C-peptide over time has implications for understanding trial results in which effects of therapy are most pronounced early and raises the possibility that there are time-dependent differences in pathophysiology. The robust data on the C-peptide obtained under clinical trial conditions should be used in planning and interpretation of clinical trials. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Insulin-Secreting Cells; Middle Aged; Randomized Controlled Trials as Topic | 2012 |
Hypoglycemia after simultaneous pancreas-kidney transplant: fact or factitious?
Topics: Adult; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Factitious Disorders; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Kidney Transplantation; Pancreas Transplantation; Predictive Value of Tests; Recurrence; Self Medication; Treatment Outcome | 2012 |
Plasma C-peptide concentration in women with Type 1 diabetes during early and late pregnancy.
There are previous suggestions of increased C-peptide concentration in women with Type 1 diabetes during pregnancy. Our aim was to re-evaluate the hypothesis of a pregnancy-induced increase by measuring plasma C-peptide concentration in women with stable blood glucose control under standardized fasting and meal-stimulated conditions.. Ten women with Type 1 diabetes; median age 31.1 years, median diabetes duration 19 years, median HbA(1c) 52 mmol/mol (6.9%) were admitted to a clinical research facility for two 24-h visits in early (12-16 weeks) and late (28-32 weeks) pregnancy. Women They ate standardized study meals - 80-g carbohydrate dinner, 60-g carbohydrate breakfast, and fasted between meals and overnight. Closed-loop insulin delivery maintained stable and comparable glycaemic conditions. Paired samples for plasma glucose and C-peptide were obtained.. Plasma glucose levels were comparable in early (median 6.5 mmol/l; interquartile range 5.6-8.6) and late pregnancy (median 7.0 mmol/l; interquartile range 6.1-7.8; P = 0.72). There was no change in fasting or meal-stimulated plasma C-peptide concentration from early to late pregnancy; mean difference 4.0 pmol/l (95% CI -6.0 to 7.0; P = 0.9). Four women had detectable C-peptide; peak (range) early vs. late pregnancy 48.5 (10-115) vs. 40.0 pmol/l (80-105); P = 0.5, which was weakly associated with plasma glucose; R(2) = 0.15, P < 0.0001.. We found no gestational changes in plasma C-peptide concentration. Previously reported increases may reflect differences in glucose control and/or exogenous insulin doses. This study highlights the importance and challenges of standardizing experimental conditions for accurate plasma C-peptide measurement during Type 1 diabetes pregnancy. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Meals; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, First; Pregnancy Trimester, Third | 2012 |
Case of type 1 diabetes mellitus following interferon β-1a treatment for multiple sclerosis.
A 57-year-old woman who had been treated with interferon β-1a (IFNβ-1a) for multiple sclerosis was diagnosed with diabetic ketosis. Her fasting serum C-peptide (F-CPR) was 1.9 ng/mL and her daily urinary C-peptide (U-CPR) was 24.1 µg/day. Her anti-glutamic acid decarboxylase (GAD) antibody was 3.5 U/mL. Seven months later, she was hospitalized with body weight loss and a high level of hemoglobin A1c [11.1% (JDS)]. Her F-CPR and U-CPR were very low (0.1 ng/mL and 8.35 µg/day, respectively), and anti-GAD antibody became distinctly positive (12.4 U/mL). She had HLA-DRB1*04:05, A24, and B54. For these reasons, IFNβ-1a administration was considered a possible cause of type 1 diabetes mellitus in this case. Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; HLA Antigens; Humans; Interferon beta-1a; Interferon-beta; Middle Aged; Multiple Sclerosis, Relapsing-Remitting | 2012 |
Pancreatic volume is reduced in adult patients with recently diagnosed type 1 diabetes.
Pancreatic atrophy is common in longstanding type 1 diabetes, but there are limited data concerning pancreas size at diagnosis.. Our objective was to determine whether pancreatic size was reduced in patients with recently diagnosed type 1 diabetes and assess whether pancreatic volume was related to residual β-cell function or islet autoantibodies.. We conducted a controlled cohort study with strict inclusion criteria, recruiting from hospital diabetes clinics between 2007 and 2010. PATIENTS AND HEALTHY CONTROLS: Participants included 20 male adult patients (median age 27 yr) with recent-onset type 1 diabetes (median duration 3.8 months) and 24 male healthy controls (median age 27 yr).. Interventions included noninvasive magnetic resonance imaging, collection of fasting blood samples, and glucagon stimulation testing in patients.. We compared pancreatic volume estimates between patients with recent-onset type 1 diabetes and healthy controls as planned a priori.. Scans were analyzed by an experienced radiologist blinded to diabetes status. Pancreatic volume correlated with body weight in patients and controls (P = 0.007). After adjustment for body weight, mean pancreatic volume index was 26% less in patients (1.19 ml/kg, se 0.07 ml/kg) than in controls (1.61 ml/kg, se 0.08 ml/kg) (P = 0.001). No correlation was seen between pancreatic volume index in patients and diabetes duration, glucose or C-peptide levels, glycated hemoglobin, and islet autoantibodies.. Pancreatic volume is reduced by 26% in patients with type 1 diabetes within months of diagnosis, suggesting that atrophy begins years before the onset of clinical disease. Pancreatic atrophy within individuals is therefore a potential clinical marker of disease progression. Topics: Adolescent; Adult; Atrophy; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Disease Progression; Humans; Insulin; Magnetic Resonance Imaging; Male; Organ Size; Pancreas | 2012 |
[Obesity and risk factors for metabolic syndrome in young people with type 1 diabetes].
Changes in the clinical presentation of diabetes mellitus in childhood and adolescence associated with obesity have resulted in an overlap of the two most common types of diabetes with a greater clinical heterogeneity. In order to characterize the type of diabetes at onset and assess the effect of obesity, 50 children with diabetes were studied. The patients were divided into two groups according to their nutritional status at diagnosis (over-weight/obese vs. normal weight). Insulin reserve was evaluated by measuring basal C-peptide and stimulated C-peptide in response to a mixed meal (MMTT) as well as HLA-DQB1 genotype, antibodies, and family history of risk factors for metabolic disease. Of all 50 patients, 38% was overweight/obese, 84% had a positive family history of metabolic syndrome, 82% had positive antibodies, and 100% were positive for the high-risk HLA-DQB1 genotype. No significant differences were found in fasting C-peptide or glycemic index/C-peptide levels between the two groups. In the overweight/obese group C-peptide response to MMTT showed higher levels at 60 and 120 minutes (p = 0.02 and 0.03) and the area under the curve for C-peptide was also higher (1.77 ng / ml vs. 5.5 ng/ ml, p = 0.0007) than in the normal-weight group. In conclusion, overweight/obese patients with type 1A diabetes had a greater pancreatic reserve, suggesting that nutritional status may accelerate disease onset. Topics: Adolescent; Autoimmunity; Biomarkers; C-Peptide; Chi-Square Distribution; Child; Diabetes Mellitus, Type 1; Female; Genotype; Glutamate Decarboxylase; HLA-DQ beta-Chains; Humans; Insulin Antibodies; Male; Metabolic Syndrome; Obesity; Prospective Studies; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Risk Factors | 2012 |
Insulin independence after conversion from tacrolimus to cyclosporine in islet transplantation.
Topics: Area Under Curve; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Female; Humans; Hyperglycemia; Hypoglycemia; Immune Tolerance; Immunosuppressive Agents; Islets of Langerhans; Islets of Langerhans Transplantation; Middle Aged; Tacrolimus | 2012 |
Prevalence of zinc transporter 8 antibodies in gestational diabetes mellitus.
Gestational diabetes mellitus affects approximately 7% of all pregnant women. Some of these women develop autoantibodies that are generally characteristic of Type 1 diabetes. Autoantibodies targeting glutamic acid decarboxylase and tyrosine phosphatase-like protein are the most frequently reported. A recently identified autoantigen in Type 1 diabetes is zinc transporter 8. Some reports suggest that the frequency of zinc transporter 8 antibodies is as high as glutamic acid decarboxylase antibodies in Type 1 diabetes and thus a good diagnostic marker for autoimmune diabetes. There are currently no reports of zinc transporter 8 antibodies in gestational diabetes. The aim of this pilot study was to investigate the frequency of zinc transporter 8 antibodies in patients at clinical onset of gestational diabetes mellitus.. Subjects included in this pilot study were all diagnosed with gestational diabetes at Skåne University Hospital, Lund, Sweden, 2009-2010 (n = 193). Sera samples were analysed for antibodies using a commercial enzyme-linked immunosorbent assay according to the manufacturers' instructions.. We found that 19/193 patients with gestational diabetes, diagnosed in 2009-2010, were positive for at least one autoantibody. Glutamic acid decarboxylase was the most common single autoantibody (52.6%; 10/19), followed by zinc transporter 8 (21.1%; 4/19) and tyrosine phosphatase-like protein (15.8%; 3/19). Combinations of two or more antibodies were rare (10.5%; 2/19).. In this study, we found that zinc transporter 8 added 2.1% (4/193) of autoantibody positivity in women with gestational diabetes who were negative for glutamic acid decarboxylase and tyrosine phosphatase-like protein antibodies. Glutamic acid decarboxylase was still the most prevalent autoantibody in gestational diabetes, but, as zinc transporter 8 was present even in the absence of glutamic acid decarboxylase, this autoantibody could be an important independent marker of autoimmunity in gestational diabetes. Topics: Adult; Autoantibodies; C-Peptide; Cation Transport Proteins; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Glucose Tolerance Test; Glutamate Decarboxylase; Humans; Incidence; Insulin-Secreting Cells; Pilot Projects; Pregnancy; Sweden; Zinc Transporter 8 | 2012 |
Clinical evolution of beta cell function in youth with diabetes: the SEARCH for Diabetes in Youth study.
Few studies have explored the epidemiology of beta cell loss in youth with diabetes. This report describes the evolution and major determinants of beta cell function, assessed by fasting C-peptide (FCP), in the SEARCH for Diabetes in Youth study.. Participants were 1,277 youth with diabetes (948 positive for diabetes autoantibodies [DAs] and 329 negative for DAs), diagnosed when aged <20 years, who were followed from a median of 8 months post diagnosis, for approximately 30 months. We modelled the relationship between rate of change in log FCP and determinants of interest using repeated measures general linear models.. Among DA-positive youth, there was a progressive decline in beta cell function of 4% per month, independent of demographics (age, sex, race/ethnicity), genetic susceptibility to autoimmunity (HLA risk), HbA(1c) and BMI z score, or presence of insulin resistance. Among DA-negative youth, there was marked heterogeneity in beta cell loss, reflecting an aetiologically mixed group. This group likely includes youths with undetected autoimmunity (whose decline is similar to that of DA-positive youth) and youth with non-autoimmune, insulin-resistant diabetes, with limited decline (~0.7% per month).. SEARCH provides unique estimates of beta cell function decline in a large sample of youth with diabetes, indicating that autoimmunity is the major contributor. These data contribute to a better understanding of clinical evolution of beta cell function in youth with diabetes, provide strong support for the aetiological classification of diabetes type and may inform tertiary prevention efforts targeted at high-risk groups. Topics: Adolescent; Age of Onset; Autoantibodies; Biomarkers; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Fasting; Female; Glycated Hemoglobin; Humans; Insulin Resistance; Insulin-Secreting Cells; Male; Predictive Value of Tests; Risk Factors; United States | 2012 |
Transplantation of insulin-producing cells derived from umbilical cord stromal mesenchymal stem cells to treat NOD mice.
Diabetes mellitus can be treated with islet transplantation, although there is a scarcity of donors. This study investigated whether human mesenchymal stem cells (MSCs) from umbilical cord stroma could be induced to differentiate into insulin-producing cells and the effects of retro-orbital injection of human insulin-producing cells for the treatment of nonobese diabetic (NOD) mice. MSCs were isolated from human umbilical cord stroma and induced to differentiate into insulin-producing cells using differentiation medium. Differentiated cells were evaluated by immunocytochemistry, RT-PCR, and real-time PCR. C-peptide release, both spontaneous and after glucose challenge, was measured by ELISA. Insulin-producing cells were then transplanted into NOD mice. Blood glucose levels and body weights were monitored weekly. Human nuclei and C-peptide were detected in mouse livers by immunohistochemistry. Pancreatic β-cell development-related genes were expressed in the differentiated insulin-producing cells. Differentiated cells' C-peptide release in vitro increased after glucose challenge. Further, in vivo glucose tolerance tests showed that blood sugar levels decreased after the cells' transplantation into NOD mice. After transplantation, insulin-producing cells containing human C-peptide and human nuclei were located in the liver. Thus, we demonstrated that differentiated insulin-producing cells from human umbilical cord stromal MSCs transplanted into NOD mice could alleviate hyperglycemia in diabetic mice. Topics: Animals; Blood Glucose; C-Peptide; Cell Differentiation; Cell Nucleus; Cells, Cultured; Diabetes Mellitus, Type 1; Disease Models, Animal; Glucose; Humans; Insulin; Insulin-Secreting Cells; Male; Mesenchymal Stem Cells; Mice; Mice, Inbred NOD; Stromal Cells; Umbilical Cord | 2011 |
Immunological and C-peptide studies of patients with diabetes in northern Ethiopia: existence of an unusual subgroup possibly related to malnutrition.
Surveys in northern Ethiopia have demonstrated that apparent type 1 diabetes occurs more frequently than elsewhere in Africa and, indeed, in other parts of the world. We therefore investigated in detail a cohort of diabetic patients from this region to clarify the nature of this type of diabetes.. All patients attending the diabetic clinic at Mekelle Hospital in the Tigray region of northern Ethiopia were investigated over a 6 week period. Clinical, demographic and anthropometric data were collected, as well as measurements of HbA(1c), fasting lipid profile, fasting serum C-peptide and serum markers of beta cell autoimmunity, i.e. islet antigen-2 and GAD antibodies (GADA).. Of 105 patients seen, 69 (66%) were on insulin treatment and had been from or close to diagnosis. Their median age and diabetes duration were 30 and 5 years, respectively, with a male excess of 2:1. Median BMI was 20.6 kg/m². Despite these clinical characteristics suggestive of type 1 diabetes, only 42 of 69 (61%) patients were C-peptide-negative and 35% GADA-positive. Overall, 38 (36%) of the total group (n = 105) had immunological or C-peptide characteristics inconsistent with typical type 1 or type 2 diabetes. The clinical characteristics, local prevalence of undernutrition, and GADA and C-peptide heterogeneity suggest a malnutrition-related form of diabetes.. Not all patients in northern Ethiopia with apparent type 1 diabetes appear to have the form of disease seen in Europids; their disease may, in fact, be related to malnutrition. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Ethiopia; Female; Glutamate Decarboxylase; Humans; Insulin; Male; Malnutrition; Middle Aged | 2011 |
β-cell function and metabolic control in latent autoimmune diabetes in adults with early insulin versus conventional treatment: a 3-year follow-up.
The optimal treatment of latent autoimmune diabetes in adults (LADA) is not established. We explored whether early insulin treatment, which has shown beneficial effects in rodents and in human pilot studies, would result in better preservation of β-cell function or metabolic control, compared with conventional treatment.. Glucagon-stimulated C-peptide and HbAlc were evaluated at baseline and after 12, 24 and 36 months in 37 patients recently diagnosed with diabetes, aged ≥ 30 years, non-insulin-requiring and GADAb and/or ICA positive. Twenty patients received early insulin and 17 received conventional treatment (diet ± oral hypoglycaemic agents (OHA), metformin, some and/or sulfonylurea) and insulin when necessary.. Level of metabolic control, HbAlc, was preserved in the early insulin treated, while it significantly deteriorated in the conventionally treated. There was no significant difference between the groups in C-peptide after 12, 24 or 36 months, or in the decline of C-peptide. Only baseline C-peptide predicted a C-peptide of ≥ 0.5 nmol/l at 36 months. Gender, body mass index, antibody titres or HbAlc did not influence the levels of C-peptide or HbAlc at baseline or end-of-study, or the decline in C-peptide. Among the diet ± OHA-treated, 5/17 (30%) developed insulin dependency during the follow-up. No major hypoglycaemic events occurred.. Early insulin treatment in LADA leads to better preservation of metabolic control and was safe. Superior preservation of C-peptide could not be significantly demonstrated. Only baseline level of C-peptide significantly influenced C-peptide level after 3 years. Further studies exploring the best treatment in LADA are warranted. Topics: Adult; Aged; Aged, 80 and over; Analysis of Variance; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Regression Analysis; Sweden; Treatment Outcome | 2011 |
The risk factors of ketoacidosis in children with newly diagnosed type 1 diabetes mellitus.
Diabetic ketoacidosis (DKA) is still a severe complication associated with significant morbidity and mortality. The aim of this study was to determine the predictors of DKA in children with newly diagnosed type 1 diabetes mellitus (T1DM).. The study group consisted of new-onset type 1 diabetic patients admitted to our hospital between January 2006 and March 2008. One hundred and eighty-seven children were identified (95 females and 92 males) and their mean age was 8.9 ± 4.6 yr (0.8-17.8). Hemoglobin A1c, blood gases, and fasting c-peptide level were evaluated in all children. DKA was defined as a capillary pH < 7.3 and blood glucose >11 mmol/L.. At the time of T1DM diagnosis, 26% of children had DKA. Misdiagnosis was significantly associated with the incidence of DKA. In the group with DKA, c-peptide level was significantly lower than in the group without DKA (p = 0.003.) The most prone to DKA were children under 2 yr of age (n = 14). In this age group, DKA was present in 71% of individuals and the lowest c-peptide level was observed compared to older children (p < 0.0001). There was significant correlation between the c-peptide level and age of children (r = 0.41, p < 0.0001).. The incidence of DKA among newly diagnosed patients with T1DM remains unacceptably high and indicates greater necessity of medical alertness for this diagnosis, especially in the youngest children. Children under 2 yr of age remain the most prone to DKA, which may be related to delay in diagnosis and more aggressive β-cell destruction. Topics: Adolescent; Aging; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Diagnostic Errors; Female; Glycated Hemoglobin; Humans; Infant; Male; Poland; Risk Factors | 2011 |
Alleviation of hyperglycemia in diabetic rats by intraportal injection of insulin-producing cells generated from surgically resected human pancreatic tissue.
Although islet transplantation holds promise for the treatment of diabetes, the scarcity of donor tissue remains a major drawback. The aim of this study is to generate insulin-producing cells from adult human pancreatic cells isolated from surgically resected pancreatic tissue. To isolate pancreatic endocrine precursor cells from 57 surgically resected pancreases, the cells were cultured and propagated in conditioned medium after which they were differentiated in Matrigel. The resultant cells were characterized using morphology, immunofluorescent studies, expression of differentiated pancreatic islet-specific genes using quantitative reverse transcription-PCR, and glucose-induced insulin secretion through analysis of C-peptide secretion. The relationships between propagation of insulin-producing cells and clinical variables of the donor were also analyzed. Finally, insulin-producing cell function was examined in streptozotocin-induced diabetic rats. Pancreatic endocrine precursor cells were successfully cultured; insulin-producing cells cultured from soft pancreas parenchyma had a significantly higher success rate. Morphological examination revealed islet-like cluster formation upon transfer to Matrigel. The presence of the neural stem cell marker nestin, duct cell marker cytokeratin 19, and endocrine cell markers C-peptide and pancreatic and duodenal homeobox 1, was also observed. In addition, glucose-stimulated C-peptide release was significantly increased in the insulin-producing cells. Furthermore, in diabetic rats, transplantation of insulin-producing cells reduced hyperglycemia. Isolated pancreatic endocrine precursor cells from surgically resected pancreatic tissue differentiated into insulin-producing cells and showed characteristics of functional endocrine cells. Thus, surgically resected pancreatic tissue may represent an alternative source of functional insulin-producing cells. Topics: Adult; Aged; Animals; C-Peptide; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Homeodomain Proteins; Humans; Hyperglycemia; Insulin; Insulin Secretion; Insulin-Secreting Cells; Intermediate Filament Proteins; Keratin-19; Male; Middle Aged; Nerve Tissue Proteins; Nestin; Pancreas; Pancreatic Diseases; Rats; Tissue Donors; Transplantation, Heterologous; Treatment Outcome | 2011 |
Proinsulin/C-peptide ratio, glucagon and remission in new-onset Type 1 diabetes mellitus in young adults.
After initiation of treatment in Type 1 diabetes, a period with lower insulin requirement often follows, reflecting increased insulin sensitivity and improved insulin secretion. We explored if efficiency of proinsulin processing is associated with the remission phenomenon.. Seventy-eight patients with new-onset Type 1 diabetes were followed prospectively for 3 years. Daily insulin dosage, HbA(1c) , plasma glucose, proinsulin, C-peptide, glucagon concentrations and islet antibodies were determined at diagnosis and after 3, 6, 9, 12, 18, 24, 30 and 36 months. We studied remission, defined as an insulin dose ≤ 0.3 U kg(-1) 24 h(-1) and HbA(1c) within the normal range, in relation to the above-mentioned variables.. A rise and subsequent decline in plasma proinsulin and C-peptide concentrations was observed. Forty-five per cent of the patients experienced remission at one or more times, characterized by higher proinsulin and C-peptide levels, and lower proinsulin/C-peptide ratios, indicating more efficient proinsulin processing, compared with those not in remission. Non-remission also tended to be associated with higher glucagon values. Patients entering remission were more often men, had higher BMI at diagnosis, but did not differ at baseline with respect to islet antibody titres compared with patients with no remission.. Remissions after diagnosis of Type 1 diabetes were associated with lower proinsulin/C-peptide ratios, suggesting more efficient proinsulin processing, and tended to have lower glucagon release than non-remissions. This indicates that, in remission, the residual islets maintain a secretion of insulin and glucagon of benefit for control of hepatic glucose production. Topics: Adolescent; Adult; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Fasting; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin Resistance; Male; Proinsulin; Prospective Studies; Reference Values; Remission Induction; Young Adult | 2011 |
Pancreatic volume and endocrine and exocrine functions in patients with diabetes.
Exocrine function has been described in patients with diabetes. We hypothetized that patients with exocrine dysfunction have pancreatic atrophy.. This is a cohort study of hospitalized patients. Thirty-five patients were selected after detection of impaired exocrine function in routine tests, and 17 patients were matched for age and body mass index to the previous cohort. The pancreatic volume was evaluated on sections of computed tomographic scans of the pancreas. Other investigations included a glucagon stimulation test and determination of fecal elastase-1 concentration and chymotrypsin activity.. Fifty-two patients participated in this study, 24 with type 1 diabetes and 28 with type 2 diabetes. Duration of diabetes was 15 years (5-26 years; median [interquartile range]). The pancreatic volume, 42 cm (25-57 cm), was decreased in most patients. It did not differ in patients with type 1 diabetes compared with those with type 2 diabetes. It was decreased in patients treated with insulin and in those with low elastase-1 concentration or low chymotrypsin activity. In the multiple linear regression analysis, the pancreatic volume correlated with chymotrypsin activity and stimulated C-peptide.. We have unraveled a link between 2 old observations in patients with diabetes: atrophy of the pancreas and exocrine deficiency. These observations give credence to the reality of the exocrine dysfunction in patients with diabetes. Topics: Adult; Aged; Atrophy; C-Peptide; Chymotrypsin; Cohort Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Feces; Female; Glucagon; Humans; Islets of Langerhans; Male; Middle Aged; Organ Size; Pancreas; Pancreas, Exocrine; Pancreatic Elastase; Tomography, X-Ray Computed | 2011 |
Associations between periodontal disease and selected risk factors of early complications among youth with type 1 and type 2 diabetes: a pilot study.
Most studies evaluating the relation between periodontal disease and diabetes in children have not considered diabetes type.. To evaluate the relationship between periodontal damage and risk factors of diabetes complications among youth by diabetes type in a pilot study.. 155 participants (126 with type 1 diabetes; 29 with type 2 diabetes) from the SEARCH for Diabetes in Youth study in South Carolina who were <20 yr of age at diagnosis.. Cross-sectional analysis of periodontal damage (bone loss ≥3 mm on ≥1 permanent tooth site on pre-existing bitewing radiographs) and diabetes type assigned by the provider at diagnosis.. Periodontal damage was observed in 52 individuals (34%) overall, but was more common in type 2 (16/29, 55%) vs. type 1 diabetes (37/126, 29%). Among youth with type 2 diabetes, those with periodontal damage had lower fasting c-peptide (2.3 vs. 3.4 ng/mL, p-value=0.01), and higher triglyceride levels (171.8 vs. 87.2, p-value=0.01) than those without periodontal damage after adjustment for age, sex, race, education level, family income, duration of diabetes, diabetes control, time between study visit and date of radiograph, tooth brushing, and visits to the dentist. Blood pressure, waist circumference, LDL cholesterol and A1c were not associated with periodontal damage.. The associations between periodontal disease and risk factors for diabetes complications differ by diabetes type. Periodontal damage is associated with impaired beta cell function and metabolic syndrome components in type 2 but not type 1 diabetes. These findings need to be confirmed in larger, prospective studies. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Male; Metabolic Syndrome; Periodontal Diseases; Pilot Projects; Risk Factors; South Carolina; Triglycerides | 2011 |
HLA genes, islet autoantibodies and residual C-peptide at the clinical onset of type 1 diabetes mellitus and the risk of retinopathy 15 years later.
HLA genes, islet autoantibodies and residual C-peptide were studied to determine the independent association of each exposure with diabetic retinopathy (DR), 15 years after the clinical onset of type 1 diabetes in 15-34 year old individuals.. The cohort was identified in 1992 and 1993 by the Diabetes Incidence Study in Sweden (DISS), which investigates incident cases of diabetes for patients between 15 and 34 years of age. Blood samples at diagnosis were analyzed to determine HLA genotype, islet autoantibodies and serum C-peptide. In 2009, fundus photographs were obtained from patient records. Study measures were supplemented with data from the Swedish National Diabetes Registry.. The prevalence of DR was 60.2% (148/246). Autoantibodies against the 65 kD isoform of glutamate decarboxylase (GADA) at the onset of clinical diabetes increased the risk of DR 15 years later, relative risk 1.12 for each 100 WHO units/ml, [95% CI 1.02 to 1.23]. This equates to risk estimates of 1.27, [95% CI 1.04 to 1.62] and 1.43, [95% CI 1.06 to 1.94] for participants in the highest 25(th) (GADA>233 WHO units/ml) and 5(th) percentile (GADA>319 WHO units/ml) of GADA, respectively. These were adjusted for duration of diabetes, HbA(1c), treated hypertension, sex, age at diagnosis, HLA and C-peptide. Islet cell autoantibodies, insulinoma-antigen 2 autoantibodies, residual C-peptide and the type 1 diabetes associated haplotypes DQ2, DQ8 and DQ6 were not associated with DR.. Increased levels of GADA at the onset of type 1 diabetes were associated with DR 15 years later. These results, if confirmed, could provide additional insights into the pathogenesis of the most common microvascular complication of diabetes and lead to better risk stratification for both patient screenings and DR treatment trials. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Genotype; HLA Antigens; Humans; Islets of Langerhans; Male; Regression Analysis; Risk Factors; Sweden; Young Adult | 2011 |
Onset features and subsequent clinical evolution of childhood diabetes over several years.
To explore whether it is possible to predict a child's eventual diabetes phenotype using characteristics at initial presentation, we reassessed 111 young patients on average 7.8 ± 4.2 (2.2-19.7) [mean ± SD (range)] years after diagnosis.. Medical records at diagnosis for 111 patients, aged 0-17, were compared with their follow-up characteristics including stimulated C-peptide (CP) and islet autoantibodies (AB).. Initially, 18 patients were obese; 9 displayed other type 2 diabetes (T2DM) features (polycystic ovary syndrome, acanthosis, diagnosed T2DM); the remaining 84 had a classic type 1 diabetes (T1DM) presentation. At follow-up, 83 patients (75%) with no measured CP were classified as T1DM; 17 (15%) were CP+ and AB- and thus considered T2DM. Eleven patients with both T1DM and T2DM features were classified as having mixed diabetes phenotype (MDM). One-fifth (22 subjects) changed presumed phenotype at follow-up. In multivariable models, T1DM patients were younger at diagnosis, had higher initial glucose values, were more likely to have experienced ketoacidosis, and less likely to be obese or of African American ethnicity.. Ten percent of subjects had MDM and 15% had T2DM at ∼8 years' duration. Although no onset feature was completely reliable, ketoacidosis and hyperglycemia were more likely to predict T1DM; obesity and African American ethnicity made T2DM more likely. At diagnosis, features of T2DM in addition to obesity were strongly predictive of eventual T2DM phenotype. Given the significant percentage who changed or had mixed phenotype, careful tracking of all young people with diabetes is essential to correctly determine eventual disease type. Topics: Adolescent; Adult; Autoantibodies; Black or African American; C-Peptide; Chicago; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Insulin-Secreting Cells; Longitudinal Studies; Male; Obesity; Phenotype | 2011 |
The PTPN22 C1858T gene variant is associated with proinsulin in new-onset type 1 diabetes.
The protein tyrosine phosphatase nonreceptor type 2 (PTPN22) has been established as a type 1 diabetes susceptibility gene. A recent study found the C1858T variant of this gene to be associated with lower residual fasting C-peptide levels and poorer glycemic control in patients with type 1 diabetes. We investigated the association of the C1858T variant with residual beta-cell function (as assessed by stimulated C-peptide, proinsulin and insulin dose-adjusted HbA1c), glycemic control, daily insulin requirements, diabetic ketoacidosis (DKA) and diabetes-related autoantibodies (IA-2A, GADA, ICA, ZnT8Ab) in children during the first year after diagnosis of type 1 diabetes.. The C1858T variant was genotyped in an international cohort of children (n = 257 patients) with newly diagnosed type 1 diabetes during 12 months after onset. We investigated the association of this variant with liquid-meal stimulated beta-cell function (proinsulin and C-peptide) and antibody status 1, 6 and 12 months after onset. In addition HbA1c and daily insulin requirements were determined 1, 3, 6, 9 and 12 months after diagnosis. DKA was defined at disease onset.. A repeated measurement model of all time points showed the stimulated proinsulin level is significantly higher (22%, p = 0.03) for the T allele carriers the first year after onset. We also found a significant positive association between proinsulin and IA levels (est.: 1.12, p = 0.002), which did not influence the association between PTPN22 and proinsulin (est.: 1.28, p = 0.03).. The T allele of the C1858T variant is positively associated with proinsulin levels during the first 12 months in newly diagnosed type 1 diabetes children. Topics: Autoantibodies; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Enzyme-Linked Immunosorbent Assay; Female; Genetic Predisposition to Disease; Humans; Male; Polymorphism, Single Nucleotide; Proinsulin; Protein Tyrosine Phosphatase, Non-Receptor Type 22; Regression Analysis; Time Factors | 2011 |
Basal insulin requirement is ~30% of the total daily insulin dose in type 1 diabetic patients who use the insulin pump.
To investigate the basal insulin requirement in total daily insulin dose in Japanese type 1 diabetic patients who use the insulin pump.. The basal insulin requirement in 35 type 1 diabetic patients without detectable C-peptide using the insulin pump (Paradigm 712) was investigated during 2-3 weeks of hospitalization. The patients were served diabetic diets of 25-30 kcal/kg ideal body weight. Each meal omission was done to confirm stable blood glucose levels within 30 mg/dL variance until the next meal. Target blood glucose level was set at 100 mg/dL before each meal and 150 mg/dL at 2 h after each meal.. Total daily insulin dose was 31.6 ± 8.5 units, and total basal insulin requirement was 8.7 ± 2.9 units, which was 27.7 ± 6.9% of the total daily dose.. Basal insulin requirement is ~30% of the total daily dose in Japanese type 1 diabetic patients who use the insulin pump. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Infusion Systems; Insulin, Long-Acting; Male; Middle Aged; Young Adult | 2011 |
Increased fat mass and cardiac septal hypertrophy in newborn infants of mothers with well-controlled diabetes during pregnancy.
Improved glycaemic control during pregnancy in mothers with type 1 diabetes (T1DM) and gestational diabetes (GDM) has resulted in a marked reduction of perinatal mortality and morbidity, but the prevalence of macrosomia is usually high.. We used non-invasive anthropometric methods to estimate the body composition and the thickness of the interventricular heart septum in 18 infants of mothers with well-controlled T1DM, 10 infants of mothers with GDM and 28 infants of healthy control mothers matched for gestational age and mode of delivery.. Skinfold measurements were obtained with a Harpenden calliper within 48 h after delivery. Echocardiography was also performed to measure the thickness of the interventricular septum. Cord blood was sampled for assays of C-peptide, leptin and IGF-I.. The rates of macrosomia (gestational age-adjusted birth weight >2 standard deviation score, SDS) were 56 and 30% in infants of mothers with T1DM and GDM, respectively, compared to 10% in control infants. The body fat content was 40% (0.2 kg) higher and the interventricular heart septum thickness was increased by 20% in both groups of infants of diabetic mothers. We found no associations between maternal levels of HbA1c during pregnancy and body composition or interventricular heart septum thickness. Cord levels of C-peptide and leptin were significantly higher in infants of T1DM mothers than in control infants. Cord leptin level was associated with birth weight SDS and percent body fat in infants of T1DM mothers. IGF-I was associated with percent body fat in infants of GDM mothers and control mothers. A multiple-regression analysis showed that 50% of the variation in body weight SDS could be determined, with IGF-I, leptin and C-peptide as independent variables.. Both fat mass and cardiac septal thickness are increased in newborn infants of women with T1DM and GDM in spite of efforts to achieve good glycaemic control during pregnancy. Topics: Adipose Tissue; Adult; Blood Glucose; Body Composition; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Fetal Macrosomia; Glycated Hemoglobin; Heart Septum; Humans; Hypertrophy; Infant, Newborn; Insulin-Like Growth Factor I; Leptin; Pregnancy; Prevalence; Regression Analysis | 2011 |
Metabolic tests to determine risk for type 1 diabetes in clinical trials.
Evaluate the reproducibility and relationship of various metabolic tests conducted as part of the Diabetes Prevention Trial-type 1 diabetes.. Coefficients of variation, intraclass correlation coefficients, and Pearson correlations between the same metabolic tests performed at different times as well as the different tests were determined.. Fasting samples on the same day had a coefficient of variation of < 10 for C-peptide, 11 for insulin, and 2 for glucose. Testing on separate days approximately doubled the variance. Stimulated insulin values had less variance than fasting values and there was only a moderate correlation between fasting and stimulated values on each test. While highly correlated, C-peptide values from mixed meal tolerance tests are significantly lower than that obtained during oral glucose tolerance tests (OGTTs). Neither peak nor area under the curve C-peptide on the oral glucose tolerance test was different between those with abnormal and normal glucose tolerance. Those with abnormal as compared with normal glucose tolerance had lower 30-min C-peptide and a longer time to peak C-peptide.. A large, multi-centre trial, with tests performed over a decade-long period, can provide robust data. C-peptide data from oral glucose tolerance tests and mixed meal tolerance tests differ; therefore, the same stimulation test should be used to evaluate changes in beta cell function over time. Worsening glucose tolerance is associated with lower C-peptide at 30 min and a delay in peak secretion on the oral glucose tolerance test. This Diabetes Prevention Trial-type 1 diabetes data can be used in planning parameters for future studies, including evaluation of new algorithms to determine risk of disease. Topics: Autoantibodies; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Fasting; Food; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Prediabetic State; Reproducibility of Results; Risk | 2011 |
Free fatty acids level may effect a residual insulin secretion in type 1 diabetes.
Recent studies on the pathogenesis of type 1 diabetes (T1DM) show that autoimmune activity in human pancreatic 1-cells is accompanied by abnormalities of fatty tissue metabolism, which is the underlying process in type 2 diabetes.The aim of the study was to determine the correlation between C-peptide concentration, indicating residual insulin secretion, and free fatty acids (FFA) level in children with T1DM.. We recruited 178 diabetic patients (mean age 10.8 years; M/F 99/79). In all individuals the fasting C-peptide by a radioimmunological method and FFA serum levels using an enzymatic colorimetric method were measured at the onset and after 6 months of the diabetes duration.. Thirty four (19.1%) of the patients had the C-peptide level above the lower limit of normal range (>0.28 pmol/ml) at both time points. FFA level at onset was significantly higher as compared to the level after 6 months of follow-up (38.4+29.4 vs. 28.9 ± 23.1 mg/dl; p=0.0003). However, both values were positively correlated (r=0.31; p=0.0008). Interestingly, a negative correlation was found between FFA and C-peptide measurements at onset (r=-0.19; p=0.01) and at 6th month of the disease (r=-0.18; p=0.02). Moreover, when the C-peptide level was treated as a binominal variable(above and below 0.28 pmol/ml) higher levels of FFA were observed in children with C-peptide deficiency at onset of diabetes (41.1 vs. 29.9 mg/dl; p=0.03) and a similar trend was noticed at 6th month of the disease (31.0 vs. 23.7 mg/dl; p=0.1). No relation of FFA with age at onset, gender,insulin requirement and HbA1c were revealed.. The obtained results, which link the FFA level with residual insulin secretion in T1DM,may serve as further evidence supporting the contribution of fatty tissue metabolism in the patho-genesis of T1DM. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Insulin Secretion; Male; Risk Factors | 2011 |
Persistently autoantibody negative (PAN) type 1 diabetes mellitus in children.
Autoantibody-negative children diagnosed with type 1 diabetes might have unrecognized monogenic or type 2 diabetes.. At diagnosis of type 1 diabetes (between ages 0.5 and 16.3 yr, n = 470), autoantibodies [glutamic acid decarboxylase (GAD), insulinoma-associated protein 2 (IA2), insulin autoantibodies (IAA), and/or islet cell antibody (ICA)] were positive (ab+) in 330 and negative in 37 (unknown in 103). Autoantibody-negative patients were retested at median diabetes duration of 3.2 yr (range 0.9-16.2) for autoantibodies (GAD, IA2, ZnT8), human leukocyte antigen (HLA) typing, non-fasting C-peptide, and sequencing of HNF4A, HNF1A, KCNJ11, and INS.. Nineteen (5% of 367) remained persistently autoantibody negative (PAN), 17 were positive on repeat testing (PORT), and 1 refused retesting. No mutations were found in PORT. One PAN was heterozygous for P112L mutation in HNF1A and transferred from insulin to oral gliclazide. Another PAN transferred to metformin and the diagnosis was revised to type 2 diabetes. The remaining 17 PAN were indistinguishable from the ab+ group by clinical characteristics. HLA genotype was at high risk for type 1 diabetes in 82% of remaining PAN and 100% of PORT. After excluding patients with diabetes duration <1 yr, C-peptide was detectable more frequently in the remaining PAN (7/16) and PORT (6/17) than in a random selection of ab+ (3/28, p = 0.03).. The diagnosis of type 1 diabetes should be reevaluated in PAN patients, because a subset has monogenic or type 2 diabetes. The remaining PAN have relatively preserved C-peptide compared with ab+, suggesting slower β-cell destruction, but a very high frequency of diabetogenic HLA, implying that type 1B (idiopathic) diabetes is rare. Topics: Adolescent; Australia; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Hepatocyte Nuclear Factor 1-alpha; Histocompatibility Testing; HLA Antigens; Humans; Infant; Seroepidemiologic Studies; White People; Young Adult | 2011 |
Diabetic ketoacidosis: persistence and paradox.
Topics: Adolescent; C-Peptide; Dehydration; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Humans; Hypertension; Infant; Insulin; Patient Compliance | 2011 |
Arresting type 1 diabetes after diagnosis: GAD is not enough.
Topics: Aluminum Hydroxide; Animals; Biomedical Research; C-Peptide; Diabetes Mellitus, Type 1; Disease Models, Animal; Glutamate Decarboxylase; Humans; Immunotherapy | 2011 |
Clinical characteristics of fulminant type 1 diabetes associated with pregnancy in China.
To report 12 cases of pregnancy-associated fulminant type 1 diabetes mellitus (PF) found in China from 2003 to 2010. The clinical and biochemical characteristics of these cases with PF were compared with a group of cases of child-bearing age with fulminant type 1 diabetes that was not associated with pregnancy (NPF). The clinical and biochemical characteristics of 12 PF cases were analyzed retrospectively and then compared with those characteristics of 20 NPF cases in China. The difference between Chinese and Japanese PF cases was investigated. The mean values of the characteristics from PF and NPF cases in China, including postprandial serum C-peptide concentration, plasma glucose concentration, and serum chloride were different. Compared to the 22 PF cases in Japan, the mean age of these 12 PF cases was much younger. The mean fasting and postprandial serum C-peptide concentration level were lower, and the mean HbA1c levels was higher in 12 PF cases in China. Eight of 12 PF cases in China developed the disease during pregnancy. Other four PF case developed the disease within 2 weeks after delivery. 12 PF cases in China showed more severe beta-cell destruction, the prognosis of their fetuses was extremely poor. Topics: Acidosis; Adolescent; Adult; Age of Onset; Blood Glucose; C-Peptide; China; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Middle Aged; Pregnancy; Retrospective Studies; Young Adult | 2011 |
Differentiation of PDX1 gene-modified human umbilical cord mesenchymal stem cells into insulin-producing cells in vitro.
Mesenchymal stem cells (MSCs) have significant advantages over other stem cell types, and greater potential for immediate clinical application. MSCs would be an interesting cellular source for treatment of type 1 diabetes. In this study, MSCs from human umbilical cord were differentiated into functional insulin-producing cells in vitro by introduction of the pancreatic and duodenal homeobox factor 1 (PDX1) and in the presence of induction factors. The expressions of cell surface antigens were detected by flow cytometry. After induction in an adipogenic medium or an osteogenic medium, the cells were observed by Oil Red O staining and alkaline phosphatase staining. Recombinant adenovirus carrying the PDX1 gene was constructed and MSCs were infected by the recombinant adenovirus, then treated with several inducing factors for differentiation into islet β-like cells. The expression of the genes and protein related to islet β-cells was detected by immunocytochemistry, RT-PCR and Western blot analysis. Insulin and C-peptide secretion were assayed. Our results show that the morphology and immunophenotype of MSCs from human umbilical cord were similar to those present in human bone marrow. The MSCs could be induced to differentiate into osteocytes and adipocytes. After induction by recombined adenovirus vector with induction factors, MSCs were aggregated and presented islet-like bodies. Dithizone staining of these cells was positive. The genes' expression related to islet β-cells was found. After induction, insulin and C-peptide secretion in the supernatant were significantly increased. In conclusion, our results demonstrated that PDX1 gene-modified human umbilical cord mesenchymal stem cells could be differentiated into insulin-producing cells in vitro. Topics: Adenoviridae; Adipocytes; C-Peptide; Cell Differentiation; Cell Transplantation; Cells, Cultured; Diabetes Mellitus, Type 1; Fetal Blood; Flow Cytometry; Genetic Vectors; Homeodomain Proteins; Humans; Immunohistochemistry; Immunophenotyping; Insulin; Insulin Secretion; Insulin-Secreting Cells; Mesenchymal Stem Cells; Osteocytes; Reverse Transcriptase Polymerase Chain Reaction; Trans-Activators; Transduction, Genetic; Umbilical Cord | 2011 |
The message for MODY.
Topics: Autoantibodies; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Glucagon; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Immunologic Factors; Male; Mutation; RNA, Messenger; Transcription, Genetic | 2011 |
Urine C-peptide creatinine ratio is an alternative to stimulated serum C-peptide measurement in late-onset, insulin-treated diabetes.
Serum C-peptide measurement can assist clinical management of diabetes, but practicalities of collection limit widespread use. Urine C-peptide creatinine ratio may be a non-invasive practical alternative. The stability of C-peptide in urine allows outpatient or community testing. We aimed to assess how urine C-peptide creatinine ratio compared with serum C-peptide measurement during a mixed-meal tolerance test in individuals with late-onset, insulin-treated diabetes.. We correlated the gold standard of a stimulated serum C-peptide in a mixed-meal tolerance test with fasting and stimulated (mixed-meal tolerance test, standard home meal and largest home meal) urine C-peptide creatinine ratio in 51 subjects with insulin-treated diabetes (diagnosis after age 30 years, median age 66 years, median age at diagnosis 54, 42 with Type 2 diabetes, estimated glomerular filtration rate > 60 ml min(-1) 1.73 m(-2) ).. Ninety-minute mixed-meal tolerance test serum C-peptide is correlated with mixed-meal tolerance test-stimulated urine C-peptide creatinine ratio (r = 0.82), urine C-peptide creatinine ratio after a standard breakfast at home (r = 0.73) and urine C-peptide creatinine ratio after largest home meal (r = 0.71). A stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.3 nmol/mmol had a 100% sensitivity and 96% specificity (area under receiver operating characteristic curve = 0.99) in identifying subjects without clinically significant endogenous insulin secretion (mixed-meal tolerance test-stimulated C-peptide < 0.2 nmol/l). In detecting a proposed serum C-peptide threshold for insulin requirement (stimulated serum C-peptide < 0.6 nmol/l), a stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.6 nmol/mmol had a sensitivity and specificity of 92%.. In patients with insulin-treated diabetes diagnosed after age 30 years, urine C-peptide creatinine ratio is well correlated with serum C-peptide and may provide a practical alternative measure to detect insulin deficiency for use in routine clinical practice. Topics: Age of Onset; Aged; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Male; Middle Aged; Sensitivity and Specificity | 2011 |
Long-term metabolic and immunological follow-up of nonimmunosuppressed patients with type 1 diabetes treated with microencapsulated islet allografts: four cases.
To assess long-term metabolic and immunological follow-up of microencapsulated human islet allografts in nonimmunosuppressed patients with type 1 diabetes (T1DM).. Four nonimmunosuppressed patients, with long-standing T1DM, received intraperitoneal transplant (TX) of microencapsulated human islets. Anti-major histocompatibility complex (MHC) class I-II, GAD65, and islet cell antibodies were measured before and long term after TX.. All patients turned positive for serum C-peptide response, both in basal and after stimulation, throughout 3 years of posttransplant follow-up. Daily mean blood glucose, as well as HbA(1c) levels, significantly improved after TX, with daily exogenous insulin consumption declining in all cases and being discontinued, just transiently, only in patient 4. Anti-MHC class I-II and GAD65 antibodies all tested negative at 3 years after TX.. The grafts did not elicit any immune response, even in the cases where more than one preparation was transplanted, as a unique finding, compatible with encapsulation-driven "bioinvisibility" of the grafted islets. This result had never been achieved with the recipient's general immunosuppression. Topics: Adult; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Immunosuppression Therapy; Islets of Langerhans; Islets of Langerhans Transplantation; Major Histocompatibility Complex; Transplantation, Homologous; Treatment Outcome | 2011 |
Impact of the number of infusions on 2-year results of islet-after-kidney transplantation in the GRAGIL network.
Insulin independence after islet transplantation is generally achieved after multiple infusions. However, single infusion would increase the number of recipients. Our aim was to evaluate the results of islet-after-kidney transplantation according to the number of infusions.. Islets were isolated at the Geneva University, shipped, and transplanted into French patients from the Swiss-French GRAGIL network, on the "Edmonton" immunosuppression protocol between 2004 and 2010.. Nineteen patients were transplanted with 33 preparations. Fifteen patients reached 24 months follow-up; eight subjects were single-graft recipients and seven were double-graft recipients. Finally, single-graft recipients received a median of 5312 islet equivalents/kg (5186-6388) vs. 10,564 (10,054-11,375) for double-graft recipients (P=0.0003) with similar islet mass at first infusion. Insulin independence was achieved in five of eight single-graft subjects (62.5%) versus five of seven in double-graft subjects (71.4%), not significant. Median insulin independence duration was 4.7 (3.1-15.2) months after one infusion vs. 19 (9.6-20.8) months after two infusions (not significant). At 24 months posttransplant, comparing single- with double-graft patients, insulin doses were 0.23 (0.11-0.34) U/kg vs. 0.02 (0.0-0.23) U/kg, P=0.11; HbA1c was 6.5% (5.9%-6.8%) vs. 6.2% (5.9%-6.3%), P=0.16; and basal C-peptide was 302 (143-480) pmol/L vs. 599 (393-806) pmol/L, P=0.05. Only 37.5% of single-graft patients had a β-score ≥4 compared with 100% of double-graft patients (P=0.03). Two recipients experienced postinfusion bleeding, and two patients (13%) showed renal dysfunction in the absence of biopsy-proven rejection.. One infusion achieves good glycemic control and sometimes insulin independence. However, double-graft patients remain insulin-free longer, tend to have lower HbA1c, and show better graft function 24 months after transplant. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; France; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Longitudinal Studies; Male; Middle Aged; Retrospective Studies; Time Factors; Treatment Outcome | 2011 |
GAD antibodies in T1D and LADA--relations to age, BMI, c-peptide, IA-2 and HLA-DRB1*03 and DRB1*04 alleles.
The determination of GADA may be useful for clinical classification of diabetes mellitus (DM) in clinically unclear cases. This GADA positivity may persist in any diabetics Type 1 Diabetes Mellitus (T1D) with an onset in adulthood and Late Autoimmune Diabetes of Adults (LADA) many years after appearance of DM. The study was aimed at comparing the levels of GADA between both diabetic subsets with their clinical parameters, age of onset DM, period of insulin need, body mass index, HbA1C, fasting and postprandial C-peptide, risky HLA-DRB1* alleles, occurrence of micro- and macrovascular diabetic complications. Further analysis of GADA titers in different time consequences to the development of DM and relations to IA-2 were made. In the study, we included 130 diabetics with an onset of diabetes (T1D or LADA) 35+ y. who were hospitalized and afterwards long-term observed in the diabetological outpatient department. Out of this number there were 62 men and 68 women of the average age 65.5 +/- 14.0 y. (range 35-93 y.). 54 were assessed as the T1D patients and 76 as the LADA ones. Patients of the T1D subgroup were GADA positive 22 times and of the LADA subgroup 21 times. LADA 2 patients that were GADA negative were more obese than GADA positive LADA diabetics (p < 0.01). Also postprandial C-peptide was higher in LADA patients GADA negative (p < 0.05). Other clinical characteristics were without statistically significant differences. We found in our diabetic patients a relation between alleles HLA-DRB1*03 and particularly combination with HLA-DRB1*04 with positive GADA levels. In the GADA negative group obesity, coronary heart disease, hypertension, syndrome of diabetic foot and dyslipidaemia appeared more frequently (OR = 2.8; 3.1; 6.2 and 2.4). We found no significant differences in observed parameters--comparison GADA positivity and negativity according to the duration of DM. GADA positive were even 10 y. duration 16 times and after 20 y. even 6 times. Recent DM had positive GADA in 11 cases and 13 cases of recent DM had GADA negative. IA-2 antibodies were positive (> 1.0 U/ml) 18 times altogether and always with positive GADA, but only 7 times in recent DM. The presence of elevated GADA identifies patients unequivocally suitable for early insulin therapy. Our observations and experiences confirm that GADA can be found increased after more than 10-20 years duration of DM, although in decreasing trend. Topics: Adult; Aged; Aged, 80 and over; Alleles; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Male; Middle Aged; Receptor-Like Protein Tyrosine Phosphatases, Class 8 | 2011 |
Serum CXCL1 concentrations are elevated in type 1 diabetes mellitus, possibly reflecting activity of anti-islet autoimmune activity.
Identification of unique inflammatory markers may facilitate prediction of type 1 diabetes mellitus (T1DM). We previously compared transcript profiles of bone marrow-derived dendritic cells from non-obese diabetic mice with those from non-obese non-diabetic mice and found that bone marrow-derived dendritic cells' expressions of inflammatory mediators, including chemokine (C-X-C motif) ligand 1 (CXCL1), were three to five times higher in 4-week-old female non-obese diabetic mice than in non-obese non-diabetic mice. In humans, microarray analysis results have suggested this chemokine be a biomarker representing active anti-islet autoimmunity. We investigated whether serum CXCL1 levels, reflecting active autoimmune processes, might serve as biomarkers for T1DM.. The study groups consisted of 26 subjects with acute-onset T1DM, 20 with slowly progressive T1DM, and 20 with type 2 diabetes mellitus as disease controls. All subjects were Japanese. CXCL1 in sera were quantified by solid phase enzyme-linked immunosorbent assays.. Serum CXCL1 levels were significantly higher in subjects with acute-onset [median 113.2 ng/mL (41.75-457.2)] or slowly progressive [median 100.8 ng/mL (32.87-225.0)] T1DM than in those with type 2 diabetes mellitus [median 71.58 ng/mL (32.45-152.6), p=0.01 and 0.03, respectively, Mann-Whitney U-test]. Decreases in fasting C-peptide levels per year correlated significantly with CXCL1 levels (n=11, r2=0.524, p=0.012) in a subpopulation of slowly progressive T1DM subjects displaying preserved beta-cell function.. To our knowledge, this is the first study to show elevated serum CXCL1 in T1DM subjects, regardless of diabetes subtype, as compared to control type 2 diabetes mellitus subjects. We propose serum CXCL1 elevation to be a good T1DM marker, possibly indicating a predisposition to autoimmune disease development. Topics: Adolescent; Adult; Aged; C-Peptide; Chemokine CXCL1; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged | 2011 |
Heterogeneity among patients with latent autoimmune diabetes in adults.
Some type 1 diabetic patients do not require insulin at diagnosis of diabetes, and they progress to insulin dependence only after several years (latent autoimmune diabetes in adults). However, not all patients with latent autoimmune diabetes in adults progress to insulin dependence. We compared the characteristics of patients with high glutamic acid decarboxylase antibodies (GADA) titres (≥10 U/mL) to those of patients with low titres and examined other factors possibly associated with the progression to insulin dependence.. We began registering diabetic patients in 1993 and have since followed them prospectively. Among these patients, we analysed clinical characteristics and progression to insulin dependence in those followed for more than 5 years.. Patients with high GADA titres were younger and had lower body mass index, shorter disease durations and lower serum C-peptide (s-CPR) levels than the patients with low GADA titre and GADA negative type 2 diabetes. Frequencies of other islet-related autoantibodies were significantly higher in patients with high GADA titre than in those with low GADA titres. Disease protective HLA class II genotypes were less frequent in patients with high titre. The positive predictive value of being GADA positive was only 42.7%. The positive predictive value increased to 78.6% when the cut-off was set at the relatively high level of 10 U/mL. Combining GADA with other islet-related autoantibodies or HLA class II genotype increased positive predictive value but decreased sensitivity.. Our results suggest that latent autoimmune diabetes in adults constitutes a heterogeneous group and that the majority of patients with high GADA titres (≥10 U/mL) will ultimately develop type 1 diabetes while those with low titres include patients with type 1 and type 2 diabetes. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Insulin; Insulin Resistance; Islets of Langerhans; Male; Middle Aged; Predictive Value of Tests; Prospective Studies; Sensitivity and Specificity | 2011 |
Age-corrected beta cell mass following onset of type 1 diabetes mellitus correlates with plasma C-peptide in humans.
The inability to produce insulin endogenously precipitates the clinical symptoms of type 1 diabetes mellitus. However, the dynamic trajectory of beta cell destruction following onset remains unclear. Using model-based inference, the severity of beta cell destruction at onset decreases with age where, on average, a 40% reduction in beta cell mass was sufficient to precipitate clinical symptoms at 20 years of age. While plasma C-peptide provides a surrogate measure of endogenous insulin production post-onset, it is unclear as to whether plasma C-peptide represents changes in beta cell mass or beta cell function. The objective of this paper was to determine the relationship between beta cell mass and endogenous insulin production post-onset.. Model-based inference was used to compare direct measures of beta cell mass in 102 patients against contemporary measures of plasma C-peptide obtained from three studies that collectively followed 834 patients post-onset of clinical symptoms. An empirical Bayesian approach was used to establish the level of confidence associated with the model prediction. Age-corrected estimates of beta cell mass that were inferred from a series of landmark pancreatic autopsy studies significantly correlate (p>0.9995) with contemporary measures of plasma C-peptide levels following onset.. Given the correlation between beta cell mass and plasma C-peptide following onset, plasma C-peptide may provide a surrogate measure of beta cell mass in humans. The clinical relevance of this study is that therapeutic strategies that provide an increase in plasma C-peptide over the predicted value for an individual may actually improve beta cell mass. The model predictions may establish a standard historical "control" group - a prior in a Bayesian context - for clinical trials. Topics: Bayes Theorem; C-Peptide; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans | 2011 |
Association between the secretory unit of islet transplant objects index and satisfaction with insulin therapy among insulin-dependent islet recipients.
When patients do not become insulin independent after islet cell transplantation (ICT), another aim is to eliminate severe hypoglycemia. Previously we reported that a secretory unit of islet transplant objects (SUITO) index score >10 was associated with a reduction of severe hypoglycemia. In this study, we assessed patients' satisfaction with their insulin therapy based on the SUITO index.. The study involved 11 islet recipients with type 1 diabetes who underwent ICT but still used insulin. From those patients, 41 Insulin Therapy Satisfaction Questionnaires (ITSQ) were collected. The SUITO index (fasting C-peptide [ng/mL] × 1500/blood glucose [mg/dL] - 63) was calculated at the same outpatient visits that the survey was administered. ITSQ scores were summarized using subscales and compared among 3 groups: the pre-ICT group, the low-SUITO group (SUITO index score <10 post-ICT), and the high-SUITO group (SUITO index score ≥10). Higher survey scores indicated better satisfaction.. Significant trend relationships across the 3 groups were observed in the ITSQ total score (P = .02 with Jonckheere-Terpstra test) and subscale scores of glycemic control (P < .001), hypoglycemic control (P = .01), and inconvenience of regimen (P = .004). The pairwise comparisons between the 3 groups found significant differences: high SUITO versus both pre-ICT and low SUITO for the total ITSQ score (P = .03 and .005, respectively) and glycemic control score (P = .008 and .001, respectively), and high SUITO versus low SUITO for hypoglycemic control score (P = .04) and inconvenience of regimen score (P = .008).. Islet recipients with a SUITO index ≥10 experienced higher satisfaction with insulin injection therapy compared with the pre-ICT group, even though they were insulin dependent. A SUITO index ≥10 is a reasonable benchmark for successful ICT. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Graft Survival; Humans; Hypoglycemia; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Outpatients; Patient Satisfaction; Surveys and Questionnaires; Treatment Outcome | 2011 |
The effect of the length of the prodromal period on the metabolic control within the first 2 years in children with diabetic ketoacidosis manifestation.
We investigated the effects of clinical and laboratory properties at the time of the initial application of patients recently diagnosed and presenting metabolic indicators of diabetic ketoacidosis who were given disease prognoses in years 1 and 2 after discharge.. A total of 94 patients admitted to Bakirkoy Maternity and Children's Diseases Training and Research Hospital with diabetic ketoacidosis and recently diagnosed with type 1 diabetes mellitus were investigated. Patient files were examined within 2 years following discharge.. All 94 study patients (53.2% male and 46.8% female) presented acidosis, ketonuria and hyperglycemia. While a moderate correlation was detected between the prodromal period and HbA(1c) values in year 1, only a slight correlation was seen in HbA(1c) values in year 2. In addition, a slight correlation was observed between the prodromal period and the number of hospitalizations due to diabetic ketoacidosis in the first year. Again, while a moderate correlation was observed between HbA(1c) values and the number of hospitalizations due to diabetic ketoacidosis in year 1, only a slight correlation was seen in year 2. The prodromal period was directly proportional to patient age.. Hospital admissions may be reduced through appropriate treatment, follow-up and metabolic control of patients with type 1 diabetes mellitus. In addition, we report a relationship between the prodromal period and HbA(1c) values in type 1 diabetes patients. Topics: Blood Glucose; C-Peptide; Child; Child, Hospitalized; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Progression; Female; Glycated Hemoglobin; Humans; Incidence; Insulin; Male; Patient Readmission | 2011 |
Fulminant type 1 diabetes mellitus in Korean adolescents.
Fulminant type 1 diabetes has recently been identified as a new subtype of idiopathic diabetes that is mostly found in Japanese adults. The aim of this study was to investigate the frequency as well as the clinical and laboratory characteristics of fulminant type 1 diabetes among Korean children with childhood-onset type 1 diabetes. One-hundred and fifty patients that had been newly diagnosed with type 1 diabetes over the past 10 years were included. These patients came from three hospitals. Out of the 150 patients, two female patients fulfilled the criteria for fulminant type 1 diabetes. They were negative for islet autoantibodies. The patients with fulminant type 1 diabetes had an older age of onset and a lower HbA1c than the patients with autoimmune or idiopathic type 1 diabetes. In addition, the patients with fulminant type 1 diabetes had increased serum aspartate aminotransferase, alanine aminotransferase and amylase levels, and decreased fasting serum C-peptide levels. The frequency of fulminant type 1 diabetes was 1.33% among all patients newly diagnosed with type 1 diabetes under the age of 16. Although this type of diabetes is more commonly an adult-onset disease, it is possible that fulminant type 1 diabetes has not yet been fully recognized in children and adolescence, and may be more common than initially thought. Topics: Adolescent; Age of Onset; Alanine Transaminase; Asian People; Aspartate Aminotransferases; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Republic of Korea; Seroepidemiologic Studies; Severity of Illness Index | 2011 |
Transcription factor 7-like 2-gene polymorphism is related to fasting C peptide in latent autoimmune diabetes in adults (LADA).
Common polymorphisms in the transcription factor 7-like 2 gene (TCF7L2) have been associated with type 2 diabetes in different populations and recently with LADA, but not with type 1 diabetes. The aim of our study was to investigate association between the rs7903146 polymorphism in the TCF7L2 gene and LADA in Polish patients. Link between the "high risk for type 2 diabetes genotype" with clinical features was analyzed. 68 newly diagnosed patients with LADA and 195 healthy controls were genotyped for the rs7903146 polymorphism in the TCF7L2 gene using the PCR-based RFLP method. Fasting C peptide level was measured by ELISA. We observed increased frequencies of the TT genotype of the rs7903146 polymorphism in the TCF7L2 gene in LADA patients compared to controls (15 vs. 6%, P = 0.03). Fasting C peptide serum concentration was significantly lower in group of patients with LADA carrying the TT genotype (P < 0.01). In conclusion, the data from this study confirmed previous results showing genetic similarities between patients with LADA and type 2 diabetes. Non-autoimmune mechanism may be related to beta cell dysfunction in patients with LADA. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; DNA Primers; Fasting; Female; Glucose Intolerance; Humans; Male; Middle Aged; Polymorphism, Genetic; Predictive Value of Tests; Reference Values; TCF Transcription Factors; Transcription Factor 7-Like 2 Protein | 2010 |
Multinational study in children and adolescents with newly diagnosed type 1 diabetes: association of age, ketoacidosis, HLA status, and autoantibodies on residual beta-cell function and glycemic control 12 months after diagnosis.
To identify predictors of residual beta-cell function and glycemic control during the first 12 months after the diagnosis of type 1 diabetes (T1D).. Clinical information and blood samples were collected from 275 children. HbA1c, antibodies, HLA typing and mixed meal-stimulated C-peptide levels 1, 6, and 12 months after diagnosis were analyzed centrally.. Mean age at diagnosis was 9.1 yr. DKA with standard bicarbonate <15 mmol/L was associated with significantly poorer residual beta-cell function 1 (p = 0.004) and 12 months (p = 0.0003) after diagnosis. At 12 months, the decline in stimulated C-peptide levels compared with the levels at 1 month was 69% in the youngest age group and 50% in patients 10 yr and above (p < 0.001). Stimulated C-peptide at 12 months was predicted by younger age (p < 0.02) and bicarbonate levels at diagnosis (p = 0.005), and by stimulated C-peptide (p < 0.0001), postmeal blood glucose (p = 0.0004), insulin antibodies (IA; p = 0.02) and glutamic acid decarboxylase antibodies (GADA; p = 0.0004) at 1 month. HbA1c at 12 months was predicted by HbA1c at diagnosis (p < 0.0001), GADA at 1 month (p = 0.01), and non-white Caucasian ethnicity (p = 0.002).. Younger age, ketoacidosis at diagnosis, and IA and GADA 1 month after diagnosis were the strongest explanatory factors for residual beta-cell function at 12 months. Glycemic control at 12 months was influenced predominantly by ethnicity, HbA1c at diagnosis, and GADA at 1 month. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glutamate Decarboxylase; Glycated Hemoglobin; HLA Antigens; Humans; Hypoglycemic Agents; Infant; Insulin; Insulin Antibodies; Insulin-Secreting Cells; Male; Multicenter Studies as Topic; Prospective Studies; Treatment Outcome | 2010 |
Predicting islet yield in pediatric patients undergoing pancreatectomy and autoislet transplantation for chronic pancreatitis.
Chronic pancreatitis (CP) in children is associated with significant morbidity and can lead to narcotic dependence. Total pancreatectomy (TP) may be indicated in refractory CP to relieve pain; simultaneous islet autotransplant (IAT) may prevent postsurgical diabetes. About half of pediatric patients are insulin independent 1 yr after IAT. Insulin independence correlates best with the number of islets available for transplantation (islet yield). Currently there is no known method to predict islet yield in a given patient. We assessed the ability of preoperative metabolic tests to predict islet yields in 10 children undergoing TP/IAT.. Hemoglobin A1c (HbA(1c)) and mixed meal tolerance tests (MMTT) were obtained prior to surgery in 10 patients age Topics: Adolescent; Blood Glucose; C-Peptide; Carrier Proteins; Child; Child, Preschool; Creatinine; Cystic Fibrosis Transmembrane Conductance Regulator; Diabetes Mellitus, Type 1; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Pain, Intractable; Pancreatectomy; Pancreatitis, Chronic; Prospective Studies; Transplantation, Autologous; Treatment Outcome; Trypsin; Trypsin Inhibitor, Kazal Pancreatic | 2010 |
Pdx1-transfected adipose tissue-derived stem cells differentiate into insulin-producing cells in vivo and reduce hyperglycemia in diabetic mice.
Insulin-dependent diabetes mellitus (IDDM) is characterized by the rapid development of potentially severe metabolic abnormalities resulting from insulin deficiency. The transplantation of insulin-producing cells is a promising approach for the treatment of IDDM. The transcription factor pancreatic duodenal homeobox 1 (Pdx1) plays an important role in the differentiation of pancreatic beta cells. In this study, the human Pdx1 gene was transduced and expressed in murine adipose tissue-derived stem cells (ASCs). To evaluate pancreatic repair, we used a mouse model of pancreatic damage resulting in hyperglycemia, which involves injection of mice with streptozotocin (STZ). STZ-treated mice transplanted with Pdx1-transduced ASCs (Pdx1-ASCs) showed significantly decreased blood glucose levels and increased survival, when compared with control mice. While stable expression of Pdx1 in ASCs did not induce the pancreatic phenotype in vitro in our experiment, the transplanted stem cells became engrafted in the pancreas, wherein they expressed insulin and C-peptide, which is a marker of insulin-producing cells. These results suggest that Pdx1-ASCs are stably engrafted in the pancreas, acquire a functional beta-cell phenotype, and partially restore pancreatic function in vivo. The ease and safety associated with extirpating high numbers of cells from adipose tissues support the applicability of this system to developing a new cell therapy for IDDM. Topics: Adipose Tissue; Animals; C-Peptide; Cell Differentiation; Diabetes Mellitus; Diabetes Mellitus, Type 1; Homeodomain Proteins; Humans; Hyperglycemia; Insulin; Insulin-Secreting Cells; Mice; Pancreas; Stem Cell Transplantation; Stem Cells; Streptozocin; Trans-Activators | 2010 |
Glycated albumin and glycated hemoglobin are influenced differently by endogenous insulin secretion in patients with type 2 diabetes.
Glycated albumin (GA) relative to A1C is a useful marker of short-term glycemic control. We investigated whether endogenous insulin secretion in type 2 diabetes has different effects on GA and A1C levels.. A1C, GA, and GA-to-A1C ratio were compared in 202 type 2 diabetic patients by type of treatment. Effect of beta-cell function determined by homeostasis model assessment (HOMA-%beta) on GA-to-A1C ratio was examined. In addition, GA-to-A1C ratio was compared between type 2 diabetic patients and 16 patients with type 1 diabetes.. In type 2 diabetic patients, GA-to-A1C ratio was significantly higher in those treated with insulin than in those treated with diet or oral hypoglycemic agents. HOMA-%beta showed a significant inverse correlation with GA-to-A1C ratio. This ratio was higher in type 1 diabetic patients than in type 2 diabetic patients.. In diabetic patients with decreased insulin secretion, serum GA levels are higher relative to A1C. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Glycated Serum Albumin; Glycation End Products, Advanced; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male; Patient Selection; Postprandial Period; Serum Albumin | 2010 |
A genome-wide association study identifies a novel major locus for glycemic control in type 1 diabetes, as measured by both A1C and glucose.
Glycemia is a major risk factor for the development of long-term complications in type 1 diabetes; however, no specific genetic loci have been identified for glycemic control in individuals with type 1 diabetes. To identify such loci in type 1 diabetes, we analyzed longitudinal repeated measures of A1C from the Diabetes Control and Complications Trial.. We performed a genome-wide association study using the mean of quarterly A1C values measured over 6.5 years, separately in the conventional (n = 667) and intensive (n = 637) treatment groups of the DCCT. At loci of interest, linear mixed models were used to take advantage of all the repeated measures. We then assessed the association of these loci with capillary glucose and repeated measures of multiple complications of diabetes.. We identified a major locus for A1C levels in the conventional treatment group near SORCS1 (10q25.1, P = 7 x 10(-10)), which was also associated with mean glucose (P = 2 x 10(-5)). This was confirmed using A1C in the intensive treatment group (P = 0.01). Other loci achieved evidence close to genome-wide significance: 14q32.13 (GSC) and 9p22 (BNC2) in the combined treatment groups and 15q21.3 (WDR72) in the intensive group. Further, these loci gave evidence for association with diabetic complications, specifically SORCS1 with hypoglycemia and BNC2 with renal and retinal complications. We replicated the SORCS1 association in Genetics of Diabetes in Kidneys (GoKinD) study control subjects (P = 0.01) and the BNC2 association with A1C in nondiabetic individuals.. A major locus for A1C and glucose in individuals with diabetes is near SORCS1. This may influence the design and analysis of genetic studies attempting to identify risk factors for long-term diabetic complications. Topics: Blood Glucose; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Drug Administration Schedule; Ethnicity; Genome-Wide Association Study; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Insulin; Meta-Analysis as Topic; Patient Selection; Polymorphism, Single Nucleotide; Racial Groups; Receptors, Cell Surface; Reference Values; Siblings | 2010 |
Hyperglycaemic clamp test for diabetes risk assessment in IA-2-antibody-positive relatives of type 1 diabetic patients.
The aim of the study was to investigate the use of hyperglycaemic clamp tests to identify individuals who will develop diabetes among insulinoma-associated protein-2 antibody (IA-2A)-positive first-degree relatives (IA-2A(+) FDRs) of type 1 diabetic patients.. Hyperglycaemic clamps were performed in 17 non-diabetic IA-2A(+) FDRs aged 14 to 33 years and in 21 matched healthy volunteers (HVs). Insulin and C-peptide responses were measured during the first (5-10 min) and second (120-150 min) release phase, and after glucagon injection (150-160 min). Clamp-induced C-peptide release was compared with C-peptide release during OGTT.. Seven (41%) FDRs developed diabetes 3-63 months after their initial clamp test. In all phases they had lower C-peptide responses than non-progressors (p < 0.05) and HVs (p < 0.002). All five FDRs with low first-phase release also had low second-phase release and developed diabetes 3-21 months later. Two of seven FDRs with normal first-phase but low second-phase release developed diabetes after 34 and 63 months, respectively. None of the five FDRs with normal C-peptide responses in all test phases has developed diabetes so far (follow-up 56 to 99 months). OGTT-induced C-peptide release also tended to be lower in progressors than in non-progressors or HVs, but there was less overlap in results between progressors and the other groups using the clamp.. Clamp-derived functional variables stratify risk of diabetes in IA-2A(+) FDRs and may more consistently identify progressors than OGTT-derived variables. A low first-phase C-peptide response specifically predicts impending diabetes while a low second-phase response may reflect an earlier disease stage.. ClinicalTrials.gov NCT00654121. The insulin trial was financially supported by Novo Nordisk Pharma nv. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Family; Glucose Clamp Technique; HLA-DQ Antigens; Humans; Hyperglycemia; Insulin; Medical History Taking; Reference Values; Risk Assessment; Young Adult | 2010 |
The over 50 year clinical course of a patient with slowly progressive type 1 diabetes (SPIDDM).
Type 1 diabetic patients who have endured their condition for prolonged periods are not uncommon, but there are few well-documented cases of type 2 diabetic patients with duration of over fifty years. In the present case study, we analyzed the history of a diabetic patient whose duration was 53 years. Her case was consequently diagnosed not as the common type 2 diabetes, but as the slowly progressive type 1 diabetes (SPIDDM) identified by Japanese medical researchers. The patient, now 73 years old, was first diagnosed with diabetes in 1953 when she was 17 years of age and started insulin injections. In 1962 she was referred to our hospital, and two years later she vaginally delivered a healthy baby (birth weight 3100 g) at the 40(th) week of gestation. She was the first case of a diabetic mother delivering an infant treated at Tokyo Women's Medical College Hospital. Her data shows that her C-peptide responses by meal tolerance test in 1978 was at least partly preserved though it decreased year by year. Her anti-GAD antibody was found to be positive in 2000 and remained so in 2009. This leads us to conclude that the etiology of her SPIDDM was most likely has insulin secretion exhaustion. Topics: Adolescent; Aged; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Female; Glutamate Decarboxylase; Humans; Hyperthyroidism; Infant, Newborn; Insulin; Insulin Secretion; Male; Pregnancy; Pregnancy in Diabetics | 2010 |
Measuring and detecting associations: methods based on robust regression estimators or smoothers that allow curvature.
This paper considers the problem of estimating the overall strength of an association, including situations where there is curvature. The general strategy is to fit a robust regression line, or some type of smoother that allows curvature, and then use a robust analogue of explanatory power, say eta(2). When the regression surface is a plane, an estimate of eta(2) via the Theil-Sen estimator is found to perform well, relative to some other robust regression estimators, in terms of mean squared error and bias. When there is curvature, a generalization of a kernel estimator derived by Fan performs relatively well, but two alternative smoothers have certain practical advantages. When eta(2) is approximately equal to zero, estimation using smoothers has relatively high bias. A variation of eta(2) is suggested for dealing with this problem. Methods for testing H(0): eta(2)=0 are examined that are based in part on smoothers. Two methods are found that control Type I error probabilities reasonably well in simulations. Software for applying the more successful methods is provided. Topics: Association Learning; Bias; C-Peptide; Child; Computer Graphics; Computer Simulation; Diabetes Mellitus, Type 1; Humans; Mathematical Computing; Reaction Time; Reading; Regression Analysis; Statistics as Topic; Verbal Behavior | 2010 |
Progression to diabetes in relatives of type 1 diabetic patients: mechanisms and mode of onset.
Relatives of type 1 diabetic patients are at enhanced risk of developing diabetes. We investigated the mode of onset of hyperglycemia and how insulin sensitivity and beta-cell function contribute to the progression to the disease.. In 328 islet cell autoantibody-positive, nondiabetic relatives from the observational arms of the Diabetes Prevention Trial-1 Study (median age 11 years [interquartile range 8], sequential OGTTs (2,143 in total) were performed at baseline, every 6 months, and 2.7 years [2.7] later, when 115 subjects became diabetic. Beta-cell glucose sensitivity (slope of the insulin-secretion/plasma glucose dose-response function) and insulin sensitivity were obtained by mathematical modeling of the OGTT glucose/C-peptide responses.. In progressors, baseline insulin sensitivity, fasting insulin secretion, and total postglucose insulin output were similar to those of nonprogressors, whereas beta-cell glucose sensitivity was impaired (median 48 pmol/min per m2 per mmol/l [interquartile range 36] vs. 87 pmol/min per m2 per mmol/l [67]; P < 0.0001) and predicted incident diabetes (P < 0.0001) independently of sex, age, BMI, and clinical risk. In progressors, 2-h glucose levels changed little until 0.78 years before diagnosis, when they started to rise rapidly (approximately 13 mmol x l(-1) x year(-1)); glucose sensitivity began to decline significantly (P < 0.0001) earlier (1.45 years before diagnosis) than the plasma glucose surge. During this anticipation phase, both insulin secretion and insulin sensitivity were essentially stable.. In high-risk relatives, beta-cell glucose sensitivity is impaired and is a strong predictor of diabetes progression. The time trajectories of plasma glucose are frequently biphasic, with a slow linear increase followed by a rapid surge, and are anticipated by a further deterioration of beta-cell glucose sensitivity. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Follow-Up Studies; Glucose Intolerance; Glucose Tolerance Test; Humans; Hyperglycemia; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Kaplan-Meier Estimate; Male; Models, Biological; Predictive Value of Tests; Risk Factors | 2010 |
Trends of earlier and later responses of C-peptide to oral glucose challenges with progression to type 1 diabetes in diabetes prevention trial-type 1 participants.
OBJECTIVE We studied the C-peptide response to oral glucose with progression to type 1 diabetes in Diabetes Prevention Trial-Type 1 (DPT-1) participants. RESEARCH DESIGN AND METHODS Among 504 DPT-1 participants <15 years of age, longitudinal analyses were performed in 36 progressors and 80 nonprogressors. Progressors had oral glucose tolerance tests (OGTTs) at baseline and every 6 months from 2.0 to 0.5 years before diagnosis; nonprogressors had OGTTs over similar intervals before their last visit. Sixty-six progressors and 192 nonprogressors were also studied proximal to and at diagnosis. RESULTS The 30-0 min C-peptide difference from OGTTs performed 2.0 years before diagnosis in progressors was lower than the 30-0 min C-peptide difference from OGTTs performed 2.0 years before the last visit in nonprogressors (P < 0.01) and remained lower over time. The 90-60 min C-peptide difference was positive at every OGTT before diagnosis in progressors, whereas it was negative at every OGTT before the last visit in nonprogressors (P < 0.01 at 2.0 years). The percentage whose peak C-peptide occurred at 120 min was higher in progressors at 2.0 years (P < 0.05); this persisted over time (P < 0.001 at 0.5 years). However, the peak C-peptide levels were only significantly lower at 0.5 years in progressors (P < 0.01). The timing of the peak C-peptide predicted type 1 diabetes (P < 0.001); peak C-peptide levels were less predictive (P < 0.05). CONCLUSIONS A decreased early C-peptide response to oral glucose and an increased later response occur at least 2 years before the diagnosis of type 1 diabetes. Topics: Adolescent; Area Under Curve; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Disease Progression; Female; Glucose; Glucose Tolerance Test; Humans; Longitudinal Studies; Male; Prediabetic State; Time Factors | 2010 |
The in vivo performance of bioartificial pancreas in bone marrow cavity: a case report of a spontaneous diabetic feline.
Recent studies reported that bone marrow cavity offers a widely distributed and well-vascularized microenvironment which is a considerable implantation site for bioartificial pancreas (BAP). In this study, the in vivo performance of BAPs in bone marrow was further demonstrated in a spontaneous diabetes animal. Mouse insulinoma cells encapsulating in agarose gel were enclosed in a calcium phosphate cement chamber to create a BAP. Ten BAPs were implanted into the femur bone marrow cavity of a diabetic feline. The preprandial blood glucose level, 2 h glucose curve, serum C-peptide level and physiological conditions of the recipient were recorded perioperatively. Results showed that the cat still suffered from hyperglycemia postoperatively. However, the physiological conditions of feline were improved with an increase of serum C-peptide level. The peak point of 2 h glucose curve decreased from 400 to 165-290 mg/dl. The efficiency of exogenous insulin extended from 2 to 10-14 h postoperatively which reveals that the implanted BAPs had partial function. This case report revealed that BAPs implanted in the bone marrow cavity for the spontaneous diabetic is effective. The implanted BAPs provided therapeutic benefit despite sustained hyperglycemia. Further study shall be considered to improve the outcomes of BAPs transplantation. Topics: Animals; Blood Glucose; Bone Marrow; C-Peptide; Cats; Cell Line, Tumor; Diabetes Mellitus, Type 1; Disease Models, Animal; Hyperglycemia; Insulin; Islets of Langerhans Transplantation; Mice; Pancreas, Artificial | 2010 |
Clinical and metabolic characteristics of patients with latent autoimmune diabetes in adults (LADA): absence of rapid beta-cell loss in patients with tight metabolic control.
The present study compared the clinical and metabolic characteristics of latent autoimmune diabetes in adults (LADA) with type 2 diabetes, as well as the residual beta-cell function and progression to insulin treatment, over a 2-year follow-up period, of antibody (Ab)-positive and Ab-negative patients who achieved tight glycaemic control (HbA(1c) 7.0+/-0.8% and 6.5+/-0.9%, respectively, at the time of entry into the study).. Glutamic acid decarboxylase antibodies (GADA) and/or islet cell antibodies (ICA) were detected in 10% of patients presenting with non-insulin-dependent diabetes. Around half of Ab-positive patients required insulin treatment during the follow-up. Ab-positive patients displayed lower stimulated C-peptide levels both at entry and during the follow-up compared with Ab-negative patients, although no significant decline in C-peptide levels was observed in either subgroup over two years. Nevertheless, Ab-positive patients progressed more frequently to insulin treatment, and stimulated C-peptide tended to decrease in LADA patients who subsequently required insulin, whereas it remained stable in those who were non-insulin-dependent. In those who progressed, the trend towards C-peptide decline persisted even after starting insulin treatment.. LADA patients demonstrate lower residual beta-cell function than do type 2 diabetes patients. However, those who achieve tight metabolic control do not present with a rapid decline in beta-cell function. Further studies are needed to determine the optimal treatment strategy in such patients. Topics: Adult; Age of Onset; Aged; Biomarkers; Blood Glucose; Body Mass Index; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Disease Progression; Female; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Prospective Studies | 2010 |
Dimorphic histopathology of long-standing childhood-onset diabetes.
Childhood diabetes is thought to usually result from autoimmune beta cell destruction (type 1A) with eventual total loss of beta cells. Analysis of C-peptide in children characterised at diabetes onset for autoantibodies shows heterogeneous preservation of insulin secretion in long-standing diabetes. The aim of this study was to characterise the pancreases of childhood-onset diabetes in order to define the pathological basis of this heterogeneity.. We evaluated 20 cadaveric organ donor pancreases of childhood-onset long-term patients for disease heterogeneity and obtained corresponding C-peptide measurements.. Pancreases from the majority of cadaveric donors contained only insulin-deficient islets (14 of 20). The remaining six patients (30%) had numerous insulin-positive cells within at least some islets, with two different histological patterns. Pattern A (which we would associate with type 1A diabetes) had lobular retention of areas with 'abnormal' beta cells producing the apoptosis inhibitor survivin and HLA class I. In pattern B, 100% of all islets contained normal-appearing but quantitatively reduced beta cells without survivin or HLA class I.. Our data demonstrate that C-peptide secretion in long-standing diabetic patients can be explained by two different patterns of beta cell survival,possibly reflecting different subsets of type 1 diabetes. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Histocompatibility Testing; HLA-DR Antigens; Humans; Hyperinsulinism; Insulin-Secreting Cells; Male; Middle Aged; Pancreas; Sex Characteristics; Tissue Donors | 2010 |
Comparison of insulin detemir and insulin glargine on glycemic variability in patients with type 1 and type 2 diabetes.
To compare the glycemic variability of insulin detemir and insulin glargine in type 1 and type 2 diabetic patients.. 15 type 1 and 14 type 2 diabetic patients receiving intensive insulin therapy with insulin glargine were enrolled. Before and after switching insulin glargine to insulin detemir, we assessed fasting glucose variability using the standard deviation (SD) and the coefficient of variance (CV) of self-monitored fasting blood sugar (FBS) levels.. The SD and CV values were significantly decreased in type 1 diabetes after switching the therapy, though there was no significant difference in type 2 diabetes. The frequency of hypoglycemia was decreased in type 1 diabetes and there was no change in type 2 diabetes. The changes of the CV value also showed significant positive correlation with fasting serum CPR levels in all patients and total insulin dose in type 1 diabetes. The changes of frequency of hypoglycemia showed significant positive correlation with total and basal insulin dose adjusted for body weight in type 1 diabetes.. The present study demonstrated lower within-subject variability of insulin detemir compared to insulin glargine, suggesting that the basal insulin replacement with insulin detemir may provide a useful therapeutic strategy for uncontrolled type 1 diabetes with high glucose variability. Topics: Adult; Aged; Blood Glucose; Blood Pressure; C-Peptide; C-Reactive Protein; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dose-Response Relationship, Drug; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin Detemir; Insulin Glargine; Insulin, Long-Acting; Insulin, Regular, Pork; Male; Middle Aged; Reproducibility of Results | 2010 |
Kidney-pancreas transplantation does not improve retinal arterial flow velocities in type 1 diabetic uremic patients.
Topics: Blood Flow Velocity; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Glycated Hemoglobin; Humans; Kidney Transplantation; Pancreas Transplantation; Prospective Studies; Proteinuria; Retinal Artery; Uremia | 2010 |
Predicting adult-onset autoimmune diabetes: clarity from complexity.
Topics: Adult; Age Distribution; Age of Onset; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Humans; Hypoglycemic Agents; Insulin; Major Histocompatibility Complex; Predictive Value of Tests | 2010 |
Inappropriate glucagon response after oral compared with isoglycemic intravenous glucose administration in patients with type 1 diabetes.
Hyperglucagonemia following oral glucose ingestion in patients with type 1 diabetes (and type 2 diabetes) has been claimed to result from impaired intraislet insulin inhibition of glucagon. We looked at plasma glucagon responses to the oral glucose tolerance test (OGTT) and isoglycemic intravenous glucose infusion (IIGI) in patients with type 1 diabetes. Nine patients without residual beta-cell function [age: 25 +/- 9 yr; body mass index (BMI): 24 +/- 2 kg/m(2); fasting plasma glucose (FPG): 9.5 +/- 2.1 mM; Hb A(1c): 8.4 +/- 1.2% (mean +/- SD)] and eight healthy subjects (age: 28 +/- 5 yr; BMI: 24 +/- 3 kg/m(2); FPG: 5.3 +/- 0.2 mM; Hb A(1c): 5.0 +/- 0.1%) were examined on two separate occasions: 4-h 50-g OGTT and IIGI. Isoglycemia during IIGIs was obtained using 53 +/- 5 g of glucose in patients with type 1 diabetes and 30 +/- 3 g in control subjects (P < 0.001), resulting in gastrointestinal-mediated glucose disposal [100% x (glucose(OGTT) - glucose(IIGI)/glucose(OGTT))] of -6 +/- 9 and 40 +/- 6% (P < 0.01), respectively. Equal glucagon suppression during the two glucose stimuli was observed in healthy subjects, whereas patients with type 1 diabetes exhibited less inhibition in response to OGTT compared with IIGI (AUC: 1,519 +/- 129 vs. 1,240 +/- 86 pM.4 h; P = 0.03). This difference was even more pronounced during the initial 40 min with paradoxical hypersecretion of glucagon during OGTT and suppression during IIGI (AUC: 37 +/- 13 vs. -33 +/- 16 pM.40 min; P = 0.02). These results suggest that the inappropriate glucagon response to glucose in patients with type 1 diabetes occurs as a consequence of the oral administration way, suggesting a role of the gastrointestinal tract, possibly via glucagonotropic signaling from gut hormones (e.g., glucose-dependent insulinotropic polypeptide), in type 1 diabetic hyperglucagonemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptides; Glucose; Glucose Tolerance Test; Humans; Infusions, Intravenous; Male; Young Adult | 2010 |
Treatment with insulin glargine (Lantus) increases the proliferative potency of the serum of patients with type-1 diabetes: a pilot study on MCF-7 breast cancer cells.
Insulin glargine (Lantus) stimulates growth of MCF-7 cells stronger than human insulin. We investigated if serum from diabetic patients treated with glargine versus human insulin may display a similar effect.. Pairs of serum samples from 31 C-peptide negative type-1 diabetic patients were investigated. In cross-over fashion, 23 patients were treated with glargine plus rapid-acting insulin analogues, and similar doses of human NPH and rapid-acting insulin. For comparison, eight patients were treated with insulin detemir (Levemir) and human NPH. MCF-7 cells were incubated with 10% serum and proliferation was assessed after 72 hours.. Serum containing insulin glargine was 1.11(95% CI 1.05-1.18) fold more mitogenic than human insulin-containing serum (p < 0.005); mitogenicity of serum containing detemir was 0.99(95% CI 0.98-1.02) fold that of human insulin-containing serum.. The serum of diabetic patients was slightly stronger mitogenic when using glargine as compared to human insulin or detemir for treatment. Topics: Breast Neoplasms; C-Peptide; Cell Line, Tumor; Cells; Chemotactic Factors; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Detemir; Insulin Glargine; Insulin, Long-Acting; Pilot Projects; Risk Factors | 2010 |
Effect of glucagon-like peptide-1 on alpha- and beta-cell function in C-peptide-negative type 1 diabetic patients.
The mechanism by which glucagon-like peptide-1 (GLP-1) suppresses glucagon secretion is uncertain, and it is not determined whether endogenous insulin is a necessary factor for this effect.. To characterize the alpha- and beta-cell responses to GLP-1 in type 1 diabetic patients without residual beta-cell function.. Nine type 1 diabetic patients, classified as C-peptide negative by a glucagon test, were clamped at plasma glucose of 20 mmol/liter for 90 min with arginine infusion at time 45 min and concomitant infusion of GLP-1 (1.2 pmol/kg x min) or saline.. Infusion with GLP-1 increased C-peptide concentration just above the detection limit of 33 pmol/liter in one patient, but C-peptide remained immeasurable in all other patients. In the eight remaining patients, total area under the curve of glucagon was significantly decreased with GLP-1 compared with saline: 485 +/- 72 vs. 760 +/- 97 pmol/liter x min (P < 0.001). In addition, GLP-1 decreased the arginine-stimulated glucagon release (incremental AUC of 103 +/- 21 and 137 +/- 16 pmol/liter x min, with GLP-1 and saline, respectively, P < 0.05).. In type 1 diabetic patients without endogenous insulin secretion, GLP-1 decreases the glucagon secretion as well as the arginine-induced glucagon response during hyperglycemia. GLP-1 induced endogenous insulin secretion in one of nine type 1 diabetic patients previously classified as being without endogenous insulin secretion. Topics: Arginine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Glucagon-Like Peptide 1; Glucagon-Secreting Cells; Humans; Hyperglycemia; Insulin-Secreting Cells; Serum Albumin | 2010 |
Proinsulin C-peptide prevents type-1 diabetes-induced decrease of renal Na+-K+-ATPase alpha1-subunit in rats.
C-peptide reduces renal damage in diabetic patients and experimental animal models. In vitro studies suggest that the renal effects of C-peptide may, in part, be explained by stimulation of Na(+)/K(+)-ATPase activity. However, the responses of Na(+)/K(+)-ATPase expression in the kidney of diabetic animals to C-peptide administration remain unclear. The aim of this study was to clarify the responses.. Type 1 diabetic rats were produced by injecting streptozotocin (STZ), and some of the rats were treated with either C-peptide or insulin by the aid of an osmotic pump for 1 week. The mRNA expression and immunohistochemical localization of Na(+)/K(+)-ATPase alpha1-, alpha2- and beta3-subunits were investigated in the kidney of these rats.. Na(+)/K(+)-ATPase alpha1-subunit was abundantly expressed in the medullary collecting ducts of control animals, but the expression was markedly decreased in the diabetic state with concomitant decrease in its mRNA expression. Similar decreases were observed in the insulin-treated diabetic rats, whereas in the C-peptide-treated diabetic rats, there was no reduction in the alpha1-expression. The beta3-subunit was expressed in podocytes and parietal cells in the glomeruli, vascular endothelial cells, and cortical collecting ducts, but lesser signals were observed in the proximal and distal tubules. However, the beta3-subunit did not appear to be affected by the diabetic state.. Diabetes selectively reduced Na(+)/K(+)-ATPase alpha1-subunit expression and abundance. Chronic administration of C-peptide prevented this decrease. This implies a role for C-peptide in the long-term regulation of Na(+)/K(+)-ATPase function. Topics: Analysis of Variance; Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Hypoglycemic Agents; Immunohistochemistry; Insulin; Kidney; Male; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; Sodium-Potassium-Exchanging ATPase | 2010 |
Generation of functional insulin-producing cells from human embryonic stem cells in vitro.
Human pancreatic islet transplantation at present is the preferred therapeutic option for type I diabetes treatment. However, this therapy is not widely utilized because of the severe shortage of donor islets. The capacity for self-renewal and differentiation of human embryonic stem (hES) cells makes them a potential new source for generation of functional pancreatic islet cells for treating type I diabetes mellitus. Here, we report a simple and effective protocol, carried out in a serum-free system, which could induce human ES cells to differentiate into functional insulin-producing cells. Activin A was first used in the initial stage to induce definitive endoderm lineage differentiation from human ES cells. And all-trans Retinoic Acid (RA) was then utilized to promote pancreatic differentiation. After maturation in the final induction stage with bFGF and Nicotinamide, the differentiated cells expressed islet specific markers. The secretion of insulin and C-peptide by these cells corresponded to the variations in glucose levels. Our method provides a promising in vitro differentiation model for studying the mechanisms of human pancreas development and illustrates the potential of using human ES cells for the treatment of type I diabetes mellitus. Topics: Animals; C-Peptide; Cell Culture Techniques; Cell Differentiation; Culture Media; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Mice | 2010 |
Detection of surreptitious administration of analog insulin to an 8-week-old infant.
An 8-week-old infant presented to the emergency department with lethargy, tachycardia, and a blood glucose concentration of 1.8 mmol/L. After admission, hypoglycemia recurred on 3 additional occasions. Initial urinalysis results were negative for ketones, and the results of additional laboratory tests did not support the diagnosis of cortisol or growth hormone deficiency, oral hypoglycemic ingestion, or an inborn error of metabolism. Difficulty restoring and maintaining glucose concentrations along with a transient response to glucagon during 1 hypoglycemic episode suggested hyperinsulinism. In 1 hypoglycemic episode, elevated insulin and low C-peptide concentrations suggested exogenous insulin administration, but 2 subsequent blood samples obtained during hypoglycemia contained appropriately decreased concentrations of insulin. The insulin immunoassay initially used in this case (Roche ElecSys/cobas [Roche Diagnostics, Indianapolis, IN]) was insensitive to insulin analogs. Two additional immunoassays, 1 with intermediate (Immulite [Siemens, Deerfield, IL]) and 1 with broad (radioimmunoassay [Millipore, Inc, Billerica, MA]) reactivity to insulin analogs were used to characterize insulin in each of the critical blood samples. Samples obtained during hypoglycemia displayed a graded reactivity similar to that observed in type 1 diabetic patients prescribed insulin analogs, whereas a sample obtained from the patient and a control subject during euglycemia showed equal reactivity among the 3 assays. These data suggested administration of insulin analog to the child, and further characterization of insulin by using tandem mass spectrometry confirmed the presence of Humalog. The child was subsequently placed in foster care with no further recurrence of hypoglycemia. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diagnosis, Differential; Emergency Service, Hospital; Female; Glucagon; Humans; Hyperinsulinism; Hypoglycemia; Hypoglycemic Agents; Infant; Insulin; Insulin Aspart; Male; Munchausen Syndrome by Proxy; Pregnancy; Pregnancy in Diabetics; Recurrence | 2010 |
Human islet cell implants in a nude rat model of diabetes survive better in omentum than in liver with a positive influence of beta cell number and purity.
Intraportal human islet cell grafts do not consistently and sustainably induce insulin-independency in type 1 diabetic patients. The reasons for losses in donor cells are difficult to assess in patients. This study in streptozotocin-diabetic nude rats examines whether outcome is better in an extra-hepatic site such as omentum.. Intraportal and omental implants of human islet cell grafts with the same beta cell number were followed for function and cellular composition over 5 weeks. Their outcome was also compared with that of rat islet cell grafts with similar beta cell numbers but higher purity.. While all intraportal recipients of rat islet cell grafts were normoglycaemic until post-transplant (PT) week 5, none was with human islet cell grafts; loss of human implants was associated with early infiltration of natural killer and CD45R-positive cells. Human islet cell implants in omentum achieved plasma human C-peptide positivity and normoglycaemia in, respectively, nine of 13 and five of 13 recipients until PT week 5; failures were not associated with inflammatory infiltrates but with lower beta cell numbers and purity of the grafts. Observations in human and rat islet cell implants in the omentum suggest that a delayed revascularisation can interfere with their metabolic outcome. Irrespective of normalisation, human omental implants presented beta cell aggregates adjacent to alpha cells and duct cells.. In nude rats, human islet cell implants survive better in omentum than in liver, with positive influences of the number and purity of implanted beta cells. These observations can guide studies in patients. Topics: Analysis of Variance; Animals; C-Peptide; Cell Survival; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Liver; Male; Omentum; Rats; Rats, Nude; Rats, Wistar; Transplantation, Heterologous | 2010 |
Association of adiponectin, interleukin (IL)-1ra, inducible protein 10, IL-6 and number of islet autoantibodies with progression patterns of type 1 diabetes the first year after diagnosis.
The progression of type 1 diabetes after diagnosis is poorly understood. Our aim was to assess the relation of disease progression of juvenile-onset type 1 diabetes, determined by preserved beta cell function the first year after diagnosis, with systemic cytokine concentrations and number of autoantibodies. Juvenile patients (n = 227) had a meal-stimulated C-peptide test 1 and 6 months after diagnosis. On the basis of the C-peptide course for the duration of 1-6 months, four progression groups were defined: patients with persistently low beta cell function ('stable-low'), rapid progressers, slow progressers and remitters. Serum concentrations of adiponectin, interleukin (IL)-1ra, inducible protein 10 (IP-10), IL-6 and glutamic acid decarboxylase (GAD), IA-2A and islet-cell antibodies (ICA) were measured at 1, 6 and 12 months. We found that adiponectin concentrations at 1 month predicted disease progression at 6 months (P = 0·04). Patients with low adiponectin had a higher probability of becoming remitters than rapid progressers, odds ratio 3·1 (1·3-7·6). At 6 and 12 months, adiponectin differed significantly between the groups, with highest concentrations among stable-low and rapid progressers patients (P = 0·03 and P = 0·006). IL-1ra, IP-10 and IL-6 did not differ between the groups at any time-point. The number of autoantibodies differed significantly between the groups at 1 month (P = 0·04), where rapid progressers had the largest number. There was no difference between the groups in human leucocyte antigen-associated risk. We define progression patterns distinguishing patients diagnosed with low beta cell function from those with rapid decline, slow decline or actual increase in beta cell function, pointing to different mechanisms of disease progression. We find that adiponectin concentration at 1 month predicts, and at 6 and 12 months associates with, distinct progression patterns. Topics: Adiponectin; Adolescent; Autoantibodies; C-Peptide; Chemokine CXCL10; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Humans; Infant; Interleukin 1 Receptor Antagonist Protein; Interleukin-6; Male; Predictive Value of Tests; Prospective Studies; Time Factors | 2010 |
Improved second phase insulin secretion and preserved insulin sensitivity after islet transplantation.
Topics: Awareness; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Middle Aged; Monitoring, Physiologic; Transplantation, Homologous; Treatment Outcome | 2010 |
Bilateral diabetic papillopathy and metabolic control.
The pathogenesis of diabetic papillopathy largely is unknown, but case reports suggest that it may follow rapidly improved metabolic control. The present study was designed to investigate this hypothesis.. Retrospective case-control study.. Two thousand sixty-six patients with type 1 diabetes.. Review of clinical, photographic, and clinical chemistry records from a large diabetology and ophthalmology unit between 2001 and 2008.. Simultaneous, bilateral diabetic papillopathy.. The mean follow-up was 4.9 years. During 10,020 patient-years of observation, bilateral diabetic papillopathy developed in 5 patients. During the year preceding this incident, all 5 patients had experienced a decrease in glycosylated hemoglobin A₁(c) (HbA₁(C)) at a maximum rate of -2.5 (mean) percentage points per quarter year, which was significantly different from the changes in HbA₁(C) observed in the remainder of the study population (P<0.001). Photographs recorded before the onset of bilateral diabetic papillopathy showed that all 5 patients had small cup-to-disc diameter ratios in both eyes (P<0.001).. Diabetic papillopathy was associated markedly with a drastic recent reduction in glycemia and a small cup-to-disc diameter ratio. This supports the hypothesis that diabetic papillopathy may be an early worsening phenomenon occurring in anatomically predisposed patients in response to a recent rapid decrease in glycemia.. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Female; Follow-Up Studies; Functional Laterality; Glycated Hemoglobin; Humans; Male; Middle Aged; Optic Disk; Papilledema; Retrospective Studies; Risk Factors; Young Adult | 2010 |
Inconsistent formation and nonfunction of insulin-positive cells from pancreatic endoderm derived from human embryonic stem cells in athymic nude rats.
Embryonic stem cell therapy has been proposed as a therapeutic strategy to restore β-cell mass and function in T1DM. Recently, a group from Novocell (now ViaCyte) reported successful development of glucose-responsive islet-like structures after implantation of pancreatic endoderm (PE) derived from human embryonic stem cells (hESC) into immune-deficient mice. Our objective was to determine whether implantation of hESC-derived pancreatic endoderm from Novocell into athymic nude rats results in development of viable glucose-responsive pancreatic endocrine tissue. Athymic nude rats were implanted with PE derived from hESC either via implantation into the epididymal fat pads or by subcutaneous implantation into TheraCyte encapsulation devices for 20 wk. Blood glucose, weight, and human insulin/C-peptide secretion were monitored by weekly blood draws. Graft β-cell function was assessed by a glucose tolerance test, and graft morphology was assessed by immunohistochemistry and immunofluorescence. At 20 wk postimplantation, epididymal fat-implanted PE progressed to develop islet-like structures in 50% of implants, with a mean β-cell fractional area of 0.8 ± 0.3%. Human C-peptide and insulin were detectable, but at very low levels (C-peptide = 50 ± 26 pmol/l and insulin = 15 ± 7 pmol/l); however, there was no increase in human C-peptide/insulin levels after glucose challenge. There was no development of viable pancreatic tissue or meaningful secretory function when human PE was implanted in the TheraCyte encapsulation devices. These data confirm that islet-like structures develop from hESC differentiated to PE by the protocol developed by NovoCell. However, the extent of endocrine cell formation and secretory function is not yet sufficient to be clinically relevant. Topics: Animals; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Embryonic Stem Cells; Endoderm; Fluorescent Antibody Technique, Direct; Glucose Clamp Technique; Humans; Immunohistochemistry; Insulin; Insulin-Secreting Cells; Longitudinal Studies; Male; Rats; Rats, Nude; Rats, Sprague-Dawley; Specific Pathogen-Free Organisms | 2010 |
Glucose excursions between states of glycemia with progression to type 1 diabetes in the diabetes prevention trial-type 1 (DPT-1).
We characterized fluctuations between states of glycemia in progressors to type 1 diabetes and studied whether those fluctuations are related to the early C-peptide response to oral glucose.. Oral glucose tolerance tests (OGTTs) from differing states of glycemia were compared within individuals for glucose and C-peptide. Dysglycemic OGTTs (DYSOGTTs) were compared with normal OGTTs (NLOGTT), while transient diabetic OGTTs (TDOGTTs) were compared with subsequent nondiabetic OGTTs and with OGTTs performed at diagnosis.. Of 135 progressors with four or more OGTTs, 30 (22%) went from NLOGTTs to DYSOGTTs at least twice. Area under the curve (AUC) glucose values from the second NLOGTT were higher (P < 0.001) than values from the first NLOGTT. Among 98 progressors whose DYSOGTTs and NLOGTTs were synchronized for the time before diagnosis, despite higher glucose levels (P < 0.01 at all time points) in the DYSOGTTs, 30- to 0-min C-peptide difference values changed little. Likewise, 30- to 0-min C-peptide difference values did not differ between TDOGTTs and subsequent (within 3 months) nondiabetic OGTTs in 55 progressors. In contrast, as glucose levels increased overall from the first to last OGTTs before diagnosis (P < 0.001 at every time point, n = 207), 30- to 0-min C-peptide difference values decreased (P < 0.001).. Glucose levels fluctuate widely as they gradually increase overall with progression to type 1 diabetes. As glucose levels increase, the early C-peptide response declines. In contrast, glucose fluctuations are not related to the early C-peptide response. This suggests that changes in insulin sensitivity underlie the glucose fluctuations. Topics: Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Glucose Tolerance Test; Humans; Prediabetic State; Reference Values | 2010 |
Changes in GAD65Ab-specific antiidiotypic antibody levels correlate with changes in C-peptide levels and progression to islet cell autoimmunity.
The previously reported absence of 65-kDa glutamate decarboxylase antibody (GAD65Ab)-specific antiidiotypic antibodies (anti-Id) in type 1 diabetes (T1D) patients at clinical onset could be due to an inability to mount an antibody response to GAD65Ab or a longitudinal decline in anti-Id levels.. We investigated anti-Id levels in longitudinal samples obtained from T1D patients (n = 41) (clinical diagnosis - 12 months), and latent autoimmune diabetes in adults (LADA) patients (n = 32) who received alum-formulated human recombinant GAD65 (baseline - 12 months). We also determined anti-Id levels in a small cohort of Type 2 diabetes patients during their development of autoimmune T cell responses.. At clinical onset T1D patients presented no or low anti-Id levels. However, 22/41 T1D patients showed ≥50% increase in GAD65Ab-specific anti-Id levels during follow-up; peaking at 3 (n = 1), 6 (n = 10), 9 (n = 10), or 12 (n = 1) months. Increasing anti-Id levels marked patients who experienced a temporary increase in C-peptide levels. Anti-Id levels correlated significantly with glycated hemoglobin and C-peptide levels at 6 and 9 months (P values ranged from <0.001 to <0.05). In LADA patients receiving placebo, anti-Id levels declined in seven of nine patients, whereas four of five patients receiving 20 μg alum-formulated human recombinant GAD65 showed increasing anti-Id levels. Changes in anti-Id and C-peptide levels closely correlated (P < 0.0001). The significant decline in anti-Id levels (P = 0.03) in T2D patients developing T cell autoimmune responses supports our hypothesis that declining anti-Id levels are associated with developing islet autoimmunity.. The close association between GAD65Ab-specific anti-Id levels and β-cell function may provide a novel marker for the progression of autoimmune diabetes. Topics: Adolescent; Analysis of Variance; Antibodies, Anti-Idiotypic; Autoimmunity; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Female; Glutamate Decarboxylase; Humans; Infant; Islets of Langerhans; Male; Prospective Studies | 2010 |
[GADA persistence and detectable C peptide in patients with long standing diabetes mellitus type 1].
The aim of this study was to evaluate if GADA+ and detectable CP had any influence in other autoimmune diseases, glycemic control, and risks of retinopathy in diabetes mellitus type 1 (T1DM) lasting longer than 3 years of duration.. Fifty T1DM subjects were interviewed, performed fundoscopic examination, and measured CP before and after glucagon, HbA1C, and GADA.. GADA+ (n = 17) had a higher frequency of other autoimmune diseases when compared to GADA (p = 0.02). Detectable CP was also associated with a higher prevalence of these diseases (p = 0.03), although, retinopathy was not influenced by either one. Detectable CP had no influence in the glycemic control (mean HbA1C) (p = 0.28). However, insulin daily doses were lower in this group (0.62 vs. 0.91 U/kg/day; p = 0.004).. Although not recommend as a marker of other autoimmune diseases, GADA+ seems to be not only a pancreatic autoimmunity signal. Detectable CP may also have some promising influence in detecting these diseases. Neither influenced the presence of retinopathy, but insulin daily requirements were smaller when CP was present. Topics: Adult; Autoantibodies; Autoimmune Diseases; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Glucagon; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male | 2010 |
Residual insulin production and pancreatic ß-cell turnover after 50 years of diabetes: Joslin Medalist Study.
To evaluate the extent of pancreatic β-cell function in a large number of insulin-dependent diabetic patients with a disease duration of 50 years or longer (Medalists).. Characterization of clinical and biochemical parameters and β-cell function of 411 Medalists with correlation with postmortem morphologic findings of 9 Medalists.. The Medalist cohort, with a mean ± SD disease duration and age of 56.2 ± 5.8 and 67.2 ± 7.5 years, respectively, has a clinical phenotype similar to type 1 diabetes (type 1 diabetes): mean ± SD onset at 11.0 ± 6.4 years, BMI at 26.0 ± 5.1 kg/m(2), insulin dose of 0.46 ± 0.2 u/kg, ∼94% positive for DR3 and/or DR4, and 29.5% positive for either IA2 or glutamic acid decarboxylase (GAD) autoantibodies. Random serum C-peptide levels showed that more than 67.4% of the participants had levels in the minimal (0.03-0.2 nmol/l) or sustained range (≥ 0.2 nmol/l). Parameters associated with higher random C-peptide were lower hemoglobin A1C, older age of onset, higher frequency of HLA DR3 genotype, and responsiveness to a mixed-meal tolerance test (MMTT). Over half of the Medalists with fasting C-peptide > 0.17 nmol/l responded in MMTT by a twofold or greater rise over the course of the test compared to fasting. Postmortem examination of pancreases from nine Medalists showed that all had insulin+ β-cells with some positive for TUNEL staining, indicating apoptosis.. Demonstration of persistence and function of insulin-producing pancreatic cells suggests the possibility of a steady state of turnover in which stimuli to enhance endogenous β cells could be a viable therapeutic approach in a significant number of patients with type 1 diabetes, even for those with chronic duration. Topics: Aged; Awards and Prizes; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Female; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Insulin; Insulin-Secreting Cells; Male; Middle Aged; Numismatics; Phenotype; Time Factors; Tissue and Organ Procurement | 2010 |
[Evaluation of preserved insulin secretion in children and adolescents with type 1 diabetes].
The pathogenesis of type 1 diabetes is connected with immune-mediated beta-cell destruction leading to insulin deficiency. The majority of patients will become completely incapable of insulin secretion within a few years, however, some individuals will have persistent beta-cell function years after the diagnosis of diabetes. Despite clinical symptoms of insulin deficiency, residual beta-cell secretion can modify the clinical course and can be an independent factor influencing the delay of development of chronic diabetic complications. The aim of the study was to compare a 10-year clinical course in children with type 1 diabetes with and without preserved beta-cell secretion.. 72 children and adolescents with diabetes lasting for minimum 10 years and available biological material to c-peptide evaluation (3-4 years and 10 years from the onset of diabetes) were chosen from 768 children with type 1 diabetes. We assessed fasting c-peptide and recruited 23 out of 72 patients whose concentration of c-peptide was below or over 0.23 ng/ml at all time points (this cut point derives from the definition of preserved beta-cell function according to DCCT). Afterwards we divided children into two subgroups: A (n=13) - without insulin secretion and B (n=10) - with preserved beta-cell function during 10 years of observation. We assessed markers of beta-cell autoimmunity (ICA, GADA, IA2, IAA) in the examined groups. Insulin requirement and concentration of glycated hemoglobin (assessed as the year mean from four measurements in each year) were compared between group A and B.. The age at onset of diabetes in children from both examined groups was similar. All children from group B and 12/13 from group A were positive for at least one type of the screened autoantibodies. There was no difference in insulin requirement between the groups (p=0.6). The level of glycated hemoglobin was significantly lower in group B during a 10-year observational period (p=0.04).. Repeated measures of c-peptide can enable us to define two groups of patients with immune-mediated diabetes with different levels of disease and metabolic control. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Male | 2010 |
[Optimization of monogenic diabetes screening programme--initial report on recruitment efficacy of the TEAM project].
Due to the lack of precise diagnostic criteria, current search strategy for monogenic diabetes is predominantly based on atypical clinical course of diabetes and intuition of the attending physician. Yet another issue is the common view that monogenic diabetes is rare. It discourages from performing deepened diagnostics and makes it difficult to gain experience necessary to select appropriate patients for genetic examination.. Estimating the true incidence of patients with a high probability of monogenic background of the disease and compare their search strategies based on clinical practice or structured databases.. The authors compared the current strategy of selecting candidates for screening with a directed search strategy based on immunologic (lack of islet autoantibodies), functional (presence or complete lack of c-peptide at onset and follow-up) and familial (dominant pattern of inheritance) criteria. The number of patients selected for the screening was chosen as efficacy measure selected among 1281 diabetic patients diagnosed and treated between 1983-2009.. Screening based on clinical assessment yielded 37 patients (2.9%) chosen for genetic screening. Criteria used by the physicians were based on up-to-date guidelines and unusual clinical course. Active search of the database according to predefined criteria resulted in selecting: 121 patients (9.4%) with likely monogenic background of diabetes (71 - lack of autoantibodies, 8 - normal C-peptide, 6 - lack of both c-peptide and autoantibodies, 36 - diabetes in at least one parent). The difference in screening efficacy was statistically significant (p <0.0001).. Periodic reevaluation of patients' data allows a significant increase in the number of candidates subjected to genetic screening and potentially achieving beneficial therapeutic effects by means of pharmacogenetics. Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Genetic Testing; Humans; Incidence; Insulin-Secreting Cells; Mass Screening; Patient Selection | 2010 |
Outcomes after simultaneous pancreas and kidney transplantation and the discriminative ability of the C-peptide measurement pretransplant among type 1 and type 2 diabetes mellitus.
Earlier studies reporting outcomes after pancreas transplantation have included a combination of C-peptide cutoffs and clinical criteria to classify type 2 diabetes mellitus (T2DM). However, because the kidney is the major site for C-peptide catabolism, C-peptide is unreliable to discriminate the type of diabetes in patients with kidney disease.. To improve the discriminative power and better classify the type of diabetes, we used a composite definition to identify T2DM: presence of C-peptide, negative glutamic acid decarboxylase antibody, absence of diabetic ketoacidosis, and use of oral hypoglycemics. Additionally among T2DM patients with end-stage renal disease (ESRD), body mass index of <30 kg/m(2) and use of <1 u/kg of insulin per day were selection criteria for suitablity for simultaneous pancreas and kidney transplantation (SPKT). We compared graft and patient survival between T1DM and T2DM after SPKT.. Our study cohort consisted of 80 patients, 10 of whom were assigned as T2DM based on our study criteria. Approximately 15% of patients with T1DM had detectable C-peptide. Cox regression survival analyses found no significant differences in allograft (pancreas and kidney) or patient survival between the 2 groups. The mean creatinine clearance at 1 year estimated by the modification of Diet in Renal Disease (MDRD) equation was not significantly different between the 2 groups. Among those with 1 year of follow-up, all patients with T2DM had glycosylate hemoglobin of <6.0 at 1 year versus 92% of those with T1DM.. SPKT should be considered in the therapeutic armamentarium for renal replacement in selected patients with T2DM and ESRD. Use of C-peptide measurements for ESRD patients can be misleading as the sole criterion to determine the type of diabetes. Topics: Adult; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Retinopathy; Female; Follow-Up Studies; Glycated Hemoglobin; Graft Rejection; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Retrospective Studies; Survival Analysis; Tissue Donors | 2010 |
The diagnostic value of zinc transporter 8 autoantibody (ZnT8A) for type 1 diabetes in Chinese.
Zinc transporter-8 (ZnT8) was recently identified as a novel autoantigen in human type 1 diabetes (T1D). Autoantibody to ZnT8 (ZnT8A) was detected in up to 80% of patients with new-onset T1D and 26% of patients with T1D otherwise classified as negative on the basis of existing markers. As no data of ZnT8A in Chinese have been reported, we aim to evaluate the utility of ZnT8A for diagnosis of autoimmune T1D in Chinese relative to other autoantibody markers.. Radioligand binding assays were performed on 539 T1D sera using human ZnT8 carboxyterminal 325Arg construct or a dimer incorporating 325Arg and 325Trp alongside antibodies to glutamic acid decarboxylase (GADA) or insulinoma-associated protein 2 (IA-2A). The antigenic specificity was analysed in the context of clinical characteristics of the patients.. ZnT8A were present in 24.1% (130 of 539) of patients with T1D versus 1.8% (10 of 555; P < 0.001) in type 2 diabetes. At diagnosis, ZnT8A and IA-2A were less prevalent in Chinese subjects with T1D than in Caucasian populations (both P < 0.001) but similar to Japanese. The diagnostic sensitivity of combined GADA, IA-2A and ZnT8A measurements reached 65.5% with ZnT8A detected in 13.5% (29 of 215) of GADA and/or IA-2A-negative subjects. ZnT8A prevalence was lower in older and fatter patients. ZnT8A+ alone patients were distinguished from Ab- ones (P < 0.05-0.001) on the basis of higher insulin requirement and lower systolic blood pressure level.. ZnT8A is an independent marker for T1D in Chinese and combined with GADA and IA-2A enhances diagnostic sensitivity. ZnT8A may be associated with different clinical phenotypes than GADA or IA-2A. Topics: Adolescent; Adult; Aged; Asian People; Autoantibodies; Biomarkers; C-Peptide; Cation Transport Proteins; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Infant; Insulin; Male; Middle Aged; Receptor-Like Protein Tyrosine Phosphatases, Class 8; Young Adult; Zinc Transporter 8 | 2010 |
[C-peptide].
Topics: Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Factitious Disorders; Humans; Hypoglycemia; Insulin Antibodies; Insulin Resistance; Insulin-Secreting Cells | 2010 |
Long-term follow-up of patients with type 1 diabetes transplanted with neonatal pig islets.
Pancreas transplantation is an option to achieve better metabolic control and decrease chronic complications in patients with diabetes. Xenotransplantation becomes an important alternative. In this study, we show the clinical outcome of patients with type 1 diabetes transplanted with neonatal pig islets without immunosuppression. In a longitudinal study of 23 patients with type 1 diabetes, who received porcine islets between 2000 and 2004, we registered demographic and clinical characteristics every 3 months and chronic complications evaluation yearly. Porcine C-peptide was measured in urine samples under basal conditions and after stimulation with l-arginine. More than 50% were female, median current age was 20·8 years, median diabetes duration at transplantation 5·5 years, median current diabetes duration 11 years and median time post-transplantation 5·7 years. Their media of glycosylated haemoglobin reduced significantly after the first transplantation. Insulin doses remain with a reduction greater than 33% in more than 50% of the patients. Before transplantation, 14 of the 21 patients presented mild chronic complications and currently only two patients presented these complications. Porcine C-peptide was present in all urine samples under basal conditions and increased post-stimulation with l-arginine. These patients achieved an excellent metabolic control after the first transplantation. This could explain, as well as the remaining function of transplanted cells, the low frequency of chronic complications compared to patients with similar diabetes duration and age. Topics: Adolescent; Animals; Animals, Newborn; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Disease Progression; Disease-Free Survival; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Islets of Langerhans Transplantation; Male; Swine; Time Factors; Transplantation, Heterologous; Young Adult | 2010 |
Type 1 diabetes and LADA--occurrence of HLA-DRB1 *03 and DRB1 *04 alleles in two age different groups of diabetics.
Type 1 Diabetes Mellitus (T1D) with an onset in adulthood and Late Autoimmune Diabetes of Adults (LADA) are connected with autoimmune insulitis (associated with islet cell autoantibodies) and the specific high-risk HLA class II genotype. The study was aimed at analyzing time and clinical characteristics of the diabetics with an onset of the disease after 35 y. (T1D and LADA). Main target of the study was to assess possible role of the old age onset and compare it with diabetics with the onset in the middle age (incl. analyzing HLA-DRB1 genotype). In the study, we included 103 diabetics with an onset of autoimmune diabetes at 35+ y. who were hospitalized and afterwards long-term observed in the diabetological outpatient department. 46 men and 57 women of the average age 65.7 +/- 13.8 y. (range 35-93 y.) were out of this number. 41 were assessed as the T1D patients and 61 as the LADA ones. As a control group we used 99 healthy individuals. Patients of the T1D subgroup developed diabetes in the age of 50.8 +/- 15.1 y. and of the LADA subgroup in the age of 52.6 +/- 12.8 y. Its duration in the time of this study was 10.7 +/- 11.6 y.; respectively 5.3 +/- 7.1 y. Fasting and postprandial C-peptide levels were statistically higher (p < 0.01) in the LADA subgroup vs. T1D. Obesity 1st and 2nd grade were present together only in 12.6%. BMI was not statistically significantly different between both groups. We found in our diabetic patients the predisposition alleles HLA-DRB1*03, HLA-DRB1*04 and particularly their combination. The occurrence of these HLA alleles is significantly higher in T1D patients in comparison to control groups (p = 0.01, OR = 4.0). In our study, the occurrence of the susceptible HLA-DRB1*03 and HLA-DRB1*04 alleles in T1D patients is higher than in LADA. The presence of these alleles identifies patients of high risk and requirement of insulin therapy. Since risk alleles are similarly present in middle and old age, environmental factors probably play similar role in these onsets of autoimmune diabetes. Topics: Adult; Age of Onset; Aged; Aged, 80 and over; Aging; Alleles; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Glycated Hemoglobin; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Polymerase Chain Reaction; Predictive Value of Tests; Risk | 2010 |
N-terminal segment of proinsulin C-peptide active in insulin interaction/desaggregation.
Evidence has emerged that proinsulin C-peptide has at least three types of functional interactions in addition to its role during synthesis and secretion of insulin. Thus, C-peptide has been shown (i) to bind to cell membranes triggering G-protein-mediated intracellular signaling; (ii) to be internalized into cells and nuclei promoting transcription of rRNA and expression of particular genes; and (iii) to interact with peptides, including insulin, causing desaggregation of insulin oligomers like a chaperone, and with itself, causing homo-oligomers potentially capable of forming aggregates and deposits. In this work, we studied the insulin-C-peptide interactions by monitoring desaggregation and binding effects of C-peptide fragments on insulin. We find that the N-terminal segment of C-peptide harbors an interaction with insulin and that Glu11 appears to play a role in this action. We conclude that C-peptide fragments with this residue can mimic C-peptide in biophysical interactions with insulin, and that the insulin-interacting and membrane-interacting effects of C-peptide are distinct, ascribable to separate C-peptide segments, N- and C-terminally, respectively. The findings may have relevance to peptide effects in diabetic and healthy states. Topics: Amino Acid Sequence; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamic Acid; Humans; Insulin; Molecular Sequence Data | 2010 |
Comment on: Keenan et al. (2010) residual insulin production and pancreatic ß-Cell turnover after 50 years of diabetes: Joslin Medalist Study. Diabetes 2010;59:2846-2853.
Topics: C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Eating; Homeostasis; Humans; Insulin; Insulin-Secreting Cells | 2010 |
Simultaneous kidney-pancreas transplantation for end-stage renal disease patients with insulin-dependent diabetes and detectable C-peptide.
There is controversy regarding the place of simultaneous pancreas-kidney (SPK) transplantation in end-stage renal disease (ESRD) patients with insulin-dependent diabetes mellitus (IDDM) and detectable c-peptide. We sought to compare outcomes of recipients with and without pretransplantation c-peptide.. This retrospective single-center review included consecutive primary SPK transplantations performed between September 2007 and May 2010. Demographic characteristics and outcomes were compared between recipients with and without pretransplantation c-peptide.. Seven of 25 (28%) consecutive SPK transplant recipients with a diagnosis of IDDM and ESRD had detectable c-peptide prior to transplantation. The mean c-peptide level was 6.3 ± 6.1 ng/mL. For those recipients with and without c-peptide, mean age at diagnosis of IDDM (12.4 ± 7.8 vs 17.1 ± 6.6 years; P = not significant [NS]), duration of IDDM prior to transplantation (30 ± 10 vs 23 ± 9 years; P = NS), and body mass index (25.9 ± 4.5 vs 26.7 ± 4.5 kg/m(2); P = NS) were equivalent between the groups. With a median follow-up of 17 months (range, 3-35 months) there was 1 graft loss (due to cardiovascular death) among the 25 patients. At the most recent follow-up, for recipients with and without c-peptide, both the mean serum creatinine (1.3 ± 0.6 vs 1.0 ± 0.2 ng/mL; P = NS) and the mean HbA1c level (5.3 ± 0.4 vs 5.3 ± 0.5; P = NS) were equivalent between the groups.. For nonobese ESRD patients diagnosed with IDDM at a young age, the presence of detectable c-peptide should not influence the decision to proceed with SPK transplantation. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Pancreas Transplantation; Retrospective Studies | 2010 |
Clinical presentation and autoimmune characteristics of very young children at the onset of type 1 diabetes mellitus.
The aim of our study was to identify factors that are related to a more aggressive beta-cell destruction in children at presentation of type 1 diabetes mellitus (T1D). We analyzed age, HbAlc, pH, bicarbonate, IAA, IA2, GADA, C peptide of 290 consecutive patients with T1D at onset. Seventy-three (25.2%) were younger than 4 years; 217 (74.8%) were aged 4-18 years. Younger patients had lower C peptide, pH and bicarbonate than older ones. Age at T1D onset was negatively related to IAA titers (r: -0.3404, p < 0.001), positively related to IA2 titers (r: 0.1249, p: 0.03) and to C peptide (r: 0.42, p: < 0.001). Multivariable linear regression showed that C peptide was negatively related to HbA1c and positively related to age, pH at admission and IAA titers. T1D in very young children is characterized by a more extensive beta-cell destruction, and younger age at onset is related to a more severe decompensation. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Infant; Infant, Newborn; Insulin Antibodies; Insulin-Secreting Cells; Linear Models; Male | 2010 |
German new onset diabetes in the young incident cohort study: DiMelli study design and first-year results.
Diabetes incidence in childhood and youth is increasing worldwide, including autoimmune and non-autoimmune cases. Recent findings suggest that there is a larger than expected proportion of type 2 diabetes in youth, and potential cases of intermediate diabetes phenotypes. Most pediatric diabetes registries focus on type 1 diabetes. Also, there is an absence of reliable data on type 2 diabetes incidence in youth.. The DiMelli study aims to establish a diabetes incidence cohort registry of patients in Germany, diagnosed with diabetes mellitus before age 20 years. It will be used to characterize diabetes phenotypes by immunologic, metabolic, and genetic markers. DiMelli will assess the contribution of obesity and socio-demographic factors to the development of diabetes in childhood and youth.. Recruitment of patients started in 2009, and is expected to continue at a rate of 250 patients per year.. 84% of the 216 patients recruited within the first year were positive for multiple islet autoantibodies, 12% for one islet autoantibody, and 4% were islet autoantibody-negative. Patients with multiple islet autoantibodies were younger and had lower fasting C-peptide levels, compared to islet autoantibody-negative patients (median age 10.0 vs. 14.1 years, p < 0.01).. Results from the first year of the study show that DiMelli will help to reveal new knowledge on the etiology of diabetes, and the contribution of genetic predisposition and environmental risk factors to the different types of diabetes. Topics: Adolescent; Age of Onset; C-Peptide; Child; Cohort Studies; Demography; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Germany; Humans; Incidence; Male; Registries; Research Design; White People; Young Adult | 2010 |
Type 1 diabetes and idiopathic retroperitoneal fibrosis: case report.
Retroperitoneal fibrosis is characterized by the presence of a retroperitoneal tissue, consisting of chronic inflammation and marked fibrosis, which entraps the retroperitoneal organs. In two-thirds of cases, the retroperitoneal fibrosis is idiopathic. The pathogenic mechanism is not clearly identified. We report a case of idiopathic retroperitoneal fibrosis associated with type 1 diabetes mellitus. A 61-year-old woman with C peptide negative insulindependent diabetes developed retroperitoneal fibrosis revealed by bilateral hydronephrosis. Anti-GAD 65 antibodies were positive. There were no signs of autoimmune pancreatitis: no steatorrhea, normal IgG4 isotype levels, and absence of pancreas morphological abnormalities. Topics: Anti-Inflammatory Agents; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Hydronephrosis; Middle Aged; Retroperitoneal Fibrosis; Retroperitoneal Space; Steroids; Tomography, X-Ray Computed; Ureter | 2009 |
Heterogeneity of patients with latent autoimmune diabetes in adults: linkage to autoimmunity is apparent only in those with perceived need for insulin treatment: results from the Nord-Trøndelag Health (HUNT) study.
Subjects with the diagnosis of latent autoimmune diabetes in adults (LADA) are more prone to need insulin treatment than those with type 2 diabetes. However, not all patients with LADA develop the need for insulin treatment, indicating the heterogeneity of LADA. We investigated this heterogeneity by comparing phenotypes of LADA with and without perceived need for insulin treatment (data obtained at times when diagnosis of LADA was not investigated) and also compared LADA and type 2 diabetes phenotypes.. We used data from the all population-based Nord-Trøndelag Health study (n = 64,931), performed in 1995-1997. Data were assembled for individuals with LADA (n = 106) and type 2 diabetes (n = 943).. In the comparison of individuals with LADA both with and without the need for insulin, insulin-treated subjects had higher titers of GAD antibodies (P < 0.001) and lower fasting C-peptide levels (P < 0.001). GAD antibodies and C-peptide correlated negatively (r = -0.40; P = 0.009). In the comparison of individuals with LADA and type 2 diabetes, all without the need for insulin, markers of metabolic syndrome were equally prevalent and pronounced. Age, C-peptide, and glucose levels were also similar. In the comparison of insulin-treated individuals with LADA and type 2 diabetes, more patients with LADA received insulin (40 vs. 22%, P < 0.001) and C-peptide levels were lower (P < 0.001). Patients with LADA were leaner but were still overweight (mean BMI 28.7 vs. 30.9 kg/m2 in type 2 diabetes, P < 0.001). In the comparison of type 2 diabetic patients with and without insulin, insulin-treated subjects were more obese and had higher A1C and lower C-peptide levels (P < 0.001).. Our conclusions are that 1) the need for insulin treatment in LADA is linked to the degree of autoimmunity and beta-cell failure, 2) subjects with LADA and type 2 diabetes without the need for insulin treatment are phenotypically similar, and 3) insulin treatment in type 2 diabetic patients is associated with both insulin resistance and beta-cell insufficiency. Topics: Adult; Aged; Autoantibodies; Autoimmunity; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Insulin; Metabolic Syndrome; Middle Aged; Norway; Perception; Phenotype; Surveys and Questionnaires; Young Adult | 2009 |
Fasting plasma C-peptide and micro- and macrovascular complications in a large clinic-based cohort of type 1 diabetic patients.
A protective effect of residual beta-cell function on microvascular complications of type 1 diabetes has been suggested. Our aim was to retrospectively evaluate the association of fasting plasma C-peptide values with micro- and macrovascular complications.. We recruited a clinic-based cohort of 471 type 1 diabetic patients born after 1945 and cared for in the period 1994-2004. Centralized measurements and standardized procedures of ascertainment of micro- and macrovascular complications were employed. Individual cumulative averages of A1C up to 2007 were calculated.. Residual beta-cell secretion was detected even many years after diabetes diagnosis. In multivariate linear regression analysis, fasting plasma C-peptide values were positively associated with age at diagnosis (beta = 0.02; P < 0.0001) and triglycerides (beta = 0.20; P = 0.05) and inversely associated with diabetes duration (beta = -0.03; P < 0.0001) and HDL cholesterol (beta = -0.006; P = 0.03). The final model explained 21% of fasting C-peptide variability. With respect to fasting C-peptide values in the lowest tertile (<0.06 nmol/l), higher values were associated with lower prevalence of microvascular complications (odds ratio [OR] 0.59 [95% CI 0.37-0.94]) independently of age, sex, diabetes duration, individual cumulative A1C average during the study period, hypertension, and cardiovascular diseases. No association was evident with macrovascular complications (0.77 [0.38-1.58]).. Our study shows an independent protective effect of residual beta-cell function on the development of microvascular complications in type 1 diabetes, suggesting the potential beneficial effect of treatment that allows the preservation of even modest beta-cell function over time. Topics: Adult; Age of Onset; Blood Pressure; Body Mass Index; C-Peptide; Cardiovascular Diseases; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Fasting; Female; Humans; Hypertension; Insulin-Secreting Cells; Italy; Male; Multivariate Analysis; Odds Ratio; Regression Analysis | 2009 |
The polymorphism Arg585Gln in the gene of the sterol regulatory element binding protein-1 (SREBP-1) is not a determinant of ketosis prone type 2 diabetes (KPD) in Africans.
Ketosis prone type 2 diabetes (KPD) is an atypical form of diabetes described mainly in people of sub-Saharan African origin. Its pathogenesis is unknown, although we have previously described a high prevalence of glucose-6-phosphate-dehydrogenase (G6PD) deficiency in patients with KPD. However, 50% of these deficient patients lacked the G6PD gene mutation. The isoforms of the transcription factor sterol regulatory element binding protein 1 (SREBP-1) are known to stimulate G6PD gene expression, and some polymorphisms in the SREBP-1 gene (SREBF-1) have been described only in Africans. We investigated one of these, the Arg585Gln polymorphism, in a candidate gene approach for KPD.. We examined the presence of the Arg585Gln polymorphism in SREBF-1 in 217 consecutive unrelated Africans [73 patients with KPD, 80 with classical type 2 diabetes (T2D) and 64 nondiabetic subjects]. Patients underwent clinical and biochemical evaluations, and were assessed for G6PD activity and insulin secretion (glucagon test).. There were no differences in frequency of the Arg585Gln polymorphism and the 585Gln allele among the three groups (allele frequency: KPD: 0.089, T2D: 0.031, nondiabetic group: 0.070; P=0.1). When the 585Gln allele frequency was compared separately between patients with KPD and those with T2D, it was significantly higher in the former (P=0.032). There was no difference between carriers and noncarriers of the 585Gln allele regarding G6PD activity and insulin secretion.. The results of this exploratory study show that the polymorphism Arg585Gln in SREBF-1 is not associated with the KPD phenotype. Further studies in larger populations are needed to confirm our findings. Topics: Adult; Amino Acid Substitution; Arginine; Black People; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamine; Humans; Lipids; Male; Middle Aged; Polymorphism, Genetic; Sterol Regulatory Element Binding Protein 1 | 2009 |
Relevance of cytotoxic alloreactivity under different immunosuppressive regimens in clinical islet cell transplantation.
Islet or beta cell transplantation provides a promising cure for type 1 diabetes patients, but insulin-independency decreases frequently over time. Immunosuppressive regimens are implemented attempting to cope with both auto- and alloimmunity after transplantation. We analysed the influence of different immunotherapies on autoreactive and alloreactive T cell patterns and transplant outcome. Patients receiving three different immunosuppressive regimens were analysed. All patients received anti-thymocyte globulin induction therapy. Twenty-one patients received tacrolimus-mycophenolate mofetil maintenance immunosuppression, whereas the other patients received tacrolimus-sirolimus (SIR, n = 5) or SIR only (n = 5). Cellular autoreactivity and alloreactivity (CTL precursor frequency) were measured ex vivo. Clinical outcome in the first 6 months after transplantation was correlated with immunological parameters. C-peptide levels were significantly different between the three groups studied (P = 0.01). We confirm that C-peptide production was correlated negatively with pretransplant cellular autoreactivity and low graft size (P = 0.001, P = 0.007 respectively). Combining all three therapies, cellular autoimmunity after transplantation was not associated with delayed insulin-independence or C-peptide production. In combined tacrolimus-SIR and SIR-treated patients, CTL alloreactivity was associated with less insulin independence and C-peptide production (P = 0.03). The percentage of donors to whom high CTLp frequencies were measured was lower in insulin-independent recipients (P = 0.03). In this cohort of islet cell graft recipients, clinical outcome in the first 6 months after transplantation correlates with the applied immunosuppressive regimen. An association exists between insulin-independence and lower incidence of CTL alloreactivity towards donor human leucocyte antigen. This observational study demonstrates the usefulness of monitoring T cell reactivity against islet allografts to correlate immune function with graft survival. Topics: Adult; Autoimmunity; C-Peptide; Cells, Cultured; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Follow-Up Studies; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Lymphocyte Activation; Male; Middle Aged; Mycophenolic Acid; Postoperative Care; Sirolimus; T-Lymphocytes, Cytotoxic; Tacrolimus; Treatment Outcome | 2009 |
Clinical islet transplantation in Japan.
The results of clinical islet transplantation in Japan are, here in, reported and discussed its efficacy and problems.. Since the first islet transplantation was performed in 2004, 65 islet isolations and 34 islet transplantations to 18 type 1 diabetic patients have been performed in Japan.. Following islet transplantation, patients experienced decreased insulin requirements and lower hemoglobin A1C levels, and positive serum C-peptide levels. All patients achieved stabilized blood glucose levels and the disappearance of hypoglycemic unawareness. Although three patients achieved insulin independency for a limited period, persistent islet graft function was difficult to maintain. Overall islet graft survival was 86.5% at 6 months, 78.7% at 1 year, and 62.9% at 2 years after the first islet transplantation. In our institution, we carried out 23 islet isolations and six islet transplantations to four patients. Although insulin independency was not achieved, all patients showed a disappearance of hypoglycemic unawareness.. Using data from the Japanese Trial of Islet Transplantation, the effectiveness of islet transplantation was shown even when using the pancreata from non-heart-beating donors. Although there are a number of problems to be solved and further improvement is needed, we can state that the introduction of clinical islet transplantation offers hope for type 1 diabetic patients. Topics: Adolescent; Adult; Aged; C-Peptide; Cadaver; Child; Diabetes Mellitus, Type 1; Female; Graft Rejection; Graft Survival; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Japan; Male; Middle Aged; Organ Preservation; Outcome Assessment, Health Care; Patient Selection; Tissue Donors | 2009 |
Identifying latent autoimmune diabetes in adults in Korea: the role of C-peptide and metabolic syndrome.
We aimed to establish the prevalence and characteristics of latent autoimmune diabetes in adults (LADA) and compare it with type 2 diabetes in 1370 Korean patients. The prevalence of LADA was 5.1%. Low C-peptide level and absence of metabolic syndrome were variables independently associated with the diagnosis of LADA. Topics: Adult; Age of Onset; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin Resistance; Korea; Male; Metabolic Syndrome; Middle Aged; Prevalence | 2009 |
Good glycemic control remains crucial in prevention of late diabetic complications--the Linköping Diabetes Complications Study.
Several intervention studies have convincingly demonstrated the importance of good glycemic control to avoid long-term diabetic complications, but the importance of other risk factors remains controversial. We previously reported a markedly reduced incidence of severe retinopathy and nephropathy during the past decades in an unselected population of type 1 diabetes mellitus diagnosed in childhood. The aim of the present study was to analyze possible risk factors, which could explain the improved prognosis.. In this longitudinal population-based cohort study, we followed all 269 patients in whom type 1 diabetes mellitus was diagnosed in childhood 1961-1985 in a well-defined geographical area in Sweden. The patients were followed until the end of 1990 s. Multivariable regression models were used to analyze the importance of hemoglobin A1c (HbA(1c)), diabetes duration, blood pressure, cardiovascular risk factors and persisting C-peptide secretion for the development of diabetic retinopathy and nephropathy.. Beside longer duration and higher HbA(1c), blood pressure and lipid values were higher and cardiovascular disease and smoking were more common in patients with severe complications. However, multivariable analysis abolished these associations. Diabetes duration and long-term HbA(1c) were the only significant independent risk factors for both retinopathy and nephropathy. The risk of overt nephropathy increased substantially when HbA(1c) was above 9.6% [Diabetes Control and Complications Trial (DCCT) corrected value], while the risk of severe retinopathy increased already when HbA(1c) exceeded 8.6%.. In this unselected population, glycemic control was the only significant risk factor for the development of long-term complications. Topics: Age of Onset; Albuminuria; Blood Glucose; Blood Pressure; Body Mass Index; C-Peptide; Cardiovascular Diseases; Child; Cholesterol; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Glycated Hemoglobin; Homeostasis; Humans; Triglycerides | 2009 |
Functional beta-cell mass and insulin sensitivity is decreased in insulin-independent pancreas-kidney recipients.
To compare functional beta-cell mass and insulin sensitivity in insulin-independent pancreas-kidney recipients with that in age- and body mass index-matched nondiabetic kidney recipients and normal controls.. All transplant recipients were on maintenance immunosuppression with mycophenolate mofetil and tacrolimus since more than 2.7 years (2.2-3.8 years). Their C-peptide release was measured during a 170-min hyperglycemic clamp, first in absence and then in presence of glucagon. Data were compared with those after glucose stimulation alone. Insulin sensitivity under basal and stimulated conditions was calculated using homeostasis model assessment of insulin resistance and insulin sensitivity index, respectively.. Functional beta-cell mass in pancreas-kidney recipients with systemic venous drainage was reduced, representing, respectively, 63% and 80% of that in healthy controls and kidney recipients. Pancreas-kidney recipients exhibited lower insulin sensitivity than healthy controls (homeostasis model assessment of insulin resistance was 0.8, 0.7-1.1 vs. 0.4, 0.3-0.8; P=0.02 and insulin sensitivity index was 17, 12-24 mg/kg/min per 100 microU/mL vs. 31, 20-38 mg/kg/min per 100 microU/mL; P=0.04).. Using a hyperglycemic clamp, the functional beta-cell mass in insulin-independent pancreas-kidney recipients was found to be 37% and 20% lower than in healthy controls and nondiabetic kidney recipients. Topics: Adult; Blood Glucose; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucose Clamp Technique; Glycated Hemoglobin; Humans; Immunosuppressive Agents; Insulin; Insulin-Secreting Cells; Kidney Diseases; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Reference Values | 2009 |
Erythropoietin during hypoglycaemia in type 1 diabetes: relation to basal renin-angiotensin system activity and cognitive function.
Preservation of cognitive function during hypoglycaemic episodes is crucial for patients with insulin-treated diabetes to avoid severe hypoglycaemic events. Erythropoietin has neuroprotective potential. However, the role of erythropoietin during hypoglycaemia is unclear. The aim of the study was to explore plasma erythropoietin response to hypoglycaemia and the relationship to basal renin-angiotensin system (RAS) activity and cognitive function.. We performed a single-blinded, controlled, cross-over study with induced hypoglycaemia or maintained glycaemic level. Nine patients with type 1 diabetes with high and nine with low activity in RAS were studied. Hypoglycaemia was induced using a standardized insulin-infusion.. Overall, erythropoietin concentrations increased during hypoglycaemia. In the high RAS group erythropoietin rose 29% (p=0.032) whereas no significant response was observed in the low RAS group (7% increment; p=0.43). Independently, both hypoglycaemia and high RAS activity were associated with higher levels of erythropoietin (p=0.02 and 0.04, respectively). Low plasma erythropoietin at baseline was associated with poorer cognitive performance during hypoglycaemia.. Hypoglycaemia triggers a rise in plasma erythropoietin in patients with type 1 diabetes. The response is influenced by basal RAS activity. Erythropoietin may carry a neuroprotective potential during hypoglycaemia. Topics: Adult; Blood Glucose; C-Peptide; Cognition; Creatinine; Cross-Over Studies; Diabetes Mellitus, Type 1; Erythropoietin; Female; Glomerular Filtration Rate; Glycated Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Male; Middle Aged; Renin-Angiotensin System; Single-Blind Method | 2009 |
Pregnancy-induced rise in serum C-peptide concentrations in women with type 1 diabetes.
The purpose of this study was to investigate whether pregnancy induces increased insulin production as a marker of improved beta-cell function in women with long-term type 1 diabetes.. This was a prospective study of 90 consecutive pregnant women with type 1 diabetes. At 8, 14, 21, 27, and 33 weeks blood samples were drawn for measurements of A1C, C-peptide, and serum glucose. C-peptide (detection limit: 6 pmol/l) was considered stimulated at a corresponding serum glucose concentration >or=5.0 mmol/l. GAD antibody concentration was determined at 8 and 33 weeks in 35 women.. C-peptide concentrations gradually increased throughout pregnancy regardless of serum glucose concentrations in the 90 women with a median duration of diabetes of 17 years (range 1-36 years). Among 35 women with paired recordings of stimulated C-peptide, C-peptide production was detectable in 15 (43%) at 8 weeks and in 34 (97%) at 33 weeks (P < 0.0001), and median C-peptide gradually increased from 6 to 11 pmol/l (P = 0.0004) with a median change of 50% (range -50 to 3,271%) during pregnancy. GAD antibodies were present in 77% with no change from 8 to 33 weeks (P = 0.85). Multivariate regression analysis revealed a positive association between the absolute increase in C-peptide concentrations during pregnancy and decreased A1C from 8 to 33 weeks (P = 0.003).. A pregnancy-induced increase in C-peptide concentrations in women with long-term type 1 diabetes was demonstrated, even in women with undetectable C-peptide concentrations in early pregnancy. This increase is suggestive of improved beta-cell function and was associated with improvement in glycemic control during pregnancy. Topics: Adult; Age of Onset; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Postpartum Period; Pregnancy; Pregnancy Complications; Pregnancy Trimester, First; Pregnancy Trimester, Second; Pregnancy Trimester, Third; Prospective Studies; Weight Gain | 2009 |
Effects of streptozotocin-induced diabetes in domestic pigs with focus on the amino acid metabolism.
Streptozotocin (STZ) given intravenously destroys pancreatic beta cells and is widely used in animal models to mimic type 1 diabetes. The effects of STZ on the clinical state of health and metabolism were studied in six high health certified domestic pigs weighing 19+/-1.3 kg at the start of the experiment. A single STZ dose of 150 mg/kg of body weight successfully induced hyperglycaemia and alterations in amino acid metabolism. Within 9 h after STZ administration, the blood glucose values fell from 5.4-7.5 mmol/L to 0.8-2.2 mmol/L. Hypoglycaemia was treated with 0.5 g glucose/kg body weight. In all pigs, hyperglycaemia was produced 24 h after STZ treatment, and 3 days after STZ injection, the glucose concentration was >25 mmol/L. Mean C-peptide concentration was 0.25+/-0.16 microg/L since 2 days after STZ injection until the end of the study. The serum concentration of the branched-chain amino acids (BCAA) increased four-fold, and alanine and taurine decreased by approximately 70% and 50%, respectively, after STZ treatment. All but one pig remained brisk and the physical examination was normal except for a retarded growth rate and a reduction of the skeletal muscle. At the end of the study, the pigs were moderately emaciated. Postmortem examination confirmed muscle wasting and a reduction of abdominal and subcutaneous fat. In conclusion, STZ-induced diabetes in pigs fulfils the requirements for a good animal model for type 1 diabetes with respect to clinical signs of the disease and alterations in the carbohydrate and amino acid metabolism. Topics: Alanine; Amino Acids; Amino Acids, Branched-Chain; Animals; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Hyperglycemia; Insulin; Muscle, Skeletal; Swine; Taurine | 2009 |
The A-chain of insulin is a hot-spot for CD4+ T cell epitopes in human type 1 diabetes.
Type 1 diabetes (T1D) is caused by T cell-mediated destruction of the pancreatic insulin-producing beta cells. While the role of CD4(+) T cells in the pathogenesis of T1D is accepted widely, the epitopes recognized by pathogenic human CD4(+) T cells remain poorly defined. None the less, responses to the N-terminal region of the insulin A-chain have been described. Human CD4(+) T cells from the pancreatic lymph nodes of subjects with T1D respond to the first 15 amino acids of the insulin A-chain. We identified a human leucocyte antigen-DR4-restricted epitope comprising the first 13 amino acids of the insulin A-chain (A1-13), dependent upon generation of a vicinal disulphide bond between adjacent cysteines (A6-A7). Here we describe the analysis of a CD4(+) T cell clone, isolated from a subject with T1D, which recognizes a new HLR-DR4-restricted epitope (KRGIVEQCCTSICS) that overlaps the insulin A1-13 epitope. This is a novel epitope, because the clone responds to proinsulin but not to insulin, T cell recognition requires the last two residues of the C-peptide (Lys, Arg) and recognition does not depend upon a vicinal disulphide bond between the A6 and A7 cysteines. The finding of a further CD4(+) T cell epitope in the N-terminal A-chain region of human insulin underscores the importance of this region as a target of CD4(+) T cell responses in human T1D. Topics: Antigen Presentation; C-Peptide; CD4-Positive T-Lymphocytes; Cysteine; Diabetes Mellitus, Type 1; Epitope Mapping; Epitopes, T-Lymphocyte; HLA-DR4 Antigen; Humans; Insulin; Proinsulin; Receptors, Antigen, T-Cell | 2009 |
Early metabolic markers of islet allograft dysfunction.
Islet transplantation can restore normoglycemia to patients with unstable type 1 diabetes mellitus, but long-term insulin independence is usually not sustained. Identification of predictor(s) of islet allograft dysfunction (IGD) might allow for early intervention(s) to preserve functional islet mass.. Fourteen islet transplantation recipients with long-term history of type 1 diabetes mellitus underwent metabolic testing by mixed meal tolerance test, intravenous glucose tolerance test, and arginine stimulation test every 3 months postislet transplant completion. Metabolic responses were compared between subjects who maintained insulin independence at 18 months (group 1; n=5) and those who restarted insulin within 18 months (group 2; n=9). Data were analyzed before development of islet graft dysfunction and while insulin independent.. The 90-min glucose, time-to-peak C-peptide, and area under the curve for glucose were consistently higher in group 2 and increased as a function of time. At 12 months, acute insulin release to glucose in group 2 was markedly reduced as compared with baseline (5.62+/-1.21 microIU/mL, n=4 vs. 16.14+/-3.69 microIU/mL, n=8), whereas it remained stable in group 1 (22.36+/-4.98 microIU/mL, n=5 vs. 27.70+/-2.83 microIU/mL, n=5). Acute insulin release to glucose, acute C-peptide release to glucose (ACpRg), and mixed meal stimulation index were significantly decreased and time-to-peak C-peptide, 90-min glucose, and area under the curve for glucose were significantly increased when measured at time points preceding intervals where IGD occurred compared with intervals where there was no IGD.. The intravenous glucose tolerance test and mixed meal tolerance test may be useful in the prediction of IGD and should be essential components of the metabolic testing of islet transplant recipients. Topics: Arginine; Awareness; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Fasting; Follow-Up Studies; Glucose Tolerance Test; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Postoperative Complications; Transplantation, Homologous | 2009 |
[Pancreatic function assessment in type 1 diabetes mellitus patients according to disease duration].
Patients with type 1 diabetes (T1D) may exhibit some residual insulin secretion for many years after their diagnosis. This has been associated with a more favorable prognosis.. To analyze insulin secretion in individuals with T1D using C-peptide (CP) response to glucagon and comparing patients with recent onset (<5 years - Group 1) and long-standing disease (>5 years -Group 2).. Subjects with T1D had their blood sampled before (fasting) and 6 minutes after glucagon infusion for CP, HbA1c and anti-GAD measurement.. Forty-three individuals were evaluated, 22 in Group 1 and 21 in Group 2. Preserved insulin secretion (CP >1.5 ng/mL) was observed in 6 (13.9%) and in 8 (18.6%) patients before (CP 1) and after (CP 2) glucagon stimulus, respectively, showing no difference between the groups (p=0.18 and 0.24). CP 1 and CP 2 were detectable (>0.5 ng/dL) in 13 (30.2%) and 18 (41.9%) patients, respectively. Both were more frequent in Group 1 than in Group 2 (p=0.45 for CP1/p=0.001 for CP 2). Similar serum levels where seen between the groups, both before and after stimulus (1.4+/-0.8 vs. 1.2+/-1.0; p=0.69 and 1.8+/-1.5 vs. 1.7+/-0.8; p=0.91). Group 1 presented an inverse correlation between disease duration and CP 2 (R=-0.58; p=0.025).. A significant number of patients with T1D have detectable residual insulin secretion, especially in the first 5 years of disease. These subjects are an ideal population for clinical trials that target the prevention of beta cell function loss in T1D. Topics: Adolescent; C-Peptide; Chi-Square Distribution; Diabetes Mellitus, Type 1; Female; Glucagon; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Male; Pancreas; Time Factors; Young Adult | 2009 |
Pancreas-kidney transplantation and the evolution of pancreatic autoantibodies.
The recurrence or persistence of pancreatic autoantibodies after pancreas-kidney transplantation (PKT) is an intriguing finding. We prospectively analyzed 77 PKTs, searching for risk factors for the expression of these autoimmune markers and their impact on pancreas graft function. Among the 77 PKTs, 24.7% had 0 HLA matches, 20.8% displayed delayed graft function, and 14.3% had acute rejection episodes. Immunosuppression included antithymocyte globulin (ATG), tacrolimus, mycophenolate mofetil (MMF), and steroids. Sixty-five patients had both grafts functioning as a follow-up of more than 6 months. In 11 patients anti-glutamic acid decarboxylase (GAD) positivity persists (n = 8) or has recurred (n = 3), 4 of whom show increasing titers. Two patients maintain positive islet cell antibodies (ICA) and anti-GAD antibodies. The 9 patients positive for ICA included 2 who were negative before PKT and 7 who remain positive. The "positive" group (22 patients with positive ICA and/or anti-GAD) did not differ from the global group of 65 functioning PKT in terms of acute rejection episodes, HLA match, and steroid withdrawal. Among the positive patients, there were 2 with borderline glucose levels; however, among the entire "positive" group, the mean fasting glucose, HbA1c, and C-peptide measurements were not significantly different, when compared with the other 65 PKTs. In conclusion, pancreatic autoantibodies may be persistently positive or recur after PKT, despite appropriate immunosuppression. Its impact on long-term pancreas graft survival is unknown. We could not identify risk factors for their expression. An extended follow-up with monitoring and search for other risk factors may be necessary to increase our knowledge in this field. Topics: Adult; Autoantibodies; Blood Glucose; C-Peptide; Cadaver; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Pancreas; Pancreas Transplantation; Reference Values; Retrospective Studies; Tissue Donors; Young Adult | 2009 |
Is it time to take a different approach to screening people at high risk for type 1 diabetes?
Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; Mass Screening; Risk Factors | 2009 |
From bariatric to metabolic surgery in non-obese subjects: time for some caution.
Severe obesity is associated with type 2 diabetes mellitus, and both resolve with weight loss after bariatric operations. Intestinal hormones have been identified which are stimulated by rapid nutrient delivery to the lower small bowel after certain weight-loss operations. These incretins stimulate secretion and hypertrophy of the pancreatic beta cells. Surgical procedures are now being performed to treat diabetes in adults of lesser weight, and the importance of ruling out latent autoimmune diabetes in the adult (a variety of type 1) is suggested, before experimenting with these procedures. Topics: Adult; Bariatric Surgery; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon-Like Peptide 1; Humans; Insulin Resistance; Obesity; Weight Loss | 2009 |
Incidence and time trend of type 1 and type 2 diabetes in Austrian children 1999-2007.
To analyze the time trend of the nationwide incidence of type 2 diabetes in children and adolescents < or = 15 years of age compared with type 1 diabetes between 1999 and 2007 in Austria.. In a prospective, population-based incidence study, all newly diagnosed patients with diabetes < or = 15 years of age were registered by the Austrian Diabetes Incidence Study Group. The Diabetes type was classified on the basis of clinical and laboratory findings according to ADA criteria. Time trends were estimated by linear regression models.. During the observation period, 1881 patients with type 1 diabetes and 34 patients with type 2 diabetes could be identified. Sixty-two percent of patients with type 2 diabetes were female, 56% had a positive family history for type 2 diabetes, and 74% presented with diabetes-specific symptoms. The incidence of type 1 diabetes in Austria increased from 12.0 to 18.4/100,000 (P < .001) and the incidence of type 2 diabetes remained stable below 0.6/100 000 (P = .706).. The incidence of type 2 diabetes in Austrian children is 10-fold lower than reported in other regions and did not increase over the last 8 years. During the same time period, a significant rise in the incidence of type 1 diabetes was observed. Topics: Adolescent; Austria; Bacterial Infections; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Ethnicity; Female; Genetic Predisposition to Disease; Humans; Incidence; Male; Mycoses; Polyuria; Prospective Studies; Sex Distribution; Time Factors; Weight Loss | 2009 |
Circulating endothelial progenitor cells, endothelial function, carotid intima-media thickness and circulating markers of endothelial dysfunction in people with type 1 diabetes without macrovascular disease or microalbuminuria.
Type 1 diabetes is associated with premature arterial disease. Bone-marrow derived, circulating endothelial progenitor cells (EPCs) are believed to contribute to endothelial repair. The hypothesis tested was that circulating EPCs are reduced in young people with type 1 diabetes without vascular injury and that this is associated with impaired endothelial function and increased carotid intima-media thickness (CIMT).. We compared 74 people with type 1 diabetes with 80 healthy controls. CD34, CD133, vascular endothelial (VE) growth factor receptor-2 (VEGFR-2) and VE-cadherin antibodies were used to quantify EPCs and progenitor cell subtypes using flow-cytometry. Ultrasound assessment of endothelial function by brachial artery flow-mediated dilatation (FMD) and CIMT was made. Circulating endothelial markers, inflammatory markers and plasma plasminogen activator inhibitor-1 (PAI-1) levels were measured.. CD34+VE-cadherin+, CD133+VE-cadherin+ and CD133+VEGFR-2+ EPC counts were significantly lower in people with diabetes (46-69%; p = 0.004-0.043). In people with type 1 diabetes, FMD was reduced by 45% (p < 0.001) and CIMT increased by 25% (p < 0.001), these being correlated (r = -0.25, p = 0.033). There was a significant relationship between FMD and CD34+VE-cadherin+ (r = 0.39, p = 0.001), CD133+VEGFR-2+ (r = 0.25, p = 0.037) and CD34+ (r = 0.34, p = 0.003) counts. Circulating high-sensitivity C-reactive protein, PAI-1, interleukin-6 and E-selectin were significantly higher in the diabetes group (p < 0.001 to p = 0.049), the last two of these correlating with FMD (r = -0.27, p = 0.028 and r = -0.24, p = 0.048, respectively).. These findings suggest that abnormalities of endothelial function in addition to pro-inflammatory and pro-thrombotic states are already common in people with type 1 diabetes before development of clinically evident arterial damage. Low EPC counts confirm risk of macrovascular complications and may account for impaired endothelial function and predict future cardiovascular events. Topics: Adolescent; Adult; Blood Flow Velocity; Blood Glucose; Blood Pressure; C-Peptide; Carotid Arteries; Diabetes Mellitus, Type 1; Endothelial Cells; Endothelium, Vascular; Female; Humans; Male; Plasminogen Activator Inhibitor 1; Reference Values; Tunica Intima; Tunica Media; Vascular Endothelial Growth Factor Receptor-2; Vasodilation; Young Adult | 2009 |
Pancreatic perfusion of healthy individuals and type 1 diabetic patients as assessed by magnetic resonance perfusion imaging.
Loss of pancreatic beta cell mass and function leads to the development of diabetes mellitus. Currently there is no technical way to non-invasively image islet function and mass. Murine models suggest that islets are highly vascularised organs that make a significant contribution to the total pancreatic blood flow. The current study was undertaken to test with arterial spin labelling (ASL) magnetic resonance imaging if islet mass and/or stimulation of human pancreatic islets by hyperglycaemia can differentially increase whole-pancreas perfusion, thereby distinguishing non-diabetic from type 1 diabetic patients.. We assessed pancreatic blood flow using ASL at baseline, during a hyperglycaemia clamp study (glucose at 11 mmol/l) and during recovery to euglycaemia.. Seventeen healthy volunteers and seven type 1 diabetic patients were studied. In healthy volunteers we observed no change in pancreatic blood flow during the three phases of the study. A trend for an increase in blood flow was observed in the two control tissues, the liver and kidney. Similarly, there was no significant difference in blood flow during the three stages (baseline, hyperglycaemia and recovery) in diabetic patients and there was no significant difference observed between diabetic patients and normal volunteers.. Our data suggest that in humans neither increased demand nor islet mass has a substantial influence on pancreatic perfusion. It is possible, however, that the current state-of-the art imaging technology employed in this study might not be sensitive enough to distinguish between a true effect and noise.. ClinicalTrials.gov NCT00280085. Topics: Adult; Blood Flow Velocity; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hyperglycemia; Insulin-Secreting Cells; Magnetic Resonance Imaging; Male; Middle Aged; Pancreas; Reference Values; Young Adult | 2009 |
Safety and viability of microencapsulated human islets transplanted into diabetic humans.
Transplantation of insulin-producing cells placed inside microcapsules is being trialled to overcome the need for immunosuppressive therapy.. Four type 1 diabetic patients with no detectable C-peptide received an intraperitoneal infusion of islets inside microcapsules of barium alginate (mean 178,200 islet equivalents on each of eight occasions).. C-peptide was detected on day 1 post-transplantation, and blood glucose levels and insulin requirements decreased. C-peptide was undetectable by 1-4 weeks. In a multi-islet recipient, C-peptide was detected at 6 weeks after the third infusion and remains detectable at 2.5 years. Neither insulin requirements nor glycemic control was affected. Capsules recovered at 16 months were surrounded by fibrous tissue and contained necrotic islets. No major side effects or infection occurred.. While allografting of encapsulated human islets is safe, efficacy of the cells needs to improve for the therapy to make an impact on the clinical scene. Topics: Adult; Alginates; Blood Glucose; C-Peptide; Capsules; Cell Survival; Diabetes Mellitus, Type 1; Female; Glucuronic Acid; Hexuronic Acids; Humans; Islets of Langerhans Transplantation; Male; Middle Aged | 2009 |
Differences in baseline lymphocyte counts and autoreactivity are associated with differences in outcome of islet cell transplantation in type 1 diabetic patients.
The metabolic outcome of islet cell transplants in type 1 diabetic patients is variable. This retrospective analysis examines whether differences in recipient characteristics at the time of transplantation are correlated with inadequate graft function.. Thirty nonuremic C-peptide-negative type 1 diabetic patients had received an intraportal islet cell graft of comparable size under an ATG-tacrolimus-mycophenolate mofetil regimen. Baseline patient characteristics were compared with outcome parameters during the first 6 posttransplant months (i.e., plasma C-peptide, glycemic variability, and gain of insulin independence). Correlations in univariate analysis were further examined in a multivariate model.. Patients that did not become insulin independent exhibited significantly higher counts of B-cells as well as a T-cell autoreactivity against insulinoma-associated protein 2 (IA2) and/or GAD. In one of them, a liver biopsy during posttransplant year 2 showed B-cell accumulations near insulin-positive beta-cell aggregates. Higher baseline total lymphocytes and T-cell autoreactivity were also correlated with lower plasma C-peptide levels and higher glycemic variability.. Higher total and B-cell counts and presence of T-cell autoreactivity at baseline are independently associated with lower graft function in type 1 diabetic patients receiving intraportal islet cells under ATG-tacrolimus-mycophenolate mofetil therapy. Prospective studies are needed to assess whether control of these characteristics can help increase the function of islet cell grafts during the first year posttransplantation. Topics: Adult; Anticoagulants; Antilymphocyte Serum; Biopsy; C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Insulin; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Liver; Lymphocyte Count; Male; Middle Aged; Mycophenolic Acid; Reference Values; Reoperation; T-Lymphocytes; Tacrolimus; Treatment Outcome | 2009 |
The glutamic acid decarboxylase 65 immunoglobulin G subclass profile differs between adult-onset type 1 diabetes and latent autoimmune diabetes in adults (LADA) up to 3 years after clinical onset.
Autoantibodies against glutamic acid decarboxylase 65 (GADA) are found frequently in patients with autoimmune diabetes. Immunoglobulin (Ig)G(1) is the most frequent subclass among the GADA IgG subclasses. IgG(4) is a more common subclass in latent autoimmune diabetes in adults (LADA) at clinical onset compared to type 1 diabetes. The aim of this work was to study the different GADA-IgG subclass profiles during a 3-year follow-up in these groups of autoimmune diabetes. Adult-onset subjects, classified as either type 1 (n = 40) or LADA (n = 43), were included in the study. New samples were collected every year from these patients. In addition to conventional GADA analyses, GADA-IgG subclasses were also analysed with a radioimmunoprecipitation assay using biotin-conjugated antibodies (directed against human IgG subclasses and IgM) and streptavidin Sepharose. During 3 years' follow-up, all the IgG subclass levels decreased in type 1 diabetes - IgG(1): P < 0.001; IgG(2): P < 0.001; IgG(3): P < 0.001; IgG(4): P < 0.05 (Friedman's' test) - while levels remained stable for all four subclasses in LADA. GADA IgM, however, decreased in both groups (P < 0.001). Patients with LADA have higher GADA IgG(3) and IgG(4) at clinical onset and seem to maintain the levels and profile of their IgG subclasses up to 3 years after clinical onset, while all the GADA IgG subclass levels decrease in type 1 diabetic patients. This indicates a persistent different immune response in LADA compared to type 1 diabetes and further indicates the difference in pathogenesis. Topics: Adolescent; Adult; Age of Onset; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Immunoglobulin G; Immunoglobulin M; Male; Middle Aged; Radioimmunoprecipitation Assay; Statistics, Nonparametric; Young Adult | 2009 |
Long-term metabolic control of autoimmune diabetes in spontaneously diabetic nonobese diabetic mice by nonvascularized microencapsulated adult porcine islets.
The long-term metabolic function of microencapsulated xenogeneic adult porcine islets (API) was assessed in a murine model of type 1 diabetes mellitus.. API were encapsulated in barium-gelled alginate and transplanted intraperitoneally in diabetic nonobese diabetic (NOD) mice given no immunosuppression or given costimulatory blockade (CoB; CTLA4-Ig+anti-CD154 mAb). Control mice received nonencapsulated API under the kidney capsule. Graft function was monitored by measurement of random blood glucose levels, serum glycosylated hemoglobin (HbA1c), serum porcine C peptide, in vivo glucose tolerance tests, and histologic analyses of host pancreas and graft biopsies. Host immune responses to the islet xenografts were characterized by phenotyping peritoneal cellular infiltrates and by measuring serum antiporcine antibody levels.. Without immunosuppression, nonencapsulated API functioned for less than 1 week, and microencapsulated API functioned for 35+/-14 days before rejection, associated with both a cellular and a humoral immune response. With continuous CoB, nonencapsulated API functioned for 27+/-4 days, whereas microencapsulated API functioned for >450 days with measurable levels of serum porcine C peptide, near normal in vivo glucose tolerance tests and HbA1c levels, and intact microcapsules containing viable, insulin-positive porcine islets.. Microencapsulated API restored normoglycemia for more than 1 year in spontaneously diabetic NODs given dual CoB. To our knowledge, this is the first study to document long-term normalized HbA1c, porcine C peptide, and near normal glucose tolerance in immunosuppressed diabetic NOD mice transplanted intraperitoneally with microencapsulated API. Our study suggests that transplantation of microencapsulated porcine islet xenografts may be a future treatment for patients with type 1 diabetes mellitus. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Glycated Hemoglobin; Graft Rejection; Graft Survival; Islets of Langerhans Transplantation; Mice; Mice, Inbred NOD; Swine; Transplantation Tolerance; Transplantation, Heterologous | 2009 |
Adiponectin has different mechanisms in type 1 and type 2 diabetes with C-peptide link.
Adiponectin (ApN) is considered to be responsible for reduction of inflammation and is known to be included in lipid metabolism. This study was designed to assess the role of adiponectin in patients with type 1 and type 2 diabetes and to determine parameters important in the prediction of adiponectin.. Adiponectin, high sensitive C-reactive protein, fibrinogen, homocysteine, C-peptide, and lipid panel in addition to clinical and laboratory parameters important for the definition of diabetes, obesity and the metabolic syndrome were measured in 118 patients.. The best model (R2=0.989) for predicting adiponectin in type 1 diabetes included fibrinogen, white blood cell count, uric acid and triglycerides. In type 2 diabetes the best model (R2=0.751) included C-peptide, white blood cell count, systolic blood pressure, fasting blood glucose, glycated hemoglobin and high-density lipoprotein cholesterol. ANOVA showed among-group differences in adiponectin (P=0.028), body mass index (P < 0.001), fasting blood glucose (P < 0.001) and high-density lipoprotein cholesterol (P =0.012) according to the type of diabetes. Between-group differences were also observed in adiponectin (P =0.033) and high-density lipoprotein cholesterol (P =0.009) according to sex. Adiponectin correlated (P < 0.05) with body mass index, C-peptide, pulse pressure and high-density lipoprotein cholesterol.. Adiponectin levels were higher in type 1 diabetes. The association between C-peptide and adiponectin is probably one of the reasons for their different respective levels in different types of diabetes. Interrelations between adiponectin and inflammation, dyslipidemia, C-peptide levels and sex appear to be important for complex adiponectin modulation and action. Topics: Adiponectin; Adult; C-Peptide; C-Reactive Protein; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Enzyme-Linked Immunosorbent Assay; Fibrinogen; Humans; Middle Aged; Triglycerides; Uric Acid | 2009 |
Stabilizing effect of exenatide in a patient with C-peptide-negative diabetes mellitus.
Exenatide is an incretin mimetic licensed for treatment of Type 2 diabetes poorly controlled despite maximally tolerated doses of oral therapy. Similar in structure to the natural incretin hormone glucagon-like peptide 1 (GLP-1), it helps restore underlying pathophysiological abnormalities.. We report the successful use of exenatide, combined with insulin, in a 66-year-old woman initially diagnosed with Type 2 diabetes in 1989 but now exhibiting a Type 1 phenotype. Diet, lifestyle advice and oral glucose-lowering agents were commenced but persisting poor control necessitated insulin therapy in 2005. She later presented twice in diabetic ketoacidosis, suggesting conversion to a Type 1 phenotype (postprandial C-peptide < 94 pmol/l). Despite differing insulin regimens, control remained poor with frequent hyperglycaemic and hypoglycaemic excursions, severely impairing quality of life. Whilst an inpatient in 2007 [glycated haemoglobin (HbA(1c)) 10.2%, body mass index (BMI) 31.5 kg/m(2)] exenatide was commenced in an attempt to stabilize glycaemic control. Dramatic improvements were seen and continued. Eight months later, HbA(1c) had fallen by 2% with an 8-kg weight loss and 10-unit reduction in daily insulin dose. Quality of life dramatically improved. C-peptide remains undetectable.. This patient with features of both Type 1 and Type 2 diabetes benefited greatly from exenatide with insulin therapy. The improvement seen in glycaemic control could not be attributable to enhanced insulin secretion but could be as a result of a combination of the other incretin effects (postprandial glucagon suppression, delayed gastric emptying and weight loss secondary to increased satiety) all improving insulin sensitivity, reducing insulin dose and smoothing control. Topics: Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Exenatide; Female; Humans; Hypoglycemic Agents; Overweight; Peptides; Treatment Outcome; Venoms | 2009 |
Beta-cell-mediated signaling predominates over direct alpha-cell signaling in the regulation of glucagon secretion in humans.
Given evidence of both indirect and direct signaling, we tested the hypothesis that increased beta-cell-mediated signaling of alpha-cells negates direct alpha-cell signaling in the regulation of glucagon secretion in humans.. We measured plasma glucagon concentrations before and after ingestion of a formula mixed meal and, on a separate occasion, ingestion of the sulfonylurea glimepiride in 24 basal insulin-infused, demonstrably beta-cell-deficient patients with type 1 diabetes and 20 nondiabetic, demonstrably beta-cell-sufficient individuals; the latter were infused with glucose to prevent hypoglycemia after glimepiride.. After the mixed meal, plasma glucagon concentrations increased from 22 +/- 1 pmol/l (78 +/- 4 pg/ml) to 30 +/- 2 pmol/l (103 +/- 7 pg/ml) in the patients with type 1 diabetes but were unchanged from 27 +/- 1 pmol/l (93 +/- 3 pg/ml) to 26 +/- 1 pmol/l (89 +/- 3 pg/ml) in the nondiabetic individuals (P < 0.0001). After glimepiride, plasma glucagon concentrations increased from 24 +/- 1 pmol/l (83 +/- 4 pg/ml) to 26 +/- 1 pmol/l (91 +/- 4 pg/ml) in the patients with type 1 diabetes and decreased from 28 +/- 1 pmol/l (97 +/- 5 pg/ml) to 24 +/- 1 pmol/l (82 +/- 4 pg/ml) in the nondiabetic individuals (P < 0.0001). Thus, in the presence of both beta-cell and alpha-cell secretory stimuli (increased amino acid and glucose levels, a sulfonylurea) glucagon secretion was prevented when beta-cell secretion was sufficient but not when beta-cell secretion was deficient.. These data indicate that, among the array of signals, indirect reciprocal beta-cell-mediated signaling predominates over direct alpha-cell signaling in the regulation of glucagon secretion in humans. Topics: C-Peptide; Diabetes Mellitus, Type 1; Eating; Epinephrine; Fasting; Fatty Acids, Nonesterified; Female; Glucagon; Glucagon-Secreting Cells; Homeostasis; Humans; Hypoglycemic Agents; Insulin-Secreting Cells; Male; Reference Values; Signal Transduction; Sulfonylurea Compounds | 2009 |
Improved diabetic control during oral sulfonylurea treatment in two children with permanent neonatal diabetes mellitus.
Permanent neonatal diabetes mellitus (PND), defined as diabetes diagnosed in the first 6 months of age and requiring life-long insulin therapy, is a rare disorder of unknown etiology. Activating mutations of the KCNJ11 gene, which encodes the Kir6.2 subunit of the ATP-dependent potassium channel in beta-cells, have been found to cause 30-58% of cases of PND. Sulfonylurea treatment in theses patients reduces or eliminates the need for exogenous insulin. We report two Taiwanese boys who were diagnosed with PND at 1 and 4.5 months of age. They had been treated with exogenous insulin for 6 and 15 years, respectively. In September 2006, they were both found to have a KCNJ11 mutation (valine-to-methionine at codon 59; V59M). Glibenclamide successfully increased the basal C-peptide level, lowered HbA(1c), and reduced blood sugar excursions. In one patient, the insulin dose was reduced to 0.2 U/kg/day, and the other was able to discontinue insulin altogether. These two cases from Taiwan add to the experience with similar mutations reported in Caucasians. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; DNA Mutational Analysis; Drug Therapy, Combination; Fasting; Glyburide; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Point Mutation; Potassium Channels, Inwardly Rectifying; Treatment Outcome | 2009 |
SUITO index for evaluation of efficacy of single donor islet transplantation.
Evaluation of engrafted islets mass is important for clinical care of patients after islet transplantation. Recently, we developed the secretory unit of islet transplant objects (SUITO) index, which reflected engrafted islet mass. In this study, we evaluated the SUITO index for the prediction of clinical outcome after single islet transplantation. Single islet transplantations were performed into six type 1 diabetic patients. Isolated islets were quantitatively assessed at the time of transplantation. The SUITO index was calculated as follows: fasting C-peptide (ng/dl)/[fasting blood glucose (mg/dl) - 63] x 1500. Islet yield/recipient's body weight and SUITO index were evaluated, along with HbA(1C), relative insulin dose (insulin dose posttransplant/pretransplant), and M-values. HbA(1C) improved in all cases, irrespective of the SUITO index score or islet yield/body weight. The average SUITO index from postoperative days 3 to 30 (R(2) = 0.728, p < 0.04), but not islet yield/body weight (R(2) = 0.259, p = 0.303), correlated with relative insulin dose. The daily SUITO index strongly correlated with the daily relative insulin dose (R(2) = 0.558, p < 0.0001) and weakly correlated with the daily M-values (R(2) = 0.207, p < 0.02). A SUITO index score of less than 10 was associated with increasing insulin dose even after islet transplantation. The SUITO index seems to be a better predictor of success of islet transplantations than islet yield/body weight. SUITO index is recommended to assess clinical outcome of islet transplantation. Topics: Adult; Blood Glucose; Body Weight; C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Tissue Donors; Treatment Outcome | 2009 |
2007 update on allogeneic islet transplantation from the Collaborative Islet Transplant Registry (CITR).
As of October 1, 2007, 25 North American medical institutions and one European islet transplant center reported detailed information to the Registry on 315 allograft recipients, of which 285 were islet alone (IA) and 30 were islet after kidney (IAK). Of the 114 IA recipients expected at 4 years after their last infusion, 12% were insulin independent, 16% were insulin dependent with detectable C-peptide, 40% had no detectable C-peptide, and 32% had missing C-peptide data or were lost to follow-up. Of the IA recipients, 72% achieved insulin independence at least once over 3 years and multiple infusions. Factors associated with achievement of insulin independence included islet size >1.0 expressed as IEQs per islet number [hazard ratio (HR) = 1.5, p = 0.06], additional infusions given (HR = 1.5, p = 0.01), lower pretransplant HbA(1c) (HR = 1.2 each %-age unit, p = 0.02), donor given insulin (HR = 2, p = 0.003), daclizumab given at any infusion (HR = 1.9, p = 0.06), and shorter cold storage time (HR = 1.04, p = 0.03), mutually adjusted in a multivariate model. Severe hypoglycemia prevalence was reduced from 78-83% preinfusion to less than 5% throughout the first year post-last infusion, and to 18% adjusted for missing data at 3 years post-last infusion. In Year 1 post-first infusion for IA recipients, 53% experienced a Grade 3-5 or serious adverse event (AE) and 35% experienced a severe AE related to either an infusion procedure or immunosuppression. In Year 1 post-first infusion, 33% of IA subjects and 35% of IAK subjects had an AE related to the infusion procedure, while 35% of IA subjects and only 27% of IAK subjects had an AE related to the immunosuppression therapy. Five deaths were reported, of which two were classified as probably related to the infusion procedure or immunosuppression, and 10 cases of neoplasm, of which two were classified as probably related to the procedure or immunosuppression. Islet transplantation continues to show short-term benefits of insulin independence, normal or near normal HbA(1C) levels, and sustained marked decrease in hypoglycemic episodes. Topics: Adolescent; Adult; Aged; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Europe; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; North America; Organ Preservation; Registries; Time Factors; Transplantation, Homologous; Treatment Outcome; Young Adult | 2009 |
Autologous umbilical cord blood transfusion in very young children with type 1 diabetes.
Interest continues to grow regarding the therapeutic potential for umbilical cord blood therapies to modulate autoimmune disease. We conducted an open-label phase I study using autologous umbilical cord blood infusion to ameliorate type 1 diabetes.. Fifteen patients diagnosed with type 1 diabetes and for whom autologous umbilical cord blood was stored underwent a single intravenous infusion of autologous cells and completed 1 year of postinfusion follow-up. Intensive insulin regimens were used to optimize glycemic control. Metabolic and immunologic assessments were performed before infusion and at established time periods thereafter.. Median (interquartile range [IQR]) age at infusion was 5.25 (3.1-7.3) years, with a median postdiagnosis time to infusion of 17.7 (10.9-26.5) weeks. No infusion-related adverse events were observed. Metabolic indexes 1 year postinfusion were peak C-peptide median 0.50 ng/ml (IQR 0.26-1.30), P = 0.002; A1C 7.0% (IQR 6.5-7.7), P = 0.97; and insulin dose 0.67 units * kg(-1) * day(-1) (IQR 0.55-0.77), P = 0.009. One year postinfusion, no changes were observed in autoantibody titers, regulatory T-cell numbers, CD4-to-CD8 ratio, or other T-cell phenotypes.. Autologous umbilical cord blood transfusion in children with type 1 diabetes is safe but has yet to demonstrate efficacy in preserving C-peptide. Larger randomized studies as well as 2-year postinfusion follow-up of this cohort are needed to determine whether autologous cord blood-based approaches can be used to slow the decline of endogenous insulin production in children with type 1 diabetes. Topics: Blood Glucose; Blood Transfusion, Autologous; C-Peptide; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fetal Blood; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Infant; Infusions, Intravenous; Insulin; Leukocyte Count; Time Factors | 2009 |
C-peptide an adequate endpoint in type 1 diabetes.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Endpoint Determination; Humans | 2009 |
Islet alone versus islet after kidney transplantation: metabolic outcomes and islet graft survival.
Isolated islet transplantation with infusions from two to three donor pancreata and Edmonton immunosuppression consistently achieves insulin independence in patients with type 1 diabetes. The success of this protocol has been attributed to a novel combination of immunosuppressive agents and avoidance of steroids; however, the outcome of islet transplantation may differ in kidney transplant recipients who are already immunosuppressed.. We compared the metabolic outcomes and graft survival of islet transplantation in our program where nine patients underwent islet transplantation alone treated with Edmonton immunosuppression and eight patients received islet after kidney (IAK) transplants under standard kidney transplant immunosuppression often including steroids.. Transplants in the IAK and islet transplantation alone setting demonstrated similar islet potency (islet equivalents/unit insulin reduction) and recipients from both groups routinely gained insulin independence, functional islet mass, and duration of graft survival, however, seemed superior in the IAK group.. These results suggest that better islet graft function and survival may be attained using non-Edmonton rather than Edmonton immunosuppression and can include maintenance steroid therapy. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Graft Survival; Humans; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Time Factors | 2009 |
Glutamic Acid decarboxylase therapy for recent-onset type 1 diabetes: are we at the end or the beginning of finding a cure?
Topics: Adolescent; Autoantigens; C-Peptide; Child; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Humans; Randomized Controlled Trials as Topic; T-Lymphocytes | 2009 |
Clinical assessment of obesity and insulin resistance in type 1 diabetes subjects seen at a center in Kolkata.
Type 1 diabetes mellitus (T1DM) is characterized by a selective destruction of pancreatic beta cells. Recent data suggest a role of insulin resistance (IR) along with the deficient insulin reserve.. Fifty-eight consecutive patients of T1DM, with low C-peptide levels were included. Patients with an obvious secondary cause like steroid therapy, fibrocalculous pancreatic disease, chronic infections or comorbid illness were excluded. A clinical assessment for the presence of obesity was made based on anthropometric data. Clinical markers of IR and the insulin dose required to achieve a stable glycemic control calculated in terms of body weight were also studied.. There were 30 males and 28 females with a mean age of 16.5 +/- 2.3 (5-39) years. The mean body mass index (BMI) was 19.21 +/- 3.7 and the waist circumference was 67 +/- 5.2 cms. Nineteen ( 32.75%) and six (10.34%) patients were overweight (BMI > 23) and obese (BMI > 27) respectively while 16 (27.58%) had abdominal obesity. The body fat percentage was high (> 25%) in 34 (58.62%), mean 28.33 +/- 11.4%. Acanthosis nigricans was found in 14 (24.13%) cases, hypertension in two (3.4%) but none of the girls had clinical polycystic ovarian syndrome (PCOS). The insulin dose required was 1.11 +/- 0.41 u/kg (0.3-2.9) at an glycated haemoglobin A1C (A1C) of 7.56 +/- 1.04% (4.9-9.3), it was more than 0.6 u/kg/day in 38 (65.51%) patients.. The study concludes that IR is present in a large number of Indian T1DM patients along with a high body fat percentage. Topics: Adolescent; Adult; Blood Glucose; Body Composition; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; India; Insulin; Insulin Resistance; Male; Obesity; Overweight; Waist Circumference; Young Adult | 2009 |
Glycemic instability in type 1 diabetic patients: Possible role of ketosis or ketoacidosis at onset of diabetes.
In type 1 diabetic patients, some have glycemic instability while others glycemic stability. We have developed criteria for evaluating glycemic instability and investigated the factors responsible.. Glycemic instability in 52 type 1 diabetic patients was assessed by the mean amplitude of glycemic excursions (MAGE) and M-value, and clinical characteristics of good, fair and poor control groups were compared.. The median MAGE and M-value was 6.6mmol/L and 18.7, respectively. Then MAGE >or=6.6mmol/L and M-value >or=18.7 was defined as poor control. In the 32 patients without detectable C-peptide levels, 18 patients (56%) showed poor control. The frequency of ketosis or ketoacidosis at onset of diabetes was dramatically higher in the poor control group not only in the patients as a whole but also in those without detectable C-peptide levels.. A decreased level of C-peptide is a significant factor in glycemic instability. However, some patients have glycemic stability though beta-cell function is completely depleted. The presence of ketosis or ketoacidosis at onset of diabetes may be a factor in later glycemic instability, suggesting the importance of examining patients in detail at onset of diabetes for careful follow-up to prevent progression of acute and chronic complications of diabetes. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Homeostasis; Humans; Male; Middle Aged | 2008 |
Young children (<5 yr) and adolescents (>12 yr) with type 1 diabetes mellitus have low rate of partial remission: diabetic ketoacidosis is an important risk factor.
To determine whether there are different rates of partial remission in preschool, school-age children, and adolescents with type 1 diabetes mellitus (T1DM) and to identify clinical characteristics that are associated with increased rate of partial remission.. A total of 152 consecutive patients with newly diagnosed T1DM in 2004 were studied. Clinical characteristics at diagnosis, hemoglobin A1C (HbA1C), and total daily insulin dose (TDD) at 3-month interval follow-up for 1 yr were analyzed in each age-group (group 1, aged <5 yr; group 2, aged 5-12 yr; and group 3, aged >12 yr). Partial remission was defined as TDD <0.5 units/kg/d with HbA1C <8% assessed at 6 months after diagnosis.. Young children (group 1, 26.8%) and adolescents (group 3, 29%) had low rates of partial remission compared with school-age children (group 2, 56%, p = 0.002). There were no differences in the rates of diabetic ketoacidosis (DKA), autoantibody frequency, and HbA1C at diagnosis between age-groups. DKA at diagnosis was associated with less likelihood of having partial remission (p < 0.001). There were no associations between gender, autoantibodies, and HbA1C at diagnosis and the rate of partial remission.. Young children and adolescent children with T1DM had a low rate of partial remission. Metabolic control was poorest in young children, whereas higher dose insulin in adolescents because of insulin resistance contributes to less likelihood of having partial remission. DKA at diagnosis was associated with low rate of partial remission. It is possible that the low frequency of honeymoon phase in young children reflects more aggressive beta-cell destruction in young children. Topics: Adolescent; Bicarbonates; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Glycated Hemoglobin; Humans; Infant; Ohio; Remission Induction; Remission, Spontaneous; Risk Factors | 2008 |
Basal insulin and total daily insulin dose in children with type 1 diabetes using insulin pumps.
To assess the contribution of basal insulin to the total daily dose (CBITDD) and to identify the determinant factors in children with type 1 diabetes mellitus.. Cross-sectional study in which the basal insulin requirement was established based on a memory read-out of insulin delivery from pumps. Factors such as glycated haemoglobin A1c (HbA1c), fasting C-peptide, standard deviation score of body mass index (sdsBMI) and demographic data were determined during routine hospital visits. Study group included a total of 90 well-controlled diabetic children with the mean HbA1c 6.6 +/- 0.7 (5.2-7.9), age 10.4 +/- 4.4 yr (1.1-17.9 yr), diabetes duration 3.0 +/- 2.6 yr (0.3-10.9 yr) and sdsBMI 0.08 (-2.27 to 1.79), excluding patients with ketoacidosis or infectious diseases.. Correlations between CBITDD and age (r = 0.39 and p < 0.005) and diabetes duration (r = 0.61 and p < 0.0001) and an inverse correlation with C-peptide (r = -0.41 and p = 0.0001) were found. C-peptide-positive patients had a significantly lower percentage of basal insulin compared with C-peptide-negative patients (20.6 +/- 11 vs. 31.6 +/- 11.0%, respectively; p = 0.0004); yet, no significant difference in total insulin daily dose (0.65 +/- 0.3 vs. 0.78 +/- 0.2 U/kg/d, respectively) was observed.. The percentage of basal insulin in diabetic children is below 50% and in well-controlled diabetic children is related to the fasting C-peptide level, age of patient and diabetes duration but not to HbA1c and sdsBMI. Topics: Adolescent; Body Mass Index; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems | 2008 |
Too much glucagon, too little insulin: time course of pancreatic islet dysfunction in new-onset type 1 diabetes.
To determine the time course of changes in glucagon and insulin secretion in children with recently diagnosed type 1 diabetes.. Glucagon and C-peptide concentrations were determined in response to standard mixed meals in 23 patients with type 1 diabetes aged 9.4 +/- 4.6 years, beginning within 6 weeks of diagnosis, and every 3 months thereafter for 1 year.. Glucagon secretion in response to a physiologic stimulus (mixed meal) increased by 37% over 12 months, while C-peptide secretion declined by 45%. Fasting glucagon concentrations remained within the normal (nondiabetic) reference range.. Postprandial hyperglucagonemia worsens significantly during the first year after diagnosis of type 1 diabetes and may represent a distinct therapeutic target. Fasting glucagon values may underestimate the severity of hyperglucagonemia. The opposing directions of abnormal glucagon and C-peptide secretion over time support the link between dysregulated glucagon secretion and declining beta-cell function. Topics: Adolescent; Age of Onset; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Follow-Up Studies; Glucagon; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 2008 |
Clinical manifestations and beta cell function in Swedish diabetic children have remained unchanged during the last 25 years.
The incidence of type 1 diabetes in childhood has doubled in Sweden during the last decades. Environmental factors may cause a different disease process, residual beta cell function and clinical manifestation. Insulin therapy has become more intensive. The aim of this study was to examine the clinical characteristics at onset, C-peptide secretion during the first years after diagnosis and if there was any secular trends during the last 25 years.. All 316 children diagnosed with type 1 diabetes during 1976--2000 and living in the Linköping area were included. Information about clinical characteristics at diagnosis, duration of partial remission, insulin therapy at diagnosis and during the first years was collected from medical records. C-peptide secretion (fasting and stimulated) was measured regularly during the first 5 years. For analysis, the population was divided in five cohorts according to the year of diagnosis.. The clinical characteristics at onset were unchanged as well as duration of partial remission. C-peptide secretion was highest after 3 months and then declined gradually. After 5 years 32.7% of the patients had measurable fasting C-peptide, but only 6.5% > 0.1 nmol/L. HbA1c and insulin doses were lower in patients with persistent fasting C-peptide secretion > 0.1 nmol/L. The cohort 1996--2000 had higher stimulated C-peptide secretion at diagnosis and at 3 months, after longer follow-up there was no difference.. The clinical characteristics at diagnosis, partial remission and duration of C-peptide secretion have remained largely unchanged for the last 25 years. Topics: Adolescent; Age of Onset; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemic Agents; Incidence; Insulin; Insulin-Secreting Cells; Male; Sweden | 2008 |
The use of exenatide in islet transplant recipients with chronic allograft dysfunction: safety, efficacy, and metabolic effects.
A current limitation of islet transplantation is reduced long-term graft function. The glucagon-like peptide-1 receptor agonist, exenatide (Byetta, Amylin Pharmaceuticals, CA) has properties that could improve existing islet function, prevent further loss of islet mass and possibly even stimulate islet regeneration.. This prospective study evaluated the safety, efficacy, and metabolic effects of exenatide in subjects with type 1 diabetes mellitus and islet allograft dysfunction requiring exogenous insulin.. Sixteen subjects commenced exenatide, 12 continue (follow-up 214+/-57 days; range 108-287), four (25%) discontinued medication because of side effects. At 6 months, exogenous insulin was significantly reduced with stable glycemic control (0.15+/-0.02 vs. 0.11+/-0.025 U/kg per day; P<0.0001); three subjects discontinued insulin from 4, 5, and 9 U/day, respectively, two sustained insulin independence with A1c reduction below graft dysfunction criteria. Postprandial capillary blood glucose was significantly decreased (129.4+/-3.8 vs. 118.7+/-4.6 mg/dL; P<0.001), C-peptide and C-peptide-to-glucose ratio increased significantly by 5th and 6th months of treatment (ratio, 1.09+/-0.15 vs. 1.52+/-0.18; P<0.05). Weight loss more than 3 kg occurred in 8 of 12 (67%) subjects. Stimulation testing demonstrated improved glucose disposal and C-peptide secretion (glucose area under the curve 52,332+/-3,219 vs. 42,072+/-1,965; P=0.002 mg x min x dL, mixed meal stimulation index 0.50+/-0.06 vs. 0.66+/-0.09; P=0.03 pmol x mL), with marked suppression of glucagon secretion and progressive increase in amylin secretion. Side effects were more frequent and severe compared with published reports in type 2 diabetes, tolerated doses were lower.. Exenatide was tolerated in this patient population after appropriate dose titration and there appeared to be gradual but sustained positive effects on glycemic control and islet graft function. Topics: Adult; Amyloid; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exenatide; Feasibility Studies; Glucagon; Graft Rejection; Graft Survival; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Islet Amyloid Polypeptide; Islets of Langerhans Transplantation; Middle Aged; Peptides; Prospective Studies; Time Factors; Transplantation, Homologous; Treatment Outcome; Venoms | 2008 |
Pathology of an islet transplant 2 years after transplantation: evidence for a nonimmunological loss.
We report the immunological and pathological findings of a 52-year-old woman, who died two years after the second of two islet transplants performed using the Edmonton protocol. After each islet transplant, she gradually lost insulin independence while maintaining low levels of C-peptide secretion.. A complete autopsy was performed including pathological and immunohistochemical analysis of hepatic allogeneic islets and native pancreatic islets to identify rejection or autoimmunity. Elispots assays for allogeneic sensitization and autoantibody assays for autoimmunity were performed antemortem after her islet transplantations to test in vitro for evidence of allogeneic sensitization or autoimmunity.. The cause of death was a hypertensive stroke. Small numbers of islets without inflammation were identified within portal venules and stained with insulin. The atrophic pancreas contained small numbers of islets, which stained for insulin, and lacked any inflammation within or adjacent to the islets. In vitro assays for alloantibodies were negative, and Elispots assays failed to identify allogeneic sensitization. In vitro assays for diabetic associated autoantibodies did not identify autoimmune resensitization. The allografted kidney showed only early changes of recurrent diabetic nephropathy, and no evidence of rejection.. In summary, no evidence was found to support an immunological basis (either allo or autoimmunity) for the slow loss of intrahepatic islets, which may, therefore, be related to nonimmunological anatomic and physiological abnormalities of islets infused into the portal veins or to drug toxicity. Topics: Atrophy; Autopsy; C-Peptide; Diabetes Mellitus, Type 1; Fatal Outcome; Female; Glycated Hemoglobin; Graft Rejection; Graft Survival; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Middle Aged; Portal Vein; Treatment Failure | 2008 |
Mixed-meal tolerance test versus glucagon stimulation test for the assessment of beta-cell function in therapeutic trials in type 1 diabetes.
Beta-cell function in type 1 diabetes clinical trials is commonly measured by C-peptide response to a secretagogue in either a mixed-meal tolerance test (MMTT) or a glucagon stimulation test (GST). The Type 1 Diabetes TrialNet Research Group and the European C-peptide Trial (ECPT) Study Group conducted parallel randomized studies to compare the sensitivity, reproducibility, and tolerability of these procedures.. In randomized sequences, 148 TrialNet subjects completed 549 tests with up to 2 MMTT and 2 GST tests on separate days, and 118 ECPT subjects completed 348 tests (up to 3 each) with either two MMTTs or two GSTs.. Among individuals with up to 4 years' duration of type 1 diabetes, >85% had measurable stimulated C-peptide values. The MMTT stimulus produced significantly higher concentrations of C-peptide than the GST. Whereas both tests were highly reproducible, the MMTT was significantly more so (R(2) = 0.96 for peak C-peptide response). Overall, the majority of subjects preferred the MMTT, and there were few adverse events. Some older subjects preferred the shorter duration of the GST. Nausea was reported in the majority of GST studies, particularly in the young age-group.. The MMTT is preferred for the assessment of beta-cell function in therapeutic trials in type 1 diabetes. Topics: Adolescent; Adult; Age of Onset; Biomarkers; C-Peptide; Child; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diet, Diabetic; Fasting; Glucagon; Humans; Insulin-Secreting Cells; Racial Groups; Random Allocation; Sensitivity and Specificity | 2008 |
Quantitative in vivo islet potency assay in normoglycemic nude mice correlates with primary graft function after clinical transplantation.
Reliable assays are critically needed to monitor graft potency in islet transplantation (IT). We tested a quantitative in vivo islet potency assay (QIVIPA) based on human C-peptide (hCP) measurements in normoglycemic nude mice after IT under the kidney capsule. QIVIPA was initially tested by transplanting incremental doses of human islets. hCP levels in mice were correlated with the number of transplanted islet equivalents (r(2) = 0.6, P<0.01). We subsequently evaluated QIVIPA in eight islet preparations transplanted in type 1 diabetic patients. Conversely to standard criteria including islet mass, viability, purity, adenosine triphosphate content, or glucose stimulated insulin secretion, hCP in mice receiving 1% of the final islet product was correlated to primary graft function (hCP increase) after IT (r(2)=0.85, P<0.01). QIVIPA appears as a reliable test to monitor islet graft potency, applicable to validate new methods to produce primary islets or other human insulin secreting cells. Topics: Animals; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Gene Expression Regulation; Graft Survival; Humans; Insulin; Insulin Resistance; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Mice, Nude; Radioimmunoassay; Time Factors | 2008 |
Oxidizing and reducing responses in type 1 diabetic patients determined up to 5 years after the clinical onset of the disease.
Oxidative stress has been suggested to be the mediator of hyperglycaemia-induced diabetic complications. For this study we asked whether a significant imbalance between oxidizing and plasmatic reducing responses could be observed in DM1 patients receiving intensive therapy up to 5 years following the clinical onset of the disease. A total of 16 type 1 diabetic patients (DM1) without complications and 13 non-diabetic subjects were enrolled. Clinical and biochemical parameters were compared in the two populations studied. Moreover, reactive oxygen species (ROS) generation by granulocytes and the total plasma antioxidant status were simultaneously evaluated. Granulocytes-ROS derived and plasma antioxidant status were determined by chemiluminescence assay and tetrazolium dye reduction, respectively. Type 1 diabetic patients were receiving intensive therapy by multiple daily injections. In comparison with healthy individuals, DM1 patients exhibited an increase in ROS generation whilst plasma antioxidant status was unaltered and appeared to be sufficient to prevent the onset of typical oxidative stress. The clinical characteristics and the remaining biochemical parameters studied were similar for the two groups, except for a significantly decreased plasmatic level of uric acid in DM1 patients. This study suggests that the absence of complications in DM1 patients up to 5 years after onset of the disease may be associated with the oxidizing and reducing balance which need to be maintained in order to prevent or delay the onset of oxidative stress. The effective diabetic control involves evaluation of the oxidizing/antioxidant balance besides glycaemic control. Topics: Adolescent; Adult; Age of Onset; Blood Pressure; Body Mass Index; C-Peptide; Child; Diabetes Complications; Diabetes Mellitus, Type 1; Follow-Up Studies; Granulocytes; Humans; Oxidation-Reduction; Oxidative Stress; Plasma; Reactive Oxygen Species; Reference Values; Young Adult | 2008 |
Glucose and C-peptide changes in the perionset period of type 1 diabetes in the Diabetes Prevention Trial-Type 1.
We examined metabolic changes in the period immediately after the diagnosis of type 1 diabetes and in the period leading up to its diagnosis in Diabetes Prevention Trial-Type 1 (DPT-1) participants.. The study included oral insulin trial participants and parenteral insulin trial control subjects (n = 63) in whom diabetes was diagnosed by a 2-h diabetic oral glucose tolerance test (OGTT) that was confirmed by another diabetic OGTT within 3 months. Differences in glucose and C-peptide levels between the OGTTs were assessed.. Glucose levels increased at 90 (P = 0.006) and 120 min (P < 0.001) from the initial diabetic OGTT to the confirmatory diabetic OGTT (mean +/- SD interval 5.5 +/- 2.8 weeks). Peak C-peptide levels fell substantially between the OGTTs (median change -14.3%, P < 0.001). Among the 55 individuals whose last nondiabetic OGTT was approximately 6 months before the initial diabetic OGTT, peak C-peptide levels decreased between these two OGTTs (median change -14.0%, P = 0.052). Among those same individuals the median change in peak C-peptide levels from the last normal OGTT to the confirmatory OGTT (interval 7.5 +/- 1.3 months) was -23.8% (P < 0.001). Median rates of change in peak C-peptide levels were 0.00 ng x ml(-1) x month(-1) (P = 0.468, n = 36) from approximately 12 to 6 months before diagnosis, -0.10 ng x ml(-1) x month(-1) (P = 0.059, n = 55) from 6 months before diagnosis to diagnosis, and -0.43 ng x ml(-1) x month(-1) (P = 0.002, n = 63) from the initial diabetic OGTT to the confirmatory diabetic OGTT.. It seems that postchallenge C-peptide levels begin to decrease appreciably in the 6 months before diagnosis and decrease even more rapidly within 3 months after diagnosis. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; Prediabetic State | 2008 |
Effects of glucagon on islet beta cell function in patients with diabetes mellitus.
To evaluate islet beta cell response to intravenous glucagon (a non-glucose secretagogue) stimulation in diabetes mellitus.. Nineteen patients with type 1 diabetes (T1D) and 131 patients with type 2 diabetes (T2D) were recruited in this study. T2D patients were divided into two groups according to therapy: 36 cases treated with insulin and 95 cases treated with diet or oral therapy. The serum C-peptide levels were determined at fasting and six minutes after intravenous injection of 1 mg of glucagon.. Both fasting and 6-minute post-glucagon-stimulated C-peptide levels in T1D patients were significantly lower than those of T2D patients (0.76 +/- 0.36 ng/mL vs. 1.81 +/- 0.78 ng/mL, P < 0.05; 0.88 +/- 0.42 ng/mL vs. 3.68 +/- 0.98 ng/mL, P < 0.05). In T1D patients, the C-peptide level after injection of glucagon was similar to the fasting level. In T2D, patients treated with diet or oral drug had a significantly greater fasting and stimulated C-peptide level than those patients received insulin therapy (2.45 +/- 0.93 ng/mL vs. 1.61 +/- 0.68 ng/mL, P < 0.05; 5.26 +/- 1.24 ng/mL vs. 2.15 +/- 0.76 ng/mL, P < 0.05). The serum C-peptide level after glucagon stimulation was positively correlated with C-peptide levels at fasting in all three groups (r = 0.76, P < 0.05).. The 6-minute glucagon test is valuable in assessing the function of islet beta cell in patients with diabetes mellitus. It is helpful for diagnosis and treatment of diabetes mellitus. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Middle Aged | 2008 |
[Clinical similarity and diagnostic difficulties in differentiation of diabetes mellitus type 1 and type 2 in adolescence - case report].
The authors would like to present the difficulties in differentiation of diabetes mellitus type 1 and type 2 in adolescence on the basis of two 17 years-old patients. In both patients' cases the following symptoms: polydipsia, polyuria and weight loss with hyperglycemia and glycosuria have been observed for a few months. During laboratory studies some additional abnormalities were observed: elevated HbA1c, dyslipidemia and high level of liver enzymes. Normal level of insulin as well as C-peptide lack of ketonuria and negative parameters of autoimmunologic reaction the supported diagnosis of diabetes mellitus type 2. Due to insulin therapy and metformin a correct level of glycemia was achieved.. Decompensated diabetes mellitus type 2 in adolescents may be difficult to differentiate with type 1. Topics: Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Humans; Insulin; Male | 2008 |
[Use of ABC typing to redefine subtypes of acute-onset type 1 diabetes mellitus: study of 308 patients].
To investigate the feasibility of ABC typing to redefine the subtypes of acute-onset type 1 diabetes mellitus (DM).. Radioligand assay was used to detect glutamic acid decarboxylase-antibody (GAD-Ab) and tyrosine phosphatase autoantibody (IA-2A) in 308 patients with acute-onset type 1 DM. The patients were thus divided into 2 groups: pancreatic islet auto-antibody (demonstrated as A) positive group--positive in GAD-Ab or IA-2A--and pancreatic islet auto-antibody negative group. The clinical features and frequencies of HLA-DQ genotypes of these groups were compared. Within 24 hours after the correction of diabetic ketosis or diabetic ketoacidosis and after fasting for at least 8 h fasting and postprandial venous blood samples were collected to detect the fasting C peptide (FCP, demonstrated as B) reflecting the beta cell function, and postprandial C peptide (PCP). The patients were followed up for 2 years to know the insulin dosage (< 20 U/d or > or = 20 U/d). Receiver operating characteristic curve (ROC) was drawn to judge the values of fasting C peptide, body mass index (BMI, demonstrated as C) reflecting the central obesity, and HLA-DQ genotype in further typing among the A + and A - patients and the optimal cutoff points thereof.. Compared with the A - group, the metabolic disorders at the onset were more severe, the insulin dosage at the 2-year follow-up was higher, and the percentage of susceptible HLA-DQ genotype was higher in the A + group (P < 0.05 or < 0.01). The level of FCP (B) could be used to further subtyping in both A + and A - groups, with the optimal cutoff point of 150 pmol/L in the A + group and with the optimal cutoff point of 250 pmol/L in the A - group. BMI could be used for further classification in only A - group with the optimal cutoff point of 24 kg/m2. HLA-DQ genotypes were of little value in further classification both in A + and A - groups.. ABC typing may be used as a new way to redefine the subtypes in acute-onset type 1 DM for prognosis. Topics: Acute Disease; Adolescent; Adult; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Genotype; Glutamate Decarboxylase; HLA-DQ Antigens; Humans; Male; Middle Aged; Prognosis; Protein Tyrosine Phosphatases; Radioligand Assay; Young Adult | 2008 |
Human amnion epithelial cells can be induced to differentiate into functional insulin-producing cells.
Pancreatic islet transplantation has demonstrated that long-term insulin independence may be achieved in patients suffering from diabetes mellitus type 1. However, limited availability of islet tissue means that new sources of insulin-producing cells that are responsive to glucose are required. Here, we show that human amnion epithelial cells (HAEC) can be induced to differentiate into functional insulin-producing cells in vitro. After induction of differentiation, HAEC expressed multiple pancreatic beta-cell genes, including insulin, pancreas duodenum homeobox-1, paired box gene 6, NK2 transcription factor-related locus 2, Islet 1, glucokinase, and glucose transporter-2, and released C-peptide in a glucose-regulated manner in response to other extracellular stimulations. The transplantation of induced HAEC into streptozotocin-induced diabetic C57 mice reversed hyperglycemia, restored body weight, and maintained euglycemia for 30 d. These findings indicated that HAEC may be a new source for cell replacement therapy in type 1 diabetes. Topics: Amnion; Animals; C-Peptide; Cell Differentiation; Cells, Cultured; Culture Media, Serum-Free; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Epithelial Cells; Glucose; Humans; Hyperglycemia; Insulin-Secreting Cells; Male; Mice; Mice, Inbred C57BL; Radioimmunoassay; Time Factors | 2008 |
A case of fulminant type 1 diabetes mellitus with exocrine pancreatic insufficiency and enhanced glucagon response to meal ingestion.
Non-specific aggression to endocrine alpha and beta cells as well as exocrine pancreas has been suggested in fulminant type 1 diabetes (FT1DM), while its effect on glucagon secretion and exocrine function is unknown. Here, we report a FT1DM case with exocrine pancreatic insufficiency and enhanced glucagon response to meal ingestion. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exocrine Pancreatic Insufficiency; Glucagon; Humans; Insulin; Male; Middle Aged | 2008 |
Uniformity in clinical and HLA-DR status regardless of age and gender within fulminant type 1 diabetes.
To clarify the detailed clinical features and HLA subtype in the patients with fulminant type 1 diabetes, we investigated consecutive 250 case records registered to the committee of the Japan Diabetes Society between 2000/7/15 and 2006/6/30. After the classification with age at onset or gender, clinical data and HLA DR were evaluated. As a result, the prevalence of male patients, BMI, HbA(1c) and ALT levels at the onset increased significantly according to the elder quartile, but no other data showed any significant difference. Only age at onset and blood glucose level were significantly higher in male patients than in female patients without pregnancy by multivariate analysis. The distribution of HLA DR was not different in any subtype by gender or age at onset. Our present study revealed common feature in clinical and HLA-DR status regardless of age and gender within fulminant type 1 diabetes except pregnant women. Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA-DR Antigens; Humans; Infant; Japan; Male; Middle Aged; Pregnancy; Sex Factors; Young Adult | 2008 |
Incidence of type 1 and type 2 diabetes in adults and children in Kronoberg, Sweden.
All newly diagnosed diabetes in Kronoberg during 3 years was registered, with blood samples from 1630/1666 (97.8%) adults. Those positive for GADab and/or ICA and/or C-peptide<0.25nmol/L (0.7%) were classified as type 1 diabetes, the remaining as type 2. Incidence of type 1 in 0-19-year-olds was 37.8(36.1-39.6, 95%CI) and in 20-100 year-olds 27.1(25.6-27.4) per 100 000 and year, it was bimodal with equal peaks in 0-9 year-olds and in 50-80-year-olds. Adults had type 2 incidence 378 (375-380), children 3.1 (2.6-3.6). Among adults 6.9% had type 1 and 93.1% type 2. Among antibodypositive adults (n=101), GADab were present in 90%, ICA in 71%, both GADab and ICA in 61%. Ophthalmology contact as second source was confirmed for 98%. There were no gender differences in type 1 in any age group, small ones in pediatric subgroups. In type 2 men predominated in ages above 40 years. Incidences of type 1 diabetes in both children and adults were very high and as high above age 50 years as in children. Incidence of type 2 was the highest reported from Sweden, to which new diagnostic criteria, a high degree of case-finding, and many elders, may have contributed, but results may also reflect a true increase in incidence of both types of diabetes. Topics: Adolescent; Adult; Age Distribution; Aged; Aged, 80 and over; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Sweden | 2008 |
Rate of beta-cell destruction in type 1 diabetes influences the development of diabetic retinopathy: protective effect of residual beta-cell function for more than 10 years.
Although residual beta-cell function delays the onset and progression of diabetic retinopathy in patients with type 1 diabetes, the rate of beta-cell destruction is variable.. The aim of the study was to clarify the influence of the rate of beta-cell destruction on the development and progression of diabetic retinopathy in type 1 diabetes.. We performed a historical cohort study regarding residual beta-cell function and retinopathy.. The study was conducted in the outpatient clinic of a general hospital.. A total of 254 patients with type 1 diabetes participated.. Serum C-peptide and fundus findings were evaluated longitudinally.. The cumulative incidence of mild nonproliferative diabetic retinopathy was higher in the patients without detectable beta-cell function than in those with residual beta-cell function at 20, 15, and 10 yr after the onset of diabetes (P = 0.013, P = 0.006, and P = 0.048, respectively), but not at 5 yr after the onset (P = 0.84). There were higher mean glycosylated hemoglobin values during the entire follow-up period in the patients without detectable beta-cell function at 20 and 15 yr after the onset of diabetes (P = 0.030 and P = 0.042, respectively). Positivity for HLA-A24 and -DQA1 03, as well as the acute onset of diabetes, was associated with early beta-cell loss and also with early development of diabetic retinopathy. Cox proportional hazards analysis showed that undetectable beta-cell function at 20, 15, or 10 yr after the onset of diabetes was an independent risk factor for the development of diabetic retinopathy.. Undetectable beta-cell function within 10 yr of the onset of type 1 diabetes is associated with the earlier occurrence of diabetic retinopathy. Topics: Adult; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Disease Progression; Female; Fundus Oculi; Glycated Hemoglobin; HLA Antigens; Humans; Insulin-Secreting Cells; Longitudinal Studies; Male; Multivariate Analysis; Pancreatic Function Tests | 2008 |
Immunotherapy on trial for new-onset type 1 diabetes.
Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Humans; Immunotherapy; Insulin; Insulin Secretion | 2008 |
Simultaneous measurement of plasma concentrations of proinsulin and C-peptide and their ratio with a trefoil-type time-resolved fluorescence immunoassay.
When the concentrations of 2 or more substances are measured separately, their molar ratios are subject to the additive imprecisions of the different assays. We hypothesized that the cumulative error for concentration ratios of peptides containing a common sequence might be minimized by measuring the peptides simultaneously with a "trefoil-type" immunoassay.. As a model of this approach, we developed a dual-label time-resolved fluorescence immunoassay (TRFIA) to simultaneously measure proinsulin, C-peptide, and the proinsulin-C-peptide ratio (PI/C). A monoclonal antibody captures all C-peptide-containing molecules, and 2 differently labeled antibodies distinguish between proinsulin-like molecules and true C-peptide.. The trefoil-type TRFIA was capable of measuring plasma C-peptide and proinsulin simultaneously without mutual interference at limits of quantification of 48 and 8125 pmol/L, and 2.1 and 197 pmol/L, respectively. Within-laboratory imprecision values for the trefoil-type TRFIA ranged between 8.4% and 12% for the hormone concentrations. Unlike the hormone results obtained with separate assays, imprecision did not increase when PI/C was calculated from trefoil assay results (P < 0.05). Peptide concentrations were highly correlated with results obtained in individual comparison assays (r(2) > or = 0.965; P < 0.0001). The total error for PI/C obtained with the trefoil-type TRFIA remained < or = 25% over a broader C-peptide range than with separate hormone assays (79-7200 pmol/L vs 590-4300 pmol/L C-peptide). Preliminary data indicate little or no interference by heterophile antibodies.. The developed trefoil-type TRFIA is a reliable method for simultaneous measurement of proinsulin, C-peptide, and PI/C and provides proof of principle for the development of other trefoil-type multiple-label immunoassays. Topics: Antibodies, Monoclonal; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Fluorescent Antibody Technique; Humans; Proinsulin | 2008 |
Autologous stem cell transplantation for early type 1 diabetes mellitus.
Type 1 diabetes mellitus (T1DM) is the result of the autoimmune response against pancreatic insulin producing beta cells. This autoimmune response begins months or even years before the first presentation of signs and symptoms of hyperglycemia and at the time of clinical diagnosis near 30% of beta-cell mass still remains. In daily clinical practice, the main therapeutic option for T1DM is multiple subcutaneous insulin injections that are shown to promote tight glucose control and reduce much of diabetic chronic complications, especially microvascular complications. Another important aspect related to long-term complications of diabetes is that patients with initially larger beta-cell mass suffer less microvascular complications and less hypoglycemic events than those patients with small beta-cell mass. In face of this, beta-cell preservation is another important target in the management of type 1 diabetes and its related complications. For many years, various immunomodulatory regimens were tested aiming at blocking autoimmunity against beta-cell mass and at promoting beta-cell preservation, mainly in secondary prevention trials. In this review, we summarize some of the most important studies involving beta-cell preservation by immunomodulation and discuss our preliminary data on autologous nonmyeloablative hematopoietic stem cell transplantation in newly-diagnosed T1DM. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Hematopoietic Stem Cell Transplantation; Humans; Insulin-Secreting Cells; Young Adult | 2008 |
Islet transplantation with alemtuzumab induction and calcineurin-free maintenance immunosuppression results in improved short- and long-term outcomes.
Only a minority of islet transplant recipients maintain insulin independence at 5 years under the Edmonton protocol of immunosuppression. New immunosuppressive strategies are required to improve long-term outcomes.. Three subjects with unstable type 1 diabetes mellitus underwent islet transplantation with alemtuzumab induction and sirolimus-tacrolimus maintenance for 3 months and then sirolimus-mycophenolic acid maintenance thereafter. Follow-up was more than 2 years. Comparison was with 16 historical subjects transplanted under the Miami version of the Edmonton protocol.. Insulin independence was achieved in 2 of 3 alemtuzumab and 14 of 16 historical subjects. Those who did not achieve insulin independence only received a single islet infusion. Insulin-independence rates remained unchanged in the alemtuzumab group, but decreased from 14 of 16 (88%) to 6 of 16 (38%) in the historical group over 2 years. Insulin requirements increased in the historical group while remaining stable in the alemtuzumab group. Comparison of functional measures at 3 months suggested better engraftment with alemtuzumab (P=NS). Further comparison of alemtuzumab versus historical groups, up to 24 months, demonstrated significantly better: Mixed meal stimulation index (24 months, 1.0+/-0.08 [n=3] vs. 0.5+/-0.06 pmol/mL [n=6], P<0.01), mixed meal peak C-peptide (24 months, 5.0+/-0.5 [n=3] vs. 3.1+/-0.3 nmol/mL [n=6], P<0.05), HbA1c (24 months, 5.4+/-0.15 [n=3] vs. 6.3+/-0.12 pmol/mL [n=10], P<0.01). Administration of alemtuzumab was well tolerated. There was no increased incidence of infections in alemtuzumab subjects despite profound, prolonged lymphocyte depletion.. Islet transplantation with alemtuzumab induction was well tolerated and resulted in improved short- and long-term outcomes. Further investigation is underway for validation. Topics: Adult; Alemtuzumab; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antibodies, Neoplasm; Antineoplastic Agents; Blood Glucose; Body Mass Index; C-Peptide; Calcineurin; Diabetes Mellitus, Type 1; Drug Administration Schedule; Drug Therapy, Combination; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Islets of Langerhans Transplantation; Sirolimus; Tacrolimus; Treatment Outcome | 2008 |
Protective effect of taurine on rats with experimental insulin-dependent diabetes mellitus.
Taurine had the hypoglycemic effect during experimental insulin-dependent diabetes mellitus and decreased the concentrations of glucose and fructosamine, and increased the contents of insulin, C-peptide, and glycogen in the liver. Studying the dynamics of structural changes in pancreatic tissue confirmed a positive effect of taurine on beta-cell function. The protective effect of taurine manifested in the absence of morphological signs for alloxan-induced diabetes: decrease in the number and size of pancreatic islets, change in their distribution, reduction of beta-cell count, and accumulation of homogeneous deposits in islets. Topics: Animals; Body Weight; C-Peptide; Cell Count; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diuresis; Drinking; Fructosamine; Glucose; Glycogen; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Liver; Male; Pancreas; Rats; Taurine | 2008 |
Fatty acids and insulin modulate myocardial substrate metabolism in humans with type 1 diabetes.
Normal human myocardium switches substrate metabolism preference, adapting to the prevailing plasma substrate levels and hormonal milieu, but in type 1 diabetes, the myocardium relies heavily on fatty acid metabolism for energy. Whether conditions that affect myocardial glucose use and fatty acid utilization, oxidation, and storage in nondiabetic subjects alter them in type 1 diabetes is not well known.. To test the hypotheses that in humans with type 1 diabetes, myocardial glucose and fatty acid metabolism can be manipulated by altering plasma free fatty acid (FFA) and insulin levels, we quantified myocardial oxygen consumption (MVo(2)), glucose, and fatty acid metabolism in nondiabetic subjects and three groups of type 1 diabetic subjects (those studied during euglycemia, hyperlipidemia, and a hyperinsulinemic-euglycemic clamp) using positron emission tomography.. Type 1 diabetic subjects had higher MVo(2) and lower myocardial glucose utilization rate/insulin than control subjects. In type 1 diabetes, glucose utilization increased with increasing plasma insulin and decreasing FFA levels. Myocardial fatty acid utilization, oxidation, and esterification rates increased with increasing plasma FFA. Increasing plasma insulin levels decreased myocardial fatty acid esterification rates but increased the percentage of fatty acids going into esterification.. Type 1 diabetes myocardium has increased MVo(2) and is insulin resistant during euglycemia. However, its myocardial glucose and fatty acid metabolism still responds to changes in plasma insulin and plasma FFA levels. Moreover, insulin and plasma FFA levels can regulate the intramyocardial fate of fatty acids in humans with type 1 diabetes. Topics: Adult; Blood Flow Velocity; C-Peptide; Carbon Radioisotopes; Diabetes Mellitus, Type 1; Echocardiography; Fatty Acids, Nonesterified; Female; Glucose; Glucose Clamp Technique; Heart; Humans; Insulin; Male; Myocardium; Oxygen Consumption; Patient Selection; Positron-Emission Tomography; Reference Values | 2008 |
Altered degradation of circulating nucleic acids and oligonucleotides in diabetic patients.
Foreign, infection-associated or endogenously generated circulating nucleotide motifs may represent the critical determinants for the activation of the Toll-like receptors (TLRs), leading to immune stimulation and cytokine secretion. The importance of circulating nucleases is to destroy nucleic acids and oligonucleotides in the blood stream and during cell entry. Patients with juvenile insulin-dependent diabetes, adult patients with insulin-dependent diabetes and adult patients with type 2 diabetes were allocated to the study, together with the age-matched control subjects. Plasma RNase and nuclease activity were examined, in relation to different substrates-TLRs response modifiers, and circulating RNA and oligonucleotides were isolated. The fall in enzyme activity in plasma was obtained for rRNA, poly(C), poly(U), poly(I:C), poly(A:U) and CpG, especially in juvenile diabetics. In order to test the non-enzymatic glycation, commercial RNase (E.C.3.1.27.5) and control plasma samples were incubated with increasing glucose concentrations (5, 10, 20 and 50 mmol/l). The fall of enzyme activity was expressed more significantly in control plasma samples than for the commercial enzyme. Total amount of purified plasma RNA and oligonucleotides was significantly higher in diabetic patients, especially in juvenile diabetics. The increase in the concentration of nucleotides corresponded to the peak absorbance at 270 nm, similar to polyC. The electrophoretic bands shared similar characteristics between controls and each type of diabetic patients, except that the bands were more expressed in diabetic patients. Decreased RNase activity and related increase of circulating oligonucleotides may favor the increase of nucleic acid "danger motifs", leading to TLRs activation. Topics: Adolescent; Adult; Age of Onset; Aged; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dinucleoside Phosphates; DNA; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Oligonucleotides; Polyribonucleotides; Reference Values; RNA | 2008 |
Transplant estimated function: a simple index to evaluate beta-cell secretion after islet transplantation.
The beta-score is a highly regarded approach to the assessment of transplant functionality. Our aim was to develop an index of beta-cell function that hinges on the pillars of the beta-score (daily insulin requirement and A1C), has a straightforward physiological interpretation, and does not require the execution of an insulin stimulation test.. The new index is denoted transplant estimated function (TEF) and is obtained from the daily insulin requirement and A1C. TEF estimates the amount of insulin secreted daily and can be normalized to the number of transplanted islets, thus permitting evaluation of the cost-effectiveness of the transplant. TEF was compared with the area under the curve of C-peptide [AUC(C-pep)] concentration over 24 h, as well as the acute insulin response to intravenous glucose (AIR(glu)) and to arginine (AIR(arg)). The association between TEF and beta-score was also investigated.. The correlation of TEF with 24-h AUC(C-pep) was r = 0.73 (P < 0.005), whereas that for beta-score versus 24-h AUC(C-pep) was r = 0.33 (NS). The correlation of TEF with AIR(glu) was r = 0.59 (P < 0.001) and close to that for beta-score versus AIR(glu) (r = 0.65, P < 0.001). The correlation of TEF with AIR(arg) was r = 0.33 (P < 0.005) and was similar to that for beta-score versus AIR(arg) (r = 0.34, P < 0.005). TEF and beta-score were correlated well (r = 0.69, P < 0.0001) and showed similar time profiles.. TEF estimates daily insulin secretion, it is simpler than the beta-score, and its performance against reference indexes of beta-cell secretion is in line with that exhibited by beta-score. TEF can be normalized to the number of transplanted islets and thereby provides a benchmarking tool to evaluate the cost-effectiveness of the transplant. Topics: Area Under Curve; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Models, Biological; Reproducibility of Results | 2008 |
High incidence of type 1 diabetes mellitus during or shortly after treatment with pegylated interferon alpha for chronic hepatitis C virus infection.
Development of diabetes mellitus (DM) during or shortly after treatment with interferon alpha (IFN-alpha) in patients with chronic hepatitis C virus (HCV) infection has been reported sporadically. We prospectively screened for DM during and after IFN-alpha therapy for chronic HCV infection.. Blood glucose levels of patients with chronic HCV infection were routinely assessed at all outpatient visits during and after treatment with pegylated-IFN-alpha (Peg-IFN-alpha) and ribavirin (Riba).. Between December 2002 and October 2005, 189 non-diabetic patients were treated with Peg-IFN-alpha/Riba, of whom five developed type 1 DM (2.6%), three type 2 DM (1.6%) and one an indeterminate type of DM. Classical symptoms of DM were present in three patients who developed DM shortly after cessation of Peg-IFN-alpha/Riba. In the other patients, symptoms of DM were either indistinguishable from side effects caused by Peg-IFN-alpha/Riba or absent.. Our study showed a high incidence of type 1 DM during Peg-IFN-alpha/Riba therapy for chronic HCV infection. Symptoms of DM may be absent or mistaken for Peg-IFN-alpha/Riba-associated side effects. To diagnose DM without delay, we propose routine assessment of blood glucose at all outpatient visits during and after Peg-IFN-alpha/Riba treatment in chronic HCV patients. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; DNA Probes, HLA; Female; Hepatitis C, Chronic; Humans; Interferon alpha-2; Interferon-alpha; Male; Polyethylene Glycols; Recombinant Proteins; Ribavirin | 2008 |
A case of fulminant type 1 diabetes mellitus after influenza B infection.
A 64-years-old man referred to a hospital because of high-grade fever. He was diagnosed as having influenza B by "POCTEM Influenza A/B", a rapid influenza diagnostic kit which detect some antigens of influenza virus. Six days after medication of oseltamivir phosphate, his flu-symptoms disappeared, but he complained sever thirsty. And after 2days, he suffered from loss of consciousness and was admitted to the hospital. Laboratory data on admission showed diabetes ketoacidosis, slight elevation of HbA1c level despite sever hyperglycemia, and increase of serum amylase concentration. Anti GAD antibody and anti IA-2 antibody were not detected. Urinary C-peptide excretion was undetectable and serum C-peptide levels were also undetectable after glucagon and arginin load, suggesting disappearance of endogeneous insulin secretion. Class II HLA was susceptible to fulminant type1 diabetes. Based on these findings, we diagnosed him with fulminant type1 diabetes. In Japan, only three viruses in three cases have been reported to be the trigger in the development of fulminant type 1 diabetes. They were human herpes virus 6, herpes simplex virus and Coxsackie B3 virus. This is the fourth report of fulminant type 1 diabetes developed after the established diagnosis of viral infection and the first after influenza B virus infection. The fact that fulminant type 1 diabetes developed after the infection of such a common virus suggest that factors within host will play more important roles than virus itself in the etiology of fulminant type 1 diabetes. Topics: Amylases; Antiviral Agents; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Glycated Hemoglobin; Humans; Hyperglycemia; Influenza B virus; Influenza, Human; Male; Middle Aged; Oseltamivir | 2008 |
Basal insulin switch from NPH to glargine in children and adolescents with type 1 diabetes.
Insulin glargine is a long-acting insulin analogue increasingly used instead of neutral protamine Hagedorn (NPH) insulin in young subjects with type 1 diabetes.. We evaluated the clinical course of diabetes in children and adolescents who were switched from NPH to insulin glargine.. Between August 2003 and November 2004, a total of 76 subjects were switched to glargine in our clinic, treating 340 children with type 1 diabetes. All the subjects had been receiving insulin NPH, and their serum C-peptide levels had been non-detectable for at least 1 yr. Data were collected retrospectively, and 12-18 months after the change, experiences with glargine were inquired using a questionnaire. Seven subjects (9.2%) discontinued glargine before 12 months, and seven refused to participate.. Data for 62 subjects were analyzed. At the switch (0 months), their mean age was 12.7 yr (range 5.1-17.5), mean duration of diabetes was 6.7 yr (range 1.8-14.3), and mean hemoglobin A1c was (HbA1c) 9.2%. Twelve months later (+12 months), the mean HbA1c remained similar (9.2%), the proportion of long-acting insulin was smaller (47.7 vs. 58.1%; p < 0.001), and the daily insulin dose was lower (0.97 vs. 1.05 IU/kg; p < 0.001). The number of injections was lower at +12 months (17.7% with more than five injections vs. 64.5%; p < 0.001). No differences were seen in weight for height or the number of severe hypoglycemias. Most subjects who continued with glargine for > or =12 months considered glargine better than NPH.. A switch to insulin glargine retains a similar glycemic control and does not change the number of severe hypoglycemias. Topics: Adolescent; Age of Onset; Biomarkers; Blood Glucose; Body Height; Body Weight; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Insulin Glargine; Insulin, Isophane; Insulin, Long-Acting; Male; Reference Values; Retrospective Studies | 2008 |
The PTPN22 1858T gene variant in type 1 diabetes is associated with reduced residual beta-cell function and worse metabolic control.
Evidence has been reported for a new susceptible locus for type 1 diabetes, the protein tyrosine phosphatase nonreceptor type 2 (PTPN22), which encodes a lymphoid-specific phosphatase. The aim of the study was to evaluate the influence of the C1858T variant of the PTPN22 gene on beta-cell function as measured by C-peptide levels from time of disease diagnosis through 12 months follow-up in a prospective series of 120 consecutive type 1 diabetic subjects.. The C1858T polymorphism was genotyped using TaqMan. Fasting C-peptide, A1C, and insulin requirements were determined at diagnosis and every 3 months for 12 months; their change during follow-up was analyzed using the general linear model repeated-measures procedure.. Fasting C-peptide levels were significantly lower and A1C levels were significantly higher in subjects carrying the PTPN22 1858T variant than in subjects homozygous for C1858 from time of disease diagnosis through 12 months of intensive insulin therapy follow-up (P = 0.008 and P = 0.01, respectively). These findings were independent of age at onset, sex, and HLA risk groups. The trend in C-peptide and A1C levels in the 12-month period did not differ significantly between subjects with or without the 1858T variant. Insulin dose was similar in the 1858T carriers and noncarriers.. Type 1 diabetic subjects carrying the 1858T variant show significantly lower beta-cell function and worse metabolic control at diagnosis and throughout the study period than subjects homozygous for C1858; these differences remain unchanged over the course of the first year after diagnosis. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; DNA Primers; Genetic Predisposition to Disease; Genetic Variation; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Protein Tyrosine Phosphatase, Non-Receptor Type 22 | 2008 |
Human proinsulin C-peptide reduces high glucose-induced proliferation and NF-kappaB activation in vascular smooth muscle cells.
Excessive proliferation of vascular smooth muscle cells (VSMCs) is one of the primary lesions in atherosclerosis development during diabetes. High glucose triggers VSMC proliferation and initiates activation of the transcription factor nuclear factor (NF)-kappaB. Recently, clinical studies have demonstrated that replacement therapy with C-peptide, a cleavage product of insulin, to type 1 diabetic (T1D) patients is beneficial on a variety of diabetes-associated vascular complications. However, the mechanisms underlying the beneficial activity of C-peptide on the vasculature in conditions of hyperglycemia are largely unknown. The effects of C-peptide on the proliferation of human umbilical artery smooth muscle cell (UASMC) and aortic smooth muscle cell (AoSMC) lines cultured under high glucose for 48 h were tested. To gain insights on potential intracellular signaling pathways affected by C-peptide, we analyzed NF-kappaB activation in VSMCs since this pathway represents a key mechanism for the accelerated vascular disease observed in diabetes. High glucose conditions (25 mmol/L) stimulated NF-kappaB-dependent VSMC proliferation since the addition of two NF-kappaB-specific inhibitors, BAY11-7082 and PDTC, prevented proliferation. C-peptide at the physiological concentrations of 0.5 and 1 nmol/L decreased high glucose-induced proliferation of VSMCs that was accompanied by decreased phosphorylation of IkappaB and reduced NF-kappaB nuclear translocation. These results suggest that in conditions of hyperglycemia C-peptide reduces proliferation of VSMCs and NF-kappaB nuclear translocation. In patients with T1D, physiological C-peptide levels may exert beneficial effects on the vasculature that, under high glucose conditions, is subject to progressive dysfunction. Topics: Aorta; C-Peptide; Cell Proliferation; Cells, Cultured; Diabetes Mellitus, Type 1; Endothelium, Vascular; Glucose; Humans; Ki-67 Antigen; Muscle, Smooth, Vascular; NF-kappa B; Signal Transduction; Time Factors; Transcription Factor RelA | 2008 |
Association of IL-1ra and adiponectin with C-peptide and remission in patients with type 1 diabetes.
We investigated the association of anti-inflammatory cytokine interleukin (IL)-1 receptor antagonist (IL-1ra), adiponectin, proinflammatory cytokines IL-1 beta, IL-6, and CCL2, and tumor necrosis factor-alpha with beta-cell function, metabolic status, and clinical remission in patients with recent-onset type 1 diabetes.. Serum was obtained from 256 newly diagnosed patients (122 males and 134 females, median age 9.6 years). Stimulated C-peptide, blood glucose, and A1C were determined in addition to circulating concentration of cytokines at 1, 6, and 12 months after diagnosis. Analyses were adjusted for sex, age, and BMI percentile.. Anti-inflammatory IL-1ra was positively associated with C-peptide after 6 (P = 0.0009) and 12 (P = 0.009) months. The beneficial association of IL-1ra on beta-cell function was complemented by the negative association of IL-1 beta with C-peptide after 1 month (P = 0.009). In contrast, anti-inflammatory adiponectin was elevated in patients with poor metabolic control after 6 and 12 months (P < 0.05) and positively correlated with A1C after 1 month (P = 0.0004). Proinflammatory IL-6 was elevated in patients with good metabolic control after 1 month (P = 0.009) and showed a positive association with blood glucose disposal after 12 months (P = 0.047).. IL-1ra is associated with preserved beta-cell capacity in type 1 diabetes. This novel finding indicates that administration of IL-1ra, successfully improving beta-cell function in type 2 diabetes, may also be a new therapeutic approach in type 1 diabetes. The relation of adiponectin and IL-6 with remission and metabolic status transfers observations from in vitro and animal models into the human situation in vivo. Topics: Adiponectin; Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Cytokines; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Infant; Interleukin-1 Receptor Accessory Protein; Longitudinal Studies; Male | 2008 |
Comparison of pancreas-transplanted type 1 diabetic patients with portal-venous versus systemic-venous graft drainage: impact on glucose regulatory hormones and the growth hormone/insulin-like growth factor-I axis.
Pancreas grafts can be drained through the iliac vein (systemic drainage) or the portal vein.. We hypothesized that normalization of portal insulin in patients with portal pancreas graft drainage stimulates the GH/IGF-I axis and thereby contributes to glucose control.. We compared patients after combined kidney and pancreas transplantation with portal drainage (n = 7) to patients with systemic drainage of the pancreas graft (n = 8) and nondiabetic controls (n = 8). Overnight fasting sera were analyzed for free and total IGF-I and IGF-binding proteins. Glucose regulatory hormones were examined after an oral glucose tolerance test and GH after stimulation with GHRH.. Systemic drainage led to higher basal and stimulated insulin levels than portal drainage (P < 0.05), but increments in response to oral glucose were reduced in both transplanted groups (P < 0.05 vs. controls). However, glucose tolerance was similar in all groups. Circulating free and total IGF-I and IGF-binding protein-3 were similar to control levels in the systemic drainage group but elevated in the portal drainage group (P < 0.05). Consistently, the GH response was reduced in the portal drainage group (P < 0.05 vs. controls) and correlated inversely with free IGF-I (r = -0.63, P < 0.05).. Portal drainage of pancreatic endocrine secretion in pancreas graft recipients raises IGF-I and lowers GH secretion. These changes might explain that glucose regulation is maintained despite lower peripheral insulin levels, compared with patients with systemic graft drainage and nondiabetic control subjects. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Drainage; Female; Glucagon; Glucose Tolerance Test; Human Growth Hormone; Humans; Insulin; Insulin-Like Growth Factor Binding Protein 3; Insulin-Like Growth Factor I; Male; Middle Aged; Pancreas Transplantation; Portal Vein | 2008 |
Anti-thyroid peroxidase antibody, IA-2 antibody, and fasting C-peptide levels predict beta cell failure in patients with latent autoimmune diabetes in adults (LADA)--a 5-year follow-up of the Ehime study.
To clarify the natural course and factors involved in beta cell failure in Japanese latent autoimmune diabetes in adults (LADA) patients.. Insulin secretion in 57 LADA patients identified from among 4980 adult-onset diabetic patients in a hospital-based Ehime study were examined over a 5-year period. Postprandial serum C-peptide levels below 0.33 nmol/l were defined as beta cell failure. The involvement of clinical and immunological factors in the progression to beta cell failure were evaluated.. Forty-two of the fifty-seven LADA patients completed the 5-year follow-up. Eleven (26.2%) required insulin treatment and five (11.9%) progressed to beta cell failure. A Cox regression analysis revealed that positive anti-thyroid peroxidase antibody (TPOAb) and insulinoma-associated protein 2 (IA-2Ab) were associated with the need for insulin treatment (p<0.05 and p<0.01, respectively). Positive TPOAb, anti-thyroglobulin antibody (TGAb), IA-2 antibody (p<0.01 for each), and lower serum fasting C-peptide levels (p<0.05) were contributors to the progression to beta cell failure. Involvement of type 1 diabetes susceptible HLA class II genes was not evident.. Japanese LADA patients are a heterogeneous population. In addition to IA-2 antibody, presence of TPOAb and fasting C-peptide level could indicate an oncoming deterioration of beta cell function. Topics: Adult; Aged; Asian People; Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Genetic Predisposition to Disease; Haplotypes; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Iodide Peroxidase; Male; Middle Aged; Predictive Value of Tests; Prospective Studies; Risk Factors | 2008 |
Incidence of children with slowly progressive form of type 1 diabetes detected by the urine glucose screening at schools in the Tokyo Metropolitan Area.
We investigated the incidence of the slowly progressive form of type 1 diabetes (SPT1D) detected by the urine glucose-screening tests at schools in the Tokyo Metropolitan Area from 1974 to 2004. During this study period, a total of 9,242,259 school students underwent the screening program. Of them, 54 children, 19 males and 35 females, aged 11.6+/-2.4 years, were diagnosed to have SPT1D by this method. The overall incidence of SPT1D was 0.57/100,000/year, which was about one fifth of that of type 2 diabetes detected by the same method. The incidence was significantly higher in junior high school students than in primary school students (0.32 vs. 1.13/100,000/year, p<0.0001). SPT1D accounts for one third of all pediatric cases of type 1 diabetes in Japan, showing that this clinical form is not rare in Japan. There were no significant changes in the incidence of SPT1D during the study period. The incidence of type 1 diabetes in Japanese children is quite low in comparison with Caucasian populations. This incidence, regardless of the clinical form of the disease, does not seem to be influenced by environmental factors in contrast with that of type 2 diabetes. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycosuria; Humans; Incidence; Male; Mass Screening; Schools; Tokyo | 2008 |
Do pretransplant C-peptide levels influence outcomes in simultaneous kidney-pancreas transplantation?
To analyze outcomes in simultaneous kidney-pancreas transplantation (SKPT) recipients who retain C-peptide production at the time of SKPT.. This retrospective analysis of SKPTs from January 2002 through January 2007 compared outcomes between patients with absent or low C-peptide levels (<2.0 ng/mL, group A) with those having levels > or =2.0 ng/mL (group B).. Among 74 SKPTs, 67 were in group A and seven in group B (mean C-peptide level 5.7 ng/mL). During transplantation, group B subjects were older (mean age 51 vs 41 years, P = .006); showed a later age of onset of diabetes (median 35 vs 13 years, P = .0001); weighed more (median 77 vs 66 kg, P = .24); had a greater proportion of African-Americans (57% vs 13%, P = .004); and had a longer pretransplant duration of dialysis (median 40 vs 14 months, P = .14). With similar median follow-up of 40 months, death-censored kidney (95% group A vs 100% group B, P = NS) and pancreas (87% group A vs 100% group B, P = NS) graft survival rates were similar, but patient survival (94% group A vs 71% group B, P = .03) was greater in group A. At 1-year follow-up, there were no significant differences in rejection episodes, surgical complications, infections, readmissions, hemoglobin A1C or C-peptide levels, serum creatinine, or MDRD GFR levels.. Diabetic patients with measurable C-peptide levels before transplant were older, overweight, more frequently African-American and had a later age of onset of diabetes, longer duration of pretransplant dialysis, and reduced patient survival compared to insulinopenic patients undergoing SKPT. The other outcomes were similar. Topics: Adult; Age of Onset; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Histocompatibility Testing; Humans; Kidney Transplantation; Middle Aged; Pancreas Transplantation; Predictive Value of Tests; Preoperative Care; Retrospective Studies; Time Factors; Treatment Outcome; Waiting Lists | 2008 |
Effect of oral amino acids on counterregulatory responses and cognitive function during insulin-induced hypoglycemia in nondiabetic and type 1 diabetic people.
Amino acids stimulate glucagon responses to hypoglycemia and may be utilized by the brain. The aim of this study was to assess the responses to hypoglycemia in nondiabetic and type 1 diabetic subjects after ingestion of an amino acid mixture.. Ten nondiabetic and 10 diabetic type 1 subjects were studied on three different occasions during intravenous insulin (2 mU . kg(-1) . min(-1)) plus variable glucose for 160 min. In two studies, clamped hypoglycemia (47 mg/dl plasma glucose for 40 min) was induced and either oral placebo or an amino acid mixture (42 g) was given at 30 min. In the third study, amino acids were given, but euglycemia was maintained.. Plasma glucose and insulin were no different in the hypoglycemia studies with both placebo and amino acids (P > 0.2). After the amino acid mixture, plasma amino acid concentrations increased to levels observed after a mixed meal (2.4 +/- 0.13 vs. placebo study 1.7 +/- 0.1 mmol/l, P = 0.02). During clamped euglycemia, ingestion of amino acids resulted in transient increases in glucagon concentrations, which returned to basal by the end of the study. During clamped hypoglycemia, glucagon response was sustained and increased more in amino acid studies versus placebo in nondiabetic and diabetic subjects (P < 0.05), but other counter-regulatory hormones and total symptom score were not different. Beta-OH-butyrate was less suppressed after amino acids (200 +/- 15 vs. 93 +/- 9 micromol/l, P = 0.01). Among the cognitive tests administered, the following indicated less deterioration after amino acids than placebo: Trail-Making part B, PASAT (Paced Auditory Serial Addition Test) (2 s), digit span forward, Stroop colored words, and verbal memory tests for nondiabetic subjects; and Trail-Making part B, digit span backward, and Stroop color tests for diabetic subjects.. Oral amino acids improve cognitive function in response to hypoglycemia and enhance the response of glucagon in nondiabetic and diabetic subjects. Topics: Administration, Oral; Adult; Amino Acids; Area Under Curve; Blood Glucose; C-Peptide; Cognition; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Glucose Clamp Technique; Humans; Hydrocortisone; Hypoglycemia; Hypoglycemic Agents; Insulin; Male; Norepinephrine; Pancreatic Polypeptide; Reference Values; Surveys and Questionnaires; Trail Making Test | 2008 |
Relation of circulating concentrations of chemokine receptor CCR5 ligands to C-peptide, proinsulin and HbA1c and disease progression in type 1 diabetes.
Th1 related chemokines CCL3 and CCL5 and Th2 related CCL4 as ligands of the receptor CCR5 contribute to disease development in animal models of type 1 diabetes. In humans, no data are available addressing the role of these chemokines regarding disease progression and remission. We investigated longitudinally circulating concentrations of CCR5 ligands of 256 newly diagnosed patients with type 1 diabetes. CCR5 ligands were differentially associated with beta-cell function and clinical remission. CCL5 was decreased in remitters and positively associated with HbA1c suggestive of a Th1 associated progression of the disease. Likewise, CCL3 was negatively related to C-peptide and positively associated with the beta-cell stress marker proinsulin but increased in remitters. CCL4 associated with decreased beta-cell stress shown by negative association with proinsulin. Blockage of chemokines or antagonism of CCR5 by therapeutic agents such as maraviroc may provide a new therapeutic target to ameliorate disease progression in type 1 diabetes. Topics: Adolescent; Biomarkers; C-Peptide; Chemokine CCL3; Chemokine CCL4; Chemokine CCL5; Chemokines; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Progression; Enzyme-Linked Immunosorbent Assay; Female; Glycated Hemoglobin; Humans; Infant; Male; Proinsulin; Receptors, CCR5 | 2008 |
Fulminant type 1 diabetes as a model of nature to explore the role of C-peptide.
Patients with fulminant type 1 diabetes almost completely lack C-peptide even soon after the onset of the disease, and the deficiency continues for the rest of their life. Thus, fulminant type 1 diabetes could serve as a good model of nature to explore the physiological role of C-peptide. For example, patients with fulminant type 1 diabetes have diabetic chronic complications more frequently than those with classical autoimmune type 1 diabetes 5 years after the onset of diabetes, and the higher prevalence could be partly attributable to the complete lack of C-peptide in fulminant type 1 diabetes. Topics: Biomarkers; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Humans; Insulin; Insulin Secretion | 2008 |
C-peptide and its C-terminal fragments improve erythrocyte deformability in type 1 diabetes patients.
Data now indicate that proinsulin C-peptide exerts important physiological effects and shows the characteristics of an endogenous peptide hormone. This study aimed to investigate the influence of C-peptide and fragments thereof on erythrocyte deformability and to elucidate the relevant signal transduction pathway.. Blood samples from 23 patients with type 1 diabetes and 15 matched healthy controls were incubated with 6.6 nM of either human C-peptide, C-terminal hexapeptide, C-terminal pentapeptide, a middle fragment comprising residues 11-19 of C-peptide, or randomly scrambled C-peptide. Furthermore, red blood cells from 7 patients were incubated with C-peptide, penta- and hexapeptides with/without addition of ouabain, EDTA, or pertussis toxin. Erythrocyte deformability was measured using a laser diffractoscope in the shear stress range 0.3-60 Pa.. Erythrocyte deformability was impaired by 18-25% in type 1 diabetic patients compared to matched controls in the physiological shear stress range 0.6-12 Pa (P < .01-.001). C-peptide, penta- and hexapeptide all significantly improved the impaired erythrocyte deformability of type 1 diabetic patients, while the middle fragment and scrambled C-peptide had no detectable effect. Treatment of erythrocytes with ouabain or EDTA completely abolished the C-peptide, penta- and hexapeptide effects. Pertussis toxin in itself significantly increased erythrocyte deformability.. C-peptide and its C-terminal fragments are equally effective in improving erythrocyte deformability in type 1 diabetes. The C-terminal residues of C-peptide are causally involved in this effect. The signal transduction pathway is Ca(2+)-dependent and involves activation of red blood cell Na(+), K(+)-ATPase. Topics: Adult; C-Peptide; Calcium; Case-Control Studies; Chelating Agents; Diabetes Mellitus, Type 1; Edetic Acid; Enzyme Inhibitors; Erythrocyte Deformability; Erythrocytes; Female; Hemorheology; Humans; Male; Ouabain; Peptide Fragments; Pertussis Toxin; Protein Structure, Tertiary; Signal Transduction; Sodium-Potassium-Exchanging ATPase; Stress, Mechanical | 2008 |
C-peptide improves neuropathy in type 1 diabetic BB/Wor-rats.
The spontaneously diabetic BB/Wor-rat is a close model of human type 1 diabetes and develops diabetic polyneuropathy (DPN) similar to that seen in type 1 patients. Here we examine the therapeutic effects of C-peptide, delivered as continuous infusion or once daily subcutaneous injections on established DPN.. Diabetic rats were treated from four to seven months duration of diabetes with full continuous replacement dose of rat C-peptide via (a) osmopumps (OS), (b) full replacement dose (HSC) or (c) one-third of full replacement dose (LSC) by once daily injections.. Diabetic rats treated with OS showed improvements in motor nerve conduction velocity (p < 0.001), sural nerve myelinated fibre number (p < 0.005), size (p < 0.05), axonal area (p < 0.001), regeneration (p < 0.001) and overall neuropathy score (p < 0.001). The progressive decline in sensory nerve conduction velocity was fully prevented. The frequencies of Wallerian degeneration were decreased (p < 0.005). HSC-treated rats showed prevention of further progression of DPN (p < 0.001), whereas LSC-treated rats showed a milder progression of DPN (p < 0.001) compared to untreated rats as assessed by neuropathy score.. We conclude that (1) C-peptide is effective in the treatment of established DPN, (2) its effect is dose-dependent and (3) replacement by continuous infusion is the most effective administration of C-peptide. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Infusion Pumps; Injections, Subcutaneous; Male; Motor Neurons; Nerve Fibers; Nerve Fibers, Myelinated; Neural Conduction; Neurons, Afferent; Rats; Rats, Inbred BB | 2007 |
Effect of the amino acid alanine on glucagon secretion in non-diabetic and type 1 diabetic subjects during hyperinsulinaemic euglycaemia, hypoglycaemia and post-hypoglycaemic hyperglycaemia.
The aim of our study was to establish whether the well-known defective or absent secretion of glucagon in type 1 diabetes in response to hypoglycaemia is selective or includes lack of responses to other stimuli, such as amino acids.. Responses of glucagon to hypoglycaemia were measured in eight patients with type 1 diabetes and six non-diabetic subjects during hyperinsulinaemic (insulin infusion 0.5 mU kg(-1) min(-1)) and eu-, hypo- and hyperglycaemic clamp studies (sequential steps of plasma glucose 5.0, 2.9, 5.0, 10 mmol/l). Subjects were studied on three randomised occasions with infusion of low- or high-dose alanine, or saline.. With saline, glucagon increased in hypoglycaemia in non-diabetic subjects but not in diabetic subjects. Glucagon increased further with low-dose (181 +/- 16 ng l(-1) min(-1)) and high-dose alanine (238 +/- 20 ng l(-1) min(-1)) in non-diabetic subjects, but only with high-dose alanine in diabetic subjects (area under curve 112 +/- 5 ng l(-1) min(-1)). The alanine-induced glucagon increase in diabetic subjects paralleled the spontaneous glucagon response to hypoglycaemia in non-diabetic subjects not receiving alanine. The greater responses of glucagon to hypoglycaemia with alanine infusion were offset by recovery of eu- or hyperglycaemia.. In type 1 diabetes, the usually deficient responses of glucagon to hypoglycaemia may improve after increasing the concentration of plasma amino acids. Amino acid-enhanced secretion of glucagon in response to hypoglycaemia remains under physiological control since it is regulated primarily by the ambient plasma glucose concentration. These findings might be relevant to improving counter-regulatory defences against insulin-induced hypoglycaemia in type 1 diabetes. Topics: Adolescent; Adult; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Glucose Clamp Technique; Homeostasis; Humans; Hyperglycemia; Hypoglycemia; Male; Middle Aged; Norepinephrine; Reference Values | 2007 |
Increasing the accuracy of oral glucose tolerance testing and extending its application to individuals with normal glucose tolerance for the prediction of type 1 diabetes: the Diabetes Prevention Trial-Type 1.
We assessed the extent to which both standard and alternative indexes from 2-h oral glucose tolerance testing predict type 1 diabetes and whether oral glucose tolerance tests (OGTTs) predict type 1 diabetes in individuals with normal glucose tolerance.. The prediction of type 1 diabetes from baseline OGTTs was studied in 704 Diabetes Prevention Trial-Type 1 participants (islet-cell autoantibody [ICA]-positive relatives of type 1 diabetic patients). The maximum follow-up was 7.4 years. Analyses utilized receiver-operator curves (ROCs), proportional hazards models, and survival curves.. ROC areas under the curve (ROCAUCs) for both the AUC glucose (0.73 +/- 0.02) and an OGTT prediction index (0.78 +/- 0.02) were higher (P < 0.001) than those for the fasting (0.53 +/- 0.02) and 2-h glucose (0.66 +/- 0.02). ROCAUCs for the 60- and 90-min glucose (0.71 +/- 0.02 and 0.72 +/- 0.02, respectively) were also higher (P < 0.01) than those for the fasting and 2-h glucose. Among individuals with normal glucose tolerance, OGTTs were highly predictive, with 4th versus 1st quartile hazard ratios for the 2-h glucose, AUC glucose, and OGTT prediction index ranging from 3.77 to 5.30 (P < 0.001 for all).. Certain alternative OGTT indexes appear to better predict type 1 diabetes than standard OGTT indexes in ICA-positive relatives of type 1 diabetic patients. Moreover, even among those with normal glucose tolerance, OGTTs are strongly predictive. This suggests that subtle metabolic abnormalities are present several years before the diagnosis of type 1 diabetes. Topics: Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Intolerance; Glucose Tolerance Test; Humans; Predictive Value of Tests; Proportional Hazards Models; Reference Values; Reproducibility of Results; Risk Assessment; ROC Curve; Sensitivity and Specificity; Time Factors | 2007 |
Serum interleukin-18 levels are increased and closely associated with various soluble adhesion molecule levels in type 1 diabetic patients.
Topics: Adult; Albuminuria; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Intercellular Adhesion Molecule-1; Interleukin-18; Male; Vascular Cell Adhesion Molecule-1 | 2007 |
An IGF-I gene polymorphism modifies the risk of developing persistent microalbuminuria in type 1 diabetes.
Derangements of the GH-IGF-I axis have been associated with microalbuminuria (MA) in type 1 diabetes. The aim of this study was to investigate whether an IGF-I gene promoter polymorphism influenced the development of persistent MA in type 1 diabetes.. A prospective follow-up study of a cohort of 277 patients with newly diagnosed type 1 diabetes consecutively enrolled between September 1979 and August 1984.. Urinary albumin excretion rate over 24 h was measured in each patient at least once a year. Persistent MA was defined as a urinary albumin excretion rate between 30 and 300 mg/24 h.. During a median follow-up of 18.0 years (range 1.0-21.5), 79 of 277 patients developed persistent MA. IGF-I gene genotype was available for 216 subjects; in 73% of the subjects, the wild-type genotype of this IGF-I gene polymorphism was present, while 27% had the variant type. At baseline, there were no differences in IGF-I levels and HbA(1c) values between subjects with the wild type and subjects with variant type. By Kaplan-Meier analysis, subjects with the variant type of this polymorphism had during follow-up a higher risk of development of MA compared subjects with the wild type (P = 0.03).. Subjects with the variant type of an IGF-I gene polymorphism had a significantly increased risk of developing MA. This risk was not mediated through changes in circulating IGF-I levels. Our study suggests that in type 1 diabetes, this IGF-I gene polymorphism is a risk factor of MA. Topics: Adolescent; Adult; Albuminuria; Alleles; Blood Pressure; C-Peptide; Child; Child, Preschool; Diabetes Complications; Diabetes Mellitus, Type 1; DNA; Female; Gene Frequency; Genotype; Humans; Infant; Insulin-Like Growth Factor I; Male; Polymorphism, Genetic; Promoter Regions, Genetic; Risk | 2007 |
C-peptide is a bioactive peptide.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Glomerular Filtration Rate; Humans; Insulin; Models, Biological | 2007 |
High T-helper-1 cytokines but low T-helper-3 cytokines, inflammatory cytokines and chemokines in children with high risk of developing type 1 diabetes.
Type 1 diabetes (T1D) is suggested to be of T-helper (Th)1-like origin. However, recent reports indicate a diminished interferon (IFN)-gamma secretion at the onset of the disease. We hypothesize that there is a discrepancy in subsets of Th-cells between children with a high risk of developing T1D, children newly diagnosed with T1D and healthy children.. Peripheral blood mononuclear cells (PBMC) were collected from children at high risk for T1D (islet cells antibodies [ICA] >/= 20 IJDF-U), those newly diagnosed and healthy children carrying the HLA-risk gene DQB1*0302 or DQB1*0201 and DQA1*0501. Th1- (IFN-gamma, tumour necrosis factor [TNF]-beta, interleukin [IL]-2), Th2- (IL-4,-5,-13), Th3- (transforming growth factor [TGF-beta], IL-10) and inflammatory associated cytokines (TNF-alpha, IL-1alpha,-6) and chemokines (monocyte chemoattractant protein [MCP]-1,-2,-3, Monokine unregulated by IFN-gamma [MIG], Regulated on Activation, Normal T-cell Expressed and Secreted [RANTES], IL-7,-8,-15) were detected in cell-culture supernatants of PBMC, stimulated with glutamic acid decarboxylase 65 (GAD(65)) and phytohaemagglutinin (PHA), by protein micro array and enzyme linked immunospot (ELISPOT) technique.. The Th1 cytokines IFN-gamma and TNF-beta, secreted both spontaneously and by GAD(65)- and mitogen stimulation, were seen to a higher extent in high-risk children than in children newly diagnosed with T1D. In contrast, TNF-alpha and IL-6, classified as inflammatory cytokines, the chemokines RANTES, MCP-1 and IL-7 as well as the Th3 cytokines TGF-beta and IL-10 were elevated in T1D children compared to high-risk children.. High Th-1 cytokines were observed in children with high risk of developing TID, whereas in children newly diagnosed with T1D Th3 cytokines, inflammatory cytokines and chemokines were increased. Thus, an inverse relation between Th1-like cells and markers of inflammation was shown between children with high risk and those newly diagnosed with T1D. Topics: Adolescent; Biomarkers; C-Peptide; Chemokines; Child; Cytokines; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Humans; Inflammation Mediators; Male; T-Lymphocytes, Regulatory; Th1 Cells | 2007 |
Relationship between gestational diabetes mellitus and type 2 diabetes: evidence of mitochondrial dysfunction.
We examined the pathogenesis of gestational diabetes mellitus (GDM) in a large Dutch multiethnic cohort.. We used a 2-step testing procedure to stratify 2031 consecutive pregnant women into 4 groups according to American Diabetes Association criteria: (a) normal glucose tolerance (NGT), (b) mild gestational hyperglycemia (MGH), (c) GDM without early postpartum diabetes within 6 months of delivery (GDM1), and (d) GDM with early postpartum diabetes (GDM2). Antepartum and postpartum clinical characteristics and measures of glucose tolerance were documented.. Overall, 1627 women had NGT, 237 had MGH, 156 had GDM1, and 11 had GDM2. Prepregnancy body mass index values progressively increased from NGT to MGH to GDM1. The fasting plasma glucose concentration, the 100-g oral glucose tolerance test (OGTT) area under the curve, and the mean glucose concentration during the OGTT all increased progressively among the 4 groups. The fasting C-peptide concentration displayed an inverted-U pattern, with a maximum at a mean plasma glucose concentration during the OGTT of 9.6 mmol/L in the transition from GDM1 to GDM2. The fasting C-peptide/glucose concentration ratio decreased by 42% in GDM patients compared with NGT patients, whereas the ratios in MGH and NGT women were similar.. Progressive metabolic derangement of glucose tolerance 1st detected during pregnancy mimics the pathogenesis of type 2 diabetes. In addition, our results imply an impaired basal glucose effectiveness in the early prediabetic state. To explain the parallel in both metabolic derangements, we postulate that GDM, like type 2 diabetes, is attributable to the same inherited mitochondrial dysfunction. Topics: Adult; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Glucose Tolerance Test; Humans; Mitochondria; Netherlands; Pregnancy | 2007 |
Reversal of defective glucagon responses to hypoglycemia in insulin-dependent autoimmune diabetic BB rats.
The intraislet insulin hypothesis has been proposed to explain absent glucagon responses to hypoglycemia. Recently we directly confirmed this hypothesis by restoring glucagon secretion via provision of a pancreatic artery insulin infusion, which was switched off at the time of hypoglycemia in Wistar rats made diabetic by streptozotocin. The current study examined this hypothesis in a model of spontaneous, autoimmune diabetes, the insulin-dependent diabetic BB rat. The insulin switch-off signal restored the defective glucagon responses to hypoglycemia. However, the magnitude of the restored response was markedly less than that observed in control nondiabetic BB rats (4- to 5-month-old diabetic BB rats = 147 +/- 27; 2-month-old nondiabetic BB rats = 1038 +/- 112 pg/ml, peak delta; P < 0.0001). Because time was required for the BB rat to spontaneously develop diabetes, we asked whether the incomplete restoration of the glucagon response might be related to the animals' growth and development. This led us to compare the glucagon response to hypoglycemia in nondiabetic BB and Wistar rats at 2 and 4-5 months of age. We observed age-related deterioration of not only glucose tolerance and insulin sensitivity but also glucagon responses to hypoglycemia in both strains. There was no significant difference between the glucagon responses to hypoglycemia in age-matched nondiabetic BB rats and diabetic BB rats provided with the insulin switch-off signal. We conclude that defective glucagon responses to hypoglycemia in BB rats can be corrected by restoring regulation of alpha-cell function by insulin. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Hypoglycemia; Insulin; Male; Rats; Rats, Inbred BB; Rats, Wistar | 2007 |
Live encapsulated porcine islets from a type 1 diabetic patient 9.5 yr after xenotransplantation.
The long-term viability and function of transplanted encapsulated neonatal porcine islets was examined in a diabetic patient.. A 41-yr-old Caucasian male with type 1 diabetes for 18 yr was given an intraperitoneal transplant of alginate-encapsulated porcine islets at the dose of 15,000 islet equivalents (IEQs)/kg bodyweight (total dose 1,305,000 IEQs) via laparoscopy. By 12 weeks following the transplant, his insulin dose was significantly reduced by 30% (P = 0.0001 by multiple regression tests) from 53 units daily prior to transplant. The insulin dose returned to the pre-transplant level at week 49. Improvement in glycaemic control continued as reflected by total glycated haemoglobin of 7.8% at 14 months from a pre-transplant level of 9.3%. Urinary porcine C-peptide peaked at 4 months (9.5 ng/ml) and remained detectable for 11 months (0.6 ng/ml). The patient was followed as part of a long-term microbiologic monitoring programme which subsequently showed no evidence of porcine viral or retroviral infection. At laparoscopy 9.5 yr after transplantation, abundant nodules were seen throughout the peritoneum. Biopsies of the nodules showed opacified capsules containing cell clusters that stained as live cells under fluorescence microscopy. Immunohistology noted sparse insulin and moderate glucagon staining cells. The retrieved capsules produced a small amount of insulin when placed in high glucose concentrations in vitro. An oral glucose tolerance test induced a small rise in serum of immuno-reactive insulin, identified as porcine by reversed phase high pressure liquid chromatography.. This form of xenotransplantation treatment has the potential for sustained benefit in human type 1 diabetics. Topics: Adult; Animals; C-Peptide; Cell Survival; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Pregnancy; Swine; Time Factors; Transplantation, Heterologous; Treatment Outcome | 2007 |
Changes in depressive symptoms and glycemic control in diabetes mellitus.
To investigate if changes in depressive symptoms would be associated with changes in glycemic control over a 12-month period in patients with Type 1 and Type 2 diabetes.. Ninety (Type 1 diabetes, n = 28; Type 2 diabetes, n = 62) patients having Beck Depression Inventory (BDI) levels of >10 were enrolled in the study. Of those 90 patients, 65 patients completed a 12-week cognitive behavioral therapy intervention. BDI was assessed at baseline and thereafter biweekly during 12 months. Hemoglobin (HbA1c) and fasting blood glucose levels were assessed at baseline and at four quarterly in-hospital follow-up visits. Linear mixed-model analysis was applied to determine the effects of time and diabetes type on depressive symptoms, HbA1c levels, and fasting glucose levels.. Mean and standard deviation baseline BDI and HbA1c levels were 17.9 +/- 5.8 and 7.6 +/- 1.6, respectively, with no significant difference between patients with Type 1 and Type 2 diabetes. Mixed-model regression analysis found no difference between the groups with Type 1 and Type 2 diabetes in the within-subject effect of BDI score on HbA1c or fasting glucose levels during the study. Depressive symptoms decreased significantly (p = .0001) and similarly over a 12-month period in both patients with Type 1 and Type 2 diabetes, whereas HbA1c and fasting glucose levels did not change significantly over time in either group.. Changes in depressive symptoms were not associated with changes in HbA1c or fasting glucose levels over a 1-year period in either patients with Type 1 or Type 2 diabetes. Topics: Adult; Aged; Blood Glucose; Body Mass Index; C-Peptide; Cognitive Behavioral Therapy; Combined Modality Therapy; Depression; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diet Records; Diet, Diabetic; Energy Intake; Exercise Therapy; Fasting; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Personality Inventory; Prospective Studies; Self Care | 2007 |
[Do we need to diagnosis Latent Autoimmune Diabetes in Adults (LADA)?].
Topics: Adult; Autoantibodies; Autoimmune Diseases; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Immunologic Factors | 2007 |
Distinguishing type 1 and type 2 diabetes at diagnosis. What is the problem?
Topics: Adolescent; Adult; C-Peptide; Carbon Dioxide; Child; Child, Preschool; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Humans; Insulin-Like Growth Factor Binding Protein 1; Ketones; Male; Middle Aged | 2007 |
T-cell responses to islet antigens improves detection of autoimmune diabetes and identifies patients with more severe beta-cell lesions in phenotypic type 2 diabetes.
Latent autoimmune diabetes in adults or type 1.5 diabetes is considered to be a T-cell-mediated autoimmune disease. However, identification of patients is based commonly on autoantibody (Ab) detection. To determine whether measuring T-cell reactivity to islet proteins compared with measuring Abs improves detection of autoimmune diabetes and how beta-cell function correlates with T-cell reactivity compared with Ab positivity, we assessed the T-cell proliferative responses and Ab responses (islet cell autoantibodies, insulin autoantibodies, insulinoma-associated protein-2 autoantibodies, and GAD Abs) to islet proteins of 36 phenotypic type 2 diabetic patients. To be considered Ab(+) or T-cell(+), patients were required to be positive for a minimum of two consecutive time points. beta-Cell function was measured with fasting and glucagon-stimulated C-peptide. Independent of T-cell reactivity, Ab(+) and Ab(-) patients had comparable fasting and glucagon-stimulated C-peptide. Independent of Ab status, T-cell(+) patients demonstrated significantly lower glucagon-stimulated (P < 0.003) C-peptide compared with T-cell(-) patients. These data suggest that measuring T-cell responses to multiple islet proteins in phenotypic type 2 diabetic patients improves identification of patients with autoimmune diabetes and delineates those who have a more severe beta-cell lesion compared with Ab assessment alone. Topics: Adult; Aged; Antigens; Autoantibodies; C-Peptide; Cell Proliferation; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucagon; Glucose; Humans; Islets of Langerhans; Male; Middle Aged; Phenotype; T-Lymphocytes | 2007 |
Immunological aspects of 'fulminant type 1 diabetes'.
'Fulminant diabetes' has been recognized as a super-acute onset and non-autoimmune type 1 diabetes. To evaluate autoimmunity against pancreatic beta cell in fulminant diabetes, ELISPOT assay was applied to the peripheral blood of these patients. In our ELISPOT system, GAD65-reactive and insulin B9-23-reactive IFN-gamma spots were detected in 46.3 and 26.0% of autoantibody-positive type 1 diabetes. Also, in fulminant type 1 diabetic patients, IFN-gamma spots in response to GAD65 and insulin B9-23 peptide were detected in 69.2 and 25.0%, respectively. These results suggest that anti-beta cell autoimmunity contributes to develop fulminant type 1 diabetes. Fulminant type 1 diabetes is known to have IDDM-resistant HLA DR2 with similar frequency of non-T1D subjects. In a mouse model, when islet-reactive CD8 cells are transferred to young NOD mice, the recipients develop overt diabetes within 1 week with massive insulitis. In (NOD x Balb/c) F1 mice, which hold idd-resistant genes, transfer of islet-reactive CD8 cells induced diabetes to 60% F1 recipients within 1 week with the later disappearance of insulitis. This mouse model shows very similar feathers to fulminant type 1 diabetes; idd-resistant HLA and no insulitis. These results implicated that once anti-islet immunity is optimally activated, subjects with partially resistant alleles could become overt diabetes. Topics: Acute Disease; Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Models, Animal; Humans; Insulin-Secreting Cells; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; T-Lymphocytes | 2007 |
Coefficient of variation of R-R intervals in electrocardiogram is a sensitive marker of anemia induced by autonomic neuropathy in type 1 diabetes.
The present study investigated the relationship between hemoglobin (Hb) levels and autonomic failure using a sensitive marker, coefficient of variation of R-R intervals in electrocardiogram (CVR-R) in order to clarify a cause of normocytic normochromic anemia in type 1 diabetic patients without overt nephropathy. We recruited 46 patients with type 1 diabetes and measured creatinine clearance (Ccr), HbA1c, albuminuria, Hb levels and CVR-R of all patients. In addition, the status of diabetic retinopathy and neuropathy were also evaluated. Serum erythropoietin (EPO), Fe, total iron binding capacity, lactate dehydrogenase, total bilirubin levels and number of reticulocytes and mean corpuscular volume were also measured to distinguish types of anemia. To survey the statistical correlation existing between Hb and body mass index (BMI), Ccr, HbA1c, albuminuria or retinopathy, multiple regression analysis was performed. Serum EPO, Fe, TIBC, LDH and TB levels and number of reticulocytes and MCV were within normal limits. Multiple regression analysis disclosed that HbA1c, nephropathy evaluated by albuminuria and Ccr, and retinopathy has no concern with Hb level. There is only significant relationship between Hb levels and CVR-R. Similar results were obtained even if we analyzed a group of male and female separately. We conclude that CVR-R has the strong relationship on anemia without overt nephropathy in type 1 diabetes, indicating that autonomic failure contributes on the progression of anemia via a poor response of EPO to anemia. Topics: Adult; Aged; Albuminuria; Anemia; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Electrocardiography; Erythropoietin; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Sensitivity and Specificity | 2007 |
[Interleukin 12 as an anti-angiogenic mediator in type 1 diabetic children].
The objective of the study was to analyse levels IL-12 and to relate the findings to the clinical course of type 1 diabetes mellitus (DM1).. We examined a group of 102 children with DM1 and 39 healthy children (as the control). All the children with DM1 had their daily urine albumin excretion, HbA1c, C-peptide measured, 24hrs blood pressure monitoring and ophthalmologic examination. In accordance to the ophthalmologic examination and level IL-12 in the serum the diabetic children were divided into 3 groups: group A: IL-12>0 pg/ml; group B: IL-12=0 pg/ml; group C: IL-12=0 pg/ml and IL12>0 pg/ml. Serum levels of IL-12 and TNFalpha were measured by the immunoenzymatic ELISA method, Quan-tikine High Sensitivity Human by R&D Systems (USA).. Children of group A were characterized by significantly high level of IL-12 and by the absence of TNFalpha as compared with the children of group B, who had undetectable IL-12 along with high TNFalpha level. Additionally, children of group A had significantly lower urine albumin excretion and had only developed retinopathy. However, the children of group B not only had retinopathy, nephropathy but also arterial hypertension. The patients of group A were also analysed against the children of group C, who were characterized by high IL-12 level and some of them had also detectable TNFalpha, but without retinopathy and nephropathy.. The results of our study imply the existence of balance between IL-12 and TNFalpha in type 1 DM children, which seems to warrant the stage of disease without diabetic complications. However, the IL-12 domination tends to prevent or delay nephropathy development but does not protect from retinopathy. Topics: Adolescent; Albuminuria; Angiogenesis Inducing Agents; Angiogenesis Inhibitors; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Hypertension; Interleukin-12; Male; Neovascularization, Pathologic; Reference Values; Tumor Necrosis Factor-alpha | 2007 |
Meal-stimulated glucagon release is associated with postprandial blood glucose level and does not interfere with glycemic control in children and adolescents with new-onset type 1 diabetes.
The role of glucagon in hyperglycemia in type 1 diabetes is unresolved, and in vitro studies suggest that increasing blood glucose might stimulate glucagon secretion.. Our objective was to investigate the relationship between postprandial glucose and glucagon level during the first 12 months after diagnosis of childhood type 1 diabetes.. We conducted a prospective, noninterventional, 12-month follow-up study conducted in 22 centers in 18 countries.. Patients included 257 children and adolescents less than 16 yr old with newly diagnosed type 1 diabetes; 204 completed the 12-month follow-up.. The study was conducted at pediatric outpatient clinics.. We assessed residual beta-cell function (C-peptide), glycosylated hemoglobin (HbA(1c)), blood glucose, glucagon, and glucagon-like peptide-1 (GLP-1) release in response to a 90-min meal stimulation (Boost) at 1, 6, and 12 months after diagnosis.. Compound symmetric repeated-measurements models including all three visits showed that postprandial glucagon increased by 17% during follow-up (P = 0.001). Glucagon levels were highly associated with postprandial blood glucose levels because a 10 mmol/liter increase in blood glucose corresponded to a 20% increase in glucagon release (P = 0.0003). Glucagon levels were also associated with GLP-1 release because a 10% increase in GLP-1 corresponded to a 2% increase in glucagon release (P = 0.0003). Glucagon levels were not associated (coefficient -0.21, P = 0.07) with HbA(1c), adjusted for insulin dose. Immunohistochemical staining confirmed the presence of Kir6.2/SUR1 in human alpha-cells.. Our study supports the recent in vitro data showing a stimulation of glucagon secretion by high glucose levels. Postprandial glucagon levels were not associated with HbA(1c), adjusted for insulin dose, during the first year after onset of childhood type 1 diabetes. Topics: Adolescent; ATP-Binding Cassette Transporters; Blood Glucose; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Eating; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Secreting Cells; Glycated Hemoglobin; Humans; Immunohistochemistry; Insulin-Secreting Cells; Male; Postprandial Period; Potassium Channels; Potassium Channels, Inwardly Rectifying; Receptors, Drug; Sulfonylurea Receptors | 2007 |
The clinical and immunogenetic characteristics of adult-onset type 1 diabetes mellitus in Korea.
Although the HLA class II alleles and immunological abnormalities are associated with type 1 diabetes mellitus (T1DM) in all racial groups, there are considerable variations in the genotypes and the prevalence of autoantibodies. In order to investigate the characteristics of the immunogenetic patterns and to use these as an early diagnostic tool and guideline for a therapeutic plan, we examined the clinical characteristics and the patterns of anti-GAD antibody (GADA), IA-2 antibody (IA-2A), HLA-DR and HLA-DQ in Korean adult-onset T1DM patients. Adult-onset patients had higher serum C-peptide levels than child-onset patients. In adult-onset patients, the prevalence of GADA and IA-2A were 59.5% and 15.3% respectively, and increased frequencies of HLADR4 and-DR9 were found. The frequencies of HLADQA1,-DQB1 and-DQ heterodimers were similar to those of the control, but child-onset patients had high frequencies of the HLA-DR3,-DR4,-DR9, DQA1*0301, DQA1*0501 and DQB1*0201 genotypes. In conclusion, Korean adult-onset T1DM patients had a lower prevalence of GADA, which was comparable to that found in Caucasian patients. The detection of GADA might help to predict the insulin dependency of adult-onset diabetes. Difference in the frequencies of diabetes associated with HLA type suggests that there might be a heterogeneity in the pathogenesis of diabetes according to the age of onset. Topics: Adolescent; Adult; Age of Onset; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Genotype; HLA-DQ Antigens; HLA-DR Antigens; Humans; Immunogenetics; Korea; Male; Middle Aged; Retrospective Studies | 2007 |
Co-localisation of the Kir6.2/SUR1 channel complex with glucagon-like peptide-1 and glucose-dependent insulinotrophic polypeptide expression in human ileal cells and implications for glycaemic control in new onset type 1 diabetes.
The ATP-dependent K+-channel (K(ATP)) is critical for glucose sensing and normal glucagon and insulin secretion from pancreatic endocrine alpha- and beta-cells. Gastrointestinal endocrine L- and K-cells are also glucose-sensing cells secreting glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotrophic polypeptide (GIP) respectively. The aims of this study were to 1) investigate the expression and co-localisation of the K(ATP) channel subunits, Kir6.2 and SUR1, in human L- and K-cells and 2) investigate if a common hyperactive variant of the Kir6.2 subunit, Glu23Lys, exerts a functional impact on glucose-sensing tissues in vivo that may affect the overall glycaemic control in children with new-onset type 1 diabetes.. Western blot and immunohistochemical analyses were performed for expression and co-localisation studies. Meal-stimulated C-peptide test was carried out in 257 children at 1, 6 and 12 months after diagnosis. Genotyping for the Glu23Lys variant was by PCR-restriction fragment length polymorphism.. Kir6.2 and SUR1 co-localise with GLP-1 in L-cells and with GIP in K-cells in human ileum tissue. Children with type 1 diabetes carrying the hyperactive Glu23Lys variant had higher HbA1C at diagnosis (coefficient = 0.61%, P = 0.02) and 1 month after initial insulin therapy (coefficient = 0.30%, P = 0.05), but later disappeared. However, when adjusting HbA1C for the given dose of exogenous insulin, the dose-adjusted HbA1C remained higher throughout the 12 month study period (coefficient = 0.42%, P = 0.03).. Kir6.2 and SUR1 co-localise in the gastrointestinal endocrine L- and K-cells. The hyperactive Glu23Lys variant of the K(ATP) channel subunit Kir6.2 may cause defective glucose sensing in several tissues and impaired glycaemic control in children with type 1 diabetes. Topics: Adolescent; ATP-Binding Cassette Transporters; Blotting, Western; C-Peptide; Child; Diabetes Mellitus, Type 1; Eating; Female; Gastric Inhibitory Polypeptide; Genotype; Glucagon; Glucagon-Like Peptide 1; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Ileum; Immunohistochemistry; Insulin; Islets of Langerhans; Male; Polymorphism, Restriction Fragment Length; Potassium Channels; Potassium Channels, Inwardly Rectifying; Receptors, Drug; Sulfonylurea Receptors | 2007 |
Headache prevalence related to diabetes mellitus. The Head-HUNT study.
In patients with diabetes mellitus (DM), there are changes in vascular reactivity and nerve conduction that may be relevant for migraine pathophysiology. However, previous studies on the relationship between headache and DM have shown conflicting results. The aim of the present study was to investigate a possible association between headache and DM in a large population-based cross-sectional study. Associations were assessed in multivariate analyses, estimating prevalence odds ratios (ORs) with 95% confidence intervals (CIs). Prevalence OR of migraine was lower amongst persons with DM compared with those without DM, the OR being 0.4 (95% CI: 0.2-0.9) for type 1 and 0.7 (95% CI: 0.5-0.9) for type 2 DM. Furthermore, OR of headache were lower amongst those with duration of DM > or = 13 years compared with those who had got DM the last 3 years, OR 0.6 (95% CI: 0.4-0.9). The analyses revealed no clear associations between non-migrainous headache and DM. The reason for the inverse relationship between migraine and DM is unknown, but might be related to pathophysiological abnormalities in patients with DM that protect against migraine. Topics: Adult; Aged; Aged, 80 and over; Autoantibodies; Blood Glucose; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Headache; Humans; Male; Middle Aged; Migraine Disorders; Norway; Odds Ratio; Surveys and Questionnaires | 2007 |
Visualization of early engraftment in clinical islet transplantation by positron-emission tomography.
Topics: Autoradiography; C-Peptide; Diabetes Mellitus, Type 1; Fluorodeoxyglucose F18; Graft Survival; Humans; Islets of Langerhans Transplantation; Liver; Male; Middle Aged; Positron-Emission Tomography; Tomography, X-Ray Computed | 2007 |
Type 2 diabetes in children in the Netherlands: the need for diagnostic protocols.
The worldwide trend towards obesity in childhood is also observed in the Netherlands and one of the consequences may be type 2 diabetes. In this study, we assessed the number of children with type 2 diabetes, diagnosed by paediatricians, in the Netherlands.. In 2003 and 2004 the Dutch Paediatric Surveillance Unit, a nationwide paediatric register, was used to assess new cases of diabetes mellitus. Data on socio-demographic and clinical characteristics were collected by means of a questionnaire. A second questionnaire was sent to the reporting paediatrician if the diagnosis was inconclusive or if the diagnosis was type 1 diabetes in combination with overweight or obesity, according to international criteria.. During the 24 months of registration, the paediatricians reported 1142 new cases of diabetes, 943 of which were eligible for analysis. Initially, 14 patients (1.5%) were reported with type 2 diabetes. Only seven of these patients were classified as type 2 diabetes according to the ADA criteria, as information on C-peptides or antibodies was often missing. Based on clinical characteristics, the other seven patients were very likely to have type 2 diabetes. After the second questionnaire, six more patients met the ADA criteria and two were very likely to have type 2 diabetes. Most of the patients were female (95%), 14% were of Turkish and 18% of Moroccan origin.. This study shows a discrepancy between the number of patients with type 2 diabetes diagnosed by paediatricians in daily practice and diagnosed according to the ADA criteria. Moreover, a considerable amount of reported patients were misclassified. Finally, 2.4% patients were classified as (very likely) type 2 diabetes. The development of programmes and protocols for prevention, diagnosis and classification applicable in daily practice is warranted. Topics: Adolescent; Body Mass Index; Body Weight; C-Peptide; Child; Child, Preschool; Diabetes Complications; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Infant; Infant, Newborn; Male; Morocco; Netherlands; Obesity; Population Surveillance; Sex Factors; Surveys and Questionnaires; Turkey | 2007 |
Editorial: The role of glucagon in postprandial hyperglycemia--the jury's still out.
Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Glucagon-Like Peptide 1; Glucagon-Secreting Cells; Glycated Hemoglobin; Humans; Hyperglycemia; Insulin; Postprandial Period; Potassium Channel Blockers; Potassium Channels, Inwardly Rectifying; Sulfonylurea Compounds | 2007 |
Islet cell autoantibody levels after the diagnosis of young adult diabetic patients.
The aim was to determine the course of islet cell antibodies [glutamate decarboxylase (GADA), tyrosine phosphatase-like islet antigen 2 (IA-2A) and islet cell (ICA)] after the diagnosis of the diabetic patient.. The Diabetes Incidence Study in Sweden (DISS) attempted to prospectively enrol all newly diagnosed diabetic patients aged 15-34 years during 1992 and 1993. C-peptide and autoantibody levels were determined from venous blood samples at diagnosis and again at yearly intervals for 6 years.. After the first year, the odds of remaining GADA positive decreased by 9% per year [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.85-0.96] while the mean GADA index remained unchanged ( = 0.8, P = 0.37). There was no change in the percentage of subjects testing IA-2A positive after the first year ( = 0.1, P = 0.75). However, the mean index decreased 0.04 per year (95% CI: 0.03-0.05)-a 7.9% decline (95% CI: 5.4-10.4%). The odds of a subject testing positive for ICA decreased by 24% per year (OR = 0.76, 95% CI = 0.70-0.82). The mean ICA levels decreased 0.75 per year (95% CI: 0.66-0.84)-a 16.4% decline (95% CI: 14.1-18.6%). The rate of change in titres for all three autoantibodies was independent of gender, human leucocyte antigen genotype and C-peptide status.. GADA levels remained high while ICA levels declined. In contrast to a previous study, we found that the proportion of IA-2A subjects remaining positive did not decrease after the first year, while the average index decreased slightly. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Longitudinal Studies; Male; Odds Ratio; Predictive Value of Tests; Prospective Studies | 2007 |
Specific inhibition of autoimmune T cell transmigration contributes to beta cell functionality and insulin synthesis in non-obese diabetic (NOD) mice.
Human diabetes mellitus (IDDM; type I diabetes) is a T cell-mediated disease that is closely modeled in non-obese diabetic (NOD) mice. The pathogenesis of IDDM involves the transmigration of autoimmune T cells into the pancreatic islets and the subsequent destruction of insulin-producing beta cells. Therapeutic interventions leading to beta cell regeneration and the reversal of established IDDM are exceedingly limited. We report here that specific inhibition of T cell intra-islet transmigration by using a small molecule proteinase inhibitor restores beta cell functionality, increases insulin-producing beta cell mass, and alleviates the severity of IDDM in acutely diabetic NOD mice. As a result, acutely diabetic NOD mice do not require insulin injections for survival for a significant time period, thus providing a promising clue to effect IDDM reversal in humans. The extensive morphometric analyses and the measurements of both the C-peptide blood levels and the proinsulin mRNA levels in the islets support our conclusions. Diabetes transfer experiments suggest that the inhibitor specifically represses the T cell transmigration and homing processes as opposed to causing immunosuppression. Overall, our data provide a rationale for the pharmacological control of the T cell transmigration step in human IDDM. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Immunosuppressive Agents; Insulin; Insulin-Secreting Cells; Matrix Metalloproteinase 14; Matrix Metalloproteinase Inhibitors; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Organic Chemicals; RNA, Messenger; T-Lymphocytes | 2007 |
Evaluation of polyneuropathy markers in type 1 diabetic kidney transplant patients and effects of islet transplantation: neurophysiological and skin biopsy longitudinal analysis.
The purpose of this study was to evaluate whether islet transplantation may stabilize polyneuropathy in uremic type 1 diabetic patients (end-stage renal disease [ESRD] and type 1 diabetes), who received a successful islet-after-kidney transplantation (KI-s).. Eighteen KI-s patients underwent electroneurographic tests of sural, peroneal, ulnar, and median nerves: the nerve conduction velocity (NCV) index and amplitudes of both sensory action potentials (SAPs) and compound motor action potentials (CMAPs) were analyzed longitudinally at 2, 4, and 6 years after islet transplantation. Skin content of advanced glycation end products (AGEs) and expression of their specific receptors (RAGE) were also studied at the 4-year follow-up. Nine patients with ESRD and type 1 diabetes who received kidney transplantation alone (KD) served as control subjects.. The NCV score improved in the KI-s group up to the 4-year time point (P = 0.01 versus baseline) and stabilized 2 years later, whereas the same parameter did not change significantly in the KD group throughout the follow-up period or when a cross-sectional analysis between groups was performed. Either SAP or CMAP amplitudes recovered in the KI-s group, whereas they continued worsening in KD control subjects. AGE and RAGE levels in perineurium and vasa nervorum of skin biopsies were lower in the KI-s than in the KD group (P < 0.01 for RAGE).. Islet transplantation seems to prevent long-term worsening of polyneuropathy in patients with ESRD and type 1 diabetes who receive islets after kidney transplantation. No statistical differences between the two groups were evident on cross-sectional analysis. A reduction in AGE/RAGE expression in the peripheral nervous system was shown in patients receiving islet transplantation. Topics: Adult; Biomarkers; Biopsy; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Electrophysiology; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Longitudinal Studies; Middle Aged; Peripheral Nerves; Skin | 2007 |
Influence of family history of diabetes on incidence and prevalence of latent autoimmune diabetes of the adult: results from the Nord-Trøndelag Health Study.
The aim of this study was to investigate the association between family history of diabetes (FHD) and prevalence and incidence of latent autoimmune diabetes of the adult (LADA), type 1 diabetes, and type 2 diabetes.. The results were based on cross-sectional data from 64,498 men and women (aged >or=20 years) who were in the Nord-Trøndelag Health Study, which included 128 cases of LADA, 1,134 cases of type 2 diabetes, and 123 cases of type 1 diabetes. In addition, prospective data on 46,210 subjects, which included 80 incident cases of LADA, observed between 1984 and 1986 and 1995 and 1997 were available. Patients with LADA had antibodies against GAD and were insulin independent at diagnosis.. FHD was associated with a four times (odds ratio [OR] 3.92 [95% CI 2.76-5.58]) increased prevalence of LADA. Corresponding estimates for type 2 and type 1 diabetes were 4.2 (3.72-4.75) and 2.78 (1.89-4.10), respectively. Patients with LADA who had FHD had lower levels of C-peptide (541 vs. 715 pmol/l) and were more often treated with insulin (47 vs. 31%) than patients without FHD. Prospective data indicated that subjects with siblings who had diabetes had a 2.5 (1.39-4.51) times increased risk of developing LADA during the 11-year follow-up compared with those without.. This study indicates that FHD is a strong risk factor for LADA and that the influence of family history may be mediated through a heritable reduction of insulin secretion. Topics: Adult; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Incidence; Life Style; Male; Medical History Taking; Risk Factors; Siblings; Sweden | 2007 |
[Prediction of clinical remission using the C-peptide level in type 1 diabetes in children].
The aim of the study was to identify individual, clinical and metabolic factors that predict the C-peptide levels and appearance of clinical partial remission during the first year of type 1 diabetes (T1D) in children.. 197 type 1 diabetic patients (84 female and 113 male, mean age 10.4 years) were examined. C-peptide levels were detected by radioimmunoassay at the diagnosis and after 3, 6 and 12 months of the disease.. Median C-peptide level at onset was 0.17 pmol/mL (0.11-0.32), peaked in the 3rd month (0.27 pmol/mL, 0.15-0.43; p<0.001) and declined thereafter - 0.21 pmol/mL (0.1-0.34) in the 6th month and 0.13 pmol/mL (0.05-0.26) at the 12th month of the disease. Logistic regression showed that younger age, low pH and higher HbA1c (glycated haemoglobin) at the onset were associated with the "lower" (<0.28 pmol/mL) C-peptide level at the diagnosis. The presence of clinical partial remission was observed in 31% of children. Patients with remission had higher C-peptide levels observed in the first 6 months of T1D than children without clinical remission. Receiver operating characteristic (ROC) curve method was used for the estimation of the threshold of C-peptide level at the onset for the prediction of the clinical remission during the first year of T1D (0.141 pmol/mL, AUC (95%CI) = 0.608 (0.53-0.68)).. Concluding, higher C-peptide level is associated with the appearance of clinical partial remission during the first six months of T1D. C-peptide level may be a good predictor of the clinical partial remission during the first year of T1D. Topics: Adolescent; Age of Onset; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fasting; Female; Glycated Hemoglobin; Humans; Infant; Male; Prognosis; Radioimmunoassay; Remission, Spontaneous; ROC Curve; Time Factors | 2007 |
Stopping diabetes in its tracks: autologous non-myeloablative stem cell transplantation.
A recent report in this year's April issue of Journal of the American Medical Association describes an unprecedented success in delaying insulin dependence in patients with recent-onset Type 1 diabetes after non-myeloablative immune suppression with cyclophosphamide and antithymocyte globulin followed by autologous stem cell transplantation. In this study, 14 out of 15 patients became insulin-independent, which lasted up to 35 months. Concomitantly, C-peptide levels increased substantially compared with preintervention values. Treatment of autoimmune disorders, and in particular Type 1 diabetes, constitutes a complex balancing act between suppressing autoaggressive responses strongly and permanently enough, while circumventing much-feared long-term side effects from chronic immunosuppression. This clinical Phase I/II trial is relevant to fine-tuning interventive protocols and contributing to the further development of suitable combination therapies to prevent and treat Type 1 diabetes. Topics: Autoantibodies; C-Peptide; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Combined Modality Therapy; Cyclophosphamide; Diabetes Mellitus, Type 1; Follow-Up Studies; Hematopoietic Stem Cell Transplantation; Humans; Immunosuppressive Agents; Models, Biological; Stem Cells; T-Lymphocytes, Regulatory; Time Factors; Transplantation Conditioning; Transplantation, Autologous; Treatment Outcome | 2007 |
Low-risk HLA genotype in Type 1 diabetes is associated with less destruction of pancreatic B-cells 12 months after diagnosis.
The role of human leukocyte antigen (HLA) genes in the susceptibility to Type 1 diabetes (T1DM) is well known. However, we do not know whether the degree of pancreatic B-cell destruction depends on different HLA genetic risk. The aim of this study was to analyse the influence of DRB1* and DQB1* genes on the rate of pancreatic B-cell loss in a prospective series of 120 consecutive newly diagnosed T1DM subjects in the first 12 months after diagnosis.. Patients were typed for HLA-DRB1* and DQB1* loci by a reverse line blot assay using an array of immobilized sequence-specific oligonucleotide probes. C-peptide, insulin requirement and glycated haemoglobin (HbA(1c)) were determined at diagnosis and every 3 months for 12 months. The variance of C-peptide as evidence of B-cell loss during follow-up was analysed using the general linear model for repeated-measures procedure.. Fasting C-peptide in T1DM subjects with low HLA genetic risk was significantly higher when compared with subjects with moderate or high HLA genetic risk from time of diagnosis up to 12 months (P = 0.007 and P = 0.0002, respectively). Nonetheless, the changes in C-peptide levels over a 12-month period did not differ significantly between T1DM subjects with different HLA genetic risks.. Low-risk HLA genotype in T1DM is associated with less destruction of pancreatic B-cells up to 12 months after diagnosis. These results are useful when designing trials for therapies aimed to prevent the progression of B-cell destruction in recent-onset T1DM. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Genetic Predisposition to Disease; Genotype; Glycated Hemoglobin; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Insulin-Secreting Cells; Male | 2007 |
Re: A comparison of classification schemes for ketosis-prone diabetes.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Fasting; Humans; Insulin Resistance | 2007 |
Impact of IDDM2 on disease pathogenesis and progression in children with newly diagnosed type 1 diabetes: reduced insulin antibody titres and preserved beta cell function.
The insulin-dependent diabetes mellitus 2 gene (IDDM2) is a type 1 diabetes susceptibility locus contributed to by the variable number of tandem repeats (VNTR) upstream of the insulin gene (INS). We investigated the association between INS VNTR class III alleles (-23HphIA/T) and both insulin antibody presentation and residual beta cell function during the first year after diagnosis in 257 children with type 1 diabetes.. To estimate C-peptide levels and autoantibody presentation, patients underwent a meal-stimulated C-peptide test 1, 6, and 12 months after diagnosis. The insulin -23HphIA/T variant was used as a marker of class III alleles and genotyped by PCR-RFLP.. The insulin antibody titres at 1 and 6 months were significantly lower in the class III/III and class I/III genotype groups than in the class I/I genotype group (p = 0.01). Class III alleles were also associated with residual beta cell function 12 months after diagnosis and independently of age, sex, BMI, insulin antibody titres, and HLA-risk genotype group (p = 0.03). The C-peptide level was twice as high among class III/III genotypes as in class I/I and class I/III genotypes (319 vs 131 and 166 pmol/l, p=0.01). Furthermore, the class III/III genotype had a 1.1% reduction in HbA(1)c after adjustment for insulin dose (p = 0.04).. These findings suggest a direct connection in vivo between INS VNTR class III alleles, a decreased humoral immune response to insulin, and preservation of beta cell function in recent-onset type 1 diabetes. Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Follow-Up Studies; Genetic Predisposition to Disease; Humans; Insulin; Insulin Antibodies; Insulin-Secreting Cells; Minisatellite Repeats; Polymorphism, Single Nucleotide; Time Factors | 2006 |
Microencapsulated pancreatic islet allografts into nonimmunosuppressed patients with type 1 diabetes: first two cases.
Topics: Blood Glucose; C-Peptide; Capsules; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Immunosuppression Therapy; Islets of Langerhans; Islets of Langerhans Transplantation; Transplantation, Homologous; Treatment Outcome | 2006 |
Isolation and in vitro characterization of pancreatic progenitor cells from the islets of diabetic monkey models.
Recent studies on the identification of stem/progenitor cells within adult mouse and human pancreatic islets have raised the possibility that autologous transplantation might be used in treating type 1 diabetes. However, it is not yet known whether such stem/progenitor cells are impaired in type 1 diabetic patients or diabetic animal models. The latter would also allow us to test the efficacy of autologous transplantation in large animal models prior to clinical applications. The present study aims to determine the existence of stem/progenitor cells in the islets of diabetic monkey models and to assess the proliferation and differentiation potential of such cells in vitro. Our results indicate that there are pancreatic progenitor cells in the adult pancreatic islets in both normal and type 1 diabetic monkeys. The isolated pancreatic progenitor cells can be greatly expanded in culture. Upon the removal of growth medium, these cells spontaneously form islet-like cell clusters, which could be further induced to secrete insulin by inductive factors. Furthermore, the secretion of insulin and C-peptide from the islet-like cell clusters responds to glucose and other stimuli, indicating that the differentiated cells not only resemble beta-cells but also possess the unique biological function of beta-cells. This study provides a foundation for further characterization of adult pancreatic progenitor cells and autologous transplantation using pancreatic progenitor cells in treating diabetic monkeys. Topics: Animals; C-Peptide; Cell Differentiation; Cell Separation; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Glucose; Insulin; Insulin Secretion; Intermediate Filament Proteins; Islets of Langerhans; Macaca fascicularis; Male; Nerve Tissue Proteins; Nestin; Stem Cells | 2006 |
Serum adiponectin is associated with fasting serum C-peptide in non-obese diabetic patients.
Circulating adiponectin (ADP) level in diabetic patients was mainly studied from a viewpoint of insulin action, with little being known about the regulation by pancreatic beta-cell function. We thus investigated the relationship between the serum ADP concentration and pancreatic beta-cell function in non-obese [body mass index (BMI) <30 kg/m(2)] diabetic patients. Serum ADP was measured in 239 type 2 diabetic patients, 61 type 1 diabetic patients and 159 non-obese and non-diabetic subjects with enzyme-linked immunosorbent assay. Serum ADP was analyzed separately by gender. In both males and females, the ADP level increased in conjugation with beta-cell dysfunction, estimated by fasting serum C-peptide, and showed marked increase in type 1 diabetic patients. Multivariate analysis in type 2 diabetic patients showed that the fasting serum C-peptide was extracted as an independent and significantly negative modulator for serum ADP in addition to BMI. The ADP level was not associated with the daily dose of injected insulin in the multivariate analysis using insulin treated patients with types 1 and 2 diabetes. These results indicate that pancreatic beta-cell function is one of a significant negative modulator for the circulating ADP level in non-obese diabetic patients and support the presence of an adipoinsular axis. Topics: Adiponectin; Adiposity; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Insulin-Secreting Cells; Male; Obesity; Regression Analysis; Sex Characteristics; Statistics as Topic | 2006 |
Sex- and season-dependent differences in C-peptide levels at diagnosis of immune-mediated type 1 diabetes.
The incidence of type 1 diabetes varies according to age, sex and season of diagnosis. We investigated whether these and other clinical, biological and anthropometric parameters were correlated with residual beta cell function in newly diagnosed patients, since it is possible that the nature of external and/or genetic disease accelerators may be (partly) reflected in the inaugural disease presentation.. The correlates of random C-peptide levels sampled shortly after diagnosis (median [interquartile range]: 3 [0-14] days) were studied by multivariate analysis in 1,883 islet-antibody-positive diabetic patients aged <40 years who were diagnosed between 1989 and 2000.. Higher C-peptide levels (above percentile 50 of patients) were associated with older age at diagnosis, female sex, diagnosis in the high-incidence season (October to March), less-decreased BMI (expressed as a standard deviation score), lower insulin requirements after stabilisation, lower prevalence of ketonuria and a less-increased glycaemia at diagnosis (all p < 0.001). C-peptide levels were not correlated with calendar year at diagnosis, duration of symptoms prior to diagnosis, HLA-DQ2/DQ8 genotype or islet antibody status.. Sex- and season-dependent differences in residual functional beta cell mass and/or insulin resistance have been identified at diagnosis of type 1 diabetes. They may reflect differences in disease-precipitating external or lifestyle factors and should be further investigated longitudinally in prediabetes to further identify putative aetiological factors, which may provide targets for prevention. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Belgium; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA-DQ Antigens; Humans; Infant; Male; Registries; Sex Characteristics | 2006 |
Increased plasma amylin in type 1 diabetic patients after kidney and pancreas transplantation: A sign of impaired beta-cell function?
In response to hyperglycemia, beta-cells release insulin and C-peptide, as well as islet amyloid pancreatic polypeptide, which is involved in glucose homeostasis. After successful pancreas-kidney transplantation (PKT), type 1 diabetic patients may revert to a nondiabetic metabolism without exogenous insulin therapy and re-secrete all beta-cell hormones.. Using mathematical models, we investigated hormone (amylin, insulin, C-peptide) and metabolite (glucose, free fatty acids) kinetics, beta-cell sensitivity to glucose, and oral glucose insulin sensitivity index (OGIS) in 11 nondiabetic type 1 diabetic patients after PKT (BMI 25 +/- 1 kg/m2, 47 +/- 2 years of age, 4 women/7 men, glucocorticoid-free), 6 matching nondiabetic patients after kidney transplantation (25 +/- 1 kg/m2, 50 +/- 5 years, 3 women/3 men, on glucocorticoids), and 9 matching nondiabetic control subjects (24 +/- 1 kg/m2, 47 +/- 2 years, 4 women/5 men) during a 3-h 75-g oral glucose tolerance test (OGTT).. PKT patients had higher fasting amylin (19 +/- 3 vs. control subjects: 7 +/- 1 pmol/l) and insulin (20 +/- 2 vs. control subjects: 10 +/- 1 microU/ml; each P < 0.01) levels. Kidney transplant subjects showed increased OGTT plasma insulin at 90 min and C-peptide levels (each P < 0.05). In PKT patients, plasma glucose from 90 to 150 min was 9-31% higher (P < 0.05 vs. control subjects). Amylin clearance was comparable in all groups. Amylin's plasma concentrations and area under the concentration curve were up to twofold higher in PKT patients during OGTT (P < 0.05). OGIS was not significantly different between groups. beta-Cell sensitivity to glucose was reduced in PKT patients (-64%, P < 0.009). Fasting plasma amylin was inversely associated with beta-cell sensitivity to glucose (r = -0.543, P < 0.004).. After successful PKT, type 1 diabetic patients with nondiabetic glycemia exhibit increased fasting and post-glucose load plasma amylin, which appears to be linked to impaired beta-cell function. Thus, higher amylin release in proportion to insulin might also reflect impaired beta-cell function in type 1 diabetic patients after PKT. Topics: Adult; Amyloid; Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Fatty Acids, Nonesterified; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Islet Amyloid Polypeptide; Islets of Langerhans; Kidney Transplantation; Middle Aged; Pancreas Transplantation | 2006 |
Combination of HLA-A24, -DQA1*03, and -DR9 contributes to acute-onset and early complete beta-cell destruction in type 1 diabetes: longitudinal study of residual beta-cell function.
To elucidate the genetic factors contributing to heterogeneity of the rate of beta-cell destruction in type 1 diabetes, we investigated the relationship between the time course of complete beta-cell loss and HLA class I and II alleles. HLA allele frequencies were also examined among subgroups classified by the mode of onset. The subjects were 266 type 1 diabetic patients (among whom 196 patients were studied longitudinally) and 136 normal control subjects. Earlier complete loss of beta-cell function was observed in patients who possessed both HLA-A24 and HLA-DQA1*03 and in patients who had HLA-DR9, compared with those without these HLA alleles (P=0.0057 and 0.0093, respectively). Much earlier complete beta-cell loss was observed in the patients who possessed all of HLA-A24, -DQA1*03, and -DR9 compared with the remaining patients (P=0.0011). The combination of HLA-A24, -DQA1*03, and -DR9 showed a higher frequency in acute-onset than slow-onset type 1 diabetes (P=0.0002). In contrast, HLA-DR2 was associated with a slower rate of progression to complete beta-cell loss. These results indicate that the combination of HLA-A24, -DQA1*03, and -DR9 contributes to the acute-onset and early complete beta-cell destruction, whereas HLA-DR2 has a protective effect against complete beta-cell loss in type 1 diabetes. Topics: Adult; Age of Onset; Alleles; C-Peptide; Diabetes Mellitus, Type 1; Female; Gene Frequency; HLA-A Antigens; HLA-A24 Antigen; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DR Antigens; HLA-DR Serological Subtypes; Humans; Incidence; Insulin-Secreting Cells; Japan; Longitudinal Studies; Male; Middle Aged; Multivariate Analysis; Polymorphism, Restriction Fragment Length | 2006 |
Assessment of glycemic control after islet transplantation using the continuous glucose monitor in insulin-independent versus insulin-requiring type 1 diabetes subjects.
The aim of this study was to assess and compare glycemic control using the continuous glucose monitor (CGMS, Medtronic Minimed, Northridge, CA) in type 1 diabetes mellitus (T1DM) subjects who are insulin-independent versus those who require insulin after islet transplantation alone (ITA).. Glycemic control was assessed using 72-h CGMS in eight T1DM subjects who were insulin-independent after ITA (ITA-II), eight T1DM subjects who were C-peptide-positive but insulin-requiring after ITA (ITA-IR), and eight non-transplanted (NT) T1DM subjects.. Standard deviation of glucose values was not significantly different between ITA-II and ITA-IR subjects (ITA-II, 1.2 +/- 0.1 mM; ITA-IR, 2.0 +/- 0.3 mM; P = 0.072). Both ITA groups were more stable than NT subjects (NT, 3.3 +/- 0.3 mM; P = 0.001 vs. ITA). Mean high glucose values were significantly lower in ITA subjects compared with NT subjects (ITA-II, 10.5 +/- 0.6 mM; ITA-IR, 13.0 +/- 1.0 mM; NT, 16.1 +/- 1.1 mM; P = 0.002). Mean average glucose values were not significantly different among all groups (ITA-I, 6.7 +/- 0.2 mM; ITA-IR, 7.8 +/- 0.3 mM; NT, 7.7 +/- 0.6 mM; P = 0.198). Mean low glucose values were significantly higher in both ITA groups compared with NT subjects (ITA-II, 4.5 +/- 0.2 mM; ITA-IR, 4.3 +/- 0.3 mM; NT, 3.0 +/- 0.2 mM; P = 0.003). Duration of hypoglycemic excursions (<3.0 mM) was markedly reduced in both ITA groups (ITA-II, 0%; ITA-IR, 2.4 +/- 0.2%; NT, 11.8 +/- 4.2%). Glycated hemoglobin was not significantly different between ITA groups (ITA-II, 6.4 +/- 0.2%; ITA-IR, 6.5 +/- 0.3%) and was significantly higher in NT subjects (8.3 +/- 0.2%; P < 0.001 vs. ITA).. CGMS monitoring demonstrates that glycemic lability and hypoglycemia are significantly reduced in C-peptide-positive islet transplant recipients, whether or not supplementary, exogenous insulin is used, compared with non-transplanted T1DM subjects. Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Treatment Outcome | 2006 |
Proinsulin C-peptide elicits disaggregation of insulin resulting in enhanced physiological insulin effects.
Using surface plasmon resonance (SPR) and electrospray mass spectrometry (ESI-MS), proinsulin C-peptide was found to influence insulin-insulin interactions. In SPR with chip-bound insulin, C-peptide mixed with analyte insulin increased the binding, while alone C-peptide did not. A control peptide with the same residues in random sequence had little effect. In ESI-MS, C-peptide lowered the presence of insulin hexamer. The data suggest that C-peptide promotes insulin disaggregation. Insulin/insulin oligomer muM dissociation constants were determined. Compatible with these findings, type 1 diabetic patients receiving insulin and C-peptide developed 66% more stimulation of glucose metabolism than when given insulin alone. A role of C-peptide in promoting insulin disaggregation may be important physiologically during exocytosis of pancreatic beta-cell secretory granulae and pharmacologically at insulin injection sites. It is compatible with the normal co-release of C-peptide and insulin and may contribute to the beneficial effect of C-peptide and insulin replacement in type 1 diabetics. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Protein Binding; Spectrometry, Mass, Electrospray Ionization; Surface Plasmon Resonance | 2006 |
Intrahepatic transplanted islets in humans secrete insulin in a coordinate pulsatile manner directly into the liver.
Intrahepatic islet transplantation is an experimental therapy for type 1 diabetes. In the present studies, we sought to address the following questions: 1) In humans, do intrahepatic transplanted islets reestablish coordinated puslatile insulin secretion? and 2) To what extent is insulin secreted by intrahepatic transplanted islets delivered to the hepatic sinusoids (therefore effectively restoring a portal mode of insulin delivery) versus delivered to the hepatic central vein (therefore effectively providing a systemic form of insulin delivery)? To address the first question, we examined insulin concentration profiles in the overnight fasting state and during a hyperglycemic clamp ( approximately 150 mg/dl) in 10 recipients of islet transplants and 10 control subjects. To address the second question, we measured first-pass hepatic insulin clearance in two recipients of islet autografts after pancreatectomy for pancreatitis versus five control subjects by direct catheterization of the hepatic vein. We report that coordinate pulsatile insulin secretion is reestablished in islet transplant recipients and that glucose-mediated stimulation of insulin secretion is accomplished by amplification of insulin pulse mass. Direct hepatic catheterization studies revealed that intrahepatic islets in humans do deliver insulin directly to the hepatic sinusoid because approximately 80% of the insulin is extracted during first pass. In conclusion, intrahepatic islet transplantation effectively restores the liver to pulsatile insulin delivery. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucose; Glucose Clamp Technique; Hepatic Veins; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Male; Middle Aged; Pancreatectomy; Pancreatitis; Periodicity | 2006 |
Evaluation of islet transplantation from non-heart beating donors.
We evaluated islet transplantation from non-heart beating donors (NHBDs) with our Kyoto Islet Isolation Method. All patients had positive C-peptide after transplantation. The average HbA(1C) levels of the five recipients significantly improved from 7.8 +/- 0.4% at transplant to 5.2 +/- 0.2% currently (p < 0.01). Three patients with no or a single autoantibody became insulin independent while the other two patients with double autoantibodies reduced their insulin requirement but did not become insulin independent. C-peptide in patients who became insulin-independent gradually increased after each transplantation whereas C-peptide in patients who did not become insulin-independent from 3 months after the first transplantation to the next transplantation dramatically decreased. The beta-score of the three patients who became insulin independent was the best of eight. In conclusion, our method makes it feasible to use NHBDs for islet transplant into type 1 diabetic patients efficiently. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Islets of Langerhans Transplantation; Length of Stay; Male; Postoperative Period; Retrospective Studies; Tissue Donors; Treatment Outcome | 2006 |
Metabolic factors affecting residual beta cell function assessed by C-peptide secretion in patients with newly diagnosed type 1 diabetes.
In recent onset of type 1 diabetes, the residual beta cell function, assessed by baseline and/or stimulated C-peptide secretion, can be a useful parameter to establish the extension of beta cell destruction. How metabolic parameters at diagnosis influence residual C-peptide secretion is not well established.. We analyzed 553 consecutive patients with recent onset (<4 weeks) of type 1 diabetes (250 females and 303 males, mean age 15+/-8 years). Baseline and stimulated C-peptide by i.v. glucagon were evaluated using a highly sensitive radio-immunoassay. Metabolic parameters including blood glucose, HbA1c, insulin dose, and BMI were also evaluated.. Baseline and stimulated C-peptide were 0.26+/-0.22 and 0.47+/-0.38 nmol/l and correlated positively with age (p<0.001). There was no significant correlation between C-peptide and blood glucose at diagnosis. BMI was positively correlated with both baseline and stimulated C-peptide secretion (p<0.001). By contrast, HbA1c levels inversely correlated with both baseline and stimulated C-peptide secretion (p<0.001).. In type 1 diabetes at diagnosis, baseline and stimulated C-peptide are higher in pubertal and young adult patients compared with pre-pubertal patients suggesting that such parameter can be used as an end point marker for studies aimed at protecting and/or restoring beta cells in patients with substantial beta cell function. High levels of HbA1c and lower BMI are dependent variables of C-peptide values. Topics: Adolescent; Adult; Biomarkers; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Early Diagnosis; Female; Glucagon; Glycated Hemoglobin; Hormones; Humans; Hypoglycemic Agents; Insulin; Insulin-Secreting Cells; Male; Multivariate Analysis; Prognosis; Radioimmunoassay | 2006 |
Elevated circulating adiponectin in type 1 diabetes is associated with long diabetes duration.
To study circulating adiponectin concentrations in relation to diabetes duration and endogenous insulin secretion in patients with type 1 diabetes.. Patients with haemoglobin A1c (HbA1c) < 6% (reference range 3.6-5.4%) were selected for the study. Twenty-two men and 24 women [age 41.3 +/- 13.8 years (mean +/- SD), diabetes duration 4 months to 52 years] participated. Healthy controls (15 women and nine men, age 41.3 +/- 13.0 years) were also included. Overnight fasting serum samples were analysed for adiponectin, HbA1c, C-peptide and lipoproteins.. Significant positive associations were found between adiponectin concentrations and diabetes duration in univariate and multiple regression analyses. Serum adiponectin averaged 9.7 +/- 5.3 [median 8.1, interquartile range (IQR) 3.6] mg/l in patients with diabetes duration less than 10 years and 17.8 +/- 10.7 (median 14.7, IQR 7.5) mg/l in patients with longer duration (P = 0.0001). Among the patients, 24 were without detectable (< 100 pmol/l) and 22 with detectable C-peptide levels (185 +/- 91 pmol/l). C-peptide levels in controls averaged 492 +/- 177 pmol/l. HbA1c was 5.7 +/- 0.6% in patients without detectable C-peptide and 5.6 +/- 0.4% in patients with detectable C-peptide (ns). Serum adiponectin was higher in patients without detectable C-peptide than in patients with detectable C-peptide [17.3 +/- 11.1 vs. 10.6 +/- 5.8 mg/l (P < 0.005)] and in the controls [10.1 +/- 2.9 mg/l (P < 0.001 vs. patients without detectable C-peptide)].. The increase in circulating adiponectin concentrations in patients with type 1 diabetes appears to be strongly associated with long diabetes duration, irrespective of the metabolic control. Among other factors, a putative role for residual beta-cell function in the regulation of circulating adiponectin levels can be considered but we did not find sufficient evidence for this in the present study. Topics: Adiponectin; Adult; Analysis of Variance; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Middle Aged; Regression Analysis; Statistics, Nonparametric; Time Factors | 2006 |
C-Peptide reverses nociceptive neuropathy in type 1 diabetes.
We examined the therapeutic effects of C-peptide on established nociceptive neuropathy in type 1 diabetic BB/Wor rats. Nociceptive nerve function, unmyelinated sural nerve fiber and dorsal root ganglion (DRG) cell morphometry, nociceptive peptide content, and the expression of neurotrophic factors and their receptors were investigated. C-peptide was administered either as a continuous subcutaneous replacement dose via osmopumps or a replacement dose given once daily by subcutaneous injection. Diabetic rats were treated from 4 to 7 months of diabetes and were compared with control and untreated diabetic rats of 4- and 7-month duration. Osmopump delivery but not subcutaneous injection improved hyperalgesia and restored the diabetes-induced reduction of unmyelinated fiber number (P < 0.01) and mean axonal size (P < 0.05) in the sural nerve. High-affinity nerve growth factor (NGF) receptor (NGFR-TrkA) expression in DRGs was significantly reduced at 4 months (P < 0.01). Insulin receptor and IGF-I receptor (IGF-IR) expressions in DRGs and NGF content in sciatic nerve were significantly decreased in 7-month diabetic rats (P < 0.01, 0.05, and 0.005, respectively). Osmopump delivery prevented the decline of NGFR-TrkA, insulin receptor (P < 0.05), and IGF-IR (P < 0.005) expressions in DRGs and improved NGF content (P < 0.05) in sciatic nerve. However, subcutaneous injection had only marginal effects on morphometric and molecular changes in diabetic rats. We conclude that C-peptide exerts beneficial therapeutic effects on diabetic nociceptive neuropathy and that optimal effects require maintenance of physiological C-peptide concentrations for a major proportion of the day. Topics: Animals; C-Peptide; Calcitonin; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Ganglia, Spinal; Male; Nerve Fibers; Nerve Regeneration; Neuritis; Neurons; Rats; Rats, Inbred BB; Reference Values; Substance P | 2006 |
Living donor islet transplantation, the alternative approach to overcome the obstacles limiting transplant.
We performed the world's first successful living donor islet transplantation for unstable diabetes. A total of 408,114 islet equivalents were isolated from half a living pancreas and transplanted immediately to the recipient who was a 27-year-old female. The donor was a 56-year-old female in good health, mother of the recipient. The islets functioned immediately, and the recipient was weaned completely from insulin on the 22nd posttransplant day, and has maintained excellent glycemic control since. The donor was discharged on the 18th postoperative day with normal oral glucose tolerance test and without complications. Living donor islet transplantation could cure one insulin-dependent diabetes mellitus patients with a single donor. There are some advantages in the living donor islet transplantation: (a) living donor can alleviate the issue of donor shortage; (b) highly potent islets can be isolated from a living donor; and (c) the recipient can be treated with immunosuppressant and controlled blood glucose level tightly prior to the transplantation. These are important factors in overcoming the obstacles limiting islet transplantation. We believe that the living donor islet transplantation may become an additional option in treating insulin-dependent diabetes. Topics: Adult; Antibodies, Monoclonal; Basiliximab; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Infliximab; Insulin; Islets of Langerhans Transplantation; Living Donors; Middle Aged; Postoperative Period; Preoperative Care; Recombinant Fusion Proteins; Sirolimus; Tacrolimus; Time Factors; Treatment Outcome | 2006 |
[Selected immunologic and biochemical risk factors of the retinopathy and nephropathy development in children with diabetes mellitus type 1].
Despite that numerous investigations on the nature of diabetic microangiopathy were carried out, its pathomechanism remains unclear.. The aim of the study was to analyze the relation between early diabetic microangiopathy and the proinflammatory cytokines, NAG and its A and B isoforms in blood and urine in children diagnosed with diabetes mellitus type 1.. The study was carried out on the group of 56 children with diabetes mellitus 1 (age 13.6+/-3.74) and 35 healthy children selected as the controls. All the patients had 24 hrs albuminuria, HbA1c, C-peptide as well as the NAG enzyme and its A and B isoforms serum and urine activities measured. Additionally, all the children had TNF-a and IL6 level in serum measured. Each patient had 24 hrs blood pressure monitored and underwent ophthalmologic examination.. Children with long-standing diabetes mellitus and retinopathy (group 1, n=15) were older and were characterized by a statistically significant longer duration of the disease and higher HbA1c level in comparison with the patients who presented with no sign of diabetic retinopathy (group 2, n=41). In the group 1 statistically significant higher TNF-alpha serum level (p=0.01), NAG (p=0.002) and its isoforms A (p=0.007) and B (p=0.001) urine activities were measured in relation to the group 2. Additionally the level of IL-6 and NAG and its isoforms A and B serum activities were higher in group 1 than in group 2, however the differences were of no statistical significance. Moreover the children from group 2 in comparison with the healthy controls showed statistically significant higher TNF-alpha serum activity (p=0.016) and NAG (p<0.001) and its A (p<0.001) and B (p<0.001) isoforms both serum and urine activities.. The occurrence of the detectable serum TNF-alpha activity in children with diabetes mellitus type 1 showing no sign of diabetic retinopathy and nephropathy and no microalbuminuria with the concomitant increase of NAG and its isoforms serum and urine activities might point toward prompt occurrence of these changes in the eye and the kidneys. Topics: Adolescent; Albuminuria; Biomarkers; C-Peptide; Child; Comorbidity; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Human Development; Humans; Hypertension; Interleukin-6; Male; Protein C; Risk Factors; Tumor Necrosis Factor-alpha | 2006 |
Technique, complications, and therapeutic efficacy of percutaneous transplantation of human pancreatic islet cells in type 1 diabetes: the role of US.
To retrospectively evaluate the role of ultrasonography (US) with regard to the technique, complications, and therapeutic efficacy of percutaneous intrahepatic transplantation of human pancreatic islet cells with combined US and fluoroscopic guidance.. The institutional review board approved the study, and informed consent was obtained from all patients. After kidney transplantation, 34 uremic diabetic patients (20 men, 14 women; mean age, 40.9 years; age range, 29-61 years) underwent percutaneous intrahepatic transplantation of islet cells. Portal vein patency and liver echotexture were preliminarily assessed with color Doppler US. US also was used to identify early complications and presence (group A patients) or absence (group B patients) of hepatic parenchymal changes. Differences between the two groups in C peptide serum level and range were analyzed (Mann-Whitney test). Therapeutic efficacy of transplantation was assessed with regard to insulin independence period (rate and duration), exogenous insulin requirement, glycated hemoglobin, and C peptide level. A C peptide level of more than 0.5 ng/mL was considered to indicate well-functioning islet cells.. Fifty-eight procedures were technically successful, with a single puncture used in 51 of 58 patients. Complications occurred in three of 58 patients (hemoperitoneum, hemothorax, and thrombosis in one patient each) and were conservatively treated and resolved. Duration of insulin independence in 12 patients was more than 3 months (mean, 21 months). Well-functioning islet cells at 6 years were found in 19 of 34 patients. Hyperechoic parenchymal changes were evident at US in 12 of 34. No statistically significant difference in C peptide level was found between groups (P > .05), but a wider range of values was recorded in group B.. Complication rate of transplantation with US and fluoroscopic guidance was low. Well-functioning islet cells were found in about 50% of patients at 6 years of follow-up. Hepatic implantation of islet cells was evident on US images in more than one-third of patients. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Fluoroscopy; Hemoglobins, Abnormal; Humans; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Liver; Male; Middle Aged; Postoperative Complications; Retrospective Studies; Treatment Outcome; Ultrasonography, Doppler, Color | 2005 |
{beta}-Cell function following human islet transplantation for type 1 diabetes.
Islet transplantation can provide metabolic stability for patients with type 1 diabetes; however, more than one donor pancreas is usually required to achieve insulin independence. To evaluate possible mechanistic defects underlying impaired graft function, we studied five subjects at 3 months and four subjects at 12 months following intraportal islet transplantation who had received comparable islet equivalents per kilogram (12,601 +/- 1,732 vs. 14,384 +/- 2,379, respectively). C-peptide responses, as measures of beta-cell function, were significantly impaired in both transplant groups when compared with healthy control subjects (P < 0.05) after intravenous glucose (0.3 g/kg), an orally consumed meal (600 kcal), and intravenous arginine (5 g), with the greatest impairment to intravenous glucose and a greater impairment seen in the 12-month compared with the 3-month transplant group. A glucose-potentiated arginine test, performed only in insulin-independent transplant subjects (n = 5), demonstrated significant impairments in the glucose-potentiation slope (P < 0.05) and the maximal response to arginine (AR(max); P < 0.05), a measure of beta-cell secretory capacity. Because AR(max) provides an estimate of the functional beta-cell mass, these results suggest that a low engrafted beta-cell mass may account for the functional defects observed after islet transplantation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Energy Intake; Female; Glucose Tolerance Test; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Reference Values | 2005 |
Rescue purification maximizes the use of human islet preparations for transplantation.
The relative inefficiency of the islet purification process may hamper obtaining enough islets for transplantation even with adequate pre-purification counts. In this study, we determined the effect of an additional purification step on total islet yields and pancreas utilization at our center. Twenty-five pancreata were processed using the automated method followed by continuous gradient purification (CGP), and the less pure islet fractions were subjected to additional rescue gradient purification (RGP). CGP and RGP islets were combined and transplanted into patients with type 1 diabetes. CGP and RGP islets showed no significant differences in cell viability, insulin secretion in vitro and function when transplanted into chemically diabetic mice. Mean RGP contribution to the final preparation was 27.9 +/- 19.9%. In 12 of 25 preparations, CGP yielded <5000 IEQ/kg of recipient body weight, and inclusion of RGP islets to the final preparation allowed to obtain the minimal islet number required for transplantation. Transplanted islets resulted in sustained C-peptide production, HbA1(C) normalization and insulin-independence or reduced insulin requirements. Taken together, our data suggest that RGP islets are comparable in terms of viability and potency to CGP islets. RGP may be of assistance in maximizing the number of islet preparations successfully used in transplant protocols. Topics: Animals; C-Peptide; Cell Separation; Cell Survival; Centrifugation, Density Gradient; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Fluoresceins; Glucose Tolerance Test; Glycated Hemoglobin; Graft Survival; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Mice; Mice, Nude; Pancreas; Perfusion; Propidium; Time Factors; Tissue and Organ Procurement; Tissue Donors; Tissue Preservation | 2005 |
Beta-score: an assessment of beta-cell function after islet transplantation.
Success after islet transplantation can be defined in terms of insulin independence, C-peptide secretion, or glycemic control. These measures are interdependent and all need to be considered in evaluating beta-cell function after islet transplantation. For the current study, a composite beta-score was developed that provides an integrated measure of beta-cell function success after islet transplantation.. The proposed scoring system gave 2 points each for normal fasting glucose, HbA(1c), stimulated C-peptide, and absence of insulin or oral hypoglycemic agent use. No points were awarded if the fasting glucose was in the diabetic range, the HbA(1c) was >6.9%, C-peptide secretion was absent on stimulation, or daily insulin use was in excess of 0.24 units/kg. One point was given for intermediate values. The score ranged from 0 to 8 and was correlated with the glucose value 90 min after a standard mixed meal challenge (n = 218) in 57 subjects before and after islet transplantation. The score was also used to follow subjects for up to 5 years after islet transplantation.. The beta-score correlated well with the plasma glucose level 90 min after a mixed meal challenge (r = -0.849, P < 0.001). On follow-up, the beta-score rose after the first transplant and was maintained up to 5 years, demonstrating continuing function of the transplanted beta-cells.. The beta-score provides a simple clinical scoring system that encompasses glycemic control, diabetes therapy, and endogenous insulin secretion that correlates well with physiological measures of beta-cell function. On this basis, it is suitable as an overall measure of beta-cell transplant function. The beta-score gives an integrated measure of beta-cell function as a continuum that may be more useful than simply assessing the presence or absence of insulin independence. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Graft Survival; Humans; Hypoglycemic Agents; Islets of Langerhans; Islets of Langerhans Transplantation; Postprandial Period; Severity of Illness Index | 2005 |
Hepatitis C virus infection-related Type 1 diabetes mellitus.
Hepatitis C virus (HCV) has been associated with Type 2 diabetes mellitus, and many other viral infections have been associated with Type 1 diabetes mellitus (Type 1 DM). An association between HCV and Type 1 DM, however, has never been reported. We report the case of a 66-year-old man who developed Type 1 DM 1 year after a blood transfusion-related HCV infection. Testing of serum specimens obtained in the weeks following blood transfusion demonstrated evidence of both acute HCV infection and development of Type 1 DM-related autoantibodies.. A 66-year-old Taiwanese male received blood transfusions during coronary artery bypass surgery in 1987. Serum specimens, obtained as part of a study on post-transfusion hepatitis, demonstrated that the patient had no evidence of hepatitis C prior to transfusion, but developed acute HCV infection after transfusion. One year later, the patient, who had no personal or family history of diabetes, presented with diabetic ketoacidosis, and tests for C-peptide confirmed that he had Type 1 DM. Testing of pre- and post-operative serum specimens demonstrated that the patient developed positive tests for islet cell and glutamic acid decarboxylase antibodies 4 weeks after transfusion, concurrent with the development of acute HCV infection.. The simultaneous development of HCV infection and diabetes-related autoantibodies suggest a relationship between HCV and Type 1 DM. Topics: Acute Disease; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Hepacivirus; Hepatitis C; Humans; Islets of Langerhans; Male; Taiwan; Transfusion Reaction | 2005 |
Coronary artery disease is common in nonuremic, asymptomatic type 1 diabetic islet transplant candidates.
Coronary artery disease (CAD) is the most common cause of death in patients with type 1 diabetes. Asymptomatic CAD is common in uremic diabetic patients, but its prevalence in nonuremic type 1 diabetic patients is unknown. The prevalence of CAD was determined by coronary angiography and the performance of noninvasive cardiac investigation evaluated in type 1 diabetic islet transplant (ITX) candidates with preserved renal function.. A total of 60 consecutive type 1 diabetic ITX candidates (average age 46 years [mean 24-64], 23 men, and 47% ever smokers) underwent coronary angiography, electrocardiographic stress testing (EST), and myocardial perfusion imaging (MPI) in a prospective cohort study. CAD was indicated on angiography by the presence of stenoses >50%. Models to predict CAD were examined by logistic regression.. Most subjects (53 of 60) had no history or symptoms of CAD; 23 (43%) of these asymptomatic subjects had stenoses >50%. CAD was associated with age, duration of diabetes, hypertension, and smoking. Although specific, EST and MPI were not sensitive as predictors of CAD on angiography (specificity 0.97 and 0.93, sensitivity 0.17 and 0.04, respectively) but helped identify two of three subjects requiring revascularization. EST and MPI did not enhance logistic regression models. A clinical algorithm to identify low-risk subjects who may not require angiography was highly sensitive but was applicable only to a minority (n = 8, sensitivity 1.0, specificity 0.27, negative predictive value 1.0).. Nonuremic type 1 diabetic patients with hypoglycemic unawareness and/or metabolic lability referred for ITX are at high risk for asymptomatic CAD despite negative noninvasive investigations. Aggressive management of cardiovascular risk factors and further investigation into optimal cardiac risk stratification in type 1 diabetes are warranted. Topics: Adult; Aged; Awareness; Blood Pressure; C-Peptide; Coronary Angiography; Coronary Disease; Coronary Stenosis; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Female; Humans; Hypoglycemia; Islets of Langerhans Transplantation; Male; Middle Aged; Postoperative Complications; Predictive Value of Tests; Risk Factors; Sensitivity and Specificity; Smoking | 2005 |
Diabetes in the young: not always as it seems.
Topics: Adult; Asian People; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Male | 2005 |
Simultaneous pancreas-kidney transplants in type I and type II diabetic patients with end-stage renal disease: similar 10-year outcomes.
Herein we report 10- to 15-year results of simultaneous pancreas-kidney (SPK) transplants in 135 type I and type II insulin-dependent diabetes mellitus (IDDM) patients.. Diabetes type was defined by the absence (type I) or presence (type II) of C-peptide. The freedom from dialysis and need for insulin defined graft survival. Patient survival was verified by record review and the Social Security Death Registry. The mean follow-up exceeded 100 months.. Type II IDDM present in 28% of the 135 cohort, predominately among African-Americans (AA). The type II group was two-thirds AA (43% of the total AA patients) and 17% of the non-African-American (nAA) group. The difference between the two groups by C-peptide level was significant (P = .001). Type II patients had a higher body mass index, were slightly older at the onset of DM, but had similar duration of IDDM before ESRD. At 5 and 10 years, pancreas survival for type 1 DM was 71% and 49%; for type II DM it was 67% and 56% (P = .52). Kidney survival for type I DM was 77% and 50%; for type II it was 72% and 56% (P = .65). Patient survival for type I DM was 85% and 63%; for type II DM it was 73% and 70% (P = .98).. We conclude that the outcomes of SPK transplants are equivalent regardless of diabetes type. Accordingly, the decision whether to perform pancreas transplants in diabetic recipients of kidney allografts should be based on general acceptance criteria not diabetes type. Topics: Adult; Black People; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; District of Columbia; Follow-Up Studies; Graft Survival; Humans; Kidney Failure, Chronic; Kidney Transplantation; Pancreas Transplantation; Retrospective Studies; Survival Analysis; Time Factors; Treatment Outcome | 2005 |
The effect of C-peptide on cognitive dysfunction and hippocampal apoptosis in type 1 diabetic rats.
Primary diabetic encephalopathy is a recently recognized late complication of diabetes resulting in a progressive decline in cognitive faculties. In the spontaneously type 1 diabetic BB/Wor rat, we recently demonstrated that cognitive impairment was associated with hippocampal apoptotic neuronal loss. Here, we demonstrate that replacement of proinsulin C-peptide in this insulinopenic model significantly prevented spatial learning and memory deficits and hippocampal neuronal loss. C-peptide replacement prevented oxidative stress-, endoplasmic reticulum-, nerve growth factor receptor p75-, and poly(ADP-ribose) polymerase-related apoptotic activities. It partially ameliorated apoptotic stresses mediated via impaired insulin and IGF activities. These findings were associated with the prevention of increased expression of Bax and active caspase 3 and the frequency of caspase 3-positive neurons. The results show that several partially interrelated apoptotic mechanisms are involved in primary encephalopathy and suggest that impaired insulinomimetic action by C-peptide plays a prominent role in cognitive dysfunction and hippocampal apoptosis in type 1 diabetes. Although these abnormalities were not fully prevented by C-peptide replacement, the findings suggest that this regime will substantially prevent cognitive decline in the type 1 diabetic population. Topics: Animals; Apoptosis; C-Peptide; Caspase 12; Caspases; Cognition; Cognition Disorders; Diabetes Mellitus, Type 1; Disease Models, Animal; Hippocampus; Male; Maze Learning; Polymerase Chain Reaction; Prediabetic State; Rats; Rats, Inbred BB | 2005 |
Pancreas islet transplantation in patients with type 1 diabetes mellitus after kidney transplantation.
Diabetic patients with end-stage renal disease have a high mortality rate. A combined kidney-pancreas transplant is associated with greater life expectancy. Pancreas islet transplantation is an alternative involving a lower degree of morbidity. We present two patients, of 41 and 37 years of age, with a long history of diabetes mellitus (C-peptide negative), both with a previous kidney transplant, who had been treated with 22 and 28 U of insulin/d, respectively. Both patients had frequent episodes of unawareness hypoglycemia. Pancreatic islets were infused to a total of 7809 and 19,180 IE/kg, respectively. Basal posttransplant C peptide levels were 2.9 and 1.3 ng/mL. After the implant, one patient required occasional doses of insulin, and the other patient more than 50% reduced dose. After the first implant neither patient had any episodes of unawareness hypoglycemia. HbA1c at 4 months were 6.2% and 6.9%. There were no transplant-related complications. Topics: Adult; Awareness; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drug Therapy, Combination; Female; Humans; Hypoglycemia; Hypoglycemic Agents; Immunosuppressive Agents; Insulin; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Postoperative Complications; Postoperative Period | 2005 |
Kidney-pancreas transplants: is it so difficult to start a program?
For selected patients with type 1 diabetes mellitus and end-stage renal failure, simultaneous kidney-pancreas (SKP) or pancreas after kidney (PAK) transplantation is the treatment of choice. However, it is frequently difficult to start a program for fear of serious intraabdominal complications in an immunosuppressed patient. We review our initial experience with these transplantations.. Twenty-three patients (20 SKP, 3 PAK) with type 1 diabetes mellitus received transplants between June 2000 and October 2003. All received immunosuppression therapy with thymoglobulin, prednisone, tacrolimus, and mycophenolate mofetil. The operation included portal venous drainage and exocrine enteric drainage. Rejections were biopsy-proved. Cytomegalovirus prophylaxis with gancyclovir was administered.. The mean follow-up is 13 months (range, 1-30 months) for recipients of mean age 39 +/- 7 years (17 men, 6 women). Mean cold ischemia time for kidney was 10.2 +/- 3.9 hours, and for pancreas was 10.5 +/- 3 hours. The rate of initial graft function was 100%. Graft rejection rate was 8%. The repeat laparotomy rate was 53% (12 patients), with a mean of 0.8 procedures per patient (range, 0 to 5). At the end of follow-up, patient survival was 95%, kidney survival was 85%, and pancreas survival was 83%. Patients with a functioning graft were insulin-free, with a mean fasting glucose concentration of 79 +/- 7 mg/dL, hemoglobin A1C of 4.5% (range, 4% to 4.9%) C-peptide of 5.9 ng/mL (range, 2.1 to 12 ng/mL), and a mean serum creatinine level of 1.6 mg/dL (range, 0.9 to 4.6 mg/dL). There was 1 death, due to posttransplantation lymphoproliferative disease confined to the pancreatic graft and abdominal sepsis at 3 months posttransplantation.. Our results are similar to those of other series of SPK or PAK transplantations: low acute rejection rates, frequent requirement for repeat laparotomy, and good patient and graft survival, permitting an excellent quality of life. Topics: Adult; C-Peptide; Cytomegalovirus Infections; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Graft Rejection; Graft Survival; Hematoma; Humans; Immunosuppression Therapy; Kidney Failure, Chronic; Kidney Transplantation; Male; Pancreas Transplantation; Postoperative Complications; Reoperation; Time Factors | 2005 |
Association between a protein polymorphism in the start codon of the vitamin D receptor gene and severe diabetic retinopathy in C-peptide-negative type 1 diabetes.
The vitamin D (VD) receptor (VDR) is extensively expressed in retina. The plasma concentration of 1,25-dihydroxyvitamin D3 has been inversely correlated with the severity of diabetic retinopathy (DR), which raises the possibility that VD, through its antiinflammatory, antioxidant, antiproliferative, and antiangiogenic properties, may protect diabetic retina. The TaqI VDR polymorphism has been associated with severe DR. The FokI VDR polymorphism is a T-to-C substitution in the first codon (f allele), abolishing the first translation initiation site and resulting in a peptide lacking three amino acids (F allele), which increases the transcriptional activity of VDR.. To examine whether FokI polymorphism is involved in severe DR, 254 Caucasians with longstanding C-peptide-negative type 1 diabetes, 128 patients with absent/mild DR (control group), and 126 patients with preproliferative/proliferative DR (study group) were genotyped using PCR-restriction fragment length polymorphism analysis.. The genotype distribution was in Hardy-Weinberg equilibrium and was different between groups (P = 0.046). The frequency of F allele was significantly higher in the control (66.4%) than in the study group (56%, odds ratio = 0.64, 95% confidence interval 0.44-0.92, P = 0.016). In subjects with fewer than 25 yr of diabetes duration (median value, n = 134), this association was strongly increased (P = 0.0008).. In conclusion, we observed, in a cohort of Caucasians with C-peptide-negative type 1 diabetes, a novel association between the functional FokI VDR polymorphism and severe DR, especially among subjects with fewer than 25 yr of diabetes duration. Topics: Adult; C-Peptide; Case-Control Studies; Codon, Initiator; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Polymorphism, Genetic; Receptors, Calcitriol; Risk Factors; Severity of Illness Index; White People | 2005 |
Natural history of kidney graft survival, hypertrophy, and vascular function in end-stage renal disease type 1 diabetic kidney-transplanted patients: beneficial impact of pancreas and successful islet cotransplantation.
Diabetes, hypertension, infections, and nephrotoxicity of certain immunosuppressive drugs (i.e., calcineurin inhibitors) can reduce functional survival of the kidney graft. Our aim was to evaluate survival, hypertrophy, and vascular function of the kidney graft in end-stage renal disease (ESRD) type 1 diabetic patients after transplant.. The study population consisted of 234 ESRD type 1 diabetic patients who underwent kidney-pancreas (KP; 166 patients), successful kidney-islet (KI-s; 24 patients), and kidney (KD; 44 patients) transplant. Kidney size, graft survival, vascular function, and microalbuminuria were evaluated prospectively yearly for 6 years. Sixty-eight protocol kidney biopsies were performed routinely between 1993 and 1998 cross-sectionally (3.2 +/- 0.3 years from kidney transplant).. The KP and KI-s groups had better cumulative kidney graft survival at 6 years than did the KD group (KP: 73%; KI-s: 86%; KD: 42%, P < 0.01). The KP group but not the KI-s/KD groups showed a persistent kidney graft hypertrophy up to 6 years of follow-up. A significant increase in creatinine levels from baseline to year 6 was evident in the KD group (1.58 +/- 0.08 to 2.78 +/- 0.44 mg/dl, P < 0.05) but not in the KP/KI-s groups. The KP/KI-s groups only showed a reduction of renal resistance index from baseline to year 6 (KP at baseline: 0.74 +/- 0.01 to 0.68 +/- 0.01%, P < 0.01; KI-s at baseline: 0.72 +/- 0.02 to 0.69 +/- 0.02%, P < 0.05). At year 6, an increase from baseline in urinary albumin excretion was observed only in the KD group (31.4 +/- 9.0 to 82.9 +/- 33.6 mg/l, P < 0.05). Preliminary data suggested that graft nitric oxide (NO) expression was higher in the KP/KI-s groups than in the KD group (data not shown).. In ESRD type 1 diabetic patients, KP and KI-s compared with KD resulted in enhanced kidney graft survival, hypertrophy, and vascular function. Topics: Adult; Biopsy; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glycated Hemoglobin; Graft Survival; Humans; Hypertrophy; Immunosuppression Therapy; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Survival Analysis; Time Factors; Treatment Outcome | 2005 |
The effect of pancreatic islet transplantation on progression of diabetic retinopathy and neuropathy.
Pancreatic islet transplantation (PIT) has only become an effective treatment for type 1 diabetes mellitus within the past 4 years. As a result, the long-term effects of PIT on progression of diabetic neuropathy and retinopathy are unknown. The benefit of halting or improving diabetic neuropathy and retinopathy is of particular interest since most PIT recipients have not developed the advanced complications of diabetes. Herein, we describe the improvement and stabilization of diabetic neuropathy and retinopathy in 12 PIT recipients.. Between January 1, 2002, and June 30, 2004, there have been 12 patients who have received PIT. Currently, there are eight patients who have sufficient follow-up to assess the progression of diabetic retinopathy and neuropathy. To assess for disease progression, patients were examined by a single ophthalmologist and single neurologist throughout the study period. Eye exams were performed using a slit-lamp exam while neurological status was assessed using electromyelograms and clinical exams.. All PIT recipients had decreases in hemoglobin A(1)C and increases in serum C-peptide. All study patients had stabilization of their retinopathic disease. One patient demonstrated improvement of retinopathy at 1 year posttransplant. Fifty percent of patients demonstrated improvement or stabilization of their diabetic neuropathy. One patient had mild reinnervation of the fingers and wrist extensors by clinical exam 1 year posttransplant. Four patients exhibited an average decrease of 19% in sural nerve conduction velocities.. Our series has demonstrated that all PIT recipients have had stabilization of their diabetic retinopathy and that 50% of patients exhibited stabilization or even improvement of their diabetic neuropathy. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Diabetic Retinopathy; Female; Humans; Islets of Langerhans Transplantation; Male; Middle Aged; Neurologic Examination | 2005 |
Five-year follow-up after clinical islet transplantation.
Islet transplantation can restore endogenous beta-cell function to subjects with type 1 diabetes. Sixty-five patients received an islet transplant in Edmonton as of 1 November 2004. Their mean age was 42.9 +/- 1.2 years, their mean duration of diabetes was 27.1 +/- 1.3 years, and 57% were women. The main indication was problematic hypoglycemia. Forty-four patients completed the islet transplant as defined by insulin independence, and three further patients received >16,000 islet equivalents (IE)/kg but remained on insulin and are deemed complete. Those who became insulin independent received a total of 799,912 +/- 30,220 IE (11,910 +/- 469 IE/kg). Five subjects became insulin independent after one transplant. Fifty-two patients had two transplants, and 11 subjects had three transplants. In the completed patients, 5-year follow-up reveals that the majority ( approximately 80%) have C-peptide present post-islet transplant, but only a minority ( approximately 10%) maintain insulin independence. The median duration of insulin independence was 15 months (interquartile range 6.2-25.5). The HbA(1c) (A1C) level was well controlled in those off insulin (6.4% [6.1-6.7]) and in those back on insulin but C-peptide positive (6.7% [5.9-7.5]) and higher in those who lost all graft function (9.0% [6.7-9.3]) (P < 0.05). Those who resumed insulin therapy did not appear more insulin resistant compared with those off insulin and required half their pretransplant daily dose of insulin but had a lower increment of C-peptide to a standard meal challenge (0.44 +/- 0.06 vs. 0.76 +/- 0.06 nmol/l, P < 0.001). The Hypoglycemic score and lability index both improved significantly posttransplant. In the 128 procedures performed, bleeding occurred in 15 and branch portal vein thrombosis in 5 subjects. Complications of immunosuppressive therapy included mouth ulcers, diarrhea, anemia, and ovarian cysts. Of the 47 completed patients, 4 required retinal laser photocoagulation or vitrectomy and 5 patients with microalbuminuria developed macroproteinuria. The need for multiple antihypertensive medications increased from 6% pretransplant to 42% posttransplant, while the use of statin therapy increased from 23 to 83% posttransplant. There was no change in the neurothesiometer scores pre- versus posttransplant. In conclusion, islet transplantation can relieve glucose instability and problems with hypoglycemia. C-peptide secretion was maintained in the majority of subjects for up to 5 years, al Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Hypoglycemia; Insulin; Islets of Langerhans Transplantation; Male; Postoperative Complications; Survival Analysis; Time Factors; Treatment Outcome | 2005 |
Comparison of clinical and laboratory characteristics between adult-onset type 1 diabetes and latent autoimmune diabetes in adults.
Topics: Adult; Age of Onset; Biomarkers; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypertension; Male | 2005 |
Alloreactivity against repeated HLA mismatches of sequential islet grafts transplanted in non-uremic type 1 diabetes patients.
Islet transplantation can restore insulin production in type 1 diabetes patients. However, survival of the islet allografts will face rejection or recurrence of autoimmunity or a combination of both. In a study on islet-after-kidney transplants, we previously reported that islet cell recipients presented low T-cell alloresponses for HLA mismatches that were shared by the islet cell graft and the prior kidney graft, that is, repeated mismatch, while vigorous responses were measured against novel HLA mismatches.. We now investigated T-cell alloreactivity to repeated HLA-mismatches in three non-uremic type 1 diabetic patients each receiving three sequential islet cell implants.. These islet-after-islet recipients patients exhibited low or absent responses to repeated mismatches to the first graft which was accompanied by sustained graft function, and reduced responsiveness towards subsequent grafts. In one patient, T-cell responses towards these mismatches were noticed following new mismatches in subsequent grafts, with loss of graft function.. These case reports further support the view that subsequent islet implantations can reduce alloreactivity for repeated HLA mismatches. They demonstrate the usefulness of monitoring T-cell reactivity against islet allografts to correlate immune function with graft survival and to identify conditions for preservation of beta-cell function. Topics: Antilymphocyte Serum; Autoimmunity; C-Peptide; Diabetes Mellitus, Type 1; Graft Survival; Histocompatibility Testing; Humans; Immunosuppressive Agents; Islets of Langerhans Transplantation; Isoantibodies; Postoperative Period; T-Lymphocytes; T-Lymphocytes, Cytotoxic; Transplantation Conditioning; Transplantation, Homologous; Uremia | 2005 |
Proinsulin C-peptide activates vagus efferent output in rats.
The aim of this study was to examine the effect of proinsulin C-peptide on the autonomic nervous systems in rats. Intravenous administration of C-peptide gradually increased electrophysiological activity of the vagus nerves into the stomach and pancreas for at least 90 min. It also slightly increased gastric acid secretion that was suppressed by the treatment with atropine. Intraperitoneal injection of C-peptide did not affect the basal and stress-induced norepinephrine (NE) turnover rate, a biochemical index of sympathetic nerve activity. These results indicate that C-peptide increases parasympathetic nerve activity without affecting sympathetic nerve activity. This could explain, at least in part, the ameliorating effects of C-peptide on impaired cardiac autonomic nerve functions in patients with type 1 diabetes. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Female; Gastric Acid; Gastric Mucosa; Heart; Humans; Injections, Intravenous; Myocardium; Rats; Rats, Wistar; Stomach; Sympathetic Nervous System; Vagus Nerve | 2005 |
Differences in type I diabetes mellitus of young adults with and without thyroid autoimmunity.
This work was intended to study if the coexistence of thyroid and Langerhans islets autoimmunity is associated with a different nature and course of diabetes in young adult diabetic patients. We followed the laboratory and clinical course of diabetes and the thyroid gland status of 47 young adults with Type I diabetes over a 9-year period starting from the onset of diabetes (ranging from 18 to 35 years of age). The patients were divided into subgroup I (with thyroid peroxidase and thyroglobulin antibodies, n = 13), subgroup II (thyroid peroxidase antibody only, n = 10), and subgroup III (without thyroid autoimmunity, n = 24). Out of the 22 females followed, 10 (46 %) and 5 (23 %) were in subgroups with thyroid autoimmunity (TA), I and II, respectively. On the contrary, out of the 25 men followed, 17 (68 %) were in group III. Within the 9 years, insulin secretion nearly ceased (C-peptide < 0.03 nmol/L) in all of the patients of subgroup I and 70 % of subgroup II, but only in 46 % of patients in subgroup III (I : II p < 0.01, I : III, p < 0.01, II : III, p < 0.05). The cumulative incidence of antiGAD > 1 U/mL (CIS, RIA) in subgroup I was higher (92 %) than in subgroups II (80 %) and III (53 %); I : III, p < 0.05. The cumulative incidence of tyrosine phosphatase antibodies (anti-IA2, BRAHMS, RIA) was insignificantly higher in subgroups I and II when compared with subgroup III (62 %, 60 %, and 42 %). The study of organ-specific and systemic autoantibodies showed their highest cumulative incidence in subgroup I, i.e., in patients with the most expressed manifestations of TA and the lowest one in subgroup III, i.e., diabetic patients without TA. Our results suggest that overall thyroid autoimmunity in young adult patients with Type I diabetes was associated not only with female gender, but also with more pronounced Langerhans islets autoimmunity and significantly faster cessation of endogenous insulin secretion; it was associated with therapeutical doses of insulin as well. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; C-Peptide; Diabetes Complications; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Longitudinal Studies; Male; Prospective Studies; Statistics, Nonparametric; Thyroid Function Tests; Thyroiditis, Autoimmune | 2005 |
The immunological effect of photopheresis in children with newly diagnosed type 1 diabetes.
Photopheresis has been claimed to have immune-modulating effects, but the mechanisms of action are unknown. This study investigated the immune effect of photopheresis in children with type 1 diabetes, with a focus on the balance of Th1- and Th2-like cytokines. Ten children with newly diagnosed type 1 diabetes (10-17 y) were treated with five double treatments of photopheresis and 10 children matched for disease, age, and gender were given placebo tablets and sham pheresis. Expression of IFN-gamma and IL-4 mRNA was determined by real-time reverse-transcriptase polymerase chain reaction (RT-PCR) and secretion of IFN-gamma, IL-10, and IL-13 in cell-culture supernatants by ELISA after stimulation with glutamic acid decarboxylase (GAD65) (a.a. 247-279), the ABBOS peptide (a.a. 152-169), insulin, phytohemagglutinin (PHA), and keyhole limpet hemocyanin (KLH). Photopheresis changed antigen-stimulated immune balance in line with a Th2-like shift. Thus, the ratio of IFN-gamma/IL-4 mRNA expression after in vitro stimulation with a peptide of the autoantigen GAD65 was reduced after treatment in the photopheresis group. The IFN-gamma/IL-4 mRNA expression ratio after in vitro stimulation with insulin was also lower in children treated with photopheresis compared with the placebo group. Photopheresis has an immune-modulating effect in children with type 1 diabetes, causing a Th2-like deviation. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Humans; Islets of Langerhans; Photopheresis | 2005 |
Proinsulin levels and the proinsulin:c-peptide ratio complement autoantibody measurement for predicting type 1 diabetes.
We investigated whether random proinsulin levels and proinsulin:C-peptide ratio (PI:C) complement immune and genetic markers for identifying relatives at high risk of type 1 diabetes.. During an initial sampling, random glycaemia, proinsulin, PI:C and HLA DQ genotype were determined in 561 non-diabetic first-degree relatives who had been positive for islet autoantibodies on one or more occasions and in 561 age- and sex-matched persistently antibody-negative relatives.. During follow-up (median 62 months), 46 relatives with antibodies at entry developed type 1 diabetes. At baseline, antibody-positive relatives (n=338) had higher PI:C values (p<0.001) than antibody-negative subjects with (n=223) or subjects without (n=561) later seroconversion. Proinsulin and PI:C were graded according to risk of diabetes as expressed by positivity for (multiple) antibodies or IA-2 antibodies, especially in persons carrying the high-risk HLA DQ2/DQ8 genotype and in prediabetic relatives. In the presence of multiple or IA-2 antibodies, a PI:C ratio exceeding percentile 66 of all antibody-negative relatives at entry (n=784) conferred a 5-year diabetes risk of 50% and 68%, respectively (p<0.001 vs 13% for same antibody status with PI:C Topics: Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA-DQ Antigens; Hormones; Humans; Infant; Infant, Newborn; Islets of Langerhans; Male; Middle Aged; Pedigree; Prediabetic State; Predictive Value of Tests; Proinsulin | 2005 |
Incidence of type 1 and type 2 diabetes in adults aged 30-49 years: the population-based registry in the province of Turin, Italy.
Incidence of type 1 diabetes is considered to be low in adults, but no study has been performed in Mediterranean countries.. We extended the study base of the registry of the province of Turin, Italy, to subjects aged 30-49 years in the period 1999-2001 to estimate the incidences of type 1 and type 2 diabetes. Diagnosis of type 1 diabetes was based on permanent insulin treatment or a fasting C-peptide level < or =0.20 nmol/l or islet cell (ICA) or GAD (GADA) antibody positivities.. We identified 1,135 case subjects with high completeness of ascertainment (99%), giving an incidence rate of 58.0 per 100,000 person-years (95% CI 54.7-61.5). The incidence of type 1 diabetes was 7.3 per 100,000 person-years (6.2-8.6), comparable with the rates in subjects aged 0-14 and 15-29 years (10.3 [9.5-11.2] and 6.8 [6.3-7.4]). Male subjects had a higher risk than female subjects for both type 1 (rate ratio [RR] 1.70 [95% CI 1.21-2.38]) and type 2 (2.10 [1.84-2.40]) diabetes. ICA and/or GADA positivities were found in 16% of the cohort. In logistic regression, variables independently associated with autoimmune diabetes were age 30-39 years (odds ratio [OR] 2.39 [95% CI 1.40-4.07]), fasting C-peptide <0.60 nmol/l (3.09 [1.74-5.5]), and BMI <26 kg/m2 (2.17 [1.22-3.85]).. Risk of type 1 diabetes between age 30 and 49 years is similar to that found in the same area between age 15 and 29 years. Further studies are required to allow geographical comparisons of risks of both childhood and adulthood autoimmune diabetes, the latter being probably higher than previously believed. Topics: Adult; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glutamate Decarboxylase; Humans; Incidence; Insulin; Islets of Langerhans; Italy; Logistic Models; Male; Odds Ratio; Registries; Retrospective Studies; Risk | 2005 |
Pancreatic elastase-1 in stools, a marker of exocrine pancreas function, correlates with both residual beta-cell secretion and metabolic control in type 1 diabetic subjects: response to Cavalot et al.
Topics: Adult; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Biomarkers; C-Peptide; Carrier Proteins; Case-Control Studies; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Feces; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Pancreatic Elastase | 2005 |
Pancreatic elastase-1 in stools, a marker of exocrine pancreas function, correlates with both residual beta-cell secretion and metabolic control in type 1 diabetic subjects: response to Mueller et al.
Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Biomarkers; C-Peptide; Carrier Proteins; Case-Control Studies; Diabetes Mellitus, Type 1; Feces; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Pancreatic Elastase | 2005 |
Improvement of sample pretreatment prior to analysis of C-peptide in serum by isotope-dilution liquid chromatography/tandem mass spectrometry.
Topics: C-Peptide; Chromatography, High Pressure Liquid; Clinical Laboratory Techniques; Deuterium; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Isotope Labeling; Specimen Handling; Spectrometry, Mass, Electrospray Ionization | 2005 |
CD3-antibody therapy in new-onset type 1 diabetes mellitus.
Topics: Adolescent; C-Peptide; CD3 Complex; Child; Diabetes Mellitus, Type 1; Humans; Immunoglobulin G | 2005 |
Insulin independence of unstable diabetic patient after single living donor islet transplantation.
Current success in islet transplantation will lead to a donor shortage. Living donor islet transplantation could be an alternative approach to expand the potential donor pool. In this study we describe the first successful living donor islet transplantation for unstable diabetes, performed at Kyoto University Hospital on January 19, 2005.. The donor was a healthy 56-year-old woman and mother of the recipient. The recipient was a 27-year-old woman with insulin-dependent diabetes since the age of 15 years. She experienced frequent hypoglycemic unawareness episodes. Her blood glucose concentration was difficult to control and C-peptide level was negative after glucagon stimulation. She needed an average 28 of units of insulin per day. The donor underwent a distal pancreatectomy and islets were isolated from the resected pancreas graft. The total islet yield was 408,114 islet equivalents and isolated islets were immediately transplanted into the recipient's liver.. After transplant, the blood glucose level of the recipient was tightly controlled without hypoglycemic episodes. She was discharged on day 37 with a normal oral glucose tolerance test (OGTT). The recipient remained insulin-independent for >3 months, since day 22 posttransplant. The donor's postoperative clinical course was uneventful. She was discharged on postoperative day 18 and returned to her job within 1 month.. We report the first successful living donor islet transplantation for the treatment of unstable diabetes. We believe that living donor islet transplantation may become an option in the treatment of insulin-dependent diabetes. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Living Donors; Middle Aged; Pancreatectomy; Tissue and Organ Harvesting; Treatment Outcome | 2005 |
C-peptide and glucose values in the peritransplant period after intraportal islet infusions in type 1 diabetes.
Successful islet allograft transplantation has been achieved worldwide. This study aimed at evaluating the relationship between peritransplant C-peptide (CP) values and long-term allograft function.. We measured CP-to-glucose ratio (CPGR) in intraportal samples pre- and postinfusion, and in peripheral circulation at baseline pretransplant and at 1, 3, 6, 12, 72 hours, 1 week, and 15 and 30 days after first and second infusion in 13 islet allograft recipients. Peritransplant treatment included intravenous (IV) 5% dextrose in saline in all patients. We compared portal CPGR to insulin reduction (%) at 30 days after each infusion, and at 1 year after second infusion.. CPGR peaked between the immediate postinfusion and 3 hours and decreased at 12 hours. At 1 week, CPGR was 0.76 +/- 0.45 and 1.44 +/- 0.37 after first and second infusion, respectively. CPGR at 30 days after second infusion doubled compared to first infusion (P < .001). There was no correlation between peak CPGR and insulin reduction percent at any time point. One patient experienced hypoglycemia (47 mg/dL) 1 hour after second infusion.. There was no relationship between the CP values in the peritransplant period and long-term graft function or success rate. The early peak in the C-peptide levels is indicative of a significant insulin release after each islet infusion. For this reason, it is important to carefully monitor serum glucose levels in the peritransplant period (hourly for the first 6 hours) and to maintain an IV glucose infusion to avoid hypoglycemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans Transplantation; Portal System; Transplantation, Homologous; Treatment Outcome | 2005 |
Simple evaluation of engraftment by secretory unit of islet transplant objects for living donor and cadaveric donor fresh or cultured islet transplantation.
Evaluation of engraftment is important to assess the success of islet transplantation. Recently we developed secretory unit of islet transplant objects (SUITO) index for simple evaluation of engraftment. Assuming that normal subjects aged <40 years have 100% pancreatic beta-cell function, SUITO index was calculated by the formula: 1500 x fasting C-peptide immunoreactivity [ng/dL]/(fasting blood glucose [mg/dL] - 63). In this study, we compared the efficacy of islet transplantation from cadaveric and living donors using the SUITO index.. We performed eight islet transplantations with non-heart-beating donors (NHBDs) into five patients. Two patients received fresh islets once, one patient received fresh islets twice, one patient received cultured islets once, and one patient received cultured islets twice plus fresh islets once. In addition, one patient received fresh islets from a living donor. We calculated the SUITO index from postoperative days 3 to 30 for each case.. Mean SUITO index after one fresh islet transplant was 11.7 +/- 1.0, after two fresh islet transplants was 28.5 +/- 3.4, after one cultured islet transplant was 2.1 +/- 0.4, after two cultured islet transplant was 12.1 +/- 1.9, and after two cultured islet transplant plus one fresh islet transplant was 26.7 +/- 1.7. The mean SUITO index after single living donor islet transplant was 40.7 +/- 2.6, which was significantly higher compared with all other groups. Insulin independence was obtained when the SUITO index was >26, which might reflect that 26% beta-cell mass was required for insulin independence.. SUITO index is useful to evaluate islet engraftment and to predict the possibility of insulin independence. Topics: Blood Glucose; C-Peptide; Cadaver; Cells, Cultured; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Living Donors; Postoperative Period; Tissue Donors | 2005 |
Metabolic effect of sirolimus versus mycophenolate mofetil on pancreatic graft function in the early posttransplant period.
Metabolic effects of immunosuppressive agents are of great importance in pancreas or islet transplantation. The aim of our study was to compare effects of tacrolimus-based immunosuppression in conjunction with sirolimus (RAPA) versus mycophenolate mofetil (MMF) on glucose metabolism in type 1 diabetic recipients following a simultaneous pancreas and kidney transplantation (SPK). We examined 30 insulin-independent patients after SPK with venous systemic drainage of the pancreatic graft. All recipients had good kidney graft function. Fasting glycemia, insulin levels, glycosylated hemoglobin (HbA(lc)), standard intravenous glucose tolerance test (IVGTT), and trough RAPA levels were assessed in pancreas recipients before elective steroid withdrawal. Insulin sensitivity was evaluated using the homeostasis model assessment (HOMA-IR). The groups did not differ in age, BMI, posttransplant period, steroid daily dose, HbA(lc), and fasting glycemia. We did not find any significant difference in the IVGTT response. Area under the curve of insulin levels during IVGTT and HOMA-IR were significantly lower in the RAPA group. Trough levels of RAPA had no significant impact on any of the examined parameters. Glucose tolerance measured with the use of IVGTT was similar in patients treated with RAPA and MMF. However, recipients on sirolimus treatment had significantly lower insulinemia during the test and consequently more favorable indices of insulin action as assessed by HOMA-IR. Topics: Area Under Curve; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Glycated Hemoglobin; Humans; Insulin; Kidney Transplantation; Mycophenolic Acid; Pancreas Transplantation; Sirolimus | 2005 |
Quality of life after simultaneous pancreas-kidney transplantation.
Even recipients with satisfactory function of transplanted pancreas and kidney may show physical and/or social disability due to diabetic complications. Our aims were to evaluate diabetic complications influencing recipient quality of life and to assess patients' psychosociological status. Nineteen patients with functioning grafts who consented to take part in the study, underwent clinical evaluation and answered questions regarding their quality of life. Results showed excellent endocrine pancreatic function in 17 patients. In most recipients, insulin activity and C-peptide levels were elevated owing to systemic venous drainage. Opthalmological examination revealed blindness in 7 patients (in 4 cases with onset following SPKTx) and retinopathy in 13 patients (in 5 cases it appeared after SPKTx). Assessment of the cardiovascular system revealed satisfactory cardiac function in 16 of 19 patients; 4 patients underwent amputation of a lower limb following SPKTx. All 19 recipients admitted to a great benefit of transplantation; most patients declared ability to organize their life activity and social functions and 4 had regular employment. Conversely, most patients were afraid of graft loss, and half were often sad and even depressed. Topics: Blindness; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Employment; Humans; Insulin; Insulin Secretion; Kidney Failure, Chronic; Kidney Transplantation; Pancreas Transplantation; Postoperative Complications; Quality of Life | 2005 |
Latent autoimmune diabetes in adults: definition, prevalence, beta-cell function, and treatment.
Latent autoimmune diabetes in adults (LADA) is a disorder in which, despite the presence of islet antibodies at diagnosis of diabetes, the progression of autoimmune beta-cell failure is slow. LADA patients are therefore not insulin requiring, at least during the first 6 months after diagnosis of diabetes. Among patients with phenotypic type 2 diabetes, LADA occurs in 10% of individuals older than 35 years and in 25% below that age. Prospective studies of beta-cell function show that LADA patients with multiple islet antibodies develop beta-cell failure within 5 years, whereas those with only GAD antibodies (GADAs) or only islet cell antibodies (ICAs) mostly develop beta-cell failure after 5 years. Even though it may take up to 12 years until beta-cell failure occurs in some patients, impairments in the beta-cell response to intravenous glucose and glucagon can be detected at diagnosis of diabetes. Consequently, LADA is not a latent disease; therefore, autoimmune diabetes in adults with slowly progressive beta-cell failure might be a more adequate concept. In agreement with proved impaired beta-cell function at diagnosis of diabetes, insulin is the treatment of choice. Topics: Adult; Age of Onset; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Glucose; Humans; Insulin; Islets of Langerhans; Prospective Studies; Time Factors | 2005 |
Feasibility, safety, and efficacy of percutaneous transhepatic injection of beta-cell grafts.
To evaluate the safety, feasibility, and clinical efficacy of percutaneous transhepatic injection of beta-cell grafts in patients with type 1 diabetes mellitus.. Between December 2001 and November 2003, 15 patients with C-peptide-negative type 1 diabetes underwent 31 percutaneous injections for intraportal implantation of beta-cell grafts. Grafts consisted of cultured beta-cell preparations as previously described. In 13 cases, the transplant procedure was done under sedation, whereas in 18 cases, general anesthesia was given. In all procedures, percutaneous access to the right portal vein occurred under ultrasound (US) guidance with use of a microbore puncture needle. The subsequent catheterization of the main portal vein was performed under fluoroscopic and angiographic control with use of a microbore delivery catheter and guide wire. Clinical, biochemical, and radiologic evaluation was performed before and after the procedure.. In all cases, it was possible to access the portal vein (median number of needle passes, 1; range, 1-6). The volume of cultured beta-cell grafts injected for each transplantation averaged 0.58 mL (range, 0.26-1.60 mL) and the mean recorded procedure time (from puncture to catheter withdrawal) was 19 minutes (range, 10-80 min). Three patients presented with transient abdominal pain immediately after the procedure; postprocedural duplex US of the liver revealed a patent portal vein and end branches in all cases and a minor perihepatic fluid collection in another three patients. From the end of week 1 to week 3, a mean 3.8-fold increase in liver aminotransferase levels was measured in all recipients after the first implantation session. A similar increase was seen in only one patient after a second transplantation session. At 6 months after transplantation, 13 of 15 patients (86%) had a functioning graft with plasma C-peptide levels greater than 0.5 ng/mL.. The combined US, fluoroscopic, and angiographic monitoring of percutaneous transhepatic injection with use of a microbore delivery catheter is a safe and reproducible radiologic procedure for transplantation of beta-cell grafts in diabetic patients. Increased posttransplantation C-peptide levels, which demonstrate acceptable graft function, can be obtained. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diagnostic Imaging; Feasibility Studies; Female; Fluoroscopy; Humans; Injections; Insulin-Secreting Cells; Liver; Liver Function Tests; Male; Middle Aged; Portal Vein; Transaminases; Transplantation, Homologous; Treatment Outcome; Vascular Patency | 2005 |
Immunosuppression and procedure-related complications in 26 patients with type 1 diabetes mellitus receiving allogeneic islet cell transplantation.
The success of sirolimus and low-dose tacrolimus in islet cell transplantation has influenced many transplant centers to utilize this novel regimen. The long-term safety and tolerability of this steroid-free immunosuppressive protocol for allogeneic islet transplantation has yet to be determined.. We transplanted 26 adult patients with long standing type 1 diabetes mellitus between April 2000 and June 2004. Immunosuppression consisted of induction with daclizumab and maintenance therapy with tacrolimus and sirolimus. Adverse events (AEs) in patients were followed and graded using the Common Terminology Criteria for Adverse Events, version 3.0 (National Cancer Institute).. To date, the majority of patients were able to remain on the immunosuppression combination for up to 22+/-11 months. Four patients were successfully converted to Mycophenolate Mofetil due to tacrolimus-related toxicity. Withdrawal from immunosuppression was decided in four patients due to hypereosinophilic syndrome, parvovirus infection, aspiration pneumonia, and severe depression, respectively. Six patients required filgrastim therapy for neutropenia. Transient elevation of liver enzymes was observed in most patients early after islet infusion. Increased LDL in 20 patients required medical treatment.. There was a varying range of AEs, most of them mild and self-limiting; however, some required urgent medical attention. The majority of patients were able to tolerate and remain on this effective regimen. To date, no deaths, cytomegalovirus disease, graft-versus-host disease, or posttransplant lymphoproliferative disease has been observed. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Postoperative Complications; Retrospective Studies; Transplantation, Homologous | 2005 |
Minimal focal steatosis of liver after islet transplantation in humans: a long-term study.
Several reports have been published on islet transplantation in humans, but few data are available on the effect of islet infusion on the hepatic structure. Our aim was to evaluate in a longitudinal study the impact on the liver of intrahepatic islet transplantation. Clinical outcome and liver imaging were evaluated in 31 cases of islet-kidney transplantation (follow-up 38 +/- 4 months, range 12-96 months). Patients were divided into three groups: full function (FF, 9 cases: established insulin independence); partial function (PF, 16 cases: transient insulin independence, prolonged C-peptide secretion): no function (NF, 6 cases: exhaustion of C-peptide secretion within the first year). Upper abdomen sonogram was regularly performed during the whole follow-up period. Percutaneous liver biopsy was performed in case of echographic abnormalities. Multiple small areas of focal hyperechogenicity were observed in nine cases after 6-12 months. These findings were observed only in FF (two) and in PF (seven) patients. Fasting C-peptide levels at the time of echography were higher in negative than in positive patients (2.42 +/- 0.16 vs. 1.51 +/- 0.10 ng/ml, p = 0,0001). Liver biopsies showed focal macrovesicular steatosis, surrounded by normal liver parenchyma. Normal liver function was maintained. In conclusion, our results indicate that islet transplantation can lead to structural changes of the liver parenchyma (focal steatosis). It is more often observed in patients with partial function. Sonogram can be considered a specific method to reveal liver changes after islet transplantation. Topics: Adult; Biopsy; C-Peptide; Cell Movement; Diabetes Mellitus, Type 1; Fatty Liver; Follow-Up Studies; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Liver; Longitudinal Studies; Pancreas; Treatment Outcome; Ultrasonography, Doppler, Color | 2005 |
Generation of islet-like hormone-producing cells in vitro from adult human pancreas.
Transplantation of pancreatic islets can provide long-lasting insulin independence for diabetic patients, but the current islet supply is limited. Here we describe a new in vitro system that utilizes adult human pancreatic islet-enriched fractions to generate hormone-producing cells over 3-4 weeks of culture. By labeling proliferating cells with a retrovirus-expressing green fluorescent protein, we show that in this system hormone-producing cells are generated de novo. These hormone-producing cells aggregate to form islet-like cell clusters. The cell clusters, when tested in vitro, release insulin in response to glucose and other secretagogues. After transplantation into immunodeficient, nondiabetic mice, the islet-like cell clusters survive and release human insulin. We propose that this system will be useful as an experimental tool for investigating mechanisms for generating new islet cells from the postnatal pancreas, and for designing strategies to generate physiologically competent pancreatic islet cells ex vivo. Topics: Animals; C-Peptide; Cell Culture Techniques; Cell Proliferation; Cells, Cultured; Diabetes Mellitus, Type 1; Glucose; Green Fluorescent Proteins; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Mice, Inbred NOD; Mice, SCID; Phenotype | 2005 |
Abnormal ghrelin secretion in new onset childhood Type 1 diabetes.
Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Ghrelin; Humans; Hypoglycemic Agents; Insulin; Peptide Hormones | 2004 |
C-peptide is the appropriate outcome measure for type 1 diabetes clinical trials to preserve beta-cell function: report of an ADA workshop, 21-22 October 2001.
The underlying cause of type 1 diabetes, loss of beta-cell function, has become the therapeutic target for a number of interventions in patients with type 1 diabetes. Even though insulin therapies continue to improve, it remains difficult to achieve normal glycemic control in type 1 diabetes, especially long term. The associated risks of hypoglycemia and end-organ diabetic complications remain. Retention of beta-cell function in patients with type 1 diabetes is known to result in improved glycemic control and reduced hypoglycemia, retinopathy, and nephropathy. To facilitate the development of therapies aimed at altering the type 1 diabetes disease process, an American Diabetes Association workshop was convened to identify appropriate efficacy outcome measures in type 1 diabetes clinical trials. The following consensus emerged: While measurements of immune responses to islet cells are important in elucidating pathogenesis, none of these measures have directly correlated with the decline in endogenous insulin secretion. HbA(1c) is a highly valuable clinical measure of glycemic control, but it is an insensitive measure of beta-cell function, particularly with the currently accepted standard of near-normal glycemic control. Rates of severe hypoglycemia and diabetic complications ultimately will be improved by therapies that are effective at preserving beta-cell function but as primary outcomes require inordinately large and protracted trials. Endogenous insulin secretion is assessed best by measurement of C-peptide, which is cosecreted with insulin in a one-to-one molar ratio but unlike insulin experiences little first pass clearance by the liver. Measurement of C-peptide under standardized conditions provides a sensitive, well accepted, and clinically validated assessment of beta-cell function. C-peptide measurement is the most suitable primary outcome for clinical trials of therapies aimed at preserving or improving endogenous insulin secretion in type 1 diabetes patients. Available data demonstrate that even relatively modest treatment effects on C-peptide will result in clinically meaningful benefits. The development of therapies for addressing this important unmet clinical need will be facilitated by trials that are carefully designed with beta-cell function as determined by C-peptide measurement as the primary efficacy outcome. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Predictive Value of Tests; Prognosis; Reproducibility of Results; Treatment Outcome | 2004 |
Acute, local effects of iontophoresed insulin and C-peptide on cutaneous microvascular function in Type 1 diabetes mellitus.
The aim of the present study was to demonstrate acute, local vasodilatatory effects of insulin and C-peptide on cutaneous microvascular function in Type 1 diabetic subjects. There are no published data available examining physiological effects of C-peptide delivered in this way.. The study included 20 participants with C-peptide-deficient Type 1 diabetes mellitus. Cutaneous microvascular function was assessed on the forearm using laser Doppler velocimetry. Insulin, C-peptide, acetylcholine (ACh), sodium nitroprusside (SNP) and saline were delivered through the skin using iontophoresis. The response was measured as percentage increase in flux above baseline.. C-peptide delivered by iontophoresis produced a vasodilatatory response greater than the response to saline (289.5 +/- 265.9% vs. 105.1 +/- 163.6%, P = 0.003). The response to C-peptide was also shown to be dose dependent. Further, the size of the response to C-peptide correlated well with the size of the response to the endothelium-dependent vasodilatator ACh (r = 0.666, P = 0.001) but not with the size of the response to the endothelium-independent vasodilator SNP (r = 0.345, P > 0.05).. Physiological effects of C-peptide on cutaneous microvascular function could be demonstrated in individuals with Type 1 diabetes. The results support both physiological activity of C-peptide and an endothelium-dependent mechanism similar to that of ACh. The technique reported may be useful in investigating vasoactive actions of C-peptide in a safe and non-invasive way. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Humans; Hypoglycemic Agents; Insulin; Iontophoresis; Laser-Doppler Flowmetry; Male; Microcirculation; Middle Aged; Pilot Projects; Skin; Vasodilation | 2004 |
Prevalence of hepatic steatosis after islet transplantation and its relation to graft function.
Islet allotransplantation can provide insulin independence in selected individuals with type 1 diabetes. The long-term effects of these transplants on the liver are unknown. Recently, two cases of periportal steatosis after islet transplantation have been described. In this study, we performed ultrasound and magnetic resonance imaging (MRI) in 30 C-peptide-positive islet transplant recipients to detect steatosis and to explore the association of the radiological findings with clinical and metabolic factors. Steatosis was observed on MRI in six (20%) subjects. Histological findings of hepatic steatosis concurred with the imaging findings. Steatosis completely resolved in one subject whose graft failed. More subjects with steatosis required supplementary exogenous insulin than not (67 vs. 21%; P < 0.05). The clinical features of subjects with and without steatosis were otherwise similar, although C-peptide levels were higher in insulin-independent subjects with steatosis (0.98 +/- 0.12 vs. 0.70 +/- 0.18 nmol/l; P = 0.05), despite similar blood glucose levels. Serum triglycerides and the use of exogenous insulin were associated with increased odds of steatosis in a logistic regression model (chi(2) [degrees freedom] = 13.6 [2]); P = 0.001). MRI-detected steatosis is a common finding; the steatosis appears to be due to a paracrine action of insulin secreted from intrahepatic islets. Hepatic steatosis may be associated with insulin resistance or graft dysfunction. Topics: Adult; Biopsy; C-Peptide; Diabetes Mellitus, Type 1; Fatty Liver; Female; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Magnetic Resonance Imaging; Male; Middle Aged; Prevalence; Ultrasonography | 2004 |
Adult-onset atypical (type 1) diabetes: additional insights and differences with type 1A diabetes in a European Mediterranean population.
In 1997, the American Diabetes Association proposed two subcategories for type 1 diabetes: type 1A or immunomediated diabetes and type 1B or idiopathic diabetes characterized by negative beta-cell autoimmunity markers, lack of association with HLA, and fluctuating insulinopenia. The aim of this study was to examine clinical characteristics, beta-cell function, HLA typing, and mutations in maturity-onset diabetes of the young (MODY) genes in patients with atypical type 1 diabetes (type 1 diabetes diagnosed at onset, without pancreatic autoantibodies and fluctuating insulinopenia).. Eight patients with atypical type 1 diabetes (all men, 30.7 +/- 7.6 years) and 16 newly diagnosed age- and sex-matched patients with type 1A diabetes were studied retrospectively. Islet cell, GAD, tyrosine phosphatase and insulin antibodies, and basal and stimulated plasma C-peptide were measured at onset and after 1 year. HLA-DRB1-DQA1-DQB1 typing and screening for mutations in the HNF-1alpha and HNF-4alpha genes were performed from genomic DNA.. Atypical patients displayed significantly higher BMI and better beta-cell function at onset and after 12 months. Three patients carried protective or neutral type 1 diabetes haplotypes, five patients displayed heterozygosity for susceptible and protective haplotypes, and seven patients showed Asp(beta57). We found a nondescribed variant Pro436Ser in exon 10 of the HNF-4alpha gene in one atypical patient without susceptible haplotypes.. In our population, there are atypical forms of young adult-onset ketosis-prone diabetes initially diagnosed as type 1 diabetes, differing from type 1 diabetes in the absence of beta-cell autoimmunity, persistent beta-cell function capacity, fluctuating insulin requirements and ketosis-prone episodes, as well as clinical features of type 2 diabetes. Only one subgroup could be strictly classified as having type 1B diabetes. Additional information is still needed to improve our understanding of the mechanisms that finally lead to the disease. Topics: Adult; Age of Onset; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Male; Mediterranean Region; Retrospective Studies; Time Factors | 2004 |
The case for intravenous arginine stimulation in lieu of mixed-meal tolerance tests as outcome measure for intervention studies in recent-onset type 1 diabetes.
Topics: Arginine; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Injections, Intravenous; Postprandial Period; Reproducibility of Results; Treatment Outcome | 2004 |
Influence of islet transportation on pancreatic islet allotransplantation in type 1 diabetic patients within the Swiss-French GRAGIL network.
The influence of islet transportation on pancreatic islet allotransplantation in type 1 diabetic patients was evaluated within the GRAGIL network.. From December 2001 to April 2003, 16 human pancreatic islet transplants were performed in 9 type 1 diabetic patients with an established kidney graft (functioning for at least 6 months) in four centers of the GRAGIL network. Islet isolation was performed in a core laboratory in Geneva, and the islet preparations were shipped by ambulance to each center for transplantation. One month after transplantation, the efficiency of the graft was assessed according to islet transportation time (ITT): ITT less than 2 hours (group 1, n=5), and ITT greater than 4.5 hours (group 2, n=4, mediant 5 hours).. Primary graft dysfunction was observed in one patient in group 1 after one month. Two patients became insulin independent in groups 1 and 2. All other patients in both groups had a plasma C-peptide level greater than 0.5 ng/ml. The HbA1c level and the exogenous insulin needs decreased in both groups.. ITT does not seem to influence the efficiency of pancreatic islet allotransplantation in type 1 diabetic patients. These results emphasize the scope for multicenter networks such as the GRAGIL group. Topics: Adult; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; France; Glycated Hemoglobin; Graft Survival; Humans; Islets of Langerhans Transplantation; Male; Middle Aged; Switzerland; Time Factors; Tissue and Organ Procurement; Transportation | 2004 |
Cytokine profile in children during the first 3 months after the diagnosis of type 1 diabetes.
Type 1 diabetes is an autoimmune disease with an inflammatory process directed against the beta cells in pancreas. This investigation aimed at studying the immune response during the first 3 months after the diagnosis of type 1 diabetes, with focus on the balance of T-helper 1 (Th1)- and Th2-like cytokines, produced spontaneously and in response to relevant autoantigens. Peripheral blood mononuclear cells (PBMCs) were collected from type 1 diabetic children (10-17 years) at 5, 20, 35 and 90 days after diagnosis. Expression of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) mRNA were detected by real-time reverse transcriptase polymerase chain reaction and IFN-gamma, IL-10 and IL-13 by enzyme-linked immunosorbent assay in cell supernatant after stimulation with a glutamic acid decarboxylase 65 (GAD(65))-peptide [amino acid (a.a.) 247-279], insulin, the ABBOS-peptide (a.a. 152-169), phytohaemagglutinin and keyhole limpet haemocyanin. Spontaneous and antigen-induced expression and secretion of cytokines were low at the diagnosis of type 1 diabetes. During the first month, after diagnosis, the GAD(65)-peptide caused an increased ratio of IFN-gamma/IL-4 mRNA expression (P < 0.05) and increased secretion of IFN-gamma (P = 0.07). Expression of IFN-gamma mRNA did also increase from stimulation with insulin (P < 0.05), even though cytokine secretion remained low. Thus, duration after diagnosis as well as metabolic state should be carefully considered both in studies of the pathogenesis of type 1 diabetes and in immune intervention studies at onset. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Insulin; Interferon-gamma; Interleukin-4; Islets of Langerhans; Male; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Th1 Cells; Th2 Cells; Time Factors | 2004 |
Molecular alterations underlie nodal and paranodal degeneration in type 1 diabetic neuropathy and are prevented by C-peptide.
To explore the molecular abnormalities underlying the degeneration of the node of Ranvier, a characteristic aberration of type 1 diabetic neuropathy, we examined in type 1 BB/Wor and type 2 BBZDR/Wor rats changes in expression of key molecules that make up the nodal and paranodal apparatus of peripheral nerve. Their posttranslational modifications were examined in vitro. Their responsiveness to restored insulin action was examined in type 1 animals replenished with proinsulin C-peptide. In sciatic nerve, the expression of contactin, receptor protein tyrosine phosphatase beta, and the Na(+)-channel beta(1) subunit, paranodal caspr and nodal ankyrin(G) was unaltered in 2-month type 1 diabetic BB/Wor rats but significantly decreased after 8 months of diabetes. These abnormalities were prevented by C-peptide administered to type 1 BB/Wor rats and did not occur in duration- and hyperglycemia-matched type 2 BBZDR/Wor rats. The expression of the alpha-Na(+)-channel subunit was unaltered. In SH-SY5Y cells, only the combination of insulin and C-peptide normalized posttranslational O-linked N-acetylglucosamine modifications and maximized serine phosphorylation of ankyrin(G) and p85 binding to caspr. The beneficial effects of C-peptide resulted in significant normalization of the nerve conduction deficits. These data describe for the first time the progressive molecular aberrations underlying nodal and paranodal degenerative changes in type 1 diabetic neuropathy and demonstrate that they are preventable by insulinomimetic C-peptide. Topics: Animals; Blood Glucose; Blotting, Western; C-Peptide; Cell Line, Tumor; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Glycated Hemoglobin; Humans; Immunohistochemistry; Insulin; Nerve Degeneration; Neural Conduction; Peripheral Nervous System Diseases; Protein Processing, Post-Translational; Ranvier's Nodes; Rats; Rats, Inbred BB; Sciatic Nerve | 2004 |
Transient chylomicronemia preceding the onset of insulin-dependent diabetes in a young girl with no humoral markers of islet autoimmunity.
We investigated the possible causes of diabetes in a young child who presented with hyperglycemia associated with severe hypertriglyceridemia (>166 mmol/l), hypercholesterolemia (>38 mmol/l) and fasting chilomicrons.. The patient did not have any of the HLA and autoantibody markers typically associated with type 1 diabetes. A glucose clamp failed to demonstrate insulin resistance (peripheral glucose utilization rate (M)=4.3 mg/kg per min) and there was no family history of type 2 diabetes or maturity onset diabetes in youth. Both fasting and stimulated C-peptide levels, including those in response to i.v. glucagon, were below the limit of detection. This is consistent with loss of beta-cell function. The family history did not reveal the existence of relatives with lipid abnormalities, coronary heart disease, and pancreatitis. We did not find any abnormality of plasma apoCII, lipoproteinlipase and hepatic lipase activities. The patients had a epsilon3/epsilon3 apoE genotype and she rapidly cleared an oral fat load after normalization of plasma lipids.. The mild hyperglycemia seems an unlikely explanation for both the severe hypertriglyceridemia and chylomicronemia. A more plausible explanation is transient lipoproteinlipase deficiency. This rare condition, occasionally associated with a high-fat diet, could have caused the rapid and dramatic hypertriglyceridemia observed in this patient, which in turn might have led to the beta-cell destruction by direct lipid toxicity. Topics: Autoantibodies; Autoimmunity; C-Peptide; Child; Chylomicrons; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Glucose Clamp Technique; Humans; Hypercholesterolemia; Hyperglycemia; Hypertriglyceridemia; Islets of Langerhans; Lipoprotein Lipase | 2004 |
Experimental rat models of types 1 and 2 diabetes differ in sympathetic neuroaxonal dystrophy.
Dysfunction of the autonomic nervous system is a recognized complication of diabetes, ranging in severity from relatively minor sweating and pupillomotor abnormality to debilitating interference with cardiovascular, genitourinary, and alimentary dysfunction. Neuroaxonal dystrophy (NAD), a distinctive distal axonopathy involving terminal axons and synapses, represents the neuropathologic hallmark of diabetic sympathetic autonomic neuropathy in man and several insulinopenic experimental rodent models. Although the pathogenesis of diabetic sympathetic NAD is unknown, recent studies have suggested that loss of the neurotrophic effects of insulin and/or insulin-like growth factor-I (IGF-I) on sympathetic neurons rather than hyperglycemia per se, may be critical to its development. Therefore, in our current investigation we have compared the sympathetic neuropathology developing after 8 months of diabetes in the streptozotocin (STZ)-induced diabetic rat and BB/ Wor rat, both models of hypoinsulinemic type 1 diabetes, with the BBZDR/Wor rat, a hyperglycemic and hyperinsulinemic type 2 diabetes model. Both STZ- and BB/Wor-diabetic rats reproducibly developed NAD in nerve terminals in the prevertebral superior mesenteric sympathetic ganglia (SMG) and ileal mesenteric nerves. The BBZDR/Wor-diabetic rat, in comparison, failed to develop superior mesenteric ganglionic NAD in excess of that of age-matched controls. Similarly, NAD which developed in axons of ileal mesenteric nerves of BBZDR/Wor rats was substantially less frequent than in BB/Wor- and STZ-rats. These data, considered in the light of the results of previous experiments, argue that hyperglycemia alone is not sufficient to produce sympathetic ganglionic NAD, but rather that it may be the diabetes-induced superimposed loss of trophic support, likely of IGF-I, insulin, or C-peptide, that ultimately causes NAD. Topics: Animals; Autonomic Nervous System Diseases; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Disease Models, Animal; Ganglia, Sympathetic; Hyperglycemia; Ileum; Insulin; Insulin-Like Growth Factor I; Male; Microscopy, Electron; Neuroaxonal Dystrophies; Rats; Rats, Mutant Strains; Sympathetic Fibers, Postganglionic | 2004 |
Low grade inflammation in juvenile obesity and type 1 diabetes associated with early signs of atherosclerosis.
Subclinical inflammation has been implicated in the initiation and/or progression of atherosclerosis. Diabetes mellitus and obesity are risk factors for atherosclerosis, and asymptomatic low grade inflammation occurs prior to overt vascular lesions in these patients. In contrast to adults, little information exists concerning low grade inflammation in young type 1 diabetes and juvenile obesity.. To investigate low grade inflammation and immune activation in juvenile diabetes mellitus and obesity.. hs-CRP, soluble interleukin-2 receptor (sIL-2R), C-peptide, insulin, cortisol, vitamin B12, folic acid, leptin, and homocysteine were determined in 148 patients with juvenile type 1 diabetes, 86 obese children and 142 normal weighted age-matched healthy controls. Intima-media thickness (IMT) and lumen diameter of both common carotid arteries (CCA) was measured by ultrasonography in 52 healthy pediatric controls, 10 diabetics, and 34 obese juveniles.. Serum hs-CRP was significantly elevated in patients with type 1 diabetes (p < 0.0001), and obese children (p < 0.0001) as compared to the control group. The obese juveniles (p < 0.0001) and the diabetics (p < 0.0001) showed significantly increased values for IMT of CAAs. Levels of homocysteine, sIL-2R, insulin, cortisol, vitamin B12, and folic acid did not differ from the controls. The elevation of hs-CRP was more pronounced in obesity as compared to type 1 diabetes (p < 0.0001), and the hs-CRP values correlated significantly with body mass index standard deviation score (BMI-SDS) values. Furthermore, the IMT and the luminal diameter of CCAs showed significant correlations with BMI-SDS values.. A low grade inflammation as determined by serum hs-CRP is significantly increased in children with type 1 diabetes, and even more pronounced in apparently healthy juveniles with obesity. The increased IMT of CCAs strongly argues for an association between this low grade inflammation and early atherosclerotic vessel injury. Topics: Adolescent; Arteriosclerosis; Body Mass Index; C-Peptide; C-Reactive Protein; Carotid Artery, Common; Child; Diabetes Mellitus, Type 1; Female; Folic Acid; Homocysteine; Humans; Inflammation; Leptin; Male; Obesity; Receptors, Interleukin-2; Tunica Intima; Vitamin B 12 | 2004 |
Distinct diagnostic criteria of fulminant type 1 diabetes based on serum C-peptide response and HbA1c levels at onset.
Diagnostic criteria in fulminant type 1 diabetes, a novel subtype of type 1 diabetes, remain unclear.. We analyzed basal and longitudinal changes of serum C-peptide levels during a 75-g oral glucose tolerance test (OGTT) in 125 consecutively recruited patients with type 1 diabetes including fulminant type 1 diabetes (n = 25) and acute-onset type 1 diabetes (n = 100). Discriminating criteria of fulminant type 1 diabetes were examined using receiver-operating characteristic curve analysis and multiple logistic regression analysis.. The integrated values of serum C-peptide response during OGTT (SigmaC-peptide) in fulminant type 1 diabetes at onset, 1 year, and 2 years after onset were markedly lower than those in acute-onset type 1 diabetes. None of the patients with fulminant type 1 diabetes had improvement of C-peptide response to OGTT. Fasting C-peptide values at onset in fulminant type 1 diabetes were significantly lower than those in acute-onset type 1 diabetes. We established diagnostic criteria of serum C-peptide and HbA(1c) levels at onset that discriminate fulminant type 1 diabetes from acute-onset type 1 diabetes with high sensitivity and specificity: a criterion in which the levels of both the fasting C-peptide is Topics: Adolescent; Adult; Age of Onset; Aged; Biomarkers; Blood Glucose; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Infant; Longitudinal Studies; Male; Middle Aged; Regression Analysis; Time Factors | 2004 |
Pancreatic elastase-1 in stools, a marker of exocrine pancreas function, correlates with both residual beta-cell secretion and metabolic control in type 1 diabetic subjects.
Topics: Adult; Biomarkers; Body Mass Index; C-Peptide; Carrier Proteins; Diabetes Mellitus, Type 1; Energy Intake; Feces; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Pancreas; Pancreatic Elastase; Reference Values; Regression Analysis; Statistics, Nonparametric | 2004 |
The rare HLA-DQA1*03-DQB1*02 haplotype confers susceptibility to type 1 diabetes in whites and is preferentially associated with early clinical disease onset in male subjects.
The heterozygous combination of DQA1*03-DQB1*0302 (DQ8) and DQA1*05-DQB1*0201 (DQ2) confers the highest known HLA-DQ-linked risk for type 1 diabetes, suggesting a role for transcomplementation. The trans-heterodimer encoded by DQA1*03 and DQB1*02 is also rarely observed in cis in whites. Islet antibody-positive diabetic patients (P; n = 2,238) and control subjects (C; n = 2,223) of white descent were genotyped by a HLA-DQA1-DQB1 dot-blot method. The presence of the DQA1*03-DQB1*02 haplotype was observed in 22 patients (1%) versus 6 controls (0.3%) (odds ratio [OR] = 3.7, p = 0.005). It was more prevalent in whites of Northern African descent, but both in European (n = 3,813) and in Northern African whites (n = 648), the DQA1*03-DQB1*02 haplotype tended to be associated with diabetes (respectively, P 0.3% vs. C 0.03%, OR = 12.2, p = 0.005; and P 2.1% vs. C 0.6%, OR = 3.8, p = 0.03). DRB1 typing revealed that DQA1*03-DQB1*02 is usually associated with the DRB1*0405 risk allele in European patients and with DRB1*0405, DRB1*07 and DRB1*09 in Northern African whites. Like in DQ2/DQ8-positive patients, the presence of DQA1*03-DQB1*02 is preferentially associated with younger age at clinical onset than in other genotypes, but unlike in subjects carrying DQ2/DQ8, earlier clinical manifestation was mostly restricted to male subjects, often carrying DR3 and/or DQB1*02 on the other chromosome. These results are compatible with an effect of cis-encoded heterodimers or with previously suggested interactions of X-linked genetic factors with (DR3-)DQB1*02 haplotypes. Topics: Adolescent; Adult; Africa, Northern; Age of Onset; Autoantibodies; Belgium; Body Mass Index; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; DNA; Europe; Female; Genetic Predisposition to Disease; Glycated Hemoglobin; Haplotypes; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Infant; Ketones; Male; Phenotype; Polymerase Chain Reaction; Sex Factors; White People | 2004 |
Cross-sectional and prospective association between proinsulin secretion and graft function after clinical islet transplantation.
Proinsulin levels as a marker of beta-cell dysfunction have not been described after clinical islet transplantation. Proinsulin secretion was studied in 23 type 1 diabetic patients after islet allotransplantation and in 20 age-matched nondiabetic controls. Fasting serum insulin, total proinsulin (TP), intact proinsulin, proinsulin fragments (PFs) and their ratios to insulin were determined 1 and 12 months after patients became insulin independent. TP, PF, and proinsulin/insulin ratios were lower in transplant recipients compared with controls, in patients who retained long-term insulin independence. Insulin, C-peptide, and intact proinsulin values were similar in transplant recipients and controls. Hormone levels remained stable over time in the group of patients who retained long-term insulin independence, but the TP and PF levels were higher at 12 months compared with 1 month in the group of patients who resumed insulin therapy. TP and PF levels were reduced in transplant recipients compared with controls but increased over time if insulin independence was lost. Topics: Adult; Blood Glucose; Body Mass Index; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Fasting; Graft Survival; Humans; Insulin; Islets of Langerhans Transplantation; Proinsulin; Reference Values; Time Factors | 2004 |
C-peptide prevents nociceptive sensory neuropathy in type 1 diabetes.
We examined the effects of C-peptide replacement on unmyelinated fiber function in the hind paw, sural nerve C-fiber morphometry, sciatic nerve neurotrophins, and the expression of neurotrophic receptors and content of neuropeptides in dorsal root ganglia in type 1 diabetic BB/Wor-rats. C-peptide replacement from onset of diabetes had no effect on hyperglycemia, but it significantly prevented progressive thermal hyperalgesia and prevented C-fiber atrophy, degeneration, and loss. These findings were associated with preventive effects on impaired availability of nerve growth factor and neurotrophin 3 in the sciatic nerve and significant prevention of perturbed expression of insulin, insulin growth factor-1, nerve growth factor, and neurotrophin 3 receptors in dorsal root ganglion cells. These beneficial effects translated into prevention of the decreased content of dorsal root ganglia nociceptive peptides such as substance P and calcitonin gene-related peptide. From these findings we conclude that replacement of insulinomimetic C-peptide prevents abnormalities of neurotrophins, their receptors, and nociceptive neuropeptides in type 1 BB/Wor-rats, resulting in the prevention of C-fiber pathology and nociceptive sensory nerve dysfunction. The data indicate that perturbed insulin/C-peptide action plays an important pathogenetic role in nociceptive sensory neuropathy and that C-peptide replacement may be of benefit in treating painful diabetic neuropathy in insulin-deficient diabetic conditions. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Male; Rats; Rats, Inbred BB | 2004 |
[Factors affecting C-peptide level during the first year of type 1 diabetes in children].
C-peptide level is the most reliable factor evaluating the endogenous insulin secretion in patients with type 1 diabetes.. The aim of the study was to investigate whether the age at onset, gender, presence of autoantibodies and ketoacidosis at diagnosis and insulin requirement, HbA1c levels could be applied to predict the C-peptide levels in the first year of type 1 diabetes in children.. 122 type 1 diabetic children, aged: 2-18 years (average 11.2), 44 female and 78 male were studied. Fasting C-peptide levels were examined by radioimmunoassay at diagnosis, after 10 days and after 1, 2, 3, 6 and 12 months of disease. At diagnosis islet cell antibodies (ICA) were detected by indirect immunofluorescence, antibodies to glutamic acid decarboxylase (GADA) and tyrosine phosphatase antibodies (IA2A) were measured by microradioimmunoprecipitation assay.. Age at onset was positively correlated to C-peptide levels at each evaluated point of the disease (r=0.3-0.46, p<0.0001). One year after diagnosis C-peptide levels decreased in ICA(+) (p<0.04) and GADA(+) (p<0.002) patients but not in ICA(-) or GADA(-) children. There was no significant difference between the IA2A-positive and negative subjects in the C-peptide levels at 12th month of disease. C-peptide level was also related to ketoacidosis at diagnosis, insulin requirement and HbA1c levels during the first year of type 1 diabetes. Logistic regression analysis showed that male, younger age, low pH, higher HbA1c and insulin requirement at onset were associated with decreased C-peptide level at diagnosis (p<0.00002).. Young age, presence of diabetes-related autoantibodies and hyperglycaemia with severe acidosis at the disease onset may be associated with a decreased residual insulin secretion in type 1 diabetes in children. Topics: Adolescent; Age Factors; Age of Onset; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Disease Progression; Female; Fluorescent Antibody Technique, Indirect; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Infant; Insulin; Insulin Antibodies; Male; Poland; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Radioimmunoprecipitation Assay; Time Factors | 2004 |
[Chronic complications in adult patients with newly diagnosed diabetes mellitus in relation to the presence of humoral autoimmune markers against pancreatic islet cells].
Latent autoimmune diabetes in adults (LADA) is subtype of diabetes type 1. It is well know, that 50% patients with new diagnosed diabetes type 2 present late complications. As far we don't know how many patients with new diagnosed diabetes have late complications according to presence of antibodies against islet antigens. The aim of the study was to compare late complications of diabetes: microangiopathy and macroangiopathy in newly diagnosed adult diabetic patients in relation to presence of humoral autoimmune markers.. We evaluated the presence of late complications in group of 41, hospitalized patients base on clinical examination and medical history. Glutaminic acid decarboxylase antibodies (anti-GAD), protein tyrosine phosphatase antibodies (anti-IA-2) and anti-insulin antibodies (IAA) titers were measured by RIA. The C peptide basal and stimulated, HbA1c, glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, urea, creatinine levels and microalbuminuria were evaluated.. The presence of islet cell specific antibodies were shown in 25 subjects. We observed late complications in 13/25 (52%) in group with positive antibodies titers, and in 10/16 (62.5%) in group without antibodies. We diagnosed the nephropathy (16% vs 6.25%), retinopathy (12% vs 0%), polyneuropathy (20% vs 12.5%), hypertension (32% vs 50%), chronic heart disease (8% vs 25%), overweight (32% vs 50%) and hyperlipidemia (12% vs 25%) respectively in subjects with and without antibodies. The concentrations of total cholesterol (185 +/- 47.8 vs 218 +/- 38.7, p < 0.05) and creatinine level (0.8 +/- 0.15 vs 0.95 +/- 24, p < 0.05) were higher in group without antibodies, but fasting glycemia (181 +/- 69.1 vs 132 +/- 32.8, p < 0.05) was higher in the group presenting with autoantibodies. We did not observed the difference between level of glycosylated hemoglobin in the investigated groups.. There is the tendency to higher incidence of microangiopathy in group of patients positive to islet cell antibodies. Conversely the macroangiopathy appears frequently in patients without antibodies. Topics: Adult; Autoantibodies; Biomarkers; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Female; Glutamate Decarboxylase; Humans; Insulin Antibodies; Islets of Langerhans; Male; Middle Aged; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases | 2004 |
Relationship between the prevalence of anti-glutamic acid decarboxylase autoantibodies and duration of type 1 diabetes mellitus in Brazilian patients.
The objective of the present study was to determine whether the duration of disease has any influence on the prevalence of glutamic acid decarboxylase autoantibodies (GADA) in Brazilian patients with type 1 diabetes (T1D) and variable disease duration. We evaluated 83 patients with T1D. All participants were interviewed and blood was obtained for GADA measurement by a commercial radioimmunoassay (RSR Limited, Cardiff, UK). Four groups of patients were established according to disease duration: A) 1-5 years of disease (N = 24), B) 6-10 years of disease (N = 19), C) 11-15 years of disease (N = 25), and D) >15 years of disease (N = 15). GADA prevalence and its titers were determined in each group. GADA was positive in 38 patients (45.8%) and its frequency did not differ between the groups. The prevalence was 11/24 (45.8%), 8/19 (42.1%), 13/25 (52%), and 6/15 (40%) in groups A, B, C, and D, respectively (P = 0.874). Mean GADA titer was 12.54 +/- 11.33 U/ml for the sample as a whole and 11.95 +/- 11.8, 12.85 +/- 12.07, 10.57 +/- 8.35, and 17.45 +/- 16.1 U/ml for groups A, B, C, and D, respectively (P = 0.686). Sex, age at diagnosis or ethnic background had no significant effect on GADA (+) frequency. In conclusion, in this transversal study, duration of disease did not affect significantly the prevalence of GADA or its titers in patients with T1D after one year of diagnosis. This was the first study to report this finding in the Brazilian population. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Body Mass Index; C-Peptide; Child; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Male; Middle Aged | 2004 |
GADA and islet cell antibodies in Romanian children and adolescents with diabetes mellitus.
Childhood type 1 diabetes is defined by autoimmunity and insulinopenia. Etiopathogenic definition based on biochemical characteristics has recently replaced the clinical definition based on insulin requirement for treatment. The aim of this study was to describe biochemical and clinical characteristics of children with clinically diagnosed type 1 diabetes, hospitalized at the "Cristian Serban" Center in Buziaş.. Fasting C peptide, HbA1c, islet cell autoantibodies (ICA) and antibodies against glutamic acid decarboxylase (GADA) were measured in 278 subjects aged (mean +/- SD; range) 15.1 +/- 4.8 (4-28) years, with a disease duration of 2.1 +/- 0.7 (1.1-3.1) years. GADA and ICA positivity was defined by values higher than the 95th percentile in 99 age-matched non-diabetic controls (0.4 units for ICA and 1.4 for GADA).. As many as 66.2% of all patients had positive GADA and 10.1% had positive ICA. While 68.7% had at least one positive antibody, only 7.6% had both antibodies positive. As expected, most of the children (79.9%) had fasting C peptide values in the low range (<0.5 ng/ml), but 3 patients (1.1%) had biochemical signs of insulin resistance (C peptide concentrations >3 ng/ml). Two of the three insulin resistant children had positive GADA and one of them had positive ICA, therefore showing "mixed" features of both type 1 (autoimmunity) and type 2 diabetes (insulin resistance).. Childhood diabetes is now acknowledged to be a complex disorder with heterogeneity in its pathogenesis, clinical course and outcomes. While type 1 diabetes is the most frequent form of diabetes among Caucasian children, measurement of diabetes autoantibodies and C peptide is necessary to better define the types of diabetes in youth. Topics: Adolescent; Adult; Autoantibodies; Biomarkers; C-Peptide; Child; Child Welfare; Child, Preschool; Cholesterol; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Insulin; Male; Romania; Triglycerides | 2004 |
The value of basal C peptide and its relationship with pancreatic autoantibodies in young adults with type 2 diabetes mellitus.
It is well known that sometimes it is difficult to distinguish between type 1 and 2 diabetes mellitus using clinical criteria, in subjects with disease onset relatively early in adult life. The measurement of C peptide level and of immunological markers may represent important additional tools for establishing the correct diagnosis. The aim of the study is to assess the trend of basal C peptide in patients with clinical diagnosis of type 2 diabetes and to relate it to the type of treatment, the body weight and the positivity for pancreatic autoantibodies.. we studied a group of 268 patients with type 2 diabetes, aged between 30 and 50 years, with a diabetes duration of less than 5 years. In all patients, we measured basal C peptide, islet cell autoantibodies and antibodies against glutamic acid decarboxylase, computed the body mass index and recorded the current antidiabetic treatment.. Based on basal C peptide value, diabetic subjects fell under 3 categories: a) low C peptide (<0.58 ng/ml): 7.5%, b) normal C peptide (0.58-2.70 ng/ml): 57.8%, and c) high C peptide (>2.70 ng/ml): 34.7%. Patients with low C peptide were treated more often with insulin, while those in high C peptide group received more often biguanides. A direct correlation between C peptide and body weight was established. Mean C peptide was lower in patients positive for at least one pancreatic autoantibody, compared to those who were negative for antibodies. Low basal C peptide can be considered criterion for transferring the patients, initially diagnosed as type 2 diabetes, in the type 1 diabetes group. Topics: Adult; Autoantibodies; Biguanides; Biomarkers; Body Mass Index; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Obesity; Pancreas; Predictive Value of Tests; Treatment Outcome | 2004 |
Epitope-restricted 65-kilodalton glutamic acid decarboxylase autoantibodies among new-onset Sardinian type 2 diabetes patients define phenotypes of autoimmune diabetes.
The 65-kDa glutamic acid decarboxylase (GAD65) autoantibodies (GAD65Abs), commonly found in type 1 diabetes mellitus (T1DM) patients, are also found at lower frequencies in type 2 diabetes mellitus (T2DM) patients. GAD65Abs in T1DM patients are epitope specific, in contrast to those found in other GAD65Ab-positive individuals, including T2DM patients. Our aim was to assess whether epitope-specific GAD65Abs, or the additional presence of islet antigen 2 (IA-2) autoantibodies, better define T1DM phenotypes among T2DM patients. GAD65 and IA-2 autoantibodies were analyzed in 1436 Sardinian subjects classified with T2DM and in 384 nondiabetic patient controls. Autoantibody binding specificity to the N-terminal, middle (M), and C-terminal (C) portions of the GAD65 molecule was evaluated. Among the T2DM patients, 5.1% had GAD65 (P < 0.001) and 2.4% had IA-2 autoantibodies, compared with 1.3 and 1.6%, respectively, among the controls. GAD65Ab-positive T2DM patients with M+C (epitope-specific) reactivity were found to have the lowest body mass index (P < 0.001), followed by GAD65Ab/IA-2Ab-positive patients (P < 0.01), and non-M+C-reactive (non-epitope-specific) patients (P < 0.02). In GAD65Ab-positive T2DM patients, c-peptide levels were lower in M+C-reactive compared with non-M+C-reactive patients. Sardinian T2DM patients with M+C-predominant GAD65Ab reactivity have clinical features more similar to those of T1DM patients. Thus, GAD65Ab epitope analysis may help to define T1DM phenotypes among newly diagnosed GAD65Ab-positive patients classified with T2DM. Topics: Adult; Aged; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Epitopes; Female; Glutamate Decarboxylase; Humans; Isoenzymes; Male; Middle Aged; Phenotype | 2004 |
Clinical and genetic characteristics of GAD-antibody positive patients initially diagnosed as having type 2 diabetes.
The present study was conducted to clarify the clinical and genetic characteristics of the diabetic patients who have antibodies to glutamic acid decarboxylase (GADab) but are diagnosed initially as type 2 diabetes because of the slow progression. Fifty-five GADab+ patients and 137 GADab- patients were recruited. The GADab+ patients were divided into two subgroups according to their antibody titers. The high-titer subgroup (Ab > or = 20 U/ml) had lower urinary C-peptide concentrations, and was assigned insulin therapy more often than the GADab- patients. In contrast to the high-titer subgroup, clinical parameters in the low-titer subgroup were similar to the GADab- diabetic patients. The urinary C-peptide levels correlated negatively with the GADab titer in the GADab+ patients. Analysis of type 1 diabetes-susceptible HLA alleles revealed high frequencies of the B54 and DRB1*0405 allele, but not the B61 and DRB1*0901 alleles, in the high-titer subgroup, whereas the frequency of the protective DRB1*1502 allele was decreased. The GADab+ patients with the B54 allele had higher GADab titers and lower urinary C-peptide excretion than patients without this allele. These data indicated that patients with a high-GADab titer share the autoimmune background characteristic of type 1 diabetes. Topics: Adult; Alleles; Autoantibodies; Autoimmunity; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Glutamate Decarboxylase; HLA Antigens; Humans; Male; Middle Aged | 2004 |
A Korean patient with fulminant autoantibody-negative type 1 diabetes.
Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Humans; Korea; Male | 2004 |
IgG4-subclass of glutamic acid decarboxylase antibody is more frequent in latent autoimmune diabetes in adults than in type 1 diabetes.
Glutamic acid decarboxylase autoantibodies (GADA) are the most frequent beta-cell-specific autoantibodies in type 1 diabetes and in latent autoimmune diabetes in adults (LADA). The autoimmune attack on pancreatic islet cells is associated with a T helper 1 cell (T(h)1) response, mainly represented by IgG(1)-subclass in humans. It has been proposed that the presence of IgG(4) may be associated with a T(h)2 response. The aim of our study was to compare the GADA IgG-subclass distribution between adult patients with type 1 diabetes and LADA.. Patients with type 1 diabetes (n=45) and patients with LADA (n=60) were included. Radioimmunoprecipitation assay with IgG-subclass specific Sepharose (IgG(1), IgG(2), IgG(3) and IgG(4)) was used to precipitate the antibody/antigen-complex.. We only detected IgG(4)-subclass of GADA in subjects with LADA (26.7%; p<0.001). IgG(1) was the most common GADA-subclass in both groups, however IgG(1) as the solely expressed subclass was more common among type 1 diabetic patients (77.8%; p<0.05). The rank order of the frequencies of IgG-subclasses in type 1 diabetes was IgG(1)>IgG(3)>IgG(2)>IgG(4) and in LADA patients IgG(1)>IgG(4)>IgG(2)>IgG(3).. The difference in GADA IgG-subclasses could indicate a different immune response, possibly an altered balance between T(h)1 and T(h)2 cytokine profile in pancreatic islets. This difference could contribute to the slower rate of beta cell destruction in LADA patients, as reflected by a higher C-peptide level at clinical onset. Topics: Adolescent; Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Immunoglobulin G; Middle Aged | 2004 |
Latent autoimmune diabetes mellitus in children (LADC) with autoimmune thyroiditis and Celiac disease.
Latent autoimmune diabetes mellitus in adults (LADA) is characterized by clinical presentation as type 2 diabetes mellitus after 25 years of age, initial control achieved with oral hypoglycemic agents for at least 6 months, presence of autoantibodies and some immunogenetic features of type 1 diabetes mellitus. An 8.3 year-old girl was referred to our pediatric endocrinology department because of incidental glucosuria. She did not complain of polyuria, polydipsia, or weight loss. Her body mass index (BMI) was at the 80th percentile. Fasting glucose was 126 mg/dl, and OGTT glucose level at 120 min was 307 mg/dl. Although C-peptide levels were normal, her first phase insulin response (FIR) was lower than the 1st percentile. Anti-insulin antibody (AIA), islet cell antibody (ICA), and anti-glutamic acid decarboxylase (antiGAD) were negative. According to the clinical and laboratory findings, she was diagnosed as having type 2 diabetes mellitus. She was started with oral anti-diabetic treatment for a period of 1 year. Insulin had to be initiated for worsening of HbA1c levels. In the fourth year of follow-up, she was admitted to our hospital with diabetic ketoacidosis although she was on an intensive insulin regimen. At this time, C-peptide levels were low, antiGAD and AIA were positive with HLA DR3/DQ2 haplotype. In addition, her thyroid peroxidase antibody and endomysium antibody were found to be high at follow-up. Small intestinal biopsy revealed celiac disease. This patient may represent the first case of latent autoimmune diabetes mellitus in children (LADC) with autoimmune thyroiditis and celiac disease. Topics: Blood Glucose; Body Mass Index; C-Peptide; Celiac Disease; Child; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Hypoglycemic Agents; Insulin; Thyroiditis, Autoimmune | 2004 |
Residual beta-cell function more than glycemic control determines abnormalities of the insulin-like growth factor system in type 1 diabetes.
The GH-IGF-I axis is disturbed in patients with type 1 diabetes. Our aim was to investigate whether abnormalities are found in patients in very good glycemic control and, if so, to estimate the role of residual beta-cell function. Patients with hemoglobin A1c (HbA1c) less than 6% (reference range, 3.6-5.4%) were selected for the study. Twenty-two men and 24 women, aged 41.3 +/- 13.8 yr (mean +/- SD), with a diabetes duration of 17.8 +/- 14.6 yr participated. Healthy controls (15 women and nine men), aged 41.3 +/- 13.0 yr, were also studied. Overnight fasting serum samples were analyzed for HbA1c, C peptide, free and total IGFs, IGF-binding proteins (IGFBPs), GH-binding protein, and IGFBP-3 proteolysis. HbA1c was 5.6 +/- 0.5% in patients and 4.4 +/- 0.3% in controls. Total IGF-I was 148 +/- 7 microg/liter in patients and 178 +/- 9 microg/liter in controls (P < 0.001). Free IGF-I, total IGF-II, IGFBP-3, and GH-binding protein were lower, whereas IGFBP-1, IGFBP-1-bound IGF-I, and IGFBP-2 were elevated compared with control values. Patients with detectable C peptide (> or =100 pmol/liter) had higher levels of total IGF-I, free IGF-I, and total IGF-II and lower levels of IGFBP-1 and IGFBP-2 than those with an undetectable C peptide level despite having identical average HbA1c. IGFBP-3 proteolysis did not differ between patients and controls. Despite very good glycemic control, patients with type 1 diabetes and no endogenous insulin production have low free and total IGF-I. Residual beta-cell function, therefore, seems more important for the disturbances in the IGF system than good metabolic control per se, suggesting that portal insulin delivery is needed to normalize the IGF system. Topics: Adult; Aging; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin-Like Growth Factor Binding Proteins; Insulin-Like Growth Factor I; Insulin-Like Growth Factor II; Islets of Langerhans; Male; Middle Aged; Somatomedins | 2004 |
Selection of diabetic patients for islet transplantation. A single-center experience.
Since the Edmonton protocol, islet transplantation (IT) offers the prospect of adequate glycemic control with no major surgical risk. In our single-center experience of IT, we studied the recruitment of eligible diabetic patients.. Between 1998 and 2002, we screened 79 diabetic patients that were divided into 2 groups according to their renal status: 41 were not receiving dialysis (ND) while 38 were receiving ongoing dialysis (D).. In the ND group, 20 patients initiated the contact with our team, 8 patients were recruited during hospitalization for very poor glycemic imbalance, and 13 were referred by their diabetologist. 14/41 (34%) patients were ineligible for IT either because of very good glycemic balance, detectable C-peptide (C-p), kidney or liver problems, or plans for future pregnancy. 16/41 (39%) did not wish to proceed, 7 of whom were more interested by a pump. 11/41 (27%) were eligible, among which 8 are currently being assessed, 1 is on the waiting list and 2 have been transplanted. In the D group, 17/38 (45%) had a detectable C-p and received a kidney graft alone. Among the remaining 21 C-p negative diabetic patients, 3 were not eligible for kidney transplantation mainly for psychological reasons, and 4 were enlisted for kidney+pancreas transplantation. The remaining 14 C-p negative patients were kidney-transplanted. Among them, 6 were not eligible for IT, mainly for lack of motivation, slightly positive C-p stimulation tests, obesity, cancer, or increased creatininemia. The remaining 8/14 C-p negative kidney-engrafted patients were enlisted for IT. 3 had secondary failure with the pre-Edmonton immunosuppressive (IS) protocol. Five have been transplanted with the Edmonton-like IS regimen.. Twenty-five per cent of the 79 patients for whom islet transplantation was considered underwent pregraft assessment and 12% (10 patients, 8 kidney-transplanted and 2 islet alone) of the 79 have been transplanted. The main eligibility criteria were undetectable Cpeptide, normal kidney function, average weight, glycemic imbalance, hypoglycemia unawareness, and glycemic brittleness. Topics: Adult; Biomarkers; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Male; Middle Aged; Patient Selection; Renal Replacement Therapy; Retrospective Studies; Treatment Outcome | 2004 |
Optimal cutoff point of glutamate decarboxylase antibody titers in differentiating two subtypes of adult-onset latent autoimmune diabetes.
The optimal cutoff point of glutamate decarboxylase antibody (GAD-Ab) titers for differentiating two latent autoimmune diabetes (LADA) subtypes remains unclear. One hundred and forty-five GAD-Ab-positive patients screened from phenotypic type 2 diabetes were diagnosed as LADA. The clinical features were compared among LADA patients with different GAD-Ab titers. The receiver-operating characteristic (ROC) curve was used to evaluate the diagnostic value of GAD-Ab titers and to define the optimal cutoff point. The heterogeneity of clinical features in LADA could be discriminated by five GAD-Ab titers, with maximal differences at the titer of 175 U/mL. The ROC curve analysis showed that the optimal cutoff point for discriminating two LADA subtypes was at the titer of 175 U/mL, with sensitivity and specificity of 54.5% and 92.1%, respectively. These findings demonstrated that the two clinically distinct subtypes of LADA can be optimally discriminated by the GAD-Ab titers. Topics: Adult; Antibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glutamate Decarboxylase; Humans; Male; Middle Aged; Radioimmunoassay; ROC Curve; Sensitivity and Specificity | 2004 |
Association between CTLA-4 +49 A/G polymorphism and type 1B diabetes in Japanese population.
+49 A/G polymorphism of CTLA-4 gene has been suggested to be associated with type 1 diabetes in some populations. However, a functional significance of the +49 A/G polymorphism is unknown, because it is believed the polymorphism does not affect the function of the CTLA-4 molecule. In this study, we examined the +49 A/G polymorphism of the CTLA-4 gene in 30 Japanese type 1 diabetic patients (14 type 1B and 16 type 1A) and 40 non-diabetic subjects in a case-control study, and stratified patients according to genotype of the polymorphism. The distribution of genotype frequencies differed between type 1 diabetic patients and controls (p<0.01). When the subjects were subdivided into type 1A and type 1B subgroups, a significant difference in G allele frequency was found only between type 1B patients and controls, whereas G allele frequency tended to be higher in type 1A diabetic patients than controls. Type 1B patients displayed more severe metabolic decompensation (higher plasma glucose concentration, lower urinary C-peptide levels, higher insulin requirement, and higher serum amylase levels), and were found to be more prone to diabetic ketoacidosis than type 1A patients. After stratification by genotype, differences in urinary C-peptide and serum amylase levels between type 1A and type 1B patients were found to be due to differences in the GG genotype subgroup, whereas in the AG subgroup those differences disappeared. In conclusion, the +49 A/G polymorphism of CTLA-4 gene was associated with the occurrence of type 1B diabetes in a Japanese population, and type 1B diabetics with a GG genotype were associated with more severe cell dysfunction than their type 1A counterparts. Topics: Adult; Alleles; Amylases; Antigens, CD; Antigens, Differentiation; Autoantibodies; Blood Glucose; C-Peptide; CTLA-4 Antigen; Diabetes Mellitus, Type 1; DNA; Female; Genotype; Humans; Japan; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Single Nucleotide | 2004 |
[Biological differences on onset among type 1A diabetics in relation to HLA-DQ genetic markers].
The hypothesis that diabetes mellitus presentation partially depends on the genetic characteristics of the patient has been proposed. Up to date this kind of studies have been made by serology, so there are no data about the role played by DQ haplotypes in the presentation and clinical importance of DM1. This fact is analysed in the present study.. We studied DQ haplotypes (molecular biology) in 86 patients affected by DM1. Their relationship with several parameters found on illness debut, such as age, sex, C peptid and clinical importance are analysed.. 89% of the patients showed a DQ that increases the risk of diabetes. Average age on onset was 16 years and the median age 9 years. No differences in relation to sex were observed. DQA1*0501, 0301/DQB1*0201, 0302 heterocygotes show an earlier onset (9 years, opposite to 17 in the rest) and the youngest (smaller than 16 years) they have to the onset a smaller pancreatic reservation (peptid C of 0.37 ng/dl in front of 1.4 of those bigger than this age).. DQA1*0501, 0301/DQB1*0201 heterocygocity increases the probability of an earlier and more aggressive debut of the illness, being related this characteristic younger debut to a smaller pancreatic reservation. Topics: Adolescent; Adult; Age of Onset; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Gene Frequency; Genetic Markers; Genetic Predisposition to Disease; Genetic Testing; Haplotypes; HLA-DQ Antigens; Humans; Male; Middle Aged | 2003 |
Effects of free fatty acids per se on glucose production, gluconeogenesis, and glycogenolysis.
Insulin-independent effects of a physiological increase in free fatty acid (FFA) levels on fasting glucose production, gluconeogenesis, and glycogenolysis were assessed by administering [6,6-(2)H(2)]-glucose and deuteriated water ((2)H(2)O) in 12 type 1 diabetic patients, during 6-h infusions of either saline or a lipid emulsion. Insulin was either fully replaced (euglycemic group, n = 6), or underreplaced (hyperglycemic group, n = 6). During saline infusions, plasma FFA levels remained unchanged. Glucose concentrations decreased from 6.7 +/- 0.4 to 5.3 +/- 0.4 mmol/l and 11.9 +/- 1.0 to 10.5 +/- 1.0 mmol/l in the euglycemic and hyperglycemic group, respectively. Accordingly, glucose production declined from 84 +/- 5 to 63 +/- 5 mg x m(-2) x min(-1) and from 84 +/- 5 to 68 +/- 4 mg x m(-2) x min(-1), due to declining rates of glycogenolysis but unaltered rates of gluconeogenesis. During lipid infusions, plasma FFA levels increased twofold. In the euglycemic group, plasma glucose increased from 6.8 +/- 0.3 to 7.8 +/- 0.8 mmol/l. Glucose production declined less in the lipid study than in the saline study due to a stimulation of gluconeogenesis by 6 +/- 1 mg x m(-2) x min(-1) and a decline in glycogenolysis that was 6 +/- 2 mg x m(-2) x min(-1) less in the lipid study than in the saline study. In contrast, in the hyperglycemic group, there were no significant effects of elevated FFA on glucose production, gluconeogenesis, or glycogenolysis. In conclusion, a physiological elevation of plasma FFA levels stimulates glycogenolysis as well as gluconeogenesis and causes mild fasting hyperglycemia. These effects of FFA appear attenuated in the presence of hyperglycemia. Topics: Adult; Blood Glucose; C-Peptide; Deuterium Oxide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Gluconeogenesis; Glucose Clamp Technique; Glycogen; Humans; Hyperglycemia; Insulin; Kinetics; Male; Reference Values | 2003 |
Similar genetic features and different islet cell autoantibody pattern of latent autoimmune diabetes in adults (LADA) compared with adult-onset type 1 diabetes with rapid progression.
To compare the clinical parameters, C-peptide levels, pattern of islet cell-specific autoantibodies, and prevalence of predisposing genotypes in subjects with latent autoimmune diabetes in adults (LADA) and those with adult-onset type 1 diabetes with rapid progression.. We evaluated the clinical parameters, C-peptide levels, and islet cell-specific autoantibodies in 54 LADA, 57 adult-onset type 1 diabetic, and 190 type 2 diabetic patients. Islet cell autoantibodies were also compared between subgroups of newly diagnosed patients with LADA and those with newly diagnosed adult-onset and childhood-onset type 1 diabetes. The genetic study was performed in subjects with LADA and those with adult-onset type 1 diabetes in comparison with a control population.. There were no differences in the clinical parameters between LADA and adult-onset type 1 diabetes. Patients with LADA had lower BMI (P < 0.0001), waist-to-hip ratio (0.0029), total cholesterol (P = 0.001), and triglycerides (P = 0.001); higher HDL cholesterol levels (P < 0.0001); and lower prevalence of hypertension (P = 0.0028) compared with patients with type 2 diabetes. C-peptide levels were similar at onset (P = 0.403) but decreased less rapidly in LADA than in adult-onset type 1 diabetes (P = 0.0253). Single-autoantibody positivity was more often seen in LADA than in type 1 diabetes (P = 0.0001). The prevalence of predisposing HLA-DQB1*0302, -DR4, -DR3, and -DR3/DR4 genotypes and the DR4-DQB1*0302 haplotype were increased in both LADA and adult-onset type 1 diabetic subjects compared with the control population. There were no differences in the frequencies of these risk alleles and haplotypes between the two patient groups.. Subjects with LADA had clinical characteristics similar to those with adult-onset type 1 diabetes with rapid progression. C-peptide levels did not differ at onset but decreased less rapidly in LADA. Patients with LADA rather had single islet cell-specific autoantibody positivity. The prevalence of HLA-DQB1*0302, -DR4, -DR3, and -DR3/DR4 risk alleles and the DR4-DQB1*0302 high-risk haplotype did not differ in the two forms of autoimmune diabetes. Topics: Adult; Aged; Alleles; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Male; Middle Aged | 2003 |
Retransplantation of islets after simultaneous islet-kidney transplantation: a case report.
Topics: Adult; Blood Glucose; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Dose-Response Relationship, Drug; Histocompatibility Testing; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Reoperation; Treatment Outcome | 2003 |
[Glutamic acid decarboxylase and tyrosine phosphatase-like IA-2 antibodies for diabetes classification in unselected diabetic patients].
The determination of glutamic acid decarboxylase and tyrosine phosphatase-like antibodies (GAD-AB and IA-2-AB) may be useful for the classification of diabetes, and in selected patient groups the measurement of these autoantibodies has been shown to be rather sensitive and specific.. In this study we examined the use of these antibody determination in a clinical setting of 157 diabetic outpatients recruited randomly from our diabetes clinic. The prevalence of the different antibodies was set in relation to the clinically classified diabetes type and to diabetes duration.. Among the patients with a clinical diagnosis of type 1 diabetes, the GAD-AB were clearly positive in 44% and borderline positive in 10%, whereas the IA-2-AB were positive or borderline positive in 36% of these patients. The prevalence of positive autoantibodies declined with increasing duration of type 1 diabetes. Among the patients with clinically diagnosed type 2 diabetes, the GAD-AB were clearly positive in 25.2% and borderline positive in 13.1%, IA-2-AB were only found in 4.7%. Patients with a clinical diagnosis of type 2 diabetes but positive for GAD-AB could not clearly be identified as having latent autoimmune diabetes in adults (LADA), since some of them did not need insulin therapy up to 10 years after the diagnosis of diabetes. The prevalence of GAD-AB in type 2 diabetic/LADA patients did not depend on diabetes duration.. We conclude that the determination especially of GAD-AB may be useful for the classification of diabetes in clinically unclear cases. The additional determination of IA-2-AB appears to provide only limited additional information. Topics: Adult; Autoantibodies; C-Peptide; Data Interpretation, Statistical; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Male; Middle Aged; Patient Selection; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Regression Analysis; Sensitivity and Specificity; Time Factors | 2003 |
[Clinical, metabolic, immunologic and genotypic characteristics in non-pediatric patients with type 1A diabetes mellitus. Onset and short-term prognosis].
Around 50% of new cases of type 1 diabetes mellitus (DM1) are seen in subjects aged above 15 years. It is of particular interest the characterization of such a population.. a) to characterize a group of non-pediatric subjects with DM1 at the onset of the disease; b) to evaluate the prognosis of the disease under conventional intensive insulin therapy, and c) to investigate the presence of mutations in the HNF-1* gene in those subjects who did not display pancreatic autoimmune markers.. All subjects with an age >= 15 and 35 years recently diagnosed DM1 (1998-2001) were included in the study. Pancreatic cell function was assessed by glucagon test (at onset and at 12 months). The presence of pancreatic autoantibodies, GAD, IA2 and IAA was evaluated. HLA class II genes and the 10 exons of HNF-1* gene were analyzed from genomic DNA.. We studied 86 subjects (32 women, 23.9 [5.3] year-old). Eighty percent of subjects were positive for any of the studied autoantibodies. Alone or in combination, GAD was positive in 68.6% of subjects, IA2 in 45.3% and IAA in 27.9% of them. Most frequent haplotype was DRB1*0301-DQA1*0501-DQB*0201. There were no differences with regard to clinical, metabolic or genetic characteristics among those subjects with or without presence of pancreatic autoantibodies (at onset and at 12 months). We did not find mutations in the HNF-1* gene in any of the subjects included in our study. After 12 months of follow-up, cell function remained unaltered in comparison with that observed at the onset of the disease.. Clinical, immunological and HLA characteristics of a non-pediatric DM1 population are in agreement with expected results. The absence of pancreatic autoimmune markers neither rules out the existence of type 1A diabetes mellitus nor is associated with mutations in the MODY-3 gene. A therapeutic programme using conventional intensified insulin treatment prevents the impairment of insulin secretory capacity for a short-term follow-up. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; DNA-Binding Proteins; Female; Glycated Hemoglobin; Haplotypes; Hepatocyte Nuclear Factor 1; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 1-beta; Histocompatibility Antigens Class II; Humans; Insulin Antibodies; Male; Nuclear Proteins; Prognosis; Transcription Factors | 2003 |
Beta-cell function and the development of diabetes-related complications in the diabetes control and complications trial.
In patients with type 1 diabetes, measurement of connecting peptide (C-peptide), cosecreted with insulin from the islets of Langerhans, permits estimation of remaining beta-cell secretion of insulin. In this retrospective analysis to distinguish the incremental benefits of residual beta-cell activity in type 1 diabetes, stimulated (90 min following ingestion of a mixed meal) C-peptide levels at entry in the Diabetes Control and Complications Trial (DCCT) were related to measures of diabetic retinopathy and nephropathy and to incidents of severe hypoglycemia. Based on the analytical sensitivity of the assay (0.03 nmol/l) and study entry criteria, the DCCT subjects were divided into four groups of stimulated C-peptide responses: Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Hypoglycemia; Islets of Langerhans; Male; Retrospective Studies | 2003 |
Evaluation of the new ADA and WHO criteria for classification of diabetes mellitus in young adult people (15-34 yrs) in the Diabetes Incidence Study in Sweden (DISS).
We aimed to evaluate how an aetiology-based classification, as recommended in the ADA and WHO guidelines for classification of diabetes mellitus, matches clinical judgement in the Diabetes Incidence Study in Sweden (DISS), a study covering incident cases of diabetic patients aged 15 to 34 years.. During a 1-year period (1998), blood samples were taken at diagnosis and 4 months (median) thereafter. Patients were classified according to clinical judgement by the reporting physicians and assessments of islet antibodies (ICA, GADA, and IA-2A) and plasma C-peptide.. In 1998, 422 patients were registered in DISS. Among the 313 patients participating in the follow-up, most with clinical Type 1 diabetes (185/218, 85%, 95% CI 79-89%) were islet antibody positive (ab+) at diagnosis. In addition, 14 out of 58 (24%, 14-37%) with clinical Type 2 diabetes and 21 out of 37 (57%, 40-73%) with unclassifiable diabetes were antibody positive at diagnosis. Further to this, 4 out of 33 (12%, 3-28%) were antibody negative with clinical Type 1 diabetes and 4 out of 44 (9%, 3-22%) with Type 2 had converted to antibody positive at follow-up. Among those who were constantly antibody negative, 10 out of 29 (34%, 18-54%) with clinical Type 1 and 1 out of 16 (6%, 0-30%) with unclassifiable diabetes had fasting plasma C-peptide concentrations below the normal range (<0.25 nmol/l) at follow-up.. Most young adults with clinical Type 1 diabetes (199/218, 91%) had objective Type 1 (ab+ at diagnosis/follow-up and/or low fasting plasma C-peptide concentrations at follow-up), as did one third (18/58, 31%) with clinical Type 2 diabetes and more than half (22/37, 59%) with unclassifiable diabetes. About 10% of those who were antibody negative converted to antibody positive. Our study underlines that a classification considering aetiology is superior to clinical judgement. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Humans; Incidence; Islets of Langerhans; Societies, Medical; Sweden; United States; World Health Organization | 2003 |
Prediction of severe hypoglycaemia by angiotensin-converting enzyme activity and genotype in type 1 diabetes.
We have previously shown a strong relationship between high angiotensin-converting enzyme (ACE) activity, presence of the deletion (D) allele of the ACEgene and recall of severe hypoglycaemic events in patients with Type 1 diabetes. This study was carried out to assess this relationship prospectively.. We followed 171 adult outpatients with Type 1 diabetes in a one-year observational study with the recording of severe hypoglycaemia. Participants were characterised by serum ACE activity and ACE genotype and not treated with ACE inhibitors or angiotensin II receptor antagonists.. There was a positive relationship between serum ACE activity and rate of severe hypoglycaemia with a 2.7 times higher rate in the fourth quartile of ACE activity compared to the first quartile (p=0.0007). A similar relationship was observed for the subset of episodes with coma (2.9 times higher rate in fourth quartile compared to first quartile; p=0.048). The impact of serum ACE activity was most pronounced in C-peptide negative subjects (4.2 times higher rate in fourth quartile compared to first quartile; p=0.003), and in this subgroup carriers of the D allele of the ACEgene had higher rates of severe hypoglycaemia compared to the group homozygous for the insertion (I) allele. In a multiple regression analysis high serum ACE activity and impaired awareness of hypoglycaemia were identified as the only significant predictors of severe hypoglycemia.. High ACE activity and the presence of the D allele of the ACE gene predict a high rate of severe hypoglycaemia in Type 1 diabetes. Topics: Adult; Alleles; Awareness; C-Peptide; Diabetes Mellitus, Type 1; Female; Genotype; Humans; Hypoglycemia; Male; Middle Aged; Multivariate Analysis; Peptidyl-Dipeptidase A; Prognosis; Retrospective Studies; Risk Factors; Severity of Illness Index | 2003 |
Long-term beneficial effect of islet transplantation on diabetic macro-/microangiopathy in type 1 diabetic kidney-transplanted patients.
Our aim was to evaluate the long-term effects of transplanted islets on diabetic macro-/microangiopathy in type 1 diabetic kidney-transplanted patients.. A total of 34 type 1 diabetic kidney-transplanted patients underwent islet transplantation and were divided into two groups: successful islet-kidney transplantation (SI-K; 21 patients, fasting C-peptide serum concentration >0.5 ng/ml for >1 year) and unsuccessful islet-kidney transplantation (UI-K; 13 patients, fasting C-peptide serum concentration <0.5 ng/ml). Patients cumulative survival, cardiovascular death rate, and atherosclerosis progression were compared in the two groups. Skin biopsies, endothelial dependent dilation (EDD), nitric oxide (NO) levels, and atherothrombotic risk factors [von Willebrand factor (vWF) and D-dimer fragment (DDF)] were studied cross-sectionally.. The SI-K group showed a significant better patient survival rate (SI-K 100, 100, and 90% vs. UI-K 84, 74, and 51% at 1, 4, and 7 years, respectively, P = 0.04), lower cardiovascular death rate (SI-K 1/21 vs. UI-K 4/13, chi(2) = 3.9, P = 0.04), and lower intima-media thickness progression than the UI-K group (SI-K group: delta1-3 years -13 +/- 30 micro m vs. UI-K group: delta1-3 years 245 +/- 20 micro m, P = 0.03) with decreased signs of endothelial injuring at skin biopsy. Furthermore, the SI-K group showed a higher EDD than the UI-K group (EDD: SI-K 7.8 +/- 4.5% vs. UI-K 0.5 +/- 2.7%, P = 0.02), higher basal NO (SI-K 42.9 +/- 6.5 vs. UI-K 20.2 +/- 6.8 micro mol/l, P = 0.02), and lower levels of vWF (SI-K 138.6 +/- 15.3 vs. UI-K 180.6 +/- 7.0%, P = 0.02) and DDF (SI-K 0.61 +/- 0.22 vs. UI-K 3.07 +/- 0.68 micro g/ml, P < 0.01). C-peptide-to-creatinine ratio correlated positively with EDD and NO and negatively with vWF and DDF.. Successful islet transplantation improves survival, cardiovascular, and endothelial function in type 1 diabetic kidney-transplanted patients. Topics: Adult; C-Peptide; Cardiovascular Diseases; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Female; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Survival Rate; Time Factors; Treatment Failure; Treatment Outcome | 2003 |
Accuracy of an electrochemical sensor for measuring capillary blood ketones by fingerstick samples during metabolic deterioration after continuous subcutaneous insulin infusion interruption in type 1 diabetic patients.
This study was designed to test the accuracy of capillary ketonemia for diagnosis of ketosis after interruption of insulin infusion.. A total of 18 patients with type 1 diabetes treated by external pump were studied during pump stop for 5 h. Plasma and capillary ketonemia and ketonuria were determined every hour from 7:00 A.M. (time 0 min = T0) to 12:00 P.M. (time 300 min = T300). Plasma beta-hydroxybutyrate (beta-OHB) levels were measured by an enzymatic end point spectrophotometric method, and capillary beta-OHB levels were measured by an electrochemical method (MediSense Optium meter). Ketonuria was measured by a semiquantitative test (Ketodiastix). Positive ketosis was defined by a value of >/=0.5 mmol/l for ketonemia and >/=4 mmol/l (moderate) for ketonuria.. After stopping the pump, concentrations of beta-OHB in both plasma and capillary blood increased significantly at time 60 min (T60) compared with T0 (P < 0.001), reaching maximum levels at T300 (1.30 +/- 0.49 and 1.23 +/- 0.78 mmol/l, respectively). Plasma and capillary beta-OHB values were highly correlated (r = 0.94, P < 0.0001). For diagnosis of ketosis, capillary ketonemia has a higher sensitivity and negative predictive value (80.4 and 82.5%, respectively) than ketonuria (63 and 71.8%, respectively). For plasma glucose levels >/=250 mg/dl, plasma and capillary ketonemia were found to be more frequently positive (85 and 78%, respectively) than ketonuria (59%) (P = 0.017). The time delay to diagnosis of ketosis was significantly higher for ketonuria than for plasma ketonemia (212 +/- 67 vs. 140 +/- 54 min, P = 0.0023), whereas no difference was noted between plasma and capillary ketonemia.. The frequency of screening for ketosis and the efficiency of detection of ketosis definitely may be improved by the use of capillary blood ketone determination in clinical practice. Topics: 3-Hydroxybutyric Acid; Adult; Age of Onset; Blood Glucose; Blood Specimen Collection; C-Peptide; Capillaries; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Electrochemistry; Fingers; Humans; Insulin Infusion Systems; Ketone Bodies; Normal Distribution; Reagent Strips; Sensitivity and Specificity | 2003 |
Laparoscopic approach for human islet transplantation into a defined liver segment in type-1 diabetic patients.
Intra-portal islet transplantation is usually performed by cannulation of a mesenteric vein during laparotomy or through percutaneous trans-hepatic cannulation of a portal branch. In this study, we describe a new laparoscopic technique for intra-portal islet transplantation in a defined liver segment, as an alternative to the current procedures. Eighteen type-1 diabetic patients underwent laparoscopic re-permeabilisation of the umbilical vein, followed by catheterization of the left branch of the portal vein. The catheter was guided under fluoroscopic control into a chosen liver segment. It was then secured to the skin or connected to an implantable venous access device. Thereafter, the islet preparation was slowly injected. There was no rise in portal pressure. The median duration of the procedure was 85 min. The procedure was successful in 17 of 18 cases. There were no surgical complications. We conclude that this laparoscopic procedure is a feasible, convenient, and safe alternative method of islet transplantation. Moreover, it allows multiple deliveries of islets into the same liver segment. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Graft Survival; Humans; Islets of Langerhans Transplantation; Laparoscopy; Liver; Male; Middle Aged; Portal System; Transplantation, Heterologous; Treatment Outcome | 2003 |
Sleep-related hypoglycemia-associated autonomic failure in type 1 diabetes: reduced awakening from sleep during hypoglycemia.
Given that iatrogenic hypoglycemia often occurs during the night in people with type 1 diabetes, we tested the hypothesis that physiological, and the resulting behavioral, defenses against developing hypoglycemia-already compromised by absent glucagon and attenuated epinephrine and neurogenic symptom responses-are further compromised during sleep in type 1 diabetes. To do so, we studied eight adult patients with uncomplicated type 1 diabetes and eight matched nondiabetic control subjects with hyperinsulinemic stepped hypoglycemic clamps (glucose steps of approximately 85, 75, 65, 55, and 45 mg/dl) in the morning (0730-1230) while awake and at night (2100-0200) while awake throughout and while asleep from 0000 to 0200 in random sequence. Plasma epinephrine (P = 0.0010), perhaps norepinephrine (P = 0.0838), and pancreatic polypeptide (P = 0.0034) responses to hypoglycemia were reduced during sleep in diabetic subjects (the final awake versus asleep values were 240 +/- 86 and 85 +/- 47, 205 +/- 24 and 148 +/- 17, and 197 +/- 45 and 118 +/- 31 pg/ml, respectively), but not in the control subjects. The diabetic subjects exhibited markedly reduced awakening from sleep during hypoglycemia. Sleep efficiency (percent time asleep) was 77 +/- 18% in the diabetic subjects, but only 26 +/- 8% (P = 0.0109) in the control subjects late in the 45-mg/dl hypoglycemic steps. We conclude that autonomic responses to hypoglycemia are reduced during sleep in type 1 diabetes, and that, probably because of their reduced sympathoadrenal responses, patients with type 1 diabetes are substantially less likely to be awakened by hypoglycemia. Thus both physiological and behavioral defenses are further compromised during sleep. This sleep-related hypoglycemia-associated autonomic failure, in the context of imperfect insulin replacement, likely explains the high frequency of nocturnal hypoglycemia in type 1 diabetes. Topics: Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Humans; Hypoglycemia; Insulin; Reference Values; Sleep; Sleep Stages; Sleep, REM; Wakefulness | 2003 |
Reversal of hyperglycemia in mice by using human expandable insulin-producing cells differentiated from fetal liver progenitor cells.
Beta-cell replacement is considered to be the most promising approach for treatment of type 1 diabetes. Its application on a large scale is hindered by a shortage of cells for transplantation. Activation of insulin expression, storage, and regulated secretion in stem/progenitor cells offers novel ways to overcome this shortage. We explored whether fetal human progenitor liver cells (FH) could be induced to differentiate into insulin-producing cells after expression of the pancreatic duodenal homeobox 1 (Pdx1) gene, which is a key regulator of pancreatic development and insulin expression in beta cells. FH cells possess a considerable replication capacity, and this was further extended by introduction of the gene for the catalytic subunit of human telomerase. Immortalized FH cells expressing Pdx1 activated multiple beta-cell genes, produced and stored considerable amounts of insulin, and released insulin in a regulated manner in response to glucose. When transplanted into hyperglycemic immunodeficient mice, the cells restored and maintained euglycemia for prolonged periods. Quantitation of human C-peptide in the mouse serum confirmed that the glycemia was normalized by the transplanted human cells. This approach offers the potential of a novel source of cells for transplantation into patients with type 1 diabetes. Topics: Animals; Blood Glucose; C-Peptide; Cell Differentiation; Diabetes Mellitus, Type 1; DNA-Binding Proteins; Female; Gene Expression; Hepatocytes; Homeodomain Proteins; Humans; Hyperglycemia; Insulin; Mice; Mice, Inbred NOD; Mice, SCID; Stem Cell Transplantation; Stem Cells; Telomerase; Trans-Activators; Transduction, Genetic; Transplantation, Heterologous | 2003 |
Incretin secretion in relation to meal size and body weight in healthy subjects and people with type 1 and type 2 diabetes mellitus.
Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretin hormones secreted in response to meal ingestion, thereby enhancing postprandial insulin secretion. Therefore, an attenuated incretin response could contribute to the impaired insulin responses in patients with diabetes mellitus. The aim of the present investigation was to investigate incretin secretion, in obesity and type 1 and type 2 diabetes mellitus, and its dependence on the magnitude of the meal stimulus. Plasma concentrations of incretin hormones (total, reflecting secretion and intact, reflecting potential action) were measured during two meal tests (260 kcal and 520 kcal) in eight type 1 diabetic patients, eight lean healthy subjects, eight obese type 2 diabetic patients, and eight obese healthy subjects. Both in diabetic patients and in healthy subjects, significant increases in GLP-1 and GIP concentrations were seen after ingestion of both meals. The incretin responses were significantly higher in all groups after the large meal, compared with the small meal, with correspondingly higher C-peptide responses. Both type 1 and type 2 diabetic patients had normal GIP responses, compared with healthy subjects, whereas decreased GLP-1 responses were seen in type 2 diabetic patients, compared with matched obese healthy subjects. Incremental GLP-1 responses were normal in type 1 diabetic patients. Increased fasting concentrations of GIP and an early enhanced postprandial GIP response were seen in obese, compared with lean healthy subjects, whereas GLP-1 responses were the same in the two groups. beta-cell sensitivity to glucose, evaluated as the slope of insulin secretion rates vs. plasma glucose concentration, tended to increase in both type 2 diabetic patients (29%, P = 0.19) and obese healthy subjects (22% P = 0.04) during the large meal, compared with the small meal, perhaps reflecting the increased incretin response. We conclude: 1) that a decreased GLP-1 secretion may contribute to impaired insulin secretion in type 2 diabetes mellitus, whereas GIP and GLP-1 secretion is normal in type 1 diabetic patients; and 2) that it is possible to modulate the beta-cell sensitivity to glucose in obese healthy subjects, and possibly also in type 2 diabetic patients, by giving them a large meal, compared with a small meal. Topics: Adult; Aged; Blood Glucose; Body Weight; C-Peptide; Case-Control Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Feeding Behavior; Female; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Obesity; Peptide Fragments; Protein Precursors; Random Allocation | 2003 |
Insulin independence following isolated islet transplantation and single islet infusions.
To restore islet function in patients whose labile diabetes subjected them to frequent dangerous episodes of hypoglycemic unawareness, and to determine whether multiple transplants are always required to achieve insulin independence.. The recent report by the Edmonton group documenting restoration of insulin independence by islet transplantation in seven consecutive patients with type 1 diabetes differed from previous worldwide experience of only sporadic success. In the Edmonton patients, the transplanted islet mass critical for success was approximately more than 9,000 IEq/kg of recipient body weight and required two or three separate transplants of islets isolated from two to four cadaveric donors. Whether the success of the Edmonton group can be recapitulated by others, and whether repeated transplants using multiple donors will be a universal requirement for success have not been reported.. The authors report their treatment with islet transplantation of nine patients whose labile type 1 diabetes was characterized by frequent episodes of dangerous hypoglycemia.. In each of the seven patients who have completed the treatment protocol (i.e., one or if necessary a second islet transplant), insulin independence has been achieved. In five of the seven patients only a single infusion of islets was required. To date, only one recipient has subsequently lost graft function, after an initially successful transplant. This patient suffered recurrent hyperglycemia 9 months after the transplant.. This report confirms the efficacy of the Edmonton immunosuppressive regimen and indicates that insulin independence can often be achieved by a single transplant of sufficient islet mass. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Immunosuppressive Agents; Islets of Langerhans Transplantation; Recovery of Function | 2003 |
Metabolic effects of a corticosteroid-free immunosuppressive regimen in recipients of pancreatic transplant.
A corticosteroid (CS)-free immunosuppressive regimen may be considered less diabetogenic than treatments including CSs principally after pancreas transplantation.. To test whether a CS-free immunosuppressive treatment is metabolically superior to a regimen including CSs, we prospectively studied 19 CS-free simultaneous pancreas and kidney (SPK) transplant recipients (body mass index=22+/-1 kg/m2; cyclosporine dose=400+/-19 mg/kg/day; azathioprine dose=77+/-8 mg/day; basal plasma C-peptide=1.3+/-0.12 ng/mL) and 12 matched CS-treated SPK transplant recipients (prednisone dose=9+/-1 mg/day; basal C-peptide=2.2+/-0.2 ng/mL) by means of the 6,6-2H(2)-glucose infusion and the euglycemic insulin clamp (1 mU/kg/min, insulin infusion rate). In addition, six renal transplant recipients receiving a CS-free regimen were also studied as a control group.. In the postabsorptive state, CS-treated SPK transplant recipients demonstrated comparable plasma glucose levels but higher plasma insulin levels than CS-free SPK transplant recipients. Plasma triglyceride levels were significantly higher in CS-treated SPK patients than in CS-free SPK patients (1.16+/-0.16 mg/dL vs. 0.88+/-0.08; P<0.05). High-density lipoprotein and apoprotein A(1) levels were similar in both groups. No difference was observed in pyruvate, lactate, beta-OH-butyrate, and basal endogenous glucose production in all three groups of patients studied. During euglycemic hyperinsulinemia, the inhibition of endogenous glucose production and the stimulation of tissue glucose disposal were not statistically different among the three groups.. SPK recipients receiving chronic low-dose CS maintenance therapy do not present a lower glucose disposal than CS-free recipients. Nonetheless, this is obtained at the expense of a higher endogenous insulin secretion, which can cause an alteration of the triglyceride profile. Topics: Adrenal Cortex Hormones; Adult; Azathioprine; Blood Glucose; C-Peptide; Cyclophosphamide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Glucose Tolerance Test; Humans; Immunosuppressive Agents; Kidney Transplantation; Kinetics; Male; Pancreas Transplantation; Prednisone | 2003 |
[Factors involved in ketoacidosis at the onset of type 1 diabetes in childhood].
In some patients the ketoacidosis at the onset of type 1 diabetes has been observed.. The aim of this study was to investigate an effect of the clinical, genetic, immunological and metabolic parameters on the occurrence of ketoacidosis at the clinical onset of the disease.. 106 children with type 1 diabetes, aged 1.8-18.2 years (average 10.6), 40 female and 66 male, were studied. Diabetic ketoacidosis was defined as blood pH of less than 7.35 and severe acidosis as less than 7.2. Among the clinical features, age at onset of the disease and gender of patients were evaluated. Moreover, fasting C-peptide level, insulin requirement, HbA1c level, blood glucose level and body mass index normalized by age and sex were examined at the onset and 6, 12, 24 and 36 months after diagnosis. The HLA-DQA1 and DQB1 alleles and -23 HphI INS polymorphism and CTLA4 gene +49 polymorphism (PCR-RFLP) were studied and islet cell antibodies (ICA) as well as antibodies to glutamic acid decarboxylase (GADA) and thyrosine phosphatase antibodies (IA2A) were also determined.. The presence of diabetic ketoacidosis was observed in 55% and severe form in 9% of children. In the group of patients with ketoacidosis lower C-peptide level and lower c-peptide/glycaemia ratio than in children without ketoacidosis were observed (0.20+/-0.18 vs. 0.31+/-0.28 pmol/ml and 0.07+/-0.05 vs. 0.20+/-0.17, p<0.003, respectively). The patients with fasting C-peptide at the onset below normal range (<0.28 pmol/ml) were at high risk of ketoacidosis, OR (95%CI)=3.3 (1.3-8.2). The patients with ketoacidosis were characterized by higher exogenous insulin requirement than non-ketoacidosis individuals (1.2+/-0.6 vs. 0.8+/-0.5 j/kg/24h, p=0.004). Besides, in patients with severe ketoacidosis higher level of IA2A was found as compared to other patients (73.4+/-44.9 vs. 44.2+/-39.6; p=0.04). In this group more frequently 2 and/or 3 different autoantibodies were observed (90% vs. 79%), although, the difference was not significant.. The presence of diabetic ketoacidosis at clinical diagnosis of type 1 diabetes may be related to the residual b cell function, which is mainly determined by the intensity of immunological destruction. Topics: Adolescent; Age Distribution; Age of Onset; Blood Glucose; Body Mass Index; C-Peptide; Child; Child, Preschool; Comorbidity; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Infant; Insulin; Male; Poland; Risk Factors; Sex Distribution | 2003 |
Comparison of insulin aspart and lispro: pharmacokinetic and metabolic effects.
To compare insulin levels and actions in patients with type 1 diabetes after subcutaneous injection of the rapid-acting insulin analogs aspart and lispro.. Seven C-peptide-negative patients with type 1 diabetes (two men and five women) were studied at the General Clinical Research Center at Temple University Hospital two times, 1 month apart. Their plasma glucose was normalized overnight by intravenous infusion of insulin. The next morning, they received subcutaneous injections of either aspart or lispro (9.4 +/- 1.9 U) in random order. For the next 4-5 h, their plasma glucose was clamped at approximately 5.5 mmol/l with a variable infusion of 20% glucose. The study was terminated after 8 h.. Both insulin analogs produced similar serum insulin levels (250-300 pmol/l) at approximately 30 min and disappeared from serum after approximately 4 h. Insulin aspart and lispro had similar effects on glucose and fat metabolism. Effects on carbohydrate metabolism (glucose uptake, glucose oxidation, and endogenous glucose production) peaked after approximately 2-3 h and disappeared after approximately 5-6 h. Effects on lipid metabolism (plasma free fatty acid, ketone body levels, and free fatty acid oxidation) appeared to peak earlier (at approximately 2 h) and disappeared earlier (after approximately 4 h) than the effects on carbohydrate metabolism.. We conclude that both insulin aspart and lispro are indistinguishable from each other with respect to blood levels and that they are equally effective in correcting abnormalities in carbohydrate and fat metabolism in patients with type 1 diabetes. Topics: Adult; Blood Glucose; Body Mass Index; C-Peptide; Calorimetry, Indirect; Diabetes Mellitus, Type 1; Female; Glucose; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Insulin Aspart; Insulin Lispro; Male | 2003 |
O(6)-methylguanine DNA methyltransferase activity in diabetic patients.
In the present study, we evaluated O(6)-methylguanine-DNA methyltransferase (MGMT) activity in diabetic patients. The study was performed on 27 patients with Type 1 diabetes, and 42 with Type 2 diabetes. Patients with complications were excluded from the study. 36 non-diabetic volunteers, non-smokers who do not consume alcoholic beverage, were chosen from the medical staff as control subjects. MGMT activity was measured by the transfer of radiolabeled methyl groups from a prepared methylguanine-DNA substrate to the enzyme fraction of leukocyte extract. Leukocyte MGMT activity was significantly reduced in both Type 1 and Type 2 diabetes patients as compared with control subjects (P<0.001). The present study demonstrates decreased MGMT activity in leukocytes from patients with Type 1 and Type 2 diabetes. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Leukocytes; Male; Middle Aged; O(6)-Methylguanine-DNA Methyltransferase; Patient Selection; Reference Values | 2003 |
Simultaneous occurrence of diabetes mellitus and juvenile dermatomyositis: report of two cases.
The simultaneous occurrence of juvenile dermatomyositis (DMS) and diabetes mellitus is described in 2 pediatric patients. Both these patients presented with significant weight loss, polyuria, and polydypsia within a short time of being diagnosed with JDMS, while these patients were taking oral prednisone (40-60 mg/day in divided doses). Laboratory evaluation detected ketonuria, significant hyperglycemia (696 and 913 mg/dL) and low serum levels of insulin and C-peptide. Both these patients were treated with high doses of insulin. Islet cell and GAD65 antibodies were found to be positive in 1 of the patients, pointing toward a diagnosis of insulin-dependent diabetes mellitus. The other patient tested negative for these antibodies and required insulin therapy for approximately 6 months. Steroid-induced diabetes mellitus seemed highly likely in this case. We hypothesize that a common environmental trigger possibly a viral infection might have been responsible in causing 2 different autoimmune pathologies in these genetically predisposed individuals. Topics: Adolescent; Adrenal Cortex Hormones; Autoimmune Diseases; C-Peptide; Dermatomyositis; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Risk Assessment; Treatment Outcome | 2003 |
Islet transplantation is associated with improvement of renal function among uremic patients with type I diabetes mellitus and kidney transplants.
The potential effects of islet transplantation on the renal function of 36 patients with type I diabetes mellitus and kidney transplants were studied with 4 yr of follow-up monitoring. Kidney-islet recipients were divided into two groups, i.e., patients with successful islet transplants (SI-K group) (n = 24, fasting C-peptide levels of >0.5 ng/ml for >1 yr) and patients with unsuccessful islet transplants (UI-K group) (n = 12, fasting C-peptide levels of <0.5 ng/ml). Kidney graft survival rates and function, urinary albumin excretion rates, and sodium handling were compared. Na(+)/K(+)-ATPase activity in protocol kidney biopsies and in red blood cells was cross-sectionally analyzed. The SI-K group demonstrated better kidney graft survival rates (100, 83, and 83% at 1, 4, and 7 yr, respectively) than did the UI-K group (83, 72, and 51% at 1, 4, and 7 yr, respectively; P = 0.02). The SI-K group demonstrated reductions in exogenous insulin requirements and higher C-peptide levels, compared with the UI-K group, whereas GFR values were similar. Microalbuminuria (urinary albumin index) increased significantly in the UI-K group only (UI-K, from 92.0 +/- 64.9 to 183.8 +/- 83.8, P = 0.05; SI-K, from 108.5 +/- 53.6 to 85.0 +/- 39.0, NS). In the SI-K group, but not in the UI-K group, natriuresis decreased at 2 and 4 yr (P < 0.01). The SI-K group demonstrated greater Na(+)/K(+)-ATPase immunoreactivity in renal tubular cells (P = 0.05) and higher activity in red blood cells (P = 0.03), compared with the UI-K group. The Na(+)/K(+)-ATPase activity in red blood cells was positively correlated with circulating C-peptide levels but not with glycated hemoglobin levels. Successful islet transplantation was associated with improvements in kidney graft survival rates and function among uremic patients with type I diabetes mellitus and kidney grafts. Topics: Albumins; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Erythrocytes; Glomerular Filtration Rate; Graft Rejection; Graft Survival; Humans; Islets of Langerhans Transplantation; Kidney; Kidney Transplantation; Renin-Angiotensin System; Sodium; Sodium-Potassium-Exchanging ATPase; Time Factors; Uremia | 2003 |
Proinsulin C-peptide replacement in type 1 diabetic BB/Wor-rats prevents deficits in nerve fiber regeneration.
We recently reported that early gene responses and expression of cytoskeletal proteins are perturbed in regenerating nerve in type 1 insulinopenic diabetes but not in type 2 hyperinsulinemic diabetes. We hypothesized that these differences were due to impaired insulin action in the former type of diabetes. To test this hypothesis, type 1 diabetic BB/Wor-rats were replaced with proinsulin C-peptide, which enhances insulin signaling without lowering blood glucose. Following sciatic nerve crush injury, early gene responses such as insulin-like growth factor, c-fos, and nerve growth factor were examined longitudinally in sciatic nerve. Neurotrophic factors, their receptors, and beta-tubulin and neurofilament expression were examined in dorsal root ganglia. C-peptide replacement significantly normalized early gene responses in injured sciatic nerve and partially corrected the expression of endogenous neurotrophic factors and their receptors, as well as neuroskeletal protein in dorsal root ganglia. These effects translated into normalization of axonal radial growth and significantly improved axonal elongation of regenerating fibers in C-peptide-replaced BB/Wor-rats. The findings in C-peptide replaced type 1 diabetic rats were similar to those previously reported in hyperinsulinemic and iso-hyperglycemic type 2 BB/Z-rats. We conclude that impaired insulin action may be more important than hyperglycemia in suppressing nerve fiber regeneration in type 1 diabetic neuropathy. Topics: Animals; C-Peptide; Cytoskeletal Proteins; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Disease Models, Animal; Immunohistochemistry; Insulin; Insulin-Like Growth Factor I; Male; Nerve Crush; Nerve Degeneration; Nerve Growth Factor; Nerve Growth Factors; Nerve Regeneration; Proto-Oncogene Proteins c-fos; Rats; Rats, Inbred BB; Receptor, IGF Type 1; Receptors, Nerve Growth Factor; Sciatic Nerve | 2003 |
Combined pancreas-kidney transplantation: a new program in Portugal, results from the first 12 cases.
Topics: Adult; Blood Glucose; C-Peptide; Cholesterol; Creatinine; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Kidney Transplantation; Pancreas Transplantation; Retrospective Studies; Treatment Outcome; Triglycerides | 2003 |
Interferon-alpha reduces insulin resistance and beta-cell secretion in responders among patients with chronic hepatitis B and C.
This study aimed at elucidating the effects of interferon (IFN)-alpha on glucose metabolism in patients with chronic hepatitis B and C infections. Twenty-eight biopsy-proven patients with chronic hepatitis B (ten cases) and hepatitis C (18 cases) were given IFN-alpha for a total of 24 weeks. The patients received a 75 g oral glucose tolerance test (OGTT), glucagon stimulation test, tests for type 1 diabetes-related autoantibodies and an insulin suppression test before and after IFN-alpha therapy. Ten of the 28 patients responded to IFN-alpha therapy. Steady-state plasma glucose of the insulin suppression test decreased significantly in responders (13.32+/-1.48 (S.E.M.) vs 11.33+/-1.19 mmol/l, P=0.0501) but not in non-responders (12.29+/-1.24 vs 11.11+/-0.99 mmol/l, P=0.2110) immediately after completion of IFN-alpha treatment. In the oral glucose tolerance test, no significant difference was observed in plasma glucose in either responders (10.17+/-0.23 vs 10.03+/-0.22 mmol/l) or non-responders (10.11+/-0.22 vs 9.97+/-0.21 mmol/l) 3 Months after completion of IFN-alpha treatment. However, significant differences were noted in C-peptide in both responders (2.90+/-0.13 vs 2.20+/-0.09 nmol/l, P=0.0040) and non-responders (2.45+/-0.11 vs 2.22+/-0.08 nmol/l, P=0.0287) before vs after treatment. The changes of C-peptide in an OGTT between responders and non-responders were also significantly different (P=0.0028), with responders reporting a greater reduction in C-peptide. No case developed autoantibodies during the treatment. In patients who were successfully treated with IFN-alpha, insulin sensitivity improved and their plasma glucose stayed at the same level without secreting as much insulin from islet beta-cells. Topics: Adult; Alanine Transaminase; Analysis of Variance; Autoantibodies; Blood Glucose; C-Peptide; Chi-Square Distribution; Diabetes Mellitus, Type 1; DNA, Viral; Female; Glucagon; Glucose Tolerance Test; Hepatitis B e Antigens; Hepatitis B, Chronic; Hepatitis C, Chronic; Homeostasis; Humans; Insulin; Insulin Resistance; Insulin Secretion; Interferon-alpha; Islets of Langerhans; Male; Middle Aged | 2003 |
Pediatric donor organs for pancreas transplantation: an underutilized resource?
Topics: Adult; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Follow-Up Studies; Glycated Hemoglobin; Humans; Pancreas Transplantation; Time Factors; Tissue Donors; Treatment Outcome | 2003 |
Insulin is required for prandial ghrelin suppression in humans.
Accumulating evidence indicates that ghrelin plays a role in regulating food intake and energy homeostasis. In normal subjects, circulating ghrelin concentrations decrease after meal ingestion and increase progressively before meals. At present, it is not clear whether nutrients suppress the plasma ghrelin concentration directly or indirectly by stimulating insulin secretion. To test the hypothesis that insulin regulates postprandial plasma ghrelin concentrations in humans, we compared the effects of meal ingestion on plasma ghrelin levels in six C-peptide-negative subjects with type 1 diabetes and in six healthy subjects matched for age, sex, and BMI. Diabetic subjects were studied during absence of insulin (insulin withdrawal study), with intravenous infusion of basal insulin (basal insulin study) and subcutaneous administration of a prandial insulin dose (prandial insulin study). Meal intake suppressed plasma ghrelin concentrations (nadir at 105 min) by 32 +/- 4% in normal control subjects, 57 +/- 3% in diabetic patients during the prandial insulin study (P < 0.002 vs. control subjects), and 38 +/- 8% during basal insulin study (P = 0.0016 vs. hyperinsulinemia; P = NS vs. control subjects) but did not have any effect in the insulin withdrawal study (P < 0.001 vs. other studies). In conclusion, 1). insulin is essential for meal-induced plasma ghrelin suppression, 2). basal insulin availability is sufficient for postprandial ghrelin suppression in type 1 diabetic subjects, and 3). lack of meal-induced ghrelin suppression caused by severe insulin deficiency may explain hyperphagia of uncontrolled type 1 diabetic subjects. Topics: Adult; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Eating; Female; Ghrelin; Humans; Infusions, Intravenous; Injections, Subcutaneous; Insulin; Male; Middle Aged; Peptide Hormones | 2003 |
The variable but inevitable loss of beta cells in overt type 1 diabetes.
Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Islets of Langerhans | 2003 |
The severity of clinical presentation of type 1 diabetes in children does not significantly influence the pattern of residual beta-cell function and long-term metabolic control.
The purpose of the present study was to compare relationships between the clinical presentation of type 1 diabetes in children and residual beta-cell secretion and long-term metabolic control.. This retrospective study was conducted in 66 diabetic children with age at diagnosis ranging from 0.7 to 14.8 yr. The patients showed contrasting characteristics at diagnosis: either diabetic ketoacidosis (DKA) (group 1, n = 29) or absence of metabolic derangement (group 2, n = 37) associated with marked (group 2A, n = 12) or mild hyperglycemia (group 2B, n = 25). A regular follow-up was available for at least 10 yr (10-32 yr) in all cases and for 20 yr in 23 cases. C-peptide levels were measured from diagnosis and thereafter at intervals for the first years of disease until becoming permanently undetectable.. C-peptide levels at diagnosis were undetectable in about 20% of the cases both with and without DKA. C-peptide levels at diagnosis, the duration of measurable C-peptide levels and the maximum value found during follow-up were not significantly different in the three groups and were not correlated with glycated hemoglobin (GHb) calculated throughout the whole period. No differences were found between the groups of patients concerning GHb values and insulin dose at 10, 15 and 20 yr of disease. The patients of group 2A, characterized by an extremely high glycemic level without ketoacidosis, had a significantly higher prevalence of HLA DR3/4 heterozygosity.. The severity of clinical presentation at diagnosis does not significantly influence residual beta-cell function, and long-term metabolic control. Topics: Adolescent; Adult; Blood; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Glycated Hemoglobin; Heterozygote; HLA-DR3 Antigen; HLA-DR4 Antigen; Humans; Hydrogen-Ion Concentration; Hyperglycemia; Islets of Langerhans; Retrospective Studies | 2003 |
Kinetics of diabetes-associated autoantibodies after sequential intraportal islet allograft associated with kidney transplantation in type 1 diabetes.
Presence or occurrence of pancreas auto-antibodies (aAb) has been shown to be of poor prognosis for islet cell transplantation. The aim of the study was to monitor the kinetics of these aAb after sequential intra-portal islet plus kidney transplantation with pre-Edmonton immunosuppressive regimen in order to determine whether the sequential protocol of transplantation was involved in the occurrence of the immune response.. Three patients with IDDM and a previous (IAK) or simultaneous (SIK) kidney transplantation received 3 or 4 ABO compatible islet preparations. Islets (> 8 000 IEQ/kg post culture) were sequentially transplanted within a 12 day period via a per-cutaneous catheter. Immunosuppressive treatment included cyclosporine, steroïds and mycophenolate. Plasma ICAs, GAD 65, IA2 and C peptide (C-p) levels were monitored. Type II HLA phenotype was determined in donors and recipients.. Patient #1 had high anti-GAD levels (26.5 UI/l) before the IAK, while anti-IA2 and ICA levels were low. After the transplantation, C-p levels increased to 4.9 ng/ml at one month before becoming undetectable at 2 months. GAD levels remained high, ICA and IA2 aAb were undetectable. Patients #2 and #3 did not have significant levels of aAb before the islet transplantation. A slight increase in GAD was observed with each islet transplantation, followed by an overt but transient increase in ICA. IA2 levels remained undetectable. Three months after the transplantation and 2 weeks after the increase of ICA, C-p levels, that were >3.4 ng/ml at one month, fell below 0.2 (N: 0.5-2).. The immunosuppressive regimen used in kidney transplantation is unable to control perfectly anti-pancreas aAb production. Moreover, these results seem to indicate that the benefits of sequential islet transplantation lie more in the increased islet mass they provide than in potential immune benefit. Topics: Adrenal Cortex Hormones; Adult; Autoantibodies; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Humans; Immunosuppressive Agents; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Isoenzymes; Kidney Transplantation; Kinetics; Mycophenolic Acid; Pancreas; Prognosis | 2003 |
Evaluation of the beta cell response by C-peptide measurement in parents of children with type I diabetes.
Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulinoma; Islets of Langerhans; Male; Parents | 2003 |
[C-peptide as the decisive factor for classification of type 1 diabetes mellitus and type 2 diabetes mellitus].
The main objective was to seek, based on defined groups of diabetics, C-peptide levels on fasting and after stimulation which would help to differentiate diabetes mellitus type 1 from diabetes mellitus type 2 in patients with manifestation of diabetes in adult age. GROUPS: Group A comprised 65 non-obese diabetics type 2 with failure of PAD treatment. Group B included 304 newly manifested diabetics type 1 and 2 aged 31-65 years. Group C was formed by 424 patients with diabetes mellitus type 1 and type 2 with different duration of diabetes.. Group A: mean C-peptide levels on fasting 0.32 and after stimulation with a standard breakfast 0.59 pmol/ml suggest absolute insulin deficiency in type 2 diabetics with failure of PAD treatment. Group B: 29.2% diabetics type 1 had already during manifestation of diabetes C-peptide levels on fasting < 0.43 pmol/ml and 47.9% C-peptide of < 0.6 after a meal. There were 1.9 and 4.9% subjects among type 2 diabetics with such low C-peptide levels. After a six-year follow up the mean C-peptide levels on fasting declined in type 1 diabetics from 0.49 to 0.16 pmol/ml and in patients originally with type 2 diabetes reclassified to type 1 the levels dropped from 0.56 to 0.26 pmol/ml. Group C served as the basic group for statistically (linear regression method) detected discrimination values of C-peptide differentiating diabetes mellitus type 1 and diabetes mellitus type 2--the liminal value being 0.59 pmol/ml on fasting and 1.0 pmol/ml after a meal.. In clinical practice it is not possible to assess reliably slowly manifesting diabetes type 1 (LADA by age, BMI and compensation of diabetes. Positivity of antiGAD antibodies does not rule out diabetes mellitus type 1. In unequivocal cases the decisive factor is therefore the C-peptide level on fasting and after a meal. Topics: Adult; Aged; Autoantibodies; Autoantigens; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Glutamate Decarboxylase; Humans; Male; Membrane Proteins; Middle Aged; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Receptor-Like Protein Tyrosine Phosphatases, Class 8 | 2002 |
Incidence of cytomegalovirus infections after immunosuppression induction in clinical islet transplantation and impact on graft function.
Topics: C-Peptide; Cytomegalovirus; Cytomegalovirus Infections; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Graft Survival; Histocompatibility Testing; Humans; Immunosuppressive Agents; Incidence; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Postoperative Complications; Transplantation, Homologous; Virus Replication | 2002 |
Insulin, but not proinsulin C-peptide, enhances platelet fibrinogen binding in vitro in Type 1 diabetes mellitus patients and healthy subjects.
Insulin treatment is essential in Type 1 diabetes mellitus (DM). However, previous studies have shown complex effects of insulin on platelet function. Proinsulin C-peptide has shown beneficial effects in Type 1 DM, but it is not known if it can affect platelet activation. We thus investigated how insulin, C-peptide, and their combination influence platelets from DM patients and healthy subjects.. Hirudinized blood from patients (n = 10) and healthy subjects (n = 10) was preincubated in the absence or presence of insulin (10 and 100 microU/ml), C-peptide (0.3, 1, and 10 nM), or the combination (1 nM C-peptide + 100 microU/ml insulin or 10 nM C-peptide + 100 microU/ml insulin) and further incubated without or with 10(-6) M ADP. Platelet activation was monitored by platelet fibrinogen binding and P-selectin expression using whole blood flow cytometry. Data are presented as binding index (BI), which integrates the percentage of activated cells and their mean fluorescence intensity.. Insulin enhanced ADP-induced platelet fibrinogen binding in both Type 1 DM patients and healthy subjects. For example, ADP-stimulated platelet fibrinogen BI increased from 4.25 +/- 0.74 to 8.63 +/- 2.00 with 10 microU/ml insulin (P < .05) in Type 1 DM patients. However, insulin did not increase platelet P-selectin expression. Proinsulin C-peptide did not influence platelet fibrinogen binding or P-selectin expression in either Type 1 DM patients or healthy subjects. The combination of C-peptide and insulin had similar effects as insulin alone.. Insulin at physiological concentrations enhances platelet fibrinogen binding in both Type 1 DM patients and healthy subjects, whilst C-peptide does not influence platelet activation. Topics: Adenosine Diphosphate; Adult; Blood Platelets; C-Peptide; Diabetes Mellitus, Type 1; Fibrinogen; Humans; Insulin; Male; Middle Aged; P-Selectin; Peptides; Platelet Activation; Protein Binding; Receptors, Fibrinogen; Stimulation, Chemical | 2002 |
A case of fulminant type 1 diabetes with graves' disease.
Topics: Adult; Amylases; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Graves Disease; Humans; Ketone Bodies; Lipase; Pregnancy; Pregnancy in Diabetics | 2002 |
Skepticism surrounds diabetes xenograft experiment.
Topics: Animals; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans Transplantation; Male; Mexico; Sertoli Cells; Swine; Transplantation, Heterologous | 2002 |
Reduction of hepatic glycogen synthesis and breakdown in patients with agenesis of the dorsal pancreas.
In a family with agenesis of the dorsal pancreas only the mother presents with insulin-dependent diabetes mellitus, whereas her sons are glucose tolerant. We examined whether metabolic defects can be detected early in this disease. Plasma glucose profiles were obtained from patients with dorsal pancreas agenesis and from matched healthy subjects. Hepatic glycogen synthesis and breakdown were determined from the time course of glycogen concentrations using noninvasive (13)C nuclear magnetic resonance spectroscopy. Gluconeogenesis was calculated from the difference between glucose production (measured with D-[6,6-(2)H(2)]glucose) and glycogen breakdown. Frequently sampled iv glucose tolerance tests were performed to assess insulin secretion and sensitivity. The mean plasma glucose level was higher (12.9 +/- 0.4 vs. 5.9 +/- 0.1 mmol/liter), whereas the peak plasma insulin level was lower (236 vs. 397 +/- 23 pmol/liter) in the diabetic mother than in her nondiabetic sons and healthy subjects. In all patients, however, glycogen synthesis and breakdown were reduced by approximately 55% (P < 0.05) and 40% (P < 0.02), respectively. Gluconeogenesis (6.8 +/- 0.8 vs. 4.2 +/- 0.3 micro mol/kg.min; P < 0.05) and hepatic insulin clearance (6.8 +/- 1.3 vs. 2.8 +/- 1.0 ml/kg.min) were increased in all patients. In conclusion, patients with complete agenesis of the dorsal pancreas exhibit marked defects in hepatic glycogen metabolism, which are present even in the nondiabetic offspring. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Gluconeogenesis; Glucose Tolerance Test; Glycogen; Human Growth Hormone; Humans; Hydrocortisone; Insulin; Insulin Resistance; Insulin Secretion; Kinetics; Leptin; Liver; Magnetic Resonance Spectroscopy; Male; Middle Aged; Norepinephrine; Pancreas | 2002 |
Residual insulin secretion is not coupled to a maintained glucagon response to hypoglycaemia in long-term type 1 diabetes.
To evaluate the influence of residual beta-cell function on glucagon secretion and glucose counter-regulation following hypoglycaemia in type 1 diabetes.. The hormonal counter-regulatory responses to standardized insulin-induced hypoglycaemia were investigated, 18 patients with type 1 diabetes of long duration and 12 healthy subjects were investigated. Nine of the diabetic patients (diabetes duration 17 +/- 1 years) had residual insulin secretion, as reflected by persistent urinary C-peptide excretion. The other nine diabetic patients (diabetes duration 21 +/- 1 years) were C-peptide negative.. Similar hypoglycaemic nadirs were found in all groups (2.1-2.3 mmol L-1), whereas the recovery of plasma glucose levels was delayed similarly in the diabetic groups. In the control subjects, plasma glucagon increased ( approximately 50%). No significant glucagon response was registered in either of the two diabetic groups. The maximum plasma adrenaline and pancreatic polypeptides (PP) responses to hypoglycaemia were comparable in the two diabetic patient groups; the peak values being lower (P < 0.05) than in the controls. Plasma noradrenaline, growth hormone and cortisol responses to hypoglycaemia were similar in all three groups.. Residual beta-cell function in patients with long-term type 1 diabetes is not accompanied by preservation of the glucagon response to hypoglycaemia. As the two markers of autonomic function (adrenaline and PP) were similarly reduced in the two diabetic groups, the findings instead favour the concept that the defective glucagon secretory response to hypoglycaemia is because of autonomic nervous dysfunction. Topics: Adult; Autonomic Nervous System; Blood Glucose; C-Peptide; Data Interpretation, Statistical; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Growth Hormone; Humans; Hydrocortisone; Hypoglycemia; Infusions, Intravenous; Injections, Subcutaneous; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Pancreatic Polypeptide; Radioimmunoassay; Time Factors | 2002 |
HLA-DQ genotypes in classic type 1 diabetes and in latent autoimmune diabetes of the adult.
In 1993-1996, islet autoantibodies, C-peptide, and HLA-DQ genotypes were evaluated in 345 insulin-treated diabetic patients of all ages from the Skaraborg Diabetes Registry 5-6 years after their diagnosis and in 216 control subjects from the Skaraborg County, Sweden, population. The aims of this study were to clarify the importance of age at diagnosis of diabetes for HLA-DQ associations in patients with classic type 1 diabetes and whether patients considered to have latent autoimmune diabetes of the adult differed in their human leukocyte antigen (HLA) associations. An abnormally low fasting C-peptide value was used as the definition of type 1 diabetes, found in 182 of 345 (53%) patients. No major associations between age at diagnosis and HLA susceptibility or protective genotypes were detected in type 1 diabetic patients. Among the 163 patients with preserved beta-cell function, the frequency of HLA protective genotypes was clearly decreased (5% vs. 42%) in the 46 of 163 with islet antibodies compared with the 117 of 163 antibody-negative patients. The authors conclude that there were no major effects of age at diagnosis on HLA-DQ associations in classic type 1 diabetic patients, whereas lack of HLA-DQ protective genotypes was a feature of patients with slow-progressing type 1 diabetes (latent autoimmune diabetes of the adult). Topics: Age Factors; Autoantibodies; C-Peptide; Chi-Square Distribution; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; HLA-DQ Antigens; Humans; Male; Registries; Statistics, Nonparametric; Sweden | 2002 |
Clinical features of a young Japanese woman having marked obesity and abrupt onset of diabetes mellitus with ketoacidosis.
The subject was a 26-year-old Japanese woman of 148 cm height, 96.2 kg of body weight (BW) (body mass index (BMI) of 43.8 kg/m(2)). She was referred to our hospital on May 1, 2000 for the evaluation of marked hyperglycemia with clinical symptom of general malaise, polydipsia, and ketonuria (3+). She did not smoke, or drink alcohol. But, she tended to eat lots of sweet food every day before the onset of this symptom. Her father was diagnosed type 2 diabetes mellitus. Her fasting plasma glucose and HbA(1c), and serum C-peptide were 398 mg/dl, 7.8% and less than 0.05 ng/ml [normal range: 0.94-2.8], respectively. She tested negative for anti-glutamic acid decarboxylase (GAD) antibodies and islet-cell antibodies. C-peptide level in her urine was as low as 3.4 microg/day. We immediately started insulin treatment under the diagnosis of abrupt onset of diabetes mellitus with diabetic ketoacidosis on the day of her admission, and the insulin treatment was continued after her being discharged. She showed continuous BW reduction until her BW reached approximately 60 kg, followed by her BW being plateau. During the period, intra-abdominal visceral fat (VF) and subcutaneous fat (SF) volume assessed by helical computerized tomography (CT) showed a substantial reduction [3.9-0.5 l for VF, 19-3.2 l for SF volume]. Pre-heparin plasma lipoprotein lipase (LPL) mass showed a considerably lower value when she had continuous BW reduction than did it when her BW reduction discontinued. These findings suggest that in this subject, continuous BW reduction after the abrupt onset of diabetes is closely associated with intra-abdominal fat mass reduction, which may be related to decreased production of LPL. Topics: Adipose Tissue; Adult; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Insulin; Japan; Leptin; Lipids; Obesity; Regression Analysis; Tomography, X-Ray Computed | 2002 |
Two-year prospective evaluation of the factors affecting honeymoon frequency and duration in children with insulin dependent diabetes mellitus: the key-role of age at diagnosis.
The aim of this study was to investigate the influence of pre-treatment variables on subsequent insulin requirement (IR) and partial remission (PR) in children with insulin-dependent diabetes mellitus (T1DM). Sixty-seven children with newly diagnosed T1DM, admitted to our Clinic during a 3-year recruitment period, were longitudinally evaluated for 2 yr. Patients were characterized by sex, age, parental education, duration of symptomatic history at diagnosis, admission duration, ketoacidosis or absence of ketoacidosis and residual beta-cell activity. More than 80% of the children experienced a PR, which lasted more than 12 months in 41.7% and at least 24 months in 16.4% of cases. The prevalence of PR at different ages after T1DM onset was significantly lower in children diagnosed while younger than 5 years than in those diagnosed after 5 years. The mean duration of the remission period was 11.7 +/- 8.9 months, irrespectively of sex, duration of the symptomatic period preceding T1DM diagnosis, parental education, blood pH and base excess, HbA1c concentration and admission duration. Beta-cell residual function evaluated after glucagons stimulation test (basal and 6 min C-peptide) was statistically different in PR patients and in those who experienced no remission. Age at diagnosis was the only pre-treatment factor which, on stepwise regression analysis, affected both PR duration and IR at the end of follow-up. To conclude, honeymoon frequency and duration are strictly conditioned by both residual beta-cell function and IR at T1DM onset. Since IR is higher in younger subjects, early onset of T1DM can be considered the factor with the most detrimental influence on honeymoon incidence. Other pre-treatment variables have no significant impact on PR. Topics: Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Educational Status; Female; Glycated Hemoglobin; Humans; Hydrogen-Ion Concentration; Insulin; Longitudinal Studies; Male; Parents; Prospective Studies; Regression Analysis; Remission Induction; Time Factors | 2002 |
Reduction of plasma leptin concentrations by arginine but not lipid infusion in humans.
We examined short-term effects of arginine infusion on plasma leptin in diabetic and healthy subjects.. Arginine stimulation tests were performed in C-peptide negative type 1 [DM1; hemoglobin A(1c); 7.3 +/- 0.3%], hyperinsulinemic type 2 diabetic (DM2; 7.6 +/- 0.7%), and nondiabetic subjects (CON; 5.4 +/- 0.1%).. Fasting plasma leptin correlated linearly with body mass index among all groups (r = 0.61, p = 0.001). During arginine infusion, peak plasma insulin was lower in DM1 than in DM2 (p < 0.05) and CON (p < 0.01). Plasma leptin decreased within 30 minutes by approximately 11% in DM1 (p < 0.001), DM2 (p < 0.01), and CON (p < 0.005), slowly returning to baseline thereafter. Plasma free fatty acids (FFAs) were higher in DM1 (0.6 +/- 0.1 mM) and DM2 (0.6 +/- 0.1 mM) than in CON (0.4 +/- 0.1 mM, p < 0.05) and transiently declined by approximately 50% (p < 0.05) at 45 minutes in all groups before rebounding toward baseline. To examine the direct effects of FFAs on plasma leptin, we infused healthy subjects with lipid/heparin and glycerol during fasting, and somatostatin-insulin ( approximately 35 pM) -glucagon ( approximately 90 ng/mL) clamps were performed. In both protocols, plasma leptin continuously declined by approximately 25% (p < 0.05) during 540 minutes without any difference between the high and low FFA conditions.. Arginine infusion transiently decreased plasma leptin concentrations both in insulin-deficient and hyperinsulinemic diabetic patients, indicating a direct inhibitory effect of the amino acid but not of insulin or FFAs. Topics: Adult; Arginine; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fat Emulsions, Intravenous; Fatty Acids, Nonesterified; Glucagon; Glycerol; Heparin; Humans; Insulin; Kinetics; Leptin; Male; Middle Aged; Somatostatin | 2002 |
Intrahepatic islet transplantation in type 1 diabetic patients does not restore hypoglycemic hormonal counterregulation or symptom recognition after insulin independence.
Islet allotransplantation can provide prolonged insulin independence in selected individuals with type 1 diabetes. Whether islet transplantation also restores hypoglycemic counterregulation is unclear. To determine if hypoglycemic counterregulation is restored by islet transplantation, we studied hormone responses and hypoglycemic symptom recognition in seven insulin-independent islet transplant recipients using a 3-h stepped hypoglycemic clamp, and compared their responses to those of nontransplanted type 1 diabetic subjects and nondiabetic control subjects. Glucagon responses of islet transplant recipients to hypoglycemia were significantly less than that observed in control subjects (incremental glucagon [mean +/- SE]: -12 +/- 12 vs. 64 +/- 22 pg/ml, respectively; P < 0.05), and not significantly different from that of nontransplanted type 1 diabetic subjects (-17 +/- 10 pg/ml). Epinephrine responses and symptom recognition were also not restored by islet transplantation (incremental epinephrine [mean +/- SE]: 195 +/- 128 [islet transplant recipients] vs. 238 +/- 73 [type 1 diabetic subjects] vs. 633 +/- 139 pg/ml [nondiabetic control subjects], P < 0.05 vs. control; peak symptom scores: 3.3 +/- 0.9 [islet transplant recipients] vs. 3.1 +/- 1.1 [type 1 diabetic subjects] vs. 6.7 +/- 0.8 [nondiabetic control subjects]). Thus the results indicate that despite providing prolonged insulin independence and near-normal glycemic control in these patients with long-standing type 1 diabetes, hypoglycemic hormonal counterregulation and symptom recognition were not restored by intrahepatic islet transplantation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Hormones; Humans; Hypoglycemia; Insulin; Islets of Langerhans Transplantation; Liver; Male; Middle Aged | 2002 |
Anti-CD38 autoantibodies: characterisation in new-onset type I diabetes and latent autoimmune diabetes of the adult (LADA) and comparison with other islet autoantibodies.
Serum anti-CD38 autoantibodies (aAbs) have been reported in 17 to 19% of patients with long-standing Type I (insulin-dependent) diabetes mellitus and Type II (non-insulin-dependent) diabetes mellitus. Whether these aAbs are also found in new-onset Type I diabetes and in Latent Autoimmune Diabetes in Adults (LADA) is not known, as is their relationship with conventional islet aAbs.. These issues were addressed by studying new-onset Type I and LADA diabetic cohorts with a recently developed anti-CD38 enzymatic immuno-assay.. Anti-CD38 aAb prevalence among new-onset Type I patients (3.8%) was lower than previously found in long-standing Type I diabetes (11.7%, as defined with the 97.5 percentile cutoff; p=0.01), suggesting a late appearance of these aAbs. Among LADA patients, 14.9% were anti-CD38(+). Anti-CD38 were only associated with anti-GAD aAbs in new-onset Type I diabetes. Although the CD38 target molecule was expressed in human pancreatic islets, anti-CD38 aAbs did not contribute to the islet cell antibody (ICA) immunofluorescence reactivity. All the positive sera analysed for Ca(2+) release were found to mobilise it. In agreement with these agonistic features, anti-CD38(+) new-onset Type I patients showed higher fasting C-peptide values as compared to negative counterparts; the association was stronger when the analysis was limited to the agonistic anti-CD38(+) sera. A similar trend was found among LADA patients.. Anti-CD38 aAbs are distinct markers of islet autoimmunity which are more prevalent in long-standing disease, as opposed to the other known islet aAbs. Their in vitro agonistic properties could be operating in vivo as well, as they identify sub-groups of patients with higher residual beta-cell function. Topics: Adolescent; ADP-ribosyl Cyclase; ADP-ribosyl Cyclase 1; Aged; Antigens, CD; Autoantibodies; C-Peptide; Calcium; Case-Control Studies; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Male; Membrane Glycoproteins; Middle Aged | 2002 |
Achievement of insulin independence in three consecutive type-1 diabetic patients via pancreatic islet transplantation using islets isolated at a remote islet isolation center.
As a result of advances in both immunosuppressive protocols and pancreatic islet isolation techniques, insulin independence has recently been achieved in several patients with type 1 diabetes mellitus via pancreatic islet transplantation (PIT). Although the dissemination of immunosuppressive protocols is quite easy, transferring the knowledge and expertise required to isolate a large number of quality human islets for transplantation is a far greater challenge. Therefore, in an attempt to centralize the critical islet processing needed for islet transplantation and to avoid the development of another islet processing center, we have established a collaborative islet transplant program between two geographically distant transplant centers.. Three consecutive patients with type 1 diabetes mellitus with a history of severe hypoglycemia and metabolic instability underwent PIT at the Methodist Hospital (TMH), Houston, Texas, using pancreatic islets. All pancreatic islets were isolated from pancreata procured in Houston and subsequently transported for isolation to the Human Islet Cell Processing Facility of the Diabetes Research Institute (DRI) at the University of Miami, Miami, Florida. Pancreatic islets were isolated at DRI after enzymatic ductal perfusion (Liberase-HI) by the automated method (Ricordi Chamber) using endotoxin-free and xenoprotein-free media. After purification, the islets were immediately transported back to TMH and transplanted via percutaneous transhepatic portal embolization. Immunosuppression consisted of sirolimus, tacrolimus, and daclizumab.. After donor cross-clamp in Houston, donor pancreata arrived at DRI and the isolation process began within 6.5 hr in all cases (median, 5.4 hr; range, 4.8-6.5 hr). At the completion of the isolation process, the islets were immediately transported back to TMH and transplanted. All three patients attained sustained insulin independence after transplantation of 395,567, 394,381, and 563,206 pancreatic islet equivalents (IEQ), respectively. Despite insulin independence, the first two patients received less than 10,000 IEQ/kg; therefore, to increase their functional pancreatic islet reserve, they underwent a second islet transplant with 326,720 and 768,132 IEQ, respectively. Posttransplantation follow-up for these three patients is 4, 3, and 0.5 months, respectively. The mean glycosylated hemoglobin values have been dramatically reduced in the first two patients. In addition, the mean amplitude of glycemic excursions have also been reduced in all three recipients (patient 1: before transplantation 197 mg/dL vs. after transplantation 61 mg/dL; patient 2: before transplantation 202 mg/dL vs. after transplantation 52 mg/dL; patient 3: before transplantation 245 mg/dL vs. after transplantation 58 mg/dL) after PIT. All pancreatic islet allografts demonstrated the ability to respond to an in vitro glucose stimulus at the DRI before shipment and at TMH after shipment and final processing with a median stimulation index of 2.1 and 2.2, respectively. None of the transplant recipients have had a hyper- or hypoglycemic episode since PIT and no complications have occurred.. These early data demonstrate that (1) pancreatic islets remain viable after shipment to remote transplant sites; (2) pancreatic islet isolation techniques and experience can be concentrated at a small number of regional facilities that could supply islets to remote transplant centers; and (3) insulin independence via PIT can be achieved using a remote pancreatic islet isolation center. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Cooperative Behavior; Diabetes Mellitus, Type 1; Eating; Follow-Up Studies; Graft Survival; Humans; In Vitro Techniques; Insulin; Interinstitutional Relations; Islets of Langerhans; Islets of Langerhans Transplantation; Middle Aged; Postoperative Complications; Tissue and Organ Procurement; Transplantation, Homologous | 2002 |
A mathematical model for pattern of change in beta-cell reserve and factors affecting residual reserve within the first 2 years of type 1 diabetes.
The aim of this study was to investigate the effects of age, duration of diabetes, sex and ICA (Islet cell cytoplasmic antibody) on beta-cell reserves and to develop a model within the first 2 years of Type 1 diabetes. Beta-cell reserve is evaluated as fasting (FCp) and 1 mg i.v. glucagon stimulated C-peptide (SCp) levels in 58 Type 1 diabetics and in 12 normoglycemic subjects. Patients were divided into 3 groups according to duration of diabetes: Group I (2.5+/-0.3 weeks), Group II (13.4+/-1.2 months) and Group III (24.2+/-1.8 months). FCp/SCp level in nmol/l (mean+/-SE) were as follows. Group I: 0.21+/-0.02/0.38+/-0.04, Group II: 0.15+/-0.01/0.27+/-0.02, Group III: 0.07+/-0.01/0.11+/-0.02, CONTROL GROUP: 0.42+/-0.09/1.29+/-0.13. The scatter plots of C-peptide levels vs time in all the diabetic patients fitted in to a 4th-order polynomial regression (R: 0.96-0.98). Age was strongly correlated with FCp (rs: 0.46, p<0.05) and ICA positivity affected Cp-levels negatively (p>0.05). In conclusion, as the duration of diabetes increases, response time to glucagon prolongs and amplitude of it shortens. Duration of diabetes of less than 2 weeks, feminity, puberty and ICA positivity affect beta-cell reserve negatively, conversely, masculinity, post-puberty, older age and ICA negativity affect the reserve positively. The dynamics of C-peptide response to glucagon follow a mathematical model and Type 1 diabetes causes a decrease not only in the amplitude of the response but also in the duration of the response. Topics: Adolescent; Adult; Aging; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Humans; Islets of Langerhans; Male; Mathematics; Models, Biological; Time Factors | 2002 |
[Clinical heterogeneity of childhood diabetes in Baranya county].
Immune mediated type 1 diabetes is the most frequent form of childhood diabetes while type 2 and other forms are more rare in childhood in the Caucasian population. Differentiation of various diabetes subtypes has importance in the choice of treatment and prognosis.. The aim of the study was to describe clinical heterogeneity of childhood diabetes and to evaluate possibilities of phenotypical classification.. Two hundred twenty eight children (128 girls and 100 boys) with diabetes diagnosed at the Department of Pediatrics, University of Pécs, in the period of 1978-2000 were examined. Glycated hemoglobin levels, insulin requirement, body weight at diagnosis and association of type 1 diabetes with other disorders were analysed.. Thirty one patients (13.6%) had permanently low (< 8%) glycated hemoglobin levels. Low glycated hemoglobin level associated with low insulin requirement (< 0.5 U/kg/day) was observed in three patients (1.4%) with 4 years of disease duration and in 2 patients (0.9%) during the whole disease course. These patients can be classified as non-classical type 1 diabetes cases. Obesity associated with less than 0.5 U/kg/day insulin requirement observed at least for two years from diagnosis was found in 2 cases (0.9%). These cases may be diagnosed as having childhood type 2 diabetes. The authors identified two diabetes patients with Down syndrome while MODY and transient neonatal diabetes were observed in one cases each. Diabetes associated conditions diagnosed in single cases each were as follows: thymus tumor, Duchenne muscular dystrophy, autoimmune polyglandular syndrome type 2, and T-cell lymphoma.. Childhood diabetes cases can be classified into several subgroups on clinical grounds, insulin requirement, and glycemic control. The data suggest that the prevalence of type 2 and non-classical type 1 diabetes is probably only a few percent among children with diabetes in Hungary. Due to phenotypic overlap between different forms of diabetes, measurement of beta-cell specific autoantibodies and C peptide levels can be recommended for etiologic classification. Topics: Adolescent; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hungary; Hypoglycemic Agents; Insulin; Islets of Langerhans; Male; Phenotype; Severity of Illness Index; Time Factors | 2002 |
[Clinical, biochemical and immunological characteristic of diabetes type I, LADA, diabetes type II, and MODY patients].
Right classification of diabetes is important clinical issue. The aim of present study was to compare clinical, biochemical and immunological features, to analyze their practical use and to establish new decision tree which make the distinction between diabetes type 1, LADA, diabetes type 2 and MODY. We studied 97 not obese (mean BMI 26.3 +/- 4.9 kg/m2) patients aged 14 to 70 years, mean age 43 +/- 11.7 years, 53 women, 44 men. Mean duration of diabetes--2.3 +/- 4.3 years. We measured basal and stimulated C-peptide (6 minutes after 1 mg i.v. glucagon) (ELISA) and antibodies titers to glutamic acid decarboxylase--antiGAD65, tyrosine phosphatase-like molecule--IA2 and insulin--IAA (RIA). Autoimmune diabetes (LADA, type 1) was diagnosed with presence of one or more islet antigen antibodies. The highest frequencies had anti-GAD antibodies 33/97 (34%). The most complicated was to sort out group of patients with LADA. Comparison between this group and patients with diabetes type 2 have shown that BMI, co-existence of autoimmune disease, autoimmune markers and basal and stimulated C-peptide level measured at entry for the classification were useful in differentiation. Moreover we observed significantly lower C-peptide basal, stimulated and over basal level in group with MODY diabetes in comparison to diabetes type 2 patients. In the studied group were 5 patients with diabetes type 2 and obesity, in relatively young age. At the end there was one case of ADM (atypical diabetes mellitus). Clinical criteria for the classification of diabetes not always correlated with diagnosis. Autoimmune markers, basal and stimulated C-peptide were useful specially in differentiation between LADA and diabetes type 2 or diabetes type 1. Autoimmune diabetes co-existe with autoimmune disease. Proposed diagnostic scheme take for consideration presence of autoantibodies as well as C-peptide criteria. Topics: Adolescent; Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Enzyme-Linked Immunosorbent Assay; Female; Glutamate Decarboxylase; Humans; Insulin; Male; Middle Aged; Pedigree; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases | 2002 |
Preventing type 1 diabetes may someday become possible.
Topics: Adjuvants, Immunologic; Animals; C-Peptide; Chaperonin 60; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Drug Evaluation, Preclinical; Humans; Peptide Fragments; Peptides | 2002 |
Molecular detection of circulating beta-cells after islet transplantation.
Islet transplantation is a promising treatment for type 1 diabetes. However, islet grafts are submitted to multiple injuries, including immunosuppressive drug toxicity, hyperglycemia, hypoxia, unspecific inflammatory reactions, as well as allo- and autoimmune destruction. Therapeutic approaches to these damage mechanisms require early detection of islet injury, which is currently not feasible because of the lack of efficient markers. Based on the hypothesis of islet dissociation and release of islet cells into the circulation during islet injury, we designed a highly sensitive and specific molecular assay, able to detect two beta-cells per milliliter of venous blood by RT-PCR of insulin mRNA. We report that circulating beta-cells can be demonstrated up to 10 weeks after intraportal islet transplantation, as assessed after six islet grafts in four type 1 diabetic patients. Furthermore, our results suggest that the time during which circulating islet cells can be detected may depend on the graft environment and the immunosuppressive regimen. This test may allow better estimation of islet cell loss and identification of factors involved in islet graft injury. Topics: Adult; Aged; C-Peptide; Cell Count; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2002 |
Basal and postglucagon C-peptide levels in Ethiopians with diabetes.
To study basal C-peptide (BCP) and postglucagon C-peptide (PGCP) levels in Ethiopians with diabetes.. A total of 56 subjects with type 1 diabetes, 97 subjects with type 2 diabetes, and 50 control subjects were recruited from a hospital in Ethiopia. BCP was determined in all subjects and PGCP in 86 subjects.. Mean (+/- SEM) BCP, PGCP, and the increment after glucagon in type 1 diabetic subjects (0.14 +/- 0.04, 0.22 +/- 0.11, and 0.08 +/- 0.05 nmol/l, respectively) were lower (P < 0.001) than those in type 2 diabetic subjects (0.66 +/- 0.04, 1.25 +/- 0.10, and 0.56 +/- 0.06 nmol/l, respectively) or control subjects (0.54 +/- 0.04, 1.52 +/- 0.26, and 1.11 +/- 0.24 nmol/l, respectively). The mean BCP level was higher in type 2 diabetic subjects than control subjects (P=0.015), whereas the mean increment was lower (P=0.005). Insulin-treated type 2 diabetic subjects, compared with non-insulin-treated type 2 diabetic subjects, had lower mean BCP (0.55 +/- 0.08 nmol/l [n=37] vs. 0.73 +/- 0.04 [n=60], P=0.001), lower PGCP (0.97 +/- 0.20 nmol/l [n=18] vs. 1.40 +/- 0.11 [n=35], P=0.010), and a lower C-peptide increment (0.34 +/- 0.06 [n=18] vs. 0.67 +/- 0.07 nmol/l [n=35], P=0.003). In both the type 1 and type 2 diabetic groups, those with BCP levels <0.2 nmol/l had lower BMI than those with higher BCP levels (P=0.023 and P < 0.001, respectively).. Combined with clinical criteria, C-peptide levels are good discriminators between type 1 and type 2 diabetes in Ethiopians and may also be useful in identifying subjects with type 2 diabetes who require insulin therapy. There is a subgroup of type 2 diabetic subjects with features of type 1 diabetes. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Ethiopia; Female; Glucagon; Humans; Insulin; Male; Reference Values; Socioeconomic Factors | 2002 |
Genetic and environmental regulation of Na/K adenosine triphosphatase activity in diabetic patients.
Even if the pathogenesis of diabetic neuropathy is incompletely understood, an impaired Na/K adenosine triphosphatase (ATPase) activity has been involved in this pathogenesis. We previously showed that a restriction fragment length polymorphism (RFLP) of the ATP1-A1 gene encoding for the Na/K ATPase's alpha 1 isoform is associated with a low Na/K ATPase activity in the red blood cells (RBCs) of type 1 diabetic patients. We thus suggested that the presence of the variant of the ATP1A1 gene is a predisposing factor for diabetic neuropathy, with a 6.5% relative risk. Furthermore, there is experimental evidence showing that lack of C-peptide impairs Na/K ATPase activity, and that this activity is positively correlated with C-peptide level. The aim of this study was to evaluate the respective influence of genetic (ATP1-A1 polymorphism) and environmental (lack of C-peptide) factors on RBC's Na/K ATPase activity. Healthy and diabetic European and North African subjects were studied. North Africans were studied because there is a high prevalence and severity of neuropathy in this diabetic population, and ethnic differences in RBC's Na/K ATPase activity are described. In Europeans, Na/K ATPase activity was significantly lower in type 1 (285 +/- 8 nmol Pi/mg protein/h) than in type 2 diabetic patients (335 +/- 13 nmol Pi/mg protein/h) or healthy subjects (395 +/- 9 nmol Pi/mg protein/h). Among type 2 diabetic patients, there was a significant correlation between RBC's Na/K ATPase activity and fasting plasma C-peptide level (r = 0.32, P <.05). In North Africans, we confirm the ethnic RBC's Na/K ATPase activity decrease in healthy subjects (296 +/- 26 v 395 +/- 9 nmol Pi/mg protein/h, r < 0.05), as well as in type 1 diabetic patients (246 +/- 20 v 285 +/- 8 nmol Pi/mg protein/h; P <.05). However, there is no relationship between the ATP1A1 gene polymorphism and Na/K ATPase activity. ATP1A1 gene polymorphism could not explain the ethnic difference. We previously showed that Na/K ATPase activity is higher in type 1 diabetic patients without the restriction site on ATP1A1 than in those heterozygous for the restriction site. This fact was not observed in healthy subjects. In type 2 diabetic patients, association between ATP1A1 gene polymorphism and decreased enzyme activity was found only in patients with a low C-peptide level. Therefore, the ATP1-A1 gene polymorphism influences Na/K ATPase activity only in case of complete or partial C-peptide deficiency, as observed in Topics: Adult; Africa, Northern; Black People; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Environment; Erythrocytes; Europe; Female; Humans; Isoenzymes; Male; Middle Aged; Polymorphism, Genetic; Sodium-Potassium-Exchanging ATPase; White People | 2002 |
First human trial of pancreatic islet allo-transplantation in Korea--focus on re-transplantation.
Over the past 20 years, allo-transplantation of islet or whole pancreas for reaching and sustaining near-normoglycemia, as close as possible to the physiological model, have been undertaken. As previously known, even though islet transplantation is possible as a safe re-transplant, it is not well known whether re-transplantation of islets is suitable for patients who have lost the grafted islet function. We have performed a human islet allo-transplantation and re-transplantation on an IDDM patient for the first time in Asia and Korea. The recipient was a 32-year-old male and his insulin requirement was 75-85 U per day. After islet transplantation, the basal C-peptide increased from 0.6 to 2.1 ng/ml and insulin requirement decreased from 80 to 36 U per day, indicating that the grafted islets were functional. However, the grafted islets lost function 70 days after the transplantation. So, we performed re-transplantation of the islets. After the re-transplantation, the glucose profile became more stable and frequent episodes of severe hypoglycemia completely disappeared. His severe neuropathic pain improved dramatically and he could engage his ordinary daily life without any antineuropathic drugs. The success of this re-transplantation is one step closer to becoming a viable alternative for the millions of individuals who are suffering from diabetes. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Islets of Langerhans Transplantation; Korea; Male; Reoperation; Transplantation, Homologous | 2002 |
Relationship between diabetes and obesity 9 to 18 years after hemipancreatectomy and transplantation in donors and recipients.
Healthy human volunteers occasionally elect to undergo surgical removal of the distal half of their pancreas for donation to a relative with type 1 diabetes. This provides the unusual opportunity to study segments of the same pancreas in two markedly different environments, i.e., the normal one of the donor and the unusual one of the ectopically transplanted recipient who is receiving immunosuppressant drugs that can diminish insulin secretion and cause insulin resistance.. We studied eight donor/recipient pairs 9 to 18 years after the original surgery to assess the hypothesis that beta-cell mass is the primary determinant of glucose homeostasis. We measured levels of fasting glucose and hemoglobin A1c, intravenous glucose disappearance rates, acute insulin and C-peptide responses, and beta-cell secretory reserve.. Comparisons of the mean data between the two groups revealed no significant differences in fasting plasma glucose, hemoglobin A1c, fasting insulin or C-peptide, acute insulin or C-peptide responses to arginine and to glucose, or beta-cell secretory reserve. Eight patients were obese; this subgroup contained all patients who developed mild diabetes (four donors and two recipients).. The within-pairs metabolic outcomes support the primacy of pancreatic mass in determining glucose homeostasis, but the discordancy within pairs for developing postoperative diabetes implicates variables, especially obesity, as important secondary determinants in the risk of developing diabetes in donors and recipients. Our data suggest that obesity should be a contraindication to donation of pancreatic segments and that donors should assiduously avoid becoming obese. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male; Middle Aged; Obesity; Pancreas Transplantation; Pancreatectomy; Time Factors; Tissue Donors | 2002 |
Taq I polymorphism of the vitamin D receptor and risk of severe diabetic retinopathy.
Vitamin D, a molecule with antiproliferative, antiangiogenic, antioxidant and immunosuppressive effects, could play a role in the pathogenesis of severe diabetic retinopathy. We examined whether Taq I polymorphism of the vitamin D receptor is involved in the development of severe diabetic retinopathy.. 200 unrelated C-peptide-negative French Type I diabetic patients were randomly selected (male:female, 103:97, age 44.4 +/- 12.4 years, diabetes duration: 27.7 +/- 10.0 years, BMI: 24.3 +/- 3.4 kg/m(2), HbA(1c): 8.6 +/- 1.3 %). The Taq I site was analysed by PCR followed by digestion with Taq I enzyme. Diabetic retinopathy was assessed by retinal angiography and classified as presence (n = 101) or absence (n = 99) of severe (preproliferative or proliferative) diabetic retinopathy.. Frequency of wild-type genotype TT was lower in patients with severe diabetic retinopathy (n = 27) when compared with control subjects (n = 42, OR = 0.5, p = 0.028). Allele frequencies were not different between patients (T: n = 112 and t: n = 90) and control subjects (T: n = 128, and t: n = 70, p = 0.075). Global chi(2) (df = 2): p = 0.064. In subjects with diabetes duration of more than 25 years, TT was lower in severe diabetic retinopathy (n = 14) than control subjects (n = 18, OR = 0.3, p = 0.01). Allele frequencies were different between patients (T: n = 68 and t: n = 66) and control subjects (T: n = 52, OR = 0.5, and t: n = 26, OR = 1.9, p = 0.034). Global chi(2) (df = 2): p = 0.024. In subjects with HbA(1c) over 9 %, Tt was higher in patients (n = 28) than control subjects (n = 15, OR = 3.1, p = 0.019). Allele frequencies were not different between patients (T: n = 52 and t: n = 38) and control subjects (T: n = 57, and t: n = 29, p = 0.31). Global chi(2) (df = 2): p = 0.035.. In French Type I (insulin-dependent) diabetic patients, we demonstrate an association between TT form (VDR) and low risk for severe diabetic retinopathy, especially in patients with long duration, and between Tt variant and high risk for severe diabetic retinopathy in subjects with poor glycaemic control. Topics: Adult; Age of Onset; C-Peptide; Deoxyribonucleases, Type II Site-Specific; Diabetes Mellitus, Type 1; Diabetic Retinopathy; DNA; Female; Genotype; Humans; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Genetic; Receptors, Calcitriol; Reference Values; Restriction Mapping; Risk Factors | 2002 |
Clinical characteristics, GAD antibody (GADA) and change of C-peptide in Korean young age of onset diabetic patients.
To investigate the association of clinical and immunological markers with diabetes classification in newly diagnosed young diabetic patients at disease onset.. Eighty-two diabetic patients recruited within 1 year of onset (mean age 23.0 +/- 7.1, M:F = 46:36) were divided into three groups, namely: a low fasting C-peptide (FC) level at baseline group (the low FC group (n = 14, FC < 0.18 nmol/l)), an intermediate FC group (n = 29, 0.18 nmol/l < or = FC < 0.37 nmol/l), and a high FC group (n = 39, 0.37 nmol/l < or = FC). Patients were reclassified at follow-up (mean follow-up period 3.7 +/- 1.4 years) in the same manner as described above into low FC group (n = 31), intermediate FC group (n = 20), and high FC group (n = 31). The clinical characteristics and prevalence of GADA were compared.. Patients in the high FC group at baseline had a higher body mass index (BMI), a higher frequency of a family history of diabetes, a higher meal-stimulated C-peptide increment, a lower frequency of ketonuria, a lower frequency of history of diabetic ketoacidosis, and a lower frequency of insulin therapy at diagnosis than those in the low and intermediate FC groups at baseline. Insulin secretory capacity, which was represented by fasting C-peptide, was affected by BMI at diagnosis and the presence of GADA. All the patients of the low FC group on follow-up were finally classified as having Type 1 diabetes; moreover, the factors that determined the type of diabetes were lower BMI at onset, GADA positivity, insulin therapy, lower fasting C-peptide level and lower meal-stimulated C-peptide increment at initial admission.. Our study suggests that follow-up involving C-peptide and GADA measurements in combination with clinical characteristics is useful for discriminating between the types of diabetes in these groups. Topics: Adolescent; Adult; Age of Onset; Asian People; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glutamate Decarboxylase; Humans; Insulin; Korea; Male | 2002 |
Clinical characteristics of non-immune-mediated, idiopathic type 1 (type 1B) diabetes mellitus in Japanese children and adolescents.
To clarify the characteristics of idiopathic type 1 (type 1B) diabetes mellitus (DM), we compared the clinical features of immune-mediated type 1 (type 1A) DM and type 1B DM in 85 Japanese children and adolescents with DM. The prevalence of type 1B DM was 16.5%. The patients with type 1B DM were significantly younger at diagnosis and had a higher frequency of preceding viral infection before onset, compared to those with type 1A DM. They displayed more severe metabolic decompensation with a higher frequency of ketoacidosis at diagnosis than patients with type 1A DM. They had strong, HLA-defined genetic susceptibility, similar to that in type 1A DM. Some patients with type 1B DM exhibited a remarkably abrupt onset and rapid loss of beta-cell capacity. From these findings, it is considered that type 1B DM differs from type 1A DM with respect to age at onset and the trigger event, such as viral infection, leading to rapid destruction of beta-cells without autoimmunity in the etiology of the disease. Topics: Adolescent; Age of Onset; Bicarbonates; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Glycated Hemoglobin; HLA-DR Antigens; Humans; Japan; Male; Virus Diseases | 2002 |
Human islet retransplantation in a patient with type I diabetes.
Topics: Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Histocompatibility Testing; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Reoperation; Treatment Outcome | 2002 |
Transient neonatal diabetes mellitus, type 4, type 1 diabetes mellitus, or MODY: which disease is it, anyway?
A 30year-old Hispanic male who presented with transient neonatal diabetes mellitus at 4 months has been intensively studied with 12 islet-cell secretagogues from 4 months to 24 years. He was both ICA- and GAD-65-negative, but at 28 years was diagnosed with hypothyroidism due to positive thyroperoxidase antibodies. The course of his disease(s) and the various presentations of hyperglycemia are documented and illustrated by the responses in islet cell hormone secretion, namely, insulin, glucagon, and C-peptide. Insulin secretion gradually fell over 24 years, glucagon secretion persisted from infancy to 24 years but was only minimal during i.v. glucose at 24 years, and C-peptide secretion remained normal, although modest, throughout the 24 years. These data suggest that, despite changing presentations of diabetes mellitus over time, the islets continued to process proinsulin, although the patient required insulin therapy. Topics: Adult; Arginine; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Glucose Tolerance Test; Humans; Infant; Insulin; Insulin Secretion; Islets of Langerhans; Male; Tolbutamide | 2002 |
Latent autoimmune diabetes in adults.
Latent autoimmune diabetes in adults (LADA) is a special form of diabetes that is clinically similar to type 2 diabetes but with positivity for pancreatic autoantibodies. The frequency of LADA patients among all patients diagnosed as type 2 varies between 6-50% in various populations. The frequency is higher in younger age groups. It is clear, however, that the frequency of autoimmune diabetes among adults is underestimated. Clinical features such as age and severity of symptoms are of no help in identifying these patients. Body mass index and C peptide levels in the general population increase with age, and these parameters are of limited use in identifying LADA patients. Determination of autoantibodies is necessary in order to correctly classify the type of diabetes. Among antibodies, GADA is the most frequently occurring autoantibody, followed by ICA. The natural course of these patients shows that C peptide will decrease with time in parallel with the curve for C peptide in classical type 1 diabetic patients. Most of the LADA patients will require insulin within three years. Our recommendation is that all patients be tested for pancreatic islet autoantibodies at diagnosis of diabetes to enable correct diagnosis and to avoid future failure of hypoglycemic agents and risk of complications due to hyperglycemia. It is still unclear whether early treatment with insulin is beneficial for the remaining beta cells. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Follow-Up Studies; Glutamate Decarboxylase; Humans; Risk Factors | 2002 |
Human islet allotransplantation with Basiliximab in type I diabetic patients with end-stage renal failure.
Topics: Antibodies, Monoclonal; Basiliximab; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glycated Hemoglobin; Graft Survival; Humans; Immunosuppressive Agents; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Recombinant Fusion Proteins; Reoperation; Retrospective Studies; Time Factors; Transplantation, Homologous | 2002 |
Pancreatic islet transplantation using the nonhuman primate (rhesus) model predicts that the portal vein is superior to the celiac artery as the islet infusion site.
We've established a nonhuman primate islet allotransplant model to address questions such as whether transplanting islets into the gut's arterial system would more safely and as effectively support long-term islet allograft survival compared with the traditional portal vein approach. We reasoned that islets make up <2% of pancreatic cell mass but consume an estimated 20% of arterial blood flow, suggesting an advantage for the arterial site. Access to the arterial system is also easier and safer than the portal system. Pancreatectomized rhesus macaques were transplanted with allogeneic islets infused into either the portal vein (n = 6) or the celiac artery (n = 4). To prevent rejection, primates were given daclizumab, tacrolimus, and rapamycin. In five of six portal vein experiments, animals achieved normoglycemia without exogenous insulin. In contrast, none of the animals given intra-arterial islets showed even transient insulin independence (P = 0.048). Two of the latter animals received a second islet transplant, this time to the portal system, and both achieved insulin independence. Thus, intraportal islet transplantation under conventional immunosuppression is feasible in primates and can result in long-term insulin independence when adequate immunosuppression is maintained. Arterial islet injection, however, does not appear to be a viable islet transplantation technique. Topics: Animals; Arginine; Blood Glucose; C-Peptide; Celiac Artery; Diabetes Mellitus, Type 1; Graft Rejection; Graft Survival; Islets of Langerhans; Islets of Langerhans Transplantation; Macaca mulatta; Organ Size; Portal Vein; Transplantation, Homologous | 2002 |
Human C-peptide dose dependently prevents early neuropathy in the BB/Wor-rat.
In order to explore the neuroprotective and cross-species activities of C-peptide on type 1 diabetic neuropathy, spontaneously diabetic BB/W-rats were given increasing doses of human recombinant C-peptide (hrC-peptide). Diabetic rats received 10, 100, 500, or 1000 microg of hrC-peptide/kg body weight/day from onset of diabetes. After 2 months of hrC-peptide administration, 100 microg and greater doses completely prevented the nerve conduction defect, which was associated with a significant but incomplete prevention of neural Na+/K+-ATPase activity in diabetic rats with 500 microg or greater C-peptide replacement. Increasing doses of hrC-peptide showed increasing prevention of early structural abnormalities such as paranodal swelling and axonal degeneration and an increasing frequency of regenerating sural nerve fibers. We conclude that hrC-peptide exerts a dose dependent protection on type 1 diabetic neuropathy in rats and that this effect is probably mediated by the partially conserved sequence of the active C-terminal pentapeptide. Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Dose-Response Relationship, Drug; Humans; Insulin; Kinetics; Male; Nerve Fibers; Neural Conduction; Rats; Rats, Inbred BB; Recombinant Proteins; Sodium-Potassium-Exchanging ATPase; Sural Nerve | 2001 |
Classifying diabetes according to the new WHO clinical stages.
To test the usefulness of the new WHO criteria for clinical staging of diabetes in the characterization of 1977 diabetic patients.. The following clinical stages were used: patients on diet and/or oral antidiabetic agents 2 years after diagnosis were considered as non-insulin requiring (NIR; n = 711) and patients who required insulin therapy after 1 year as insulin requiring for control (IRC; n = 543). Patients who because of deteriorating hyperglycemia within 1 year required insulin therapy were considered as insulin requiring for survival (IRS; n = 743).. The NIR patients had the highest age at onset (52 +/- 12 years; mean +/- SD), BMI (29.3 +/- 5.2 kg/m2) and C-peptide concentrations (median 0.98 nmol/l; interquartile range 0.72-1.31 nmol/l) but the lowest frequency of GAD antibodies (5.5%) compared to the IRC and IRS groups. The IRC group had a high age at onset (49 +/- 13 years), BMI (28.0 +/- 4.8 kg/m2), frequency of GAD antibodies (16.8%), intermediate C-peptide concentrations (0.56 nmol/l, interquartile range 0.28 +/- 0.94), and the highest prevalence of nephropathy (31.5%) and neuropathy (68.1%). The IRS group had the lowest age at onset (23 +/- 15 years), BMI (24.2 +/- 3.4 kg/m2), C-peptide concentrations (0.05 nmol/l, interquartile range below detection limit 0.01) and highest frequency of GAD antibodies (44.5%). Retinopathy was more common in IRS than in IRC patients (62.1 vs. 43.9%;p < 0.001).. The new WHO criteria seem to discriminate three distinct subgroups and thus provide a useful tool for clinical staging. The IRC patients seem to have a more severe disease than the IRS patients, which has not been clearly acknowledged in the etiological classification. However, because of the cross-sectional nature of these data, they need to be confirmed in a prospective study with defined cut-off limits for when insulin should be initiated. Topics: Aged; Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Guidelines as Topic; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Sweden; World Health Organization | 2001 |
Possible human leukocyte antigen-mediated genetic interaction between type 1 and type 2 Diabetes.
We assessed the prevalence of families with both type 1 and type 2 diabetes in Finland; and we studied, in patients with type 2 diabetes, the association between a family history of type 1 diabetes, glutamic acid decarboxylase (GAD) antibodies (GADab), and type 1 diabetes-associated human leukocyte antigen (HLA) DQB1-genotypes. Further, in mixed type 1/type 2 diabetes families, we investigated whether sharing an HLA haplotype with a family member with type 1 diabetes influenced the manifestation of type 2 diabetes. Among 695 families ascertained through the presence of more than 1 patient with type 2 diabetes, 100 (14%) also had members with type 1 diabetes. Type 2 diabetic patients from the mixed families had, more often, GADab (18% vs. 8%, P < 0.0001) and DQB1*0302/X genotype (25% vs. 12%, P = 0.005) than patients from families with only type 2 diabetes; but they had a lower frequency of DQB1*02/0302 genotype, compared with adult-onset type 1 patients (4% vs. 27%, P < 0.0001). In the mixed families, the insulin response to oral glucose load was impaired in patients who had HLA class II risk haplotypes, either DR3(17)-DQA1*0501-DQB1*02 or DR4*0401/4-DQA1*0301-DQB1*0302, compared with patients without such haplotypes (P = 0.016). This finding was independent of the presence of GADab. We conclude that type 1 and type 2 diabetes cluster in the same families. A shared genetic background with a patient with type 1 diabetes predisposes type 2 diabetic patients both to autoantibody positivity and, irrespective of antibody positivity, to impaired insulin secretion. The findings support a possible genetic interaction between type 1 and type 2 diabetes mediated by the HLA locus. Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Finland; Genotype; Glucose Tolerance Test; Glutamate Decarboxylase; HLA-D Antigens; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR3 Antigen; HLA-DR4 Antigen; Humans; Insulin; Male; Middle Aged | 2001 |
Successful long-term kidney-pancreas transplants regardless of C-peptide status or race.
We have previously shown that our patient population of 60% minority races has end-stage renal disease primarily as a result of diabetes mellitus and hypertension. It therefore was logical to explore the restoration of normal insulin production and renal function by simultaneous pancreas-kidney (SPK) transplantation, without regard to race. This study represents new analyses integrating race with C-peptide status and reports the outcome of 136 SPK transplantations performed over the last 10 years.. Of the 49 African-Americans with diabetes mellitus and end-stage renal disease, 60% were type I and 40% were type II, based on C-peptide levels. In comparison, only 16% of Caucasians were type II. The average age at onset of diabetes mellitus was 15.7 years for type I compared with 20.7 years for type II (P>0.05). The actuarial 10-year survival rates for the 136 SPKs were 91.79% (patient), 85.07% (pancreas), and 83.58% (kidney). The type I and type II survival rates were similar in the two diabetic groups.. The data strongly suggest that pretransplant C-peptide status does not influence the outcome of SPK transplantation in patients with renal failure from diabetes mellitus. SPK transplants should be offered to all suitable diabetic patients with renal failure regardless of C-peptide status or race. Topics: Black People; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Graft Survival; Humans; Kidney Failure, Chronic; Kidney Transplantation; Pancreas Transplantation; Time Factors | 2001 |
Rapid loss of insulin secretion in a patient with fulminant type 1 diabetes mellitus and carbamazepine hypersensitivity syndrome.
Topics: Aged; Analgesics, Non-Narcotic; Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; C-Peptide; Carbamazepine; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Drug Eruptions; Female; Herpesviridae Infections; Herpesvirus 6, Human; Humans; Insulin; Insulin Secretion; Syndrome | 2001 |
Effect of glucagon-like peptide-1(7-36)-amide on initial splanchnic glucose uptake and insulin action in humans with type 1 diabetes.
In vitro studies indicate that glucagon-like peptide-1(7-36)-amide (GLP-1) can enhance hepatic glucose uptake. To determine whether GLP-1 increases splanchnic glucose uptake in humans, we studied seven subjects with type 1 diabetes on two occasions. On both occasions, glucose was maintained at approximately 5.5 mmo/l during the night using a variable insulin infusion. On the morning of the study, a somatostatin, glucagon, and growth hormone infusion was started to maintain basal hormone levels. Glucose (containing [3H]glucose) was infused via an intraduodenal tube at a rate of 20 micromol.kg(-1).min(-1). Insulin concentrations were increased to approximately 500 pmol/l while glucose was clamped at approximately 8.8 mmol/l for the next 4 h by means of a variable intravenous glucose infusion labeled with [6,6-2H2]glucose. Surprisingly, the systemic appearance of intraduodenally infused glucose was higher (P = 0.01) during GLP-1 infusion than saline infusion, indicating a lower (P < 0.05) rate of initial splanchnic glucose uptake (1.4 +/- 1.5 vs. 4.8 +/- 0.8 micromol.kg(-1).min(-1)). On the other hand, flux through the hepatic uridine-diphosphate- glucose pool did not differ between study days (14.2 +/- 5.5 vs. 13.0 +/- 4.2 micromol.kg(-1).min(-1)), implying equivalent rates of glycogen synthesis. GLP-1 also impaired (P < 0.05) insulin-induced suppression of endogenous glucose production (6.9 +/- 2.9 vs. 1.3 +/- 1.4 micromol.kg(-1).min(-1)), but caused a time-dependent increase (P < 0.01) in glucose disappearance (93.7 +/- 10.0 vs. 69.3 +/- 6.3 micromol.kg(-1).min(-1); P < 0.01) that was evident only during the final hour of study. We conclude that in the presence of hyperglycemia, hyperinsulinemia, and enterally delivered glucose, GLP-1 increases total body but not splanchnic glucose uptake in humans with type 1 diabetes. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Duodenum; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Glucose; Human Growth Hormone; Hydrocortisone; Hypoglycemic Agents; Insulin; Intubation; Osmolar Concentration; Peptide Fragments; Viscera | 2001 |
Effects of short-term improvement of insulin treatment and glycemia on hepatic glycogen metabolism in type 1 diabetes.
Insufficiently treated type 1 diabetic patients exhibit inappropriate postprandial hyperglycemia and reduction in liver glycogen stores. To examine the effect of acute improvement of metabolic control on hepatic glycogen metabolism, lean young type 1 diabetic (HbA1c 8.8 +/- 0.3%) and matched nondiabetic subjects (HbA1c 5.4 +/- 0.1%) were studied during the course of a day with three isocaloric mixed meals. Hepatic glycogen concentrations were determined noninvasively using in vivo 13C nuclear magnetic resonance spectroscopy. Rates of net glycogen synthesis and breakdown were calculated from linear regression of the glycogen concentration time curves from 7:30-10:30 P.M. and from 10:30 P.M. to 8:00 A.M., respectively. The mean plasma glucose concentration was approximately 2.4-fold higher in diabetic than in nondiabetic subjects (13.6 +/- 0.4 vs. 5.8 +/- 0.1 mmol/l, P < 0.001). Rates of net glycogen synthesis and net glycogen breakdown were reduced by approximately 74% (0.11 +/- 0.02 vs. 0.43 +/- 0.04 mmol/l liver/min, P < 0.001) and by approximately 47% (0.10 +/- 0.01 vs. 0.19 +/- 0.01 mmol/l liver/min, P < 0.001) in diabetic patients, respectively. During short-term (24-h) intensified insulin treatment, the mean plasma glucose level was not different between diabetic and nondiabetic subjects (6.4 +/- 0.1 mmol/l). Net glycogen synthesis and breakdown increased by approximately 92% (0.23 +/- 0.04 mmol/l liver/min, P = 0.017) and by approximately 40% (0.14 approximately 0.01 mmol/l liver/min, P = 0.011), respectively. In conclusion, poorly controlled type 1 diabetic patients present with marked reduction in both hepatic glycogen synthesis and breakdown. Both defects in glycogen metabolism are improved but not normalized by short-term restoration of insulinemia and glycemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glycogen; Humans; Hypoglycemic Agents; Insulin; Liver; Male; Time Factors | 2001 |
Clinical outcomes and insulin secretion after islet transplantation with the Edmonton protocol.
Islet transplantation offers the prospect of good glycemic control without major surgical risks. After our initial report of successful islet transplantation, we now provide further data on 12 type 1 diabetic patients with brittle diabetes or problems with hypoglycemia previous to 1 November 2000. Details of metabolic control, acute complications associated with islet transplantation, and long-term complications related to immunosuppression therapy and diabetes were noted. Insulin secretion, both acute and over 30 min, was determined after intravenous glucose tolerance tests (IVGTTs). The median follow-up was 10.2 months (CI 6.5-17.4), and the longest was 20 months. Glucose control was stable, with pretransplant fasting and meal tolerance-stimulated glucose levels of 12.5+/-1.9 and 20.0+/-2.7 mmol/l, respectively, but decreased significantly, with posttransplant levels of 6.3+/-0.3 and 7.5+/-0.6 mmol/l, respectively (P < 0.006). All patients have sustained insulin production, as evidenced by the most current baseline C-peptide levels 0.66+/-0.06 nmol/l, increasing to 1.29+/-0.25 nmol/l 90 min after the meal-tolerance test. The mean HbA1c level decreased from 8.3+/-0.5% to the current level of 5.8+/-0.1% (P < 0.001). Presently, four patients have normal glucose tolerance, five have impaired glucose tolerance, and three have post-islet transplant diabetes (two of whom need oral hypoglycemic agents and low-dose insulin (<10 U/day). Three patients had a temporary increase in their liver-function tests. One patient had a thrombosis of a peripheral branch of the right portal vein, and two of the early patients had bleeding from the hepatic needle puncture site; but these technical problems were resolved. Two patients had transient vitreous hemorrhages. The two patients with elevated creatinine levels pretransplant had a significant increase in serum creatinine in the long term, although the mean serum creatinine of the group was unchanged. The cholesterol increased in five patients, and lipid-lowering therapy was required for three patients. No patient has developed cytomegalovirus infection or disease, posttransplant lymphoproliferative disorder, malignancies, or serious infection to date. None of the patients have been sensitized to donor antigen. In 11 of the 12 patients, insulin independence was achieved after 9,000 islet equivalents (IEs) per kilogram were transplanted. The acute insulin response and the insulin area under the curve (AUC) after IVGTT were Topics: Adult; Blood Glucose; C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Male; Postoperative Complications; Postoperative Period; Treatment Outcome | 2001 |
Partial remission phase and metabolic control in type 1 diabetes mellitus in children and adolescents.
A better understanding of the remission phase, while residual beta-cell function is still present in recently diagnosed type 1 (insulin dependent) diabetes mellitus (IDDM), is very important because of the potential for pharmacological intervention to preserve this function. To evaluate the natural course and characteristics of the remission phase in children and adolescents with IDDM, a retrospective study was performed on patients diagnosed with IDDM under the age of 18 years during the years 1991-1998. Sixty-two patients whose medical records were available were included in the study. Data were collected by reviewing the hospital records of patients from the time of diagnosis through the first 24 months after diagnosis. The duration of symptoms and history of infection prior to presentation, diabetic ketoacidosis (DKA) at diagnosis, length of hospitalization, initial glucose level, basal C-peptide levels at diagnosis, daily insulin requirements per kg body weight and HbA1c at diagnosis and at each visit were recorded. Thirty-five patients (56.5%) entered partial remission. We observed similar remission rates in those aged <10 and > or =10 years at diagnosis and in boys and girls. History of infection and presentation with DKA were associated with a lower rate of remission (p<0.001, p<0.0001, respectively) and were more commonly observed under the age of 10 years (p<0.0001, p<0.0001, respectively). The average insulin requirements per kg body weight calculated at diagnosis decreased with increasing age (r = -0.31, p = 0.012). The length of time until remission was 1.36+/-1.03 (mean +/- SD) months and positively correlated with insulin requirements at discharge from the hospital (r = 0.63, p<0.0001). Mean duration of remission was 11.67+/-5.82 months and was much longer in boys than girls (p<0.05). Six patients, all boys, entered total remission for 3.80+/-3.73 months. HbA1c concentrations in the first year of the disease were significantly lower in patients who underwent a remission phase (7.31+/-1.24% vs. 8.24+/-1.47%, p <0.05). However, this difference was not observed during the second year of the disease. In conclusion, history of infection prior to presentation and DKA at diagnosis were associated with young age and were the most important factors negatively influencing the remission rate in newly diagnosed IDDM patients. Topics: Adolescent; Aging; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Infections; Insulin; Islets of Langerhans; Length of Stay; Male; Puberty; Remission Induction; Retrospective Studies | 2001 |
Progression of cardiac dysfunction in a case of mitochondrial diabetes: a case report.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Disease Progression; DNA, Mitochondrial; Echocardiography; Glycated Hemoglobin; Humans; Male; Mitochondrial Myopathies; Point Mutation; Ventricular Dysfunction, Left | 2001 |
Renal handling of zinc in insulin-dependent diabetes mellitus patients.
Hyperzincuria is a common feature in diabetic patients, which is still not understood. Based on the above consideration, the aim of the present study was to investigate the renal handling of zinc in insulin-dependent diabetes mellitus (IDDM) patients. The glomerular filtration rate, urinary zinc excretion, zinc clearance, zinc clearance/creatinine clearance ratio, zinc tubular reabsorption, glycosuria, plasma glucose, C-peptide, glucagon, and cortisol were investigated in 10 normal individuals (Group C1 and Group C2, respectively) and 10 IDDM patients (Group E1: hyperglycemic and glycosuric and Group E2: normoglycemic and aglycosuric) during placebo or venous zinc tolerance test. The results showed that urinary zinc excretion and renal zinc clearance were increased after zinc injection in normal individuals (Group C2) and IDDM patients (Groups E1 and E2) when compared with normal individuals-placebo (Group C1). However, these renal parameters were statistically more significant in the hyperglycemic and glycosuric diabetics (Group E1). Because patients in Group E1 had the lowest plasma C-peptide levels and showed a strong negative correlation between CZn++/Ccr ratio and this hormone, we suggest that in this setting insulin inhibits urinary zinc excretion. Topics: Adult; Blood Glucose; C-Peptide; Case-Control Studies; Creatinine; Diabetes Mellitus, Type 1; Female; Glomerular Filtration Rate; Glucagon; Glycosuria; Humans; Hydrocortisone; Kidney; Kidney Tubules; Male; Zinc | 2001 |
Establishing surveillance for diabetes in American Indian youth.
To determine prevalence estimates in order to monitor diabetes, particularly type 2 diabetes, in American Indian youth.. To explore the feasibility of developing a case definition using information from primary care records, all youth aged <20 years with an outpatient visit or hospitalization for diabetes were identified from the Billings Area Indian Health Service database in Montana and Wyoming from 1997 to 1999, and the medical records were reviewed. Classification for probable type 1 diabetes was based on age < or =5 years, weight per age < or =15th percentile at diagnosis, or positive results of islet cell antibody test. Classification for probable type 2 diabetes was based on weight per age > or =85th percentile or presence of acanthosis nigricans at diagnosis, elevated C-peptide or insulin, family history for type 2 diabetes, or use of oral hypoglycemic agents with or without insulin or absence of current treatment 1 year after diagnosis.. A total of 52 case subjects with diabetes were identified, 3 of whom had diabetes secondary to other conditions. Of the remaining 49 case subjects, 25 (51%) were categorized as having probable type 2 diabetes, 14 (29%) as having probable type 1 diabetes, and 10 (20%) could not be categorized because of missing or negative information. Prevalence estimates for diabetes of all types, type 1 diabetes, and type 2 diabetes were 2.3, 0.6, and 1.1, respectively, per 1,000 youth aged <20 years.. Our definitions may be useful for surveillance in primary care settings until further studies develop feasible case definitions for monitoring trends in diabetes among youth. Topics: Acanthosis Nigricans; Adolescent; Adult; Autoantibodies; Body Weight; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Guidelines as Topic; Humans; Indians, North American; Inpatients; Insulin; Islets of Langerhans; Medical Records; Montana; Outpatients; Retrospective Studies; Wyoming | 2001 |
Islet cell autoimmunity in youth onset diabetes mellitus in Northern India.
We characterised a consecutive cohort of 132 youth onset diabetic individuals (age at onset<30 years, mean duration of disease 5.5+/-6.0 years) from North India, by serological determination of the determination of the islet cell autoantibodies, GAD(65) and IA2, and clinically for coexisting autoimmune thyroid disease, malnutrition and pancreatic calcification. Five types of diabetes were delineated: Type 1 (37%), ketosis resistant (32%), Type 2 (13%), fibrocalculous pancreatopathy (11%) and autoimmune polyglandular syndrome (7%). C-peptide response to glucagon was assessed in a representative subset of 50 patients with Type 1, ketosis resistant, and autoimmune polyglandular syndrome. A total of 22.4% of Type 1 and 30% of autoimmune polyglandular syndrome subjects showed both GAD(65) plus IA-2 autoantibody positivity, significantly more than the 4.7% positivity shown by the ketosis resistant type. However, GAD(65) antibody positivity alone was seen in 38% of ketosis resistant subjects which was significantly more than the 14.2 and 10% positivity seen in Type 1 and autoimmune polyglandular groups, respectively. The fibrocalculous pancreatopathy group showed GAD(65) plus IA-2 autoantibody positivity in 14.2% and GAD(65) autoantibody alone positivity in 7.1%. 26 and 60%, respectively, of the Type 1 and autoimmune polyglandular syndrome groups had thyroid microsomal autoantibody positivity. Type 1 showed significantly less C-peptide response to glucagon when compared to the ketosis resistant and autoimmune polyglandular syndrome groups. The controls and Type 2 diabetic individuals tested negative for islet cell autoimmunity markers. These findings demonstrate a role of islet cell autoimmunity in the pathogenesis of four out of the five clinical types of youth onset diabetes seen in North India. Topics: Adolescent; Adult; Age of Onset; Asian People; Autoantibodies; C-Peptide; Cohort Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Glutamate Decarboxylase; Humans; India; Islets of Langerhans; Isoenzymes; Male; Pancreatic Diseases; Thyroid Gland | 2001 |
No influence of C-peptide, insulin, and glucagon on blood viscosity in vitro in healthy humans and patients with diabetes mellitus.
The influence of the hormones most involved in glucose homeostasis, C-peptide, insulin and glucagon on blood viscosity was tested in vitro. Whole blood (adjusted to haematocrit 45%) from healthy volunteers (n=24) and patients with diabetes mellitus (n=17) was incubated with 10(-7)-10(-10) M C-peptide, insulin or glucagon. None of these peptide hormones, neither at physiological nor at supraphysiological levels, had an influence on high (94.5 s(-1)) or low (0.1 s(-1)) shear rate viscosity. The small group of diabetic patients had a higher plasma viscosity and increased blood viscosity at 94.5 s(-1), which is in agreement with earlier studies, but decreased viscosity at low shear rate. We conclude that C-peptide, insulin and glucagon have no direct effect on blood viscosity in vitro. It is, therefore, unlikely that microvascular disturbances seen with either deficiency or excess of these hormones is due to haemorheological factors. Topics: Adult; Aged; Blood Proteins; Blood Viscosity; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Dose-Response Relationship, Drug; Erythrocyte Indices; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Male; Middle Aged | 2001 |
Erectile dysfunction and lower androgenicity in type 1 diabetic patients.
To analyse the clinical characteristics and relevant hormonal profile in type 1 diabetic patients with and without ED.. Fifty one type 1 diabetic patients were studied. ED was assessed by direct interview. Chronic diabetic complications, smoking and alcohol status as well as current use of medications were recorded. Hormonal profile consisted of plasma LH, FSH, prolactin, androstenedione (Delta(4)), dehydroepiandrosterone (DHEA), DHEA-sulfate (DHEA-S), free testosterone (FT), estradiol (E(2)), sex hormone binding globulin (SHBG), dihydrotestosterone (DHT), cortisol, TSH and free thyroxine (FT(4)).. ED was present in 24 patients (47%) (group 1), who were older (P<0.001), had a longer diabetes duration (P<0.001) and a higher systolic blood pressure (P=0.017) when compared to the subjects who did not complain (group 2). ED was positively correlated to all diabetes-related complications (P<0.02). Antidepressive drug(s) were more frequent in group 1 (P=0.007), as well as prokinetics (P=0.043) and ACE-inhibitors (P=0.010). HbA(1)c was comparable. Patients with ED had lower levels of Delta(4) (P=0.003), DHEA (P<0.001), DHEA-S (P=0.002), FT (P=0.08) while SHBG (P=0.010) and LH (P=0.022) were higher compared to group 2. Multiple logistic regression analysis showed an independent association of ED with Delta(4) (P=0.016), DHEA-S (P=0.037), SHBG (P=0.001) and insulin dose (P=0.025). There was no significant difference for all other measured hormones.. ED is impressively prevalent in type 1 diabetes and is associated with age, diabetes duration, chronic complications and decreased androgens. Topics: Age Factors; Alcohol Drinking; Androgens; Blood Pressure; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Neuropathies; Diabetic Retinopathy; Erectile Dysfunction; Estradiol; Follicle Stimulating Hormone; Humans; Hydrocortisone; Hypertension; Luteinizing Hormone; Male; Middle Aged; Prolactin; Smoking | 2001 |
Heterogeneity of fetal growth in type 1 diabetic pregnancy.
To investigate the frequency of macrosomia in an homogeneous cohort of type 1 diabetic mothers and to analyze the influence of maternal factors and glycemic control on the incidence of fetal macrosomia.. Fifty-five consecutive type 1 diabetic first-pregnancies were prospectively studied. Macrosomia was defined by a ponderal index above the 90(th) percentile. Venous cord blood levels of insulin, C peptide and leptin were measured at delivery. The influence of HbA1c levels and other maternal variables on the occurrence of macrosomia and on the ponderal index was assessed using a stepwise regression logistic model.. The mean (+/- SD) birth weight was 3482 (+/- 497) g at 37.4 +/- 1.0 weeks gestation. Macrosomia occurred in 29 cases (53.7%). Fetal insulin, C peptide and leptin levels were significantly higher in macrosomic than in non macrosomic infants. Maternal age, duration of diabetes, pregravid body mass index, parity, weight gain during pregnancy, presence of a microangiopathy, nephropathy, smoking habits, gestational hypertension or preeclampsia, and HbA1c levels throughout pregnancy did not differed between mothers of macrosomic and non macrosomic infants. In the stepwise analysis none of these covariates was explanatory of the ponderal index.. The frequency of macrosomia remains very high in infants of type 1 diabetic mothers despite a reasonable degree of glycemic control. The variability of the fetal growth response to mild hyperglycemia prompts for the identification of other factors involved in the modulation of fetal growth. Topics: Adult; Birth Weight; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Embryonic and Fetal Development; Female; Fetal Macrosomia; Gestational Age; Glycated Hemoglobin; Humans; Hypoglycemia; Infant, Newborn; Insulin; Leptin; Maternal Age; Placenta; Pregnancy; Pregnancy in Diabetics; Prospective Studies; Reference Values | 2001 |
Type I diabetes mellitus does not alter initial splanchnic glucose extraction or hepatic UDP-glucose flux during enteral glucose administration.
Our aim was to determine whether an alteration in splanchnic glucose metabolism could contribute to postprandial hyperglycaemia in people with Type I (insulin-dependent) diabetes mellitus.. Splanchnic glucose extraction, hepatic glycogen synthesis and endogenous glucose production were compared in 8 Type I diabetic patients and in 11 control subjects. Endogenous hormone secretion was inhibited with somatostatin while insulin (approximately 550 pmol/l) and glucagon (approximately 130 ng/l) concentrations were matched with exogenous hormone infusions. Glucose containing [3-3H] glucose was infused into the duodenum at a rate of 20 micromol.kg(-1).min(-1). Plasma glucose concentrations were maintained at about 8.5 mmol/l in both groups by means of a separate variable intravenous glucose infusion.. Initial splanchnic glucose uptake, calculated by subtracting the systemic rate of appearance of [3-3H] glucose from the rate of infusion of [3-3H] glucose into the duodenum, did not differ in the diabetic and non-diabetic patients (4.1 +/- 0.8 vs 3.0 +/- 1.0 micromol/kg/min). In addition, hepatic glycogen synthesis, measured using the acetaminophen glucuronide method did not differ (10.7 +/- 2.4 vs 10.1 +/- 2.7 micromol.kg(-1).min(-1)). On the other hand, suppression of endogenous glucose production, measured by an intravenous infusion of [6,6-2H2] glucose, was greater (p < 0.05) in the diabetic than in the non-diabetic subjects (1.7 +/- 1.6 vs 5.8 +/- 1.9 micromol.kg(-1).min(-1)).. When glucose, insulin and glucagon concentrations are matched in individuals with relatively good chronic glycaemic control, Type I diabetes does not alter initial splanchnic glucose uptake of enterally delivered glucose or hepatic glycogen synthesis. Alterations in splanchnic glucose metabolism are not likely to contribute to postprandial hyperglycaemia in people with well controlled Type I diabetes. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Duodenum; Glucose; Hormones; Humans; Injections; Injections, Intravenous; Insulin; Liver; Reference Values; Uridine Diphosphate; Viscera | 2001 |
High levels of antigen-specific islet antibodies predict future beta-cell failure in patients with onset of diabetes in adult age.
It is unclear whether high levels of antigen-specific islet antibodies [GADA (glutamic acid decarboxylase 65 antibodies) and IA2-ab (protein tyrosine phosphatase-like protein antibodies)] predict beta-cell failure in patients with onset of diabetes in adult age. Therefore, GADA and IA2-ab levels at the diagnosis of diabetes were related to fasting plasma C-peptide levels 5 yr later in 148 patients with diabetes onset in adult age (age at onset, 20-77 yr; median, 57 yr). Classical islet cell antibodies (ICA) were also determined. Complete beta-cell failure (undetectable fasting plasma C-peptide) was only present in 4 patients at diagnosis of diabetes, but in 21 patients 5 yr thereafter. At diagnosis, ICA were detected in 20 of 21 (95%) patients with beta-cell failure after 5 yr and in only 7 of 127 (5%) without, whereas GADA and/or IA2-ab (>97.5 percentile of healthy controls) were detected in all 21 (100%) with but also in 23 of 127 (18%) patients without beta-cell failure after 5 yr. Thus, ICA had a higher positive predictive value (74%) than GADA and/or IA2-ab (47%; P < 0.05). With high cutoff values for GADA and IA2-ab, however, GADA and/or IA2-ab were detected in 19 of 21 (90%) patients with beta-cell failure vs. only in 5 of 127 (4%) without, giving a positive predictive value of 79%. Slightly elevated GADA levels in IA2-ab-negative patients were associated with progressive but not complete beta-cell failure within the study period. Hence, high GADA and/or IA2-ab levels predict a future complete beta-cell failure, whereas low GADA levels predict slowly progressive beta-cell insufficiency. Topics: Adult; Aged; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Glucose Tolerance Test; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Islets of Langerhans; Kinetics; Male; Membrane Proteins; Middle Aged; Nerve Tissue Proteins; Prospective Studies; Receptor-Like Protein Tyrosine Phosphatases, Class 8; ROC Curve; Sensitivity and Specificity | 2001 |
Complete protection of islets against allorejection and autoimmunity by a simple barium-alginate membrane.
We describe a new technique for microencapsulation with high-mannuronic acid (high-M) alginate crosslinked with BaCl(2) without a traditional permselective component, which allows the production of biocompatible capsules that allow prolonged survival of syngeneic and allogeneic transplanted islets in diabetic BALB/c and NOD mice for >350 days. The normalization of the glycemia in the transplanted mice was associated with normal glucose profiles in response to intravenous glucose tolerance tests. After explantation of the capsules, all mice became hyperglycemic, demonstrating the efficacy of the encapsulated islets. The retrieved capsules were free of cellular overgrowth and islets responded to glucose stimulation with a 5- to 10-fold increase of insulin secretion. Transfer of splenocytes isolated from transplanted NOD mice to NOD/SCID mice adoptively transferred diabetes, indicating that NOD recipients maintained islet-specific autoimmunity. In conclusion, we have developed a simple technique for microencapsulation that prolongs islet survival without immunosuppression, providing complete protection against allorejection and the recurrence of autoimmune diabetes. Topics: Alginates; Animals; Autoimmunity; Biocompatible Materials; Blood Glucose; C-Peptide; Capsules; Coculture Techniques; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Glucuronic Acid; Graft Rejection; Graft Survival; Hexuronic Acids; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; Mice, Inbred Strains; Spleen; Subrenal Capsule Assay; T-Lymphocytes; Time Factors; Transplantation, Homologous; Transplantation, Isogeneic | 2001 |
Titre and combination of ICA and autoantibodies to glutamic acid decarboxylase discriminate two clinically distinct types of latent autoimmune diabetes in adults (LADA).
ABSTRACT AIMS/HYPOTHESIS: This study aimed to define the immunological parameters which could be used to identify patients with the distinct metabolic features of adult latent autoimmune diabetes.. Sera of 312 patients with short-term diabetes (duration < 5 years) over 35 years of age at diagnosis were screened for ICA, GAD- and IA2-Ab by antibody assays validated in workshops. The antibody status was correlated with age, BMI, residual beta-cell function, measured by fasting C-peptide, onset of diabetes-related complications and markers of the metabolic syndrome (hypertension and hyperlipidaemia).. A total of 51 antibody positive patients were identified. These patients had lower fasting C-peptide and less neuropathy and hypertension compared with matched antibody-negative patients. However, only patients with two or more antibodies had reduced residual beta-cell function compared with antibody-negative or single antibody-positive (ICA or GAD-Ab only) patients. Patients with two or more antibodies were also leaner and had diabetes-related complications or hypertension less frequently than single antibody-positive or antibody negative-patients. IA2 antibody status did not substantially contribute to the diagnosis or differentiation of LADA patients.. We concluded that the combination of ICA and GAD antibodies and high titre of GAD antibodies are characteristic of patients with insulin deficiency with the clinical features of Type I (insulin-dependent) diabetes mellitus (LADA-type 1). Single antibody positivity and low titre antibodies are markers for LADA-type 2 associated with the clinical and metabolic phenotype of Type II (non-insulin-dependent) diabetes patients. Topics: Adult; Autoantibodies; Autoimmune Diseases; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Glutamate Decarboxylase; Humans; Islets of Langerhans; Middle Aged | 2001 |
Influence of age on clinical and immunological characteristics of newly diagnosed type 1 diabetic patients.
The aim of this study was to analyse the immunological and clinical characteristics of a group of patients at the onset of type 1 diabetes and to determine if these findings are age related. For this purpose, 68 newly diagnosed type 1 diabetes mellitus patients referred to our hospital between 1997 and 1999 were studied; 42 were adults (mean age 24+/-3.5 years) and 26 children (mean age 6.1+/-4 years). Autoantibody markers islet cell antibodies, glutamic acid decarboxylase antibodies (GADA) and tyrosine phosphatase antibodies (IA-2A), pancreatic reserve (glucagon test) and HbA1c were determined. Some clinical characteristics, such as mode of presentation and insulin requirements, were also analysed. Type 1 diabetes mellitus was found to be autoimmune in 83.8% of the patients and idiopathic in 16.2%, without significant differences between adults and children. In the whole autoimmune group, GADA was more prevalent in adults and IA-2A more frequent in children. On the other hand, adults showing autoimmune markers developed ketosis more frequently and needed higher insulin doses at diagnosis, while children did not exhibit clinically significant differences associated with the presence or absence of antibodies. In conclusion, in children the presence of autoimmune markers is not related to the mode of presentation or characteristics of type 1 diabetes. In adults, however, the autoimmune group presents with more-severe clinical disease than antibody negative patients. Age at onset seems to be an important parameter in the natural history of type 1 diabetes and must be taken into account in epidemiological or intervention studies. Topics: Adult; Aging; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucagon; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Pancreas; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases | 2001 |
Human islet transplantation network for the treatment of Type I diabetes: first data from the Swiss-French GRAGIL consortium (1999-2000). Groupe de Recherche Rhin Rhĵne Alpes Genève pour la transplantation d'Ilots de Langerhans.
Improvements in islet transplantation require clinical series large enough to implement controlled new strategies. The goal of this study was to demonstrate the feasibility of a multicentre network for islet transplantation in Type I (insulin-dependent) diabetic patients.. The five centres (Besançon, Geneva, Grenoble, Lyon, Strasbourg) of the GRAGIL network allow pancreas procurement, recipient recruitment, transplantation procedure and follow-up. Islet isolation is, however, performed in one single laboratory (Geneva). Pancreata were procured in each of the five centres and transported to Geneva with an ischaemia time of less than 8 hours. Islets were isolated using a standard automated method. If the islet number was too low for a graft (< 6,000 Islet-equivalent/kg), islets were cultured up to 12 days until another isolation was possible. Islets were transplanted by percutaneous transhepatic intraportal injection. Immunosuppression consisted of cyclosporine, mycophenolate mofetil, steroids and an anti-interleukin 2 receptor antibody.. From March 1999 to June 2000, 56 pancreata procurements were performed with an average yield of 234500 islet-equivalent, with 32 preparations over 200000 islet-equivalent. Ten C-peptide negative Type I diabetic patients (5 men and 5 women, median age 44 years, median diabetes duration 29 years) with an established kidney graft (> 6 months) received 9,030 +/- 1,090 islet-equivalent/kg with a median purity of 63 %. The number of pancreata required for each graft was 1 (n = 5) or 2 (n = 5). At the completion of a 12 month follow-up, we observed 0% primary nonfunction, 50% graft survival and 20% insulin-independence.. This study demonstrates the interest and the feasibility of a multicentre collaboration in human islet transplantation. Topics: Adult; Age of Onset; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; Patient Selection; Tissue and Organ Procurement; Treatment Outcome | 2001 |
C-peptide prevents and improves chronic Type I diabetic polyneuropathy in the BB/Wor rat.
Insulin and C-peptide exert neuroprotective effects and are deficient in Type I (insulin-dependent) diabetes mellitus but not in Type II (non-insulin-dependent) diabetes mellitus. These studies were designed to test the preventive and interventional effects of C-peptide replacement on diabetic polyneuropathy in the Type I diabetic BB/Wor rat.. Diabetic BB/Wor rats were replaced with rat C-peptide from onset of diabetes and between 5 and 8 months of diabetes. They were examined at 2 and 8 months and compared to non-C-peptide replaced BB/Wor rats, Type II diabetic (non-C-peptide deficient) BB/Z rats and non-diabetic control rats. Animals were monitored as to hyperglycaemia and nerve conduction velocity (NCV). Acute changes such as neural Na+/K+-ATPase and paranodal swelling were examined at 2 months, morphometric and teased fiber analyses were done at 8 months.. C-peptide replacement for 2 months in Type I diabetic rats prevented the acute NCV defect by 59% (p < 0.005), the neural Na+/K+-ATPase defect by 55% (p < 0.001) and acute paranodal swelling by 61% (p < 0.001). Eight months of C-peptide replacement prevented the chronic nerve conduction defect by 71% (p < 0.001) and totally prevented axoglial dysjunction (p < 0.001) and paranodal demyelination (p < 0.001). C-peptide treatment from 5 to 8 months showed a 13% (p < 0.05) improvement in NCV, a 33% (p < 0.05) improvement in axoglial dysjunction, normalization (p < 0.001) of paranodal demyelination, repair of axonal degeneration (p < 0.01), and a fourfold (p < 0.001) increase in nerve fibre regeneration.. C-peptide replacement of Type I BB/Wor-rats partially prevents acute and chronic metabolic, functional and structural changes that separate Type I diabetic polyneuropathy from its Type II counterpart suggesting that C-peptide deficiency plays a pathogenetic role in Type I diabetic polyneuropathy. Topics: Animals; Axons; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Disease Models, Animal; Male; Myelin Sheath; Nerve Regeneration; Neural Conduction; Rats; Rats, Inbred BB; Time Factors | 2001 |
GAD65 antibody prevalence and association with thyroid antibodies, HLA-DR in Chinese children with type 1 diabetes mellitus.
Persistent humoral autoimmunity to the enzyme glutamic acid decarboxylase (GAD) has been described in a substantial proportion of patients with type 1 diabetes mellitus. Higher prevalence of GAD antibody in diabetes patients using a new radioligand-binding assay with recombinant human GAD65 antibodies (GAD65Ab) has been seen in several studies. Using this method, we have reassessed the prevalence of GAD65Ab and investigated the association of GAD65Ab with HbA1C values, C-peptide values, HLA-DR typing and thyroid autoimmune antibody in 70 Chinese children with type 1 diabetes mellitus (mean age of onset 8.21+/-3.84 years, mean duration 3.39+/-2.54 years). Our result revealed that GAD65 antibodies were present in 54.3% (38/70) of diabetes children. There was no significant difference in gender, diabetes onset and duration, HbA1c, C-peptide concentration and frequencies of HLA DR3, DR4, DR9, DR3/DR4, DR3/DR9 and DR4/DR9 genotypes between GAD65Ab+ and GAD65Ab- groups. There was no negative correlation between GAD65Ab values and duration of diabetes in those with GAD65Ab positivity (r=-0.239, P>0.05). The frequencies of antimicrosomal and anti-thyroglobulin antibodies in GAD65Ab+ (13.5,8.1%, respectively) were not different from GAD65- patients (9.4,12.5%, respectively). Topics: Adolescent; Age of Onset; Asian People; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; HLA-DR Antigens; Humans; Immunoglobulins, Thyroid-Stimulating; Infant; Isoenzymes; Male; Radioligand Assay; Recombinant Proteins; Taiwan | 2001 |
Cows' milk proteins cause similar Th1- and Th2-like immune response in diabetic and healthy children.
Cows' milk proteins have been proposed to play a part in the pathogenesis of Type I (insulin-dependent) diabetes mellitus but both epidemiological and immunological studies have given conflicting results. Thus we aimed to study the immunological response to cows' milk proteins among diabetic and healthy children, focusing on the balance of Th1- and Th2-like lymphocytes.. Peripheral blood mononuclear cells from 30 Type I diabetic children (4 to 18 years old) were examined and compared with peripheral blood mononuclear cells from 18 healthy age-matched control children (7 to 15 years old). Expression of IFN-gamma and IL-4 mRNA were detected by realtime RT-PCR and as protein by ELISA after stimulation with BSA, the ABBOS-peptide (a. a. 152-169) and beta-lactoglobulin (betaLG) from cows' milk and ovalbumin from hens' egg. Phytohaemagglutinin and keyhole limpet haemocyanin were used as positive and negative controls, respectively.. Bovine serum albumin caused a weak Th2-like response in Type I diabetic children, whereas BSA antibodies decreased with age only among healthy children. Otherwise, cows' milk proteins (BSA, ABBOS and betaLG) caused increased expression for IFN-gamma and IL-4 mRNA in diabetic and healthy children. BetaLG caused the strongest immunological response, which decreased with age only among diabetic children. However, ovalbumin from egg caused a similar activation of the immune system and the immune response was similar in both diabetic and healthy children.. Proteins from cows' milk caused an equal Th1- and Th2-like immune response in diabetic and healthy children. Thus, our results do not support the hypothesis that cows' milk antigens are important for the immune process associated with Type I diabetes. Topics: Adolescent; Animals; Antibodies; Antigens; C-Peptide; Cattle; Child; Child, Preschool; Diabetes Mellitus, Type 1; Dietary Proteins; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Hemocyanins; Humans; Insulin; Interferon-gamma; Interleukin-4; Lactoglobulins; Male; Milk Proteins; Ovalbumin; Peptide Fragments; Phytohemagglutinins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Serum Albumin, Bovine; Th1 Cells; Th2 Cells | 2001 |
Failure to develop diabetic ketoacidosis in a newly presenting type 1 diabetic patient.
Topics: Addison Disease; Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glucagon; Humans; Triglycerides | 2001 |
Insulin independence and normalization of oral glucose tolerance test after islet cell allotransplantation.
To achieve permanent normoglycemia in patients with type I diabetes, it is necessary to renew the insulin-producing beta-cells by transplantation of either a vascularized pancreatic graft or isolated islets of Langerhans. Presently, about 10% of patients with type I diabetes undergoing islet allotransplantation achieve insulin independence; however, glucose intolerance remains in the majority of cases. We report a case of long-term insulin independence after islet allotransplantation in a type I diabetic patient. Three years after islet transplantation, the patient remains insulin-independent with a normal oral glucose tolerance test (OGTT). The patient therefore no longer meets the World Health Organization criteria for the diagnosis of diabetes mellitus and demonstrates that islet transplantation can cure diabetes in type I diabetic patients. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Reference Values; Time Factors; Transplantation, Homologous | 2001 |
Is the process of beta-cell destruction in type 1 diabetes at time of diagnosis more extensive in females than in males?
To evaluate sex differences in patients with insulin-dependent diabetes mellitus (type 1 diabetes) by comparing the integrated parameters of metabolic control at the time of clinical diagnosis and 3 months after intensive insulin therapy in pre-pubertal, pubertal and post-pubertal patients.. A total of 331 consecutive patients with newly diagnosed type 1 diabetes were studied. The mean age of the group was 15 years (s.d. 8.1; range 5-23 years). Patients were stratified into three groups according to their age at disease onset: pre-pubertal (ages 5-9 years), pubertal (ages 10-18 years) and post-pubertal (ages 19-23 years).. Glycated haemoglobin (HbA(1c)), insulin dose and both basal and glucagon-stimulated C-peptide were evaluated at diagnosis and after 3 months of insulin therapy.. We found that females diagnosed after puberty were those with the lowest basal C-peptide compared with males (P=0.005). No statistically significant differences were observed for other metabolic parameters. When the entire group was evaluated, females at the time of diagnosis showed significant lower body mass index (P=0.001), lower basal C-peptide (P=0.021) and higher HbA(1c) (P=0.023) and required more insulin than males (P<0.001). After 3 months of therapy, only a significantly greater dose of insulin was observed in females compared with males (P=0.001), with similar good metabolic control as assessed by HbA(1c).. We conclude that the process of beta-cell destruction at diagnosis may be more extensive in post-pubertal females than in males. Moreover, after the introduction of insulin therapy, females and males show similar metabolic parameters, although females still require significantly more insulin than males to achieve good metabolic control, 3 months after diagnosis. Topics: Adolescent; Adult; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Puberty; Sex Characteristics | 2001 |
Immunologic issues in type 1 diabetes.
Topics: Animals; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Mice; Mice, Inbred NOD; Tumor Necrosis Factor-alpha | 2001 |
Effect of near physiologic insulin therapy on hypoglycemia counterregulation in type-1 diabetes.
The aim of this study was to examine hormonal counterregulation during insulin-induced hypoglycemia in type-1 diabetic patients during long-term near normoglycemic insulin therapy and intensive clinical care.. Type-1 diabetic patients (age 35.3 +/- 2 years, body mass index 22.8 +/- 1 kg x m(-2), mean diabetes duration 13.6 (11-17 years), mean HbA1c during the last year 6.6 +/- 0.1%) and nondiabetic subjects were studied during (0-120 min) and after (120-240 min) hypoglycemic (3.05 mmol/l) hyperinsulinemic (approximately 330 pmol/l) clamp tests.. During hypoglycemia peak plasma concentrations of glucagon (199 +/- 16 vs. 155 +/- 11 ng/l, p < 0.05), epinephrine (4,514 +/- 644 vs. 1,676 +/- 513 pmol/l, p < 0.001), norepinephrine (2.21 +/- 0.14 vs. 1.35 +/- 0.19 nmol/l, p < 0.01) and cortisol (532 +/- 44 vs. 334 +/- 61 nmol/l) were reduced in the diabetic patients. Plasma lactate did not change from baseline values (0.51 +/- 0.06 mmol/l) in diabetic but doubled in healthy subjects (1.13 +/- 0.111 mmol/l, p < 0.001 vs. control). During the posthypoglycemic recovery period plasma concentrations of free fatty acids were higher in diabetic patients at 240 min (1.34 +/- 0.12 vs. 2.01 +/- 0.23 mmol/l, p < 0.05).. Despite long-term near physiologic insulin substitution and the low incidence of hypoglycemia, hormonal hypoglycemia counterregulation was impaired in type-1 diabetic patients after a diabetes duration of more than 10 years. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Glucose; Hormones; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Lactic Acid; Male; Middle Aged; Reference Values | 2001 |
Automated chemiluminescent assay for C-peptide.
C-peptide is secreted in equimolar concentrations with insulin, and is often measured to assess pancreatic beta-cell function. C-peptide analysis is most often performed by radioimmunoassay (RIA) which has several disadvantages. We evaluated an automated, chemiluminescent immunoassay for C-peptide in terms of precision, linearity, interference, and correlation with a RIA method. The chemiluminescent assay demonstrated acceptable correlation with the RIA method (slope = 0.82, y-intercept = 0.88 ng/ml, r-value = 0.97). Between-run Cvs ranged from 8 to 9%, which compared well with the RIA method. Linearity extended beyond the manufacturer's recommendations and recovery ranged from 87 to 112% across the concentrations tested, with a slope of 1.007. No significant interference was noted with hemoglobin, bilirubin, or triglyceride. Overall this method compared favorably with the RIA method and offers an alternative to RIA for the analysis of C-peptide. Topics: Bilirubin; C-Peptide; Calibration; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Hemoglobins; Humans; Immunoassay; Indicator Dilution Techniques; Luminescent Measurements; Radioimmunoassay; Reagent Kits, Diagnostic; Reproducibility of Results; Sensitivity and Specificity; Triglycerides | 2000 |
Serological markers of recurrent beta cell destruction in diabetic patients undergoing pancreatic transplantation.
Besides alloimmunity to transplanted pancreatic tissue, recurrent autoimmune beta cell destruction is an additional limitation to successful clinical pancreatic allografts in type 1 diabetic patients.. We studied the prevalence of autoantibodies to glutamate decarboxylase (GAD) 65 and tyrosine phosphatase (IA-2) in 68 C-peptide-negative diabetic patients receiving pancreatic allografts. Sera from patients were obtained immediately before grafting. A second blood sample was analyzed at the time of graft failure in patients who returned to hyperglycemia and during the same follow-up period in those who experienced a functional pancreatic allograft. Patients were classified according to clinical outcome into chronic graft failure (group A, n=20), acute graft failure and/or arterial thrombosis (n=7), or functional pancreatic graft (group C, n=41). Sera from patients were screened for the presence of specific autoantibodies using an islet cell autoantibody assay, a combi-GAD and IA-2 test, and individual GAD and IA-2 assays.. Patients from group A had significantly higher combi-test values than patients from group C (13+/-16 vs. 4.5+/-12 units, P<0.02) and higher anti-GAD65 antibody (Ab) levels (0.19+/-0.3 vs. 0.04+/-0.13 units, P<0.01) immediately before grafting. After graft failure in group A, both anti-GAD65 and anti-IA-2 Ab levels increased from baseline, but only the increase in anti-IA-2 Ab levels reached statistical significance (0.28+/-0.12 vs. 15+/-34, P=0.03). When compared with group C, patients from group A had higher anti-GAD65 Abs (0.29+/-0.35 vs. 0.05+/-0.16, P<0.001) after graft failure. Interestingly, the number of double-Ab-positive patients rose from 5% to 35% in group A, whereas it remained at 5% in group C. In pancreatic transplants with bladder drainage, the presence of anti-GAD65 and/or anti-IA2 Abs was not associated with a reduction in urinary amylase levels. This suggests that a loss of endocrine function was not associated with exocrine failure in patients from group A.. We can conclude from the present study that peripheral autoimmune markers are useful in diabetic patients receiving pancreatic allografts. Topics: Adult; Amylases; Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Islets of Langerhans; Isoenzymes; Male; Middle Aged; Pancreas; Pancreas Transplantation; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Recurrence; Treatment Failure; Treatment Outcome | 2000 |
Residual beta-cell function and microvascular complications in type 1 diabetic patients.
To determine the influence of residual beta-cell function on retinopathy and microalbuminuria we measured basal C-peptide in 50 type 1 diabetic outpatients aged 24.96 +/- 7.14 years, with a duration of diabetes of 9.1 +/- 6.2 years. Forty-three patients (86%) with low C-peptide (<0.74 ng/ml) had longer duration of diabetes than 7 patients (14%) with high C-peptide (> or =0.74 ng/ml) (9 (2-34) vs 3 (1-10) years, P = 0.01) and a tendency to high glycated hemoglobin (HBA1) (8.8 (6-17.9) vs 7.7 (6.9-8.7)%, P = 0. 08). Nine patients (18%) had microalbuminuria (two out of three overnight urine samples with an albumin excretion rate (AER) > or =20 and <200 microg/min) and 13 (26%) had background retinopathy. No association was found between low C-peptide, microalbuminuria and retinopathy and no difference in basal C-peptide was observed between microalbuminuric and normoalbuminuric patients (0.4 +/- 0.5 vs 0.19 +/- 0.22 ng/ml, P = 0.61) and between patients with or without retinopathy (0.4 +/- 0.6 vs 0.2 +/- 0.3 ng/ml, P = 0.43). Multiple regression analysis showed that duration of diabetes (r = 0. 30, r2 = 0.09, P = 0.031) followed by HBA1 (r = 0.41, r2 = 0.17, P = 0.01) influenced basal C-peptide, and this duration of diabetes was the only variable affecting AER (r = 0.40, r2 = 0.16, P = 0.004). In our sample of type 1 diabetic patients residual ss-cell function was not associated with microalbuminuria or retinopathy. Topics: Adult; Albumins; Albuminuria; Analysis of Variance; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Humans; Islets of Langerhans; Male | 2000 |
Both insulin sensitivity and insulin clearance in children and young adults with type I (insulin-dependent) diabetes vary with growth hormone concentrations and with age.
We measured insulin clearance rates in children and young adults with Type I (insulin-dependent) diabetes mellitus to establish their relation with insulin sensitivity and with factors such as growth hormone secretion and body mass index.. We studied 46 subjects mean (range) age 14.4 (9.8-24.6) years), body mass index 21.1 (15.8-29.6) Kgm2[ using an overnight (1800-0800 hours) variable rate insulin infusion euglycaemic clamp protocol (5 mmol/l). Plasma free insulin concentrations during steady-state euglycaemia were used as an index of insulin sensitivity and insulin clearance determined as a ratio of insulin infusion rate to plasma free insulin.. During steady-state euglycaemia (0500-0730 hours), insulin sensitivity mean (SEM) plasma insulin 0.020 (0.002) mU/l[ and insulin clearance rates 19.1 (1.8) ml.kg-1.min[ varied with age non-linearly and in a reciprocal fashion to each other (cubic regression F = 4.09, p = 0.01; F = 3.55, p = 0.02, respectively). Insulin sensitivity was negatively related to BMI (r = -0.37, p = 0.011) and mean overnight growth hormone concentrations (r = -0.40, p = 0.007). Insulin clearance was only related to growth hormone concentrations (r = -0.37, p = 0.014). These relations were still evident after stepwise multiple regression analysis (potential determinants: C peptide, sex, age, puberty stage, HbA1c, duration of diabetes): insulin sensitivity r = 0.55, p < 0.001; insulin clearance r = 0.37, p < 0.02.. Insulin clearance rates vary with age in young subjects with Type I diabetes and are highest during mid-adolescence when insulin sensitivity is at its lowest. Both insulin sensitivity and insulin clearance are related to circulating growth hormone concentrations. Topics: Adolescent; Adult; Age Factors; Blood Glucose; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Human Growth Hormone; Humans; Hypoglycemic Agents; Insulin; Male; Metabolic Clearance Rate; Regression Analysis; Sex Factors | 2000 |
Impaired insulin secretion in non-diabetic offspring of probands with latent autoimmune diabetes mellitus in adults.
This study was undertaken to investigate metabolic and genetic characteristics of latent autoimmune diabetes in adults (LADA).. We evaluated insulin secretory capacity with oral and intravenous glucose tolerance tests (early insulin response) and hyperglycaemic clamp (insulin secretory capacity) and the rates of whole body glucose uptake with the euglycaemic clamp, HLA-DQB1 genotypes (time-resolved fluorescence) and islet cell antibodies (ICA) (immunofluorescence) and antibodies to glutamic acid decarboxylase (GAD) (radio-immunoprecipitation) in 36 non-diabetic offspring (LADA-offspring) of patients with Type II (non-insulin-dependent) diabetes mellitus who tested positive for ICA and/or GAD antibodies during the 10-year follow-up from the diagnosis and in 19 healthy control subjects without a family history of diabetes.. The early insulin response during the first 10 min of an intravenous glucose tolerance test was about 40% lower in the LADA-offspring than in the control group (p = 0.008). Insulin secretory capacity in the hyperglycaemic clamp was also about 30% lower in the LADA-offspring (p = 0.048). The rates of whole body glucose uptake were similar in both groups. The frequency of low risk HLA-DQB1 genotypes was higher in the LADA-offspring than among Finnish healthy blood donors (p = 0.033). The risk conferring genotypes were associated with the lowest tertile of insulin secretory capacity in the LADA-offspring (p = 0.032). There were no associations between the autoantibodies and early insulin response or insulin secretory capacity within the study groups.. We conclude that LADA is a familial disease involving most likely gene defects leading to a slow progressive beta-cell destruction and insulin deficiency. Topics: Adipose Tissue; Adult; Autoantibodies; Blood Glucose; Body Constitution; C-Peptide; Calorimetry, Indirect; Case-Control Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Energy Metabolism; Fatty Acids, Nonesterified; Female; Glucose Clamp Technique; Glucose Tolerance Test; Glutamate Decarboxylase; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Longitudinal Studies; Male; Nuclear Family | 2000 |
The ABBOS-peptide from bovine serum albumin causes an IFN-gamma and IL-4 mRNA response in lymphocytes from children with recent onset of type 1 diabetes.
The ABBOS-peptide from bovine serum albumin (BSA) in cow's milk has been suggested to initiate the autoimmune process against the beta-cells leading to type 1 diabetes. The aim of this study was to elucidate if the ABBOS-peptide is a possible trigger of type I diabetes. The cytokines IL-4 and IFN-gamma were determined at the level of transcription as mRNA in lymphocytes, stimulated with the ABBOS-peptide. Sixteen children with newly diagnosed type 1 diabetes were compared with 10 healthy controls matched for the diabetes associated HLA-type DR3/4. Antibodies to bovine serum albumin (BSA), insulin antibodies (IA), and antibodies against islet cells (ICA) were determined, as well as serum C-peptide. Increased mRNA expression for IFN-gamma and/or IL-4 could be observed in lymphocytes from 13/16 children with recent onset of diabetes after in vitro stimulation with the ABBOS-peptide. Low expression of IFN-gamma mRNA was associated with high secretion of C-peptide, whereas a positive relationship could be observed between expression of IL-4 mRNA and insulin antibodies. Expression of IFN-gamma and/or IL-4 mRNA was also detected in lymphocytes from 6/10 healthy controls. ABBOS may have a role as a reactive epitope in the upregulation of the autoimmune process against the beta-cells but ABBOS does not seem to cause any specific Th1 response. An increased mRNA expression could also be seen in lymphocytes from healthy controls. Thus, the ABBOS-peptide might just cause or reflect an unspecific immune activity. Topics: Adolescent; Adult; Animals; Autoantibodies; C-Peptide; Cattle; Cells, Cultured; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Insulin Antibodies; Interferon-gamma; Interleukin-4; Lymphocytes; Middle Aged; Milk; Peptide Fragments; Reference Values; RNA, Messenger; Serum Albumin, Bovine; Transcription, Genetic | 2000 |
Human islet transplantation: lessons from 13 autologous and 13 allogeneic transplantations.
A series of 13 islet autotransplantations and 13 islet allotransplantations performed between 1992 and 1999 at the University Hospital of Geneva are presented. Factors affecting the outcome are analyzed.. Islet autotransplantation has been performed in seven patients with chronic pancreatitis and in six patients with benign tumors undergoing extensive pancreatectomy. Islet allografts were performed in C-peptide-negative patients simultaneously or after a kidney or lung transplantation. Each recipient received islets from one to four donors. Panel-reactive antibodies were monitored by microlymphocytotoxicity test.. Eleven of 13 patients who underwent autotransplantation maintained insulin independence for 6 months to 5 years. Two years after autologous islet transplantation, five of nine patients were insulin independent with an glycosylated hemoglobin of 5.9%. Three late islet failures occurred in patients with chronic pancreatitis. Islet yield was significantly lower in patients with chronic pancreatitis than in patients with benign tumors (2044 equivalent islet number/gram resected pancreas versus 5184 equivalent islet number/gram; P=0.037). In islet allotransplantation, no early graft loss was found. All 13 patients who underwent allotransplantation had basal C-peptide levels above 0.3 nmol/L for 3 months to 5 years. Mean glycosylated hemoglobin decreased from 9.1% before transplantation to 5.5% at month 3. Insulin independence was achieved in two type I diabetic patients. In four of six patients with graft failure, the graft had induced panel-reactive antibodies.. In islet autotransplantation, the reduced number of islets that can be isolated from fibrotic pancreata may be the major limiting factor. In islet allotransplantation, early graft function can now be consistently achieved. Islet allografts seem to be highly immunogenic, and chronic islet failure cannot be prevented consistently by conventional immunosuppression. Topics: Autoimmunity; Biopsy; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Graft Rejection; Graft Survival; Humans; Islets of Langerhans Transplantation; Liver; Pancreatectomy; Transplantation, Autologous; Transplantation, Homologous | 2000 |
The increase in sympathetic nerve activity after glucose ingestion is reduced in type I diabetes.
Food intake is followed by an increase in baroreflex-governed sympathetic outflow to muscle vessels. It is established that insulin contributes to this stimulation; however, the increase occurs (to a lesser degree) even in the absence of enhanced insulin secretion. To further elucidate the role of insulin, muscle nerve sympathetic activity was recorded by microneurography, and the increase after an oral 100-g glucose load in eight C-peptide-negative patients with type I diabetes without any signs of neuropathy was compared with that in 16 healthy control subjects. The level of sympathetic activity at rest was similar in the two groups (type I diabetes patients, 19.5+/-2.4 bursts/min; controls, 20.4+/-4.8 bursts/min; means+/-S.D.). Following glucose intake there was a significant increase in activity in both groups, with maximum values at 30 min of 24.3+/-3.7 bursts/min for type I diabetes patients and 34.4+/-9.1 bursts/min for controls. The summarized response (during 90 min) of the diabetic patients was less than half that of the control subjects (P=0.0003). It is concluded that the response of muscle nerve sympathetic activity to glucose ingestion is reduced to about half of its normal strength in the absence of insulin, and that there is no difference in sympathetic outflow at rest between healthy subjects and diabetic patients without polyneuropathy. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Heart Rate; Humans; Insulin; Male; Muscle, Skeletal; Sympathetic Nervous System | 2000 |
Human anti-murine antibodies interfere with CPR assays performed with commercial kits.
Quantitation of C-peptide is important for the assessment of insulin secretion, in particular in patients receiving insulin therapy. Since the CPR levels become much higher than the concentration of C-peptide for several reasons, such as the high concentration of proinsulin, CPR values sometimes need to be assessed carefully. We have had two diabetic patients whose CPR values were abnormally high when determined with a Daiichi C-peptide kit III (method 1). CPR values determined by other methods were from two to ten times lower, indicating considerable interference when method 1 was used. Since method 1 uses mouse monoclonal antibodies (mmab) for detection antibodies, we suspected that human anti-murine antibodies (HAMA) were responsible for the interference. HAMA were detected in serum from both patients (45 and 460 ng/ml in case 1 and case 2 (at peak), respectively). Removal of HAMA from serum eliminated the interference. Modification of method 1 to exclude mmab from the assay system removed all interference. HAMA were, therefore, considered to be the cause of the interference. In case 2, the peak concentration of HAMA was recorded 16 months earlier than the maximum of interference. Further analysis revealed that HAMA with high affinities were responsible for the interference. Topics: Aged; Animals; Antibodies; Antibodies, Monoclonal; Artifacts; C-Peptide; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glyburide; Humans; Hypoglycemic Agents; Insulin; Mice; Proinsulin; Radioimmunoassay; Reagent Kits, Diagnostic; Reagent Strips; Reproducibility of Results | 2000 |
Diurnal blood pressure variations in incipient and end stage diabetic renal disease.
Our aim was to compare the diurnal blood pressure patterns of people with Type 1 diabetes on continuous ambulatory peritoneal dialysis (CAPD, n=9) or haemodialysis (n=10) to diabetic patients with normo-albuminuria (n=12) or micro-albuminuria (n=15). Blood pressure was measured with an ABPM02 Meditech oscillometric blood pressure monitor. The micro-albuminuric group had significantly higher nocturnal diastolic and mean arterial pressures than the normo-albuminuric group. CAPD and haemodialysis patients had significantly higher day time, nocturnal mean systolic, diastolic and mean arterial blood pressures. Micro-albuminuric and end-stage renal failure patients displayed a loss of the physiological drop of systolic blood pressure, which was only significant in the normo-albuminuric group. Nocturnal drop of blood pressure characterised by diurnal indices were 7.4% in the CAPD, 8.8% in the haemodialysis, 10.0% in the micro-albuminuric and 16.5% in the normo-albuminuric group. These results suggest, that pathological circadian blood pressure variation is common in diabetic patients on dialysis, and ambulatory blood pressure monitoring can be a useful tool both in its the detection and its adequate treatment. Topics: Adult; Albuminuria; beta 2-Microglobulin; Blood Glucose; Blood Pressure; Blood Pressure Monitoring, Ambulatory; Blood Urea Nitrogen; C-Peptide; Cholesterol; Circadian Rhythm; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glycated Hemoglobin; Humans; Hypertension; Kidney Failure, Chronic; Male; Middle Aged; Peritoneal Dialysis, Continuous Ambulatory; Renal Dialysis; Triglycerides | 2000 |
Ketoacidosis in young adults is not related to the islet antibodies at the diagnosis of Type 1 diabetes mellitus--a nationwide study.
To test the hypothesis that there is lower prevalence of islet antibodies in subjects with newly diagnosed Type 1 diabetes mellitus in young adulthood than in children is associated with less severe diabetes at time of diagnosis.. This investigation was based on a nationwide study (Diabetes Incidence Study in Sweden) of 15-34-year-old newly diagnosed diabetic subjects. During 1992-1993, all diabetic subjects (excluding secondary and gestational diabetes) were reported on standardized forms, with information about clinical characteristics at diagnosis. The study examined islet cell antibodies (ICA) by indirect immunofluorescence, and autoantibodies to glutamic acid decarboxylase (GADA), tyrosine phosphatase-like antigen (IA-2A) and insulin (IAA) as well as C-peptide by radioimmunoassay.. Blood samples were available from 78 patients with diabetic ketoacidosis (DKA) and 517 non-acidotic patients. The prevalence of ICA (63% vs. 57%), GADA (63% vs. 66%), IA-2A (35% vs. 44%) and IAA (20% vs. 15%) were very similar in patients with or without DKA. The median levels of the four autoantibodies did not differ between the two groups. High blood glucose (P < 0.001) and low C-peptide levels (P < 0.001) were the only parameters found to be related to DKA.. The similarities in findings of newly diagnosed diabetic patients with or without DKA regarding ICA, GADA, IA-2A and IAA suggest that there is no relationship between the expression of antigenicity and the severity of beta-cell dysfunction. The lower prevalence of the four autoantibodies in 15-34-year-old diabetic subjects compared with previous findings in children is not explained by misclassification of diabetes type. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Fluorescent Antibody Technique, Indirect; Glutamate Decarboxylase; Humans; Incidence; Insulin Antibodies; Islets of Langerhans; Male; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases; Receptor-Like Protein Tyrosine Phosphatases, Class 4; Receptors, Cell Surface; Sweden | 2000 |
Role of islet autoimmunity in the aetiology of different clinical subtypes of diabetes mellitus in young north Indians.
To determine the role of islet autoimmunity in the aetiology of different clinical subtypes of diabetes mellitus in young north Indian patients by measuring islet autoantibodies.. In a cross-sectional study, 145 young patients with diabetes (onset < 30 years) were subdivided into the following categories: Type 1 diabetes (n = 83), malnutrition-modulated diabetes mellitus (MMDM, n = 31) and fibro-calculous pancreatic diabetes (FCPD, n = 31). MMDM subjects presented with emaciation and severe insulin-requiring but ketosis-resistant diabetes, while FCPD was associated with idiopathic chronic calcific pancreatitis. Antibodies to glutamic acid decarboxylase (GADA) and IA-2 (IA-2 A) were detected by immunoprecipitation of 35S-labelled recombinant antigens and cytoplasmic islet cell antibody (ICA) by indirect immunofluorescence.. GADA were present in a significant proportion (23%) of patients with MMDM. In contrast, IA-2 A was increased only among patients with Type 1 diabetes (22%), but not MMDM (3%, P < 0.05). Among patients with a duration of diabetes < 2 years, GADA and/or IA-2 A were found in 61% of Type 1 diabetic and 37% of MMDM patients (P < 0.01). MMDM patients who were positive for GADA had a shorter duration of diabetes, but did not differ in their age at onset of diabetes, body mass index, fasting plasma C-peptide, or frequency of thyroid microsomal and parietal cell antibodies. FCPD subjects had the lowest prevalence of autoantibodies: IA-2 and ICA were absent, while GADA were present in 7% (P < 0.05 vs. Type 1 diabetes).. GADA, though not IA-2 A, were present in a substantial proportion of patients with the MMDM variant of diabetes, suggesting that islet autoimmunity may play a role in its pathogenesis. In contrast, none of the islet antibodies was increased in subjects with FCPD, making it likely that it is a secondary type of diabetes. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; C-Peptide; Calcinosis; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Fluorescent Antibody Technique, Indirect; Glutamate Decarboxylase; Humans; India; Islets of Langerhans; Male; Nutrition Disorders; Pancreatitis | 2000 |
Young Chinese adults with new onset of diabetic ketoacidosis--clinical course, autoimmune status and progression of pancreatic beta-cell function.
To examine the clinical course, autoimmune status and pancreatic beta cell function, over a 2-year period, in young Chinese subjects newly presenting with diabetic ketoacidosis (DKA).. A prospective study involving 562 out of 27,893 patients who were admitted to the medical ward with a principal diagnosis of diabetes mellitus during the recruitment period of 1 year.. Of these 562 patients, 27 were aged less than 35 years and admitted with a diagnosis of DKA and 11 (six males and five females) of these were newly diagnosed. Antibodies to glutamic acid decarboxylase (GAD) were present in five patients. Anti-ICA 512 was not detected in any of the patients. Basal and post-glucagon stimulated plasma C-peptide remained in the insulin-deficient range although showing improvement at 2 years.. These findings confirm the relative rarity of autoimmune Type 1 diabetes in young Chinese. Even when the clinical presentation takes the extreme form of acute DKA, less than 50% have positive autoimmune markers. Topics: Adult; Asian People; Autoantibodies; Blood Glucose; C-Peptide; China; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Follow-Up Studies; Glucagon; Glutamate Decarboxylase; Hong Kong; Humans; Islets of Langerhans; Male | 2000 |
[Latent autoimmune (type 1) diabetes mellitus in patients originally classified as type 2. Divergence of etiologic markers].
To assess the prevalence of markers of autoimmune insulitis (AII) in patients classified originally as having Type-2 diabetes mellitus (Type-2 DM). 386 patients subdivided according to the BMI, C-peptide and type of treatment.. Age, BMI, C-peptide, Glutamic acid decarboxylase autoantibodies (GADA), HLA-DR/,-DQ alleles. Prevalence of GADA varied from < 5% in obese patients with normal/increased C-peptide to > 30% in non-obese patients with low C-peptide. In majority of GADA positive patients, the Type-1 DM high-risk HLA-DRB1*, HLA-DQB1* alleles have been found. Among them HLA-DRB1*0302 and HLA-DRB1*0201 were more frequent than HLA-DRB1*040x and HL:A-DQB1*0302.. Significant fraction of patients classified initially as Type-2 DM may have in fact Type-1 DM. Such patients can be recognized on the basis of assessment of serological (GADA) and immuno-genetical (HLA-DR/,-DQ alleles) markers. In some patients clinical, metabolic, immune, and immunogenetic markers may disagree. This divergence stresses multifactorial genesis of diabetes. Moreover, it can also suggest that both autoimmune insulitis and insulin resistance may coexist in parallel. Topics: Adult; Aged; Aged, 80 and over; Autoantibodies; Autoimmune Diseases; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; HLA-DQ Antigens; HLA-DR Antigens; Humans; Male; Middle Aged | 2000 |
High frequency of persisting or increasing islet-specific autoantibody levels after diagnosis of type 1 diabetes presenting before 40 years of age. The Belgian Diabetes Registry.
To study the presence and levels of GAD65 antibodies (GADA), IA-2 antibodies (IA-2-A), and islet cell antibodies (ICA) during the first years after clinical onset of type 1 diabetes in relation to age at diagnosis.. Type 1 diabetic patients (n = 194) <40 years of age were consecutively recruited at the time of diagnosis by the Belgian Diabetes Registry and followed during the first 4 years of insulin treatment. ICA were determined by indirect immunofluorescence assay and IA-2-A, GADA, and insulin autoantibodies by a radioligand assay.. Overall, 94% of initially antibody-positive patients (n = 180) remained positive for at least 1 antibody type 4 years after diagnosis. In the case of diagnosis after 7 years of age, GADA, IA-2-A, and ICA persisted in 91, 88, and 71%, respectively, of the initially antibody-positive patients. Antibody persistence was lower in those diagnosed at <7 years of age, amounting to 60% for GADA, 71% for IA-2-A, and 39% for ICA. In 57% of the initially antibody-positive patients, at least 1 type of autoantibody reached peak values after diagnosis. This occurred more frequently for clinical onset after 7 years of age and more often for GADA (49%) than for IA-2-A (29%) or ICA (19%). Of the patients, 24% that were negative for GADA at onset became GADA-positive during the following 4 years. Among the 7% initially antibody-negative patients, 2 of 14 subjects developed antibodies after clinical onset.. In particular, for diagnosis after 7 years of age, islet cell-specific autoantibodies generally persist for many years after diagnosis. There is also a high frequency of increasing antibody levels and of conversion to antibody positivity in the first 4 years after diagnosis and start of insulin treatment. Thus, determination of antibodies at diagnosis can underestimate the number of cases with autoimmune type 1 diabetes, in particular with assays of lower sensitivity. The divergent temporal patterns of ICA, GADA, and IA-2-A suggest that the ICA test recognizes other antibody specificities besides GADA and IA-2-A and reflects other autoimmune processes; it also indicates that GADA assays have a higher diagnostic sensitivity in the period after clinical onset. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Belgium; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Infant; Male; Registries; White People | 2000 |
Characteristics of Caucasian type 2 diabetic patients during ketoacidosis and at follow-up.
To analyse among adult Caucasian patients hospitalised for diabetic ketoacidosis the relative frequency of patients with type 2 diabetes and their characteristics.. A retrospective review of adult patients presenting with diabetic ketoacidosis was conducted between 1993 and 1996. Patients with typical type 1 diabetes were classified according to age of onset < 35 years, insulin-dependence and BMI < 25 kg/m2; patients who did not meet these criteria were further classified on the basis of a basal and stimulated C-peptide and the detection of antibodies to glutamic acid decarboxylase (GADA) and to islet cells (ICA).. 43 patients presenting with an episode of diabetic ketoacidosis were divided into two groups, A and B. Group A consisted of 19 patients, 17 patients classified as patients with typical type 1 diabetes and 2 patients with diabetes post-pancreatectomy. The other patients were the subjects of our study (group B; n = 20, 4 lost to follow-up). 13 patients (65% of group B = B I) were diagnosed with type 1 diabetes (median basal C-peptide: 0.15 nmol/l) and 7 patients (35% of group B = B II) with type 2 diabetes (median basal C-peptide of 1 nmol/l). Higher body mass index (BMI), shorter duration of diabetes, smaller anion gap and worse glycaemic control were found to be significantly different between groups B I and II on admission (p < 0.05). After a median follow-up of 18 months, patients in group B II had a better metabolic control than those in B I and 5 of the 7 patients were treated without insulin.. Diabetic ketoacidosis is more common than previously thought in patients with type 2 diabetes, occurring in 16% of all cases. Distinctive features at presentation are the degree of acidosis, the duration of diabetes, BMI and HbA1c. However, the basal plasma C-peptide value remains the best discriminating factor. Topics: Adult; Age of Onset; Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Follow-Up Studies; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Male; Middle Aged; Pancreatectomy; Retrospective Studies; Switzerland; White People | 2000 |
Good "negative results".
Topics: C-Peptide; Clinical Trials as Topic; Diabetes Mellitus, Type 1; Humans; Hypoglycemic Agents; Insulin; Methotrexate; Publishing; Research Design | 2000 |
Long-term follow-up of infants of mothers with type 1 diabetes: evidence for hereditary and nonhereditary transmission of diabetes and precursors.
To estimate the impact of type 1 diabetes during pregnancy on transgenerational genetically caused and/or fuel-mediated amplification of types 1 and 2 diabetes and to estimate the impact of elevated amniotic fluid insulin levels.. A total of 75 white offspring of type 1 diabetic mothers and 49 control subjects of similar age and pubertal stage were examined at 5-15 years of age. All offspring had an oral glucose tolerance test. Glucose, insulin, and C-peptide were measured at 0, 30, 60, and 120 min after loading. Lipids and autoimmune antibodies were measured in fasting plasma.. Of the 75 offspring, 4 (5.3%) had overt diabetes, and 16 of 71 (22.5%) had autoimmune antibodies. Offspring of diabetic mothers had significantly higher BMI; symmetry indexes; cholesterol, glucose, insulin, and C-peptide levels; and insulin resistance than control subjects. With the exception of cholesterol, these values were significantly elevated in offspring who had elevated amniotic fluid insulin levels (>8 microU/ml, >48 pmol/l) during pregnancy compared with normoinsulinemic offspring and control subjects.. Offspring of type 1 diabetic mothers have an increased risk for diabetes later in life. The relative risk for type 1 and type 2 diabetes is 71.6 and 3.2, respectively. Type 2 diabetes-associated risk factors, such as high BMI; elevated glucose, insulin, and C-peptide levels; and insulin resistance, are related to the fetal metabolic experience in utero, as reflected by amniotic fluid insulin concentration. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Cholesterol; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Genomic Imprinting; Germany; Humans; Insulin; Lipids; Longitudinal Studies; Male; Mothers; Pregnancy; Pregnancy in Diabetics; White People | 2000 |
Stability of disease-associated antibody titers in pregnant women with type 1 diabetes with or without residual beta-cell function.
Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Isoenzymes; Pregnancy; Pregnancy in Diabetics | 2000 |
The effects ex vivo and in vitro of insulin and C-peptide on Na/K adenosine triphosphatase activity in red blood cell membranes of type 1 diabetic patients.
The decrease in Na/K adenosine triphosphatase (ATPase) activity observed in several tissues of type 1 diabetic patients is thought to play a role in the development of long-term complications. Infusion of insulin may restore this enzyme activity in red blood cells (RBCs), and recent arguments have been developed for a similar role of C-peptide. The aims of this study were to determine whether insulin acts directly on the RBC enzyme and to evaluate the effect of C-peptide on Na/K ATPase activity. Thirty-nine C-peptide-negative type 1 diabetic patients were studied (blood glucose, 11.2 +/- 1.49 mmol/L; hemoglobin A1c [HbA1c], 8.9% +/- 0.1%, mean +/- SEM). Blood samples were obtained in the morning, before breakfast and insulin injection. Intact and living RBCs were resuspended in their own plasma and incubated with or without insulin (50 microU/mL) or C-peptide (6 nmol/L). Ex vivo by microcalorimetry, the heat produced after 1 hour by the enzyme-induced hydrolysis of adenosine triphosphate (ATP), was measured in a thermostated microcalorimeter at 37 degrees C. The results showed that Na/K ATPase activity was significantly increased by insulin (12.4 +/- 0.5 v 15.4 +/- 0.9 mW/L RBCs, P < .05, n = 23) but not by C-peptide (11.9 +/- 0.7 v 12.9 +/- 0.9 mW/L RBCs, NS, P = .26, n = 12). In another experiment, RBC suspensions were incubated at 37 degrees C in a water bath with or without insulin (50 microU/mL) or C-peptide (6 nmol/L) for 10 minutes. RBC membranes were isolated and Na/K ATPase activity was assessed by measuring inorganic phosphate release at saturating concentrations of all substrates. The results showed that insulin and C-peptide significantly increased RBC Na/K ATPase activity (342 +/- 25, P < .005 and 363 +/- 30, P < .005, respectively v255 +/- 22 nmol Pi x mg protein(-1) x h(-1), n = 14). We conclude that insulin and C-peptide act directly on RBC Na/K ATPase, thus restoring this activity in type 1 diabetic patients. The stimulatory effect of C-peptide observed in vitro on RBC Na/K ATPase activity confirms that C-peptide plays a physiological role. Topics: Adult; C-Peptide; Calorimetry; Diabetes Mellitus, Type 1; Erythrocyte Membrane; Humans; Insulin; Sodium-Potassium-Exchanging ATPase | 2000 |
Comparison of the inhibitory effect of insulin and hypoglycemia on insulin secretion in humans.
Although both insulin and hypoglycemia are known to inhibit endogenous insulin secretion, their potency to suppress insulin secretion has not been directly compared thus far. The serum C-peptide concentration was measured during 28 euglycemic and 28 stepwise hypoglycemic (4.1,3.6, 3.1, and 2.6 mmol/L) clamp experiments using either a low-rate (1.5 mU x min(-1) x kg(-1)) or high-rate (15.0 mU x mU(-1) x kg(-1)) insulin infusion. The experiments lasted 6 hours and were performed in 28 lean healthy men. During both the euglycemic and hypoglycemic clamps, serum insulin was approximately 40-fold higher during the high-rates versus low-rate insulin infusion (euglycemia, 24,029 +/- 1,595 v 543 +/- 34 pmol/L; hypoglycemia, 23,624 +/- 1,587 v 622 +/- 32 pmol/L). Under euglycemic conditions, serum C-peptide decreased from 0.54 +/- 0.04 to 0.41 +/- 0.05 nmol/L during the low-rate insulin infusion (P < .05) and from 0.55 +/- 0.07 to 0.27 +/- 0.09 nmol/L during the high-rate insulin infusion (P < .001). Under hypoglycemic conditions, serum C-peptide decreased from 0.50 +/- 0.03 to 0.02 +/- 0.01 nmol/L during the low-rate insulin infusion (P< .001) and from 0.46 +/- 0.07 to 0.02 +/- 0.01 nmol/L during the high-rate insulin infusion (P< .001). In the euglycemic clamp condition, the high-rate insulin infusion reduced the C-peptide concentration more than the low-rate insulin infusion (P < .05). Independent of the rate of insulin infusion, the decrease in C-peptide was distinctly more pronounced during hypoglycemia versus euglycemia (P < .001). These data indicate that insulin inhibits insulin/C-peptide secretion in a dose-dependent manner. Hypoglycemia is a much stronger inhibitor of insulin secretion than insulin itself. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dose-Response Relationship, Drug; Humans; Hypoglycemia; Insulin; Insulin Secretion; Male | 2000 |
Use of an islet cell antibody assay to identify type 1 diabetic patients with rapid decrease in C-peptide levels after clinical onset. Belgian Diabetes Registry.
To investigate whether the presence of antibody markers at diagnosis could help predict the rapid decrease in residual beta-cell function noted in some, but not all, patients with recent-onset type 1 diabetes.. We measured random C-peptide levels (radioimmunoassay); islet cell cytoplasmic antibodies (ICA) (indirect immunofluorescence); and antibodies against IA-2 protein, 65-kDa glutamate decarboxylase, and insulin (liquid-phase radiobinding assays) in 172 patients <40 years of age with type 1 diabetes. The patients had been consecutively recruited at diagnosis by the Belgian Diabetes Registry and were followed for 2 years.. Two years after diagnosis, random C-peptide levels had decreased significantly (P < 0.001) in ICA+ patients but not in ICA- patients. C-peptide values <50 pmol/ were noted in 88% of patients diagnosed before 7 years of age, in 45% of patients diagnosed between ages 7 and 15 years, and in 29% of patients diagnosed after 15 years of age (P < 0.001). In cases of clinical onset before age 15 years, a rapid decline in random C-peptide values was observed almost exclusively in patients with high-titer ICA (> or =50 Juvenile Diabetes Foundation [JDF] units) at diagnosis (69 vs. 17% in patients with lower ICA titers, P < 0.001). In patients diagnosed after 15 years of age, 36% of patients with ICA titers > or =12JDF units developed low C-peptide levels compared with 14% of patients with ICA titers < 12 JDF units (P < 0.03). Multivariate analysis confirmed that C-peptide levels after 2 years were inversely correlated with ICA levels (P < 0.001) and to a lesser degree positively correlated with age at diagnosis (P < 0.02), regardless of the levels or number of molecular autoantibodies.. Young age at diagnosis and high-titer ICA identify a group of type 1 diabetic patients at high risk of rapidly losing residual beta-cell function. Using these selection criteria, it is possible to better target beta-cell-preserving interventions to patients with or without such rapid progression, depending on the nature of the tested substance. The ICA assay measures clinically relevant antibodies not detected in antibody assays that use recombinant human autoantigens for substrate. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Belgium; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Fluorescent Antibody Technique, Indirect; Glutamate Decarboxylase; Humans; Infant; Insulin Antibodies; Islets of Langerhans; Isoenzymes; Male; White People | 2000 |
The role of C-peptide in the classification of diabetes mellitus.
We investigated twenty-one insulin-using patients, who had all been labelled as having insulin dependent diabetes mellitus (IDDM) or type 1 diabetes. Physicians have been erroneously using the term IDDM loosely to include all diabetics on insulin. The clinical criteria of the National Diabetes Data Group/WHO were used to reclassify these patients. Only thirteen were found to have IDDM and eight non-insulin dependent diabetes mellitus (NIDDM). Using fasting C-peptide values, only five of the thirteen with clinical IDDM truly had IDDM, the others might have maturity onset diabetes of the young (MODY) or diabetes in the young. Of the eight with clinical NIDDM seven had normal to high C-peptide values; the lone patient with low C-peptide values had diabetes diagnosed at age 64 years. We conclude that the clinical classification of diabetes mellitus may be inaccurate and that C-peptide evaluation improves the accuracy of the classification. Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diagnostic Errors; Female; Humans; Insulin; Male; Middle Aged; Prevalence | 2000 |
Parallel changes of proinsulin and islet amyloid polypeptide in glucose intolerance.
Elevated proinsulin secretion and islet amyloid deposition are both features of Type 2 diabetes but their relationship to beta-cell dysfunction is unknown. To determine if islet amyloid polypeptide (IAPP) secretion is disproportionate with other beta-cell products at any stage of glucose intolerance, 116 subjects were studied. Non-diabetic subjects with equivalent body mass index (BMI) were assigned to three groups, (i) normal fasting glucose, fpg<5.5 mmol l(-1); (ii) intermediate fasting glucose, fpg> or =5.5<6.15 mmol l(-1); (iii) impaired fasting glucose (IFG), fpg> or =6.1<7.0 mmol l(-1). Diabetic subjects were divided according to therapy (9 diet, 19 tablet, and 11 insulin). IAPP, C-peptide and proinsulin were measured fasting and at the end of a 1-h glucose infusion. Fasting C-peptide, IAPP and proinsulin were significantly elevated in the IFG group compared with the other non-diabetic groups (P<0.02); fasting IAPP/C-peptide and proinsulin/C-peptide were 1-2% in all non-diabetic groups. Fasting and 1-h proinsulin and proinsulin/C-peptide were higher in diabetic compared with non-diabetic subjects (P<0.01). IAPP and IAPP/C-peptide in diabetic groups were similar to that in non-diabetic subjects but reduced in the insulin-treated group (P<0.01). Proinsulin was disproportionately increased compared with C-peptide and IAPP in Type 2 diabetes particularly in severe beta-cell failure implying more than one concurrent beta-cell pathology. Topics: Amyloid; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucose Intolerance; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islet Amyloid Polypeptide; Longitudinal Studies; Male; Middle Aged; Proinsulin; Reference Values | 2000 |
A case of chronic hepatitis C developing insulin-dependent diabetes mellitus associated with various autoantibodies during interferon therapy.
We report a case of chronic hepatitis C presenting insulin-dependent diabetes mellitus (IDDM) associated with various autoantibodies including possible anti-insulin receptor antibody (AIRA) during interferon (IFN) therapy. A 57-year-old man having chronic hepatitis C virus (HCV) infection with chronic thyroiditis received IFN therapy. The thyroid function was well-controlled by administration of thyroid hormone, although thyroid autoantibodies were positive. At 15 weeks after starting IFN (reaching 530 million units of total dose), marked thirst happened, with increased fasting plasma glucose level (488 mg/dl) and decreased daily urinary C peptide immunoreactivity level (less than 4.2 microg/day). IDDM occurred with anti-nuclear antibody (ANA), anti-DNA antibody and possible AIRA, and thyroid autoantibodies titers increased, but without pancreatic islet cell antibody and anti-glutamic acid decarboxylase antibody. Administration of IFN was stopped and insulin treatment was started, but plasma glucose level was not controlled well. AIRA became negative 2 months later, however, insulin antibody (IA) was positive when tested after 18 months. Serum HCV RNA has been negative, and a normal level of serum transaminase has been observed since IFN therapy. It is likely that IFN therapy induced the immunological disturbance and resulted in occurrence of various autoantibodies and IDDM in the patient. Topics: Antibodies, Antinuclear; Antiviral Agents; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Glycated Hemoglobin; Hepatitis C, Chronic; Humans; Hypothyroidism; Insulin; Insulin Antibodies; Interferon alpha-2; Interferon-alpha; Male; Middle Aged; Receptor, Insulin; Recombinant Proteins; Thyroid Hormones; Transfusion Reaction | 2000 |
Thyroid autoantibodies in Thai type 1 diabetic patients: clinical significance and their relationship with glutamic acid decarboxylase antibodies.
To study the clinical significance of thyroid autoantibodies in Thai patients with type 1 diabetes and their relationship with glutamic acid decarboxylase antibodies (GAD(65)Ab).. Thyroglobulin antibodies (TG-Ab) and thyroid peroxidase antibodies (TPO-Ab) were measured in 50 Thai type 1 diabetic patients. Forty-four patients also had GAD(65)Ab measured. Serum thyrotropin (TSH) was measured in all patients who had no history of thyroid disease regardless of thyroid antibody status. Clinical data including sex, age at onset and duration of diabetes, family history of diabetes, fasting c-peptide levels as well as frequencies of GAD(65)Ab were compared between patients with and without thyroid antibodies. GAD(65)Ab was also measured in 29 non-diabetic patients with hyperthyroid Graves' disease or Hashimoto thyroiditis as a control group.. TG-Ab and TPO-Ab were positive in nine (18%) and 15 (30%) patients, respectively. Eight patients (16%) were positive for both antibodies. Two of 16 patients who were positive for TG-Ab or TPO-Ab had a previous history of hyperthyroidism prior to diabetes onset. Of the remainder, two were newly diagnosed with hyperthyroidism and one was found to have clinical hypothyroidism at the time of the study. None of 34 patients without thyroid antibodies had thyroid dysfunction. Eight patients with positive thyroid antibodies but without clinical thyroid dysfunction and 21 patients without thyroid antibodies were followed for up to 3 years, two patients of the first group developed hypothyroidism, whereas none of the latter developed thyroid dysfunction. The frequency of thyroid dysfunction at the time of initial study was significantly higher in patients with positive thyroid antibodies (3/14 vs. 0/34; P=0.021) and these patients who were initially euthyroid tended to have a higher risk of developing thyroid dysfunction (2/8 vs. 0/21; P=0.069). The frequency of thyroid antibodies was significantly increased in females and in those who had positive GAD(65)Ab. GAD(65)Ab was negative in all of the non-diabetic patients with autoimmune thyroid disease.. About one-fourth of Thai patients with type 1 diabetes without thyroid disease had thyroid antibodies. The frequency of thyroid antibodies was increased in female and in GAD(65)Ab positive patients. The presence of thyroid antibodies is associated with a higher frequency of and may predict a higher risk for thyroid dysfunction in Thai type 1 diabetic patients. Topics: Adult; Age of Onset; Asian People; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Graves Disease; Humans; Iodide Peroxidase; Isoenzymes; Male; Thailand; Thyroglobulin; Thyrotropin | 2000 |
Functional rest through intensive treatment with insulin and potassium channel openers preserves residual beta-cell function and mass in acutely diabetic BB rats.
Diazoxide and the diazoxide-analogue, NNC 55-0118, are potassium channel openers that interfere with insulin secretion from beta-cells. In vitro, we show that these two drugs inhibit insulin release from diabetes-resistant BB rat islets cultured at either low or high glucose concentration and cause an intracellular accumulation of insulin with high glucose. Preservation of beta-cells was investigated in newly diabetic BB rats treated with insulin implants from day 0-8 under oral diazoxide, NNC 55-0118 or solvent gavage once a day from day 0-7. Three of eight rats (37.5%) treated with diazoxide and three of ten (30%) treated with NNC 55-0118 retained near normal C-peptide responses when challenged with glucose/arginine on day 9, whereas none of eight (0%) solvent-treated rats showed a C-peptide response. Immunohistochemical staining for insulin and glucagon showed that all the C-peptide responding rats had insulin-positive cells in their islets. In contrast, islets from non-responding rats displayed marked inflammation or end-stage lesions. Furthermore, rats with C-peptide response and treated with NNC 55-0118 exhibited only minimal signs of islet inflammation, whereas C-peptide responding diazoxide-treated rats had low level islet inflammation. These results imply that it is conceivable to preserve residual beta-cells at diabetes onset by induction of target cell rest with potassium channel openers and continuous insulin treatment. Topics: Animals; Arginine; Blood Glucose; C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Diazoxide; Glucagon; Glucose Tolerance Test; Insulin; Insulin Secretion; Islets of Langerhans; Kinetics; Potassium Channels; Rats; Rats, Inbred BB; Rats, Inbred WF | 2000 |
Distribution of autoantibodies to glutamic acid decarboxylase across the spectrum of diabetes mellitus seen in South Africa.
This study investigated the association between glutamic acid decarboxylase antibodies (GAD-AB) and Type 1, Type 2, pancreatic and lipoatrophic diabetes mellitus (DM) in South African patients.. Four groups were selected: group A, 100 Black Type 1 DM patients (age at onset < 35 years, body mass index (BMI) < 27 kg/m2 and insulin dependent within 1 year of presentation); group B, 80 Black Type 2 DM patients (age at onset > 35 years, BMI > 27 kg/m2 and controlled on oral hypoglycaemic agents for at least 1 year after presentation); group C, 10 patients of varying ethnicity with DM or impaired glucose tolerance secondary to chronic pancreatitis; group D, five patients of varying ethnicity with DM associated with total lipodystrophy. Fifty healthy Black control subjects were also studied (group E). Serum GAD-AB and random C-peptide levels were measured by radioimmunoassay.. Mean C-peptide concentration was significantly lower in Type 1 DM patients than Type 2 DM patients (P < 0.00001). Forty-four patients with Type 1 DM were GAD-AB-positive compared to two patients with Type 2 DM. Two control subjects were also GAD-AB-positive. No patient in the other groups had a titre > 1 U/ml. Type 1 DM patients who were GAD-AB-positive did not differ from those who were GAD-AB-negative for age at onset, duration of DM or C-peptide concentrations.. Auto-immune beta-cell destruction has an important role in the pathogenesis of Type 1 DM amongst African patients. However, Type 2 African DM patients and other diabetes subtypes are largely GAD-AB-negative. Topics: Adult; Autoantibodies; Black People; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Male; Middle Aged; Pancreatic Diseases; Radioimmunoassay; South Africa | 2000 |
Genetic, autoimmune, and clinical characteristics of childhood- and adult-onset type 1 diabetes.
To assess whether there are any differences in genetic, autoimmune, or clinical features between type 1 diabetes presenting in childhood and that diagnosed later.. We studied 352 individuals (252 children and adolescents <20 years of age and 100 adults > or =20 years of age) manifesting clinical signs of type 1 diabetes over a period of 7.5 years at a university hospital in northern Finland with a primary catchment area population of approximately 300,000. The patients were analyzed for susceptible and protective HLA-DQB1 alleles (*02, *0302, *0301, *0602, *0603, and *0604), islet cell antibodies (ICA), insulin autoantibodies, and antibodies to GAD and IA-2 (IA-2A). Their clinical symptoms and signs were recorded at diagnosis.. The adult patients carried the high-risk DQB1*02/0302 genotype less frequently than the children and more often had protective genotypes. They also had a decreased frequency of all 4 single autoantibody specificities and of multiple (> or =3) autoantibodies. The proportion of patients testing negative for all autoantibodies was lower among the children than among the adults. IA-2A were associated with the DQB1*0302/x genotype in both the children and adults, and the same held true for ICA among the adults. The adults were characterized by a higher proportion of males, a longer duration of symptoms, and a lower frequency of infections during the preceding 3 months. In addition, they had a higher relative body weight on admission and milder signs of metabolic decompensation (higher pH, base excess, and bicarbonate concentrations) and a lower glycated hemoglobin level at diagnosis than the children.. Clinical manifestation of type 1 diabetes before the age of 20 years is associated with a strong HLA-defined genetic disease susceptibility, an intensive humoral immune response to various beta-cell antigens, a higher frequency of preceding infections, and a shorter duration of symptoms and more severe metabolic decompensation at diagnosis. Taken together, these observations suggest that the age at clinical onset of type 1 diabetes is determined by the intensity of the beta-cell-destructive process, which is modulated by both genetic and environmental factors. Topics: Adolescent; Adult; Age of Onset; Alleles; Autoantibodies; Blood Glucose; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Finland; Glutamate Decarboxylase; Glycated Hemoglobin; Histocompatibility Antigens Class II; HLA-DQ Antigens; HLA-DQ beta-Chains; Hospitals, University; Humans; Islets of Langerhans; Male | 2000 |
Insights from a successful case of intrahepatic islet transplantation into a type 1 diabetic patient.
We report a case of long-term (>4 yr) successful intrahepatic islet transplantation into a type 1 diabetic patient chronically immunosuppressed for a prior kidney graft. The exogenous insulin requirement decreased progressively after transplantation, and insulin treatment was withdrawn at 6 months. Glycosylated hemoglobin levels were in the normal range at 1 and 2 yr (5.3%) and increased slightly above the upper normal limit at 3 and 4 yr (6.3% and 6.4%). Fasting C peptide levels remained stable during the entire follow-up, but the proinsulin to insulin ratios increased dramatically at yr 3. Glycemic levels after an oral glucose tolerance test showed a diabetic profile at 1 yr, a normal profile at 2 yr, and an impaired glucose tolerance profile at 3 yr. Intravenous glucose tolerance test-induced first phase insulin release, present at 1 and 2 yr, disappeared at 3 yr. Diabetes-related autoantibodies (islet cell antibodies, glutamic acid decarboxylase antibodies, and tyrosine phosphatase-like protein antibodies) were undetectable before transplantation and remained so during the entire follow-up. The patient died of myocardial infarction 50 months after transplantation while she was still in good metabolic control (glycosylated hemoglobin, <6.8%) in the absence of exogenous insulin administration. The autoptic liver showed well granulated islets, richly vascularized and without evidence of lympho-mononuclear cell infiltration. The morphometrically extrapolated intrahepatic beta-cell mass was 99.9 mg. In conclusion, this successful islet graft showed a bell-shaped clinical effect, maximal at 2 yr after transplantation, followed by a slow progressive decline. The absence of allo- and autoreactivities against the transplanted islets points to a nonimmune-mediated beta-cell loss as the cause of graft functional deterioration. Topics: Adult; Blood Glucose; C-Peptide; Cell Transplantation; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Proinsulin | 2000 |
Serum leptin levels in type 1 diabetic and obese children: relation to insulin levels.
To compare serum leptin levels in type 1 diabetic and obese children.. We studied serum leptin levels in 35 type 1 diabetic, 32 obese, and 35 healthy children. Seven of 35 were new-onset diabetics with ketoacidosis. C-peptide (CPE) levels were used for estimating insulin secretion.. Serum leptin levels were lower in diabetics than in controls (p<0.001). Obese children had higher leptin and CPE levels than diabetics and controls. In new-onset diabetics, 1 month insulin treatment did not cause any change in leptin levels (p>0.05). Leptin was correlated positively with body mass index and CPE (p<0.001) and inversely with glucose (p = 0.001) and HbA1c (p<0.05) in the combined group. HbA1c and gender were the independent predictors of leptin in diabetic children (p<0.01).. Low serum leptin levels in type 1 diabetic children may be due to chronic insulin deficiency related with their metabolic control. Leptin and insulin may have complementary roles in maintaining a stable body weight. Topics: Adolescent; Body Mass Index; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Leptin; Male; Matched-Pair Analysis; Obesity; Statistics as Topic | 2000 |
Is the paradoxical first trimester drop in insulin requirement due to an increase in C-peptide concentration in pregnant Type I diabetic women?
Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, First | 2000 |
Growth and insulin-like growth factors (IGFs) in children with insulin-dependent diabetes mellitus at the onset of disease: evidence for normal growth, age dependency of the IGF system alterations, and presence of a small (approximately 18-kilodalton) IGF
Data on growth of children with insulin-dependent diabetes mellitus (IDDM) before the onset of disease are conflicting, and although the insulin-like growth factor (IGF) system has almost invariably been found altered at diagnosis, most of previous studies are affected by the small number of patients investigated. We studied 60 IDDM children at the onset of disease, comparing their stature with target height, normal growth standards, and height of 102 sex- and age-matched controls. Furthermore, we assessed serum IGF-I, IGF-II, and IGF-binding protein-3 (IGFBP-3) levels and IGFBP-3 circulating forms. IDDM children were subdivided into 2 groups according to an age above (n = 26) or below (n = 34) 6 yr. The values of endocrine variables of diabetics older than 6 yr were compared with those of 34 age-matched controls. Although the height of diabetics was higher than growth reference values (mean height +/- SD, 0.64+/-1.4 z-score) and their target height (mean target height +/- SD, 0.1+/-0.84 z-score; P < 0.005), no significant difference in height was found between IDDM children and controls (mean height +/- SD, 0.64+/-0.95 z-score) even analyzing the 2 age groups separately. Overall, IDDM children showed reduced levels of IGF-I (mean +/- SD, -0.65+/-1.9 z-score) and normal levels of IGF-II (mean +/- SD, -0.05+/-1.2 z-score) and IGFBP-3 (mean +/- SD, -0.06+/-1.2 z-score). However, whereas patients younger than 6 yr showed normal values of IGF-I, IGF-II, and IGFBP-3, these peptides were significantly reduced in older subjects compared with either younger IDDM children or controls (P < 0.01). IGFBP-3 immunoblot analysis revealed the presence of an approximately 18-kDa fragment of IGFBP-3 in addition to the major approximately 29-kDa fragment and the intact form (approximately 42-39 kDa) in 46 of 60 IDDM patients, whereas the approximately 18-kDa band was absent in all 34 control sera. No relationship was found between the endocrine variables and stature at diagnosis. In conclusion, our results indicate that IDDM children at the onset of disease are not taller than healthy peers and have increased IGFBP-3 proteolytic activity. Finally, although the IGF system is normal in younger IDDM children, older patients have reduced IGF levels. Topics: Age of Onset; Body Height; C-Peptide; Case-Control Studies; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Growth; Humans; Hydrocortisone; Insulin-Like Growth Factor Binding Protein 3; Insulin-Like Growth Factor I; Insulin-Like Growth Factor II; Male; Molecular Weight; Reference Values | 2000 |
Simultaneous peripubertal onset of multireactive autoimmune diseases with an unusual long-lasting remission of type 1 diabetes mellitus.
Although it is well known that patients with type 1 diabetes mellitus are susceptible to other autoimmune diseases, the simultaneous occurrence of clustered distinct autoimmune diseases is uncommon. We report a 16-year-old girl, previously diagnosed as having coeliac disease and IgA deficiency, who at 13 years of age developed a clustering of distinct autoimmune diseases, including type 1 diabetes mellitus, rheumatoid arthritis (RA) and euthyroid autoimmune thyroiditis, eventually resulting in a simultaneous long-term remission. The clinical picture was associated with a functional immunodeficiency characterized by a defect in proliferative responses to T cell predominant mitogens and a normal response to the B cell predominant mitogen. In addition, the T cell activation markers HLA-DR, IL-2 receptor and transferrin receptor) were not upregulated. The clinical course of this immunodeficiency paralleled the outcome of the autoimmune diseases. After the abrupt onset, spontaneous clinical remission of both diabetes mellitus and RA was observed. Insulin was first reduced in dose and then discontinued completely at 15 months, in the presence of normal C peptide secretion and normal metabolic control (HbA1c 5.8%). Anti-glutamate decarboxylase (GAD65) and anti-IA-2 antibodies remained persistently high. During the remission phase a normalization of the functional immune defect was observed. The gradual resolution of the multisystemic diseases as well as the normalization of immune function in our patient is unusual. This case may be of considerable value in furthering our knowledge of the immunological mechanisms implicated in these rare multireactive syndromes. Topics: Adolescent; Arthritis, Rheumatoid; Autoantibodies; C-Peptide; Celiac Disease; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Glucose Tolerance Test; Humans; IgA Deficiency; Mitogens; Remission, Spontaneous; Thyroiditis, Autoimmune; Up-Regulation | 2000 |
Four-year results of pancreas transplantation in Taiwan.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drug Therapy, Combination; Female; Follow-Up Studies; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Male; Pancreas Transplantation; Postoperative Complications; Retrospective Studies; Taiwan; Time Factors | 2000 |
Prognostic factors for the course of beta cell function in autoimmune diabetes.
This study presents a 2-yr follow-up of 281 patients, aged 15-34 yr, diagnosed with diabetes between 1992 and 1993. At diagnosis, 224 (80%) patients were positive for at least one of the following autoantibodies: islet cell antibodies (ICAs), glutamic acid decarboxylase antibodies (GADAs), or tyrosine phosphatase antibodies (IA-2As); the remaining 57 (20%) patients were negative for all three autoantibodies. At diagnosis, C-peptide levels were lower (0. 27; 0.16-0.40 nmol/L) in autoantibody-positive patients compared with autoantibody-negative patients (0.51; 0.28-0.78 nmol/L; P: < 0. 001). After 2 yr, C-peptide levels had decreased significantly in patients with autoimmune diabetes (0.20; 0.10-0.37 nmol/L; P: = 0. 0018), but not in autoantibody-negative patients. In patients with autoimmune diabetes, a low initial level of C-peptide (odds ratio, 2. 6; 95% confidence interval, 1.7-4.0) and a high level of GADAs (odds ratio, 2.5; 95% confidence interval, 1.1-5.7) were risk factors for a C-peptide level below the reference level of 0.25 nmol/L 2 yr after diagnosis. Body mass index had a significant effect in the multivariate analysis only when initial C-peptide was not considered. Factors such as age, gender, levels of ICA or IA-2A or insulin autoantibodies (analyzed in a subset of 180 patients) had no effect on the decrease in beta-cell function. It is concluded that the absence of pancreatic islet autoantibodies at diagnosis were highly predictive for a maintained beta-cell function during the 2 yr after diagnosis, whereas high levels of GADA indicated a course of decreased beta-cell function with low levels of C-peptide. In autoimmune diabetes, an initial low level of C-peptide was a strong risk factor for a decrease in beta-cell function and conversely high C-peptide levels were protective. Other factors such as age, gender, body mass index, levels of ICA, IA-2A or IAA had no prognostic importance. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Biomarkers; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Islets of Langerhans; Male; Prognosis; Sex Characteristics; Time Factors | 2000 |
Random C-peptide in the classification of diabetes.
To clarify whether random C-peptide is a valuable test in the classification of diabetes.. All C-peptide measurements conducted in the diabetic population of Skaraborg (280,539 inhabitants and 3.2% diabetes) between 1995 and 1998 (3,115 samples) were considered, but only patients with well-defined diabetes type (1,449 samples from 1,093 patients) were analyzed for the correlation between diabetes type and C-peptide concentration. Serum C-peptide was measured after fasting over night (fCP), after glucagon stimulation (gCP), and randomly (rCP) without considering previous meals at an ordinary visit to the diabetic clinic (rCP). Receiver Operating Characteristic (ROC) curves were constructed to illustrate the power of the different C-peptide protocols and to determine the optimal cut-off values.. Although all three tests had high discriminative power, the ROC curves demonstrated that rCP was superior to fCP and gCP in discriminating type 1 from type 2 diabetes. The optimal cut-off value for rCP was 0.50 nmol/L, for fCP 0.42 nmol/L, and for gCP 0.60 nmol/L.. rCP is more powerful than fCP and gCP in distinguishing type 1 from type 2 diabetes and can therefore be recommended as a classification tool, particularly in outpatients. Topics: Adolescent; Adult; Aged; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Humans; Middle Aged; Retrospective Studies; ROC Curve | 2000 |
Postabsorptive muscle protein metabolism in type 1 diabetic patients after pancreas transplantation.
Insulin was shown to induce protein anabolism in vivo mainly by inhibiting proteolysis. Heterotopic pancreas transplantation in type 1 diabetes mellitus is characterized by peripheral hyperinsulinemia due to systemic rather than portal insulin delivery. Therefore, we studied the postabsorptive muscle protein metabolism in type 1 diabetic patients with or without pancreas transplantation. The forearm balance technique was performed in 9 type 1 diabetic patients on exogenous insulin treatment, in 4 type 1 diabetic patients following successful pancreas transplantation and in 6 healthy volunteers. Labelled leucine and phenylalanine were infused to quantify whole-body and muscle protein synthesis, respectively. In the postabsorptive state, whole-body protein synthesis (leucine kinetics) was similar in pancreas-transplanted patients and controls. In contrast, muscle protein synthesis tended to be less negative in pancreas-transplanted patients with respect to type 1 diabetic patients and healthy volunteers. The present data suggest that recipients with peripheral insulin delivery and chronic hyperinsulinemia are characterized by a preferential stimulation of protein synthesis in muscle rather than in the splanchnic district. When insulin was infused acutely, while maintaining euglycemia, the whole-body and muscle protein synthesis rates were approximately halved in type 1 diabetic patients with and without pancreas transplantation. We conclude that pancreas transplantation is able to normalize basal and insulin-stimulated protein metabolism. Chronic hyperinsulinemia counteract steroid-induced protein degradation by means of a mild, but persistent stimulation of muscle protein synthesis. Topics: Adult; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Energy Intake; Forearm; Glycated Hemoglobin; Humans; Immunosuppressive Agents; Insulin; Leucine; Middle Aged; Muscle Proteins; Muscle, Skeletal; Pancreas Transplantation; Phenylalanine; Prednisone; Protein Biosynthesis; Proteins; Reference Values; Regional Blood Flow | 2000 |
Estimating prevalence of type 1 and type 2 diabetes in a population of African Americans with diabetes mellitus.
The pathogenesis, treatment, and outcomes of type 1 and type 2 diabetes differ. Current surveys derive population-based estimates of diabetes prevalence by type using limited clinical information and applying classification rules developed in white populations. How well these rules perform when deriving similar estimates in African American populations is unknown. For this study, data were collected on a group of African Americans with diabetes who enrolled at the Diabetes Unit of Grady Memorial Hospital in Atlanta, Georgia, from April 16, 1991, to November 1, 1996. The data were used to develop some simple classification rules for African Americans based on a classification tree and a logistic regression model. Sensitivities and specificities, in which fasting C-peptide was used as the gold standard, were determined for these rules and for two current rules developed in mostly white, non-Hispanic populations. Rules that yielded precise (minimum variance unbiased) estimates of the prevalence of type 1 diabetes were preferred. The authors found that a rule based on the logistic regression model was best for estimating type 1 prevalences ranging from 1% to 17%. They concluded that simple classification rules can be used to estimate prevalence of diabetes by type in African American populations and that the optimal rule differs somewhat from the current rules. Topics: Adult; Aged; Black People; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Logistic Models; Male; Middle Aged; Prevalence | 1999 |
C-peptide potentiates the vasoconstrictor effect of neuropeptide Y in insulin-dependent diabetic patients.
Recent findings suggest that proinsulin C-peptide improves renal and nerve function as well as microcirculation in patients with insulin-dependent diabetes possibly by stimulating Na-K+-ATPase activity. Furthermore, in vitro studies on proximal rat renal tubule cells show that the effect of C-peptide on Na+, K+-ATPase activity is potentiated in the presence of the vasoconstrictor peptide neuropeptide Y. The aim of the present study was to examine whether the effects of neuropeptide Y on resting forearm blood flow in insulin-dependent patients is altered in the presence of C-peptide. Forearm blood flow was measured by a plethysmographic method in eight insulin-dependent patients and six healthy control subjects. Neuropeptide Y (20, 200 and 2000 pmol min(-1)) was infused into the brachial artery before and during an i.v. infusion of C-peptide (5 pmol kg(-1) min(-1)). Basal blood flow was 36.7 +/- 2.2 mL min(-1) L(-1) tissue. It decreased in a dose dependent manner by 11 +/- 2, 18 +/- 3 and 25 +/- 3%, respectively, during infusion of neuropeptide Y. Administration of C-peptide increased basal blood flow by 25 +/- 6%, to 46.3 +/- 3.5 mL min(-1) L(-1) tissue (P < 0.01) and forearm glucose uptake by 76 +/- 34% (P < 0.05). Infusion of the three doses of neuropeptide Y during administration of C-peptide decreased forearm blood flow by 14 +/- 4, 22 +/- 3 and 42 +/- 4%. There was a significant difference (43%, P < 0.001) between the reduction in blood flow evoked by the high dose (2000 pmol min(-1)) of neuropeptide Y before and during C-peptide infusion. Similar differences were also obtained when data were calculated as changes in vascular resistance. C-peptide did not affect resting forearm blood flow or the response to neuropeptide Y in healthy controls. In conclusion, the present data demonstrate that C-peptide increases resting forearm blood flow and augments the vasoconstrictor effects of neuropeptide Y in insulin-dependent patients. Topics: Adult; Blood Flow Velocity; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Drug Synergism; Female; Forearm; Humans; Infusions, Intra-Arterial; Infusions, Intravenous; Male; Neuropeptide Y; Plethysmography; Vasoconstriction | 1999 |
Auto- and alloimmune reactivity to human islet allografts transplanted into type 1 diabetic patients.
Allogeneic islet transplantation can restore an insulin-independent state in C-peptide-negative type 1 diabetic patients. We recently reported three cases of surviving islet allografts that were implanted in type 1 diabetic patients under maintenance immune suppression for a previous kidney graft. The present study compares islet graft-specific cellular auto- and alloreactivity in peripheral blood from those three recipients and from four patients with failing islet allografts measured over a period of 6 months after portal islet implantation. The three cases that remained C-peptide-positive for >1 year exhibited no signs of alloreactivity, and their autoreactivity to islet autoantigens was only marginally increased. In contrast, rapid failure (<3 weeks) in three other cases was accompanied by increases in precursor frequencies of graft-specific alloreactive T-cells; in one of them, the alloreactivity was preceded by a sharply increased autoreactivity to several islet autoantigens. One recipient had a delayed loss of islet graft function (33 weeks); he did not exhibit signs of graft-specific alloimmunity, but developed a delayed increase in autoreactivity. The parallel between metabolic outcome of human beta-cell allografts and cellular auto- and alloreactivity in peripheral blood suggests a causal relationship. The present study therefore demonstrates that T-cell reactivities in peripheral blood can be used to monitor immune mechanisms, which influence survival of beta-cell allografts in diabetic patients. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Histocompatibility Testing; Humans; Islets of Langerhans Transplantation; Isoantibodies; Lymphocyte Activation; Male; Middle Aged; Time Factors; Transplantation, Homologous | 1999 |
Management of the young child with diabetes mellitus: how do we measure success?
Topics: Adolescent; Age Factors; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Hypoglycemia; Infant; Islets of Langerhans; Randomized Controlled Trials as Topic; Risk | 1999 |
Euglycaemic hyperinsulinaemia does not affect gastric emptying in type I and type II diabetes mellitus.
Hyperglycaemia slows gastric emptying in both normal subjects and patients with diabetes mellitus. The mechanisms mediating this effect, particularly the potential role of insulin, are uncertain. Hyperinsulinaemia has been reported to slow gastric emptying in normal subjects during euglycaemia. The purpose of this study was to evaluate the effect of euglycaemic hyperinsulinaemia on gastric emptying in Type I (insulin-dependent) and Type II (noninsulin-dependent) diabetes mellitus. In six patients with uncomplicated Type I and eight patients with uncomplicated Type II diabetes mellitus, measurements of gastric emptying were done on 2 separate days. No patients had gastrointestinal symptoms or cardiovascular autonomic neuropathy. The insulin infusion rate was 40 mU x m(-2) x min(-1) on one day and 80 mU x m(-2) x min(-1) on the other. Gastric emptying and intragastric meal distribution were measured using a scintigraphic technique for 3 h after ingestion of a mixed solid/liquid meal and results compared with a range established in normal volunteers. In both Type I and Type II patients the serum insulin concentration had no effect on gastric emptying or intragastric meal distribution of solids or liquids. When gastric emptying during insulin infusion rates of 40 mU x m(-2) x min(-1) and 80 mU x m(-2) x min(-1) were compared the solid T50 was 137.8+/-24.6 min vs. 128.7+/-24.3 min and liquid T50 was 36.7+/-19.4 min vs. 40.4+/-15.7 min in the Type I patients; the solid T50 was 94.9+/-19.1 vs. 86.1+/-10.7 min and liquid T50 was 21.8+/-6.9 min vs. 21.8+/-5.9 min in the Type II patients. We conclude that hyperinsulinaemia during euglycaemia has no notable effect on gastric emptying in patients with uncomplicated Type I and Type II diabetes; any effect of insulin on gastric emptying in patients with diabetes is likely to be minimal. Topics: Adult; Amyloid; Blood Glucose; C-Peptide; Cholecystokinin; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gastric Emptying; Glucagon; Glucagon-Like Peptide 1; Glucose Clamp Technique; Glycated Hemoglobin; Humans; Hyperinsulinism; Hypoglycemic Agents; Infusions, Intravenous; Insulin; Islet Amyloid Polypeptide; Male; Peptide Fragments; Protein Precursors | 1999 |
Evaluation of the pancreas reserve in siblings of type I diabetic children.
The purpose of this study was to determine the pancreas reserve in siblings of diabetic patients by screening islet cell antibodies (ICA), insulin auto antibodies (IAA), reduced C-peptide levels, first-phase insulin release and the derangement of cellular immunity (reduction of natural killer cells, abnormality of the T cell subpopulations).. Twelve siblings (aged 9.3 +/- 2.8 years) of diabetic children were evaluated and results were compared with the control group (12.1 +/- 3.5 years). For siblings of the diabetic children, fasting, post-prandial and glucagon response C-peptide mean values were 2.2 +/- 1.2, 7.2 +/- 7.1 and 5.3 +/- 3.6 ng/mL, respectively, while in the control group they were 1.5 +/- 0.8, 3.6 +/- 2.0 and 5.1 +/- 2.9 ng/mL, respectively. There were no differences between the two groups. In 33%, postprandial C-peptide, and in 11% of the siblings, glucagon response C-peptide values were exaggerated. In siblings the first phase insulin release (FPIR) during an intravenous glucose tolerance test was 128.5 +/- 96.6 (above the 50th percentile) and stimulated insulin release (SIR) was 103.8 +/- 92.5 (above 25th percentile). Sibling values were significantly lower than the control group (FPIR 152.4 +/- 42.5, P = 0.01; SIR 134.9 +/- 38.2, P = 0.01). Values for FPIR (in two children) and SIR (three cases) were below the 5th percentile. In one, FPIR and SIR levels were both below the 1st percentile. Islet cell antibodies and IAA were also present in this subject. Treatment with nicotinamide was started in the cases with FPIR and SIR below the 5th percentile. We did not observe overt diabetic symptoms during the follow-up period of more than 3 years.. We recommend that borderline insulin secretion be tested annually in siblings who show insufficient FPIR. Topics: Adolescent; Antibodies; C-Peptide; Case-Control Studies; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Killer Cells, Natural; Male; Pancreas; Pedigree; T-Lymphocyte Subsets | 1999 |
Continuous subcutaneous insulin injection for a case of mitochondrial cytopathy with diabetes mellitus requiring a large amount of insulin.
Topics: Adolescent; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Infusions, Parenteral; Insulin; Mitochondrial Myopathies | 1999 |
The effect of human proinsulin C-peptide on erythrocyte deformability in patients with Type I diabetes mellitus.
In recent years, evidence has arisen that proinsulin C-peptide exerts biological effects especially on microcirculation, e.g. C-peptide has been shown to increase skin microcirculation in patients with Type I (insulin-dependent) diabetes mellitus and to activate endothelial nitric oxide synthase. This study aimed to investigate the influence of pro-insulin C-peptide on erythrocyte deformability which was assessed by means of laser diffractoscopy.. Blood samples from healthy control subjects (n = 10) and Type I diabetic patients (n = 15) completely deficient of C-peptide were analysed at shear stresses ranging from 0.3 to 30 Pa.. Erythrocyte deformability was lower in the group of Type I diabetic patients than in the control subjects. Preincubation of the diabetic blood samples with various concentrations of human proinsulin C-peptide for 8 h restored the deformability of erythrocytes, almost reaching the values of control samples. In contrast, proinsulin C-peptide did not modify the erythrocyte deformability of control subjects.. We conclude that proinsulin C-peptide is able to ameliorate the impaired deformability of erythrocytes in Type I diabetic patients and we hypothesise that this effect is mediated by restoration of Na(+)-K(+)-ATPase activity, which is known to be attenuated in diabetic patients. Topics: C-Peptide; Diabetes Mellitus, Type 1; Enzyme Inhibitors; Erythrocyte Deformability; Erythrocytes; Humans; Lasers; Ouabain; Sodium-Potassium-Exchanging ATPase | 1999 |
Plasma and interstitial glucose dynamics after intravenous glucose injection: evaluation of the single-compartment glucose distribution assumption in the minimal models.
Recent experimental evidence suggests that estimates of glucose effectiveness (S(G)) from the minimal model of unlabeled glucose disappearance (Cold-MM) are in error. The single-compartment glucose distribution assumption embedded in the model has been indicated as a possible source of error. In this study, to directly examine the single-compartment assumption, we measured plasma and interstitial glucose concentrations after intravenous glucose injection. Additionally, we compared the accuracy of the estimates of glucose effectiveness from the Cold-MM and the single-compartment tracer minimal model (Hot-MM). Paired labeled intravenous glucose tolerance tests (IVGTTs) were performed in each of six C-peptide-negative type 1 diabetic subjects. Two different insulin infusion protocols were used: an infusion at constant basal rates and an infusion at variable rates to mimic a normal insulin response. During the labeled IVGTT with basal insulin infusion, the microperfusion technique was employed to sample adipose tissue interstitial fluid. Marked differences between the plasma and interstitial dynamics of (cold) glucose were observed during the first 22 min after glucose injection. These results suggest that the requirements for a single-compartment representation of glucose kinetics are not satisfied during at least the first 22 min of an IVGTT. Data from the labeled IVGTT with normal insulin response were used to identify the minimal-model parameters. The measure of S(G) derived using the Cold-MM was 3.44-fold higher than the direct measure obtained from the labeled IVGTT with basal insulin infusion (0.0179+/-0.0027 vs. 0.0052+/-0.0010 min(-1), P<0.01). The measure of glucose effectiveness (S(G)*) derived by the Hot-MM was 1.36-fold higher than the direct measure available from the labeled IVGTT with basal insulin infusion (0.0079+/-0.0013 vs. 0.0058+/-0.0004 min(-1), P>0.26). These results suggest that the Hot-MM is more appropriate for the evaluation of glucose effectiveness than the Cold-MM. Topics: Adult; Blood Glucose; C-Peptide; Deuterium; Diabetes Mellitus, Type 1; Extracellular Space; Female; Glucose; Glucose Tolerance Test; Humans; Injections, Intravenous; Insulin; Kinetics; Male; Mathematics; Middle Aged; Models, Biological; Sodium | 1999 |
Hypoglycemia associated with maprotiline in a patient with type 1 diabetes.
Topics: Adult; Antidepressive Agents, Second-Generation; Blood Glucose; C-Peptide; Depressive Disorder; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Hypoglycemia; Hypoglycemic Agents; Insulin; Maprotiline | 1999 |
Immunological abnormalities in islets at diagnosis paralleled further deterioration of glycaemic control in patients with recent-onset Type I (insulin-dependent) diabetes mellitus.
To determine whether the clinical heterogeneity observed in the development of Type I (insulin-dependent) diabetes mellitus correlates with immunohistochemical differences observed at diagnosis.. Patients (n = 17) with recent-onset diabetes clinically considered to be insulin dependent (Type I), underwent pancreatic biopsy for immunohistological analysis. These patients were divided into two groups based on the presence or absence of islet immunological abnormalities (insulitis or hyperexpression of MHC class I antigens or both). The patients were also HLA typed and tested for islet cell antibodies and antibodies to glutamic acid decarboxylase (GAD-Ab). All patients were followed monthly for 2 years and their fasting plasma glucose, haemoglobin A1c and daily insulin doses were recorded. The clinical course of patients with islet immunological abnormalities was compared with that of patients without those abnormalities.. Patients with and without islet immunological abnormalities did not differ with regard to HLA type or islet cell antibodies. Antibodies to glutamic acid decarboxylase correlated with the presence of insulitis and MHC class I hyperexpression. These local immunological abnormalities were also associated with higher haemoglobin A1c values (p < 0.05) and a trend towards greater insulin requirements. Further, patients with the islet abnormalities had higher fasting plasma glucose concentrations 2 years after the biopsy than at the time of the biopsy (p < 0.05).. The heterogeneous clinical course observed following diagnosis in patients with Type I diabetes correlates with islet immunological abnormalities. Insulitis and hyperexpression of MHC class I correlate with deteriorating glycaemic control. Topics: Adolescent; Adult; Autoantibodies; Autoimmune Diseases; Biopsy; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Histocompatibility Antigens Class I; Histocompatibility Antigens Class II; Histocompatibility Testing; Humans; Inflammation; Islets of Langerhans; Male; Middle Aged | 1999 |
Three new mutations in the hepatocyte nuclear factor-1alpha gene in Japanese subjects with diabetes mellitus: clinical features and functional characterization.
Mutations in the hepatocyte nuclear factor-1alpha gene are a common cause of the type 3 form of maturity-onset diabetes of the young. We examined the clinical features and molecular basis of hepatocyte nuclear factor-1alpha (HNF-1alpha) diabetes.. Thirty-seven Japanese subjects with early onset Type II (non-insulin-dependent) diabetes mellitus and 45 with Type I (insulin-dependent) diabetes mellitus were screened for mutations in this gene. Functional properties of mutant HNF-1alpha were also investigated.. Three new mutations [G415R, R272C and A site of the promoter (+ 102G-to-C)] were found. Insulin secretion was impaired in the three subjects. Insulin and glucagon secretory responses to arginine in the subject with the R272C mutation were also diminished. Molecular biological studies indicated that the G415R mutation generated a protein with about 50% of the activity of wild-type HNF-1alpha. The R272C mutation had no transactivating or DNA binding activity and acted in a dominant negative manner. The + 102 G-to-C mutation in the A site of the promoter activity was associated with an increase in promoter activity and it had 42-75% more activity than the wild-type sequence.. Mutations in the HNF-1alpha gene may affect the normal islet function by different molecular mechanisms. Topics: Adult; Arginine; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; DNA; DNA-Binding Proteins; Female; Glucagon; Glucose Tolerance Test; Hepatocyte Nuclear Factor 1; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 1-beta; Humans; Insulin; Insulin Secretion; Male; Middle Aged; Mutation; Nuclear Proteins; Promoter Regions, Genetic; Transcription Factors | 1999 |
Clinical, immunological, and genetic heterogeneity of diabetes in an Italian population-based cohort of lean newly diagnosed patients aged 30-54 years. Piedmont Study Group for Diabetes Epidemiology.
In lean diabetic patients, the presentation of the disease does not allow one to easily distinguish between type 1 and type 2. Aims of this study were to describe clinical, immunological, and genetic features of lean newly diagnosed diabetic patients.. A population-based cohort of 130 lean (BMI < 25 kg/m2) newly diagnosed patients, aged 30-54 years, was identified among residents of the province of Turin. Islet cell antibodies (ICAs), anti-GAD, fasting and glucagon-stimulated C-peptide values, and HLA DQA1-DQB1 susceptibility genotypes were assessed within 2 months of the diagnosis.. A total of 45 (34.6%) and 29 (22.3%) patients were, respectively, ICA+ and anti-GAD+, with 15 (11.5%) having both antibodies. In 59 patients, ICAs and/or anti-GAD antibodies were detected, giving a high prevalence of autoimmunity (45.4%, 95% Cl 36.8-54.0); relative to patients without markers (n = 71), they were younger (40.8 +/- 7.5 vs. 45.0 +/- 6.5 years, P < 0.001) and showed lower values of fasting C-peptide (0.56 +/- 0.33 vs. 0.79 +/- 0.41 nmol/l, P < 0.001) and stimulated C-peptide (1.03 +/- 0.56 vs. 1.42 +/- 0.69 nmol/l, P < 0.001). The lowest stimulated C-peptide values were found in patients with both ICA and anti-GAD antibodies. Frequencies of adult-onset type 1 and type 2 diabetes were, respectively, 49.2 and 50.8%. Clinical and genetic features were not useful in the classification of patients.. Almost 50% of lean young and middle-aged patients were ICA+ and/or anti-GAD+, suggesting a high prevalence of a slowly evolving form of type 1 diabetes. The evaluation at diagnosis of both beta-cell secretory capacity and markers of autoimmunity is recommended to provide a pathogenetic classification of the disease. Topics: Adult; Autoantibodies; Blood Glucose; Body Mass Index; C-Peptide; Cohort Studies; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genotype; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DQ beta-Chains; Humans; Incidence; Islets of Langerhans; Italy; Male; Middle Aged; Thinness | 1999 |
Long-term survival and function of intrahepatic islet allografts in rhesus monkeys treated with humanized anti-CD154.
Reported effects of anti-CD154 treatment on autoimmunity, alloreactivity, and inflammatory events mediated by macrophages and endothelial cells indicated that it might be an ideal agent for the prevention of intrahepatic islet allograft failure. This hypothesis was tested in MHC-mismatched rhesus monkeys. Transplantation of an adequate number of viable islets resulted in engraftment and insulin independence in six of six recipients treated with anti-CD154 (hu5c8) induction plus monthly maintenance therapy (post-operative day >125, >246, >266, >405, >419, >476). Anti-CD154 (hu5c8) displayed no inhibitory effect on islet cell function. For monkeys followed for >100 days, continued improvement in graft function, as determined by first phase insulin release in response to intravenous glucose, was observed after the first 100 days post-transplant. No evidence of toxicity or infectious complications has been observed. All recipients treated with anti-CD154 became specifically nonresponsive to donor cells in mixed lymphocyte reactions. Furthermore, three monkeys are now off therapy (>113, >67, and >54 days off anti-CD154), with continued insulin independence and donor-specific mixed lymphocyte reaction hyporeactivity. In striking contrast to all previously tested strategies, transplantation of an adequate number of functional islets under the cover of anti-CD154 (hu5c8) monotherapy consistently allows for allogeneic islet engraftment and long-term insulin independence in this highly relevant preclinical model. Topics: Animals; Antibodies; Blood Glucose; C-Peptide; CD40 Ligand; Diabetes Mellitus, Type 1; Graft Survival; Humans; Immunosuppression Therapy; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Liver; Macaca mulatta; Membrane Glycoproteins; Pancreatectomy; Transplantation, Heterotopic; Transplantation, Homologous | 1999 |
Lack of acute zinc effects in glucose metabolism in healthy and insulin-dependent diabetes mellitus patients.
Acute or chronic zinc administration may cause hyperglycemia in experimental animals. These findings are attributed to permissive actions of glucocorticoids and glucagon upon hepatic gluconeogenesis and glycogenolysis. The effect of Zn(+)+ on plasma glucose, C-peptide, glucagon, and cortisol was investigated in healthy and insulin-dependent diabetes mellitus (IDDM) patients. Ten normal individuals (5 of each sex, aged 24.10 +/- 1.96) and 10 IDDM (5 of each sex, aged 25.20 +/- 8.10) were tested at 7:00 AM after 12-h fast. Twenty-five mg of Zn(+)+ were administered intravenously during 1 min, and blood samples were collected from the contralateral arm at 0, 3, 30, 60, 90 and 120 min after Zn(+)+ injection. The plasma levels of glucose, C-peptide, and glucagon remained constant throughout the experimental period in both groups studied. Plasma cortisol levels decreased significantly, which is consistent with our previous findings. These results suggest that, in contrast to experimental animals, acute Zn(+)+ administration, despite decreasing cortisol levels, does not change carbohydrate metabolism in human beings. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose; Humans; Hydrocortisone; Male; Zinc | 1999 |
Plasma endothelin-1 and total insulin exposure in diabetes mellitus.
Insulin stimulates endothelin-1 (ET-1) expression in a dose-response relationship, and ET-1 effects on vascular wall structure are similar to the long-term complications of diabetes. We therefore determined whether the plasma ET-1 concentration in patients with diabetes is associated with their total insulin exposure to see if plasma ET-1 might be a link between insulin exposure and long-term complications of diabetes. We studied 69 patients with Type I and 40 patients with Type II diabetes mellitus in equally tight glycaemic control for 2 years in a cross-sectional design. We measured basal and glucagon-stimulated plasma C-peptide, abdominal sagittal diameter, skinfold thickness, glomerular filtration rate, albumin excretion rate and standard clinical characteristics. Mean HbA1c was 6.4% in Type I and 6.3% in Type II diabetes. Patients with an albumin excretion rate >300 microg/min were excluded. Adjusted mean plasma ET-1 was 4.11 (S.E.M. 0.39) pg/ml in 21 normal subjects, 3.47 (0.19) pg/ml in Type I diabetes and 4.84 (0.26) pg/ml in Type II diabetes (P=0.0001). In all patients with measurable plasma C-peptide, plasma ET-1 was associated with basal plasma C-peptide (r=0.5018, P<0.0001), with stimulated plasma C-peptide (r=0.5379, P<0.0001), and with total daily insulin dose (r=0.2219, P=0.00851). Abdominal obesity, metabolic abnormalities, blood pressure and glomerular filtration rate were not associated with plasma ET-1, when corrected for C-peptide and daily insulin dose. Our study shows that the plasma concentration of ET-1 is closely associated with insulin secretion and insulin dose in patients with diabetes. Plasma ET-1 is higher in Type II diabetes than in Type I diabetes. Increased insulin exposure in patients with diabetes may have long-term effects on vascular wall structure through its stimulation of ET-1 expression. Topics: Adult; Aged; Aged, 80 and over; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Drug Administration Schedule; Endothelin-1; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Multivariate Analysis | 1999 |
Insulin resistance in HIV protease inhibitor-associated diabetes.
Fasting hyperglycemia has been associated with HIV protease inhibitor (PI) therapy.. To determine whether absolute insulin deficiency or insulin resistance with relative insulin deficiency and an elevated body mass index (BMI) contribute to HIV PI-associated diabetes.. Cross-sectional evaluation.. 8 healthy seronegative men, 10 nondiabetic HIV-positive patients naive to PI, 15 nondiabetic HIV-positive patients receiving PI (BMI = 26 kg/m2), 6 nondiabetic HIV-positive patients receiving PI (BMI = 31 kg/m2), and 8 HIV-positive patients with diabetes receiving PI (BMI = 34 kg/m2). All patients on PI received indinavir.. Fasting concentrations of glucoregulatory hormones. Direct effects of indinavir (20 microM) on rat pancreatic beta-cell function in vitro.. In hyperglycemic HIV-positive subjects, circulating concentrations of insulin, C-peptide, proinsulin, glucagon, and the proinsulin/insulin ratio were increased when compared with those of the other 4 groups (p < .05). Morning fasting serum cortisol concentrations were not different among the 5 groups. Glutamic acid decarboxylase (GAD) antibody titers were uncommon in all groups. High BMI was not always associated with diabetes. In vitro, indinavir did not inhibit proinsulin to insulin conversion or impair glucose-induced secretion of insulin and C-peptide from rat beta-cells.. The pathogenesis of HIV PI-associated diabetes involves peripheral insulin resistance with insulin deficiency relative to hyperglucagonemia and a high BMI. Pancreatic beta-cell function was not impaired by indinavir. HIV PI-associated diabetes mirrors that of non-insulin-dependent diabetes mellitus and impaired insulin action in the periphery. Topics: Adult; Animals; Anti-HIV Agents; C-Peptide; Cells, Cultured; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Glucagon; HIV Infections; HIV Protease Inhibitors; Humans; Indinavir; Insulin; Insulin Resistance; Islets of Langerhans; Male; Phospholipases A; Proinsulin; Rats; Rats, Sprague-Dawley | 1999 |
Clinical characteristics, and time course of pancreatic beta-cell function and glutamic acid decarboxylase antibodies in Thai patients with adult-onset Type 1 diabetes: distinction between patients of rapid- and slow-onset.
In order to study the clinical characteristics, time course of beta cell function and glutamic acid decarboxylase antibodies (GAD65Ab) in Thai patients with adult-onset Type 1 diabetes and to examine the distinctive features between patients with rapid-and slow-onset, 61 Thai patients with Type 1 diabetes who had age of disease onset at or after 20 years were studied. All patients were treated with insulin at the time of study and had fasting C-peptide levels +/-0.33 nmol/l. Twenty-six (42.6%) were in rapid-onset and 35 (57.4%) were in slow-onset groups. Fourty-four of 61 (70.5%) were male. About three-fourths had body mass index (BMI) < 19 kg/m2 at the time of insulin therapy. Only 7 of 61 (11.5%) patients had ketoacidosis at first presentation. Five patients had associated autoimmune thyroid disease and 10 (16.7%) patients had family history of diabetes in first-degree relatives. GAD65Ab was positive in 31 patients (50.8%); 10 (38.5%) were in rapid-onset and 21 (60.0%) were in slow-onset groups. GAD65Ab particularly of high levels were persistently elevated during 3-4 years follow-up period. The persistence of GAD65Ab were not associated with changes in fasting C-peptide levels. At the time of insulin dependency, there were no distinctive clinical features between rapid- and slow-onset patients except higher fasting C-peptide (0.08+/-0.08 vs. 0.14+/-0.10 nmol/l; p = 0.023) and GAD65Ab levels (19.6+/-17.4 vs. 46.1+/-49.7 U/ml; p = 0.036) in slow-onset patients. Fasting C-peptide levels of patients in the latter group were also demonstrated to be higher after 3-4 years of follow-up. In conclusion, most Thai patients with adult-onset Type 1 diabetes in this study were male and had significant degree of weight loss and lean BMI prior to insulin therapy. The presence of GAD65Ab did not predict clinical features or rate of beta cell loss. Patients in rapid-onset group had lower fasting C-peptide and GAD65Ab levels than those of slow-onset group which confirms the slower process of beta cell failure in the latter. Topics: Adult; Aged; Autoantibodies; Autoimmune Diseases; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glutamate Decarboxylase; Humans; Insulin; Islets of Langerhans; Male; Middle Aged; Thailand; Thyroid Diseases; Time Factors | 1999 |
Inverse distribution of serum sodium and potassium in uncontrolled inpatients with diabetes mellitus.
It has been reported that there is an inverse relationship between serum sodium (Na) and potassium (K) levels in patients with diabetic coma. The present study was undertaken to determine whether such an inverse relation depends upon plasma glucose levels in diabetic patients for their glycemic control. We examined two hundred and fifty-two patients with diabetes mellitus admitted to our hospital during the one-year period to control their plasma glucose levels, except for those having nephropathy or liver dysfunction. Serum Na and K, plasma glucose, and serum and urinary C-peptide levels were determined. There was a negative correlation between serum Na levels and fasting plasma glucose (FPG), and, conversely, a positive correlation between serum K levels and FPG. The changes were more evident in the patients with insulin-dependent diabetes mellitus than those with non-insulin-dependent diabetes mellitus. There was an inverse relation between serum Na and K levels and it was profoundly dependent upon plasma glucose levels in all the diabetic patients before tight control of their glycemic levels. The disorder may be based on the movement of electrolytes between intra- and extracellular spaces, dependent on the impaired insulin action as well as hyperosmolality. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Humans; Male; Middle Aged; Potassium; Sodium | 1999 |
Induction, maintenance, and reversal of streptozotocin-induced insulin-dependent diabetes mellitus in the juvenile cynomolgus monkey (Macaca fascilularis).
Insulin-dependent diabetes mellitus (IDDM) is the second most prevalent chronic illness of children. Investigation of the treatment of IDDM is hindered by the lack of a reproducible and easily maintained non-human primate model of this disorder.. We induced IDDM in 11 juvenile cynomolgus monkeys after a single (150 mg/kg) intravenous injection of streptozotocin (STZ). All diabetic monkeys were treated with insulin twice daily, based on a sliding scale. Subcutaneous vascular access ports were surgically placed in each monkey to facilitate serial blood sampling and drug administration. Allogeneic pancreatic islet cells from unrelated donors were subsequently transplanted into the mesenteric circulation of all STZ-treated monkeys.. Mild, transient nausea and vomiting occurred in all animals after STZ injection; however, no additional signs of toxicity occurred. Within 36 hr, all monkeys required twice daily administration of exogenous insulin to maintain a non-ketotic state. Serum C-peptide levels decreased from >1.2 ng/ml before STZ, to between 0.0 and 0.9 ng/ml after STZ, confirming islet cell destruction. Animals were maintained in an insulin-dependent state for up to 147 days without any observable clinical complications. Subcutaneous vascular access port patency was maintained up to 136 days with a single incidence of local infection. Islet cell transplantation resulted in normoglycemia within 24 hr. Serum C-peptide levels increased (range: 2-8 ng/ml) for 6 - 8 days in immune competent animals, and for 39-98 days after transplant in immunosuppressed monkeys.. IDDM can be consistently induced and safely treated in juvenile cynomolgus monkeys. Chronic vascular access can be maintained with minimal supervision and complications. This model is appropriate for studies investigating potential treatments for IDDM including islet cell transplantation. Topics: Animals; C-Peptide; Catheterization; Child, Preschool; Chronic Disease; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Femoral Vein; Glucose Tolerance Test; Humans; Immunosuppressive Agents; Insulin; Insulin Infusion Systems; Islets of Langerhans Transplantation; Kidney; Macaca fascicularis; Pancreas; Streptozocin; Vascular Patency | 1999 |
Leptin concentrations in cord blood in normal newborn infants and offspring of diabetic mothers.
Leptin has been implicated in the regulation of body weight and energy balance; Leptin is produced by adipocytes and placental tissue. Chronic fetal hyperinsulinemia and accelerated fetal growth with increased amounts of body fat are frequent findings in the offspring of diabetic mothers. In this study, we examined whether leptin levels in cord blood of infants of type 1 diabetic mothers (n = 29), gestational diabetic mothers (n = 6 and controls (n = 96) correlated with level of maternal glucose control, maternal leptin level at delivery, gender, fetal and placental size, and C-peptide in cord blood at birth. Leptin was significantly elevated in infants of type 1 diabetic (24.7 ng/ml) and gestational diabetic mothers (29.3 ng/ml) as compared to controls (7.9 ng/ml). C-peptide was also significantly higher in infants of type 1 diabetic (0.91 nmol/l) and gestational diabetic mothers (0.99 nmol/l) vs controls (0.34 nmol/l). Infants of type 1 diabetic mothers with a leptin level in cord blood above the upper normal range, i.e. > 30 ng/ml (n = 13), had an average maternal HbA1c level of 5.4% (normal < 5.5%) that was not different from 5.2% in infants with a leptin level < 30 ng/ml (n = 15). In both neonatal groups of diabetic mothers, leptin in cord blood did not correlate with maternal leptin concentrations, placental weight, birthweight, gender and cord blood C-peptide. In controls, leptin in cord blood was higher in girls than in boys (p = 0.044) and correlated significantly with birthweight (p = 0.41, p < 0.001) and cord blood C-peptide (p = 0.44, p < 0.001) but not with maternal leptin level or placental weight. The 3-4 times higher leptin levels in the offspring of diabetic mothers than normal could reflect increased adipose tissue mass and/or increased contribution from other sources such as placental tissue. Topics: Birth Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Fetal Blood; Gestational Age; Humans; Infant, Newborn; Leptin; Male; Organ Size; Placenta; Pregnancy; Pregnancy in Diabetics; Proteins; Sex Characteristics | 1999 |
Cellular immune response to GAD in type 1 diabetes with residual beta-cell function.
Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glutamate Decarboxylase; Humans; Immunity, Cellular; Insulin; Insulin Secretion; Islets of Langerhans; Lymphocyte Activation; T-Lymphocytes | 1999 |
Clinical, autoimmune, and genetic characteristics of very young children with type 1 diabetes. Childhood Diabetes in Finland (DiMe) Study Group.
To study the characteristics of type 1 diabetes in very young children.. Clinical outcome, islet cell antibodies (ICA), insulin autoantibodies (IAA), antibodies against GAD (GADA), IA-2 antibodies (IA-2A), and HLA-DQB1-defined genetic risk were analyzed in 35 children diagnosed with type 1 diabetes before 2 years of age and compared with those in 146 children who were diagnosed between 2.0 and 4.9 years of age and with those in 620 children diagnosed between 5.0 and 14.9 years of age.. The youngest age-group had severer metabolic decompensation at clinical onset, and their serum C-peptide levels, compared with those of older children, were lower at the time of diagnosis and during the first 2 years after the diagnosis. The levels of ICA and IAA were highest in children < 2 years of age, but there were no differences in GADA levels among the three age-groups. The youngest age-group had the lowest IA-2A levels. The HLA DQB1*02/*0302 genotype associated with strong genetic susceptibility was more frequent in children diagnosed < 5 years of age, whereas the proportion of children carrying a genotype, which includes protective alleles, was higher among those diagnosed at > or = 5 years of age.. The clinical presentation of type 1 diabetes at a very young age is associated with severe metabolic decompensation, poorly preserved residual beta-cell function, strong humoral autoimmunity against islet cells and insulin, and strong HLA-defined disease susceptibility. Topics: Adolescent; Age Factors; Alleles; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Genotype; Glutamate Decarboxylase; HLA-DQ Antigens; HLA-DQ beta-Chains; Humans; Insulin; Islets of Langerhans | 1999 |
Long-term metabolic control and pancreatic graft survival according to surgical technique.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Graft Survival; Humans; Insulin; Insulin Secretion; Male; Middle Aged; Pancreas Transplantation; Retrospective Studies; Time Factors; Treatment Failure | 1999 |
Metabolic and hormonal responses to exercise in type 1 diabetic patients during continuous subcutaneous, as compared to continuous intraperitoneal, insulin infusion.
This study was performed to determine whether metabolic and hormonal responses during moderate exercise differ between continuous intraperitoneal insulin infusion (CIPII) and continuous subcutaneous insulin infusion (CSII). In seven Type 1 diabetic patients, treatment was changed from CSII to CIPII. Prior to the change, these patients performed an ergometer exercise at 60% of VO2max for 40 min followed by a 200-min rest. About one year later, when the procedure was repeated during CIPII, HbA1c had improved from 8.5 to 7.1%. Arterial blood glucose, venous lactate and hormonal responses were analysed. Although a regimen with a higher basal insulin infusion rate was applied during the exercise test on CIPII, corresponding venous insulin levels were lower (28.0 +/- 2.2 vs. 48.1 +/- 7.9 pmol L-1, p = 0.04). Exercise caused a more marked decline in blood glucose during CIPII, with nadir blood glucose at the end of exercise (3.6 +/- 0.4 vs. 5.1 +/- 0.4 mmol L-1, p = 0.005). Both exercise tests yielded significant and similar increases in plasma levels of adrenaline, noradrenaline, cortisol and growth hormone. A significant rise in plasma glucagon (15.1 +/- 4.5 pg mL-1, p = 0.01) was observed during CIPII, but not during CSII (7.4 +/- 3.5, pg mL-1, n.s.). It is concluded that patients on CIPII should reduce their insulin infusion rate during exercise. CIPII appears to have favourable effects on counterregulatory capacity; in particular, a more prominent glucagon response to exercise may prove important. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Equipment Design; Exercise; Female; Glucagon; Glycated Hemoglobin; Human Growth Hormone; Humans; Hydrocortisone; Insulin Infusion Systems; Male; Middle Aged; Norepinephrine; Pulse | 1999 |
Higher post-absorptive C-peptide levels in Type 1 diabetic patients without renal complications.
Topics: Albuminuria; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Food; Humans | 1999 |
[Prevalence of diabetic retinopathy at the Dakar University Hospital Center].
The aim of the study is to appreciate the prevalence of diabetic retinopathy among senegalese patients in analyzing age of diagnosis, duration of diabetes, plasma glucose and type of retinopathy. 129 diabetics followed and treated in the diabetic center of internal medicine clinic (Dakar University) were examined by 90 degrees Volk's lens. A determination of plasma c peptide and glucose concentration were performed. 55 (mean age 224. +/- 0.9 years) were insulino-dependent and 74 (mean age of 54.7 +/- 11.4 years) non insulinodependent. On average the duration of diabetes was 5.4 years +/- 5.4 for the former and 6.07 +/- 5.7 for the latter with respectively glucose plasma average 2.60 g/l +/- 0.7 and 1.7 g/l +/- 0.83. Retinopathy was found in 29 patients. So total prevalence was 22.48%, shared in 29.7% for non insulino-dependant and 12.7% for insulino-dependent. In 7 cases the retinopathy was proliferative and non proliferative in 22 cases essentially among non insulino-dependant diabetics. The diabetic retinopathy is one of handicaping complications of diabetics. Its prevalence is strongly linked to the duration of diabetes, glycaemic control and to other risk factors (genetics, glycosylated hemoglobin and high blood pressure). Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Glycated Hemoglobin; Hospitals, University; Humans; Male; Middle Aged; Prevalence; Senegal | 1999 |
Renal functional reserve in IDDM patients.
The aim of this study was to determine whether renal functional reserve (RFR) is altered in insulin-dependent diabetic (IDDM) patients according to the stage of diabetic nephropathy. RFR was examined in 33 IDDM patients in similar glycaemic and metabolic control and compared to 12 healthy control subjects, during eight 1 h clearance periods prior to, during and after a 3-h stimulation by amino acid infusion (4.5 mg x kg(-1) x min[-1]). RFR was calculated as the difference between stimulated and baseline glomerular filtration rates (GFR). In 14 early normotensive diabetic patients with normal urinary albumin excretion, mean baseline GFR (133 +/- 3 ml x min(-1) x 1.73 m[-2]) was higher whereas RFR (10 +/- 4 ml x min(-1) x 1.73 m[-2]) was lower (p < 0.05) than in control subjects (113 +/- 4 and 28 +/- 2 ml x min(-1) x 1.73 m(-2), respectively). In 10 normotensive patients who had lived with IDDM for 16 years and who had microalbuminuria, baseline GFR and RFR (109 +/- 7 and 24 +/- 6 ml x min(-1) x 1.73 m(-2), respectively) were similar to those in control subjects. In 9 patients who had suffered IDDM for 23 years and had developed macroalbuminuria and hypertension, baseline GFR (78 +/- 8 ml x min(-1) x 1.73 m[-2]) was lower than in control subjects (p < 0.05) and RFR (8 +/- 4 ml x min(-1) x 1.73 m[-2]) was not significant. In addition, renal vascular resistance decreased significantly during infusion (p < 0.05) in microalbuminuric normotensive patients as well as in control subjects (by 9 +/- 4 and 11 +/- 4 mmHg x l(-1) x min(-1) x 1.73 m(-2), respectively) but not in normoalbuminuric normotensive or macroalbuminuric hypertensive patients. These results indicate that microalbuminuric normotensive patients retain a normal RFR, whereas RFR is reduced or suppressed at two opposite stages of the disease: in normoalbuminuric normotensive patients with a high GFR and in macroalbuminuric hypertensive patients with a decreased GFR. This dissimilar impairment reveals permanent glomerular hyperfiltration in both early IDDM without nephropathy and IDDM with overt diabetic nephropathy, but not in IDDM with incipient nephropathy. Topics: Adult; Albuminuria; Aldosterone; Amino Acids; Blood Glucose; Blood Pressure; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Dietary Proteins; Female; Glomerular Filtration Rate; Glycated Hemoglobin; Humans; Hypertension; Kidney; Male; Reference Values; Renal Circulation; Renin; Vascular Resistance | 1998 |
Ernst-Friedrich-Pfeiffer Memorial Lecture. New aspects of C-peptide physiology.
C-peptide is co-secreted with insulin and has generally been considered not to possess biological activity. However, several recent studies during the last five years have demonstrated that administration of C-peptide in physiological amounts to type 1 diabetes (IDDM) patients on a short term basis (1-3h) results in decreased glomerular hyperfiltration, augmented glucose utilization and improved autonomic nerve function. More prolonged administration (1-3 months) of C-peptide to IDDM patients is accompanied by improvements in both renal function (diminished microalbuminuria) and autonomic and sensory nerve function. Both in vitro and in vivo data indicate that C-peptide may have a role in the regulation of insulin secretion. C-peptide's mechanism of action is not known but it may be related to its ability to stimulate Na+, K(+)-ATPase, activity, probably by activating a receptor coupled to a pertussis toxin-sensitive G-protein with subsequent activation of Ca2(+)-dependent intracellular signaling pathways. In conclusion, the combined findings indicate that C-peptide is a biologically active hormone. The possibility that C-peptide therapy in IDDM patients may be beneficial should be considered. Topics: Albuminuria; Amino Acid Sequence; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Enzyme Activation; Heart Rate; Insulin; Insulin Secretion; Kidney; Molecular Sequence Data; Peptide Fragments; Sodium-Potassium-Exchanging ATPase | 1998 |
Antibodies to pancreatic islet cell antigens in diabetes seen in Southern India with particular reference to fibrocalculous pancreatic diabetes.
Fibrocalculous pancreatic diabetes (FCPD) is a type of diabetes secondary to tropical chronic non-alcoholic pancreatitis. Little is known about the aetiopathogenesis of FCPD. We studied glutamic acid decarboxylase antibodies (GAD-Ab) and islet cell antibodies (ICA) in patients with FCPD and compared the results with Type 1 (insulin dependent) diabetes mellitus, Type 2 (non-insulin-dependent) diabetes mellitus and non-diabetic subjects in Southern India. The prevalence of GAD-Ab was 7.0% (95% Confidence Interval (CI) 1.9-17.2) in FCPD, 47.5% (CI 31.4-64.0) in Type 1 (p < 0.001 compared to FCPD), 5.6% (CI 1.5-13.9) in Type 2 (non-significant (NS) compared to FCPD) and 0% in controls. The prevalence of ICA was 6.3% (CI 1.2-17.4) in FCPD, 53.8% (CI 37.1-70.0) in Type 1 (p < 0.001 compared to FCPD), 9.9% (CI 4.0-19.4) in Type 2 (NS compared to FCPD) and 4.7% (CI 0.4-16.1) in controls. The data suggest that in FCPD, the frequency of auto-antibodies is low and its aetiology is probably not linked to autoimmunity in the majority of the patients. Topics: Adult; Autoantigens; C-Peptide; Chronic Disease; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; India; Islets of Langerhans; Male; Middle Aged; Pancreatic Diseases; Pancreatitis; Reference Values | 1998 |
Gender, autoantibodies, and obesity in newly diagnosed diabetic patients aged 40-75 years.
To evaluate the frequency of autoimmune markers (islet cell antibodies (ICA] and glutamic acid decarboxylase antibodies [GADA]) and clinical features in newly diagnosed people with diabetes aged 40-75 years.. Two hundred fifty-nine consecutive patients (aged 40-75 years) with newly suspected diabetes diagnosed during a 2-year period were studied. The diagnosis of newly discovered diabetes was confirmed in 203 patients. Gender, BMI, HbA1c, fasting C-peptide, ICA, and GADA were evaluated. The frequency of obesity was estimated using two different sets of criteria: 1) National Diabetes Data Group (NDDG) criteria, and 2) criteria based on a Swedish reference population.. The annual incidence of diabetes was 106 per 100,000 people. The incidence of diabetes in those patients who were 40-54 years old was significantly higher in men than in women (odds ratio: 2.16; P = 0.001). ICA were detected in 16 of 203 patients (8%), whereas 17 of 203 patients (8%) were GADA+; 10 of 203 (5%) patients were positive for both ICA and GADA. Among the 203 diabetic patients, 19 (9.4%) were classified as having IDDM, giving an IDDM incidence of 10 per 100,000 people aged 40-75 years. The frequency of obesity in NIDDM was high but varied with its definition; the frequency of obesity was highest (P < 0.001) when NDDG criteria, and not Swedish reference values, were used (57 of 75 [76%] vs. 40 of 75 [53%] for women and 66 of 109 [61%] vs. 45 of 109 [41%] for men).. A striking male preponderance was found among incident cases of diabetes in people aged 40-54 years. Autoimmune markers were detected in 10% of incident cases of diabetes in people aged 40-75 years. Using a conservative estimation, as many as 10 of 100,000 middle-aged and elderly subjects developed IDDM. The frequency of obesity in NIDDM was high but this was also the case in the reference population. Topics: Adult; Aged; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Middle Aged; Obesity; Sex Factors; Sweden | 1998 |
Pubertal growth in IDDM is determined by HbA1c levels, sex, and bone age.
In cross-sectional studies of subjects with IDDM, the relationship between suboptimal pubertal growth, glycemic control, and abnormal insulin-like growth factor I (IGF-I) levels has proved difficult to define. The objective of this study was to examine these relationships in a longitudinal prospective study.. A total of 46 children (23 boys) were measured every 3 months, and their bone age was assessed annually. Blood samples were obtained for HbA1c, IGF-I, and C-peptide. Growth data were compared with national standards, and IGF-I data were compared with a parallel longitudinal study of normal schoolchildren. Data were analyzed as SD scores (mean +/- SD).. The onset of puberty was not delayed, although in the girls, bone age was advanced (bone age, 11.48 +/- 1.01 years vs. chronological age, 10.93 +/- 0.86 years [mean +/- SD]; P = 0.04). The timing of peak height velocity (PHV) was normal in both sexes, but the magnitude was reduced in girls (PHV SDS = -0.56 +/- 0.90, P < 0.02), and reductions in height SDS between diagnosis and final height were observed (P = 0.014). At PHV, IGF-I levels were reduced in both sexes, and there were no sex differences in HbA1c levels and insulin doses. IGF-I SDS correlated with insulin dose (r = 0.47, P = 0.004) but not with PHV SDS, whereas HbA1c correlated negatively with PHV SDS in both sexes (r = -0.35, P = 0.03). In a stepwise multiple regression analysis, the major determinants of PHV SDS were HbA1c (P = 0.04), sex (P = 0.0007), and bone age (P = 0.01).. We conclude that the magnitude of the pubertal growth spurt is related to HbA1c levels in both sexes, but it is reduced only in girls. This sexual dimorphism cannot be explained by differences in IGF-I levels and may relate to the bone age advance at the onset of puberty in the girls. Topics: Body Height; Bone and Bones; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Growth; Humans; Hypoglycemic Agents; Insulin; Insulin-Like Growth Factor I; Male; Menarche; Puberty; Regression Analysis; Sex Factors | 1998 |
Autoimmune and clinical characteristics of type I diabetes in children with different genetic risk loads defined by HLA-DQB1 alleles. Childhood Diabetes in Finland Study Group.
1. The impact of different genetic risk loads defined by HLA-DQB1 alleles on the autoimmune and clinical characteristics of 647 children and adolescents with recent-onset Type I diabetes was evaluated in a prospective population-based study. The subjects were divided into four groups based on HLA-DQB1 genotypes: DQB1*0302/0201 (high risk), *0302/x (moderate risk), *0201/y (low risk) and *z/z (decreased risk). 2. Close to two thirds (62.3%) of the subjects possessed a high or moderate risk genotype. A decreased frequency of positivity for islet cell antibodies (ICA) and insulin autoantibodies (IAA) (76.8% compared with 85.3%; P = 0.05, and 30.5% compared with 50.8%, P = 0.0006, respectively) but not of positivity for antibodies to the 65 kDa isoform of glutamate decarboxylase was observed in children with the DQB1*0201/y genotype compared with other children. Among ICA-negative subjects, those with the DQB1*0201/y genotype had higher serum C-peptide levels over the first 2 years after the diagnosis of Type I diabetes than those with other genotypes (P = 0.028). 3. Our data provide some evidence of HLA-DQB1-determined heterogeneity in the autoimmune and clinical characteristics of childhood Type I diabetes at the time of the clinical manifestation. This suggests differences between children with various HLA-DQB1 genotypes in the pace and/or intensity of the beta-cell destructive process leading to clinical Type I diabetes. Topics: Adolescent; Alleles; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Susceptibility; Female; Follow-Up Studies; Genotype; Glutamate Decarboxylase; HLA-DQ Antigens; HLA-DQ beta-Chains; Humans; Infant; Infant, Newborn; Insulin Antibodies; Islets of Langerhans; Male; Prospective Studies | 1998 |
A new point mutation (3426, A to G) in mitochondrial NADH dehydrogenase gene in Korean diabetic patients which mimics 3243 mutation by restriction fragment length polymorphism pattern.
Mitochondrial tRNA(Leu)(UUR) gene mutation is one of the candidates in the pathogenesis of NIDDM. Especially the 3243 (A-->G) mutation is associated with the maternally-inherited diabetes and deafness. To evaluate the prevalence and characteristics of the 3243 point mutation in Koreans, we screened 433 Korean diabetic patients (220 men and 213 women). Genomic DNA was extracted from peripheral white blood cells and PCR was carried out with mitochondrial DNA primers (3130-3149, 3558-3539) encompassing the 3243 position. After digestion with Apa-1, five subjects showed polymorphism suggesting 3243 point mutation but when we directly sequenced the amplified DNA with an automatic sequencer, only 2 of the 5 patients were shown to have 3243 (A-->G) mutation and the other 3 subjects had 3426 (A-->G) mutation rather than 3243 mutation. Two diabetic patients with 3243 mutation were lean (BMI = 14.4, 17.0 kg/m2), had relatively lower fasting C-peptide concentrations (0.9 ng/ml each), and required insulin for management. In contrast, those with 3426 point mutation were not lean (BMI = 22.6-28.0 kg/m2), had relatively higher C-peptide levels (3.9-5.4 ng/ml), and could be managed with oral hypoglycemic agents. None of the 5 patients had deafness. In conclusion, the prevalence of 3243 point mutation in Korean diabetic patients was approximately 0.5% and we found a new mutation mimicking 3243 mutation by PCR-RFLP (restriction fragment length polymorphism) pattern. We suggest that sequencing of the PCR product or designing smaller PCR fragment size to enhance the specificity may help to identify the exact location of the point mutation. Topics: Adult; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; DNA, Mitochondrial; Female; Humans; Korea; Male; Middle Aged; NADH Dehydrogenase; Point Mutation; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length | 1998 |
Identification of a single nucleotide insertion polymorphism in the upstream region of the insulin promoter factor-1 gene: an association study with diabetes mellitus.
Insulin promoter factor 1 (IPF1) is a key factor both for the regulation of insulin gene expression and for the development of the pancreas. In this study 88 patients with non-insulin-dependent diabetes mellitus (NIDDM) who were diagnosed as diabetic at less than 40 years of age, 55 patients with insulin-dependent-diabetes (IDDM), and 67 normal control subjects were analysed for variants in the upstream region of the IPF1 gene by direct sequencing. A novel single nucleotide insertion polymorphism was found in a guanine triplet at 108 bp upstream of the translation start site. The G insertion allele (G4 allele) was found to be common in the Japanese population, at a frequency of 0.50. The prevalence of G3 homozygotes was higher in IDDM patients (35%) and lower in NIDDM patients (17%) than in normal control subjects (28%, p=0.049). In the NIDDM group, the ratio of insulin treatment tended to be higher in subjects homozygous for the G3 allele, although the genotype was not significantly associated with basal C-peptide levels. The polymorphism is unlikely to be a major contributor to the insulin deficiency of diabetes. However, the polymorphic locus, or an unknown mutation which is in linkage disequilibrium with the polymorphism, could be involved in the pathophysiology of diabetes. The high heterozygosity may be useful for genetic linkage studies of other mutations within and near the IPF1 gene. Topics: Adolescent; Adult; Alleles; Base Sequence; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; DNA Mutational Analysis; Female; Gene Frequency; Genes; Genotype; Guanine Nucleotides; Heterozygote; Homeodomain Proteins; Homozygote; Humans; Hypoglycemic Agents; Insulin; Male; Mutagenesis, Insertional; Polymorphism, Genetic; Trans-Activators | 1998 |
[Transplantation of islets of Langerhans in type 1 diabetes. Three cases treated in Sweden to date].
The article consists in a report of the first three cases of human islet transplantation to have been carried out in Sweden. Cadaveric pancreatic glands were harvested and flown to the islet transplantation laboratory at the University of Giessen in Germany. After isolation, the islets were returned to Huddinge Hospital in Stockholm. The recipients were diabetic renal transplant patients, who received 5,000-8,000 islets by intraportal injection. Initially blood glucose levels were stabilised and HbA1c levels normalised, but no patient became insulin independent. After a few months serum C-peptide levels diminished, and after 6-10 months were undetectable. Islet function loss is probably to be explained by rejection and cytomegalvirus infection. In future cases new improved immunosuppressive protocols will be implemented. Topics: Adult; C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Graft Rejection; Humans; Islets of Langerhans Transplantation; Male; Middle Aged; Prognosis | 1998 |
Clinical classification of diabetes in tropical west Africa.
The objective of this work was to classify and describe the different types of diabetic patients detected in West Africa. In four health centres (three in Ivory Coast, one in Niger) 310 new cases were detected and followed up over 1 year. Classification was based on age at diagnosis, BMI, ketonuria, basal and stimulated C-peptide levels at inclusion, and response to antidiabetic therapy. In this population, males were predominant (sex ratio = 2.40), and random blood glucose levels very high at screening (mean +/- SE, 18.6 +/- 0.4 mmol/l). Only one case of fibrocalculous pancreatic diabetes and one possible case of diabetes mellitus related to malnutrition were detected. IDDM was diagnosed in 11.3% of the patients, half of them above 35 years. Leanness was observed in 59% of the patients with NIDDM. A dramatic decrease of fasting blood glucose was observed in all groups after 2 months of treatment, especially in NIDDM. As IDDM and non-obese NIDDM presented great similarities before treatment, even for C-peptide levels, a point score system is proposed to classify these two groups at baseline. In conclusion, it is confirmed that the form of diabetes previously defined as related to malnutrition is a very rare entity in black African populations. In contrast, African diabetes is characterised by the high proportion of NIDDM patients with low BMI, and reduced beta-cell function, rarely associated to ketonuria. This form of diabetes seems to be adequately controlled with oral hypoglycaemic drugs and/or diet in the year following diagnosis. Topics: Adult; Africa, Western; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Ketone Bodies; Male; Middle Aged; Sex Factors | 1998 |
Effect of residual endogenous insulin secretion on the abnormal oxytocin response to hypoglycaemia in insulin-dependent diabetics.
Arginine-vasopressin (AVP) and oxytocin (OT) secretions are abnormally stimulated by hypoglycaemia in patients with IDDM. Since previous studies showed that AVP secretion is influenced by the persistence of residual endogenous insulin secretion, we wondered whether this factor also regulates OT secretion.. Case-control study: the OT response to insulin-induced hypoglycaemia was measured in normal and diabetic patients with or without residual endogenous insulin secretion.. Ten normal male subjects, 10 C-peptide positive (CpP) and 11 C-peptide negative (CpN) male diabetic patients.. plasma C-peptide levels were measured after intravenous administration of 1 mg glucagon. Insulin tolerance test (ITT): diabetics were studied after optimization of their metabolic status by 3 days of treatment with constant subcutaneous insulin infusion. CpP and CpN diabetics and normal controls were tested with an intravenous administration of 0.15 IU per kg body weight insulin. Blood samples for OT assay were taken just before the rapid injection of insulin (time 0) and at time 15, 30, 45 and 60 min.. The basal concentrations of OT were similar in all groups. Insulin induced a similar hypoglycaemic nadir in all groups at 30 min, even though diabetic groups showed a delayed recovery in blood glucose levels. The glycaemic pattern was similar in all diabetic patients. Hypoglycaemia-induced OT rise was significantly higher in the two diabetic groups than in the normal group. However, CpN patients showed significantly higher OT increments than CpP subjects.. These data indicate that a residual endogenous insulin secretion exerts a partial protective action against the hypothalamic-pituitary disorder affecting the OT secretory system in IDDM. Topics: Adult; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Glucagon; Humans; Hypoglycemia; Injections, Intravenous; Insulin; Insulin Secretion; Male; Oxytocin | 1998 |
Erythrocyte Na/K ATPase activity and diabetes: relationship with C-peptide level.
Erythrocyte Na/K ATPase activity is decreased in Type I diabetic patients; for Type II diabetic patients, literature data are controversial. Therefore, we have compared this enzymatic activity in 81 patients with Type I diabetes mellitus, 87 with Type II diabetes mellitus and 75 control subjects. Mean erythrocyte Na/K ATPase activity was lower in the Type I diabetic patients (285 +/- 8 nmol Pi x mg protein(-1) x h(-1)) than in the control subjects (395 +/- 9 nmol Pi x mg protein(-1) x h(-1)) whereas that of the Type II diabetic patients did not differ from that of control subjects. Sex, age, body mass index, and HbA1c levels did not influence erythrocyte Na/K ATPase activity. The 25 Type II diabetic patients treated with insulin, however, had lower Na/K ATPase activity than the 62 on oral treatment (264 +/- 18 vs 364 +/- 16 nmol Pi x mg protein(-1) x h(-1), p < 0.001) but similar to that of Type I diabetic patients. Among the Type II diabetic patients, stepwise regression analysis showed that fasting C-peptide level was the only factor independently correlated with Na/K ATPase activity; it explained 23% of its variance. In fact, in the insulin-treated patients, those with almost total endogenous insulin deficiency (C-peptide < 0.2 nmol x l(-1)) had the lower Na/K ATPase activity (181 +/- 21 vs 334 +/- 17 nmol Pi x mg protein(-1) x h(-1), p < 0.0001). The biological effects of treatment with C-peptide have recently led to the suggestion that this peptide could have a physiological role through the same signalling pathway as insulin, involving G-protein and calcium phosphatase and thus restoring Na/K ATPase activity. The relationship we describe between endogenous C-peptide and this activity is a strong argument for this physiological role. Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Erythrocytes; Fasting; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Regression Analysis; Sodium-Potassium-Exchanging ATPase | 1998 |
Interferon-alpha and development of type 1 diabetes: a case without insulin resistance.
Topics: Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glutamate Decarboxylase; Hepatitis C; Humans; Insulin; Interferon-alpha; Middle Aged | 1998 |
Metabolic and immune parameters at clinical onset of insulin-dependent diabetes: a population-based study. IMDIAB Study Group. Immunotherapy Diabetes.
The age at diagnosis of insulin-dependent diabetes mellitus (type I DM) varies between childhood and adulthood. The aim of this study was to define the immunologic and metabolic characteristics of the disease according to the age at which it is diagnosed. We evaluated the residual beta-cell function (basal and stimulated C-peptide) and frequency of two major islet cell-related autoantibodies, glutamic acid decarboxylase (GAD) and tyrosine phosphatase-like molecule (IA-2ic), at the onset of type I DM. A population-based study was performed with 235 consecutive cases of recent-onset (<4 weeks) type I DM (ages 5 to 45 years) diagnosed in the Lazio region of central Italy. Five age groups were considered: patients diagnosed between ages 5 and 7 years (n = 10), 7 and 10 years (n = 38), 10 and 17 years (n = 94), 17 and 20 years (n = 17), and 20 and 45 years (n = 76). Patients diagnosed before puberty had significantly reduced C-peptide secretion compared with patients diagnosed at a later age (P < .02). Glycosylated hemoglobin (HbA1c) did not differ at diagnosis between the different age groups. Patients diagnosed at puberty or after required significantly less insulin compared with younger patients (P < .04). GAD antibodies were found in 65% and IA-2ic antibodies in 59% of patients. GAD antibodies tended to be more frequent in patients diagnosed after age 17 compared with younger patients (P = .05), while IA-2ic antibodies were not age-related. These data suggest that (1) the extent of beta-cell damage differs between patients diagnosed before and after puberty, the process being more destructive in children less than 7 years of age, when C-peptide levels are the lowest; and (2) residual beta-cell function at diagnosis is not influenced by the presence or absence of islet cell-related antibodies. These findings have implications for trials in type I DM diagnosis aimed at protecting beta cells from end-stage destruction and in attempts to prevent the disease in susceptible individuals. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Humans; Male; Middle Aged; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases | 1998 |
Glucose homeostasis standards for pancreas transplantation.
Simultaneous pancreas and kidney transplantation (SPK) is capable of achieving normoglycemia, as assessed by oral glucose tolerance tests (OGTT), in the majority of diabetic recipients with end-stage renal disease. Despite its success over the last decade, standard ranges for OGTT after SPK are not available for comparison between studies and techniques. We examined 327 prospectively performed OGTT, undertaken in insulin-free bladder-drained SPK recipients, between 1 month and 10 yr after transplantation. Ranges of values for glucose, insulin and C-peptide were derived and areas under the time concentration curves calculated. The normal range of 2-h glucose values from SPK recipients was comparable to WHO criteria for the diagnosis of diabetes mellitus in a normal population; however, the fasting glucose fell below these levels. Fasting and area-under-the-curve (AUC) glucose were remarkably stable with time after SPK, although insulin fell with time after pancreas transplantation. These ranges may allow clinical evaluation of the endocrine function in individual SPK recipients, provide standards for comparison between different centers and techniques, and provide targets for islet transplantation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucose Tolerance Test; Homeostasis; Humans; Insulin; Kidney Transplantation; Male; Pancreas Transplantation; Prospective Studies | 1998 |
Effect of long-term treatment with a purified micronized flavonoid fraction on pancreatic mononuclear cell infiltration in diabetic BB rats.
Bio Breeding (BB) rats develop a genetically determined insulin-dependent diabetes, because of the early destruction of pancreatic beta cells of Langerhans islets, massively infiltrated by inflammatory mononuclear cells. S 5682, registered as Daflon, 500 mg, is a purified micronized flavonoid fraction (90% diosmin, 10% hesperidin), which has been shown to possess antiinflammatory properties, including anti-free radical activity, effects on vascular permeability, venous tone, and perivenous inflammation. We studied the effect of S 5682 on the course of pancreatic insulitis in diabetic BB rats. All the diabetic BB rats were hyperglycemic, with an increase of plasma levels of fructosamine, alpha-1 acid glycoprotein, and fibrinogen, and a dramatic decrease of C-peptide level. These parameters were not modified by S 5682. Pancreas histologic studies showed that in S 5682-treated diabetic BB rats, lymphocytic infiltration of Langerhans islets was less important and frequent than in untreated diabetic BB rats. By quantitative analysis, a highly significant difference was observed for insulitis, as well as perivasculitis, between S 5682-treated and untreated diabetic BB rats. This inhibitory effect of S 5682 on pancreatic mononuclear cell infiltration may be useful for a complementary treatment to decrease the development of insulitis in human insulin-dependent diabetes mellitus. Topics: Animals; C-Peptide; Chemotaxis, Leukocyte; Diabetes Mellitus, Type 1; Diosmin; Drug Combinations; Fibrinogen; Flavonoids; Fructosamine; Hesperidin; Islets of Langerhans; Leukocytes, Mononuclear; Male; Orosomucoid; Rats; Rats, Inbred BB | 1998 |
Plasma leptin levels in newborns from normal and diabetic mothers.
Leptin can be considered as a peripheral signal which informs the centers about the mass of energy stores. Studies done on the human adult population have demonstrated that degree of adiposity and insulin levels play a major role as determinants of leptin circulating levels. The aim of this study was to evaluate which factors may influence leptin levels at birth. We examined the role played by baby size and by the metabolic environment the fetus was exposed to during pregnancy. We considered 85 newborns from normal (n = 60), gestational (GDM, n = 17) and pregestational (IDDM = 8) diabetes mellitus mothers. At delivery, blood was taken from the umbilical cord vein. Babies from normal and GDM mothers were subdivided into AGA (appropriate for gestational age) and LGA (large for gestational age). There was no difference in leptin levels between babies from normal or GDM mothers belonging to the same weight category, but leptin levels were always higher in LGA than in AGA newborns, and highly correlated with birth weight (r = 0.34, P = 0.001). Moreover, IDDM mothers gave birth to newborns with significantly higher levels of leptin and insulin when compared with normal and GDM mothers. Diabetes of both GDM and IDDM mothers was clinically well controlled (HbA1c was 4.0 and 7.2, respectively). The correlation between leptin and insulin was significant only when newborns from IDDM mothers were included in the regression analysis (r = 0.39, P = 0.0002). Our results suggest that degree of adiposity is one of the main regulators of leptin concentration in the human newborn and that babies exposed to an altered, though clinically controlled, metabolic environment, as in IDDM mothers, have increased levels of leptin. Topics: Adipose Tissue; Adult; Birth Weight; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Glycated Hemoglobin; Humans; Infant, Newborn; Insulin; Insulin-Like Growth Factor Binding Protein 1; Insulin-Like Growth Factor I; Leptin; Multivariate Analysis; Pregnancy; Proteins; Regression Analysis; Testosterone | 1998 |
[Importance of short-term administration of low doses of somatostatin analog in the development and remission of type 1 diabetes mellitus in adult patients].
The objective of the presented work was to evaluate the short-term administration of octreotide on the development, onset and persistence of remission in recent insulin-dependent diabetics. The importance of remission means for the patient a clinically favourable condition with satisfactory metabolic compensation and a greater metabolic stability during the subsequent course of the disease. The period of remission is important from the aspect of prevention of late organ complications. Two-week treatment with octreotide, 150 micrograms/day, administered during the first month after establishment of the diagnosis was not associated with serious undesirable effects. Treatment with octreotide led to more frequent development of remission, partial and complete, as compared with a control group. In the majority of diabetics in the intervened group remission started immediately after administration of octreotide. The serum value of peptide-C as part of the glucagon test made at the time of diagnosis had a predictive value for the development of induced and spontaneous remission. Octreotide administration increased the probable development of remission even in patients with a substantially lower peptide C value at the time of diagnosis as compared with controls. The preliminary results indicate also a protraction of the remission period. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Male; Octreotide; Remission Induction | 1998 |
Association of endogenous insulin secretion and mode of therapy with body fat and serum leptin levels in diabetic subjects.
Insulin is one of the hormonal regulators of leptin synthesis and participates in adipose tissue maintenance. The present study was undertaken to clarify the association of endogenous insulin secretion and mode of therapy with body fat and serum leptin levels in diabetic subjects. We measured the fasting serum C-peptide level, as an estimate of endogenous insulin secretion, and the serum leptin level in 176 Japanese diabetic subjects (79 men and 97 women; age, 55.9+/-14.3 years; body mass index [BMI], 23.8+/-4.1 kg/m2 [mean+/-SD]). Thirty-one subjects were treated with diet therapy alone, 66 with sulfonylurea (SU), and 79 with insulin (including 29 with type I diabetes mellitus). Body fat was analyzed by the impedance method. Serum leptin levels significantly correlated with the BMI and body fat and were higher in women, mainly because of their greater body fat. Serum C-peptide concentrations positively correlated with body fat and serum leptin in subjects treated with diet and SU. In insulin-treated type II diabetic subjects, both serum C-peptide and the daily insulin dose were weakly associated with body fat and serum leptin. In those subjects, despite a lower percent body fat and body fat mass, serum leptin concentrations (10.3+/-8.4 ng/mL) were comparable to the levels in subjects treated with diet (8.8+/-8.5 ng/mL). When compared within the same BMI and body fat groups (BMI 20 to 25 and > 25 kg/m2) including the control subjects matched for age and sex, serum leptin levels were higher in insulin-treated type II diabetic subjects versus the control subjects and diabetic patients treated with diet or SU. Stepwise regression analysis for all of the diabetic subjects showed that both the serum C-peptide level and exogenous insulin administration, as well as the BMI, gender, and age, were determinants of the serum leptin level. In conclusion, endogenous insulin secretion is closely associated with body fat and serum leptin in diabetic subjects treated with diet therapy and SU. In Japanese insulin-treated type II diabetic subjects, both endogenous and exogenous insulin are associated with body fat and serum leptin, which is maintained at levels comparable to or somewhat higher than the levels in control subjects and diabetic patients treated without insulin. Topics: Adipose Tissue; Adult; Aged; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Ketones; Leptin; Lipids; Male; Middle Aged; Proteins | 1998 |
Insulin gene transfer can be a new optional therapy for replacement of pancreas.
Topics: Adenoviridae; Animals; Blood Glucose; C-Peptide; Cell Line; Diabetes Mellitus, Type 1; Dogs; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Humans; Hypoglycemic Agents; Insulin; Pancreatectomy; Proinsulin; Protein Precursors; Recombinant Proteins; Transfection | 1998 |
Antibodies to glutamic acid decarboxylase in young Chinese diabetic patients.
Antibodies to glutamic acid decarboxylase (GAD) are a useful autoimmune marker for type 1 diabetes mellitus in Caucasians. We examined antibodies to GAD and their relationships with clinical features and pancreatic beta cell function in 140 young Chinese diabetic patients. Over an 18-month period beginning in 1995, 140 young Chinese diabetic subjects with age of onset of disease < or = 35 years and age < 40 years were recruited consecutively, irrespective of their modes of presentation. Clinical features, antibodies to GAD and pancreatic beta cell function (using a glucagon stimulation test) were examined. Increased levels of antibodies to GAD (> 18 units) were detected in 12.1% (n = 17) of these subjects. Forty-three (31%) patients had a classical type 1 presentation and 65 (46%) patients were insulin-deficient based on post-glucagon plasma C-peptide levels. Patients who were insulin-deficient and had a type 1 presentation had the highest prevalence of antibodies to GAD (29.0%) compared with patients who had a type 2 presentation and were non-insulin deficient (6.4%, P = 0.003). Patients who had antibodies to GAD had lower body mass index and waist-hip ratio, earlier onset of disease, lower blood pressure, plasma triglyceride and C-peptide, and higher concentrations of plasma high-density lipoprotein cholesterol and glycated haemoglobin, and were more likely to require drug treatment, compared with those without antibodies to GAD. In conclusion, there was a low prevalence of antibodies to GAD in Chinese young diabetic patients although such antibodies remained a relatively specific marker for insulin deficiency and acute presentation. Causes other than autoimmunity should be sought to explain the high prevalence of insulin deficiency in these young Chinese patients. Topics: Antibodies; Asian People; C-Peptide; China; Diabetes Mellitus, Type 1; Glutamate Decarboxylase; Humans; Islets of Langerhans | 1998 |
[Insulin dependent (type 1) diabetes mellitus in advanced age].
In everyday praxis diabetes mellitus diagnosed over the age of fifty years, means generally type 2 diabetes. Authors present cases where diabetes, beginning in advanced age, showed typical classical diabetic symptoms, like polyuria, polydipsia, loss of bodyweight. Apart from these signs a rapid decompensation of carbohydrate metabolism characterises this diabetes form. The most significant features are the rapid decrease of serum immunoreactive insulin and C-peptide levels, what is characteristic for the diminishing insulin secretory capacity. The patients had to be switched to insulin therapy within maximum 6 weeks. These patients can be easily differentiated both from type 2 and from the slowly progressing type 1 subtype. We suppose that the pathomechanism of this type of diabetes differs from the classical insulin-dependent form, beginning in young age. Topics: Age Factors; Aged; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Middle Aged | 1998 |
Spontaneous hypoglycaemia after pancreas transplantation in Type 1 diabetes mellitus.
Hypoglycaemia is an important complication of insulin treatment in Type 1 diabetes mellitus (DM). Pancreas transplantation couples glucose sensing and insulin secretion, attaining a distinctive advantage over insulin treatment. We tested whether successful transplantation can avoid hypoglycaemia in Type 1 DM. Combined kidney and pancreas transplanted Type 1 DM who complied with good function criteria (KP-Tx, n = 55), and isolated kidney or liver transplanted non-diabetic subjects on the same immunosuppressive regimen (CON-Tx, n = 14), underwent 1-day metabolic profiles in the first 3 years after transplantation, sampling plasma glucose (PG) and pancreatic hormones every 2 hours. KP-Tx had lower PG than CON-Tx in the night and in the morning and higher insulin concentrations throughout the day. KP-Tx had lower PG nadirs than CON-Tx (4.40+/-0.05 vs 4.96+/-0.16 mmol l(-1), ANOVA p = 0.001). Nine per cent of KP-Tx had hypoglycaemic values (PG < or = 3.0 mmol l(-1)) in the profiles, both postprandial and postabsorptive, whereas none of CON-Tx did (p < 0.02). In conclusion, after pancreas transplantation, mild hypoglycaemia is frequent, although its clinical impact is limited. Compared to insulin treatment in Type 1 DM, pancreas transplantation improves but cannot eliminate hypoglycaemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Humans; Hypoglycemia; Insulin; Kidney Failure, Chronic; Kidney Transplantation; Liver Transplantation; Male; Pancreas Transplantation; Postoperative Complications; Time Factors | 1998 |
Type 1 diabetes in insulin-treated adult-onset diabetic subjects.
The frequency of autoimmune features was compared in adult-onset diabetic subjects either requiring insulin treatment within 12 months of diagnosis or progressing to insulin therapy after a latency of at least 5 years. Adult-onset insulin-treated diabetic subjects were sampled from the population-based Canterbury Diabetes Registry (n = 1580). There were 237 (15%) registrants who met the study criteria of age < 75 years at 1 January 1993, age at diagnosis of diabetes > or = 45 years and duration of diabetes between 5 and 15 years; 101 subjects commenced insulin 5-15 years after diagnosis (group 1) and 80 subjects commenced insulin within 1 year of diagnosis (group 2). C-peptide levels, islet cell antibodies (ICA) and antibodies against glutamic acid decarboxylase (anti-GAD) were determined in all individuals from group 1 (n = 27) and group 2 (n = 23) who agreed to be recruited to the study. The group 1 and group 2 samples did not differ significantly in their demographic characteristics, nor were they different from the two groups from which they were drawn (mean age, 64.2 years; age at diagnosis, 53.5 years; duration of diabetes, 10.7 years; body mass index, 28.6 kg/m2). Overall, 12 of the 50 (24%) study subjects tested positive for anti-GAD; 43% (10) of group 2 subjects were anti-GAD positive compared with only 7.4% (2) of group 1 subjects (P < 0.01). Postprandial C-peptide levels were significantly lower in group 2 subjects compared with group 1 subjects (627 vs 1124 pM, P < 0.05). All subjects were ICA negative. These observations suggest that autoimmune destruction of beta-cells explains early requirement for insulin in adult-onset diabetes. Topics: Age of Onset; Aged; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Glutamate Decarboxylase; Humans; Insulin; Islets of Langerhans; Middle Aged | 1998 |
Classification of newly-onset IDDIM and NIDDIM in subjects aged 25-45 years in Sudan.
To investigate the ability of classifying diabetes mellitus with clinical and biochemical characteristics at diagnosis in 25-45 years old patients.. We determined age, body mass index (BMI), ICA, fasting C-peptide and HbA1c at diagnosis, and after 4-27 months follow up, these variables were related to the type of treatment.. Omdurman Teaching Hospital, Sudan.. Eighty-six consecutive newly diagnosed diabetic patients, according to WHO criteria, were included.. At diagnosis, 27 patients (31.4%) were treated with insulin and 59 (68.6%) with diet and/or oral hypoglycaemic agents (OHA). Insulin-treated patients at diagnosis were younger, had lower BMI and higher HbA1c. In the non-insulin treated group at diagnosis, ICA-negative patients (n = 54) had higher fasting C-peptide (P < 0.05) than ICA-positive. The treatment was changed from insulin to diet and/or OHA in 17 patients, and to insulin in six patients. Patients who discontinued insulin had already at diagnosis higher BMI and higher fasting C-peptide concentration (P < 0.005 and P < 0.05, respectively) than patients remained on insulin. The positive predictive values for insulin treatment of ICA positivity, low fasting C- peptide, and low BMI were 90, 78 and 73%, respectively. The sensitivity, specificity and positive predictive values for these variables in concurrence were, respectively, 85, 92 and 69%.. The clinical classification of newly- diagnosed young Sudanese patients was satisfactory. With regular follow up and early commencement of appropriate treatment, good glycaemic control is certainly attainable. BMI is potentially valuable for the clinical classification in such patients. ICA and fasting serum C-peptide facilitate the choice of insulin treatment, but cost is a limit to large-scale use of these tests. Topics: Adult; Age Factors; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Middle Aged; Sudan | 1998 |
Prader-Willi syndrome with elevated follicle stimulating hormone levels and diabetes mellitus.
A 21 -year-old man with Prader-Willi syndrome (PWS) was hospitalized due to hyperglycemia. After diet therapy and transient insulin administration, his blood glucose levels improved. Based on the fact that his urinary C-peptide levels increased, the diabetes mellitus may have been due to insulin resistance with obesity. In addition, his testes had become atrophied. Testosterone levels remained low even after human chorionic gonadotropin (HCG) administration. Luteinizing hormone (LH) levels were also low after LH releasing hormone (LHRH) administration. The LH response increased slightly after daily LHRH administration, indicating hypothalamic hypogonadism. Follicle stimulating hormone (FSH) levels were, however, high and increased after LHRH administration. The selective FSH elevation may have been due to the accompanying idiopathic oligospermia. Topics: Adult; Blood Glucose; C-Peptide; Chorionic Gonadotropin; Diabetes Mellitus, Type 1; Follicle Stimulating Hormone; Follow-Up Studies; GABA Modulators; Gonadotropin-Releasing Hormone; Humans; Injections, Intravenous; Insulin; Luteinizing Hormone; Male; Prader-Willi Syndrome; Radioimmunoassay; Testosterone | 1998 |
Anti-insulin antibodies and birth weight in pregnancies complicated by diabetes.
Free insulin cannot cross the placenta but insulin complexed to anti-insulin antibodies has been demonstrated in cord blood. We studied whether antibody-bound insulin in diabetic patients can evoke fetal macrosomia independently of maternal metabolic control. In 457 non insulin-treated controls and 173 insulin-treated diabetic patients we measured 1187 anti-insulin antibody levels and maternal blood glucose, maternal fructosamine, cord blood insulin, cord blood C-peptide, cord blood fructosamine and amniotic fluid insulin. Mean anti-insulin antibody levels in maternal blood and cord blood were significantly higher in insulin treated diabetic patients (4.6 and 5.4 U/ml) than in controls (1.8 and 1.7 U/ml) with maxima of 89.2 in maternal and 120.0 U/ml in cord blood, respectively. In insulin treated diabetic patients 16.6% (maternal blood) and 22% (cord blood) anti-insulin antibody levels were above the 97th percentile. There was a high significant correlation between maternal and cord blood anti-insulin antibodies (R = 0.987, P = < 0.0001), but no correlation of anti-insulin antibodies with maternal (glucose, fructosamine) or fetal (insulin, C-peptide, and fructosamine in cord blood, amniotic fluid insulin) metabolic parameters. While maternal and fetal metabolic parameters correlated with birth weight neither maternal nor cord blood anti-insulin antibody levels correlated with birth weight. These findings do not support the hypothesis that maternal anti-insulin antibodies independently influence fetal weight. Topics: Amniotic Fluid; Autoantibodies; Birth Weight; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Fetal Blood; Fructosamine; Humans; Infant, Newborn; Insulin; Pregnancy; Pregnancy in Diabetics | 1998 |
Exercise increases insulin clearance in healthy man and insulin-dependent diabetes mellitus patients.
Exercise is known to decrease insulin secretion, but the effect on insulin clearance is unclear. We examined the effect of exercise in insulin clearance with euglycaemic insulin clamp in 28 healthy men either 12 h after a marathon run (n = 14) or 44 h after a 2-h treadmill exercise (n = 14), and in seven insulin-dependent diabetes mellitus (IDDM) patients 12 h after a marathon run, and after a resting, control day. During the post-exercise insulin infusion, steady-state plasma insulin concentration was reduced by 9% in healthy men after both types of exercise, and by 16% in the diabetic subjects compared with the control study (P < 0.05 in all). In healthy men, C-peptide concentrations were more than one-third lower during insulin infusion, both after the marathon run (P < 0.001) or treadmill exercise (P < 0.02) compared with the control study. Insulin clearance was significantly increased by exercise both in healthy men (9% P < 0.05) and in IDDM subjects (15%, P < 0.05). After exercise, endogenous insulin secretion in healthy men is reduced and insulin clearance is enhanced both in healthy men and in IDDM patients. Decreased insulin availability may allow enhanced muscle lipid utilization and spare glucose after long-term exercise. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exercise; Fasting; Humans; Hyperinsulinism; Insulin; Male; Running; Triglycerides | 1997 |
Unchanged insulin absorption after 4 days' use of subcutaneous indwelling catheters for insulin injections.
Since 1985, we have used indwelling catheters (Insuflon, Maersk Medical, Lynge, Denmark; Chronimed, Minnetonka, MN) to lessen pain when injecting insulin. However, some patients experience a rise in blood glucose after using indwelling catheters for a few days. We therefore studied the absorption of 125I-labeled insulin when using indwelling catheters.. Five men and five women participated (age 18-25 years, C-peptide negative, HbA1c 9.0 +/- 1.0% [mean +/- SD, DCA-2000 method], diabetes duration 5-21 [median 9.5] years). After thyroid blockage with potassium iodide, we injected 5IU of 125I-labeled short-acting insulin subcutaneously in the abdomen ("ordinary injection") and 5 IU on the contralateral side through an indwelling catheter ("catheter injection"). The injection/insertion area was free of lipohyper- and lipohypotrophies. Disappearance rate was measured for 180 min with a gamma camera. The patients injected all premeal injections of short-acting insulin through the same indwelling catheter in the following 4 days. The investigation procedure was repeated day 3 and 5.. We found no statistically or clinically (95% CI) significant difference in residual activity of 125I-insulin after 60 min or in time for 50% of the injected depot to disappear (T-50%) among catheter injections on day 1, 3, and 5; ordinary injections on days 1, 3, and 5; or catheter and ordinary injections on days 1, 3, and 5, respectively. HbA1c correlated both to T-50% (r = 0.73, P = 0.016) and residual activity of 125I-insulin after 60 min (r = 0.69, P = 0.028), indicating that patients with a slower absorption will have a less ideal metabolic control when using premeal bolus injections.. We conclude that using indwelling subcutaneous catheters for insulin injections for up to 4 days does not affect the absorption of short-acting insulin. Topics: Absorption; Adolescent; Adult; C-Peptide; Catheters, Indwelling; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin; Insulin, Regular, Pork; Iodine Radioisotopes; Male | 1997 |
Fluctuations in GAD65 antibodies after clinical diagnosis of IDDM in young children.
To investigate whether the presence of GAD antibodies at onset of IDDM correlates to a more aggressive rate of beta-cell destruction after clinical onset.. We studied GAD antibodies at onset of disease, after 1 year, and after 6 years in 33 consecutively referred children (mean age 8.08, range 1.7-16.3). In a subset of 11 patients, GAD antibodies were studied very frequently. The correlation between GAD antibodies and clinical parameters, including glycosylated hemoglobin, residual insulin secretion, and insulin dosage, was evaluated.. GAD antibody titers were highly variable. Four patients became GAD antibody positive weeks to years after clinical onset. Other patients switched between testing positive and negative for GAD antibodies shortly after clinical onset. No correlation was found between the presence of GAD antibodies and the rate of beta-cell destruction, but patients with high GAD antibody indexes at onset had significantly higher glycosylated hemoglobin levels.. GAD antibodies at clinical onset do not predict the rate of beta-cell destruction in young children with newly diagnosed IDDM. The highly variable GAD antibody levels suggest variation of the autoimmune process. Topics: Autoantibodies; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Follow-Up Studies; Glutamate Dehydrogenase; Humans; Infant; Insulin Infusion Systems; Longitudinal Studies; Time Factors | 1997 |
Are young age and insulin treatment enough to diagnose IDDM?
Topics: Adolescent; Adult; Age Factors; Aged; Biomarkers; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Europe; Humans; Insulin; Israel; Middle Aged | 1997 |
Clinical hypoglycemia before diabetes is rare. A study of identical twins.
Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Diseases in Twins; Female; Glucose Intolerance; Humans; Hypoglycemia; Insulin; Longitudinal Studies; Self Administration; Time Factors; Twins, Monozygotic | 1997 |
Bone modeling indexes at onset and during the first year of follow-Up in insulin-dependent diabetic children.
Osteopenia has been described as a complication of insulin-dependent diabetes mellitus (IDDM). We measured bone modeling indexes during the first year of IDDM. At each time point the values obtained from diabetic children have been compared with those of control subjects. We selected 27 prepubertal children with IDDM (6.35 +/- 2.16 years). We also enrolled 30 healthy prepubertal children of comparable age (5.85 +/- 3.05 years). Height, height standard deviation scores, glycated haemoglobin (HbA1C), basal c-peptide concentrations, insulin dose, serum concentrations of procollagen type I C-terminal propeptide (PICP), and collagen type I C-terminal telopeptide (ICTP) were measured at onset of IDDM and at 3, 6 and 12 months. ICTP was in the normal range at onset of IDDM and decreased during the follow-up to reach a significant difference compared to controls after 3, 6 and 12 months of insulin treatment (P < 0.04). PICP concentrations increased significantly at 3 months (P = 0.05) compared to onset. At 3 and 12 months PICP values were significantly higher than those of control children (P = 0.04). Correlations were found between PICP concentrations and HbA1C and c-peptide at onset of diabetes (r = -0.45 and r = 0.47, respectively). Bone formation at onset of IDDM is not impaired; the introduction of insulin therapy, together with the achievement of a good metabolic control, determines an increase of bone matrix formation coupled with a decrease of bone resorption, that determines a positive balance of bone modeling. Topics: Adolescent; Biomarkers; Body Height; Body Weight; Bone Development; Bone Diseases, Metabolic; C-Peptide; Child; Cohort Studies; Collagen; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Male; Peptide Fragments; Procollagen; Reference Values; Regression Analysis; Time Factors | 1997 |
Glucagon enhances the direct suppressive effect of insulin on hepatic glucose production in humans.
The present study examines the role of glucagon in modulating the hepatic and extrahepatic effects of insulin on hepatic glucose production (HGP). We infused glucagon at a constant rate (0.65 ng x kg(-1) x min(-1)) during equimolar portal and peripheral insulin delivery in seven healthy males by our previously published tolbutamide infusion method. In contrast to our previous study, in which glucagon fell by approximately 30% during hyperinsulinemia and suppression of HGP was significantly greater with equimolar peripheral than with portal insulin delivery, HGP was actually suppressed to a lesser extent with peripheral insulin delivery (69 +/- 10%) than when insulin was delivered portally (76 +/- 5%, P < 0.05). To further examine whether glucagon was enhancing the effect of portal insulin, in four additional individuals HGP was suppressed to a greater extent during a tolbutamide infusion when glucagon was administered continuously throughout the basal and hyperinsulinemic periods than when glucagon was infused during the basal period only; HGP suppressed by 63 +/- 3 vs. 52 +/- 3%, respectively, P = 0.02). Tolbutamide had no effect on HGP when infused into three C-peptide-negative individuals with type I diabetes during a low-dose insulin and glucagon infusion. These data suggest that glucagon levels are an important determinant of the balance between insulin's direct and indirect effects on HGP, with glucagon likely potentiating the direct hepatic effect of insulin. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Synergism; Glucagon; Glucose; Humans; Insulin; Liver; Liver Circulation; Male; Tolbutamide | 1997 |
Discriminative capacity of fasting C-peptide levels in a functional test according to different criteria of response to a stimulus. A study of Brazilian insulin-dependent diabetic patients.
In order to study the discriminative capacity of the C-peptide basal values (BV) in a functional test, we analysed the C-peptide response curve after a mixed meal in 26 insulin-dependent patients. The five criteria of response used were: (1) any increment after the stimulus; (2) percentual increment above 21%; (3) absolute increment above 0.35 ng/ml; (4) incremental area above 42.76 ng.min.ml-1, and (5) peak value above 2.16 ng/ml. Considering the first two criteria, many patients showed positive responses, in the diabetic group as a whole and when we analysed patients with BV > or = 0.74 ng/ml and < 0.74 ng/ml separately. When we applied only the last three criteria the number of positive responses was considerably smaller. Moreover, the majority of patients with BV < 0.74 ng/ml could not increase their levels over the ones established above. In patients with BV > or = 0.74 ng/ml, the number of positive and negative responses were similar. The comparison between the subgroups achieves statistical significance only for incremental area (chi 2 = 3.55, p = 0.03). We conclude that the functional test was important mainly for patients with BV > or = 0.74 ng/ml, and could have been omitted for patients with BV < 0.74 ng/ml. The best criteria of response were those based on the mean minus two standard deviations of each parameter in a non-diabetic group (the last three criteria), especially the incremental area. Topics: Adult; Biomarkers; Blood Glucose; Body Mass Index; Brazil; C-Peptide; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Humans; Insulin; Islets of Langerhans; Male | 1997 |
Presence of anti-pituitary antibodies and GAD antibodies in NIDDM and IDDM.
To evaluate the clinical significance of the presence of anti-pituitary antibodies (APAs) in patients with NIDDM or IDDM and to examine the relationship of APAs to GAD antibodies (GADAs).. Serum samples were obtained from patients with NIDDM and IDDM. APAs, determined by Western blot analysis, and GADAs, determined by radioimmunoassay, were detected in the patients' sera and control sera. Urinary levels of C-peptide (U-CPR) were measured.. The prevalence of APAs was significantly higher in patients with NIDDM (24.2%) or IDDM (56.8%) than in healthy control subjects (6%). In patients with NIDDM, the levels of U-CPR were significantly lower, and the prevalence of insulin deficiency was higher in APA+ patients than in APA- patients.. This is the first study to demonstrate that the prevalence of APAs is increased in patients with NIDDM and IDDM. The presence of APAs may be related to reduced secretion of insulin in NIDDM patients. Topics: Adolescent; Adult; Autoantibodies; Blotting, Western; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Male; Middle Aged; Pituitary Gland; Radioimmunoassay; Reference Values | 1997 |
Development of an isotope dilution assay for precise determination of insulin, C-peptide, and proinsulin levels in non-diabetic and type II diabetic individuals with comparison to immunoassay.
We describe the application of a stable isotope dilution assay (IDA) to determine precise insulin, C-peptide, and proinsulin levels in blood by extraction from serum and quantitation by mass spectrometry using analogues of each target protein labeled with stable isotopes. Insulin and C-peptide levels were also determined by immunoassay, which gave consistently higher results than by IDA, the relative difference being larger at low concentrations. Insulin, C-peptide, and proinsulin levels were all shown by IDA to be higher in type II diabetics than in non-diabetics, with mean values rising from 22 (+/- 2) to 92 (+/- 8), 335 (+/- 11) to 821 (+/- 24), and 6 (+/- 1) to 37 (+/- 3) pM, respectively. Interestingly, the ratio between IDA and immunoassay values for insulin levels increased from 1.3 in non-diabetics to 1.7 in type II diabetics. The ratio between proinsulin and insulin levels by IDA increased from 0.24 in non-diabetics to 0.36 in type II diabetics, whereas the ratio between C-peptide and insulin levels by IDA decreased from 17.6 to 10.7. This disproportionate change in protein levels between different types of individuals has implications for the metabolism of insulin in the diabetics studied (type II) and suggests that C-peptide levels are not always a reliable guide as to pancreatic insulin secretion. In addition, levels of the 33-residue C-peptide (partially trimmed form) were shown to be less than 10% that of the fully trimmed 31-residue C-peptide levels, and we tested IDA in a clinical context by two post-pancreatic graft studies. IDA was shown to give direct, positive identification of the target protein with unrivaled accuracy, avoiding many of the problems associated with present methodology for protein determination. Topics: C-Peptide; Chromatography, High Pressure Liquid; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Immunoassay; Insulin; Male; Middle Aged; Pancreas Transplantation; Proinsulin | 1997 |
Abnormal myocardial kinetics of 123I-heptadecanoic acid in subjects with impaired glucose tolerance.
Increased triglyceride accumulation has been observed in the diabetic heart, but it is not known whether the abnormalities in myocardial fatty acid metabolism differ between insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetic patients or whether they are present even prior to overt diabetes. Therefore, we studied myocardial fatty acid kinetics with single-photon emission tomography using 123I-heptadecanoic acid (HDA) in four groups of men: impaired glucose tolerance (IGT) (n = 13, age 53 +/- 2 years, mean +/- SEM), IDDM (n = 8, age 43 +/- 3 years), NIDDM (n = 10, age 51 +/- 2 years) and control subjects (n = 8, age 45 +/- 4 years). Echocardiography and myocardial perfusion scintigraphy (IGT and NIDDM groups) were performed to study cardiac function and flow. In the IGT subjects, myocardial HDA beta-oxidation index was reduced by 53% (4.6 +/- 0.4 vs 9.7 +/- 1.0 mumol .min-1.100 g-1, p < 0.01) and HDA uptake by 34% (3.7 +/- 0.2 vs 5.6 +/- 0.3% of injected dose 100g, p < 0.01) compared with the control subjects. The fractional HDA amount used for beta-oxidation was lower in the IGT compared with the control subjects (43 +/- 4 vs 61 +/- 4%, p < 0.05). NIDDM patients also tended to have a lowered HDA beta-oxidation index, whereas IDDM patients had similar myocardial HDA kinetics compared to the control subjects. Myocardial perfusion imaging during the dipyridamole-handgrip stress was normal both in the IGT and NIDDM groups, indicating that abnormal myocardial perfusion could not explain abnormal fatty acid kinetics. In conclusion, even before clinical diabetes, IGT subjects show abnormalities in myocardial fatty acid uptake and kinetics. These abnormalities may be related to disturbed plasma and cellular lipid metabolism. Topics: Adult; Analysis of Variance; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Echocardiography; Fatty Acids; Fatty Acids, Nonesterified; Glucagon; Glucose Intolerance; Heart; Humans; Iodine Radioisotopes; Male; Middle Aged; Models, Cardiovascular; Myocardium; Reference Values; Tissue Distribution; Tomography, Emission-Computed; Ventricular Function, Left | 1997 |
Autoantibodies in relation to residual insulin secretion in children with IDDM.
To elucidate whether autoantibodies can be used to predict the intensity of autoimmune beta-cell destruction, we determined both C-peptide and autoantibodies (islet cell antibodies (ICA), insulin autoantibodies (IAA), islet cell surface antibodies (ICSA) and antibodies to glutamic acid decarboxylase (GADA)). In 89 diabetic children and adolescents at diagnosis at the age of 1.2-16.6 years (mean +/- S.D., 9.0 +/- 4.5). Only 12/89 (14%) had no autoantibodies at diagnosis, while 2 patients (2%) had all 4 autoantibodies. There was a positive correlation between GADA and ICA (P < 0.01). At diagnosis 70% of the patients had GADA, most common in patients above the age of 8 years at diagnosis (P < 0.001), and with higher GAD-index in girls (P < 0.05). ICA was detected in 63%, most common in the older age groups (P = 0.04). ICSA seen in 22% of the patients as well as IAA (detected in 32%) were most common < 8 years of age (P = 0.06, P = 0.08, respectively). Children with autoantibodies had similar C-peptide levels through the follow up period as children of the same sex and age without antibodies, except for patients with ICSA alone or in combination with other autoantibodies who tended to have higher C-peptide levels. We conclude that not even combinations of autoantibodies can be used to predict beta-cell destruction in IDDM patients. Topics: Adolescent; Age Factors; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Infant; Insulin; Insulin Antibodies; Insulin Secretion; Islets of Langerhans; Male; Predictive Value of Tests; Sex Characteristics; Time Factors | 1997 |
Laparoscopic cholecystectomy and islet cell transplantation in a type I diabetic patient.
Topics: C-Peptide; Cholecystectomy, Laparoscopic; Cholelithiasis; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged | 1997 |
Intravenous glucose tolerance tests after porcine islet auto- and allotransplantation.
Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Insulin; Islets of Langerhans Transplantation; Pancreatectomy; Swine; Transplantation, Autologous; Transplantation, Homologous | 1997 |
Immunoprotection provided by the bioartificial pancreas in a xenogeneic host.
Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Dogs; Graft Survival; Insulin; Insulin Secretion; Pancreas, Artificial; Pancreatectomy; Swine; Transplantation, Heterologous | 1997 |
An attempt to reverse diabetes by delayed islet cell transplantation in humans.
Topics: Adult; Bone Marrow Transplantation; C-Peptide; Cadaver; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Time Factors; Tissue Donors; Transplantation Chimera | 1997 |
Comparison of transplanted islets in patients with functioning versus nonfunctioning allografts.
Topics: C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drug Therapy, Combination; Humans; Immunosuppressive Agents; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Retrospective Studies; Time Factors; Transplantation, Homologous; Treatment Failure; Treatment Outcome | 1997 |
Sensitization to HLA antigens in islet recipients with failing transplants.
Topics: Antibody Specificity; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Histocompatibility Antigens Class I; Histocompatibility Testing; Humans; Islets of Langerhans Transplantation; Isoantibodies; Retrospective Studies; T-Lymphocytes; Treatment Failure | 1997 |
Glucose tolerance status and severity of coronary artery disease in men referred to coronary arteriography.
Increasing attention is being paid to disturbances in glucose metabolism as key explanatory factors for the development of coronary artery disease. We studied the prevalence of impaired glucose tolerance and non-insulin-dependent diabetes and the levels of plasma insulin after an oral glucose tolerance test in 99 men with heart disease but without a history of diabetes referred to coronary arteriography; we also compared the outcome with a matched control group (n = 116). The severity of atherosclerosis in coronary angiograms was evaluated according to glucose tolerance status. Among the 99 patients with coronary artery disease, 37.4% had an abnormal oral glucose tolerance test result, whereas only 18.1% of the control group had an abnormal result (p < 0.01). Moreover, patients with heart disease and normal glucose tolerance were hyperinsulinemic compared with the control group (p < 0.01). By analysis of variance no statistically significant difference in severity of coronary atherosclerosis on coronary angiograms was found. In conclusion, we demonstrated frequent disturbances in glucose metabolism indicating insulin resistance in patients with ischemic heart disease without a history of diabetes, but we could not demonstrate a relation between these disturbances and degree of coronary atherosclerosis. Topics: Adult; Aged; Albuminuria; Analysis of Variance; Blood Glucose; C-Peptide; Case-Control Studies; Coronary Angiography; Coronary Artery Disease; Coronary Disease; Diabetes Mellitus, Type 1; Glucose; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Male; Middle Aged; Myocardial Ischemia; Prevalence; Proinsulin | 1997 |
Poor beta-cell function after the clinical manifestation of type 1 diabetes in children initially positive for islet cell specific autoantibodies. The Childhood Diabetes in Finland Study Group.
The prognostic significance of islet cell specific autoantibodies at the diagnosis of Type 1 (insulin-dependent) diabetes mellitus for the persistence of residual beta-cell function over the first 2 years of clinical disease was evaluated in a prospective population-based study. Seven hundred and eighty probands, aged 0.8-14.9 years, were examined for islet cell antibodies (ICA) and insulin autoantibodies (IAA), while 769 probands were studied for antibodies to glutamic acid decarboxylase (GAD65A). They were subsequently observed for 2 years. Lower serum C-peptide concentrations and higher requirement of exogenous insulin during the follow-up period were observed in the group of probands positive for at least one of the antibodies, especially for ICA or IAA. We conclude that the residual beta-cell function after the presentation of Type 1 diabetes is less in children initially positive for islet cell specific autoantibodies than in those testing negative at diagnosis. This might reflect possible heterogeneity in the pathogenesis of childhood diabetes. It also demonstrates that ICA and IAA negativity at the diagnosis of Type 1 diabetes is not associated with a smaller amount of functioning beta-cell mass, but the absence of antibodies probably reflects a slower beta-cell destructive process and a longer duration of preclinical disease. Topics: Adolescent; Age Factors; Analysis of Variance; Antibody Specificity; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Finland; Follow-Up Studies; Glutamate Decarboxylase; Humans; Hydrogen-Ion Concentration; Hypoglycemic Agents; Infant; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Prospective Studies; Sex Factors | 1997 |
Lipolytic responsiveness to epinephrine in nondiabetic and diabetic humans.
To determine whether the sensitivity of adipose tissue lipolysis to catecholamines is increased in poorly controlled insulin-dependent diabetes, the lipolytic response to epinephrine was measured in seven nondiabetic volunteers and seven poorly controlled diabetic subjects with use of [1-(14)C]palmitate as a tracer. Subjects received sequential 1-h infusions of epinephrine, which produced epinephrine concentrations of approximately 1,000, approximately 1,750, approximately 3,500, and approximately 6,000 pmol/l. A pancreatic clamp was used to maintain constant plasma hormone levels. Concentration-response curves were constructed for each subject from the integrated lipolytic response during each epinephrine infusion. There was no difference in maximal lipolytic response (117 +/- 19 vs. 152 +/- 11 mumol.kg-1.h-1) or in maximally effective (3,171 +/- 267 vs. 3,357 +/- 349 pmol/l) or half-maximally effective (1,081 +/- 109 vs. 1,015 +/- 120 pmol/l) epinephrine concentrations between nondiabetic and diabetic subjects, respectively (all P = NS). In control subjects, maximum beta-hydroxybutyrate concentrations were achieved at lower epinephrine concentrations than those required for a maximum lipolytic effect. Thus, under pancreatic clamp conditions, the lipolytic response to epinephrine in nondiabetic and diabetic subjects was similar. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Carbon Radioisotopes; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Female; Humans; Hydroxybutyrates; Infusions, Intravenous; Insulin; Lipolysis; Male; Palmitic Acid; Radioisotope Dilution Technique; Reference Values | 1997 |
Insulin resistance with altered secretory kinetics and reduced proinsulin in cystic fibrosis patients.
Impaired glucose tolerance and secondary diabetes are frequent in older patients with cystic fibrosis (CF), associated with increased frequency of infections and reduced life expectancy. Studies on the pathophysiology of islet cell secretion in CF are a prerequisite for a scientifically based therapeutic approach.. Oral glucose tolerance tests were performed in 71 patients (14.2 +/- 0.5 years; mean +/- SE) and 56 control subjects (16.5 +/- 0.9 years). Glucose, insulin, C-peptide, and proinsulin were measured every 30 min.. Glucose tolerance in CF patients was classified as normal (NGT, n = 48), impaired (IGT, n = 14), or diabetic (DM, n = 9). Even in CF patients with NGT, blood glucose was significantly elevated at 30, 60, and 90 min of the test. Surprisingly, the secretory responses of insulin and C-peptide were not reduced in CF patients with IGT or DM compared with both healthy controls or CF patients with normal glucose tolerance. However, peak insulin concentration was reached at 90 min in CF-IGT or CF-DM patients compared with 30 min in controls. The ratio of glucose to insulin, an indicator of insulin resistance, increased in CF patients with progression of carbohydrate intolerance. Proinsulin was significantly reduced in all CF patients compared with controls (p < 0.001; Wilcoxon's rank sum test).. In CF patients with impaired glucose tolerance or diabetes, integrated insulin release is not diminished, indicating that insulin resistance is likely to contribute to hyperglycemia in CF patients with IGT or DM. Reduced proinsulin levels in CF patients are compatible either with enhanced conversion of proinsulin to insulin in compensation for reduced beta-cell mass, or enhanced clearance of proinsulin. Topics: Adolescent; Blood Glucose; C-Peptide; Cohort Studies; Cystic Fibrosis; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Male; Proinsulin; Reference Values; Time Factors | 1997 |
Nocturnal hypoglycemia in children and adolescents with insulin-dependent diabetes mellitus: prevalence and risk factors.
To evaluate the prevalence and risk factors of nocturnal hypoglycemia (NH) in children and adolescents with insulin-dependent diabetes mellitus.. A total of 150 patients, 87% of whom were receiving conventional therapy, were admitted to the hospital for one night. Blood glucose (BG) levels were measured hourly from 10 PM to 8 AM.. The prevalence of NH was 47%; NH was asymptomatic in 49% of the cases. Risk factors were as follows: at least two episodes of severe hypoglycemia from onset of insulin-dependent diabetes mellitus (p = 0.0004), insulin dosage > 0.85 IU/kg per day (p = 0.02), more than 5% of BG measurements < or = 3.3 mmol/L during the last month of monitoring (p = 0.04). The risk decreased significantly with age (p = 0.0001). Both high predictive values and significant relative risk were found for BG thresholds < or = 5.2 mmol/L at dinner time (p < 0.0001) and < or = 6.7 mmol/L at 7 AM (p < 0.0001). When BG values at 10 PM were used, prediction of NH was weak.. Nocturnal hypoglycemia occurred frequently in children and adolescents with insulin-dependent diabetes mellitus. Our study found risk factors that will help pediatricians to identify those children with a high risk of NH. Especially in these patients, counseling based on the BG values before dinner and early in the morning is indicated to reduce the prevalence of NH. Topics: Adolescent; Age Factors; Blood Glucose; C-Peptide; Child; Child, Preschool; Circadian Rhythm; Cohort Studies; Counseling; Diabetes Mellitus, Type 1; Eating; Female; Forecasting; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Male; Predictive Value of Tests; Prevalence; Puberty; Risk Factors; Time Factors | 1997 |
New insulins and other possible therapeutic approaches.
Topics: Amyloid; C-Peptide; Diabetes Mellitus, Type 1; Drug Delivery Systems; Humans; Hypoglycemic Agents; Insulin; Insulin Lispro; Insulin-Like Growth Factor I; Islet Amyloid Polypeptide | 1997 |
A 10-year prospective study of IDDM patients subjected to combined pancreas and kidney transplantation or kidney transplantation alone.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Kidney Transplantation; Pancreas Transplantation; Prospective Studies; Quality of Life; Time Factors | 1997 |
Early experience with a long-distance collaborative human islet transplant programme.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Germany; Glycated Hemoglobin; Graft Survival; Humans; Insulin; International Cooperation; Islets of Langerhans Transplantation; Male; Postoperative Complications; Sweden; Time Factors; Tissue and Organ Procurement | 1997 |
Influence of residual C-peptide secretion on nocturnal serum TSH peak in well-controlled diabetic patients.
Several alterations in hypothalamo-pituitary-thyroid (HPT) function have been described in diabetes mellitus and have been attributed to metabolic decompensation. The present study was performed in order to establish whether residual endogenous insulin secretion in patients with insulin-dependent diabetes mellitus (IDDM) may play a role in the control of HPT function.. The nocturnal (2230 h-0200 h) serum TSH surge, the TSH response to TRH (200 microgram as an i.v. bolus) and serum free thyroid hormone levels were evaluated in C-peptide positive (CpP) (subjects with residual detectable endogenous pancreatic beta-cell activity) and C-peptide negative (CpN) patients both before and after optimization of metabolic status by 3 days of treatment with continuous subcutaneous insulin infusion, and in normal controls. TSH response to TRH and serum free thyroid hormone levels were assessed in the morning.. Twenty male diabetic patients hospitalized to achieve a better control of hyperglycaemia were subdivided into 10 CpP (age: 33 +/- 1.5 years (mean +/- SE); body mass index (BMI): 22.6 +/- 0.3) and 10 CpN (age: 32 +/- 1.7 years; BMI: 22.5 +/- 0.4) patients. Nine normal men (age: 34.0 +/- 1.2 years; BMI: 23.1 +/- 0.4) served as controls.. The nocturnal serum TSH peak was measured by dividing the highest night-time TSH value by the next morning TSH value and then multiplying by 100. Serum TSH levels were measured in samples taken just before (time 0) and 30 minutes, after TRH administration. Serum free thyroid hormone levels were measured in samples taken at time 0 of the TRH test.. Before improvement of hyperglycaemia, CpP and CPN patients showed similar alterations in HPT function; i.e. serum free T3 levels and TSH responses to TRH were lower than normal; the nocturnal TSH surge was absent. Correction of hyperglycaemia normalized all examined HPT parameters in CpP diabetics, whereas normalization in serum free T3 levels and pituitary TSH responsiveness to TRH in CpN patients was not accompanied by restoration of the nocturnal TSH peak.. These data indicate that the absence of residual pancreatic beta-cell function in patients with insulin-dependent diabetes mellitus is associated with neuroendocrine dysfunction in the regulation of circadian TSH secretion, which is not reversible after restoration of good glycaemic control. Topics: Adult; Analysis of Variance; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Humans; Hypothalamo-Hypophyseal System; Insulin; Male; Pituitary-Adrenal System; Thyrotropin; Thyrotropin-Releasing Hormone; Triiodothyronine | 1997 |
[Measurement of proinsulin, insulin and C-peptide in human blood by high performance liquid chromatography].
The technique of measuring insulin, proinsulin, and C-peptide in human blood by high-pressure liquid chromatography is described. Donors, subjects with abnormal glucose tolerance, and patients with type I diabetes were examined. The main advantage of the method over radioimmunoassay and enzyme immunoassay is the possibility of simultaneous differentiated measurement of human insulin and animal hormone administered parenterally, and separation of insulin and its precursor on the basis of difference in molecular weight and charge of molecules. The results indicate that patients with type I diabetes retain the secretion of endogenous insulin, although its level is appreciably lower than in healthy donors, and the structure of its molecules is heterogeneous, which is proven by a biphasic chromatographic peak. Inhibition of proinsulin transformation into insulin is one probable mechanism of impairment of glucose tolerance. High-pressure liquid chromatography can be used at clinical laboratories for examinations of diabetics. Topics: Blood Glucose; C-Peptide; Chromatography, High Pressure Liquid; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Proinsulin | 1997 |
Long-term function (6 years) of islet allografts in type 1 diabetes.
Eight type 1 diabetic patients, ages 29-41 years, with mean diabetes duration of 23 years (range 18-29 years) received islet transplants from 1 to 5 donors. Seven patients had stable kidney allografts 1-11 years before the islet transplant, and one patient had a simultaneous islet-kidney allograft. Patients' blood glucose control was poor as reflected by the mean +/- SD HbA1c of 9.1 +/- 1.7% before transplant. Of the first three patients, two (1 and 3) achieved insulin independence for 36 and 38 days, respectively. Two recipients rejected their islet grafts within 1 month (2 and 8) and therefore were excluded from analysis. The HbA1c and insulin requirement of the six remaining patients who had persistent islet function for more than 60 days was significantly reduced from 9.3 +/- 1.9 to 6.4 +/- 1.0% (P = 0.002) and from 0.75 +/- 0.15 to 0.35 +/- 0.12 U x kg(-1) x day(-1) (P < 0.001), respectively. The two patients with the longest graft survival (4 and 6) achieved a normalization or near-normalization of their HbA1c levels during 6 years in the absence of severe episodes of hypoglycemia. As demonstrated by a decline in C-peptide response during Sustacal challenge tests over a 6-year period, there was a diminution of islet allograft function over time, despite persistence of normal or near normal HbA1c. We concluded that transplantation of allogeneic islets with an islet mass comparable with whole or segmental pancreas transplants in type 1 diabetic patients can result in long-term islet allograft function; further, we concluded that, in conjunction with small dosages of exogenous insulin, a functioning islet allograft can result in near-normalization of blood glucose levels and significant improvement in HbA1c. The occurrence of severe hypoglycemic episodes observed for patients in the Diabetes Control and Complications Trial was not observed in recipients with functioning islet transplants, despite the continuous need for exogenous insulin therapy to sustain normal HbA1c over the 6-year follow-up. The significant improvement in metabolic control observed for the patients described in this study, and the potential to significantly decrease or halt the progression of diabetic complications, support the continued application of islet allotransplantation as a treatment modality for type 1 diabetic patients. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Clamp Technique; Glycated Hemoglobin; Graft Rejection; Graft Survival; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation; Metabolic Clearance Rate; Time Factors; Transplantation, Homologous | 1997 |
Comparison of incidence of insulin-dependent diabetes mellitus in children and young adults in the Province of Turin, Italy, 1984-91. Piedmont Study Group for Diabetes Epidemiology.
To document the incidence of IDDM in the Province of Turin (Italy) in the 8-year period 1984-91 in children (0-14 years) and young adults (15-29 years), in relation to age, sex, monthly-seasonal variability, calendar year and urban/rural area, (all newly diagnosed cases (502) were ascertained through primary and secondary data sources and completeness of ascertainment estimated with the two sample capture-recapture method (99% in childhood and 95% in young adults). The independent effect of age, sex, calendar year, and urban/rural area was estimated with a Poisson regression model. Age-specific incidence rates were 8.42/100,000 (95% CI 7.37-9.62) and 6.72/100,000 (95% CI 5.96-7.58), respectively, in the age groups 0-14 and 15-29 years. Sex differences were evident in young adults, with an almost 1.5-fold increased risk in men (8.37/100,000, 95% CI 7.21-9.71 vs 5.00/100,000, CI 4.09-6.10). Seasonal trend was evident in childhood. Predictors of incidence rates were age, place of residence and interaction between sex and age; no temporal trend was detected. No significant differences were found in the two age-groups with respect to glycaemia, glycosuria, ketonuria, and fasting C-peptide levels. In conclusion, this study shows sex differences in IDDM risk in young adults; 55% of incident cases occurring in young adults; an independent contribution of urban/rural differences to IDDM risk; no temporal trend in 1984-91; a seasonal pattern of incidence in children; no significant differences in clinical presentation between age groups. Topics: Adolescent; Adult; Aging; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Infant; Italy; Ketone Bodies; Male; Risk Factors; Rural Population; Seasons; Sex Characteristics; Urban Population | 1997 |
Anti-GAD65 autoantibody in Taiwanese patients with insulin-dependent diabetes mellitus: effect of HLA on anti-GAD65 positivity and clinical characteristics.
Anti-GAD65 antibody has been studied widely in patients with insulin-dependent diabetes mellitus (IDDM) in many different populations. However, the prevalence of GAD65 autoantibody has not been assessed in Taiwanese patients with IDDM. We therefore characterized GAD65 antibody and investigated the effect of HLA-DR phenotypes on GAD65 autoimmunity and other clinical characteristics in Taiwanese subjects with IDDM.. Two hundred and twenty-five patients (male 102, female 123) with IDDM were recruited. The diagnostic criteria for IDDM were age of onset before 30 years, presence of diabetic ketoacidosis, and insulin-dependency within 3 years of onset. We employed a radioligand method to detect GAD65 antibody. HLA-DR typing was performed by the PCR-SSO techniques. Plasma C-peptide and anti-thyroid microsomal antibody were also measured.. The prevalence of GAD65 antibody according to duration of disease were 50/91 (54.9%), 37/95 (38.9%), 8/24 (33%), and 3/15 (20%) among the groups of duration < or = 5, 6-10, 11-15, and > 15 years, respectively (p = 0.0011). There were no significant differences between GAD(+) and GAD(-) patients in age of onset (11.5 +/- 6.5 and 11.6 +/- 13.4 years, respectively), gender distribution (male:female 39:59 and 58:69, respectively) and percentage with residual beta cell function (38.8% and 29.1%, respectively). Multiple regression analysis revealed that duration of IDDM correlated inversely with residual beta cell function. Earlier onset of IDDM correlated with a loss of beta cell function and a HLA-DR phenotype containing DR3/4, DR3/3 or DR3/9.. Prevalence of GAD65 autoantibody among Taiwanese subjects with IDDM was negatively correlated with duration of disease. Different determinants in the HLA-DR locus contributed to the clinical onset of IDDM but not to GAD autoimmunity. Topics: Adolescent; Age of Onset; Autoantibodies; Autoantigens; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; HLA-DR Antigens; HLA-DR3 Antigen; HLA-DRB1 Chains; Humans; Immunophenotyping; Islets of Langerhans; Male; Prevalence; Regression Analysis; Taiwan; Time Factors | 1997 |
Simultaneous pancreas-kidney transplantation in Hispanic recipients with type I diabetes mellitus and end-stage renal disease.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Florida; Follow-Up Studies; Glycated Hemoglobin; Hispanic or Latino; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Retrospective Studies | 1997 |
Anti-GAD antibodies in Chinese patients with youth and adult-onset IDDM and NIDDM.
An autoimmune basis for the pathogenesis of insulin-dependent diabetes mellitus (IDDM) is supported by the frequent presence of autoantibodies - islet cell antibodies (ICAs) and GAD antibodies (GADab). However, in Chinese patients with clinical IDDM, a low prevalence of ICAs was observed. In non-insulin-dependent diabetic (NIDDM) patients, it has been suggested that the presence of GADab may identify a subset of latent autoimmune diabetes in adults (LADA). We determined the frequency of GADab in a large group of 134 IDDM and 168 NIDDM Chinese patients, and assessed the relation with ICAs status. Results showed that 39.6% IDDM and 16.1% NIDDM patients had GADab, and 20.1% and 4.8%, respectively had detectable ICAs. Frequency of GADab positivity was not influenced by whether the patients had youth or adult-onset IDDM or NIDDM, or by duration of diabetes. NIDDM patients seropositive for GADab shared similar clinical characteristics and fasting C-peptide levels with those who were GADab negative. Presence of GADab therefore did not serve to identify a subgroup of patients with latent or slow-onset IDDM. Half (53%) of our IDDM patients had neither GADab nor ICAs. The reason for this observation is unclear. One theory is that other autoantigens yet to be identified may be contributory. Alternatively, in the Chinese, autoimmunity may not be the major factor in the pathogenesis of IDDM. Topics: Adolescent; Adult; Autoantibodies; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Glutamate Decarboxylase; Humans; Islets of Langerhans; Male; Middle Aged; Singapore | 1997 |
The C-peptide response to a standard mixed meal in a group of Brazilian type 1 diabetic patients.
In order to analyze the different parameters used in the interpretation of C-peptide response in a functional test, we compared a group of 26 type 1 diabetics aged 21.1 +/- 8.2 years, with a diabetes duration of 7.9 +/- 6.7 months, with a group of 24 non-diabetic subjects aged 25.0 +/- 4.4 years. A standard mixed meal of 317 kcal was used as a stimulus. Blood sampling for C-peptide determinations was performed at regular intervals. Although all the studied C-peptide variables were significantly lower in the diabetic group (P < 0.0001), some overlapping of parameters was observed between the two groups. The highest degree of overlapping was found for basal value (BV) (30.8%) and percent increase (42.31%), and the lowest for incremental area, absolute increase, peak value (PV) (3.8%), and total area (7.7%) (chi 2 = 31.6, P < 0.0001). We did not observe a definite pattern in the time of maximum response among the 21 diabetics who showed an increase in C-peptide levels after the stimulus. In this group, however, there was a highly significant number of late responses (120 min) (chi 2 = 5.7, P < 0.002). Although BV showed a significant correlation with PV (rS = 0.95, P < 0.0001), the basal levels of C-peptide did not differentiate the groups with and without response to the stimulus. We conclude that the diabetic group studied showed delayed and reduced C-peptide responses, and that the functional test can be an important tool for the evaluation of residual beta cell function. Topics: Adolescent; Adult; Brazil; C-Peptide; Child; Diabetes Mellitus, Type 1; Eating; Female; Humans; Male | 1997 |
[Contribution of plasma C-peptide to the classification of sugar diabetes in Dakar, Senegal].
When diabetes has been diagnosed, its classification into different types is traditionally carried out according to clinical criteria. But with arising of new parameters, one of which is C-peptide, and various subtypes of diabetes, it became more difficult. So, in order to improve the accuracy of the classification, 270 diabetic patients and 269 controls, all black senegalese subjects, were submitted to a two-step oral glucose tolerance test (0 and 120 min.) with determination of plasma glucose and C-peptide concentrations. The majority of NIDDM were confirmed at the opposite of IDDM; furthermore, it has been pointed out a group corresponding with impaired glucose tolerance (IGT) among the initial controls. When comparing the two classification modes, before and after plasma C-peptide determination, it appeared statistically significant differences with p values of 10(-4) for both IDDM and NIDDM. Topics: Adult; Black People; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Senegal | 1997 |
[Clinical characteristics and main diagnostic points of latent autoimmune diabetes mellitus in adults].
To understand latent autoimmune diabetes mellitus in adults (LADA), we compared the clinical characteristics, fasting plasma glucose and C-peptide level, genetic frequency of HLA-DQA1, -DQB1 chain in 25 patients with LADA, 57 patients with insulin-dependent diabetes mellitus (IDDM, 21 patients with children-onset IDDM, 36 patients with adult-onset IDDM with ketosis), 38 patients with NIDDM (mild and moderate 30 patients and severe 8) and 42 normal persons. The onset of age was 20-48 years old associated with obvious polyphagia, and weight loss. Body mass index (BMI) was < or = 25 and fasting plasma glucose was > or = 16.5 mmol/L (297 mg/dl). Fasting and 1, 2 hour post prandial C-peptide level showed low and flatter curve (0.4, 0.8 and 0.8 nmol/L respectively). Glutamate decarboxylase (GAD) antibody was positive. HLA-DQ beta chain substitution of aspartate molecule was at position 57 (susceptic gene). LADA could be diagnosed if a patient has the first point and any point of the second to the fourth point. Patients with LADA should take diet, exercises, especially insulin as early as possible in order to control fasting and post prandial plasma glucose, and prevent from further destroy of residue islet B cells and reduce diabetic complications of eye, kidney and nerve. Topics: Adult; Antibodies; Autoimmune Diseases; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gene Frequency; Glutamate Decarboxylase; HLA-DQ alpha-Chains; HLA-DQ Antigens; Humans; Ketosis; Male | 1997 |
Hepatic insulin resistance after pancreas transplantation in type I diabetes.
Hyperinsulinemia and peripheral insulin resistance caused by systemic insulin delivery and prednisone therapy are recognized consequences of pancreas transplantation. However, there is little information about insulin action on the liver. To investigate hepatic insulin sensitivity in recipients of pancreas transplants, we devised a staged euglycemic hyperinsulinemic clamp to measure hepatic glucose production (HGP) in 10 type I diabetic pancreas transplant recipients, 10 pair-matched healthy control subjects, and 6 nondiabetic kidney transplant recipients. Clamps were performed in two sequential stages. In stage 1, a 2-h low-dose insulin infusion (0.4 mU.kg-1.min-1) was used to partially suppress HGP. In stage 2, insulin-mediated suppression of HGP was challenged by a 1.5-h glucagon infusion (0.8 ng.kg-1.min-1), while continuing the hyperinsulinemic euglycemic-clamp conditions. During both stages, somatostatin (250 micrograms/h) was infused to suppress endogenous insulin secretion. All subjects underwent stage 1, and all except one pancreas recipient and a respective matched healthy control subject completed stage 2. Fasting HGP was greater in pancreas recipients than in healthy control subjects (15.1 +/- 0.7 vs. 12.0 +/- 0.4 mumol.l-1.kg-1.min-1, P < 0.005) but similar in healthy control subjects and in kidney recipients. During stage 2, both total (706 +/- 28 vs. 469 +/- 31 mumol.l-1.kg-1, P < 0.005) and incremental (62 +/- 20 vs. -21 +/- 16 mumol.l-1.kg-1, P < 0.005) HGP responses to glucagon infusion were significantly greater in pancreas recipients than in healthy control subjects. Changes in HGP in kidney recipients during stage 2 were not significantly different from those in healthy control subjects. In conclusion, fasting HGP is increased in pancreas transplant recipients. Furthermore, recipients have hepatic insulin resistance as demonstrated by an enhanced stimulatory effect of glucagon on HGP during insulin-mediated HGP suppression. Because the magnitude of hepatic insulin resistance was a significant (P < 0.01) predictor of HbA1c level, we suggest that variable hepatic insulin resistance may be responsible for some of the variance observed in glycemic levels after successful pancreas transplantation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin Resistance; Liver; Male; Pancreas Transplantation | 1996 |
Immunological and metabolic effects of prophylactic insulin therapy in the NOD-scid/scid adoptive transfer model of IDDM.
Prophylactic insulin therapy prevents IDDM in spontaneous animal models of the disease and has shown promise in preventing the disease in humans. Although large clinical trials have been formed to use this therapy, a comparative analysis of the efficiency of different pharmaceutical forms and doses of insulin in preventing IDDM has not been performed, and the mechanism underlying the observed prevention of disease is unknown. In the NOD-scid/scid adoptive transfer model of IDDM (10(7) new-onset NOD splenocytes injected intravenously into 6- to 8-week NOD/scid-scid recipients; insulitis develops at 6-9 days post-transfer and 100% IDDM by 32 days post-transfer), life-table (log-rank) analyses revealed that IDDM can be delayed (compared with insulin-free diluent, once daily, n = 8) with equivalent efficiency by prophylactic administration (-9-50 days post-transfer) of high (metabolism-altering) doses of short-acting (0.5 U, once daily, regular, n = 13) or long-acting (0.5 U, once daily, ultralente, n = 9) insulin as well as non-metabolism-altering low-dose insulin (0.02 U, once daily, regular, n = 8). Furthermore, IDDM was delayed with somatostatin (0.2 microgram, twice daily, n = 11), an agent that suppresses endogenous insulin production. No significant difference was seen between the preventative effects of these agents. In an assessment of when therapies can be initiated and still maintain clinical efficiency, only prophylactic somatostatin therapy delayed IDDM (n = 10, P = 0.02) when initiated at 14 days post-transfer, whereas the short-acting insulin regimen did not retard the onset of IDDM (n = 8, P = 0.25) compared with diluent-treated controls. The 24-h urinary C-peptide levels were significantly reduced with short-acting (-56%, P = 0.01) and long-acting (-67%, P = 0.02) insulin products and somatostatin (-59%, P = 0.02) compared with diluent-treated controls. These results indicate that both immunological and metabolic (i.e., beta-cell rest) factors may contribute to the beneficial effects of prophylactic insulin therapy. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Immunization, Passive; Insulin; Mice; Mice, Inbred NOD; Mice, SCID; Somatostatin; Time Factors | 1996 |
Characterization of human DNA topoisomerase II as an autoantigen recognized by patients with IDDM.
Autoantibodies against several cytoplasmic autoantigens such as glutamic acid decarboxylase, heat shock protein 65, insulin, and carboxypeptidase H have been identified in the sera of patients with IDDM. To investigate whether type II DNA topoisomerase (TopII) is an autoantigen in IDDM patients, we have constructed a series of overlapping DNA TopII fragments that covered the entire length of this enzyme. These fragments were used as antigens to screen sera of IDDM patients. We have examined 195 Chinese IDDM patients (mean age 14.2 +/- 7.5 years, age at onset 9.2 +/- 6.4 years, duration of diabetes 4.6 +/- 3.4 years) and 51 nondiabetic individuals. The results showed that DNA TopII autoantibodies were detected in 49.2 and 47.2% of IDDM patients using purified TopII fragments and full-length TopII as antigens, respectively. The frequency of anti-TopII positivity was relatively stable irrespective of sex and disease duration. The patients were slightly older at onset and the prevalence of anti-thyroglobulin/anti-microsomal autoantibodies was twice that in the IDDM subgroup positive for anti-TopII than in IDDM patients who were negative for anti-TopII. We also characterized the epitopes of DNA TopII that were recognized by IDDM sera. Those epitopes resided mostly in three distinct domains. One resided in amino acid residues 1-147, another in amino acid residues 286-472, and the third in the COOH-terminal one-third of DNA TopII. Intriguingly, we found that these epitopes shared similarity (up to 36% identity and 63.6% homology) to previously identified epitopes of IDDM autoantigens. Topics: Adolescent; Adult; Age of Onset; Autoantibodies; Autoantigens; Base Sequence; C-Peptide; Child; Child, Preschool; China; Diabetes Mellitus, Type 1; DNA Primers; DNA Topoisomerases, Type I; Enzyme-Linked Immunosorbent Assay; Glutathione Transferase; Humans; Immunoblotting; Infant; Molecular Sequence Data; Polymerase Chain Reaction; Recombinant Fusion Proteins; Reference Values | 1996 |
Hepatic glucose production is regulated both by direct hepatic and extrahepatic effects of insulin in humans.
The present study examines the effect of the route of insulin delivery on glucose turnover in humans. By using a new noninvasive in vivo method, the acute effect of insulin secreted by the pancreas can be compared with that of insulin delivered by a peripheral vein. Three euglycemic-hyperinsulinemic studies were performed in lean healthy men. In the first study (n = 10), constant portal hyperinsulinemia was produced using a programmed intravenous tolbutamide infusion algorithm, and the insulin secretion rate was mathematically derived by deconvolution from peripheral plasma C-peptide levels. In the second study (n = 10), exogenous insulin was infused by peripheral vein at the same rate as that determined in the first study. In the third study (n = 7), the peripheral insulin levels in the first study were matched by infusing exogenous insulin into a peripheral vein at half that rate. Peripheral insulin levels were higher (P < 0.001) with the full-rate peripheral insulin infusion (266.3 +/- 28.1 pmol/l) than with the portal delivery of insulin (171.1 +/- 30.4 pmol/l) or the half-rate peripheral insulin infusion (158.6 +/- 7.4 pmol/l) (portal versus half-rate peripheral insulin infusion, NS). Calculated hepatic insulin levels were higher (P < 0.001) in the portal insulin study (443.1 +/- 52.6 pmol/l) than in the full-rate peripheral insulin study (303.6 +/- 30.9 pmol/l) or in the half-rate peripheral insulin study (204.5 +/- 9.8 pmol/l). Hepatic glucose production (HGP) was suppressed to a greater extent with the full-rate peripheral insulin infusion (69.3 +/- 7.8%, P < 0.001 vs. portal or half-rate peripheral insulin) than portal (50.3 +/- 9.8%) or half-rate peripheral insulin infusion (36.8 +/- 3.8%). In the portal insulin study, however, suppression was greater than in the half-rate peripheral insulin study (P < 0.01), in spite of equal peripheral insulin levels. The assumption that tolbutamide, when used in this fashion, has no independent effect on glucose turnover, glucagon, or gluconeogenic precursor and energy substrates for gluconeogenesis was validated in five C-peptide-negative patients with IDDM. We conclude that in nondiabetic humans, 1) peripheral effects of insulin are important in suppressing HGP, as evidenced by the greater suppression of HGP with equivalent rate peripheral versus portal insulin delivery, and 2) because HGP was suppressed to a greater extent with portal verus peripheral insulin delivery at half the rate when peripheral insul Topics: Adult; Algorithms; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Gluconeogenesis; Glucose Clamp Technique; Homeostasis; Humans; Hypoglycemic Agents; Infusions, Intravenous; Insulin; Insulin Secretion; Kinetics; Liver; Male; Portal System; Reference Values; Tolbutamide | 1996 |
LDL from patients with well-controlled IDDM is not more susceptible to in vitro oxidation.
Increased susceptibility of LDL to oxidation has been shown to be associated with the presence of coronary heart disease and may account for the accelerated vascular disease seen in diabetes. The response of LDL to in vitro oxidative stress has been proposed as a measure of the predisposition of LDL to the in vivo subendothelial oxidative stress. Increased susceptibility to oxidation has been demonstrated recently in diabetic patients with poorly controlled IDDM. Thus, we conducted studies to determine whether the increased susceptibility of LDL to oxidation was secondary to diabetes per se or to the level of glycemic control. Fifteen IDDM patients with good glycemic control and with no evidence of macrovascular disease or proteinuria were compared with healthy age-, sex-, race-, and BMI-matched nondiabetic subjects. Fasting blood glucose levels averaged 12.1 +/- 1.1 (mean +/- SE) vs. 4.9 +/- 0.1 mmol/l in the diabetic versus the control groups, respectively. HbA1c levels averaged 7.7 +/- 0.5 vs. 4.4 +/- 0.2%, reflecting well-controlled diabetes (P < 0.0001). Total, LDL, VLDL, and HDL cholesterol, triglyceride, and lipoprotein(a) levels did not differ between the groups. The particle size, lipid composition, fatty acid content, antioxidant content, and glycation were similar for LDL isolated from both groups. A rapid LDL preparation technique was used to compare LDL susceptibility to oxidation under the following conditions: final LDL cholesterol concentration of 100 microg/ml, 5 micromol/l of CuCl2 at 25 degrees C. There was no difference in the susceptibility to in vitro oxidation of LDL isolated from IDDM patients compared with control subjects. There was no correlation of glycemic control with any of the parameters of the in vitro oxidation of LDL. LDL from patients with well-controlled IDDM does not differ in composition or in susceptibility to in vitro oxidative stress compared with LDL from nondiabetic subjects. Topics: Adult; Antioxidants; Blood Glucose; Blood Specimen Collection; Body Mass Index; C-Peptide; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Cholesterol, VLDL; Diabetes Mellitus, Type 1; Fatty Acids; Female; Humans; Lipoproteins, LDL; Male; Oxidation-Reduction; Phospholipids; Reference Values; Triglycerides; Vitamins | 1996 |
Antibodies to glutamic acid decarboxylase and insulin-dependent diabetes in patients with autoimmune polyendocrine syndrome type I.
To evaluate the association of autoimmunity to glutamic acid decarboxylase (GAD) with insulin-dependent diabetes mellitus (IDDM) and IDDM-associated human leukocyte antigen (HLA) types, we studied a unique group of 47 patients with autoimmune polyendocrine syndrome type 1, a recessive disease not associated with HLA. GAD65 antibodies (GAD65-Ab), GAD67-Ab, islet cell antibodies, and HLA-DQA1, -DQB1, and -DRB1 were analyzed in relation to IDDM or a decreased insulin secretory capacity. GAD65-Ab were found in six of the eight diabetic patients 0.9-8.0 yr before the onset of IDDM and in 16 (41%) nondiabetic patients during a follow-up of 2.4-19.5 yr. Eleven (28%) nondiabetic patients had GAD67-Ab and islet cell antibodies. Fasting C peptide (mean +/- SD, 0.5 +/- 0.24 vs. 1.03 +/- 0.49 nmol/L; P = 0.003) and first phase insulin response (75.6 +/- 37.9 vs. 166.4 +/- 112.7 mU/L; P = 0.019) were lower in patients with than in those without GAD65-Ab. No HLA genotype predominated in the IDDM patients or GAD65-Ab-positive nondiabetic patients, but the IDDM high risk genotypes were decreased in frequency among the patients with GAD65-Ab. In conclusion, nondiabetic autoimmune polyendocrine syndrome type 1 patients frequently have GAD65-Ab together with a decreased insulin secretory capacity, suggesting subclinical islet cell inflammation not invariably progressing to diabetes. This is not associated with HLA haplotypes conferring susceptibility to or protection from IDDM. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Genes, MHC Class II; Genotype; Glutamate Decarboxylase; Histocompatibility Testing; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Infant; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Polyendocrinopathies, Autoimmune; Polymerase Chain Reaction | 1996 |
Metabolic effects of successful intraportal islet transplantation in insulin-dependent diabetes mellitus.
The intraportal injection of human pancreatic islets has been indicated as a possible alternative to the pancreas transplant in insulin-dependent diabetic patients. Aim of the present work was to study the effect of intraportal injection of purified human islets on: (a) the basal hepatic glucose production; (b) the whole body glucose homeostasis and insulin action; and (c) the regulation of insulin secretion in insulin-dependent diabetes mellitus patients bearing a kidney transplant. 15 recipients of purified islets from cadaver donors (intraportal injection) were studied by means of the infusion of labeled glucose to quantify the hepatic glucose production. Islet transplanted patients were subdivided in two groups based on graft function and underwent: (a) a 120-min euglycemic insulin infusion (1 mU/kg/min) to assess insulin action; (b) a 120-min glucose infusion (+75 mg/di) to study the pattern of insulin secretion. Seven patients with chronic uveitis on the same immunosuppressive therapy as grafted patients, twelve healthy volunteers, and seven insulin-dependent diabetic patients with combined pancreas and kidney transplantation were also studied as control groups. Islet transplanted patients have: (a) a higher basal hepatic glucose production (HGP: 5.1 +/- 1.4 mg/kg/ min; P < 0.05 with respect to all other groups) if without graft function, and a normal HGP (2.4 +/- 0.2 mg/kg/min) with a functioning graft; (b) a defective tissue glucose disposal (3.9 +/- 0.5 mg/kg/min in patients without islet function and 5.3 +/- 0.4 mg/kg/min in patients with islet function) with respect to normals (P < 0.01 for both comparisons); (c) a blunted first phase insulin peak and a similar second phase secretion with respect to controls. In conclusion, in spite of the persistence of an abnormal pattern of insulin secretion, successful intraportal islet graft normalizes the basal HGP and improves total tissue glucose disposal in insulin-dependent diabetes mellitus. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucagon; Glucose; Glucose Clamp Technique; Homeostasis; Humans; Infusions, Intravenous; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Liver; Liver Transplantation; Male; Middle Aged; Uveitis | 1996 |
Clinical determinants of glucose homeostasis after pancreas transplantation.
Although successful simultaneous pancreas and kidney transplantation (SPK) achieves normoglycemia in the majority of diabetic recipients with end-stage renal disease, little is known about the factors that influence long-term endocrine function. In this prospective study of 48 bladder-drained SPK patients, 209 oral glucose tolerance tests were performed between 3 months and 6 years after transplantation. Normal fasting glucose levels and systemic hyperinsulinemia were stable for up to 6 years after SPK. Multivariate analysis revealed that increased area-under-curve (AUC) levels of C-peptide 3 months after transplantation were predicted by short surgical pancreas anastomosis time, greater recipient body weight, and total HLA mismatch score. Episodes of acute pancreas rejection were not associated with reduced allograft insulin output in the long term. Insulin output, stimulated by oral glucose tolerance tests and assessed by the ratio of AUC insulin to AUC glucose, fell gradually after transplantation and was decreased by an elevated serum calcium level and high cyclosporine dose. The ratio of fasting insulin to glucose, which acts as a marker of peripheral insulin resistance, fell with time after transplantation and was increased by greater body weight, higher prednisolone dose, and lower cyclosporine dose. The inhibitory effect of cyclosporine on both fasting and postprandial insulin output was, however, minor when quantified by multivariate analysis. Endocrine function of the transplanted pancreas was not correlated with its exocrine function measured by urinary amylase excretion, nor was there a correlation with change in renal function measured by isotopic glomerular filtration rate. In summary, simultaneous pancreas and kidney transplantation leads to excellent long-term glucose homeostasis maintained at the expense of systemic hyperinsulinemia. The key factors adversely affecting peripheral resistance in SPK were corticosteroid therapy, body weight, and time after transplantation. The susceptibility of islets to ischemia-reperfusion injury, as quantitated by surgical anastomosis time, may have implications for islet transplantation programs, as may the relative resistance of islets to allograft rejection. Glucose homeostasis after SPK, while remaining abnormal, may be used as the standard against which islet transplantation must be measured. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glomerular Filtration Rate; Glucose; Glucose Tolerance Test; Homeostasis; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Kidney Failure, Chronic; Kidney Transplantation; Liver; Liver Glycogen; Longitudinal Studies; Middle Aged; Multivariate Analysis; Pancreas Transplantation; Prospective Studies; Time Factors | 1996 |
Proinsulin immunoreactivity in recent-onset IDDM: the significance of insulin antibodies and insulin autoantibodies.
To study the natural history of fasting proinsulin immunoreactivity (PIM) during the first 30 months of IDDM and its relationship to fasting C-peptide and insulin antibodies.. An incidence cohort of 204 consecutive newly diagnosed IDDM patients were followed prospectively, having blood drawn for measurements at diagnosis and at 1, 3, 6, 9, 12, 18, 24, and 30 months. A sensitive enzyme-linked immunosorbent assay was used for the determination of PIM.. All patients had detectable fasting PIM in plasma at diagnosis, with a median value and interquartile range of 3.5 pmol/l (2.2-6.2). The median PIM level increased during the first months of IDDM to reach a peak at 9-12 months (9.9-10.3 pmol/l). PIM then declined gradually to 5.6 pmol/l (1.9-13.5) at 30 months without reaching baseline. PIM at each time point was widely scattered in a skewed log-normal distribution without signs of bimodality. After the onset of insulin treatment, median insulin antibody level increased and declined in a similar pattern. Both PIM and antibody level were significantly higher in children and adolescents compared with adults. However, stepwise multiple regression analysis showed that age was only of minor importance for the PIM variation during the study period. Insulin antibody level and fasting C-peptide were the major determinants at 3-30 months, accounting for approximately 40% of the variation (R2). Blood glucose was of minor importance, and insulin dose, HbA1c, and BMI were of no importance. The correlation between fasting PIM and fasting C-peptide improved (R2 doubled) if the insulin antibody level was accounted for. Further, the slope of the correlation curve between PIM and C-peptide increased threefold when antibody binding was > 4%. At diagnosis, insulin autoantibodies could be detected in 19% of the patients. Their presence predicted higher proinsulin at 1-3 months, a higher insulin dose the 1st year, and higher levels of insulin antibodies later in the study.. Circulating insulin antibodies may affect the level of PIM in IDDM, probably by adding a pool of IgG-bound PIM thereby increasing half-life and plasma concentration. This may explain why C-peptide and PIM levels do not change in concert during the 1st years of IDDM. Unlike C-peptide, PIM can not therefore quantitate beta-cell secretion unless the presence of insulin antibodies is ruled out. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin Antibodies; Male; Proinsulin; Regression Analysis; Sex Characteristics; Sex Factors; Time Factors | 1996 |
Relationship between GAD antibody and residual beta-cell function in children after overt onset of IDDM.
Topics: Adolescent; Age of Onset; Autoantibodies; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glutamate Decarboxylase; Humans; Islets of Langerhans; Male; Reproducibility of Results; Time Factors | 1996 |
C-peptide stimulates glucose transport in isolated human skeletal muscle independent of insulin receptor and tyrosine kinase activation.
We have previously demonstrated that C-peptide stimulates glucose transport in skeletal muscle from non-diabetic subjects in a dose-dependent manner. To further elucidate the mechanism by which C-peptide activates glucose transport, we investigated the influence of human recombinant C-peptide on receptor and post-receptor events involved in the glucose transport process. Human skeletal muscle specimens were obtained from the vastus lateralis by means of an open biopsy procedure. Stimulation of isolated muscle strips from healthy control subjects with supra-physiological concentrations of insulin (6,000 pmol/l) and C-peptide (2,500 pmol/l), did not further augment the twofold increase in the rate of 3-o-methylglucose transport induced by either stimulus alone. C-peptide did not displace 125I-insulin binding from partially purified receptors, nor did it activate receptor tyrosine kinase activity. Tyrosine-labelled 125I-C-peptide did not bind specifically to crude membranes prepared from skeletal muscle, or to any serum protein other than albumin. The beta-adrenergic receptor stimulation with isoproterenol inhibited insulin- but not C-peptide-mediated 3-o-methylglucose transport by 63 +/- 18% (p < 0.01), whereas the cyclic AMP analogue, Bt2cAMP, abolished the insulin- and C-peptide-stimulated 3-o-methylglucose transport. C-peptide (600 pmol/l) increased 3-o-methylglucose transport 1.8 +/- 0.2-fold in skeletal muscle specimens from patients with insulin-dependent diabetes mellitus. In conclusion, C-peptide stimulates glucose transport by a mechanism independent of insulin receptor and tyrosine kinase activation. In contrast to the effect on insulin-stimulated glucose transport, catecholamines do not appear to have a counter regulatory action on C-peptide-mediated glucose transport. Topics: 3-O-Methylglucose; Adrenergic beta-Agonists; Adult; Biological Transport; Biopsy; Bucladesine; C-Peptide; Diabetes Mellitus, Type 1; Enzyme Activation; Glucose; Humans; In Vitro Techniques; Insulin; Isoproterenol; Kinetics; Male; Methylglucosides; Muscle, Skeletal; Receptor, Insulin; Recombinant Proteins | 1996 |
GAD antibodies in IDDM in Thailand.
Topics: Adult; Age of Onset; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glutamate Decarboxylase; Humans; Incidence; Male; Thailand | 1996 |
Antiphospholipid antibodies and pregnancy disorders in women with insulin dependent diabetes.
Insulin dependent diabetes (IDD) is considered to be an immune endocrinopathy as in such patients a disorder of the immune system is involved; however, up to now no data are available on the occurrence of antiphospholipid antibodies (aPL) in IDD pregnant women and on possible correlation between the presence of aPL and the high fetomaternal morbidity reported in these patients. The presence of lupus anticoagulant (LA) and of anticardiolipin antibodies (ACA) was monthly evaluated. In 35 IDD pregnant women referring within the 7 degrees week of pregnancy to the High Risk Pregnancy Medical Unit. Levels of D-dimer, fibrin degradation product, were also assayed. Twelve IDD pregnant women resulted to be aPL positive with a markedly high prevalence of positivity (34%). aPL positive did not significantly differ from aPL negative women in age, duration and severity of diabetes and in metabolic control throughout pregnancy. Pregnancy induced hypertension (PIH) and intrauterin growth retard (IUGR) were observed in 6/12 aPL positive and in only 2/23 aPL negative patients (p < 0.02). A pathological increase in D-dimer levels occurred in 6/12 aPL positive patients and in none aPL negative (p < 0.03). The high frequency of aPL positivity and its strict relation to pregnancy complications strongly support a major role for an autoimmune pathogenetic mechanism in the occurrence of feto-maternal morbidity in IDD pregnant women. The identification of this subgroup at risk for complications may be clinically relevant. Topics: Analysis of Variance; Antibodies, Anticardiolipin; Antibodies, Antiphospholipid; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin Antibodies; Lupus Coagulation Inhibitor; Maternal-Fetal Exchange; Pregnancy; Pregnancy in Diabetics; Pregnancy Outcome; Pregnancy, High-Risk | 1996 |
Continued insulin dependence despite normal range insulin sensitivity and insulin connecting peptide levels in a kidney/islet transplant patient.
The majority of islet transplant recipients remain insulin-requiring, although many have near-normal connecting peptide (CP) levels. Insulin resistance may be one possible cause of the continuing need for exogenous insulin in islet transplant recipients. To assess this, we have studied the insulin sensitivity index (S1) in one patient with near-normal CP levels after islet transplant who remained insulin-requiring.. The islet transplant recipient is a 36-year-old woman with no residual CP who received a kidney transplant, followed 7 days later by an islet transplant. The islets were infused into the liver via the umbilical vein. Induction immunosuppression consisted of OKT3, prednisone, cyclosporin A, and azathioprine, with maintenance on the latter three.. Maximum CP levels after a standardized Sustacal meal were 2.09, 1.18, 0.85, and 0.81 nmol/l at 1,6,18, and 24 months posttransplant, respectively. Insulin requirements at the same times were 0.27, 0.45, 0.49, and 0.62 U.kg(-1).d(-1), while S1 was 36.3, 53.3, and 13.2 min (-1).nmol(-1).ml at 6,18, and 24 months, respectively. This compares with S1 values of 43.3+/- 10.0 min (-1).nmol(-1).ml for normal subjects.. This patient had near-normal S1 and CP levels, but she was unable to discontinue insulin therapy, suggesting that other factors are critical. Despite this, she maintained normal or near-normal glycated hemoglobins, indicating metabolic benefit from the islet transplant. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Humans; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation | 1996 |
Growth hormone-binding protein related immunoreactivity is regulated by the degree of insulinopenia in diabetes mellitus.
Derangements in the GH/IGF axis are common in patients with diabetes mellitus. In insulin-dependent diabetes mellitus (IDDM), these disturbances seem to be due to a partial defect in GH action on its own receptor or via a post-receptor defect. In non-insulin-dependent diabetes mellitus (NIDDM), data are limited, and the regulation of the GH receptor (GHR) remains unclear. However, animal studies with diabetic rats demonstrated that the GHR density may be influenced by insulin disposal at the hepatocyte. With respect to this hypothesis we studied the relation between peripheral insulin status and the serum GH-binding protein (GHBP), which reflects indirectly the GHR density in the tissues. Patients with IDDM were compared to a NIDDM group as well as to a group of healthy subjects.. Basal blood samples for the determination of serum GHBP, GH, and IGF-I were obtained from patients with IDDM (n = 27), subjects with NIDDM (n = 112) and healthy controle (n = 42). Insulin, proinsulin, C-peptide and IGF-binding protein 1 (IGFBP-1) serum levels were used to estimate the insulin status in diabetic patients.. GHBP serum levels were significantly lower in patients with IDDM than in either NIDDM or controls (P < 0.001). Conversely, the IGF-I levels were reduced in both groups of diabetics. A subgroup of hypoinsulinaemic NIDDM patients showed significantly decreased GHBP concentrations (P < 0.05) compared to the NIDDM sub-group with hyperinsulinaemia. Furthermore, GHBP levels were significantly decreased in insulin-treated patients with NIDDM compared to either non-insulin-requiring subjects or normal controls (P < 0.05). A significant direct relation was found between levels of GHBP and total insulin dose (P < 0.01) in patients with IDDM. In the NIDDM group, GHBP was correlated with proinsulin (P < 0.001), C-peptide (P < 0.01), Insulin (P < 0.05) and inversely with IGFBP-1 (P < 0.001). Multiple linear regression analysis indicated a significant contribution of proinsulin and IGFBP-1 to the variation of GHBP.. Decreased GHBP levels in IDDM as well as in NIDDM correlate with insulinopenia. Since the degree of insulinopenia depends on the capability of the beta-cells to secrete proinsulin, C-peptide and insulin, we hypothesize that these hormones at least partially influence the serum level of GHBP. Low GHBP levels may reflect a reduced GH receptor density and a concomitant GH insensitivity, which leads to an impaired IGF generation in insulin-deficient patients. Topics: Adult; Aged; C-Peptide; Carrier Proteins; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Growth Hormone; Humans; Insulin; Insulin-Like Growth Factor Binding Protein 1; Insulin-Like Growth Factor I; Male; Middle Aged; Proinsulin; Receptors, Somatotropin | 1996 |
Clinical islet transplantation: a consortium model.
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Humans; Immunosuppression Therapy; Kidney Failure, Chronic; Kidney Transplantation; Liver Failure; Liver Transplantation; Middle Aged; Pancreas Transplantation; Patient Selection; Retrospective Studies; Transplantation, Autologous; Transplantation, Homologous | 1996 |
Increased lipid oxidation but normal muscle glycogen response to epinephrine in humans with IDDM.
The effects of physiological increments in epinephrine and insulin on glucose production (GP), skeletal muscle glycogen metabolism, and substrate oxidation were studied in eight insulin-dependent diabetes mellitus (IDDM) and nine control subjects. Epinephrine was coinfused for the final 120 min of a 240-min euglycemic, hyperinsulinemic clamp. In both groups, insulin increased glucose uptake, glycogen synthesis, and whole body carbohydrate (CHO) oxidation and inhibited GP (by 70-80%) and lipid oxidation (by approximately 50%), whereas epinephrine antagonized the effect of insulin on glucose uptake and glycogen synthesis. In contrast, GP increased in IDDM subjects (P < 0.02) but remained suppressed by insulin in controls. CHO oxidation fell (1.37 +/- 0.25 vs. 2.08 +/- 0.32 mg.kg-1.min-1) and lipid oxidation increased to baseline in IDDM subjects, with increments in plasma free fatty acids (FFA) and glycerol. In contrast, in controls, plasma FFA and glycerol remained suppressed and lipid oxidation decreased further with epinephrine (P < 0.005). Epinephrine completely reversed insulin's activation of muscle glycogen synthase in both groups. Thus, during hyperinsulinemia, the hepatic response to epinephrine in IDDM subjects may be dependent on activation of lipid oxidation. Skeletal muscle glycogen metabolism is exquisitely sensitive to epinephrine despite the presence of hyperinsulinemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glycogen; Glycogen Synthase; Hormones; Humans; Insulin; Lipid Metabolism; Male; Middle Aged; Muscle, Skeletal; Oxidation-Reduction; Phosphorylases; Reference Values | 1996 |
Determinants of a normal (versus impaired) oral glucose tolerance after combined pancreas-kidney transplantation in IDDM patients.
After successful pancreas transplantation, insulin-dependent diabetic patients are characterized by a normal or at worst impaired oral glucose tolerance (World Health Organisation criteria). It is not known which pathophysiological mechanisms cause the difference between normal and impaired oral glucose tolerance. Therefore, we studied 41 patients after successful combined pancreas-kidney transplantation using stimulation in the fasting state with oral glucose (75 g), intravenous glucose (0.33 g/kg) and glucagon bolus injection (1 mg i.v.). Glucose (glucose oxidase), insulin and C-peptide (immunoassay) were measured. Repeated-measures analysis of variance and multiple regression analysis were used to analyse the results which showed: 28 patients had a normal, and 13 patients had an impaired oral glucose tolerance. Impaired oral glucose tolerance was associated with a greatly reduced early phase insulin secretory response (insulin p < 0.0001; C-peptide p = 0.037). Age (p = 0.65), body mass index (p = 0.94), immunosuppressive therapy (cyclosporin A p = 0.84; predniso(lo)ne p = 0.91; azathioprine p = 0.60) and additional clinical parameters were not different. Reduced insulin secretory responses in patients with impaired oral glucose tolerance were also found with intravenous glucose or glucagon stimulations. Exocrine secretion (alpha-amylase in 24-h urine collections) also demonstrated reduced pancreatic function in these patients (-46%; p = 0.04). Multiple regression analysis showed a significant correlation of 120-min glucose with ischaemia time (p = 0.003) and the number of HLA-DR mismatches (p = 0.026), but not with HLA-AB-mismatches (p = 0.084). In conclusion, the pathophysiological basis of impaired oral glucose tolerance after pancreas transplantation is a reduced insulin secretory capacity. Transplant damage is most likely caused by perioperative influences (ischaemia) and by the extent of rejection damage related, for example, to DR-mis-matches. Topics: Adult; alpha-Amylases; Analysis of Variance; Biomarkers; Blood Glucose; Blood Group Incompatibility; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Glucagon; Glucose Intolerance; Glucose Tolerance Test; Graft Rejection; Graft Survival; Histocompatibility Testing; Humans; Immunosuppressive Agents; Insulin; Insulin Secretion; Kidney Transplantation; Male; Pancreas Transplantation; Reference Values; Regression Analysis; Time Factors | 1996 |
Pancreatic beta cell function and antibodies to glutamic acid decarboxylase (anti-GAD) in Chinese patients with clinical diagnosis of insulin-dependent diabetes mellitus.
Antibodies to glutamic acid decarboxylase (anti-GAD) and pancreatic beta cell secretory function were measured in 39 consecutive Chinese patients with a clinical diagnosis of insulin-dependent diabetes mellitus (IDDM) (19 males, mean +/- SD age. 37 +/- 15 years; body mass index (BMI), 22 +/- 4 kg/m2; mean duration of disease, 6.7 +/- 5.6 years). IDDM was defined on the basis of acute symptoms with heavy ketonuria (> 3+) or ketoacidosis at diagnosis, or requirement for continuous insulin treatment within one year of diagnosis. Insulin deficiency was defined as a post-glucagon stimulated plasma C-peptide concentration < or = 0.6 nmol/l. Overall, anti-GAD antibodies were positive (> 18 units) in 23% (n = 9) of these patients. Of the 39 patients, 29 (74%) were insulin deficient and 10 (26%) were non-insulin deficient. Anti-GAD antibodies were positive in 31% of the insulin-deficient patients but in none of the non-insulin-deficient group. Insulin deficiency and anti-GAD positivity were associated with younger age, earlier age of clinical onset and lower BMI. There were independent negative relationships between levels of anti-GAD antibodies and blood pressure and a positive relationship between insulin dosage and albuminuria. This study emphasises the difficulty in differentiating clinically between IDDM and NIDDM in Chinese patients. Despite the acute presentation, these patients had variable pancreatic beta cell secretory function. The varying duration of disease may partly explain the low prevalence of positive anti-GAD antibodies in these patients, but seems unlikely to explain fully the difference from Caucasian IDDM patients. Topics: Adult; Australia; Autoantibodies; Blood Glucose; Blood Pressure; Body Mass Index; C-Peptide; China; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glutamate Decarboxylase; Glycated Hemoglobin; Hong Kong; Humans; Insulin; Islets of Langerhans; Male; Regression Analysis | 1996 |
Clinical significance and time course of antibodies to glutamic acid decarboxylase in Japanese children with type I (insulin-dependent) diabetes mellitus.
Although anti-glutamic acid decarboxylase antibodies (GADAb) have been reported to be a useful diagnostic and predictive marker of insulin-dependent diabetes mellitus (IDDM, type 1 DM) in Caucasians, a precise analysis of GADAb in Japanese children has not been reported. We examined the clinical significance and time course of GADAb in Japanese IDDM children, who have different genetic backgrounds from Caucasians. Twenty-three of 34 (67.6%) sera from recent-onset (< 6 months) IDDM, and 16 of 49 (32.7%) sera from long-standing (> or = 2 years) IDDM patients were positive for GADAb. This prevalence of GADAb in IDDM patients was significantly higher than in normal controls and the other groups including non-insulin-dependent DM, autoimmune thyroid disease and congenital hypothyroidism, and was also significantly higher in recent-onset than in long-standing IDDM. Time course analysis suggested that autoimmune response against GAD could follow different courses in individual cases after the initiation of insulin therapy. The incidence of GADAb was significantly higher in females than in males in the older age group (11-15 years). Other clinical features including residual pancreatic beta-cell function after diagnosis were demonstrated to be similar between GADAb-positive and -negative patients. In conclusion, this study using the newly established radioimmunoassay (RIA) for GADAb revealed a high prevalence of autoimmune reactivity to GAD in Japanese IDDM children. These results, using this RIA procedure, might assist in laying the groundwork for future trials of immunomodulation therapy for IDDM in Japan. Topics: Adolescent; Age Factors; Antibodies; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Humans; Islets of Langerhans; Japan; Male; Radioimmunoassay; Sex Factors; Time Factors | 1996 |
Renal metabolism of C-peptide in patients with early insulin-dependent diabetes mellitus.
Renal metabolism of C-peptide was studied in 6 patients with early insulin-dependent diabetes mellitus (IDDM) with residual beta cell activity and in 11 nondiabetic subjects by the arterial-venous difference technique both in the postabsorptive state and for 80 min after ingestion of an amino acid mixture (0.8 g/kg). Urinary C-peptide (Cp) excretion, glomerular filtration rate and renal plasma flow were also measured. In the postabsorptive state in IDDM, renal uptake of Cp is reduced, while its urinary excretion and clearance are significantly increased. As a result, net renal extraction is markedly reduced. In contrast to controls, renal uptake and net extraction of C-peptide after amino acid ingestion do not increase in patients; the peritubular uptake evident in normal subjects is not detectable. Urinary excretion and clearance of Cp remain significantly higher in IDDM patients. In both groups, renal uptake of C-peptide is directly related to its renal load: however, in IDDM, the increase in Cp uptake for each increment in renal load is 35% lower than in controls (p < 0.001). Furthermore, as opposed to controls, urinary Cp excretion is not correlated with its arterial levels. Therefore IDDM patients have marked defects in renal handling of endogenous Cp, regarding both the amount metabolized by renal tissue and that reabsorbed by tubular cells. These data indicate an early alteration in the diabetic kidney that also impairs the reliability of urinary Cp evaluation as an index of residual beta cell activity in IDDM patients. Topics: Adult; Amino Acids; Basal Metabolism; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Kidney; Male; Time Factors | 1996 |
Normalization of insulin sensitivity and glucose homeostasis in type I diabetic pancreas transplant recipients: a 48-month cross-sectional study--a clinical research center study.
Despite the establishment of heterotopic, whole cadaveric, pancreas-kidney transplantation as an effective form of therapy for type I diabetes with chronic renal insufficiency, uncertainty remains regarding the potentially deleterious effects of severe peripheral hyperinsulinemia and long-term immunosuppressive therapy on insulin sensitivity (SI) and, subsequently, on beta-cell function and maintenance of euglycemia over years. To examine the alterations in SI that may occur over time and their impact on glucose homeostasis, beta-cell function, SI, and glucose effectiveness (SG) were measured using the frequently sampled iv glucose tolerance test (FSIGTT) and minimal model method in 39 glucose-tolerant type I diabetic pancreas-kidney transplant recipients in a cross-sectional manner at 3, 6, 12, 24, 36, and 48 months post transplantation. Mean basal and poststimulation (oral glucose tolerance test and FSIGTT) serum glucose responses were similar among the groups from 3-48 months. Plasma insulin response during the FSIGTT was higher (P < 0.001, repeated measures ANOVA) at 6 months vs. 12-48 months. Incremental integrated areas under the curve for 1st phase, glucose-stimulated, tolbutamide-stimulated, and total insulin responses tended to be higher (P = NS) at 6 months. Glucose disappearance rate constant, kG, did not differ significantly from 3-48 months. Mean +/- SE S1 in the pancreas-kidney recipients was 4.25 +/- 1.6 x 10(-4) min-1/microU.mL-1 at 3 months (group 1, n = 7) (vs. 7.9 +/- 0.9 x 10(-4) normal reference), decreased to 2.95 +/- 0.6 at 6 months (group 2, n = 11), improved to baseline values of 4.6 +/- 1.0 at 12 months (group 3, n = 10), and normalized at 24 months (group 4, n = 6) to 7.5 +/- 1.7 (P = 0.008). The normalisation in SI was sustained at 36 months (group 5, n = 3, 8.0 +/- 3.7, P = 0.03), and up to 48 months (group 6, n = 5, 6.1 +/- 1.6, P = 0.04) in the type I diabetic pancrease allograft recipients. Corresponding SG tended to increase but did not differ significantly from 3 (1.69 +/- 0.2 x 10(-2)/min), 6 (2.33 +/- 0.39), 12 (1.9 +/- 0.2), 24 (1.9 +/- 0.4), 36 (1.98 +/- 0.15), and 48 months (2.27 +/- 0.3). Hepatic insulin extraction did not differ among the groups. SI correlated significantly with prednisone dose (r = -0.45, P = 0.002). In summary, after successful whole cadaveric, heterotopic, pancreas-kidney transplantation in type I diabetic recipients: 1) euglycemia remains relatively stable over 48 months; 2) SI is diminished ea Topics: Adult; Blood Glucose; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Food; Glucose Tolerance Test; Homeostasis; Humans; Hypoglycemic Agents; Insulin; Kidney Transplantation; Kinetics; Male; Pancreas Transplantation; Tolbutamide | 1996 |
Effects of the short-acting insulin analog [Lys(B28),Pro(B29)] on postprandial blood glucose control in IDDM.
To establish the effects of the short-acting insulin analog Lispro versus human regular insulin (Hum-R) on postprandial metabolic control in IDDM.. Four studies were performed in 10 C-peptide-negative IDDM patients. Lispro or Hum-R (0.15 U/kg) or Lispro + NPH (0.07 U/kg) or Hum-R + NPH were injected subcutaneously 30 min (Hum-R) or 5 min (Lispro) before lunch. Preprandial plasma glucose (PG) was maintained on all four occasions at approximately 7.3 mmol/l by intravenous insulin.. After subcutaneous Lispro injection, plasma free insulin (FIRI) was greater between 0 and 2 h (233 +/- 22 pmol/l) than after Hum-R (197 +/- 25 pmol/l) but lower between 2.25 and 7 h (81 +/- 10 vs. 104 +/- 13 pmol/l, P < 0.05). After Lispro, PG was lower versus Hum-R for 3 h (7.4 +/- 0.6 vs. 8.3 +/- 0.9 mmol/l) but subsequently increased more than after Hum-R (3.25-7h, 11.3 +/- 1 vs. 9.6 +/- 1.2 mmol/l), resulting in a 7-h postprandial PG greater than Hum-R (9.4 +/- 0.5 vs. 8.8 +/- 0.6 mmol/l) (all P < 0.05). Addition of NPH to Lispro increased the 2.5-to 7-h FIRI to 110 +/- 11 pmol/l and decreased the 3.25- to 7-h PG to 7.7 +/- 0.8 pmol/l, resulting in 0- to 7-h PG (7.3 +/- 0.3 mmol/l) lower than after Hum-R + NPH (7.9 +/- 0.5 pmol/l) (P < 0.05).. At meals, in order for Lispro to improve postprandial blood glucose not only at 2-h, but also over a 7-h period in C-peptide-negative IDDM, basal insulin must be optimally replaced. Topics: 3-Hydroxybutyric Acid; Adult; Alanine; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glycerol; Humans; Hydroxybutyrates; Infusions, Intravenous; Insulin; Insulin Lispro; Insulin, Isophane; Lactates; Male; Postprandial Period; Recombinant Proteins | 1996 |
Sex hormones and DHEA-SO4 in relation to ischemic heart disease mortality in diabetic subjects. The Wisconsin Epidemiologic Study of Diabetic Retinopathy.
Sex hormones are associated with atherogenic changes in lipoproteins and changes in glucose and insulin metabolism, yet few data are available on the relationship of sex hormones and dehydroepiandrosterone sulfate (DHEA-SO4) to ischemic heart disease (IHD) in diabetic subjects, a group with very high levels of IHD.. We examined the relation of total and free testosterone, sex hormone binding globulin, estrone, estradiol, and DHEA-SO4 to the 5-year IHD mortality in the older-onset diabetic subjects in the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) in a matched diabetic subject-control design (two control subjects for every diabetic subject).. In men (n = 123), none of the sex hormones or DHEA-SO4 significantly predicted IHD mortality. In women (n = 120), lower levels of DHEA-SO4 (P < 0.01) and total testosterone (P = 0.07) predicted IHD mortality. These results were essentially unchanged after adjustment for duration of diabetes, GHb, diuretic use, and serum creatinine, which are major predictors of IHD mortality in the WESDR. Finding lower testosterone levels in diabetic subjects of IHD in women is contrary to data on risk factors, which suggests that increased androgen activity may be associated with worse IHD risk factors.. This study suggests that alterations in sex hormones and DHEA-SO4 are unlikely to explain a major proportion of the variation in IHD mortality in diabetic subjects. Topics: Adult; Age of Onset; Aged; Biomarkers; C-Peptide; Cross-Sectional Studies; Dehydroepiandrosterone Sulfate; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Retinopathy; Estradiol; Estrone; Female; Humans; Hypertension; Male; Middle Aged; Myocardial Ischemia; Predictive Value of Tests; Proteinuria; Sex Characteristics; Sex Hormone-Binding Globulin; Smoking; Testosterone; Wisconsin | 1996 |
Erythrocyte and plasma antioxidant activity and subclinical complications in young diabetic patients.
Topics: Adolescent; Antioxidants; Ascorbic Acid; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Erythrocytes; Humans; Insulin; Insulin Secretion; Vitamin E | 1996 |
Pharmacokinetics of transperitoneal insulin transport.
Seven type I insulin-dependent diabetic patients on continuous ambulatory peritoneal dialysis treatment were selected for this study. Each patient participated in three different 6-hour 'single-dwell' studies on 3 consecutive days. A mean dose of 33 +/- 1.3 U Insulin Actrapid Human was given intraperitoneally each day. The procedures for intraperitoneal insulin administration were: (1) with 1,000 ml Ringer lactate; (2) with 1,000 ml 3.86% glucose-containing dialysate, and (3) into an empty peritoneal cavity. The calculation of the intraperitoneal volume was done with a single injection indicator dilution technique in which 100 kBq radioiodinated serum albumin (RISA) was added into the fluid prior to instillation. Free insulin and glucose were analyzed at 16 time intervals in blood and in dialysate during each dwell. After drainage the peritoneal cavity was rinsed with 1,000 ml Ringer lactate followed by two consecutive 5-hour exchanges with 2,000 ml glucose-containing dialysate. Recovery of insulin and RISA was measured in rinsing fluid and in sampled dialysate during the 6-hour dwell. The kinetic calculations made for insulin were disappearance rate (mU/min) from the peritoneal cavity, and appearance rate in circulating blood. After drainage and rinsing, 66.0 +/- 10 and 71.8 +/- 9.8% of the insulin instilled had disappeared after 6 h from the glucose fluid and from the Ringer solution respectively and did not differ significantly. However, the estimated disappearance rate from the peritoneal cavity was significantly higher in Ringer than in glucose from the time interval 120 to 360 min. A high and peak-shaped insulin concentration in the plasma was found following insulin injection into an empty peritoneal cavity, and was significantly higher than when insulin was dissolved in a 1,000-ml fluid volume. However, a higher blood concentration was also found when Ringer was instilled than when a hyperosmolal glucose solution was instilled. A high first-pass elimination in the liver is suggested. In conclusion, fluid volume and also the osmolality of the solution in the peritoneal cavity decreases the transport rate, but not the bioavailability of insulin given intraperitoneally. Both a high peak shape and a continuous insulin appearance in blood can be achieved. It is suggested that there is a high first-pass elimination of insulin during absorption from the peritoneal cavity. However, the values are uncertain and extended investigations must be done. Topics: Adult; Aged; Blood Proteins; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Half-Life; Humans; Infusions, Parenteral; Insulin; Insulin Antibodies; Insulin, Regular, Pork; Iodine Radioisotopes; Male; Metabolic Clearance Rate; Middle Aged; Peritoneal Cavity; Peritoneal Dialysis, Continuous Ambulatory; Recombinant Proteins | 1996 |
Ketoacidosis at diagnosis is predictive of lower residual beta-cell function and poor metabolic control in type 1 diabetes.
To determine the factors at diagnosis predictive of changes in residual beta-cell function and metabolic control in Type 1 diabetes, 125 patients older than 7 years of age consecutively diagnosed between March 1986 and June 1991 were followed prospectively for two years. The effect of age, gender and the presence of ketoacidosis (DKA) and islet-cell antibodies (ICA) on beta-cell function, metabolic control and insulin requirements were studied by multivariate analysis of variance (repeated measurements over time) in 90 patients who completed follow-up. DKA had an independent negative effect on residual beta-cell function over time (p = 0.001). ICA-positive patients had lower residual beta-cell function at the end of follow-up (p < 0.05), but overall differences were not significant. DKA and younger age had an independent negative influence on metabolic control (p < 0.05) and insulin requirements (p < 0.001) over time. It is concluded that residual beta-cell function in Type 1 diabetic patients two years after diagnosis was independently influenced by DKA and ICA at diagnosis. Moreover, DKA and age influenced metabolic control and could thus be used to predict those patients with rapidly deteriorating metabolic control who might benefit from a more intensive therapeutic approach. Topics: Adolescent; Adult; Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies | 1996 |
Frequency of insulin-dependent diabetes mellitus in Turkish adult-onset diabetic population.
The frequency of insulin-dependent diabetes mellitus in the Turkish adult-onset diabetic population has not been assessed previously. In the present study, we retrospectively evaluated the medical records of 801 Turkish patients with adult-onset (> or = 30 years) diabetes to determine the frequency of cases diagnosed as insulin-dependent diabetes. Fifty-two (6.5%) patients met our criteria of adult-onset insulin-dependent diabetes mellitus. At disease onset, 20 patients presented with ketoacidosis (38.5%), while 32 patients (61.5%) were non-ketotic. In the insulin-dependent diabetic group, islet cell antibodies were positive in 10 out of 16 (62.5%) patients studied. In contrast, none of the 16 patients had positive reactions with respect to insulin autoantibodies. Twelve out of 20 patients (60%) had glucagon-stimulated C-peptide levels above 0.6 nmol/l, suggesting a sufficient insulin secretory reserve. In view of these observations, we conclude that insulin-dependent diabetes mellitus is not rare among patients with adult-onset diabetes in the Turkish population. In a majority of cases, the disease onset is non-ketotic. Beta-cell function is relatively preserved, and insulin autoantibodies do not develop at diagnosis. In contrast, islet cell antibodies are frequently present at the onset of clinical insulin-dependent diabetes, possibly indicating continuing beta-cell destruction. Topics: Adult; Age Factors; Age of Onset; Autoantibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glucagon; Humans; Incidence; Insulin Antibodies; Islets of Langerhans; Male; Medical Records; Middle Aged; Turkey | 1996 |
Soluble CD8 antigen, stimulated C-peptide and islet cell antibodies are predictors of insulin requirement in newly diagnosed patients with unclassifiable diabetes.
To evaluate the predictive factors of insulin requirement in newly diagnosed patients with unclassifiable diabetes, 54 consecutive patients, aged less than 35 years, were prospectively followed for 3 years or more. At entry, haemoglobin HbA1c, basal and stimulated C-peptide concentrations, HLA phenotype, islet cell antibodies (ICA) status, and serum levels of soluble CD8 antigen (sCD8) were evaluated. After a median time of 9 (range 2-32) months, 31 patients (group 1) required insulin therapy, whereas 23 patients (group 2) remained non-insulin-requiring after 36 months. Group 1 patients were younger (P < 0.05) and had higher HbA1c and sCD8 serum levels (P < 0.0001), respectively), a higher frequency of ICA positivity and of HLA DR3 and/or DR4 phenotype (P < 0.005 and P < 0.0001, respectively), and lower C-peptide concentrations (P < 0.005 and P < 0.0001, basal and stimulated, respectively) than group 2. The sensitivity, specificity, positive and negative predictive value, and overall accuracy for the subsequent insulin requirement were: sCD8 serum levels (> 737 U/ml), 100%, 65%, 79%, 100% and 85%, respectively; stimulated C-peptide (< 0.60 nmol/l), 71%, 96%, 96%, 74% and 81%, respectively; and ICA positivity (> 20 JDFU), 45%, 91%, 87%, 55% and 65%, respectively. Thus, higher sCD8 serum levels, low stimulated C-peptide concentrations and ICA positivity are the most powerful predictors of subsequent recourse to insulin therapy in young, newly detected patients with unclassifiable diabetes. Topics: Adolescent; Adult; Antigens, CD; Autoantibodies; Biomarkers; Body Mass Index; C-Peptide; CD8 Antigens; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Histocompatibility Testing; HLA-DR3 Antigen; Humans; Insulin; Islets of Langerhans; Male; Predictive Value of Tests; Prospective Studies | 1996 |
Islet allotransplantation in type I diabetic patients: effects of islet cell number on clinical outcome.
Topics: Adult; Blood Glucose; C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glycated Hemoglobin; Graft Rejection; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Male; Postoperative Care; Transplantation, Homologous; Treatment Outcome | 1996 |
Effect of dietary protein intake on insulin secretion and glucose metabolism in insulin-dependent diabetes mellitus.
Adult-onset insulin dependent diabetes mellitus (IDDM) is associated with significant residual insulin secretion. The process leading to the ultimate destruction of B cells may be influenced, among other factors, by the quality and amount of ingested protein. Using a standardized food questionnaire, we matched 13 individuals with normal protein (NP; 0.74 +/- 0.08 g/kg.day) and high protein (HP; 1.87 +/- 0.26 g/kg.day) intake from a sample of 117 newly diagnosed IDDM patients according to sex, age, body mass index, and energy intake. Nondiabetic control subjects were also selected. Dietary habits did not change significantly over an observation period of 1 yr. Glucagon-stimulated C peptide was significantly higher in the NP compared to the HP group (0.71 +/- 0.06 vs. 0.50 +/- 0.04 nmol/L; P < 0.002). NP food was associated with higher overall insulin sensitivity in both patients and nondiabetic subjects. Hepatic glucose output was significantly increased in individuals with HP intake [HP IDDM, 14.8 +/- 0.6 vs. NP IDDM, 12.7 +/- 0.7 (P < 0.01); HP control, 12.2 +/- 0.5 vs. NP control, 10.9 +/- 0.5 (P < 0.01 mumol/kg.min). Insulin-mediated suppression of hepatic glucose production was impaired in diabetic patients with high protein intake, but not in patients with normal protein diet. Gluconeogenesis estimated from 13C enrichment in breath and plasma was increased in individuals on a HP diet. We conclude that a NP diet is accompanied by delayed progression of the continuous loss of endogenous insulin in IDDM. This phenomenon is possibly due to decreased insulin demand on the B cells and/or reduced hepatic glucose production favoring enhanced insulin sensitivity. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diet Records; Dietary Proteins; Female; Glucagon; Gluconeogenesis; Glucose; Humans; Insulin; Insulin Secretion; Liver; Male | 1996 |
Ketoacidosis at the diagnosis of type 1 (insulin dependent) diabetes mellitus is related to poor residual beta cell function. Childhood Diabetes in Finland Study Group.
The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Drug Administration Schedule; Educational Status; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Infant; Insulin; Islets of Langerhans; Male; Parents; Prognosis | 1996 |
Basal and stimulated endocrine metabolic function in recipients of pancreatico-duodenal grafts.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Duodenum; Female; Follow-Up Studies; Glucose; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Kidney Failure, Chronic; Kidney Transplantation; Male; Pancreas Transplantation; Time Factors | 1996 |
Glucagon-induced plasma C-peptide response in diabetic patients. Influence of body weight and relationship to insulin requirement.
Topics: Adult; Age of Onset; Body Mass Index; Body Weight; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Humans; Insulin; Male; Obesity | 1996 |
Alterations in the patterns of insulin secretion before and after diagnosis of IDDM.
To study the natural history of beta-cell dysfunction in an individual who developed insulin-dependent diabetes mellitus (IDDM) over a 13-month period while under observation.. Insulin secretion rates (ISR) in response to intravenous glucose and mixed meals were estimated by deconvolution of C-peptide levels.. When fasting glucose and glycosylated hemoglobin concentrations were still within the normal range, insulin secretory responses to intravenous glucose infusion were reduced, but 80- to 100-min secretory oscillations could still be detected. Sequential glucose infusion studies over a 3-month period demonstrated a progressive reduction in insulin secretion. The tight temporal coupling between ultradian oscillations in ISR and glucose observed in nondiabetic subjects was lost. In response to mixed meals, the oscillatory pattern of secretion was preserved, but the magnitude of the secretory responses was reduced.. Our results indicate that despite the lower absolute secretory rates, ultradian ISR oscillations persist in the period before and immediately after the onset of IDDM in this subject, but they are less tightly coupled to glucose than in nondiabetic subjects. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diet; Glucose; Humans; Infusions, Intravenous; Insulin; Insulin Secretion; Male; Proinsulin | 1995 |
Prevalence of antibodies to glutamic acid decarboxylase in women who have had gestational diabetes.
Our purpose was to determine the prevalence of autoantibodies to glutamic acid decarboxylase in women who had had gestational diabetes, including those in whom insulin-requiring or non-insulin-requiring diabetes mellitus has since developed.. The study group comprised 734 women with previous gestational diabetes who were consecutive attendees to a follow-up clinic. These women were tested for autoantibodies to glutamic acid decarboxylase with a radioimmunoprecipitation assay. We similarly tested 104 women in whom permanent diabetes mellitus developed after gestational diabetes, of whom 20 were using insulin and 84 were not. Those using insulin also had fasting C-peptide levels measured.. Thirteen of the 734 (1.8%, 95% confidence interval 0.9% to 3.0%) women with previous gestational diabetes were positive for autoantibodies to glutamic acid decarboxylase. Of the 20 women with diabetes treated with insulin, 12 had insulin deficiency confirmed by low levels of C peptide; all 12 were positive for autoantibodies to glutamic acid decarboxylase. Of the 84 women with diabetes not requiring insulin, 6 (7.1%, 95% confidence interval 2.7% to 14.9%) were positive for autoantibodies to glutamic acid decarboxylase.. The prevalence of autoantibodies to glutamic acid decarboxylase in women with previous gestational diabetes was 1.8%. Our data also showed that insulin-dependent diabetes mellitus will develop in 1.7% of women with gestational diabetes. A positive test for autoantibodies to glutamic acid decarboxylase may help in the early identification of insulin-dependent diabetes mellitus. Adult-onset insulin-dependent diabetes mellitus developed in only 5.2% (12/230) of women with previous gestational diabetes who later had diabetes mellitus. Topics: Adult; Autoantibodies; C-Peptide; Confidence Intervals; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Follow-Up Studies; Glucose Intolerance; Glucose Tolerance Test; Glutamate Decarboxylase; Humans; Middle Aged; Pregnancy; Reference Values; Time Factors | 1995 |
Catheter complications associated with implantable systems for peritoneal insulin delivery. An analysis of frequency, predisposing factors, and obstructing materials.
To evaluate catheter survival and identify mechanisms involved in catheter obstructions during a 109.8 patient-year experience with implanted pumps for peritoneal insulin delivery.. Fifty-one type I diabetic patients were recruited in feasibility studies of two models of implanted systems for peritoneal insulin delivery. Both systems had a silicone-coated polyethylene catheter and infused Hoechst 21 PH neutral insulin (U400 or U100). Catheter obstruction was suspected each time the increase of insulin flow rate over 50% of usual need was insufficient to correct an impairment of glycemic control in the absence of of intercurrent factors. A laparoscopic examination was then systematically performed under general anesthesia. The disclosed material occluding the catheter was submitted to a pathological analysis. By actuarial analysis, we examined the estimated effects of the potential determinants of the catheters' duration of proper operation on catheter survival.. Over an implantation duration of 25.8 +/- 14.0 months (mean +/- SD), 34 catheter obstructions were diagnosed in 24 patients, resulting in an incidence of 31 events per 100 patient-years. Fifty percent survival rate of the first implanted catheter was 27 months (95% confidence interval [CI]: 19-32) on actuarial analysis. Six catheters were cleared under laparoscopy and 24 were replaced, while 2 systems were definitively explanted and 2 combined replacements of pump and catheter were performed because of an associated pump slowdown. In five cases, an alkaline rinse procedure of the pump was necessary after catheter replacement to restore usual insulin needs, suggesting an associated insulin aggregation in the pump. Twenty obstructions were due to a fibrin clot at the catheter tip, and 14 obstructions were created by a tissue encapsulation around the catheter. A previous experience of peritoneal insulin infusion from portable pumps or a longer duration of diabetes ( > 21 years) both appeared as conditions significantly reducing the time of a catheter's proper operation (P < 0.01 and P < 0.05, respectively) either by tip obstructions or by encapsulations. Pathological analysis of catheter encapsulations showed a collagen fibrosis in all studied patients (n = 11), which was associated with a lymphocytic infiltrate in five patients and also with anti-insulin immunoreactive amyloid deposits in four patients. Catheter tip clots were composed of fibrinlike material, nonreactive to anti-insulin antibodies.. Catheter obstruction is a frequent adverse technical event occurring with implanted insulin pumps. Progress is expected in the biocompatibility of catheter material and more specifically in the stability of insulin preparations to prevent immuno-inflammatory reactions and insulin amyloid deposits that appear to be involved in catheter failures. Topics: Actuarial Analysis; Adult; Amyloid; C-Peptide; Catheters, Indwelling; Diabetes Mellitus, Type 1; Equipment Failure; Feasibility Studies; Female; Follow-Up Studies; Humans; Insulin Infusion Systems; Male; Probability; Retrospective Studies; Risk Factors; Time Factors | 1995 |
Prevalence of IDDM in adults in the community.
Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Israel; Middle Aged; Prevalence; United States | 1995 |
Mitochondrial DNA, diabetes and pancreatic pathology in Kearns-Sayre syndrome.
Mitochondrial DNA (mtDNA) mutations are associated with diabetes mellitus but their role in the onset of hyperglycaemia is unclear. A patient presented with diabetes requiring insulin therapy at the age of 7 years, followed by diagnosis of Kearns-Sayre syndrome (KSS). Beta-cell function was absent at age 19 years as shown by lack of glucose-stimulated C-peptide secretion. Following development of a cardiac conduction defect the patient died aged 21 years. Analysis of mtDNA in blood and several tissues revealed related re-arranged deletions, duplications and deletion dimers in addition to normal mtDNA with the highest levels of duplications in kidney and blood. Pancreatic tissue from the KSS patient was compared with tissue from an insulin-dependent diabetic patient with a similar clinical history of diabetes. Islets in KSS were small, regular in shape and contained predominantly glucagon-containing cells with no evidence of beta cells. In comparison, a small number of beta cells were present in some of the larger more irregularly-shaped islets from the insulin-dependent diabetic patient. These data together suggest that in KSS the loss of beta cells at the onset of diabetes is less disruptive to islet architecture: a small proportion of beta cells or their gradual destruction over a long period would allow retention of islet shape. Abnormal function of the re-arranged mtDNA could affect both development and function of pancreatic islet cells since glucose-stimulated insulin secretion is energy dependent. Topics: Adult; Age of Onset; C-Peptide; Child; Diabetes Mellitus, Type 1; DNA, Mitochondrial; Female; Gene Rearrangement; Humans; Immunoenzyme Techniques; Insulin; Islets of Langerhans; Kearns-Sayre Syndrome; Kidney; Organ Specificity; Pancreas; Sequence Deletion | 1995 |
Clinical studies of human islet transplantation.
Recent advantages in techniques for the isolation of human pancreatic islets of Langerhans have led to the introduction of clinical trials of islet transplantation in diabetic patients who are already immunosuppressed because they have received a kidney transplant for end-stage renal failure. This paper describes the techniques used and the outcome in three diabetic patients who have received intraportal islet transplants. The first two patients received islets pooled from multiple cadaveric organ donors, the third patient received islets from a single well major histocompatibility complex (MHC) matched donor. The islet grafts in the first two patients failed rapidly, almost certainly due to rejection. The islet graft in the third patient continues to function after 18 months. Taken together with the worldwide experience, the results of this small series suggest that islet transplantation from a single well MHC matched donor may be optimal. For this approach to be a realistic option, techniques for islet isolation need to be further improved so that large numbers of islets can be regularly isolated from a single pancreas. The collagenase digestion phase of the islet isolation process is the major limiting factor and this area requires further detailed research. Topics: Adult; Blood Group Antigens; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Graft Rejection; Histocompatibility Testing; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Treatment Outcome | 1995 |
Potential of endogenous peptides to induce immunological reactions as observed in type I diabetes, a study in mice.
The initiation of the immunological processes leading to type I diabetes is still not understood. The potential of endogenous peptides to induce autoimmune reactions was investigated. Peptides generated in the beta-cell by proteolysis could bypass antigen processing by binding to MHC molecules. Selfreactive T and B lymphocytes could be activated by these MHC peptide complexes. The antibody production of peptide-induced B lymphocytes was investigated in mice. Insulin A chain, B chain, C-peptide or amylin were tested for potential induction of antibodies to antigens other than the immunizing peptide. Lymph node B lymphocytes were characterized with an avidin at solid phase ELISA-spot assay. In BALB/c mice insulin A chain induced more spots to B29biotin- and to B1biotinDOP insulin than to A chain itself (P < 0.01, each). Spots to insulin were not inhibited by insulin A chain. Spots to B1DOP insulin were not inhibited by A chain or insulin, excluding crossreaction. Inbred strains of mice with H-2d but not with H-2k or H-2b showed the effect. Application of A chain without adjuvant produced the effect. The antigens recognized by A chain-induced B lymphocytes had to be included in the natural IgM antibody repertoire of the spleen. The study supports the hypothesis that endogenous breakdown peptides can bypass antigen processing resulting in an autoreactive T-B cell interaction. A potential to induce type I diabetes could exist. Topics: Amyloid; Animals; Antibodies; Antibody Formation; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Hypoglycemic Agents; Immunity, Cellular; Insulin; Islet Amyloid Polypeptide; Male; Mice; Mice, Inbred Strains | 1995 |
Serial changes in the prevalence of islet cell antibodies and islet cell antibody titer in children with IDDM of abrupt or slow onset.
To elucidate the significance of clinical and immunogenic heterogeneity in Japanese children with insulin-dependent diabetes mellitus (IDDM).. Serial changes in the prevalence of islet cell antibodies (ICAs) and in ICA titer were monitored for 10 years after diagnosis in 34 IDDM children, 17 with abrupt onset and 17 with slow onset, whose durations of disease were > 5 years.. In slow-onset IDDM children, enough beta-cell function was maintained in the early phase of the disease within 2 years after diagnosis. There was a high prevalence of ICAs in children with both forms of IDDM at the time of diagnosis (abrupt onset 94%; slow onset 82%). However, the decline in the frequency of ICAs in slow-onset IDDM seemed less marked than in abrupt-onset IDDM after a duration of > or = 1 year (47 vs. 82%, 1-3 years; 24 vs. 47%, 3-5 years; 24 vs. 47%, 5-7 years; 18 vs. 53%, 7-10 years, P < 0.05). In terms of changes in ICA titer, abrupt-onset IDDM children initially had high ICA levels of 160-320 Juvenile Diabetes Foundation units (JDF U), but these titers decreased rapidly after the 1st year. On the other hand, slow-onset IDDM children tended to continue to be ICA+ for a relatively long period with low titers of 20-40 JDF U. Among 12 children who remained ICA+ for > 5 years, slow onset was noted in 67% while abrupt onset was seen in only 33%.. From these results, we speculated that changes in ICA titer reflect the slow autoimmune destruction of pancreatic beta-cells. It may be probable that immunogenic factors as well as environmental factors could affect the clinical features in the early phase of IDDM in children. Topics: Age of Onset; Autoantibodies; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Disease Progression; Eating; Female; Humans; Male; Time Factors | 1995 |
Exocrine pancreatic and beta-cell function in malnutrition-related diabetes among north Indians.
To compare the pancreatic exocrine and beta-cell function in the two variants of malnutrition-related diabetes mellitus (MRDM): fibrocalculous pancreatic diabetes (FCPD) and protein-deficient pancreatic diabetes (PDPD).. Fecal chymotrypsin (FCT) and fasting C-peptide levels were measured in 20 consecutive patients with FCPD and 19 with PDPD. FCPD was diagnosed by pancreatic calcification on ultrasonography, while the diagnosis of PDPD was made on the basis of low body mass index, severe diabetes requiring insulin therapy, and ketosis resistance on interruption of insulin. Twenty patients with type I diabetes and 32 healthy subjects served as control subjects.. Both FCPD and PDPD patients had diminished levels of FCT when compared with those of control subjects and patients with type I diabetes. However, FCT levels were significantly lower in subjects with FCPD (median 0.4 U/g, range 0-8.9 U/g), in comparison with those with PDPD (4.7 U/g, 0.6-40.5 U/g; P < 0.001). Of the FCPD patients, 13 of 20 (65%) had severe exocrine pancreatic deficiency (FCT < 1 U/g) vs. 3 of 19 (15.8%) PDPD subjects (P < 0.01). In comparison with control subjects, fasting serum C-peptide levels were significantly diminished in both MRDM groups. However, C-peptide levels in subjects with FCPD (mean +/- SE, 0.22 +/- 0.04 nmol/l) and PDPD (0.26 +/- 0.04 nmol/l) were comparable.. Among the two variants of MRDM, subjects with FCPD have severe pancreatic exocrine deficiency in comparison with those with PDPD, even though their C-peptide levels are comparably diminished. This suggests that the pathogenesis of these two entities may differ or that the genetic and/or environmental factors leading to exocrine damage are different. Topics: Adult; Blood Glucose; Body Mass Index; C-Peptide; Chymotrypsin; Diabetes Mellitus; Diabetes Mellitus, Type 1; Feces; Female; Glycated Hemoglobin; Humans; India; Insulin; Insulin Secretion; Islets of Langerhans; Male; Nutrition Disorders; Pancreas; Pancreatic Diseases; Reference Values; Statistics, Nonparametric | 1995 |
Residual beta-cell function and HLA-A24 in IDDM. Markers of glycemic control and subsequent development of diabetic retinopathy.
To identify risk factors for diabetic retinopathy in insulin-dependent diabetes mellitus (IDDM), we studied the relationships among residual beta-cell function, human leukocyte antigen (HLA), long-term glycemic control, and development of diabetic retinopathy in 128 IDDM patients. Residual beta-cell function was assessed by serum C-peptide immunoreactivity (CPR) response to a 100-g oral glucose load (delta CPR). The patients were stratified into three groups: those with delta CPR of < 0.033 nmol/l (group 1, n = 50), those with delta CPR of 0.033-0.1 nmol/l (group 2, n = 38), and those with delta CPR of > 0.1 nmol/l (group 3, n = 40). The cumulative incidence rate of background retinopathy was higher in the order of groups 1, 2, and 3 (P = 0.032). Group 1 progressed to preproliferative retinopathy at an earlier stage than did groups 2 and 3 combined (P = 0.028). Further progression to proliferative retinopathy tended to be earlier in group 1 than in groups 2 and 3 combined (P = 0.083). The mean HbA1c value rose from 9.01 +/- 1.06% (mean +/- SD) in group 3 to 9.75 +/- 0.79% in group 2 to 10.48 +/- 1.12% in group 1 (P < 0.0001). In group 1, 89.6% of the patients had HLA-A24, whereas 50 and 43.6% of the patients had this antigen in groups 2 and 3 respectively (P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Age of Onset; Biomarkers; Blood Glucose; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Follow-Up Studies; Glycated Hemoglobin; Histocompatibility Testing; HLA-A Antigens; HLA-A24 Antigen; Humans; Incidence; Islets of Langerhans; Life Tables; Male; Middle Aged; Predictive Value of Tests; Proportional Hazards Models; Risk Factors; Time Factors | 1995 |
Portal insulin concentrations rather than insulin sensitivity regulate serum sex hormone-binding globulin and insulin-like growth factor binding protein 1 in vivo.
Serum sex hormone-binding globulin (SHBG) and insulin-like growth factor-binding protein 1 (IGFBP-1) concentrations have been suggested to be useful markers of insulin sensitivity. As the production of both proteins is inhibited by insulin in the liver, we postulated that their concentrations reflect whole body insulin sensitivity only when the latter parallels changes in endogenous insulin secretion. To test this hypothesis, we determined SHBG and IGFBP-1 concentrations, whole body insulin sensitivity (euglycemic insulin clamp; serum free insulin, approximately 400 pmol/L), and serum insulin and C peptide concentrations in 13 type 1 diabetic patients lacking endogenous insulin secretion and 34 matched normal subjects. Whole body insulin sensitivity was 50% lower in the type 1 diabetic patients (20 +/- 3 mumol/kg.min) than that in the normal subjects (40 +/- 3 mumol/kg.min; P < 0.001). Despite this, serum SHBG (45 +/- 4 vs. 29 +/- 2nmol/L; P < 0.002) and IGFBP-1 (14 +/- 3 vs. 2 +/- 1 micrograms/L; P < 0.002) concentrations were increased in the type 1 diabetic patients. In the normal subjects, SHBG (r = -0.49; P < 0.01) and IGFBP-1 (r = -0.49; P < 0.01) were inversely correlated with serum C peptide and positively correlated with whole body insulin sensitivity (r = 0.54; P < 0.005 and r = 0.54; P < 0.005, respectively). In the type 1 diabetic patients, SHBG and IGFBP-1 concentrations were disproportionately increased when related to insulin sensitivity, but appropriate when related to estimated portal insulin concentrations. Serum T4, free testosterone, and estradiol concentrations were similar in both groups. We conclude that SHBG and IGFBP-1 reflect hepatic insulinization and can only be used as markers of insulin sensitivity in individuals with intact insulin secretion. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Estradiol; Humans; Insulin; Insulin-Like Growth Factor Binding Protein 1; Male; Osmolar Concentration; Portal Vein; Reference Values; Sex Hormone-Binding Globulin; Testosterone; Thyroxine | 1995 |
Chronic calcific pancreatitis of the tropics (CCPT): spectrum and correlates of exocrine and endocrine pancreatic dysfunction.
The exocrine and endocrine pathophysiology of chronic calcific pancreatitis of the tropics (CCPT) remains elusive. The objective of this study was to evaluate the spectrum and correlates of the exocrine and endocrine pancreatic dysfunction in CCPT. Thirty-seven consecutive patients with a clinico-radiological diagnosis of CCPT were stratified into three subgroups: CCPT-normal glucose tolerance (NGT), CCPT-abnormal glucose tolerance (IGT) and CCPT-diabetes mellitus (DM). Ten ketosis resistant young diabetic (KRDY) patients, 10 classical insulin dependent diabetes mellitus (IDDM) patients and 18 healthy matched controls were included for comparison. Fecal chymotrypsin (FCT) levels and blood C-peptide levels (basal and post i.v. glucagon stimulation) were estimated for assessing the exocrine and endocrine pancreatic functions, respectively. Sonography was performed to evaluate the pancreatic size and ductal diameter. Pancreatic exocrine-endocrine correlation was examined by studying the C-peptide/fecal chymotrypsin ratio (CP/FCT) (CP/FCT of normal controls = 1). Mean FCT levels in all 3 subgroups of CCPT (NGT: 3.4 micrograms/g; IGT: 0.82 microgram/g; DM: 2.4 micrograms/g) were very low (87-96% reduction in exocrine pancreatic dysfunction; mean FCT in healthy controls was 22.8 micrograms/g) (P < 0.0001). In contrast, KRDY and IDDM patients displayed 50-54% reduction in pancreatic acinar function (P < 0.001). Basal and stimulated C-peptide levels progressively fell in the 3 CCPT subsets (NGT: 0.23 and 0.46 > IGT: 0.14 and 0.29 > DM 0.10 and 0.14) (P < 0.01). CCPT patients exhibited pancreatic atrophy and ductal dilation (> 3 mm).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Age of Onset; Analysis of Variance; Blood Glucose; C-Peptide; Calcinosis; Chronic Disease; Chymotrypsin; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glucose Intolerance; Glucose Tolerance Test; Humans; Islets of Langerhans; Male; Pancreas; Pancreatitis; Reference Values; Tropical Climate; Ultrasonography | 1995 |
Clinical heterogeneity of insulin dependent diabetes mellitus in Korea.
This study was undertaken to find out how many current Korean patients with insulin dependent diabetes mellitus (IDDM) had a previous history of non-insulin requiring phase. Fasting serum C-peptide levels were measured in the 2300 diabetic patients during the visit to the Asan Medical Center, Seoul, Korea. Fifty-nine patients showed fasting serum C-peptide levels below 0.13 nmol/l. These 59 patients were classified further into two groups according to their history of insulin requirement: group A who required insulin within 1 year after diagnosis or presented initially as diabetic ketoacidosis and group B who had non-insulin requiring phase at least for 1 year (median: 5 years; range: 1-23 years). Twenty-six patients (44%) were classified into group A and 27 patients (46%) into group B. Median age of onset was 26 years (range: 10-50 years) and 45 years (range: 23-73 years) in groups A and B, respectively (P < 0.001). While the two groups had similar values in the current and maximum body mass indices, sex ratio and the prevalence of islet cell antibodies, 58% of the group A and 7% of the group B patients had histories of diabetic ketoacidosis. These results suggest a clinical heterogeneity in patients with IDDM in Korea. Topics: Adolescent; Adult; Age of Onset; Aged; Body Mass Index; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Fasting; Female; Humans; Insulin; Korea; Male; Middle Aged | 1995 |
Insulin-like growth factor-I is related to glycemic control in children and adolescents with newly diagnosed insulin-dependent diabetes.
To address the relationship of insulin-like growth factor-I (IGF-I) to diabetes control, we determined IGF-I levels in 137 subjects age 17 yr and younger with recently diagnosed insulin-dependent diabetes mellitus in a population-based cohort study between 3 and 11 months after diagnosis (mean 4.9 months). Initial determinations of IGF-I, 24-h urine C-peptide and microalbuminuria, age, sex, height, weight, body mass index, pubertal stage, and glycosylated hemoglobin (GHb) were obtained. IGF-I levels ranged from 11-439 ng/mL, were strongly related to age (r = 0.74, P < 0.001), and were higher in females than males at any given age (P < 0.01). IGF-I was inversely related to GHb (partial r = -0.43, P < 0.001) after adjustment for sex and age. The relationship between IGF-I and GHb did not change between age groups (< 6, 6-9, > or = 10 yr of age; P = 0.50), and it did not change between prepubertal and pubertal subjects (P = 0.95). IGF-I was not related to 24-h urine C-peptide or microalbuminuria. These results suggest that lower IGF-I levels are related to poorer metabolic control of diabetes in the period following insulin-dependent diabetes mellitus diagnosis in all young persons regardless of age or pubertal status. Topics: Adolescent; Age Factors; Albuminuria; Blood Glucose; Body Mass Index; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin-Like Growth Factor I; Male; Puberty; Radioimmunoassay; Sex Characteristics; Sex Factors; Time Factors | 1995 |
Relationships among 64k autoantibodies, pancreatic beta-cell function, HLA-DR antigens and HLA-DQ genes in patients with insulin-dependent diabetes mellitus in Korea.
Among autoantibodies detected in patients with insulin-dependent diabetes mellitus (IDDM), antibodies to 64,000(Mr) islet protein(64k), now recognized as glutamic acid decarboxylase(GAD), appear to be an even more predictive marker of IDDM than islet cytoplasmic antibody (ICA) or insulin autoantibody (IAA). We examined the relationships among 64k autoantibodies, pancreatic beta-cell function, HLA-DR antigens and HLA-DQ genes in patients with IDDM in Korea.. To identify the 64k autoantibody, the immunoprecipitation method was performed for 35 patients with IDDM and 10 normal controls. In patients with IDDM, serum C-peptide levels were measured and HLA-DR typings and HLA-DQA1 and DQB1 gene typings were performed.. 12 of 35 (34%) patients with IDDM were positive for 64k autoantibody in contrast to none of 10(0%) normal controls. There were no differences in residual pancreatic beta-cell function between 64k autoantibody positive and negative groups. 64k autoantibody was detected more frequently in patients with recent (duration < 6 months, 10/25[40%]) and young -aged(aged < 15 years, 7/18[39%]) onset of IDDM. All of 3(100%) patients with HLA-DR3/DR4 heterotypes were positive in 64k autoantibody, in contrast to 1 of 7(14%) patients without HLA-DR3 nor DR4. The frequencies of HLA-DQA1*0301, HLA-DQB1*0201, DQB1* 0302 and DQB1*0303 gene types were higher in patients with 64k autoantibody (12/12 [100%]) vs. without 64k autoantibody 18/22[81%], 5/11[45%] vs. without 64k autoantibody 5/22[23%], 5/11[45%] vs. without 64k autoantibody 8/22[36%] and 6/11 [55%] vs. without 64k autoantibody 9/22[41%].. There results suggest that 64k autoantibodies have some relationship with HLA-DR, DQA1 and DQB1 genes, but not with residual pancreatic beta-cell function in Korean patients with IDDM. Topics: Adolescent; Adult; Alleles; Animals; Antibody Specificity; Asian People; Autoantibodies; Autoantigens; Autoimmune Diseases; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Disease Susceptibility; Female; Genetic Predisposition to Disease; Glutamate Decarboxylase; HLA-DQ alpha-Chains; HLA-DQ Antigens; HLA-DQ beta-Chains; HLA-DR Antigens; Humans; Islets of Langerhans; Korea; Male; Rats; White People | 1995 |
An 8-year follow-up of anti-insulin antibodies in diabetic children: relation to insulin autoantibodies, HLA type, beta-cell function, clinical course and type of insulin therapy.
In 105 children and adolescents with IDDM, insulin antibodies were detected as a percentage of radiolabelled insulin both at onset of disease and during the first 8 years of treatment. At diagnosis, 29 patients (27%) were insulin autoantibody positive (IAA+). An inverse relationship was found between IAA levels and age at diagnosis. No significant correlation was seen between IAA positivity and HLA antigens, while there was a negative correlation between IAA and C-peptide levels in the second year of the disease. The percentage of insulin antibody (IA) positive patients increased after insulin administration, with a maximum peak between the first and second year of the disease. The IA response to insulin therapy was similar in IAA+ and IAA- patients, while it was greater in younger children. No relationship was found between IA levels and haemoglobin A1c values, daily insulin requirement, HLA and early complications. No difference in either percentage of positivity or IA levels was seen in patients treated continually for the first 5 years of the disease with monocomponent porcine insulin or human insulin. A negative correlation was found between IA and C-peptide levels in the first and second years of the disease. In conclusion, we have shown that, even after many years of disease, neither IAA nor IA, induced in equal measures by current human insulin preparations, have significant effects on the clinical course of the disease. Topics: Adolescent; Antibodies; Antibody Formation; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA Antigens; Humans; Infant; Insulin; Male; Time Factors | 1995 |
Subclinical nerve dysfunction in children and adolescents with IDDM.
The purpose of this study was to investigate whether young insulin-dependent diabetic patients still develop peripheral nerve dysfunction when using modern multiple insulin injection therapy and to elucidate if this correlated with various disease parameters. Seventy-five patients, 7 to 20 years old with a duration of diabetes of more than 3 years, and 128 age-matched healthy control subjects underwent bilateral studies of median, peroneal, and sural nerves. Presence of diabetes lowered motor conduction velocity (p < 0.0001), sensory conduction velocity (p < 0.0001) and sensory nerve action potential (p < 0.05) in all examined nerves. The mean change in conduction velocity induced by diabetes was -4.8 m/s in the peroneal nerve, -3.3 m/s in the median motor nerve, -2.6 m/s in the sural nerve and -2.4 m/s in the median sensory nerve. Fifty-seven percent of the patients had abnormal conduction (values outside 95% predictive interval) which was seen most often in the motor nerves, especially in the peroneal nerve (41%) followed by the median nerve (24%). In multiple regression analysis, long-term poor metabolic control and increased body length correlated with nerve dysfunction identified in most examined parameters. Three patients had signs or symptoms suggestive of neuropathy. It is concluded that despite modern multiple insulin injection therapy, with reasonably good metabolic control, nerve dysfunction is still common in children and adolescents with insulin-dependent diabetes mellitus. Risk factors are increased height and long-term poor metabolic control. Topics: Adolescent; Adult; Age of Onset; Blood Glucose; Body Weight; C-Peptide; Case-Control Studies; Child; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Female; Functional Laterality; Glycated Hemoglobin; Humans; Male; Median Nerve; Motor Neurons; Neural Conduction; Neurons, Afferent; Patient Dropouts; Peroneal Nerve; Regression Analysis; Sural Nerve | 1995 |
Effects of personality on metabolic control in IDDM patients.
The aim of this study was to evaluate the relationship between poor metabolic control and maladaptive personality traits (according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition-Revised) in an adult-onset insulin-dependent diabetes mellitus sample group (n = 77).. Metabolic control was evaluated through glycosylated hemoglobin (HbA1c). Personality traits were assessed with the Personality Diagnostic Questionnaire-Revised, a self-administered questionnaire. Residual pancreatic secretion (fasting serum C-peptide) was also evaluated.. Principal components analysis revealed three personality profiles: "withdrawn-suspicious" (P1), "dramatic-dependent" (P2), and "aggressive-irresponsible" (P3). Multiple linear regression analysis showed that C-peptide levels and P2 personality profiles were significant and independent predictors of HbA1c plasma levels: P2 predicted high HbA1c values and C-peptide predicted low HbA1c levels.. These data suggest that a P2 personality profile is a significant predictor of poor metabolic control. Topics: Adult; Aggression; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Personality; Personality Inventory; Regression Analysis; Surveys and Questionnaires | 1995 |
Effect of genetic risk load defined by HLA-DQB1 polymorphism on clinical characteristics of IDDM in children.
Clinical and autoimmune characteristics of 150 diabetic children of mean age 7.8 years (SD 4.1 years) were recorded at clinical manifestation and during the first 2 years of IDDM in order to investigate whether subjects with high risk HLA-DQB1 genotypes differ from those without these risk markers. When comparing subjects with the DQB1*0302/0201, DQB1*0302/x, DQB1*0201/x, or other DQB1 genotypes (x = no protective allele), no differences were found in the age of the subjects at diagnosis, the duration of hyperglycaemic symptoms, or the length of clinical remission. The frequency of islet cell antibodies (ICA) and quantitative serum levels of these antibodies were of the same magnitude in all four groups. During the initial 2 years of IDDM serum C-peptide concentrations were observed to be inversely related to the degree of genetic risk (P < 0.001 in two-way analysis of variance for repeated measures), the lowest C-peptide levels being observed in the group of DQB1*0302/0201 heterozygotes (P < 0.001 vs. DQB1*0201/x; P < 0.01 vs. DQB1*0302/x; P = 0.05 vs. others). On the other hand, the subjects with the DQB1*0201 genotype had the highest serum C-peptide concentrations, the levels being even higher than those of the patients carrying neutral or protective DQB1 genotypes (P < 0.01). These subjects also had lower daily insulin doses and blood glycated haemoglobin A1 (HbA1) levels over the initial 2 years of the disease when compared with the DQB1*0302/0201 heterozygotes (P < 0.05 and P < 0.01, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Alleles; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Genotype; Histocompatibility Testing; HLA-DQ Antigens; HLA-DQ beta-Chains; Humans; Infant; Male; Polymorphism, Genetic; Risk Factors | 1995 |
Natural course of insulin sensitivity and insulin reserve in early insulin-dependent diabetes mellitus.
Preservation of endogenous insulin in insulin-dependent diabetes mellitus (IDDM) may prevent the occurrence of diabetes-related complications. Therefore, it is important to known about insulin reserve and insulin sensitivity at clinical manifestation. Twenty-four patients (aged 23 +/- 6 years) were evaluated for 2 years starting at the day of clinical manifestation. Insulin secretion was stimulated by glucagon, arginine, and glucose on separate days. Insulin sensitivity was evaluated by hyperinsulinemic-euglycemic clamp. Two control groups were established, one consisting of age-, weight-, and sex-matched healthy individuals, the other of patients with diabetes of long duration (6 to 13 years). Sensitivity improved from 30% of normal at baseline to 84% after only 2 weeks in the newly manifested patients. Subsequently, insulin released by nonglucose stimuli increased by 75%. Glucose-induced first-phase insulin secretion did not recover. After 2 years, sensitivity was 20% less than normal and glucagon-stimulated C-peptide (GSCP) was 0.64 +/- 0.20 nmol/L (0.41 +/- 0.19 at baseline, P < .002). Insulin sensitivities in euglycemic and hyperglycemic conditions were closely correlated. In conclusion, improvement of insulin sensitivity precedes and is possibly a prerequisite for the recovery of residual insulin in early IDDM. Topics: Adult; Arginine; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Clamp Technique; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Longitudinal Studies; Male; Reference Values; Regression Analysis; Time Factors | 1995 |
Day-to-day variation of insulin sensitivity in patients with type 1 diabetes: role of gender and menstrual cycle.
The aim of the present study was to compare the day-to-day variations of the insulin sensitivity in male and female Type 1 diabetic patients and to assess the insulin sensitivity in the follicular and luteal phases of the menstrual cycle. Ten male and 20 female Type 1 diabetic patients participated in the study. The insulin sensitivity was assessed by the insulin (0.4 mU kg-1 min-1)-glucose/(4.5 mg kg-1 min-1)-infusion test (IGIT). In 5 of the female patients, a simultaneous i.v. influsion of somatostatin (100 micrograms h-1) was given (SIGIT). Each patient was studied twice, with 2 weeks separating the two tests. The day-to-day variations of the insulin sensitivity were almost identical in the male and female patients, the coefficients of variation being 13% in both groups. In 15 of the female patients, ovulation occurred. In these women, the mean blood-glucose levels between 120 and 240 min after the onset of the IGIT/SIGIT were 9.8 +/- 1.1 mmol l-1 in the follicular phase and 10.3 +/- 1.0 mmol l-1 in the luteal phase, n.s. (95% confidence interval for the difference (luteal-follicular) -0.8-1.9 mmol l-1). Although the present study cannot exclude minor changes of insulin sensitivity during the menstrual cycle, our results suggest that the changes of the metabolic control during the menstrual cycle, experienced by many women with Type 1 diabetes, are largely attributable to mechanisms other than variations of insulin sensitivity. Topics: Adult; Blood Glucose; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Estradiol; Female; Follicular Phase; Glycated Hemoglobin; Humans; Insulin; Luteal Phase; Male; Menstrual Cycle; Progesterone; Reproducibility of Results; Sex Characteristics | 1995 |
Glucagon-like peptide I reduces postprandial glycemic excursions in IDDM.
Effects of human glucagon-like peptide I (GLP-I)(7-36)amide were examined in volunteers having insulin-dependent diabetes mellitus (IDDM) with residual C-peptide (CP) secretion (n = 8, 7 men and 1 woman; age, 31 +/- 1.4 years; body mass index, 24.7 +/- 0.7 kg/m2; duration of diabetes, 3.2 +/- 0.8 years; insulin dose, 0.41 +/- 0.05 U.kg-1.day-1; meal-stimulated CP, 1.0 +/- 0.2 nmol/l [means +/- SE]). After a mixed meal (Sustacal, 30 kJ/kg body wt), intravenous injection of GLP-I, 1.2 pmol.kg-1.min-1 through 120 min, virtually abolished increments of plasma glucose, CP, pancreatic polypeptide (PP), and glucagon concentrations, with no significant effect on plasma gastrin levels during the infusions. At reduced dosage (0.75 pmol.kg-1.min-1), GLP-I had lesser effects on plasma glucose and CP levels. On cessation of intravenous GLP-I infusions after the meals, plasma glucose, CP, PP, and glucagon concentrations rebounded toward control levels by 180 min, and the response of plasma gastrin was prolonged. These rebound responses are consistent with intestinal delivery of food retained in the stomach on escape from inhibition of gastric emptying by GLP-I. Infusion of 1.2 pmol.kg-1.min-1 GLP-I with 20 g glucose (10% dextrose in water) injected intravenously over 60 min enhanced plasma responses of immunoreactive CP; the mean incremental areas under concentration curves (0-60 min) increased sixfold, but the glycemic excursion was not affected. Thus, in CP-positive IDDM, pharmacological doses of GLP-I reduce glycemic excursions after meals by a mechanism(s) not dependent on stimulation of insulin secretion, presumably involving delayed gastric emptying.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Female; Glucagon; Glucagon-Like Peptide 1; Humans; Infusions, Intravenous; Insulin; Male; Peptide Fragments; Protein Precursors | 1995 |
The Wisconsin Epidemiologic Study of Diabetic Retinopathy. XVI. The relationship of C-peptide to the incidence and progression of diabetic retinopathy.
The relationship between plasma C-peptide and the 6-year incidence and progression of diabetic retinopathy was examined in a population-based study in Wisconsin. Individuals with younger-onset (n = 548) and older-onset (n = 459) diabetes were included. C-peptide was measured by radioimmunoassay with Heding's M1230 antiserum. Retinopathy was determined from stereoscopic fundus photographs. Younger- and older-onset insulin-using individuals with undetectable or low plasma C-peptide (< 0.3 nmol/l) at baseline had the highest incidence and rates of progression of retinopathy, whereas older-onset individuals with C-peptides > 0.3 nmol/l had the lowest incidence and rates of progression of retinopathy. However, within each group (younger-onset using insulin, older-onset using insulin, and older-onset not using insulin), after we controlled for other characteristics associated with retinopathy, there was no relationship between higher levels of C-peptide at baseline and lower 6-year incidence or progression of retinopathy. These data suggest that glycemic control, and not C-peptide, is related to the incidence and progression of diabetic retinopathy. Topics: Adult; Age of Onset; Biomarkers; Blood Pressure; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Disease Progression; Female; Glycated Hemoglobin; Humans; Incidence; Insulin; Male; Obesity; Proteinuria; Wisconsin | 1995 |
Insulin secretion and glucose tolerance evolution in kidney-pancreas graft.
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Time Factors | 1995 |
Human fetal islet transplantation in IDDM patients: an 8-year experience.
Topics: Biomarkers; C-Peptide; CD4-CD8 Ratio; Diabetes Mellitus, Type 1; Fetal Tissue Transplantation; Glucagon; Glycated Hemoglobin; Graft Rejection; Humans; Insulin; Insulin Secretion; Interleukin-2; Islets of Langerhans Transplantation; Time Factors | 1995 |
Islet and kidney transplantation using ATG and cyclosporin monotherapy and a central facility for islet isolation and purification.
Topics: Adult; Antilymphocyte Serum; Blood Glucose; C-Peptide; Cell Separation; Creatinine; Cyclosporine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Middle Aged; T-Lymphocytes | 1995 |
Natural history of insulin independence after transplantation of multidonor cryopreserved pancreatic islets in type 1 diabetic humans.
Topics: Adult; Blood Glucose; C-Peptide; Cryopreservation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Tissue Donors | 1995 |
Increasing serum osteocalcin after glycemic control in diabetic men.
The pathogenesis of diabetic osteopenia is unclear. The markers of bone metabolism may show some changes in diabetic patients. In this study, we investigated the effect of glycemic control on serum osteocalcin level and urinary hydroxyproline excretion and the relations of these markers to duration of diabetes, C-peptide status, and body mass index. Twenty-seven men with poorly controlled diabetes mellitus (DM) (HbA1 > 9%, fasting plasma glucose > 7.8 mmol/liter) between ages 25 and 60 years (means +/- SD 46.6 +/- 10.4) were included in the study. Duration of diabetes was 5.8 +/- 4.7 years, body mass index (BMI) was 25 +/- 3.5 kg/m2, and fasting C-peptide was 2.33 (1.05-3.21) micrograms/liter. None of the patients had a disease or were treated with drugs that would interfere with calcium or phosphate metabolism and/or bone structure. They were free from chronic diabetic complications. Of these patients, 11 were lost to follow-up before metabolic control was achieved. The remaining 16 patients obtained good glycemic control (HbA1 < 8.3%, fasting plasma glucose < 7.8 mmol/liter) and completed the study. Serum osteocalcin level and urinary hydroxyproline excretion were determined before and after glycemic control. Urinary hydroxyproline excretion was not significantly changed by glycemic control [17.8 (7.1-23.2) versus 18.1 (10.9-28.1) mg/m2 day, P > 0.05]. However, serum osteocalcin level was significantly elevated (5.04 +/- 1.43 versus 4.17 +/- 1.83 micrograms/liter, P = 0.04). We found no correlation among fasting plasma glucose, HbA1, and fasting serum C-peptide levels with urinary hydroxyproline excretion. There was also no correlation between serum osteocalcin and fasting plasma glucose or serum C-peptide, but HbA1 was negatively correlated with serum osteocalcin (P = 0.01). No correlation was found between DM duration and BMI in the patients with serum osteocalcin level and urinary hydroxyproline excretion. To eliminate the possible effect of exogenous insulin on bone metabolism, the correlation analysis between the markers and C-peptide was further repeated in oral agents-treated patients. Serum C-peptide was not correlated to serum osteocalcin or urinary hydroxyproline in this subgroup of patients. Knowing that serum osteocalcin is a marker of bone formation, we concluded that osteoblast function may improve by glycemic control in diabetic patients; this may be due to correction of metabolic abnormalities associated with insulinopenia. Topics: Adult; Alkaline Phosphatase; Blood Glucose; C-Peptide; Calcium; Creatinine; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hydroxyproline; Longitudinal Studies; Male; Middle Aged; Osteocalcin; Phosphorus | 1995 |
Improved postprandial metabolic control after subcutaneous injection of a short-acting insulin analog in IDDM of short duration with residual pancreatic beta-cell function.
To compare postprandial metabolic control after subcutaneous injection of a short-acting insulin analog [Lys(B289),Pro(B29)] (Lispro) or human regular insulin (Humulin R U-100 [Hum-R]) in insulin-dependent diabetes mellitus (IDDM) of short duration with residual beta-cell function.. Six IDDM patients (age 25 +/- 2 years, diabetes duration 14 +/- 2 months, HbA1c 6.4 +/- 0.5%) with residual pancreatic beta-cell function (fasting plasma C-peptide 0.19 +/- 0.02 nmol/l) were studied on three different occasions. Postbreakfast plasma glucose was maintained at approximately 7.1 mmol/l by means of intravenous insulin until either 1200 when 0.1 U/kg Hum-R was injected or until 1225 when 0.1 U/kg of either Hum-R or Lispro was injected subcutaneously. Lunch (mixed meal, 692 Kcal) was served at 1230 (0 min). Six nondiabetic control subjects were also studied.. After Lispro administration, the 120-min plasma glucose decreased more (6.1 +/- 0.3 mmol/l) than after injection of Hum-R at -30 min (7.7 +/- 0.3 mmol/l) or -5 min (9.9 +/- 0.2 mmol/l). By the end of the study, plasma glucose was still lower after Lispro was injected (6.7 +/- 0.3 mmol/l) than after Hum-R was injected at -30 min (7.6 +/- 0.3 mmol/l) or -5 min (7.3 +/- 0.2 mmol/l) (P < 0.05). Two IDDM patients required glucose to prevent hypoglycemia after being injected with Lispro, but four required glucose after being injected with Hum-R at -5 min (Lispro approximately 27 mmol glucose infused between 90 and 240 min; Hum-R approximately 80 mmol between 240 and 390 min). After Lispro, plasma insulin peaked earlier (at 30 min, 342 +/- 29 pmol/l) than after Hum-R injection at -30 min (at 90 min, 198 +/- 28 pmol/l) and was superimposable on that of nondiabetic subjects. In Hum-R injected at -5 min, plasma insulin peaked later (at 120 min) and subsequently remained greater than in the two other studies.. Despite the lack of a time interval between injection and meal, Lispro controls postprandial plasma glucose concentration better than Hum-R given 30 min before meals and, to an even greater extent, better than Hum-R given 5 min before meals. In addition, Lispro minimizes the risk of postprandial hypoglycemia, thus closely mimicking the postprandial glucose homeostasis of nondiabetic subjects. IDDM patients with residual pancreatic beta-cell function are the ideal candidates for prandial use of Lispro because they can maintain near-normoglycemia longer after subcutaneous analog injection because of residual endogenous insulin secretion. Topics: 3-Hydroxybutyric Acid; Adult; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Drug Administration Schedule; Eating; Fatty Acids, Nonesterified; Female; Glucagon; Glycerol; Humans; Hydroxybutyrates; Hypoglycemia; Injections, Subcutaneous; Insulin; Insulin Lispro; Islets of Langerhans; Lactates; Male; Recombinant Proteins; Reference Values; Time Factors | 1995 |
[Immunologic and insulin secretion markers in non insulin dependent diabetic patients with secondary failure to oral hypoglycemic drugs].
The pathogenesis of secondary failure to hypoglycemic agents is heterogeneous. Some patients are true insulin dependent diabetics with a slow autoimmune disease suggested by their positive islet cell antibodies. Others, have an increased insulin resistance.. To assess the frequency of positive islet cell antibodies in diabetic patients with secondary failure to oral hypoglycemic agents.. Thirty one diabetics, 16 with recent (less than six months) secondary failure and 15 with metabolically stable non insulin dependent diabetes were studied. All patients were older than 25 years old and had a body mass index of less than 30 kg/m2. C peptide levels before and at 5, 15 and 30 min after IV glucagon, islet cell antibodies using the Poly Human IgG peroxidase method and insulin sensitivity and secretion (estimated by the Homeostasis Model Assessment) were measured.. Patients with secondary failure had lower C peptide levels, compared to subjects with stable diabetes (basal: 1.5 +/- 0.2 and 2.8 +/- 0.2 ng/ml; 5 min: 2.4 +/- 0.3 and 5.5 +/- 0.5 ng/ml; 15 min: 1.9 +/- 0.3 and 4.0 +/- 0.6 ng/ml; 30 min: 1.6 +/- 0.3 and 3.4 +/- 0.5 ng/ml). Beta cell activity was 20.6 +/- 4.3% in patients with secondary failure and 92.2 +/- 9% in stable diabetics (p < 0.01). Insulin sensitivity was similar in both groups (48.6 +/- 6 and 42.8 +/- 3.5% respectively). Three patients with secondary failure and none with stable diabetes had positive islet cell antibodies. When comparing patients with secondary failure and positive antibodies and subjects with secondary failure and negative antibodies, the former had non significantly lower age, BMI and C peptide levels.. Some diabetic patients with secondary failure have positive islet cell antibodies. They should be measured in these patients to start insulin treatment precociously. Topics: Administration, Oral; Adult; Analysis of Variance; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Treatment Outcome | 1995 |
Glycaemic control of insulin-dependent diabetes mellitus in Sudan: influence of insulin shortage.
Insulin availability and routine diabetes care were cross-sectionally investigated in 122 (M/F; 59/63) insulin-dependent diabetic patients aged 6-60 years with > or = 1 year duration using a structured questionnaire interview followed by a free conversation. Haemoglobin A1c, blood glucose, and serum lipids were measured in the fasting state to assess the metabolic control. Only 12% of the patients had acceptable glycaemic control (HbA1c < 7.5%). Increased age, shorter diabetes duration, and higher body mass index were associated with better metabolic control. Omission or reduction of the insulin dose was experienced by 51% of the patients due to insulin shortage. The interview data consistently indicated that insulin non-availability had induced poor compliance to therapy regimens and lack of motivation for optimum glycaemic control. Due to limited resources, most of the patients received insufficient diabetes care and education, leading to lower rates of clinic attendance (55%), and dietary non-compliance (78.5%). Elevated haemoglobin A1c was associated with higher fasting blood glucose levels (P < 0.001), serum triglycerides (P < 0.05), and urinary glucose (P < 0.001). Measurable fasting C-peptide was observed in 52.5% of the patients and was related to the age at diagnosis, and body mass index (P < 0.001 for both). There is a considerable potential to improve diabetes care and education practice, and if accessibility to insulin is simultaneously facilitated, the glycaemic control in Sudanese diabetic patients will improve. Topics: Adolescent; Adult; Age Factors; Blood Glucose; Body Mass Index; C-Peptide; Child; Cross-Sectional Studies; Demography; Diabetes Mellitus, Type 1; Drug Administration Schedule; Fasting; Female; Glycated Hemoglobin; Glycosuria; Humans; Insulin; Lipids; Male; Middle Aged; Regression Analysis; Socioeconomic Factors; Sudan; Surveys and Questionnaires; Triglycerides | 1995 |
Mathematical formulae for the prediction of the residual beta cell function during the first two years of disease in children and adolescents with insulin-dependent diabetes mellitus.
On the basis of a retrospective study of 71 children followed for 24 months after diagnosis of type I insulin dependent diabetes a fitted mathematical model was constructed for the prediction of the course of beta cell function from the time of diagnosis. Two equations were derived, one for the maximal basal (B-max) and the other for the maximal i.v. glucagon stimulated peak C-peptide (P-max) levels reached during the remission period. The prognostic variables selected for analysis were: peak C-peptide levels at diagnosis (Po), age sex, degree of obesity, pubertal rating, the presence of islet cell antibodies (ICA) and levels of GHb. Multivariate analysis of the data showed that Po (p = 0.0006), puberty (p = 0.041). obesity (p = 0.0021), sex (p = 0.031), ICA (p = 0.0045) and GHb(p = 0.0066) significantly contributed to the prediction formula obtained for B-max whereas the contribution of the above variables for P-max were: Po (p = 0.0019), puberty (p = 0.0187), obesity (p = 0.0058), sex (p = 0.0598), ICA (p = 0.0187) and GHb (p = 0.0027). The residuals of the observed values from the values fitted by the predicted equations served to define two separate groups demonstrating distinct differences in the natural course of beta cell function in type I diabetes. This fitted model may thus be useful in distinguishing between newly diagnosed young patients who will undergo remission, requiring lower insulin doses, and those who have little chance for remission. It might also be helpful in the selection of patients most likely to benefit from immunosuppression or modulation, to maximize the benefit to risk ratio for such patients. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Mathematics; Models, Biological; Multivariate Analysis; Prognosis; Retrospective Studies; Time Factors | 1995 |
Insulin sensitivity and negative insulin feedback after pancreas transplantation in insulin-dependent diabetic patients.
The aims of this study were to determine the change in the rate of insulin-stimulated glucose disposal (insulin sensitivity) and the ability of insulin to inhibit its own secretion in four pancreas-kidney transplant recipients with insulin-dependent diabetes mellitus. Insulin sensitivity (glucose infusion rate, GIR) was measured by a euglycemic hyperinsulinemic clamp technique before and 2, 6 and 12 months after transplantation. The GIR values in the four recipients were normalized within 2 months and remained normal for 12 months after transplantation, despite long-term steroid therapy for immunosuppression. Physiological hyperinsulinemia (50-70 microU/ml) suppressed plasma C-peptide, but its nadirs were still higher than the basal levels in normal controls. Taking into account evidence of a minimal increase in the concentration of circulating insulin that inhibits insulin secretion in healthy subjects and evidence of increased insulin secretion in pancreas recipients, the authors speculate that defective feedback inhibition of insulin secretion could contribute, at least in part, to the disproportionate basal hyperinsulinemia in patients with a denervated, transplanted pancreas in the absence of insulin resistance. Topics: Adult; Blood Glucose; C-Peptide; Case-Control Studies; Combined Modality Therapy; Diabetes Mellitus, Type 1; Evaluation Studies as Topic; Feedback; Female; Humans; Immunosuppressive Agents; Insulin; Kidney Transplantation; Pancreas Transplantation | 1995 |
Development of type II diabetes after combined kidney-pancreas transplantation in a patient with type I (insulin-dependent) diabetes.
Topics: Adult; Amylases; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Fasting; Female; Follow-Up Studies; Glucose Clamp Technique; Glycated Hemoglobin; Graft Rejection; Humans; Insulin; Insulin Antibodies; Kidney Transplantation; Pancreas Transplantation; Proinsulin; Time Factors | 1994 |
[Use of cyclosporin A for remission induction in newly-detected insulin-dependent diabetes].
It has been postulated that some of the recent-onset insulin-dependent diabetics, after the initial use of insulin therapy, might develop the "honey moon period", i.e., a spontaneous remission of the disease, defined as the state of normal metabolic control maintained without insulin therapy. However, it has also been shown that spontaneous remission appears only in 5% of the patients treated with conventional insulin therapy and lasts, most frequently, not more than a few weeks. Different therapeutic regimens of immunosuppression and immunomodulation have been used worldwide in order to induce the remission, based on the findings that an autoimmune process underlies the pathogenesis of this type of diabetes. In this study, we have shown the results of the follow-up analysis of the effects of the treatment with cyclosporin A in 21 recent-onset insulin-dependent diabetics. In 15 of those patients insulin treatment was applied as bi-daily doses of monocomponent insulin preparations, and in 6 of them intensified insulin therapy with human insulin was used. In the first group, the remission was achieved in 46.66% and in the second group in 66.66%, which is a significantly higher incidence than in control groups treated only with insulin, without cyclosporin. Moreover, the duration of remission was longer in the patients treated with cyclosporin. The analysis of the residual beta cell secretory capacity has shown that C-peptide levels (taken as a marker for insulin secretion) were slightly higher in patients with the spontaneous remission than in those with the cyclosporin-induced remission both in basal conditions and after stimulation with 1 mg of glucagon. In the patients with cyclosporin A-induced remission we found an improved basal C-peptide secretion and, even more, we detected a significant improvement in beta cell response to the glucagon stimulation. The analysis of the first-phase insulin secretory response (the insulin response to rapidly injected glucose during the intravenous glucose tolerance test) which has been shown to be impaired very early during the development of diabetes, has demonstrated the lack of its recovery both in the spontaneous and in cyclosporin A-induced remissions. The analysis of the molar insulin/C-peptide ratio has detected the impairments of this ratio which remains decreased both in spontaneous and cyclosporin-induced remissions. Topics: C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Humans; Insulin; Remission Induction | 1994 |
Islet cell antibodies (ICA), insulin autoantibodies (IAA), islet cell surface antibodies (ICSA) and C-peptide in 1031 school children in a population with a high background incidence of IDDM.
Islet cell antibodies (ICA), insulin autoantibodies (IAA) and islet cell surface antibodies (ICSA) together with C-peptide were determined in 1031 healthy schoolchildren to evaluate the frequency of autoimmune reactions towards endocrine pancreas and its relation to insulin secretion in non-diabetic children. The prevalence of ICA (levels > 6 JDF units) was 1.4% (14/1012) while 44 children (4.3%) were ICSA-positive and 40 (4%) had IAA. Girls had higher titres of ICSA than boys. Young children (7-8 years) more often had IAA than 12-13-year-old children who, however, had ICA three times more often than the young children. There were no clear associations between the different antibodies. Of the children, 2.4% had very low post-prandial serum C-peptide values (< or = 0.25 nmol/l). Serum C-peptide was higher in girls than in boys (P < 0.001) and in older children than in younger (P < 0.001). Girls with low levels of ICA had high C-peptide values, while girls with high ICA titers had low C-peptide values, the latter perhaps indicating partial beta cell loss. IAA and ICSA were not related to C-peptide values but both positive ICSA and high C-peptide values were most common in the autumn (P < 0.02 and P < 0.0001, respectively). One of the ICA-positive children developed diabetes in 1991, 4 years after the blood sample was taken. Since after 5 years only one of the children has developed IDDM, it can be concluded autoimmune reactions towards endocrine pancreas and insulin may occur in many children without the development of manifest diabetes. Those with high ICA titers may have lost so many beta cells that their insulin secretion is affected, which in some cases might lead to diabetes many years later. Topics: Adolescent; Age Factors; Autoantibodies; Autoimmune Diseases; C-Peptide; Child; Diabetes Mellitus, Type 1; Eating; Family; Female; Humans; Incidence; Insulin; Insulin Antibodies; Insulin Secretion; Islets of Langerhans; Male; Regression Analysis; Sex Characteristics; Sweden | 1994 |
[Study on structural gene expression in human insulinoma].
A human insulinoma cDNA library was constructed in the expression plasmid vector pUEX1. The clone pUEX1Ins12 was selected by means of hybridization with an insulin probe. It codes for full size amino acid sequence preproinsulin. The bacterial strain pUEX3Ins8 producing proinsulin as beta-galactosidase fusion protein was obtained for the use of recombinant protein as an antigen in an ELISA to detect serum antibodies in subjects with IDDM. Recombinant clones containing the middle, N- and C-terminal domains of the GAD65, the major autoantigen in IDDM, were constructed in pVEX1. These clones may become important tools to study the nature of GAD autoreactivity in IDDM. The clone pHICEO.9 was selected from the human insulinoma cDNA library by immunoscreening with total human insulinoma protein antibodies. This clone expresses the C-terminal fragment of human cholesterol esterase/lipase containing its antigenic determinant and can be used for blood lipase determination. Four clones containing cDNA inserts (0.47-1.42 kb) without any significant homologies to the known sequences in the Gene Bank were obtained by means of statistic selection. Topics: Amino Acid Sequence; Autoantibodies; Autoantigens; C-Peptide; Cells, Cultured; Cloning, Molecular; Diabetes Mellitus, Type 1; DNA, Complementary; Gene Expression Regulation, Neoplastic; Genes, Neoplasm; Glutamate Decarboxylase; Humans; Molecular Sequence Data; Pancreatic Neoplasms; Recombinant Proteins | 1994 |
Metabolic factors in the development of retinopathy of juvenile-onset type I diabetes mellitus.
Thirty-five patients of insulin-dependent diabetes mellitus (IDDM) were investigated for the effect of various metabolic factors on retinopathy. The severity of retinopathy increased with duration and age of onset of IDDM. Degree of glycaemia (fasting blood sugar, FBS) was similar in patients with or without retinopathy. All IDDM patients as a group showed severe carbohydrate intolerance with lower basal and post glucose serum immunoreactive insulin (IRI) levels and serum C-peptide radioimmunoreactivity (CPR) as compared to controls. The insulin secretory response was similar in no retinopathy, mild retinopathy and severe retinopathy groups. Patients with retinopathy had higher incidence of hyperlipidemia but mean serum levels of cholesterol and triglyceride were similar. This study does not suggest a direct relationship between the various metabolic factors studied and retinopathy due to IDDM. Topics: Adult; Age of Onset; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Glucose Intolerance; Humans; Hyperlipidemias; Insulin; Male; Triglycerides | 1994 |
Indications for a more aggressive disease process in newly diagnosed insulin-dependent diabetic children in northern than in southern Europe.
Finland and Sweden have the highest incidence of insulin-dependent diabetes in children in the world, about 3-4 times that of countries in the Mediterranean area, with the exception of Sardinia. We have collected information from several European clinics and from Pittsburgh, USA, in order to find out whether this difference incidence is associated with corresponding differences of the disease pattern. Patients in Finland or Sweden ('North') and Pittsburgh were younger (< 10 years old) at diagnosis compared with those in the other clinics in Europe (P < 0.05 versus P < 0.02). In the North, boys were in excess (58%) in contrast to France (40%) and Pittsburgh (46%). Patients in the North had a shorter duration of symptoms (< 8 days; P < 0.001) and higher blood glucose (> 20 mmol/l; P < 0.05) than those attending the other European clinics. Irrespective of age, there were more ICA-positive patients in the North (94%) than in Berlin-Vienna (67%; P < 0.01) or in France (70%; P < 0.01). There was a tendency for non-diabetic parents and siblings in the North to have lower C-peptide values (< 0.26 pmol/ml) at the time of diagnosis of the proband and to be ICA-positive more often than relatives in the other European clinics. The seasonal variation of diagnosis showed no obvious geographical differences, with recorded diagnosis always lowest during the summer. We conclude that certain factors seem to cause not only a high incidence of diabetes in children in Finland and Sweden but perhaps also a more aggressive early disease process. Topics: Adolescent; Adult; Age of Onset; Austria; Autoantibodies; Autoimmune Diseases; Biomarkers; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Family; Female; Finland; France; Geography; Germany; Humans; Incidence; Infant; Infant, Newborn; Islets of Langerhans; Italy; Male; Pennsylvania; Seasons; Sex Characteristics; Sweden | 1994 |
Beta cell status in infants of diabetic mothers--a pilot study.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Fetal Blood; Humans; Infant, Newborn; Insulin; Islets of Langerhans; Mothers; Pilot Projects; Pregnancy; Proinsulin; Retrospective Studies | 1994 |
Isolated hyperproinsulinaemia heralding diabetes mellitus?
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin; Proinsulin | 1994 |
Disproportionately elevated proinsulin levels precede the onset of insulin-dependent diabetes mellitus in siblings with low first phase insulin responses. The Childhood Diabetes in Finland Study Group.
The objective of this study was to test whether levels of proinsulin immunoreactivity (PIM) relative to those of insulin immunoreactivity (IRI) or C-peptide are changed and related to subclinical beta-cell dysfunction in siblings of insulin-dependent diabetes mellitus (IDDM) patients. Twenty-three siblings, previously found positive for islet cell antibodies and/or insulin autoantibodies, were divided into 2 groups according to their first phase insulin response (FPIR) to i.v. glucose tolerance tests (IVGTTs) sequentially performed during an observation period of 2 yr. Eleven siblings had diminished FPIR on at least 1 occasion (group 1), whereas 12 siblings had a normal FPIR on all occasions studied (group 2). All underwent a further IVGTT (0.5 g glucose/kg BW), and serum samples were taken at 0, 1, 3, 6, 10, 20, 30, 40, 50, and 60 min. The 2 groups had comparable median age, female/male ratio, weight, height, fasting blood glucose, immunoreactive insulin, C-peptide, and insulin autoantibodies levels, but group 1 had significantly higher islet cell antibodies levels. Fasting median PIM/IRI and PIM/C-peptide ratios were 2- to 3-fold higher in group 1 [10.5% (range, 1.8-93.8%) vs. 5.2% (range, 1.9-14.3%) and 3.3% (range, 0.4-23.1%) vs. 1.3% (range, 0.7-2.6%; P < 0.05]. Fasting PIM/C-peptide ratios correlated inversely with FPIRs (rs = -0.68; P < 0.01). During glucose stimulation, maximal responses of IRI and C-peptide were 4-fold lower in group 1, and the time of maximal responses of IRI and C-peptide occurred later in group 1 than in group 2. In contrast, no difference in maximal responses of PIM was found, but the time of maximal responses of PIM occurred later in group 1. Nine of 11 siblings in group 1 presented with IDDM 1-28 months after the test, compared to none in group 2. In group 1 a paradoxical inhibitory response of PIM was observed during the first 6 min of the IVGTT. These data indicate that fasting PIM/IRI and/or PIM/C-peptide ratio reflects subclinical beta-cell dysfunction in prediabetic subjects with evidence of immunological beta-cell assault and suggests that an elevated ratio may be an additional marker for later development of IDDM. Topics: Adolescent; Biomarkers; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fasting; Female; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Male; Proinsulin; Prospective Studies | 1994 |
Novel transplantation approach: islet cell grafts in cerebral spinal fluid shunts in dogs.
Topics: Animals; Blood Glucose; C-Peptide; Cerebrospinal Fluid Shunts; Diabetes Mellitus, Type 1; Dogs; Glucose; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Pancreatectomy; Time Factors | 1994 |
Simultaneous solid organ, bone marrow, and islet allotransplantation in type I diabetic patients.
Topics: Adult; Blood Glucose; Bone Marrow Transplantation; C-Peptide; Chimera; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Histocompatibility Testing; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Lymphocyte Activation; Male; Monitoring, Immunologic | 1994 |
Latent autoimmune diabetes mellitus in adults (LADA): the role of antibodies to glutamic acid decarboxylase in diagnosis and prediction of insulin dependency.
Type 1 diabetes mellitus in adults may present in a manner similar to that of Type 2 diabetes but with a late development of insulin dependency. We studied 65 patients who presented with 'adult-onset' diabetes after the age of 30 years. Of these patients, 19 required insulin therapy. The insulin-treated patients were significantly younger, their onset of diabetes was at an earlier age, and their postprandial serum C-peptide levels were lower than those of the non-insulin-treated group. Moreover, the insulin-treated subjects had a higher mean concentration of antibodies to glutamic acid decarboxylase (GAD) (66.8 +/- 10.2 units) than the patients who did not require insulin (9.9 +/- 1.9 units) (p < 0.001) and their frequency of anti-GAD positivity was 73.7% versus 4.3% (p < 0.001). Thus, among patients attending a diabetes clinic, the majority (73.7%) of subjects who presented with diabetes after 30 years of age and who subsequently required therapy with insulin, actually have the islet cell lesion of Type 1 diabetes which progresses at a slower tempo than in children. We conclude that testing for anti-GAD in adult-onset non-obese diabetic patients should be a routine procedure in order to detect latent insulin-dependency at the earliest possible stage, since this assay can assist in the correct classification of diabetes, and more appropriate therapy. Topics: Adult; Age of Onset; Aged; Autoantibodies; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diet, Diabetic; Female; Glutamate Decarboxylase; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Predictive Value of Tests | 1994 |
An improved method for the determination of islet amyloid polypeptide levels in plasma.
We describe an improved method for the determination of islet amyloid polypeptide (IAPP) levels in plasma. Plasma is first extracted with acid-acetone, followed by a specific and sensitive radioimmunoassay (RIA) for IAPP using rabbit-anti-human-IAPP serum. Recovery of synthetic IAPP from plasma was 82 +/- 6% (n = 16). Standard samples, prepared in 'hormone-free' serum, were also extracted with acid-acetone. Displacement curves of serially diluted acid-acetone extracted plasma samples were parallel to the standard curve. The lower detection limit of the RIA was 2.3 +/- 0.1 fmol/sample (n = 5). Intra-assay variations for IAPP concentrations of 4, 17 and 32 pM were 16.3% (n = 10), 9.2% (n = 10) and 6.2% (n = 10); interassay variations were 35.9% (n = 14), 19.9% (n = 15) and 15.4% (n = 15), respectively. Non-stimulated IAPP levels ranged from 2.4 to 12 pM (mean 6 +/- 4 pM, n = 10) in healthy control subjects. IAPP was not detectable in type 1 (insulin-dependent) diabetic patients before and after glucagon administration. In type 2 (non-insulin-dependent) diabetic patients basal levels ranged from 2.2 to 14.5 pM and glucagon-stimulated levels ranged from 2.2 to 38.9 pM. The increase in IAPP varied from 0 to 24.4 pM. The anti-human-IAPP serum had full cross-reactivity with rat IAPP (= mouse IAPP). Transgenic mice overexpressing the human IAPP gene showed elevated plasma IAPP levels as compared to (non-transgenic) control mice. It is concluded that the method presented for the determination of IAPP in plasma is reliable and easy to perform, yielding reproducible results.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Amyloid; C-Peptide; Cross Reactions; Diabetes Mellitus, Type 1; Glucagon; Humans; Injections, Intravenous; Islet Amyloid Polypeptide; Islets of Langerhans; Radioimmunoassay | 1994 |
Refractory graft duodenitis and bleeding following enteric diversion of transplanted pancreas with bladder drainage.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Duodenitis; Duodenum; Follow-Up Studies; Gastrointestinal Hemorrhage; Humans; Male; Pancreas Transplantation; Postoperative Complications; Reference Values; Reoperation; Transplantation, Homologous; Urinary Bladder | 1994 |
Evidence for different clinical subtypes of type 1 diabetes mellitus: a prospective study.
The purpose of this study was to determine whether the sex, age, severity of clinical presentation, presence of ICAs, IAs, and HLA-DR and DQ types could predict, in a cohort of newly-diagnosed diabetic children: (1) the duration of beta-cell function as measured by C-peptide response to a Sustacal meal; and (2) determine if those predictors could identify disease subtypes. A cohort of 170 consecutive patients was followed for 60 months after diagnosis. We found that age (0.0029), sex (0.0136), ICA (0.0001), presence of DKA (0.0070) and C-peptide peak at diagnosis (0.0000) significantly predicted the duration of residual beta-cell function over time. Furthermore, C-peptide secretion at diagnosis, presence of ICA, age and sex allowed the identification of three different prognostic groups with varying acceleration of beta-cell loss. Topics: Adolescent; Aging; Autoantibodies; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Humans; Infant; Islets of Langerhans; Male; Prospective Studies; Severity of Illness Index; Sex Characteristics | 1994 |
Effects of systemic delivery of insulin on plasma lipids and lipoprotein concentrations in pancreas transplant recipients.
To determine whether pancreas transplantation alters lipid and lipoprotein concentrations and whether peripheral hyperinsulinemia is always associated with altered lipid levels.. We assessed the lipid profiles of seven pancreas-kidney recipients with insulin-dependent diabetes mellitus, seven kidney recipients without diabetes who received the same immunosuppressive agents, and eight normal subjects.. In the three study groups, fasting and postprandial plasma glucose, insulin, C-peptide, cholesterol, triglyceride, free fatty acid, and apolipoprotein A-I, A-II, C-II, and C-III concentrations were determined.. Fasting and postprandial glucose concentrations did not differ between the two transplant groups; however, peripheral insulin concentrations were twice as high (P < 0.05) in the pancreas-kidney recipients as in the kidney recipients both before (102 +/- 15 versus 53 +/- 6 pmol/L) and after (123 +/- 22 versus 61 +/- 6 nmol/L per 6 hours) ingestion of a meal. Preprandial and postprandial insulin levels in both transplant groups also were greater (P < 0.05) than those in normal subjects (35 +/- 6 pmol/L and 40 +/- 7 nmol/L per 6 hours, respectively). Despite significant differences in insulin concentrations, no differences were noted in total cholesterol, high-density or low-density lipoprotein cholesterol, plasma free fatty acids, or apolipoprotein A-I, A-II, C-II, and C-III concentrations among the study groups. Plasma triglyceride concentrations in the two transplant groups were similar (114 +/- 20 versus 142 +/- 18 mg/dL) and were slightly more than those in the normal subjects (80 +/- 7 mg/dL).. Despite peripheral hyperinsulinemia, pancreas transplantation can result in normal or near-normal lipid and lipoprotein concentrations. Thus, systemic delivery of insulin does not invariably produce an atherogenic lipid profile. Topics: Adult; Apolipoproteins; Blood Glucose; C-Peptide; Case-Control Studies; Cholesterol; Diabetes Mellitus, Type 1; Eating; Fasting; Fatty Acids, Nonesterified; Female; Humans; Hyperinsulinism; Insulin; Kidney Transplantation; Male; Pancreas Transplantation; Triglycerides | 1994 |
Diminished insulin secretory reserve in diabetic pancreas transplant and nondiabetic kidney transplant recipients.
Although both kidney and pancreas transplantation can restore renal and pancreatic endocrine functions, the accompanying immunosuppression may cause diminished glucose tolerance in some individuals. Therefore, we determined to what extent pancreas transplantation itself and the triple immunosuppressive therapy used in pancreas transplant recipients have adverse effects on insulin secretory reserve. Beta-cell secretory reserve was assessed by the method of glucose potentiation of arginine-induced insulin secretion in 25 normoglycemic pancreas recipients, 12 nondiabetic kidney recipients using the same immunosuppressive therapy, 3 psoriasis patients treated long term with cyclosporine, 5 arthritis patients treated long term with prednisone, and their respective sex-, age-, and body mass index-matched control subjects. Levels of fasting glucose, HbA1c, and glucose disappearance rates were normal in all subjects. During the glucose potentiation study, pancreas recipients had significantly less insulin secretion than control subjects (maximal acute response [ARmax] = 1,083 +/- 93% vs. 3,938 +/- 355%, P < 0.001). Insulin responses were also decreased in kidney recipients (ARmax = 2,296 +/- 290%) vs. control subjects (4,691 +/- 554%, P = 0.001) and in psoriasis patients treated with cyclosporine (ARmax = 2,153 +/- 390%) vs. control subjects (3,962 +/- 88%, P = 0.011), but not as extreme as that seen in pancreas recipients. No abnormalities were observed in arthritis patients treated with steroids. We conclude that normoglycemic pancreas and kidney transplant recipients receiving triple immunosuppressive therapy have diminished beta-cell secretory reserve. Because this defect was present in psoriasis patients treated long term with cyclosporine, but not in arthritis patients treated long term with prednisone, this adverse effect was probably caused in part by cyclosporine. Topics: Adult; Arginine; Arthritis; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Immunosuppressive Agents; Insulin; Insulin Secretion; Islets of Langerhans; Kidney Transplantation; Male; Pancreas Transplantation; Prednisone; Psoriasis; Transplantation, Homologous | 1994 |
Pancreas transplantation in diabetic humans normalizes hepatic glucose production during hypoglycemia.
Although successful pancreas transplantation in humans with type I diabetes mellitus restores glucose-induced insulin secretion, provides freedom from insulin treatment, and normalizes fasting glucose levels, much less is known about its effects on counterregulation of hypoglycemia. To determine whether pancreas transplantation normalizes glucagon secretion and hepatic glucose production (HGP) during hypoglycemia, we performed hyperinsulinemic hypoglycemic clamps in successful recipients of pancreas allografts. Recipients were found to have glucagon secretory responses during hypoglycemia that were similar to those of control subjects (incremental glucagon response: recipients, 147 +/- 34 ng/L; control subjects, 161 +/- 43 ng/L, NS) but were significantly higher than those of matched subjects with type I diabetes (23 +/- 9 ng/L, P < 0.01). HGP rates at the end of 120 min of hypoglycemia were also significantly higher in recipients and control subjects than in subjects with diabetes (pancreas recipients, 1.92 +/- 0.33 mg.kg-1.min-1; control subjects, 2.05 +/- 0.18 mg.kg-1.min-1; subjects with type I diabetes, 0.58 +/- 0.12 mg.kg-1.min-1). A comparison with a third group of nondiabetic kidney transplant recipients demonstrated that the beneficial effects on glucose counterregulation were a result of pancreas transplantation and not the associated immunosuppressive therapy. We conclude that pancreas transplantation restores hypoglycemia-induced glucagon secretion and HGP, thereby allowing for normalization of glucose recovery from hypoglycemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Gluconeogenesis; Glucose; Glucose Clamp Technique; Humans; Hypoglycemia; Immunosuppressive Agents; Infusions, Intravenous; Insulin; Kidney Transplantation; Liver; Male; Pancreas Transplantation; Reference Values | 1994 |
Early changes in postprandial insulin secretion, not in insulin sensitivity, characterize juvenile obesity.
The development of hyperinsulinemia and insulin resistance, both common in adults with established obesity, was studied in 16 children, weighing 169 +/- 8% ideal body weight who were 12.7 +/- 0.4 years of age with obesity duration of 0.5-8.5 years and continuous weight gain in excess of normal, and compared with 11 age-matched normal children. Early in the evolution of obesity, insulin and C-peptide responses to a normal meal were increased by 76 and 80%. The first insulin peak was higher (613 +/- 53 pmol/ml) than normal (413 +/- 59 pmol/ml, P < 0.02) and occurred only 50 +/- 7 min after onset of lunch versus 33 +/- 11 min in normal children (P < 0.0005). Obese patients had a total of 3.0 +/- 0.2 large insulin peaks within the 6-h period after the lunch versus only 1.5 +/- 0.2 peaks in normal children (P < 0.0005). In contrast, fasting plasma insulin and C-peptide levels remained normal during the initial years of obesity, then increased progressively with duration (r = 0.73, P < 0.001) and degree (r = 0.59, P < 0.02) of obesity. Insulin sensitivity evaluated as the rate of glucose uptake during a three-step hyperinsulinemic euglycemic clamp was comparable in the obese (20 +/- 1.5 mmol.m-2.min-1) and the normal (21.7 +/- 1.5 mmol.m-2.min-1) children. Initially higher than normal in obese children, the maximal rate of glucose uptake decreased with both obesity duration (r = -0.67, P < 0.005) and children's age (r = -0.66, P < 0.005), indicating the progressive development of insulin resistance.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Analysis of Variance; Blood Glucose; Body Weight; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Eating; Female; Glucose Clamp Technique; Humans; Insulin; Insulin Secretion; Male; Obesity; Prediabetic State; Reference Values; Time Factors | 1994 |
High graft survival and excellent endocrine function after pancreas transplantation: effect of a standardized protocol.
Topics: Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Graft Survival; Humans; Insulin; Insulin Secretion; Pancreas Transplantation | 1994 |
Heterotopic pancreas transplantation does not necessarily confer basal hyperinsulinemia.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Kidney Transplantation; Pancreas Transplantation; Transplantation, Heterotopic | 1994 |
Pancreas transplantation with systemic endocrine drainage leads to improvement in lipid metabolism.
Topics: Adult; Apolipoproteins A; Apolipoproteins B; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Eating; Fasting; Fatty Acids, Nonesterified; Female; Follow-Up Studies; Humans; Immunosuppression Therapy; Insulin; Kidney Transplantation; Lipase; Lipids; Lipoprotein Lipase; Male; Pancreas Transplantation; Time Factors; Triglycerides | 1994 |
Islet Transplant Registry report on adult and fetal islet allografts.
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Fetal Tissue Transplantation; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Registries; Time Factors; Transplantation, Homologous | 1994 |
New protocol toward prevention of early human islet allograft failure.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Kidney Failure, Chronic; Kidney Transplantation; Parenteral Nutrition, Total; Prednisolone; Time Factors; Transplantation, Homologous | 1994 |
Transplantation of unpurified islets from single donors with 15-deoxyspergualin.
Topics: C-Peptide; Cell Separation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glycated Hemoglobin; Guanidines; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Time Factors | 1994 |
Pig-to-human islet transplantation in eight patients.
Topics: Animals; Antilymphocyte Serum; C-Peptide; Diabetes Mellitus, Type 1; Fetal Tissue Transplantation; Follow-Up Studies; Guanidines; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Islets of Langerhans Transplantation; Swine; Time Factors; Transplantation, Heterologous; Treatment Outcome | 1994 |
Hypoglycemia-induced autonomic failure in IDDM is specific for stimulus of hypoglycemia and is not attributable to prior autonomic activation.
We hypothesized, first, that recent antecedent hypoglycemia causes reduced autonomic responses to subsequent hypoglycemia in patients with well-controlled insulin-dependent diabetes mellitus (IDDM) and that the reduced responses are specific for the stimulus of hypoglycemia while the responses to other stimuli are unaltered and, second, that reduced autonomic responses, specifically sympathochromaffin, so-induced are not simply the result of prior activation of the system. To test the first hypothesis, eight patients with IDDM, selected for HbA1c levels < 8.0% and the absence of classic diabetic autonomic neuropathy, were studied twice. On one occasion, clamped hypoglycemia (approximately 2.8 mM) was produced at 1400-1600 on days 2 and 3; on the other occasion clamped euglycemia (approximately 5.6 mM) was produced at those times. On both occasions, autonomic responses to hypoglycemia (approximately 2.8 mM) were determined the morning of day 3 and those to standing, exercise, and a formula meal the morning of day 4. Following afternoon hypoglycemia, 1) the adrenomedullary epinephrine (EPI) response to hypoglycemia was reduced (P = 0.0397) but that to standing, exercise, and a meal were unaltered; 2) the sympathetic neural norepinephrine (NE) response to standing and to exercise was unaltered; and 3) the partially parasympathetic neural-mediated pancreatic polypeptide response to a meal was unaltered. To test the second hypothesis, seven nondiabetic subjects were studied twice, once with cycle exercise (60% peak VO2 x 60 min) and once without exercise 90 min before clamped hypoglycemia (approximately 2.8 mM). Prior exercise had no effect on the EPI, NE, or pancreatic polypeptide responses to hypoglycemia. We conclude, first, that the phenomenon of hypoglycemia-associated autonomic failure can be induced in patients with well-controlled IDDM and is specific for the stimulus of hypoglycemia and, second, that this is not simply the result of prior activation of the system. Topics: 3-Hydroxybutyric Acid; Adult; Alanine; Analysis of Variance; Autonomic Nervous System; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fasting; Fatty Acids, Nonesterified; Female; Glucagon; Glucose Clamp Technique; Growth Hormone; Heart Rate; Humans; Hydrocortisone; Hydroxybutyrates; Hypoglycemia; Insulin; Lactates; Male; Norepinephrine; Oxygen Consumption; Pancreatic Polypeptide; Physical Exertion; Posture; Reference Values; Time Factors | 1994 |
Exaggerated epinephrine response to hypoglycemia in a physically fit, well-controlled IDDM subject.
Metabolically well controlled insulin-dependent diabetic subjects (IDDM) have deficient autonomic adrenomedullary responses to hypoglycemia. This defect, coupled with the characteristic deficient glucagon response to hypoglycemia, predisposes well-controlled IDDM subjects to an increased incidence of severe hypoglycemic episodes. In this report we describe a physically trained subject with long-duration IDDM (9 years) who was rigorously well-controlled (normal HBA1c), yet had exaggerated epinephrine responses to hypoglycemia compared with normal controls. Steady state epinephrine levels during a low-dose insulin (9 pM/kg/min) hypoglycemic clamp (2.9 +/- 0.1 mM) were approximately 2-fold higher compared with normal controls (10.6 vs. 5.5 +/- 0.7 nM). Epinephrine levels during a high-dose insulin (30 pM/kg/min) hypoglycemic clamp (2.8 +/- 0.1 mM) were also increased compared with normal controls (13.1 vs. 8.8 +/- 0.6 nM). We conclude that physical training in this metabolically well-controlled IDDM subject was associated with an augmented autonomic adrenomedullary response to hypoglycemia. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Exercise; Fatty Acids, Nonesterified; Glucagon; Growth Hormone; Heart Rate; Humans; Hydrocortisone; Hydroxybutyrates; Hypoglycemia; Insulin; Lactates; Liver; Male; Pancreatic Polypeptide; Physical Fitness; Reference Values; Sports | 1994 |
C-peptide profiles in young diabetics.
Fifty-six patients who had been diagnosed diabetic prior to the age of 30 were evaluated to determine the C-peptide (CP) secretory response to a glucose load. These individuals were classified clinically as having insulin dependent (IDDM = 18); non-insulin dependent (NIDDM = 19) and insulin requiring diabetes (IRDM = 19). Insulin dependent diabetics had lower basal CP levels (0.44 +/- (SE) 0.1 ng/ml) which were not stimulated by hyperglycaemia (0.55 +/- 0.13 ng/ml) as compared to controls (basal CP = 1.6 +/- 0.2 and peak 6.2 +/- 0.8 ng/ml). Non-insulin dependent diabetics and insulin requiring diabetics could be divided broadly into two groups - one, a set of patients with low basal CP levels (NIDDM = 0.63 +/- 0.09 ng/ml) (IRDM = 0.38 +/- 0.08 ng/ml) and a blunted response to a glucose load (peak response NIDDM = 0.83 +/- 0.05 ng/ml, IRDM = 0.59 +/- 0.12 ng/ml) and a second group who had CP reserve evident in both fasting (NIDDM = 1.6 +/- 0.2 ng/ml; IRDM = 2.1 +/- 0.6) and post-glucose levels (Peak Response NIDDM = 4.6 +/- 0.4 ng/ml; IRDM = 3.0 +/- 0.6 ng/ml). Growth Hormone (GH) and cortisol levels were found to be high in patients with IDDM and IRDM with no insulin reserve and these did not suppress during the oral Glucose Tolerance Test. NIDDM patients with no insulin reserve had normal GH and high cortisol levels. It is emphasized from this study that insulin sensitivity is as important as the insulin secretory status in determining the presenting features of diabetes mellitus in the young. Topics: Adolescent; Adult; C-Peptide; Child; Developing Countries; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Tolerance Test; Humans; India; Insulin; Male | 1993 |
[Binding and degradation of 125I insulin of erythrocyte receptors--effect of physical exertion].
The rate of binding and degradation of 125I insulin by red blood cell receptors was determined in children with insulin-dependent diabetes at rest and after physical exercise of moderate intensity (35% VO2max). Anthropometric values, duration of the disease, parameters of lipid and carbohydrate metabolism as well as blood serum levels of insulin and C-peptide were used as the features characterizing the studied children. The determination of the amount of bound and degraded 125I insulin by intact erythrocytes was carried out by the modified method of Gambhir. The method of Hildebrandt was used when the analogous measurements were carried out with hemolysate as a source of receptor. It was found that physical exercise of aerobic type resulted in an increase in the amount of 125I-insulin bound to the red blood cell receptors by about 30%. This value was not statistically significant. Statistically significant differences were, however, obtained for post-exercise concentrations of insulin and C-peptide in blood serum and for the amounts of 125I-insulin degraded by intact erythrocytes and by hemolysate. The observed increase in the amount of degraded insulin may reflect an increase in the activity of insulinase, an enzyme bound to the cell membrane and partly present in the cytoplasm. Topics: Adolescent; Anthropometry; C-Peptide; Carbohydrate Metabolism; Diabetes Mellitus, Type 1; Erythrocytes; Humans; Insulin; Iodine Radioisotopes; Physical Exertion; Receptor, Insulin | 1993 |
Hormonal enteroinsular axis in newborn infants of insulin-treated diabetic mothers.
To study whether the increased glucose levels in the amniotic fluid during diabetic pregnancies induce an early maturation of the hormonal enteroinsular axis, we measured blood glucose levels and plasma concentrations of C-peptide, pancreatic glucagon, enteroglucagon, and gastric inhibitory polypeptide (GIP) in cord blood from 18 newborn infants of insulin-treated diabetic mothers (IDM) and 18 infants of nondiabetic mothers. In addition, we studied the same parameters in 20 IDM and 12 control infants before and after their first feed comprising human milk (5 mL/kg), given by nasogastric tube at the age of 2 h. The IDM had significantly higher blood glucose levels and plasma C-peptide concentrations in their cord blood than the control infants, which was followed postnatally by a substantial fall in these levels, whereas a more modest decrease could be seen in the control infants. Circulating enteroglucagon and GIP concentrations at the age of 2 h were significantly higher than those observed in cord blood in both the IDM and the control infants, but the IDM had significantly lower blood glucose levels, higher plasma C-peptide, and lower enteroglucagon concentrations before the first feed. There was a significant increase in blood glucose levels after the feed in both the IDM and the control infants, and the concentrations 2 h after feeding were of the same magnitude in the two groups. No significant C-peptide response could be observed in either group, but the IDM continuously had higher C-peptide concentrations. A significant enteroglucagon and GIP response could be seen in the IDM, whereas the controls exhibited only a GIP response. However, no significant differences were found between the two groups in the absolute postprandial plasma concentrations of these hormones. Our results show rapid, substantial postnatal changes in circulating concentrations of enteroinsular hormones in both IDM and control infants. Enteral feeding with human milk corrects early postnatal hypoglycemia within 2 h in most IDM without causing any exacerbation of their hyperinsulinemia. The absence of any C-peptide response to the first feed and of any observed differences between IDM and normal infants in absolute concentrations of enteroglucagon and GIP after the first feed suggests that the enteroinsular axis matures postnatally in both groups of infants. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Digestive System; Enteral Nutrition; Female; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptides; Humans; Infant, Newborn; Insulin; Islets of Langerhans; Male; Milk, Human; Pancreas; Pregnancy; Pregnancy in Diabetics | 1993 |
Immunogenetic and clinical characterization of slowly progressive IDDM.
To examine the clinical and immunogenetic heterogeneity of IDDM.. We divided 207 IDDM patients into groups based on the interval from clinical onset to initiation of insulin therapy: group A (< 3 mo, acute clinical-onset group, n = 134), group B (3-12 mo, intermediate group, n = 31), and group C (> or = 13 mo, slowly progressive group, n = 42). Immunogenetic and clinical markers were compared between group A and group C.. The mode age of onset was higher in group C (52 yr) than group A (10 yr). Group C had a higher prevalence of islet cell antibodies (42.9%, 18 of 42) than group A (25.4%, 34 of 134, P = 0.05). Serum C-peptide immunoreactivity assayed by radioimmunoassay in response to a 100-g oral glucose tolerance test was significantly higher in group C than in group A. Group C patients were also more likely to have a family history of NIDDM (26.1%, 11 of 42) among their first-degree relatives than group A patients (11.2%, 15 of 134, P = 0.039). The prevalences of family history of IDDM and endocrine autoimmune diseases were not different between groups C and A. The frequency of complications of endocrine autoimmune disease was not different between group A (6.7%, 9 of 134) and group C (2.3%, 1 of 42). Significant associations with two class I major histocompatibility complex antigens (HLA-A24 and -Bw54) and one class II antigen (HLA-DR4) were observed in group A. Group A patients were associated with three diabetogenic HLA-DQ haplotypes including DQA1*0301-DQB1*0401, DQA1*0301-DQB1*0302, and DQA1*0301-DQB1*0303. In contrast, group C lacked the association with class I antigens, although HLA-DR4 and HLA-DQA1*0301-DQB1*0401 were more common in this group than in control subjects.. These results indicate that the clinical subtype with slowly progressive course (slowly progressive IDDM) has distinct findings including late-age onset, high prevalence of islet cell antibodies, preserved beta-cell function, and high family history of NIDDM. An additive effect of class I and class II major histocompatibility complex antigens is suggested as an explanation for the acute clinical manifestations and more severe beta-cell destruction in group A patients. Topics: Adolescent; Adult; Autoantibodies; Base Sequence; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Gene Frequency; Glycated Hemoglobin; Haplotypes; Histocompatibility Testing; HLA-A Antigens; HLA-B Antigens; HLA-DQ Antigens; HLA-DR Antigens; Humans; Islets of Langerhans; Male; Middle Aged; Molecular Sequence Data; Oligodeoxyribonucleotides; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Reference Values | 1993 |
Association of HLA-A24 with complete beta-cell destruction in IDDM.
A sensitive C-peptide immunoreactivity radioimmunoassay demonstrated the presence of subtle, but definite residual beta-cell function in patients with IDDM of long duration. Although HLA antigens are known to influence susceptibility to IDDM, their contribution to the extent of pancreatic beta-cell destruction has not yet been examined extensively. We studied the relationship between residual beta-cell function and HLA class I and class II antigens in 111 unrelated Japanese IDDM patients. Using the sensitive C-peptide immunoreactivity radioimmunoassay, the presence or absence of residual beta-cell function was evaluated by the C-peptide immunoreactivity response to a 100-g oral glucose load. DNA typing for HLA-DQA1 and HLA-DQB1 antigens was performed in addition to serological typing of HLA-A, HLA-B, HLA-C, and HLA-DR antigens. A C-peptide immunoreactivity response > 0.033 nM was regarded as an indication of the presence of residual beta-cell function, not the assay error. Surprisingly, 35 of 37 (94.6%) patients without residual beta-cell function had HLA-A24, whereas only 39 of 74 (52.7%) patients with residual beta-cell function had this antigen (corrected P = 9.795 x 10(-6). Any other HLA antigens, including the DR and DQ loci, showed no difference in the frequency with regard to residual beta-cell function. The duration of diabetes was similar between the groups with and without residual beta-cell function.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Alleles; Base Sequence; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Histocompatibility Testing; HLA-A Antigens; HLA-A24 Antigen; HLA-DQ Antigens; Humans; Islets of Langerhans; Male; Middle Aged; Molecular Sequence Data; Oligodeoxyribonucleotides; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Radioimmunoassay; Reference Values | 1993 |
[Effects of insular hormones on the secretion of atrial natriuretic factor].
Aim of this study was to verify the existence of a correlation between the insular hormones and the atrial natriuretic factor (ANF). We studied 70 subjects (20 control, 20 obese, 20 non insulin-dependent diabetic obese, 10 insulin-dependent diabetic subjects) submitted to a glucagon test (1 mg i.v.). Blood samples were collected at -15, 0, 3, 6, 12, 15, 30, 60, 120, 150 minutes to assay insulin, C-peptide, serum electrolytes and ANF levels. The results to point out are: the ANF basal values are significantly higher (p < 0.01) in non insulin-dependent obese patients than in controls; the obese subjects also present a significant difference (p < 0.05). After glucagon injection no variations have been found in the ANF values until the 15th minute; then the controls, the obese and, above all, the non insulin-dependent diabetic obese subjects showed a significant increase of the ANF values between 60' and 90' (basal values 38 +/- 4 ng/ml; 90' values 85 +/- 7 ng ml). As these high values appear only after the induction of hyperinsulinism in our experiment and are not present in the type-1 diabetic subjects, it's probable that insulin, rather than glucagon, stimulates, directly or indirectly, the ANF secretion. If this hypothesis is confirmed, the correlation between insulin and ANF should deserve attention from a therapeutic point of view in subjects with glycometabolic imbalance. Topics: Adolescent; Adult; Atrial Natriuretic Factor; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Humans; Hyperinsulinism; Insulin; Male; Middle Aged; Obesity; Potassium; Secretory Rate; Sodium | 1993 |
The size of the pancreas in diabetes mellitus.
To determine whether there was an association between the size of the pancreas and the type of diabetes, ultrasonography of the pancreas was performed on 57 diabetic patients: 14 with Type 1 (insulin-dependent) diabetes, 10 insulin-treated and 33 tablet-treated patients with Type 2 (non-insulin-dependent) diabetes, and 19 non-diabetic subjects. The pancreas of patients with Type 1 diabetes was markedly smaller (p < 0.0001) than the pancreas in non-diabetic subjects. The pancreas of patients with Type 2 diabetes was more moderate in size: larger (p < 0.001) than that of Type 1 diabetic patients but smaller (p < 0.5) than the pancreas of the control group. Pancreatic size of patients with Type 2 diabetes was also related to basal insulin secretion with insulin-deficient patients (low or undetectable C-peptide) having smaller (p < 0.05) pancreases than those with normal insulin secretion. There was no difference in the size of the pancreas in the different treatment groups of Type 2 diabetic patients. Pancreatic size did not correlate with age, body mass index or the duration of diabetes. We conclude that the pancreas is a smaller organ in patients with diabetes mellitus and that the decrement in size is maximal in insulin-dependent/insulin-deficient subjects. Ultrasonography, therefore, can potentially serve to discriminate between the different types of diabetes. Topics: Adolescent; Adult; Aged; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Fructosamine; Hexosamines; Humans; Male; Middle Aged; Pancreas; Reference Values; Ultrasonography | 1993 |
Hepatic glucose production during intraperitoneal and intravenous closed-loop insulin regulation of blood glucose in type 1 (insulin-dependent) diabetic patients.
Intraperitoneal infusion of insulin should be more physiological than intravenous insulin since part of the insulin is directed toward the portal vein, which allows the liver to retain its major role in glucose homeostasis. The regulation of hepatic glucose production during the intraperitoneal and intravenous infusions of insulin were compared in eight Type 1 (insulin-dependent), C-peptide-deficient diabetic patients. Primed, continuous infusions of [6,6-2H]glucose were given in the postabsorptive state and during continuous infusion of unlabelled glucose at 1.5 and 4 mg/kg.min, while normoglycaemia was maintained by closed-loop intraperitoneal and intravenous insulin delivery. During all three periods, plasma glucose concentrations remained near normal (variations 3.8-6.1%). The insulin infusion rates required for normal plasma glucose concentrations were essentially the same for the intravenous and intraperitoneal routes in all cases, although the variations were greater with intraperitoneal insulin. Plasma free-insulin levels were only slightly, non-significantly lower with intraperitoneal infusion than with intravenous infusion. Hepatic glucose production was significantly lower with intraperitoneal insulin during all three conditions: basal: 1.71 +/- 0.14, i.p. vs 2.37 +/- 0.26 mg/kg.min, i.v.; 1.5 mg/kg.min glucose infusion: 0.49 +/- 0.23, i.p. vs 0.88 +/- 0.18 mg/kg.min, i.v.; 4 mg/kg.min glucose infusion: 0.31 +/- 0.10, i.p. vs 0.56 +/- 0.12 mg/kg.min, i.v.. These results, obtained with steady-state conditions for plasma glucose, isotopic plasma glucose enrichments and unlabelled glucose infusion rates, suggest that better control of hepatic glucose production leading to normoglycaemia was achieved with the intraperitoneal infusion. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Glucagon; Gluconeogenesis; Glucose; Glucose Clamp Technique; Glycerol; Growth Hormone; Homeostasis; Humans; Hydrocortisone; Hydroxybutyrates; Insulin; Insulin Infusion Systems; Liver; Male; Middle Aged | 1993 |
Lack of effect of hyperglycemia on lipolysis in humans.
To examine whether hyperglycemia is an independent regulator of adipose tissue lipolysis, we measured palmitate flux ([3H]palmitate) on two occasions in eight volunteers with insulin-dependent diabetes. On one. occasion, euglycemia was maintained for 4 h continuously; on a different occasion, hyperglycemia (plasma glucose, 12 mmol/l) was induced after 2 h of euglycemia. Palmitate flux decreased from 1.39 +/- 0.22 to 1.25 +/- 0.18 mumol.kg-1 x min-1 during sustained euglycemia and from 1.43 +/- 0.24 to 1.13 +/- 0.19 mumol.kg-1 x min-1 during the transition from the euglycemic to the hyperglycemic study intervals. There were no significant differences between the changes in palmitate flux from the first to the second study interval on the control (euglycemia-euglycemia) and experimental (euglycemia-hyperglycemia) study days and no difference between palmitate flux on different study days. Thus, in the face of euinsulinemia, euglucagonemia, and the absence of somatostatin, no effect of hyperglycemia on free fatty acid metabolism could be detected in humans. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Clamp Technique; Growth Hormone; Humans; Hyperglycemia; Insulin; Lipolysis; Male; Palmitic Acid; Palmitic Acids; Radioimmunoassay; Time Factors | 1993 |
Insulin therapy increases low plasma growth hormone binding protein in children with new-onset type 1 diabetes.
This study was undertaken (1) to evaluate growth hormone binding protein (GHBP) levels in newly diagnosed patients with Type 1 diabetes before and after insulin therapy and (2) to determine the relationship of GHBP to glycaemic control, C-peptide level and blood pH. GHBP, expressed as a percentage of (125I)GH bound, was determined in 33 patients with Type 1 diabetes (M/F = 19/14, 12.3 +/- 0.4 years) before (day 0), after 5 days (day 5) and after 3 months (month 3) of insulin therapy. At day 0, GHBP was lower in Type 1 diabetes compared with 38 matched healthy control subjects (3.9 +/- 0.4 vs 8.2 +/- 0.4%, p < 0.001). There was no significant improvement in GHBP at day 5 (4.4 +/- 0.3%). At month 3, GHBP increased to (6.0 +/- 0.4%, p < 0.001 vs day 0), but was still lower than controls, p < 0.001. At day 0 GHBP correlated with BMI (r = 0.50, p = 0.001), blood glucose (r = -0.43 p = 0.006) and pH (r = 0.48, p = 0.004), but not HbA1. GHBP at month 3 correlated with day 0 C-peptide (r = 0.41, p = 0.02). Thus, (1) circulating GHBP is low in newly diagnosed patients with Type 1 diabetes, and increases after 3 months of insulin therapy but does not normalize and (2) the severity of biochemical derangement and residual beta-cell function at diagnosis may determine GHBP status and its recovery. We conclude that insulin is an important modulator of GH binding protein in newly diagnosed children with Type 1 diabetes. Topics: Adolescent; Body Mass Index; C-Peptide; Carrier Proteins; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Growth Hormone; Humans; Insulin; Male; Puberty; Reference Values; Time Factors | 1993 |
Family stress and resources: potential areas of intervention in children recently diagnosed with diabetes.
This article examines the relationships among family stress, family capabilities, and the health status of 53 children diagnosed with insulin-dependent diabetes mellitus. Assessments were done at an outpatient diabetes clinic of family coping, resources, and stress; disease-related knowledge; metabolic control (HbA1); and endogenous insulin (C peptide). Results indicated that higher levels of family stress and lower levels of family resources as reported by fathers were significantly associated with poor metabolic control. Multiple regression analyses revealed that levels of family stress and resources were more strongly related to metabolic control than were disease variables such as C peptide levels. Moreover, family stress was directly associated with metabolic control, and family resources showed indirect linkages. Findings suggest that family stress and resources are potential areas for social work intervention in children recently diagnosed with diabetes. Topics: Adaptation, Psychological; Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Family Health; Female; Glycated Hemoglobin; Health Knowledge, Attitudes, Practice; Health Status; Humans; Male; Missouri; Social Support; Stress, Psychological | 1993 |
A prospective study identifying risk factors for discontinuance of insulin pump therapy.
To identify characteristics of adult patients at baseline associated with duration of subsequent, continuous, subcutaneous infusion of insulin treatment (pump therapy) of type I diabetes.. For 6 wk, patients followed a standardized conventional therapy and kept a record of insulin dosages, capillary blood glucose concentrations, and symptomatic hypoglycemia. They were then hospitalized. Additional baseline data were obtained and pump therapy was started. Survival analysis was used to determine the relationship between baseline independent variables or risk factors and duration of pump therapy, which is the dependent variable.. Of the 68 participants, 33 (49%) terminated pump therapy after an average of 9.9 mo of treatment. Two models (each P < 0.00005) were developed that exhibited a high degree of consistency. Of the 6 variables, 5 were common to both models (HbA1, autonomic neuropathy, mean amplitude of glycemic excursions, frequency of symptoms of hypoglycemia when blood glucose was < 70 mg/dl, and erythema at injection sites). The sixth variable in model 1 (insulin dosage) was replaced in model 2 by a variable, Adult Self-Efficacy for Diabetes, which was obtained on the 33 more recently enrolled patients; this variable related to patient perceptions of self-care behaviors.. We found that, at baseline, the presence of a high concentration of HbA1 and a low estimation by the patient of their ability to treat the disease portend failure of insulin pump therapy as evidenced by its discontinuation. This effect is accentuated when clinical evidence of autonomic neuropathy is observed. These findings offer guidance in selecting patients with type I diabetes for insulin pump therapy. Topics: Adolescent; Adult; Analysis of Variance; Blood Glucose; C-Peptide; Depression; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Neuropathies; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged; Prospective Studies; Radioimmunoassay; Risk Factors; Surveys and Questionnaires; Time Factors | 1993 |
Physiological, symptomatic and hormonal responses to acute hypoglycaemia in type 1 diabetic patients with autonomic neuropathy.
The effects of peripheral autonomic neuropathy on the symptomatic, physiological, and hormonal responses to acute insulin-induced hypoglycaemia were studied in two groups of patients with Type 1 diabetes, matched for age, duration of diabetes, and prevailing glycaemic control. A group of eight patients who gave a history of normal awareness of hypoglycaemia and had normal cardiovascular autonomic function tests were compared to a group of six patients who had symptoms of autonomic dysfunction and gross abnormalities of cardiovascular autonomic function tests. An additional two patients with autonomic neuropathy who also had hypoglycaemia unawareness were studied. Acute hypoglycaemia was induced by intravenous infusion of insulin (2.5 mU kg-1 min-1) and the onset of the acute autonomic reaction (R) was identified objectively by the sudden rise in heart rate and onset of sweating. Cognitive function and hypoglycaemia symptom scores were estimated serially, and plasma counterregulatory hormones were measured. Acute autonomic activation was observed to occur in all subjects in response to hypoglycaemia and commenced at similar venous plasma glucose concentrations in both groups (neuropathic patients: 1.6 +/- 0.2 mmol l-1 vs non-neuropathic patients 1.6 +/- 0.2 mmol l-1, p = 0.9,). In the neuropathic patients plasma adrenaline responses were significantly lower at all time points from time R until time R + 30 min (MANOVA for repeated measures, F = 19.4, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Awareness; Blood Glucose; C-Peptide; Cardiovascular System; Cognition; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Diarrhea; Epinephrine; Female; Glucagon; Glycated Hemoglobin; Heart Rate; Humans; Hypoglycemia; Hypotension, Orthostatic; Insulin; Male; Middle Aged; Pancreatic Polypeptide; Reaction Time; Sweating; Valsalva Maneuver | 1993 |
Hypersensitivity to insulin during remissions in cyclosporin-treated IDDM patients.
To test the sensitivity to insulin in recent-onset IDDM patients, its course according to treatment, and the advent of remissions.. The euglycemic hyperinsulinemic clamp was used in 54 recent-onset IDDM patients and 14 healthy control subjects. Patients were tested after 1,2, and 4 wk of treatment with either insulin or insulin plus cyclosporin A, during cyclosporin A-associated long-lasting remissions, and during relapses.. Insulin sensitivity was markedly decreased in all patients at onset. It was rapidly restored by insulin therapy, whether immunosuppression was associated with it or not. Insulin sensitivity was even higher than normal in the remission patients, who also were characterized by the reappearance of some endogenous insulin secretion and the sustained normalization of blood glucose profiles. During relapses, the deterioration of the blood glucose profiles was associated with some loss of insulin sensitivity.. Cyclosporin A-associated remissions represent an original situation that associates euglycemia with the persistence of low endogenous insulin secretion. Cyclosporin A by itself had no influence on sensitivity to insulin, but allowed the reappearance of some insulin secretory capacity that contributed, with the improvement of insulin sensitivity, to the development of the diabetes honeymoon. The secretion of endogenous insulin, although lower than normal, was sufficient to secure a high sensitivity to insulin and the maintenance of normal blood glucose profiles, presumably because of the fact that insulin was released directly into the portal vein in these conditions. This metabolic state was precarious: the optimal sensitivity to insulin disappeared in patients who relapsed. These results have important clinical consequences: the preservation of islet residual secretory capacity by the use of newer nontoxic immunosuppressive protocols, combined with a minimal supportive insulin therapy in remission patients, may prolong remissions and maintain an optimal insulin sensitivity. Topics: Adult; Analysis of Variance; Autoantibodies; Blood Glucose; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Drug Hypersensitivity; Female; Glucose Clamp Technique; Glycated Hemoglobin; HLA-DQ Antigens; HLA-DR Antigens; Humans; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Reference Values | 1993 |
Beta-cell function in relation to islet cell antibodies during the first 3 yr after clinical diagnosis of diabetes in type II diabetic patients.
To determine the effects of islet cell antibodies on beta-cell function during the first 3 yr after diagnosis in type II diabetic patients.. beta-cell function in type II diabetic patients with (n = 11, 50 +/- 5 yr of age) and without (n = 10, 52 +/- 4 yr of age) ICA was followed prospectively and compared with beta-cell function in type I adult diabetic patients (n = 17, 37 +/- 5 yr of age) and in healthy control subjects (n = 34, age 45 +/- 3 yr). beta-cell function was evaluated as fasting C-peptide, 1 + 3 min C-peptide after intravenous glucose, and delta C-peptide after glucagon.. Fasting C-peptide was equal in type II diabetic patients with ICA (0.30 +/- 0.03 nM) and type I diabetic patients (0.24 +/- 0.03 nM) at diagnosis, and decreased (P < 0.05) during 3 yr in these groups but not in type II diabetic patients without ICA. At diagnosis, type II diabetic patients with ICA showed a 1 + 3 min C-peptide (0.92 +/- 0.17 nM) lower (P < 0.001) than control subjects but higher (P < 0.05) than type I diabetic patients (0.53 +/- 0.11 nM). After 1 yr, 1 + 3 min C-peptide in type II diabetic patients with ICA had decreased (P < 0.05) to 0.18 +/- 0.11 nM and was equal to type I diabetic patients (0.38 +/- 0.10 nM). delta C-peptide after glucagon was equally impaired in type II diabetic patients with ICA (0.38 +/- 0.06 nM) and type I diabetic patients (0.35 +/- 0.11 nM) at diagnosis. After 3 yr, type II diabetic patients with ICA had fasting C-peptide of 0.09 +/- 0.04 nM, 1 + 3 min C-peptide of 0.18 +/- 0.10 nM, and delta C-peptide after glucagon of 0.20 +/- 0.09 nM, values equal to type I diabetic patients but lower (P < 0.01) than in type II diabetic patients without ICA, whose values remained unchanged; fasting C-peptide of 0.97 +/- 0.17 nM, 1 + 3 min C-peptide of 2.31 +/- 0.50 nM, and delta C-peptide after glucagon of 1.76 +/- 0.28 nM.. In patients considered type II diabetic with ICA, beta-cell function progressively decreased after diagnosis, and after 3 yr was similar to type I diabetic patients, whereas beta-cell function in type II diabetic patients without ICA was unchanged. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Follow-Up Studies; Glucagon; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Middle Aged; Reference Values; Time Factors | 1993 |
The effect of recombinant human growth hormone on regulation of growth hormone secretion and blood glucose in insulin-dependent diabetes.
GH hypersecretion in insulin-dependent diabetes (IDDM) is well documented. Although it has recently been shown that residual insulin secretion determines the magnitude of this GH hypersecretion, the underlying mechanisms of the disorder have not yet been clarified. The 24-h GH and blood glucose profiles, insulin-like growth factor I (IGF-I) concentrations and GH responses to GRF were analyzed in 21 insulin-dependent diabetics and 4 healthy subjects before and after 7 days treatment with recombinant human GH (rhGH) (4 IU given sc at 0800 h). According to C-peptide response to glucagon IDDM patients were subdivided into C-peptide negative (CpN, n = 12) patients without endogenous pancreatic beta-cell activity and C-peptide positive (CpP, (n = 9) patients with endogenous insulin secretion. No significant difference could be observed between the mean 24-h blood glucose profile before and after rhGH treatment in any treated group. Before and on rhGH treatment the highest 24-h GH values were observed in CpN patients when compared to CpP and controls. The rhGH treatment induced a similar increase in the mean 24-h GH concentrations in all groups studied which was statistically significant only in CpP diabetics. Mean pretreatment serum IGF-I concentrations were not significantly different between CpN, CpP patients and controls. The net increase in IGF-I concentrations after rhGH treatment was however, significantly lower in CpN patients than in CpP and control subjects. GRF-induced GH response before and after rhGH treatment was significantly greater in diabetics than in controls. The response of GH to GRF in CpN diabetics was however, almost unchanged after treatment whereas it became lower in CpP diabetics and controls. The dose of 4 IU of rhGH increased significantly GH levels in diabetics with preserved beta-cell function with consequent increase in IGF-I levels and attenuation of GRF induced GH response. In contrast, the same dose of rhGH failed to induce significant increase in GH levels in diabetics without residual beta-cell activity, most probably due to already high pretreatment levels. In addition, neither increase in IGF-I levels nor suppression of GH response to GRF on rhGH treatment was observed in CpN diabetics. The results are in keeping with an important role of portal insulin in GH-induced hepatic IGF-I secretion. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Growth Hormone; Growth Hormone-Releasing Hormone; Humans; Insulin-Like Growth Factor I; Male; Recombinant Proteins | 1993 |
No pharmacokinetic effect of retaining the infusion site up to four days during continuous subcutaneous insulin infusion therapy.
This study was designed to investigate whether the indwelling time of the needle during continuous subcutaneous insulin infusion (CSII) could contribute to one of the main problems with subcutaneous insulin administration, that is the day-to-day intra-patient variation in absorption. The effect on insulin kinetics after a bolus dose was investigated at different time intervals up to 4 days after insertion of an indwelling catheter in situ for CSII therapy. Nine insulin-dependent diabetic patients treated with pump (Nordisk Infuser; Velosulin 100 U ml-1) took part in the study. The evening before day 1 of the investigation a needle connected to the pump with a polyethylene catheter was inserted subcutaneously on the abdominal wall where it remained throughout the investigation. There were no significant differences in blood glucose or plasma free insulin profiles between days 1, 3, and 5. The intra-patient coefficient of variation of free insulin was 38% at basal and 19% at post-bolus state. We conclude that during CSII it is acceptable from a pharmacokinetic point of view to retain the infusion site for up to 4 days. Topics: Adult; Blood Glucose; C-Peptide; Catheters, Indwelling; Diabetes Mellitus, Type 1; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Middle Aged; Time Factors | 1993 |
Proinsulin levels in newborn siblings of type 1 (insulin-dependent) diabetic children and their mothers.
Elevated proinsulin levels have been observed in healthy first degree relatives of Type 1 (insulin-dependent) diabetic patients. This elevation could reflect a sequele after a previous attack on the beta-cells not necessarily leading to diabetes, or represent a family trait related to the development of diabetes. When cord plasma levels of proinsulin, insulin and C-peptide from 14 newborn siblings of Type 1 diabetic patients were compared with 21 newborn control siblings unrelated to diabetic subjects, no differences were observed. Neither were any differences observed between their mothers at delivery when comparing the same parameters. In cord plasma the proinsulin levels (median and range) were higher than those in plasma from 35 adult fasting women unrelated to diabetic subjects (10, 5-83 pmol/l vs 4, 2-33 pmol/l; p < 0.001) whereas the C-peptide levels (median and range) were lower (0.20, 0.11-0.56 nmol/l vs 0.37, 0.21-0.69 nmol/l; p < 0.001). No differences in insulin levels using a highly specific insulin assay were observed. The results suggest that newborn children have high proinsulin and low C-peptide levels unrelated to heredity of diabetes and that the previously described elevated proinsulin level observed in older first degree relatives of diabetic subjects occurs later in life. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gestational Age; Humans; Infant, Newborn; Insulin; Islets of Langerhans; Labor, Obstetric; Male; Mothers; Nuclear Family; Pregnancy; Proinsulin | 1993 |
Evidence for a role for insulin and growth hormone in overnight regulation of 3-hydroxybutyrate in normal and diabetic adolescents.
To determine the relative effects of growth hormone and insulin on ketogenesis during puberty.. We studied overnight changes in plasma ketones--3-hydroxybutyrate and acetoacetate--in 35 normal and 26 IDDM adolescents at different stages of puberty. The diabetic adolescents either were on their normal insulin regimen or were studied during an overnight euglycemic clamp with or without suppression of endogenous growth hormone release.. Total ketone body and 3-hydroxybutyrate concentrations in the normal adolescents rose significantly from 2000 (29 +/- 5 microM), reaching a peak at 0200 (103 +/- 16 microM, P < 0.001 vs. 2000). After a brief fall, a further rise occurred before breakfast. Fasting 3-hydroxybutyrate concentrations showed a negative correlation with fasting insulin levels (r = -0.46, P = 0.005) and decreased with advancing puberty, while insulin concentrations increased. In the diabetic patients on their usual insulin regimen, free insulin levels waned overnight, and an exaggerated rise in ketones was observed before breakfast. During the euglycemic clamp studies, ketone levels were higher than normal throughout the night. Mean overnight growth hormone and free insulin levels also were higher than in the normal control subjects. The addition of the anticholinergic drug pirenzepine reduced growth hormone secretion and obliterated the early-night peak of 3-hydroxybutyrate.. We conclude that the early-night peak of ketone concentrations is related to growth hormone release, whereas the fasting levels are largely determined by insulin concentration. Inadequate insulin delivery in the presence of the high growth hormone concentrations characteristic of diabetic adolescents could lead to rapid decompensation and ketoacidosis. Topics: 3-Hydroxybutyric Acid; Acetoacetates; Adolescent; Adult; Age Factors; C-Peptide; Child; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Growth Hormone; Humans; Hydroxybutyrates; Insulin; Ketone Bodies; Male; Pirenzepine; Puberty; Reference Values | 1993 |
Seven years of remission in a type I diabetic patient.
To analyze factors contributing to a long-term remission in a patient with type I diabetes.. The patient was treated with cyclosporin for 16 mo after a short duration of symptoms. During the 7-yr follow-up, we tracked his glycemic control, oral glucose tolerance, insulin sensitivity, endogenous insulin secretion, and beta-cell immunology. The results are compared with those of matched diabetic patients and healthy control subjects.. Insulin therapy was discontinued after 5 wk. Thereafter the patient had normal fasting and home blood glucose concentrations and near-normal HbA1c without insulin therapy for 7 yr. During this period, he maintained islet cell antibodies, although his basal and glucagon-stimulated C-peptide concentrations were normal. He participated in active physical training and had an insulin sensitivity higher than in sedentary control subjects or trained diabetic patients and equal to that in healthy athletes. His oral glucose tolerance decreased gradually and became diabetic during the last 3 yr.. In this patient, an early start of cyclosporin therapy probably contributed to the maintenance of endogenous insulin secretion, and insulin sensitivity was high because of physical training. Consequently, the patient was able to maintain normoglycemia without exogenous insulin therapy for 7 yr. Topics: Adolescent; Autoantibodies; Blood Glucose; Body Composition; C-Peptide; Cyclosporine; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucose; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Proinsulin; Remission, Spontaneous | 1993 |
Glucose profiles in children two years after the onset of type 1 diabetes.
The relationship of 24-h glucose profiles to age, haemoglobin A1c (HbA1c), and C-peptide concentration was analysed in consecutive, unselected children who had developed Type 1 diabetes 2 years earlier. Seventy-seven children in four age groups (age 2-4 years, n = 9; 5-8 years, n = 14; 9-12 years, n = 26; and 13-17 years, n = 28) were studied. Each child was hospitalized for 2 days for the investigations. Mean blood glucose concentration was 9.7 +/- 4.1 (SD) mmol l-1 in children aged 2-4 years; 10.7 +/- 4.0 mmol l-1 in those aged 5-8 years; 11.3 +/- 3.4 mmol l-1 in those aged 9-12 years; and 9.8 +/- 3.3 mmol l-1 in those aged 13-17 years. Results were > 7.0 mmol l-1 in 69% (range 56-76%) and > 10 mmol l-1 in 49% (39-57%) of the measurements. Values decreased by 30% (21-43%) between 10 pm and 3 am. The nadir of the mean profiles of the groups was always at 3 am. Glucose concentration was mmol l-1 in 25% (14-50%), < 2.5 mmol l-1 in 9.6% (0-21%), and < 2.0 mmol l-1 in 2.7% (0-4.2%) of the children at 3 am; hypoglycaemia was most common in those aged 5-8 years. Of the four profile characteristics used, mean blood glucose predicted HbA1c (R2 = 24.7%, p < 0.00005, multiple linear regression analysis), and slightly more in combination with age (R2 = 32.0%, p < 0.00005).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Age Factors; Analysis of Variance; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Follow-Up Studies; Glycated Hemoglobin; Humans; Time Factors | 1993 |
Hemostasis variables in type I diabetic patients without demonstrable vascular complications.
To determine hemostasis variables in type I diabetic patients without clinically demonstrable micro- and macroangiopathy and to relate them to glycemic control.. Fifty patients and 50 comparable control subjects were enrolled in this study. The patients were subdivided in two groups, according to their level of HbA1c (group 1, n = 30, HbA1c < or = 8%; group 2, n = 20, HbA1c > 8%). We determined the platelet count, the platelet aggregation in the spontaneous state and in the presence of ADP or collagen, beta-thromboglobulin, platelet factor 4, fibrinogen, von Willebrand factor (factors VIII:C, VIIIR:Ag, and VIIIR:VW), plasma and urinary fibrinopeptide A, euglobulin lysis time, anticoagulant proteins C and S, and plasma viscosity.. All coagulation variables were significantly higher in diabetic patients compared with control subjects. Moreover, when the patients were subdivided according to their levels of HbA1c, the hemostatic disturbances appeared significantly more pronounced in the poorly controlled than in the well-controlled subjects.. This study confirms the existence of a state of hypercoagulability in type I diabetes. This hypercoagulability may be related to poor glycemic control. Our study suggests that the hemostasis disturbances precede demonstrable vascular complications. Topics: Adenosine Diphosphate; Adult; Blood Coagulation Factors; Blood Pressure; Blood Viscosity; C-Peptide; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Collagen; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Female; Fibrinogen; Glycated Hemoglobin; Hemostasis; Humans; Male; Platelet Aggregation; Platelet Count; Reference Values; Triglycerides | 1993 |
Improvement in blunted glucagon response to insulin-induced hypoglycemia by strict glycemic control in diabetics.
To elucidate the mechanism of impaired pancreatic A cell function in hypoglycemia in diabetics, the effect of long-term strict glycemic regulations on hypoglycemia-induced glucagon secretion was studied. Firstly, the effect of plasma insulin concentrations on suppressing A cell was studied in healthy volunteers by injecting insulin at doses of 0.1 U/kg and 0.3 U/kg. With 0.3 U/kg of insulin, the rate of fall in glycemia and the nadir of blood glucose were made similar to those with 0.1 U/kg of insulin by glucose infusion with artificial endocrine pancreas. Plasma glucagon response after 0.3 U/kg of insulin was significantly suppressed as compared to that after 0.1 U/kg of insulin, demonstrating that not only hypoglycemic stimulus but also plasma insulin concentration were important determinants responsible for glucagon secretion in insulin-induced hypoglycemia. Secondly, effect of strict glycemic control was studied. Short-acting insulin at a dose of 0.1 U/kg was injected in an intravenous bolus form into 12 insulin-dependent (IDDM) and 9 non-insulin-dependent (NIDDM) diabetics before and 1-3 months after strict glycemic control with multiple insulin injections therapy. Before strict glycemic regulations in IDDM, no significant rise in plasma glucagon concentrations was observed during the insulin-induced hypoglycemia. In NIDDM, a rise in plasma glucagon concentrations was observed, though the response was delayed. After strict glycemic regulations, in patients with residual endogenous insulin secretion, the glucagon response to hypoglycemia improved considerably in IDDM and normalized in NIDDM. In IDDM and NIDDM, improvement in glucagon response to hypoglycemia related positively to daily urinary secretion rate of C-peptide.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Insulin Infusion Systems; Insulin Secretion; Male; Middle Aged; Reference Values; Time Factors | 1993 |
The prevalence of type 1 diabetes mellitus at follow-up of Swedish infants congenitally infected with cytomegalovirus.
In a Swedish prospective study of congenital cytomegalovirus (CMV) infection, 76 infants were shown to be infected among 16,474 newborns screened by virus isolation in urine. Seventy-three of the excreters were followed up and one developed Type 1 diabetes, as compared to 38 of the 19,483 children born during the same period (p = 0.14, Fisher's one-tailed test). Thus we found no evidence that the combined finding of congenital CMV infection and Type 1 diabetes mellitus was related. Topics: Autoantibodies; C-Peptide; Cytomegalovirus; Cytomegalovirus Infections; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucagon; Glucose Tolerance Test; Humans; Infant, Newborn; Islets of Langerhans; Male; Prevalence; Sweden | 1993 |
What level of HbA1c can be achieved in young diabetic patients beyond the honeymoon period?
Topics: Adolescent; Age of Onset; Biomarkers; Blood Glucose Self-Monitoring; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Male; Reference Values; Regression Analysis | 1993 |
Cooperation between parents in caring for diabetic children: relations to metabolic control and parents' field-dependence-independence.
Aspects of parental interaction were assessed in 20 families with diabetic, insulin-dependent children, using hour-long video-taped interviews, the children being in optimal (O, n = 10) or poor (P, n = 10) metabolic control and showing optimal or poor psychological adaptation. In comparison with the O-group parents, the P-group parents were less appreciative of one another, were less congruent in their attitudes to diabetes care, and appeared not to respect their childrens' independence and integrity; the mothers were discontented with the support given them by their husbands; the children assumed less responsibility for managing their diabetes and seemed less confident during the interview. The results are interpreted in light of an earlier finding that the P-group fathers are more field-dependent (FD) than their wives while the opposite is true for the O-group fathers. With reference to evidence from the cognitive style literature, we suggest that the relatively FD P-group fathers have difficulties in acting as autonomous sources of support to their wives resulting in marital discord and a delayed transition from maternal to self care in their children. Topics: Adaptation, Psychological; Adolescent; Attitude to Health; C-Peptide; Child; Diabetes Mellitus, Type 1; Fathers; Female; Glycated Hemoglobin; Humans; Interpersonal Relations; Male; Mothers; Parent-Child Relations; Parents; Socioeconomic Factors | 1993 |
Restoration of fuel homeostasis in IDDM patients during pregnancy by an open-loop insulin infusion system.
To characterize the effects of subcutaneous insulin pump therapy on the metabolic response (CHO and lipid oxidation, and nonoxidative glucose metabolism) to a glucose challenge of diabetic women at early pregnancy.. Seven nondiabetic and seven IDDM pregnant patients on insulin pump therapy were studied at the first trimester. Fuel oxidation rates were determined by indirect calorimetry, and blood levels of substrates and hormones were measured before and for 2 h after ingestion of a 50 g oral glucose load.. The increments in npRQ and CHO oxidation rates after the glucose meals in the diabetic women on insulin pump therapy were similar to those in the normal subjects. The glucose disposal data during the 2 h of the studies revealed that the amounts of oxidative and nonoxidative glucose utilization in the control subjects and in the IDDM patients on insulin pump therapy did not show significant differences.. This investigation demonstrated that the treatment of IDDM patients during early pregnancy by an open-loop insulin infusion system is sufficient to normalize their glucose-processing capability with respect to cellular oxidative and nonoxidative glucose metabolism in response to an oral glucose challenge, but some abnormalities in their blood profiles of glucose, lactate, and pyruvate persisted. Topics: Adult; Blood Glucose; C-Peptide; Calorimetry; Carbohydrate Metabolism; Diabetes Mellitus, Type 1; Energy Metabolism; Female; Glucagon; Homeostasis; Humans; Insulin; Insulin Infusion Systems; Ketone Bodies; Lactates; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, First; Pyruvates | 1993 |
Defects in quantitative and qualitative beta-cell function following successful segmental pancreas transplantation. Danish-Swedish Study Group of Metabolic Effect of Pancreas Transplantation (DSSGMEPT).
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Eating; Fasting; Glucagon; Glycated Hemoglobin; Humans; Islets of Langerhans; Kidney Transplantation; Middle Aged; Pancreas Transplantation; Reference Values; Tolbutamide | 1993 |
Simultaneous pancreatic and kidney transplantation before end-stage chronic renal failure.
Topics: Adult; Azathioprine; Blood Glucose; C-Peptide; Creatinine; Cyclosporine; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Kidney Failure, Chronic; Kidney Transplantation; Pancreas Transplantation | 1993 |
Transplantation of porcine fetal islet-like cell clusters into eight diabetic patients.
Topics: Adult; Animals; Antibody Formation; Antibody-Dependent Cell Cytotoxicity; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Tissue Transplantation; Humans; Immunoglobulin G; Islets of Langerhans Transplantation; Male; Middle Aged; Radioimmunoassay; Swine; Transplantation, Heterologous | 1993 |
Allotransplantation of fresh and cryopreserved islets in patients with type I diabetes: two-year experience.
Topics: Adult; Blood Glucose; C-Peptide; Cryopreservation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Immunosuppressive Agents; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Portal Vein; Retrospective Studies; Time Factors; Transplantation, Homologous; Treatment Failure | 1993 |
Loss of potentiating effect of hypoglycemia on the glucagon response to hyperaminoacidemia in IDDM.
IDDM subjects lose the ability to release glucagon during hypoglycemia. Because replacement of basal levels of amino acids enhances the glucagon response to hypoglycemia in healthy subjects, we tested whether raising amino acid levels during hypoglycemia could reverse the defective alpha-cell response in IDDM patients. For this purpose, 11 IDDM patients (HbA1 9.4 +/- 0.6%) and 8 healthy, nondiabetic subjects received two hypoglycemic insulin clamp studies (0.8 mU.kg-1 x min-1) in which plasma glucose was clamped at 55 mg/dl (3.08 mM) for 180 min. During one of the studies, an infusion of amino acids was superimposed between 120 and 180 min (0.3 g.kg-1 x h-1). This dose of amino acids had a small effect on plasma glucagon levels during euglycemic hyperinsulinemia that was comparable in normal and IDDM subjects. In healthy control subjects, plasma glucagon rose by 80% during the initial hypoglycemic phase of the study. The addition of amino acids produced a further sharp (200-250 ng/L, P < 0.02) rise in plasma glucagon, such a change did not occur in the absence of amino acids. In contrast, plasma glucagon in IDDM patients failed to increase during hypoglycemia alone and rose by only 40-50 ng/L (P < 0.05 vs. controls) when amino acid infusion was superimposed, even though plasma amino acid levels rose to the same extent in IDDM and control subjects. More importantly, the rise in glucagon produced by amino acids was comparable during hypoglycemic and euglycemic hyperinsulinemia in the IDDM patients, results strikingly different from those observed in nondiabetic control subjects.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Amino Acids; Amino Acids, Essential; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Clamp Technique; Humans; Hypoglycemia; Infusions, Intravenous; Insulin; Insulin Infusion Systems; Male; Reference Values | 1993 |
Growth hormone levels in patients with type 1 diabetes are age related.
Possible effects of age on the growth hormone (GH) levels in Type 1 diabetes were examined. The study was performed in 71 patients with Type 1 diabetes (40 C-peptide negative (CpN), without residual beta cell activity; 31 C-peptide positive (CpP), with preserved beta cell activity) and 11 healthy subjects. The patients and controls were divided into three age groups (A = 21-30; B = 31-40; C = 41-50 years). Blood glucose and growth hormone (GH) were measured at hourly intervals during 24 h in all subjects in hospital conditions. GH levels decreased significantly with age in patients with Type 1 diabetes (mean 24-h GH group A: 7.3 +/- 1.0, group B:5.3 +/- 0.6, group C: 3.7 +/- 0.4 mU 1(-1); A vs C: p = 0.0007; B vs C: p = 0.03). In all age groups GH levels were significantly higher in CpN than either in CpP diabetic patients or controls (group A CpN: 8.3 +/- 1.2, CpP: 4.7 +/- 1.0, controls: 2.2 +/- 0.3 mU 1(-1); p < 0.001; group B CpN: 7.3 +/- 0.8, CpP: 3.2 +/- 0.5, controls: 1.6 +/- 1.0 mU 1(-1); p < 0.0002; group C CpN: 5.2 +/- 0.5, CpP: 2.5 +/- 0.4, controls: 1.4 +/- 0.4 mU 1(-1); p < 0.001). Mean GH levels were significantly higher in C-peptide positive patients than in controls in all age groups (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Age Factors; C-Peptide; Diabetes Mellitus, Type 1; Female; Growth Hormone; Humans; Insulin; Male; Middle Aged; Reference Values | 1993 |
HLA-associated susceptibility to type 2 (non-insulin-dependent) diabetes mellitus: the Wadena City Health Study.
Epidemiologic data suggest that a parental history of Type 2 (non-insulin-dependent) diabetes mellitus increases the risk of Type 1 (insulin-dependent) diabetes in siblings of a Type 1 diabetes proband. This increase in risk is consistent with a shared genetic susceptibility between Type 1 and Type 2 diabetes. We have previously reported evidence that HLA-DR4-linked factors may represent a homogeneous subset of diabetes susceptibility. First, HLA-DR4 frequency was higher in Type 1 diabetic study subjects with a Type 2 diabetic parent than in Type 1 diabetic subjects whose parents were not diabetic. Second, a DR4-haplotype was transmitted from the Type 2 diabetic parent to the Type 1 offspring more often than expected. These data are consistent with the hypothesis that families with a Type 2 diabetic parent and Type 1 diabetic child, heavily determined by HLA-DR4 linked factors, may represent a homogeneous subset of diabetes susceptibility. In this report, we further explore the relationship between the high-risk HLA antigen (HLA-DR4) in study subjects with differing glycaemic status (National Diabetes Data Group criteria). In this community-based study, we find evidence that HLA-DR4 is increased in study subjects with Type 2 diabetes and may be a marker for Type 2 diabetes susceptibility. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Susceptibility; Female; Haplotypes; Histocompatibility Testing; HLA-DR Antigens; HLA-DR4 Antigen; Humans; Male; Middle Aged; Minnesota; Sex Factors | 1993 |
Effects of different plasma glucose concentrations on lipolytic and ketogenic responsiveness to epinephrine in type I (insulin-dependent) diabetic subjects.
The effects of two different plasma glucose concentrations (5 and 10 mmol/L) on lipolysis and ketogenesis during baseline and in response to epinephrine infusion were evaluated in insulin-dependent diabetic patients. Each insulin-dependent diabetic subject was studied during euglycemia, hyperglycemia with hypoinsulinemia, and hyperglycemia with hyperinsulinemia. Total ketone body (TKB) concentrations were significantly higher in hyperglycemic-hypoinsulinemic diabetics than in hyperglycemic-hyperinsulinemic and normoglycemic diabetics. Hyperglycemic-hyperinsulinemics had higher TKB concentrations than euglycemic diabetics. During epinephrine infusion, the ketone body rate of appearance and concentration significantly increased in all groups. Plasma FFA concentrations were significantly higher in hyperglycemic-hypoinsulinemic diabetics than in the other groups. During epinephrine infusion, the plasma FFA rate of appearance and concentration significantly increased in all groups. The apparent fraction of FFA converted to ketones was increased by epinephrine in all groups, except in hyperglycemic-hyperinsulinemic diabetics. In conclusion, this study demonstrates that although insulin alone decreases FFA and TKB concentrations, it does not affect the fraction of FFA converted to ketones. If hyperinsulinemia is superimposed on hyperglycemia, there is both a reduction of ketogenesis capacity, compared to hyperglycemia alone, and a decrease in the apparent fraction of FFA converted to ketone bodies. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Female; Glycerol; Hormones; Humans; Ketone Bodies; Kinetics; Lactates; Lactic Acid; Lipolysis; Male; Osmolar Concentration | 1993 |
Exercise tolerance is lower in type I diabetics compared with normal young men.
The present investigation was conducted to study metabolic and hormonal responses to prolonged exercise to exhaustion in insulin-dependent diabetic subjects. Sixteen healthy subjects (control) and 15 diabetics with no-insulin administration for 12 hours were studied. They were submitted to short-term exercise to exhaustion on a cycle ergometer at 55% to 60% of maximum oxygen consumption (VO2max). Exercise tolerance was significantly lower in diabetic subjects (66 +/- 6.7 v 117 +/- 9.4 minutes), and glucose concentration was significantly higher in these subjects. At exhaustion, only diabetic subjects showed a significant decrease in glycemia (142 +/- 20 v 111 +/- 16 mg/dL). Lactate concentration increased significantly during exercise up to 30 minutes, but at exhaustion only control subjects showed a reduction. No significant difference in free fatty acid (FFA) concentrations was observed between the groups during a 30-minute exercise period; however, at exhaustion levels were significantly higher in control subjects. Prolactin and C-peptide concentrations were significantly lower in diabetic subjects, whereas glucagon concentration was higher. No significant differences between the groups were observed for cortisol and growth hormone (GH) concentrations. We conclude that (1) diabetic subjects show reduced exercise tolerance when no insulin is administered for 12 hours, and (2) exercise to exhaustion reduces serum glucose concentrations in insulin-dependent diabetics. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exercise Tolerance; Fatty Acids, Nonesterified; Glycogen; Humans; Lactates; Lactic Acid; Male; Muscles; Respiration | 1993 |
Both acute and chronic near-normoglycaemia are required to improve insulin resistance in type 1 (insulin-dependent) diabetes mellitus.
To determine the impact of both short- and long-term "near-normoglycaemia" on insulin resistance in Type 1 (insulin-dependent) diabetes hepatic glucose production (mg.kg-1.min-1) and peripheral glucose utilisation ("M-value", mg.kg-1.min-1) were estimated during an euglycaemic hyperinsulinaemic clamp (10 mU.kg.min) in patients with either good (HbA1c < 5.8%, groups A and B) or poor (HbA1c > 7.5%, groups C and D) long-term metabolic control (time > 12 months) and in healthy subjects (HbA1c: 5.08 +/- 0.20%; n = 8). To this end blood glucose was stabilized at 6.7 mmol/l by overnight (t = 12 h) i.v. regular insulin in groups (n = 8 each) A (HbA1c: 5.49 +/- 0.46%) and C (HbA1c: 8.83 +/- 1.20%), while groups B (HbA1c: 5.55 +/- 0.19%) and D (HbA1c: 8.51 +/- 1.09%) were kept overnight on long-acting insulin without feed-back control of blood glucose before euglycaemic clamping. Thereby, pre-equilibration of blood glucose at 6.7 mmol/l was shown to normalize basal hepatic glucose production (A: 2.27 +/- 0.48; C 2.50 +/- 0.57 mg.kg-1.min-1) despite different HbA1c values, whereas basal hepatic glucose production stayed elevated in groups B (3.09 +/- 0.38 mg.kg-1.min-1) and D (3.21 +/- 0.58 mg.kg-1.min-1) with poor actual glycaemia (B: 10.9 +/- 4.6; D: 12.1 +/- 4.6 mmol/l).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Arginine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Liver; Male; Reference Values | 1993 |
Periprandial regulation of lipid metabolism in insulin-treated diabetes mellitus.
We have examined the regulation of lipid and glucose metabolism in the postabsorptive and postprandial states in six subjects with insulin-treated diabetes mellitus, and compared them with eight nondiabetic subjects. Blood or plasma concentrations of metabolites and fluxes across forearm and subcutaneous adipose tissue were studied after an overnight fast and for 6 hours after a mixed meal (3.1 MJ, 41% from fat). In the postabsorptive state, regulation of lipid metabolism in the two groups appeared basically similar except that a wider spread of plasma (free) insulin concentrations in the diabetic group led to a wider range of values of plasma nonesterified fatty acid (NEFA) release from adipose tissue, plasma NEFA concentrations, and blood ketone body concentrations. Extraction of ketone bodies across adipose tissue was positively correlated with arterial concentration in both groups (as it was in the forearm), confirming the ability of human adipose tissue to utilize ketone bodies. A single subcutaneous injection of insulin before the meal in the diabetic group produced a plasma free-insulin profile that was blunted and prolonged compared with the postprandial response in the control group. Postprandial forearm glucose uptake followed very closely the plasma (free) insulin concentration. Postprandial suppression of NEFA release from adipose tissue was essentially normal in the diabetic group, and the normal postprandial decrease in plasma NEFA concentrations was reproduced extremely closely. Forearm and adipose tissue blood flow did not differ between the groups.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adipose Tissue; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Fatty Acids, Nonesterified; Female; Food; Humans; Insulin; Ketone Bodies; Lipid Metabolism; Lipids; Male; Middle Aged | 1993 |
Plasma concentration of islet amyloid polypeptide in healthy children and patients with insulin-dependent diabetes mellitus.
Topics: Adolescent; Amyloid; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Islet Amyloid Polypeptide; Male | 1993 |
Insulin resistance is localized to skeletal but not heart muscle in type 1 diabetes.
To determine the tissue localization of insulin resistance in type 1 diabetic patients, whole body and regional glucose uptake rates were determined under euglycemic hyperinsulinemic conditions. Leg, arm, and heart glucose uptake rates were measured using positron emission tomography-derived 2-deoxy-2-[18F]-fluoro-D-glucose kinetics and the three-compartment model described by Sokoloff et al. (L. Sokoloff, M. Reivich, C. Kennedy, M.C. DesRosiers, C.S. Patlak, K.D. Pettigrew, O. Sakurada, and M. Shinohara. J. Neurochem. 28: 897-916, 1977) in eight type 1 diabetic patients and eight matched normal subjects. Whole body glucose uptake was quantitated by the euglycemic insulin clamp technique. Whole body glucose uptake was approximately 31% lower in the diabetic patients (P < 0.01) than in the normal subjects, thus confirming the presence of whole body insulin resistance. The rate of glucose uptake was approximately 45% lower in leg muscle when measured in the femoral region (55 +/- 7 vs. 102 +/- 13 mumol.kg muscle-1.min-1, diabetic patients vs. normal subjects, P < 0.05) and approximately 27% lower in the arm muscles (66 +/- 4 vs. 90 +/- 13 mumol.kg muscle-1.min-1, respectively, P < 0.05), whereas no difference was observed in heart glucose uptake [789 +/- 80 vs. 763 +/- 58 mumol.kg muscle-1.min-1 not significant (NS)]. Whole body glucose uptake correlated with glucose uptake in femoral (r = 0.93, P < 0.005) and arm muscles (r = 0.66, P < 0.05) but not with glucose uptake in the heart (r = 0.04, NS). We conclude that insulin resistance in type 1 diabetic patients is localized to skeletal muscle, whereas heart glucose uptake is unaffected.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Deoxyglucose; Diabetes Mellitus, Type 1; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Glucose; Glucose Clamp Technique; Glycated Hemoglobin; Heart; Humans; Infusions, Intravenous; Insulin; Insulin Resistance; Muscles; Myocardium; Organ Specificity; Reference Values; Tomography, Emission-Computed | 1993 |
Evidence that suppression of insulin secretion by insulin itself is neurally mediated.
We examined the mechanism by which an increase in blood insulin concentration inhibits insulin secretion by the pancreas. To this end, we determined plasma C-peptide concentrations during euglycemic-hyperinsulinemic (approximately 500 pmol/L) clamps in five patients with insulin-dependent diabetes mellitus (IDDM) after combined pancreas and kidney (P/K) transplantation, in five nondiabetic patients after kidney transplantation (K), and in six normal control subjects. Hyperinsulinemia decreased C-peptide concentrations in K patients (by 60%, P < .01) and controls (by 35%, P < .05), but not in P/K patients (653 +/- 115 v 702 +/- 197 pmol/L before and after 4 hours of hyperinsulinemia, respectively). The main difference between K patients and controls and P/K patients was that the pancreas in K patients and controls was innervated, whereas the transplanted pancreas of K/P patients was denervated. The data therefore suggested that the inhibition of pancreatic insulin secretion by hyperinsulinemia was neurally mediated. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Feedback; Female; Glucose Clamp Technique; Humans; Hyperinsulinism; Insulin; Insulin Secretion; Kidney Transplantation; Male; Pancreas; Pancreas Transplantation | 1993 |
Long-term reversal of diabetes by the injection of immunoprotected islets.
The intraperitoneal injection of insulin-producing islets immunoprotected by an alginate-poly(amino acid) membrane is a potential method of reversing diabetes without the need for lifelong immunosuppression. Previous attempts to demonstrate this technology in large animals have failed, preventing application in humans. We have determined that key factors responsible for these past failures include cytokine (interleukins 1 and 6 and tumor necrosis factor) stimulation by mannuronic acid monomers from alginate capsules with weak mechanical integrity, which results in fibroblast proliferation. With this insight, we formulated mechanically stable microcapsules by using alginate high in guluronic acid content and report prolonged reversal of diabetes in the spontaneous diabetic dog model by the intraperitoneal injection of encapsulated canine islet allografts. Euglycemia, independent of any exogenous insulin requirement, was noted for up to 172 days. Graft survival, evidenced by positive C-peptide release, was noted for as long as 726 days in a recipient receiving a single injection of immunoprotected islets. Histological evidence of viable islets retrieved from the peritoneal cavity 6 months posttransplant confirmed the biocompatibility and immunoprotective nature of this capsule formulation. The finding that intraperitoneal injection of alginate-immunoprotected islets, a minimally invasive surgical procedure, is effective in prolonged (> 1 year) maintenance of glycemic control, without the need for lifelong immunosuppression, may have significant implications for the future therapy of type I diabetes in humans. Topics: Alginates; Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dog Diseases; Dogs; Glucose Tolerance Test; Glycated Hemoglobin; Graft Survival; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Time Factors | 1993 |
A cross-sectional evaluation of cardiovascular risk factors in coronary heart disease associated with type 1 (insulin-dependent) diabetes mellitus.
The contribution from lipoproteins, blood pressure, albuminuria and demographic variables to coronary heart disease in 90 adult subjects with and 172 without Type 1 diabetes mellitus was examined in order to investigate whether risk factors were of equivalent importance in diabetic and non-diabetic coronary heart disease. Coronary heart disease (CHD) was present in roughly 25% of subjects in each group. In Type 1 diabetes those with CHD had significantly higher levels of systolic blood pressure, albumin excretion, serum creatinine, triglycerides, VLDL cholesterol and C-peptide, and reductions in serum concentrations of HDL and HDL2 cholesterol, in comparison to those without. However, the prevalence of smokers, and concentrations of Lp(a), ApoB and fibrinogen were comparable. Blood pressure and HDL cholesterol were higher in the CHD group with Type 1 diabetes in comparison to the nondiabetic group with CHD, although LDL concentrations and the prevalence of Lp(a) concentrations > 200 mg/l were lower. Logistic regression analysis revealed the strongest independent predictors of CHD in Type 1 diabetes were serum triglycerides, systolic blood pressure, age, serum LDL cholesterol, and the daily insulin dosage, whereas in the non-diabetic control group HDL2 cholesterol, Lp(a), ApoA1 and ApoB, total serum cholesterol and body mass index were additional predictors. CHD in Type 1 diabetes appears to be most closely associated with increasing age and levels of blood pressure and total serum lipids. Apolipoproteins and albuminuria did not seem to be important independent predictors of CHD in Type 1 diabetes, whereas the former were more clearly associated with CHD in non-diabetic controls. Topics: Adult; Albuminuria; Alcohol Drinking; Apolipoproteins A; Apolipoproteins B; Blood Glucose; Blood Pressure; C-Peptide; Cholesterol, HDL; Cholesterol, VLDL; Coronary Disease; Creatinine; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Fibrinogen; Humans; Lipoprotein(a); Lipoproteins, HDL; Lipoproteins, LDL; Middle Aged; Regression Analysis; Risk Factors; Smoking; Triglycerides | 1992 |
Antidiabetogenic effect of glucagon-like peptide-1 (7-36)amide in normal subjects and patients with diabetes mellitus.
Glucagon-like peptide-1 (7-36) amide (glucagon-like insulinotropic peptide, or GLIP) is a gastrointestinal peptide that potentiates the release of insulin in physiologic concentrations. Its effects in patients with diabetes mellitus are not known.. We compared the effect of an infusion of GLIP that raised plasma concentrations of GLIP twofold with the effect of an infusion of saline, on the meal-related release of insulin, glucagon, and somatostatin in eight normal subjects, nine obese patients with non-insulin-dependent diabetes mellitus (NIDDM), and eight patients with insulin-dependent diabetes mellitus (IDDM). The blood glucose concentrations in the patients with diabetes were controlled by a closed-loop insulin-infusion system (artificial pancreas) during the infusion of each agent, allowing measurement of the meal-related requirement for exogenous insulin. In the patients with IDDM, normoglycemic-clamp studies were performed during the infusions of GLIP and saline to determine the effect of GLIP on insulin sensitivity.. In the normal subjects, the infusion of GLIP significantly lowered the meal-related increases in the blood glucose concentration (P less than 0.01) and the plasma concentrations of insulin and glucagon (P less than 0.05 for both comparisons). The insulinogenic index (the ratio of insulin to glucose) increased almost 10-fold, indicating that GLIP had an insulinotropic effect. In the patients with NIDDM, the infusion of GLIP reduced the mean (+/- SE) calculated isoglycemic meal-related requirement for insulin from 17.4 +/- 2.8 to 2.0 +/- 0.5 U (P less than 0.001), so that the integrated area under the curve for plasma free insulin was decreased (P less than 0.05) in spite of the stimulation of insulin release. In the patients with IDDM, the GLIP infusion decreased the calculated isoglycemic meal-related insulin requirement from 9.4 +/- 1.5 to 4.7 +/- 1.4 U. The peptide decreased glucagon and somatostatin release in both groups of patients. In the normoglycemic-clamp studies in the patients with IDDM, the GLIP infusion significantly increased glucose utilization (saline vs. GLIP, 7.2 +/- 0.5 vs. 8.6 +/- 0.4 mg per kilogram of body weight per minute; P less than 0.01).. GLIP has an antidiabetogenic effect, and it may therefore be useful in the treatment of patients with NIDDM: Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Eating; Female; Glucagon; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Humans; Insulin; Insulin Infusion Systems; Insulin Secretion; Male; Middle Aged; Obesity; Peptide Fragments; Peptides; Somatostatin | 1992 |
Lack of feedback inhibition of insulin secretion in denervated human pancreas.
In this study, pancreas transplantation is used as a clinical model of pancreas denervation in humans. To assess the role of innervation on the feedback autoinhibition of insulin secretion, we studied four groups of subjects--group 1: 16 patients with combined pancreas and kidney transplantation (plasma glucose = 5.1 mM, HbA1c = 6.4%, creatinine = 86 mM); group 2: 8 patients with chronic uveitis on the same immunosuppressive therapy as transplanted patients (12 mg/day prednisone, 5 mg.kg-1.day-1 CsA); group 3: 4 uremic, nondiabetic patients in chronic hemodialysis; group 4: 7 normal, nondiabetic control subjects. The following means were used to study the groups: 1) a two-step hyperinsulinemic euglycemic clamp (insulin infusion rate = 1 mU and 5 mU.kg-1.min-1); and 2) a 0.3 mU.kg-1.min-1 hypoglycemic clamp (steady-state plasma glucose = 3.1 mM). Basal plasma-free IRI (84 +/- 6, 42 +/- 12, 72 +/- 12, and 30 +/- 6 pM in groups 1, 2, 3, and 4, respectively), basal C-peptide (0.79 +/- 0.05, 0.66 +/- 0.05, 3.04 +/- 0.20, and 0.59 +/- 0.06 nM in groups 1, 2, 3, and 4, respectively), and glucagon (105 +/- 13, 69 +/- 4, 171 +/- 10, and 71 +/- 5 pg/ml in groups 1, 2, 3, and 4, respectively) were increased in groups 1 and 3 with respect to groups 2 and 4 (P < 0.01). During euglycemic hyperinsulinemia, plasma C-peptide decreased by 45, 20, and 44% in groups 2, 3, and 4, respectively, but showed no significant change from the basal in patients with transplanted pancreases.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: 3-Hydroxybutyric Acid; Adult; Analysis of Variance; Blood Glucose; C-Peptide; Denervation; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Epinephrine; Fatty Acids, Nonesterified; Feedback; Follow-Up Studies; Glucagon; Glucose Clamp Technique; Glycated Hemoglobin; Hormones; Humans; Hydroxybutyrates; Insulin; Insulin Secretion; Kidney Transplantation; Lactates; Pancreas; Pancreas Transplantation; Pancreatic Polypeptide; Somatostatin; Uremia | 1992 |
[Blood platelet as a test system in the evaluation of neurohormonal imbalance in pregnant women with diabetes mellitus].
A study was made of platelet alpha 2- and beta 2-adrenoreceptors stimulated by adrenaline and alupent as well as of hemostatic system parameters the levels of ACTH, cortisol, glucagon and C-peptide in the blood of women with type I diabetes mellitus during pregnancy, surgical delivery, and the postoperative period. It is shown that the changes in the sensitivity of both subtypes of platelet adrenoreceptors are closely related to the activation of the stress-realizing systems and may serve as a test for estimating the intensity of neurohumoral imbalance both during pregnancy and surgical intervention. The sensitivity of platelet adrenoreceptors to agonists may be examined by a simple retention test allowing rapid information to be derived, which is of paramount importance under clinical conditions. Topics: Adrenocorticotropic Hormone; Blood Platelets; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Humans; Hydrocortisone; Metaproterenol; Pregnancy; Pregnancy in Diabetics; Receptors, Adrenergic, alpha; Receptors, Adrenergic, beta; Stimulation, Chemical | 1992 |
[Early intensification of treatment in diabetes using a combination of insulin and nicotinamide--effect on C-peptide levels and the course of the disease].
Significantly higher C-peptide levels were found in a group of 49 juvenile diabetics treated with insulin in combination with nicotinamide compared to 33 diabetics treated with insulin only. There had been no significant differences in the initial values of C-peptide between the two groups. After six weeks the mean basal values of C-peptide in the blood of nicotinamide treated diabetics reached 1.21 +/- 0.79 ng/ml compared to 0.87 +/- 0.55 ng/ml determined in the group treated with insulin only (p less than 0.05). After one year of therapy the differences remained significant (p less than 0.01). The insulin requirement was significantly lower in the nicotinamide treated group after six weeks (p less than 0.001) and the difference remained significant also after two years of nicotinamide treatment (p less than 0.02). A longer period of partial remission was recorded in the group of diabetics who were administered nicotinamide. (Tab. 4, Fig. 2, Ref. 13.) Topics: C-Peptide; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Humans; Insulin; Niacinamide | 1992 |
Insulin secretory profiles and C-peptide clearance kinetics at 6 months and 2 years after kidney-pancreas transplantation.
Glucose, insulin secretion, and insulin secretory pulses were measured by deconvolution of peripheral C-peptide concentrations in 10 IDDM recipients of a combined kidney-pancreas allograft 6 mo post-transplantation and were compared with 10 matched nondiabetic control subjects. Seven of the 10 recipients were restudied 2 yr post-transplantation. To control for immunosuppressive therapy, 6 patients with a kidney allograft also were studied. Pancreatic insulin secretion rates were evaluated over a 24-h period with three mixed meals. Six months post-transplantation, fasting (5.3 +/- 0.1 vs. 5.3 +/- 0.1 mM), average 24-h (6.0 +/- 0.1 vs. 5.7 +/- 0.1 mM), and meal-related (6.1 +/- 0.3 vs. 5.8 +/- 0.2 mM) plasma glucose levels were not different in control subjects and recipients, respectively. Total 24-h insulin secretion rates were similar between the two groups (150 +/- 15 vs. 182 +/- 24 nmol.m-2.24 h-1). However, post-transplantation, the relationship between basal and meal-stimulated insulin secretion was altered with increased basal insulin secretion (52.2 +/- 6.4 vs. 97.4 +/- 12.5 pmol.m-2.min-1, P less than 0.004) and reduced meal-related secretion. The proportion of total 24-h insulin secretion comprised by basal secretion was 44 +/- 4% in the control subjects vs. 73 +/- 5% in recipients. The number of ultradian oscillations of insulin secretion identified in each 24-h period by pulse analysis was similar in control subjects and recipients (11.9 +/- 0.9 vs. 10.4 +/- 0.5 oscillations/24 hr).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Kidney Transplantation; Kinetics; Male; Pancreas Transplantation; Time Factors | 1992 |
Clinical characteristics of IDDM in Hispanics and non-Hispanic whites. Little evidence of heterogeneity by ethnicity.
To compare the clinical characteristics of IDDM in HD and NHWD subjects in order to evaluate potential heterogeneity of IDDM by ethnicity.. HD subjects (n = 73) and NHWD subjects (n = 97) were recruited from the Colorado IDDM Registry. The registry included individuals who were Colorado residents, less than 18 yr old at diagnosis, placed on insulin within 2 wk of diagnosis, and had diabetes not secondary to other conditions. Residual beta-cell function was measured as the 1-h C-peptide response to a Sustacal challenge.. HD subjects were similar to NHWD subjects in insulin dose, HbA1, HLA-DR antigens, ICAs, and family history of IDDM. HD subjects were more likely to have a family history of NIDDM than NHWD subjects (11 vs. 3%, P = 0.03). HD girls had higher C-peptide levels (0.27 vs. 0.11 nm/L [0.83 vs. 0.33 ng/ml], P = 0.01), BMI (22.7 vs. 20.9 kg/m2 P = 0.04), subscapular skinfold thickness (18.9 vs. 15.0 mm, P = 0.04), and WHR (0.81 vs. 0.77, P = 0.03) than NHWD females. After controlling for diabetes duration, BMI, sex, and family history of NIDDM, residual beta-cell function was associated significantly with Hispanic ethnicity, although the term accounted for just 3% of the overall variability in C-peptide levels.. Little evidence of heterogeneity by ethnicity of IDDM patients in the Colorado IDDM Registry was found. Ethnic differences in C-peptide levels may be related to differences in body fat distribution in females rather than heterogeneity of the disease. Topics: Adolescent; Adult; Autoantibodies; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Hispanic or Latino; HLA-DR Antigens; Humans; Islets of Langerhans; Male; Registries; Skinfold Thickness; Socioeconomic Factors; White People | 1992 |
Successful reversal of spontaneous diabetes in dogs by intraperitoneal microencapsulated islets.
Long-term euglycemia by intraperitoneal transplantation of microencapsulated islets has not been described in the diabetic large animal model. In this study, we report the successful long-term reversal of diabetes by this method in spontaneous diabetic dogs. We have identified fundamental mechanism(s) associated with alginate-based microcapsule fibrosis, and have devised methods to ameliorate this problem. These include the use of purified alginate of low mannuronic acid content and cytokine suppression. Ten insulin-dependent, spontaneous diabetic dogs (insulin requirement 1-4 units/kg/day; absence of circulating C-peptide and diabetic K-values of 0.6 +/- 0.4) were entered into the study. Islets from mongrel donor pancreata were isolated and transplanted intraperitoneally either as free islet controls (n = 3) or as microencapsulated islet allografts (n = 7). In all seven encapsulated islet recipients, euglycemia was achieved within 24 hr (serum glucose failing from 304 +/- 117 to 116 +/- 72 mg/dl). IVGTT performed 14 days after islet transplant demonstrated normalization of K-values changing from a pretransplant level of 0.6 +/- 0.4 to 2.6 +/- 0.6. All animals receiving encapsulated islets remained euglycemic, free of the need for exogenous insulin, for a period of 63-172 days, with a median insulin-independence for 105 days. In contrast, recipients receiving free islets rejected their graft within seven days of implantation. In conclusion, this is the first report of long-term successful reversal of spontaneous diabetes in the large animal model by an intraperitoneal injection of encapsulated islets. The potential exists for this form of therapy to be explored in the treatment of type I diabetes in man. Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Dogs; Drug Compounding; Female; Glucose Tolerance Test; Graft Survival; Injections, Intraperitoneal; Islets of Langerhans Transplantation; Male; Reoperation | 1992 |
Ten years' clinical experience of fetal islet transplantation.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Fetal Tissue Transplantation; Fluorescein Angiography; Follow-Up Studies; Glycated Hemoglobin; Graft Survival; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation | 1992 |
Clinical transplantation of cryopreserved fetal pancreas tissue.
Topics: Adult; Blood Glucose; C-Peptide; Cryopreservation; Diabetes Mellitus, Type 1; Fetal Tissue Transplantation; Graft Rejection; Humans; Insulin; Liver; Male; Pancreas; Pancreas Transplantation; Transplantation, Heterotopic | 1992 |
Islet cell transplantation in induction and prolongation of insulin-dependent diabetes remission.
Topics: Abdominal Muscles; Adolescent; Adult; Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Infusion Systems; Islets of Langerhans Transplantation; Male; Rabbits; Transplantation, Heterologous; Transplantation, Heterotopic | 1992 |
Intrahepatic human islet transplantation at the University of Pittsburgh: results in 25 consecutive cases.
Topics: Abdominal Neoplasms; Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glycated Hemoglobin; Graft Rejection; Graft Survival; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Liver Cirrhosis; Liver Transplantation; Male; Middle Aged; Pancreatectomy; Transplantation, Autologous; Transplantation, Heterotopic | 1992 |
Evidence of in vivo human islet graft function despite a weak response to in vitro perifusion.
Topics: Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Graft Rejection; Graft Survival; Humans; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Liver; Perfusion; Transplantation, Heterotopic | 1992 |
The natural history of transplantation of insulin-producing pancreatic islets into type I diabetic patients.
Topics: Blood Glucose; C-Peptide; Cryopreservation; Diabetes Mellitus, Type 1; Graft Survival; Homeostasis; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Liver; Transplantation, Heterotopic | 1992 |
Renal hemodynamics and albumin excretion rate in patients with diabetes secondary to acquired pancreatic disease.
OBJECTIVE--To assess kidney function and AER in patients with PD. RESEARCH DESIGN AND METHODS--Thirty-three patients with PD (age 52 +/- 7 yr, duration of disease 11 +/- 6 yr, BMI 24 +/- 3 kg/m2) and 33 patients with IDDM were matched for sex, BMI, and duration of disease. GFR and RPF were determined by single injection of [51Cr]EDTA and [125I]hippurate. AER was measured by radioimmunoassay in a single timed overnight urine collection. RESULTS--GFR and RPF were, respectively, 113 +/- 35 and 441 +/- 145 ml.min-1.73 m2 in patients with PD and 123 +/- 30 and 549 +/- 94 (P < 0.001) in IDDM. FF was significantly higher in patients with PD (0.26 +/- 0.05 vs. 0.22 +/- 0.03; P < 0.001). Prevalence of hyperfiltration (GFR > 135 ml.min-1.1.73 m2) was similar in both groups (30% in patients with PD vs. 28% in those with IDDM). Geometric mean of urinary AER was 10.4 micrograms/min (range 1-186) in patients with PD and 11.2 (1-198) in IDDM patients. Some 30.3% of patients with PD and 18% of those with IDDM were microalbuminuric (AER > 20 micrograms/min). By multiple regression analysis, AER was significantly related to systolic (P < 0.04) and diastolic blood pressure (P < 0.01) and to BMI (P < 0.03) in patients with PD. Retinopathy was more frequent in microalbuminuric patients with PD than in those without elevated AER. CONCLUSIONS--We suggest that early renal abnormalities occur similarly in patients with PD and IDDM. Topics: Adult; Albuminuria; Body Mass Index; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glomerular Filtration Rate; Humans; Kidney; Middle Aged; Pancreatic Diseases; Regional Blood Flow; Renal Circulation | 1992 |
Fuel and fluid homeostasis during long-term exercise in healthy subjects and type I diabetic patients.
This study was designed to examine metabolic and hormonal effects of long-term exercise in healthy subjects and insulin-dependent (type I) diabetic patients.. Two studies were performed. First, 16 healthy males (32 +/- 3 yr) were studied during a semitriathlon competition (2 km swimming, 90 km biking, and 21 km running). Second, 9 type I diabetic males (41 +/- 2 yr) and 17 healthy matched control subjects were studied during a 75 km cross-country skiing race. Blood samples were taken before and immediately after exercise, and also during the ski race.. During the semitriathlon race, serum insulin, C-peptide, glucagon cortisol, growth hormone ACTH, prolactin, and plasma renin activity increased two- to ninefold, whereas serum testosterone fell. Apart from a fall in magnesium, serum electrolyte concentrations remained unchanged. Before long-term skiing, patients reduced their insulin dose by 30-40%. They were hyperglycemic during the initial part of the race, but near normoglycemic thereafter. There were large interindividual variations in the increments of counterregulatory hormones, whereas serum testosterone and luteinizing hormone fell quite uniformly. Plasma renin activity and aldosterone concentrations rose similarly in diabetic and healthy subjects, whereas the rise in antidiuretic hormone was slightly greater in diabetic patients. During the initial part of the race, serum atrial natriuretic peptide fell in both groups.. Severalfold increments in hormone concentrations contribute to the maintenance of fuel and fluid homeostasis during long-term exercise. With an appropriate adjustment of insulin dose and diet, also type I diabetic patients can participate in competitive long-term exercise. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Electrolytes; Energy Metabolism; Exercise; Glucagon; Growth Hormone; Homeostasis; Hormones; Humans; Hydrocortisone; Insulin; Male; Reference Values; Renin; Skiing; Sports; Water-Electrolyte Balance | 1992 |
[A case of IDDM in sixteenth-week pregnancy].
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Diabetic Ketoacidosis; Female; Fetal Diseases; Glucose Tolerance Test; Humans; Hydrocephalus; Pregnancy; Pregnancy Trimester, Second | 1992 |
C-peptide response to oral glucose.
Topics: Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Humans; Predictive Value of Tests | 1992 |
Quantitative analysis of islet glutamic acid decarboxylase p64 autoantibodies in insulin-dependent diabetes mellitus.
Autoantibodies against the beta-cell M(r) 64,000 protein (p64), recently identified as an isoform of glutamic acid decarboxylase (GAD), are prevalent in patients with insulin-dependent diabetes mellitus (IDDM). Dog islets were found to represent an abundant source of native p64 allowing the study of antigen-antibody interactions in IDDM. A quantitative, standardized assay for p64 antibodies based on dog islets was developed and evaluated. Utilizing dog and human islets the p64 antibodies were detected in 17/19 (89%) new onset 15-32-year-old patients, compared to 15/19 (79%) in a rat islet assay. ICA were detected in 15/19 (79%) patients and correlated with the presence of p64 antibodies (rs = 0.59, P < 0.004) but not with age at onset, sex, or C-peptide levels. Sensitivity therefore is improved with the dog islet p64 antibody assay which will allow future studies requiring native p64 antigen in larger quantities are possible based on our findings. Topics: Adolescent; Adult; Animals; Autoantibodies; Autoantigens; C-Peptide; Chemical Precipitation; Diabetes Mellitus, Type 1; Dogs; Evaluation Studies as Topic; Female; Fluorescent Antibody Technique; Glutamate Decarboxylase; Humans; Immunoassay; Islets of Langerhans; Male | 1992 |
Glucagon-glucose (GG) test for the estimation of the insulin reserve in diabetes.
The residual B-cell function was examined by means of the plasma C-peptide response 6 min after a combined injection of glucagon and glucose (GG test) or conventional glucagon test (G test) in four insulin-dependent diabetic patients (IDDM group), in 18 diabetic patients treated with insulin (Insulin group), 31 treated with oral hypoglycemic agents (SU group) and 27 treated with diet only (Diet group) and in 22 borderline cases. By GG test, 6-min C-peptide values of the IDDM group were 0.27 +/- 0.05 nM (n = 4) and were significantly lower than those of the Insulin group (0.89 +/- 0.09 nM, n = 12), the SU group (1.42 +/- 0.10 nM, n = 13), the Diet group (2.47 +/- 0.22 nM, n = 11) and the borderline cases (3.38 +/- 0.22 nM, n = 11). Patients with a 6-min C-peptide concentration below 0.75 nM by GG test appeared to be insulin-requiring patients. In the G test, plasma C-peptide concentrations at 6 min were 0.35 +/- 0.08 nM in the IDDM group (n = 2), 0.72 +/- 0.20 nM in the Insulin group (n = 7), 1.08 +/- 0.09 nM in the SU group (n = 20), 1.40 +/- 0.19 nM in the Diet group (n = 17) and 2.05 +/- 0.21 nM in the borderline cases (n = 12). Some of the Diet group patients showed extremely low C-peptide responses. When comparing the GG test and G test in individual cases, a greater C-peptide response was seen with the GG test in all cases except for IDDM patients.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diet, Diabetic; Glucagon; Glucose; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Middle Aged; Prediabetic State | 1992 |
Effects of C-peptide on blood flow, capillary diffusion capacity and glucose utilization in the exercising forearm of type 1 (insulin-dependent) diabetic patients.
Microvascular dysfunction is frequently seen in patients with Type 1 (insulin-dependent) diabetes. The present study was undertaken to examine whether skeletal muscle microcirculation in Type 1 diabetic patients is influenced by C-peptide. Forearm blood flow, capillary diffusion capacity and substrate exchange were studied during strenuous rhythmic forearm exercise on a hand ergometer. Measurements were made before and during i.v. infusion for 60 min of C-peptide or 0.9% NaCl in Type 1 diabetic patients and healthy subjects. During infusion the C-peptide levels in the diabetic patients increased from less than 0.05 nmol/l to 1.32 +/- 0.08 nmol/l. Prior to infusion forearm blood flow and capillary diffusion capacity during exercise were lower in the diabetic patients than the control subjects. During C-peptide infusion both variables increased in the diabetic patients (blood flow +27 +/- 4%, capillary diffusion capacity +52 +/- 9%) to levels similar to those in the healthy subjects, while no significant change was seen in the healthy control subjects or the diabetic patients given NaCl. Forearm uptake of oxygen and glucose in the diabetic patients increased markedly after C-peptide administration but were unchanged after NaCl infusion. Significant uptake of C-peptide to the deep forearm tissues was observed in the resting state; approximately 7 +/- 2% of the arterial C-peptide concentration was extracted by forearm tissues in diabetic patients as well as in healthy control subjects.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Capillaries; Diabetes Mellitus, Type 1; Diffusion; Forearm; Glycated Hemoglobin; Humans; Infusions, Intravenous; Lactates; Muscles; Physical Exertion; Reference Values; Regional Blood Flow; Vascular Resistance | 1992 |
Cellular and humoural autoimmunity markers in type 2 (non-insulin-dependent) diabetic patients with secondary drug failure.
In some cases patients with Type 2 (non-insulin-dependent) diabetes mellitus fail to respond to treatment with oral hypoglycaemic agents. These patients may respond in the same way as Type 1 (insulin-dependent) diabetic patients. Cellular immune aggression (defined as the capacity of peripheral mononuclear cells to inhibit stimulated insulin secretion by dispersed rat islet cells), insulin autoantibodies, C-peptide response and HLA antigens were determined in 31 Type 2 diabetic patients with secondary failure to oral hypoglycaemic agents and in 22 control subjects. Nine (29.03%) of the 31 Type 2 diabetic patients showed positive cellular immune aggression (2 SD below control group) and 22 (70.97%) presented no cellular immune aggression. There was a relationship between positive cellular immune aggression and each of the following parameters: age, body mass index and microangiopathy. No correlation was found between positive cellular immune aggression and glycaemia, HbA1, blood lipids or atherosclerosis. Patients with positive cellular immune aggression showed a significantly lower glucagon-stimulated C-peptide response vs those with no cellular immune aggression. Within a sub-group of patients who had never been treated with insulin, insulin autoantibodies were present in four of six patients with positive cellular immune aggression. DR2 antigen was found with decreased frequency in patients whereas no DR3/DR4 heterozygotes were observed. Our data support the hypothesis that a group of Type 2 diabetic patients with secondary failure to oral hypoglycaemic agents presented autoimmunity towards pancreatic Beta cells. Topics: Analysis of Variance; Animals; Antibody Formation; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; HLA Antigens; HLA-DQ Antigens; HLA-DR Antigens; Humans; Hypoglycemic Agents; Immunity, Cellular; Insulin; Insulin Antibodies; Insulin Secretion; Islets of Langerhans; Lymphocytes; Male; Middle Aged; Rats; Reference Values; Treatment Failure | 1992 |
Glycemic control and peripheral nerve conduction in children and young adults after 5-6 mo of IDDM. Wisconsin Diabetes Registry.
A cohort of people (n = 86) was examined in the first few months after insulin-dependent diabetes mellitus (IDDM) diagnosis to evaluate the effect of hyperglycemia on nerve conduction velocities and latencies.. Unselected cases with IDDM, who were 6-29 yr of age, were identified at diagnosis from a large, geographically defined area of southern Wisconsin. Peripheral nerve conduction was measured on a sample from this cohort.. Peroneal nerve conduction velocity was significantly inversely related to glycosylated hemoglobin (P less than 0.05, age and height adjusted). All other nerve conduction velocities and latencies (median motor, median sensory, and sural) showed the same tendency, but the associations were not statistically significant. Twenty-four-hour urine C-peptide and duration of diabetes (3-11 mo) were not consistently related to nerve conduction parameters after controlling for age and height.. These findings suggest that as early as 5-6 mo after diabetes diagnosis, and at a time frequently characterized by partial remission of IDDM, hyperglycemia has a role in the acute slowing of nerve conduction velocity. Other factors such as residual endogenous insulin production do not appear to influence these early changes. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Motor Neurons; Neural Conduction; Neurons, Afferent; Peroneal Nerve; Sural Nerve; Time Factors | 1992 |
The density, contour, and thickness of the pancreas in diabetics: CT findings in 57 patients.
Insulin has a trophic effect on pancreatic acinar tissue, so the pancreas might be expected to atrophy in persons who have diabetes. Accordingly, we analyzed the density, contour (smooth or lobulated), and thickness of the pancreas on CT scans of diabetic patients and compared the results with those in control subjects. The prevalence of pancreatic lobulation (incisurae deeper than 2 mm) and its correlation with age in diabetic and control subjects were determined. The thickness of the pancreas was measured at three levels (head, body, tail). Three groups of diabetic patients were examined: 20 insulin-dependent patients, 25 patients not treated with nor dependent on insulin, and 12 patients treated with but not dependent on insulin. A control group included 57 nondiabetic patients. The ages of the control subjects were similar to those of the diabetic patients. The statistical significance of the differences between groups of diabetic patients and control subjects was estimated by using Student's t test for the values of density and thickness and the chi 2-test for the prevalence of pancreatic lobulation. The density of the pancreas in diabetic patients and control subjects was not statistically different. Diabetic patients had increased lobulation of the pancreas. All parts of the pancreas tended to be smaller in diabetic patients, but the degree of reduction varied. It was modest in the patients not treated with insulin, pronounced in insulin-dependent patients, and intermediate in non-insulin-dependent, insulin-treated patients. Moreover, the size of the body was significantly reduced in all three groups, whereas the size of the pancreatic head was preserved in patients not treated with insulin. In conclusion, CT of the pancreas shows that although density in diabetic patients is normal, lobulation is increased. Reduction in size involves the body of the pancreas more than other parts of the gland and is more pronounced in insulin-treated diabetic patients. CT of the pancreas might be useful to predict which diabetic patients will require insulin therapy. Topics: Adult; Aged; Aged, 80 and over; Aging; Atrophy; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Pancreas; Pancreatic Diseases; Reference Values; Tomography, X-Ray Computed | 1992 |
Homogeneity in pattern of decline of beta-cell function in IDDM. Prospective study of 204 consecutive cases followed for 7.4 yr.
To study the natural history of beta-cell function from onset of IDDM to expected deterioration of insulin (C-peptide) secretion and to identify different patterns of decline, if any.. A cohort of 204 consecutive newly diagnosed IDDM (clinical criteria) patients were followed prospectively for 7.4 yr (range 6-9 yr), measuring fasting C-peptide at onset, 1, 3, 6, 9, 12, and then every 6 mo until 106 wk (range 104-135 wk). Then, postprandial C-peptide was measured.. Fasting C-peptide was 0.17 nM (range 0.11-0.25 nM) at onset followed by an annual increase rate of 0.16 nM/yr (range 0.06-0.48 nM/yr) to a peak of 0.28 nM (range 0.23-0.34 nM/yr) after 25 wk (range 12-39 wk). The subsequent annual decline rate of fasting C-peptide was 0.08 (0.05-0.12) and of postprandial C-peptide 0.03 nM/yr (range 0.02-0.06 nM/yr). None of these parameters showed bimodality in their distribution. However, some parameters were important. In men, fasting C-peptide at onset was lower, but the initial C-peptide increase rate was more pronounced compared to women. Furthermore, insulin-free remission was related to higher C-peptide levels throughout the study. C-peptide was higher during the 1st yr of diabetes in subjects greater than 30 yr of age at onset compared with younger diabetic patients. Stepwise multiple regression analysis showed that age, male sex, and fasting C-peptide at onset were of some predictive value for the C-peptide levels at 5 yr. However, simple group comparisons revealed no significant differences.. No major heterogeneity exists in the pattern of decline of beta-cell function in IDDM, although small differences in pattern could be identified in both sexes, in different age-groups, and in relation to achieving insulin-free remission. Topics: Adult; Age Factors; Body Mass Index; C-Peptide; Cohort Studies; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Prospective Studies; Regression Analysis; Sex Characteristics | 1992 |
Glycemic control in early IDDM. The Wisconsin Diabetes Registry.
A cohort (n = 277) was followed from diabetes diagnosis to evaluate longitudinal glycemic control, urinary C-peptide levels, and certain features of diabetes self-management.. Unselected cases with IDDM, who were less than 30 yr of age, were identified at diagnosis from a 28-county area in Wisconsin. Subjects were asked to submit blood every 4 mo for GHb testing, to report aspects of diabetes self-management every 6 mo, and to collect a 24-h urine specimen 4 mo after diagnosis.. In the 1st yr of diabetes, the rate of increase (0.23%/mo) in GHb was significant for the cohort (P less than 0.001) and for almost all age and sex subgroups. In the 2nd yr, there was no significant rate of increase for the cohort as a whole (P greater than 0.10). Adolescent males (10-19 yr of age) had a mean GHb level for year 2 higher than males of other age-groups and higher than female adolescents (P less than 0.001). Adolescent males had a significant rate of increase in GHb for year 2 (P = 0.02), unlike all other age and sex subgroups. Adolescents had higher initial 24-h urine C-peptide levels than children less than 10 yr of age (P less than 0.01). During the 2nd yr of diabetes, the percentage of adolescent males reporting three or more insulin injections/day was lower than any other subgroup.. These data-suggest that glycemic control stabilizes during the 2nd yr of IDDM, except in adolescent males, and that this may be due partly to aspects of self-management. Topics: Adolescent; Adult; Age Factors; Blood Glucose; C-Peptide; Child; Child, Preschool; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infant; Longitudinal Studies; Male; Self Care; Sex Characteristics | 1992 |
Factors predicting course of beta-cell function in IDDM.
The purpose of this study was to determine whether the severity o clinical presentation, sex, age, HLA type, and the presence of IAs and ICAs could predict the variation of residual insulin secretion as measured by the serum C-peptide response to a Sustacal meal.. A cohort of 151 newly diagnosed IDDM children (mean age 10.2 +/- 4.6 yr) was followed prospectively for 3 yr. Thirty-five patients (12 males, 23 females) were still secreting C-peptide after 36 mo.. We found that age (P = 0.0001), sex (P = 0.003), presence of ICA (P = 0.006), severity of clinical presentation (P = 0.001), and symptom duration (P = 0.002) significantly predicted the rate of loss of C-peptide secretion. The risks of accelerated C-peptide disappearance decreased with increasing age, the risk ratios being 0.25 for the older group (greater than 12 yr) compared with the younger group (less than 6 yr) and 0.50 for the intermediate group (6-12 yr) compared with the younger group. The risk for the presence of ICA was 1.7, and the risk for males was 1.7 also. There was a significant negative correlation between ICA titers and C-peptide at 18 and 24 mo after diagnosis (P = 0.04). There were no significant differences in HbA1 values between patients who secreted C-peptide and those who did not.. We conclude that younger age of onset, male sex, high titers of ICA, severe clinical presentation, and shorter symptom duration significantly predict accelerated rates of loss of C-peptide secretion. Topics: Age Factors; Autoantibodies; C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; HLA Antigens; Humans; Islets of Langerhans; Longitudinal Studies; Male; Prospective Studies; Sex Characteristics; Time Factors | 1992 |
Autoantibodies to 64,000-M(r) islet cell protein in long-term type 1 (insulin-dependent) diabetic patients.
Autoantibodies to the 64,000-M(r) (64K) islet cell protein, identified as glutamic acid decarboxylase, were assayed in 46 Type 1 (insulin-dependent) diabetic patients with a disease duration of more than 5 years. Of 46 Type 1 diabetic patients, 18 (39.1%) were found to be positive for 64K antibodies and 12 of these patients had been diagnosed with autoimmune thyroid disease. Serum C-peptide levels were not detectable in 15 of 18 patients positive for 64K antibodies. The samples were also tested for titres of islet cell antibodies. Islet cell antibodies were detected in 15 (32.6%) of the 46 patients and all the islet cell antibody positive patients were also found to be positive for 64K antibodies. Furthermore, of these 15 patients 12 had previously been diagnosed with autoimmune thyroid disease. A correlation between levels of 64K antibodies and islet cell antibody titre revealed that higher levels of 64K antibodies were observed in patients who had higher islet cell antibody titre. These results demonstrate that most long-term Type 1 diabetic patients with 64K antibodies were also positive for islet cell antibodies complicated by autoimmune thyroid disease. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Glutamate Decarboxylase; Graves Disease; Humans; Islets of Langerhans; Male; Molecular Weight; Thyroid Function Tests; Thyroiditis, Autoimmune | 1992 |
The effect of the somatostatin analogue octreotide on growth hormone secretion in insulin-dependent diabetics without residual insulin secretion.
Growth hormone (GH) hypersecretion is well documented in insulin-dependent diabetes mellitus (IDDM). Somatostatin inhibits GH in acromegalics and healthy subjects although data on its inhibitory effects on high GH levels in IDDM patients are controversial. The effect of treatment with the somatostatin analogue octreotide ("Sandostatin") on GH secretion, IGF1 levels and metabolic control was investigated in insulin-dependent diabetics. Growth hormone and blood glucose were measured at hourly intervals whilst IGF-I was measured every 6 hours during the 24-h period before and after 7 days' treatment with octreotide (200 micrograms subcutaneously three times daily) in 10 C-peptide negative diabetics. Octreotide significantly reduced mean 24 h GH profile (7.2 +/- 0.7 mU/L before; 5.2 +/- 0.5 mU/L on octreotide, p less than 0.01), IGF-I levels (0.62 +/- 0.06 before; 0.47 +/- 0.05 on octreotide, p less than 0.005) mean 24 h blood glucose (14.4 +/- 0.5 mmol/L before; 12.6 +/- 0.4 mmol/L on octreotide, p less than 0.001) and daily insulin requirements (44.8 +/- 3.0 IU before; 37.2 +/- 3.0 IU on octreotide, p less than 0.02). The shape of 24 h GH profile curve changed significantly on octreotide treatment (p less than 0.05) when it consisted of three nadirs and three peaks closely linked with the time of octreotide administration. Moderate (abdominal discomfort) to severe hypoglycaemia) transient side effects have been observed in all treated patients. The results of this study showed that short-term treatment with octreotide given s. c. every eight hours modulates the pattern of GH secretion in C-peptide negative insulin-dependent patients.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Growth Hormone; Humans; Insulin; Insulin Secretion; Insulin-Like Growth Factor I; Octreotide | 1992 |
Islet amyloid polypeptide (IAPP) secretion from islet cells and its plasma concentration in patients with non-insulin-dependent diabetes mellitus.
Islet amyloid polypeptide (IAPP/Amylin) is a novel peptide which was extracted from islet amyloid deposits in patients with non-insulin-dependent diabetes mellitus (NIDDM). However, its pattern of secretions and plasma concentrations under various conditions has not yet been made clear enough. In this study, we examined IAPP secretion from islet beta-cells in vitro using cultured islet cells of neonatal rat pancreas and plasma IAPP responses under various conditions in vivo in normal control subjects and patients with glucose intolerance. Our data revealed that (1) IAPP is co-secreted with insulin from islet cells of the rat pancreas by glucose and non-glucose stimuli; (2) fasting plasma IAPP levels in normal control subjects are 24.9 +/- 2.0 pg/ml and the molar ratio of IAPP/insulin is approximately 1/7; (3) fasting IAPP levels are high in obese patients and low in insulin-dependent diabetic patients, and the molar ratio of IAPP/C-peptide in NIDDM patients is lower than that in normal control subjects, suggesting the basal hyposecretion of IAPP relative to insulin in NIDDM; and (4) the obese patients who had a hyperresponsiveness of insulin relative to C-peptide had the hyperresponsiveness of IAPP relative to C-peptide during an oral glucose load, suggesting that IAPP may have some physiological effect in glucose metabolism. Topics: Adult; Amyloid; Animals; Animals, Newborn; Blood Glucose; C-Peptide; Cells, Cultured; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Clamp Technique; Glucose Tolerance Test; Humans; Insulin; Islet Amyloid Polypeptide; Islets of Langerhans; Middle Aged; Obesity; Rats; Reference Values | 1992 |
Long-term follow-up after transplantation of insulin-producing pancreatic islets into patients with type 1 (insulin-dependent) diabetes mellitus.
Purified human islets and a kidney from the same donor were transplanted into four patients with Type 1 (insulin-dependent) diabetes mellitus. Two of the patients received additional islets that were isolated from multiple donors, cryopreserved, and stored in a tissue bank. The islets were embolized into the liver via the portal vein. Immunosuppression was induced with antilymphocyte globulin and maintained with azathioprine, prednisone and cyclosporine. In the first two patients, fasting serum C-peptide rose to levels of 0.5-2.0 ng/ml during the first 4-8 weeks and mixed meal feeding elicited increases to 2-3 ng/ml. C-peptide secretion persisted for 8 months, but at progressively lower levels and insulin therapy could not be withdrawn. In the next two patients who received cryopreserved islets in addition to fresh islets, serum C-peptide levels (fasting/post-meal) rose to 4-7 ng/ml and serum glucose was more stable, allowing withdrawal of insulin therapy after 69 days in one patient, and reduced insulin doses in the other. The insulin-independent patient has maintained normal fasting glucose, glycosylated haemoglobin, and oral glucose tolerance at 1 year following cessation of daily insulin therapy. Episodes of renal graft rejection occurred in three patients, including the insulin-independent patient. High-dose steroid therapy reversed the rejection in all instances, with apparent preservation of C-peptide secretion. These data show that transplantation of purified freshly-prepared and cryopreserved islets into Type 1 diabetic patients results in prolonged insulin secretion, and that sufficient function could be provided in one patient to sustain euglycaemia in the absence of insulin therapy at 1 year of follow-up. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucose Tolerance Test; Histocompatibility Testing; Humans; Immunosuppressive Agents; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Kidney Transplantation; Male; Time Factors | 1992 |
The influence of human C-peptide on renal function and glucose utilization in type 1 (insulin-dependent) diabetic patients.
The possible influence of C-peptide administration on renal function and whole body glucose utilization was examined in 11 patients (Group 1) with Type 1 (insulin-dependent) diabetes mellitus. They were given an i.v. insulin infusion during the night before the study and were euglycaemic at the time of examination. The glomerular filtration rate and effective renal plasma flow were measured by clearance techniques using constant-rate infusions of inulin and sodium para-aminohippurate. After baseline measurements C-peptide was infused during two periods of 60 min at rates of 5 and 30 pmol.kg-1.min-1. In a control study 0.9% NaCl was infused during two 60 min periods in ten Type 1 diabetic patients (Group 2). Glomerular filtration rate decreased by 7% (p less than 0.001), effective renal plasma flow increased by 3%, (p less than 0.05) and whole-body glucose utilization rose by approximately 25% (p less than 0.05) above basal during low-dose C-peptide infusion. Group 2 showed an unaltered glomerular filtration rate, effective renal plasma flow and glucose utilization during 60 min of NaCl infusion. The differences between Group 1 and Group 2 in glomerular filtration rate and glucose utilization were statistically significant. It is concluded that short-term administration of C-peptide in physiological amounts to patients with Type 1 diabetes may reduce the glomerular filtration rate and increase whole-body glucose utilization. The results suggest the possibility that short-term C-peptide administration may exert a regulatory influence on renal function and stimulate glucose utilization in Type 1 diabetic patients. Topics: Adult; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glomerular Filtration Rate; Glucose; Glucose Clamp Technique; Glycated Hemoglobin; Humans; Infusions, Intravenous; Insulin; Kinetics; Male; p-Aminohippuric Acid; Renal Circulation; Time Factors | 1992 |
The effects of different plasma insulin concentrations on lipolytic and ketogenic responses to epinephrine in normal and type 1 (insulin-dependent) diabetic humans.
This study was performed to verify: (1) the ability of different insulin concentrations to restrict the lipolytic and ketogenic responses to exogenous epinephrine administration; (2) whether the ability of insulin to suppress the lipolytic and ketogenic responses during epinephrine administration is impaired in Type 1 (insulin-dependent) diabetic patients. Each subject was infused on separate occasions with insulin at rates of 0.2, 0.4, and 0.8 mU.kg-1.min-1 while normoglycaemic. To avoid indirect adrenergic effects on endocrine pancreas secretions, the so-called "islet clamp" technique was used. Rates of appearance of palmitic acid, acetoacetate, and 3-hydroxybutyrate were simultaneously measured with an infusion of 13C-labelled homologous tracers. After a baseline observation period epinephrine was exogenously administered at a rate of 16 ng.kg-1.min-1. At low insulin levels (20 microU/ml) the lipolytic response of comparable magnitude was detected in normal and Type 1 diabetic patients. However, the ketogenic response was significantly higher in Type 1 diabetic patients. During epinephrine administration, similar plasma glucose increments were observed in the two groups (from 4.74 +/- 0.53 to 7.16 +/- 0.77 mmol/l (p less than 0.05) in Type 1 diabetic patients and from 4.94 +/- 0.20 to 7.11 +/- 0.38 mmol/l (p less than 0.05) in normal subjects, respectively). At intermediate insulin levels (35 microU/ml) no significant differences were found between Type 1 diabetic patients and normal subjects, whereas plasma glucose levels rose from 4.98 +/- 0.30 to 6.27 +/- 0.66 mmol/l (p less than 0.05) in Type 1 diabetic patients, and from 5.05 +/- 0.13 to 6.61 +/- 0.22 mmol/l (p less than 0.05) in normal subjects. At high insulin levels (70 microU/ml) the lipolytic response was detectable only in Type 1 diabetic patients; the ketogenic response was reduced in both groups. During the third clamp, a significant rise in plasma glucose concentration during epinephrine infusion was observed in both groups. In conclusion this study shows that at low insulin levels Type 1 diabetic patients show an increased ketogenic response to epinephrine, despite their normal nonesterified fatty acid response. Instead, high insulin levels are able to restrict the ketogenic response to epinephrine in both normal and Type 1 diabetic subjects, although there is a still detectable lipolytic response in the latter. In the presence of plasma free insulin levels that completely restrict the k Topics: Acetoacetates; Adult; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Female; Glycated Hemoglobin; Heart Rate; Humans; Infusions, Intravenous; Insulin; Ketone Bodies; Kinetics; Lipolysis; Male; Palmitic Acid; Palmitic Acids; Reference Values | 1992 |
The ketosis-resistance in fibro-calculous-pancreatic-diabetes. 1. Clinical observations and endocrine-metabolic measurements during oral glucose tolerance test.
We measured circulating levels of C-peptide, pancreatic glucagon, cortisol, growth hormone and metabolites (glucose, non-esterified fatty acids, glycerol and 3-hydroxybutyrate) in fibro-calculous-pancreatic diabetic (FCPD, n = 28), insulin-dependent diabetic (IDDM, n = 28) and non-diabetic control (n = 27) subjects during an oral glucose tolerance test. There was no difference in the two diabetic groups in age (FCPD 24 +/- 2, IDDM 21 +/- 2 years, mean +/- SEM), BMI (FCPD 16.0 +/- 0.6, IDDM 15.7 +/- 0.4 kg/m2), triceps skinfold thickness (FCPD 8 +/- 1, IDDM 7 +/- 1 mm), glycaemic status (fasting plasma glucose, FCPD 12.5 +/- 1.5, IDDM 14.5 +/- 1.2 mmol/l), fasting plasma C-peptide (FCPD 0.13 +/- 0.03, IDDM 0.08 +/- 0.01 nmol/l), peak plasma C-peptide during OGTT (FCPD 0.36 +/- 0.10, IDDM 0.08 +/- 0.03 nmol/l) and fasting plasma glucagon (FCPD 35 +/- 4, IDDM 37 +/- 4 ng/l). FCPD patients, however, showed lower circulating concentrations of non-esterified fatty acids (0.73 +/- 0.11 mmol/l), glycerol (0.11 +/- 0.02 mmol/l) and 3-hydroxybutyrate (0.15 +/- 0.03 mmol/l) compared to IDDM patients (1.13 +/- 0.14, 0.25 +/- 0.05 and 0.29 +/- 0.08 mmol/l, respectively). This could be due to enhanced sensitivity of adipose tissue lipolysis to the suppressive action of circulating insulin and possibly also to insensitivity of hepatic ketogenesis to glucagon. Our results also demonstrate preservation of alpha-cell function in FCPD patients when beta-cell function is severely diminished, suggesting a more selective beta-cell dysfunction or destruction than hitherto believed. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glucose Tolerance Test; Glycerol; Growth Hormone; Humans; Hydrocortisone; Hydroxybutyrates; Male; Multivariate Analysis; Pancreas; Reference Values; Triglycerides | 1992 |
Transplantation of porcine fetal islet-like cell clusters to three diabetic patients.
Topics: Adult; Alanine Transaminase; Animals; Aspartate Aminotransferases; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Tissue Transplantation; Fibrinogen; Humans; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Platelet Count; Swine; Transplantation, Heterologous | 1992 |
C-peptide response to oral glucose and its clinical role in elderly people.
C-Peptide response to oral glucose was measured in 45 elderly diabetics, in whom final treatment was established on clinical grounds during a 16-18 months follow-up. The diabetic patients comprised 19 ultimately classified as insulin-dependent (IDD) (group 1) and 26 regarded as non-insulin-dependent (NIDD) (group 2). Fifteen matched controls (group 3) and 15 young controls (group 4) were similarly studied. Fasting C-peptide values were lower in groups 1 and 2 (1.48 +/- 0.39 and 2.14 +/- 0.22 ng/ml; mean +/- SEM, respectively) compared with groups 3 and 4 (2.51 +/- 0.16 and 2.71 +/- 0.20 ng/ml, respectively) (p less than 0.001). Peak C-peptide levels were reached at 30 min in healthy young and at 60 min in healthy elderly. All non-diabetic control subjects showed a peak of at least 6.5 ng/ml and an increment of at least 4 ng/ml. The ratio of C-peptide increment/blood glucose increment (100 delta CP/delta BG) at 60 min derived to assess beta-cell function was at least 90 in all healthy subjects. The ratio was less than 10 in 68% of IDD but in only 27% of NIDD patients (p less than 0.01). The 100 delta CP/delta BG was inversely related to the prevailing fasting blood glucose (FBG) (p less than 0.001). These findings suggest that C-peptide response to oral glucose may be a useful test in certain elderly diabetic patients whose insulin dependence is in question. Topics: Aged; Aged, 80 and over; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Islets of Langerhans; Male | 1992 |
Glucose tolerance and insulin response in parents of patients with insulin-dependent and juvenile-onset non-insulin-dependent diabetes mellitus.
Glucose tolerance and insulin response were examined using a 100 g oral glucose tolerance test (OGTT) in 108 parents of 23 patients with insulin-dependent (IDDM) and 31 patients with non-insulin-dependent diabetes mellitus (NIDDM), whose age of onset of diabetes was less than 35 years. Thirty-two age-matched healthy volunteers without a family history of diabetes were also examined as a control group. Diabetes and impaired glucose tolerance (IGT) were significantly more frequent in parents of NIDDM (diabetes 34%, IGT 27%) than in parents of IDDM (diabetes 7%, IGT 13%) (P less than 0.001). At least one parent had diabetes or IGT in 30% of IDDM and 84% of NIDDM patients (P less than 0.001), and both parents had diabetes or IGT in 9% of IDDM and 39% of NIDDM patients (P less than 0.02). Even in cases with 'normal' glucose tolerance, the mean plasma glucose was higher in parents of NIDDM than in control subjects, suggesting a high prevalence of abnormal glucose tolerance including the marginal degree of abnormality in the families of NIDDM. The early phase insulin response was decreased more among parents of NIDDM with the greater impairment of glucose tolerance. However, among those with 'normal' glucose tolerance, early phase insulin response did not differ between parents of IDDM and NIDDM, and control subjects. The results confirmed a stronger familial background in NIDDM patients of younger onset than in IDDM. The different patterns of glucose tolerance among two parents of young-onset NIDDM patients suggest heterogeneity of the mode of inheritance of NIDDM among families. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Tolerance Test; HLA-DR Antigens; Humans; Insulin; Male; Middle Aged; Parents; Reference Values | 1992 |
Immunogenetic and nutritional profile in insulin-using youth-onset diabetics in Korea.
There are few reports on the genetic, immunological and nutritional characteristics of insulin-using youth-onset diabetes mellitus, insulin-dependent diabetes mellitus (IDDM) and malnutrition-related diabetes mellitus (MRDM) in Korea. Among 1266 hospitalized Korean diabetics, 29 (2.3%) were IDDM and 84 (6.6%) were MRDM. A diabetes history of first-relatives (28.6%) was more frequently found in the MRDM group than in the IDDM (14.8) and non-insulin-dependent diabetes mellitus (NIDDM) (19.0%) groups. HLA-DR4 was more common among IDDM (54.2%) and MRDM (52.4%) patients than controls (26.3%), and HLA-DR3 was more common among only IDDM patients (29.2%) than controls (10.9%). Conventional islet-cell antibodies were detected in 8 of 15 IDDM patients tested (53.3%) and in 11 of 22 MRDM patients (50.0%). MRDM patients had higher serum basal (1.02 +/- 0.51 ng/ml) and peak (1.44 +/- 0.76 ng/ml) C-peptide concentrations than IDDM patients, but lower concentrations than NIDDM patients. Before the onset of diabetes, the calorie intake of 21 MRDM patients assessed was 63.1% of the daily requirement and the intake of carbohydrate, protein and fat was 71.7%, 55.9% and 39.8%, respectively. In summary, our data suggest that IDDM in Korea is associated with HLA-DR3 or HLA-DR4, indicating a risk for IDDM in Western societies; furthermore, MRDM has a history of undernutrition at the preonset period and is also associated with HLA-DR4. It might be also concluded that MRDM in Korea is another expression of IDDM caused by the shortage of some nutrients for the structural and/or functional maintenance of pancreatic beta-cells. Topics: Adolescent; Autoantibodies; Blood Glucose; Blood Proteins; C-Peptide; Cholesterol, HDL; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diet; Female; Glucose Tolerance Test; Glycated Hemoglobin; HLA-DR Antigens; Humans; Islets of Langerhans; Korea; Male; Nutrition Disorders; Triglycerides; Vitamins | 1992 |
In search of predictive markers of remission from insulin dependence in type 1 diabetes: a preliminary report.
We studied 18 newly diagnosed diabetic patients (8 males and 10 females, aged 18-26 years, within 10-120 days from the onset of symptoms) who were submitted for 15 days to intensive insulin therapy performed via subcutaneous insulin infusion (CSII). We investigated some metabolic and immunological parameters in order to identify a possible marker to predict the selection of patients potentially more responsive to CSII treatment for the remission of type 1 diabetes. In accordance with the International Diabetes Immunology Group we considered clinical remission as being the withdrawal of insulin therapy for at least 3 months. In order to assess beta-cell function a fasting and post-prandial serum C-peptide, blood glucose and HbA1c were performed on all patients before, and 3 days after, the discontinuation of CSII. Islet cell antibodies were determined in all sera by indirect immunofluorescence. Analysis of T-lymphocyte subpopulations was carried out before starting the therapy. The following monoclonal antibodies were used: CD4, CD8, CD57, CD25, HLA-DR. The levels of C3 and C4 and serum IgG, IgA and IgM were also evaluated. After CSII, 11 of 18 patients showed remission. At the beginning of the study we observed no major difference in metabolic parameters between the two groups. Interestingly, the patients who exhibited remission presented a statistically higher percentage of positive cells for CD57, HLA-DR and CD25 surface antigens, significantly lower C4 levels and CD4/CD8 ratio and significantly higher IgG levels compared with patients who did not show any remission.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Antigens, CD; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Glycated Hemoglobin; Humans; Immunoglobulins; Insulin; Insulin Infusion Systems; Male; T-Lymphocyte Subsets; Time Factors | 1992 |
Islet-cell antibodies and endogenous insulin secretion in Sudanese diabetic children.
Cytoplasmic islet-cell antibodies (ICA) and endogenous insulin secretion were studied in 46 Sudanese children (mean age 11.6 years) with newly diagnosed insulin-dependent diabetes mellitus (IDDM). Islet-cell antibodies were detected both by the indirect immunofluorescence (IF) and complement fixation (CF) methods. Endogenous insulin levels were measured as C-peptide concentration using radio-immunoassays. The degree of metabolic control of diabetics was judged by the presence of diabetic ketoacidosis (DKA) at onset, glycated haemoglobin (HbA1c) level and insulin requirement, expressed as dose per kg body weight per day, at the time of presentation. Twenty-nine patients (63%) had either IF-ICA or CF-ICA or both in their sera. These figures are significantly higher than those reported for African populations. Islet-cell antibody positive patients had significantly lower C-peptide concentration, higher HbA1c level, higher insulin requirement and higher prevalence of ketoacidosis at presentation. Furthermore, the C-peptide levels were higher in CF-ICA positive patients than in subjects who showed only IF-ICA positivity. Our findings show a clear association between ICA and severity of diabetes at clinical onset and also suggest that the presence of CF-ICA at or shortly after diagnosis of IDDM is indicative of preservation of some functioning beta-cell mass. Topics: Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Fluorescent Antibody Technique; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Sudan | 1992 |
Metabolic results at 6 and 12 months after pancreas transplantation.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Pancreas Transplantation; Time Factors | 1992 |
Long-term glucose homeostasis and insulin secretion following segmental heterotopic pancreas transplantation.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glucose Tolerance Test; Glycated Hemoglobin; Homeostasis; Humans; Insulin; Insulin Secretion; Kidney Transplantation; Pancreas Transplantation; Uremia | 1992 |
Human islet allotransplantation in 18 diabetic patients.
Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Islets of Langerhans Transplantation; Liver Cirrhosis; Liver Transplantation; Middle Aged | 1992 |
Regional cytokine changes following OKT3 induction for islet cell transplantation in humans: early increase in portal and systemic levels of interleukin-6 and tumor necrosis factors.
Topics: C-Peptide; Cytokines; Diabetes Mellitus, Type 1; Humans; Interleukin-6; Islets of Langerhans Transplantation; Muromonab-CD3; Time Factors; Tumor Necrosis Factor-alpha | 1992 |
Allotransplantation of fresh islets in four type I diabetic patients.
Topics: Adult; C-Peptide; Cell Separation; Centrifugation, Density Gradient; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Transplantation, Homologous | 1992 |
Human islet cotransplantation with liver or kidney.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glycated Hemoglobin; Graft Rejection; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Liver Diseases; Liver Transplantation; Tissue Donors | 1992 |
Evidence of xenograft function in a diabetic patient grafted with porcine fetal pancreas.
Topics: Adult; Animals; Antibodies, Heterophile; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Fetal Tissue Transplantation; Glycated Hemoglobin; Humans; Immunoglobulin M; Immunosuppressive Agents; Kidney Transplantation; Lymphocytes; Pancreas Transplantation; Swine; Transplantation, Heterologous | 1992 |
Sequential metabolic studies of pancreas allograft function in type 1 diabetic recipients.
We have previously shown that the loss of acute first phase insulin secretion precedes pancreas allograft rejection and development of glucose intolerance in Type 1 diabetic patients. In order to examine whether there is a progressive loss of phases of insulin secretion and beta-cell function in technically successful pancreas transplants during the first year, we measured glucose, insulin, and C-peptide responses to physiological (mixed meal) and pharmacological (IV glucose and IV glucagon) stimulation in 27 glucose-tolerant, insulin-independent allograft recipients at 3, 6, and 12 months. Mean +/- SE fasting serum glucose levels were normalized throughout the study period. Postprandial serum glucose profiles tended to increase by 12 months compared to 3 and 6 months, although peak glucose levels were not statistically different. Following pancreas transplantation, basal serum insulin levels were high at 3 months (163 +/- 17 pM), 6 months (165 +/- 22 pM), and 12 months (248 +/- 54 pM, p = NS) in the Type 1 diabetic pancreas allograft recipients when compared to normal (25 +/- 3 pM). We observed slight elevations in postprandial insulin and C-peptide profiles at 12 months compared to 3 and 6 months. Following IV glucose and glucagon stimulation, serum insulin and C-peptide levels as well as phases of insulin release did not differ over the 12-month study period. Similarly, the glucose decay constant (KG) was nearly identical at 3, 6, and 12 months. In summary, 1 year following successful whole cadaveric, heterotopic pancreas transplantation in Type 1 diabetic recipients, fasting serum glucose remains normalized, while postprandial glucose tends to rise.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Analysis of Variance; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Eating; Female; Follow-Up Studies; Glucagon; Glucose Tolerance Test; Humans; Insulin; Kidney Transplantation; Male; Pancreas Transplantation; Regression Analysis; Transplantation, Homologous | 1992 |
Demonstration of islet cell antibodies in apparently non-insulin dependent diabetic patients; a marker for the later development of insulin dependency.
One hundred and ten diabetic patients who were apparently non-insulin dependent at 1984 were followed up for 5 years from 1984 to 1989. Islet cell antibodies (ICA) of the patients were tested in 1987. Eleven patients were positive for ICA and 99 were negative. There was no significant difference in age, sex, duration of diabetes, and HbA1c levels between ICA-positive and negative groups. Six of 11 (54.5%) patients in ICA-positive group developed insulin-requiring state in the period from 1984 to 1989, while only 5 of 99 (5.1%) patients in ICA negative group became insulin-requiring. Glucagon tolerance test (1 mg i.v.) was performed on 8 patients who developed insulin-requiring state; among them 4 patients were ICA-positive and other 4 patients were ICA negative. The serum C-peptide response to intravenous glucagon injection was markedly decreased in 3 of the 4 ICA-positive patients, and only mildly decreased in all the 4 ICA-negative patients. The markedly decreased C-peptide response indicates that these ICA-positive subjects had developed insulin-dependency. We conclude that the presence of ICA in apparently non-insulin dependent diabetics indicates a high risk for developing insulin-dependency. Topics: Autoantibodies; Biomarkers; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Disease Progression; Female; Glucagon; Humans; Islets of Langerhans; Male; Middle Aged; Prognosis | 1991 |
Two patients with insulin resistance due to decreased levels of insulin-receptor mRNA.
Mutations have been identified in the insulin-receptor gene in insulin-resistant patients. We studied two patients with acanthosis nigricans and insulin resistance caused by a decrease in the number of cell surface insulin receptors. Patient 1 was an 11-yr-old boy with a fasting insulin level of 2130 pM; patient 2 was a 14-yr-old girl with hyperandrogenism and a fasting insulin level of 580-740 pM. Based on Southern-blotting studies, the structure of both alleles of the insulin-receptor gene in both patients appeared to be grossly normal. There was no evidence of insertions, deletions, or major rearrangements. Moreover, the nucleotide sequences of all 22 exons of the gene were normal in both patients. Thus, the predicted amino acid sequences of both patients' insulin receptors were normal. In Epstein-Barr virus-transformed lymphoblasts from patient 1, insulin-receptor mRNA levels were so low they could not be detected with an RNase A protection assay, whereas mRNA levels from patient 2 were in the lower half of the normal range. By use of a more sensitive assay based on the polymerase chain reaction, insulin-receptor mRNA could be detected in Epstein-Barr virus-transformed lymphoblasts from both patients. Moreover, because of the existence of silent polymorphisms in the nucleotide sequences, it was possible to differentiate the two alleles of the insulin-receptor gene in both patients. In patient 2, the two alleles were expressed asymmetrically, with 90% of the mRNA molecules having been transcribed from one allele but only 10% transcribed from the second allele. This suggests that there is an unidentified mutation in the underexpressed allele that acts in a cis-dominant fashion to decrease insulin-receptor mRNA levels. However, in patient 1, both alleles were expressed symmetrically in similarly low levels. Although not proven, it seems likely that the mutations that decrease insulin-receptor mRNA levels in patient 1 also map to the insulin-receptor locus. Topics: Adolescent; Blood Glucose; Blotting, Southern; C-Peptide; Cell Line; Cell Transformation, Viral; Child; Diabetes Mellitus, Type 1; DNA; DNA Probes; DNA Restriction Enzymes; Female; Herpesvirus 4, Human; Humans; Insulin; Insulin Resistance; Lymphocytes; Male; Polymorphism, Restriction Fragment Length; Receptor, Insulin; Reference Values; RNA, Messenger; Testosterone | 1991 |
Insulin clearance and diabetes.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Odds Ratio | 1991 |
Increased somatostatin response to glucagon in insulin-dependent diabetes mellitus.
The dynamic study of somatostatin secretion was performed in patients with insulin-dependent diabetes mellitus and age- and sex matched volunteers. The basal levels of immunoreactive somatostatin, as well as its response to i.v. Glucagon (1 mg) at 10 and 20 min with consequent hyperglycemia were increased in most of diabetic patients as compared with the healthy controls. Our results suggest that the glucagon test could be used for estimating the somatostatin secretion in diabetes mellitus. This would reveal some impaired interactions between the endocrine function of the pancreas in diabetes mellitus. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Cross Reactions; Diabetes Mellitus, Type 1; Female; Gastrins; Glucagon; Humans; Insulin; Radioimmunoassay; Somatostatin | 1991 |
[Type 1 or Type 2 diabetes: diagnostic aids in clinically uncertain cases].
Topics: Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Insulin Antibodies; Islets of Langerhans; Ketone Bodies | 1991 |
Neonatal macrosomia and hypoglycaemia in children of mothers with insulin-treated gestational diabetes mellitus.
All newborn children to mothers with gestational diabetes mellitus (GDM) in the county of Orebro were investigated during a one year prospective study. Neonatal macrosomia (birthweight greater than 3 SD) was observed in 27% of children of mothers with GDM and was significantly correlated to the cord C-peptide concentration. Hypoglycaemia (B-glucose less than 1.5 mmol/l) was observed in 38% of the children, most frequently two hours after delivery. Hypoglycaemia was not more common in macrosomic children and could not be predicted by the blood glucose concentration of the mother at delivery or by the cord C-peptide level. It is concluded that mothers with GDM must be intensively treated in order to avoid the occurrence of macrosomia in their infants and that the newborn child must be carefully observed and treated in order to avoid neonatal hypoglycaemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes, Gestational; Female; Fetal Macrosomia; Glycated Hemoglobin; Humans; Hypoglycemia; Infant, Newborn; Insulin; Pregnancy; Pregnancy in Diabetics | 1991 |
Serum ketone response to glucagon as a marker of insulin dependency in diabetics.
The serum ketone response to glucagon was measured in 10 patients with IDDM and 37 with NIDDM. In both groups, serum 3-hydroxybutyrate increased significantly after intravenous injection of 1 mg glucagon. The difference between the serum level of 3-hydroxybutyrate at 30 min and basal level [delta 3-OHBA(30')] was 133 +/- 25 mumol/l in the patients with IDDM, 13 +/- 8 mumol/l in those with NIDDM treated by diet alone or with oral hypoglycemic agents and 23 +/- 13 mumol/l in those with NIDDM treated with insulin. The delta 3-OHBA(30') was significantly greater in IDDM patients than in both groups of NIDDM patients (P less than 0.001). The delta 3-OHBA(30') was greater than 87 mumol/l in eighty percent of IDDM patients, but smaller than 87 mumol/l in both groups of NIDDM patients. The delta 3-OHBA(30') was correlated with the difference between the plasma level of C-peptide at 6 min and basal level [delta CPR(6')] (r = -0.540, P less than 0.001). The delta 3-OHBA(30') was not correlated with fasting plasma levels of glucose, fructosamine or hemoglobin A1c. These observations show that measurement of the serum ketone response to glucagon is a useful marker of insulin dependency. In order to determine insulin dependency, the simultaneous measurement of concentrations of ketones and C-peptide is indicated during the glucagon stimulation test. Topics: 3-Hydroxybutyric Acid; Acetoacetates; Adult; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids, Nonesterified; Female; Fructosamine; Glucagon; Hexosamines; Humans; Hydroxybutyrates; Ketone Bodies; Kinetics; Male; Middle Aged; Regression Analysis | 1991 |
Pancreatic beta cell function in children and adolescents after bone marrow transplantation.
Topics: Adolescent; Bone Marrow Transplantation; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1991 |
Fresh human islet transplantation to replace pancreatic endocrine function in type 1 diabetic patients. Report of six cases.
The aim of this study was to evaluate the feasibility of islet allografts in patients with type 1 diabetes mellitus. Six patients received human islets from either one or two donors via the portal vein, after (n = 4) or simultaneously with (n = 2) a kidney graft. The patients with functioning kidney grafts (nos. 1-4) were already on triple immunosuppressive therapy (cyclosporine A, azathioprine, prednisone). Prednisone was increased to 60 mg/day for 15 days after the islet transplant in patient 1. Patients 2-4 and the patients who underwent a simultaneous kidney-islets graft (nos. 5, 6) also received antilymphocyte globulin. Intravenous insulin was given for the first 15 days to maintain blood glucose concentrations within the normal range. Patient 1 rejected the islets within 15 days of islet transplantation. In patient 2, a 25% reduction in insulin requirement was observed and 12 months after transplantation post-prandial serum C-peptide was 1.5 ng/ml. In patient 3, the insulin requirement decreased from 40 to 8 units/day with a post-prandial serum C-peptide of 4.1 ng/ml 12 months after islet transplantation. In patient 4 the post-prandial secretion of C-peptide increased to 6.4 ng/ml. Six months after the islet infusion, insulin therapy was discontinued and HbA1c, 24-h metabolic profile and oral glucose tolerance test remained within the normal range. He had remained off insulin for 5 months until recently, when foot gangrene paralleled a worsening of post-prandial glycaemic control. Twelve months after transplantation he is receiving 8 units insulin/day.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Antilymphocyte Serum; Azathioprine; Blood Glucose; C-Peptide; Cell Separation; Cells, Cultured; Cyclosporine; Diabetes Mellitus, Type 1; Histocompatibility Testing; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation; Monitoring, Physiologic; Prednisone; Tissue and Organ Procurement | 1991 |
C-peptide/creatinine ratio in early morning urine as an indicator of residual B-cell function in insulin-dependent diabetes.
The C-peptide/creatinine (Cr) ratio in early morning urine was evaluated to assess B-cell function. The subjects were 12 boys and 36 girls with insulin-dependent diabetes mellitus (IDDM). The controls were 130 boys and 137 girls aged 4-15 years. There was a significant inverse correlation of this ratio with the duration of insulin therapy (r = -0.5807, P less than 0.01). The daily insulin dose in U/kg was significantly different among the following groups: 1.22 +/- 0.31 U/kg in group 1 with undetectable C-peptide, 0.94 +/- 0.37 in group 2 with a decreased ratio and 0.45 +/- 0.28 in group 3 with a normal ratio. HbA1 levels were 11.3 +/- 1.6% in group 1 and 9.2 +/- 1.1% in group 3. The difference was significant. The result shows that the C-peptide/Cr ratio in early morning urine is useful for assessing B-cell function in diabetic children. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Circadian Rhythm; Creatinine; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Reference Values; Sex Factors; Time Factors | 1991 |
Increasing incidence of hypoglycemic coma in children with IDDM.
To examine the incidence of hypoglycemic coma in children with insulin-dependent diabetes mellitus (IDDM) over 8 yr from 1981 to 1988 and to investigate the importance of residual beta-cell function of HbA1 levels and other variables as risk factors for hypoglycemic coma.. The study consisted of 155 children with IDDM aged less than 16 yr at study entry. Mean age at onset of diabetes was 7.9 yr (range 1.1-15.6 yr). We made a prospective assessment of hypoglycemic coma episodes, with a standardized questionnaire, over a total observation time of 816.6 person-yr. Three monthly clinical and laboratory examinations, which included determinations of C-peptide and HbA1 levels, were conducted. We compared children with hypoglycemic coma (cases) with children without hypoglycemic coma (controls) in a case-control analysis matched for diabetes duration. Yearly incidence of hypoglycemic coma, calculated as the number of subjects having an attack in 1 yr divided by the cumulative number of person-years for that year, was measured. Univariate and multivariate odds ratios were calculated from logistic regression.. Over the first 4 yr, the average yearly incidence was 4.4/100 person-yr compared with 7.4/100 person-yr during the later 4 yr (P less than 0.0001). This tendency was accompanied by intensification of insulin treatment with an increase in the mean number of daily injections and a decrease in mean HbA1 levels. In the case-control analysis, absent residual beta-cell function was the most important risk factor for hypoglycemic coma (adjusted odds ratio 7.8, 95% confidence intervals 2.0-31.2), followed by near-normal HbA1 levels (adjusted odds ratio 4.5, 95% confidence intervals 1.9-10.5).. In this group of children, improvement of glycemic control apparently led to an increase in the incidence of severe hypoglycemia. In children with recurrent hypoglycemic coma and undetectable C-peptide levels, it may be safer to aim for somewhat less tight glycemic control. Topics: Adolescent; Animals; Biomarkers; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Incidence; Insulin; Insulin Antibodies; Insulin Coma; Male; Odds Ratio; Recombinant Proteins; Regression Analysis; Risk Factors; Swine; Switzerland | 1991 |
Hypoglycemia after successful pancreas transplantation in type I diabetic patients.
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Eating; Glucose Tolerance Test; Humans; Hypoglycemia; Insulin; Insulin Secretion; Kidney Transplantation; Pancreas Transplantation; Transplantation, Heterotopic; Transplantation, Homologous | 1991 |
Patterns of insulin dependence in an African diabetic clinic.
Analysis of the age of onset of diabetes amongst insulin-treated patients in a large African diabetic clinic revealed a bimodal type of distribution, 23 per cent having an age of onset before 30 years and 77 per cent with onset at greater than or equal to 30 years of age. All 66 of the young insulin-treated group (21.7 +/- 4.8 years (mean +/- 1 SD)), and a random selection of 50 older insulin-treated patients (49.7 +/- 10 years), were studied. The older group were better controlled (HbA1 8.4 +/- 1.7 per cent vs. 10.8 +/- 2.6 per cent, p less than 0.001), on lower doses of insulin (49 +/- 23 vs. 71 +/- 23 u/day, p less than 0.001) and had higher body mass index (26.0 +/- 5.6 vs. 21.8 +/- 3.5, p less than 0.001). Serum C-peptide (0.24 +/- 0.15 vs. 0.07 +/- 0.10 nmol/l, p less than 0.0001), and C-peptide/glucose ratio (2.57 +/- 2.65 vs. 0.56 +/- 0.98 nmol/mmol x 10(2), p less than 0.001) were very significantly higher in older patients. Patients with later onset disease thus had better preservation of pancreatic function, higher body mass index and better glycaemic control on lower doses of insulin. These features suggest that older insulin-treated patients could in fact be 'Type 2' or non-insulin dependent patients, and the condition may be controllable with diet and/or oral hypoglycaemic agents, at least in some. Topics: Adult; Age Factors; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Middle Aged; South Africa | 1991 |
Circadian variation of basal and postprandial insulin sensitivity in healthy individuals and patients with type-1 diabetes.
The circadian variation of basal and postprandial plasma glucose and insulin levels was analyzed in 10 healthy individuals and 10 type-1 diabetic patients treated with a glucose-controlled insulin infusion system. In both groups the postprandial glycemic response to identical low caloric mixed meals ingested at 8.00 am, 1.00 pm, and 6.00 pm increased significantly in the course of the day. In contrast to findings in conventional insulin therapy mean postprandial insulin requirements of the diabetic patients increased from 8.5 +/- 3.0 IU for breakfast to 9.1 +/- 2.0 for lunch and 10.9 +/- 3.0 for dinner (p less than 0.01). Repeated studies with different test meals showed that in the diabetic patients the circadian deterioration of carbohydrate tolerance was reduced after a fibre rich meal with low glycemic effect and insulin requirements. In the healthy subjects basal insulin levels at 8.00 am were 35% higher than at 1 and 6.00 pm (p less than 0.01). Basal insulin requirements of the diabetic patients increased significantly from a night value of 0.7 IU/h to 1.18 IU/h during the early morning and remained constant throughout day time. We conclude that circadian changes in postprandial carbohydrate tolerance are independent from the endogenous rhythmics of basal glucose metabolism. In diabetic patients the circadian pattern of postprandial responses is substantially determined by exogenous factors like diet composition caloric intake and therapeutic regimen. Topics: Adult; Blood Glucose; Body Mass Index; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Eating; Energy Intake; Female; Humans; Insulin; Male; Reference Values | 1991 |
[Insulin/glucagon relationship in spontaneous diabetic remission].
We define diabetic remission as the disappearance of clinical symptoms with normalization of blood glucose for a period over 15 days after withdrawal of insulin therapy. We studied 21 insulin-dependent diabetic children in remission (10 boys and 11 girls) and 29 normal children matched in age and sex as controls. Two tests were performed, intravenous glucose (IVGT) and glucose post-tolbutamide (PTGT). Two remission groups were studied with IVGT. Glucose, insulin, somatotropin and glucagon were determined in one and glucose and C-peptide in the other. Insulin secretion after IVGT was very low in the remission group, not surpassing basal value when stimulated. Only two girls showed normal or high insulin values during the study, and one of them showed the common hypoinsulinism of the remission group in a second study. The kinetics of glucagon and somatotropin secretion in the remission group were normal with low values of glucagon. When the integrated area (0-120 min) of hormone secretion (insulin, somatotropin and glucagon) was determined, the remission group had lower insulin and glucagon values (p less than 0.05) and identical growth hormone as the normal group. The insulin/glucagon ratio in normals and in remission were similar. During IVGT the remission group studied for C-peptide showed lower C-peptide values than normal group, resembling insulin behavior. In both groups, the glucose disappearance rate ("K" value) was higher in normals than in remissions (p less than 0.001). During the PTGT the normal group showed a peak of insulin secretion after tolbutamide and glucose stimulation. In the remission group, glucose was higher and insulin secretion lower than in the normal group, without a peak of insulin, and growth hormone and glucagon secretion were also lower.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Male; Remission Induction | 1991 |
Lipoprotein (a) and microvascular disease in type 1 (insulin-dependent) diabetes.
The influence of albuminuria and proliferative retinopathy on concentration of serum lipoprotein (a) was examined cross-sectionally in 90 Type 1 diabetic patients. Concentrations of lipoprotein (a) were less in those with normoalbuminuria (90 (8-882) (median (range] U l-1) than in those with micro- or macro-albuminuria (137 (19-1722) U l-1, p less than 0.05). The prevalence of patients whose lipoprotein (a) concentrations were greater than 200 U l-1 was also greater (45% vs 24%, p = 0.03) among patients with albuminuria, but no difference was found between the microalbuminuric and macroalbuminuric groups (53 and 41%, respectively), or between those with or without proliferative retinopathy. The present finding that lipoprotein (a) concentrations may be increased at an early stage of diabetic renal disease may in part account for the excess ischaemic heart disease associated with diabetic nephropathy. Topics: Albuminuria; Apolipoproteins B; Biomarkers; Blood Glucose; Blood Pressure; C-Peptide; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Coronary Disease; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Lipoprotein(a); Lipoproteins; Male; Middle Aged; Triglycerides; Vascular Diseases | 1991 |
Urinary excretion of chromium, copper, and manganese in diabetes mellitus and associated disorders.
The urinary excretion of chromium, copper and manganese was determined in 185 diabetics and in an equal number of control subjects by measuring the concentration of each of these metals using electrothermal atomic spectrophotometry and dividing the values by the urinary concentration of creatinine (creat) in each subject. The mean (SEM) values for the overall diabetics and the control group were 2.32 (0.17) and 2.62 (0.22) mumol Cr/mole of creat, 76.5 (5.5) and 73.9 (6.1) mumol Cu/mole of creat, and 3.56 (0.44) and 2.66 (0.3) mumol Mn/mole of creat, respectively. There was no correlation between the urinary excretion of any of the metals examined and age or sex of either group. While the cardiovascular or ophthalmologic diseases associated with diabetes did not influence the excretion of any of these metals, significantly higher urinary excretion of Cu was exhibited by diabetics with neuropathy (p < 0.0027) or infections (p < 0.014) than by those without. Also, diabetics with liver disorders or those who were not treated with insulin excreted significantly more Mn than did their diabetic counterparts. Topics: C-Peptide; Chromium; Copper; Creatinine; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Liver Diseases; Male; Manganese; Middle Aged; Reference Values; Spectrophotometry, Atomic; Trace Elements | 1991 |
[Clinical significance of measuring serum c-peptide before and after glucagon injection].
To evaluate pancreatic beta-cell secretory activity, c-peptide concentrations before and 6 minutes after an i.v. injection of glucagon were measured in 12 normal subjects (group N), 23 diabetics treated with diet control and oral antidiabetics (group DI) and 71 patients treated with insulin (group DII). The results showed that the fasting c-peptide concentration in group N and group DI were comparable, but significantly higher than that in group DII. An overlap was found between fasting c-peptide from 6 diabetics in group DI and that from group DII. There were significant differences among the c-peptide concentrations 6 minutes after glucagon injection in the three groups and there was no overlap between c-peptide in group DI and that in group DII 6 minutes after injection. The above-mentioned data suggest that c-peptide concentration 6 minutes after glucagon injection may reflect beta-cell secretory activity better than fasting c-peptide. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Humans; Male; Middle Aged | 1991 |
Poor predicting values in obtaining non-insulin requiring remission using proinsulin/C-peptide ratios.
Topics: Biomarkers; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Humans; Prognosis; Proinsulin | 1991 |
Renal and splanchnic exchange of human biosynthetic C-peptide in type 1 (insulin-dependent) diabetes mellitus.
Biosynthetic human C-peptide or NaCl (154 mmol.l-1) was given intravenously to 13 Type 1 (insulin-dependent) diabetic patients to determine the renal and splanchnic exchange of C-peptide. Catheters were inserted percutaneously into an artery and a renal and hepatic vein. Infusions of C-peptide were given for 60 min at two dose levels (5 and 30 pmol.kg-1.min-1). Insulin was infused throughout the study (0.5 mU.kg-1.min-1) and plasma glucose was kept constant by a variable glucose infusion. The regional blood flows were measured by indicator dilution techniques. In 11 of the 13 patients basal C-peptide levels were not detectable. The arterial steady-state C-peptide concentration was 0.81 +/- 0.10 nmol.l-1 and 2.33 +/- 0.30 nmol.l-1 at the low and high rate infusions, respectively. Renal uptake was 124 +/- 18 pmol.min-1 at the low infusion corresponding to 39% of the infused amount. At the higher dose C-peptide infusion renal uptake increased to 155 +/- 21 pmol.min-1 (p less than 0.05). Urinary excretion of C-peptide was 7 +/- 2 pmol.min-1 at the low dose infusion and increased to 34 +/- 6 pmol.min-1 at the high dose infusion (p less than 0.01). The proportions of infused amount excreted were fairly constant and between 2% and 3%. No net exchange of C-peptide was found across the splanchnic vascular bed. The rate of glucose infusion had to be increased by 35% during the low dose C-peptide, but not during NaCl infusion in order to maintain a constant plasma glucose concentration.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Catecholamines; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Fatty Acids, Nonesterified; Female; Glucagon; Glucose; Humans; Infusions, Intravenous; Insulin; Kidney; Male; Norepinephrine; Sodium Chloride; Spleen | 1991 |
Metabolic control, residual insulin secretion and self-care behaviours in a defined group of patients with type 1 diabetes.
A population of 185 type 1 diabetes patients (insulin-dependent, IDDM), 25-45 years old, was studied retro- and prospectively over a 9-year period with the aim of analysing background factors of importance for the ability to perform adequate self-care. Expressed as mean HbA1c, the metabolic control was slightly improved at the end of the study, when the insulin schedule had been changed in 60% of the patients to multidose treatment. The degree of metabolic control remained constant over the years. The impact of residual insulin secretion, measured as 24-hour urinary C peptide, was low. Patients with less good metabolic control often had a poor educational background and made less use of self-monitoring of blood glucose (SMBG); they also experienced difficulties with SMBG. The applied knowledge of diabetes also differed between groups with good and poor control. Subjectively, most patients considered their metabolic control to be good, irrespective of the HbA1c values. When asked about their own diabetes complications, their answers were often discrepant from the medical records. Patients with particularly "good" or "poor" metabolic control were on the whole less satisfied with the education and information received than those with intermediate blood glucose regulation. Development of strategies for individually adjusted education seems important. Topics: Adult; Attitude to Health; Blood Glucose Self-Monitoring; C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Male; Middle Aged; Patient Education as Topic; Prospective Studies; Retrospective Studies; Self Care | 1991 |
Heterogeneity of non-insulin-dependent diabetes mellitus in HLA types and clinical features: comparison with insulin-dependent diabetes mellitus.
We determined HLA types in 110 Japanese patients with non-insulin-dependent diabetes mellitus (NIDDM) and studied the relationship between the HLA phenotypes and clinical features. Sixty-nine patients with insulin-dependent diabetes mellitus (IDDM) and 100 healthy blood donors served as controls. Concerning HLA DR and DQ loci, frequencies of DR4, DRw9 and DQw3.2 were higher, and those of DR2, DRw8, DRw11, DRw12 and DQw1 were lower in patients with IDDM compared than in healthy controls. There were no differences between NIDDM and normal controls in the frequency of a particular HLA DR antigen except for a decreased frequency in DRw11 in the former. The frequency of DQw3.2 antigen in NIDDM was intermediate between IDDM and normal controls. There were some differences between DQw3.2-positive and -negative NIDDM patients in clinical features. Those who showed low C-peptide responses during oral glucose tolerance test were more frequently found among DQw3.2-positive NIDDM patients. These results suggest that Type 1 diabetes mellitus may have a mild clinical course and is found among the Japanese NIDDM population. Topics: Age Factors; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gene Frequency; Glucose Tolerance Test; HLA Antigens; HLA-DQ Antigens; HLA-DR Antigens; Humans; Immunophenotyping; Insulin; Male | 1991 |
Characterization of the insulin-antagonistic effect of growth hormone in man.
The insulin-antagonistic effect of growth hormone was characterized by infusing the hormone at three different infusion rates (6, 12 or 24 mU.kg-1.min-1) for one h in 11 healthy subjects. The insulin effect was measured with the euglycaemic clamp technique combined with D-(3-3H)-glucose infusion to evaluate glucose production and utilization. A control study with NaCl (154 mmol.l-1) infusion was also performed. The insulin levels during the clamps were similar in all studies (36 +/- 0.2 mU.l-1). Peak growth hormone levels were reached at 60 min (growth hormone 6 mU.kg-1.h-1: 31 +/- 5; growth hormone 12 mU.kg-1.h-1: 52 +/- 4 and growth hormone 24 mU.kg-1.h-1; 102 +/- 8 mU.l-1). The insulin-antagonistic effect of growth hormone started after approximately 2 h, was maximal after 4-5 h (approximately 39% inhibition of glucose infusion rate between control and growth hormone 24 mU.kg-1.h-1) and lasted for 6-7 h after peak levels. The resistance was due to a less pronounced insulin effect both to inhibit glucose production and to stimulate glucose utilization. Growth hormone infusion of 12 mU.kg-1.h-1 induced a similar insulin-antagonistic effect as the higher infusion rate whereas 6 mU.kg-1.h-1 induced a smaller response with a duration of 1 h between 3-4 h after peak levels of growth hormone. The present study demonstrates that growth hormone levels similar to those frequently seen in Type 1 (insulin-dependent) diabetic patients during poor metabolic control or hypoglycaemia, have pronounced insulin-antagonistic effects.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Fatty Acids, Nonesterified; Female; Glucose Clamp Technique; Growth Hormone; Humans; Infusions, Intravenous; Insulin; Insulin Antagonists; Kinetics; Male; Reference Values | 1991 |
Decreased hepatic glucagon responses in type 1 (insulin-dependent) diabetes mellitus.
The effect of glucagon infusion on hepatic glucose production during euglycaemia was evaluated in seven Type 1 (insulin-dependent) diabetic patients and in ten control subjects. In the diabetic subjects normoglycaemia was maintained during the night preceding the study by a variable intravenous insulin and glucose infusion. During the study endogenous insulin secretion was suppressed by somatostatin (450 micrograms/h) and replaced by insulin infusion (0.15 mU.kg-1.min-1). 3H-glucose was infused for isotopic determination of glucose turnover. Plasma glucose was clamped at 5 mmol/l for 2 h 30 min and glucagon (1.5 ng.kg-1.min-1) was then infused for the following 3 h. Hepatic glucose production and glucose utilisation were measured during the first, second and third hour of the glucagon infusion. Basal hepatic glucose production (just prior to glucagon infusion) was similar in diabetic (1.2 +/- 0.3 mg.kg-1.min-1) and control (1.6 +/- 0.1 mg.kg-1.min-1) subjects. In diabetic patients hepatic glucose production rose slowly to 2.1 +/- 0.5 mg.kg-1.min-1 during the first hours of glucagon infusion and stabilized at this level (2.4 +/- 0.5 mg.kg-1.min-1) in the third hour. In control subjects hepatic glucose production increased sharply to higher levels than in the diabetic subjects (3.4 +/- 0.3 mg.kg-1.min-1) during the first and second hour of glucagon infusion (p less than 0.05) and then gradually fell (2.9 +/- 0.4 mg.kg-1.min-1) during the third hour. In conclusion, when stimulated with glucagon at a physiologic plasma concentration diabetic patients had 1) an overall reduced hepatic glucose production response and 2) an abnormal sluggish response pattern.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: 3-Hydroxybutyric Acid; Adult; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glucose; Glycerol; Growth Hormone; Humans; Hydroxybutyrates; Infusions, Intravenous; Insulin; Insulin Secretion; Kinetics; Lactates; Liver; Male; Reference Values; Time Factors | 1991 |
Effects of pancreas transplantation on postprandial glucose metabolism.
Because a pancreas allograft is placed in the pelvis, pancreas transplantation abolishes the normal gradient between portal-vein and peripheral-vein insulin concentrations and causes systemic hyperinsulinemia. Whether pancreas transplantation restores carbohydrate metabolism to normal is not known.. We studied seven patients with insulin-dependent diabetes mellitus after pancreas-kidney transplantation, seven nondiabetic patients after kidney transplantation (to control for immunosuppression), and eight normal subjects. Measurements were made after an overnight fast and after ingestion of a mixed meal.. Although plasma glucose concentrations did not differ in the two transplant groups, plasma insulin concentrations were significantly higher in the diabetic pancreas-kidney recipients than in the nondiabetic kidney recipients, both before the meal (mean +/- SE, 102 +/- 15 vs. 53 +/- 6 pmol per liter; P less than 0.05) and afterward (123 +/- 22 vs. 61 +/- 6 nmol per liter per six hours; P less than 0.05). Plasma C-peptide concentrations were the same in both groups, indicating that hyperinsulinemia was due to decreased insulin clearance rather than increased insulin secretion. Despite drainage of the venous effluent from the transplanted pancreas into the systemic circulation, the values for splanchnic clearance of ingested glucose, suppression of hepatic glucose release, incorporation of carbon dioxide into glucose, stimulation of glucose oxidation, glucose uptake, and forearm glucose clearance were all similar in the transplant groups and differed minimally from the values in the normal group. The similar rates of glucose uptake in the presence of higher systemic insulin concentrations indicated that the extrahepatic tissues of the diabetic pancreas-kidney recipients were insulin-resistant.. Despite systemic delivery of insulin, pancreas-kidney transplantation in patients with diabetes results in carbohydrate metabolism similar to that in nondiabetic subjects receiving the same immunosuppressive agents after kidney transplantation. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Female; Glucose; Humans; Insulin; Kidney Transplantation; Male; Metabolic Clearance Rate; Pancreas Transplantation | 1991 |
Metabolic characteristics in patients with long-term pancreas graft with systemic or portal venous drainage.
Between January 1983 and June 1990, 32 simultaneous pancreas and kidney transplantations were performed at the University of Barcelona. Insulin-secretion was assessed by intravenous glucose tolerance test performed 24h after transplantation and oral glucose tolerance test during the follow-up. Insulin secretion was also studied in seven non-diabetic patients with kidney transplants. Insulin levels in patients with pancreas and kidney transplantations both at the basal level and after glucose stimulation were higher than normal but not different than those observed in patients with kidney transplantation only. Patients with both pancreas and kidney transplantations and kidney transplantation only presented a mild insulin resistance, measured by the glucose/insulin ratio. Insulin levels during the follow-up of a patient with portal venous drainage were similar to those observed in patients with systemic venous drainage. In conclusion, pancreas transplantation allows a long-term maintenance of glucose homeostasis, although coexisting with an insulin resistance, probably related of the immunosuppressive therapy. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Male; Pancreas Transplantation; Portal Vein; Reference Values; Retrospective Studies | 1991 |
Time-related, cross-sectional and prospective follow-up of pancreatic endocrine function after pancreas allograft transplantation in type 1 (insulin-dependent) diabetic patients.
It has been established that successful pancreas transplantation in Type 1 (insulin-dependent) diabetic patients results in normal but exaggerated phasic glucose-induced insulin secretion, normal intravenous glucose disappearance rates, improved glucose recovery from insulin-induced hypoglycaemia, improved glucagon secretion during insulin-induced hypoglycaemia, but no alterations in pancreatic polypeptide responses to hypoglycaemia. However, previous reports have not segregated the data in terms of the length of time following successful transplantation and very little prospective data collected over time in individual patients has been published. This article reports that in general there are no significant differences in the level of improvement when comparing responses as early as three months post-operatively up to as long as two years post-operatively when examining the data cross-sectionally in patients who have successfully maintained their allografts. Moreover, this remarkable constancy in pancreatic islet function is also seen in a smaller group of patients who have been examined prospectively at various intervals post-operatively. It is concluded that successful pancreas transplantation results in remarkable improvements in Alpha and Beta cell but not PP cell function that are maintained for at least one to two years. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucagon; Glucose; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Pancreas Transplantation; Prospective Studies; Transplantation, Homologous | 1991 |
Long-term metabolic control in recipients of combined pancreas and kidney transplants.
Metabolic glucose control was followed in 36 patients at 12-month intervals for up to 5 years after a successful combined kidney and segmental duct-occluded pancreas transplantation. All recipients had normal blood glucose levels at each examination. HbA1 values, intravenous glucose tolerance test, C-peptide levels and C-peptide responses to glucagon stimulation were also, on average, within the normal range. Several individual patients had, however, abnormal values for these parameters. At most 46% had abnormal values for HbA1 and intravenous glucose tolerance test, up to 13% showed low C-peptide values and up to 46% of the stimulated C-peptide responses were inadequate at the different intervals. These parameters did not deteriorate with time. This was true both for the whole group of patients as well as for the 6 patients with a 5-year observation time evaluated separately. Despite these abnormalities in glucose metabolism, all patients remained normoglycaemic without need for exogenous insulin up to 5 years after transplantation. The long-term ability of duct-occluded segmental pancreatic grafts to preserve euglycaemia therefore seems to remain intact at least for 5 years. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Immunosuppressive Agents; Kidney Transplantation; Pancreas Transplantation; Reference Values; Uremia | 1991 |
Insulin action and insulin binding following pancreas transplantation.
Insulin action and insulin specific binding to erythrocytes were examined in ten recipients of a pancreatic segment and renal graft (Group 1), in nine non-diabetic kidney recipients (Group 2) and in ten age- and weight-matched healthy control subjects (Group 3). All transplant recipients were normoglycaemic without need of insulin, received the same immunosuppression and had good renal graft function at 11-18 months post-transplantation, when the investigation was performed. Using the insulin clamp technique, insulin action was expressed as the metabolic clearance rate of glucose at insulin infusion rates of 1.0 (MCRsubmax) and 10.0 (MCRmax) mU.kg-1.min-1. In comparison with the healthy control subjects, fasting free insulin and C-peptide levels were significantly higher in Groups 1 and 2, but no differences between Groups 1 and 2 were found (p greater than 0.05). Mean values +/- SEM of MCRsubmax in Groups 1, 2 and 3 were 6.30 +/- 0.55, 6.09 +/- 0.69 and 10.52 +/- 1.10 ml.kg-1.min-1 respectively, and of MCRmax 12.65 +/- 0.78, 13.14 +/- 0.92 and 19.28 +/- 1.42 ml.kg-1.min-1 respectively. Insulin action was significantly decreased in Groups 1 and 2 at the low as well as the high insulin infusion rates but there was no difference between the two groups of recipients (p greater than 0.05). No differences in binding data (specific binding, number of binding sites per cell) were found. It is concluded that insulin resistance is common to all immunosuppressed organ recipient and is not related to the pancreas graft. The decrease maximal response to insulin and normal insulin binding to erythrocytes tend to suggest a post-receptor defect in insulin action. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Erythrocytes; Female; Humans; Insulin; Kidney Transplantation; Kinetics; Male; Pancreas Transplantation; Receptor, Insulin; Reference Values | 1991 |
Consequences of systemic venous drainage and denervation of heterotopic pancreatic transplants for insulin/C-peptide profiles in the basal state and after oral glucose.
Plasma glucose, immunoreactive insulin and C-peptide concentrations were compared in nine pancreas-kidney-transplanted patients (systemic venous drainage) and in ten non-diabetic kidney-transplanted patients with similar kidney function. In the basal state, C-peptide (insulin secretion) was similar, but immunoreactive insulin was higher and glucose concentrations were slightly, but significantly lower in pancrease-transplanted patients. After 50 g oral glucose, the plasma glucose and IR-insulin profiles were similar in both groups. The circumvention of first-pass hepatic insulin extraction (decreased endogenous insulin clearance) was compensated for by a significant reduction in insulin secretion (C-peptide; p = 0.036). In conclusion, hyperinsulinaemia in pancreas-transplanted patients with systemic venous drainage is significant only in the basal state. Insulin delivered into the portal and peripheral circulation, when leading to similar insulin profiles, maintains comparable degrees of glucose tolerance. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucose Tolerance Test; Humans; Insulin; Kidney Transplantation; Pancreas Transplantation; Reference Values; Transplantation, Heterotopic; Veins | 1991 |
The 5' insulin gene polymorphism and the genetics of vascular complications in type 1 (insulin-dependent) diabetes mellitus.
Recent data suggest genetic contributions to the microvascular complications of Type 1 (insulin-dependent) diabetes mellitus. Most research has focused on the HLA region, and the potential role of other genetic loci has not been adequately explored. We examined the possible relationship between DNA polymorphisms in the region 5' to the insulin gene on chromosome 11 and diabetic nephropathy. This was done by comparison of those diabetic patients homozygous for class 1 alleles at the 5' insulin gene polymorphism locus to 1/3 heterozygotes in a well-characterized series of 324 insulin-requiring diabetic patients from the Wisconsin Epidemiologic Study of Diabetic Retinopathy. Proteinuria (defined as greater than or equal to 0.3 g protein/l urine), was used as suggestive evidence for diabetic nephropathy. Hypertension, a frequent associated finding in diabetic patients with nephropathy, was defined as a blood pressure greater than 140/90 or a history of previous treatment of hypertension. The two genotypically defined groups did not differ from each other in regard to sex ratio, age at diagnosis, age at examination, duration of diabetes, body mass, HbAlc or C-peptide. The 1+1 group had a higher prevalence of proteinuria, 29% as compared to 16.2% in other genotypes (p less than 0.05). There was no significant difference in the frequency of hypertension between the two genotypic groups. This finding suggests that the 5' insulin gene polymorphism may be associated with risk for nephropathy, but the pathophysiologic mechanism remains unclear. Topics: Blood Pressure; C-Peptide; Chromosome Mapping; Chromosomes, Human, Pair 11; Cohort Studies; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Retinopathy; Female; Genes; Glycated Hemoglobin; Humans; Hypertension; Insulin; Male; Polymorphism, Genetic; Proteinuria; Sex Characteristics | 1991 |
Remission of insulin requirement in late secondary failure to oral hypoglycemic agents (IRD): results at 24 months and analysis of predictive factors.
Over the last four years, we have done a prospective study of insulin requiring diabetes (IRD). We offered 59 patients insulin therapy during 10 to 14 days by means of continuous subcutaneous insulin injection with the help of a pump in order to maintain the patient under oral hypoglycemic agents (OHA). We divided our population into two characteristic groups and isolated parameters that were predictive of post-insulin therapy evolution by means of C peptide assays. In one group, in 50% of cases, endogenous insulin production appeared impaired and could not be restored by insulin therapy. The patients in this group suffered a renewed drug failure within 3 months. In the other group, 50% of cases, endogenous insulin production was preserved and the CP/blood glucose level ratio improved. On insulin treatment interruption, we observed a significantly improved fasting blood glucose level and we observed decreased insulin needs. The patients, who were probably insulin resistant, suffered only late failures or went into remission, often for longer than one year. The data bring us to the logical conclusion of IRD heterogeneity. Only some of these patients can benefit from temporary insulin therapy and the remission attempt should be limited to them. Topics: Biomarkers; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Hypoglycemic Agents; Insulin Infusion Systems; Male; Middle Aged; Obesity; Prognosis; Prospective Studies; Treatment Outcome | 1991 |
Urinary C-peptide as an index of unstable glycemic control in insulin-dependent diabetes mellitus (IDDM)
In order to investigate whether urinary C-peptide (UCP) excretion can be a useful index of insulin-dependent diabetes mellitus (IDDM) with unstable glycemic control, UCP was measured in nine IDDM patients with unstable glycemic control, nine IDDM patients with stable glycemic control, and 12 non-insulin-dependent diabetic (NIDDM) patients treated with insulin. The UCPs in overnight urine (U1) and fasting single void urine (U2) in IDDM patients with unstable glycemic control were significantly lower than those in IDDM patients with stable glycemic control (U1: 0.03 +/- 0.03 vs 0.24 +/- 0.20 nmol/mmol-Creatinine, U2: 0.02 +/- 0.01 vs 0.20 +/- 0.20 nmol/mmol-Cr, mean +/- SD, both P less than 0.01). The UCPs in U1 and U2 in both groups of IDDM were significantly lower than those in NIDDM (U1: 0.97 +/- 0.52, U2: 0.73 +/- 0.41 nmol/mmol-Cr, both P less than 0.01). The UCPs in U1 and U2 significantly correlated with incremental C-peptide response to intravenous glucagon injection and with glycemic stability assessed by the standard deviation of 10 previous fasting plasma glucose levels. These results suggest that UCP reflects their residual insulin secretory capacity and that UCP can be a useful index which distinguishes patients with unstable IDDM from those with stable diabetes mellitus. Topics: Adult; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Middle Aged | 1991 |
Nocturnal electroencephalogram registrations in type 1 (insulin-dependent) diabetic patients with hypoglycaemia.
Eight Type 1 (insulin-dependent) diabetic patients with no diabetic complications were studied overnight for two consecutive and one subsequent night with continuous monitoring of electroencephalogram and serial hormone measurements. The aims were: 1) to evaluate the influence of spontaneous and insulin-induced hypoglycaemia on nocturnal electroencephalogram sleep-patterns and, 2) to evaluate counter-regulatory hormone responses. Spontaneous hypoglycaemia occurred on six nights (38%) with blood glucose concentrations less than 3.0 mmol/l and on four nights less than 2.0 mmol/l. All the patients experienced insulin-induced hypoglycaemia with a blood glucose nadir of 1.6 (range 1.4-1.9) mmol/l. The electroencephalogram was analysed by a new method developed for this purpose in contrast to the traditional definition of delta-, theta-, alpha- and beta-activity. The blood glucose concentration could be correlated to the rank of individual electroencephalogram-patterns during the whole night, and specific hypoglycaemic amplitude-frequency patterns could be assigned. Three of the eight patients showed electroencephalogram changes at blood glucose levels below 2.0 (1.6-2.0) mmol/l. The electroencephalogram classes representing hypoglycaemic activity had peak frequencies at 4 and 6 Hz, respectively, clearly different from the patients' delta- and theta-activity. The changes were not identical in each patient, however, they were reproducible in each patient. The changes were found equally in all regions of the brain. The three patients with electroencephalogram changes during nocturnal hypoglycaemia could only be separated from the other five patients by their impaired glucagon responses. Against this background the possibility of protection by glucagon, against neurophysiologic changes in the brain during hypoglycaemia may be considered. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Electrocardiography; Electroencephalography; Epinephrine; Glucagon; Glycated Hemoglobin; Growth Hormone; Humans; Hydrocortisone; Hypoglycemia; Insulin Antibodies; Norepinephrine | 1991 |
Studies of the isolation and transplantation of purified islets in adult humans.
Topics: Adult; Blood Glucose; C-Peptide; Cell Separation; Centrifugation, Density Gradient; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Immunosuppression Therapy; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation | 1991 |
Intraportal islet allografts: the use of a stimulation index to represent functional results.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Islets of Langerhans Transplantation; Kidney Transplantation; Models, Theoretical; Portal System; Transplantation, Homologous | 1991 |
Effects of glucagon on free fatty acid metabolism in humans.
To determine whether physiological changes in plasma glucagon concentrations are important in regulating basal adipose tissue lipolysis, FFA flux ([1-14C]palmitate) was measured in response to increases and decreases in plasma glucagon. Eight volunteers with insulin-dependent diabetes mellitus (IDDM) and nine healthy nondiabetic volunteers were studied using the pancreatic clamp technique to control plasma insulin, GH, and glucagon concentrations at desired levels. Palmitate flux at the chosen euglucagonemic hormone infusion rates was similar to baseline values (1.73 +/- 0.12 vs. 1.75 +/- 0.23 and 1.35 +/- 0.18 vs. 1.35 +/- 0.16 mumol/kg.min, respectively, in IDDM and nondiabetic subjects). No significant changes in palmitate flux occurred in response to glucagon withdrawal or mild (nondiabetic volunteers) or high physiological (IDDM volunteers) hyperglucagonemia. Thus, under conditions of normal FFA availability, changes in plasma glucagon concentrations within the physiological range have little or no effect on adipose tissue lipolysis. Topics: Adipose Tissue; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Growth Hormone; Humans; Hydrocortisone; Insulin; Kinetics; Lipolysis; Male; Palmitic Acid; Palmitic Acids | 1991 |
Factors predicting residual beta-cell function in the first year after diagnosis of childhood type 1 diabetes.
Twenty-five children aged 2-14 years (mean age 8.39 +/- 0.78 years) were studied prospectively during the first year after the diagnosis of type 1 diabetes. Of their clinical and metabolic features at diagnosis, only age showed a significant independent relationship with endogenous C-peptide production during the first year. Age was correlated with higher values for basal and stimulated plasma C-peptide at 7-14 days after diagnosis, at 6 months and at 12 months. At diagnosis, age was also associated with a higher value for HbA1c and a lower prevalence of insulin antibodies. C-peptide production peaked at 3 months and thereafter declined. Mean HbA1c and insulin requirement were both minimal at 6 months. At diagnosis, there were significant inverse relationships between basal C-peptide production and both insulin dose and HbA1c and between stimulated C-peptide production and HbA1c. Basal and stimulated C-peptide production were inversely related to insulin dose at 6 and 12 months. Stimulated C-peptide was higher at 12 months in children retaining islet cell antibodies. These findings confirm the importance of age as a predictor of residual beta-cell function in type 1 diabetes and indicate that older children present clinically following a slower course of beta cell destruction. Topics: Adolescent; Age Factors; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infant; Insulin; Insulin Antibodies; Islets of Langerhans; Longitudinal Studies; Male; Prospective Studies | 1991 |
Endocrine-metabolic function in remission-phase IDDM during administration of cyclosporine.
We have studied the endocrine-metabolic status of patients in non-insulin-receiving (NIR) remission of insulin-dependent diabetes mellitus (IDDM) within 6-60 mo of diagnosis during administration of cyclosporine, in comparison with nondiabetic subjects. IDDM patients in NIR remission were recognized when target glycemic control (plasma glucose and mean capillary blood glucose levels less than 7.8 mM before meals) was maintained without administration of insulin for at least 2 wk. In so-called isoglycemic tests, 50 g glucose was administered orally, and the glycemic curve was simulated in a subsequent study by programmed intravenous infusion of glucose. Under these conditions, the subjects with diabetes exhibited obvious glucose intolerance: acute beta-cell responses to intravenous glucose were virtually absent but significant, although subnormal responses were present after oral glucose. The responses of plasma immunoreactive gastric inhibitory polypeptide to oral glucose were normal. After bolus intravenous injections of glucose, the patients with diabetes again exhibited glucose intolerance; acute responses of immunoreactive insulin (IRI) and C-peptide were present, although grossly obtunded. On intravenous infusion of arginine (30 g in 30 min), the patients with diabetes showed substantial but subnormal increases in plasma IRI and C-peptide. Intravenous infusion of arginine elicited increments of plasma immunoreactive glucagon (IRGI) in both groups, and this response was slightly exaggerated in the patients with diabetes. On ingestion of a standard mixed meal (Sustacal) delivering 600 cal, there was a modest but significantly greater increase in plasma glucose levels in the diabetic subjects.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Arginine; Blood Glucose; C-Peptide; Child; Cyclosporins; Diabetes Mellitus, Type 1; Eating; Female; Gastric Inhibitory Polypeptide; Glucagon; Glucose Tolerance Test; Humans; Male; Reference Values | 1991 |
The effect of acute hyperglycemia on the plasma C-peptide response to intravenous glucagon or to a mixed meal in insulin-dependent diabetes mellitus.
The dose-response relationships between prestimulatory blood glucose concentration and the plasma C-peptide responses to stimulation with 1 mg of glucagon iv or a standard mixed meal were studied in 8 C-peptide positive patients with insulin-dependent diabetes mellitus. Hyperglycemia was maintained for 90 min before stimulation using a hyperglycemic clamp technique. Each test was performed at the steady state blood glucose levels approximately 5, approximately 12, and approximately 20 mmol/l. The glucose potentiation of the incremental plasma C-peptide area under the curve at the two levels of hyperglycemia in percent of the area at normoglycemia (median and range) was 343% (53-1053) (p less than 0.05) and 341% (267-1027) (p less than 0.05) after glucagon and 140% (76-227) (NS) and 251% (95-1700) (p less than 0.05) after the meal. The corresponding relative glucose potentiation of plasma C-peptide 6 min after stimulation with glucagon was 124% (100-427) (p less than 0.02) and 144% (100-209) (p less than 0.05). There was no significant difference in the degree of glucose potentiation at approximately 12 or approximately 20 mmol/l. Furthermore, there was no significant difference in the degree of glucose potentiation of the different estimated values of B-cell function. In conclusion, the plasma C-peptide responses to iv glucagon or to a standard test meal were markedly potentiated by acute hyperglycemia in insulin-dependent diabetes mellitus. No further potentiation was, however, obtained when the prestimulatory blood glucose concentration was raised above 12 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Acute Disease; Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Food; Glucagon; Humans; Hyperglycemia; Injections, Intravenous; Islets of Langerhans; Male | 1991 |
Metabolic characteristics of autoimmune diabetes mellitus in adults.
It is still a matter of debate whether patients who develop islet-cell antibody positive autoimmune diabetes during adulthood represent slowly evolving Type 1 (insulin-dependent) diabetes mellitus or a separate subgroup of Type 2 (non-insulin-dependent) diabetes. To address this question, we measured C-peptide response to a test meal, and energy metabolism in the basal state and during a euglycaemic, hyperinsulinaemic clamp in (1) 29 patients with Type 2 diabetes; (2) 10 patients with autoimmune diabetes developing after the age of 40 years; (3) 11 patients with Type 1 diabetes and (4) 15 non-diabetic control subjects. While C-peptide response to a test meal was lacking in Type 1 diabetes and nearly normal in Type 2 diabetes, the C-peptide response in autoimmune diabetes was markedly reduced. Patients with Type 2 diabetes, autoimmune diabetes and Type 1 diabetes showed a 47%, 45% and 42%, respectively, reduction in the rate of non-oxidative glucose metabolism compared with control subjects (p less than 0.05-0.01). Similarly, patients with Type 2 diabetes (+52%), autoimmune diabetes (+27%) and Type 1 diabetes (+33%) presented with an enhanced basal rate of hepatic glucose production, which was less suppressed by insulin compared with healthy control subjects (p less than 0.01). However, patients with autoimmune diabetes derived more energy from oxidation of glucose and proteins and less energy from oxidation of lipids than patients with either Type 1 or Type 2 diabetes (p less than 0.05-0.01). In conclusion, patients who develop autoimmune diabetes during adulthood share the defects in hepatic glucose production and in non-oxidative glucose metabolism with both Type 1 and Type 2 diabetes.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Autoantibodies; Autoimmune Diseases; Blood Glucose; C-Peptide; Cholesterol; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Eating; Female; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Middle Aged; Thyroid Gland; Thyroxine; Triglycerides | 1991 |
Basal and stimulated plasma levels of pancreatic amylin indicate its co-secretion with insulin in humans.
Amylin is a 37-amino acid pancreatic polypeptide, probably involved in the pathophysiology of Type 2 (non-insulin-dependent) diabetes mellitus. We have determined amylin in human plasma by extraction-based radioimmunoassay (Sep-Pak C18). Of 23 healthy control subjects plasma amylin was determined as 11.9 +/- 3.5 ng/l. Of 27 patients with Type 2 diabetes receiving insulin the amylin levels were lower, and in 16 patients with Type 2 diabetes on oral medication they were higher than in the control subjects; 8.2 +/- 4.4 ng/l (p less than 0.01) vs 18.8 +/- 9.9 ng/l (p less than 0.05). In 14 Type 1 (insulin-dependent) diabetic patients we found extremely low mean amounts of amylin: 2.9 +/- 1.9 ng/l (p less than 0.002). Thus, basal amylin appears to be associated with the capacity to release insulin. An oral glucose load stimulated the release of amylin, this was more pronounced in patients with Type 2 diabetes than in healthy subjects. An excellent correlation of mean amylin with mean insulin concentrations was obtained (r = 0.949). In patients with Type 2 diabetes amylin was reduced congruent to decreases in C-peptide during a hyperinsulinaemic, euglycaemic glucose clamp experiment (r = 0.971 for linear correlation between C-peptide levels and amylin). We conclude, that amylin and insulin are co-secreted in humans, and that the amylin release is under feedback-control by insulin. Topics: Adult; Amyloid; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose; Humans; Insulin; Insulin Secretion; Islet Amyloid Polypeptide; Islets of Langerhans; Kinetics; Middle Aged; Reference Values; Time Factors | 1991 |
Urinary C-peptide excretion in pancreas transplantation with urinary drainage.
Topics: Adult; Amylases; C-Peptide; Diabetes Mellitus, Type 1; Drainage; Follow-Up Studies; Humans; Kidney Transplantation; Pancreas Transplantation; Reference Values; Urinary Diversion | 1990 |
Islet hormonal regulation of glucose turnover during exercise in type 1 diabetes.
A decline in plasma insulin and an increase in glucagon are known to occur during intense and/or prolonged exercise. However, it is not established whether changes in insulin and glucagon secretion are involved in the precise matching of hepatic glucose production to the enhanced glucose uptake by muscle during brief, low intensity exercise. We studied the effects of 30-min cycle exercise at 40% of maximal aerobic capacity in healthy subjects and C-peptide-deficient subjects with type 1 diabetes (IDDM) using [3-3H]glucose to estimate glucose turnover. Diabetic subjects were studied during continuous iv insulin infusion, which normalized glucose kinetics before experimental perturbations. In control (saline-infused) experiments, endogenous glucose appearance (Ra) increased by 80-90% above baseline to match the increase in glucose disappearance in both normal and IDDM subjects, even though the latter exercised at fixed levels of plasma free insulin, averaging 203 +/- 19 pmol/L. In other experiments, somatostatin was infused, and glucagon (1.0 ng/kg.min) and insulin (at two different rates) were maintained at constant levels. Infusion of insulin in normal subjects at doses sufficient to maintain constant peripheral plasma insulin was associated with no apparent effect on glucose turnover (plasma insulin, 80 +/- 21 pmol/L, compared to 52 +/- 5 pmol/L during saline; P = NS). However, insulin infusion at doses that normalized the portal insulin concentration (approximately 208 pmol/L) together with glucagon replacement inhibited the rise in glucose production in both normal and IDDM subjects. There were similar 45-55% reductions (P less than 0.03) of the increase in Ra seen with exercise in control experiments. When peripheral plasma free insulin (and presumably portal levels as well) were increased by about 20% in this experimental setting in IDDM (278 +/- 43 pmol/L), the suppression of Ra was even more profound, and Ra failed to increase at all with exercise. We conclude that the hormonal regulation of Ra in brief duration exercise in man does not necessitate the decrements in portal venous insulin observed under more intense exercise conditions as long as an exercise-induced glucagon secretory response can occur. Glucagon secretion alone cannot prevent hypoglycemia when portal venous insulin concentrations are increased by minimal amounts, such as in insulin-treated diabetics. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Exercise; Female; Glucagon; Glucose; Homeostasis; Humans; Insulin; Insulin Infusion Systems; Islets of Langerhans; Male; Norepinephrine; Somatostatin | 1990 |
Lack of effect of hyperglycemia on lipolysis in humans.
Controversy exists regarding whether plasma glucose concentrations are independently involved in the regulation of adipose tissue lipolysis. In the present study, six subjects with insulin-dependent diabetes and six nondiabetic volunteers were studied during infusion of somatostatin, growth hormone, and insulin at rates designed to maintain basal rates of lipolysis, which was traced using a constant infusion of [1-14C]palmitate. A euglycemic (approximately 5 mmol/l) clamp was performed for 3 h, followed by 3 h of hyperglycemia (approximately 9 and approximately 11 mmol/l in nondiabetic and diabetic subjects, respectively). Ten nondiabetic subjects were studied during 6 h of euglycemia to exclude time-dependent changes in lipolysis. The results showed that palmitate concentrations did not change between euglycemia and hyperglycemia in either group [118 +/- 10 vs. 132 +/- 14 mumol/l and 145 +/- 21 vs. 134 +/- 15 mumol/l in nondiabetic and diabetic subjects, respectively; both P = not significant (NS)]. Similarly, palmitate rate of appearance (Ra) did not change during hyperglycemia (1.0 +/- 0.1 and 1.7 +/- 0.4 mumol.kg-1.min-1 in nondiabetic and diabetic subjects, respectively) compared with euglycemia (1.0 +/- 0.1 and 1.6 +/- 0.4 mumol.kg-1.min-1 in nondiabetic and diabetic subjects, respectively; P = NS). Palmitate concentrations and Ra did not change during 6 h of euglycemia in nondiabetic volunteers. Thus hyperglycemia per se has no effect on free fatty acid turnover. Changes in lipolysis that occur coincident with hyperglycemia are probably due to changes in other circulating substrates or hormones known to affect lipolysis. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glycated Hemoglobin; Growth Hormone; Humans; Hydrocortisone; Hyperglycemia; Insulin; Lipolysis; Male; Palmitic Acid; Palmitic Acids; Reference Values; Somatostatin | 1990 |
Diurnal variation of blood ketone bodies in insulin-dependent diabetes mellitus and noninsulin-dependent diabetes mellitus patients: the relationship to serum C-peptide immunoreactivity and free insulin.
We examined whether the rise in ketone body concentration around midnight and in the early morning was due to the lack of free insulin (IRI) or excess of insulin counterregulatory hormones such as human growth hormone (hGH), cortisol and glucagon in noninsulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM) patients and whether the monitoring of blood ketone body concentration was clinically useful as an index of metabolic control for deciding to increase or decrease the insulin dose in the treatment of diabetes mellitus. Serum levels of 3-hydroxybutyrate (3-OHBA), acetoacetate (AcAc) and 3-OHBA/AcAc ratio before breakfast were significantly increased in insulin-treated NIDDM patients with well-controlled fasting plasma glucose levels and IDDM patients compared to those in normal subjects. Mirror image diurnal changes were found between serum concentrations of 3-OHBA and serum C-peptide or free IRI in normal subjects and NIDDM patients treated with diet alone or sulfonylurea during the 24-hour daily profiles. However, there were no correlations between 3-OHBA and free IRI in the NIDDM patients treated with insulin and IDDM patients who had a much larger increase in the mean concentration of serum 3-OHBA at 6 a.m. caused by a low concentration of free IRI. Counterregulatory hormones were not increased in IDDM patients compared to normal subjects in the early morning. Cortisol/free IRI and hGH/free IRI molar ratios were significantly increased in NIDDM and IDDM patients compared to normal subjects in the early morning, but glucagon/free IRI molar ratio was not changed between IDDM and normal subjects. In conclusion, the early morning rising of ketone body concentration in insulin-treated diabetic patients, particularly IDDM patients, is due to the absolute lack of free IRI and/or the relative lack of free IRI to the levels of hGH or cortisol, and the monitoring of 3-OHBA is clinically useful as a more sensitive index of metabolic control. Topics: 3-Hydroxybutyric Acid; Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids, Nonesterified; Humans; Hydroxybutyrates; Insulin; Ketone Bodies; Middle Aged; Time Factors | 1990 |
Sustained oscillatory insulin secretion after pancreas transplantation.
Topics: Activity Cycles; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose; Humans; Infusions, Intravenous; Insulin; Insulin Secretion; Islets of Langerhans Transplantation; Kidney Transplantation; Male | 1990 |
[Clinical significance of plasma C-peptide analysis and the analytical method in the diagnosis of diabetes related diseases].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Glucagon; Humans; Hyperinsulinism; Hypoglycemia; Insulin; Insulin Secretion; Islets of Langerhans; Radioimmunoassay; Reference Values | 1990 |
[clinical significance of urinary C-peptide in the diagnosis of diabetes mellitus].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Insulin; Insulin Secretion; Kidney; Radioimmunoassay | 1990 |
Insulin independence after islet transplantation into type I diabetic patient.
Effective clinical trials of islet transplantation have been limited by the inability to transplant enough viable human islets into patients with type I (insulin-dependent) diabetes mellitus to eliminate their exogenous insulin requirement. We report the first type I diabetic patient with an established kidney transplant on basal cyclosporin immunosuppression who was able to eliminate the insulin requirement after human islet transplantation into the portal vein. We successfully isolated approximately 800,000 islets that were 95% pure from 1.4 cadaver pancreases containing 121 U of insulin. Islets were proven viable by in vitro insulin response to glucose challenge. After 7 days of 24 degrees C culture, the islets were transplanted into the portal vein under local anesthesia. Seven days of Minnesota antilymphoblast globulin (20 mg/kg) administration followed the islet transplantation, with maintenance of the cyclosporin. Blood glucose was kept under strict control via intravenous insulin for 10 days posttransplantation, when all insulin therapy was stopped. Off insulin, the average 24-h blood glucose level remained less than 150 mg/dl, with the fasting glucose level at 115 +/- 6 mg/dl and the 2-h postprandial level at 141 +/- 8 mg/dl for 22 days posttransplantation (the time of this study). The C-peptide values post-Sustacal testing, although initially rising slower, exceeded the normal range, with peak values of 1.0-1.8 pmol/ml. This preliminary result represents the first essential step required to determine the feasibility of islet transplantation by future clinical trials. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Kidney Transplantation; Transplantation, Homologous | 1990 |
The clinical and hormonal (C-peptide and glucagon) profile and liability to ketoacidosis during nutritional rehabilitation in Ethiopian patients with malnutrition-related diabetes mellitus.
Cases of malnutrition-related diabetes mellitus conforming to the description of the protein deficient pancreatic diabetes type in Ethiopian patients were compared with Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic. Fourteen of 39 malnutrition-related diabetes mellitus patients had fat malabsorption compared with only two of ten Type 1 diabetic patients and one of nine control subjects. Xylose absorption was normal favouring a pancreatic cause for the malabsorption. Plasma C-peptide during oral glucose tolerance test was significantly lower than that in Type 2 diabetic patients and normal control subjects (p less than 0.01 to 0.001) and was also consistently but not significantly higher than in Type 1 diabetic patients. Glucagon secretion patterns were similar in malnutrition-related and Type 1 diabetic patients. Of 23 new malnutrition-related diabetic patients treated with glibenclamide after nutritional rehabilitation and insulin treatment, only three responded, 14 were unresponsive but remained ketosis free for over eight days while another six developed ketoacidosis or significant ketonuria within two to six days during the trial. Sixteen unselected Type 1 diabetic patients who discontinued their insulin therapy all developed frank ketoacidosis after a mean of 5.5 days. The similarity of the malnutrition-related and Type 1 diabetes mellitus in age of onset, insulin requirement for diabetic control and appearance of ketosis-proneness in some cases, together with the similarity of C-peptide and glucagon secretion patterns suggest that the protein deficient pancreatic diabetes variant of malnutrition-related diabetes mellitus may be Type 1 diabetes mellitus modified by the background of malnutrition rather than an aetiologically separate entity.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Ethiopia; Female; Glucagon; Humans; Male; Middle Aged; Nutritional Physiological Phenomena; Protein-Energy Malnutrition; Reference Values | 1990 |
Effects of improved blood glucose on insulin-induced hypoglycaemia, TRH, GnRH and exercise tests in insulin-dependent diabetes.
In order to evaluate effects of metabolic control on pituitary function in insulin-dependent diabetes exercise, hypoglycaemia (insulin tolerance test), thyrotrophin releasing hormone and gonadotrophin releasing hormone, tests were performed on 25 patients before (Study 1) and after 2 weeks of improved metabolic control (Study 2). Patients were sub-divided into C-peptide negative (CpN, 10 patients with no residual C-peptide secretion) and C-peptide positive (CpP, 15 patients with residual beta-cell function) groups for analysis of results. Exercise induced higher growth hormone responses in CpN patients independent of metabolic control (P less than 0.001). Thyrotrophin releasing hormone induced higher growth hormone responses in CpN patients; this response was threefold greater after improved control (P less than 0.005). Growth hormone and cortisol response to hypoglycaemia and thyroid stimulating hormone and prolactin secretion in response to thyrotrophin releasing hormone were unaffected by residual beta-cell function or metabolic control. Luteinizing hormone response to gonadotrophin releasing hormone in CpN patients was impaired and lower after improved control (P less than 0.002). The results indicate an association between residual pancreatic insulin secretory and hypothalamic/pituitary function, possibly reflecting central neurosecretion of insulin. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Exercise Test; Female; Follicle Stimulating Hormone; Humans; Hypoglycemia; Insulin; Luteinizing Hormone; Male; Pituitary Hormone-Releasing Hormones; Prolactin; Thyrotropin; Thyrotropin-Releasing Hormone | 1990 |
Assessment of the factors influencing successful clinical islet transplantation.
Topics: C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Fetus; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation | 1990 |
Comparison of children with type 1 (insulin-dependent) diabetes in northern Finland and southern Ontario: differences at disease onset.
This study was undertaken to evaluate whether differences in Type 1 diabetes incidence in two separate geographical locations are associated with any differences in biochemical and immunological features at the onset of the disease. We studied all children under 16 years of age who presented at the time of diagnosis with Type 1 diabetes to the children's hospitals in Oulu (n = 43) and Toronto (n = 87) during 1984-1985. At onset children from Northern Finland had lower blood glucose and HbAlc levels, and higher C-peptide concentrations than those from Southern Ontario (p's less than 0.01). The group from Northern Finland also had a higher incidence of multiplex families (18.6 vs 4.6%, p less than 0.01). Amongst the Finnish group, those from multiplex families had a higher C-peptide concentration and lower frequency of ketoacidosis than those from simplex families (p's less than 0.05). Thus differences do exist at the onset of diabetes in these groups from geographical locations with greatly different incidences of Type 1 diabetes. Topics: Adolescent; Age Factors; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Finland; Glycated Hemoglobin; Humans; Hydrogen-Ion Concentration; Incidence; Infant; Infant, Newborn; Ontario | 1990 |
Insulin resistance in type 1 (insulin-dependent) diabetes: dissimilarities for glucose and intermediary metabolites.
To study insulin action on intermediary metabolism in relation to glucose disposal in Type 1 (insulin-dependent) diabetes, 29 patients and 15 control subjects underwent sequential euglycemic clamps (insulin infusion rates 0.5, 1.0, 2.0 and 5.0 mU.kg-1.min-1 in 2 hour periods). Dose-response curves were constructed for insulin-stimulated glucose disposal. Metabolite profiles were determined in the basal state, and during submaximal (+/- 80 mU/l) and maximal (greater than 500 mU/l) insulinaemia. For at least 11 hours preceding the study, blood glucose levels were maintained between 4 and 10 mmol/l in the patients. In the basal state, when at matched glycemia hepatic glucose production is known to be similar in patients and control subjects, glucose, glycerol, free fatty acids and glucagon were comparable, whereas differences were found for alanine (-29%, diabetic vs. control subjects), lactate (-24%), acetoacetate (+270%), 3-hydroxybutyrate (+260%) and insulin (+210%; all p less than 0.02). At submaximal (+/- 80 mU/l) and maximal (greater than 500 mU/l) insulin levels, metabolite levels were comparable, except alanine (-20% diabetic vs. control subjects, p less than 0.001). Glucose disposal rates, however, were decreased in patients at submaximal insulin levels (ED50 73 +/- 10 vs. 54 +/- 4 mU/l in control subjects, p less than 0.01 whereas maximal glucose disposal was similar (61 +/- 3 vs. 65 +/- 3 mumol.kg-1.min-1). In conclusion, in Type 1 diabetes: (a) changes in basal levels of intermediary metabolites were present, despite 11 hours of antecedent euglycemia; (b) in contrast to glucose disposal at submaximal insulinaemia, no major difference existed in insulin's efficacy on intermediary metabolism. Topics: Adult; Blood Glucose; Body Mass Index; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glucose Clamp Technique; Glycated Hemoglobin; Glycerol; Humans; Insulin; Insulin Antibodies; Insulin Resistance; Ketone Bodies; Male; Reference Values | 1990 |
Relationship between insulin antibodies and metabolic control in type I diabetes mellitus.
1. The objective of the present study was to investigate whether a change in insulin therapy from bovine to purified porcine insulin would result in a decreased level of insulin antibodies (IA) in type I diabetic patients and whether there would be better metabolic control. 2. Insulin antibodies were measured by ELISA. Fifteen type I diabetic patients were prospectively followed for 8 months with monthly evaluations after changing insulin therapy from bovine to purified porcine insulin. 3. Group I patients (N = 4) had IA greater than or equal to 1.5 (value obtained by dividing the ELISA absorbance of the tested serum by the absorbance of a standard serum) at the beginning of the study. For group I patients, the modification of insulin therapy caused a 57% reduction in insulin antibody levels, and this reduction was correlated with a decrease in 24-hour glycosuria (rs = 0.66, P less than 0.001) and glycated protein (rs = 0.65, P less than 0.01). Group II patients (N = 8) had IA less than 1.5 and greater than or equal to 0.3 and group III (N = 3) had IA less than 0.3. Insulin antibody levels were unchanged during the follow-up period in both group II and group III. 4. We also studied endogenous insulin secretion, measured as fasting C-peptide, and its relationships with metabolic control and insulin antibody levels. Patients with residual insulin secretion (C-peptide greater than 60 pmol/l) showed lower levels of 24-h glycosuria, glycated protein and glycated hemoglobin. Furthermore, in this group of patients a negative correlation was found between C-peptide and insulin antibody levels (rs = -0.36, P less than 0.01). 5. We conclude that insulin antibodies could be one of the factors having a detrimental effect on metabolic control. Topics: Adolescent; Adult; Blood Glucose; Blood Proteins; C-Peptide; Child; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Glycated Hemoglobin; Glycated Serum Proteins; Glycoproteins; Glycosuria; Humans; Insulin; Insulin Antibodies; Male; Prospective Studies | 1990 |
Postprandial hyperglycaemia following a morning hypoglycaemia in type 1 diabetes mellitus.
The occurrence of hyperglycaemia following a morning hypoglycaemic episode was studied in nine patients with Type 1 diabetes. Each patient was studied twice, once following induced hypoglycaemia and once in a control study when hypoglycaemia was prevented by glucose infusion. After the initial hypoglycaemic/control period the patients were maintained on their regular insulin regimens and were given standard meals. Hypoglycaemia induced postprandial hyperglycaemia (3.1 +/- 0.8 mmol l-1 above control) which lasted for about 8 h. Maximal growth hormone levels were seen 40 min after glucose nadir (control 7.8 +/- 3.2, hypoglycaemia 74.0 +/- 12.3 mU l-1) and the magnitude of the hyperglycaemia was related to the growth hormone levels following the hypoglycaemia (r = 0.80, p less than 0.01). Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Epinephrine; Female; Glucagon; Growth Hormone; Humans; Hydrocortisone; Hyperglycemia; Hypoglycemia; Insulin; Male | 1990 |
[C-peptide assays of the urine and plasma at baseline and under stimulation with glucagon in healthy subjects and diabetics].
Urinary (CPU) and plasma C peptide values at baseline (CP0) and under stimulation with glucagon were determined in healthy subjects (n = 17) and in insulin-dependent (IDD, n = 45) and non insulin-dependent (NIDD, n = 32) diabetics. A significant difference in the parameters of insulin secretion (x? SD) was found on the one hand between the IDD group (CPU = 5.58 +/- 5.58 nmol/24 h; CP = 0.14 +/- 0.08 nmol/l; maximum C peptide value after stimulation (CPmax) = 0.33 +/- 0.31 nmol/l; C peptide delta (delta CP) = 0.14 +/- 0.14 nmol/l; area under the curve (A) = 5.00 +/- 4.84) and the NIDD group (CPU = 15.47 +/- 8.22 nmol/24 h; CP = 0.64 +/- 0.28 nmol/l; CPmax = 1.14 +/- 0.44 nmol/l; delta CP = 0.50 +/- 0.31 nmol/l; A = 17.5 +/- 5.86) and on the other hand between the IDD group and the control group (CPU = 18.20 +/- 8.40 nmol/24 h; CP = 0.41 +/- 0.11 nmol/l; CPmax = 1.00 +/- 0.31 nmol/l; delta CP = 0.69 +/- 0.20 nmol/l; A = 17.10 +/- 4.45). As regards the NIDD group, only the fasting C peptide and delta C peptide values were significantly different from those found in the control group. The significance of each parameter of insulin secretion was also studied. There was a correlation between the values of C peptidaemia before and after stimulation with glucagon. However, the correlation between plasma C peptide and urinary C peptide values was mediocre, probably because of the numerous variability factors which intervene in the urinary excretion of C peptide. Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Humans; Middle Aged; Reference Values; Stimulation, Chemical | 1990 |
Activated T-lymphocytes in newly diagnosed type I diabetic patients: relationship to residual beta cell function.
The relationship between T-lymphocyte activation and residual beta-cell function was studied in 19 newly diagnosed Type I (insulin dependent) diabetic patients, aged 6-43 years, 7-10 days after beginning insulin therapy and once normoglycemia had been achieved. Residual beta-cell function was studied by measurement of plasma C-peptide concentration 6 minutes after intravenous glucagon administration. T-lymphocyte activation markers, HLA-DR/CD3 and interleukin-2 receptor (Tac) expression, were measured in peripheral blood mononuclear cells by dual- or single-colour flow cytometry. Six patients showed increased percentages of activated T lymphocytes (increased HLA-DR positivity in four patients, and an excess of Tac-positive cells in two). The mean percentage of activated T lymphocytes was higher in patients with stimulated C-peptide levels below 300 pmol/l (8.32 +/- 1.32%) than in those with plasma stimulated C-peptide above 300 pmol/l (3.93 +/- 0.49%), P less than 0.01, or controls (3.48 +/- 0.60%), P less than 0.01. Furthermore, the six patients with increased percentages of activated T lymphocytes were in the low stimulated C-peptide group. A negative correlation was found between the percentage of activated T lymphocytes and glucagon-stimulated C-peptide (r = -0.5877, P less than 0.01). We conclude that increased T-lymphocyte activation is associated with a higher impairment of beta-cell function at the onset of Type I diabetes mellitus. Topics: Adolescent; Adult; Antigens, Differentiation, T-Lymphocyte; C-Peptide; CD3 Complex; Child; Diabetes Mellitus, Type 1; Flow Cytometry; HLA-DR Antigens; Humans; Islets of Langerhans; Lymphocyte Activation; Receptors, Antigen, T-Cell; T-Lymphocytes | 1990 |
Effects of hemipancreatectomy on insulin secretion and glucose tolerance in healthy humans.
Pancreatic tissue obtained by hemipancreatectomy from healthy living related donors has been transplanted into recipients with Type I diabetes mellitus. To determine the metabolic consequences of this procedure for the donors, we carried out oral glucose-tolerance testing and 24-hour monitoring of serum glucose levels and urinary C-peptide excretion as a measure of insulin secretion in 28 donors, both before and one year after hemipancreatectomy. The mean fasting serum glucose level was significantly higher one year after the procedure (mean +/- SD, 5.4 +/- 0.9 vs. 4.9 +/- 0.5 mmol per liter; P less than 0.003), as was the serum glucose value two hours after the administration of glucose (8.7 +/- 2.9 vs. 6.5 +/- 1.0 mmol per liter; P less than 0.001). The fasting serum insulin level was significantly lower one year after hemipancreatectomy (33.0 +/- 21.6 vs. 38.4 +/- 21.6 pmol per liter; P less than 0.05), as was the area under the insulin curves during the oral glucose-tolerance test (52,554 +/- 22,320 vs. 76,230 +/- 33,354 pmol per liter per minute; P less than 0.04). The mean 24-hour serum glucose-profile value was higher at one year, and the 24-hour urinary C-peptide excretion was lower in the 17 donors who underwent these studies. Seven of the 28 donors had abnormal glucose tolerance one year after hemipancreatectomy; however, insulin secretion in these 7 donors was indistinguishable from that in the 21 donors who had normal glucose tolerance. All 28 donors had fasting serum glucose concentrations lower than 7.8 mmol per liter, and their mean 24-hour plasma glucose levels remained within the normal range. We conclude that in healthy donors hemipancreatectomy results in a deterioration of insulin secretion and glucose tolerance, as measured one year later. Further study is required to ascertain whether the development of clinical diabetes mellitus is a risk inherent in hemipancreatectomy. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Male; Pancreas Transplantation; Pancreatectomy; Time Factors; Tissue Donors | 1990 |
[The importance of C-peptide determination in the treatment and prognosis of type II diabetes].
The concentration of C peptide which is an indicator of the secretory capacity of the beta-cells of the pancreas was assessed in 109 patients with type II diabetes, hospitalized on account of prolonged difficulties as regards compensation. The values on fasting, the maximal values after stimulation following an experimental meal and increments were greater than in age- and weight-matched controls. In diabetic patients some highly significant relationships were revealed between the C peptide concentration on fasting and indicators of the risk of ischaemic heart disease [IHD]. They included HDL cholesterol, the body mass index and uric acid. The relationship between the maximal C peptide concentration and serum sodium may be associated with a greater disposition for hypertension. Thirty-one patients with symptoms of an ischaemic myocardial lesion had a significantly elevated C peptide concentration on fasting. The increments of C peptide concentration after an alimentary stimulus correlated indirectly with indicators of the actual and long-term compensation of diabetes. In relation to the reduced increments also the need of insulin therapy was reflected. Data obtained by examination of the C peptide concentration in the blood of type II diabetics can contribute to the objectivization of needs of insulin treatment and to the detection of the link between cardiovascular risk and hyperinulinaemia. Topics: C-Peptide; Coronary Disease; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Middle Aged; Prognosis | 1990 |
Systemic venous drainage of pancreas allografts as independent cause of hyperinsulinemia in type I diabetic recipients.
To evaluate the metabolic consequences of pancreas transplantation with systemic venous drainage on beta-cell function, we examined insulin and C-peptide responses to glucose and arginine in type I (insulin-dependent) diabetic pancreas recipients (n = 30), nondiabetic kidney recipients (n = 8), and nondiabetic control subjects (n = 28). Basal insulin levels were 66 +/- 5 pM in control subjects, 204 +/- 18 pM in pancreas recipients (P less than 0.0001 vs. control), and 77 +/- 17 pM in kidney recipients. Acute insulin responses to glucose were 416 +/- 44 pM in control subjects, 763 +/- 91 pM in pancreas recipients (P less than 0.01 vs. control), and 589 +/- 113 pM in kidney recipients (NS vs. control). Basal and stimulated insulin levels in two pancreas recipients with portal venous drainage were normal. Integrated acute C-peptide responses were not statistically different (25.3 +/- 4.3 nM/min in pancreas recipients, 34.2 +/- 5.5 nM/min in kidney recipients, and 23.7 +/- 2.1 nM/min in control subjects). Similar insulin and C-peptide results were obtained with arginine stimulation, and both basal and glucose-stimulated insulin-C-peptide ratios in pancreas recipients were significantly greater than in control subjects. We conclude that recipients of pancreas allografts with systemic venous drainage have elevated basal and stimulated insulin levels and that these alterations are primarily due to alterations of first-pass hepatic insulin clearance, although insulin resistance secondary to immunosuppressive therapy (including prednisone) probably plays a contributing role. To avoid hyperinsulinemia and its possible long-term adverse consequences, transplantation of pancreas allografts into sites with portal rather than systemic venous drainage should be considered. Topics: Adult; Arginine; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Hyperinsulinism; Insulin; Islets of Langerhans; Male; Pancreas Transplantation; Portal Vein | 1990 |
Influence of polyethylene glycol (PEG) extraction on the C-peptide determination in sera from insulin-dependent diabetic patients with circulating insulin antibodies.
To investigate whether the unexpectedly high C-peptide levels in some insulin-dependent diabetic (IDDM) patients are due to co-determination of proinsulin bound to circulating insulin antibodies, 36 randomly selected sera from IDDM patients were assayed for C-peptide immunoreactivity (CPR) after polyethylene glycol (PEG) extraction, preceding incubation with proinsulin binding antibodies (LAB + PEG) or without pretreatment of the sera. Recovery of proinsulin was checked by addition of 1 nmol/l proinsulin to all sera. Recovery was found to be 101.5 +/- 4.0%. The mean values of concentrations were significantly lower (p less than 0.001) after treatment with PEG and IAB + PEG compared to the untreated sera. There was also a significant difference (p less than 0.05) between sera extracted with PEG alone or after IAB + PEG-treatment. However, no correlation (p greater than 0.1) was found to bound insulin (total minus free insulin) or to insulin binding capacity (IBC) of the sera. If an antiserum is not available with very low cross-reactivity with proinsulin to determine human C-peptide then sera should not be extracted with PEG alone but after additional incubation with a proinsulin binding antiserum. In spite of the extraction in some cases unexplicably high C-peptide levels may still be expected. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; In Vitro Techniques; Insulin; Polyethylene Glycols; Proinsulin; Radioimmunoassay | 1990 |
Autoantibodies against insulin (IAA), C-peptide (CAA), and glucagon (GAA) in new-onset type 1 diabetic patients.
Autoantibodies against insulin, C-peptide, and glucagon were determined by radio-binding assay in 63 new-onset Type 1 (insulin-dependent) diabetic patients as well as in 70 controls. Plasma peptide binding was determined by means of 125I-labeled peptides and charcoal-dextran separation technique. Binding values exceeding the mean plus three standard deviations of the controls were considered as antibody-positive. Sixteen patients (25%) were positive for IAA, as 6 (10%) were positive for CAA and 2 (3%) for GAA. Of all control subjects, none were positive for either IAA or CAA, whereas 2 (2%) had GAA. The mean 125I-glucagon binding in the patients' group was, however, slightly enhanced and could be suppressed to normal values by excess unlabeled glucagon. The presence of IAA and/or CAA was significantly associated with more severe symptoms at diabetes manifestation. These results indicate that in new-onset Type 1 diabetics autoimmunity arises against all the insular peptides tested but is predominantly directed against those antigens secreted from the beta cells. Nevertheless, extremely low-binding GAA seem to be common in these patients. The determination of IAA/CAA might be useful in detecting a possible heterogeneity of Type 1 diabetes with regard to its clinical mode of manifestation. Topics: Age Factors; Autoantibodies; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Islets of Langerhans; Male; Sex Factors | 1990 |
Persistence of serum antibodies to 64,000-Mr islet cell protein after onset of type I diabetes.
Antibodies to an islet protein of 64,000 Mr (64K antibodies) were measured in 15 diabetic children who were followed prospectively for up to 3 yr after onset of type I (insulin-dependent) diabetes. Of the 15 children, 12 were positive for 64K antibodies at diagnosis. Those patients who were negative for these antibodies at onset remained negative throughout the study. Modest increases in 64K antibodies were observed in 7 patients within 1 mo of diabetes onset, concomitant with an increase in C-peptide concentrations. All antibody-positive patients were still positive at the end of the study, with no significant decrease in antibody levels relative to those at diagnosis, whereas C-peptide concentrations decreased between 3 and 24 mo after onset. Islet cell antibodies, measured by immunochemical staining on sections of rat pancreas, were detected in 9 of 15 patients at onset, whereas only 3 of 11 patients were still positive after 3 yr. In an additional group of 11 patients with diabetes for 6-7 yr, when basal and stimulated C-peptide concentrations were undetectable, 4 patients were still positive for 64K antibodies. These results demonstrate that levels of 64K antibodies persist during the first 3 yr of diabetes, despite declining beta-cell function and decreased immune responses to other islet antigens, but decrease during the next 3-4 yr as the remaining functional beta-cells disappear. Topics: Adolescent; Antibodies; Autoradiography; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Osmolar Concentration; Precipitin Tests; Proteins | 1990 |
Pancreatic C-peptide response to oral glucose in fibrocalculous pancreatic diabetes. Improvement after treatment.
beta-Cell function (plasma C-peptide) in 17 fibrocalculous pancreatic diabetic (FCPD) subjects (14 newly diagnosed) was not different at presentation from that in 14 matched insulin-dependent diabetic subjects. After insulin treatment and improvement in the patients' nutritional and metabolic status, fasting and postglucose plasma C-peptide concentrations showed a significant increase (fasting 0.06 +/- 0.01 to 0.17 +/- 0.03 nM, peak 0.11 +/- 0.02 to 0.29 +/- 0.06 nM, mean +/- SE; P less than 0.01 for both). Thus, severely diminished beta-cell function in FCPD is partially reversible after treatment. This could contribute to the clinical metabolic peculiarities of this group of patients. Topics: Adult; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Fibrosis; Follow-Up Studies; Fructose; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Male; Pancreatic Diseases | 1990 |
Insulin as risk factor for vascular disease.
Topics: C-Peptide; Coronary Disease; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Humans; Insulin | 1990 |
[Nocturnal continuous subcutaneous insulin infusion--a therapeutic possibility in labile type I diabetes under exceptional conditions].
The whole-day continuous subcutaneous insulin infusion (CSII) with portable pumps in daily blood glucose autocontrol guarantees a more stabile and favourable glycaemia than multiple injections in labile type I diabetics. The success is mainly to be traced back to the continuous replacement of the basal secretion, particularly to the nocturnal fasting phase. In this study the effect on the glycaemia is investigated with exclusively nocturnal administration of the CSII under maintenance of multiple insulin injections during this day. In a group of 18 type I diabetics the nocturnal CSII in comparison to intermediate insulin administrations in the evening led to a significant improvement of glycaemia (p less than 0.01), in particular to the decrease of the fasting blood sugars (p less than 0.05). In two casuistic observations in comparison to all the other conventional methods for the compensation of the nocturnal glycaemia (depot insulin, nocturnal injection of normal insulin) the nocturnal CSII proved to be superior. Therefore, the nocturnal CSII is an--though more rarely to be used--alternative, which may be taken into consideration, of a whole-day CSII is temporarily unwished for. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Drug Administration Schedule; Female; Humans; Insulin; Insulin Infusion Systems; Male | 1990 |
Characterization of the late posthypoglycemic insulin resistance in insulin-dependent diabetes mellitus.
The insulin effect (6.5 to 7.5 hours) following hypoglycemia was studied with the euglycemic clamp technique in eight patients with insulin-dependent diabeteses mellitus (IDDM). The results were compared with a control study with the same insulin infusion, but where hypoglycemia was prevented by a glucose infusion. Glucose production (Ra) and utilization (Rd) were evaluated with D-(3-3H) glucose infusion. Hypoglycemia (glucose nadir, 1.5 +/- 0.1 mmol/L) caused a marked increase in cortisol and growth hormone, whereas the release of adrenaline and, in particular, glucagon was low. The plasma free insulin levels were similar in the studies, including during the clamp periods. The glucose infusion rates (GIR) were significantly lower after the hypoglycemia as compared with the control study (control, 2.4 +/- 0.3; hypoglycemia, 1.5 +/- 0.3 mg/kg x min; P less than .05). Thus, hypoglycemia induces prolonged insulin resistance. The posthypoglycemic insulin resistance during a moderate hyperinsulinemic (approximately 30 mU/L) clamp was mainly due to a decreased insulin effect on glucose utilization (control, 2.9 +/- 0.2; hypoglycemia, 2.2 +/- 0.2 mg/kg x min; P less than .02), whereas the insulin effect on glucose production was not significantly different after hypoglycemia. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Glucose; Glucose Clamp Technique; Glycated Hemoglobin; Growth Hormone; Humans; Hydrocortisone; Hypoglycemia; Insulin; Insulin Resistance; Male; Random Allocation | 1990 |
Direct relationship of antepartum glucose control and fetal erythropoietin in human type 1 (insulin-dependent) diabetic pregnancy.
In the present study the antepartum relationship between maternal diabetic glucose control and fetal hypoxaemia was examined in 44 Type 1 (insulin-dependent) diabetic and 23 non-diabetic control pregnancies. Maternal HbA1C was used to assess maternal integrated blood glucose control while fetal metabolic control was evaluated by antepartum glucose, insulin, and C-peptide determinations in amniotic fluid at elective caesarean delivery. Fetal hypoxaemia was assessed indirectly by fetal umbilical vein plasma erythropoietin level at delivery. A prospectively developed statistical pathway model was used to examine the relationship of these variables. In applying forced stepwise multiple regression with this model, we observed in the diabetic subjects that mean maternal HbA1C during the last month of pregnancy correlated significantly with fetal umbilical venous erythropoietin at delivery (r = 0.57, p less than 0.001). Additional significant contributions to umbilical venous erythropoietin were found for amniotic fluid glucose and amniotic fluid insulin when these two independent variables were added in stepwise fashion (p less than 0.01). We conclude that in diabetic pregnancy, antepartum control of maternal hyperglycaemia is a significant factor associated with fetal hypoxaemia. We speculate that this effect is mediated through perturbations which accelerate fetal metabolism and which is expressed by amniotic fluid levels of glucose and insulin. Topics: Amniotic Fluid; Biomarkers; Birth Weight; Blood Glucose; C-Peptide; Cesarean Section; Diabetes Mellitus, Type 1; Erythropoietin; Female; Fetal Blood; Glucose; Glycated Hemoglobin; Humans; Infant, Newborn; Insulin; Models, Biological; Pregnancy; Pregnancy in Diabetics; Prospective Studies; Reference Values; Regression Analysis; Umbilical Veins | 1990 |
Standard breakfast test: an alternative to glucagon testing for C-peptide reserve?
We measured C-peptide after glucagon and breakfast tests to compare the effectiveness of both tests in evaluating residual beta cell function in normal and diabetic subjects. A significantly higher C-peptide response was elicited after standard breakfast in patients with insulin-dependent diabetes mellitus of less than two years' evolution, ranging from 0.12 +/- 0.07 to 0.83 +/- 0.18 ng/ml (P less than 0.05). In nonobese noninsulin-dependent diabetes mellitus the response ranged from 0.86 +/- 0.02 to 1.89 +/- 0.48 ng/ml (P less than 0.0025); in obese NIDDM from 1.02 +/- 0.37 to 1.55 +/- 0.46 ng/ml (P less than 0.05), and in normal subjects from 0.77 +/- 0.23 to 2.11 +/- 1.22 ng/ml (P less than 0.0025). We conclude that the standard breakfast test is a useful and practical approach to the study of residual beta cell function. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Food, Formulated; Glucagon; Humans; Islets of Langerhans; Middle Aged | 1990 |
The effects of improved blood glucose on growth hormone and cortisol secretion in insulin-dependent diabetes mellitus.
Growth hormone and cortisol secretion were studied in 25 patients with insulin-dependent diabetes before (Study 1) and 2 weeks after improved glucoregulation (Study 2). Blood samples for serum growth hormone (GH) and blood glucose determination were collected at hourly intervals whilst blood samples for cortisol and C-peptide were collected every 6 h during the 24-h period in Study 1 and Study 2. Glycaemic control was significantly improved in Study 2 compared to that in Study 1 (8.5 vs 13.3 mmol/l; P less than 0.001). With improved control, growth hormone levels rose by 21% (5.7 vs 4.7 mU/l; P less than 0.05). Throughout both study periods growth hormone levels were higher in patients with no residual C-peptide secretion (10 CpN patients) compared with patients with residual beta-cell function (15 CpP patients) (7.1 vs 3.2 mU/l in Study 1; 8.9 vs 4.2 mU/l in Study 2; P less than 0.001). Characteristic shapes of the 24-h blood glucose profile curves during both study periods were significantly different between the CpN and CpP group. Plasma cortisol decreased in both groups with improved metabolic control (P less than 0.001) but the observed different diurnal pattern did not change. These results demonstrate the importance of residual endogenous insulin secretion in determining growth hormone secretion in insulin-dependent diabetes and have important implications for glycaemic control and risk of microvascular complications. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Growth Hormone; Humans; Hydrocortisone; Insulin; Male; Middle Aged | 1990 |
Relationships among islet cell antibodies, residual beta-cell function, and metabolic control in patients with insulin-dependent diabetes mellitus of long duration: use of a sensitive C-peptide radioimmunoassay.
Relationships among islet cell antibodies (ICA), residual beta-cell function, and metabolic control were studied in 60 insulin-dependent diabetics (IDDs) of long duration (6 to 31 years). Sensitive C-peptide immunoreactivity (CPR) and ICA assays with limits of 0.017 nmol/L and 5 Juvenile Diabetes Foundation (JDF) U, respectively, demonstrated that baseline (0.16 +/- 0.02 nmol/L, mean +/- SE, n = 26), as well as maximum CPR values (0.34 +/- 0.05 nmol/L), during 100-g oral glucose tolerance tests (OGTT) in ICA-positive IDDs were significantly higher than corresponding values in ICA-negative ones (baseline values, 0.10 +/- 0.01 nmol/L, P less than .05; maximum values, 0.20 +/- 0.04 nmol/L, P less than .01, n = 34). Negative correlation was observed between increment of serum CPR and metabolic control indices, including fasting blood glucose (FBG) and HbA1c levels (P less than .05). In addition, ICA-positive insulin-dependent diabetes mellitus (IDDM) patients had lower values of FBG (8.2 +/- 0.4 mmol/L, P less than .01 v ICA-negative IDDs) and HbA1c (9.2% +/- 0.2%, P less than .05 v ICA-negative IDDs) than ICA-negative ones (FBG, 9.9 +/- 0.4 mmol/L; HbA1c, 9.8% +/- 0.2%). These results indicate that minute CPR responses to OGTT detected by sensitive methods may represent residual pancreatic beta cells, which may contribute to ICA generation and good metabolic control in IDDs of long duration. Topics: Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Islets of Langerhans; Male; Middle Aged; Radioimmunoassay; Time Factors | 1990 |
Effect of isocaloric substitution of chocolate cake for potato in type I diabetic patients.
Traditional dietary advice given to people with diabetes includes eliminating simple sugars (primarily sucrose) from the diet. Many people have difficulty following this recommendation. Because patients with type I (insulin-dependent) diabetes do not need overall calorie restriction, there is no caloric reason to restrict sucrose. In this study, we looked at the effect of the isocaloric substitution of a piece of chocolate cake for a baked potato in a mixed meal to determine whether this would increase the blood glucose in patients with type I diabetes. The glucose response to a cake-added meal was significantly greater than to a standard meal. The glucose response was no different between a cake-substitution meal and a standard meal. The reproducibility studies showed no difference between repeated standard meals. The urinary glucose excretion was significantly greater after a cake-added meal but was no different with the other pairs. There were no significant differences in the counterregulatory hormone responses at baseline between any of the paired studies. In conclusion, patients with type I diabetes may substitute a sucrose-containing dessert for another carbohydrate in their diet without compromising their postprandial glucose response. These data suggest that a dessert exchange may be helpful and not harmful in the management of diabetic patients. There is an inherent variability (at least 16%) in an insulin-requiring patient's response to a meal, making self-monitoring of blood glucose and adjustment of insulin doses necessary to achieve near euglycemia. Topics: Adult; Blood Glucose; C-Peptide; Cacao; Carbohydrate Metabolism; Diabetes Mellitus, Type 1; Diet, Diabetic; Female; Glycosuria; Humans; Male; Solanum tuberosum; Sucrose | 1990 |
Physiological and pharmacological stimulation of pancreatic islet hormone secretion in type I diabetic pancreas allograft recipients.
Successful heterotopic and denervated pancreas allograft transplantation (PAT) often results in normoglycemia and peripheral hyperinsulinemia in insulin-dependent (type I) diabetic recipients. The contribution of altered hepatic insulin extraction (HIE) to the resulting hyperinsulinemia in such patients remains uncertain. Furthermore, whether the denervated pancreas allografts exhibit beta-cell hyperresponsiveness to physiological and pharmacological stimulation is controversial. We evaluated beta-cell function and HIE after successful whole cadaveric PAT with systemic venous drainage in 13 type I diabetic patients before and after mixed-meal and intravenous glucose and glucagon administration. The results were compared with those of 5 nondiabetic patients with kidney transplantation only, who had native innervated pancreases with portal insulin delivery and were receiving an equivalent triple immunosuppressive therapy (cyclosporin, azathioprine, and prednisone), and 7 healthy control subjects with no family history of diabetes. After PAT, fasting and poststimulation serum glucose concentrations were normalized. PAT was associated with marked basal hyperinsulinemia (3- to 8-fold) as assessed by immunoreactive insulin (IRI) levels in type I diabetic patients (mean +/- SE 345 +/- 43 pM) compared with control subjects (43 +/- 14 pM) and nondiabetic kidney-transplantation patients (129 +/- 38 pM). After mixed-meal ingestion, the mean incremental integrated insulin area was similar in PAT patients (18 +/- 3 nM.min) compared with kidney-transplantation patients (20 +/- 4 nM.min) and healthy control subjects (21 +/- 3 nM.min). Basal serum C-peptide levels were significantly greater in PAT (1.72 +/- 0.13 nM) and kidney-transplantation (2.15 +/- 0.33 nM) patients than in healthy control subjects (0.50 +/- 0.10 nM; P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Kidney Transplantation; Male; Middle Aged; Pancreas Transplantation; Reference Values; Transplantation, Homologous | 1990 |
Limited duration of remission of insulin dependency in children with recent overt type I diabetes treated with low-dose cyclosporin.
Preliminary data from our group indicated that cyclosporin A induced frequent remissions of insulin dependency in a group of 40 insulin-dependent (type I) diabetic children if given at the onset of clinical manifestations of diabetes. We report a 2-yr analysis of the response to cyclosporin A in the group of 81 patients included in the initial study. As observed before, a remission could be obtained in most of the patients (65%) in association with a shorter duration of symptoms, less severe hyperglycemia, lower incidence of ketoacidosis, and higher plasma C-peptide concentrations. All remissions ended during the follow-up period after a mean +/- SE duration of 316 +/- 21 days (range 31-850 days). Two parameters were linked to the duration of remissions: the mean circulating level of cyclosporin during the first 3 mo and the duration of prediagnostic polyuria. We were unable to relate the end of a remission to variations in the cyclosporin regimen, titer of autoantibodies, or progression of beta-cell failure. The euglycemic clamp technique revealed that insulin sensitivity decreases with time in patients not taking insulin. At 24 mo, the patients who had a remission of insulin dependency had better glycemic control, lower insulin dosages, and C-peptide levels two- to threefold higher than the nonremission patients and four- to sixfold higher than the historical control subjects. The cyclosporin regimen was well tolerated over the observed period: more specifically, serum creatinine remained unchanged, and kidney biopsies performed at 18-24 mo of treatment were within normal limits.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Autoantibodies; C-Peptide; Child; Cyclosporins; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Glucose Clamp Technique; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1990 |
Vitreous fluorophotometry in juvenile diabetics with and without retinopathy in relation to metabolic control: insulin antibodies and c-peptide levels.
Vitreous fluorophotometry was performed in 56 juvenile insulin-dependent diabetic patients aged 9-23 years (median: 16 years), diabetes duration 1-20 years (median: 8 years). Fundus photography showed mild background retinopathy in 5 patients, while 51 patients had no signs of retinopathy. Abnormal leakage into the posterior vitreous body was found in 4/5 patients with background retinopathy and in 24/51 with normal fundi. We found a significantly positive correlation between abnormal leakage and duration of diabetes and HbA1 with Kendall rank-order correlation coefficients T = 0.21 (P = 0.01) and 0.19 (P = 0.02) resp. No significant correlation was found between leakage and age, actual blood glucose level or insulin antibodies expressed as insulin binding capacity of IgG, but a significantly negative correlation between abnormal leakage and low levels of fasting c-peptide/s T = 0.437 P less than 0.001. Kendall partial rank-order correlation analysis showed that c-peptide/s significantly explained the leakage when HbA1 or duration was kept constant. Duration could only explain leakage when HbA1 was fixed but not when c-peptide/s was kept constant. HbA1 could also explain leakage when duration or c-peptide was fixed. Topics: Adolescent; Adult; Blood-Retinal Barrier; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Fluorescein; Fluoresceins; Fluorophotometry; Hemoglobin A; Humans; Immunoglobulin G; Insulin Antibodies; Vitreous Body | 1990 |
Lymphocyte transfusion in recent onset type I diabetes mellitus--a one-year follow-up of cell-mediated anti-islet cytotoxicity and C-peptide secretion.
In 19 patients with newly diagnosed Type I diabetes mellitus a single transfusion of 1.9 x 10(9) to 1.5 x 10(10) lymphocytes was performed. Fifteen Type I diabetic patients who did not receive a transfusion were used as controls. Anti-beta-cell cell-mediated cytotoxicity was measured using an insulin release assay. Stimulated C-peptide secretion (100 g glucose orally, 1 mg glucagon i.v.) was used to estimate residual beta-cell function. Both parameters were measured prior to transfusion and after 12 months. The transfusions were followed by a fall of cytotoxicity below the 95% confidence limit of the controls in 11 of the 19 patients ('responders') (15.7 +/- 1.7 ng insulin/islet/20 h vs 6.7 +/- 1.3 P less than 0.001), while the other eight transfused patients ('non-responders') (13.5 +/- 1.9 vs 17.1 +/- 2.9, ns) and the non-transfused control patients (11.6 +/- 1.1 vs 14.2 +/- 2.4, ns) displayed persistently high cytotoxicity levels. In the responder group a slight improvement in stimulated C-peptide secretion was observed (136 +/- 43 pmol/dl vs 148 +/- 38, ns) whereas in the non-responder (127 +/- 28 vs 106 +/- 25, ns) and in the control group (130 +/- 17 vs 97 +/- 19, P less than 0.05) the stimulated C-peptide responses declined during the 12-month follow-up. Thus, lymphocyte transfusion may have beneficial effects by suppressing anti-beta-cell cytotoxicity and preserving C-peptide secretion. Topics: Adolescent; Adult; Autoimmune Diseases; Blood Transfusion; C-Peptide; Child; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Histocompatibility Testing; Humans; Insulin; Islets of Langerhans; Lymphocyte Transfusion; Lymphocytes; Male | 1990 |
[Clinical course of recent insulin-dependent diabetes mellitus and possibilities of controlling it therapeutically].
Intensive insulin treatment in a recent stage of IDDM promotes metabolic compensation of the disease regardless which regime of conventional or unconventional treatment is used. In thus treated patients more frequently complete or partial metabolic remission is achieved. C-peptide in patients in remission is much higher than in other patients, and conversely there are fewer persons without residual B-cell secretion. The manifestation of diabetes has an impact also on the clinical course of the disease. Normoglycaemia with possible metabolic remission associated with easy insulin administration a flexible lifestyle have a favourable effect on the onset of the life-long disease and eliminate to a minimum factors which have a negative psychosomatic impact on the patient. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male | 1990 |
The use of SMS 201-995, a somatostatin analog, in pancreas transplantation.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Humans; Kidney Failure, Chronic; Kidney Transplantation; Octreotide; Pancreas Transplantation | 1990 |
Glucagon-stimulated serum C-peptide levels in the early period following pancreas transplantation.
Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Glucagon; Graft Rejection; Humans; Kidney Transplantation; Male; Pancreas Transplantation | 1990 |
Metabolic control in recipients of duct-occluded segmental pancreatic grafts: a four-year follow-up.
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Follow-Up Studies; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Graft Survival; Humans; Immunosuppression Therapy; Kidney Transplantation; Pancreas Transplantation; Pancreatic Ducts; Postoperative Complications | 1990 |
The relevance of persistent C-peptide secretion in type 1 (insulin-dependent) diabetes mellitus to glycaemic control and diabetic complications.
The effect of residual C-peptide secretion in longer standing IDDM on glycaemic control and the prevalence and evolution of complications over 2 years was evaluated. Thirty-one subjects with IDDM of 15.4 (1.5) years duration (mean SEM)) and residual C-peptide secretion, were matched for age, duration of diabetes and body mass index with 31 subjects without detectable C-peptide secretion. At trial entry and over 2 years, levels of HbA1, fructosamine and mean blood glucose were essentially similar in both groups. Levels of glycated albumin (GSA) were significantly higher in the C-peptide negative group after 3 and 9 months (P less than 0.05). An increased prevalence of proliferative retinopathy in the C-peptide negative group and of peripheral vascular disease in the C-peptide secretor group was apparent at entry to the study (both P less than 0.05), although no significant differences were observed after 1 or 2 years. There was no difference in the prevalence of peripheral or autonomic neuropathy, hypertension, nephropathy or ischaemic heart disease. Subjects with C-peptide concentrations greater than 0.100 pmol/ml at entry to this study had lower daily insulin requirements after 1 and 2 years, but behaved like the larger group with any detectable C-peptide secretion in all other respects. Residual C-peptide secretion was lost after 1 year in 7 patients, in whom glycaemic control during the year had been particularly poor. Insulin antibody titres were no different in the 2 groups at any time point. This study suggests that residual C-peptide secretion in longer standing IDDM confers the potential for limited improvements in glycaemic control. This effect appears to be insufficient to prevent the evolution of microvascular complications over a 2-year period. Residual C-peptide secretion and relative hyperinsulinaemia may be associated with an excess of peripheral vascular disease. Topics: Adult; Albuminuria; Biomarkers; Blood Glucose; Blood Glucose Self-Monitoring; Blood Pressure; C-Peptide; Coronary Disease; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Follow-Up Studies; Fructosamine; Glycated Hemoglobin; Hexosamines; Humans; Hypertension; Middle Aged | 1990 |
Metabolic studies of type I diabetics after successful segmental pancreas and kidney transplantation.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Glucagon; Growth Hormone; Humans; Kidney Transplantation; Norepinephrine; Pancreas Transplantation; Reference Values | 1990 |
Appearance of type II diabetes mellitus in type I diabetic recipients of pancreas allografts.
To determine the cause of hyperglycemia appearing after pancreas transplantation in type I diabetic recipients, we performed 65 oral glucose tolerance tests with serum insulin and C-peptide determinations in 32 patients with pancreas grafts functioning two or more months following transplantation. We correlated these results with estimates of graft size obtained by magnetic resonance imaging (MRI) and values of urinary amylase as a measure of pancreatic exocrine function. A total of 33 studies were obtained in 20 patients at times of normal glucose tolerance, and normal ranges for serum insulin and C-peptide levels were established; 32 studies in 17 patients during periods of glucose intolerance revealed values of serum insulin and C-peptide that were within the normal range, though the time to peak values was delayed to 2 hr, characteristic of type II diabetes. Only 3 of 17 patients examined by MRI had significant pancreatic allograft atrophy. These patients also had low urinary amylase excretion, and the only values for serum C-peptide that were below the normal range. The other 14 hyperglycemic patients had normalized pancreas grafts, normal urinary amylase excretion, and normal values for serum insulin and C-peptide. In our experience, then, in 76% of patients with hyperglycemia more than 2 months following pancreas transplantation, the cause was appearance of type II diabetes rather than destruction of the allograft with recurrence of type I diabetes. This observation has important implications for the definition of pancreas allograft failure and for the management of pancreas allograft recipients with hyperglycemia. Topics: Amylases; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Humans; Insulin; Magnetic Resonance Imaging; Pancreas Transplantation; Postoperative Complications; Recurrence; Reference Values | 1989 |
Appearance of type II diabetes mellitus in type I diabetic recipients of pancreas allografts.
Topics: Amylases; Atrophy; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Insulin; Pancreas; Pancreas Transplantation; Postoperative Complications | 1989 |
[Determination of insulin in saliva and its correlation with plasma insulin. Assessment of the possible participation++ of the salivary glands in the production of the hormone].
The finding of immunoreactive insulin (IRI) in saliva and an insulin-like protein, similar to pancreatic insulin and with the same biological activities, suggest that both products are pancreatic insulin stored and/or eliminated in the salival manner or an extrapancreatic hormone synthesis, bearing in mind the features which both glands share. The aim of this study is to ascertain whether the amount of insulin from saliva depends on plasmatic insulin and, if so, whether this is a form of elimination. Our results pointed out that the amount of insulin in saliva is similar to the plasmatic insulin in those patients with normal pancreatic function. The oral glucose tolerance test was carried out on 20 patients. The maximum insulin level was produced at the same time as maximum serum glucose level, taking place 60 minutes later. These data, support the concept that salival insulin is a product of the elimination more than synthesis by salival glands, however we can not exclude the possibility of synthesis by the salival gland without direct studies, the ideal test being the immunocytochemist. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Tolerance Test; Humans; Insulin; Male; Middle Aged; Saliva; Salivary Glands | 1989 |
Transplantation of proliferated human pre-islet cells into diabetic patients with renal transplants.
Topics: Adult; Animals; C-Peptide; Cell Transformation, Neoplastic; Diabetes Mellitus, Type 1; Female; Graft Rejection; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney Transplantation; Magnetic Resonance Imaging; Male; Mice; Mice, Nude; Middle Aged; Quality Control; Stem Cell Transplantation; Stem Cells; Tomography, X-Ray Computed | 1989 |
[Clinical and biological data affecting insulin-dependent diabetes in French children at the time of its diagnosis].
In order to characterize Type I diabetes at its clinical onset in French children, we studied HLA-DR alleles, beta-cell function and autoantibodies to islet-cell antigens and insulin in 115 patients aged 1.8-17 years. Beta-cell function was markedly impaired, but with an unexpectedly wide range of individual variations. These variations showed no correlation with HLA alleles or circulating autoantibodies, as opposed to observations made by others. Age, however, had a clear influence on the degree of impairment of residual insulin secretion, the younger children having the more deteriorated beta-cell secretory capacity conditioning the severity of clinical manifestations (weight loss, ketonuria, ketoacidosis) and initial hyperglycemia. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; France; HLA-DR Antigens; Humans; Infant; Insulin Antibodies; Male; Polyuria; Weight Loss | 1989 |
The influences of islet transplantation on metabolic abnormalities and diabetic complications.
To assess the long-term effect of islet transplantation on metabolic abnormalities and chronic complications of diabetic recipients, the long-term follow-up data of 36 type 1 diabetic subjects with functioning islet grafts for more than 1 year were analysed in this article. 36 type 1 diabetics, with mean age of 34.30 +/- 12.05 yr and mean duration of 11.53 +/- 5.29 yr, were followed up for a mean period of 29.39 +/- 9.50 mo after successfully transplanting with short-term cultured islet tissue of human fetal pancreases. The effect of islet transplants was identified as excellent in 13 subjects, good in 12 and fair in 11. The comparative studies were carried out of the mean levels of serum C-peptide, plasma glucose, GHb and GPP, serum lipids, and mean excretion of urine sugar, and the diabetic retinopathy, nephropathy as well as the autonomic neuropathy before transplantation in comparison with those of the present. The results of the study demonstrated that islet transplants could improve the function of islet B cells and the glucose metabolism, and might delay the development of diabetic retinopathy, nephropathy and autonomic neuropathy in successfully transplanted diabetic recipients, but not exert any influences on those of patients in fair group. Topics: Adolescent; Adult; C-Peptide; Carbohydrate Metabolism; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Follow-Up Studies; Humans; Islets of Langerhans Transplantation; Lipids; Male; Middle Aged | 1989 |
Islet cell transplantation in type I diabetes mellitus: evaluation of humoral immune response.
Four males and three females ranging in age from 20 to 35 years and afflicted with complicated Type 1-diabetes for more than 8 years underwent islet cell allotransplantation (ATx, 6 cases) and xenotransplantation (XTx, 1 case). Precultured islet cells derived from human or bovine fetal pancreata were injected into the m. rectus abdominis. Immunosuppression was not applied. Plasma C-peptide and islet cell surface antibodies (ICSA) were continually measured both before and until the twentienth week following islet cell transplantation. All recipients were subdivided as "responsive" (RR, 3 males) or "non-responsive" (NRR, 1 male and 3 females), according to the dynamics of their ICSA levels. All 3 RR (1XTx and 2 ATx) showed a peak of ICSA two weeks after cell injection. Subsequent ICSA levels had the tendency to either diminish or increase. Heterogeneity of preoperative antibody level, especially in NRR, was also observed. No associations between ICSA and ATx or XTx, age at diabetes onset, or duration of the disease was found. Only one RR with XTx had a reduced daily insulin requirement and a significant C-peptide response similar to the dynamics of ICSA levels. A greater mass of available bovine islet cells might be responsible for this effect. Topics: Adult; Animals; Antibody Formation; Antigens, Surface; Autoantibodies; C-Peptide; Cattle; Cells, Cultured; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Transplantation, Homologous | 1989 |
Adrenal androgens in insulin-dependent diabetes mellitus.
The adrenal androgens dehydroepiandrosterone sulphate (DHAS) and androstenedione (A2) are major secretory products of the adrenal gland, although their precise function is unclear. There is limited evidence to suggest adrenal androgen levels may be altered in diabetes, and that insulin secretion may influence these hormones. Therefore we have measured fasting levels of serum DHAS, A2, testosterone, oestradiol (in males only), sex hormone binding globulin (SHBG), HbA1 and C-peptide (basal and glucose stimulated), in 17 post-pubertal, uncomplicated patients with insulin-dependent diabetes mellitus (IDDM), and made comparisons to 17 of their sex and age-matched (to within 5 yr) non-diabetic siblings. Concentrations of the adrenal androgens were within the laboratory normal range in all the subjects and no differences were noted between the diabetics and their siblings or between males and females. No correlations were noted between the hormones and either HbA1 or C-peptide. In contrast to previous reports we have found that C-peptide status does not influence adrenal androgen levels, and that normal concentrations of these androgens are found in non-ketotic patients with IDDM. Topics: Adrenal Cortex Hormones; Adult; Androstenedione; C-Peptide; Dehydroepiandrosterone; Dehydroepiandrosterone Sulfate; Diabetes Mellitus, Type 1; Estradiol; Female; Glycated Hemoglobin; Humans; Male; Reference Values; Sex Hormone-Binding Globulin; Testosterone | 1989 |
Insulin regulation of lipolysis in nondiabetic and IDDM subjects.
To determine whether insulin regulation of lipolysis is abnormal in subjects with poorly controlled insulin-dependent diabetes mellitus (IDDM), free-fatty acid flux ([1-14C]palmitate) was measured under conditions ranging from complete insulin withdrawal to hyperinsulinemia. Seven nondiabetic and seven IDDM subjects were studied with the pancreatic clamp technique to control plasma insulin, growth hormone, and glucagon concentrations at the desired levels. Preliminary studies were performed to validate the experimental design. The palmitate flux response to insulin withdrawal (2.5 +/- 0.2 vs. 2.5 +/- 0.2 mumol.kg-1.min-1) and maximally antilipolytic insulin concentrations (0.17 +/- 0.02 vs. 0.23 +/- 0.03 mumol.kg-1.min-1) were not different in nondiabetic and IDDM subjects, respectively. In contrast, IDDM subjects required significantly greater plasma free-insulin concentrations to result in equivalent suppression of palmitate flux compared with nondiabetic subjects. Lipolysis was found to be very sensitive to insulin in nondiabetic humans, with half-maximal suppression occurring at plasma free-insulin concentrations of approximately 12 pM (less than 2 microU/ml). We conclude that adipose tissue lipolysis is normally exquisitely sensitive to insulin and that sensitivity, but not responsiveness to insulin, is impaired in poorly controlled IDDM. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Growth Hormone; Humans; Hydrocortisone; Insulin; Kinetics; Lipolysis; Male; Palmitic Acid; Palmitic Acids; Reference Values; Somatostatin | 1989 |
Retinopathy in insulin dependent diabetes mellitus (IDDM) in south India.
The prevalence of diabetic retinopathy was assessed by direct and indirect ophthalmoscopy in a group of patients with insulin dependent diabetes mellitus (IDDM). Fourteen percent of patients had retinopathy. Proliferative retinopathy and severe background retinopathy including maculopathy were both seen in four percent of patients. It is possible that the lower prevalence rates for these complications is due to the shorter duration of diabetes in our patients. Topics: Adult; Blood Glucose; C-Peptide; Developing Countries; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; India; Male | 1989 |
[New diagnostic tests for diabetes mellitus. C-peptide and proinsulin].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Hyperinsulinism; Pancreatic Function Tests; Proinsulin; Reference Values | 1989 |
Islet-cell antibodies: markers of a more severe insulin-dependent diabetes mellitus?
The aim of the present study was to analyze if an association exists between metabolic condition, C-peptide secretion and islet-cell antibody (ICA) presence in insulin-dependent diabetes mellitus (IDDM) at the clinical onset of the disease. Two hundred and nine IDDM patients were studied at diagnosis. 89% of the subjects showed residual C-peptide secretion that correlated inversely with blood glucose and glycosylated hemoglobin at diagnosis and with insulin requirement at discharge. Islet-cell antibodies were detected in 68.6% of the patients, complement-fixing ICA in 30% and insulin autoantibodies in 17.3%. Islet-cell antibody positive patients had a lower glucagon stimulated C-peptide than ICA negative subjects (0.41 +/- 0.22 versus 0.54 +/- 0.25 nmol/l, p = 0.005). However patients with high titers of ICA expressed in JDF units (JDF greater than 20) showed similar C-peptide secretion than ICA positive patients with a low level of JDF (JDF less than 20). When acid-base condition was analyzed patients on ketoacidosis at diagnosis had significant higher insulin requirement, lower C-peptide secretion and higher prevalence of ICA compared to patients that were not ketotic at diagnosis. Our findings suggest that residual beta-cell secretion plays a role on metabolic condition at diagnosis of IDDM and that ICA may be the markers of a more severe form of IDDM. Topics: Adolescent; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Male; Prognosis | 1989 |
Fate of late complications in type I diabetic patients after successful pancreas-kidney transplantation.
The success rate of pancreas transplantation allows us to study in more detail the potential beneficial effects of normoglycemia on secondary complications in diabetes mellitus. We report a prospective follow-up (mean 26 mo) of metabolic control, neuropathy, retinopathy, and peripheral microcirculation in 31 patients with type I (insulin-dependent) diabetes (mean age 33 +/- 1 yr; mean duration of diabetes 21 +/- 1 yr) after combined kidney and segmental pancreas grafting. All patients had normal HbA1 levels. Glucose tolerance (GT), insulin, C-peptide, and glucagon were normal in 22 patients, and impaired oral GT with reduced insulin secretory capacity was seen in 9 patients. During follow-up, there was no deterioration of GT and insulin release. Vascular risk factors, e.g., hypertension, cholesterol, and triglycerides, decreased after grafting. Autonomic neuropathy improved clinically, and R-R variation increased significantly in 3 of 18 patients. Peripheral neuropathy improved clinically in 46% of patients and did not deteriorate in the others. Motor nerve conduction velocity increased greater than 20% in 8, less than 20% in 12, and was unchanged in 8 of 28 recipients. Most of the patients (n = 30) had pretransplant laser treatment of their advanced retinopathy. Posttransplant visual acuity improved at least more than one line in 56%, stabilized in 32%, and deteriorated in 12% of patients. Patients with functioning grafts for greater than 1 yr had no further deterioration of visual acuity. Vitreous hemorrhage frequency and severity dropped markedly from pretransplant (from 69 to 24%) 10 mo after grafting. Retinal morphology remained stable in all eyes except two.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Diabetic Retinopathy; Female; Glucagon; Humans; Insulin; Kidney Transplantation; Male; Microcirculation; Pancreas Transplantation; Prospective Studies | 1989 |
Maturity-onset diabetes of the young. Studies in a Norwegian family.
A Norwegian family showed 20 cases of verified or suspected diabetes in 5 generations, 13 being females and 7 males. In 12 patients the diagnosis was established at 26 years of age or earlier. Fourteen patients were definitely non-insulin-dependent. A high frequency of severe diabetic ophthalmopathy was noted, five patients were blind, two had proliferative retinopathy, and one simplex retinopathy and cataract. Five patients from the last 3 generations were islet cell antibody negative and C-peptide positive. In selected patients the serum insulin response to oral glucose was markedly reduced. HLA determinations in these patients showed absence of DR3 and DR4, and presence of DR2. The inheritance of diabetes in this family is compatible with an autosomal, dominant trait, and the majority of cases fulfilled the criteria of maturity-onset diabetes of the young. The high frequency of severe ophthalmopathy underscores that this disease may have an unfavourable evolution. Topics: Adolescent; Adult; Age Factors; Aged; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Glucose Tolerance Test; Humans; Insulin; Male; Middle Aged; Norway; Pedigree | 1989 |
A comparison of childhood and adult type I diabetes mellitus.
The incidence rate of insulin-dependent (Type I) diabetes mellitus is bimodal: one peak occurs close to puberty, and the other in the fifth decade. To evaluate possible differences in these forms of the disease, we examined the clinical, biochemical, autoimmune, and genetic features of 82 children and adolescents (1.3 to 18.2 years old) and 44 adults (20.0 to 55.8 years old) when they presented with Type I diabetes. The mean (+/- SEM) duration of symptoms before diagnosis was longer in the adults (7.5 +/- 1.0 vs. 3.9 +/- 0.4 weeks; P less than 0.001), and their serum C-peptide concentrations at diagnosis were higher (0.29 +/- 0.03 vs. 0.17 +/- 0.01 nmol per liter; P less than 0.001), suggesting that they had more residual beta-cell function. There were no significant differences between the two groups in sex ratio, blood glucose levels, hemoglobin A1 values, degree of metabolic decompensation, or frequency of Type I diabetes in first-degree relatives. Thirty-four of 80 children tested (42.5 percent) were positive for insulin autoantibodies, as compared with only 1 of 26 adults (3.8 percent; P less than 0.001). However, the frequencies of islet-cell autoantibodies were similar in the adults and children (conventional autoantibodies, both 81 percent; complement-fixing autoantibodies, 46.2 percent and 60 percent). More children than adults were heterozygous for both HLA-Dw3/4 antigens (26.6 percent vs. 9.8 percent; P less than 0.05) and HLA-DR3/4 antigens (36.6 percent vs. 12.5 percent; P less than 0.05). We conclude that Type I diabetes that begins in adulthood is characterized by a longer symptomatic period before diagnosis, better preservation of residual beta-cell function, and lower frequencies of insulin autoantibodies and HLA-D3/D4 heterozygosity than Type I diabetes that begins in childhood or adolescence. Topics: Adolescent; Adult; Age Factors; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Heterozygote; HLA-DR Antigens; Humans; Infant; Insulin Antibodies; Islets of Langerhans; Male; Middle Aged; Pancreas | 1989 |
Clinical significance of urinary C-peptide excretion in children with insulin-dependent diabetes mellitus.
In order to evaluate the accuracy of urinary C-peptide determination and the clinical significance of C-peptiduria for the early course of insulin-dependent diabetes (IDDM), the rate of urinary excretion of C-peptide was determined in 32 children and adolescents with IDDM and correlated with serum C-peptide concentration, urinary excretion of albumin and beta 2-microgloublin and with the glomerular filtration rate (GFR) measured in terms of the clearance of 99mTc-DTPA. The age of the subjects ranged from 9.1 to 17.1 years (mean 13.1) and the duration of diabetes from 0.3 to 11.9 years (mean 4.6). There was a good correlation between postprandial serum C-peptide concentration and the 24-hour urinary C-peptide excretion rate (r = 0.81; p less than 0.001). GFR and urinary albumin excretion were slightly elevated in the diabetic patients as compared with non-diabetic subjects (p less than 0.05 and p less than 0.001, respectively), but C-peptide excretion was unrelated to the degree of hyperfiltration or albuminuria, neither was there any correlation between the excretion rate of beta 2-microglobulin and C-peptide. Glycaemic control was poorer in the diabetic children who had only trace amounts of C-peptide in their urine (less than 0.05 nmol/m2/24 h) than in those with minimal (0.05-1.0 nmol/m2) or moderate 24-hour urinary C-peptide excretion (greater than 1.0 nmol/m2). It is concluded that urinary C-peptide excretion serves very well to reflect residual beta-cell function and is unrelated to the slight renal hyperfunction and albuminuria often seen in diabetic subjects.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Age Factors; Albuminuria; beta 2-Microglobulin; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glomerular Filtration Rate; Humans; Male; Reference Values; Sex Factors; Time Factors | 1989 |
Factors associated with fasting and postglucagon plasma C-peptide levels in middle-aged insulin-treated diabetic patients.
We studied fasting and postglucagon plasma C-peptide levels and factors associated with them in two representative studies of middle-aged insulin-treated diabetic patients whose diabetes had been diagnosed after the age of 30 yr. Altogether, 75 men and 79 women from East Finland and 83 men and 62 women from West Finland aged 45-64 yr were studied. Of these patients, 44.4% had undetectable fasting and 38.5% undetectable postglucagon C-peptide concentrations. The phi-coefficient expressing the concordance of fasting and postglucagon C-peptide concentrations in the classification of diabetic patients into nonresponders and responders was .75 in men and .91 in women. In multiple stepwise regression analyses, body mass index (BMI) and the period between diabetes diagnosis and the initiation of insulin treatment were positively and duration of diabetes inversely associated with fasting and postglucagon C-peptide levels in both sexes. We concluded that 1) insulin deficiency is not uncommon in middle-aged insulin-treated diabetic patients whose diabetes has been diagnosed after the age of 30 yr; 2) fasting C-peptide levels contain basically the same information as postglucagon C-peptide levels; and 3) a low BMI, a need for insulin treatment soon after the diagnosis of diabetes, and a long duration of diabetes are predictive of insulin deficiency. Topics: C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Finland; Glucagon; Glycated Hemoglobin; Humans; Insulin; Male; Middle Aged; Sex Factors | 1989 |
Is there a future for fetal pancreas transplantation?
Topics: Animals; C-Peptide; Diabetes Mellitus, Type 1; Fetus; Humans; Mice; Mice, Nude; Pancreas; Pancreas Transplantation; Tissue Donors; Transplantation, Heterologous; Transplantation, Homologous | 1989 |
Maleness as risk factor for slowly progressive IDDM.
The effect of sex on longitudinal changes in serum C-peptide immunoreactivity (CPR) response to the oral glucose tolerance test (OGTT) was examined up to 48 mo in 30 islet cell antibody-positive (ICA+), non-insulin-dependent diabetes mellitus (NIDDM) subjects (15 men, 15 women) who were matched for age, duration of diabetes, and mode of treatment. The subjects were recruited from 2858 NIDDM patients screened for ICA between 1980 and 1984. In male NIDDM subjects, CPR levels to OGTT decreased insidiously, and 8 of 15 men developed the insulin-dependent state with abolished CPR. Only 2 female NIDDM subjects progressed to the insulin-dependent state (P less than .05, women vs. men). Thus, CPR in female subjects tended to decrease less than in male subjects. There were no significant differences between the two groups in human leukocyte antigens (HLA) or titer of ICA during the follow-up period. These results suggest that maleness is a major risk factor for slowly progressive beta-cell dysfunction in adult-onset insulin-dependent diabetes mellitus (IDDM). Topics: Adult; Autoantibodies; Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucose Tolerance Test; HLA Antigens; Humans; Islets of Langerhans; Longitudinal Studies; Male; Risk Factors; Sex Factors | 1989 |
Influence of therapy-induced insulin antibodies on glycemic control in type 1 diabetes mellitus.
Topics: Adolescent; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Antibodies | 1989 |
Seasonality of type 1 (insulin-dependent) diabetes mellitus: values of C-peptide, insulin antibodies and haemoglobin A1c show evidence of a more rapid loss of insulin secretion in epidemic patients.
According to month of diagnosis, 165 children who developed Type 1 (insulin-dependent) diabetes mellitus at the age of 0-16.2 years (mean +/- SD, 7.6 +/- 4.1 years) could be divided into 69 patients diagnosed during peak seasons (epidemic cases) and 96 patients diagnosed during months of low incidence (non-epidemic cases). Seasonality of onset of symptoms and of diagnosis was observed in both sexes in all age groups. The patients diagnosed during peak seasons had shorter duration of symptoms (13.2 +/- 8.1 days) as compared to 22.9 +/- 10.3 days; p less than 0.001 in the patients diagnosed during months of low incidence. At diagnosis, 88.4% (61/69) of the epidemic group had ketonuria as compared to 71.9% (69/96); p less than 0.06 in the non-epidemic patients. The values of C-peptide, insulin antibodies, haemoglobin A1c and HLA-DR phenotype frequencies in the 69 epidemic patients were compared with those of the 96 non-epidemic patients. In the epidemic patients, the C-peptide values of 0.11 +/- 0.05 mmol/l at diagnosis had increased to 0.12 +/- 0.05 mmol/l at one month and 0.13 +/- 0.06 mmol/l at 3 months. These values were significantly lower (p less than 0.001) than in the non-epidemic patients at the same time points: 0.17 +/- 0.08 nmol/l; p less than 0.001, 0.23 +/- 0.11 nmol/l; p less than 0.001, and 0.22 +/- 0.10 nmol/l.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infant; Insulin; Insulin Antibodies; Insulin Secretion; Male; Seasons; Sex Factors; Sweden | 1989 |
[Studies on urinary C-peptide excretion in normal children and children with insulin-dependent diabetes mellitus].
In 115 normal children (3 to 14 years old) and 143 children with insulin-dependent diabetes mellitus (6 to 15 years old), the urinary C-peptide immunoreactivity) was measured for evaluation of the pancreatic B cell function. The urinary C-peptide excretions during O-GTT corresponded to the change of serum C-peptide levels in normal children (n = 27) and the mean value of the excretions in younger children was significantly low. Age did not significantly affect basal serum C-peptide levels (ng/ml) and urinary C-peptide excretions (micrograms/h) before O-GTT, but significant differences in serum sigma C-peptide (ng/ml) and urinary C-peptide (micrograms/3 h) during O-GTT were noted between the younger group and the older group (p less than 0.01). In 39 normal children on an inactive routine, mean values of the 24 h urinary C-peptide for children aged from 3 to 6, 7 to 10 and from 11 to 14 years old, were 28.2 +/- 12.6 micrograms/day, 32.3 +/- 8.4 micrograms/day and 37.6 +/- 10.6 micrograms/day (mean +/- SD) respectively with significant differences according to age (younger group vs older group, p less than 0.05). The effects of daily routine on 24 h urinary C-peptide were studied in normal children. In children on an active routine, the C-peptide excretion was significantly less than in the same individuals on an inactive routine (26.9 +/- 9.9 micrograms/day vs 34.3 +/- 14.5 micrograms/day, p less than 0.01). In children with insulin-dependent diabetes mellitus, 24 h urinary C-peptide excretion was studied to evaluate residual pancreatic B cell function. Urinary C-peptide was measurable in 47 of the 143 diabetic children, suggesting that most of the pancreatic B cells had deteriorated in the other 96 patients. In the 96 patients without B cell function, the averages of daily dose of insulin and 24 h-U.glucose/TAG ratio were significantly higher than those in the 47 patients who had pancreatic B cell function estimated by measuring urinary C-peptide (p less than 0.001). In additional studies on the 43 diabetic children with residual pancreatic B cell function, who had had the disease for five years or less, the 24 h urinary C-peptide excretion (micrograms/day) correlated weakly but significantly with the duration of the disease (r = -0.28, p less than 0.05). Patients who had had the disease longer and who were controlled with larger doses of insulin had less of the 24 h urinary C-peptide.(ABSTRACT TRUNCATED AT 400 WORDS) Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Pancreatic Function Tests | 1989 |
Metabolic effect of islet B-cell function in insulin-treated diabetes.
We studied the relationship between endogenous insulin secretion and fasting levels of plasma free fatty acids (FFA), plasma acetoacetate plus plasma 3-hydroxybutyrate (total ketone bodies), blood glucose, and HbA1 in 132 diabetic outpatients treated with conventional insulin regimens. Patients were divided into four groups according to plasma C-peptide concentration after intravenous stimulation with glucagon: one group with C-peptide stimulation less than 0.06 nmol/l, one group with C-peptide stimulation 0.06- less than 0.32 nmol/l, one group with C-peptide stimulation 0.32- less than 0.60 nmol/l, and one group with C-peptide stimulation greater than 0.60 nmol/l. According to clinical criteria the prevalence of insulin-dependent diabetes mellitus was approximately 90% in patients with C-peptide stimulation less than 0.32 nmol/l, approximately 25% in patients with C-peptide stimulation from 0.32- less than 0.60 nmol/l, and approximately 10% in patients with C-peptide stimulation greater than 0.60 nmol/l. All metabolic variables were significantly higher in patients without detectable C-peptide in plasma when compared to values found in patients with C-peptide stimulation from 0.06- less than 0.32 nmol/l. These two patient groups also had similar peripheral plasma free insulin levels and were comparable according to age, sex, and body mass index.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Fatty Acids, Nonesterified; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Ketone Bodies; Male; Middle Aged | 1989 |
[An improvement in insulin efficacy in patients with type-1 diabetes mellitus following treatment using an insulin infusion pump].
In 8 patients with diabetes mellitus type I two methods for intensified insulin treatment were compared: method of numerous insulin applications and treatment with a subcutaneous insulin pump (Microjet model of "Miles" company). The following were taken into consideration: daily insulin dose, residuary beta-cell secretion (determined by a venous Tolbutamide test and dynamic follow up of C-peptide), peripherial insulin efficiency (M) determined in vivo by an euglycemic hyperinsulinemic clamp-technique (Biostator). The infusion pump treatment imitates the beta-cell function better than the numerous insulin applications. This method of treatment helps in overcoming the insulin deficiency and the jatrogenic hyperinsulinemia and as a result the metabolic compensation and insulin efficiency are improved. Topics: Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Drug Evaluation; Humans; Insulin; Insulin Infusion Systems; Tolbutamide | 1989 |
Fasting plasma C-peptide, glucagon stimulated plasma C-peptide, and urinary C-peptide in relation to clinical type of diabetes.
Many patients with Type 2 (non-insulin-dependent) diabetes mellitus are treated with insulin in order to control hyperglycaemia. We studied fasting plasma C-peptide, glucagon stimulated plasma C-peptide, and 24 h urinary C-peptide in relation to clinical type of diabetes in 132 insulin treated diabetic subjects. Patients were classified clinically as Type 1 (insulin-dependent) diabetic subjects in the presence of at least two of the following criteria: 1) significant ketonuria, 2) insulin treatment started within one year after diagnosis, 3) age of diagnosis less than or equal to 40 years, and 4) weight below 110% of ideal weight of the same age and sex. Eighty patients were classified as Type 1 and 52 as Type 2 diabetic subjects. A second classification of patients into 6 C-peptide classes was then performed. Class I consisted of patients without islet B-cell function. Class II-VI had preserved islet B-cell function and were separated according to the 20%, 40%, 60% and 80% C-peptide percentiles. The two classifications of patients were compared by calculating the prevalence of clinical Type 1 and Type 2 diabetes in each of the C-peptide classes. This analysis showed that patients with a fasting plasma C-peptide value less than 0.20 nmol/l, a glucagon stimulated plasma C-peptide value less than 0.32 nmol/l, and a urinary C-peptide value less than 3.1 nmol/l, or less than 0.54 nmol/mmol creatinine/24 h, or less than 5.4 nmol/24 h mainly were Type 1 diabetic patients; while patients with C-peptide levels above these values mainly were Type 2.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucagon; Humans; Insulin; Insulin Secretion; Male | 1989 |
Type 1 (insulin-dependent) diabetes in Japanese children is not a uniform disease.
The initial course of Type 1 (insulin-dependent) diabetes mellitus was studied in two groups of Japanese children, i.e. 21 patients with abrupt onset (Group A) and 19 patients detected by urine glucose screening at school with minimal or no symptoms (Group B). There was no statistical difference in mean age at diagnosis between Group A and B (11 +/- 3 years vs 11 +/- 3 years). Group A patients revealed a rapid deterioration of pancreatic B-cell function, but there was evident recovery of the B-cell function from 3 to 9 months following initial treatment. The B-cell capacity in Group B was self maintained until 24 months after diagnosis. Thereafter, even these patients exhibited a progressive decline in the B-cell function. The two groups had a similar incidence of islet cell antibodies at diagnosis (58% vs 69%). However, human leukocyte antigen studies revealed that patients in Group A had a significantly higher prevalence of DR4 and DRW9 than those in Group B (p less than 0.01). These results suggest that in Japanese children there are two forms of diabetes, an abrupt and a slow onset form, which are clinically different and which also seemed to be genetically independent types, or possibly the same disease diagnosed at different stages. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; HLA-D Antigens; Humans; Insulin; Islets of Langerhans; Japan; Male | 1989 |
Plasma zinc concentrations during the first 2 years after diagnosis of insulin-dependent diabetes mellitus: a prospective study.
Studies of zinc status in insulin-dependent diabetes mellitus (IDDM) have shown contradictory results. Zinc is essential for many enzymes involved in the human metabolism and may play a role in the biosynthesis and storage of insulin in the B-cell. We therefore prospectively followed 26 patients (14 males and 12 females) with newly diagnosed IDDM in order to determine the plasma zinc variation at the time of diagnosis and after 1, 3, 6, 12 and 24 months. Seventy-two healthy persons (36 males and 36 females) served as controls. Only minor differences in plasma zinc were demonstrated during the first 2 years of IDDM. A sex difference was found in healthy controls but only after 24 months in the diabetics. Quantitative changes of the B-cell function, development of insulin antibodies, age, body weight and serum albumin did not correlate with the course of plasma zinc. Topics: Adolescent; Adult; Age Factors; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin Antibodies; Islets of Langerhans; Male; Middle Aged; Prospective Studies; Serum Albumin; Sex Factors; Zinc | 1989 |
Erythrocyte insulin binding in a family with hereditary motor sensory neuropathy (Charcot-Marie-Tooth) with superimposed insulin-dependent type I diabetes mellitus.
Studies on erythrocyte insulin receptors were performed in a family with hereditary motor sensory neuropathy (Charcot-Marie-Tooth) with superimposed type I diabetes mellitus. The maximum specific insulin binding of the erythrocytes was high and the increase was shown to be due to increased affinity of the insulin receptor to erythrocytes. Topics: Adolescent; Adult; Aged; C-Peptide; Charcot-Marie-Tooth Disease; Diabetes Mellitus, Type 1; Erythrocytes; Female; Humans; Insulin; Muscular Atrophy, Spinal; Receptor, Insulin; Reference Values | 1989 |
The behaviour of pyruvate dehydrogenase in circulating lymphocytes from diabetic children.
The basal and total pyruvate dehydrogenase activities were assayed in circulating lymphocytes from children with juvenile diabetes at diagnosis and after five days of insulin therapy and from control subjects. In untreated diabetic children, basal and total pyruvate dehydrogenase activities were deeply decreased and both showed very similar values; whereas, in control subjects basal activity was about 30% lower than total activity. In diabetic patients treated with insulin (in vivo situation), both basal and total activity levels were equal or even higher than those of the control subjects. The incubation of lymphocytes from diabetic patients with insulin (5 microU/ml) (in vitro situation) stimulates, but less than in vivo, the basal and total pyruvate dehydrogenase activities. Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Insulin; Ketone Bodies; Lymphocytes; Male; Pyruvate Dehydrogenase Complex | 1989 |
[Factors affecting stability in the course of insulin-dependent diabetes mellitus].
The patients with diabetes mellitus type I show a different course of the disease. In one group of patients diabetes runs a smooth and metabolic compensation is easily achieved and maintained. In another group of patients metabolic compensation is very difficult to achieve or it cannot be achieved at all. In 51 patients with diabetes mellitus type I the role of the residual beta-cell secretion and the insulin sensitivity for the stability of diabetes is studied. The endogenic insulin insufficiency, iatrogenic hyperinsulinemia and the related peripheral insulin resistance are the basic factors determining the stability of the insulin-dependent diabetes mellitus. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Chronic Disease; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Insulin Infusion Systems; Insulin Resistance; Islets of Langerhans; Male; Middle Aged; Tolbutamide | 1989 |
Relationship of insulin autoantibodies to presentation and early course of IDDM in children.
Insulin antibodies have been documented before (insulin autoantibodies [IAAs]) and after (insulin antibodies) insulin administration in children with new-onset insulin-dependent diabetes mellitus (IDDM). Whereas the relationship of IAA to various factors at presentation has been studied in some detail, little is known about their relationship to events during the 1st yr after diagnosis. Furthermore, the course and factors affecting insulin-antibody response to human insulin administration in children with newly diagnosed IDDM remain poorly defined. To study these questions, we measured serum glucose, pH, bicarbonate, C-peptide, and IAA at diagnosis in 84 children between 0.5 and 18 yr of age. Basal and peak C-peptide responses to Sustacal ingestion, glycosylated hemoglobin (HbA1c), and IAA were then measured in 33 of these patients at 10 days and 1, 3, 6, and 12 mo after diagnosis. At presentation, IAAs were absent (binding below the mean + 3SD of the binding of control serums) in 51 patients (61%) and present (binding above the mean + 3SD) in 33 patients (39%). Multiple regression analysis showed a significant nonlinear relationship between IAAs and both age (P less than .005) and blood glucose (P less than .05) at onset. There was a stepwise increase in median insulin-antibody binding throughout the 1st yr. This increase was most marked during the 1st mo of insulin therapy and showed a statistically significant difference between successive measurements only during this period.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Antibody Formation; Autoantibodies; Bicarbonates; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Hydrogen-Ion Concentration; Infant; Insulin; Insulin Secretion | 1989 |
The effect of residual beta cell activity on menstruation and the reproductive hormone profile of insulin-dependent diabetics.
To investigate the cause of secondary amenorrhoea in insulin-dependent diabetes gonadotrophins, sex steroid hormone levels and residual beta cell activity (C-peptide index) were estimated in a group of 43 women with IDDM. Among 26 women with residual insulin secretion, the C-peptide positive (CpP) group, 5 had secondary amenorrhoea (CpP-Am); among 17 women without endogenous beta cell activity, the C-peptide negative (CpN) group 6 had secondary amenorrhoea (CpN-Am). In this study two different types of secondary amenorrhoea in insulin-dependent diabetics were observed. All CpP-Am women have the classical hormone profile of the polycystic ovary syndrome (increased (LH/FSH ratio, increased serum testosterone, decreased SHBG) together with a history of oligomenorrhoea and excess weight before the onset of diabetes. On the other hand, all CpN-Am women had decreased LH levels as well as low LH/FSH ratio and testosterone levels. These results strongly suggest that a lack of residual pancreatic beta cell activity influences hypothalamus-pituitary function in insulin-dependent diabetes. It might be concluded that PCOS is independent of diabetes while low LH amenorrhoea seems to be the consequence of diabetes and is strongly associated with a lack of residual insulin secretion. Topics: Amenorrhea; C-Peptide; Diabetes Mellitus, Type 1; Female; Gonadal Steroid Hormones; Gonadotropins, Pituitary; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Menstruation; Prolactin; Radioimmunoassay; Sex Hormone-Binding Globulin; Ultrasonography | 1989 |
Does residual insulin secretion (assessed by C-peptide concentration) affect lipid and lipoprotein levels in insulin-dependent diabetes mellitus?
1. Residual endogenous insulin secretion can be assessed by the circulating C-peptide concentration and is present in up to 15% of subjects with established insulin-dependent diabetes mellitus (IDDM). Its role in lipid metabolism in IDDM is not clearly defined. We examined the relationships between serum lipid and lipoprotein concentrations and the response of circulating C-peptide to a test meal in 205 subjects with IDDM. 2. Lipid and lipoprotein levels and glycaemic control did not differ significantly between patients with undetectable, low or high C-peptide responses. 3. High density lipoprotein (HDL) cholesterol and its subfractions were inversely related to concentrations of serum triacylglycerols (P less than 0.01-0.001), but not to C-peptide or glycated haemoglobin (HbA1) levels. Levels of HbA1 and triacylglycerols were correlated with one another (P less than 0.01). Analysis of variance revealed that differences in gender and triacylglycerol concentrations were the most important determinants of HDL and HDL2 cholesterol levels. C-peptide only exerted a weak effect on HDL2 cholesterol levels and no significant predictors of HDL3 cholesterol were found. 4. It is concluded that endogenous insulin secretion (assessed by C-peptide concentration) is relatively unimportant in modifying HDL metabolism in IDDM and that associated clinical features, in particular ambient hypertriglyceridaemia, are of greater importance. Topics: Adolescent; Adult; Aged; C-Peptide; Cholesterol, HDL; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Lipids; Lipoproteins; Male; Middle Aged; Triglycerides | 1989 |
Sandostatin, a new analogue of somatostatin, reduces the metabolic changes induced by the nocturnal interruption of continuous subcutaneous insulin infusion in type 1 (insulin-dependent) diabetic patients.
With the aim of assessing a new somatostatin analogue to prevent the metabolic changes induced by a 6-h nocturnal arrest of an insulin pump, nine C-peptide negative Type 1 (insulin-dependent) diabetic patients were submitted blindly to two interruptions (from 23.00 to 05.00 hours) of their continuous s.c. insulin infusion, once after a single s.c. injection at 23.00 hours of 50 micrograms SMS 201-995 (Sandostatin, Sandoz) and once after 0.9% NaCl. Plasma SMS 201-995 levels peaked at 24.00 hours and then declined with an elimination half-life averaging 144 +/- 15 min. Plasma glucagon and growth hormone levels were significantly reduced after SMS 201-995 whereas the progressive fall in plasma-free insulin levels from 23.00 to 05.00 hours was unaffected. In the control test, blood glucose levels tended to decrease slightly from 23.00 to 02.00 hours and then increased markedly from 02.00 to 05.00 hours (+5.3 +/- 1.5 mmol/l) while after SMS 201-995 they decreased significantly from 23.00 to 02.00 hours (-2.6 +/- 0.5 mmol/l), resulting in values below 3 mmol/l in seven subjects, but showed a secondary increase until 05.00 hours (+3.5 +/- 1.5 mmol vs 23.00 h; p less than 0.05 vs 0.9% NaCl). While the rises in plasma non-esterified fatty acid and glycerol levels were not reduced by SMS 201-995, the increase in plasma 3-hydroxbutyrate levels, although similar from 23.00 to 02.00 hours, was significantly reduced from 02.00 to 05.00 hours (+77 +/- 20 vs +124 +/- 31 mumols.l-1.h-1; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Drug Administration Schedule; Fatty Acids, Nonesterified; Female; Glucagon; Glycerol; Growth Hormone; Humans; Hydroxybutyrates; Insulin; Insulin Infusion Systems; Male; Octreotide | 1989 |
B-cell responses to intravenous glucose and glucagon in non-diabetic twins of patients with type 1 (insulin-dependent) diabetes mellitus.
The B-cells of patients with recently diagnosed Type 1 (insulin-dependent) diabetes may have no response to glucose when the response to glucagon is present but attenuated. This observation suggests that the recognition of glucose is more severely affected than that for non-glucose stimulants. To determine whether a similar selective decrease in glucose response was present before the onset of diabetes we studied two groups of non-diabetic identical twins of patients with recently diagnosed Type 1 diabetes: one group with complement-fixing islet cell antibodies who were at high risk of developing diabetes (four of the five have already developed diabetes) and a group without such antibodies at low risk of developing diabetes. In addition, a group of patients with chronic pancreatitis were studied to control for non-specific damage to the B-cell. Responses to i.v. glucose and i.v. glucagon were compared. Patients with chronic pancreatitis has similar responses to both glucose and glucagon and the responses did not differ from control subjects. The B-cells of the immune positive group showed evidence of pathology because the insulin and C-peptide responses to both stimuli were reduced when compared to either their control subjects or the immune negative twin group. However, the B-cell response to both glucose and glucagon in the immune positive twins was similar. Because the B-cell response to glucose was not less than that to glucagon, a selective destruction of the glucose recognition system cannot be a characteristic of all twins throughout the period before they develop Type 1 diabetes. Topics: Adult; Autoantibodies; Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Diseases in Twins; Female; Glucagon; Glucose; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Pancreatitis; Reference Values; Risk Factors; Twins, Monozygotic | 1989 |
[Effects of taking charge and education on the remission of insulin-dependent diabetes].
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Insulin; Patient Education as Topic | 1989 |
A comparison of direct measures of glycaemia and glycated blood proteins in insulin-dependent diabetes mellitus.
We have studied associations between various direct measures of glycaemia and glycated blood proteins in 113 subjects with insulin-dependent diabetes mellitus (IDDM), and examined whether or not the 'fructosamine' assay results were affected by differing patient serum concentrations of lipids, albumin or C peptide. Serum fructosamine correlated less closely with HbA1 (r = 0.44) than did HbA1 with glycated serum albumin (GSA) (r = 0.68). Serum fructosamine and GSA also were poorly correlated (r = 0.48). Although fructosamine, HbA1 and GSA correlated to a similar degree with fasting blood glucose (r range 0.34 to 0.37), GSA was most closely related to mean blood glucose (r = 0.39 vs. 0.30-0.35) and the M value (a marker of diurnal glycaemic instability) (r = 0.42 vs. 0.33-0.35). The serum concentration of fructosamine was not significantly affected by a variation in serum cholesterol, but tended to be lower in subjects with moderate hypertriglyceridaemia (p = 0.05). The fructosamine assay may be altered by moderately lipaemic serum but is not affected by serum albumin concentration in normoalbuminaemic patients with IDDM. Our study indicates, however, that GSA is a more reliable marker of short-term glycaemic control in IDDM than fructosamine. Topics: Adolescent; Adult; Aged; Blood Glucose; Blood Proteins; C-Peptide; Diabetes Mellitus, Type 1; Female; Fructosamine; Glycated Serum Albumin; Glycated Serum Proteins; Glycation End Products, Advanced; Glycoproteins; Glycosylation; Hexosamines; Humans; Hypertriglyceridemia; Insulin; Lipids; Male; Middle Aged; Serum Albumin | 1989 |
Effect of human proinsulin on blood glucose control and metabolic instability in type 1 diabetes mellitus.
The effect of human biosynthetic proinsulin (PRO) on blood glucose (BG) control and glucose excursions was studied in a nonrandomized design in eight patients with unstable type 1 diabetes mellitus and compared with that of human NPH insulin. Both preparations were injected subcutaneously twice daily for three days each in combination with small doses of regular insulin. All patients were kept in metabolic control during PRO treatment. Mean BG (mean of three days, 18 samples per day) was lower during PRO (mean +/- SE: 14.4 +/- 4.0 versus 11.4 +/- 3.0 mmol/l, p = 0.079). Inspection of individual data showed that four patients had similar BG profiles and mean daily BG concentrations with both preparations (12.3 +/- 1.1 vs 12.1 +/- 1.0 mmol/l), while the other four had significantly lower values during PRO (16.5 +/- 1.0 vs 10.1 +/- 1.1 mmol/l, p = 0.003). Metabolic instability (MAGE values) was similar during NPH and PRO (7.5 +/- 0.5 versus 7.0 +/- 0.5 mmol/l, H = 0.011, p = 0.88) when calculated for the entire group of patients. However, all patients with similar BG profiles during NPH and PRO treatment had smaller daily BG excursions on PRO (8.1 +/- 0.8 versus 6.6 +/- 0.6 mmol/l, p = 0.104, Wilcoxon test). The counterregulatory hormones, growth hormone and cortisol were not different between the two treatment periods or between the two groups. Plasma PRO concentrations (as determined through crossreaction in a C-peptide assay) did not correlate with the PRO dose (rxy = 0.508, p = 0.20), but correlated negatively with BG (rxy = 0.841, p = 0.009).. (1) Patients with type 1 mellitus can be kept in metabolic control during treatment with human PRO. (2) The dose of PRO considered equipotent to NPH insulin must be determined for each patient individually in order to avoid hypoglycemic attacks. (3) Although there was a tendency towards improved metabolic stability during PRO in some patients, this requires further investigations. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Growth Hormone; Humans; Hydrocortisone; Insulin; Male; Proinsulin; Recombinant Proteins | 1989 |
Influence of maternal metabolic control and insulin antibodies on neonatal complications and B cell function in infants of diabetic mothers.
Circulating insulin antibodies at birth and the degree of maternal metabolic control were measured in 68 infants of insulin-treated diabetic mothers. Their correlation with neonatal B cell function and with the clinical features of the infants was evaluated in order to better understand their influence on fetal outcome. Maternal metabolic control was assessed on the basis of blood glucose levels, glycosuria and the occurrence of hypoglycemia and/or ketonuria. All infants were clinically evaluated for gestational age, macrosomia, hypoglycemia, hyperbilirubinemia, hypocalcemia, and respiratory distress syndrome. Cord blood plasma glucose, C peptide, and IgG insulin antibodies were also measured. It was shown that poor maternal metabolic control was associated with a higher prevalence of fetal morbidity as well as with signs of B cell hyperfunction. Also the presence of circulating insulin antibodies correlated well with higher C peptide levels and with several neonatal complications. B cell hyperfunction, indicated by high C peptide levels in the infants of diabetic mothers, may possibly play a causal role in the pathogenesis of fetal morbidity. In conclusion, a good fetal outcome in insulin-treated diabetic pregnancies was associated with and may have depended upon: (1) good maternal metabolic control, and (2) absence or low levels of circulating insulin antibodies. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Fetal Blood; Glycated Hemoglobin; Glycosuria; Humans; Hypoglycemia; Immunoglobulin G; Infant, Newborn; Infant, Newborn, Diseases; Insulin; Insulin Antibodies; Islets of Langerhans; Ketone Bodies; Pregnancy; Pregnancy in Diabetics | 1989 |
Correlation between residual beta-cell function and islet cell antibodies in newly diagnosed type I diabetes. Follow-up study.
To establish whether there is a correlation between the autoimmune response to the islets and beta-cell function during the initial stages of type I (insulin-dependent) diabetes, and islet cell antibody (ICA) titer and C-peptide levels (fasting and glucagon stimulated) were determined in 39 newly diagnosed patients at onset of diabetes and every 3-6 mo for 2 yr. ICAs were detected in 74% of the patients, and beta-cell function was detected in 84% of the patients at onset. The ICA+ and ICA- groups had similar C-peptide values at diagnosis and at 3 mo, but from 6 mo on, the ICA+ group consistently showed a tendency to lose C-peptide secretory capacity more quickly when assessed by fasting and glucagon-stimulated C-peptide levels (ICA+ vs. ICA- fasting C-peptide levels at 18 and 24 mo, P = .013 and .017, respectively; ICA+ vs. ICA- glucagon-stimulated C-peptide levels at 6, 18, and 24 mo, P = .023, .007, and .028, respectively). The initial ICA titer had the highest predictive value on the outcome of beta-cell function (P = .04), and patients with complement-fixing ICAs did not behave differently from the general ICA+ group. This correlation between beta-cell function and ICA titer supports the role of autoimmunity in the pathogenesis of type I diabetes and has important implications for the design of immunotherapy trials. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glucagon; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Parietal Cells, Gastric; Thyroid Gland | 1989 |
Persistence of anti-islet ADCC after manifestation of type-1 (insulin-dependent) diabetes.
ADCC (antibody-dependent cellular cytotoxicity) against xenogenic islets in vitro has frequently been found with mononuclear blood cells and heat inactivated autologous serum from newly diagnosed Type-1 diabetics. Anti-islet ADCC, as measured by enhanced 51Cr-release of islets after a 6h-incubation, leads to functional alteration of islets such as a decrease in insulin content and in leucine incorporation. In a follow-up investigation over at least three years it was demonstrated that anti-islet ADCC in vitro disappears, if there is no more C-peptide secretion in vivo. Furthermore, anti-islet ADCC has also not been found in long-term Type-1 diabetics who had no C-peptide secretion but an acutely stimulated immune system due to infectious diseases. An acute immunocytolytic process against pancreatic beta cells in vivo seems to be the precondition for anti-islet ADCC in vitro. Topics: Adolescent; Adult; Antibody-Dependent Cell Cytotoxicity; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Leucine; Male | 1989 |
Different percentages of CD8+ lymphocytes in long-term type 1 diabetics with and without residual beta cell function.
About 15% of Type 1 diabetics display residual beta cell function after more than 10 yr duration of diabetes, indicating that the disease mechanisms have stopped before all beta cells are destroyed. Peripheral blood lymphocytes were studied from such patients, 11 females and 12 males, 29 +/- 1 yr old, who had had diabetes for 14 +/- 1 yr. A completely matched group of 23 Type 1 diabetics with the same disease duration, but without residual beta cells, were also studied together with a healthy control group. Lymphocytes were marked with monoclonal OKT antibodies and examined by flow cytometry (FACS). There was no difference between the three groups in the absolute number of lymphocytes and helper T-cells (CD4+:40.2 +/- 1.3 vs. 40.4 +/- 1.3 vs. 41.1 +/- 1.8%). In respect of CD8+ (suppressor/cytotoxic) T-cells, the diabetics without beta cells showed 25.9 +/- 1.0%, significantly less than both the patients with preserved beta cell function (29.0 +/- 0.9%, p less than 0.02) and the controls (29.5 +/- 1.3%, p less than 0.02). CD3+ (pan) T-cells showed parallel changes (67.8 +/- 1.5 vs. 71.0 +/- 1.4 vs. 72.2 +/- 1.4%, p less than 0.05). The metabolic state was similar in the two patient groups, and there was no correlation between metabolic and immunological parameters. It is unknown whether the normalization of the T-cell subpopulation, especially the CD8+ lymphocytes, in patients with residual beta cell function at a point when the disease process is apparently at rest, is of causal significance, or of only marker significance. Topics: Adult; Antigens, CD; Blood Glucose; C-Peptide; CD4 Antigens; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Reference Values; Sex Factors; T-Lymphocytes | 1989 |
Serum immunoreactive trypsin in tropical pancreatic diabetes syndrome.
Fifteen patients with tropical pancreatic diabetes syndrome (TPDS), 16 insulin-dependent diabetics (IDD), 27 non-insulin-dependent diabetics (NIDD) and 14 normal subjects, all from India, were investigated for markers of beta-cell (C-peptide) and exocrine (immunoreactive trypsin; IRT) reserve. IRT and C-peptide concentrations were the lowest in TPDS, lower than normal in IDD, and not significantly different from normal in NIDDs. There was a highly significant correlation (rs = 0.93; P less than 0.0001) between IRT and C-peptide (measured in 50% of patients and controls) concentrations when all diabetic groups were combined. Such a correlation was absent when TPDS patients were considered in isolation, largely because of the markedly low IRT concentration. Fourteen of 15 patients (93%) with TPDS had subnormal IRT concentrations, of which 11 had IRT values of less than 50 micrograms/L. These IRT values are similar to those previously reported in cystic fibrosis. Only 6 of 16 IDDs (38%) had subnormal IRT concentrations, of which only one was below 50 micrograms/L. These data suggest that exocrine pancreatic reserve is markedly diminished in TPDS and that a subnormal IRT concentration may be a useful biochemical marker for this form of diabetes. Topics: Adolescent; Adult; Biomarkers; C-Peptide; Calculi; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; India; Male; Middle Aged; Pancreatic Diseases; Tropical Climate; Trypsin | 1989 |
Cyclosporin-A treatment for early insulin-dependent diabetes mellitus: first experience in Israel.
Topics: Adult; C-Peptide; Creatinine; Cyclosporins; Diabetes Mellitus, Type 1; Drug Evaluation; Female; Humans; Israel; Male; Radioimmunoassay; Time Factors | 1989 |
Pancreatic hormone secretion in chronic pancreatitis without residual beta-cell function.
Hormonal responses (glucagon, pancreatic polypeptide and somatostatin) to iv glucagon, iv arginine, and ingestion of a mixed meal were investigated in 6 patients with insulin-dependent diabetes secondary to chronic pancreatitis without beta-cell function, in 8 Type I (insulin-dependent) diabetics without beta-cell function, and 8 healthy subjects. No significant differences were found between the two diabetic groups regarding glucagon responses to arginine and meal ingestion. In the patients with diabetes secondary to chronic pancreatitis compared with Type I diabetics and normal controls, the pancreatic polypeptide concentrations were significantly lower and somatostatin concentrations were significantly higher after glucagon, arginine and a mixed meal. Thus, pancreatic glucagon secretion was preserved in patients with insulin-dependent diabetes secondary to chronic pancreatitis, having no residual beta-cell function. These findings suggest that pancreatic glucagon deficiency is not absolute in insulin-dependent diabetes secondary to chronic pancreatitis. A high level of somatostatin may contribute to a lower blood glucose level in patients with chronic pancreatitis. Topics: Adult; Arginine; Blood Glucose; C-Peptide; Chronic Disease; Diabetes Mellitus, Type 1; Food; Glucagon; Humans; Insulin; Islets of Langerhans; Middle Aged; Pancreatic Polypeptide; Pancreatitis; Somatostatin | 1988 |
Recovery of human fetal pancreas after one year of implantation in the diabetic patient.
Between one and six cultured human fetal pancreata were allografted into five insulin-dependent diabetic recipients and their progress monitored for a year on each occasion. To prevent rejection the tissue was cultured for 1-3 weeks before transplantation, the HLA-DR antigens of the donor tissue were matched with those of the recipient when a single pancreas was used, and four of the recipients were immunosuppressed, three because of coexisting renal grafts. Graft function was observed transiently in one of the recipients. In three others human fetal pancreas was recovered 9-14 months after transplantation, although it was being slowly rejected during this time. Beta cells were present in the graft but did not function adequately to enable immunoreactive C-peptide to be measured in peripheral blood. The issues of rejection and immaturity of the human fetal pancreas will need to be surmounted if the potential of the human fetal pancreas to normalize blood glucose levels in diabetic man is ever to be realized. Topics: C-Peptide; Diabetes Mellitus, Type 1; Fetus; Follow-Up Studies; Forearm; Graft Survival; Humans; Magnetic Resonance Imaging; Pancreas; Pancreas Transplantation; Polymorphism, Restriction Fragment Length | 1988 |
[Development of insulin reserves in the first 18 months in the insulin-dependent diabetic with or without remission of insulin-dependence].
It seems rational to consider that residual insulin secretion is one of the factors which determine the short-term course of inaugural type I diabetes. But what about the mid-term course? We evaluated prospectively the insulin reserve (fasting and post-prandial C peptide) in 52 patients throughout the subsequent development of the disease. The patients (36 men, 16 women, mean age 35 years), who presented with ketonuria and weight loss, received a 10-day course of intensive insulin therapy, after which a remission of insulin dependence was observed in 40 of them (77 per cent). These 40 patients differed from those who had no such remission in that they were heavier and had a better initial insulin secretion. There was no significant difference between the two groups with regards to immunogenetic markers (presence of anti-islet antibodies 28/35 vs 8/12, DR3 and/or DR4 tissue group 27/37 vs 8/10). Following intensive insulin therapy, the C peptide value was consistently increased. At 6, 12 and 18 months the insulin secretion in patients of the remission group remained stable and always higher than that of patients who did not have a remission and whose insulin secretion collapsed at 18 months. Another characteristic of the remission group was that C peptide secretion could be stimulated by meals throughout the follow-up period (post-prandial C peptide at 18 months: 0.63 nmol/l). It is concluded that residual insulin secretion is one of the most effective predictive factors of remission when type I diabetes is first diagnosed and remains stable for the first 18 months of the disease in patients who show a remission. Topics: Adolescent; Adult; Aged; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged; Remission, Spontaneous; Time Factors | 1988 |
Presence of insulin autoantibodies at clinical diagnosis of diabetes mellitus type I predicts loss of beta cell function.
Recently the spontaneous development of insulin autoantibodies (IAA) has been detected in patients at diagnosis of Type I diabetes mellitus before the beginning of insulin treatment. The present study was undertaken to investigate if the presence of IAA at clinical onset of IDDM may act as a new marker of the beta cell function. The results obtained showed that IAA were present in 44% of newly diagnosed diabetic patients before therapy. Patients without IAA displayed a higher C-peptide secretion than those with IAA, at six months (12.11 +/- 5.08 versus 5.88 +/- 3.25 ng/ml/10 min.)(X +/- SD) and at twelve months (10.45 +/- 3.05 versus 4.90 +/- 5.25 ng/ml/10 min)(X +/- SD) of the follow up period. HbA1 levels, and insulin requirements were similar in both groups (IAA+ and IAA-). We conclude that the presence of insulin autoantibodies at clinical diagnosis, before initiating insulin treatment, may well predict the loss of the beta cell function. Topics: Adolescent; Adult; Autoantibodies; Biomarkers; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Prognosis | 1988 |
[The importance of strict control of blood glucose at the onset and during the remission stage in newly diagnosed diabetic children].
Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Infusion Systems; Male | 1988 |
Glucagon-stimulated and postprandial plasma C-peptide values as measures of insulin secretory capacity.
Basal, postprandial (2 h after breakfast), and glucagon-stimulated plasma C-peptide concentrations were determined in a group of 36 adult diabetic patients. Basal and postprandial C-peptide values were measured on consecutive days to estimate the degree of variation of C-peptide secretion. In a subgroup of 15 diabetic patients treated chronically with diet and oral hypoglycemic agents (sulfonylureas or a combination of sulfonylureas and metformin), we studied whether administration of sulfonylureas immediately before breakfast had any effect on postprandial C-peptide values. Absolute differences between two consecutive fasting C-peptide concentrations in insulin-requiring patients were less than 0.1 nM in all but 1 patient, in whom the difference was 0.18 nM. In subjects treated with oral hypoglycemic agents the median difference was 0.12 nM (range 0-0.38 nM). Absolute differences between two consecutive postprandial C-peptide concentrations were all less than 0.1 nM in insulin-requiring patients. No significant difference was found between postprandial C-peptide concentrations with or without preceding administration of oral hypoglycemic agents (medians 1.35 and 1.30 nM, respectively). Glucagon-stimulated C-peptide concentrations were somewhat higher than the postprandial values. However, equal discrimination between insulin-requiring and non-insulin-requiring diabetic patients was found by measuring postprandial or glucagon-stimulated C-peptide concentrations. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Eating; Fasting; Glucagon; Humans; Insulin; Insulin Secretion; Middle Aged | 1988 |
Porcine and human insulin absorption from subcutaneous tissues in normal and insulin-dependent diabetic subjects: a deconvolution-based approach.
The mechanisms of sc insulin absorption are not understood, and models for interpreting in vivo data cannot be developed without gross simplification. To overcome this difficulty we developed a new approach which makes use of deconvolution analysis and does not require any model of the sc tissue. In five normal subjects and seven insulin-dependent diabetic (IDDM) patients endogenous insulin secretion was suppressed by means of a hypoglycemic glucose clamp procedure (approximately 2.8 mmol/L) sustained by a continuous insulin infusion (approximately 4 pmol/min.kg). A bolus injection of insulin (5.4 nmol) was administered iv, and plasma insulin concentrations were measured frequently for 2 h to assess iv insulin kinetics. Insulin then was injected sc in the abdominal region, and plasma insulin concentrations were measured for 8 h. Each subject was studied twice, with porcine and semisynthetic human insulin (Actrapid, Novo). The rate of insulin absorption was reconstructed by deconvolution from the plasma concentrations and iv insulin kinetic data. Linearity of the iv insulin kinetics, essential for deconvolution analysis, was confirmed by a dose-response study in the range of the measured concentrations (150-1800 pmol/L). In most instances, a two-compartment model was adequate to describe the iv response. The mean plasma insulin clearance rates were 15.5 +/- 1.9 (+/- SD) mL/min.kg (porcine) and 17.2 +/- 6.0 (human) in normal subjects and 20.7 +/- 8.8 (porcine) and 20.9 +/- 9.1 (human) in the IDDM patients. The rate of appearance of human insulin from sc tissue was faster than that of porcine insulin in both normal and IDDM subjects, but no significant differences were found in bioavailability, which was 55 +/- 12% (+/- SD; porcine) and 61 +/- 34% (human) in the normal subjects, and 84 +/- 28% (porcine) and 86 +/- 23% (human) in the IDDM patients. The rate of absorption and bioavailability were higher in the IDDM patients than in the normal subjects, a difference possibly related to increased sc blood flow in the IDDM patients. No differences were found with regard to glucose requirement values, normalized to plasma insulin concentrations, in agreement with the finding that the bioavailability of the two insulin species was similar. Topics: Adolescent; Adult; Animals; Biological Availability; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hypoglycemia; Injections, Subcutaneous; Insulin; Insulin Infusion Systems; Male; Swine | 1988 |
Residual beta-cell function and metabolic stability in insulin-dependent diabetes mellitus.
Using the modified sensitive method of measurement of urinary C-peptide immunoreactivity (CPR) excretion, we studied whether positive correlation between residual beta-cell function and metabolic consequence is present in insulin-dependent diabetes mellitus (IDDM) or not. After urinary CPR excretions were measured for 3 days in 40 IDDM, they were divided to three groups: group A, urinary CPR excretion less than 1 microgram/day (n = 16); group B, 1-4 micrograms/day (n = 15); group C, greater than or equal to 4 micrograms/day (n = 9). All subjects were treated with intensive insulin therapy for 1-2 months, and 1) fasting blood glucose (FBS) for one week, 2) 24-hr urinary sugar excretion (US) for one week, 3) M-value for daily variation of blood glucose, and 4) hemoglobin A1 (HbA1) were measured before and after intensive insulin treatment. And, we calculated mean and standard deviation (S.D.) of FBS and US. After intensive insulin therapy, a significant difference of the S.D. of FBS was seen between group A and group B (p less than 0.01). And, a significant difference of M-value was found between group A and group B (p less than 0.05). As significant differences were observed between group A and group B, which could not be divided into two groups by conventional CPR measurement, it seems likely that metabolic stability in IDDM mainly result from minimal remaining residual beta-cell function. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Glycosuria; Humans; Insulin; Islets of Langerhans; Kidney Function Tests; Middle Aged | 1988 |
A prospective study of glucose profiles, insulin antibody levels and beta cells secretory patterns in non-obese Ugandan diabetic subjects.
Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Calcinosis; Chronic Disease; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Insulin Antibodies; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Pancreatic Diseases; Prospective Studies; Uganda | 1988 |
Investigation of the prolonged hypoglycemic effect of human proinsulin in diabetes mellitus.
Human proinsulin possesses a clear hypoglycemic effect, the extent and kinetics of which were investigated in 8 insulin dependent diabetics. In addition, to adequate therapy with a controlled-release insulin, each patient received i.v. injections of insulin (e U) and proinsulin (9 U) on separate test days. After 9 U of proinsulin, the blood glucose decrease was delayed in comparison to 3 U of insulin. However, it reached identical maximum blood glucose decrease values. The elimination kinetics of proinsulin are delayed compared to insulin. There is a linear relation between the time and the reciprocal value of the measured insulin immuno-reactivity. The hypoglycemic effect of proinsulin which is protracted for hours corresponds to that of an extreme controlled-release insulin. Under certain conditions, proinsulin might therefore prove effective in the long-term treatment of the insulin-dependent diabetes mellitus. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Kinetics; Middle Aged; Proinsulin | 1988 |
Clinical investigations into the modification of the effect of endogenous and exogenous insulin by human proinsulin in type II and type I diabetics.
The investigation on hand leads to the conclusion that HPRO can additively increase the blood glucose lowering effect of endogenous and exogenously administered insulin. Etiologically the prolonged retention time of HPRO in the circulation - compared to HI - must be primarily discussed. In the further course the question arises to what extent traditional retard insulins would have to be replaced or supplemented by HPRO. Topics: Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Drug Interactions; Drug Therapy, Combination; Humans; Insulin; Insulin Infusion Systems; Middle Aged; Proinsulin | 1988 |
Influence of ciamexon on blood glucose and insulin requirement in newly manifested type I diabetics. Results of a pilot study.
Treatment with the selectively immunomodulatory drug 1-[2-methoxy-6-methyl-3-pyridinyl)methyl]-2-aziridine-carbonitrile (ciamexon, BM-42332), an aziridine derivative, of newly diagnosed type I diabetic patients is reported. In an open pilot study the treatment of Cx led to the independence of insulin in 33.3% of the treated patients. Topics: Adjuvants, Immunologic; Adolescent; Adult; Antibodies, Viral; Autoantibodies; Aziridines; Azirines; Blood Glucose; C-Peptide; Chemical Phenomena; Chemistry; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1988 |
The epidemiology of lost residual beta-cell function in short term diabetic children.
Using the country-wide Swedish childhood diabetes register 526 children, who had had diabetes for 6-30 months were traced for measurements of 24-hour urinary C-peptide. Lost beta-cell function was defined as a 24-hour urinary C-peptide excretion per kg body weight less than 10% of the mean for healthy children (less than 0.025 nmol/kg). The estimated cumulative incidence of lost beta-cell function was 0.64 at 30 months. The incidence of lost beta-cell function did not differ by sex. Neither was there any significant variation in season at onset for cases with lost beta-cell function. A significant age dependency was shown for the cumulative incidence of lost beta-cell function with the highest incidence in the young age groups, i.e. a reversed age dependency compared to that of clinical onset. In contrast to the clinical onset of diabetes no significant geographical variation was found for lost beta-cell function when comparing standardized morbidity ratios. The urinary C-peptide excretion was significantly correlated to age at onset but not to degree or duration of ketonuria at onset. It is concluded that there are striking differences when comparing the epidemiology of lost beta-cell function to that of clinical onset in terms of age, sex, seasonal and geographical variations. The timing of clinical onset may thus partly be determined by factors different from those determining the rate of fall in beta-cell function. Topics: Adolescent; Age Factors; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Islets of Langerhans; Male; Seasons; Sex Factors; Sweden | 1988 |
Urinary C-peptide: a useful tool for evaluating the endogenous insulin reserve in cohort and longitudinal studies of diabetes in childhood.
Increasing research into the remission phase of type I diabetes mellitus stresses the importance of a non-traumatic and reliable method for the evaluation of endogenous insulin production. We compared 24-h urinary C-peptide excretion (UCE) with plasma C-peptide values before and after stimulation with 1 mg glucagon in 24 type I diabetic children. Fasting plasma C-peptide values and stimulated plasma C-peptide values showed a linear correlation with 24 h UCE. Mean plasma C-peptide levels correlated inversely with the exogenous insulin dose. A slightly better correlation was found between the exogenous insulin dose and 24 h UCE. Control data of 24 h UCE were obtained from healthy siblings. A linear correlation with age was found up to 10 years of age above which UCE values seem to reach a plateau. This effect of age, as well as the frequency of sampling was taken into account in the derivation of 95% reference intervals for UCE. The measurement of 24 h UCE appears to be a useful parameter to assess endogenous insulin production in diabetic children, provided that age is taken into account. Topics: C-Peptide; Child; Cohort Studies; Diabetes Mellitus, Type 1; Glucagon; Glycosuria; Humans; Insulin; Ketone Bodies; Longitudinal Studies | 1988 |
Insulin autoantibodies are associated with islet cell antibodies; their relation to insulin antibodies and B-cell function in diabetic children.
Blood was drawn from 74 children, 3-16 years old, at diagnosis of Type 1 (insulin-dependent) diabetes and before the first insulin injection. Insulin autoantibodies were detected with a polyethylen-glycol-method in 27/74 (36.4%) and with an immuno-electrophoretic method in 6/74 (8.1%). Islet cell cytoplasmic antibodies detected by indirect immuno-fluorescence were found in 49/74 patients (66.2%), who included as many as 23 of the 27 patients with insulin autoantibodies determined with the polyethylen-glycol-method (p less than 0.01). The proportion of insulin autoantibody-positive patients who developed insulin antibodies during the first 9 months of insulin treatment was not significantly greater (51.8%) than that of insulin autoantibody-negative patients (44.6%), but patients with both islet cell antibodies and insulin autoantibodies at diagnosis produced more insulin antibodies during the first 9 months (p less than 0.05). There was no difference in fasting or meal stimulated serum C-peptide after 3, 9 or 18 months as related to occurrence of insulin autoantibodies and/or islet cell antibodies. The correlation between insulin autoantibodies and islet cell antibodies indicates that both types of autoantibodies reflect the same immunological process, although the lack of correlation to C-peptide may indicate that they play a minor causal role. In addition, the results show that patients with an active autoimmune process evidently tend to produce more insulin antibodies during the first months of insulin treatment, but the islet cell antibodies and insulin autoantibodies-positive patients had at least as good residual B-cell function as patients without autoantibodies at diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin Antibodies; Islets of Langerhans; Male | 1988 |
Factors influencing the magnitude, duration, and rate of fall of B-cell function in type 1 (insulin-dependent) diabetic children followed for two years from their clinical diagnosis.
The pattern of fall in B-cell function measured as plasma and 24 h urinary C-peptide excretion, as well as levels of islet cell antibodies, insulin antibodies and metabolic parameters, were followed for two years in 39 children aged 1-17 years prospectively from clinical onset of Type 1 (insulin-dependent) diabetes. At onset 32/36 patients had measurable plasma C-peptide (median 0.13 nmol/l). Maximum values of fasting and postprandial plasma C-peptide were reached at a median duration of three months. Thereafter both plasma and urinary C-peptide declined linearly. The median value of the rate of fall in postprandial plasma C-peptide was 0.019 nmol.1-1.month-1. Age at onset was positively correlated to the maximum value of postprandial plasma C-peptide in each patient (rs = 0.57, p = 0.0001) and throughout the observation time positively correlated to fasting and postprandial C-peptide and to the 24 h urinary C-peptide excretion (rs range 0.35-0.70, p = 0.03-0.0001). The rate of fall of postprandial C-peptide was unrelated to age at onset and was strikingly parallel in different age groups. Islet cell antibodies were present in 87% of the patients at onset and decreased to 38% at 24 months. Islet cell antibody titres were not correlated to age at onset or to plasma or urinary C-peptide at any single observation. However, islet cell antibody negative patients had significantly higher (p less than 0.05) postprandial plasma C-peptide values at 1, 9, and 12 months of duration, compared to islet cell antibody positive patients.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Follow-Up Studies; Glycated Hemoglobin; Humans; Infant; Insulin Antibodies; Islets of Langerhans; Male | 1988 |
Metabolic state does not influence lymphocyte subsets in type 1 diabetic patients.
In most studies the distribution of peripheral lymphocyte subsets at diagnosis of type 1 diabetes has been found to be altered. Lymphocyte subpopulations were therefore studied during longitudinal changes in the glycaemic control of 11 type 1 diabetics to investigate whether poor metabolic status affects these results. To avoid any influence of the etiopathogenetic mechanisms, the patients studied had a disease duration of 10 +/- 2 (SEM) years and all but one had no residual beta-cell function. The patients were selected randomly amongst those with a long record of poor glycaemic control and at the first examination they had a mean fasting blood glucose of 15 +/- 1 mmol/l and a mean glucosuria of 67 +/- 11 g/24 h. They were then hospitalized and strictly regulated using pump treatment, resulting in a massive reduction in glucosuria (0 +/- 0 g/24 h) and fasting blood glucose (6 +/- 1 mmol/l) at a second examination a week later. Five of the patients were tested for a third time 35 +/- 4 days later and were still in very good glycaemic control. Peripheral lymphocytes were labelled with monoclonal antibodies and examined by flow cytometry (FACS). Neither CD3+ (pan) T-lymphocytes, CD4+ (helper) T-cells, CD8+ (suppressor/cytotoxic) T-cells, the relation between CD4+ and CD8+ T-cells, nor the total amount of lymphocytes, changed significantly between the first, second, and third examination. None of the results were significantly different from those of healthy controls. There was no correlation between any of the immunological and metabolic parameters. It is concluded that metabolic influence on the distribution of lymphocyte subsets is unlikely. Topics: Adult; Antibodies, Monoclonal; Antigens, Surface; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Insulin; Male; T-Lymphocytes | 1988 |
Negative correlation between ICA persistence and beta cell restoration after IDDM diagnosis.
We have studied 27 insulin-dependent diabetic patients since diagnosis for a period of six months; at diabetes onset and later on, ICA were found in 17 of them, whereas they were undetectable in 10 patients: age was remarkably homogeneous in the two groups. At diabetes onset, no significant differences were found in insulin requirement between ICA positive and ICA negative patients; however, six months after diagnosis, we observed that insulin requirement to keep metabolic control was significantly higher in ICA positive than in ICA negative subjects (0.515 +/- 0.2 U/Kg versus 0.22 +/- 0.15 U/Kg, p less than 0.001). Only one remission has been detected in ICA positive group (insulin requirement less than 0.25 U/Kg), while four ICA negative patients had complete remission and three had partial remission. ICA positive patients showed fasting C-peptide values higher than ICA negative (0.5 +/- 0.28 ng/ml versus 1.4 +/- 0.5 ng/m.; p less than 0.001, at rest; 1.1 +/- 0.6 ng/ml; versus 2.6 +/- 1.0 ng/ml, 6 minutes after stimulus; p less than 0.05). Our study suggests that presence and persistence of ICA may be considered an early and predictive marker for a worse beta cell function restoration resulting in a higher insulin requirement. Topics: Adolescent; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; HLA Antigens; Humans; Insulin; Islets of Langerhans; Male | 1988 |
[Secondary failure to oral hypoglycemic drugs: islet cell function determined by urinary C-peptide].
Topics: C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Insulin; Insulin Secretion; Islets of Langerhans; Male; Obesity | 1988 |
Plasma glucose response after intravenous injection of tolbutamide in insulin-treated type I and type II diabetic patients.
To estimate the residual beta-cell function, plasma glucose and C-peptide response to an intravenous injection of tolbutamide were observed in seven Type I (insulin dependent) and nine Type II (non-insulin dependent) diabetic patients on insulin therapy. Fasting plasma glucose in the patient was controlled below 11 mmol/l by conventional insulin therapy, and 1 g of tolbutamide was intravenously injected. In the serum C-peptide response following tolbutamide injection, seven of nine Type II diabetics showed the peak values of serum C-peptide more than 0.3 nmol/l from 20 min to 60 min after the load, and Type I diabetics gained the peak values less than 0.3 nmol/l except one patient. The decrease of plasma glucose within 60 min after tolbutamide injection was more than 20% of the basal level in eight of nine Type II diabetics, and in all of seven Type I diabetics the decrease did not exceed 15%. Both serum C-peptide and plasma glucose after tolbutamide load responded differently between Type I and Type II diabetics on insulin therapy, and it was thought that tolbutamide load-glucose response test may be a useful method to estimate the residual beta-cell function in the diabetics. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Injections, Intravenous; Insulin; Male; Middle Aged; Tolbutamide | 1988 |
Pancreatic transplantation.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucocorticoids; Graft Survival; Humans; Immunosuppressive Agents; Pancreas; Pancreas Transplantation | 1988 |
Clinical features of diabetes in the young as seen at a diabetes centre in south India.
This study reports on the clinical pattern of 545 consecutive young diabetic patients with age at onset below 30 years attending a diabetes centre in Southern India. Three hundred and fourteen patients (57.7%) were classified as having non-insulin-dependent diabetes of the young (NIDDY), 119 (22%) as insulin-dependent diabetes (IDDM) and 28 (5%) as malnutrition-related diabetes (MRDM); 4% fibrocalculous pancreatic diabetes and 1% protein-deficient pancreatic diabetes. The remaining 84 patients could not be classified into any of the above categories. A positive family history of diabetes was more common in NIDDY compared to the other groups (P less than 0.001). While 40.3% of patients with IDDM had age at onset below 15 years, the other types of diabetes were rarely seen in patients younger than this. Body mass index (BMI) did not reliably indicate the MRDM forms of diabetes as 70% of patients with IDDM also had a BMI of less than 18, one of the criteria recommended for the diagnosis of MRDM. C-peptide levels in MRDM were intermediate between the IDDM and NIDDY groups. Microvascular complications were present in all the groups of young diabetics. The frequency was higher in NIDDY patients who also had a longer duration of diabetes. There was an increasing prevalence of complications with increasing duration of diabetes. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Glycated Hemoglobin; Humans; India; Male; Protein-Energy Malnutrition | 1988 |
Factors associated with early remission of type I diabetes in children treated with cyclosporine.
To improve criteria for entry into future trials of immunosuppression, we enrolled 40 children with recent-onset Type I insulin-dependent diabetes in a pilot trial of cyclosporine. Twenty-seven patients were able to discontinue insulin therapy 48 +/- 5 days after the start of immunosuppression. At four months, their fasting and postprandial blood glucose concentrations averaged 110 and 160 mg per deciliter (6.1 and 8.9 mmol per liter) with a mean hemoglobin A1c level of 6.15 percent. Seventy-five percent of these patients with early remission still did not need insulin at 12 months, and their glycemic control was similar to that at 4 months. The major differences between the 27 patients with remission and the 13 without remission were the duration of symptoms before diagnosis (26.8 vs. 48.0 days, P less than 0.01), the degree of weight loss (3.2 vs. 10 percent of body weight, P less than 0.001), the initial hemoglobin A1c level (10.7 vs. 13.2 percent, P less than 0.001), and the frequency of ketoacidosis (11 vs. 61.5 percent, P less than 0.001). The lesser degree of weight loss was the strongest independent predictor of remission. The response of C-peptide to intravenous glucagon (0.50 vs. 0.17 pmol per milliliter, P less than 0.05) was also an independent predictor. No differences were observed between the two groups of patients in age, sex, HLA phenotype, autoantibodies to insulin or islet-cell antigens, or doses or trough levels of cyclosporine. Only minimal manifestations of toxicity were detected over the period of observation. We conclude that early treatment with cyclosporine in children with recent-onset Type I diabetes can induce remission from insulin dependence, with half the patients not requiring insulin after a full year. Topics: Adolescent; Age Factors; Blood Glucose; Body Weight; C-Peptide; Child; Cyclosporins; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Insulin; Male; Pilot Projects; Remission Induction; Sex Factors; Time Factors | 1988 |
Heterogeneity of serum basal C peptide levels amongst Arab patients with diabetes mellitus.
Thirty-four Arab patients with history of diabetes mellitus but without history of ketoacidosis (Group 2), and 16 Arab patients with history of diabetes mellitus and ketoacidosis (Group 1) were studied. They were compared with 15 healthy control subjects and were further broken down according to sex and type of therapy. Fasting serum C-peptide, glucose and glycosylated haemoglobin levels were measured in all subjects. C-peptide levels in Group 2 were higher (t = 2.95) and exhibited greater heterogeneity (Variance ratio 3.60, p less than 0.005) than those in Group 1. Female subjects in Group 2 were more obese than male subjects in the same group, and exhibited greater heterogeneity of their C-peptide levels (Variance ratio 9.47, p less than 0.001). Although male patients in Group 2 on insulin therapy were older than male subjects on diet or oral hypoglycemic agents (t = 3.52, p less than 0.01), female subjects on insulin therapy were younger than those on diet or oral hypoglycemic agents (t = 2.05, p less than 0.05). Furthermore female patients on insulin therapy had lower serum glycosylated haemoglobin levels than female subjects on oral hypoglycemic agents (t = 2.05, p less than 0.05) but male patients on insulin therapy had higher serum glycosylated haemoglobin than those on oral hypoglycemic agents. These data suggest the earlier tendency of physicians to prescribe insulin in women of child bearing age but suggest that earlier prescribing habits of insulin may improve diabetic control.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Female; Glycated Hemoglobin; Humans; Kuwait; Male; Sex Factors | 1988 |
[Effect of biostator control on levels of contra-insulin hormones].
A 24 hour biostator control was carried out on 30 patients with insulin dependent diabetes, mean age 34 years (16-61 years) and mean duration of the disease 7 years (1-33 years). All patients had normal body mass (+/- 10% according to Broka's formula). The plasma levels of glucagon, growth hormone, cortisol and C-peptide were determined at the beginning and at the end of the biostator control. With the decrease of glycemia (from 12.71 +/- 4.3 to 5.75 +/- 1.5 mmol/l, p less than 0.001) only the cortisol level fell reliably (p less than 0.001), the growth hormone and glucagon levels fell statistically insignificantly. There is no reliable correlation between the contra-insulin hormones studied and the glycemia level. Topics: Adolescent; Adult; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Glucagon; Growth Hormone; Humans; Hydrocortisone; Insulin Antagonists; Insulin Infusion Systems; Middle Aged | 1988 |
Day-to-day variation in glycemic control in type I and type II diabetes mellitus.
In an attempt to assess day-to-day variation in glycemic control, 12 type I and 12 type II diabetic subjects were hospitalized and had plasma glucose sampled frequently on two consecutive days, during which medication, diet, and physical activity were all held constant. In type I subjects, there was no significant day-to-day correlation in overall mean plasma glucose, mean preprandial plasma glucose, mean postprandial plasma glucose, or urinary glucose excretion. In contrast, these measures were all highly correlated in type II subjects. The data suggest that individuals with type I diabetes may not be able to achieve good glycemic control simply by taking the same dose or doses of insulin each day while rigorously attempting to control diet and exercise. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glycosuria; Humans; Inpatients | 1988 |
Increased prevalence of neurologic complications among insulin dependent diabetic patients of Algerian origin.
This study was undertaken to ascertain a clinical impression that the prevalence of complications is higher in insulin-dependent Algerian diabetics than in their European counterparts. Forty-one Algerian patients under regular follow-up for 2 years or more were closely matched to 41 French insulin dependent diabetics with regard to sex (34M/7F) and duration of disease (10.5 +/- 1 year; range 2 -32 years). Insulin dose, number of injections, arterial blood pressure, glycemia, glycosylated haemoglobin, cholesterolemia and triglyceridemia were similar in the two groups. The age at the time of diagnosis of diabetes was higher in the Algerian group (28.7 +/- 1.9 vs 21.4 +/- 1.7) as was the number of smokers (23/41 vs 12/41). No difference was noted between the two groups with respect to the prevalence of retinopathy (absent, simple, proliferative): 25, 12, and 4 vs 29, 9, and 3 or nephropathy (absent, incipiens, patent): 30, 6, 5 for the Algerians and 35, 3, 2 for the French. This suggest that long term metabolic control was relatively identical in the two groups. The incidence of neuropathy rated as absent, moderate (abolished reflexes, impaired pallesthesia, cardiac neuropathy) or severe was significantly higher in the Algerians (13, 16 and 12) as compared to the French (28, 10 and 3) p less than 0.01. Severe neuropathy in the Algerian group was often multiple (8/12), serious and early. The only difference between the neuropathic and non-neuropathic Algerian subgroups was the duration of disease (13.2 +/- 2.2 vs 7.3 +/- 0.01; p less than 0.01). Since there were apparently no acquired nutritional factors, an ethnic predisposition of Algerians to develop neuropathy seems likely.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Algeria; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Female; Follow-Up Studies; France; Humans; Male; Risk Factors | 1988 |
[Study of the "dawn phenomenon" using an artificial endocrine pancreas].
30 insulin-dependent, C-peptide negative diabetic patients were examined with the help of biostator. The mean age of the patients was 29 years, the mean duration of the diabetes was 7 years and the mean index of body mas was 22. For the period from 0 to 8 o'clock in the morning the blood sugar level and the speed of the insulin infusion in order to maintain euglycemic level were examined at 1/2 hour intervals. The mean blood sugar level for the period 5-8 o'clock (5.71 +/- 0.31 mmol/l) was reliably higher (p less than 0.05) than that for the period 0-5 o'clock (5.4 +/- 0.18 mmol/l). The speed of the insulin infusion for the period 5-8 o'clock (0.52 +/- 0.09 IU/kg/min) was also reliably higher (p less than 0.02) than that for the period 0-5 o'clock (0.4 +/- 0.06 IU/kg/min). These two indices were correlated with the somatotropic hormone and hydrocortisone levels at 2 and 8 o'clock. The possible pathogenetic mechanisms of this "morning phenomenon" in diabetes is discussed. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Insulin Infusion Systems; Male; Time Factors | 1988 |
Evidence of IgG autoantibodies against human proinsulin in patients with IDDM before insulin treatment.
IgG proinsulin autoantibodies (IgG-PAAs) have been found in a fraction of sera from patients with newly diagnosed insulin-dependent diabetes mellitus (IDDM) before onset of insulin treatment. Only sera lacking insulin antibodies have been analyzed, to avoid interference. Competitive inhibition studies provide specificity for human proinsulin but not for insulin. IgG-PAAs largely cross-react with human C-peptide. Precursors of insulin thus are involved in the immune process of IDDM. Topics: Adolescent; Adult; Antibody Specificity; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin G; Insulin; Male; Proinsulin | 1988 |
Correlation between minimal secretory capacity of pancreatic beta-cells and stability of diabetic control.
The significance of the minimal secretory capacity of pancreatic beta-cells for the stability of the plasma glucose level was studied in 20 patients with insulin-dependent diabetes mellitus. Changes in plasma concentrations of major counterregulatory hormones in response to hypoglycemia were also investigated in these patients to clarify their contribution to diabetic brittleness. beta-Cell function was evaluated on the basis of elevation of plasma C-peptide immunoreactivity (CPR) during the intravenous glucagon test with a highly sensitive assay for plasma CPR that could detect as little as 0.03 ng/ml. After stimulation with glucagon, a significant increase in plasma CPR was observed in 10 of the patients whose beta-cell function had been evaluated as completely depleted by a conventional assay for plasma CPR. A clear inverse correlation was found between the secretory capacity of pancreatic beta-cells measured in this way and the degree of glycemic instability (r = -.74, P less than .01). Infusion of insulin at a rate of 0.15 U.kg-1.h-1 for 60 min caused a continuous decrease in the plasma glucose level, resulting in neuroglycopenia in 7 of the 10 CPR nonresponders but only 2 of the CPR responders. During insulin-induced hypoglycemia, plasma glucagon immunoreactivity did not increase in the CPR nonresponders but increased significantly in the CPR responders. A positive correlation was found between the minimal residual beta-cell capacity and the responsiveness of alpha-cells to hypoglycemia (r = .65, P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Growth Hormone; Humans; Hydrocortisone; Insulin; Islets of Langerhans; Kinetics; Male; Middle Aged; Norepinephrine | 1988 |
Organ-specific autoimmunity and HLA-DR antigens as markers for beta-cell destruction in patients with type II diabetes.
Islet cell antibodies (ICAs), thyrogastric antibodies, and HLA-DR antigens were determined in 204 patients with type II (non-insulin-dependent) diabetes controlled with diet and/or oral hypoglycemic agents (NIR) and in 108 age-matched patients who required insulin to control their hyperglycemia (IR). beta-Cell function measured as C-peptide response to glucagon was evaluated in relation to the presence of ICAs and HLA-DR antigens. The IR patients differed from the NIR patients with respect to higher frequency of ICAs (P less than .001), thyroid antibodies (P less than .02), and the HLA antigen DR4 (P less than .02). The highest frequency of ICAs and thyroid antibodies was observed in female insulin-treated subjects (51.2 and 46.4%). Patients who were heterozygous for HLA-DR3/DR4 showed significantly higher frequency of ICAs (P less than .01) and complement-fixing ICAs (P less than .001) than patients without the heterozygous form DR3/DR4. Neither the presence of ICA alone nor DR3/DR4 alone was associated with a significant impairment of beta-cell function. However, when both ICA and DR3/DR4 were present in a diabetic individual, beta-cell function was markedly impaired (P less than .001), suggesting that both genetic and autoimmune factors are necessary to facilitate the process leading to beta-cell destruction of the patients. Our findings suggest that type II diabetes is a heterogeneous disorder including at least two major subgroups, which can be further characterized by HLA-DR antigens and organ-specific antibodies. Topics: Autoantibodies; Autoimmune Diseases; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Heterozygote; HLA-D Antigens; HLA-DR Antigens; HLA-DR3 Antigen; HLA-DR4 Antigen; Humans; Insulin; Islets of Langerhans; Male; Parietal Cells, Gastric; Thyroid Gland | 1988 |
Relationship of islet cell and islet cell surface antibodies to the presentation and early course of IDDM in childhood.
Islet cell (ICA) and islet cell surface (ICSA) antibodies were measured in 30 children (aged 6-17.7 years) with newly diagnosed insulin-dependent diabetes mellitus (IDDM) to determine the relationship of antibody positivity/negativity to a variety of factors both at presentation (e.g., age, severity of onset, residual insulin secretion, insulin autoantibodies) and during the first year thereafter (HbA1c, insulin antibody binding, residual insulin secretion). At diagnosis, 10 of 30 were ICA (+) and 13 ICSA (+): no differences were found between ICA (+) and (-) subjects at onset; however ICSA (+) children had a lower bicarbonate concentration than those (-) for ICSA (P less than 0.01). During the first year after diagnosis the only significant finding was that in ICA (+) patients insulin dose (units/kg) was lower at both 6 and 12 months (mean +/- SD 0.55 +/- 0.14 and 0.67 +/- 0.12 U/kg, respectively) than ICA (-)'s (0.70 +/- 0.22 and 0.96 +/- 0.38, respectively, both P less than 0.05). Those children positive for both ICA and ICSA did not differ in any way at onset or during the subsequent 12 months from those negative for both antibodies. These results suggest that, except for minor differences, the presentation and course during the first year after diagnosis of IDDM do not differ in those children positive or negative for either or both ICA and ICSA. Topics: Adolescent; Aging; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Fluorescent Antibody Technique; Humans; Islets of Langerhans; Male | 1988 |
The adjustment of diet and insulin dose during long-term endurance exercise in type 1 (insulin-dependent) diabetic men.
We examined in 2 consecutive years the effect of a 75-km (greater than 7 h) cross country skiing on dietary and insulin requirements and glycaemic control in 9 Type 1 (insulin-dependent) diabetic patients. In the first year, the patients were hyperglycaemic (20.9 +/- 1.8 mmol/l) before the race due to excessive carbohydrate loading (65 g) and reduction (by 58%) of short-acting insulin for breakfast. In the second year, breakfast included less carbohydrate (40 g) and more protein, and the morning short-acting insulin was reduced by 35%. With this adjustment of therapy the pre-exercise hyperglycaemia was less (p less than 0.05). The morning intermediate-acting insulin was reduced by 28 and 38% in consecutive years. During both races carbohydrate intake approximated 40 g/h, and blood glucose was maintained at near normal levels after 33 km of skiing. Hypoglycaemia did not occur during exercise, but one patient had symptomatic hypoglycaemia after finishing the second race. The day after exercise insulin sensitivity was increased in all four patients studied. Insulin treated patients can perform strenuous long-term exercise and maintain near normoglycaemia with a proper adjustment of therapy. Augmented insulin sensitivity may contribute to post-exercise hypoglycaemia. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diet, Diabetic; Dietary Carbohydrates; Dietary Proteins; Glycated Hemoglobin; Humans; Injections, Intramuscular; Insulin; Male; Physical Endurance; Physical Exertion; Skiing | 1988 |
Increased proinsulin levels as an early indicator of B-cell dysfunction in non-diabetic twins of type 1 (insulin-dependent) diabetic patients.
Glucose tolerance and insulin secretion were studied in two groups of non-diabetic identical twins of recently-diagnosed Type 1 (insulin-dependent) diabetic patients: (1) a group of 5 twins with islet cell antibodies, and (2) a group of 6 twins without. Despite similar fasting glucose, insulin and C-peptide concentrations both groups of twins had significantly higher fasting proinsulin concentrations than the control group (p less than 0.05). The twins with complement-fixing islet cell antibodies had reduced glucose tolerance and clearance, whilst the twins without islet cell antibodies did not. Neither group of twins showed any abnormality in insulin, C-peptide or proinsulin response to oral or intravenous glucose. We conclude that increased fasting proinsulin levels precede abnormalities of insulin secretion, and are an early indication of minor B-cell damage in these twins irrespective of their risk of developing diabetes. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Prognosis; Proinsulin; Reference Values; Risk Factors; Twins; Twins, Monozygotic | 1988 |
Gastric inhibitory polypeptide in newly diagnosed ketotic type I (insulin-dependent) diabetics.
Plasma concentrations of 5,000 daltons (5 kDa) immunoreactive gastric inhibitory polypeptide (IR-GIP) were measured before and up to 16 hours after the start of low-dose insulin treatment in newly diagnosed ketotic type I (insulin-dependent) diabetics. Nine patients were non-fasting. Before insulin treatment mean IR-GIP was 31 +/- 6 pmol/l (range 9-65 pmol/l). Four patients had IR-GIP concentrations in the normal fasting range (10-25 pmol/l), and nine patients had concentrations below 35 pmol/l. The remaining patients had IR-GIP concentrations in the normal postprandial range. A meal eaten after the start of insulin treatment caused an increase in IR-GIP in all patients. All patients had beta-cell function as estimated by plasma C-peptide. Individual changes in C-peptide were significantly correlated to changes in blood glucose both after the meal (r = 0.80, p less than 0.01) and during insulin treatment (r = 0.85 +/- 0.04). No correlation could be found between IR-GIP and blood glucose, C-peptide or insulin concentrations. Newly diagnosed ketotic type I diabetics have IR-GIP concentrations within the normal postprandial level. Hypoinsulinaemia, hyperglycaemia, and hyperketonaemia do not by themselves increase 5 kDa IR-GIP markedly above normal fasting levels. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Gastric Inhibitory Polypeptide; Humans; Insulin; Male | 1988 |
Influence of circulating epinephrine on absorption of subcutaneously injected insulin.
Effects of epinephrine (Epi) infusion on the absorption of subcutaneously injected 125I-labeled soluble human insulin (10 U) from the thigh or the abdomen were studied in 16 healthy subjects and from the thigh in 10 insulin-dependent diabetic (IDDM) patients. Epi was infused at 0.3 (high dose) or 0.1 (low dose; healthy subjects) nmol.kg-1.min-1 i.v., resulting in arterial plasma Epi levels of approximately 6 and 2 nM, respectively. Saline was infused on a control day. Insulin absorption was measured as disappearance of radioactivity from the injection site and as appearance of plasma immunoreactive insulin (IRI). Adipose tissue blood flow was measured with the 133Xe clearance technique. First-order disappearance rate constants of 125I from the thigh depot decreased approximately 40-50% during the high dose of Epi compared with control (P less than .001). The corresponding decrease from the abdominal depot was approximately 40% (P less than .001), whereas no significant change was found during the low Epi dose. IRI fell compared with control in all groups at the high Epi dose. The Epi-induced depression of insulin absorption occurred despite unaltered or even slightly increased subcutaneous blood flow. The results indicate that circulating Epi at levels seen during moderate physical stress depresses the absorption of soluble insulin from subcutaneous injection sites to an extent that might be important for glycemic control in IDDM patients. Furthermore, dissociation is found between changes in insulin absorption and subcutaneous blood flow during Epi infusion, suggesting that factors other than blood flow may also influence the absorption of subcutaneously injected insulin. Topics: Absorption; Adipose Tissue; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Humans; Injections, Subcutaneous; Insulin; Iodine Radioisotopes; Male; Radioimmunoassay; Regional Blood Flow; Stress, Physiological | 1988 |
Prospective study of predictors of beta-cell survival in type I diabetes.
We conducted a prospective study to describe the course of the pancreatic beta-cell function from the time of clinical diagnosis of insulin-dependent (type I) diabetes to determine whether DR type, presence of islet cell antibodies (ICA), presence of insulin antibodies (IA), age at onset, and sex could help in the prediction of residual endogenous insulin secretion. A cohort of 68 children was followed for 18 mo after diagnosis of type I diabetes. The outcome variables selected for analysis were 1) serum C-peptide peak concentration after a Sustacal meal, 2) time of disappearance of the serum C-peptide response, and 3) time after diagnosis at which the maximal serum C-peptide response was observed. After institution of insulin therapy, serum C-peptide peak concentrations rose temporarily for 1-6 mo and declined thereafter. Multivariate analysis of the data showed that DR type (P = .2488) and presence of IA (P = .1604) had no effect on serum C-peptide over time, but sex (P = .0146), age at onset (P = .0002), and presence of ICA (P = .0147) significantly contributed to the variation of serum C-peptide over time. Furthermore, age at onset, presence of ICA, and sex were also the only significant predictors of the time of disappearance of the beta-cell function. The relative risks of beta-cell-function disappearance were 0.87 (P = .0015), 9.43 (P = .0181), and 2.25 (P = .0468), respectively. In conclusion, there are distinct variations in the natural course of the beta-cell function in type I diabetes. beta-Cell-function survival is significantly shortened the younger the subject is at disease onset, if ICA are present at diagnosis, and if the subject is male. Topics: Adolescent; Age Factors; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Prospective Studies; Risk Factors; Sex Factors | 1988 |
Hypoglycaemia in childhood diabetes. I. Clinical signs and hormonal counterregulation.
Hypoglycaemia (blood glucose 1.3-2.5 mmol/l) was induced in twenty-eight diabetic children by reduction of their morning meal. Fatigue and pallor were the most common signs of hypoglycaemia. Compared to findings during normoglycaemia, plasma concentrations of adrenalin, noradrenalin and cortisol were significantly higher at glucose nadir. Plasma glucagon concentration at glucose nadir was correlated to the fasting C-peptide concentration and inversely to the duration of diabetes. Children who lacked C-peptide also lacked glucagon response to hypoglycaemia. The parents' opinion of the need to give carbohydrates corresponded to the blood glucose level. The presence of adrenergic signs correlated to the plasma adrenalin and the neuroglucopenic signs to blood glucose. The lowest glucose level correlated inversely to the concentration of free insulin. When facilities for glucose infusion are lacking, a rational step in treating the unconscious hypoglycaemic child seems to be the injection of glucagon, considering the blunted or absent glucagon secretion. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Epinephrine; Female; Humans; Hydrocortisone; Hypoglycemia; Insulin; Male; Norepinephrine | 1988 |
Cyclosporine, in combination with other drugs, studied in insulin-dependent diabetes therapy.
Topics: Bromocriptine; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Humans | 1988 |
High-dose gammaglobulin therapy in six children with newly diagnosed insulin-dependent diabetes mellitus.
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; gamma-Globulins; Humans; Insulin; Male | 1987 |
The effects of hyperglycaemia on isotopic measurement of glucose utilisation using [2(3)H], [3(3)H] and [6(14)C] glucose in patients with type 1 (insulin-dependent) diabetes mellitus.
To determine whether hyperglycaemia alters the accuracy with which [2(3)H] and [3(3)H]glucose reflect glucose turnover measured with [6(14)C]glucose in patients with Type 1 (insulin-dependent) diabetes mellitus, glucose utilisation rates were measured during a simultaneous infusion of [2(3)H], [3(3)H] and [6(14)C]glucose after maintenance of normoglycaemia overnight and when glucose concentrations were clamped at 5.3, 7.5 and 9.7 mmol/l while insulin and glucagon concentrations were held constant. Glucose utilisation rates determined with all three isotopes were comparable in the diabetic patients at all glucose concentrations studied. On the other hand, glucose utilisation rates in nondiabetic subjects determined with [6(14)C]glucose were greater (p less than 0.01) than those determined with [3(3)H]glucose and lower (p less than 0.04) than those determined with [2(3)H]glucose during the 5.3, 7.5 and 9.7 mmol/l clamps. Nevertheless, glucose utilisation rates in the diabetic patients were lower (p less than 0.05) than those in the nondiabetic subjects for each glucose isotope. We conclude that hyperglycaemia does not alter the pattern of metabolism of [2(3)H] or [3(3)H]glucose in patients with Type 1 (insulin-dependent) diabetes mellitus. Topics: Adult; Blood Glucose; C-Peptide; Carbon Radioisotopes; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose; Growth Hormone; Humans; Hyperglycemia; Insulin; Kinetics; Male; Radioisotope Dilution Technique; Reference Values; Somatostatin; Tritium | 1987 |
Glucose control after simultaneous segmental pancreas and kidney transplantation.
Topics: Antibodies, Monoclonal; Blood Glucose; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Glucose Tolerance Test; Humans; Insulin; Kidney Transplantation; Pancreas Transplantation | 1987 |
Effect of glyburide on glycemic control, insulin requirement, and glucose metabolism in insulin-treated diabetic patients.
Glycemic control and glucose metabolism were examined in 5 patients with insulin-dependent diabetes mellitus (IDDM) and 8 insulin-treated non-insulin-dependent diabetes mellitus (NIDDM) patients before and after 2 mo of therapy with glyburide (20 mg/day). Glycemic control was assessed by daily insulin requirement, 24-h plasma glucose profile, glucosuria, and glycosylated hemoglobin. Insulin secretion was evaluated by glucagon stimulation of C-peptide secretion, and insulin sensitivity was determined by a two-step euglycemic insulin clamp (1 and 10 mU X kg-1. X min-1) performed with indirect calorimetry and [3-3H]glucose. In the IDDM patients, the addition of glyburide produced no change in daily insulin dose (54 +/- 8 vs. 53 +/- 7 U/day), mean 24-h glucose level (177 +/- 20 vs. 174 +/- 29 mg/dl), glucosuria (20 +/- 6 vs. 35 +/- 12 g/day) or glycosylated hemoglobin (10.1 +/- 1.0 vs. 9.5 +/- 0.7%). Furthermore, there was no improvement in basal hepatic glucose production (2.1 +/- 0.2 vs. 2.4 +/- 0.1 mg X kg-1 X min-1), suppression of hepatic glucose production by low- and high-dose insulin infusion, or in any measure of total, oxidative, or nonoxidative glucose metabolism in the basal state or during insulin infusion. C-peptide levels were undetectable (less than 0.01 pmol/ml) in the basal state and after glucagon infusion and remained undetectable after glyburide therapy. In contrast to the IDDM patients, the insulin-treated NIDDM subjects exhibited significant reductions in daily insulin requirement (72 +/- 6 vs. 58 +/- 9 U/day), mean 24-h plasma glucose concentration (153 +/- 10 vs. 131 +/- 5 mg/dl), glucosuria (14 +/- 5 vs. 4 +/- 1 g/day), and glycosylated hemoglobin (10.3 +/- 0.7 vs. 8.0 +/- 0.4%) after glyburide treatment (all P less than or equal to .05). However, there was no change in basal hepatic glucose production (1.7 +/- 0.1 vs. 1.7 +/- 0.1 mg X kg-1 X min-1), suppression of hepatic glucose production by insulin, or insulin sensitivity during the two-step insulin-clamp study. Both basal (0.14 +/- 0.05 vs. 0.32 +/- 0.05 pmol/ml, P less than .05) and glucagon-stimulated (0.24 +/- 0.07 vs. 0.44 +/- 0.09 pmol/ml) C-peptide levels rose after 2 mo of glyburide therapy and both were correlated with the decrease in insulin requirement (basal: r = .65, P = .08; glucagon stimulated: r = .93, P less than .001).(ABSTRACT TRUNCATED AT 400 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glyburide; Humans; Insulin; Liver; Male; Time Factors | 1987 |
Increased incidence of true type I diabetes acquired during pregnancy.
A longitudinal study was carried out of all patients with newly acquired insulin dependent diabetes during pregnancy (as distinct from non-insulin-dependent gestational diabetes) seen at the Copenhagen Centre for Diabetes and Pregnancy during 1966 to 1980. The series comprised 63 patients with a mean age of 27 (SEM 1) years. At diagnosis the mean fasting blood glucose concentration was 15.6 (1.3) mmol/l and mean maximal insulin dose 49 (3) IU/day. At a prospective follow up examination a mean of 8 (SEM 1) years after diagnosis 46 of 60 patients (77%) were being treated with insulin (35 (2) IU/day) and had a very low mean stimulated plasma C peptide value (0.12 (0.02) nmol/l) suggesting absent or nearly absent beta cell function. The remaining 14 patients (23%), not currently receiving insulin, appeared to be severely glucose intolerant, having a mean fasting blood glucose concentration of 13.4 (1.2) mmol/l. Thus most of these patients developing insulin dependent diabetes during pregnancy had true type I disease. Compared with the age specific incidence of type I diabetes in the background population of women the incidence was at least 70% higher in pregnant than non-pregnant women (p less than 0.001; chi 2 = 11.6; f = 1). This increased incidence occurred in the third trimester when the risk of developing type I diabetes was 3.8 times that of non-pregnant women (p less than 0.000001; chi 2 = 35.6; f = 1). Finally, the risk of developing insulin dependent diabetes during pregnancy was lower when conception occurred in the winter (p less than 0.05; chi 2 = 4.18; f = 1). Topics: Adult; Blood Glucose; C-Peptide; Denmark; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Longitudinal Studies; Pregnancy; Pregnancy in Diabetics; Prospective Studies; Seasons | 1987 |
Diabetogenic effect of cyclosporin.
A young woman given a renal allograft for polycystic kidney disease developed insulin dependent diabetes mellitus 25 days after transplantation. There was no family history of diabetes, plasma glucose concentrations had been normal at presentation and on five subsequent occasions, and at no time were islet cell antibodies detectable. Plasma C peptide concentrations, however, were greatly suppressed after transplantation and remained so for up to six months. The immunosuppressive regimen had included cyclosporin A, which had been difficult to regulate and caused definite signs of toxicity in the patient. By virtue of its reported toxicity for beta cells and the reversal of the diabetes several months after the dose was reduced cyclosporin was incriminated as the probable causative agent. Dose related beta cell toxicity of cyclosporin A may be a risk in recipients of this drug and warrants careful monitoring of drug and glucose concentrations. Topics: Adolescent; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Female; Humans; Kidney Transplantation; Polycystic Kidney Diseases | 1987 |
Blunted prolactin response to metoclopramide in insulin-dependent diabetic patients with secondary amenorrhoea.
In order to investigate the dopaminergic activity in diabetic women with secondary amenorrhoea we studied the response of prolactin to a dopamine receptor antagonist metoclopramide (MTC - 10 mg i.v.) in three groups of women: 5 insulin-dependent diabetic women with secondary amenorrhoea, 5 insulin-dependent diabetics with normal menstrual cycles and 6 non-diabetic women with regular cycles. Patients with diabetes and secondary amenorrhoea had significantly lower basal LH levels (P less than 0.001) and FSH levels (P less than 0.005) than normally cycling diabetic women. Basal and metoclopramide stimulated prolactin levels were lower in diabetic women with secondary amenorrhoea compared to normally cycling diabetics and control subjects. Evaluation of C-peptide levels in peripheral blood revealed that all amenorrheic diabetics had no endogenous beta cell function while diabetic women with normal cycles (except 1 patient) had preserved residual pancreatic beta cell secretion. Topics: Adult; Amenorrhea; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Metoclopramide; Prolactin | 1987 |
The classification of diabetes mellitus in children and adolescents.
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; HLA Antigens; Humans; Remission, Spontaneous | 1987 |
Results of cultured fetal pancreatic islet transplantation in juvenile diabetic patients.
Topics: Adult; C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Female; Fetus; Humans; Insulin; Islets of Langerhans Transplantation; Liver; Male; Middle Aged; Transplantation, Heterotopic | 1987 |
Twenty-four hour urinary C-peptide and fasting plasma C-peptide as indicators of metabolic control in 83 insulin dependent diabetic patients.
Topics: Adolescent; Adult; Aged; C-Peptide; Child; Diabetes Mellitus, Type 1; Fasting; Female; Glycated Hemoglobin; Humans; Insulin; Male; Middle Aged | 1987 |
Preservation of human pancreatic allografts in cold storage for six to 24 hours.
Topics: C-Peptide; Cold Temperature; Diabetes Mellitus, Type 1; Follow-Up Studies; Glucose Tolerance Test; Graft Survival; Humans; Immunosuppression Therapy; Organ Preservation; Pancreas Transplantation; Time Factors; Transplantation, Homologous | 1987 |
Effect of human fetal pancreas transplantation on secretion of C-peptide and glucose tolerance in type I diabetics.
Topics: Arginine; C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Fetus; Glucose; Glucose Tolerance Test; Humans; Kidney Transplantation; Pancreas Transplantation | 1987 |
Maternal residual beta-cell function and the outcome of diabetic pregnancy.
Preservation of own insulin production (residual pancreatic beta-cell function) has been shown to have a beneficial effect on glycemic control in insulin-dependent diabetic subjects, and its total lack has been suggested to be an independent risk factor during diabetic pregnancy. We studied the influence of residual beta-cell activity on the glucose control and the outcome of pregnancy in 29 diabetic women by sequentially measuring gestational postprandial plasma C-peptide (CPR) levels, diurnal blood glucose curves and blood glycosylated hemoglobin (Hb A1c) and by analyzing the morbidity and mortality of the offsprings. The 9 diabetics with moderate own insulin secretion (CPR levels over 1.0 microgram/l, White classes B and C, later referred to as group I) had significantly better glucose control than the remaining 20 subjects with lower CPR values (White classes C, D and NF, later referred to as group II) (figure 1, table I). There were two intrauterine deaths, both in group II. These deaths (one caused by multiple congenital contracture syndrome and the other by severe intrauterine growth retardation without any evident cause) could not be straightly connected with diabetes. Respiratory distress syndrome was seen in group II only. There was no other significant difference in the neonatal morbidity between the two groups (table II). All mothers of RDS infants were in White class NF where the birthweight was also smaller than in classes B and C. These were the only differences in neonatal morbidity between the White classes (table III). In conclusion, moderate residual beta-cell function seemed to be clinically important in maintaining strict glucose control during gestation.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Infant, Newborn; Insulin; Islets of Langerhans; Pregnancy; Pregnancy in Diabetics; Risk | 1987 |
Residual insulin production, glycaemic control and prevalence of microvascular lesions and polyneuropathy in long-term type 1 (insulin-dependent) diabetes mellitus.
The aim of the present study was to evaluate the role of residual insulin production in long-term Type 1 (insulin-dependent) diabetes mellitus. Ninety-seven patients with a disease duration of 9-16 years and onset before the age of 30 years were studied. C-peptide excretion in 24-h urine samples was measured as an indicator of residual insulin production. Thirty-five patients (36%) excreted C-peptide (greater than or equal to 0.2 nmol); as many as possible of them were carefully matched with a non-excretor patient with regard to age at onset of diabetes and disease duration. Twenty-nine pairs were obtained, and 22 of them agreed to participate in further investigations of glycaemic control and microangiopathic lesions. The patients who excreted C-peptide had significantly lower HbA1c than the non-excretor group, 6.9 +/- 0.3% vs 7.9 +/- 0.3%, (p less than 0.025). Moderate-to-advanced background retinopathy was found in 2 patients in the excretor group and in 7 patients in the non-excretor group. Microalbuminuria [ratio of albumin: creatinine (mg/l:mmol/l) greater than or equal to 5] was found in 1 and in 5 patients, respectively, while proteinuria [ratio of protein: creatinine (mg/l:mmol/l X 10) greater than or equal to 136] was found in 0 and in 4 patients, respectively. Microalbuminuria and/or proteinuria was found in 7 of the non-excretor group as compared to 1 in the excretor group (p = 0.046).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Albuminuria; beta 2-Microglobulin; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Male; Proteinuria | 1987 |
5-year follow-up study of C-peptide secretion in newly diagnosed type I diabetics: relations to HLA-phenotype, insulin requirement and metabolic control.
50 HLA-typed insulin-dependent diabetics were studied at the time of diabetes onset and after 1, 2, 3 and 5 years with regard to C-peptide secretion after combined stimulation with glucose and glucagon, insulin requirement and glycaemic control index. The mean decrease of the residual B-cell reserve was observed within two years. C-peptide secretion was correlated with better metabolic control and lower insulin requirement after more than one year of diabetes duration, but had no influence on this at the time of diabetes onset. The C-peptide response sometimes varied between non response and high response in one individual from one investigation to the next. There was no prognostic value of C-peptide secretion at diabetes onset for the further development of B-cell function. We found a significantly longer persistence of B-cell function in patients who were older and in those with mild symptoms at diabetes onset. The presence of HLA B8, DR3 antigens was correlated with severe ketoacidosis at manifestation and a more pronounced destruction of B-cell function. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; HLA Antigens; Humans; Insulin; Male; Phenotype; Prognosis | 1987 |
Metabolic control and B cell function in patients with insulin-dependent diabetes mellitus secondary to chronic pancreatitis.
Among 88 unselected patients with chronic pancreatitis 35% (95% confidence limits 25 to 46) had insulin-dependent diabetes, 31% (21% to 41%) had non-insulin-dependent diabetes or impaired glucose tolerance (by intravenous glucose tolerance test), and 34% (24% to 45%) had normal glucose tolerance. B cell function measured by C-peptide concentration after 1 mg glucagon IV correlated with the pancreatic enzyme secretion (meal stimulated duodenal lipase content). B cell function was preserved to a greater extent (P less than .01), and glycosylated hemoglobin and fasting level of glucose were lower (P less than .01 to .05) in the 31 patients with pancreatogenic diabetes than than in 35 otherwise comparable patients with type I (insulin-dependent) diabetes, yet daily insulin dose was similar in the two groups. Glucagon stimulated C-peptide was inversely correlated to glycosylated hemoglobin in insulin-dependent patients with pancreatogenic diabetes and in type I diabetes. Since body mass indices were identical in the two groups, better glucoregulation was not due to reduced food intake or malabsorption in pancreatogenic diabetes. Rather residual B cell function and/or different secretion of other pancreatic hormones in pancreatogenic diabetes may account for different metabolic control in type I IDDM compared with insulin-dependent pancreatogenic diabetes. Topics: Adult; C-Peptide; Chronic Disease; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Islets of Langerhans; Male; Middle Aged; Pancreatitis | 1987 |
[Post-initial remission of diabetes in childhood].
Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Humans; Immunoglobulin A; Insulin; Remission Induction; Time Factors | 1987 |
A follow-up study of cell-mediated cytotoxicity and beta cell function in type I diabetes.
In 20 patients with a newly diagnosed type I diabetes mellitus a cytotoxic effect of blood lymphocytes against beta cells of the pancreas of neonatal rats could be demonstrated. This effect remained nearly unchanged during the first 12 months of control. During the course up to 18 months, the cytotoxicity decreased significantly. After stimulation with glucose and glucagon, a C-peptide secretion was demonstrated in all patients during the first 12 months but it decreased thereafter. The follow-up study showed cell-mediated immune reactions against beta cells in type I diabetics as long as the existence of beta cells can be assumed on the basis of functional tests. Thus the immune process seems to depend on the presence of the specific antigen. Topics: Adolescent; Adult; Animals; C-Peptide; Child; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Islets of Langerhans; Middle Aged; Rats; Rats, Inbred Strains; T-Lymphocytes, Cytotoxic | 1987 |
Factors affecting and patterns of residual insulin secretion during the first year of type 1 (insulin-dependent) diabetes mellitus in children.
We measured serum C-peptide, glucose, pH, islet antibodies and insulin antibody binding at diagnosis in 84 children with Type 1 (insulin-dependent) diabetes. In a subgroup of 33 children, residual insulin secretion (basal and peak C-peptide response to Sustacal), insulin antibody binding and HbA1c were measured at 10 days, 1, 3, 6 and 12 months. At presentation C-peptide correlated positively with age at onset and negatively with the blood glucose concentration. Median C-peptide concentration at diagnosis was low, rose significantly (p less than 0.05) at 10 days, reached a maximum at 1-3 months and declined gradually to 1 year. C-peptide concentration both at diagnosis and at 10 days correlated with that at 3 and 6 months. Of the factors investigated, only age (p less than 0.005) and sex (higher in females, p less than 0.01) were found to have a significant influence on basal/peak C-peptide levels throughout the first year. In particular there was no relationship between C-peptide, HbA1c and insulin dose during this period. A peak C-peptide response at 3-6 months greater than/less than 0.32 nmol/l was used to divide the group into two: 16 had a peak response less than 0.32 nmol/l (low secretors) while in 17, the peak C-peptide was greater than 0.32 nmol/l (high secretors). While the low secretors had significantly (p less than 0.05) lower C-peptide levels during the first year, there were no differences between low and high secretors in HbA1c or insulin dose.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Autoantibodies; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Prospective Studies | 1987 |
Diminished complications in a non DR3 DR4 family with insulin-dependent diabetes.
A family is reported in which the mother and both of her children developed insulin-dependent diabetes mellitus between 9 and 19 months of age, reflecting the importance of heredity in the natural history of this disease. That overt complications of diabetes were not present in any of the individuals, and that blood sugars were maintained close to normal on relatively small amounts of exogenous insulin, suggests a protective function in these patients related to residual secretion of insulin by beta cells. Human lymphocyte antigen (HLA) typing in this family showed that, although the diabetic children had identical HLA types, neither the mother nor her children possessed the diabetes-associated antigen HLA-DR3 or HLA-DR4. This raises the possibility that selective loss of diabetes-susceptible fetuses (suggested to be responsible for the low risk of diabetic mothers producing diabetic offspring) may be influenced by the HLA type of the mother. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Glycated Hemoglobin; HLA-DR Antigens; Humans; Infant; Islets of Langerhans; Male | 1987 |
Residual beta-cell function in children with type 1 diabetes: measurement and impact on glycemic control.
We studied residual beta-cell function in 84 children with IDDM to assess (1) relationship between basal and stimulated C-peptide concentrations; (2) reproducibility of testing (Group 1, n = 20); (3) the effect of exogenous insulin on test interpretation (Group II, n = 20); and (4) impact on metabolic control. Sustacal (a mixed liquid meal) was utilized as the test stimulus. In C-peptide positive subjects (n = 44) there was a strong correlation between basal and peak C-peptide concentrations (r = 0.88, p less than 0.001). In Group 1 subjects, Sustacal proved to be a highly reproducible test stimulus producing identical results on two tests 7-14 days apart. The results of the tests were not affected by the administration of subcutaneous regular insulin prior to the second test in Group II. Peak C-peptide correlated inversely with HbA1, insulin dose, and disease duration (r = -0.29, -0.40, and -0.33 respectively, p less than 0.05) and positively with age (r = 0.34, p less than 0.05). We conclude that Sustacal is a highly reproducible stimulus to residual beta-cell function in IDDM and is not affected by exogenous insulin. This residual insulin secretion has a small but significant effect on glycemic control. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male | 1987 |
Residual insulin secretion in adolescent diabetics after remission.
Twenty four hour blood glucose profiles were compared in two groups of insulin dependent adolescent diabetic patients who were beyond their initial partial remission phase. In the group with persistent endogenous insulin secretion, blood glucose profiles were significantly lower but the difference was small and not reflected in average 24 hour concentrations of glucose nor glycosylated haemoglobin. Endogenous insulin secretion must be considered in studies of metabolic control after the remission period but the effect on overall glucose control is probably clinically unimportant. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion | 1987 |
Serum antibody-bound insulin as a measure of insulin antibodies in diabetic children.
The usefulness of the measurement of serum antibody-bound and total immunoreactive insulin (IRI) concentrations in the assessment of insulin antibodies was evaluated in a material comprising 49 insulin-dependent diabetic children with a mean age at onset of 8.6 years (range 0.8-16 years) treated with highly purified porcine insulins. Serum antibody-bound and total IRI concentrations of individual patients were compared with insulin antibody levels measured with 3 different insulin antibody assays. The correlation coefficients of insulin antibody levels with concentrations of serum antibody-bound IRI ranged from 0.75-0.79. In serum samples with moderate or high insulin antibody levels most of the insulin was in the form of insulin-insulin antibody immunocomplexes. Thereby a very close correlation was found between antibody-bound and total serum IRI concentrations (r = 0.98) in this material. Residual endogenous insulin secretion decreased with increasing duration of diabetes. No significant correlation was found between the duration of diabetes and serum antibody-bound IRI concentrations. High serum antibody-bound IRI concentrations were associated with low glucagon-stimulated plasma C-peptide levels. Although the determination of serum antibody-bound IRI concentrations does not characterize insulin antibodies with regard to binding capacity and affinity constants, it yields information of the actual degree of insulin binding in the circulation. This information may be useful in assessing the benefits of transferring diabetics with high insulin antibody titers from conventional to highly purified porcine or human insulin therapy. Topics: Adolescent; Binding Sites, Antibody; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Infant; Insulin; Insulin Antibodies; Insulin, Regular, Pork; Male | 1987 |
C-peptide response to glycaemic stimuli.
Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Food; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Male | 1987 |
Serum lipid and lipoprotein levels in long-term insulin-dependent diabetes mellitus. Relation to residual insulin secretion, microvascular lesions and environmental factors.
The aim of the present study concerning patients with long-term insulin-dependent diabetes mellitus was to determine whether the serum lipid and lipoprotein concentrations differ in subjects with and without residual insulin secretion. We also investigated whether factors such as sex, smoking, physical activity and microvascular lesions were associated with particular lipoprotein profiles. C-peptide excretion (greater than or equal to 0.2 nmol) in 24-hour urine samples was used as an indicator of residual insulin secretion. Twenty-two pairs of patients with and without residual insulin secretion matched for age at onset and disease duration were participating in the investigations of glycaemic control and microvascular lesions. The HbA1c was significantly lower in C-peptide excretors than in the non-excretors (6.9 +/- 0.3 vs. 7.9 +/- 0.3%, p less than 0.025). The lipids and lipoprotein fractions were all within normal limits. The HDL2/3 ratio was significantly higher in C-peptide excretors than in non-excretors (1.72 +/- 0.28 vs. 1.10 +/- 0.09, p less than 0.05). Multiple regression analysis showed that factors, such as physical activity, body mass index and glycaemic control could explain more of the variation in the different lipid and lipoprotein fractions than residual C-peptide excretion alone. The only fraction correlating with C-peptide excretion was HDL3 cholesterol. It is concluded that minute residual insulin secretion per se is of minor importance for the regulation of lipids and lipoproteins. Glucose control and residual insulin secretion together with environmental factors seem to be of great importance for the regulation of the lipid and lipoprotein levels in insulin-dependent diabetes mellitus. Topics: Alcohol Drinking; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Female; Humans; Insulin; Insulin Secretion; Lipids; Lipoproteins; Male; Physical Exertion; Risk Factors; Smoking | 1987 |
Evidence against an immunogenetic basis for diabetes in chronic pancreatitis.
A possible immunogenetic basis for diabetes in chronic pancreatitis was explored by studying 19 patients with both disorders, most of whom required treatment with insulin. In contrast to patients with insulin-dependent (Type 1) diabetes, patients with diabetes and chronic pancreatitis had residual beta cell function but blunted C-peptide responses to intravenous glucagon, absence of circulating islet cell antibodies, and HLA-DR types similar to control subjects and patients with chronic pancreatitis without diabetes. Diabetes complicating chronic pancreatitis is therefore not associated with the biochemical or immunogenetic markers characteristic of Type 1 diabetes. Topics: Adult; Aged; Autoantibodies; Blood Glucose; C-Peptide; Chronic Disease; Cytoplasm; Diabetes Mellitus, Type 1; Female; HLA-DR Antigens; Humans; Islets of Langerhans; Male; Middle Aged; Pancreatitis | 1987 |
[Insulin secretion and action in acromegaly].
17 patients with active acromegaly (7 of them had diabetes mellitus, too), 13 patients with type I diabetes mellitus and 20 healthy controls were examined. The residual beta-cell secretion was determined by venous Tolbutamide test and the insulin sensitivity was determined by euglycemic clamp-technique. A positive correlation was found between the growth hormone level and prolactin and the size of the basic insulin secretion. In acromegaly (with or without diabetes) the sensitivity of beta-cell apparatus towards the stimulant Tolbutamide is preserved but the insulin reserves are diminished. There exists a positive correlation between the growth hormone level and the degree of insulin resistance and between the increased prolactin level and the degree of insulin resistance in acromegalic patients. Topics: Acromegaly; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Growth Hormone; Humans; Insulin; Insulin Secretion; Male; Prolactin; Time Factors; Tolbutamide | 1987 |
[Biological significance of the endogenous secretion of insulin in response to breakfast in diabetic children].
In 20 insulin dependent diabetics and in eight age-matched healthy children, we have measured basally HbA1 and the plasma lipid profile; and both basally and after a standard breakfast of 400 cal, blood glucose, C-peptide (CPR), immunoreactive glucagon (IRG), growth hormone and nonesterified fatty acids (NEFA). No difference was found in the lipid profile of diabetic and non diabetic children. In diabetics basal blood glucose was significantly correlated to both basal C-peptide (r = 0.5332, p less than 0.05) and to the ratio C-peptide/glucagon (r = 0.8563, p less than 0.01). The C-peptide response to the breakfast was accompanied of a significant increase in IRG and NEFA in diabetics, while in non-diabetics there was no change in IRG and a significant decrease in NEFA levels. Diabetic children with basal C-peptide levels higher than 0.6 ng/ml had lower blood glucose levels (187 +/- 43 vs 315 +/- 20 mg/dl, p less than 0.02), but no difference in blood glucose or any other parameter was observed as a function of the increase in CPR after breakfast. From these results we conclude that the evaluation of residual B-cell function in diabetic children by measuring the C-peptide response to a provocative stimulus is not more informative than the single basal measurement of C-peptide and does not have an additional biological significance, at least in hyperglycaemic insulin dependent diabetic children. Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Food; Glucagon; Glycated Hemoglobin; Growth Hormone; Humans; Insulin; Male | 1987 |
Insulin-dependent ketosis-resistant diabetes in Ethiopia.
Anthropometric, clinical and biochemical findings were compared in 30 rural (group A), 18 urban insulin-requiring (group B) and 45 urban oral-agent-responsive (group C) newly diagnosed diabetics. Mean ages at onset were 28.3 +/- 12.0, 25.6 +/- 14.5 and 42.1 +/- 10.5 years respectively. The differences between A and C and between B and C were significant. Group A were poor and malnourished, with body mass index (BMI) 15.9 +/- 1.9 and 17.2 +/- 3.7 kg/m2 for males and females respectively, presented with a long history of classical diabetes without ketoacidosis and required insulin in modest doses. 3 of 10 cases had excess stool fat but none of 13 unselected cases had pancreatic calcification. Group C were better nourished, with BMI 22.6 +/- 2.8 and 22.4 +/- 4.5 kg/m2, and responded to oral agents. Group B, with BMI 17.2 +/- 2.6 and 18.6 +/- 3.1 kg/m2, required insulin for control but had C-peptide levels above 0.02 nmol/1 in 10 of 15 cases. Anthropometric indices for males, but not for females, were significantly lower in group A than in group B or C. There were significant differences in levels of glucose between A and B and A and C, free fatty acids between A and C and B and C, insulin between A and B and A and C and C-peptide between A and C and B and C. Of the 3 groups the rural type most closely resembled the tropical variants. Topics: Adolescent; Adult; Blood Glucose; Body Height; Body Weight; C-Peptide; Child; Diabetes Mellitus, Type 1; Ethiopia; Fatty Acids, Nonesterified; Female; Humans; Insulin; Male; Middle Aged; Nutritional Status; Skinfold Thickness | 1987 |
Enhanced hepatic insulin sensitivity, but peripheral insulin resistance in patients with type 1 (insulin-dependent) diabetes.
Sensitivity to insulin in vivo was studied in 8 normal weight C-peptide negative Type 1 (insulin-dependent) diabetic patients (age 23 +/- 1 years, diabetes duration 6 +/- 2 years), and in 8 age, weight and sex matched healthy subjects, using the euglycaemic clamp and 3-3H-glucose tracer technique. Prior to the study diabetic patients were maintained normoglycaemic overnight by a glucose controlled insulin infusion. Sequential infusions of insulin in 3 periods of 2 h resulted in mean steady state insulin levels of 12 +/- 2 versus 11 +/- 1, 18 +/- 2 versus 18 +/- 2 and 28 +/- 3 versus 24 +/- 2 microU/ml in diabetic patients and control subjects. Corresponding glucose utilization rates were 2.4 +/- 0.2 versus 2.4 +/- 0.1, 2.4 +/- 0.2 versus 3.0 +/- 0.3 and 2.9 +/- 0.3 versus 4.6 +/- 0.6 mg.kg-1.min-1, p less than 0.02. Portal insulin values in the three periods were calculated to 12 +/- 2 versus 25 +/- 3, 18 +/- 2 versus 32 +/- 3 and 28 +/- 3 versus 37 +/- 3 microU/ml in the diabetic patients and control subjects using peripheral insulin and C-peptide concentrations and assuming a portal to peripheral insulin concentration gradient of 1 in diabetic patients and of 2.4 in control subjects. Corresponding glucose production rates were 2.5 +/- 0.2 versus 2.4 +/- 0.1, 1.6 +/- 0.1 versus 0.9 +/- 0.2 and 0.7 +/- 0.1 versus 0.4 +/- 0.2 mg.kg-1.min-1.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Glucose; Humans; Insulin; Insulin Resistance; Liver; Male | 1987 |
Serum fructosamine level as a marker of glycemic control in diabetic patients with and without a residual C-peptide secretion.
Serum fructosamine was determined in 115 diabetic patients with a C-Peptide secretion (0.84 +/- 0.06 pmol/ml, mean +/- SEM) (Group A) and in 30 type I C-peptide negative totally insulin-dependent subjects (less than 0.05 pmol/ml) (Group B). A significant correlation between fructosamine and HbA1 values (r = 0.70, p less than 0.001) was evidenced in Group A. In contrast, such a correlation was not found in Group B (r = 0.33, p greater than 0.05). Fructosamine levels were also in good agreement with the physician's ratings of the degree of glycemic control in Group A, but not in Group B. It is concluded that the fructosamine measurement represents a complement rather than an alternative to HbA1, in particular in unstable diabetic patients. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fructosamine; Glycated Hemoglobin; Hexosamines; Humans | 1987 |
Psychological adjustment and diabetic control.
Glycosylated haemoglobin concentrations, C peptide secretion, insulin dose, psychiatric state, intellectual functioning, and the extent to which the implementation of the diabetic regimen was shared between parent and child were studied in a cross sectional study of 50 children with diabetes aged 6-16. Indications of psychological disturbance in the children and their parents predicted low glycosylated haemoglobin concentrations in the children, and accounted for 44% of variance in blood glucose control. The child's early and independent participation in the implementation of the diabetic regimen was associated with poor control. Topics: Adaptation, Psychological; Adolescent; Affective Symptoms; C-Peptide; Child; Child Behavior Disorders; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Male; Parents | 1987 |
Heterogeneity of immunoreactive gastric inhibitory polypeptide in the plasma of newly diagnosed type 1 (insulin-dependent) diabetics.
The aim was to compare the three molecular forms of plasma immunoreactive gastric inhibitory polypeptide (IR-GIP) i.e. void volume (Vo), 8 and 5 kDa IR-GIP, found in type 1 diabetics with those found in normal subjects. Plasma from 6 non-fasting newly diagnosed ketotic type 1 diabetics obtained before and 1 h after a test meal given at start of insulin treatment, and before and 1 h after a test meal given after one and seven days of insulin treatment, respectively, was gel filtered and so was plasma from 6 normal subjects. The immunoreactivity in the effluents was measured with five different antisera. The elution positions of the three peaks were similar in controls and diabetics. With any given antiserum none of the components differed significantly as to amount of immunoreactivity between diabetics and controls, neither after the meals nor in the fasting state. The amount of Vo did not change in response to the meal, whereas the 8 and 5 kDa forms in the diabetics increased similarly to the increase in normals, also during ketosis. The Vo component did not differ significantly between diabetic and normal subjects, but it decreased significantly after start of insulin treatment. In the non-fasting, ketotic state before start of insulin treatment, no IR-GIP form was elevated significantly above normal postprandial levels. We conclude that the molecular forms of IR-GIP are similar in type 1 diabetics and normal subjects, but the molecular forms measured and their relative amounts vary according to which antiserum is used. The present study does not support that lack of insulin and ketosis markedly influence IR-GIP in plasma. Topics: Adult; Blood Glucose; C-Peptide; Chromatography, Gel; Diabetes Mellitus, Type 1; Female; Gastric Inhibitory Polypeptide; Humans; Insulin; Male; Molecular Conformation; Radioimmunoassay | 1987 |
Time course of islet cell antibodies and beta-cell function in non-insulin-dependent stage of type I diabetes.
The time course of islet cell antibodies (ICA) and serum C-peptides responses (CPRs) to oral glucose tolerance tests (OGTTs) were studied prospectively up to 60 (mean 35) mo in 32 ICA-positive subjects [28 with non-insulin-dependent diabetes (NIDDM) and 4 subjects with impaired glucose tolerance (IGT); mean age 45 yr], 96 matched subjects [56 with NIDDM, 8 with IGT, and 32 normal first-degree relatives of patients with insulin-dependent diabetes (IDDM); mean age 45 yr] who were negative for ICA at the beginning of the study. In addition, the effects of human leukocyte antigens (HLA) on the time course of ICA and beta-cell function were evaluated. In 10 subjects (8 with NIDDM and 2 with IGT) who were ICA positive, ICA became undetectable, even by sensitive ICA assay, 15 +/- 2 mo (mean +/- SE) after initiation of this study. In these subjects, integrated serum CPR values (sigma CPR) and 2-h blood glucose values in response to OGTTs improved significantly (P less than .05-.01). In contrast, the remaining 22 subjects who were ICA positive were persistently positive for ICA. CPR and blood glucose responses deteriorated progressively in these 22 subjects, and 7 subjects in this group progressed to the insulin-dependent state. Serum CPR and blood glucose responses to OGTTs showed no remarkable changes in 64 patients (56 with NIDDM and 8 with IGT) and 32 normal first-degree relatives of patients with IDDM who remained negative for ICA throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Antibodies; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; HLA Antigens; HLA-B Antigens; HLA-DR Antigens; Humans; Islets of Langerhans; Male; Middle Aged | 1987 |
[C-peptide determination in diabetics for the evaluation of insulin requirements].
45 non-insulin dependent diabetic subjects with "secondary failure" of oral treatment were observed for 2 years; during this period 23 of the 45 became insulin requiring. Plasma C-peptide concentrations at study entry and several clinical parameters of the patients were analysed statistically using discriminant analysis to test their value in predicting the need for later insulin therapy. The results demonstrated the fasting C-peptide concentrations and, independently of this, the simultaneously measured glucose level had a significant predictive power, e.g. only patients with fasting glycemia of greater than 12 mmol/l and C-peptide concentrations exceeding 700 pmol/l did not require insulin during follow-up. Increased C-peptide concentrations pointed to a predominance of insulin resistance which correlated with an increased chance of being treatable without insulin. A further group of 44 elderly, insulin-treated diabetic subjects were examined for clinical markers of type 1 and type 2 diabetes when these patients were separated into type 1 and 2 diabetes according to their fasting C-peptide concentrations. It was demonstrated that age, weight and duration of diabetes did not significantly differ between the 2 types of diabetes in this group of patients. The studies demonstrate that determination of plasma C-peptide concentration is a valuable tool in distinguishing the two types of diabetes (type 1 and type 2). This distinction has clinical implications with regard to genetic counselling or the search for other endocrinopathies. In addition, fasting C-peptide measurement is a valuable tool, in conjunction with blood sugar determination, in deciding whether patients with secondary failure of oral antidiabetic treatment require long-term insulin therapy. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans; Insulin; Insulin Resistance; Middle Aged | 1987 |
Plasma C-peptide and insulin responses to intravenous glucagon stimulation in idiopathic haemochromatosis.
Beta-cell reserve was investigated in 15 patients with proven idiopathic haemochromatosis (IHC) (7 normoglycaemic haemochromatotic patients, 4 non-insulin-requiring diabetics and 4 insulin-requiring diabetics) by measuring the response of plasma C-peptide, insulin and glucose to a 2 mg intravenous bolus of glucagon, and compared with that in 5 lean normal subjects. The corresponding C-peptide/insulin molar ratios were also calculated. Despite the significant fasting hyperglycaemia in the insulin-requiring haemochromatotic diabetics, mean fasting C-peptide concentrations were similar in all four groups. However, after glucagon stimulation the C-peptide response was significantly reduced in the insulin-requiring group over the whole period of observation. A trend in insulin response to glucagon was noted, with the highest values in the non-diabetic haemochromatotic patients, followed by the controls and then by the non-insulin-requiring diabetics, although there were no significant differences. In contrast, C-peptide/insulin molar ratios after glucagon were significantly reduced in the normoglycaemic IHC group. These results suggest the presence of at least two abnormalities of insulin metabolism in IHC--a progressive reduction in beta-cell function and a diminished rate of removal of insulin by the liver. Topics: Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Hemochromatosis; Humans; Insulin; Male; Middle Aged; Time Factors | 1987 |
Estimation of B-cell function by the urinary excretion rate of C-peptide in diabetic patients: comparison with C-peptide response to glucagon and to a mixed meal.
This study examined the relationship between the C-peptide response to intravenous glucagon and mixed meal stimulation and the 24 h urinary excretion rate of C-peptide and its urinary excretion during the glucagon test in nine control subjects, eighteen Type 1 (insulin-dependent) and twenty-two Type 2 (non-insulin-dependent) diabetic patients. Compared to controls (61.0 +/- 7.1 micrograms), the 24-h urine excretion rate of C-peptide was 8.2 +/- 3.1 micrograms (p less than 0.001) in Type 1 and 89.8 +/- 12.9 micrograms (p = NS) in Type 2 diabetic patients. C-peptide urinary excretion rate during the glucagon test was 6.92 +/- 1.11 micrograms, 0.42 +/- 0.10 microgram (p less than 0.001) and 6.47 +/- 1.13 micrograms (p = NS) respectively. Fasting serum C-peptide values were 1.53 +/- 0.16 ng/ml in controls, 0.42 +/- 0.09 ng/ml in Type 1 (p less than 0.0001) and 2.08 +/- 0.22 ng/ml in Type 2 diabetics (p = NS); C-peptide areas under the curve after glucagon stimulation were, respectively, 241.6 +/- 20.3 ng/ml, 29.2 +/- 5.9 ng/ml (p less than 0.0001) and 170.9 +/- 17.9 ng/ml (p less than 0.03) and after the meal test they were 204.7 +/- 15.6, 68.7 +/- 19.8 ng/ml (p less than 0.0001) and 265.5 +/- 32.9 ng/ml (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Food; Glucagon; Humans; Islets of Langerhans; Male; Obesity | 1987 |
Reduced urinary insulin clearance in patient with abnormal insulinemia.
We recently reported a new case of abnormal insulinemia with LeuA3 insulin. Herein, we measured urinary insulin clearance during oral glucose tolerance tests in proband with abnormal insulinemia (44-yr-old female), three affected family members, two unaffected family members, two other hyperinsulinemic patients with obesity, five non-insulin-dependent diabetic patients, and five normal control subjects. Urinary insulin-to-creatinine clearance ratio in the proband and her affected family members was 0.22 X 10(-3) +/- 0.07 (mean +/- SD, n = 4) and was markedly reduced compared with those of other groups: 1.73 X 10(-3) in two unaffected family members, 2.77 X 10(-3) in two other hyperinsulinemic patients with obesity, 2.99 X 10(-3) +/- 1.48 in five non-insulin-dependent diabetic patients, and 2.54 X 10(-3) +/- 0.67 in five normal control subjects. In contrast, urinary C-peptide clearance in these groups was not significantly different from controls. Binding of immunopurified insulins extracted from urine of the patients with abnormal insulinemia to guinea pig kidney membrane was slightly decreased (71% of standard insulin), in contrast with the observation that serum insulin of the proband had much less receptor-binding activity. Reverse-phase HPLC analysis of the immunopurified insulin of the proband revealed that the ratios of normal insulin to abnormal insulin were 8:3 in urine and 1:7 in serum, respectively. These results suggest that excretion of abnormal insulin in urine is much less than that of normal insulin. Topics: Adult; Animals; C-Peptide; Creatinine; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Guinea Pigs; Humans; Hyperinsulinism; Insulin; Kidney; Male; Metabolic Clearance Rate; Obesity; Radioimmunoassay; Radioligand Assay | 1987 |
Effect of an in-patient education programme upon the knowledge, behaviour and glycaemic control of insulin dependent diabetic patients.
The aim of this study was to evaluate the efficiency of a diabetes education programme (5 days in hospital) in type I diabetic patients by comparing their diabetes-related knowledge, behaviour and the level of HbA1 before with that 6 months and 1 year after the teaching session. The patients were divided into 2 groups according to whether they answered a questionnaire after 6 months (group I; 41 "responder" patients) or not (group II; 38 "non-responder" patients). Their usual regime of insulin therapy (2 daily injections of a mixture of regular and intermediate-acting insulins) was not modified during their hospitalization for teaching; the total daily doses of insulin and the percentages of regular insulin were comparable before and after the teaching session. In group I, we observed an improvement in knowledge and behaviour indices (evaluated by a written questionnaire) from 69 +/- 3 and 67 +/- 4% (mean +/- SEM) before the teaching session to 86 +/- 2 and 85 +/- 2% 6 months after, respectively (p less than 0.001). HbA1 decreased from 12.1 +/- 0.3% to 11.2 +/- 0.3% (p less than 0.05) and to 10.7 +/- 0.4% (p less than 0.025) after 6 and 12 months respectively. This improvement was observed in patients with or without residual insulin secretion. In group II patients, the index of knowledge increased similarly from 67 +/- 4 to 85 +/- 2% (p less than 0.001). No significant decrease of HbA1 was observed in this group after 6 and 12 months, however whether the patients possessed residual insulin secretion or not.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Inpatients; Male; Patient Compliance; Patient Education as Topic; Patients | 1987 |
Reduction and recovery of plasma 1,5-anhydro-D-glucitol level in diabetes mellitus.
The plasma concentration of 1,5-anhydro-D-glucitol (AG) was measured in 135 newly diagnosed patients who were referred for oral glucose tolerance tests. AG concentrations in the nondiabetic patients indicated that the mean value of normal AG concentration was 21.8 micrograms/ml (SD = 5.9 micrograms/ml, range 9.6-38.8 micrograms/ml). This distribution of AG concentration was significantly different from that in patients with impaired glucose tolerance (IGT) (13.3 +/- 5.4 micrograms/ml) and definitely different from that in diabetic patients (2.1 +/- 1.8 micrograms/ml). In a standard glucagon test, it was suggested that the decrease of plasma AG was affected not only by glycemic control of the patients but also by pancreatic cell secretory activity. The reduction of AG concentration was more marked in IDDM patients than in NIDDM patients. In longitudinal studies, AG concentration was shown to be sensitive to glycemic control. However, its recovery showed a tendency toward much delay after the improvement of fasting blood glucose or HbA1 concentrations. On the other hand, AG concentration showed negligible diurnal change and no immediate change as a result of diet, oral glucose load, or acute shift of the insulin level in both normal and diabetic subjects. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Blood Glucose; C-Peptide; Deoxy Sugars; Deoxyglucose; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Longitudinal Studies; Male; Middle Aged; Rats | 1987 |
Clinical characteristics in the discrimination between patients with low or high C-peptide level among middle-aged insulin-treated diabetics.
We compared sensitivity, specificity and accuracy of selected clinical characteristics (age at diagnosis, initiation of permanent insulin therapy from diagnosis and degree of obesity) in the discrimination between diabetics with low or high fasting or post-glucagon C-peptide level in a population of 171 middle-aged insulin-treated diabetics (81 men, 90 women) living in East Finland. Individual clinical criteria were poor discriminators alone but their combinations gave high specificity for the low and high fasting and post-glucagon C-peptide classes. The specificity and the accuracy of combined criteria seemed to be somewhat higher among male than among female insulin-treated diabetics. The association between clinical characteristics and fasting or postglucagon C-peptide classes seemed to be similar. Topics: Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Female; Glucagon; Humans; Male; Middle Aged; Sex Factors | 1987 |
C-peptide measurement in the differentiation of type 1 and type 2 diabetes mellitus--correction and comment.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Humans | 1987 |
Urinary C-peptide excretion at onset of insulin dependent diabetes mellitus in children.
The 24-hour urinary excretion of C-peptide and the plasma C-peptide concentration were measured at the onset of insulin dependent diabetes mellitus (IDDM) in children. The excretion of C-peptide was twice as high as that found in normal control subjects, whereas the plasma C-peptide values were markedly lower, indicating increased urinary leakage of C-peptide in this phase of the disease. In the diabetic children under seven years of age the mean value of C-peptide excretion was clearly lower than in the older children. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Male | 1987 |
Outcome of the glucagon test depends upon the prevailing blood glucose concentration in type I (insulin-dependent) diabetic patients.
The outcome of 97 paired glucagon and meal tests was related to the prevailing fasting blood glucose concentrations on the two test days. At blood glucose concentration less than 7 mmol/l both the C-peptide responses and the maximal (6 min) C-peptide concentrations during the glucagon tests were significantly lower than the corresponding values found during the meal tests. During the glucagon tests, a direct relationship was found between the responsiveness of the pancreatic beta-cells and fasting blood glucose values when these were between 3 and 7 mmol/l. No significant difference was found between the outcome of the two tests when the fasting blood glucose concentration was greater than 7 mmol/l. The results indicate that the outcome of the glucagon test in Type I patients depends upon the prevailing fasting blood glucose concentration and that the predictive value of the glucagon test as to how the beta-cells will respond to a meal during everyday life is low when fasting blood glucose is less than 7 mmol/l. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Food; Glucagon; Humans; Male | 1987 |
Glycosylated haemoglobin and glucose intolerance in cystic fibrosis.
Sixty four patients, age range 1-20 years, with cystic fibrosis had their tolerance to glucose assessed according to their glycosylated haemoglobin (HbA1) concentrations. Raised concentrations were found in 24 (37.5%). Oral glucose tolerance tests were performed on 21 patients with raised HbA1 and 13 patients with normal HbA1 concentrations. C peptide responses were also measured to assess islet cell function. Patients with normal HbA1 had normal glucose tolerance and C peptide response. Seven of 21 patients with raised HbA1 concentrations were glucose intolerant. The remaining 14 patients with raised HbA1 concentrations had normal glucose tolerance but a reduced C peptide response, suggesting impaired islet cell function. There were no appreciable differences in the incidence of chest infections, respiratory function, and chest x-ray scores among patients with normal HbA1 concentrations, raised HbA1 concentrations, and normal oral glucose tolerant tests, and patients who were glucose intolerant. No correlation was found between HbA1 concentration and age or Shwachman score. Measuring HbA1 concentrations periodically is useful in detecting and monitoring glucose intolerance in patients with cystic fibrosis. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Cystic Fibrosis; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Infant | 1987 |
Complement-dependent antibody mediated cytotoxicity (C'AMC) in patients with newly diagnosed insulin-dependent diabetes mellitus.
Serum activities of complement-dependent antibody mediated cytotoxicity (C'AMC) were determined in 36 consecutive patients with newly diagnosed insulin-dependent diabetes mellitus (IDDM). The sequential exposure of 51Cr labeled neonatal rat islet cells to patient serum and rabbit complement revealed the presence of C'AMC in 28 IDDM subjects. The C'AMC titres ranged between 1:4 and 1:512 and were not related to the C'AMC activity of a given sample as measured at a standard dilution (1:4). In comparison to the clinical characteristics of 21 IDDM patients with negative C'AMC, higher C'AMC titres (greater than or equal to 1:32) were associated with a lower mean age at diagnosis of IDDM (12.2 +/- 2.1 vs. 19.0 +/- 2.3 years; p less than 0.05), with a higher frequency of infections up to 6 months prior to diagnosis (6 out of 11 vs. 3 out of 21 patients; p less than 0.05) and, although statistically not significant, a preponderance of female sex together with a decreased frequency of HLA-DR4. In contrast, fasting C-peptides levels, HLA-DR3 antigen frequency and Coxsackie B1-6 virus antibody titres were not related to the C'AMC titres. It is concluded that (1) C'AMC titration is superior to the detection of initial C'AMC levels for evaluating the strength of the complement-dependent humoral immune response towards islet cell surface (auto)antigen(s), and (2) infectious agents may be involved in eliciting a C'AMC response. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Complement System Proteins; Cytotoxicity, Immunologic; Diabetes Mellitus, Type 1; Female; Humans; Male | 1987 |
White cells transfusion in recent onset type 1 diabetes.
Two HLA-identical brothers developed Type 1 diabetes simultaneously. In the light of present knowledge of the pathogenesis of Type 1 diabetes, immunosuppression was adopted in one brother by means of white cell transfusion from the father. The other brother acted as a control. This immunosuppressive approach has been shown to be effective in kidney transplantation and, as far as Type 1 diabetes is concerned, in the BB Wistar rat. An immunological and metabolic follow-up study of 1 yr only revealed slight differences between the 2 brothers (who are both on insulin) but the pattern of lymphocyte activation appeared to become normalized earlier in the transfused brother. Topics: Adolescent; Adult; Blood Transfusion; C-Peptide; Diabetes Mellitus, Type 1; Humans; Immunity, Cellular; Immunosuppression Therapy; Insulin; Leukocyte Transfusion; Lymphocyte Activation; Male; T-Lymphocytes, Regulatory | 1986 |
Sulfonylurea therapy fails to diminish insulin resistance in type I-diabetic subjects.
To assess whether extrapancreatic effects of sulfonylureas in vivo are detectable in the absence of endogenous insulin secretion, insulin sensitivity was determined in six insulin-deficient type 1-diabetic subjects. Peripheral uptake and hepatic production of glucose and lipolysis were measured during hyperinsulinemia using the euglycemic clamp technique and 3-3H-glucose infusions twice, once during a period with glibornuride treatment (50 mg b.i.d.), and once without. Hepatic glucose production decreased in diabetic subjects during hyperinsulinemia (insulin infusion of 20 mU/m2 X min; plasma free insulin levels of 40 +/- 4 mU/l) from 2.9 +/- 0.6 mg/kg min to 0.2 +/- 0.1 mg/kg X min after 120 min, and plasma free fatty acid (FFA) concentrations decreased from 1.33 +/- 0.29 to 0.38 +/- 0.08 mmol/l. Hepatic production, peripheral uptake of glucose and plasma FFA concentrations before and during hyperinsulinemia were not influenced by pretreatment with glibornuride. Compared to 8 non-diabetic subjects, type 1-diabetics demonstrated a diminished effect of hyperinsulinemia on peripheral glucose clearance (2.4 +/- 0.04 vs 4.2 +/- 0.5 ml/kg X min, P less than 0.01), whereas hepatic glucose production and plasma FFA levels were similarly suppressed by insulin. The data indicate that sulfonylurea treatment did not improve the diminished insulin sensitivity of peripheral glucose clearance in type 1-diabetic subjects; insulin action on hepatic glucose production and lipolysis was unimpaired in diabetics and remained uninfluenced by glibornuride. Thus, extrapancreatic effects of sulfonylureas in vivo are dependent on the presence of functioning beta-cells. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glucose; Humans; Insulin; Insulin Resistance; Lipolysis; Liver; Male; Metabolic Clearance Rate; Middle Aged; Sulfonylurea Compounds | 1986 |
Reversal of insulin resistance in type 1 diabetes following initiation of insulin treatment.
The biological action and pharmacokinetics of insulin were assessed in nine type 1 (insulin-dependent) diabetic patients before and after 3 months conventional insulin treatment, and in seven age and weight-matched non-diabetic controls, by means of the euglycaemic insulin clamp technique. The mean (+/- S.E.) metabolic clearance rate of insulin, when infused at 1 mU/kg/min, was similar in untreated and treated diabetic patients and in controls (22.7 +/- 2.0, 19.3 +/- 3.8, and 22.9 +/- 3.3 ml/kg/min) but, when infused at 6 mU/kg/min, was greater (p less than 0.01 and less than 0.01) in untreated patients (18.0 +/- 2.5 ml/kg/min) than in treated patients (11.5 +/- 1.4 ml/kg/min) and controls (12.7 +/- 1.3 ml/kg/min). Insulin-mediated glucose disposal was reduced (p less than 0.01 and less than 0.01) at insulin infusion rates 1 and 6 mU/kg/min in untreated patients (18.5 +/- 1.9 and 33.8 +/- 4.5 mumol/kg/min) when compared with controls (35.8 +/- 3.4 and 62.0 +/- 4.7 mumol/kg/min) and was improved (p less than 0.01 and less than 0.01) following insulin treatment (36.1 +/- 4.6 and 64.8 +/- 4.2 mumol/kg/min). Daily insulin requirement fell by 33% following 3 months insulin treatment with improvement in mean HbA1 from 16.3 +/- 0.7 to 8.2 +/- 0.4%, but without significant increase in endogenous insulin secretion. The 'honeymoon phenomenon', which has traditionally been attributed exclusively to resurrection of endogenous insulin release, may also be related to normalization of insulin action following institution of insulin treatment. Topics: 3-Hydroxybutyric Acid; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Growth Hormone; Humans; Hydrocortisone; Hydroxybutyrates; Insulin; Insulin Infusion Systems; Insulin Resistance; Male; Metabolic Clearance Rate; Time Factors | 1986 |
Long-term survival of human fetal pancreatic tissue transplanted into an insulin-dependent diabetic patient.
The explants of two human fetal pancreases of 15 weeks gestational age were cultured for 6-7 days before being implanted in a 29-year-old insulin-dependent diabetic woman who had received a renal graft two months previously. One pancreas was placed in the flexor muscles of the forearm whilst the other was implanted in an omental pouch. To reduce the chances of rejection the tissue was cultured in vitro, the donor of the tissue placed in the forearm was DR antigen matched with the recipient and the patient remained on cyclosporin and prednisone therapy. At 3 months a mass developed in the forearm muscle at the site of transplantation, and continued to grow. Biopsy at 13 months showed a small area of original pancreas surrounded by a large collection of mature lymphocytes and fibrous tissue. A and D cells could be seen around pancreatic ducts but B cells and acinar tissue were absent. At no stage during follow-up was plasma C-peptide detected in the recipient. Topics: Administration, Oral; Adult; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Female; Fetus; Follow-Up Studies; Histocompatibility Testing; Humans; Immunosuppression Therapy; Islets of Langerhans Transplantation; Organ Culture Techniques; Prednisone | 1986 |
The effect of residual beta-cell function on the development of diabetic retinopathy.
The effect of residual B-cell function on retinopathy was evaluated in a cross-sectional study of 533 insulin-dependent diabetic patients (disease duration 0 to 45 years). One hundred and fifty-three patients with residual B-cell function, as evaluated by stimulated plasma C-peptide concentration, had lower prevalence of retinopathy than patients without B-cell function. The patients with B-cell function had a shorter duration of diabetes and were older at onset, but there was no difference in age at the time of the study. When patients with similar duration of diabetes were compared, no differences in the degrees of retinopathy could be demonstrated between patients with and without B-cell function. These results indicate that residual B-cell function does not protect against or delay the development of diabetic microvascular lesions. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Humans; Infant; Islets of Langerhans; Male; Middle Aged; Time Factors | 1986 |
[Polyneuropathy and residual insulin secretion in diabetes mellitus type I].
In 145 patients suffering from type-I-diabetes with or without signs or symptoms of polyneuropathy basal and glucose-glucagon-induced secretion of insulin was determined. Patients without remaining insulin secretion exhibited somewhat more often polyneuropathies, slowing of nerve conduction, or reduced respiratory heart arrhythmia. If diabetes lasts for more than 10 years, insulin secretion ist reduced to such a low level that its may not have any significant preventive capability with respect to polyneuropathy. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Glycated Hemoglobin; Humans; Insulin; Motor Neurons; Peroneal Nerve; Polyneuropathies; Synaptic Transmission | 1986 |
[Our experiences with pancreas transplantation in diabetic patients].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Follow-Up Studies; Humans; Insulin; Islets of Langerhans Transplantation; Quality of Life | 1986 |
Increased platelet thromboxane B2 production in newborn infants of diabetic mothers.
Platelet thromboxane B2 (TxB2) production, plasma concentrations of C-peptide and pancreatic glucagon as well as blood glucose levels were measured in 12 infants of insulin-dependent diabetic mothers and eight healthy controls at the age of two hours. Platelet TxB2 production (p less than 0.05) and plasma C-peptide levels (p less than 0.02) were significantly higher and blood glucose concentrations lower (p less than 0.002) in the infants of the diabetic mothers than in the controls. The data suggest that platelets of infants of diabetic mothers produce increased amounts of proaggregatory thromboxane A2, which may contribute to the hyperaggregation in these infants. Topics: Blood Glucose; Blood Platelets; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Blood; Glucagon; Humans; Infant, Newborn; Pancreas; Thromboxane B2 | 1986 |
[Complex evaluation of pancreatic function in insulin-dependent diabetes mellitus].
The time course of the concentration of immunoreactive insulin (IRI) and C-peptide in the plasma and erythrocytes and the blood sugar level in GTT per os were investigated. Altogether 73 healthy persons and 52 patients with a severe form of insulin-dependent diabetes mellitus were examined. To define the time course of changes in the concentration of the above values a rate gradient determined as a difference of changed concentration rate for the 1st and 2nd hour after load for each examined person, was proposed. The most significant differences in the healthy persons and patients were noted in the plasma IRI basal level and blood sugar basal levels. The rate gradient defined most completely the time course of carbohydrate metabolism. The gradients C-peptide had maximum difference in healthy persons and patients. The hormone and blood sugar levels characterized the condition of the examined persons, and rate gradients were indicative of the state of the blood sugar regulation system. Topics: Adult; Antigens; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Pancreas; Pancreatic Function Tests | 1986 |
Use of biosynthetic human C-peptide in the measurement of insulin secretion rates in normal volunteers and type I diabetic patients.
We undertook this study to examine the accuracy of plasma C-peptide as a marker of insulin secretion. The peripheral kinetics of biosynthetic human C-peptide (BHCP) were studied in 10 normal volunteers and 7 insulin-dependent diabetic patients. Each subject received intravenous bolus injections of BHCP as well as constant and variable rate infusions. After intravenous bolus injections the metabolic clearance rate of BHCP (3.8 +/- 0.1 ml/kg per min, mean +/- SEM) was not significantly different from the value obtained during its constant intravenous infusion (3.9 +/- 0.1 ml/kg per min). The metabolic clearance rate of C-peptide measured during steady state intravenous infusions was constant over a wide concentration range. During experiments in which BHCP was infused at a variable rate, the peripheral concentration of C-peptide did not change in proportion to the infusion rate. Thus, the infusion rate of BHCP could not be calculated accurately as the product of the C-peptide concentration and metabolic clearance rate. However, the non-steady infusion rate of BHCP could be accurately calculated from peripheral C-peptide concentrations using a two-compartment mathematical model when model parameters were derived from the C-peptide decay curve in each subject. Application of this model to predict constant infusions of C-peptide from peripheral C-peptide concentrations resulted in model generated estimates of the C-peptide infusion rate that were 101.5 +/- 3.4% and 100.4 +/- 2.8% of low and high dose rates, respectively. Estimates of the total quantity of C-peptide infused at a variable rate over 240 min based on the two-compartment model represented 104.6 +/- 2.4% of the amount actually infused. Application of this approach to clinical studies will allow the secretion rate of insulin to be estimated with considerable accuracy. The insulin secretion rate in normal subjects after an overnight fast was 89.1 pmol/min, which corresponds with a basal 24-h secretion of 18.6 U. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Infusions, Parenteral; Injections, Intravenous; Insulin; Insulin Secretion; Male; Mathematics; Metabolic Clearance Rate; Models, Biological; Recombinant Proteins | 1986 |
Transplantation of cultured human fetal pancreas into insulin-dependent diabetic humans.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Fetus; Humans; Organ Culture Techniques; Pancreas; Pancreas Transplantation; Pregnancy | 1986 |
Amino acid concentrations in maternal plasma and amniotic fluid in relation to fetal insulin secretion during the last trimester of pregnancy in gestational and type I diabetic women and women with small-for-gestational-age infants.
Free amino acid concentrations were determined in maternal plasma and amniotic fluid (AF) under standardized and unstressed conditions in four groups of women comprising 6 gestational and 13 type I diabetics, 10 women with small-for-gestational-age (SGA) infants, and 18 healthy control women between 36 and 39 weeks of gestation. Plasma values for branched chain amino acids (the sum of leucine, isoleucine and valine) did not differ significantly between the four groups. The corresponding values in AF were significantly higher (P less than 0.05) in the type I diabetic group and significantly lower (P less than 0.05) in the gestational diabetic group as compared to the control group. The mean AF C-peptide concentration was elevated but not significantly so in gestational (0.69 nmol/l) or type I diabetic (0.54 nmol/l) pregnancies and significantly lower (P less than 0.05) in women with SGA infants (0.28 nmol/l) as compared to the control group (0.38 nmol/l). There was a significant correlation between C-peptide in AF and branched chain amino acids in maternal plasma (r = 0.63; P less than 0.05) as well as to maternal blood glucose (r = 0.79; P less than 0.01) in the type I diabetic group, which merely suggests a greater beta cell reactivity to insulin secretagogues in offspring of diabetic mothers. The correlation between AF C-peptide and branched chain amino acids in maternal plasma was significantly inverse in women with SGA infants (r = -0.75; P less than 0.05). Both individual, branched chain, or total amino acid concentration in AF were unrelated to AF C-peptide. Topics: Adult; Amino Acids; Amino Acids, Branched-Chain; Amniotic Fluid; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetus; Humans; Infant, Newborn; Infant, Small for Gestational Age; Insulin; Insulin Secretion; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Third | 1986 |
Type I diabetes is characterized by insulin resistance not only with regard to glucose, but also to lipid and amino acid metabolism.
Resistance to the metabolic effects of insulin has been reported with regard to glucose disposal in type I diabetic patients (IDDM) even when they were euglycemic. Our aim was to study glucose, lipid, and amino acid metabolism during glucose clamping at multiple levels of insulin in 10 normal (N) and 6 IDDM patients. Blood glucose was maintained constant (4.7 mmol/liter) at three insulin plateaus (160 min each) [42 +/- 6 (SD) 89 +/- 11, and 1255 +/- 185 microU/ml in N and 36 +/- 4, 80 +/- 13, and 1249 +/- 107 microU/liter in IDDM]. Mean glucose disposal was 34 +/- 11, 69 +/- 10, and 84 +/- 22 mumol kg-1 min-1 in N and 16 +/- 5, 40 +/- 18, and 65 +/- 27 in IDDM, respectively. Baseline concentrations of blood lactate, pyruvate, alanine, and branched chain amino acids were 560 +/- 130, 36 +/- 9, 212 +/- 44, and 451 +/- 19 mumol/liter, in N and 793 +/- 179 (P less than 0.05), 45 +/- 14, 195 +/- 50, and 439 +/- 33 in IDDM, respectively. The maximum percent change of lactate during the euglycemic clamp was +147 +/- 23% in N and +75 +/- 15% (P less than 0.05) in IDDM; that of branched chain amino acids was -61 +/- 5% in N and -48 +/- 7% (P less than 0.01) in IDDM. Baseline concentrations of glycerol, FFA, and adipate were 44 +/- 15, 449 +/- 152, and 8 - 8 mumol/liter in N and 39 +/- 14, 473 +/- 44, and 41 +/- 14 (P less than 0.01) in IDDM. The maximum percent change of glycerol during the euglycemic clamp was -50 +/- 8% in N and -16 +/- 8% (P less than 0.01) in IDDM, that of FFA -98 +/- 3% in N and -70 +/- 4% in IDDM (P less than 0.05). No significant differences were found between N and IDDM with regard to blood concentrations of ketone bodies, citrate, ketoglutarate, and hydroxymethylglutaryl coenzyme A both before and during the euglycemic clamp. The lactate percent increase was significantly correlated to glucose disposal rate (P less than 0.001). The lactate turnover rate increased during the euglycemic clamp and was lower in IDDM than in N. We conclude that during euglycemic-multiple insulin clamp studies the greater lactate increase suggests that the flux of glycolysis is higher in N than in IDDM, tricarboxylic acid concentrations are comparable in N and IDDM, and FFA, glycerol, and branched chain amino acid decreases were less in IDDM than in N, suggesting that IDDM patients are resistant to insulin with regard to lipid and protein metabolism. The higher adipate basal values demonstrate enhanced omega-oxidation in IDDM. Topics: Adult; Amino Acids; Amino Acids, Branched-Chain; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Insulin; Insulin Resistance; Ketone Bodies; Lactates; Lactic Acid; Lipids; Male; Middle Aged | 1986 |
Residual B-cell function and glycaemic control in diabetic pregnancy.
Serum C-peptide immunoreactivity (CPR), mean blood glucose and blood glycosylated haemoglobin Hb A1c were measured in 23 insulin-dependent diabetic women at 11-12, 23-24, 33-34 and 37-38 gestational weeks in order to elucidate changes in residual B-cell function during pregnancy and their influence on the glycaemic control. CPR values generally increased at the 23-33 gestational weeks, with a significant difference between the mean of the peak values and the mean of the values at the first admission. When the subjects were divided into two groups on the basis of the residual B-cell function at the first admission, the glycaemic control during pregnancy was significantly better in those with higher residual B-cell activity. The overall prevalence of marked residual B-cell activity was higher than previously reported in non-pregnant insulin-dependent diabetic subjects. The results indicate clinically important enhancement in residual B-cell function during pregnancy. The mechanism of this improvement is poorly known although the more strict management of diabetes during gestation may be an important factor. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Death; Gestational Age; Glycated Hemoglobin; Humans; Infant, Newborn; Insulin; Islets of Langerhans; Pregnancy; Pregnancy in Diabetics | 1986 |
Residual insulin secretion in insulin dependent diabetes mellitus.
Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Infant; Infant, Newborn; Insulin; Insulin Secretion | 1986 |
Natural course of insulin resistance in type I diabetes.
To examine the natural course of insulin action in Type I diabetes, we followed 15 patients prospectively for one year after the diagnosis of diabetes and also performed a cross-sectional study of 53 additional patients who had had diabetes for 2 to 32 years. Two weeks after diagnosis, the rate of glucose uptake during hyperinsulinemia, a measure of insulin action, was 32 percent lower in the patients with diabetes than in 30 matched normal subjects (P less than 0.01), but it rose to normal during the subsequent three months. At three months after diagnosis, 9 of 21 patients (43 percent) were in clinical remission and did not require insulin therapy. In these patients, insulin action was 40 percent greater (P less than 0.002) than in the patients who continued to need insulin treatment. Fasting plasma C-peptide levels were slightly but not significantly higher in the patients who had a remission than in the other patients. In patients who had had diabetes for one year or more, insulin action was also reduced by an average of 40 percent (although there was considerable variation between patients), and it was inversely related to glycemic control and relative body weight. Thus, in patients with newly diagnosed Type I diabetes, a transient normalization of insulin action may occur after an initial reduction, along with a partial recovery of endogenous insulin secretion, and these events may contribute to the development of a clinical remission ("honeymoon" period). A majority of patients with diabetes of long duration are characterized by varying degrees of insulin resistance. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Resistance; Insulin Secretion; Male; Middle Aged; Prospective Studies; Remission, Spontaneous | 1986 |
The role of insulin antibodies in insulin treatment of type I diabetes.
We investigated equilibrium plasma binding patterns of insulin in 45 juvenile diabetics treated with conventional insulin preparations. Insulin binding parameters were evaluated by Scatchard analysis of the binding data. Stable diabetics had significantly lower equilibrium dissociation constants than labile, thus suggesting an enhanced insulin depot effect due to stronger insulin binding. Correlation of insulin binding data with a glycemic control index yielded a positive relationship between insulin antibody binding and the degree of glycemic control. Insulin neutralization as detected by a relationship between maximum binding capacity of high affinity antibodies and insulin requirement could only be found if patients with poor diabetes control were excluded. Similarly, the well-known promoting influence of residual beta-cell functional capacity (assessed by C-peptide levels) on diabetic stability was observed only after exclusion of patients with higher insulin antibody binding. These data suggest that insulin antibodies are influencing insulin treatment of diabetics in a dual way. They may neutralize therapeutic insulin but at the same time they exert an insulin-sparing action by improvement of diabetes control. Occasionally the latter effect may abolish the correlation between diabetes control and beta-cell functional capacity. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Glucagon; Glucose; Humans; Insulin; Insulin Antibodies; Mathematics | 1986 |
Evidence of an accelerated B-cell destruction in HLA-Dw3/Dw4 heterozygous children with type 1 (insulin-dependent) diabetes.
The possible association between residual B-cell function and specific HLA antigens in Type 1 (insulin-dependent) diabetes was studied in a cross-sectional series of 144 diabetic children and adolescents, as well as in a prospective series of 44 newly diagnosed diabetic subjects who were observed for the initial 2 years of their diabetes. In the cross-sectional study, the HLA-Dw3/Dw4 heterozygotes had a lower mean serum C-peptide concentration during 1980, 0.03 +/- 0.01 nmol/l (mean +/- SEM) vs. 0.09 +/- 0.01 nmol/l (p less than 0.02), as well as a lower 24-h urinary C-peptide excretion, 0.27 +/- 0.06 nmol/m2 vs. 1.34 +/- 0.19 nmol/m2 (p less than 0.05), than the other subjects. In addition, the Dw3/Dw4 heterozygotes had a clinical remission of shorter duration, 113 +/- 47 days vs. 203 +/- 22 days (p less than 0.05), and a higher mean glycosylated haemoglobin level during 1980, 14.8 +/- 0.05% vs. 13.7 +/- 0.2% (p less than 0.05), than those without the Dw3/Dw4 combination. In the prospective study the serum C-peptide concentrations were of the same magnitude in the Dw3/Dw4 heterozygotes and the other subjects during the first month. Subsequently the C-peptide concentrations in the subjects with the Dw3/Dw4 combination started to decrease 2 months earlier than in the other subjects. The Dw3/Dw4 children had a significantly lower serum C-peptide concentration at 21 months, 0.01 +/- 0.01 nmol/l vs. 0.13 +/- 0.02 nmol/l (p less than 0.01), and at 24 months, 0.03 +/- 0.01 nmol/l vs. 0.12 +/- 0.02 nmol/l (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Heterozygote; Histocompatibility Antigens Class II; HLA-DR3 Antigen; HLA-DR4 Antigen; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1986 |
Endocrine pancreatic function in insulin-dependent diabetic pregnant women.
In order to better understand the role of A- and B-cell function in diabetic pregnancy, we studied four groups of pregnant women at week 34-36 of gestation. Seventeen were healthy controls (C), 24 had gestational diabetes (GD), 16 had type 2 diabetes (NIDD) and 37 had type 1 diabetes (IDD). At times -20, 0, 20, 30, 45, 60, 90 and 120 min from the beginning of a 30 min infusion of 30 g of arginine intravenously, plasma glucose, glucagon (IRG) and C-peptide (CPR) were measured. Plasma glucose was higher in diabetic than in control subjects. IRG values were also higher in the GD and the NIDD women. CPR values were similar to, or slightly higher than control values in the GD and the NIDD and were much lower in the IDD women. All three variables increased during the arginine infusion in all groups, with the exception that CPR remained unchanged in the IDD. The CPR/IRG molar ratio was similar in control, GD and NIDD women; in the IDD, it was much smaller than in the other groups and was not affected by arginine. In all the diabetic patients, IRG was negatively correlated with the maternal weight gain and in the IDD IRG was positively correlated with the increase in the insulin need and with the CPR levels. In conclusion diabetes appeared to enhance the A-cell function also in pregnancy, possibly impairing the 'facilitated anabolism' and stressing the 'accelerated starvation' which are typical of normal pregnancy. Glucagon was confirmed as one possible determinant of the insulin resistance seen in diabetic pregnancy. Topics: Arginine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Islets of Langerhans; Pregnancy; Pregnancy in Diabetics | 1986 |
Plasma and urinary C-peptide in the classification of adult diabetics.
Plasma and urinary C-peptide determinations in the discrimination between insulin-requiring and non-insulin-requiring diabetes were elevated in 61 adult diabetics. Specimens for C-peptide determinations were taken on two consecutive days: on the first day plasma C-peptide concentrations were determined before and 6 min after intravenous glucagon administration. On the second day 2- and 4-h urinary C-peptide excretion was measured after an individual breakfast. Results of urinary C-peptide analyses were expressed as molar concentration and also as molar quantity excreted (without any corrections and related to creatinine excretion). Glucagon-stimulated plasma C-peptide turned out to be a reliable criterion for the detection of insulin requirement. Sixty-nine per cent of diabetics included in this study were classifiable by basal plasma C-peptide concentrations. Two-hour postprandial urinary C-peptide/creatinine quotient turned out to be slightly less sensitive (89%) than the glucagon test (94%) and of equal specificity (96%). Glucagon-stimulated plasma C-peptide and postprandial urinary C-peptide excretion correlated significantly among insulin-requiring diabetics (r = 0.73), but not among non-insulin-requiring diabetics (r = 0.23). We regard determination of stimulated plasma C-peptide as a primary investigation for the direct assessment of endogenous insulin secretory reserves for clinical management decisions. Determination of postprandial urinary C-peptide is applicable in selected situations for non-invasive assessment of insulin secretion. Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Glucagon; Humans; Insulin; Insulin Secretion; Middle Aged | 1986 |
C-peptide immunoreactivity and insulin content in the diabetic human pancreas and the relation to the stability of diabetic serum glucose level.
The content of insulin and C-peptide-like immunoreactivity (CPR) were determined in the tail of pancreas from 35 autopsied diabetic and 21 non-diabetic subjects. In the 28 diabetics who had been followed for more than 6 months, the relation between the amount of insulin or CPR in the pancreas and the stability of fasting serum glucose during diabetic life before death was analyzed together with the relation between the serum CPR response to the breakfast tolerance test before death and insulin content at autopsy. As an index of the instability of the blood sugar level, the standard deviation of the mean of 15 successive determinations of fasting serum glucose was used. Both insulin and CPR content in the pancreas were significantly decreased in diabetics as compared with non-diabetics. SD of the mean fasting serum glucose and insulin or CPR content in the tail of pancreas showed a significant inverse correlation on a logarithmic scale (P less than 0.01, r = -0.704 and P less than 0.01, gamma = -0.757, respectively). Serum CPR value during the breakfast tolerance test correlated significantly with the insulin content in the pancreas of diabetic subjects. These findings suggest that one of the causes of the instability of fasting serum glucose levels is the devastation of pancreatic beta-cells and that the pancreatic insulin content is logarithmically and inversely related to fluctuations in fasting serum glucose. Topics: Aged; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Fasting; Female; Food; Humans; Insulin; Liver Cirrhosis; Male; Middle Aged; Pancreas | 1986 |
Influence of age on insulin requirement in insulin dependent diabetes mellitus patients treated with CSII.
Topics: Adult; Age Factors; Autoantibodies; C-Peptide; Diabetes Mellitus, Type 1; Female; HLA Antigens; Humans; Insulin Infusion Systems; Islets of Langerhans; Male; Middle Aged | 1986 |
C-peptide in diabetes mellitus treated with insulin. A 3-year epidemiological study on the island of Falster, Denmark.
In a 3 yr prospective epidemiological study of 227 insulin-treated diabetics the clinical value of fasting C-peptide measurements for discriminating between insulin dependence and non-insulin dependence was assessed. A significant difference (p less than 0.01) in fasting C-peptide secretion was found between diabetics with an early onset age (less than 30 yr) and a late onset age (greater than or equal to 30 yr). Among diabetics with a late onset age (n = 124) 45% were classified as non-insulin dependent according to fasting C-peptide levels (greater than 0.40 pmol/ml) and characterized by overweight. Diabetics with C-peptide concentrations less than 20 pmol/ml were characterized by an early onset of diabetes mellitus (less than 30 yr), the duration of diabetes mellitus (greater than 5 yr), slight deviation from ideal weight, development of insulin antibodies and high daily insulin dosage. Among the 57 diabetics with a C-peptide level greater than 0.40 pmol/ml 31 accepted and could maintain good metabolic control in a period of 3 yr after change from treatment with insulin to treatment with oral hypoglycaemic agent and diet or diet regime alone. It is concluded that measurement of fasting C-peptide is of additional clinical importance for the choice of treatment of diabetics. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged; Prospective Studies | 1986 |
[Proinsulin secretion and proinsulin: C-peptide indicator in the sera of children with newly detected diabetes mellitus type 1].
Topics: C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Proinsulin | 1986 |
Ingestion of a mixed meal does not affect the metabolic clearance rate of biosynthetic human C-peptide.
The validity of C-peptide as a peripheral marker of insulin secretion during different physiological conditions depends on the demonstration that C-peptide clearance is constant under these circumstances. Recently biosynthetic human C-peptide, identical in structure to pancreatic human C-peptide, became available for use in human subjects. The present study was undertaken to determine if the metabolic clearance of C-peptide was altered by ingestion of a mixed meal. Eight insulin-dependent diabetic patients received constant iv infusions of biosynthetic human C-peptide which raised the plasma C-peptide concentration to a level of 3.8 +/- 0.2 (+/- SEM) pmol/ml. The MCR of C-peptide was 4.5 +/- 0.3 ml/kg X min. After steady state levels of C-peptide had been reached, each patient consumed a 530 calorie mixed meal. The plasma glucose concentration increased from a baseline value of 104.5 +/- 4.8 mg/dl to a 336 +/- 10 mg/dl 150 min later. This change in plasma glucose was not associated with a significant alteration in the plasma C-peptide concentration and the MCR of the infused C-peptide was not affected by meal ingestion (4.5 +/- 0.3 vs. 4.3 +/- 0.3 ml/kg X min). These results therefore support the validity of using C-peptide as a marker for changes in insulin secretion after mixed meals. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diet; Female; Humans; Male; Metabolic Clearance Rate; Recombinant Proteins | 1986 |
Practical aspects in performing the glucagon test in the measurement of C-peptide secretion in diabetic patients.
The secretion of plasma C-peptide after intravenous glucagon stimulation was studied in 15 insulin-treated diabetic patients with onset of diabetes after the age of 30. The mean stimulation of C-peptide secretion caused by glucagon given in the fasting state and by a standardized breakfast were similar. Low blood glucose values (less than 3.5 mmol/l) were found to suppress the stimulating action of glucagon on the pancreas almost completely. When the glucagon test was performed 1.5 hours after a standardized breakfast, the mean concentration of plasma C-peptide was 62% higher than in the test in the fasting state, showing that the stimulating actions of glucagon and breakfast on the secretion of insulin are additive. The results indicate that when determining the level of plasma C-peptide after stimulation with glucagon, in order to distinguish between insulin-dependent and non-insulin-dependent diabetic patients, it is critical to take into account the consequence of low blood glucose values and to standardize the test conditions in regard to pre-test meals. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Food; Glucagon; Humans; Male; Middle Aged | 1986 |
[C-peptide in type I diabetics].
Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Eating; Female; Humans; Male; Middle Aged; Time Factors | 1986 |
[C-peptide and the importance of its determination].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Pancreatic Function Tests | 1986 |
Congenital pancreatic hypoplasia: a syndrome of exocrine and endocrine pancreatic insufficiency.
We describe two brothers with small size at birth, early-onset insulin-dependent diabetes, and pancreatic exocrine insufficiency. In contrast to the findings in pancreatic aplasia, their serum C-peptide and glucagon levels were measurable. These findings, in concert with their clinical courses, are consistent with the diagnosis of congenital pancreatic hypoplasia. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; HLA Antigens; Humans; Male; Pancreas | 1986 |
Risk factors and markers associated with proliferative retinopathy in patients with insulin-dependent diabetes.
To define risk factors and markers associated with proliferative retinopathy (PR), we compared 44 insulin-dependent diabetic patients with PR with 45 matched patients without advanced retinopathy (NR). Glycemic control assessed by HbA1 measurements from 5 yr preceding diagnosis of PR was significantly worse than in NR patients. The NR patients had more frequently been treated with multiple daily insulin injections than the PR patients. About half of the PR patients had Albustix-positive proteinuria, and these patients were further characterized by an abnormal lipid profile in plasma and increased frequency of cardiovascular disease. In contrast, PR patients without proteinuria did not differ from NR patients in these variables. Sensorimotor and autonomic neuropathy were twice as frequent in the PR than in the NR group. There was no correlation between anti-insulin antibody titer, immune complexes, and the presence of PR, but T-lymphocyte response to different stimuli was slightly reduced in the PR patients. The anti-insulin-antibody titer correlated with duration of diabetes in the NR but not the PR group. The frequency of HLA-DRw8 was slightly higher in the PR group than in the NR group (16 vs. 0%, NS), but we could not confirm the previously suggested association between HLA-DR4 and PR. Serum C4 levels were low in the diabetics but did not differ between PR patients without proteinuria and NR patients. In conclusion, poor glycemic control was clearly associated with PR in this study, and attempts to prevent this hazardous complication should include means to improve insulin therapy. We did not find support for the view that susceptibility to PR is associated with any known HLA antigen(s).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Glycated Hemoglobin; HLA Antigens; Humans; Male; Middle Aged; Risk | 1986 |
Sulfonylurea stimulated C-peptide responses in insulin-dependent diabetic children.
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Male; Sulfonylurea Compounds | 1986 |
[Behavior of urinary C-peptide in type I diabetic subjects].
Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Creatinine; Diabetes Mellitus, Type 1; Fasting; Humans | 1986 |
Good diabetic control early in pregnancy and favorable fetal outcome.
This study of 74 diabetic pregnant women shows that tight maternal blood glucose control before the 32nd week of gestation significantly reduces the incidence of fetal macrosomia (11%) when compared with that of patients with fair to poor control before the 32nd week of gestation (44%, P less than .05) or with those whose good diabetic control was not achieved until after the 32nd week of gestation (34%, P less than .05). The macrosomic infant produced by a diabetic mother is associated frequently with an elevated amniotic fluid C-peptide level, which shows the evidence of intrauterine fetal hyperinsulinism. The use of tight diabetic control early in pregnancy to reduce the risk of fetal macrosomia and/or neonatal complications is of clinical importance in the management of diabetes in pregnancy. Topics: Amniotic Fluid; Birth Weight; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Gestational Age; Humans; Hypoglycemia; Infant, Newborn; Infant, Small for Gestational Age; Jaundice, Neonatal; Longitudinal Studies; Pregnancy; Pregnancy in Diabetics; Time Factors | 1986 |
Amniotic fluid C-peptide and cortisol in normal and diabetic pregnancies and pregnancies accompanied by fetal growth retardation.
The interrelationship between amniotic fluid (AF) concentration and content (AF X conc) of C-peptide and cortisol was studied in four groups of women comprising 10 gestational and 16 type-I diabetics, 11 women with intrauterine growth retarded fetuses (IUGR), and 17 healthy control women. Mean AF volume was significantly greater (P less than 0.05) in the type-I diabetic group than in the control group. Both concentration and content of AF C-peptide was significantly higher in the type-I diabetic group than in the control group (P less than 0.05 and P less than 0.01, respectively). The corresponding values were significantly lower in mothers with IUGR fetuses compared to controls (P less than 0.05). AF cortisol content was significantly higher (P less than 0.05) in the gestational diabetic group compared to the control group; there were no other significant differences between the groups regarding the cortisol concentration or content. Both cortisol and C-peptide contents were significantly interrelated in both control women (r = 0.68, P less than 0.01) and women with gestational (r = 0.68, P less than 0.05) and type-I diabetes (r = 0.63, P less than 0.01). The C-peptide/cortisol ratio was lowest in the IUGR group and highest in the type-I diabetic group. The same ratio was intermediate and almost equal in the control and gestational diabetic group. Both C-peptide and cortisol concentrations were unrelated to AF volume as well as infant birthweight. C-peptide content was significantly correlated to birthweight percentile in type-I diabetic women (r = 0.61, P less than 0.05). No such correlation was found in the three other groups. Topics: Amniotic Fluid; Birth Weight; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetal Growth Retardation; Fetus; Gestational Age; Humans; Hydrocortisone; Infant, Newborn; Pregnancy; Pregnancy in Diabetics | 1986 |
Interrelationship between amniotic fluid C-peptide and catecholamines in the last trimester of diabetic pregnancy.
Amniotic fluid concentration and content (amniotic fluid volume X concentration) of C-peptide and catecholamines (epinephrine, norepinephrine) and their interrelationship was studied in nine women with gestational diabetes, in 14 women with type I diabetes, and in 20 healthy control women between the thirty-sixth and thirty-ninth week of gestation. Mean amniotic fluid volume was significantly larger (p less than 0.05) in the type I diabetic group than in the control group. Mean concentration and content of amniotic fluid C-peptide were elevated in women with gestational diabetes, significantly so in women with type I diabetes (p less than 0.05) as compared with nondiabetic control women. Mean amniotic fluid catecholamine concentrations were lower, although not statistically so, in both insulin-dependent and gestational diabetic women than in control women. Mean amniotic fluid catecholamine content was higher, although not statistically so, in women with gestational diabetes than in control women. In the type I diabetic group, epinephrine content was significantly lower (p less than 0.05) and norepinephrine content significantly higher (p less than 0.05) than in the control group. A significant positive correlation between the content of norepinephrine and C-peptide was found in control women (r = 0.57; p less than 0.05) and in women with gestational diabetes (r = 0.75; p less than 0.05). The close interrelationship could indicate a parallel maturation of these two hormonal systems. Topics: Adult; Amniotic Fluid; C-Peptide; Catecholamines; Chromatography, High Pressure Liquid; Chromatography, Ion Exchange; Diabetes Mellitus, Type 1; Female; Humans; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Third; Radioimmunoassay | 1986 |
Metabolic and immunological effects of cyclosporin in recently diagnosed type 1 diabetes mellitus.
Cyclosporin 5-10 mg/kg daily was given for 2-8 months to twelve recently diagnosed type 1 diabetics from a mean of 49 +/- SE 14 days after the start of insulin therapy, which was regulated to give near-normal blood glucose and haemoglobin A1c values. Mean insulin dosage dropped from 46 +/- 5 U/day before cyclosporin treatment to 16 +/- 4 U/day by the 7th month. Four patients had a complete remission and the insulin needs of four more were cut by half. The remaining four did not have remissions. Initial basal and glucagon-stimulated C peptide concentrations were higher in those who went into remission than in those who did not; they rose during cyclosporin treatment in the former but not in the latter. OKT4+ lymphocyte functions were suppressed in all patients and OKT4/OKT8 ratios declined. Anti-beta-cell autoimmunity, as indicated by lymphocyte-induced inhibition of insulin release from mouse islet cells, declined in all patients who went into remission. No consistent trend was observed for anti-islet cell antibodies. In forty-four similar, but non-randomised, recently diagnosed diabetics treated with insulin alone, the incidence of remission was 6%. Topics: Adult; Autoantibodies; Blood Glucose; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Lymphocytes; Male | 1985 |
Cyclosporin in diabetes.
Topics: C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Humans | 1985 |
Disappearance and reappearance of islet cell cytoplasmic antibodies in cyclosporin-treated insulin-dependent diabetics.
In 68 newly diagnosed patients with insulin-dependent diabetes mellitus (IDDM) whose treatment included cyclosporin (CyA) the prevalence and mean titre of islet cell cytoplasmic antibodies (ICA) fell faster than they did in the 56 who received only insulin. However, in the CyA-treated patients the prevalence or titre of ICA at diagnosis did not correlate with beta-cell function as measured by glucagon-stimulated C-peptide levels; improvement and recovery of beta-cell function after 30 days of CyA therapy occurred despite the continued presence of ICA; and CyA-induced remission of IDDM (ie, glucagon stimulated plasma C-peptide levels greater than 0.6 pmol/ml) was not predicted by nor coincident with disappearance of ICA. Therefore, although CyA therapy was associated with a higher than expected frequency of remission and faster disappearance of ICA, the two observations were not temporally and may not be causally related. ICA should not be used to identify the target population for or to predict response to immunosuppressive therapy. The contribution of ICA to the pathogenesis of beta-cell destruction in IDDM needs serious re-examination. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Cyclosporins; Cytoplasm; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Time Factors | 1985 |
Retinopathy in mild diabetes, hypersomatotropinism, and hypoinsulinaemia.
Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Growth Hormone; Humans; Insulin | 1985 |
Coxsackie-B-virus-specific IgM responses, complement-fixing islet-cell antibodies, HLA DR antigens, and C-peptide secretion in insulin-dependent diabetes mellitus.
To evaluate the role of Coxsackie B viruses in the pathogenesis of insulin-dependent (juvenile-onset, type 1) diabetes mellitus (IDDM), attempts were made to correlate virus-specific IgM responses with HLA genes, autoimmune responses, and C-peptide secretion. HLA DR3, DR4, or both were present in 73 of 90 (81%) diabetic patients; 22 of 23 (96%) with Coxsackie-B-virus-specific IgM had at least one of these HLA types, compared with 51 of 67 (76%) without virus-specific IgM. There was no correlation between HLA A, B, or C types or immunoglobulin allotypes and virus-specific IgM responses. 16 of 22 (64%) patients with Coxsackie-B-virus-specific IgM compared with 26 of 72 (36%) without had complement-fixing islet-cell antibodies; no relation was found between virus-specific IgM and antibodies against thyroid or adrenal tissue or parietal cells. C-peptide secretion was significantly lower in patients with Coxsackie-B-virus-specific IgM. Topics: Adolescent; Adrenal Glands; Adult; Antibodies, Viral; Antibody Specificity; Autoantibodies; C-Peptide; Child; Complement Fixation Tests; Diabetes Mellitus, Type 1; Enterovirus B, Human; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Immunoglobulin M; Insulin Antibodies; Parietal Cells, Gastric; Thyroid Gland | 1985 |
Insulin-dependent?
Topics: Adult; Aged; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Middle Aged; Obesity | 1985 |
Anti-thymocyte globulin and prednisone immunotherapy of recent onset type 1 diabetes mellitus.
Increasing evidence that Type 1 (insulin dependent) diabetes mellitus is an autoimmune disease, together with successful cure/prevention in animal models of this disease (e.g. BB/W rat) has led to several trials of immunotherapy in recent onset Type 1 diabetes of man. In this communication we report our experience with short courses of prednisone and antithymocyte globulin (ATGAM) plus prednisone. Prednisone characteristically suppressed Ia positive T lymphocytes into the normal range, but had no long-lasting effect on T-cell phenotype. ATGAM plus prednisone markedly decreased the ratio of T4/T8 ("helper"/"suppressor-cytotoxic") positive T lymphocytes, and this remained suppressed for months. ATGAM treated patients had lower HbA1c on a lower dose of insulin 100 or more days following immune therapy (with 4 out of 5 patients requiring less than 0.2 U/Kg insulin/day). Two patients in the ATGAM treated group did not require insulin for more than 8 months; during remission they had normal fasting blood glucose values, but with abnormal glucose tolerance on oral glucose tolerance testing. Severe, though transient, thrombocytopenia was observed in 2 patients on ATGAM therapy which outweighed its clinical effects. Topics: Adolescent; Adult; Antilymphocyte Serum; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Humans; Hypoglycemia; Immunotherapy; Male; Prednisone; T-Lymphocytes; Thrombocytopenia; Time Factors | 1985 |
Immunoreactive gastric inhibitory polypeptide response to a meal during the first eighteen months after diagnosis of type 1 (insulin dependent) diabetes mellitus.
The changes in plasma concentrations of immunoreactive gastric inhibitory polypeptide (IR-GIP) in response to a standard meal were examined in 21 normal subjects and 15 Type 1 (insulin dependent) diabetic patients 7 days, 14 days, and 3, 6, 9, 12, and 18 months after time of diagnosis. During the first 4 tests significantly lower plasma IR-GIP concentrations were found in the diabetic patients after the standard meal. At 9 months and during the remaining tests there was no difference in IR-GIP concentrations between the diabetic and the normal subjects. The IR-GIP response was normalized faster if the diabetic patients were treated with initial short term intensive insulin therapy than if they were treated conventionally with 1 or 2 daily injections of insulin. beta-Cell function, evaluated by the C-peptide response to the meal, increased significantly during the first 3 months. After 3 months maximal beta-cell function was found while the corresponding IR-GIP responses were significantly lower than those of the normal subjects. Thereafter beta-cell function declined gradually and significantly, coinciding with the normalization of the IR-GIP response. No individual covariation between IR-GIP and beta-cell function during the 18 months was found in any patient. The IR-GIP response to a meal was diminished at the onset of Type 1 (insulin dependent) diabetes mellitus. After the start of insulin therapy the response improved, perhaps as a function of the quality of metabolic control, and within a year it was comparable to that of normal subjects. Lack of endogenous GIP therefore does not explain the diminished beta-cell function in Type 1 diabetes a few months after onset of the disease. No causal relationship between the changes in beta-cell function and IR-GIP during the first 18 months after the onset of the disease seems to exist. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Eating; Fasting; Female; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Humans; Immunoassay; Insulin; Insulin Secretion; Islets of Langerhans; Male; Time Factors | 1985 |
The pathophysiology of experimental insulin-deficient diabetes in the monkey. Implications for pancreatic transplantation.
In an 11-year study of experimental insulin-deficient diabetes (IDDM) induced in rhesus monkeys by streptozotocin or total pancreatectomy, the authors have found that pathophysiologic changes occur in eye and kidney, which closely resemble the early stages of human insulin deficient diabetes mellitus (IDDM). In addition, morphologic changes of thickening of glomerular capillary basement membrane and expansion of mesangial matrix (by light microscopy) appear within 3 years of onset of hyperglycemia. However, progression to irreversible complications of advanced diabetic nephropathy or proliferative retinopathy, have not occurred. This animal model resembles human disease in that the animals tend to become ketotic unless maintained with exogenous insulin; C-peptide production is low to absent, and large amounts of glycosylated hemoglobin develop within a month of onset. The monkeys differ from humans in the absence of hypertension and hyperlipidemia. The authors suggest that the abnormalities in basement membrane form and function caused by hyperglycemia form the necessary background upon which other factors, such as hypertension and hyperlipidemia, then act to cause irreversible complications. The role of pancreatic transplantation is in prevention of these background changes. Topics: Animals; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Retinopathy; Eye; Glycated Hemoglobin; Hypertrophy; Kidney; Macaca mulatta; Pancreas Transplantation; Proteinuria | 1985 |
Effect of insulin antibodies on insulin pharmacokinetics and glucose utilization in insulin-dependent diabetic patients.
To determine the impact of insulin-binding antibodies on total (TIRI) and free insulin (FIRI) as well as on insulin sensitivity, 10 insulin-dependent diabetic patients (IDDM) with poststimulatory C-peptide less than 100 pmol/L and an insulin binding capacity (IBC) between less than 1 and 294 micrograms/L serum were studied during and after a 1-h nonprimed, constant-rate insulin infusion (study 1: 0.057 U/kg body wt, study 2: 0.286 U/kg body wt). Euglycemia was maintained by variable glucose infusion. Control studies were performed in 5 healthy subjects. Basal TIRI (mU/L) was lowest in healthy subjects (16 +/- 1 [SE]) and elevated in diabetic patients (IBC less than 25 micrograms/L: 72 +/- 11, IBC greater than 25 micrograms/L: 1772 +/- 842), whereas serum concentrations of FIRI were considerably smaller but still two- to threefold greater (P less than 0.01) in the patients than in healthy subjects (13 +/- 1). After intravenous (i.v.) insulin administration, almost identical increments in serum TIRI were seen in healthy subjects and in diabetic patients with low IBC (less than 25 micrograms/L), whereas those with high IBC (greater than 25 micrograms/L) had a heterogeneous response.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Half-Life; Humans; Infusions, Parenteral; Insulin; Insulin Antibodies; Kinetics; Male; Middle Aged | 1985 |
Residual insulin secretion in insulin dependent diabetes mellitus.
The residual insulin secretory capacity of 244 children with insulin dependent diabetes mellitus was determined by measurement of their 24 hour urinary C peptide excretion. An inverse linear relation was found between the residual B cell secretion and the duration of diabetes. The age at onset of diabetes did not affect the residual B cell function significantly. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Infant; Insulin; Insulin Secretion; Male; Time Factors | 1985 |
Validity of WHO criteria for classification of newly diagnosed diabetics.
In order to assess the validity of WHO criteria for the discrimination between Type I and Type II diabetes a cross-sectiona clinical study was performed in 84 normweight newly diagnosed diabetics with a mean age of 22 years. Taking into consideration clinical and biochemical characteristics of the carbohydrate and fat metabolism, the therapeutic requirement to maintain euglycemic metabolic control, the residual beta-cell function, the HLA phenotype and islet cell antibodies (ICA, ICSA) it could be shown that none of the tested criteria has the ability to distinguish between the types with absolute certainty. As shown by the frequency of the different markers in relation to the therapeutic requirements for euglycemic metabolic control as well as by the correlation analysis between the variables the discriminating validity of the markers decreased in the following sequence: diabetes associated HLA phenotype, residual beta-cell function, proneness to ketosis, age at onset, relative body weight. Neither the characteristics of the carbohydrate and fat metabolism nor the presence of islet cell antibodies contributed much to the differentiation between insulin-dependent and noninsulin-dependent diabetes. Topics: Adolescent; Adult; Aged; Antibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Evaluation Studies as Topic; Fasting; Female; HLA Antigens; Humans; Islets of Langerhans; Male; Middle Aged; Phenotype; Time Factors; World Health Organization | 1985 |
Serum magnesium in insulin-dependent diabetics and healthy subjects in relation to insulin secretion and glycemia during glucose-glucagon test.
In order to investigate the influence of insulin secretion on serum magnesium concentrations 33 insulin-dependent diabetics and 10 control subjects were studied. The residual insulin secretion (RIS) was investigated by measurement of human C-peptide (HCP) before and after stimulation during on OGTT (1.75 mg/kg)-glucagon (i.v. 0.1 mg glucagon/kg)-test.. Certain RIS existed in 11 insulin-dependent diabetics, 12 were without any RIS (uncertain RIS in 10 patients). Glucose tolerance and daily glycemia differed significantly among the two groups. However, all diabetics were far from euglycemia, (3.3-9.3 mmol/l): Fasting plasma glucose 12.0 +/- 0.9 (certain RIS), 15.0 +/- 0.8 (no RIS), 13.9 +/- 1.8 (uncertain RIS). Serum magnesium was significantly lower in all diabetics, both before and during the test. There was no change during the OGTT-glucagon-test and no difference among the three groups of insulin-dependent diabetics. So, we conclude that a small RIS in our longterm insulin-dependent diabetics has no influence on the behaviour of serum magnesium. But, magnesium depletion can influence coronary blood flow, blood clotting, and atherogenesis. Therefore, it should be necessary to pay more attention to the hypomagnesemia in insulin-dependent diabetics. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Glucose; Humans; Insulin; Insulin Secretion; Magnesium | 1985 |
Meal-stimulated C-peptide and insulin antibodies in type I diabetic subjects and their nondiabetic siblings characterized by HLA-DR antigens.
We studied serum C-peptide (CP) response 90 min after a breakfast meal and insulin antibody titers in 171 type I diabetic (IDDM) patients and 272 of their nondiabetic siblings from 169 unrelated families. HLA typing was performed in all participants. In IDDM patients, there was a decline in CP response with increased duration of disease. CP responses of greater than or equal to 1.8 ng/ml were seen significantly less often in patients who were less than 10 yr old at the time of diagnosis of IDDM than in patients who were greater than 10 yr old at the time of diagnosis (8% versus 21%, P less than 0.05). More patients with HLA-DR4 had a CP response greater than or equal to 1.8 ng/ml than did patients who lacked this antigen whether duration of IDDM was less than 10 yr (30% versus 18%, P greater than 0.05) or greater than or equal to 10 yr (15% versus 0%, P less than 0.05). Mean C-peptide was also higher in HLA-DR4-positive patients compared with HLA-DR4-negative patients both when duration of disease was less than 10 yr (1.7 +/- 1.9 versus 1.4 +/- 1.0, P less than 0.01) and greater than or equal to 10 yr (1.2 +/- 1.5 versus 1.0 +/- 0.4, P less than 0.0001). Insulin antibody binding was slightly higher in patients with HLA-DR4 compared with patients lacking this antigen (5.96 +/- 7.20 versus 4.89 +/- 4.74, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Age Factors; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Eating; Female; Haploidy; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Insulin Antibodies; Islets of Langerhans; Male; Time Factors | 1985 |
Near-total pancreatectomy for hyperinsulinism. Spontaneous remission of resultant diabetes.
Persistent hyperinsulinism in the newborn may warrant surgical intervention to prevent neurologic sequelae. Subtotal pancreatectomy may not be adequate, necessitating near-total pancreatectomy with subsequent development of diabetes mellitus. We report an infant with hyperinsulinemic hypoglycemia who underwent near-total pancreatectomy. The postoperative period was characterized by insulin-dependency and extreme insulin sensitivity. Clinical follow-up and C-peptide determinations showed a return of insulin secretory capacity permitting the discontinuation of insulin therapy after five months. This experience reaffirms the potential for a favorable outcome after near-total pancreatectomy in the newborn period for severe hyperinsulinism. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hyperinsulinism; Infant; Infant, Newborn; Insulin; Pancreatectomy; Remission, Spontaneous | 1985 |
Lack of strong association between residual human C-peptide secretion and islet cell antibodies, complement-dependent antibody-mediated cytotoxicity, and HLA antigens in newly diagnosed type I diabetics.
Topics: Adolescent; Adult; Aged; Antibody-Dependent Cell Cytotoxicity; Autoantibodies; C-Peptide; Child; Child, Preschool; Complement System Proteins; Diabetes Mellitus, Type 1; Gene Frequency; HLA Antigens; Humans; Islets of Langerhans; Middle Aged | 1985 |
Enhanced glycemic responsiveness to epinephrine in insulin-dependent diabetes mellitus is the result of the inability to secrete insulin. Augmented insulin secretion normally limits the glycemic, but not the lipolytic or ketogenic, response to epinephrine
To determine if the enhanced glycemic response to epinephrine in patients with insulin-dependent diabetes mellitus (IDDM) is the result of increased adrenergic sensitivity per se, increased glucagon secretion, decreased insulin secretion, or a combination of these, plasma epinephrine concentration-response curves were determined in insulin-infused (initially euglycemic) patients with IDDM and nondiabetic subjects on two occasions: once when insulin and glucagon were free to change (control study), and again when insulin and glucagon were held constant (islet clamp study). During the control study, plasma C-peptide doubled, and glucagon did not change in the nondiabetic subjects, whereas plasma C-peptide did not change but glucagon increased in the patients. The patients with IDDM exhibited threefold greater increments in plasma glucose, largely the result of greater increments in glucose production. This enhanced glycemic response was apparent with 30-min increments in epinephrine to plasma concentrations as low as 100-200 pg/ml, levels that occur commonly under physiologic conditions. During the islet clamp study (somatostatin infusion with insulin and glucagon replacement at fixed rates), the heightened glycemic response was unaltered in the patients with IDDM, but the nondiabetic subjects exhibited an enhanced glycemic response to epinephrine indistinguishable from that of patients with IDDM. In contrast, the FFA, glycerol, and beta-hydroxybutyrate responses were unaltered. Thus, we conclude the following: Short, physiologic increments in plasma epinephrine cause greater increments in plasma glucose in patients with IDDM than in nondiabetic subjects, a finding likely to be relevant to glycemic control during the daily lives of such patients as well as during the stress of intercurrent illness. Enhanced glycemic responsiveness of patients with IDDM to epinephrine is not the result of increased sensitivity of adrenergic receptor-effector mechanisms per se nor of their increased glucagon secretory response; rather, it is the result of their inability to augment insulin secretion. Augmented insulin secretion, albeit restrained, normally limits the glycemic response, but not the lipolytic or ketogenic responses, to epinephrine in humans. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Fatty Acids, Nonesterified; Female; Glycerol; Humans; Hydroxybutyrates; Insulin; Ketosis; Lactates; Lactic Acid; Lipid Mobilization; Male; Norepinephrine | 1985 |
Growth hormone hyperproduction inducing some of the vicious circles in diabetes mellitus.
Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Growth Hormone; Humans; Hypophysectomy; Insulin; Rats | 1985 |
Comparison of insulin-mediated and glucose-mediated glucose disposal in patients with insulin-dependent diabetes mellitus and in nondiabetic subjects.
To determine whether glucose-mediated as well as insulin-mediated regulation of glucose utilization and glucose production is impaired in patients with insulin-dependent diabetes mellitus (IDDM), six nonobese, diabetic patients and seven age-, sex-, and weight-matched nondiabetic subjects were studied. Despite slightly higher free insulin concentrations in the diabetic patients than in the nondiabetic subjects during 0.2 mU/kg X min (22 +/- 3 versus 15 +/- 2 microU/ml) and 1.0 mU/kg X min (98 +/- 10 versus 75 microU/ml) insulin infusions, glucose utilization at plasma glucose concentrations of 95, 135, and 175 mg/dl was lower in the diabetic patients than in the nondiabetic subjects. The increment in glucose utilization per increment in plasma glucose (i.e., slope) in the diabetic and nondiabetic subjects, respectively, did not differ significantly during either the 0.2 (1.7 +/- 1.3 versus 1.4 +/- 0.5 dl/kg X min) or 1.0 (4.4 +/- 1.1 versus 6.2 +/- 1.0 dl/kg X min) mU/kg X min insulin infusions, although they tended to be higher in the nondiabetic subjects during the latter infusion. Thus, although stimulation of glucose utilization by insulin is impaired in patients with IDDM, the ability of an increase in glucose concentration to increase glucose utilization does not appear to differ from that present in nondiabetic subjects, at insulin concentrations in the low physiologic range. Whether differences exist in the high physiologic range remains to be determined. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Glucose; Growth Hormone; Humans; Hydrocortisone; Insulin; Male; Norepinephrine | 1985 |
C-peptide measurement in the differentiation of type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus.
To determine whether individual subjects with Type 1 (insulin-dependent) diabetes or Type 2 (non-insulin-dependent) diabetes, who are treated with insulin, could be reliably distinguished, C-peptide concentrations and urinary C-peptide excretion were measured in 10 Caucasoids and 10 Pima Indians. All the subjects had developed diabetes before 21 years of age and were receiving insulin treatment. Fasting C-peptide concentrations were significantly higher in the Pima Indians (0.73 +/- 0.17 versus 0.02 +/- 0.01 nmol/l in Caucasoids; p less than 0.001), but there were slight overlaps in individual values. Urinary C-peptide excretion, an index of 24-h-insulin excretion, was also higher in the Pima Indian group (27.6 +/- 1.85 versus 0.72 +/- 0.18 pmol/min in Caucasoids; p less than 0.001) and there was no overlap in the individual values between the groups. The Pima Indians with early onset diabetes have been previously shown to have Type 2 diabetes, and the Caucasoids with an early onset are most likely to have Type 1 diabetes. These results suggest that distinction between these two major types of diabetes can be made effectively by using C-peptide measurements provided that overt renal disease is absent. This differentiation between insulin-treated patients will be useful for a variety of research applications and possibly in making clinical management decisions. Topics: Adolescent; Adult; Age Factors; Arginine; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Glucose Tolerance Test; Humans; Indians, North American; Insulin; Male; White People | 1985 |
Hyperalaninaemia is an early feature of diabetes secondary to total pancreatectomy.
High levels of gluconeogenic precursors have been reported in patients with long-term diabetes secondary to total pancreatectomy. In the present study, blood concentrations of alanine, lactate and pyruvate were measured in six patients undergoing total pancreatectomy and in nine control subjects undergoing major abdominal surgery. To exclude the simple effect of lack of insulin and hyperglycaemia in the development of hyperalaninaemia following total pancreatectomy, three pancreatectomized patients and five control subjects underwent surgical operation while connected to an artificial pancreas. Blood concentration of alanine was constant in the control subjects during surgery (182 +/- 20 and 243 +/- 31 mumol/l with and without the artificial pancreas, respectively). In pancreatectomized patients basal blood alanine levels were similar to those in control subjects. Blood alanine level rose quickly after removal of the pancreas from 182 +/- 24 to 285 +/- 15 mumol/1 (p less than 0.05) in the patients connected to the artificial pancreas, and from 198 +/- 17 to 395 +/- 47 mumol/1 (p less than 0.05) in patients undergoing total pancreatectomy without artificial pancreas. These values were higher than those observed in the control subjects at the end of the operation (192 +/- 22 and 230 +/- 45 mumol/l with and without artificial pancreas, respectively.) Basal and intraoperative blood concentrations of lactate and pyruvate were similar in pancreatectomized patients and control subjects. Topics: Adenocarcinoma; Adult; Aged; Alanine; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Insulin Infusion Systems; Intraoperative Period; Lactates; Male; Middle Aged; Pancreatectomy; Pancreatic Neoplasms; Pyruvates | 1985 |
Correlates of insulin antibodies in newly diagnosed children with insulin-dependent diabetes before insulin therapy.
Insulin antibodies, as measured by plasma radiolabeled insulin-binding capacity, were determined in 124 newly diagnosed insulin-dependent diabetic (IDDM) children before and after 1, 3, and 5 days of insulin therapy. Controls were 35 nondiabetic children with plasma insulin binding capacity of 1.0 +/- 0.7%. The patients were divided into three groups according to their plasma insulin-binding capacity. Group 1 (N = 79) had binding within two standard deviations (SD) of the control mean, group 2 (N = 20) had insulin binding 2-6 SD above controls, and group 3 (N = 25) showed insulin-binding capacity of more than 6 SD above the control mean. After exogenous insulin therapy, plasma 125I-insulin-binding capacity dropped significantly in both groups 2 and 3, concurrent with significant increases in plasma insulin levels. The three groups differed from each other in that patients in group 3 were significantly younger than in the other groups and clinically seemed to be more severely dehydrated, as reflected in their higher levels of serum urea nitrogen, plasma glucose, potassium, and elevated pulse rate. The three groups did not differ in respect to sex, HLA-DR antigens, Coxsackie-B antibody titers, islet cell cytoplasmic antibodies, immunoglobulin level, and C-peptide levels. Only two of 446 siblings of IDDM children showed elevated insulin binding, one of whom developed IDDM 6 wk later. The presence of an insulin-binding substance probably representing insulin antibodies in some cases of newly diagnosed IDDM suggests that autoimmunity in this disorder is not limited to the B-cell membrane and cytoplasm and lends further support to the heterogeneity of IDDM. Topics: Adolescent; Antibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Infant; Insulin; Islets of Langerhans; Male | 1985 |
Triad of markers for identifying children at high risk of developing insulin-dependent diabetes mellitus.
A longitudinal investigation was conducted from 1977 to 1984 on 178 families in which one or more of the children had insulin-dependent diabetes mellitus. Of 351 nondiabetic sibs followed up for an average of 54 months, ten have, thus far, become diabetic. Eight sibs were HLA identical to their diabetic proband and nine had HLA-DR3 and/or HLA-DR4. Islet cell surface antibody and islet cell cytoplasmic antibody were found from two to 74 months before the onset of clinical diabetes in 100% and 90%, respectively, of the children. A decrease in insulin secretion was observed in all of these children on entry into the study and was detected in the absence of elevated plasma glucose concentrations. The data suggest that the triad of HLA identity, pancreatic islet cell antibodies, and depressed insulin secretion identifies those sibs who are at high risk of developing insulin-dependent diabetes mellitus. Topics: Adolescent; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Glycated Hemoglobin; HLA Antigens; Humans; Infant; Insulin; Insulin Secretion; Longitudinal Studies; Male; Risk | 1985 |
Characterization of insulin resistance in type I diabetes.
Insulin sensitivity was assessed using the euglycaemic clamp technique in eight type I diabetic patients (after overnight blood glucose normalization with an artificial pancreas) and in six healthy subjects. Basal insulin concentrations were higher in diabetic patients (25 +/- 4 microU/ml) than in control subjects (17 +/- 1 microU/ml; P less than 0.05). Insulin infusion of 0.5, 1.0, 2.0 and 5.0 mU/kg per min during subsequent 2-h periods resulted in similar mean steady-state insulin concentrations in both groups. The mean dextrose requirements during the last 40 min of each period were nevertheless decreased in diabetic patients (1.6 +/- 0.5, 3.5 +/- 0.8, 6.5 +/- 0.7, 10.2 +/- 0.7 mg/kg per min) as compared with control subjects (4.7 +/- 0.3, 8.2 +/- 0.9, 10.2 +/- 0.9, 12.4 +/- 0.9 mg/kg per min). At low insulin concentrations dextrose requirements were diminished in all diabetic subjects. At the highest insulin levels, individual dose-response curves from only four patients were within the normal range. Under basal conditions, the monocyte receptor number was significantly reduced in diabetic patients (17,500 +/- 2,800 sites/cell) as compared with control subjects (26,700 +/- 2,500 sites/cell; P less than 0.05), whereas there were no differences regarding empty site affinities. Receptor data did not differ in patients with normal and decreased maximal dextrose requirements. Insulin resistance is apparently a common feature of type I diabetes at serum insulin concentrations of approximately 100 microU/ml. Normalization of the insulin effect by higher insulin concentrations is not possible in all patients. Insulin antibodies at concentrations observed in this study (less than 0.16 mU/ml) do not contribute significantly to insulin resistance; receptor and postreceptor defects are possibly more important. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Female; Glucose; Humans; Infusions, Parenteral; Insulin; Insulin Resistance; Male; Middle Aged | 1985 |
New probes to study insulin resistance in men; futile cycle and glucose turnover.
Insulin resistance has been measured in man by nonsteady state tracer methodology. Increase in overall glucose utilization and suppression of glucose production was measured when hyperglycemia was achieved either by infusing glucagon or glucose. With the first method, insulin resistance was assessed in obese man and in lean hypertriglyceridemic patients. With the second method, insulin resistance was assessed in lean mild type II diabetics. These methodologies can only assess deficiences in overall glucose utilization and glucose production, but cannot delineate the defect in glucose uptake by the liver. However, if a given metabolic event is essentially characteristic of only one organ, metabolic abnormalities specific to that organ can be detected in vivo provided there is a probe specific to that metabolic pathway. Therefore, in lean mild type II diabetics the liver glucose futile cycle was assessed by a double tracer method. Previously it was shown that liver glucose futile cycling is increased in diabetic dogs. In healthy control subjects in basal state and during glucose infusion, the futile cycle could not be detected, but it represented a major part of glucose metabolism in liver of type II diabetics. It appears, therefore, that most of the glucose taken up by the liver during the glucose challenge in diabetics reenters the blood stream without being oxidized or polymerized. On the basis of these studies, it was concluded that excessive hyperglycemia in the diabetics during glucose infusion is due to a decrease in irreversible glucose uptake (impaired phosphorylation and futile cycling) and to a decrease in suppression of glucose production. The relative contribution of the liver and periphery to hyperglycemia seems to be almost equivalent. The mechanism behind the increased glucose cycle activity is not clear. It may be due to a relative decrease of glycogen synthase or increase in glucose-6-phosphatase or both. These observations in mild lean type II diabetics may have implications also in some other types of diabetes, since we have observed that futile cycling is even more marked in obese type II diabetics and that it could account in part for the diabetogenic effect of growth hormone in acromegalics. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose; Homeostasis; Humans; Insulin; Insulin Resistance; Obesity; Reference Values | 1985 |
Insulin secretory capacity in Singapore diabetic subjects.
The determination of serum C-peptide has been found to be a sensitive indicator of endogenous insulin secretion, and serves to define diabetic patients who require insulin therapy i.e., insulin-dependent (Type I, IDDM) and those non-insulin dependent (Type II, NIDDM). The aim of our study is to establish the types of diabetes mellitus with C-peptide measurement in a group of diabetic subjects on different modes of therapy. Eighty-eight diabetic patients (60 males, 28 females) were studied. Thirty-four were on insulin (age 40 +/- 2 years; means +/- SEM), 35 on oral agents (54 +/- 1 years), and 19 on diet alone (46 +/- 3 years). Twenty healthy subjects (10 males, 10 females) serve as normal controls (37 +/- 3 years). Blood samples for serum C-peptide and blood glucose estimations were obtained after an overnight fast and one hour after a 75 grams oral glucose load. Fasting C-peptide levels obtained for the various groups were: 0.62 +/- 0.07 (nmol/L, means +/- SEM) (normal), 0.16 +/- 0.02 (insulin), 0.79 +/- 0.06 (oral), 2.15 +/- 0.15 (diet). The C-peptide values after oral glucose were 1.80 +/- 0.20 (normal), 0.23 +/- 0.05 (insulin), 1.72 +/- 0.02 (oral), 2.15 +/- 0.15 (diet). Both the fasting and post-glucose C-peptide concentrations were significantly lower (p less than 0.001) in the insulin group compared to the normals, whereas values for the diet and oral groups were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Singapore | 1985 |
Islet cell antibodies in insulin-dependent (type 1) diabetic children treated with plasmapheresis.
Plasma levels of islet cell cytoplasmic and cytotoxic antibodies were determined in 10 children with insulin-dependent diabetes mellitus (IDDM) treated with plasmapheresis shortly after diagnosis, and in 9 children with IDDM treated by conventional means alone. Islet cell cytoplasmic antibody (ICA) titers were determined by indirect immunofluorescence using unfixed sections of human pancreas, and islet cell cytotoxic antibody levels were determined in a complement-dependent antibody-mediated cytotoxicity (C'AMC) assay using a human fetal cloned insulin-producing cell line (JHPI-1) as target. Before plasmapheresis, ICA was present in 7 out of 10 children and C'AMC was positive in 4. Four successive treatments with plasmapheresis did not consistently decrease plasma levels of ICA or C'AMC. ICA was present in 15 out of the total 19 children at diagnosis, and titers of ICA decreased in 12 out of 15 subjects by at least 1 degree of dilution (1:3) at 18-30 months follow-up, whether or not they had been treated with plasmapheresis; C'AMC was positive in 6 out of the 18 children at diagnosis and decreased in 2 out of 6. Plasma levels of C-peptide did not differ at diagnosis but remained higher in the plasmapheresis treated diabetic children at 3 and 18-30 months follow-up. Neither ICA titers nor C'AMC levels correlated with plasma C-peptide responses at 18-30 months. It is concluded that plasmapheresis decreases ICA and C'AMC but is followed rapidly by a rebound effect, and does not affect the rates at which these islet cell antibodies decrease with increasing duration of IDDM. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Islets of Langerhans; Male; Plasmapheresis | 1985 |
Pathophysiological interrelations of obesity, impaired glucose tolerance, and arterial hypertension.
There is a large amount of epidemiological and clinical evidence for associations among obesity, impaired glucose tolerance, and arterial hypertension; nevertheless, the pathophysiological mechanisms underlying these associations have not yet been elucidated. In this article, some working hypotheses are discussed, and original data are presented from two studies focusing on these pathophysiological interrelations. A case-control study of obese normotensive and hypertensive patients, matched for sex, age, and degree of overweight, has shown that obese patients with associated arterial hypertension have higher fasting serum insulin levels and reduced glucose tolerance compared with their normotensive peers. A second study compared subjects with impaired glucose tolerance with a control group of clinically healthy individuals of comparable sex, age, and body mass index, and it revealed that impaired glucose tolerance is associated with significantly higher blood pressure levels, independent of body weight. The results of the two studies together suggest that the association between hypertension and impaired glucose tolerance is independent of overweight; they also give some support to the hypothesis that hyperinsulinemia may contribute to the development of high blood pressure in obese patients. Topics: Adult; Blood Glucose; Blood Pressure; C-Peptide; Coronary Disease; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Hypertension; Insulin; Male; Middle Aged; Obesity; Risk | 1985 |
C-peptide determination in the choice of treatment in diabetes mellitus.
The predictive value of the intravenous glucagon test in assessing the requirement of insulin therapy in diabetes mellitus was evaluated in 105 adult diabetics. Basal and stimulated C-peptide concentrations and increments of C-peptide concentration were examined separately among newly and previously diagnosed diabetics. The poststimulatory C-peptide concentration of 0.6 nmol/l (Novo, antibody M 1230) proved to be the most reliable basis for the choice of therapy. Adequate therapy could have been assessed in 70 cases (67%) without glucagon stimulation. To derive maximal information of plasma C-peptide concentrations, a biphasic scheme of the use for C-peptide determinations and glucagon stimulation is presented. Basal and stimulated C-peptide levels of insulin-requiring diabetics correlated negatively with the duration of diabetes but they did not correlate with the relative body weights. Basal and stimulated C-peptide levels of non-insulin-requiring diabetics did not correlate with the duration of diabetes, but they correlated positively with the relative body weights. Topics: Adolescent; Adult; Aged; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucagon; Humans; Insulin; Middle Aged | 1985 |
[Treatment of type I diabetes mellitus with biosynthetic human insulin].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Antibodies; Male; Middle Aged; Recombinant Proteins; Time Factors | 1985 |
Prevalence of macro- and microvascular disease as related to glycosylated hemoglobin in type I and II diabetic subjects. An epidemiologic study in Denmark.
The prevalence of macro- and microvascular disease and the distribution of glycosylated hemoglobin (Hb A1) were assessed in a representative Danish diabetes population living on the island of Falster with a population of 44.498 inhabitants. The diabetes population consisted of 533 diabetics of whom 166 were insulin-dependent (type I) and 367 non-insulin-dependent (type II). Among the 533 diabetics macrovascular complications as evidenced by myocardial infarction, gangrene or amputations and cerebrovascular catastrophes were present in 8%, 5% and 7%, respectively, while microvascular disease as evidenced by diabetic retinopathy was present in 53% of the cases. Multilogistic analysis showed no relationship between the macrovascular complications and the level of Hb A1, whereas there was a highly significant correlation between the level of Hb A1 and the presence of retinopathy in both patients with type I (P less than 0.01) and type II diabetes (P less than 0.001). The results emphasize the contention that the development of microvascular disease depends on the quality of blood glucose control while that of macrovascular disease seems unrelated to long-term hyperglycemia. Topics: Blood Glucose; C-Peptide; Denmark; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Glycated Hemoglobin; Humans; Insulin; Male; Time Factors | 1985 |
Plasma lipoproteins and lipoprotein lipase in young diabetics with and without ketonuria.
Plasma lipoprotein and lipoprotein lipase activity have been evaluated in young diabetics with and without ketonuria and in healthy controls of the same age. Fifteen (age range 7-23 years) newly detected diabetics (8 with ketonuria, 7 non ketonuric) have been examined before starting the treatment. Five healthy medical students (age range 19-21 years) have also been studied. Both ketotic and non ketotic patients showed an impaired insulin and C-peptide response to the glucose load in comparison to controls. Ketotic patients had low lipoprotein lipase activity (p less than 0.01) and high density lipoprotein (p less than 0.01); total plasma Triglycerides and VLDL Triglyceride and Cholesterol were higher than in controls. Plasma Triglyceride and VLDL Triglyceride and Cholesterol were inversely related to lipoprotein lipase activity. Low lipoprotein lipase activity, from adipose tissue and muscle, has been found to be associated with hypertriglyceridemia and reduced HDL Cholesterol in young diabetic patients with ketonuria. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Hyperlipidemias; Insulin; Ketone Bodies; Lipoprotein Lipase; Lipoproteins; Male | 1985 |
Increased reduction in fasting C-peptide is associated with islet cell antibodies in type 1 (insulin-dependent) diabetic patients.
A cohort of 82 patients with Type 1 (insulin-dependent) diabetes was followed prospectively for 24 months, and 54 of them for 30 months, to study the relationship between fasting levels of immunoreactive C-peptide and titres of islet cell antibodies. After diagnosis, fasting C-peptide rose temporarily for 1-6 months of insulin therapy and declined continuously thereafter. While islet cell antibodies were present among 55% of the newly diagnosed patients, only 31% remained positive at 30 months. Their antibody titres decreased from 1:81 at diagnosis to 1:3. Only 3 patients (4%) who were islet cell antibody negative at diagnosis became positive later. The median C-peptide values among the persistently islet cell antibody positive patients decreased from 0.11 pmol/ml at 18 months, to 0.09 pmol/ml at 24 months, to 0.06 pmol/ml at 30 months compared to 0.18 (p = 0.04), 0.15 (p = 0.05) and 0.16 (p less than 0.003) pmol/ml, respectively, for the islet cell antibody negative patients. The median slope for the latter was -0.09 compared to -0.19 for the islet cell antibody positive patients (p = 0.01). These differences were reflected in increasing dosages of insulin, since patients remaining antibody-positive for 30 months were given 1.3-1.4 times more insulin (p = 0.01-0.004) than the antibody negative patients. This study demonstrates that islet cell antibodies may be a useful marker for predicting an increased rate by which endogenous B cell function is lost in Type 1 diabetes. Topics: Adolescent; Adult; Aged; Autoantibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fasting; Female; Humans; Infant; Insulin; Islets of Langerhans; Male; Middle Aged; Time Factors | 1985 |
Beta-cell function and diabetic control in insulin dependent diabetes melletus.
Beta-cell function, as evaluated from plasma C-peptide measurements, is found in all insulin dependent diabetic patients the first months of disease and in about 15% of patients with more than 15 years of treatment. The beta-cells are capable of modulating their secretory activity in response to changes in blood glucose. Even a minimal residual insulin secretion is of metabolic significance. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Islets of Langerhans | 1985 |
Gastric inhibitory polypeptide (GIP): a therapeutic possibility?
Topics: Animals; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Gastric Inhibitory Polypeptide; Glucose; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Swine | 1985 |
Serum free C-peptide response to oral glucose loading as a parameter for the monitoring of pancreatic B-cell function in diabetic patients.
As a parameter for evaluating pancreatic B-cell function, the accuracy of measuring serum free C-peptide immunoreactivity (CPR) was compared with that of measuring plasma immunoreactive insulin (IRI) and urine CPR in diabetic patients during a 100 g oral glucose tolerance test. In 25 non-obese patients receiving oral hypoglycemic agent or diet treatment alone, a positive correlation between the sum of serum free CPR (sigma serum free CPR) and the sum of plasma IRI (sigma plasma IRI) was noted (r = 0.68, P less than 0.001). However, the sum of blood glucose values was found to be negatively correlated to sigma free CPR (r = -0.56, P less than 0.0025), but not to sigma plasma IRI (r = -0.25, NS). In 23 patients receiving diet, oral hypoglycemic agent or insulin treatment, a positive correlation between sigma serum free CPR and urine CPR was noted (r = 0.75, P less than 0.001). However, no significant correlation was found when only insulin-treated patients were investigated (r = 0.37, NS, n = 17). In addition, patients with insulin-dependent diabetes mellitus and non-insulin-dependent diabetes mellitus were better differentiated by measuring sigma serum free CPR than urine CPR. Thus, we concluded that the measurement of serum free CPR during OGTT provides an extremely valuable method for monitoring pancreatic B-cell function in diabetic patients, whether they are receiving insulin treatment or not. Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Islets of Langerhans; Middle Aged | 1985 |
A comparison of serum C-peptide response to intravenous glucagon, and urine C-peptide, as indexes of insulin dependence.
Serum C-peptide (SCPR) at fasting and after intravenous injection of glucagon was evaluated in diabetic patients with various degrees of insulin dependence, and compared with 24 h urine C-peptide (UCPR). Fasting SCPR did not differ between healthy subjects and sulfonylurea-treated patients (SU) who were considered to have definite non-insulin-dependent diabetes (NIDDM); but was significantly lower in patients with insulin-dependent diabetes (IDDM) (0.24 +/- 0.10 ng/ml in IDDM vs. 1.43 +/- 0.61 ng/ml in SU, P less than 0.001). SCPR reached a peak at 6 min after glucagon injection, except for the IDDM group. The SCPR response at 6 min after 1 mg glucagon injection was significantly lower in the SU (NIDDM) group than in the normal group (2.86 +/- 1.21 v. 4.69 +/- 1.47 ng/ml, P less than 0.001). In the IDDM group, there was no increase of SCPR after glucagon injection. Among diabetic patients, SCPR response to glucagon correlated positively to the amounts of UCPR (P less than 0.001). By analysis of the distribution patterns of SCPR response to intravenous glucagon, SCPR of 1.0 ng/ml and the increment of SCPR of 0.5 ng/ml at 6 min are to be used as cut-off points to differentiate IDDM and NIDDM. These values correspond roughly to the UCPR values below 20 micrograms/day and above 30 micrograms/day, which we previously proposed as indexes to differentiate insulin-dependent and non-insulin-dependent diabetes. Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Glucagon; Humans; Insulin; Kinetics; Sulfonylurea Compounds | 1985 |
Serum fructosamine concentration as measure of blood glucose control in type I (insulin dependent) diabetes mellitus.
Serum fructosamine activity was studied in 42 patients with type I (insulin dependent) diabetes mellitus and 30 non-diabetic volunteers as an index of blood glucose control. There was a significant correlation both between fructosamine and glycosylated haemoglobin values (r = 0.82) and between fructosamine and the fasting C peptide concentration (r = -0.81). Test results in 14 of the diabetics reflected the mean plasma glucose concentration calculated from 25 serial estimations in a single 24 hour period (r = 0.75; p less than 0.01) but not the mean amplitude of glycaemic excursion (r = 0.23; p greater than 0.05). Fructosamine concentrations measured in these multiple blood specimens did not change significantly throughout the day (mean coefficient of variation 4.1%) despite wide variability of the respective plasma glucose concentrations (mean coefficient of variation 36.2%). It is concluded that a single random serum sample analysed for fructosamine concentration provides a simple and reliable assessment of glucose homoeostasis in patients with type I diabetes mellitus. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Fructosamine; Glycated Hemoglobin; Hexosamines; Humans; Insulin; Male; Middle Aged; Time Factors | 1985 |
Clinical transplantation of fetal human pancreatic islets.
Fetal human Langerhans islets were isolated from pancreatic tissue of 2 embryos aged 20 and 22 weeks by partial collagenase digestion. The islets were kept in Eagle's medium at 37 degrees C and 5% CO2 for 10 weeks. The insulin production was continuous during this period. The two cultured fetal islet masses were transplanted to a 31-year-old diabetic man and a 58-year-old diabetic woman. They have required insulin treatment for 25 and 30 years, respectively, and have suffered from retinopathy. The transplantations were performed to the liver after tissue typing. In the case of the man the daily insulin requirement was slightly reduced after 4 months of transplantation but later (8th month) the insulin dose was half the original one. Just now (24 months) the insulin dose is on the same level. In the case of the woman the daily insulin requirement was reduced only after 8 months of transplantation. Just now (13 months) her insulin dose is 12 U less than the original one. In both of them the function of the transplanted islets was proved by measurement of serum C-peptide level and by the fundus examination (no progression of retinopathy). Topics: Adult; C-Peptide; Culture Techniques; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Male; Middle Aged | 1985 |
Sulfonylureas in insulin-dependent (type I) diabetes: evidence for an extrapancreatic effect in vivo.
The effect of glibenclamide treatment on insulin-mediated glucose disposal was studied in eight C-peptide-negative type I diabetic patients. The patients were studied twice by the euglycemic insulin clamp technique. One of the two experiments was preceded by glibenclamide treatment at the dose of 5 mg, three times daily for 15 days; half of the patients had the first test before and the second test after sulfonylurea treatment, and vice versa. Insulin was infused for four periods of 2 h each sequentially at 0.5, 1.0, 2.0, and 5.0 mU kg-1 min-1; for each insulin infusion period, the steady state plasma free insulin levels were comparable with or without glibenclamide. The mean +/- SEM plasma glucose concentration was 88 +/- 2 mg/dl in both experiments. The insulin-mediated glucose disposal rate was greater with glibenclamide during the first insulin infusion period (which generated plasma free insulin levels within the physiological range) 2.68 +/- 0.32 mg kg-1 min-1 with glibenclamide vs. 1.97 +/- 0.20 mg kg-1 min-1 without glibenclamide (P less than 0.005). However, glucose disposal rates did not differ in the diabetic patients with or without glibenclamide treatment during the second, third, and fourth insulin infusion periods, which generated plasma free insulin levels in the supraphysiological range. These results provide evidence for an extrapancreatic effect of glibenclamide at low insulin concentrations during euglycemic clamping in patients with insulin-dependent diabetes mellitus. However, this effect was not reflected clinically in either an increased rate of hypoglycemic reactions or decreased insulin needs during the short term period of treatment. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucose; Glyburide; Humans; Hypoglycemic Agents; Infusions, Parenteral; Insulin; Male; Middle Aged; Sulfonylurea Compounds | 1985 |
[Effect of metabolic control on plasma lipids and lipoproteins in insulin-dependent diabetes in children and adolescents].
Plasma triglycerides, total cholesterol, phospholipids, HDL-cholesterol, HDL-phospholipids, apolipoproteins A-I and B, haemoglobin AIc and C-peptide were measured in 113 children and adolescents (49 males and 64 females) with insulin-dependent diabetes. These patients were divided into four groups according to sex and age (more or less than 12 years old) and into three subgroups according to metabolic control. In female adolescents with poor control, triglycerides and apolipoprotein B were increased whereas HDL-cholesterol, HDL-phospholipids and (HDL/LDL + VLDL)-cholesterol were significantly decreased. In poorly-controlled male adolescents, similar changes were observed except for HDL-cholesterol and HDL-phospholipids which were not significantly decreased. In adolescents, haemoglobin AIc correlated directly with triglycerides, total cholesterol, phospholipids, apolipoprotein B and inversely with HDL-cholesterol, HDL-phospholipids and (HDL/LDL + VLDL)-cholesterol. In children aged less than 12 years, no significant change of HDL-cholesterol or apolipoprotein B was observed even in the poorly-controlled group. Topics: Adolescent; Adult; Apolipoprotein A-I; Apolipoproteins A; Apolipoproteins B; C-Peptide; Child; Child, Preschool; Cholesterol; Cholesterol, HDL; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Lipids; Lipoproteins; Lipoproteins, HDL; Male; Phospholipids; Triglycerides | 1985 |
C-peptide response in patients on insulin therapy.
This study was undertaken to document clinical features and presentation of Type I diabetes and to study beta cell response in these patients. It provides data on 30 insulin treated patients. Type I diabetes presents most commonly in the 20-40 year age group. A positive family history in first degree relatives was noted in 40%. The commonest complications were retinopathy (63%) and peripheral neuropathy (53%). Proteinuria (10%), ischaemic heart disease (13%) and peripheral vascular disease (13%) were less common. Three kinds of response to C-peptide were noted: 1) no response 2) blunted response (below the normal range) and 3) peak response to glucose within the low normal range. Group 3 probably represents Type II insulin treated diabetes. There was poor correlation between fasting blood glucose and basal or peak C-peptide response, or with duration or complications of diabetes. C-peptide response may be used to differentiate Type I from Type II diabetes. Topics: Adolescent; Adult; Aged; Antigen-Antibody Reactions; Antigens; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Fasting; Female; Humans; Insulin; Male; Middle Aged; Time Factors | 1985 |
[Pancreas transplantation: status of the problem in experimental and clinical medicine].
Transplantations of pancreas grafts are performed in patients with juvenile onset of diabetes to halt the progression of secondary microangiopathic organ lesions. The treatment of the exocrine secretion of pancreas grafts remains problematic. Duct occlusion seems to be the safest approach but results in fibrosis of the gland. Therefore more recently drainage is directed to a hollow organ, generally performed as pancreaticojejunostomy. New immunosuppressive therapies improved the transplant results. The diagnosis of occurring rejection is difficult since monitoring of plasma glucoses is not very sensitive. Cold storage of grafts in SGF-solution is a reliable preservation procedure. Islet cell transplantation might be a promising alternative technique in the future. Topics: Animals; Blood Glucose; C-Peptide; Cyclosporins; Diabetes Mellitus, Type 1; Duodenum; Graft Rejection; Humans; Immunosuppression Therapy; Insulin; Islets of Langerhans Transplantation; Organ Preservation; Pancreas Transplantation | 1985 |
Urine C-peptide in relation to the degree of insulin dependence in diabetic patients.
Urine C-peptide per 24 h urine (UCPR) was assayed and correlated with the degree of insulin dependence in 324 diabetic patients. The UCPR and UCPR/weight were 74.7 +/- 26.3 micrograms/day and 1.27 +/- 0.36 micrograms/day, kg in healthy subjects, and these values were similar in diet- and sulfonylurea-treated patients. Insulin-dependent diabetics (IDDM) with history of ketosis or ketoacidosis and/or unstable plasma glucose, and patients refractory to sulfonylureas had lower UCPR values (8.5 +/- 6.6 and 22.3 +/- 14.6 micrograms/day) than the other insulin-treated patients (45.4 +/- 30.7 micrograms/day). In more than 90% of diet- and sulfonylurea-treated patients, UCPR exceeded 30 micrograms/day and UCPR/wt. exceeded 0.6 micrograms/day, kg. UCPR was less than 20 micrograms/day and UCPR/wt. less than 0.4 microgram/day,kg in more than 90% of IDDM patients, and less than 40 micrograms/day and 0.8 microgram/day,kg respectively in 80% of sulfonylurea-refractory patients. IDDM patients with more than 20 U/day of insulin doses had lower UCPR values. Longer duration of diabetes was associated with lower UCPR in IDDM patients. The results indicate that UCPR more than 30 micrograms/day or UCPR/wt. more than 0.6 micrograms/day,kg suggest non-insulin dependence, and UCPR less than 20 micrograms/day or UCPR/wt. less than 0.4 micrograms/day,kg suggest insulin dependence. Assay of UCPR provides a simple, non-invasive test for evaluating the degree of insulin dependence in diabetic patients. Topics: Adolescent; Adult; Aged; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Humans; Insulin; Middle Aged; Sulfonylurea Compounds | 1985 |
The C-peptide response to glucagon injections in IDDM and NIDDM patients.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fasting; Glucagon; Humans | 1985 |
Serum C-peptide content in nutritional diabetes.
Topics: Adolescent; Adult; Body Composition; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male | 1985 |
Effect of improved glycemic control by continuous subcutaneous insulin infusion on hormonal responses to insulin-induced hypoglycemia in type 1 diabetics.
Glucose counter-regulatory capacity and the hormonal responses to insulin-induced hypoglycemia were studied in eight type 1 diabetics before and after improvement of metabolic control by continuous subcutaneous insulin infusion (CSII). The intensified treatment resulted in a decrease in mean glycosylated hemoglobin from 11.6 +/- 0.5 to 9.3 +/- 0.4% within a mean period of 14 weeks. During a constant rate infusion of insulin (2.4 U/h), steady state levels of glucose appeared in all subjects. The steady state glucose level was identical before and after CSII. The counter-regulatory hormonal responses showed significantly higher epinephrine levels, while glucagon, growth hormone, and cortisol were not influenced. In parallel with the heightened epinephrine response the pulse rate response was significantly enhanced. The restitution of blood glucose after insulin hypoglycemia was not modified. It is concluded that a more vigorous catecholaminergic response to hypoglycemia is achieved after improved metabolic control by CSII. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Heart Rate; Hemoglobin A; Hormones; Humans; Hypoglycemia; Insulin Infusion Systems; Male; Middle Aged | 1985 |
Glycemic control and serum lipoproteins after total pancreatectomy.
Carbohydrate and lipid metabolism were studied in 10 patients who had undergone total pancreatectomy. The results were compared with Type I diabetic patients and normal subjects, all of whom were matched for age, sex and weight. At the same level of glycemic control, the daily need for insulin was significantly lower in the patients with pancreatogenic diabetes than in those with Type I diabetes. Concentrations of serum total VLDL and HDL triglyceride were higher in the pancreatectomized patients than in the diabetic or normal controls, whereas concentrations of serum total and LDL cholesterol were significantly lower. The composition of the VLDL, LDL and HDL particles was abnormal in the totally pancreatectomized patients as all three lipoprotein fractions were enriched in triglyceride. HDL2 cholesterol was similar in the totally pancreatectomized patients to that in the other two groups but HDL3 cholesterol was lower. Postheparin plasma lipoprotein lipase and hepatic lipase activities were normal. It is concluded that in totally pancreatectomized patients the changes in the lipoprotein profile on reflect more the action of various confounding factors, i.e. malabsorption, continuance of alcohol abuse and dietary changes than the impact of the diabetes itself. Topics: Adult; Blood Glucose; C-Peptide; Carbohydrates; Chronic Disease; Diabetes Mellitus, Type 1; Heparin; Humans; Lipids; Lipoprotein Lipase; Lipoproteins; Liver; Middle Aged; Pancreatectomy; Pancreatitis | 1985 |
Diabetes and impaired glucose tolerance. A prevalence estimate based on the Busselton 1981 survey.
We have estimated the prevalence of diabetes and impaired glucose tolerance from the Busselton 1981 Population Survey using the 1980 World Health Organization (WHO) criteria. Standardized to the Australian non-Aboriginal population aged 25 years and over, the prevalence rates in this white community were 2.5% for known diabetes; 0.9% for newly discovered diabetes; 2.9% for impaired glucose tolerance; and 6.3% for all categories of abnormal glucose tolerance. There appears to have been a real increase in the frequency of diabetes since 1966. Using fasting serum C-peptide values and clinical criteria, 14% of all diabetic subjects were insulin-dependent. The male:female ratio for all categories of abnormal glucose tolerance was 1.4:1. Data from the United States indicate spectacularly higher rates for diabetes and impaired glucose tolerance in the white population. A national study of the prevalence of diabetes and impaired glucose tolerance in Australia is recommended. For epidemiological purposes, a single blood glucose value two hours after a 75 g oral glucose tolerance test is sufficient to categorize glucose tolerance as defined by WHO. Topics: Adult; Age Factors; Aged; Australia; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Follow-Up Studies; Glucose Tolerance Test; Health Surveys; Humans; Male; Middle Aged; Prediabetic State; Sex Factors; Surveys and Questionnaires | 1985 |
Diabetes mellitus: customizing management.
Topics: Adult; Aging; Biguanides; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dietary Carbohydrates; Dietary Fats; Dietary Fiber; Female; Glucagon; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Male; Monitoring, Physiologic; Pregnancy; Pregnancy in Diabetics; Sulfonylurea Compounds | 1984 |
Tolbutamide does not alter insulin requirement in Type 1 (insulin-dependent) diabetes.
We examined whether tolbutamide has any acute or short-term effects on insulin action in Type 1 (insulin-dependent) diabetes. A euglycaemic glucose clamp was performed in seven Type 1 diabetic patients without clinical insulin resistance by infusing glucose at a constant rate of 0.01 mmol X kg-1 X min-1 for 3h together with a simultaneous insulin infusion using an 'artificial pancreas'. The insulin infusion rate required to maintain blood glucose at 6.7 mmol/l at a set low glucose infusion rate provides an index of insulin action in vivo. The euglycaemic clamp was performed on 3 separate days in the same patient: (1) in the basal state; (2) during simultaneous intravenous tolbutamide infusion of 0.5 g/h, and (3) after treatment with 2.5 g tolbutamide/day for 6 days in addition to insulin. The insulin infusion rate needed to maintain the set blood glucose level did not differ significantly between the three experimental conditions (1.2 +/- 0.2 versus 1.3 +/- 0.3 versus 1.2 +/- 0.3 U/h). Plasma glucagon, growth hormone, non-esterified fatty acid and glycerol levels did not differ between control or sulphonylurea treatment studies. The results suggest that tolbutamide does not exert any acute or short-term effects on insulin action in vivo in Type 1 diabetes. Our results do not provide support for the idea that this agent is a clinically useful adjunct to insulin in such patients. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Drug Synergism; Fatty Acids, Nonesterified; Glucagon; Glycerol; Humans; Insulin Infusion Systems; Male; Middle Aged; Somatostatin; Tolbutamide | 1984 |
[C-peptide in the insulin-dependent diabetic].
Plasma C-peptide levels were measured in classical insulin-dependent diabetics (group I) and in patients who had become insulin-dependent after a mean 12 years of non-insulin dependent diabetes (group II). All had been under insulin therapy for no more than 2 years. Metabolic control, as assessed by blood glucose and glycosylated A1C haemoglobin levels, was equally poor in both groups. The doses of insulin required were almost identical, though slightly higher in group II, while C-peptide levels were twice as high in group II patients as in group I patients. These findings suggest that patients with initially non-insulin dependent diabetes are more resistant to insulin than classical insulin-dependent diabetics. This low sensitivity to insulin might be due to age (which was more advanced in our group II patients) or might indicate that these patients still retain a degree of insulin-resistance that is characteristic of non-insulin dependent diabetes. Topics: Adult; Aged; Aging; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Resistance; Insulin Secretion; Male; Middle Aged | 1984 |
Adrenergic blockade alters glucose kinetics during exercise in insulin-dependent diabetics.
We investigated the effects of alpha and/or beta adrenergic blockade (with phentolamine and/or propranolol) on glucose homeostasis during exercise in six normal subjects and in seven Type I diabetic subjects. The diabetics received a low dose insulin infusion (0.07 mU/kg X min) designed to maintain plasma glucose at approximately 150 mg/dl. In normals, neither alpha, beta, nor combined alpha and beta adrenergic blockade altered glucose production, glucose uptake, or plasma glucose concentration during exercise. In diabetics, exercise alone produced a decline in glucose concentration from 144 to 116 mg/dl. This was due to a slightly diminished rise in hepatic glucose production in association with a normal increase in glucose uptake. When exercise was performed during beta adrenergic blockade, the decline in plasma glucose was accentuated. An exogenous glucose infusion (2.58 mg/kg X min) was required to prevent glucose levels from falling below 90 mg/dl. The effect of beta blockade was accounted for by a blunted rise in hepatic glucose production and an augmented rise in glucose utilization. These alterations were unrelated to changes in plasma insulin and glucagon levels, which were similar in the presence and absence of propranolol. In contrast, when the diabetics exercised during alpha adrenergic blockade, plasma glucose concentration rose from 150 to 164 mg/dl. This was due to a significant increase in hepatic glucose production and a small decline in exercise-induced glucose utilization. These alterations also could not be explained by differences in insulin and glucagon levels. We conclude that the glucose homeostatic response to exercise in insulin-dependent diabetics, in contrast to healthy controls, is critically dependent on the adrenergic nervous system. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Epinephrine; Female; Glucagon; Humans; Insulin; Kinetics; Male; Norepinephrine; Phentolamine; Physical Exertion; Propranolol; Receptors, Adrenergic, alpha; Receptors, Adrenergic, beta; Tritium | 1984 |
Relation of immunoreactive gastric inhibitory polypeptide to changes in glycaemic control and B cell function in type 1 (insulin-dependent) diabetes mellitus.
The effect of strict glycaemic control on plasma immunoreactive gastric inhibitory polypeptide (IR-GIP) concentrations and pancreatic B cell function as estimated by plasma C-peptide was evaluated in 14 Type 1 (insulin-dependent) diabetics. The effect was estimated by giving a test meal before (test 1) and after (test 2) 1 week with near normal blood glucose control (mean blood glucose 6.7 +/- 0.2 mmol/l) and again 3 weeks later (test 3) in the outpatient clinic. The glycaemic control was significantly improved at test 2 and test 3 compared with that of test 1. The IR-GIP concentrations before and after the meals were similar at all three tests and not different from those found in 21 normal controls. In 8 patients with a significant B cell response at test 1, B cell function was significantly improved both at test 2 and test 3 but no change in fasting or post-prandial IR-GIP concentrations was found and no correlation between B cell function and IR-GIP existed. We conclude that strict glycaemic control improves B cell function but does not modulate plasma IR-GIP concentrations. Factors other than GIP seem to be of greater importance in determining the magnitude of B cell function in Type 1 diabetes. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Food; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1984 |
A prospective analysis of islet-cell cytotoxic antibodies in insulin-dependent diabetic children. Transient effects of plasmapheresis.
We determined the effects of plasmapheresis on cytotoxic antibodies to islet cells in 10 children (aged 11-16 yr) with newly diagnosed insulin-dependent diabetes mellitus (IDDM), as well as the plasma levels of antibodies over the next 30 mo and their relation to serum C-peptide concentrations. Complement-dependent, antibody-mediated cytotoxicity (C'AMC) in plasma was measured in a 51Cr release assay using monolayers of the rat islet cell line RINm5F. Cytotoxic antibodies decreased in most IDDM subjects treated by plasmapheresis four times within 2 wk of diagnosis; however, the decreases were small and lasted less than 2-3 days. Thus, both before and after plasmapheresis, 7 of the 10 IDDM children were C'AMC-positive (51Cr release greater than 2 SD above mean for 13 healthy children). After 18-30 mo, only 2 of the original 7 IDDM children with C'AMC-positive plasmas were still positive, and 1 of the original 3 IDDM children without significant cytotoxicity had become positive. Meal-stimulated serum C-peptide responses, measured from diagnosis to 18-30 mo later, did not correlate with C'AMC values. We conclude that (1) plasmapheresis has only transient effects on islet-cytotoxic antibody levels in children with IDDM; (2) these antibodies decrease in most, but not all, subjects over the first 18 mo after diagnosis; and (3) the level of cytotoxic antibodies in IDDM plasma at diagnosis has no predictive effect on residual B-cell function. Topics: Adolescent; Antibodies; Antibody-Dependent Cell Cytotoxicity; C-Peptide; Cells, Cultured; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Plasmapheresis; Prospective Studies; Time Factors | 1984 |
Effects of cyclosporine immunosuppression in insulin-dependent diabetes mellitus of recent onset.
Type I diabetes may be an autoimmune disorder, although the evidence is largely circumstantial. The natural history of the disease after diagnosis includes partial remission in most patients, but only about 3 percent achieve transient insulin independence. beta Cell function, as indicated by the plasma concentration of C-peptide, is lost over 6 to 30 months and islet cell antibodies disappeared over 1 to 2 years. This article describes a pilot study in which 41 patients were treated with the immunosuppressive agent cyclosporine for 2 to 12 months. Of 30 patients treated within 6 weeks of diagnosis, 16 became insulin independent with concentrations of plasma C-peptide in the normal range and decreasing titers of islet cell antibodies. Of 11 patients who entered the study 8 to 44 weeks after diagnosis, two achieved this state. These results indicate that a controlled trial of the effects of cyclosporine in type I diabetes should be conducted. Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Creatinine; Cyclosporins; Diabetes Mellitus, Type 1; Female; Gingival Hyperplasia; Humans; Hypertrichosis; Insulin; Islets of Langerhans; Kidney; Male; Middle Aged | 1984 |
Mechanisms of glucagon secretion during insulin-induced hypoglycemia in man. Role of the beta cell and arterial hyperinsulinemia.
To elucidate the mechanisms controlling the response of glucagon to hypoglycemia, a vital component of the counterregulatory hormonal response, the role of intraislet insulin was studied in seven normal subjects and five subjects with insulin-dependent diabetes mellitus (IDDM) (of less than 15-mo duration). In the normal subjects, hypoglycemia (arterial plasma glucose [PG] 53 +/- 3 mg/dl) induced by an intravenous insulin infusion (30 mU/m2 X min for 1 h, free immunoreactive insulin [FIRI] 58 +/- 2 microU/ml) elicited a 100% fall in insulin secretion and an integrated rise in glucagon of 7.5 ng/ml per 120 min. When endogenous insulin secretion was suppressed by congruent to 50 or congruent to 85% by a hyperinsulinemic-euglycemic clamp (FIRI 63 +/- 1.5 or 147 +/- 0.3 microU/ml, respectively) before hypoglycemia, the alpha cell responses to hypoglycemia were identical to those of the control study. When the endogenous insulin secretion was stimulated by congruent to 100% (hyperinsulinemic-hyperglycemic clamp, FIRI 145 +/- 1.5 microU/ml, PG 132 +/- 2 mg/dl) before hypoglycemia, the alpha cell responses to the hypoglycemia were also superimposable on those of the control study. Finally, in C-peptide negative diabetic subjects made euglycemic by a continuous overnight intravenous insulin infusion, the alpha cell responses to hypoglycemia were comparable to those of normal subjects despite absent beta cell secretion, and were not affected by antecedent hyperinsulinemia (hyperinsulinemic-euglycemic clamp for 2 h, FIRI 61 +/- 2 microU/ml). These results indicate that the glucagon response to insulin-induced hypoglycemia is independent of the level of both endogenous intraislet and exogenous arterial insulin concentration in normal man, and that this response may be normal in the absence of endogenous insulin secretion, in contrast to earlier reports. Thus, loss of beta cell function is not responsible for alpha cell failure during insulin-induced hypoglycemia in IDDM. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Humans; Hyperinsulinism; Hypoglycemia; Insulin; Islets of Langerhans | 1984 |
Insulin antibodies in diabetic children treated with monocomponent porcine insulin from the onset: relationship to B-cell function and partial remission.
Insulin antibodies expressed as insulin binding capacity of IgG were determined in 50 Type 1 (insulin-dependent) diabetic children who have been treated with monocomponent porcine insulin from the onset of the disease. During the follow-up period of 0.5-5.5 years (mean +/- SD: 3.2 +/- 1.6 years), 26 out of 50 patients (52%) developed detectable insulin antibodies. These patients had significantly lower maximal C-peptide responses to a standardized breakfast 9 months after onset of diabetes (mean 0.24 pmol/ml, p less than 0.001) than those without insulin antibodies (mean 0.47 pmol/ml). In addition, patients with antibodies showed both significantly higher insulin requirements at 9 months (p less than 0.05), and shorter remissions (p less than 0.01) than those without. It is concluded that even 'small' amounts of insulin antibodies may be biologically significant and have negative effects on B-cell function and metabolic balance. Topics: Adolescent; B-Lymphocytes; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Histocompatibility Antigens Class II; HLA-DR4 Antigen; Humans; Immunoglobulin G; Insulin; Insulin Antibodies; Insulin, Regular, Pork; Male | 1984 |
A study of serum free C-peptide responses to oral glucose load in diabetic patients: with special reference to types of diabetes and methods of treatment.
Serum free C-peptide immunoreactivities (serum free CPR) during a 100 g oral glucose tolerance test (OGTT) were measured in 21 patients with insulin-dependent diabetes mellitus (IDDM, with abrupt onset and ketosis-prone), 57 insulin-treated patients with noninsulin-dependent diabetes mellitus ( INIDDM , with gradual onset and not ketosis-prone), 39 oral hypoglycemic agent-treated patients with noninsulin-dependent diabetes mellitus ( ONIDDM ) and 9 healthy young men for control study. Although the fasting blood glucose value of the INIDDM group was not significantly different from that of the IDDM and ONIDDM groups, the free CPR response at each interval during OGTT in the INIDDM group was significantly higher than that in the IDDM group and lower than that in the ONIDDM group. The sum of serum free CPR during OGTT (sigma serum free CPR) was found to be negatively correlated to the duration of insulin treatment either in bivariate or multivariate analysis in INIDDM patients. Using 9.5 ng/ml as an index, all sigma serum free CPR values in the ONIDDM group were above this index, whereas all the values except one in the IDDM group were below it. The values in the INIDDM were scattered within the ranges of the other two groups. The insulinogenic index delta serum free CPR/delta blood glucose (30 min-fasting) of the ONIDDM group was significantly lower than that of normal subjects, although sigma serum free CPR values were not significantly different. The results indicate that: 1. Residual pancreatic B-cell function in INIDDM patients is lower than that in ONIDDM patients and is negatively correlated to the duration of insulin treatment in INIDDM patients. 2. Measuring serum free CPR may be a discriminative method for establishing insulin dependency in insulin-treated patients. 3. Impairment of early insulin secretion after the oral glucose load is a distinguished characteristic of diabetic patients. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Humans; Hypoglycemic Agents; Insulin; Male; Middle Aged | 1984 |
Improvement of metabolic control in diabetic patients during mebendazole administration: preliminary studies.
After the observation of decreasing insulin resistance in a diabetic patient during treatment with mebendazole for nematosis, we investigated the effect of mebendazole on metabolic control in six Type 1 (insulin-dependent) and six Type 2 (non-insulin-dependent) diabetic patients, eight of whom were chronically resistant to conventional treatment. Before and after mebendazole treatment for 1 month, plasma glucose and serum C-peptide concentrations were determined both fasting and 4 h after a mixed breakfast. Improvements in fasting blood glucose concentrations occurred in Type 1 (12.83 +/- 1.11 versus 6.56 +/- 0.56 mmol/l; p less than 0.05) and Type 2 (10.22 +/- 0.56 versus 7.56 +/- 0.67 mmol/l; p less than 0.05) diabetic patients and were associated with increases in post-cibal C-peptide responses in Type 1 and Type 2 diabetic patients. Following discontinuation of mebendazole, metabolic control deteriorated in five out of the six Type 1 diabetic patients and in all the Type 2 diabetic patients. We conclude that mebendazole increases insulin secretion, and decreases plasma glucose concentration in Type 1 and Type 2 diabetic patients. However, these beneficial effects may be transient. Topics: Adult; Benzimidazoles; Blood Glucose; C-Peptide; Chlorpropamide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids, Nonesterified; Humans; Insulin; Insulin Resistance; Mebendazole | 1984 |
[The pancreatic reserve in diabetes mellitus by the determination of serum C-peptide using radioimmunoassay].
Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Male; Pancreas; Radioimmunoassay | 1984 |
Lack of negative feed-back regulation of insulin on the responses of gastric inhibitory polypeptide, insulin, glucagon and pancreatic polypeptide to a meal in insulin treated diabetics.
The effect of insulin on the secretion of immunoreactive gastric inhibitory polypeptide, insulin (as measured by C-peptide), glucagon and pancreatic polypeptide during and after a test meal was examined in seven diabetic patients treated with high insulin doses (mean 1.12 +/- 0.12 IU/kg X 24 h) before and after a reduction of the insulin dose (to 0.62 +/- 0.04 IU/kg X 24 h, p less than 0.02). While plasma insulin concentrations were significantly higher on the higher dose, no significant differences were found in the responses of immunoreactive gastric inhibitory polypeptide, C-peptide, glucagon and pancreatic polypeptide to the two meals. Blood glucose concentrations were not significantly different at the two tests. It thus seems that insulin has no direct effect on the secretion of these substances after a meal in insulin-treated diabetics. Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Female; Food; Gastric Inhibitory Polypeptide; Gastrointestinal Hormones; Glucagon; Homeostasis; Humans; Insulin; Male; Middle Aged; Pancreatic Polypeptide | 1984 |
Remissions in newly diagnosed type 1 (insulin-dependent) diabetes: influence of interferon as an adjunct to insulin therapy.
We studied the effect of interferon as an adjunct to conventional insulin therapy on the early course of Type 1 diabetes in 43 newly diagnosed patients. Compared with conventional therapy, interferon administration slightly delayed the improvement of glucose homeostasis and the rise of high density lipoprotein cholesterol, while C-peptide secretion was unaffected. Independent of the type of therapy, 18 patients (42%) entered partial remission. The remission began 2.0 +/- 0.6 months (mean +/- SEM) from the start of therapy and lasted for 4.1 +/- 1.1 months. Seven patients (16%) were still in remission 1 year after diagnosis. The patients who entered remission had higher initial C-peptide secretion, lower glycosylated haemoglobin levels and better initial control than patients without remission. Thus, interferon provided no benefits as an adjunct to conventional insulin therapy in unselected patients with newly diagnosed Type 1 diabetes. An important factor for the development of remission was the presence of C-peptide secretion at the time of diagnosis. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Cholesterol, HDL; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Insulin; Interferon Type I; Male; Virus Diseases | 1984 |
Demonstration of a dawn phenomenon in normal human volunteers.
To ascertain whether the dawn phenomenon occurs in nondiabetic individuals and, if so, whether it is due to an increase in glucose production or a decrease in glucose utilization, we determined plasma concentrations of glucose, insulin, C-peptide, and counterregulatory hormones, as well as rates of glucose production, glucose utilization, and insulin secretion at one-half-hourly intervals between 1:00 and 9:00 a.m. in eight normal volunteers. After 5:30 a.m., plasma glucose, insulin, and C-peptide concentrations all increased significantly; rates of glucose production, glucose utilization, and insulin secretion also increased (all P less than 0.05). Plasma cortisol, epinephrine, and norepinephrine increased significantly from nocturnal nadirs between 4:00 and 6:30 a.m. Plasma growth hormone, which had increased episodically between 1:00 and 4:30 a.m., decreased thereafter nearly 50% (P less than 0.05). Plasma glucagon did not change significantly throughout the period of observation. These results indicate that a dawn-like phenomenon, initiated by an increase in glucose production, occurs in nondiabetic individuals. Thus, early morning increases in plasma glucose concentrations and insulin requirements observed in IDDM and NIDDM may be an exaggeration of a physiologic circadian variation in hepatic insulin sensitivity induced by antecedent changes in catecholamine and/or growth hormone secretion. Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Epinephrine; Growth Hormone; Homeostasis; Humans; Hydrocortisone; Insulin; Male; Norepinephrine | 1984 |
[The importance of the radioimmunologic study of the impairment of insulin secretion as an atherogenic factor].
Using a radioimmunoassay a low C-peptide fasting level was revealed in children, pregnant and lying-in women as well as in patients with insulin-dependent diabetes mellitus. After breakfast and insulin administration with curative purposes the IRI concentration in children increased whereas the C-peptide level changed insignificantly. Changes of the insulin secretion were more noticeable in severe diabetes mellitus with vascular complications and in disease decompensation. The atherogenic nature of the lipid metabolism (an increase in the cholesterol, triglyceride and beta-lipoprotein levels), changes in the liver and a tendency to vascular involvement are the results of insulin effect inadequacy. Such metabolic derangements in pregnant women create unfavorable conditions for the development of fetus and may lead to early atherogenic processes. Topics: Adult; Arteriosclerosis; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Fetal Blood; Humans; Insulin; Insulin Secretion; Lipids; Pregnancy; Pregnancy in Diabetics; Radioimmunoassay | 1984 |
[Assay of C-peptide in diabetes in children and adolescents].
Thirty eight children and adolescents aged 3 to 19 years with insulin-dependent diabetes had basal plasma C-peptide levels 50 to 70 p. 100 lower than comparable non-diabetic subjects. An appreciable residual fasting endogenic secretion greater than 1 ng/ml was found in half the patients during the first two years after the onset of diabetes. After this period, the concentrations were almost always lower than 1 ng/ml and in half the cases, at the lower limit of detection. In addition, it was difficult to stimulate C-peptide secretion by food or drugs. The effects of variations in blood glucose were made allowance for by using molar C-peptide/glucose ratio. This gives a better evaluation of the inverse relationship between residual pancreatic function and the duration of the diabetes and of the degree of residual beta-langerhans secretion to help obtain stable metabolic equilibrium. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Time Factors | 1984 |
[Long-term course of type I-simulating type II-diabetes mellitus].
In only few cases of primarily non- insulin-dependent diabetes mellitus after many years an absolute insulin dependency can develop. Within 5000 patients of a diabetic outpatient clinic in 2 years this happened in 21 patients. These patients offered a C-peptide-secretion after stimulation which was typical for an insulin dependent diabetes. The investigation of HLA-frequencies showed a marked increase of the DR 3 und DR 4 loci. These results demonstrate that obviously the genetically as type I characterized diabetes may appear clinically in the picture of type II-diabetes for many years. This must be taken in consideration in therapeutic or epidemiologic questions. Topics: Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diagnosis, Differential; Female; Follow-Up Studies; HLA Antigens; Humans; Insulin; Male | 1984 |
Evidence of delayed beta-cell destruction in type 1 (insulin-dependent) diabetic patients with persisting complement-fixing cytoplasmic islet cell antibodies.
Forty-four children with Type 1 (insulin-dependent) diabetes (aged 0.7-16.7 years) were observed from diagnosis for cytoplasmic islet cell antibodies and serum C-peptide concentrations. Islet cell antibodies were analysed by indirect immunofluorescence for both conventional IgG and complement-fixing antibodies. Thirty-seven children (84%) were found to be positive for conventional islet cell antibodies at diagnosis, and 21 (48%) remained positive over the observation period. Twenty-six patients (59%) were positive for complement-fixing antibodies at diagnosis and eight remained so during the follow-up period. The serum C-peptide concentrations increased significantly during the first 3 months after diagnosis, after which there was a gradual decrease in the levels. Those children who remained positive for complement-fixing antibodies over the observation period had significantly higher serum C-peptide concentrations on several occasions during the second year and had also a higher integrated serum C-peptide concentration over the initial 2 years than those who became negative for complement-fixing antibodies. These observations suggest that the continuous production of complement-fixing islet cell antibodies in those patients who are positive for these antibodies at diagnosis presupposes the preservation of a sufficient amount of functioning beta cells for antigenic stimulation. These results support the view that the complement-fixing islet cell antibodies reflect ongoing destructive processes in the beta cells. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Complement Fixation Tests; Diabetes Mellitus, Type 1; Female; Follow-Up Studies; Humans; Immunoglobulin A; Infant; Insulin Antibodies; Islets of Langerhans; Male | 1984 |
Beta-cell function recovery is not the only factor responsible for remission in type I diabetics: evaluation of C-peptide secretion in diabetic children after first metabolic recompensation and at partial remission phase.
In 9 newly diagnosed type I diabetic children the residual beta-cell secretory capacity was examined after stimulation with oral glucose load, glucagon and iv glucose plus arginine hydrochloride administration shortly after diagnosis and in the partial remission phase. A significant C-peptide secretion induced by these substances except by iv glucose was found at both investigation times. Whereas beta-cell function did only slightly increase from the initial testing to the measurements in the partial remission, beta-cell sensitivity increased significantly (p less than 0.05). The data suggest that "partial remission" referred to C-peptide secretion starts very early after insulin treatment and that other factors, possibly a decrease of peripheral insulin resistance, are involved in the improved metabolic control in partial remission phase. Topics: Adolescent; Arginine; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Male; Time Factors | 1984 |
[Clinical characteristics and hormonal-metabolic homeostasis in patients with insulin-dependent diabetes mellitus with stable and labile courses].
Combined examination of 117 patients with insulin-dependent diabetes mellitus revealed the clinical and hormonal features of stable and labile diseases. Emphasis is laid on the complexity of the lability phenomenon; evidence is given for the necessity of differentiating between genuine lability and that of the iatrogenic type. The importance of hormonal shifts (depletion of the secretory capability of the insulin-producing apparatus and reduction of contrainsular effects) for the origin of destabilization of glucose homeostasis is discussed. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Glucose Tolerance Test; Homeostasis; Humans; Insulin; Insulin Antibodies; Male; Middle Aged; Thyroid Hormones; Time Factors | 1984 |
Amniotic fluid content of glucose, C-peptide and insulin in normal and diabetic pregnancies.
Glucose, C-peptide and insulin concentrations in amniotic fluid were measured in 63 women, 19 of whom had insulin-dependent diabetes. The amniotic fluid glucose concentration was higher in the diabetic (37.4 +/- 4.1) than in the normal women (19.4 +/- 5.1 mg/dl; P less than 0.01). The amniotic fluid insulin concentration was higher in diabetic than non diabetic women (15.9 +/- 3.1 versus 8.9 +/- 2.1 microU/ml; P less than 0.01). The C-peptide concentration was also higher in the amniotic fluid of diabetic women than normal (1.60 +/- 0.66 vs 0.26 +/- 0.15 nmol/l; P less than 0.001). The lecithin/sphingomyelin (L/S) ratio in the amniotic fluid was greater than 2 in 61 mothers; only two diabetic patients had an L/S ratio lower than 2. Five neonates of diabetic mothers were macrosomic and three of these were also hypoglycaemic. A negative correlation was observed in diabetic women between insulin and C-peptide concentrations in the amniotic fluid and Apgar score of the newborn infants both at 1 and 5 minutes; no correlation was found on the contrary with the amniotic glucose. In the prognostic evaluation of the fetus with a diabetic mother one must consider many parameters. Among these more consideration must be given to the levels of C-peptide and insulin in amniotic fluid than to glucose level. Topics: Amniotic Fluid; Apgar Score; C-Peptide; Diabetes Mellitus, Type 1; Female; Gestational Age; Glucose; Humans; Infant, Newborn; Insulin; Pregnancy; Pregnancy in Diabetics | 1984 |
Glycosylated haemoglobin and serum insulin antibodies in type I diabetes.
Type 1 diabetics receiving once (Group 1, n = 72) and twice (Group 2, n = 48) daily subcutaneous injections of conventional beef insulin were compared, on a cross-sectional basis, in respect of insulin antibody binding by serum and total glycosylated haemoglobin (HbA1). Patients in Group 1 had higher insulin antibody binding (25.2 +/- 15.8% vs 17.0 +/- 13.9%; p less than 0.01) and higher HbA1 levels (12.5 +/- 2.0% vs 11.0 +/- 1.8%; p less than 0.001) than patients in Group 2. An inverse correlation (tau = -0.28, p less than 0.01) was observed between HbA1 and insulin antibody binding in C-peptide non-secretors of Group 1 but not in Group 1 C-peptide secretors, nor in C-peptide secretors and/or non-secretors of Group 2. It is suggested that in Type 1 diabetics who receive a single daily insulin injection and who have no endogenous insulin secretion, insulin antibodies may aid glycaemic control by prolonging insulin action. Topics: Adult; Animals; Antibodies; Blood Glucose; C-Peptide; Cattle; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Humans; Insulin; Male | 1984 |
[Islet beta-cell function in failures following sulfonylurea therapy in diabetics, by determination of serum C-peptide].
Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glucagon; Humans; Islets of Langerhans; Male; Middle Aged; Sulfonylurea Compounds | 1984 |
[Osmotic homeostatic characteristics of pregnant women with diabetes mellitus and of their fetuses].
Topics: Aldosterone; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Homeostasis; Humans; Insulin Antibodies; Osmolar Concentration; Pregnancy; Pregnancy in Diabetics; Water-Electrolyte Balance | 1984 |
[Plasma glucose and C-peptide after ingestion of sucrose and starch in controlled insulin-dependent diabetics. Importance of glucose availability].
Oral tests using 50 g of sucrose and 100 g of white bread were carried out in ten insulin-dependent diabetics (four with signs of residual B-cell function and in six without). Plasma glucose and C-peptide (CPR) were estimated during the 180 minutes after ingestion. After bread intake, plasma glucose increase was significantly delayed (30 min.). Hyperglycemia (greater than 2.5 g/l) lasted significantly longer after bread then after sucrose ingestion. Blood glucose decreased more quickly in subjects with residual B-cell function than in subjects without. CPR was not significantly modified by either of the carbohydrate loads. In the controlled insulin-dependent diabetic the hyperglycemia observed results from the ease of carbohydrates hydrolysis and from the amount of available glucose. The role of fructose seems weak in the case of sucrose because its conversion to glucose would be minimized in the presence of metabolic normalization as indicated by a well controlled blood glucose. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Humans; Male; Middle Aged; Nutritive Value; Starch; Sucrose; Time Factors | 1984 |
[C-peptide].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Hypoglycemia | 1984 |
C-peptide response to a glucose load in young blacks and Indians with insulin-dependent diabetes mellitus.
Residual beta cell function based on C-peptide assays was estimated in 39 patients (27 Blacks, 12 Indians) with insulin-dependent diabetes mellitus and 18 controls (9 Blacks, 9 Indians) using glucose as a stimulus. The diabetic patients showed significantly lower maximal C-peptide values (mean 0,53 +/- 0,08 nmol/l) and delayed peak levels (mean 137 minutes after ingestion of glucose) compared with the controls (mean 2,15 +/- 0,31 nmol/l and 54 minutes respectively). Just over 20% of the patients had no residual beta cell function, this conclusion being made on the basis of undetectable basal C-peptide levels which failed to rise after glucose stimulation. A significant correlation was seen between glycosylated haemoglobin levels and maximal C-peptide levels (r = 0,45, P less than 0,01). C-peptide levels tended to be lower in Black than in Indian patients, but the difference was not significant. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucose; Glucose Tolerance Test; Glycated Hemoglobin; Humans; Male; Time Factors | 1984 |
Exocrine pancreatic function in diabetes mellitus.
An investigation of serum immunoreactive trypsin concentration and pancreatic isoamylase activity in patients with diabetes mellitus has shown that exocrine pancreatic deficit is maximal in insulin dependent diabetics, intermediate in those controlled with sulphonylureas, and absent in patients controlled with biguanides or diet or both. A significant correlation between the serum concentrations of both these pancreatic enzymes and C peptide was found. Serum pancreatic enzyme concentrations were not related to glycosylated haemoglobin concentrations, the dosage of insulin, or the age of onset of diabetes. The concentration of immunoreactive trypsin was found to be low in most of the insulin dependent diabetics in whom this enzyme was measured at the time of the clinical onset of diabetes. Thus exocrine pancreatic deficit in diabetes closely parallels the endocrine beta cell deficit and occurs concurrently with, or antedates, the clinical presentation of type I diabetes. It is therefore possible that in type I diabetes similar mechanisms are entailed in the pathogenesis of impaired endocrine and exocrine pancreatic function. Topics: Biguanides; C-Peptide; Diabetes Mellitus, Type 1; Diet, Diabetic; Hemoglobin A; Humans; Isoamylase; Pancreas; Sulfonylurea Compounds; Trypsin | 1984 |
Metabolic control in children and adolescents with insulin-dependent diabetes mellitus.
The metabolic control, assessed from the mean daily glucosuria, mean daily glucosuria index based on home tests, and mean haemoglobin A1 (HbA1) concentrations during 1980, and the influence of various factors on the control were analysed in 177 diabetic children and adolescents. The mean daily glucosuria was 21% of the carbohydrates in the subscribed diet, and the mean glucosuria index 55%. The mean HbA1 was 14.0%. Boys had better metabolic control than girls. Good motivation towards treatment was associated with better metabolic control. There was a negative correlation between metabolic control and both the age of the child and the duration of diabetes. Prepubertal children were better controlled than those in puberty. Adherence to the dietary regimen was related to better control, as was the patient's endogenous insulin secretion, measured by serum C-peptide concentration. There was also an association between the season and the metabolic control, the control being better in the spring than during the other seasons. On the basis of these results male sex, a good motivation towards treatment, residual beta-cell function and adherence to the prescribed diet favor good metabolic control, while a long duration of the disease, the presence of puberty and relatively high age in childhood are factors impairing the metabolic control. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycated Hemoglobin; Glycosuria; Humans; Male; Patient Compliance; Seasons | 1984 |
[Insulin reserve of insulin-dependent diabetics. Role of C-peptide in the hormonal balance in diabetes].
Insulin secretion was investigated in 65 insulin-dependent diabetic patients by determining C peptide levels before and after stimulation with either an 800 calories test meal or an injection of glucagon or arginine i.v. Most patients had very low basal C peptide levels and response to all stimulation tests was poor as compared to controls. In normal subjects, response to glucagon or arginine stimulation appeared to be slightly stronger than response to test meal stimulation. There was apparently no correlation between diabetes control, as assessed by haemoglobin A1c values, and C peptide levels before and after stimulation. On the other hand, C peptide levels were inversely proportional to the duration of diabetes. Finally, C peptide levels after test meal stimulation were found to correlate with the doses of insulin administered. Topics: Adult; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Female; Homeostasis; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Peptides; Time Factors | 1983 |
Diabetic keratopathy as a manifestation of peripheral neuropathy.
In a study of 102 patients (64 women and 38 men; 63 whites and 39 nonwhites; 77 with adult-onset disease and 25 with juvenile-onset disease), the data, after being adjusted for age, showed that diabetic peripheral neuropathy was associated with diabetic keratopathy. The strongest predictor of both keratopathy and corneal fluorescein staining was vibration perception threshold in the toes (P less than .01); the severity of keratopathy was directly related to the degree of diminution of peripheral sensation. Other predictors of keratopathy were reduced tear break-up time (P less than .03), the type of diabetes (P less than .01), and metabolic status, shown by fasting C-peptide levels (P less than .01). No significant relationships were found between keratopathy and tear glucose levels, endothelial cell densities, corneal thickness, or duration of disease. Topics: Aged; C-Peptide; Corneal Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Neuropathies; Female; Humans; Male; Middle Aged; Peripheral Nervous System Diseases; Triglycerides; Vibration | 1983 |
Effect of poor diabetic control and obesity on whole body protein metabolism in man.
We have investigated whole body protein turnover in the fasted state in five normal men, five male Type 1 diabetic patients off insulin therapy, and five obese women, using IV 13C-leucine as a tracer. In diabetic patients, there was, as expected, a greater net loss of protein in the fasted state than in normal subjects. However, contrary to animal and studies in vitro, our diabetic patients in the fasted state showed a greater rate of protein synthesis than normal subjects (p less than 0.01). The increased net loss of protein in diabetic patients compared with normal subjects arose because, in the diabetic patients, protein breakdown was increased even more than protein synthesis under the conditions of this study. Plasma leucine concentration was higher in diabetic and in insulin-insensitive obese patients than in normal subjects (p less than 0.01), and higher in diabetic than in obese patients (p less than 0.05). The rate of protein synthesis per kg lean body mass was also higher in diabetic patients than in obese or normal subjects (p less than 0.01), and higher in obese than normal subjects (p less than 0.05). We conclude that, in human subjects, whole body leucine and protein metabolism are very sensitive to the action of insulin. Topics: Adult; Bicarbonates; Blood Glucose; C-Peptide; Carbon Isotopes; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Leucine; Male; Obesity; Proteins; Reference Values; Sodium Bicarbonate | 1983 |
Residual B cell function in diabetic children as determined by urinary C-peptide.
C-peptide was determined in 24-h urine collections and in fasting plasma of 27 Type 1 (insulin-dependent) diabetic children (duration of disease 0-6 years) and in 11 matched normal children. Grouping the patients according to duration of disease from onset to 6 years, it was found that in the first year of disease the B cell reserve was a mean of 4.89 +/- 1.95 pmol X mg creatinine-1. 24 h-1 compared with a mean of 24.51 +/- 2.91 pmol X mg-1 X 24 h-1 in the control group. A further diminution was seen with increase in the duration of disease, until after 6 years when only traces of C-peptide could be detected. There was a good correlation between the levels of plasma C-peptide and urinary C-peptide values as related to creatinine (r = 0.89; p = less than 0.001). In view of this, and since it is simpler and less traumatic to obtain frequent urine samples from children than it is to obtain blood samples, it was felt that the determination of urinary C-peptide constitutes a valuable tool in the evaluation of the diabetic child. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans; Peptides | 1983 |
B-cell function and islet cell and other organ-specific autoantibodies in relatives to insulin-dependent diabetic patients.
The pancreatic B-cell function (glucose tolerance, C-peptide release) and organ-specific autoantibodies, including islet cell cytoplasmic and cell surface (mouse), were studied in 45 first-degree relatives of patients with insulin-dependent diabetes mellitus diagnosed before the age of 30 years. Compared to 107 healthy persons without any family history of either insulin-dependent or non-insulin-dependent diabetes mellitus, the prevalence of autoantibodies was increased among the relatives. The prevalence of islet cell antibodies did not differ between relatives and controls and none of the individuals had complement-fixing islet cell antibodies. There was no difference in glucose tolerance or C-peptide release between relatives and controls, whether they had autoantibodies or not. At a three-year follow-up, none of the individuals had developed insulin-dependent diabetes. Topics: Adult; Autoantibodies; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Male | 1983 |
Observations on B-cell function after segmental pancreatic allotransplantation in diabetic patients.
Topics: Adrenal Cortex Hormones; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Hyperglycemia; Insulin; Insulin Antibodies; Islets of Langerhans; Male; Middle Aged; Pancreas Transplantation; Phenytoin | 1983 |
[Evaluation of residual functional beta-cell response in childhood and juvenile diabetes in relation to early diagnosis and to the forms of onset of the disease].
Topics: Adolescent; Arginine; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male | 1983 |
[Diabetes-specific hand changes in type I diabetes mellitus].
Diabetes-specific hand alterations (cheirarthropathy) were observed in 44 out of a total of 215 children and adolescents with insulin-dependent diabetes. In 28 of them limitations of movement in the proximal or (and) distal interphalangeal joints of one finger, and in the remaining 16 patients changes of at least two fingers were seen. Hand and shoulder joints or the vertebral column were not affected. In a control group of 110 probands without metabolic disorder only five showed cheirarthropathy. The frequency of diabetes-specific alterations of the hand increased with the age of the patients, the duration of diabetes and insulin requirements. In particular, the quality of metabolic control is of paramount importance for the as yet unclear pathogenesis of cheirarthropathy. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Contracture; Diabetes Mellitus, Type 1; Hand Deformities, Acquired; Humans; Infant; Insulin | 1983 |
An association between complement-fixing cytoplasmic islet cell antibodies and endogenous insulin secretion in children with insulin-dependent diabetes mellitus.
Cytoplasmic islet cell antibodies and endogenous insulin secretion were studied in 184 children and adolescents having insulin-dependent diabetes mellitus (IDDM) in a cross-sectional study. The mean age of the subjects was 12.3 yr (range: 2.8-19.2 yr), and the mean duration of diabetes was 4.6 yr (range: 0.1-15.6 yr). Islet cell antibodies (ICA) were determined by both the indirect immunofluorescence (IF-ICA) and the complement-fixing (CF-ICA) methods. Forty-four patients (23.9%) were positive with respect to both IF- and CF-ICA, 54 patients (29.3%) had only IF-ICA, and 86 patients had no ICA. The patients having CF-ICA had a significantly higher endogenous insulin secretion in comparison with the patients who were only IF-ICA positive. The difference between the groups remained significant even when the age at onset of diabetes and the duration of the disease were taken into account. This finding, revealing an association between CF-ICA and endogenous insulin secretion, suggests that complement-fixing antibodies are seen only if the beta-cell mass is sufficiently preserved. The result contradicts the hypothesis, based on studies in vitro, that CF-ICA should be involved in the selective beta-cell damage in IDDM. Topics: Adolescent; Adult; Aging; Antibodies; Autoantibodies; C-Peptide; Child; Child, Preschool; Complement Fixation Tests; Diabetes Mellitus, Type 1; Fluorescent Antibody Technique; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male | 1983 |
Beta-cell function assessed by plasma C-peptide evaluation in diabetic thalassaemic patients.
In order to investigate the pancreatic function in patients with thalassaemia major, plasma glucose and immunoreactive C-peptide levels were determined in 9 diabetic thalassaemic patients and in 7 controls after arginine infusion. Mean basal and peak values and C-peptide areas in thalassaemic patients did not differ significantly from those of the controls. However, in the thalassaemic group there was a greater variation in values, since pancreatic beta-cell function was found either normal, reduced or increased. These findings could suggest that different factors may lead to diabetes which complicates thalassaemia, i.e. insulin-resistance, probably due to liver damage subsequent to iron deposition and infectious hepatitis, and insulinopenia, probably due to beta-cell lesion following iron storage in the pancreas. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Peptides; Radioimmunoassay; Thalassemia | 1983 |
Beta cell function. Restoration and preservation of B-cells in children with type I diabetes.
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male; Pancreatic Function Tests; Peptides | 1983 |
[The diagnostic value of serum C-peptide determination].
C-peptide and insulin serum determinations were performed in 94 glucagon-stimulated diabetics and in 15 healthy persons. A minimal increase of 1.5 ng C-peptide/ml serum after glucagon injection (1 mg i.v.) was found to be a useful parameter for the differentiation of insulin dependent and non-insulin dependent diabetics. The maximal response to glucagon occurred during the first 10 minutes after the injection (blood was drawn at 2-minutes intervals). Serum insulin levels and basal C-peptide concentrations were of no value in predicting insulin-dependency. Basal C-peptide levels were significantly different from control in juvenile insulin dependent diabetics (decrease) only. Topics: Adolescent; Adult; Aged; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Male; Middle Aged; Peptides | 1983 |
Factors of importance for residual beta-cell function in type I diabetes mellitus. A review.
Topics: Adolescent; Adult; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; HLA Antigens; Humans; Insulin Antibodies; Islets of Langerhans | 1983 |
Proliferative responses to insulin antigens in diabetics and controls.
The proliferative responses of IDDM or NIDDM patients and normal controls to monocomponent pork and beef insulins was assayed over a period of 5 days. No difference was detected in the proliferative responses between the groups. About 25-30% responded to insulin antigens by giving stimulation indices of 1.5 or higher. The exception was the HLA-B8/15 group of patients where no responses (less than or equal to 1.5) were observed. The evidence that the responses detected were insulin specific is discussed, as is the HLA and possible immune response gene linkage. Topics: Adult; Aged; Animals; Antigens; C-Peptide; Cattle; Concanavalin A; Diabetes Mellitus; Diabetes Mellitus, Type 1; HLA Antigens; HLA-B Antigens; Humans; Insulin; Lymphocyte Activation; Middle Aged; Swine; Tuberculin | 1983 |
The effect of glucose, tolbutamide, and arginine on C-peptide release during remission in type I diabetes mellitus.
The insulin secretory capacity was examined in diabetic children at the time of partial clinical remission during which their condition could be managed with low insulin therapy (less than 0.5 U insulin/kg body weight) and no urinary glucose excretion. The extent of the residual beta cell function in 26 children was assessed either by an i.v. arginine test, a combined i.v. glucose-i.v. arginine test, a combined i.v. tolbutamide-i.v. arginine test, or a combined oral glucose-i.v. arginine test determining the C-peptide response by calculating the area under the curve above baseline levels. Two of the children were tested repeatedly. Under the above conditions i.v. glucose and i.v. tolbutamide did not release C-peptide in diabetic children. In contrast, C-peptide secretion during arginine infusion following i.v. glucose or i.v. tolbutamide was significantly enhanced compared to the C-peptide secretion observed during arginine infusion alone. The C-peptide response to oral glucose was sluggish with no effect on the following arginine infusion. The results indicate that during remission in juvenile onset diabetes i.v. glucose and i.v. tolbutamide without themselves being an appropriate signal for C-peptide release amplify the response to a subsequent arginine infusion under appropriate conditions. Topics: Adolescent; Arginine; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Insulin; Male; Tolbutamide | 1983 |
Glucose utilization in Type 1 (insulin-dependent) diabetes: Evidence for a defect not reversible by acute elevations of insulin.
It has long been assumed that replacement of insulin in insulin-deficient diabetic patients will normalise glucose utilization. In this study, glucose utilization was measured in nine long-standing, poorly controlled diabetic patients and five control subjects, matched for age (33 +/- 3 versus 33 +/- 2 years) and ponderal index (22.9 +/- 1.3 versus 21.7 +/- 1.0). Glucose uptake was measured during steady state insulinaemia in the diabetic patients and control subjects, at euglycaemia (5.5 +/- 0.5 versus 5.4 +/- 0.3 mmol/l, respectively) and moderate hyperglycaemia (11.8 +/- 0.9 versus 10.2 +/- 0.7 mmol/l, respectively). At euglycaemia with similar free insulin levels (50 +/- 19 versus 43 +/- 9 mU/l; p greater than 0.6), the diabetic patients utilized less glucose than the control subjects (27.8 +/- 4.2 versus 56.4 +/- 5.7 mumol.kg-1.min-1;.p less than 0.005). During hyperglycaemia, the diabetic patients utilized almost as much glucose as the control subjects did at euglycaemia (49.9 +/- 6.4 versus 56.4 +/- 5.7 mumol.kg-1.min-1, respectively). In the control subjects, a 1-mmol/l rise in glucose concentration (with insulin remaining constant) resulted in a 12.3 +/- 1.3 mumol.kg-1.min-1 rise in glucose utilization. In contrast, in the diabetic patients, a 1-mmol/l rise in blood glucose resulted in a rise in glucose utilization of only 3.8 +/- 0.8 mumol.kg-1.min-1 (p less than 0.001), in the presence of similar concentrations of plasma insulin. This defect of glucose utilization in Type1 diabetic patients could not be reversed by acutely raising insulin to 247 +/- 23 mU/l.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Humans; Insulin; Insulin Resistance; Male; Middle Aged | 1983 |
Pancreatic beta-cell function in tropical pancreatic diabetes.
Individuals with tropical pancreatic diabetes (TPD) have features of malnutrition and insulin-dependent diabetes but do not exhibit ketosis on withdrawal of insulin. Fasting and postglucose C-peptide responses were assessed in TPD and compared with noninsulin-dependent (NIDDM), insulin-dependent (IDDM), and control groups, matched for body weight. The C-peptide concentrations were lower in TPD in comparison with the controls and NIDDM patients but were significantly higher than in classical IDDM. It is likely that the higher C-peptide is responsible for the ketosis resistance in these patients. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Humans; Islets of Langerhans; Middle Aged; Tropical Medicine | 1983 |
[C-peptide determination in type 1 diabetes].
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin | 1983 |
Residual B-cell function in insulin dependent (Type 1) and non insulin-dependent (Type 2) diabetics (relationship between 24-hour C-peptide excretion and the clinical features of diabetes).
Residual B-cell function was studied by measuring 24-hour C-peptide excretion in the urine of 73 Type 1 and 63 Type 2 (28 orally-controlled and 35 insulin-treated) diabetics. Urine C-peptide excretion correlated highly significantly with serum C-peptide concentrations in both the control (r = 0.74, P less than 0.01) and the three diabetic groups (r = 0.89, r = 0.74 and r = 0.89 respectively, P less than 0.001 for all). C-peptide in urine was measurable in 31 of 73 Type 1 diabetics (42%). The earlier the onset and the longer the duration of diabetes, the lower was the proportion of patients with detectable B-cell rest secretion. Preserved residual B-cell function was inversely correlated with the degree of metabolic lability. A significant inverse correlation was also found in this group between 24-hour C-peptide excretion and daily insulin demand (r = 0.78, P less than 0.001). Twenty-nine of the 35 insulin-treated Type 2 diabetics had secondary failure to sulfonylureas and were treated with insulin at the time of the study. Although their daily C-peptide excretion (6.11 +/- 3.71 nmol/24 h) was significantly lower than either the control value (11.30 +/- 0.94 nmol/1, P less than 0.001) or that of orally controlled patients (9.28 +/- 6.16 nmol/l, P less than 0.05) all patients had urine C-peptide concentration in the measurable range. The development of secondary failure to sulfonylureas does not therefore imply complete exhaustion of pancreatic B-cells.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Islets of Langerhans; Male; Middle Aged; Sulfonylurea Compounds | 1983 |
Residual C-peptide production in type I diabetes mellitus. A comparison of different methods of assessment and influence on glucose control.
The aims of the present study were to compare various methods for assessment of residual insulin production and to evaluate its role in the metabolic regulation in insulin-dependent, type I diabetes mellitus. Glycosylated hemoglobin (HbA1) was used as a measure of the long-term glycemic control. Twenty-eight patients with type I diabetes mellitus with onset before the age of 30 and with a duration of less than 6 years were studied. C-peptide in plasma in the fasting state, after glucagon stimulation, and the 24-hour urinary excretion were measured. Fasting plasma C-peptide was detected in 61%, and 39% showed a significant rise after glucagon stimulation. The increment correlated negatively with HbA1 (rs = -0.57, p less than 0.001), as did the 24-hour urinary excretion (rs = -0.61, p less than 0.001). The 16 patients with urinary C-peptide values of at least 1 nmol had a mean HbA1 of 8.9 +/- 0.3%, as opposed to 11.6 +/- 0.5% for those excreting less (p less than 0.001). Measurement of the 24-hour urinary excretion of C-peptide provides a reliable method for evaluating residual insulin secretion. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Lipids; Male | 1983 |
Ultrastructural, immunohistological, and clinical findings in the pancreas in insulin-dependent diabetes mellitus (IDDM) of long duration.
Electron microscopical and immunohistological findings in small biopsies obtained at surgery from two subjects with longstanding type-I-diabetes [insulin-dependent diabetes mellitus (IDDM)] are described and demonstrated in relation to clinical data. The main findings are the first electron microscopical demonstration of A cells scattered as single cells in the exocrine pancreatic tissue and the detection of intermediate cells of the acinar-A cell type. Intermediate cells have never been reported before in the pancreas of diabetes in man. Topics: Aged; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Humans; Islets of Langerhans; Male; Microscopy, Electron; Middle Aged; Pancreas | 1983 |
Serum C-peptide levels in young ketosis-resistant diabetics.
Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Insulin; Male | 1983 |
Renal function in relation to metabolic control in children with diabetes of different duration.
To evaluate the interpretation of different kidney function tests in diabetic children and teenagers we have studied 47 children with a duration of diabetes up to 5 years, 61 children with a duration of 5.1-10 years and 49 children with a duration of greater than 10 years. Glomerular filtration rate (GFR) measured as inulin clearance or creatinine clearance, clearance PAH (CPAH), filtration fraction (FF), 24-hour urinary excretion of beta 2-microglobulin and albumin were examined and correlated with short- and longterm indices of metabolic control. In all groups of duration GFR as measured by inulin clearance was increased compared with reference values from age matched controls. In patients who had had diabetes for 0-5 years a significant positive correlation was found between inulin clearance and blood glucose during the examination. Inulin clearance was also correlated to HBA1c as well as to 24-hour urinary glucose (mean of 4-6 samples during two years). No such correlation was found in the group who had had diabetes for 5-10 years but in patients with a duration of diabetes greater than 10 years a significant inverse relation was found between GFR and HbA1c. The 24-hour urinary excretion of albumin was significantly higher in all groups of diabetics compared with controls. The urinary excretion of beta 2-microglobulin was similar in diabetics and controls. In the total material no significant correlation could be found between inulin clearance and creatinine clearance.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Adolescent; Adult; Albuminuria; beta 2-Microglobulin; Blood Glucose; C-Peptide; Child; Creatinine; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Glomerular Filtration Rate; Glycosuria; Humans; Hydroxybutyrates; Kidney; Prospective Studies | 1983 |
The improved response in endogenous insulin due to continuous subcutaneous infusion of insulin therapy in juvenile diabetes.
We investigated the relationship between the recovery or improved response of endogenous insulin and the control of blood glucose in juvenile diabetes (IDDM) treated with the continuous subcutaneous infusion of insulin (CSII). (1) It is unlikely that the decrease in endogenous insulin secretion over several years following onset of IDDM in 43 subjects was uniform in terms of urinary c-peptide (u-CPR) excretion. (2) In 27 newly diagnosed cases of IDDM, the group receiving CSII (n = 18) showed more satisfactory results, including greater stability of blood glucose, a more rapid decrease in insulin requirements and an earlier improvement in u-CPR compared to the control group who were receiving conventional subcutaneous insulin therapy (n = 9). (3) U-CPR increased with the improvement in blood glucose control within 2 to 4 wks of the initiation of CSII in 6 of 8 already-treated cases of IDDM, while daily insulin requirements did not differ significantly before and after CSII. Since short-term CSII therapy improved u-CPR response by normalizing blood glucose not only in newly diagnosed but also known diabetic, therapy should be directed toward the long-term intensive control of blood glucose in order to maintain the potency of endogenous insulin secretion especially in newly-diagnosed cases of insulin secretion especially in newly-diagnosed cases of IDDM. Topics: C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Infusion Systems; Male | 1983 |
Clinical usefulness of artificial endocrine pancreas "Biostator" in management of unstable diabetics.
The diurnal blood glucose profiles of 15 unstable diabetics were continuously monitored by the artificial endocrine pancreas (AEP, Biostator). Then, feedback control (FC) with the AEP was performed on each subject for 24-32 hr. Based on the data obtained from FC, the patients received an intensified conventional insulin therapy (ICIT) consisting of two daily mixed injections, 45-60 min prior to meals. There was a negative correlation between the MAGE and the sum of serum CPR in a 50 g OGTT, before FC. The M-value, MBG and MAGE decreased significantly during FC and remained lower one month later, compared with those values obtained before FC. The ICIT caused a noticeable decrease in HbA1 levels one to four months after FC. The ICIT was characterized by an increase in the proportion of short-acting insulin in the daily insulin dosage to 40. 3 +/- 11.5%. The proportion of daily insulin dosage to body weight also increased to 0.73 +/- 0.17 U/kg. These results suggest that the AEP, Biostator, could be useful in the clinical management of unstable diabetics by providing a more precise estimate of patients insulin requirements, especially those of short-acting insulin, leading to a better long-term control of blood glucose. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Insulin; Insulin Infusion Systems; Male; Middle Aged | 1983 |
Plasmapheresis in the initial treatment of insulin-dependent diabetes mellitus in children.
Several factors indicate that autoimmune mechanisms may play a part in the aetiology of insulin-dependent diabetes mellitus. At the onset of the disease in 10 children (aged 11-16 years) plasmapheresis was performed four times over one to two weeks. Seventeen age-matched children with the same clinical features served as controls. The C-peptide concentrations at onset were the same in the two groups, but after one month the children treated with plasmapheresis had significantly higher values. This difference became even more pronounced after three, nine, and 18 months, both during fasting and at the maximum response to a standardised meal. The study group also had a significantly more stable metabolism, longer partial remission, and no higher insulin requirement. Of the 10 treated children islet-cell cytoplasmic antibodies were present in seven before plasmapheresis and in nine during treatment. The antibodies remained detectable in five and six out of nine patients at one and six months respectively after plasmapheresis. Although the mechanisms are obscure, plasmapheresis performed at the onset of insulin-dependent diabetes mellitus may help to preserve beta-cell function. Topics: Adolescent; Autoantibodies; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male; Plasmapheresis; Time Factors | 1983 |
Allotransplantation of neonatal pancreas-microfragments in man.
We report of an allotransplantation of neonatal pancreatic tissue. The donor was a three-week-old girl with nesidioblastosis, in which a subtotal pancreas resection had to be performed. The pancreas microfragments were injected transcapsularly into the spleen of a patient with juvenile diabetes. During the postoperative course only a short-termed improvement of the diabetic condition was seen. Topics: Antilymphocyte Serum; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Infant, Newborn; Insulin; Islets of Langerhans Transplantation; Male; Middle Aged; Pancreatic Diseases | 1983 |
In vitro lymphocyte proliferation response to therapeutic insulin components. Evidence for genetic control by the human major histocompatibility complex.
Genes in the major histocompatibility complex of mice and guinea pigs control immunologic responsiveness to insulins from other animal species. In order to determine if similar genetic control exists in man, we have examined lymphocyte proliferation responses to components of therapeutic insulins by employing lymphocytes from diabetic patients that receive insulin. Distinct groups of individuals demonstrated positive lymphocyte proliferative responses to beef insulin, beef and pork insulin, beef proinsulin, pork proinsulin, and protamine. Lymphocytes from the patient population were typed for the HLA-A, B, C, and DR antigens. An increased frequency of certain HLA antigens was found in those individuals that responded to the following therapeutic insulin components: beef, HLA-DR4; beef and pork, HLA-DR3; beef proinsulin, HLA-BW4, CW2, CW5, DR2, and DR5; protamine, HLA-CW3, CW5, and DR7. The results demonstrate that the human immune system recognized the structural differences between human and beef and/or pork insulin. These differences are two amino acids in the A chain, alpha loop, of beef insulin and the single terminal amino acid, alanine, which is common to pork and beef insulins. Positive responses to both beef proinsulin and pork proinsulin demonstrated the capability of restricted recognition of more complex proteins represented by the C-peptide in these insulin preparations. Lymphocyte proliferative responses to protamine were also restricted, which suggests a genetic control to this antigen. The association of these responses with HLA alloantigens strongly suggests that genes within the human major histocompatibility complex control recognition and lymphocyte response to therapeutic insulin components. Topics: Adult; Amino Acid Sequence; Animals; Antigens; C-Peptide; Cattle; Diabetes Mellitus, Type 1; Genes, MHC Class II; Guinea Pigs; Histocompatibility Antigens Class II; HLA Antigens; HLA-DR Antigens; Humans; Insulin; Lymphocyte Activation; Middle Aged; Proinsulin; Protamines; Swine | 1983 |
Abnormal regulation of sympathetic nervous activity and heart rate after oral glucose in type 1 (insulin-dependent) diabetic patients.
Oral glucose administration increased plasma noradrenaline concentration significantly in seven normal subjects (p less than 0.02), whereas in six young short-term Type 1 diabetic patients without complications plasma noradrenaline did not change. Basal plasma noradrenaline did not differ between the two groups. In the first 3 h after oral glucose administration, the mean heart rate in eight normal subjects was increased 3.5% above basal levels (p less than 0.05). In contrast, no such increase was found in eight Type 1 diabetic patients after glucose administration. In two normal subjects thoroughly examined before and after oral glucose administration, we observed a significant correlation between heart rate and systolic blood pressure (p less than 0.001) but this was not seen in two diabetic patients in whom neither heart rate nor systolic blood pressure increased. Our findings indicate that sympathetic nervous activity and cardiovascular function is abnormal in early diabetes during an oral glucose load. Topics: Adolescent; Adult; Blood Pressure; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucose; Heart Rate; Humans; Male; Norepinephrine; Stimulation, Chemical; Sympathetic Nervous System; Tachycardia | 1983 |
[Comparative studies between median blood sugar, hemoglobin A, triglycerides and C-peptide in normal-weight insulin and non-insulin dependent diabetics].
In our study the glycosylated haemoglobin was positively correlated with the mean bloodglucose concentration and the levels of serum triglycerides and proved to be a valuable parameter, which completes the hitherto existing possibilities of diabetes control. The difference of the levels of serum triglycerides and C-peptide between non-insulin-dependent and insulin-dependent diabetics, with the same quality of the levels of HbA 1 and mean bloodglucose, give us a help to decide, which therapeutic way would be the best in the introduction respectively correction of the treatment of the elderly diabetic patients. Topics: Blood Glucose; Body Weight; C-Peptide; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Hemoglobin A; Humans; Male; Middle Aged; Triglycerides | 1983 |
Long-term insulin-dependent diabetes mellitus with secondary pituitary insufficiency and regression of retinopathy.
Three women with insulin-dependent diabetes mellitus (IDDM) from childhood and early development of diabetic retinopathy are described. Insulin requirement was reduced to 5-12 IU daily in all three after relatively uncomplicated births and all had very brittle diabetes on this dosage. At re-examination 16-22 years after these births and after 34-42 years of IDDM, regression of retinopathy was observed in two patients, while the third had a light retinopathy at the same level as initially. Other diabetic complications were few and none of the patients had nephropathy. Pituitary examination revealed incomplete hypopituitarism in all cases, human growth hormone (HGH) being the sole common factor lacking. These findings and a review of four similar cases reported previously lend some support to the hypothesis of HGH as a possible pathogenetic co-determinant in the development of diabetic retinopathy. Topics: Adult; C-Peptide; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Humans; Hypopituitarism; Middle Aged; Pituitary Function Tests; Pituitary Hormones, Anterior; Remission, Spontaneous; Thyroid Hormones; Time Factors | 1983 |
Diabetes in tropics--perspectives of research.
HLA antigen studies indicate heterogeneity of allele of B locus and propedine factor based on racial differences, while confirming specificity of DR3-DR4 for IDDM. C-peptide reserve is indicative of some sparing of beta cell destruction due to pre-existing nutritional state with enzymatic modulations modifying ketosis in the atypical IDDM in North India. Specific diabetic vascular disease has lesser geographical predisposition though factors that promote its severity or restrain its progress are not well understood. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Angiopathies; HLA Antigens; Humans; India | 1983 |
[Importance of plasma C-peptide evaluation during the oral glucose tolerance test in infantile and juvenile obesity].
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; Obesity; Peptides | 1983 |
Whole foods and increased dietary fibre improve blood glucose control in diabetic children.
In prescribing a diabetic diet more attention has traditionally been paid to the amount of dietary carbohydrate than to its type or structure. We have compared the effect on blood glucose of substituting unrefined, whole foods for refined, processed foods in liberal carbohydrate diets (50-55% of dietary energy) eaten by 10 diabetic children in a randomised crossover study. All measurements were made at home. The unrefined diet used whole foods (including) dried beans) supplying 60 g/day of dietary fibre. The refined diet used processed foods supplying 20 g/day of dietary fibre. Diets were isocaloric for carbohydrate, fat, and protein. Glycaemic control was assessed by daily urine analysis for glucose, home blood glucose measurements, glycosylated haemoglobin, and by a 24-hour profile of blood and urinary glucose carried out at home after 6 weeks on each diet. Glycaemic control was significantly better on the unrefined diet. On profile days mean blood glucose levels on the unrefined and refined diets respectively were: preprandial: 5.5 and 8.4 mmol/l; postprandial 8.5 and 12.2 mmol/l. The mean 24-hour urinary glucose excretion on the unrefined diet was 9.3 g and on the refined diet was 38.0 g. Six months after the study the children were eating appreciably more dietary fibre than before (mean increase 13.6 g/day). Attention to food type and structure can improve blood glucose control in diabetic children and should provide an acceptable and more rational basis for dietary prescription than one based on carbohydrate quantity alone. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Dietary Fiber; Female; Glycosuria; Humans; Hypoglycemia; Insulin; Male; Patient Acceptance of Health Care; Patient Compliance | 1982 |
[Roles of endogenous insulin reserve and the counter-regulatory hormones in the various phases of juvenile diabetes mellitus].
Topics: Adolescent; Age Factors; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Hydrocortisone; Insulin; Insulin Secretion | 1982 |
Postinitial remission in diabetic children--an analysis of 178 cases.
We studied 178 diabetic children and adolescents diagnosed during the period 1962-79 to find out the occurrence and duration of the postinitial remission, factors favoring a remission and the prognostic value of the remission. A postinitial remission occurred in 113 children (64%) being complete in only three boys (2%). The duration ranged from one month to 4.8 years, the mean being 8.4 months. The boys had a remission more often and of longer duration than the girls. The duration of diabetes was longer in the children without remission. The children with remission had lower blood glucose, milder hyperketonemia and ketonuria, higher pH and PCO2 at onset than those without remission. Hemoglobin A1 (HbA1) during 1979 were lower in the children with a positive remission history. The children with a remission lasting more than one year had a subsequently higher glucosuria index, lower HbA1 and higher C-peptide when compared to those without remission or to those with a short remission. The remission frequency increased from 1962 to 1979. Male sex and mild metabolic derangement at onset favor a postinitial remission, which results in a persisting residual beta-cell function and better metabolic control beyond the remission. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Hemoglobin A; Humans; Infant; Insulin; Ketone Bodies; Male; Remission, Spontaneous; Time Factors | 1982 |
Is there a relationship between islet cell surface antibodies and clinical, biochemical, hormonal, and immunogenetic parameters in newly diagnosed type I diabetics?
Topics: Adolescent; Adult; Aged; Antibodies; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; HLA Antigens; Humans; Islets of Langerhans; Ketone Bodies; Male; Middle Aged | 1982 |
Insulin resistance and diabetes due to a genetic defect in insulin receptors.
A 14-yr-old woman presented with fasting hyperglycemia (269 mg/dl), fasting hyperinsulinemia (45 microU/ml), acanthosis nigricans, and insulin resistance. The patient's circulating insulin was normal by physical and biological criteria, and insulin receptor antibodies were not detected. Both the patient's in vivo dose-response curve for insulin-stimulated glucose transport in isolated adipocytes were shifted to the right and showed marked decreases in the maximal insulin response. Basal hepatic glucose output was significantly increased, and the in vivo dose-response curve for insulin-mediated suppression of basal hepatic glucose output was shifted to the right. Insulin binding to the patient's erythrocytes, monocytes, and adipocytes was markedly decreased. To confirm that the severe reduction in cellular insulin receptors was a primary rather than an acquired defect, similar studies were conducted using cultured fibroblasts. No detectable binding of insulin to these cells was observed. Further studies showed that the patient's mother and two sisters were hyperinsulinemic and insulin resistant, and had comparable, although less severe, changes in insulin binding. The patient was also demonstrated to have an insulin secretory defect both to both oral and iv glucose challenges. We thus conclude that this family demonstrates a genetic deficiency of insulin receptors, resulting in insulin resistance and, in this patient, severe diabetes mellitus. Topics: Adipose Tissue; Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fasting; Female; Glucose Tolerance Test; Growth Hormone; Humans; Insulin; Insulin Resistance; Liver; Proinsulin; Receptor, Insulin | 1982 |
Permanent neonatal diabetes in an infant of an insulin-dependent mother.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Infant, Newborn; Insulin; Male; Receptor, Insulin; Tolbutamide | 1982 |
Endocrine pancreatic response of children with onset of insulin-requiring diabetes before age 3 and after age 5.
The increased incidence of severe hypoglycemia reported in young children with diabetes is consistent with a defect in glucagon secretion or a generalized abnormality in islet hormone secretion. To assess pancreatic hormone and gastric inhibitory polypeptide secretion in children with early onset diabetes, 12 children with onset of diabetes prior to the age of 28 months were studied and the data compared to the hormone responses observed in 11 children with LOD, diagnosed after the age of 5 years. Plasma glucose, C-peptide, glucagon, pancreatic polypeptide, and gastric inhibitory peptide concentrations were measured during and following an arginine infusion (500 mg/kg over 60 minutes) and a mixed meal. During arginine infusion, plasma glucose and glucagon increased similarly in both groups and returned to basal concentrations following discontinuation of arginine infusion. In contrast, plasma C-peptide, hPP, and GIP concentrations did not change. Following the mixed meal plasma glucose, hPP, and GIP concentrations increased similarly in the two groups of children, but no change was observed in either plasma glucagon or C-peptide concentrations in either group. These data demonstrate that EOD and LOD are associated with insulin insufficiency alone and that abnormalities in secretion of other pancreatic islet hormone or GIP cannot be implicated in the high incidence of severe hypoglycemia observed in children with EOD. Topics: Arginine; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Gastric Inhibitory Polypeptide; Glucagon; Humans; Hypoglycemia; Infant; Infusions, Parenteral; Insulin; Islets of Langerhans; Male; Pancreatic Polypeptide; Time Factors | 1982 |
Twenty-four hour profiles of plasma C-peptide in type 1 (insulin-dependent) diabetic children.
Twenty-four hour profiles of plasma C-peptide, an index of endogenous insulin secretion, were performed in 15 Type 1 (insulin-dependent) diabetic children. Plasma C-peptide was detectable in six children, of whom four ('C-peptide producers') had peak values above normal fasting levels. In each of the six children with residual B cell function, there was a close correlation between plasma C-peptide and simultaneous blood glucose (r greater than 0.50, p less than 0.05). Post-breakfast peak blood glucose was 10.2 +/- 1.7 mmol/l (mean +/- SEM) in the 'C-peptide producers' and 18.7 +/- 1.7 mmol/l in the 11 children with low or no detectable C-peptide. Mean M-value, an index of deviation from an ideal blood glucose, was lower in the 'C-peptide producers' (p less than 0.05). It is concluded that residual functioning B cells in diabetic children behave physiologically in that insulin secretion fluctuates in accordance with the prevailing blood glucose; and that the pattern of action of injected insulin is more critical in non-C peptide producers who lack the post-prandial dampening effect provided by residual endogenous insulin secretion. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Peptides | 1982 |
Correlation between fasting serum C-peptide and B cell insulin secretory capacity in diabetes mellitus.
Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Fasting; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Middle Aged; Peptides | 1982 |
[C-peptide excretion in 24 hours-urine as an indicator of B-cell residual function in children and adolescents with type-I-diabetes (author's transl)].
In 140 juvenile diabetics residual B-cell-function was measured according to the amount of the immunoreactive C-peptide (IRCP) in the 24 h-urine. We were able to repeat this test after two years in 69 of these patients. All diabetic children showed maintained residual insulin secretion (mean +/- S mean 2.60 +/- 0.31 nmol/24 h). There was a significant negative relationship (p less than 0.001) between the duration of diabetes and the extend of the residual B-cell-function. C-peptide urine excretion of the diabetics who were followed up dropped significantly (0.08 down to 0.02 nmol/kg/24 h, p less than 0.001), and the daily insulin requirement increased significantly (0.36 to 0.67 U/kg, p less than 0.05). In comparison, children with a shorter duration of the diabetes (less than 3 years) showed a more rapid decrease of their residual B-cell function with a simultaneously greater increase of the daily insulin dose as opposed to children with the diabetes for longer than 3 years at the time when they were first seen. With a short course of diabetes the decrease of the C-peptide and the increase of the daily insulin dose were negatively correlated (p less than 0.001). The clinical phenomena of the remission period as known until now are related to the decline of B-cell function. Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Male; Peptides; Time Factors | 1982 |
[On C-peptide and some other parameters in children with insulin dependent diabetes mellitus (author's transl)].
C-peptide and some other parameters have been evaluated in 62 patients (31 male, 31 female) with insulin dependent diabetes mellitus in respect to quality of diabetic control. C-peptide was negatively correlated to duration of diabetes as was duration of initial remission with insulin requirements. Duration of initial remission was correlated positively to quality of diabetic control. The correlations of C-peptide with quality of diabetic control, insulin requirements and duration of initial remission were statistically not significant; insulin requirements and quality of diabetic control were not correlated significantly. From the results it is concluded that for the quality of diabetic control and hence the long-term course in patients with insulin dependent diabetes mellitus the duration of initial remission as a result of the quality of initial treatment is of the utmost importance. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Male; Peptides; Prognosis; Time Factors | 1982 |
Insulin levels in amniotic fluid and fetal growth.
Insulin concentrations in amniotic fluid were correlated with fetal age and with fetal weight in order to test the hypothesis that fetal insulin regulates fetal growth. No significant correlation could be detected. Insulin levels in amniotic fluid in diabetics, however, were significantly higher than in nondiabetics. In the same samples of amniotic fluid C-peptide proved to be very unstable during long term storage. Topics: Amniotic Fluid; C-Peptide; Diabetes Mellitus, Type 1; Female; Fetus; Gestational Age; Growth; Humans; Infant, Newborn; Infant, Small for Gestational Age; Insulin; Pregnancy; Pregnancy in Diabetics | 1982 |
[Residual insulin secretion in juvenile diabetes. Relationships with duration of diabetes, metabolic control and retinopathy (author's transl)].
This study concerned 74 diabetic children and adolescents, ages ranging from 3 to 21 years. Duration of the disease ranged from 1 month to 15 years. Blood samples were taken during a 12 month period of observation. 292 immunoreactive C-peptide (CPR) evaluations showed a residual endogeneous secretion of insulin in 57% of cases. CPR and duration of diabetes were negatively correlated (r = -0.35; p less than 0.01); however, even 5 years after onset of the disease, a residual beta-cell activity could be observed. CPR was not related with blood glucose, triglyceride, cholesterol or glycosylated hemoglobin levels. On the other hand, CPR was statistically higher in patients whose diabetes had been well-controlled from the onset of the disease, according to clinical criteria, and in those who did not present with retinopathy: however they were also the patients with the shortest duration of disease. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Humans; Insulin; Insulin Secretion; Time Factors | 1982 |
Factors influencing residual pancreatic beta cell function in recently diagnosed Type 1 diabetic children.
Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Islets of Langerhans; Male | 1982 |
[Application of artificial endocrine pancreas. - Improvement in insulin secretory ability and normalization of metabolic and endocrine disorders in diabetic subjects].
Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin Infusion Systems | 1982 |
[The occurrence of proinsulin and C-peptide in healthy humans and in diabetics].
Chemistry, biochemistry and physiology of proinsulin and C-peptide are summarized. A short characterization of the radioimmunological methods for measuring C-peptide and proinsulin follows. The determination of C-peptide and proinsulin which was mainly carried out in serum or plasma essentially improved our knowledge about the function of the beta-cells in the islets of Langerhans in healthy subjects and diabetic patients. The paper reports on the occurrence and the course of C-peptide and proinsulin in healthy subjects and in diabetics of type I and II. Topics: Adult; Amino Acid Sequence; Blood Glucose; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Peptides; Proinsulin; Radioimmunoassay | 1982 |
Partial preservation of pancreatic beta-cell function in children with diabetes.
Topics: Adolescent; Autoantibodies; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male; Prednisone; Secretory Rate | 1981 |
Permanent remission of ketotic diabetes with subsequent normal C-peptide secretion.
Topics: Adolescent; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Male; Peptides | 1981 |
Nonketotic hyperosmolar coma in two diabetic children.
Two diabetic children with nonketotic hyperosmolar coma were treated successfully. In one of the patients, plasma-free fatty acids, insulin, C-peptide and two lipolytic hormones (growth hormone and cortisol) were measured serially during the coma. Free fatty acids, insulin, C-peptide, growth hormone and cortisol levels were within normal ranges and subsequently these levels did not change significantly. The results suggest that the normal levels of lipolytic hormones may account for the normal plasma free fatty acids and the absence of ketosis found in children with nonketotic hyperosmolar coma, in contrast to the elevated levels of lipolytic hormones and ketone bodies in ketoacidotic diabetic coma. Topics: C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Coma; Fatty Acids, Nonesterified; Growth Hormone; Humans; Hydrocortisone; Hyperglycemic Hyperosmolar Nonketotic Coma; Insulin; Male | 1981 |
Very early changes in circulating T3 and rT3 during development of metabolic derangement in diabetic patients.
Alterations in circulating iodothyronines were studied in 15 juvenile type diabetic patients during the development of metabolic derangement after withdrawal of insulin. By means of measurements of circulating C peptide, one group of patients with and one without residual beta-cell function had been selected. In both groups there was a gradual decrease in serum T3 during the 12-hour period studied after withdrawal of insulin, while an increase in serum rT3 was observed after 4-6 hours. The alterations in serum T3 and the metabolic derangement were significantly more pronounced in patients without than with residual beta-cell function. Topics: C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Islets of Langerhans; Time Factors; Triiodothyronine; Triiodothyronine, Reverse | 1981 |
The effects of equal caloric amounts of xylitol, sucrose and starch on insulin requirements and blood glucose levels in insulin-dependent diabetics.
Xylitol has been suggested as a potentially useful sweetener in the diabetic diet. In 14 insulin-dependent diabetics a standard diabetic diet regimen was compared with diets in which starch was isocalorically exchanged in the breakfast meal by either 30 g xylitol or 30 g sucrose. Insulin requirement and blood glucose were measured using a glucose-controlled insulin infusion system. The results following breakfast with xylitol were similar to those after starch breakfasts. Sucrose, in contrast, induced a greater post-prandial rise in blood glucose levels despite counter-regulation by the glucose-controlled insulin infusion system. Insulin requirement after sucrose significantly exceeded (p less than 0.01) that after xylitol or starch during the first 60 min and 2 h respectively. No short-term side effects of xylitol were found. Topics: Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Dietary Carbohydrates; Energy Intake; Humans; Insulin; Starch; Sucrose; Xylitol | 1981 |
[Plasma insulin in normal children and in diabetic children treated with intramuscular injections of insulin (author's transl)].
Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Injections, Intramuscular; Insulin; Male | 1981 |
Relationship of glycosylated haemoglobin to C-peptide secretory status and antibody binding of insulin in insulin-dependent diabetes.
Diabetic control, assessed by measuring the concentration in venous blood of total glycosylated haemoglobin (HbA1), endogenous insulin secretion, as estimated by the C-peptide response (delta C-P) to intravenous glucagon, and serum beef insulin antibody binding were measured in 50 juvenile onset insulin dependent diabetics (IDDM) receiving a single daily injection of soluble and protamine zinc insulin. The delta C-P correlated inversely with duration of diabetes (tau = -0.27, p less than 0.01) and daily insulin requirement (tau = -0.22, p less than 0.05) in the 50 IDDM studied of whom 28 exhibited a measurable delta C-P. In C-peptide nonresponders, but not in the C-peptide responders, and inverse regression (t = 2.19, p less than 0.05) was observed between beef insulin antibody and HbA1. In the 25 IDDM having the lowest insulin antibody binding, and inverse correlation (tau = 0.36, p less than 0.02) was observed between delta CP and HbA1, which was not found (tau = 0.05) in the remaining 25 IDDM who had the highest insulin antibody binding. These findings suggest that, in the absence of endogenous insulin secretion, diabetic control in IDDM receiving a single daily injection of conventional beef insulin is better in patients with high beef insulin antibody binding. Conversely, in patients with low beef insulin antibody binding, diabetic control appears to be better in those with persisting endogenous insulin secretion. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Female; Glucagon; Glycated Hemoglobin; Humans; Insulin; Insulin Antibodies; Male; Peptides | 1981 |
Effects of pharmacologic hyperglucagonemia on plasma amino acid concentrations in normal and diabetic man.
Four normal and five insulin dependent diabetic men received a 2 h pharmacologic glucagon infusion (50 ng/kg/min) resulting in plasma glucagon levels (4400 pg/ml) similar to those seen in glucagonoma patients. In normal subjects in whom plasma insulin concentrations rose significantly (239 uU/ml) and the blood level of 15 of the 18 amino acids measured fell significantly. In contrast, in the diabetic men who secreted no insulin in response to glucagon (no rise in C-peptide levels), only 10 of 18 amino acid levels fell significantly. The branched chain amino acids valine, leucine and isoleucine, as well as tyrosine and phenylalanine were among the 8 amino acids which showed no change in response to glucagon in the diabetics. Thus, glucagon appears to have no acute affect on branched chain amino acid levels in man. Topics: Amino Acids; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Glucagon; Humans; Insulin; Male; Time Factors | 1981 |
[Function of the islands of Langerhans and the course of diabetes mellitus in children].
Topics: C-Peptide; Child; Child, Preschool; Cholesterol; Diabetes Mellitus, Type 1; Glutamate Dehydrogenase; Humans; Insulin; Islets of Langerhans | 1981 |
[Plasma C-peptide levels in juvenile diabetes].
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Drug Therapy; Glucose; Humans; Insulin; Peptides | 1981 |
B-cell secretion in non-diabetics and insulin-dependent diabetics.
Topics: C-Peptide; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Insulin; Islets of Langerhans; Proinsulin; Radioimmunoassay | 1981 |
[beta-Cell residual function in juvenile diabetes mellitus (author's transl)].
Estimation of C-peptide (IRCP) can be used to measure the residual beta-cell function in insulin treated diabetics. IRCP was estimated in 46 juvenile diabetics. A significant correlation between basal IRCP-levels and duration of diabetes as well as daily insulin requirement could be shown. There was no linear correlation between glucosuria and IRCP. However, patients with IRCP > 1,0 ng/ml had significantly lower glucosuria ( p < 0,005). Endogenous residual function of the beta-cells seems to be of importance for metabolic control in diabetic children. Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Insulin; Islets of Langerhans; Male; Mathematics; Time Factors | 1980 |
Effects of exogenous insulin on excursions and diurnal rhythm of plasma glucose in pregnant diabetic patients with and without residual beta-cell function.
Topics: Adult; Blood Glucose; C-Peptide; Circadian Rhythm; Diabetes Mellitus, Type 1; Female; Humans; Infant, Newborn; Insulin; Insulin Resistance; Pregnancy; Pregnancy in Diabetics; Pregnancy Trimester, Second; Pregnancy Trimester, Third; Receptor, Insulin | 1980 |
C-peptide response to arginine stimulation in diabetic children.
The extent and the clinical significance of residual beta cell function has been evaluated by radioimmunoassay of C-peptide in 41 diabetic children in different stages of evolution, using an arginine tolerance test. In control subjects a significant rise of C-peptide levels occurred after the infusion with arginine. In patients at the onset of the disease and in patients not in the remission stage, C-peptide levels showed no increment and basal values were significantly lower than in healthy control children. Children during the remission phase showed basal and peak values not significantly different from controls. A positive correlation was found between highest CPR levels compared to basal CPR values and to the age at onset of diabetes; a negative correlation was found between the duration of the disease and insulin requirement. Topics: Arginine; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male; Peptides; Radioimmunoassay; Remission, Spontaneous | 1980 |
Islet-cell antibodies and beta-cell function in insulin-dependent diabetics.
Residual insulin secretion and islet-cell antibodies were studied in 399 insulin-dependent diabetics with age at onset of between 10--19.9 years (248 patients) or 30--39.9 years (151 patients). We found the prevalence of islet-cell antibodies to be independent of residual beta-cell function as measured by serum C-peptide and age at onset. The cause and role of the persistence of islet-cell antibodies in insulin-dependent diabetics remain obscure. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans | 1980 |
Effects of acetylsalicylic acid on blood glucose, plasma FFA, glycerol, 3-hydroxybutyrate, alanine, C-peptide, glucagon and growth hormone responses to arginine in insulin-dependent diabetics.
This study aimed at evaluating the effect of acetylsalicylic acid (ASA) on blood glucose, plasma FFA, glycerol, 3-hydroxybutyrate, alanine, C-peptide, glucagon and growth hormone responses to arginine in subjects with insulin-dependent diabetes. For this purpose, seven insulin-requiring diabetics were submitted to a standard arginine tolerance test before and after a three day treatment with ASA (50 mg/kg/daily, plus 1 g before the second test). ASA treatment resulted in no significant changes in either basal or arginine-stimulated blood glucose, but it significantly decreased the basal concentrations of plasma FFA (p less than 0.05), 3-hydroxybutyrate (p less than 0.05) and glycerol (p less than 0.05). In addition, the fall in plasma FFA concentrations during arginine infusion was significantly less after ASA than levels observed without ASA (--262 +/- 100 microEq/l vs --35 +/- 57 microEq/l, p less than 0.02). No significant changes in either basal or arginine-stimulated glucagon concentrations were observed after ASA; by contrast, the growth hormone peak was significantly reduced after ASA (11.3 +/- 4.2 ng/ml vs 5.1 +/- 1.1 ng/ml, p less than 0.05). These metabolic effects exerted by ASA in insulin-dependent diabetes seem not to be related to alterations in endogenously secreted insulin since C-peptide circulating levels were similar during the pre- and post-treatment arginine tests. Topics: Adolescent; Adult; Alanine; Arginine; Aspirin; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Glucagon; Glycerol; Growth Hormone; Hormones; Humans; Hydroxybutyrates; Insulin; Male; Middle Aged | 1980 |
Beta-cell function and metabolic control in insulin treated diabetics.
In a random one day study beta-cell function was evaluated in 210 insulin treated diabetics by the serum C-peptide concentration 6 min after iv injection of 1 mg of glucagon. Sixty-five patients (31%) had residual beta-cell function. As a group these patients were characterized by having a higher age at onset of diabetes (P less than 0.01), a shorter duration of disease (P less than 0.01) and by receiving a smaller dose of insulin (P less than 0.01). However, their quality of metabolic control did not differ from the patients without beta-cell function. Although the concentrations of post-stimulatory C-peptide correlated inversely with both the 24-hour glycosuria (P less than 0.01) and the fasting blood glucose concentrations (P less than 0.02), only a subgroup with C-peptide concentrations exceeding 0.30 pmol/ml showed a definitely better degree of metabolic control than those without beta-cell function. As this subgroup also received the smallest dose of insulin these observations suggest that maintenance of beta-cell function above this level facilitates good metabolic control. Evidence is presented suggesting that measurements of the 24-hour glycosuria undertaken in a diabetes clinic create a too optimistic impression of the quality of metabolic control during every day life. Topics: Adolescent; Adult; Aged; Blood Glucose; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glycosuria; Humans; Insulin; Islets of Langerhans; Male; Middle Aged | 1980 |
[Insulin and C-peptide in the blood serum of children and adolescents with diabetes mellitus].
Topics: Adolescent; Arginine; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Antibodies; Peptides | 1980 |
Measurement of serum C-peptide immunoreactivity by radioimmunoassay in insulin-dependent diabetics.
A radioimmunoassay for C-peptide utilizing synthetic C-peptide as an antigen and tyrosylated synthetic C-peptide for iodination was evaluated for its clinical use. Mean fasting C-peptide levels in 24 normal subjects was 2.6 +/- 0.8 ng/ml. During the oral glucose tolerance test, baseline C-peptide in five normal subjects was 1.5 +/- 0.8 ng/ml, and at 60 min was 5.6 +/- 1.6 ng/ml. For two insulin-dependent diabetic patients, diagnoses of factitious hypoglycemia were documented on the basis of simultaneous free insulin and C-peptide determinations. Sera from 24 insulin-dependent diabetics were analyzed for free and total immunoreactive C-peptide and insulin levels. For 20% of juvenile and 64% of maturity-onset diabetics, the presence of proinsulin-like material bound to insulin antibodies was demonstrated by measurement in unextracted serum. This accounted for 20% to 100% of total C-peptide immunoreactivity in these patients. Simple polyethylene glycol precipitation of immune complexes and the measurement of free immunoreactive C-peptide in the supernatant demonstrated subnormal levels (less than 0.5 ng/ml) in all juvenile diabetics and normal levels (1.8 +/- 1.3 ng/ml) in 70% of maturity-onset diabetics. Topics: Adolescent; Adult; Antigen-Antibody Complex; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Hypoglycemia; Insulin; Insulin Antibodies; Peptides; Radioimmunoassay | 1980 |
C-Peptide reserve in insulin-dependent diabetes. Comparative responses to glucose, glucagon and tolbutamide.
Residual beta cell secretory capacity was assessed in short term (2 months to 2 years) and long term (5 to 8 years) insulin-dependent diabetics by measurement of serum C-peptide immunoreactivity during three provocative tests: glucose, tolbutamide, and glucagon. Minimal C-peptide secretion could be detected in only one out of seven long term diabetics by the stimulatory tests. All seven short-term diabetics responded to at least one provocative test of beta cell reserve, although these responses were blunted. The greatest C-peptide responses occurred after glucagon administration (mean increase 0.62 pmol/ml) in short-term responders. Patients who responded to one test did not necessarily respond to another stimulus. There was no correlation between basal C-peptide levels and the ability to provoke further C-peptide secretion by any of the three tests. C-peptide responses did not correlate with % Haemoglobin A1c, mean fasting blood glucose levels, or mean blood glucose concentrations during an oral glucose tolerance test. The data indicate that stimulation tests are only useful in assessing endogenous beta cell reserve in patients with diabetes of less than 5 years duration. In diabetics of longer duration there is little insulin reserve above basal levels. Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Glucagon; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Kinetics; Male; Peptides; Tolbutamide | 1980 |
The influence of supervision and endogenous insulin secretion on the course of insulin-dependent diabetes mellitus.
In order to study the importance of out-patients' supervision on survival, a prospective study of 1061 juvenile diabetics was performed. After the first hospitalization at the Steno Memorial Hospital 5.3 +/- 4.5 years after the onset of diabetes, this population of diabetics was divided into two comparable groups by their own practitioners. One group (n = 525) was referred for further out-patient supervision to the out-patient clinic, the other group (n = 536) was not. 96.7% of the patients were followed at least 25 years. A highly significant increased survival was seen in patients seen in 4-5 times a year at the diabetic out-patient clinic. Death from ketoacidosis, hypoglycemia, and suicide was significantly higher in the group not referred for further out-patient control, and death in uremia occured earlier in this group. Juvenile diabetics with long-standing diabetes and persisting endogenous insulin secretion evaluated on the basis of C-peptide examination had significantly less severe retinopathy and nephropathy than comparable patients without endogenous insulin secretion, and survival of juvenile diabetics with clinical indications of persisting endogenous insulin secretion seems not to be different from non-diabetics. Topics: Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Male; Middle Aged; Patient Compliance; Quality of Health Care | 1980 |
Insulin biosynthesis and C-peptide. Practical applications from basic research.
Topics: Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Diagnosis, Differential; Humans; Hypoglycemia; Insulin; Islets of Langerhans; Peptides; Proinsulin | 1980 |
Urine C-peptide, beta-cell function, and insulin requirement.
Urinary C-peptide excretion was investigated as a method for monitoring beta-cell function in diabetic patients and for studying the contribution of endogenous insulin production to diabetic control. Control subjects had variations in serum and urine C-peptide immunoreactivity that correlated with basal and meal-related insulin secretion. In a group of well-controlled juvenile diabetic patients, those receiving high doses of insulin had low or negligible C-peptide excretion, whereas most patients with low exogenous insulin requirements had near-normal urinary C-peptide excretion. Patients treated for diabetic ketoacidosis had recovery of beta-cell function as measured by C-peptide immunoreactivity in serial urine specimens. Thus, measurement of urinary C-peptide excretion is a simple technique that may be useful in assessing endogenous insulin production in juvenile diabetic patients. Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male; Peptides | 1980 |
B-cell response to exercise in diabetic and non-diabetic children.
20 non-diabetic and 11 insulin dependent diabetic (IDD) children underwent short time (20 min) bicycle ergometer exercise followed by a 10 min rest period. Glucose, IRI, C-peptide and proinsulin were determined prior to and at the end of the exercise, and again after 10 min rest. While no significant change in mean glucose was observed during exercise in the non-diabetics, significant decreases were observed in IRI, C-peptide and proinsulin. After 10 min rest glucose as well as the three B-cell secretory products increased significantly. The change in glucose was significantly (p less than 0.001) correlated to the change in IRI. In the resting period IRI rose more than C-peptide in some subjects. IRI even rose without simultaneous rise in C-peptide indicating a release of tissue bound IRI. The group of IDD children did not show any significant changes in glucose and total IRI, while the endogenous insulin, as measured by C-peptide, did show a fall during exercise. The same was found for proinsulin. The lack of increased endogenous secretion during the rest period was most likely due to suppression of B-cell due to hyperinsulinism and lack of increased glucose concentrations during the rest period. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Islets of Langerhans; Male; Physical Exertion; Proinsulin | 1980 |
[The remission stage in juvenile diabetes].
Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Secretion; Remission, Spontaneous | 1980 |
Chlorpropamide-alcohol flushing is not useful for individual genetic counseling of diabetic patients.
The presence or absence of chlorpropamide-alcohol flushing (CPAF) was not correlated with the classification of diabetes. Five out of twelve patients with juvenile-onset diabetes (JOD) flushed and three out of four patients with maturity-onset diabetes in young people (MODY) did not flush. Consequently, CPAF cannot be used for individual genetic counseling in diabetes mellitus. Topics: Adolescent; Adult; Blushing; C-Peptide; Child; Chlorpropamide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Ethanol; Genetic Counseling; Humans; Middle Aged; Risk; Tolbutamide | 1980 |
[Infantile diabetes mellitus. Metabolic problems and therapeutic prospects].
Topics: Blood Coagulation Disorders; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Diabetic Ketoacidosis; Diabetic Retinopathy; Glucagon; Hemoglobin A; Humans; Insulin; Insulin Secretion | 1979 |
Insulin secretion in non-obese (J-type) diabetics in Papua New Guinea.
Nine of ten non-obese non-ketotic diabetics attending Port Moresby General Hospital had detectable C-peptide in plasma. All had received insulin for at least two months at the time of study. It is concluded that many non-obese non-ketotic young diabetics in Papua New Guinea retain pancreatic insulin secretion and so resemble the maturity onset diabetics of "Western" countries. Topics: Adolescent; Adult; Body Weight; C-Peptide; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Humans; Insulin; Insulin Secretion; Male; New Guinea | 1979 |
Free insulin, bound insulin, C-peptide and the metabolic control in juvenile onset diabetics: comparison of C-peptide secretors and non-secretors during 24 hours conventional insulin therapy.
In two groups of juvenile onset diabetics similar in age, weight, diet and daily insulin dosage (eight without C-peptide, group I; eight with C-peptide, group II) the serum levels of free and antibody bound insulin, C-peptide, glucose, lactate, alanine and FFA were determined over 24 h. In addition the affinity and binding capacity of the insulin antibodies were determined in vitro. No correlation was found between free or bound insulin and glucose. This holds true for the individual profiles as well as for the averaged profiles of the two groups. Free insulin and lactate or alanine were positively correlated in the C-peptide secreting group. C-peptide secretion followed the flucturations of the glucose level during 24 h in each individual patient. As a group, C-peptide secretors were better controlled than non-secretors with respect to mean blood glucose, M-value and the lability index and showed higher free insulin levels despite a similar daily insulin dosage. The possible reasons for this fact are discussed. No correlation was found between the affinity characteristics of the insulin antibodies and the degree of metabolic control or the daily insulin dosage. Topics: Adolescent; Adult; Alanine; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 1; Fatty Acids, Nonesterified; Female; Humans; Insulin; Insulin Antibodies; Lactates; Male; Peptides | 1979 |
Human plasma C-peptide immunoreactivity: its correlation with immunoreactive insulin in diabetes, and chronic liver and renal diseases.
The correlation between plasma C-peptide immunoreactivity (CPR) and immunoreactive insulin (IRI) was investigated during the oral glucose tolerance test in 20 normals, 127 diabetics, and 39 non-diabetics with chronic liver or renal disorders. When all subjects were included, the increment of CPR 30 minutes after glucose load (deltaCPR) correlated well with that of IRI (deltaIRI) (r = 0.66, p less than 0.001), but the return of CPR towards the basal level was delayed as compared with IRI. The positive correlation was also observed between the sum of 6 IRI and that of 6 CPR values during the glucose tolerance test in diabetics and controls (r = 0.53, p less than 0.001). deltaCPR/deltaBS (30 min.) was also well correlated with deltaIRI/deltaBS (30 min.), and was specifically low in diabetics. Insulin-treated maturity-onset diabetics showed low but considerable CPR responses while no CPR responses were observed in insulin-treated juvenile diabetics. In each plasma sample, CPR always exceeded IRI on the molar basis. At fasting CPR/IRI ratio was 15.6 +/- 1.7 (mean +/- SE) in normals and 14.9 +/- 1.3 approximately 16.9 +/- 1.0 in diabetics. In chronic liver diseases IRI response was augmented while CPR response was not different from that of controls, and the molar ratio of CPR/IRI was significantly low (9.5 +/- 1.1). On the contrary, it exceeded that of normals in chronic renal diseases (35.7 +/- 14.9). It is concluded that, first, the plasma CPR response appears to be a valuable indicator of pancreatic B-cell function, and second, it is, nevertheless, modified in chronic liver or renal disorders. Topics: Adolescent; Adult; Antigens; C-Peptide; Child; Chronic Disease; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Kidney Diseases; Liver Diseases; Male; Middle Aged; Obesity; Peptides | 1979 |
Hemoglobin A1c (HbA1c) in children with long standing and newly diagnosed diabetes mellitus.
In 35 children with long-standing diabetes mellitus, a significant correlation was found between the hemoglobin A1c (HbA1c)--and the 24-hour urinary glucose excretion. By contrast, 11 newly diagnosed diabetic children had grossly elevated HbA1c-concentrations, but no correlations could be established between the levels of HbA1c and the duration of symptoms, blood glucose, glycosuria, ketonuria and the acid--base status. However, HbA1c and C-peptide were significantly correlated. The elevated HbA1c-concentrations decreased towards normal in all of these 11 children after 2--3 months following adequate therapy. The results suggest that the determination of HbA1c may serve as a valuable metabolic control index in children with long-standing diabetes mellitus, but adds little information in newly diagnosed patients. For the individual diabetic child during the early treatment period, HbA1c may be the index of choice for adequacy of metabolic control. Topics: Acid-Base Equilibrium; Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Glycosuria; Hemoglobin A; Humans; Infant; Time Factors | 1979 |
Clinical significance of C-peptide.
Topics: C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Fasting; Humans; Immunoassay; Peptides | 1979 |
[Blood serum content of C-peptide and insulin in obese children].
Topics: Adolescent; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Insulin; Obesity; Peptides; Prediabetic State | 1979 |
beta-cell function in children with diabetes.
Although it is generally believed that insulin secretion is minimal or absent in juvenile-onset diabetes, we have found appreciable levels of C-peptide at the time of onset in 12 patients, 4 to 16 years old (9.3 +/- 4.2). Ten of them had ketonuria but none severe ketoacidosis. All entered a remission period. Most of the patients had near normal C-peptide levels during the remission, and their beta cells had the capacity to respond to a breakfast stimulation with increased insulin secretion. C-peptide and proinsulin were also determined in 98 juvenile diabetics with age at onset of 1 to 16 years (6.8 +/- 3.9) and a duration of diabetes between two and 17 years (6.7 +/- 3.4). Many were found to have persisting beta-cell function, which seems to be of importance for ensuring stability in metabolic control. Although little is known about factors that may slow or reverse the process leading to beta-cell failure, our results suggest that early detection and intensive treatment of diabetes before severe metabolic disturbances have occurred may help preserve beta-cell function. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Fasting; Humans; Infant; Insulin; Islets of Langerhans; Ketone Bodies; Kinetics | 1978 |
Prevalence of residual beta-cell function in insulin-dependent diabetics in relation to age at onset and duration of diabetes.
The influence of the age at onset as well as the duration of disease on the prevalence of residual beta-cell function was studied in insulin-dependent diabetic patients. Two hundred and sixty-seven patients presented at an early age (10-19.9 years) and 158 patients had a late onset (30-39.9 years of age). beta-cell function was evaluated by measuring serum C-peptide immunoreactivity. Fifty-six patients (21.0 per cent) in the early-onset group and 64 (40.5 per cent) in the late-onset group had residual beta-cell function. The prevalence of residual beta-cell function was almost 100 per cent during the first two years of disease and was lower thereafter in diabetics with early onset. About 15 per cent of all patients with a duration between 15 and 35 years had residual beta-cell secretory function. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Insulin; Islets of Langerhans; Radioimmunoassay | 1978 |
The effect of residual insulin secretion on exocrine pancreatic function in juvenile-onset diabetes mellitus.
Residual beta cell function was studied in 18 juvenile-onset diabetics by measuring serum C-peptide immunoreactivity (CPR) fasting, and after IV injection of glucagon (1 mg). This was compared with the exocrine pancreatic response to an IV infusion of secretin and cholecystokinin-pancreozymin. Outputs of pancreatic bicarbonate, amylase and trypsin were measured. Exocrine secretory pancreatic function was decreased in 14 patients. Fasting and maximal CPR showed that 9 patients had residual insulin secretion. For these 'CPR-secretors' there was a strong correlation between CPR and output of bicarbonate (r = 0.87, p less than 0.005) and amylase (r = 0.7, p less than 0.05), but not with trypsin. These results suggest the existence of an endocrine-exocrine relationship in the pancreas. Topics: Adolescent; Adult; Amylases; Bicarbonates; C-Peptide; Cholecystokinin; Diabetes Mellitus, Type 1; Female; Glucagon; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Pancreas; Secretin; Trypsin | 1978 |
C-peptide secretion during the remission phase of juvenile diabetes.
C-peptide secretion was studied in eight juvenile diabetics during the remission phase of the disease. The release of C-peptide was measured after a (1) normal intravenous glucose tolerance test, (2) a double glucose tolerance test, (3) an arginine infusion, and (4) after an intravenous glucose tolerance test followed by an arginine infusion. Under all conditions the intravenous glucose load had only a minimal effect on the secretion of C-peptide, while arginine alone or after the intravenous glucose tolerance test stimulated the release of the peptide in all patients. Pretreatment with glucose did not augment the effect of arginine on C-peptide release. The results indicate that during the remission phase of juvenile-onset diabetes the endocrine pancreas does not recognize glucose as and appropriate signal for C-peptide release and cannot transform the amplifying effect of glucose into a higher hormonal secretion rate. Topics: Adolescent; Adult; Arginine; Blood Glucose; C-Peptide; Child; Diabetes Mellitus, Type 1; Drug Synergism; Female; Glucose Tolerance Test; Humans; Islets of Langerhans; Male; Peptides; Remission, Spontaneous | 1978 |
Persistent insulin secretion, assessed by plasma C-peptide estimation in long-term juvenile diabetics with a low insulin requirement.
In order to investigate whether patients with long-standing juvenile diabetes mellitus (onset of diabetes before the age of 30) and a low daily insulin requirement (less than 0.50 units/kg body weight) still have functioning B-cells, plasma C-peptide was determined after stimulation (OGTT and glucagon/tolbutamide) in 64 patients with diabetes of more than 18 years' duration (mean 31 years). Measurable endogenous insulin production was found in 24% of the patients. The prevalence of severe retinopathy was lower in the secretors than in the non-secretor group. There was no difference in insulin antibody concentration between the two groups. Furthermore, the insulin requirement in the secretor group was relatively constant during the course of diabetes. Metabolic control was similar in both groups. It is concluded that a persisting but low activity of endogenous insulin production can be found in many long-term juvenile diabetics with a low insulin requirement, while others without any residual beta-cell function develop a low insulin requirement for unknown reasons. Topics: Adult; Aged; C-Peptide; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Male; Middle Aged; Peptides; Time Factors | 1978 |
Sustained insulin-induced remissions of juvenile diabetes by means of an external artificial pancreas.
Remission of diabetes was attempted in 12 recent acute onset ketosis-prone juvenile diabetes after short term (5 +/- 1 days) but excellent blood glucose control by the external artificial beta-cell. The comparison group comrised patients undergoing traditional treatment (n = 28). Nine (75%) persistent (over 3-14 months of duration) although partial (oral drugs required) remissions were obtained in the former group as compared to 3 (11%) in the latter group (p less than 0.05). Cases which showed remissions after insulin infusion had a plasma insulin response to IV glucagon still present before insulin infusion, and a daily urinary C-peptide excretion significantly enhanced after (p less than 0.01). Urinary C-peptide/blood glucose remained improved during the remission period. Thus, early effective treatment by means of the artificial pancreas may break the vicious circle hyperglycaemia-insulin depletion-hyperglycaemia and lead to frequent and sustained remissions of juvenile diabetes. Topics: Acute Disease; Adolescent; Adult; C-Peptide; Diabetes Mellitus, Type 1; Humans; Insulin; Monitoring, Physiologic; Pancreas; Remission, Spontaneous; Time Factors | 1978 |
Human proinsulin in insulin-treated juvenile diabetics.
Topics: Adolescent; Adult; C-Peptide; Child; Child, Preschool; Diabetes Mellitus; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Antibodies; Proinsulin; Radioimmunoassay | 1977 |
Quantitation of human pancreatic beta-cell function by immunoassay of C-peptide in urine.
Human proinsulin connecting peptide (C-peptide) was measured by immunoassay in urine from 25 normal subjects, 18 patients with diabetes mellitus, and 34 patients with various degrees of renal insufficiency. Assay validation studies showed that pancreatic C-peptide was quantitatively recovered when added to urine. Fractionation of urine by gel filtration indicated that most endogenous C-peptide eluted in fractions that corresponded to the C-peptide standard. In 34 nondiabetic subjects with normal kidney function or various renal diseases, C-peptide clearance was independent of creatinine clearance over a range of 6 to 190 ml./min. Urine C-peptide clearance (5.1 +/- 0.6 ml./min.) is greater than that of insulin (1.1 +/- 0.2 ml./min.), and the total quantity of C-peptide excreted in the urine per day represents 5 per cent of pancreatic secretion, as against only 0.1 per cent of secreted insulin. Healthy subjects excreted 36 +/- 4 mug. C-peptide per 24 hours, while this value in juvenile-onset diabetics was only 1.1 +/- 0.5 mug. Adult-onset diabetics excreted 24 +/- 7 mug./24 hr., the range overlapping the excretory rates of both normal subjects and juvenile-onset diabetics. Two insulin-requiring adult-onset diabetics showed significant beta-cell reserve during the course of acute infections. These results suggest that urine C-peptide provides a useful means of assessing beta-cell secretory capacity over a period of time and is especially advantageous when frequent blood sampling is not feasible. Topics: Acute Kidney Injury; C-Peptide; Chromatography, Gel; Creatinine; Diabetes Mellitus, Type 1; Humans; Immunoassay; Islets of Langerhans; Kidney; Peptides | 1977 |
C-peptide in juvenile diabetes.
C-peptide can be used as a measure of endogenous insulin secretion in insulin treated diabetics with insulin antibodies. At the onset of juvenile diabetes insulin production is thought to be absent or minimal, but we have found rather high levels of C-peptide, even in ketoacidotic patients. The ketoacidosis does not mean an irreversible beta cell failure. In the postinitial remission period with stable metabolism many patients have normal or almost normal C-peptide levels and their beta cells have the capacity to respond to natural stimulation with an increased insulin secretion. For some unknown reason the metabolism becomes more labile coinciding with decreasing C-peptide values. However, even several years beyond the postinitial remission period many juvenile diabetics have some persistent beta cell function, and it has been shown that even trace remnants of beta cell function are of importance for stabilization of the metabolism. There is no reason to believe that the beta cell failure should be predetermined e.g. by genetic factors. However, little is known how to influence the progression and stop the increasing beta cell failure. Some of our results suggest that an early detection and an intensive treatment of diabetes before severe metabolic disturbances and pronounced insulin deficiency have appeared, may increase the possibility of preserving some beta cell function. Topics: Adolescent; Blood Glucose; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Fasting; HLA Antigens; Humans; Insulin Antibodies; Islets of Langerhans; Ketones; Peptides; Physical Exertion; Proinsulin; Remission, Spontaneous | 1977 |
C-peptide in juvenile diabetics beyond the postinitial remission period. Relation to clinical manifestations at onset of diabetes, remission and diabetic control.
A group of 58 diabetics, age 6-17 years and with a duration of diabetes of 3-14 years was studied in order to show whether the nature of the clinical manifestations and the treatment at the onset of the disease are related to the subsequent C-peptide production and also whether remaining C-peptide production is related to better diabetic control. The relations between a number of clinical and laboratory variables were analysed including the degree of ketosis and the insulin dose given at onset of diabetes, the incidence of postinitial remission period, the fasting C-peptide level after the remission period, the level of insulin antibodies and the actual diabetic control expressed as the degree of glucosuria in the patients' urine tests at home. Multiple regression analysis was the main method used. Postinitial remission was positively correlated to initial insulin dose and negatively correlated to duration of ketonuria at onset. C-peptide, which was found in 24.1% of the patients was positively correlated to age at onset and initial insulin dose, but negatively correlated to ketonuria at onset. Diabetic control was positively correlated to insulin dose at onset and to C-peptide level, but negatively correlated to insulin antibodies. It could further be shown that patients who had received a more vigorous treatment immediately at onset had both a higher incidence of postinitial remission and a better diabetic control. The results suggest that an early diagnosis followed by rapid normalization of the metabolism at the onset of juvenile diabetes increase the possibility of preservation of some of the endogenous insulin production, which seems to facilitate diabetic control. Topics: Adolescent; Age Factors; C-Peptide; Child; Diabetes Mellitus, Type 1; Diabetic Ketoacidosis; Female; Glycosuria; HLA Antigens; Humans; Insulin; Insulin Antibodies; Ketone Bodies; Male; Peptides; Regression Analysis; Remission, Spontaneous; Time Factors | 1977 |
C-peptide in diabetic children after stimulation with clucagon compared with fasting C-peptide levels in non-diabetic children.
Fasting serum C-peptide and total immunoreactive insulin (IRI) were determined in 38 non-diabetic children and adolescents 6-22 years old. C-peptide varied between 0.22-0.73 pmol/ml (mean +/- SD, 0.45 +/- 0.11). There was a tendency to higher values during puberty. No difference was found between subjects with or without a family history for diabetes. IRI varied between 0-31 millimcron/m1 (mean +/- SD, 11.3 +/- 6.5). The C-peptide response to glucagon was studied in 10 insulin dependent juvenile diabetics 11-19 years old, who had had measurable amounts of fasting C-peptide on some occasions during the previous years. Duration of diabetes varied between 4-12 years. A slight but significant rise in C-peptide level occurred in 3 patients. Their metabolic control estimated on the basis of daily urinalysis was "excellent" or "good". The results support the hypothesis that even trace remnants of the beta cell function may be of importance for the metabolic control in juvenile diabetes. Topics: Adolescent; Adult; C-Peptide; Child; Diabetes Mellitus, Type 1; Fasting; Female; Glucagon; Humans; Injections, Intravenous; Insulin; Male; Peptides | 1977 |
Determination of free and total insulin and C-peptide in insulin-treated diabetics.
Serum levels of free and total insulin as well as total C-peptide immunoreactivity (C-peptide and proinsulin) and C- peptide were measured in insulin-treated diabetics with circulating insulin antibodies by the addition of polyethylene glycol (PEG) before and after acidification. PEG resulted in complete precipitation of insulin antibodies from serum and made it possible to measure free insulin in the supernatant. Incubation of serum at 37 degrees C. for two hours before addition of PEG resulted in values for free insulin that probably resembled the in-vivo levels most closely. The same method could also be used to remove proinsulin bound to circulating insulin antibodies and permitted the measurement of C-peptide in the supernatant. Clinical studies using this approach indicate that combined measurements of serum free and total insulin and C-peptide provide information that is helpful in understanding the contribution of endogenous and exogenous insulin to the course and metabolic control of insulin-requiring diabetic patients. Topics: Antibodies; C-Peptide; Centrifugation; Chemical Precipitation; Chromatography, Gel; Diabetes Mellitus; Diabetes Mellitus, Type 1; Female; Humans; Insulin; Iodine Radioisotopes; Peptides; Polyethylene Glycols; Pregnancy; Pregnancy in Diabetics; Proinsulin; Temperature | 1977 |
HLA-types, C-peptide and insulin antibodies in juvenile diabetes.
HLA-types were determined in 102 juvenile diabetics. HLA-B8 was found in 39 patients (RR 2.64; p less than 0.01) and HLA-BW15 in 32 patients (RR 1.33; n.s.). HLA-B7 was found in 14 patients (RR 0.40; p less than 0;05). There were no correlations between HLA-B8 or BW15 and family history of diabetes, occurrence of infection before onset of diabetes, ketonuria at onset or the age at onset of diabetes. Serum C-peptide, insulin binding capacity of IgG and total serum insulin, IRI, were determined in 94 patients who had had diabetes for more than two years and who were beyond the remission period. Measurable amounts of C-peptide were found in 33 patients (34.7%). There was no evidence of a relationship between any particular HLA-antigen and the B-cell function except for an increased incidence of do a decreased incidence of detectable C-peptide in patients with the combination HLA-B8, W15. Only four patients (4.3%) were lacking insulin antibodies; HLA-BW15 positive patients had higher levels of insulin antibodies than other groups, while HLA-B7 positive patients had lower levels; The results suggest that HLA-B7 and HLA-B18 might be associated with a different and perhaps milder form of juvenile diabetes. Topics: Adolescent; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Histocompatibility Antigens; HLA Antigens; Humans; Infant; Infections; Insulin; Insulin Antibodies; Ketone Bodies; Peptides | 1977 |
[C-peptide: secretion and metabolism in different functional states and with abnormal B-cell function (author's transl)].
Fasting C-peptide levels and those after tolbutamide or glucose stimulation were measured in normal subjects. In patients with various hypo- or hyper-functions of the endocrine pancreas, C-peptide levels were compared with the corresponding insulin levels. In insulin-dependent maturity-onset diabetics there were both normal and elevated serum C-peptide levels. In juvenile diabetics and patients with total duodenopancreatectomy there was no measureable C-peptide. It is concluded that the half-life of C-peptide is three times that of insulin. Topics: C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glucose; Half-Life; Humans; Insulin; Pancreatectomy; Peptides; Tolbutamide | 1977 |
[Urinalysis of school children for the screening of juvenile diabetes mellitus (for 3 consecutive years in a single area) and C-peptide secretory capacity during 50g glucose loading].
Topics: Adolescent; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Female; Glucose Tolerance Test; Humans; Male; Mass Screening; Peptides; Tokyo | 1977 |
Human C-peptide. Part II: Clinical studies.
Human C-peptide is determined by radioimmunoassay. On gel filtration of serum from a healthy subject and from a patient with islet cell carcinoma, C-peptide (MW 3025) appears ahead of insulin (MW 5808) and shows much higher molar concentrations than the hormone. Human proinsulin cross-reacts with our antiserum to synthetic human C-peptide. On direct determination of immunomeasurable C-peptide (IMCP) in fasting serum of 25 healthy subjects we find an average of 1.8 (+/- 0.4) ng/ml, corresponding to 60.4 X 10(-11) Mol/l. The molar concentration is about five-fold as compared to IMI (immuno-measurable insulin). IMCP and IMI patterns are not identical on stimulation of beta-cell secretion in healthy subjects by i.v. glucose or glucose-glibenclamide. This is probably due to differences in peripheral metabolism of both compounds. We conclude from our results that C-peptide determined in peripheral venous serum is a better indicator of beta-cell secretion than is insulin. Among 26 insulin-treated juvenile diabetics 15 show not measurable and 11 subnormal IMCP levels in fasting serum. No rise in IMCP is found 1-2 h following breakfast. Four juvenile patients receiving no insulin in a phase of total diabetes remission have normal or raised fasting IMCP concentrations. Only 2 out of 24 adult diabetics (16 treated with insulin and 8 with tablets) show non-measurable fasting IMCP concentrations, in another 4 patients values are below and in the remaining 18 cases above 1 ng/ml serum. Stimulation of beta-cell secretion through glucose-glibenclamide is more or less impaired in all adult diabetics compared to the healthy subjects. Topics: C-Peptide; Chromatography, Gel; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glucose; Glyburide; Humans; Insulin; Pancreatic Hormones; Peptides | 1976 |
Human C-peptide immunoreactivity (CPR) in blood and urine - evaluation of a radioimmunoassay method and its clinical applications.
A double-antibody radioimmunoassay method, using synthetic human connecting peptide as an immunizing antigen and standard, was evaluated for clinical assay of blood and urine samples. Normal fasting blood connecting peptide immunoreacivity (CPR) was 2.45 +/- 0.96 ng/ml, increasing promptly after a 50 g oral glucose load, but somewhat slower than insulin. Molar concentration of CPR exceeded that of insulin. CPR responses to glucose were subnormal in diabetics, very low in juvenile-type cases, and often poor in patients on insulin treatment. Fasting CPR levels were elevated in patients on corticosteroid treatment and with uraemia. A patient with insulin "auto-antibody" had high serum CPR. A considerable amount of CPR appeared in urine. Normal daily excretion of CPR was 1.52 +/- 0.55 mug/kg or 55.1 +/- 18.2 ng/mg creatinine. Urine CPR was very low in juvenile-type diabetics, and elevated in patients on corticosteroid treatment. The results confirm that blood and urine CPR are useful measures of the endocrine pancreatic function. Topics: Antigen-Antibody Reactions; Blood Glucose; C-Peptide; Diabetes Mellitus; Diabetes Mellitus, Type 1; Glucose Tolerance Test; Humans; Insulin; Peptides; Radioimmunoassay | 1976 |
C-peptide in children with juvenile diabetes. A preliminary report.
Serum C-peptide, insulin-binding IgG and total insulin (IRI) were determined in 96 juvenile diabetics aged 4-21 years, with onset of diabetes at the age of 1-16 years and with 2-17 years' duration of diabetes. Thirty-four patients (35.4%) had detectable levels of C-peptide (greater than or equal to 0.04 pmol/ml). Compared to non-diabetic adults, 19 had values below the normal range, 12 showed values within the normal range (0.18-0.63 pmol/ml) and 3 rated above normal. There was a negative correlation between the fasting C-peptide concentration and the degree of ketonuria at the onset of diabetes and a positive correlation between C-peptide levels and the incidence of post-initial remission periods. Patients without detectable C-peptide had significantly higher levels of insulin antibodies than those who had detectable levels of C-peptide. The possibility of a relationship between the intensity of the initial treatment of diabetes and the preservation of the B-cell function is discussed, as well as the possibility of insulin antibodies being a cause of B-cell exhaustion. Topics: Adolescent; Adult; Age Factors; C-Peptide; Child; Child, Preschool; Diabetes Mellitus, Type 1; Humans; Insulin; Insulin Antibodies; Ketone Bodies; Peptides; Remission, Spontaneous | 1976 |
HLA-types, C-peptide and insulin antibodies in juvenile diabetics [proceedings].
Topics: C-Peptide; Diabetes Mellitus, Type 1; Histocompatibility Antigens; HLA Antigens; Humans; Insulin Antibodies; Peptides | 1976 |