c-peptide and Kidney-Diseases

C-peptide has intrinsic biological activity and may be renoprotective. We conducted a systematic review to determine whether C-peptide had a beneficial effect on renal outcomes. MEDLINE, EMBASE, and the Cochrane Central Databases were searched for human and animal studies in which C-peptide was administered and renal endpoints were subsequently measured. We identified 4 human trials involving 74 patients as well as 18 animal studies involving 35 separate experiments with a total of 641 animals. In humans, the renal effects of exogenously delivered C-peptide were only studied in type 1 diabetics with either normal renal function or incipient nephropathy. Pooled analysis showed no difference in GFR (mean difference, -1.36 mL/min/1.73 m2, p = 0.72) in patients receiving C-peptide compared to a control group, but two studies reported a reduction in glomerular hyperfiltration (p<0.05). Reduction in albuminuria was also reported in the C-peptide group (p<0.05). In diabetic rodent models, C-peptide led to a reduction in GFR (mean difference, -0.62 mL/min, p<0.00001) reflecting a partial reduction in glomerular hyperfiltration. C-peptide also reduced proteinuria (mean difference, -186.25 mg/day, p = 0.05), glomerular volume (p<0.00001), and mesangial matrix area (p<0.00001) in diabetic animals without affecting blood pressure or plasma glucose. Most studies were relatively short-term in duration, ranging from 1 hour to 3 months. Human studies of sufficient sample size and duration are needed to determine if the beneficial effects of C-peptide seen in animal models translate into improved long-term clinical outcomes for patients with chronic kidney disease. (PROSPERO CRD42014007472).

Topics: Acute Kidney Injury; Animals; C-Peptide; Diabetes Mellitus, Experimental; Glomerular Filtration Rate; Humans; Kidney Diseases; Treatment Outcome

Kidney disease remains a major cause of morbidity and mortality in Canada and worldwide. New medical treatments are needed to reduce the progression of kidney disease to improve patient outcomes. C-peptide is normally released by pancreatic beta-cells along with insulin in healthy individuals, and has been shown to have intrinsic biological activity and to potentially be renoprotective. The effect of exogenous C-peptide on kidney structure and function, and the role of C-peptide in the treatment of kidney disease have not yet been fully elucidated.. We will conduct a systematic review of the literature in human clinical trials and mammalian experimental models to ascertain the current evidence for the role of C-peptide as a potential therapeutic agent for the treatment of kidney disease. We aim to identify whether exogenously delivered C-peptide has an effect on clinically relevant outcomes such as glomerular filtration rate, proteinuria, kidney histology, requirement of renal replacement therapy, and mortality. We will search MEDLINE, EMBASE, and the Cochrane Central Databases for human or animal studies in which C-peptide was administered and renal endpoints were subsequently measured. Study quality will be assessed using the Cochrane Collaboration's tool for assessing risk of bias. If appropriate, a meta-analysis will be performed as per standard techniques.. The results of this study will determine the potential role of C-peptide as a therapeutic intervention for patients with kidney disease and will help guide subsequent clinical trials. The study may also provide insight into which patients or disease states are likely to benefit the most from C-peptide.. PROSPERO CRD42014007472.

Topics: C-Peptide; Glomerular Filtration Rate; Humans; Kidney; Kidney Diseases; Proteinuria; Systematic Reviews as Topic; Treatment Outcome

Topics: Biomarkers; C-Peptide; Chromatography, Gel; Diabetes Mellitus, Type 2; Diagnostic Techniques, Endocrine; Factitious Disorders; Humans; Hypoglycemia; Immunoassay; Insulin Resistance; Insulin-Secreting Cells; Insulinoma; Kidney Diseases; Pancreatic Function Tests; Pancreatic Neoplasms; Proinsulin; Reference Values; Specimen Handling

Topics: Adult; Aged; Biomarkers; C-Peptide; Diabetes Complications; Diabetes Mellitus; Drug Administration Schedule; Female; Humans; Infections; Insulin; Kidney Diseases; Liver Diseases; Male; Middle Aged; Patient Selection; Pregnancy

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

Previous studies had showed divergent findings on the associations of C-peptide and/or uric acid (UA) with renal dysfunction odds in patients with type 2 diabetes mellitus (T2DM). We hypothesized that there were non-linear relationships between C-peptide, UA and renal dysfunction odds. This study aimed to further investigate the relationships of different stratification of C-peptide and UA with renal dysfunction in patients with T2DM.. We conducted a cross-sectional real-world observational study of 411 patients with T2DM. The levels of fasting C-peptide, 2h postprandial C-peptide, the ratio of fasting C-peptide to 2h postprandial C-peptide (C0/C2 ratio), UA and other characteristics were recorded. Restricted cubic spline (RCS) curves was performed to evaluated the associations of stratified C-peptide and UA with renal dysfunction odds.. Fasting C-peptide, C0/C2 ratio and UA were independently and significantly associated with renal dysfunction in patients with T2DM as assessed by multivariate analyses (p < 0.05). In especial, non-linear relationships with threshold effects were observed among fasting C-peptide, UA and renal dysfunction according to RCS analyses. Compared with patients with 0.28 ≤ fasting C-peptide ≤ 0.56 nmol/L, patients with fasting C-peptide < 0.28 nmol/L (OR = 1.38, p = 0.246) or fasting C-peptide > 0.56 nmol/L (OR = 1.85, p = 0.021) had relatively higher renal dysfunction odds after adjusting for confounding factors. Similarly, compared with patients with 276 ≤ UA ≤ 409 μmol/L, patients with UA < 276 μmol/L (OR = 1.32, p = 0.262) or UA > 409 μmol/L (OR = 6.24, p < 0.001) had relatively higher odds of renal dysfunction.. The renal dysfunction odds in patients with T2DM was non-linearly associated with the levels of serum fasting C-peptide and UA. Fasting C-peptide and UA might have the potential role in odds stratification of renal dysfunction.

Topics: C-Peptide; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Fasting; Humans; Kidney Diseases; Uric Acid

Our previous cross-sectional study has demonstrated the independently non-linear relationship between fasting C-peptide with renal dysfunction odds in patients with type 2 diabetes (T2D) in China. This longitudinal observational study aims to explore the role of serum C-peptide in risk prediction of new-onset renal dysfunction, then construct a predictive model based on serum C-peptide and other clinical parameters.. The patients with T2D and normal renal function at baseline were recruited in this study. The LASSO algorithm was performed to filter potential predictors from the baseline variables. Logistic regression (LR) was performed to construct the predictive model for new-onset renal dysfunction risk. Power analysis was performed to assess the statistical power of the model.. During a 2-year follow-up period, 21.08% (35/166) of subjects with T2D and normal renal function at baseline progressed to renal dysfunction. Six predictors were determined using LASSO regression, including baseline albumin-to-creatinine ratio, glycated hemoglobin, hypertension, retinol-binding protein-to-creatinine ratio, quartiles of fasting C-peptide, and quartiles of fasting C-peptide to 2h postprandial C-peptide ratio. These 6 predictors were incorporated to develop model for renal dysfunction risk prediction using LR. Finally, the LR model achieved a high efficiency, with an AUC of 0.83 (0.76 - 0.91), an accuracy of 75.80%, a sensitivity of 88.60%, and a specificity of 70.80%. According to the power analysis, the statistical power of the LR model was found to be 0.81, which was at a relatively high level. Finally, a nomogram was developed to make the model more available for individualized prediction in clinical practice.. Our results indicated that the baseline level of serum C-peptide had the potential role in the risk prediction of new-onset renal dysfunction. The LR model demonstrated high efficiency and had the potential to guide individualized risk assessments for renal dysfunction in clinical practice.

Topics: C-Peptide; Creatinine; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Humans; Kidney Diseases

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

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

Accurate dosing of medications for glycemic control is a challenge for clinicians in diabetic patients with kidney disease. Diminishing glomerular filtration rates are associated with decreased renal clearance of insulin and increased prevalence of hypoglycemic episodes. Measurement of glucose/C peptide ratios may be useful to guide dosing in those patients who receive powerful insulin secretogogues as glomerular function decreases with age and disease.. In order to determine the relationship between glucose, C-peptide and renal function, we reviewed the records of patients with type 2 diabetes followed in our kidney hypertension clinic who met the following criteria: age 35-90 years, requirement of medications to control glycemia, at least 4 simultaneous measurements of C peptide, HbA1c, creatinine and blood glucose.. 87 patients (67 males, 20 females), ages 67.1 ± 10.6 years, BMI 32.5 ± 5.2, A1c 8.2 ± 1.2%, eGFR 73 ± 27.2 ml/min, had glucose/C-peptide ratios 60.7 ± 46.4. 59% of the total group were taking insulin secretogogues. Patients were divided into groups based upon mean eGFR and use or absence of insulin secretogogues. Glucose C-peptide ratios were lowest in the quartile of patients with the lowest eGFR (<50 ml/min).. Diminished renal function and advanced age are associated with the lowest glucose/C-peptide ratios, independent of achieved glycemic control. With similar use of secretogogues, glucose/C-peptide ratio were lower when eGFR was ≤49 ml/min compared to >50-80 ml/min. Use of secretogogues was associated with decreased glucose/C-peptide levels. In patients with reduced renal function (eGFR < 50 ml/min), use of insulin secretogogues may be associated with lower glucose/C-peptide ratios associated with higher risks for hypoglycemic reactions.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 2; Female; Glomerular Filtration Rate; Humans; Kidney Diseases; Male; Middle Aged; Prognosis

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

Inflammatory mechanisms may play an important role in the pathogenesis of cisplatin nephrotoxicity. Agonists of the peroxisome proliferator-activated receptor-gamma (PPARgamma), such as rosiglitazone, have been recently demonstrated to regulate inflammation by modulating the production of inflammatory mediators and adhesion molecules. The purpose of this study was to examine the protective effects of rosiglitazone on cisplatin nephrotoxicity and to explore the mechanism of its renoprotection.. Mice were treated with cisplatin with or without pre-treatment with rosiglitazone. Renal functions, histological findings, aquaporin 2 (AQP2) and adhesion molecule expression, macrophage infiltration and tumour necrosis factor-alpha (TNF-alpha) levels were investigated. The effect of rosiglitazone on nuclear factor (NF)-kappaB activity and on viability was examined using cultured human kidney (HK-2) cells.. Rosiglitazone significantly decreased both the damage to renal function and histological pathology after cisplatin injection. Pre-treatment with rosiglitazone reduced the systemic levels of TNF-alpha and down-regulated adhesion molecule expression in addition to the infiltration of inflammatory cells after cisplatin administration. Rosiglitazone restored the decreased AQP2 expression after cisplatin treatment. Pre-treatment with rosiglitazone blocked the phosphorylation of the p65 subunit of NF-kappaB in cultured HK-2 cells. Rosiglitazone had a protective effect via a PPARgamma-dependent pathway in cisplatin-treated HK-2 cells.. These results showed that pre-treatment with rosiglitazone attenuates cisplatin-induced renal damage through the suppression of TNF-alpha overproduction and NF-kappaB activation.

Topics: Anilides; Animals; Apoptosis; C-Peptide; Cell Line; Chromans; Cisplatin; Drug Evaluation, Preclinical; Glioma; Humans; Hypoglycemic Agents; Inflammation; Insulin; Intercellular Adhesion Molecule-1; Kidney; Kidney Diseases; Kidney Function Tests; Kidney Tubules, Proximal; Macrophages; Male; Mice; Mice, Inbred C57BL; Monocytes; PPAR gamma; Prostaglandin D2; Protein Transport; Rosiglitazone; Thiazolidinediones; Transcription Factor RelA; Troglitazone; Tumor Necrosis Factor-alpha

This study examined the relationship of fasting serum glucose, insulin, C-peptide, glycosylated hemoglobin A (HbA1c), and Homeostasis Model Assessment (HOMA)-insulin resistance to risk of chronic kidney disease (CKD) among 6453 persons without diabetes (fasting glucose <126 mg/dl and not taking diabetes medication) who participated in the Third National Health and Nutrition Examination Survey and were aged 20 yr or older. CKD was defined as an estimated GFR <60 ml/min per 1.73 m(2). The prevalence of CKD was significantly and progressively higher with increasing levels of serum insulin, C-peptide, HbA1c, and HOMA-insulin resistance. After adjustment for potential confounding variables, the odds ratio of CKD for the highest compared with the lowest quartile was 4.03 (95% confidence interval [CI], 1.81 to 8.95; P = 0.001), 11.4 (95% CI, 4.07 to 32.1; P < 0.001), 2.67 (95% CI, 1.31 to 5.46; P = 0.002), and 2.65 (95% CI, 1.25 to 5.62; P = 0.008) for serum insulin, C-peptide, HbA1c levels, and HOMA-insulin resistance, respectively. For a one SD higher level of serum insulin (7.14 micro U/ml), C-peptide (0.45 Deltamol/ml), HbA1c (0.52%), and HOMA-insulin resistance (1.93), the odds ratio (95% CI) of CKD was 1.35 (1.16 to 1.57), 2.78 (2.25 to 3.42), 1.69 (1.28 to 2.23), and 1.30 (1.13 to 1.50), respectively. These findings combined with knowledge from previous studies suggest that the insulin resistance and concomitant hyperinsulinemia are presented in CKD patients without clinical diabetes. Further studies into the causality between insulin resistance and CKD are warranted.

Topics: Blood Glucose; C-Peptide; Chronic Disease; Female; Glycated Hemoglobin; Homeostasis; Humans; Insulin; Insulin Resistance; Kidney Diseases; Male; Middle Aged; Nutrition Surveys; Risk Factors; United States

Topics: C-Peptide; Contraindications; Humans; Hypoglycemic Agents; Kidney Diseases; Metformin

To assess renal functional outcome at 10-21 years in 16 consecutive patients with rheumatic disease, treated with alkylating agents for secondary renal AA-amyloidosis, and to review management principles developed during 21 years.. Renal function was assessed by S-creatinine and the albumin/creatinine clearance ratio, and arthritic activity by joint score and C-reactive protein (CRP). In the event of signs of renal deterioration, cyclophosphamide, or since 1975 chlorambucil, was given until stable remission of the arthritis was obtained.. Of the 7 cases of precipitous uremia that occurred, 4 were not treated with cytostatics at the patients' local hospitals. By 1992, median survival of renal function was 11 years (range 4-21). At 10 years 12 (75%) still had kidneys with preserved function, and at that stage accounted for 22 instances of renal deterioration treated with alkylating agents for periods of 6-45 months (median 13). Renal function was improved in 18 of these instances, and deterioration arrested in 3, the general trend being stabilized or moderately increased S-creatinine and successively declining proteinuria. Prompt institution of corticosteroid treatment is regarded as indispensable at increase of CRP/S-AA due to infection or surgery.. Our results indicate that the survival of renal function may be substantially prolonged (compared to no treatment) when cyclophosphamide, or preferably chlorambucil, is appropriately administered at signs of kidney deterioration due to active arthritis, and lifelong, continuous monitoring maintained.

Topics: Albumins; Amyloidosis; Antineoplastic Agents; C-Peptide; Chlorambucil; Creatinine; Cyclophosphamide; Female; Follow-Up Studies; Humans; Kidney; Kidney Diseases; Male; Middle Aged; Rheumatic Diseases; Serum Amyloid A Protein; Time Factors

The variation of urinary C-peptide clearance in relation to hyperglycemia and renal damage was evaluated in 57 patients with non-insulin-dependent diabetes mellitus (NIDDM) with and without overt proteinuria, 14 nondiabetic patients with renal disease (RD) and 18 healthy control subjects. Urinary C-peptide clearance expressed as the ratio of urinary C-peptide to creatinine clearance (CCP/CCR) in the fasting state did not differ in control subjects and RD patients, and was higher equally in NIDDM patients with and without proteinuria. In NIDDM patients without overt proteinuria, urinary levels of C-peptide, beta 2-microglobulin (B2M), N-acetyl-beta-D-glucosaminidase (NAG) and albumin as well as CCP/CCR ratio all decreased significantly with short-term glycemic control (P less than 0.05). Despite a wide range of CCP/CCR ratio (0.07-0.73), a weak but significant correlation (r = 0.56, P less than 0.005) was found between fasting serum and urinary C-peptide levels in NIDDM patients. These results suggest that urinary C-peptide may easily be affected by hyperglycemia per se rather than renal damage, while urinary B2M, NAG and albumin may be affected by both hyperglycemia and renal damage. When the urinary C-peptide level is interpreted, the influence of hyperglycemia on it must be taken into consideration.

Topics: Acetylglucosaminidase; beta 2-Microglobulin; Biomarkers; C-Peptide; Creatinine; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Humans; Hyperglycemia; Kidney Diseases; Male; Middle Aged; Proteinuria; Reference Values

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

Topics: Adult; Blood Glucose; C-Peptide; Chronic Disease; Female; Glucagon; Humans; Kidney; Kidney Diseases; Kinetics; Male; Middle Aged; Pancreatic Hormones

A scheme is advanced whereby plasma-lipoproteins form an integrated controlled pathway for storage of energy as triglyceride. The importance of insulin within this system is indicated and the consequence of possible errors considered. Changes secondary to organ disease are found to fit within the proposed pathway. Although many refinements remain to be added, this hypothesis seems to form a plausible framework within which lipoprotein abnormality and the underlying condition may be better understood and thereby treated.

Topics: Apolipoproteins; C-Peptide; Cholesterol; Chylomicrons; Diabetes Mellitus; Energy Metabolism; Humans; Hypolipoproteinemias; Insulin; Kidney Diseases; Lecithin Cholesterol Acyltransferase Deficiency; Lipoprotein Lipase; Lipoproteins; Lipoproteins, VLDL; Phosphatidylcholine-Sterol O-Acyltransferase; Triglycerides