humulin-s and Obesity

Recent data suggests that (pre)diabetes onset is preceded by a period of hyperinsulinemia. Consumption of the "modern" Western diet, over-nutrition, genetic background, decreased hepatic insulin clearance, and fetal/metabolic programming may increase insulin secretion, thereby causing chronic hyperinsulinemia. Hyperinsulinemia is an important etiological factor in the development of metabolic syndrome, type 2 diabetes, cardiovascular disease, polycystic ovarian syndrome, and Alzheimer's disease. Recent data suggests that the onset of prediabetes and diabetes are preceded by a variable period of hyperinsulinemia. Emerging data suggest that chromic hyperinsulinemia is also a driving force for increased activation of the hypothalamic-adrenal-pituitary (HPA) axis in subjects with the metabolic syndrome, leading to a state of "functional hypercortisolism". This "functional hypercortisolism" by antagonizing insulin actions may prevent hypoglycemia. It also disturbs energy balance by shifting energy fluxes away from muscles toward abdominal fat stores. Synergistic effects of hyperinsulinemia and "functional hypercortisolism" promote abdominal visceral obesity and insulin resistance which are core pathophysiological components of the metabolic syndrome. It is hypothesized that hyperinsulinemia-induced increased activation of the HPA axis plays an important etiological role in the development of the metabolic syndrome and its consequences. Numerous studies have demonstrated reversibility of hyperinsulinemia with lifestyle, surgical, and pharmaceutical-based therapies. Longitudinal studies should be performed to investigate whether strategies that reduce hyperinsulinemia at an early stage are successfully in preventing increased activation of the HPA axis and the metabolic syndrome.

Topics: Cushing Syndrome; Diabetes Mellitus, Type 2; Humans; Hypothalamo-Hypophyseal System; Insulin; Insulin, Regular, Human; Metabolic Syndrome; Obesity; Pituitary-Adrenal System

As patients with diabetes continue to have greater problems with obesity, the need for more medications and higher doses of insulin has increased. Some patients are so insulin resistant that they require U-500 insulin.. All insulins carry the risk of hypoglycemia. Despite being the most potent insulin available, the methodology for describing U-500 insulin administration varies. This paper examines the properties of U-500 insulin and suggests a unified method of defining how it is administered.. A literature search for English language articles that reference U-500 insulin was performed. The 51 articles, and additional websites as applicable, were independently reviewed.. Now that U-500 insulin has a specific syringe and a pen, all patients who use this should be converted to one of these two devices. The insulin dose should be described as the number of units administered.. U-500 insulin is a potent formulation and carries the risk of hypoglycemia. A unified method of administration is now available, and the description of its use should reflect the number of units administered.

Topics: Diabetes Mellitus; Humans; Hypoglycemic Agents; Injections; Insulin Resistance; Insulin, Regular, Human; Medication Errors; Obesity; Patient Education as Topic

The rise in prevalence of obesity and diabetes has created a challenge in managing increasing numbers of patients who require high doses of insulin. This article reviews the published literature on the properties of U-500 insulin and its use in clinical practice. U-500 insulin is likely to have a longer time to peak effect and a longer duration of action than similar doses of U-100 insulin. Evidence for its use in clinical practice rests on retrospective case series, which suggests that the use of U-500 insulin either by multiple daily injections or a continuous subcutaneous insulin infusion is effective in improving glycaemic control. To prevent insulin dosing and administration errors, great care must be taken in providing staff and patient education, and in developing policies for the management of patients on U-500 insulin who are admitted to hospital.

Topics: Blood Glucose; Cost-Benefit Analysis; Diabetes Mellitus, Type 2; Dose-Response Relationship, Drug; Evidence-Based Medicine; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Injections, Subcutaneous; Insulin Infusion Systems; Insulin Resistance; Insulin, Regular, Human; Male; Obesity; Patient Education as Topic; Treatment Outcome

To compare body composition, visceral adiposity, adipocytokines, and low-grade inflammation markers in prepubertal offspring of mothers who were treated with metformin or insulin for gestational diabetes mellitus (GDM).. 172 offspring of 311 mothers randomized to receive metformin (n = 82) or insulin (n = 90) for GDMwere studied at 9 years of age (follow-up rate 55%). Measurements included anthropometrics, adipocytokines, markers of the low-grade inflammation, abdominal magnetic resonance imaging (MRI), magnetic liver spectrometry (MRS), and whole body dual-energy X-ray absorptiometry (DXA).. Serum markers of low-grade inflammation, visceral adipose tissue volume, total fat percentage, and liver fat percentage were similar between the study groups. Serum adiponectin concentration was higher in children in the metformin group compared to insulin group (median 10.37 vs 9.50 µg/ml, p = 0.016). This difference between groups was observed in boys only (median 12.13 vs 7.50 µg/ml, p < 0.001). Leptin/adiponectin-ratio was lower in boys in the metformin group than in the insulin group (median 0.30 vs 0.75; p = 0.016).. Maternal metformin treatment for GDM had no effects on adiposity, body composition, liver fat, or inflammation markers in prepubertal offspring compared to maternal insulin treatment but was associated with higher adiponectin concentration and lower leptin/adiponectin-ratio in boys.

Topics: Adipokines; Adiponectin; Adiposity; Child; Diabetes, Gestational; Female; Humans; Inflammation; Insulin; Insulin, Regular, Human; Leptin; Male; Metformin; Obesity; Pregnancy

To address the need for noninvasive alternatives to metabolic surgery or duodenal exclusion devices for the management of type 2 diabetes (T2D) and obesity by developing an orally administered therapeutic polymer, GLY-200, designed to bind to and enhance the barrier function of mucus in the gastrointestinal tract to establish duodenal exclusion noninvasively.. A Phase 1, randomized, double-blind, placebo-controlled, single- (SAD) and multiple-ascending-dose (MAD) healthy volunteer study was conducted. In the SAD arm, four cohorts received a single dose of 0.5 g up to 6.0 g GLY-200 or placebo, while in the MAD arm, four cohorts received 5 days of twice-daily or three-times-daily dosing (total daily dose 2.0 g up to 6.0 g GLY-200 or placebo). Assessments included safety and tolerability (primary) and exploratory pharmacodynamics, including serum glucose, insulin, bile acids and gut hormones.. No safety signals were observed; tolerability signals were limited to mild to moderate dose-dependent gastrointestinal events. In the MAD arm (Day 5), reductions in glucose and insulin and increases in bile acids, glucagon-like peptide-1, peptide YY and glicentin, were observed following a nonstandardized meal in subjects receiving twice-daily dosing of 2.0 g GLY-200 (N = 9) versus those receiving placebo (N = 8).. GLY-200 is safe and generally well tolerated at doses of ≤2.0 g twice daily. Pharmacodynamic results mimic the biomarker signature observed after Roux-en-Y gastric bypass and duodenal exclusion devices, indicating a pharmacological effect in the proximal small intestine. This study represents the first clinical demonstration that duodenal exclusion can be achieved with an oral drug and supports further development of GLY-200 for the treatment of obesity and/or T2D.

Topics: Bile Acids and Salts; Blood Glucose; Diabetes Mellitus, Type 2; Double-Blind Method; Glucose; Humans; Insulin; Insulin, Regular, Human; Obesity

Obesity confers paradoxical survival benefits in heart failure with preserved ejection fraction (HFpEF). The purpose of this study was to examine the impact of DM and insulin treatment status on the associations of body mass index (BMI) with the death risks in HFpEF patients.. HFpEF patients from the TOPCAT trial were included. Cox regression model was constructed to assess the relationship of BMI with the risks of all-cause death and cardiovascular death. Restricted cubic splines were used to characterize the dose-response associations of BMI with risks of death.. Compared with normal weight, hazard ratios of all-cause death in overweight and class I obesity were 0.62 (0.45-0.85), 0.67 (0.47-0.94) in no DM HFpEF patients, and 0.48 (0.25-0.91), 0.41 (0.22-0.79) in non-insulin-treated DM patients. However, insulin treatment removed this beneficial effect. Consistent results were found when modeling for time-updated BMI. Cubic spline analyses suggested a linear trend of increased death risk with higher BMI in insulin-treated DM patients.. The "obesity paradox" was present in HFpEF patients without DM or with non-insulin-treated DM but absent in those with insulin-treated DM. Insulin treatment may be a crucial confounder of the obesity paradox in HFpEF patients.. URL: https://clinicaltrials.gov. Unique identifier: NCT00094302.

Topics: Body Mass Index; Diabetes Mellitus; Heart Failure; Humans; Insulin; Insulin, Regular, Human; Obesity; Stroke Volume

Human regular U-500 (U-500R) insulin (500 units/mL) is increasingly being used clinically, yet its pharmacokinetics (PK) and pharmacodynamics (PD) have not been well studied. Therefore, we compared PK and PD of clinically relevant doses of U-500R with the same doses of human regular U-100 (U-100R) insulin (100 units/mL).. This was a single-site, randomized, double-blind, crossover euglycemic clamp study. Single subcutaneous injections of 50- and 100-unit doses of U-500R and U-100R were administered to 24 healthy obese subjects.. Both overall insulin exposure (area under the serum insulin concentration versus time curve from zero to return to baseline [AUC(0-)(t)(')]) and overall effect (total glucose infused during a clamp) were similar between formulations at both 50- and 100-unit doses (90% [CI] of ratios contained within [0.80, 1.25]). However, peak concentration and effect were significantly lower for U-500R at both doses (P < 0.05). Both formulations produced relatively long durations of action (18.3 to 21.5 h). Time-to-peak concentration and time to maximum effect were significantly longer for U-500R than U-100R at the 100-unit dose (P < 0.05). Time variables reflective of duration of action (late tR(max50), tR(last)) were prolonged for U-500R versus U-100R at both doses (P < 0.05).. Overall exposure to and action of U-500R insulin after subcutaneous injection were no different from those of U-100R insulin. For U-500R, peaks of concentration and action profiles were blunted and the effect after the peak was prolonged. These findings may help guide therapy with U-500R insulin for highly insulin-resistant patients with diabetes.

Topics: Adult; Aged; Area Under Curve; Blood Glucose; Cross-Over Studies; Double-Blind Method; Female; Glucose Clamp Technique; Humans; Hypoglycemic Agents; Insulin, Regular, Human; Male; Middle Aged; Obesity

Sleeve gastrectomy (SG) successfully recovers metabolic homeostasis in obese humans and rodents while also resulting in the normalization of insulin sensitivity and insulinemia. Reduced insulin levels have been attributed to lower insulin secretion and increased insulin clearance in individuals submitted to SG. Insulin degradation mainly occurs in the liver in a process controlled, at least in part, by the insulin-degrading enzyme (IDE). However, research has yet to explore whether liver IDE expression or activity is altered after SG surgery. In this study, C57BL/6 mice were fed a chow (CTL) or high-fat diet (HFD) for 10 weeks. Afterward, the HFD mice were randomly assigned to two groups: sham-surgical (HFD-SHAM) and SG-surgical (HFD-SG). Here, we confirmed that SG improves glucose-insulin homeostasis in obese mice. Additionally, SG reduced insulinemia by reducing insulin secretion, assessed by the analysis of plasmatic C-peptide content, and increasing insulin clearance, which was evaluated through the calculation of the plasmatic C-peptide:insulin ratio. Although no changes in hepatic IDE activity were observed, IDE expression was higher in the liver of HFD-SG compared with HFD-SHAM mice. These results indicate that SG may be helpful to counteract obesity-induced hyperinsulinemia by increasing insulin clearance, likely through enhanced liver IDE expression.

Topics: Animals; C-Peptide; Diet, High-Fat; Gastrectomy; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Insulin, Regular, Human; Mice; Mice, Inbred C57BL; Mice, Obese; Obesity; Weight Loss

Topics: Animals; Female; Humans; Infant; Inhibitor of Differentiation Protein 2; Insulin; Insulin, Regular, Human; Leptin; Male; Mice; Obesity; Placenta; Pre-Eclampsia; Pregnancy; Trophoblasts

The association between FTO rs9939609 and obesity is modified by physical activity (PA) and/or insulin sensitivity (IS). We aimed to assess whether these modifications are independent, to assess whether PA and/or IS modify the association between rs9939609 and cardiometabolic traits, and to elucidate underlying mechanisms.. Genetic association analyses comprised up to 19,585 individuals. PA was self-reported, and IS was defined based on inverted HOMA insulin resistance index. Functional analyses were performed in muscle biopsies from 140 men and in cultured muscle cells.. The BMI-increasing effect of the FTO rs9939609 A allele was attenuated by 47% with high PA (β [SE], -0.32 [0.10] kg/m2, P = 0.0013) and by 51% with high IS (-0.31 [0.09] kg/m2, P = 0.00028). Interestingly, these interactions were essentially independent (PA, -0.20 [0.09] kg/m2, P = 0.023; IS, -0.28 [0.09] kg/m2, P = 0.0011). The rs9939609 A allele was also associated with higher all-cause mortality and certain cardiometabolic outcomes (hazard ratio, 1.07-1.20, P > 0.04), and these effects tended to be weakened by greater PA and IS. Moreover, the rs9939609 A allele was associated with higher expression of FTO in skeletal muscle tissue (0.03 [0.01], P = 0.011), and in skeletal muscle cells, we identified a physical interaction between the FTO promoter and an enhancer region encompassing rs9939609.. Greater PA and IS independently reduced the effect of rs9939609 on obesity. These effects might be mediated through altered expression of FTO in skeletal muscle. Our results indicated that PA and/or other means of increasing insulin sensitivity could counteract FTO-related genetic predisposition to obesity.

Topics: Alpha-Ketoglutarate-Dependent Dioxygenase FTO; Body Mass Index; Cardiovascular Diseases; Exercise; Genetic Predisposition to Disease; Genotype; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Insulin, Regular, Human; Male; Obesity; Polymorphism, Single Nucleotide

Sex-specific differences exist in insulin secretion (ISec) and sensitivity (IS) in humans. However, current fasting indices used to estimate them, such as HOMA and QUICKI, are not sex-specific. We aimed to develop sex-specific models to improve the prediction of ISec and IS by fasting measures in adults with overweight/obesity. A post hoc analysis was conducted on baseline data of two clinical trials completed between 2010 and 2020 (37 men and 61 postmenopausal women, 45-73 years, BMI > 25 kg/m

Topics: Adult; Blood Glucose; C-Peptide; Female; Glucose; Humans; Insulin; Insulin Resistance; Insulin Secretion; Insulin, Regular, Human; Male; Obesity; Overweight

Topics: Adiposity; Animals; Diet, High-Fat; Female; Insulin; Insulin, Regular, Human; Leptin; Liver; Mice; Mice, Inbred C57BL; Mice, Obese; Non-alcoholic Fatty Liver Disease; Obesity; PPAR gamma

Inflammation-induced vascular insulin resistance is an early event in diet-induced obesity and contributes to metabolic insulin resistance. To examine whether exercise and glucagon-like peptide 1 (GLP-1) receptor agonism, alone or in combination, modulate vascular and metabolic insulin actions during obesity development, we performed a euglycemic insulin clamp in adult male rats after 2 weeks of high-fat diet feeding with either access to a running wheel (exercise), liraglutide, or both. Rats exhibited increased visceral adiposity and blunted microvascular and metabolic insulin responses. Exercise and liraglutide alone each improved muscle insulin sensitivity, but their combination fully restored insulin-mediated glucose disposal rates. The combined exercise and liraglutide intervention enhanced insulin-mediated muscle microvascular perfusion, reduced perivascular macrophage accumulation and superoxide production in the muscle, attenuated blood vessel inflammation, and improved endothelial function, along with increasing endothelial nucleus translocation of NRF2 and increasing endothelial AMPK phosphorylation. We conclude that exercise and liraglutide synergistically enhance the metabolic actions of insulin and reduce vascular oxidative stress and inflammation in the early stage of obesity development. Our data suggest that early combination use of exercise and GLP-1 receptor agonism might be an effective strategy in preventing vascular and metabolic insulin resistance and associated complications during the development of obesity.. Inflammation-induced vascular insulin resistance occurs early in diet-induced obesity and contributes to metabolic insulin resistance. We examined whether exercise and GLP-1 receptor agonism, alone or in combination, modulate vascular and metabolic insulin actions during obesity development. We found that exercise and liraglutide synergistically enhanced the metabolic actions of insulin and reduced perimicrovascular macrophage accumulation, vascular oxidative stress, and inflammation in the early stage of obesity development. Our data suggest that early combination use of exercise and a GLP-1 receptor agonist might be an effective strategy in preventing vascular and metabolic insulin resistance and associated complications during the development of obesity.

Topics: Animals; Diet, High-Fat; Glucagon-Like Peptide-1 Receptor; Inflammation; Insulin; Insulin Resistance; Insulin, Regular, Human; Liraglutide; Male; Obesity; Rats

Healthy non-obese insulin resistant (IR) individuals are at higher risk of metabolic syndrome. The metabolic signature of the increased risk was previously determined. Physical activity can lower the risk of insulin resistance, but the underlying metabolic pathways remain to be determined. In this study, the common and unique metabolic signatures of insulin sensitive (IS) and IR individuals in active and sedentary individuals were determined. Data from 305 young, aged 20-30, non-obese participants from Qatar biobank, were analyzed. The homeostatic model assessment of insulin resistance (HOMA-IR) and physical activity questionnaires were utilized to classify participants into four groups: Active Insulin Sensitive (ISA, n = 30), Active Insulin Resistant (IRA, n = 20), Sedentary Insulin Sensitive (ISS, n = 21) and Sedentary Insulin Resistant (SIR, n = 23). Differences in the levels of 1000 metabolites between insulin sensitive and insulin resistant individuals in both active and sedentary groups were compared using orthogonal partial least square discriminate analysis (OPLS-DA) and linear models. The study indicated significant differences in fatty acids between individuals with insulin sensitivity and insulin resistance who engaged in physical activity, including monohydroxy, dicarboxylate, medium and long chain, mono and polyunsaturated fatty acids. On the other hand, the sedentary group showed changes in carbohydrates, specifically glucose and pyruvate. Both groups exhibited alterations in 1-carboxyethylphenylalanine. The study revealed different metabolic signature in insulin resistant individuals depending on their physical activity status. Specifically, the active group showed changes in lipid metabolism, while the sedentary group showed alterations in glucose metabolism. These metabolic discrepancies demonstrate the beneficial impact of moderate physical activity on high risk insulin resistant healthy non-obese individuals by flipping their metabolic pathways from glucose based to fat based, ultimately leading to improved health outcomes. The results of this study carry significant implications for the prevention and treatment of metabolic syndrome in non-obese individuals.

Topics: Blood Glucose; Exercise; Glucose; Humans; Insulin; Insulin Resistance; Insulin, Regular, Human; Metabolic Syndrome; Obesity

Defining the regulators of cell metabolism and signaling is essential to design new therapeutic strategies in obesity and NAFLD/NASH. E3 ubiquitin ligases control diverse cellular functions by ubiquitination-mediated regulation of protein targets, and thus their functional aberration is associated with many diseases. The E3 ligase Ube4A has been implicated in human obesity, inflammation, and cancer. However, its in vivo function is unknown, and no animal models are available to study this novel protein.. A whole-body Ube4A knockout (UKO) mouse model was generated, and various metabolic parameters were compared in chow- and high fat diet (HFD)-fed WT and UKO mice, and in their liver, adipose tissue, and serum. Lipidomics and RNA-Seq studies were performed in the liver samples of HFD-fed WT and UKO mice. Proteomic studies were conducted to identify Ube4A's targets in metabolism. Furthermore, a mechanism by which Ube4A regulates metabolism was identified.. Although the body weight and composition of young, chow-fed WT and UKO mice are similar, the knockouts exhibit mild hyperinsulinemia and insulin resistance. HFD feeding substantially augments obesity, hyperinsulinemia, and insulin resistance in both sexes of UKO mice. HFD-fed white and brown adipose tissue depots of UKO mice have increased insulin resistance and inflammation and reduced energy metabolism. Moreover, Ube4A deletion exacerbates hepatic steatosis, inflammation, and liver injury in HFD-fed mice with increased lipid uptake and lipogenesis in hepatocytes. Acute insulin treatment resulted in impaired activation of the insulin effector protein kinase Akt in liver and adipose tissue of chow-fed UKO mice. We identified the Akt activator protein APPL1 as a Ube4A interactor. The K63-linked ubiquitination (K63-Ub) of Akt and APPL1, known to facilitate insulin-induced Akt activation, is impaired in UKO mice. Furthermore, Ube4A K63-ubiquitinates Akt in vitro.. Ube4A is a novel regulator of obesity, insulin resistance, adipose tissue dysfunction and NAFLD, and preventing its downregulation may ameliorate these diseases.

Topics: Adipose Tissue, Brown; Animals; Female; Homeostasis; Humans; Inflammation; Insulin; Insulin Resistance; Insulin, Regular, Human; Male; Mice; Non-alcoholic Fatty Liver Disease; Obesity; Proteomics; Proto-Oncogene Proteins c-akt; Ubiquitin-Protein Ligases

We investigated whether lean insulin-resistant individuals manifest increased cardiometabolic risk.. 2,341 (51.8% females) healthy 16-23-year-old subjects were categorized as lean or overweight/obese; and insulin-sensitive or insulin-resistant, and compared.. In both sexes, lean insulin-sensitive and insulin-resistant subjects displayed similar measures of obesity (e.g., males, waist-to-height ratio: lean insulin-sensitive: 0.42 ± 0.03, lean insulin-resistant: 0.43 ± 0.03, overweight/obese insulin-sensitive: 0.49 ± 0.05, overweight/obese insulin-resistant: 0.53 ± 0.06). Lean insulin-sensitive individuals were more insulin-sensitive compared with their overweight/obese peers; insulin-resistant groups presented similar insulin-sensitivity (males, the Quantitative insulin-sensitivity check index (QUICKI): lean insulin-sensitive: 0.354 ± 0.022, lean insulin-resistant: 0.304 ± 0.013, overweight/obese insulin-sensitive: 0.343 ± 0.019, overweight/obese insulin-resistant: 0.299 ± 0.015). The two-factor analysis of variance indicated an independent effect of insulin sensitivity, overweight/obesity, and their interaction on the continuous metabolic syndrome score (p < 0.001, all; males, lean insulin-sensitive: 1.87 ± 0.35, lean insulin-resistant: 2.14 ± 0.42, overweight/obese insulin-sensitive: 2.15 ± 0.40, overweight/obese insulin-resistant: 2.75 ± 0.69). C-reactive protein, leukocyte count, and glomerular filtration rate in both sexes; uric acid, asymmetric dimethyl-arginine, and soluble vascular adhesion protein-1 in males; and soluble receptor for advanced glycation end-products in females were independently associated with insulin resistance. Among phenotypes associated with low QUICKI, the distribution of insulin-resistant individuals was random.. Later clinical consequences of insulin resistance in lean subjects remain to be elucidated in longitudinal studies.

Topics: Body Mass Index; Cardiovascular Diseases; Cross-Sectional Studies; Female; Humans; Insulin; Insulin Resistance; Insulin, Regular, Human; Male; Obesity; Overweight; Receptor for Advanced Glycation End Products; Retrospective Studies; Young Adult

To examine the determinants and metabolic impact of the reduction in fasting and postload insulin levels after a low n-6 to n-3 polyunsaturated fatty acid (PUFA) ratio diet in obese youth.. Insulin secretion and clearance were assessed by measuring and modelling plasma insulin and C-peptide in 17 obese youth who underwent a nine-point, 180-minute oral glucose tolerance test (OGTT) before and after a 12-week, eucaloric low n-6:n-3 polyunsaturated fatty acid (PUFA) ratio diet. Hepatic fat content was assessed by repeated abdominal magnetic resonance imaging.. Insulin clearance at fasting and during the OGTT was significantly increased after the diet, while body weight, glucose levels, absolute and glucose-dependent insulin secretion, and model-derived variables of β-cell function were not affected. Dietary-induced changes in insulin clearance positively correlated with changes in whole-body insulin sensitivity and β-cell glucose sensitivity, but not with changes in hepatic fat. Subjects with greater increases in insulin clearance showed a worse metabolic profile at enrolment, characterized by impaired insulin clearance, β-cell glucose sensitivity, and glucose tolerance, and benefitted the most from the diet, achieving greater improvements in glucose-stimulated hyperinsulinaemia, insulin resistance, and β-cell function.. We showed that a 12-week low n-6:n-3 PUFA ratio diet improves hyperinsulinaemia by increasing fasting and postload insulin clearance in obese youth, independently of weight loss, glucose concentrations, and insulin secretion.

Topics: Adolescent; Blood Glucose; Diet; Fatty Acids, Omega-3; Glucose; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Insulin, Regular, Human; Obesity

Preclinical rodent and nonhuman primate models investigating maternal obesity have highlighted the importance of the intrauterine environment in the development of insulin resistance in offspring; however, it remains unclear if these findings can be translated to humans. To investigate possible intrauterine effects in humans, we isolated mesenchymal stem cells (MSCs) from the umbilical cord tissue of infants born to mothers of normal weight or mothers with obesity. Insulin-stimulated glycogen storage was determined in MSCs undergoing myogenesis in vitro. There was no difference in insulin action based on maternal obesity. However, maternal free fatty acid (FFA) concentration, cord leptin, and intracellular triglyceride content were positively correlated with insulin action. Furthermore, MSCs from offspring born to mothers with elevated FFAs displayed elevated activation of the mTOR signaling pathway. Taken together, these data suggest that infants born to mothers with elevated lipid availability have greater insulin action in MSCs, which may indicate upregulation of growth and lipid storage pathways during periods of maternal overnutrition.

Topics: Animals; Fatty Acids, Nonesterified; Female; Humans; Infant; Insulin; Insulin, Regular, Human; Mesenchymal Stem Cells; Obesity; Obesity, Maternal; Pregnancy

In the setting of obesity and insulin resistance, glycemia is controlled in part by β-cell compensation and subsequent hyperinsulinemia. Weight loss improves glycemia and decreases hyperinsulinemia, whereas weight cycling worsens glycemic control. The mechanisms responsible for weight cycling-induced deterioration in glucose homeostasis are poorly understood. Thus, we aimed to pinpoint the main regulatory junctions at which weight cycling alters glucose homeostasis in mice. Using in vivo and ex vivo procedures we show that despite having worsened glucose tolerance, weight-cycled mice do not manifest impaired whole-body insulin action. Instead, weight cycling reduces insulin secretory capacity in vivo during clamped hyperglycemia and ex vivo in perifused islets. Islets from weight-cycled mice have reduced expression of factors essential for β-cell function (Mafa, Pdx1, Nkx6.1, Ucn3) and lower islet insulin content, compared with those from obese mice, suggesting inadequate transcriptional and posttranscriptional response to repeated nutrient overload. Collectively, these data support a model in which pancreatic plasticity is challenged in the face of large fluctuations in body weight resulting in a mismatch between glycemia and insulin secretion in mice.

Topics: Animals; Blood Glucose; Diet; Glucose; Hyperinsulinism; Insulin; Insulin Resistance; Insulin Secretion; Insulin, Regular, Human; Islets of Langerhans; Mice; Obesity; Weight Cycling

The D3-Creatine (D3Cr) dilution method is a direct and accurate measure of skeletal muscle mass. In this study, we examined the association of D3Cr muscle mass with measures of insulin-glucose homeostasis in community dwelling postmenopausal women. Additionally, we examined association of sarcopenic obesity, defined as low D3Cr muscle mass and high percent body fat, with fasting plasma glucose, insulin, hemoglobin A1c and insulin resistance. Insulin resistance was measured by the homeostatic measure of insulin resistance (HOMA-IR). This pilot study included 74 participants (mean age = 82.3 years) from the Women's Health Initiative-Buffalo site. The D3Cr method was initiated at a clinic visit and used to measure muscle mass via remote urine sample collection. Descriptive and graphical approaches and age-adjusted linear regression models were used to analyze study data. We examined muscle mass as an absolute value (kg) and scaled to body weight (D3Cr muscle mass/kg). There was an inverse relationship between skeletal muscle mass, and impaired insulin-glucose homeostasis. Women with low muscle mass had higher levels of insulin (uIU/mL; β = -0.40; 95% CI: -0.79, -0.01), fasting plasma glucose (mg/dL; β = -0.1; 95% CI: -0.2, 0.03), HbA1c (%; β = -2.30; 95% CI: -5.7, 1.1), and calculated homeostatic model of insulin resistance, HOMA-IR, (β = -1.49; 95% CI: -2.9, -0.1). Sarcopenic obesity was common in this population of women; 41% of participants were categorized as having low muscle mass and high percent body fat. Results demonstrate that D3Cr muscle mass is independently associated with measures of insulin-glucose homeostasis, but obesity is a stronger predictor of insulin resistance than muscle mass.

Topics: Blood Glucose; Body Mass Index; Creatine; Female; Humans; Insulin; Insulin Resistance; Insulin, Regular, Human; Muscles; Obesity; Pilot Projects; Sarcopenia

Adipose insulin-resistant but normal weight phenotype has not been reported and hence was characterized in young Japanese women.. Body composition, a broad range of cardiometabolic health and dietary intake were cross-sectionally measured in 166 normal weight young Japanese women. They were grouped into tertile of adipose tissue-insulin resistance (AT-IR) index (fasting insulin×free fatty acids) and analyzed by analysis of variance and then Bonferroni's multiple comparison procedure.. Body mass index averaged <21 kg/m. Adipose insulin-resistant but normal weight phenotype may be associated with increased sympathetic nervous system and low-grade systemic inflammation in addition to glucose and lipid dysmetabolism through mechanisms unrelated to adiposity in young Japanese women.

Topics: Adiposity; Blood Glucose; C-Reactive Protein; East Asian People; Fasting; Female; Heart Rate; Humans; Insulin; Insulin Resistance; Insulin, Regular, Human; Obesity; Triglycerides

To determine the extent to which the presence of acanthosis nigricans confers additional risk for insulin resistance, in addition to obesity alone (body mass index, BMI) within a young, overweight, UK population.. Retrospective data were collected to compare the degree of insulin resistance within a sample of 94 young people with acanthosis nigricans, and a matched cohort of 94 participants with obesity alone. Insulin resistance was assessed by fasting glucose, fasting insulin and Homeostatic Model Assessment of insulin resistance (HOMA-IR) score (a mathematical model derived to measure insulin resistance).. The acanthotic and control group were well matched for age, BMI, BMI SDS and sex, although the groups were not matched for ethnicity. The acanthotic group showed a significantly greater median fasting insulin (215 pmol/L), mean fasting glucose (4.7 mmol/L) and median HOMA-IR score (6.4), compared with the control group (126 pmol/L, 4.5 mmol/L and 3.7, respectively). The presence of acanthosis nigricans as an indicator of insulin resistance was found to have a positive predictive value of 81% (within this study population).. Individuals with both acanthosis nigricans and obesity had significantly greater degrees of insulin resistance than individuals with obesity alone. The findings support the potential for acanthosis nigricans as a visible marker of type 2 diabetes in young people.

Topics: Acanthosis Nigricans; Case-Control Studies; Diabetes Mellitus, Type 2; Glucose; Humans; Insulin; Insulin Resistance; Insulin, Regular, Human; Obesity; Overweight; Retrospective Studies; United Kingdom

Obesity and its associated disorders constitute a growing epidemic across the world. Numerous studies have demonstrated the presence of systemic oxidative stress in patients with obesity. In this study, we show the effects of oxidative stress present in the blood from obese patients on recombinant human insulin. Insulin was incubated with whole blood (WB) from overweight subjects (OW), obese 1 patients (O1), or normal weight volunteers (NW) (n=16 for each group). Whole blood from OW and O1, unlike WB from NW, increased the carbonyl content of insulin; however, only whole blood from O1 patients increased the amount of formazan present in the hormone. Interestingly, the incubation of insulin with WB from O1 provoked a decrease in the hypoglycemic activity of the hormone (18%), an effect due to insulin polymerization. In addition, we showed that the formation of the insulin polymer generated the formation of new epitopes and the development of a new immunogenicity. These observations show that oxidative stress present in the WB of O1 patients can result in abolition of the biological activity of insulin and contribute to the development of an immune response to the hormone.

Topics: Adult; Animals; Antigen-Antibody Reactions; Biomarkers; Body Mass Index; Female; Formazans; Humans; Hypoglycemic Agents; Insulin Resistance; Insulin, Regular, Human; Mice; Obesity; Overweight; Oxidation-Reduction; Oxidative Stress; Polymerization; Protein Carbonylation; Recombinant Proteins; Young Adult