Insulin Resistance In Subjects Research Articles

Human intestinal lipid storage through sequential meals reveals faster dinner appearance is associated with hyperlipidemia.

BackgroundIt is increasingly recognized that intestinal cells can store lipids after a meal, yet the effect of this phenomenon on lipid absorption patterns in insulin resistance remains unknown.MethodsThe kinetics of meal fat appearance were measured in insulin-sensitive (IS, n = 8) and insulin-resistant (IR, n = 8) subjects after sequential, isotopically labeled lunch and dinner meals. Plasma dynamics on triacylglycerol-rich (TAG-rich) lipoproteins and plasma hormones were analyzed using a nonlinear, non–steady state kinetic model.ResultsAt the onset of dinner, IS subjects showed an abrupt plasma appearance of lunch lipid consistent with the “second-meal effect,” followed by slower appearance of dinner fat in plasma, resulting in reduced accumulation of dinner TAG of 48% compared with lunch. By contrast, IR subjects exhibited faster meal TAG appearance rates after both lunch and dinner. This effect of lower enterocyte storage between meals was associated with greater nocturnal and next-morning hyperlipidemia. The biochemical data and the kinetic analysis of second-meal effect dynamics are consistent with rapid secretion of stored TAG bypassing lipolysis and resynthesis. In addition, the data are consistent with a role for the diurnal pattern of plasma leptin in regulating the processing of dietary lipid.ConclusionThese data support the concept that intestinal lipid storage may be physiologically beneficial in IS subjects.Trial registrationClinicalTrials.gov NCT02020343.FundingThis study was supported by a grant from the American Diabetes Association (grant 1-13-TS-12).

Insulin Resistance and Type 2 Diabetes in Asymptomatic Obstructive Sleep Apnea: Results of the PROOF Cohort Study After 7 Years of Follow-Up.

The aim of the study was to assess potential associations between obstructive sleep apnea (OSA) and the occurrence of diabetes mellitus and insulin resistance in the elderly. Nondiabetic volunteers (n = 549) with undiagnosed or untreated asymptomatic OSA (66.2+/−1 years at the inclusion) were evaluated as an ancillary study of the PROOF cohort study (n = 1,011). After 7 years follow-up, 494 subjects underwent assessment of fasting insulin and glucose levels. OSA was defined by an apnea-hypopnea index (AHI) of ≥15/h using polygraphy. Diabetes mellitus was defined by a fasting glucose ≥ 1.26 g/L and/or when requiring pharmacological treatment, while insulin resistance corresponded to HOMA-IR ≥ 2. Asymptomatic OSA subjects (men or women) did not display increased risk of incident diabetes (2.8 vs. 3.9%, p = 0.51). However, there was a greater frequency of insulin resistance in subjects with severe OSA (AHI > 30) [OR 2.21; 95% CI (1.22–4.02); p = 0.009]. Furthermore, multiple logistic regression showed that triglycerides levels [OR 1.61; 95% CI (1.10–2.36); p = 0.01] and fasting glycaemia [OR 4.69; 95% CI (1.12–192.78); p = 0.04], but not AHI or oxyhemoglobin desaturation index were independently associated with higher rate of insulin resistance. The deleterious metabolic effect of asymptomatic OSA in the population may be indirectly mediated via perturbations in lipids, and is particularly likely to become manifest in severe apneic subjects with higher glycemic levels.

Circulating Bile Acid Profiles: A Need for Further Examination.

Bile acids (BAs) are increasingly recognized as metabolic and chronobiologic integrators that synchronize the systemic metabolic response to nutrient availability. Alterations in the concentration and/or composition of circulating BAs are associated with a number of metabolic disorders, such as obesity, type 2 diabetes mellitus (T2DM), insulin resistance (IR), and metabolic associated fatty liver disease (MAFLD). This review summarizes recent evidence that links abnormal circulating BA profiles to multiple metabolic disorders, and discusses the possible mechanisms underlying the connections to determine the role of BA profiling as a novel biomarker for these abnormalities. The review is based on a collection of primary and review literature gathered from a PubMed search of BAs, T2DM, IR, and MAFLD, among other keywords. Obese and IR subjects appear to have elevated fasting circulating BAs but lower postprandial increase when compared with controls. The possible underlying mechanisms are disruption in the synchronization between the feeding/fasting cycle and the properties of BA-regulated metabolic pathways. Whether BA alterations are associated per se with MAFLD remains inconclusive. However, increased fasting circulating BAs level was associated with higher risk of advanced fibrosis stage. Thus, for patients with MAFLD, dynamically monitoring the circulating BA profiles may be a promising tool for the stratification of MAFLD. Alterations in the concentration, composition, and rhythm of circulating BAs are associated with adverse events in systemic metabolism. Subsequent investigations regarding these aspects of circulating BA kinetics may help predict future metabolic disorders and guide therapeutic interventions.

Single-Point Insulin Sensitivity Estimator (SPISE) as a Feasible Marker of Insulin Resistance in Adult Metabolic Syndrome: Evaluated in a Hospital Based Cross-Sectional Pilot Study at Tertiary Care Centre of Uttarakhand.

Insulin resistance (IR) plays an important role as a major determinant of Metabolic syndrome (MetS). Various methods are available for measuring insulin resistance but they are laborious, time-consuming, and costly. Therefore various surrogate markers and indices have been devised to simplify and improve the determination of insulin resistance. Recently, a new index, single point insulin sensitivity estimator (SPISE) was proposed in the European population and was found comparable to the gold standard test (hyperinsulinemic euglycemic glucose clamp).This study was planned to evaluate whether SPISE could be a useful potential low-cost indicator for predicting MetS with IR patients in Indian population. Eighty-three participants from outpatient careof AIIMS Rishikesh were evaluated after informed consent. They were divided into Metabolic syndrome (n = 56) and Non Metabolic Syndrome(n = 27), using South Asian Modified National Cholesterol Education Program- ATP-III criteria for metabolic syndrome. SPISE index, HOMA-IR, Insulin Resistance Index, Triglycerides to high-density lipoproteins cholesterol ratio (TG/HDL-C) were calculated for all the subjects. Receiver operating characteristic (ROC) curve was plotted to assess discriminatory ability of SPISE, HOMA-IR, TG/HDL-C ratio, IRI and hs-CRP to differentiate between IR(Metabolic syndrome) and non-IR (Non-Metabolic syndrome) subjects. SPISE has greater area under curve with better sensitivity and specificity compared to HOMA-IR, IRI, TG/HDL-C ratio and hs CRP. So, SPISE has better predictive ability than HOMA-IR, IRI, TG/HDL-C ratio and hs CRP to discriminate IR from non-IR cases. SPISE could be a useful potential low-cost indicator with high sensitivity and specificity for predicting IR in MetS patients.

Daily intake of yogurt drink fortified either with vitamin D alone or in combination with added calcium causes a thyroid-independent increase of resting metabolic rate in adults with type 2 diabetes: a randomized, double-blind, clinical trial.

We investigated the effect of daily intake of yogurt drink fortified with either vitamin D alone or with added calcium on resting metabolic rate (RMR), thyroid hormones and homeostatic model assessment for insulin resistance in subjects with type 2 diabetes (T2D). A total of 75 adult subjects with T2D were randomly assigned to 1 of the 3 groups to receive either D-fortified yogurt drink (DY; 1000IU vitaminD/day), Ca-D-fortified yogurt drink (CDY; 1000IU vitamin D plus 500mg calcium), or plain yogurt drink for 12 weeks. All assessments were done at the baseline and after the intervention. The concentrations of anti-thyroid peroxidase antibody (anti-TPO-Ab), intact parathyroid hormone (iPTH) and thyroid stimulating hormone (TSH) had declined significantly compared with baseline values only in the CDY group. The mean RMR increased in both DY and CDY groups (p< 0.001 for both). Also, changes of serum concentrations of 25-hydroxycalciferol (B= 2.96, 95% confidence interval (CI)= 1.3 to 4.6, p= 0.001) and iPTH (B= -2.41, 95%CI= -4.5 to -0.31, p= 0.025) remained significant predictors of RMR changes even after adjustment for changes of serum concentrations of TSH (B= -18.2, 95% CI= -61.7 to 25.2, p= 0.406). Daily intake of vitamin D together with calcium at physiological doses has attenuating effect on anti-TPO-Ab and TSH. Also, vitamin D with or without added calcium causes a significant thyroid-independent increase in RMR in euthyroid subjects with T2D. Registered at clinicaltrials.gov as NCT01229891. Novelty: Daily intake of vitamin D with calcium at physiological doses has attenuating effect on anti-TPO-Ab and TSH. Vitamin D with or without added calcium causes a thyroid-independent increase in RMR in euthyroid subjects with T2D.

1222-P: Adipose Tissue Antilipolytic Insulin Sensitivity Protects against Whole-Body Insulin Resistance and Lowers Acylcarnitine Accumulation in Adults with Obesity

The aims of this study were; 1) to assess clinical and subclinical factors associated with insulin-stimulated glucose uptake and 2) compare skeletal muscle lipid profile (untargeted lipidomics) in a sub-cohort of insulin sensitive vs. insulin resistant subjects. 66 obese adults (F=46 [BMI=34±3kg/m2], M=20 [BMI=33±2.9 kg/m2]) with homogeneous body composition completed a 2h hyperinsulinemic-euglycemic clamp, and stable isotope dilution methods to assess glucose rate of disappearance (Glucose Rd: index of insulin sensitivity), fatty acid rate of appearance (FA Ra), and hepatic glucose production (Glucose Ra) under basal and hyperinsulinemic conditions. We also performed an array of metabolic measurements (e.g., hepatic and visceral fat accumulation [via MRI], fat oxidation, lipid profile, circulating cytokines). Covariate analysis (LASSO) identified insulin-mediated suppression of FA Ra, basal glucose Ra, and fat oxidation as the cluster of measurements best predicting Glucose Rd (r=0.76, p&amp;lt;0.01). Insulin-mediated suppression of FA Ra was also the strongest independent predictor of Glucose Rd (r=0.51; p&amp;lt;0.01). As a result of greater adipose tissue anti-lipolytic response to insulin, lower FA delivery to skeletal muscle may improve insulin-mediated glucose uptake via lower muscle lipid accumulation. Importantly, we found the accumulation of several long-chain acylcarnitine species (measure of incomplete β-oxidation: C18:0,18:1,20:1,20:3) to be lower (p&amp;lt;0.05) in muscle samples from an insulin sensitive sub-cohort (Glucose Rd &amp;gt; 8.5 µmol/(min•FFM•[Insulin]); n=10) compared with an insulin resistant sub-cohort (&amp;lt; 7.2 µmol/(min•FFM•[Insulin]); n=8). In conclusion, our findings indicate that greater adipose tissue anti-lipolytic response to insulin is an important predictor of insulin-mediated glucose uptake - and acylcarnitine accumulation in skeletal muscle may mediate this effect. Disclosure M. W. Schleh: None. B. J. Ryan: None. C. Ahn: None. A. Ludzki: None. P. Varshney: None. J. B. Gillen: None. J. F. Horowitz: None. Funding National Institutes of Health (R01DK077966, P30DK089503, T32DK007245, F32DK117522); Canadian Institutes of Health Research (DFS146190, 338735)

Metabolite Profile of Treatment-Naive Metabolic Syndrome Subjects in Relation to Cardiovascular Disease Risk.

Metabolic syndrome (MetSyn) is an important risk factor for type 2 diabetes and cardiovascular diseases (CVD). This study aimed to find distinct plasma metabolite profiles between insulin-resistant and non-insulin resistant subjects with MetSyn and evaluate if MetSyn metabolite profiles are related to CVD risk and lipid fluxes. In a cross-sectional study, untargeted metabolomics of treatment-naive males with MetSyn (n = 132) were analyzed together with clinical parameters. In a subset of MetSyn participants, CVD risk was calculated using the Framingham score (n = 111), and lipolysis (n = 39) was measured by a two-step hyperinsulinemic euglycemic clamp using [1,1,2,3,3-2H5] glycerol to calculate lipolysis suppression rates. Peripheral insulin resistance was related to fatty acid metabolism and glycerolphosphorylcholine. Interestingly, although insulin resistance is considered to be a risk factor for CVD, we observed that there was little correspondence between metabolites associated with insulin resistance and metabolites associated with CVD risk. The latter mainly belonged to the androgenic steroid, fatty acid, phosphatidylethanolamine, and phophatidylcholine pathways. These data provide new insights into metabolic changes in mild MetSyn pathophysiology and MetSyn CVD risk related to lipid metabolism. Prospective studies may focus on the pathophysiological role of the here-identified biomarkers.

Visceral Adipose Tissue Phospholipid Signature of Insulin Sensitivity and Obesity.

Alterations in visceral adipose tissue (VAT) are closely linked to cardiometabolic abnormalities. The aim of this work is to define a metabolic signature in VAT of insulin resistance (IR) dependent on, and independent of, obesity. An untargeted UPLC-Q-Exactive metabolomic approach was carried out on the VAT of obese insulin-sensitive (IS) and insulin-resistant subjects (N = 11 and N = 25, respectively) and nonobese IS and IR subjects (N = 25 and N = 10, respectively). The VAT metabolome in obesity was defined among other things by changes in the metabolism of lipids, nucleotides, carbohydrates, and amino acids, whereas when combined with high IR, it affected the metabolism of 18 carbon fatty acyl-containing phospholipid species. A multimetabolite model created by glycerophosphatidylinositol (18:0); glycerophosphatidylethanolamine (18:2); glycerophosphatidylserine (18:0); and glycerophosphatidylcholine (18:0/18:1), (18:2/18:2), and (18:2/18:3) exhibited a highly predictive performance to identify the metabotype of “insulin-sensitive obesity” among obese individuals [area under the curve (AUC) 96.7% (91.9–100)] and within the entire study population [AUC 87.6% (79.0–96.2)]. We demonstrated that IR has a unique and shared metabolic signature dependent on, and independent of, obesity. For it to be used in clinical practice, these findings need to be validated in a more accessible sample, such as blood.

\u03c9-3PUFA supplementation ameliorates adipose tissue inflammation and insulin-stimulated glucose disposal in subjects with obesity: a potential role for apolipoprotein E

BackgroundLong chain omega-3 polyunsaturated fatty acids (ω-3PUFA) supplementation in animal models of diet-induced obesity has consistently shown to improve insulin sensitivity. The same is not always reported in human studies with insulin resistant (IR) subjects with obesity.ObjectiveWe studied whether high-dose ω-3PUFA supplementation for 3 months improves insulin sensitivity and adipose tissue (AT) inflammation in IR subjects with obesity.MethodsThirteen subjects (BMI = 39.3 ± 1.6 kg/m2) underwent 80 mU/m2·min euglycemic-hyperinsulinemic clamp with subcutaneous (Sc) AT biopsy before and after 3 months of ω-3PUFA (DHA and EPA, 4 g/daily) supplementation. Cytoadipokine plasma profiles were assessed before and after ω-3PUFA. AT-specific inflammatory gene expression was evaluated on Sc fat biopsies. Microarray analysis was performed on the fat biopsies collected during the program.ResultsPalmitic and stearic acid plasma levels were significantly reduced (P < 0.05) after ω-3PUFA. Gene expression of pro-inflammatory markers and adipokines were improved after ω-3PUFA (P < 0.05). Systemic inflammation was decreased after ω-3PUFA, as shown by cytokine assessment (P < 0.05). These changes were associated with a 25% increase in insulin-stimulated glucose disposal (4.7 ± 0.6 mg/kg ffm•min vs. 5.9 ± 0.9 mg/kg ffm•min) despite no change in body weight. Microarray analysis identified 53 probe sets significantly altered post- ω-3PUFA, with Apolipoprotein E (APOE) being one of the most upregulated genes.ConclusionHigh dose of long chain ω-3PUFA supplementation modulates significant changes in plasma fatty acid profile, AT, and systemic inflammation. These findings are associated with significant improvement of insulin-stimulated glucose disposal. Unbiased microarray analysis of Sc fat biopsy identified APOE as among the most differentially regulated gene after ω-3PUFA supplementation. We speculate that ω-3PUFA increases macrophage-derived APOE mRNA levels with anti-inflammatory properties.

Pioglitazone does not synergize with mirabegron to increase beige fat or further improve glucose metabolism.

BACKGROUNDBeige and brown adipose tissue (BAT) are associated with improved metabolic homeostasis. We recently reported that the β3-adrenergic receptor agonist mirabegron induced beige adipose tissue in obese insulin-resistant subjects, and this was accompanied by improved glucose metabolism. Here we evaluated pioglitazone treatment with a combination pioglitazone and mirabegron treatment and compared these with previously published data evaluating mirabegron treatment alone. Both drugs were used at FDA-approved dosages.METHODSWe measured BAT by PET CT scans, measured beige adipose tissue by immunohistochemistry, and comprehensively characterized glucose and lipid homeostasis and insulin sensitivity by euglycemic clamp and oral glucose tolerance tests. Subcutaneous white adipose tissue, muscle fiber type composition and capillary density, lipotoxicity, and systemic inflammation were evaluated by immunohistochemistry, gene expression profiling, mass spectroscopy, and ELISAs.RESULTSTreatment with pioglitazone or the combination of pioglitazone and mirabegron increased beige adipose tissue protein marker expression and improved insulin sensitivity and glucose homeostasis, but neither treatment induced BAT in these obese subjects. When the magnitude of the responses to the treatments was evaluated, mirabegron was found to be the most effective at inducing beige adipose tissue. Although monotherapy with either mirabegron or pioglitazone induced adipose beiging, combination treatment resulted in less beiging than either alone. The 3 treatments also had different effects on muscle fiber type switching and capillary density.CONCLUSIONThe addition of pioglitazone to mirabegron treatment does not enhance beiging or increase BAT in obese insulin-resistant research participants.TRIAL REGISTRATIONClinicalTrials.gov NCT02919176.FUNDINGNIH DK112282 and P20GM103527 and Clinical and Translational Science Awards grant UL1TR001998.

Gut Microbiota of Chinese Obese Children and Adolescents With and Without Insulin Resistance.

ObjectiveThe intestinal flora of gut microbiota in obese Chinese children and adolescents with and without insulin resistance (IR) was analyzed, as well as associations between the gut microbiota and two serum cytokines related to glucose metabolism, adropin and angiopoietin-like 4 (ANGPTL4).MethodsClinical data, fecal bacterial composition, glucose-related hormones, and serum adipokines (adropin and ANGPTL4) were analyzed in 65 Chinese children with exogenous obesity. The composition of the gut microbiota was determined by 16S rRNA-based metagenomics and IR was calculated using the homeostasis model assessment (HOMA).ResultsThe 65 obese subjects were divided into two groups: insulin sensitive (IS) (n=40, 57.5% males) or IR (n=25, 60% males). Principal coordinates analysis revealed that the gut microbiota samples from the IS group clustered together and separated partly from the IR group (p=0.008). By Mann-Whitney U-test, at a phylum level, a reduction of Firmicutes and an increase of Bacteroidetes in the IR subjects was observed. LEfSe analysis revealed that IS subject, when compared to their IR counterparts, harbored members of the order Coriobacteriales, Turicibacterales, Pasteurellales and family Turicibacteraceae, that were significantly more abundant. In contrast, the IR subjects had members of family Peptococcaceae that were significantly more prevalent than the IS subjects (all p<0.05). Spearman’s correlation analysis revealed that serum ANGPTL4 was positively associated with genus Bacteroides, Butyricimonas, and Alistipes, and adropin was positively associated with genus Anaerostipes and Alistipes, and negatively associated with genus Blautia (all p<0.05).ConclusionIn obese children, the gut microbiome in IR subjects was significantly discordant from the IS subjects, and the abundance of some metabolism-related bacteria correlated with the serum concentrations of adropin and ANGPTL4. These observations infer that the gut microbiota may be involved in the regulation of glucose metabolism in obesity.

Surgical site peptidylarginine deaminase 4 (PAD4), a biomarker of NETosis, correlates with insulin resistance in total joint arthroplasty patients: A preliminary report.

While obesity and insulin resistance are known risk factors for wound complications after total joint arthroplasty (TJA), the biologic causes remain to be elucidated. Recently, neutrophil extracellular trap formation (NETosis) was identified as a mediator of delayed wound healing in insulin resistant states. Herein, we explored the relationship between obesity, insulin resistance and biomarkers of NET formation in TJA subjects. We enrolled 14 obese (body mass index [BMI]≥30 kg/m2), and 15 lean (BMI<30 kg/m2) subjects undergoing primary knee or hip TJA. On the day of surgery, skeletal muscle proximal to the operated joint and plasma were collected. Protein abundance of NETosis biomarkers, peptidylarginine deaminase 4 (PAD4) and neutrophil elastase (NE) were assessed in skeletal muscle by immunoblotting and metabolic parameters (glucose, insulin, triglycerides, free fatty acids) and cell-free double-stranded DNA (cf-dsDNA) were assessed in plasma and were correlated with obesity and insulin resistance (as measured by the homeostatic model assessment for insulin resistance). When comparing lean and obese subjects, there were no significant differences in plasma cf-dsDNA or skeletal muscle NE or PAD4 abundance. In contrast, skeletal muscle PAD4 abundance, but not NE or plasma cf-dsDNA, was positively correlated with insulin resistance. Compared to insulin sensitive subjects, insulin resistant TJA subjects have higher expression of PAD4 at the surgical site and therefore may have higher rates of NET formation, which may lead to delayed surgical site wound healing.

Hepatic Insulin Resistance Is Not Pathway Selective in Humans With Nonalcoholic Fatty Liver Disease.

Both glucose and triglyceride production are increased in type 2 diabetes and nonalcoholic fatty liver disease (NAFLD). For decades, the leading hypothesis to explain these paradoxical observations has been selective hepatic insulin resistance wherein insulin drives de novo lipogenesis (DNL) while failing to suppress glucose production. Here, we aimed to test this hypothesis in humans. We recruited obese subjects who met criteria for bariatric surgery with (n = 16) or without (n = 15) NAFLD and assessed 1) insulin-mediated regulation of hepatic and peripheral glucose metabolism using hyperinsulinemic-euglycemic clamps with [6,6-2H2]glucose, 2) fasting and carbohydrate-driven hepatic DNL using deuterated water (2H2O), and 3) hepatocellular insulin signaling in liver biopsy samples collected during bariatric surgery. Compared with subjects without NAFLD, those with NAFLD demonstrated impaired insulin-mediated suppression of glucose production and attenuated-not increased-glucose-stimulated/high-insulin lipogenesis. Fructose-stimulated/low-insulin lipogenesis was intact. Hepatocellular insulin signaling, assessed for the first time in humans, exhibited a proximal block in insulin-resistant subjects: Signaling was attenuated from the level of the insulin receptor through both glucose and lipogenesis pathways. The carbohydrate-regulated lipogenic transcription factor ChREBP was increased in subjects with NAFLD. Acute increases in lipogenesis in humans with NAFLD are not explained by altered molecular regulation of lipogenesis through a paradoxical increase in lipogenic insulin action; rather, increases in lipogenic substrate availability may be the key.

Effect of the intake of high and normal protein diets with different sources of dietary protein on insulin resistance in subjects with obesity: a randomized controlled clinical trial

Effect of the intake of high and normal protein diets with different sources of dietary protein on insulin resistance in subjects with obesity: a randomized controlled clinical trial

Trends in Serum Insulin, C-Peptide and IR Levels in Non-Diabetic Young Adults – A Case Control Study

Background: Insulin resistance (IR), Body Mass Index (BMI), Waist Circumference (WC), Waist to Hip ratio (WHR) at risk levels have been identified as major predisposary factors for the development of Metabolic Syndrome (MS). Objectives: To compare the trends in serum insulin, C-peptide and IR levels in non-diabetic obese and non-obese young adults (20-40 years). Methods: The study was designed as a case control study and was conducted to compare serum parameters and selected anthropometric parameters in obese subjects (n=50) and non-obese subjects (n=50). After obtaining written consent, 100 non – diabetic (fasting blood sugar &lt; 100 mg/ dL) aged between 20-40 years were recruited for the study. The study was conducted at the clinic of Family Medicine, University of Sri Jayewardenepura after obtaining ethical clearance from ethics review committee of University of Sri Jayewardenepura. According to BMI subjects were categorized as obese (BMI ≥ 25 kgm-2) and non-obese (BMI ≤ 25 kgm-2). WC, Hip Circumferences were measured and WHR was calculated. Fasting serum glucose (Glucose oxidase kit), serum insulin and serum C-peptide (ELISA method) levels were measured and IR was calculated according to HOMA-IR equation. Results: Among the parameters assessed; anthropometric parameters WC (p= 0.000) and WHR (P= 0.03) and biochemical parameters IR (P=0.003), fasting serum insulin (P = 0.006), glucose (P = 0.022) and C peptide (P=0.012) showed a significant difference in the obese group when compared to non-obese group. Higher number of hyperinsulinaemic (40%) and IR (38%) subjects were in the obese category compared to non-obese category (Hyperinsulinaemia: 6% and IR: 8%). Conclusions: In healthy non-diabetics, the obese group had significantly higher WC, WHR, IR, serum insulin and C-peptide levels indicating the risk of developing non-communicable diseases. In addition to the known risk factor (WC, WHR, Insulin, and IR) significant elevation of c-peptide in obese individuals might have the potential of being a promising screening tool in obese subjects.

Effect of the intake of dietary protein on insulin resistance in subjects with obesity: a randomized controlled clinical trial.

We compared the effect of diets with different amounts and sources of dietary protein on insulin sensitivity (IS) in subjects with obesity and insulin resistance (IR). Eighty subjects with obesity (BMI ≥ 30kg/m2) and IR (Matsuda index < 4.3 and HOMA-IR ≥ 2.5) over 18years old were randomized to four groups for a one-month period: a normal protein diet (< 20%) with a predominance of animal protein (Animal NP) or vegetable protein (Vegetable NP) and a high-protein diet (25-30%) with a predominance of animal protein (Animal HP) or vegetable protein (Vegetable HP). Baseline and final measurements of body weight, body composition, biochemical parameters, blood pressure (BP), resting energy expenditure and plasma amino acid profiles were performed. Body weight, BMI and waist circumference decreased in all groups. Interestingly, the IS improved more in the Animal HP (Matsuda index; 1.39 vs 2.58, P = 0.003) and in the Vegetable HP groups (Matsuda index; 1.44 vs 3.14, P < 0.0001) after one month. The fat mass, triglyceride levels, C-reactive protein levels and the leptin/adiponectin index decreased; while, the skeletal muscle mass increased in the Animal and Vegetable HP groups. The BP decreased in all groups except the Animal NP group. Our study demonstrates that a high-protein hypocaloric diets improves IS by 60-90% after one month in subjects with obesity and IR, regardless of weight loss and the source of protein, either animal or vegetable. The trial is registered at clinicaltrials.gov (NCT03627104), August 13, 2018.

Efficacy and Cardiovascular Safety of Thiazolidinediones.

Type 2 diabetes mellitus (T2DM) is characterized by a progressive beta cell dysfunction in the setting of peripheral insulin resistance. Insulin resistance in subjects with type 2 diabetes and metabolic syndrome is primarily caused by an ectopic fat accumulation in the liver and skeletal muscle. Insulin sensitizers are particularly important in the management of T2DM. Though thiazolidinediones (TZDs) are principally insulin sensitizers, they possess an ability to preserve pancreatic β-cell function and thereby exhibit durable glycemic control. Cardiovascular outcome trials (CVOTs) have shown that Glucagon-like-peptide 1 receptor agonists (GLP-1 RAs) and sodium glucose transporter-2 inhibitors (SGLT2i) have proven cardiovascular safety. In this era of CVOTs, drugs with proven cardiovascular (CV) safety are often preferred in patients with preexisting cardiovascular disease or at risk of cardiovascular disease. In this review, we will describe the three available drugs belonging to the TZD family, with special emphasis on their efficacy and CV safety.

Metabolic impact of weight loss induced reduction of adipose ACE-2 – Potential implication in COVID-19 infections?

Background & aimsAngiotensin converting enzyme (ACE)-2 is a modulator of adipose tissue metabolism. However, human data of adipose ACE-2 is rarely available. Considering that, ACE-2 is believed to be the receptor responsible for cell entry of SARS-CoV-2, a better understanding of its regulation is desirable. We therefore characterized the modulation of subcutaneous adipose ACE-2 mRNA expression during weight loss and the impact of ACE-2 expression on weight loss induced short- and long-term improvements of glucose metabolism. Methods143 subjects (age > 18; BMI ≥ 27 kg/m2) were analyzed before and after a standardized 12-week dietary weight reduction program. Afterwards subjects were randomized to a 12-month lifestyle intervention or a control group (Maintain-Adults trial). Insulin sensitivity (IS) was estimated by HOMA-IR (as an estimate of liver IS) and ISIClamp (as an estimate of skeletal muscle IS). ACE-2 mRNA expression (ACE-2AT) was measured in subcutaneous adipose tissue before and after weight loss. ResultsACE-2AT was not affected by obesity, but was reduced in insulin resistant subjects. Weight loss resulted in a decline of ACE-2AT (29.0 (20.0–47.9) vs. 21.0 (13.0–31.0); p = 1.6 ∗ 10−7). A smaller reduction of ACE-2 AT (ΔACE-2AT) was associated with a larger improvement of ISIClamp (p = 0.013) during weight reduction over 3 months, but not with the extend of weight loss. The degree of changes in insulin resistance were preserved until month 12 and was also predicted by the weight loss induced degree of ΔACE-2AT (p = 0.011). ConclusionsOur data indicate that subcutaneous adipose ACE-2 expression correlates with insulin sensitivity. Weight loss induced decline of subcutaneous adipose ACE-2 expression might affect short- and long-term improvement of myocellular insulin sensitivity, which might be also relevant in the context of ACE-2 downregulation by SARS-CoV-2.Trial registration: ClinicalTrials.gov number: NCT00850629, https://clinicaltrials.gov/ct2/show/NCT00850629, date of registration: February 25, 2009.

The transcontinental variability of nonalcoholic fatty liver disease.

To compare the phenotype of lean versus overweight (OW) and obese (OB) subjects with non-alcoholic fatty liver disease (NAFLD) across multiple continents. A retrospective study of histologically defined subjects from a single center each in France (Fr), Brazil (Br), India (In) and United States (US) was performed. A total of 70 lean [body mass index (BMI) < 25 kg/m2] subjects (Fr:Br:In:US: 16:19:22:13) with NAFLD were compared to 136 OW (BMI > 25 kg/m2, BMI < 29 kg/m2) (n = 28:33:52:23) and 224 OB subjects (BMI > 29 kg/m2) (n = 81:11:22:103). Lean French subjects had the lowest incidence of type 2 diabetes while those from Brazil (P < 0.01) had the highest. Lean subjects had similar low-density lipoprotein-cholesterol, but higher high-density lipoprotein-cholesterol compared to obese subjects in all regions. In both lean and obese subjects, there were both insulin-sensitive and insulin-resistant subjects. Lean French subjects were most insulin-sensitive while those from Brazil were mostly insulin-resistant. For each weight category, subjects from India were more insulin-sensitive than those from other regions. Disease activity increased from lean to overweight to obese in France but was similar across weight categories in other regions. The phenotype of NAFLD in lean subjects varies by region. Some obese subjects with NAFLD are insulin-sensitive. We hypothesize that genetics and region-specific disease modifiers account for these differences.

Serum glypican4 and glycosylphosphatidylinositol-specific phospholipase D levels are associated with adipose tissue insulin resistance in obese subjects with different glucose metabolism status.

Glypican4 (GPC4) is a novel adipokine associated with obesity and insulin resistance. GPC4 was cleaved by the glycosylphosphatidylinositol-specific phospholipase D (GPLD1) in an anchored site of the glycosylphosphatidylinositol, and then was released into the extracellular environment. Herein, we investigated the changes of serum GPC4 and GPLD1 levels in obese subjects with different glucose metabolism status and their relationship with adipose tissue insulin resistance index (Adipo-IR) in Chinese north populations. A total of 221 obese subjects and 37 normal controls (NC) were recruited in this study. Obese subjects were divided into normal insulin (NI) group, hyperinsulinemia (HI) group, impaired glucose tolerance (IGT) group, and type 2 diabetes mellitus (DM) group. Serum GPC4, GPLD1, and adiponectin were determined by commercially available ELISA kits. Serum GPC4 levels in the HI, IGT, and DM groups were significantly higher than those in the NC and NI groups (2.27 ± 0.58ng/mL, 2.21 ± 0.60ng/mL, 2.49 ± 0.67ng/mL vs. 1.70 ± 0.33ng/mL, 1.93 ± 0.34ng/mL, P < 0.05). GPC4 was positively correlated with GPLD1, which was the most important influencing factor of GPC4. Adipo-IR was independently and positively associated with serum GPC4 and GPLD1. For GPC4, afteradjustmentforconfounders, the risk of adipose tissue insulin resistance in subjects with the highest tertile was 2.974-fold that of those with the lowest tertile (OR = 2.974, P = 0.013). For GPLD1, before adjustment for lipids, the increased probability still existed (Model 2, OR = 3.568, P = 0.003). GPC4 is an adipokine associated with adipose tissue insulin resistance, and its activitymay beregulatedby GPLD1. GPC4 may be a marker for adipose tissue insulin resistance in Chinese north obese populations.