Search

Aim: To assess oxytocin's acute glucoregulatory impact in men with type 2 diabetes in the context of our previous findings that oxytocin improves β‐cell responsivity in healthy men. Methods: In a double‐blind, crossover comparison, intranasal oxytocin (24 IU) and placebo, respectively, were administered to 25 fasted men with non‐insulin–treated type 2 diabetes (age ± standard error of the mean, 63.40 ± 1.36 years; body mass index, 27.77 ± 0.66 kg/m2; HbA1c, 6.86% ± 0.08%; Homeostatic Model Assessment of Insulin Resistance (HOMA‐IR, 3.44 ± 0.39) 60 minutes before an oral glucose tolerance test (oGTT). Key outcomes were compared with previous results in men with normal weight or obesity. Results: Oxytocin compared with placebo increased plasma oxytocin concentrations and reduced the heart rate, but did not alter glucose metabolism in the 3 hours after oGTT onset (area under the curve, glucose, 2240 ± 80.5 vs. 2190 ± 69.5 mmol/L × min; insulin, 45 663 ± 4538 vs. 44 343 ± 4269 pmol/L × min; C‐peptide, 235 ± 5.1 vs. 231 ± 15.9 nmol/L × min). Conclusions: This outcome contrasts with the oxytocin‐induced attenuation of early postprandial glucose excursions in normal‐weight individuals, but is in line with the absence of respective effects in men with obesity. We conclude that insulin resistance in type 2 diabetes is associated with decreased sensitivity to the acute glucoregulatory effect of oxytocin in male individuals. [ABSTRACT FROM AUTHOR]

Objective: Dysregulated body fat distribution is a major determinant of various diseases. In particular, increased visceral fat mass and ectopic lipids in the liver are linked to metabolic disorders such as insulin resistance and type 2 diabetes. Furthermore, interscapular fat is considered to be a metabolically active fat compartment. Methods: This study measured interscapular fat mass and investigated its relationship with glucose metabolism in 822 individuals with a wide range of BMI values and different glucose tolerance statuses. Magnetic resonance imaging was used to quantify body fat depots, and an oral glucose tolerance test was performed to determine glucose metabolism. Results: Elevated interscapular fat mass was positively associated with age, BMI, and total body, visceral, and subcutaneous adipose tissue mass. High interscapular fat mass associated with elevated fasting glucose levels, glucose levels at 2 hours during the oral glucose tolerance test, glycated hemoglobin, and insulin resistance, independent of sex, age, and total body and visceral fat mass. Conclusions: In conclusion, interscapular fat might be a highly specific fat compartment with a potential impact on glucose metabolism and the pathogenesis of diabetes mellitus. [ABSTRACT FROM AUTHOR]

We performed the largest randomized, placebo‐controlled clinical trial to date (N = 112, 12‐week intervention) to investigate the effects and safety of resveratrol supplementation on liver fat content and cardiometabolic risk parameters in overweight and obese and insulin‐resistant subjects. At baseline the variability in liver fat content was very large, ranging from 0.09% to 37.55% (median, 7.12%; interquartile range, 3.85%‐12.94%). Mean (SD) liver fat content was 9.22 (6.85) % in the placebo group and 9.91 (7.76) % in the resveratrol group. During the study liver fat content decreased in the placebo group (−0.7%) but not in the resveratrol group (−0.03%) (differences between groups: P = .018 for the intention‐to‐treat [ITT] population; N = 54, resveratrol, N = 54, placebo and P = .0077 for the per protocol [PP] population). No effects of resveratrol supplementation on cardiometabolic risk parameters were observed. Resveratrol supplementation was well tolerated and safe. In conclusion, these data suggest that resveratrol supplementation is safe and that it does not considerably impact liver fat content or cardiometabolic risk parameters in humans. [ABSTRACT FROM AUTHOR]

Objective: Genome-wide association studies (GWAS) have identified single-nucleotide polymorphisms (SNPs) associated with estimates of body fat distribution. Using predefined risk allele scores, the correlation of these scores with precisely quantified body fat distribution assessed by magnetic resonance (MR) imaging techniques and with metabolic traits was investigated.Methods: Data from 4,944 MR scans from 915 subjects of European ancestry were analyzed. Body fat distribution was determined by MR imaging and liver fat content by 1 H-MR spectroscopy. All subjects underwent a five-point 75-g oral glucose tolerance test. A total of 65 SNPs with reported genome-wide significant associations regarding estimates of body fat distribution were genotyped. Four genetic risk scores were created by summation of risk alleles.Results: A higher allelic load of waist-to-hip ratio SNPs was associated with lower insulin sensitivity, higher postchallenge glucose levels, and more visceral and less subcutaneous fat mass.Conclusions: GWAS-derived polymorphisms estimating body fat distribution are associated with distinct patterns of body fat distribution exactly measured by MR. Only the risk score associated with the waist-to-hip ratio in GWAS showed an unhealthy pattern of metabolism and body fat distribution. This score might be useful for predicting diseases associated with genetically determined, unhealthy obesity. [ABSTRACT FROM AUTHOR]