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Type 2 diabetes (T2D) risk is lower in females than males. It has been reported that females have greater pancreatic 훽‐cell function than males, which may at least in part contribute to the T2D risk in females. 훽‐cell function is influenced by exercise training; however, previous trials comparing 훽‐cell function between the sexes have not included participants matched for training status. Furthermore, the acute effects of different modes of exercise on 훽‐cell function, and whether sex inherently influences these effects, are largely unexamined. Males and females (12/sex) completed a 120‐min oral glucose tolerance test (OGTT) at rest (CON) and following acute bouts of high‐intensity interval exercise (HIIE), moderate intensity continuous (MIC) exercise, and low‐load high‐repetition (LLHR) resistance exercise to assess whether sex inherently influences baseline and/or post‐exercise pancreatic function in the absence of pathology. We found no sex differences in basal pancreatic 훽‐cell function. Females had greater basal insulin clearance following MIC exercise compared to males (p = 0.01) and males tended to have a higher potentiation ratio following HIIE (p = 0.07). Females also had lower glucose sensitivity following MIC exercise compared to HIIE (p = 0.007) and LLHR (p = 0.003). Insulin clearance during the OGTT was greater following HIIE as compared with CON and MIC exercise (p = 0.02). 2‐H oral glucose insulin sensitivity was greater following LLHR compared to CON (p = 0.01). Acute bouts of different modes of exercise do not differentially influence 훽‐cell function but do influence insulin clearance and insulin sensitivity. Therefore, sex and exercise mode interact to differentially influence insulin clearance and glucose sensitivity. [ABSTRACT FROM AUTHOR]

AIMS: One‐hour post‐load hyperglycaemia has been proposed as an independent predictor of type 2 diabetes in adults. We examined whether 1‐hour plasma glucose (1hPG) during an oral glucose tolerance test (OGTT) can predict changes in the glucose tolerance status of a multi‐ethnic cohort of youths with normal glucose tolerance (NGT). Materials and methods: A total of 202 obese youths with NGT (33.7% Caucasian, 31.1% Hispanic, 32.2% African American) underwent a 3‐hour OGTT at baseline and after a 2‐year follow‐up period. Whole‐body insulin sensitivity, insulin secretion, β‐cell function and insulin clearance were estimated by modeling plasma glucose, insulin and C‐peptide levels. Results: Obese youths with 1hPG ≥7.4 mmol/L (or 133 mg/dL; n = 83) exhibited higher body mass index (BMI), plasma triglycerides and fasting and post‐load glucose concentrations than individuals with 1hPG <7.4 mmol/L. Also, 1hPG ≥7.4 mmol/L was associated with a lower disposition index (DI) (P < 0.0001) and with alterations in whole‐body insulin sensitivity, β‐cell function and insulin clearance. Adolescents with 1hPG ≥7.4 mmol/L were approximately three times more likely to develop prediabetes (ie, impaired glucose tolerance and/or impaired fasting glucose) over time (OR, 2.92 [1.22‐6.98]; P = 0.02), independent of age, sex, race/ethnicity, BMI, insulin sensitivity, DI and plasma glucose concentrations. No differences emerged in the risk of prediabetes related to 1‐hour hyperglycaemia among different ethnic groups. Conclusions: A plasma glucose concentration ≥ 7.4 mmol/L at 1 hour during an OGTT is associated with a worse clinical and metabolic phenotype and may be an independent predictor of progression to prediabetes in obese youths with NGT. [ABSTRACT FROM AUTHOR]

Excess insulin secretion and hyperinsulinaemia contribute to the progression of type 2 diabetes. However, the mechanisms leading to insulin hypersecretion remain largely unknown. Based on our preliminary data, we examined whether triglycerides and very low‐density lipoprotein (VLDL) are independently associated with insulin secretion, and whether ethnicity/race modulates these associations. Fasting triglycerides and VLDL were measured in a multiethnic cohort of 630 non‐diabetic adolescents. Insulin secretion, β‐cell function parameters, insulin sensitivity and insulin clearance were estimated through a 3‐h oral glucose tolerance test. Metabolic assessments were repeated after 2 years in 239 subjects. Triglycerides and triglyceride‐rich VLDL (large and medium size fractions) were associated with both basal and glucose‐stimulated insulin secretion, after adjustment for age, sex, ethnicity, BMI z‐score, plasma glucose, and insulin sensitivity. Ethnicity per se had an impact on lipid profile and β‐cell function, but did not modulate the effect of triglycerides/VLDL on insulin secretion. At follow‐up, changes in triglyceride levels were proportional to changes in insulin secretion. These findings support the hypothesis that hypertriglyceridaemia is an important stimulus for β‐cell insulin release in young people under both fasting and fed conditions. [ABSTRACT FROM AUTHOR]

Aim: Multiple studies support the efficacy of combining a glucagon‐like peptide 1 receptor agonist (GLP‐1RA) with basal insulin in people with type 2 diabetes inadequately controlled on dual/triple oral therapy. Fixed‐ratio combinations of basal insulin + GLP‐1RA represent a further advance to facilitate management. We assessed the impact of fixed‐ratio combination basal insulin + GLP‐1RA treatment on β‐cell function. Materials and Methods: We analysed data from 351 participants in the LixiLan‐G trial (NCT02787551) randomized to receive iGlarLixi (insulin glargine 100 U/ml + lixisenatide) or to continue daily/weekly GLP‐1RA, both on top of metformin. Participants received a 2‐h meal tolerance test before randomization and at study end (26 weeks), with timed plasma glucose and C‐peptide determinations. β‐cell function parameters were resolved using mathematical modelling. Results: In the GLP‐1RA group (n = 162), both body weight and glycated haemoglobin decreased at week 26, yet none of the insulin secretion/β‐cell function parameters changed significantly. In contrast, in the iGlarLixi group (n = 189), glycated haemoglobin decreased significantly more than in the GLP‐1RA group (p <.0001) despite an increase in body weight (+1.7 ± 3.9 kg, p <.0001). Fasting and stimulated insulin secretion decreased at Week 26 (both p <.0001 vs. GLP‐1RA), while β‐cell glucose sensitivity increased by a median 35% (p =.0032 vs. GLP‐1RA). The incremental meal tolerance test glucose area showed a larger reduction with iGlarLixi versus GLP‐1RA (p <.0001). Conclusions: In people with type 2 diabetes on metformin, 26‐week treatment with iGlarLixi resulted in a marked improvement in β‐cell function concomitant with sparing of endogenous insulin release and a reduction in meal absorption. [ABSTRACT FROM AUTHOR]