Branched-chain α-keto acids and glutamate/glutamine: Biomarkers of insulin resistance in childhood obesity.

Objectives: Insulin resistance (IR) in adolescents with obesity is associated with a sex-dependent metabolic 'signature' comprising the branched-chain amino acids (BCAAs), glutamate/glutamine, C3/C5 acylcarnitines and uric acid. Here, we compared the levels of branched-chain α-keto acids (BCKAs) and glutamate/glutamine, which are the byproducts of BCAA catabolism and uric acid among adolescents with obesity prior to and following a 6-month lifestyle-intervention program.

Methods: Fasting plasma samples from 33 adolescents with obesity (16 males, 17 females, aged 12-18 year) were analysed by flow-injection tandem MS and LC-MS/MS.

Impact of lifestyle Intervention on branched-chain amino acid catabolism and insulin sensitivity in adolescents with obesity.

Unlabelled: Insulin resistance in adolescents with obesity associates with a sex-dependent metabolic 'signature' comprising branched-chain amino acids (BCAAs), glutamate and C3/C5 acylcarnitines (C3/C5), implicating altered flux through BCAA catabolic pathways. Here, we investigated the effects of lifestyle intervention on BCAA catabolism and insulin sensitivity. We hypothesized (1) weight reduction and improved insulin sensitivity associate with enhanced BCAA catabolism; (2) baseline BCAAs and their metabolic by-products predict changes in weight and insulin sensitivity during lifestyle intervention.

The 24-hour average concentration of cortisol is elevated in obese African-American youth with type 2 diabetes.

Introduction: 24-h average (IC) plasma concentrations of cortisol and growth hormone are lower in obese youth and adults without Type 2 diabetes (T2D) compared to lean subjects. Here we examined IC-cortisol and IC-growth hormone levels in obese youth with and without T2D.

Methods: We pooled ½-hourly samples from 20 to 24-hour sampling to create an IC for cortisol, cortisone, C-peptide, insulin, growth hormone and cortisol-binding-globulin in obese African-American youth with (n = 8) and without T2D (N = 9).

Macronutrient Regulation of Ghrelin and Peptide YY in Pediatric Obesity and Prader-Willi Syndrome.

Background: The roles of macronutrients and GH in the regulation of food intake in pediatric obesity and Prader-Willi Syndrome (PWS) are poorly understood.

Objective: We compared effects of high-carbohydrate (HC) and high-fat (HF) meals and GH therapy on ghrelin, insulin, peptide YY (PYY), and insulin sensitivity in children with PWS and body mass index (BMI) -matched obese controls (OCs).

Methods: In a randomized, crossover study, 14 PWS (median, 11.

Sex differences in biomarkers associated with insulin resistance in obese adolescents: metabolomic profiling and principal components analysis.

Objective: Obesity and insulin resistance (IR) predispose to type 2 diabetes mellitus. Yet only half of obese adolescents have IR and far fewer progress to type 2 diabetes mellitus. We hypothesized that amino acid and fatty acid metabolites may serve as biomarkers or determinants of IR in obese teens.

Relationship of body mass index and GAD65 antibody status on β-cell secretion at diabetes onset in African-American children.

Abstract Body mass and anti-pancreatic antibody status potentially influences the presentation of diabetes in children. We hypothesized that anti-pancreatic auto-antibody positive patients with new onset diabetes would have lower levels of insulin and C-peptide at presentation, and hence higher HbA1c. Records of children with new onset diabetes self-identified as African American were retrospectively analyzed.