Abstract

Longitudinal Profiling of Amino Acids Metabolism with Respect to Markers for Disturbed Glucose and Insulin Homeostasis in Obese Children

Christian Hellmuth, Post-Doc, Ludwig-Maximilians-University of Munich

In obese children, most adverse metabolic consequences are mediated through cardiovascular risk factors, like hyperinsulinaemia. Branched-chain amino acids (BCAA) and acylcarnitines (Carn) involved in amino acid (AA) degradation were linked to obesity-associated insulin resistance (IR). These associations have not been studied longitudinally. Therefore, we analyzed HOMA, AA, and Carn in 80 initially obese children from the Obeldicks lifestyle intervention cohort of whom 40 had substantial weight loss (decrease >0.5 standard deviation scores of BMI during the 1-year-intervention) and 40 had no weight loss. Associations of BMI adjusted metabolite levels to the clinical markers were considered at baseline, end, and as change during the intervention period. In all initially obese children, only tyrosine was significantly and positively associated with HOMA at baseline, end, and as change during the intervention (p<0.05). Stratified analysis revealed that the 40 children with substantial weight loss mainly drove this association. BCAA and short-chain Carn were negatively associated with HOMA-IR at baseline (p<0.05), but not in the longitudinal profiling. This longitudinal study revealed a positive association between the aromatic AA tyrosine to IR, rather than BCAA. Furthermore, we unveiled that not one but different mechanisms seem to be involved in IR development.