Objective: Circulating amino acids (AA) may serve as potential biomarkers for obesity and future type 2 diabetes (T2DM). In children and adolescents, the effects of obesity on circulating AAs are inconsistent. Data on the role of physical activity-based lifestyle (PAL) interventions on circulating AAs are also sparse. We aimed to address these gaps and determine the effect of obesity and PAL on circulating AAs in adolescents.

Method: Age (age,14-18 year) and maturity matched (Tanner stage>IV) adolescents with normal weight (NW, n=7) and obesity (OB, n=15) were studied at baseline; the 15 OB adolescents underwent a 3-month randomized controlled PAL intervention. AAs were measured using high performance liquid chromatography-based amino acid analyzer. Body composition by DXA and glucose, insulin, adiponectin, RBP4, hsCRP and IL-6 were measured and HOMA-IR calculated. Independent t-tests, analysis of covariance and mixed effect models were used for data analysis.

Results: Thirteen AAs were significantly (P<0.05) higher in the OB compared to the NW group. The branched chain AAs, leucine (28%), isoleucine (11%) and valine (17%) were higher (P<0.05) in the OB vs. NW. PAL intervention showed only negligible effects on AA concentration, except for glutamine and glycine; both deceased (P<0.05) post-intervention. Adiponectin increased and RBP4, hsCRP, IL-6 and HOMA-IR decreased (P<0.05 for all) post-intervention, but no correlation with changes in the concentration of AAs. BMI did not change; fat mass decreased; fat free mass increased (P<0.05).

Discussion: Obesity-related alterations in AAs warrant further studies to understand their role as potential biomarkers of obesity and T2DM in children. The post-PAL decrease in glutamine and glycine may suggest their increased demand by other organs in response to the intervention. Despite the beneficial changes in various metabolic factors, the lack of changes in several AAs is intriguing.

Disclosure

M. Hossain: None. D.E. George: None. P. Balagopal: None.

Funding

American Diabetes Association (1-14-CE-04 to P.B.B.); Nemours Biomedical Research

© 2019 by the American Diabetes Association.
2019
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