Branched-Chain Amino Acids Are Poor Markers of Insulin Resistance in Women: The Federal Womens Study

The data relating branched chain amino acids (BCAAs) with obesity and type 2 diabetes is conflicting but may be further clarified by examining its relationship to race/ethnicity and menopause. Therefore, we determined the relationship of BCAA with markers of insulin sensitivity (SI) in 122 federally employed women (49 White, 73 Black: 58 African American and 15 African Immigrant, age 44±10 (mean±SD) (range 24-62y); BMI 30.2±5.7 (range 20.3-45.2 kg/m2); 33% menopausal) using linear regression models adjusted for race and menopause. Fasting BCAAs were measured by nuclear magnetic resonance (NMR) spectroscopy, whole-body SI derived from the minimal model, basal hepatic insulin sensitivity (HISI) using [6,62H2]glucose, and hepatic and visceral adipose tissue (VAT) by proton NMR. BCAAs were similar in black and white women (leucine:104±30 vs. 114±37, valine:196±40 vs. 204±34, isoleucine:41±12 vs. 38±12 μmol/L, all P≥0.1) and did not differ by menopause (P\u003e0.5). Total and individual BCAAs were associated with lower whole-body SI (Figure), weakly associated with VAT (AdjR2=0.1, P=0.01), liver fat (AdjR2=0.01, P=0.01), and there was no association with HISI (P\u003e0.2). Overall, plasma BCAAs were not robust markers of insulin resistance in women of white or African ancestry and higher levels in women with insulin resistance may reflect a composite effect of dietary and metabolic processes. Disclosure S. Matta: None. C.K. Cravalho: None. A. Villalobos-Perez: None. A. Meyers: None. L. Mabundo: None. A.B. Courville: None. M.L. Sampson: None. A.E. Sumner: None. S.T. Chung: None. Funding National Institutes of Health (to S.T.C., L.M., A.B.C.)