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>0.5). 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>0.2). 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.
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.
National Institutes of Health (to S.T.C., L.M., A.B.C.)
