Distribution of subcutaneous fat predicts insulin action in obesity in sex-specific manner.
The pattern of adipose tissue (AT) distribution is an important predictor of metabolic risk. The aim of this study was to analyze the association of peripheral (insulin-mediated glucose disposal--M) and hepatic (suppression of endogenous glucose production--EGP) insulin action with abdominal (subcutaneous abdominal AT-SAAT intraabdominal AT-IAAT) and thigh AT depots in obese individuals. Fifty-seven Pima Indians with normal glucose tolerance underwent magnetic resonance imaging (MRI) and euglycemic-hyperinsulinemic clamp. M was negatively related to intraperitoneal IAAT (P = 0.02) and deep SAAT (P = 0.03). Suppression of EGP was negatively related to total (P < 0.05) or deep SAAT (P < 0.05 and P = 0.01, respectively), and total or intraperitoneal IAAT (P = 0.009 and P = 0.002, respectively). A significant interaction with sex was found in the association between superficial SAAT and M, so that in women, but not men, M negatively correlated with superficial SAAT (P = 0.02). In stepwise regression analysis, both M (r2 = 0.09) and EGP suppression (r2 = 0.17) were associated only with intraperitoneal IAAT in the whole group. In the sex-specific analysis (because of the significant interaction), lower M was associated with higher deep SAAT (r2 = 0.15) in combination with lower superficial SAAT (r2 = 0.09) in men, and with higher superficial SAAT (r2 = 0.29) in combination with lower thigh subcutaneous AT (r2 = 0.16) in women. Although intraperitoneal IAAT and deep SAAT were major predictors of peripheral and hepatic insulin action in obese Pima Indians, the largest variance in M rate was explained in a sex-specific manner by relative size of subcutaneous AT depots.
Koska
Juraj
J
Obesity and Diabetes Clinical Research Section, NIDDK/NIH/DHHS, Phoenix, Arizona, USA.
Stefan
Norbert
N
Votruba
Susanne B
SB
Smith
Steven R
SR
Krakoff
Jonathan
J
Bunt
Joy C
JC
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000502:physiology; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D007198:Indians, North American; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D008297:Male; D009765:Obesity / Q000097:blood / Q000378:metabolism*; D011237:Predictive Value of Tests; D012737:Sex Factors; D018709:Statistics, Nonparametric; D050151:Subcutaneous Fat / Q000378:metabolism*; D050507:Subcutaneous Fat, Abdominal / Q000378:metabolism*; D055815:Young Adult
D001786:Blood Glucose; D007328:Insulin