Distribution of subcutaneous fat predicts insulin action in obesity in sex-specific manner

Obesity (Silver Spring). 2008 Sep;16(9):2003-9. doi: 10.1038/oby.2008.292.

Abstract

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.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Adult
  • Blood Glucose / metabolism
  • Body Composition / physiology
  • Female
  • Glucose Clamp Technique
  • Glucose Tolerance Test
  • Humans
  • Indians, North American
  • Insulin / blood
  • Insulin / metabolism*
  • Intra-Abdominal Fat / metabolism*
  • Magnetic Resonance Imaging
  • Male
  • Obesity / blood
  • Obesity / metabolism*
  • Predictive Value of Tests
  • Sex Factors
  • Statistics, Nonparametric
  • Subcutaneous Fat / metabolism*
  • Subcutaneous Fat, Abdominal / metabolism*
  • Young Adult

Substances

  • Blood Glucose
  • Insulin