Intramyocellular Lipid and Insulin Resistance: Differential Relationships in European and African Americans
Autor: | Dana Y. Rigsby, Robert Lopez-Ben, W. Timothy Garvey, Katherine H. Ingram, T. Mark Beasley, Barbara A. Gower, David B. Allison, A. Julian Munoz, Cristina Lara-Castro, Bradley R. Newcomer, Jeannine C. Lawrence, Robert Makowsky |
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Rok vydání: | 2011 |
Předmět: |
Adult
medicine.medical_specialty Magnetic Resonance Spectroscopy Waist Endocrinology Diabetes and Metabolism African descent Muscle Fibers Skeletal Abdominal Fat Medicine (miscellaneous) Article White People Body Mass Index Young Adult Absorptiometry Photon Endocrinology Insulin resistance Risk Factors Internal medicine Humans Medicine Obesity Adiposity Metabolic Syndrome Nutrition and Dietetics business.industry Insulin sensitivity Lipid metabolism Middle Aged Lipid Metabolism medicine.disease United States Black or African American Cross-Sectional Studies Obesity Abdominal Insulin Resistance Metabolic syndrome business Body mass index |
Zdroj: | Obesity. 19:1469-1475 |
ISSN: | 1930-7381 |
DOI: | 10.1038/oby.2011.45 |
Popis: | Insulin resistance has been associated with the accumulation of fat within skeletal muscle fibers as intramyocellular lipid (IMCL). Here, we have examined in a cross-sectional study the interrelationships among IMCL, insulin sensitivity, and adiposity in European Americans (EAs) and African Americans (AAs). In 43 EA and 43 AA subjects, we measured soleus IMCL content with proton-magnetic resonance spectroscopy, insulin sensitivity with hyperinsulinemic–euglycemic clamp, and body composition with dual-energy X-ray absorptiometry. The AA and EA subgroups had similar IMCL content, insulin sensitivity, and percent fat, but only in EA was IMCL correlated with insulin sensitivity (r = −0.47, P < 0.01), BMI (r = 0.56, P < 0.01), percent fat (r = 0.35, P < 0.05), trunk fat (r = 0.47, P < 0.01), leg fat (r = 0.40, P < 0.05), and waist and hip circumferences (r = 0.54 and 0.55, respectively, P < 0.01). In a multiple regression model including IMCL, race, and a race by IMCL interaction, the interaction was found to be a significant predictor (t = 1.69, DF = 1, P = 0.0422). IMCL is related to insulin sensitivity and adiposity in EA but not in AA, suggesting that IMCL may not function as a pathophysiological factor in individuals of African descent. These results highlight ethnic differences in the determinants of insulin sensitivity and in the pathogenesis of the metabolic syndrome trait cluster. |
Databáze: | OpenAIRE |
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