Intramyocellular lipid accumulation and reduced whole body lipid oxidation in HIV lipodystrophy

Divisions of 4 Infectious Diseases, 5 Diagnostic Radiology, and 6 Nuclear Medicine, 2 Clinical Research Unit II, and 3 Clinical Spectroscopy Unit, San Raffaele Scientific Institute, and 1 International Center for Assessment of the Nutritional Status, Universita' degli Studi di Milano, 20132 Milan, Italy Antiretroviral therapy in human immunodeficiency virus (HIV)-positive patients can induce a lipodystrophy syndrome of peripheral fat wasting and central adiposity, dyslipidemia, and insulin resistance. To test whether in this syndrome insulin resistance is associated with abnormal muscle handling of fatty acids, 12 HIV-1 patients (8 females/4 males , age = 26 ± 2 yr, HIV duratio n = 8 ± 1 yr, body mass index = 22.0 ± 1.0 kg/m 2 , on protease inhibitors and nucleoside analog RT inhibitors) and 12 healthy subjects were studied. HIV-1 patients had a total body fat content (assessed by dual-energy X-ray absorptiometry) similar to that of controls (22 ± 1 vs. 23 ± 2%; P = 0.56), with a topographic fat redistribution characterized by reduced fat content in the legs (18 ± 2 vs. 32 ± 3%; P