Effects of rosiglitazone and metformin on postprandial paraoxonase-1 and monocyte chemoattractant protein-1 in human immunodeficiency virus-infected patients with lipodystrophy.

Highly active antiretroviral therapy in Human Immunodeficiency Virus (HIV) has been associated with lipodystrophy, insulin resistance and atherosclerosis. We investigated the effects of rosiglitazone or metformin on fasting and postprandial inflammatory and antioxidant variables in HIV-infected males with lipodystrophy. Thirty-one patients were randomly assigned to receive either rosiglitazone (4 mg twice daily) or metformin (1 g twice daily) for 26 weeks. At baseline and after treatment, standardized 10-h oral fat loading tests were performed. Before treatment, inflammatory variables remained unchanged but there was a postprandial decrease in high density lipoprotein (HDL)-cholesterol and paraoxonase (PON1) activity. Rosiglitazone and metformin reduced homeostasis model assessment index (HOMA) similarly (-34% and -37%, respectively, P<0.05 for each). Both treatments increased fasting and postprandial PON1 activity and decreased postprandial monocyte chemoattractant protein 1 (MCP-1) concentrations. However, plasma C-reactive protein (CRP) and Interleukin-6 (IL-6) concentration did not change throughout the study. To decrease insulin resistance results in a higher anti-oxidant and consequent lower pro-inflammatory action of HDL. This may confer protection against accelerated atherosclerosis in these patients.