Effects of rosiglitazone and metformin on liver fat content, hepatic insulin resistance, insulin clearance, and gene expression in adipose tissue in patients with type 2 diabetes

Abstract

Both rosiglitazone and metformin increase hepatic insulin sensitivity, but their mechanism of action has not been compared in humans. The objective of this study was to compare the effects of rosiglitazone and metformin treat-ment on liver fat content, hepatic insulin sensitivity, insulin clearance, and gene expression in adipose tissue and serum adiponectin concentrations in type 2 diabetes. A total of 20 drug-naive patients with type 2 diabetes (age 48 3 years, fasting plasma glucose 152 9 mg/dl, BMI 30.6 0.8 kg/m2) were treated in a double-blind random-ized fashion with either 8 mg rosiglitazone or 2 g met-formin for 16 weeks. Both drugs similarly decreased HbA1c, insulin, and free fatty acid concentrations. Body weight decreased in the metformin (84 4 vs. 82 4 kg, P < 0.05) but not the rosiglitazone group. Liver fa