Effect of metformin therapy on plasma adiponectin and leptin levels in obese and insulin resistant postmenopausal females with type 2 diabetes.

To investigate the relative role of the adiponectin and leptin in the insulin resistance (IR) and obesity we studied plasma levels of these adipocytokines in obese and insulin resistant postmenopausal (PM) females with type 2 diabetes (DM2) during 6 months of Metformin therapy. We recruited 26 PM women, between the ages of 50 and 67 (59,7+/-8,1 years). These women had a BMI of 36,6+/-1,8 kg/m2. After baseline measurements Metformin therapy has been initiated (1700+/-2550 mg per day). Duration of therapy was 6 months. The results of investigations of adipocytokines after Metformin 6 months therapy shown that circulating adiponectin levels were significantly increased (19,1+/-6,0 vs. 16,1+/-3,9 ng/ml, p=0,008) together with significant reduction of BMI (35,9+/-1,9 vs. 36,6+/-1,8 kg/m2, p=0,005) and IR (3,05+/-0,89 vs. 3,96+/-0,70, p<0,001). The magnitude of the change in adiponectin levels positively correlated with the magnitude of BMI reduction (r=0,4784, p=0,013) and IR reduction (r=0,5779, p=0,002). Any significant correlation did not observed between changes of leptin levels and BMI, leptin levels and IR. In summary, our data suggest that hypoadiponectinemia in PM may be explained by only IR because the amelioration of whole-body insulin action by 6-month Metformin therapy leads to increase of plasma adiponectin levels; leptin levels did not significantly change after 6-month Metformin therapy.