Changes in insulin resistance are related to liraglutide-induced HMW-Adiponectin increase in obese type 2 diabetes

Liraglutide treatment could improve insulin resistance, while the underlying mechanism is not completely understood. Adiponection is a key component in the interrelationship between adiposity and insulin resistance, while the high molecular weight (HMW) adiponectin is the main active form. In this study we tested the hypothesis that the reduction of insulin resistance was associated with increase plasma HMW adiponectin mediated by liraglutide. A total of 45 obese type 2 diabetic patients were included in the 12-week observational, self-controlled clinical study. They were subcutaneously injected with liraglutide once daily as an add-on therapy based on their previous oral antidiabetic agents except for thiazolidinediones (TZDs). HOMA2-IR was calculated with serum glucose and C-peptide values using the validated calculator to evaluate changes of insulin resistance. Serum HMW-adiponectin concentration was tested by commercial ELISA Kit quantitatively. HOMA2-IR was significantly reduced, from baseline of 3.17 +/- 1.15 to 2.39 (1.89). There were positive correlations between d FBG, post-HOMA2-IR, delta weight and d HOMA2-IR. And there were inverse correlations between pre-treatment HOMA2-IR, delta HMW-APN and delta HOMA2-IR. By stepwise multivariate regression analysis, delta HOMA2-IR was predicted by delta HMW-APN. Insulin resistance was significantly improved after 12-week liraglutide treatment. Increased plasma HMW-adiponectin may play an important role in liraglutide-induced insulin sensitivity improving in obese type 2 diabetic patients.