Acarbose improves indirectly both insulin resistance and secretion in obese type 2 diabetic patients.

BACKGROUND Acarbose is an oral antidiabetic mainly acting on postprandial blood glucose, inhibiting alphaglucosidase. Through this mechanism, it could improve the peripheral insulin sensitivity and/or increase the insulin secretion. The aim of the present study is to assess the therapeutic efficacy of Acarbose in obese type 2 diabetic patients on both insulin resistance and insulin secretion. METHODS 17 obese non insulin-dependent diabetic patients, well controlled with diet alone were randomized into 2 groups: acarbose (2 x 50 mg) or placebo during 16 weeks. A glucagon test allowed to evaluate insulin secretion before and after treatment as well as a triple test (glucose-insulin-somatostatin) with indirect calorimetry allowed to evaluate insulin sensitivity. RESULTS A significant improvement in post-prandial plasma glucose was detected only in the Acarbose group (8.0 +/- 0.5 mmol/l before vs 6.5 0.5 mmol/l after, p<0.05). Basal C-peptide secretion was similar between groups and remained unchanged after treatment. However, stimulated insulin secretion was significantly increased by 30%, p<0.05, in the Acarbose group while no change was detected in the placebo group. Interestingly, the group receiving Acarbose disclosed a 15% reduction in insulin resistance (15.0 +/- 1.8 mmol/l before vs 12.8 +/- 1.4 mmol/l after). CONCLUSIONS Our results show that a treatment with Acarbose is efficient even in diabetic patients presenting a good glucose control without any other associated treatment. By decreasing post-prandial blood glucose, acarbose improves both insulin sensitivity and secretion.