Issue 139 Item 13 Repaglinide Affects Insulin Secretion and Oxidative Stress

After treatment with repaglinide, insulin secretion increased significantly during the first phase, but not during the second. A group of investigators from the Medical University in Sofia, Bulgaria, evaluated the effects of repaglinide on insulin secretion and oxidative stress in patients with type 2 diabetes. Forty-six patients who had been treated with diet modifications or metformin received repaglinide plus their original treatment. A control group of 29 patients continued to receive diet modifications or metformin. The investigators studied phases of insulin secretion during an intravenous glucose tolerance test. Oxidative stress was assessed by total serum antioxidant capacity and serum superoxide dismutase activity.

The investigators showed that the concentrations of HbA1c decreased significantly after treatment with repaglinide and the difference was significantly greater than that in the control group. After treatment with repaglinide, insulin secretion increased significantly during the first phase, but not during the second. Insulin secretion was unchanged in the control group after 2 months. There was a significant increase in total serum antioxidant capacity and serum superoxide dismutase activity after treatment with repaglinide, and this increase was significantly greater than that in the control group. The investigators conclude that repaglinide increases insulin secretion during the first phase; this increase is the main defect of beta-cells in patients with type 2 diabetes. Repaglinide also has a beneficial effect on oxidative stress. Diabetes Research and Clinical Practice 2003;59:43-9