The capability of glucose toxicity on severe type 2 diabetes.

The underlying defects of type 2 diabetes are impaired insulin sensitivity and decreased beta-cell function. In poorly controlled type 2 diabetes, the 'glucose toxicity' further deteriorates these defects. The objective was to determine whether correction of glucose toxicity will lead to improve insulin sensitivity and beta-cell function in these severely affected patients. Twelve severe type 2 diabetic patients were enrolled. An intravenous glucose tolerance test was performed before and after treatment with insulin for 3 months. The insulin sensitivity, glucose sensitivity, and acute insulin response after glucose loading were calculated by a minimal model algorithm. The lipid profiles did not change significantly after insulin therapy, but the hemoglobin A1c, level improved significantly (12.2 +/- 2.2% to 9.2 +/- 1.9%; p = 0.001). The insulin sensitivity, glucose sensitivity, and acute insulin response did not change significantly with insulin therapy. Correction of hyperglycemia with 3-month insulin therapy may improve metabolic effect instead of insulin sensitivity, glucose sensitivity, and acute insulin response to glucose load in severe type 2 diabetic patients.