Antidiabetic activity of Croton klozchianus in rats and direct stimulation of insulin secretion in-vitro.

Croton klozchianus is a relatively uninvestigated species with no pharmacological or phytochemical reports available, although it has been used clinically by Ayurvedic physicians to treat diabetes. We have investigated this use by studying the insulin secretion and antidiabetic activity of C. klozchianus. Treatment of diabetic rats with aerial parts of C. klozchianus extract (CK, 100 and 300 mg kg(-1) body weight) for three weeks showed significant reduction in blood glucose (45.8% after 14 days for 300 mg kg(-1)). C. klozchianus extract caused a significant concentration-dependent increase in insulin secretion (8-fold at 2 mg mL(-1) for cells challenged with 20 mM glucose) from MIN6 cells grown as monolayers and as pseudoislets, indicating that the antidiabetic activity may have been as a result of increased insulin secretion. It also had a role on the lipid profile of the rats by causing reduction in cholesterol and triglycerides and increasing high density lipoprotein significantly. The results obtained gave some scientific support to the traditional use of the plant as a treatment for diabetes.