Antidiabetic effects of cinnamon oil in diabetic KK-Ay mice

The hypoglycemic effect of cinnamon oil (CO) in a type 2 diabetic animal model (KK-Ay mice) was studied. The main component of CO was cinnamaldehyde, and other nineteen components were also determined. CO was administrated at doses of 25, 50 and 100 mg/kg for 35 days. It was found that fasting blood glucose concentration was significantly decreased (P < 0.05) with the 100 mg/kg group (P < 0.01) the most efficient compared with the diabetic control group. In addition, there was significant decrease in plasma C-peptide, serum triglyceride, total cholesterol and blood urea nitrogen levels while serum high density lipoprotein (HDL)-cholesterol levels were significantly increased after 35 days. Meanwhile, glucose tolerance was improved, and the immunoreactive of pancreatic islets β-cells was promoted. These results suggest that CO had a regulative role in blood glucose level and lipids, and improved the function of pancreatic islets. Cinnamon oil may be useful in the treatment of type 2 diabetes mellitus.