Background and Objective: Nowadays, the use of herbal products has been proposed as an alternative to chemical drugs.  Cinnamon is considered as a beneficial and useful herb. Due to the increasing demand of medicinal plants to treat diseases and identify any side effects on different organs, this study was performed to investigate the effects of aqueous extract of cinnamon on serum biochemical parameters in streptozotocin-induced (STZ) diabetic rats.

Materials and Methods:  21 male Wistar rats were assigned to three groups of 7 including control, diabetic control and diabetic rats treated with the extract, respectively. Fasting mice were diabolized with 50 mg/kg intraperitoneal injection of streptozotocin. After 21 days of treatment with the extract at a dose of 200 mg/ kg, blood sugar, triglycerides, cholesterol, HDL and LDL in serum were measured in three groups. Results were analyzed using one- way ANOVA and Tukey test.

Results: A significant decrease in blood glucose, triglycerides and cholesterol in the treated diabetic rats were seen whereas, there was no significant changes in LDL and HDL levels.

Conclusion: Since the plants in this family have flavonoid components, their effect on reduction of serum biochemical parameters including blood glucose, triglyceride and cholesterol may be due to these components. Therefore, the aqueous extract of cinnamon has anti-diabetic properties and its proper use is beneficial for diabetic patients.