The effect of cinnamon on glucose concentration of diabetic rats in presence or absence of insulin

Abstract Background: Some plants and their aqueous extracts are used as traditional treatments for diabetes. Cinnamon as a preferred candidate shows anti-diabetic and hypoglycemic effects. Objective: To determine the effect of cinnamon extract on blood glucose level of diabetic rats. Methods: The present work was an experimental study in which seventy NMRI male rats (180-250gr) were divided into 2 major groups named as normal and diabetic group. Normal group was further subdivided as control, cinnamon and insulin subgroups in which the latter two received suspensions of cinnamon 60mg/kg per day and intraperitoneal injections of insulin (5μg/kg), respectively. In four diabetic subgroups, diabetes was induced by ip injection of streptozotocin (40mg/kg). These groups were marked as diabetic control, diabetic/cinnamon, diabetic/insulin and cinnamon plus insulin subgroups. Findings: Our results showed that the oral administration of cinnamon had not significant effect on normal cinnamon subgroup. Insulin injection in normal rats reduced glucose concentration from 99.1 to 52.1 mg/dl. Glucose concentration in diabetic groups with treatment of cinnamon, Insulin and both of them were measured 121.6, 69.6 and 41.4 mg/dl, respectively. Reduction of glucose concentration in these subgroups show asignificant change in comparison with control diabetic subgroup, 366.5 mg/dl (p<0.001). Conclusion: Cinnamon can reduce blood glucose concentration in diabetic rats and it seems that the cinnamon effect to be probably linked with potentiating action of cinnamon on insulin.