Effect of aqueous extract of Cinnamomum verum on anxiety-like behavior in streptozotocin-induced diabetic male rats

Nowadays, herbal products often have been used as an alternative or supplement to chemical drugs in treat of diseases with low side effects and cost of treatment. The aim of this study was to survey the effect of aqueous extract of Cinnamon verum on anxiety-like behavior in streptozotocin-induced (STZ) diabetic rats.
This experimental study was carried out on 28 of male Wistar rats with the weight range of 200 ± 30 (g) in which randomly divided into four groups including seven each. The diabetes induced in adult male Wistar rats with an intraperitoneal injection of streptozotocin (50 mg/kg). The experiments were assigned to 3 weeks, rats were treated with extract in dose of 200mg/kg oral in which at the end of experiment animals were transferred to the elevated plus maze (EPM) at adjusted intervals and their anxiety reactions including enterance numbers and time spent in open arm were recorded and investigated in 5 min. The data were analyzed using SPSS software, method of One-way ANOVA and were compared different groups with each other by tukey test. Finally, P≤0/05 was considered statistically significant.
A significant decrease in entrance numbers and time spent in open arm of the elevated plus maze in groups of the treated diabetic rats were seen whereas; there were no significant changes in their anxiety reactions in other groups (non-diabetic)(P≤0.05).
It was thought in this survey, extract of Cinnamon verum with more than 50 different combinations and different effects, can affect nerve disorders of anxiety in adult male rats. But, the findings show that C. verum extract cannot effect on the anxiety-like behavior in adult male rats. However, the anxiety-like behavior increased in induced diabetic adult male rats, significantly. Therefore, it could be suggested that on the one hand probably the concentration of cinnamon used to treat diabetic rats was not sufficient to reduce blood glucose levels and improved effects did not have on the function of neurotransmitter systems for anxiety control. On the other hand, it is likely changes in the activity of neurotransmitter systems in the brain and the occurrence of anxiety behaviors in diabetic rats has been influenced by factors other than glucose levels. As a result, cinnamon extract had no effect on the improvement of anxiety and anxiety – like behaviors due to low blood glucose levels.