1Associate Professor of Histology, School of Basic Sciences, Arak University, Arak, Iran
2Assistant Professor of Biochemistry, School of Basic Sciences, Arak University, Arak, Iran
3Master of Science in Cellular Developmental Biology, School of Basic Sciences, Arak University, Arak, Iran
4Assistant Professor of Anatomy, Shahid Sadooghi University of Medical Sciences, Yazd, Iran
5Associate Professor of Histology, School of Medicine, Ahwaz University of Medical Sciences, Ahwaz, Iran
6Master Student of Cellular Developmental Biology, School of Basic Sciences, Arak University, Arak, Iran
Background & Aims: Diabetes mellitus influences the reproductive system. Since investigations have showed that cinnamon may have an improving effect on diabetes, this study was designed to investigate the effect of cinnamon extract on the ovary structure in diabetic rats. Methods: A total of 24 female wistar rats (186±15gr) were randomly divided into 4 equal groups of control, control + cinnamon extract, diabetic and diabetic + cinnamon extract. Streptozotocin (60 mg/kg) was injected to induce diabetes and cinnamon extract (80 mg/kg/day) was administered orally through gavage. After 14 weeks, blood sugar and body weight were determined then rats were anesthetized and the right ovaries were taken out, weighed and underwent the process of slice preparation and staining by H&E method. The total volume of ovary, cortex and medulla, diameter of Graafian follicle and oocyte and thickness of zona pellucida were estimated by stereological methods. Data were analyzed using one way ANOVA and Tukey test. Results: Blood sugar was reduced significantly in diabetic +extract group compared with diabetic rats. Mean total volume of ovary, cortex and medulla were increased significantly in diabetic group compared with other groups. Mean total volume of ovary, cortex and medulla were the same in diabetic + extract, control and control + extract groups. Body weight in both diabetic groups was reduced significantly compared with control groups. Ovary weight in diabetic group showed a significant increase in comparison to that in the diabetic + extract group. Conclusion: Based on the results, water-alcohol extract of cinnamon causes reduction in blood glucose level and prevents increase in ovary weight and volume of ovary, cortex and medulla in diabetic rats.