Effect of endurance training with cinnamon bark extract on antioxidant activity levels and cardiac index in streptozotocin- (STZ) induced DM male rats

Background: Diabetes may be associated with an imbalance between the protective effects of antioxidants and increased production of free radicals. Oxidative stress also appears to contribute to the pathogenesis of diabetic complications. In this study the effect of endurance exercise with cinnamon bark extract on antioxidant activity levels and cardiac index in streptozotocin- (STZ) induced DM in male rats were investigated. Materials and Methods: In this experimental study, 50 male Wistar rats weight: 200-232 g were randomly divided into 5 groups (n=10): 1. Healthy control (CO), 2. Diabetic control (CD), 3. Diabetic + cinnamon extract treatment (D+CZ), 4. Diabetic + exercise training (D+EX), 5. Diabetic + cinnamon extract treatment + exercise training (D+EX+CZ). In D+EX+CZ group, the animals practiced endurance training for 8 weeks after becoming diabetic, and at the same times each rat has received 200 mg/kg cinnamon hydro alcoholic extract by gavage daily for 8 weeks. Results: Exercise training in D+EX and D+EX+CZ significantly prevented the decrease in heart weight compared to DC and D+CZ groups. The activity of the antioxidant enzyme (catalase) in the D+EX+CZ group increased significantly compared to the control group. Superoxide dismutase also increased significantly in all groups compared to the control group. Also, the activity of GPX enzyme (glutathione peroxidase) in D+EX+CZ and D+CZ groups showed a significant increase compared to the control group. Conclusion: The increased GPX, CAT and SOD activity and prevented the decrease in heart weight induced by combined intervention of cinnamon extract and endurance training may attenuate oxidative stress in diabetic rats