Preconditioning by the exercise and curcumin protects left ventricular myocardium against ischemia-reperfusion injury and suppresses ventricular arrhythmias in rats

Introduction: The present study examined the effects of a 10-week preconditioning with moderateintensity aerobic exercise and curcumin supplementation before ischemia-reperfusion (IR) to investigate if this method contributes to the protection of cardiac myocardium against IR-induced injury and left ventricular dysfunction in rat. Materials and Methods: Male Wistar rats (6-8 weeks old) were randomly assigned to the 5 groups (each with 10 rats), sedentary-control (Sed-CON), sedentary ischemia-reperfusion (Sed-IR), exercise with IR (Ex-IR), curcumin with IR (Cu-IR), and both exercise and curcumin with IR (Ex-Cu-IR). Exercise intervention performed five times a week for 10 weeks. After the training period, arrhythmias and electrocardiogram parameters, factors involved in cardiac structure and function, and infarct size of myocardium were investigated. Results: We observed that a 10-week moderate-intensity aerobic exercise (15-45 min at 12-24 m/min) five sessions a week as well as curcumin supplementation (50 mg/kg) over the mentioned period, in advance to IR, significantly decreased IR-induced infarct size in Ex-IR, Cu-IR, and Ex-Cu-IR groups compared to Sed-IR (P = 0.0001), alleviated arrhythmia by reduction in ventricular ectopic beats episodes in Ex-IR, Cu-IR, and Ex-Cu-IR groups compared to Sed-IR (P = 0.001), decreased ventricular tachycardia episods in Ex-IR, Cu-IR, and Ex-Cu-IR groups in comparison to that of Sed-IR group (P = 0.001) and improved cardiac function (P = 0.001). Conclusion: According to our findings, exercise has superior cardioprotective effects than curcumin. The combination of curcumin and exercise has no preference on exercise or curcumin alone. Hence both long-term aerobic exercise and curcumin supplementation are effective cardioprotectors against IRinduced injury.