Improved Cardiac Function Following Ischemia Reperfusion Injury Using Exercise Preconditioning and L-Arginine Supplementation via Oxidative Stress Mitigation and Angiogenesis Amelioration

Abstract

The formation of new blood vessels in the ischemic area is a fundamental strategy that can reduce myocardial infarction-induced damage by mitigating hypoxia. This paper set out to investigate the cardioprotective effect of high-intensity interval training preconditioning and L-arginine supplementation on myocardial ischemia-reperfusion-induced angiogenesis and oxidative stress. 50 male rats were randomly distributed into following groups: (1) Sham, (2) Sedentary control (Con, n = 10), 3) L-arginine treatment (La, n = 10), (4) High-Intensity Interval Training (HIIT, n = 10), and High-Intensity Interval Training plus L-arginine supplementation (HIIT + La, n = 10). Rats in the training groups performed high-intensity interval training for 8weeks (5day per week). Subjects in La and HIIT + La groups received L-arginine in drinking water (4g/L). 72h after treatments, all subjects underwent myocardial ischemia-reperfusion operation. Cardiac function, angiogenesis, stress oxidative, and infarction size were measured after reperfusion. Results showed exercise training and L-arginine supplementation promoted Cat and GSH activities and decreased MDA activity following myocardial ischemia-reperfusion injury in non-infarcted area. Compared with the con group, VEGF and Ang-1 as well as Ang-1 to Ang-2 ratio following myocardial ischemia-reperfusion in the non-infarct area were higher in La + HIIT group. Meanwhile, capillary density and capillary-to-muscle fiber ratio were higher in response to training and L-arginine supplementation. HIIT and L-arginine alone and synergistically decreased ischemia-reperfusion-induced infarction size. Cardiac output and stroke volume ameliorate in response to exercise training and L-arginine supplementation. Taken together, exercise preconditioning and l-arginine supplementation improved left ventricular function following ischemia-reperfusion by stress oxidative mitigation and angiogenesis amelioration.