Abstract
Background. Endoplasmic reticulum stress contributes to the development of cardiovascular diseases. In contrast, regular physical exercise has been considered a powerful tool to prevent and control cardiovascular diseases. Ischemic preconditioning has a protective effect against myocardial injury; however, its effects remain unclear when combined with exercise training. The present study aimed to investigate the effect of aerobic training and remote ischemic preconditioning on myocardial BIP and eIF2α gene expression in male rats with myocardial infarction.
Methods. In this experimental research, a total of 25 male Wistar rats were randomly divided into five groups: control, infarction, infarction ischemia, infarction aerobic training, and infarction ischemia + training. Myocardial infarction was induced by injection of Isoproterenol (100 mg/kg.day) for two consecutive days. Remote ischemic preconditioning was conducted by tightening a tourniquet around the upper thighs and included three 5-minute cycles of ischemia, followed by 5 minutes of reperfusion. The aerobic training was performed 5 sessions per week for 8 weeks. BIP and eIF2α gene expression was measured by RT-PCR method. Data were analyzed using one-way ANOVA test.
Results. BIP and eIF2α gene expression significantly increased in the infarction group compared to the control group (P≤0.01). There was a significant decrease in BIP and eIF2α gene expression in ischemia, aerobic training, and ischemia+training groups compared to the infarction group (P≤0.01).
Conclusion. It seems that remote ischemic preconditioning and aerobic exercise reduce cardiac BIP and eIF2α gene expression in mice with myocardial infarction; however, aerobic exercise combined with remote ischemic preconditioning is more effective.
Practical Implications. The use of remote ischemic preconditioning combined with aerobic exercise may exert a cardioprotective effect against cardiac injuries by mitigating endoplasmic reticulum stress in the heart.