The effect of six weeks of endurance training on MMP-2 and MMP-9 in heart tissue of rats suffering from myocardial infarction

ABSTRACT
Introduction: Myocardial infarction is one of the leading causes of death and its most important consequences include loss of cardiac cells and severe deformation of the extracellular matrix components. Matrix metalloproteinases are a large group of protease enzymes that play an important role in this change, increasing the level of metal sites and causing heart disease and its consequences. While studies have shown that physical activity reduces cardiac fibrosis and improves cardiac disorders after infarction, and can reduce free radical levels, increase mitochondrial biogenesis and nitric oxide synthesis, and by increasing FGF21 activity, can reduce the level of negative and inflammatory factors, for this reason, the aim of the present study was to investigate the effect of six weeks of endurance training on matrix metalloproteinases 2 and 9 in rats with myocardial infarction.
Materials and Methods: In this controlled experimental study with a control group, 20 Wistar rats, eight weeks old and weighing 230±30 g, were randomly divided into two groups: endurance training + myocardial infarction and myocardial infarction after infarction induction with isoproterenol (150 mg/kg) subcutaneously. 24 hours after the induction of myocardial infarction, in order to confirm the stroke, blood samples were taken from the samples and transferred to the laboratory for troponin T analysis. An electrocardiogram test was also used to confirm the stroke, and both tests confirmed the myocardial infarction. The training group underwent an endurance training program intervention for six weeks, 3 sessions per week for 20 to 45 minutes at a speed of 13 to 18 meters per minute. 24 hours after the last training session and fasting and anesthesia using ketamine and xylazine, blood samples taken from the heart of the subjects were It was collected, transported to the laboratory, and examined using the ELISA method to assess serum MMP-2 and MMP-9 concentrations. To analyze the findings, the Shapiro-Wilk test and independent t-test were used with SPSS version 26 software, and Prism software was used to draw graphs. Also, a significance level of (P<0.05) was considered.
Findings: The results showed that endurance training reduced serum levels of MMP-2/9 in rats with MI accompanied by endurance training, but the reduction in the levels of these factors was not significant, and the weight of the training group decreased more than the control.
Conclusion: It seems that endurance training can reduce inflammation caused by heart attacks and reduce MMP-2/9 levels, but further studies should be conducted on the intensity and duration of training.
Keywords: Endurance training, matrix metalloproteinase-2, matrix metalloproteinase-9, isoproterenol, myocardial infarction