Effect of Exercise Training on Bcl-2 and Bax Gene Expression in the Rat Heart

Apoptosis or programmed cell death plays an important role in the development of cardiovascular diseases, particularly heart failure. Current evidence suggests that exercise training may alter apoptosis-related signaling in sensitive somatic tissues such as the myocardium.. The aim of this study was to assess the effect of exercise training on Bcl-2 and Bax genes expression as key molecules involved in intrinsic pathway of apoptosis in the rat heart.. This study was conducted with a two-group experimental design (animal model) and sixteen three-month-old male rats were selected and randomly divided to two groups of exercise training (n = 8) and control (n = 8). Rats in the trained group participated in an exercise training program for 12 weeks (10 – 60 m min-1, 24 – 33 min d-1, 15%). The rat hearts were removed forty-eight hours after the last training session. RNA extraction and synthesis of cDNA was done, and Bax and Bcl2 genes expression was analyzed through the Real Time-Polymerase Chain Reaction (RT-PCR). Kolmogorov-Smirnov and independent t-test were applied for statistical analysis of the data (P < 0.05).. The results showed that Bax gene expression and Bax/Bcl2 ratio of the trained group were significantly lower than the control group, 81% and 89%, respectively (P < 0.05). Moreover, there was no significant difference between the two groups in Bcl2 (P > 0.05). However, Bcl2 expression was higher in the trained group compared to the control group (11%).. In general, it seems that three-month exercise training was effective in reducing cardiac mitochondrial pro-apoptotic protein. However, considering the results of the Bcl2 gene expression, more researches are needed to identify effects of exercise trainings on indices of myocardial apoptosis..