effect of exercise training on bcl-2 and bax gene expression in the rat heart

Background: 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. objectives: 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. materials and methods: 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). results: 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%). conclusions: 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.