عنوان

تأثیر سه ماه تمرین هوازی با و بدون محدودیت غذایی بر آپوپتوز میوکارد موش‌های صحرایی

Text of Note

Background: Exercise training and dietary restriction are practical interventions for weight loss and increasing lifespan. Nonetheless, little is known about the signaling pathways underlying anti-aging and anti-apoptotic effects of exercise training and dietary restriction, especially in sensitive somatic tissues such as myocard. Therefore, the purpose of this study was to investigate the effect of three months aerobic training with and without dietary restriction on some indices of myocardial apoptosis in rats. Material and methods: This study was conducted as experimental design (animal model) with control groups. Forty-eight 3-month-old male rats were randomly divided into five homogenous groups including: 1- three months old Control (Conb; n=8), 2- six months old Control (Con; n=10), 3- Dietary restriction (DR; n=10), 4- Exercise training (ET; n=10) and 5- Exercise training+dietary restricition (ET+DR; n=10). All groups, except Conb, participated in the study for 3 months. Animals in Con and ET groups were fed ad libitum (0 DR) while animals in DR and ET+DR group were given access to 50 of the control animals diet (-50 DR). Animals in ET and ET+DR underwent 3 months aerobic training program (5days per week, 10-60 mins, 24-33 mind-1, 15 incline). Forty-eight hours after the last exercise session all animals were sacrificed and the heart was removed and dissect to separate the left ventricle (LV). LV was analyzed for mRNA of caspase-3, Bax, Bcl2, beta-catenin and glycogen synthase kinase-3 beta using RT-PCR method. Data were analyzed using Two-way ANOVA test and the significant level was set at P<0.05. Results: The results of the present study showed that effects of aerobic training and dietary restriction separately and in interaction with each other on caspase-3 gene expression were not significant (P>0.05). However, lowering effect of aerobic training with or without dietary restriction on Bax gene expression and Bax/Bcl-2 was significant (P<0.05). Although, effect of dietary restriction on the expression of these indices was not significant (P>0.05). Meanwhile, additive effect of aerobic training and dietary restriction in interaction with each other on Bcl-2 gene expression were significant (P<0.05). However, effects of aerobic training and dietary restriction separately on Bcl-2 gene expression were not significant (P>0.05). Also, effect of aerobic training on beta-catenin gene expression was significant (P<0.05) but effect of dietary restriction alone and in interaction with aerobic training on beta-catenin gene expression was not significant (P>0.05). Finally, the results showed that increasing effect of dietary restriction separately and in interaction with aerobic training were significant (P<0.05). However, additive effect of aerobic training was negligible (P>0.05). Conclusion: Overall, it seems that three months aerobic training can remarkably reduce pro-apoptotic genes expression and Bax/Bcl-2 and increase beta-catenin genes expression which may provide a suitable environment for myocardial cells survival and modulation of apoptosis. Meanwhile, the combination of exercise training and dietary led to remarkable increase in anti-apoptotice Bcl-2 gene expression. Therefore, it is likely that aerobic training along with dietary restriction enhances mitochondrial membrane integration and reduces apoptotic damage but have no significant effect on caspase-related mechanisms. However, more researches are needed to identify the relationship between thes indices and the effect of various conditions