The Effect of Aerobic Training on Gene Expression of a Main Marker of Mitophagy (Parkin) in Old Male Rats

Physical activity can protect against some age-associated complications such as sarcopenia (۱). It has been established that mitochondrial turnover including mitogenesis and mitophagy are impaired by aging (۲) which may be due to a decline in physical activity in old age (۳). Parkin is an E۳ ubiquitin ligase that is partially responsible for mitophagy (۴). However, the changes in Parkin levels in aging has not well known. Importantly, the role of exercise training in improving or preventing aging-induced changes of Parkin has not been determined.. Therefore, this study aimed to investigate the impact of aerobic training on Parkin gene expression in skeletal muscle of old male rats.Eight young male Wistar rats with eight to ten weeks of age and mean of ۳۲۰ g in weight, and also ۱۶ old rats with ۱۶ to ۱۸ months of age and mean of ۴۵۰ g in weight were provided in the Biotechnology Center of Yazd Shahid Sadoughi University of Medical Sciences. Young rats were considered as Young-Control (n=۸). The old rats were divided into Old-Control (n=۸) and Old-Training (n=۸). Old-Training rats were subjected to an aerobic training on a treadmill with ۱۰° inclination for eight weeks (۵ days per week). Rats run ۳۰ min by ۷۰% vVo۲peak per session of training. The rats were sacrificed by injection of Ketamine-Xylazine mixture following ۴۸ h after the final training session, and Soleus muscle was taken for examination. The gene expression of Parkin was determined by Real-Time PCR.The Old-Control displayed lower levels of gene expression of Parkin as compared to Young-Control (near ۳ fold; P=۰.۰۲). Interestingly, the Parkin expression in the Old Training group was not significantly lower than Young-Control (near ۱.۶-fold; P=۰.۰۹). Moreover, Parkin expressions were not significantly higher in Old-Training compared to Old-Control (near ۱.۴-fold; P=۰.۱۱).The results indicated that Parkin expression, as a mitophagy marker, was reduced by aging. Interestingly, aerobic training could negate the reducing effect of aging in Parkin expression. These would suggest that aerobic training may prevent the old-inducing loss of mitophagy in skeletal muscle.

کلیدواژه ها:

Mitophagy ، Parkin ، aging ، Aerobic training