The Effect of High-Intensity Interval Training on Mitochondria Fission-Related Factors in Skeletal Muscle of Old Wistar Rats
Paper ID : 1030-SSRC-13TH
Authors
Saeed Daneshyar *1, Yazdan Fourotan2
1Department of Physical Education, Faculty of Humanities, University of Ayatollah Alozma Boroujerdi
2Department of Physical Education and Sport Sciences, Islamic Azad University of Hamedan
Abstract
Background: Healthy mitochondrial dynamics are controlled by a regulated balance between mitochondrial fusion and fission. An imbalance between the fusion and fission processes in skeletal muscle mitochondria has been reported by aging (2). The mitochondrial fission is regulated by dynamin-related protein 1 (Drp1) and fission protein 1 (Fis1) (1).
Exercise has been considered as an effective strategy to protect against aging-related complications such as sarcopenia. Few studies have shown changes in both fusion and fission-related factors in aging skeletal muscle following endurance training (3). However, the effect of High-Intensity Interval Training (HIIT) on fission factors has not been well elucidated in aging.
Aims: Therefore, the purpose of this study was to research the effect of HIIT on Drp1 and Fis1 gene expression in skeletal muscle of old rats.
Methods: Eight young male Wistar rats with the age of eight to ten weeks and the mean of 320 g in weight, and also 16 old rats with 16 to 18 months of age and mean of 450 g in weight were provided for the research. Young rats were considered as Young-Control (n=8). The old rats were divided into Old-sedentary (n=8) and Old-Training (n=8). The training group was subjected to exercise training on a treadmill with 10° inclination for eight weeks (5 days per week). Rats were exercise-trained by six interval occasions so that they ran at 90% vVo2peak for 3-minutes followed by a 2-minute active recovery at 50% vVo2peak for 2-minutes. The gene expression of Drp1 and Fis1 in the Soleus muscle was determined by Real-Time PCR.
Results: Data showed a higher level in Fis1 gene expression in the Old-Sedentary group as compared to the Young-Control group (3.4-fold; P=0.001). However, Drp1 gene expression was not significantly higher in Old-Sedentary than Young-Control (1.3-fold; P=0.09). Moreover, the expressions of Drp1 and Fis1 were not significantly lower in the Old-Training group as compared to the Old-Sedentary group (P>0.05).
Conclusion: The results imply that the expression levels of the mitochondrial fission-related factor, i.e. Fis1 are increased by aging. However, exercise training as HIIT could not effectively decrease the elevated levels of Fis1 in old rats.
Keywords
Mitochondria Fission, High-Intensity Interval Training, Dynamin-related protein 1, Fission protein 1, aging
Status: Abstract Accepted (Poster Presentation)