Comparison of the Alterations of Gene Expression Related to Signaling Pathways of Synthesis and Degradation of Skeletal Muscle Protein Induced by Two Exercise Training Protocols

Background and Objectives: Skeletal muscle mass depends on the balance between synthesis and degradation of muscle protein, which changes with aging and disease. The aim of the present reserch was to examine the effects of two exercise training protocols on alterations of some genes involved in pathways of protein synthesis and degradation in order to achieve a more effective training program in case of pathological conditions, aging process, and improvement of athletic performance. Methods: In this experimental study, 8 week old Wistar rats, were randomly divided into three groups of resistance training, high-intensity interval training, and control. To examine gene expression, 48 hours after the last exercise session, the Soleus muscles were dissected and stored at -80C. Between-group differences, were analysed using parametric and non-parametric tests at the significance level of α˂0.05. Results: Compared to the control group, the increased expression of AKT and Rps6kb1 genes, was significant in both training groups (especially resistance group). Moreover, the gene expression related to the protein degradation signaling pathway, (MuRF1 and Map1LC3a), were suppressed by both training protocols, especially high-intensity interval training group and were confirmed by Western blotting analysis. Conclusion: Given the fact that the protein synthesis-related gene expression was increased by resistance training and protein degradation-related gene expression was suppressed by high-intensity interval training, the practical application of the two protocols can be considered simultaneously in order to reduce muscle atrophy in pathological conditions, aging, as well as to increase muscle strength to improve athletic performance