The Effect of High and Low-Intensity Interval Training on TRF1 and TRF2 Gene Expression in Slow and Fast-Twitch Skeletal Muscles of C57BL/6 Mice: An Experimental Study

Background and Objectives: The process of chronic diseases and aging is associated with reduced telomere length. The aim of this study was to investigate the effect of high-intensity interval training (HIIT) and low-intensity interval training (LIIT) on telomere repeat binding factor 1 and 2 (TRF1 and TRF2) in Soleus (SOL) muscle as a slow-twitch (ST) and Extensor Digitorum Longus (EDL) muscle as a fast-twitch (FT) of mice skeletal muscle. Materials and Methods: In this experimental study, the subjects were C57BL/6 mice (n=24) that were randomly divided into four groups of 6 mice: 1-Base control, 2-control, 3-high-intensity interval training (HIIT), and 4-low-intensity interval training (LIIT). The exercise included 5 days a week for 8 weeks. The gene expression of muscle tissues was measured using RT-PCR. The data were evaluated using two-way ANOVA with Tukey’s post hoc test. Results: By comparing ST and FT muscles (p=0.791) and HIIT and LIIT groups (p=0.164) and also the interaction between muscle type and training intensity (p=0.929), there was no significant difference in the expression of TRF1 gene. There was no significant interaction between TRF2 gene expression in ST and FT muscles at different intensities (p=0.868). But the results of Tukey’s post hoc test showed that in terms of TRF2 gene expression, HIIT (p=0.031) and LIIT (p=0.035) groups showed more increase compared to the control group. Conclusion: HIIT and LIIT similarly improved the telomere system in skeletal muscle of both muscle types, and this system was more affected by telomere elongation effect of TRF2. Key words: Interval training, ST and FT skeletal muscles, TRF1, TRF2 Funding: This study was funded by Shahid Chamran University of Ahvaz. Conflict of interest: None declared. Ethical approval: The Ethics Committee of Jundishapur University of Medical Sciences approved the study (EE/98.24.3.26525/scu.ac.ir). How to cite this article: Mostafa Khodadoost, Saead Shakeryan, Sareh Arjmand, Masood Nikbakht. The Effect of High and Low-Intensity Interval Training on TRF1 and TRF2 Gene Expression in Slow and Fast-Twitch Skeletal Muscles of C57BL/6 Mice:  An Experimental Study. J Rafsanjan Univ Med Sci 2022; 21 (1): 49-70. [Farsi]