The Effect of 4 Weeks of High Intensity Training on Gene Expression of MST1 and MAFbx in EDL Muscle of Aged Mice

The aim of this study was to evaluate the effect of high intensity interval training on gene expressions of MST1andMAFbxin EDL muscles of aged C57bl/6 mice. 28 C57bl/6 mice (14 aged and 14 adults) were assigned to two groups of training and control. After one week of familiarization, training groups participated in 4 weeks of high intensity training program. 48 hours after the last training session, the mice were sacrificed, their EDL muscles were extracted. Then, gene expressions of MST1andMAFbxwere measured with Real Time PCR technique. The results showed that aging significantly increased gene expressions of MST1 andMAFbx(P=0.001 and P=0.028 respectively). On the other hand, 4 weeks of high intensity interval training significantly reduced MST1 gene expression (P≤0.05) and insignificantly reduced MAFbx(P≥0.05) in aged mice. Furthermore, decrease of these two genes in adult group was not significant. Also, a significant decrease was observed in EDL muscle weight in aged mice (P=0.032) although high intensity interval training could slow down the atrophy in the aged. In addition, aging and training had an interactive effect (P=0.001) but this interactive effect of these two factors was not observed on MAFbx (P=0.185). Thus, aging is associated with an increase in MST1 andMAFbx geneexpressions which could be possibly involved in muscle mass changes associated with aging. Since high intensity interval training decreases these gene expressions, it can be used to maintain muscle mass in the aged.