Evaluation of AKT and mTOR Protein Changes in Response to Eccentric and Concentric Physical Activity in Healthy Young Men

Subject Areas : Journal of Animal Biology

Alireza Hemmati Sarapardeh ^{1 *} , Fatemeh Shab Khiz ² , Khosro Ebrahim ³

1 - Department of Sports Physiology, Kish International Campus, University of Tehran, Kish, Iran
2 - Department of Sports Physiology, Faculty of Physical Education and Sport Sciences, University of Tehran, Tehran, Iran
3 - Department of Sports Physiology, Faculty of Physical Education and Sport Sciences, Shahid Beheshti University, Tehran, Iran

Received: 2021-04-14 Accepted : 2021-06-12 Published : 2022-02-20

Keywords: concentric contraction, eccentric contraction, mTOR, AKT,

Abstract :

Skeletal muscle resorption is caused by the biosynthesis of new structures involved in the muscle contraction in terms of the increased skeletal muscle cross-sectional area, which is recognized as one of the major muscle changes as a result of exercise. This study aimed to investigate the response of mTOR and AKT proteins to distinct eccentric and concentric resistance training in healthy subjects. Ten healthy men were randomly divided into two groups (5 patients in the eccentric group - 5 in eccentric group). Isokinetic contraction protocols included eccentric and concentric knee extension with maximum power and angular velocity of 60 degrees per second. The torques assigned to each subject were assumed to match the workload in both protocols, with a rotational speed of 60 degrees per second. Contractions consisted of a maximum of 12 sets of 10 repetitions for the right leg, a rest time of 30 seconds between each set. At the beginning and end of the study, biopsy of the lateral broad muscle tissue was performed. A biopsy was performed in both distal and proximal directions of lateral flat muscle. Tissue analysis using immunocytochemistry was used to assess the expression of mTOR and AKT proteins in each group. A dependent t-test and a covariance test were used to assess the data. For data analysis, SPSS21 and Exell 2013 software were utilized. The findings indicated that after one session of exercise, intra-group increases in mTOR and AKT proteins were significant in both eccentric and concentric groups (p ≤0.05).However, the inter-group changes of mTOR and AKT proteins showed no difference between two groups. In general, the present study showed that a session of eccentric and concentric activity leads to changes in the factors involved in skeletal muscle strength and hypertrophy. Besides, these changes in aggregate eccentric contraction are more than concentric.

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