Response of mTOR / P70S6K myokines to eccentric and concentric physical activity in healthy young men

Subject Areas : Journal of Animal Biology

Amirhossein Niroumand ¹ , Ardavan Jamialahmadi ² , Hassan Matin Homaei ³

1 - Department of Sport Physiology, Central Tehran branch, Islamic Azad University, Tehran, Iran
2 - Department of Sport Physiology, Central Tehran branch, Islamic Azad University, Tehran, Iran
3 - Department of Sport Physiology, Central Tehran branch, Islamic Azad University, Tehran, Iran

Received: 2020-08-27 Accepted : 2023-12-07 Published : 2024-03-05

Keywords: Eccentric contraction, Concentric contraction, mTOR / P70S6K,

Abstract :

The purpose of this study was to evaluate the response of mTOR/P70S6K myokines to eccentric and concentric physical activity in healthy young men. 10 healthy men were randomly divided into each group (concentric group of 5 people - eccentric group of 5 people). Isokinetic contraction protocols included eccentric and concentric knee extensions with a maximum strength and angular velocity of 60 °/s. The torques set for each subject were considered the same in order to match the load in both protocols and the reciprocating speed was 60 degrees per second. At the beginning and end of the study, a biopsy was performed of lateral extensor muscle tissue. Real Time PCR technique was used to evaluate the expression of mTOR/P70S6K gene. To analyze the data of this study, dependent t-test and analysis of covariance were used at a significance level of 0.05. The results showed that the changes within the mTOR group were significant in the concentric group but not significant in the eccentric group. Also, the intragroup changes of P70S6K in the eccentric and concentric groups were not significant (P≥0.05). Also, intergroup changes showed no difference between the two groups in both variables (P≥0.05). It seems that the lack of significant changes in the desired variables is due to the lack of sufficient training pressure to stimulate the increase of mTOR/P70S6K. And according to the review of the answer, it seems that in the discussion of compatibility, different results are obtained that need to be examined.

 

References:

1. Bodine S.C. 2006. mTOR signaling and the molecular adaptation to resistance exercise. Medicine and Science in Sports and Exercise, 38(11):1950-1957.
2. Brook M.S., Wilkinson D.J., Mitchell W.K., Lund J.N., Szewczyk N.J., Greenhaff P. L., Atherton P.J. 2015. Skeletal muscle hypertrophy adaptations predominate in the early stages of resistance exercise training, matching deuterium oxide-derived measures of muscle protein synthesis and mechanistic target of rapamycin complex 1 signaling. FASEB Journal, 29(11):4485-4496.
3. Ci Y., Shi K., An J., Yang Y., Hui K., Wu P., Xu C. 2014. ROS inhibit autophagy by downregulating ULK1 mediated by the phosphorylation of p53 in selenite-treated NB4 cells. Cell Death and Disease, 5:e1542.
4. Coffey V.G., Hawley J.A. 2007. The molecular bases of training adaptation. Sports Medicine, 37(9):737-763.
5. Dieli-Conwright C.M., Kiwata J.L., Tuzon C. T., Spektor T.M., Sattler F. R., Rice J.C., Schroeder E.T. 2016. Acute response of PGC-1alpha and IGF-1 Isoforms to maximal eccentric exercise in skeletal muscle of postmenopausal women. Journal of Strength and Conditioning Research, 30(4):1161-1170.
6. Fang Y., Siemionow V., Sahgal V., Xiong F., Yue G.H. 2001. Greater movement-related cortical potential during human eccentric versus concentric muscle contractions. Journal of Neurophysiology, 86(4):1764-1772.
7. Goodman C.A., Frey J.W., Mabrey D.M., Jacobs B.L., Lincoln H.C., You J.S., Hornberger T.A. 2011. The role of skeletal muscle mTOR in the regulation of mechanical load‐induced growth. Journal of Physiology, 589(22):5485-5501.
8. Hortobágyi T., Barrier J., Beard D., Braspennincx J., Koens P., Devita P., Lambert J. 1996. Greater initial adaptations to submaximal muscle lengthening than maximal shortening. Journal of Applied Physiology (1985), 81(4):1677-1682.
9. Kay D., St Clair Gibson A., Mitchell M.J., Lambert M.I., Noakes T.D. 2000. Different neuromuscular recruitment patterns during eccentric, concentric and isometric contractions. Journal of Electromyography and Kinesiology, 10(6):425-431.
10. Kwon I., Jang Y., Cho J.Y., Jang Y. C., Lee Y. 2018. Long-term resistance exercise-induced muscular hypertrophy is associated with autophagy modulation in rats. The Journal of Physiological Sciences, 68(3):269-280.
11. Luciano T.F., Marques S.O., Pieri B. L., de Souza D.R., Araujo L.V., Nesi R. T., de Souza C.T. 2017. Responses of skeletal muscle hypertrophy in Wistar rats to different resistance exercise models. Physiological Research, 66(2):317-323.
12. Luo L., Lu A.M., Wang Y., Hong A., Chen Y., Hu J., Qin Z.H. 2013. Chronic resistance training activates autophagy and reduces apoptosis of muscle cells by modulating IGF-1 and its receptors, Akt/mTOR and Akt/FOXO3a signaling in aged rats. Experimental Gerontology, 48(4):427-436.
13. Mayer C., Zhao J., Yuan X., Grummt I. 2004. mTOR-dependent activation of the transcription factor TIF-IA links rRNA synthesis to nutrient availability. Genes and Development, 18(4):423-434.
14. Moore D.R., Phillips S.M., Babraj J.A., Smith K., Rennie M.J. 2005. Myofibrillar and collagen protein synthesis in human skeletal muscle in young men after maximal shortening and lengthening contractions. American Journal of Physiology-Endocrinology and Metabolism, 288(6):E1153-1159.
15. Nemati J. 2015. Effect of resistance training on mTOR and P70S6K Signaling pathway in skeletal muscle of rats. Journal of Sport Physiology and Physical Activity, 8(1):1149-1156.
16. Ogasawara R., Kobayashi K., Tsutaki A., Lee K., Abe T., Fujita S., Ishii N. 2013. mTOR signaling response to resistance exercise is altered by chronic resistance training and detraining in skeletal muscle. Journal of Applied Physiology (1985), 114(7):934-940.
17. Otto A., Patel K. 2010. Signalling and the control of skeletal muscle size. Experimental Cell Research, 316(18):3059-3066.
18. Phillips S.M., Tipton K.D., Aarsland A., Wolf S.E., Wolfe R.R. 1997. Mixed muscle protein synthesis and breakdown after resistance exercise in humans. American Journal of Physiology, 273(1):E99-107.
19. Sherafati Moghadam M., Salesi M., Daryanoosh F., Hemati Nafar M., Fallahi A. 2018. The effect of 4 weeks of high intensity interval training on the content of AKT1, mTOR, P70S6K1 and 4E-BP1 in soleus skeletal muscle of rats with type 2 diabetes: An experimental study. Journal of Rafsanjan University of Medical Sciences, 17(9):843-854.
20. Spangenburg E.E., Le Roith D., Ward C.W., Bodine S.C. 2008. A functional insulin‐like growth factor receptor is not necessary for load‐induced skeletal muscle hypertrophy. Journal of Physiology, 586(1):283-291.
21. Taghizadeh M., Ahmadizad S., Hovanloo F., Akbarinia A. 2013. Hemodynamic changes in response to concentric and eccentric isokinetic contractions and subsequent recovery period. Cardiovascular Nursing Journal, 2(2):48-56.
22. Watson K., Baar K. 2014. mTOR and the health benefits of exercise. Seminars in Cell and Developmental Biology, 36:130-139.