Effect of resistance training on mTOR and P70S6K Signaling pathway in skeletal muscle of rats

Document Type : original article

Abstract



Introduction: Elucidating cell signaling mechanisms involved in muscle hypertrophy is one of the challenges
of sport biologists. Purpose: The mammalian target of Rapamycin (mTOR) is the most important factor in
this process that regulated through phosphorylated the ribosomal protein S6 kinase of 70 kDa (p70S6K) and
increases protein synthesis in skeletal muscle. The purpose of this study was to determine the effect of
resistance training (RT) on total (TmTOR) and phosphorylated (PmTOR) mTOR protein content and total
(TP70) and phosphorylated p70s6k (PhP70) protein content, as markers of hypertrophy regulation in flexor
hallucis longus (FHL) in normal male rats undergoing RT. For this purpose, 12 male Sprague Dawley rats
were randomly divided into control (6 = n) and RT (6 = n). The RT consisted of climbing a ladder carrying a
load suspended from the tail for 8 weeks (5 session week). The load of training was progressively changed 30-
200 % of subject's bodyweight. To investigate muscle samples, 48 hour after the last training session, FHL
muscle was removed while animals were anestheitized. TmTOR, PmTOR, TP70PC and PhP70PC was
measured by ELISA in muscle extract. One-way ANNOVA was used. Results:The results showed RT muscle
had a significantly greater Pour and p70s6k (P=0.001) (P=0.04).but no significant difference in TmTOR and
p70s6k (p=0.421) (p=0.94). Totally, these Conclusion: findings, demonstrate that RT causes hypertrophy
with increased phosphorylation of mTOR and p70s6k fitted.

Keywords

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Journal of Sport and Exercise Physiology
Volume 8, Issue 1 - Serial Number 15
February 2016
Pages 1149-1156

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History

  • Receive Date: 09 February 2016
  • Revise Date: 11 June 2024
  • Accept Date: 31 December 2020
  • First Publish Date: 31 December 2020
  • Publish Date: 21 April 2015

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