Acute dietary protein intake restriction is associated with changes in myostatin expression after a single bout of resistance exercise in healthy young men

J Nutr. 2014 Feb;144(2):137-45. doi: 10.3945/jn.113.183996. Epub 2013 Dec 4.

Abstract

Skeletal muscle satellite cells (SCs) play an important role in the myogenic adaptive response to exercise. It remains to be established whether nutrition plays a role in SC activation in response to exercise. In the present study, we assessed whether dietary protein alters the SC response to a single bout of resistance exercise. Twenty healthy young (aged 21 ± 2 y) males were randomly assigned to consume a 4-d controlled diet that provided either 1.2 g protein ⋅ kg body weight(-1) ⋅ d(-1) [normal protein diet (NPD)] or 0.1 g protein ⋅ kg body weight(-1) ⋅ d(-1) [low protein diet (LPD)]. On the second day of the controlled diet, participants performed a single bout of resistance exercise. Muscle biopsies from the vastus lateralis were collected before and after 12, 24, 48, and 72 h of post-exercise recovery. SC content and activation status were determined using immunohistochemistry. Protein and mRNA expression were determined using Western blotting and reverse transcription polymerase chain reaction. The number of myostatin + SCs decreased significantly at 12, 24, and 48 h (range, -14 to -49%; P < 0.05) after exercise cessation, with no differences between groups. Although the number of myostatin + SCs returned to baseline in the type II fibers on the NPD after 72 h of recovery, the number remained low on the LPD. At the 48 and 72 h time points, myostatin protein expression was elevated (86 ± 26% and 88 ± 29%, respectively) on the NPD (P < 0.05), whereas it was reduced at 72 h (-36 ± 12% compared with baseline) in the LPD group (P < 0.05). This study demonstrates that dietary protein intake does not modulate the post-exercise increase in SC content but modifies myostatin expression in skeletal muscle tissue. This trial was registered at clinicaltrials.gov as NCT01220037.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adaptation, Physiological
  • Adult
  • Dietary Proteins / administration & dosage
  • Dietary Proteins / pharmacology*
  • Energy Intake*
  • Exercise / physiology*
  • Humans
  • Male
  • Muscle Fibers, Skeletal / drug effects
  • Muscle Fibers, Skeletal / metabolism
  • Muscle, Skeletal / cytology
  • Muscle, Skeletal / drug effects*
  • Muscle, Skeletal / metabolism
  • Myostatin / metabolism*
  • RNA, Messenger / metabolism
  • Reference Values
  • Resistance Training*
  • Rest / physiology
  • Satellite Cells, Skeletal Muscle / drug effects*
  • Satellite Cells, Skeletal Muscle / metabolism
  • Young Adult

Substances

  • Dietary Proteins
  • Myostatin
  • RNA, Messenger

Associated data

  • ClinicalTrials.gov/NCT01220037