Direct or indirect regulation of muscle protein synthesis by energy status?

Clin Nutr. 2021 Apr;40(4):1893-1896. doi: 10.1016/j.clnu.2020.07.015. Epub 2020 Jul 31.

Abstract

Muscle protein synthesis (MPS) is a complex and finely-regulated mechanism that plays a key role in muscle homeostasis. Amino acid bioavailability is widely considered a major driver of MPS regulation via mTOR pathway activation. However, recent results suggest that amino acid bioavailability affects cellular energy status. Whatever the tool used to modulate energy status (amino acid depletion or mild mitochondrial uncoupling), a decrease in cellular energy status decreases MPS, without necessarily involving the mTOR pathway. Here we propose that energy status directly regulates one or several energy-consuming step(s) during MPS. This new paradigm modifies our vision of protein metabolism and raises prospects for new advances in therapeutics.

Keywords: ATP; Amino acids; Energy status; Malnutrition; Muscle protein synthesis.

Publication types

  • Review

MeSH terms

  • Energy Metabolism / physiology*
  • Humans
  • Muscle Proteins / metabolism*
  • Protein Biosynthesis / physiology*

Substances

  • Muscle Proteins