Notch, Numb and Numb-like responses to exercise-induced muscle damage in human skeletal muscle

Exp Physiol. 2022 Aug;107(8):800-806. doi: 10.1113/EP090364. Epub 2022 May 31.

Abstract

New findings: What is the central question of this study? Do Notch, Numb and Numb-like expression change in human skeletal muscle after exercise-induced muscle damage? What are the main finding and its importance? Notch gene expression trends toward an increase in response to an acute bout of exercise-induced muscle damage, while Numb and Numb-like expression does not change. These results suggest that human skeletal muscle response to exercise-induced muscle damage is dynamic and may differ from Drosophila and rodent models. Furthermore, the timing of muscle biopsies, training status and muscle damage protocols should be considered.

Abstract: This investigation examined changes in the gene and protein expression of Notch, Numb and Numb-like (Numbl) in human skeletal muscle after an acute bout of eccentric exercise-induced muscle damage. Twelve recreationally active male subjects participated in this study. These individuals completed seven sets of 10 repetitions of eccentric leg extension at 120% of one-repetition max with 2 min of rest period between sets. Four muscle biopsies of the vastus lateralis were collected: before exercise (Pre), and 3 h, 2 days and 5 days post-muscle damage. Biopsy samples were used to probe Notch, Numb and Numbl utilizing western blot and RT-qPCR techniques. The results were analysed using a one-way repeated-measures ANOVA. Notch1 mRNA expression trended toward a significant increase from Pre to 2 days post-muscle damage from baseline measures (P = 0.087), while Numb (P = 0.804) and Numbl (P = 0.480) expression was unaltered post-muscle damage. There were no significant differences in protein expression post-muscle damage for any of the proteins. These results suggest that exercise-induced muscle damage, via eccentric exercise, slightly elevates Notch1 mRNA expression.

Keywords: eccentric; injury; satellite cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Exercise* / physiology
  • Humans
  • Male
  • Membrane Proteins* / genetics
  • Membrane Proteins* / metabolism
  • Nerve Tissue Proteins* / genetics
  • Nerve Tissue Proteins* / metabolism
  • Quadriceps Muscle / physiology
  • RNA, Messenger / metabolism
  • Receptor, Notch1* / genetics
  • Receptor, Notch1* / metabolism
  • Rest

Substances

  • Membrane Proteins
  • NOTCH1 protein, human
  • Nerve Tissue Proteins
  • NUMB protein, human
  • RNA, Messenger
  • Receptor, Notch1