Wnt7a induces satellite cell expansion, myofiber hyperplasia and hypertrophy in rat craniofacial muscle

Sci Rep. 2018 Jul 13;8(1):10613. doi: 10.1038/s41598-018-28917-6.

Abstract

Craniofacial muscles drive critical functions in the head, including speech, feeding and expression. Compared with their counterparts in trunk and limbs, craniofacial muscles are of distinct embryonic origins, which might consequently lead to different growth patterns and regenerative potential. In this study, rat levator veli palatini muscle and masseter muscle were compared with tibialis anterior muscle in their response to exogenous Wnt7a stimulus, which has been proved effective in promoting muscle regeneration in the limbs. Histological, cellular and molecular analyses were performed both under basal condition and after a single dose injection of recombinant human Wnt7a. Under basal condition, levator veli palatini muscle demonstrated considerably more satellite cells than the others. After Wnt7a administration, regeneration-related activities, including satellite cell expansion, myofiber hyperplasia and hypertrophy were generally observed in all three muscles, but with obvious differences in the extent. The composition of fast/slow myofibers underwent substantial alterations, and the pattern varied among the three muscles. Location-specific alterations in the expression level of core components in planar cell polarity pathway, Akt/mTOR pathway and myostatin pathway were also observed. In conclusion, both craniofacial and limb muscles could be effectively expanded by exogenous Wnt7a stimulus, but muscle-to-muscle variations in response patterns existed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation / drug effects
  • Facial Muscles / cytology
  • Facial Muscles / drug effects*
  • Facial Muscles / physiology
  • Hyperplasia / chemically induced
  • Hypertrophy / chemically induced
  • Male
  • Muscle Fibers, Skeletal / cytology
  • Muscle Fibers, Skeletal / drug effects*
  • Muscle Fibers, Skeletal / physiology
  • Myostatin / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Recombinant Proteins / administration & dosage
  • Regeneration / drug effects*
  • Satellite Cells, Skeletal Muscle / drug effects*
  • Satellite Cells, Skeletal Muscle / physiology
  • Signal Transduction / drug effects
  • TOR Serine-Threonine Kinases / metabolism
  • Wnt Proteins / administration & dosage*

Substances

  • Mstn protein, rat
  • Myostatin
  • Recombinant Proteins
  • WNT7A protein, human
  • Wnt Proteins
  • mTOR protein, rat
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases