Increased HGF and c-Met in muscle tissues of polymyositis and dermatomyositis patients: beneficial roles of HGF in muscle regeneration

Clin Immunol. 2010 Sep;136(3):387-99. doi: 10.1016/j.clim.2010.04.015. Epub 2010 May 23.

Abstract

We investigated the expression of hepatocyte growth factor (HGF), which has mitogenic and anti-fibrotic activities, in muscle tissue of polymyositis/dermatomyositis (PM/DM) patients, as well as its functional roles in cultured myoblasts. Immunohistochemistry in muscle from PM/DM patients revealed that HGF was expressed predominantly on infiltrating mononuclear cells and that muscle cells expressed the receptor c-met. Cultured myoblasts produced HGF; which was increased by IL-1alpha but suppressed by TGF-beta and dexamethasone. Exogenous HGF induced myoblast proliferation and reduced procollagen type I production. Furthermore, HGF enhanced the gene expression of muscle regulatory factors MyoD and Myf5, while suppressing expression of fibrosis-related genes, connective tissue growth factor and alpha-smooth muscle actin. Although dexamethasone showed contrasting effects to HGF on the expression of these genes, co-treatment with HGF ameliorated the effects of dexamethasone. Taking the beneficial roles of HGF into consideration, administration of HGF might contribute to muscle regeneration in PM/DM especially under corticosteroid treatment.

MeSH terms

  • Actins / genetics
  • CD56 Antigen / metabolism
  • Case-Control Studies
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Collagen Type I / biosynthesis
  • Connective Tissue Growth Factor / genetics
  • Dermatomyositis / metabolism*
  • Dexamethasone / pharmacology
  • Gene Expression / drug effects
  • Hepatocyte Growth Factor / metabolism*
  • Hepatocyte Growth Factor / pharmacology
  • Humans
  • Immunohistochemistry
  • MyoD Protein / genetics
  • Myoblasts, Skeletal / cytology
  • Myoblasts, Skeletal / drug effects
  • Myoblasts, Skeletal / metabolism
  • Myogenic Regulatory Factor 5 / genetics
  • Polymyositis / metabolism*
  • Proto-Oncogene Proteins / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptor Protein-Tyrosine Kinases / metabolism*
  • Recombinant Proteins / pharmacology
  • Regeneration / drug effects
  • Regeneration / genetics
  • Regeneration / physiology
  • c-Mer Tyrosine Kinase

Substances

  • ACTA2 protein, human
  • Actins
  • CCN2 protein, human
  • CD56 Antigen
  • Collagen Type I
  • HGF protein, human
  • MYF5 protein, human
  • MyoD Protein
  • MyoD1 myogenic differentiation protein
  • Myogenic Regulatory Factor 5
  • Proto-Oncogene Proteins
  • RNA, Messenger
  • Recombinant Proteins
  • Connective Tissue Growth Factor
  • Hepatocyte Growth Factor
  • Dexamethasone
  • MERTK protein, human
  • Receptor Protein-Tyrosine Kinases
  • c-Mer Tyrosine Kinase