Alteration in cell morphology triggers transforming growth factor-beta 1, collagenase, and tissue inhibitor of metalloproteinases-I expression in normal and hypertrophic scar fibroblasts

J Invest Dermatol. 1995 Jan;104(1):118-23. doi: 10.1111/1523-1747.ep12613609.

Abstract

Using immunocytochemistry and Northern blot analysis, we investigated the role of cell morphology and reorganization of the cytoskeleton in the expression of transforming growth factor-beta 1 (TGF-beta 1) in human dermal fibroblasts. Disruption of the cytoskeleton was induced by three different agents--trypsin, ethyl-eneglycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), or cytochalasin--and was confirmed by staining with rhodamine-labeled phalloidin. Immunocytochemical staining with antibodies specific for TGF-beta 1 revealed a cell-shape-related induction of TGF-beta 1. Northern blot analysis of total RNA showed a significant increase in the expression of TGF-beta 1 mRNA as early as 4 h and peaking at 12 h after disruption of the cytoskeleton. Quantitative analysis of TGF-beta 1 mRNA expression at 4 h after treatment with trypsin, EGTA, or cytochalasin C showed increases of 2.6-, 3.3-, and 2.6-fold, respectively. Disruption of the cytoskeleton by trypsin, EGTA, or cytochalasin C increased mRNA for collagenase by 3.8-fold, 2.3-fold, or 2.5-fold, respectively. The expression of mRNA for tissue inhibitor of metalloproteinases I (TIMP-I) also showed a 3.2-fold increase by trypsin, a 3.6-fold increase by EGTA, and a 2.5-fold increase by cytochalasin C. Cell-shape-related induction of TGF-beta 1, collagenase, and TIMP-I genes appears to be selective, as the levels of mRNA for fibronectin and type I procollagen were not significantly altered. These data suggest that gene expression of TGF-beta 1, collagenase, and TIMP-I is governed by the status of the cytoskeleton microfilament organization, which may be a mechanism of gene regulation during cell division, migration, and differentiation, events fundamental to wound healing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / chemistry
  • Blotting, Northern
  • Cicatrix / pathology*
  • Cicatrix / physiopathology
  • Collagenases / genetics
  • Collagenases / physiology
  • Cytoskeleton / pathology
  • Fibroblasts / chemistry
  • Fibroblasts / cytology*
  • Glycoproteins / genetics
  • Glycoproteins / physiology*
  • Humans
  • Hypertrophy / metabolism
  • Immunohistochemistry
  • Matrix Metalloproteinase Inhibitors
  • RNA, Messenger / analysis
  • Staining and Labeling
  • Tissue Inhibitor of Metalloproteinases
  • Transforming Growth Factor beta / genetics
  • Transforming Growth Factor beta / physiology*

Substances

  • Actins
  • Glycoproteins
  • Matrix Metalloproteinase Inhibitors
  • RNA, Messenger
  • Tissue Inhibitor of Metalloproteinases
  • Transforming Growth Factor beta
  • Collagenases