Exp Mol Med.
1998 Jun;30(2):59-64.
Interferon-gamma upregulates the stromelysin-1 gene expression by human skin
fibroblasts in culture
- Affiliations
-
- 1Department of Dermatology, Keimyung University School of Medicine, Taegu, Korea.
Abstract
- The equilibrium between deposition and degradation of extracellular matrix(ECM)
is essential to normal tissue development and repair of wound or inflammatory
responses. It has recently become apparent that several cytokines and growth
factors are capable of modulating fibroblast proliferation and biosynthetic
activity. To understand the role of these factors in connective tissue
regulation, we examined the effect of interferon-gamma (IFN-gamma) on
stromelysin-1 gene expression in cultured human dermal fibroblasts. The
steady-state levels of stromelysin-1 mRNA were increased in IFN-gamma treated
cultured dermal fibroblasts. In the CAT assay, the stromelysin-1 promoter
activity was increased 2.8-fold compared with untreated control. Therefore
IFN-gamma stimulates the stromelysin-1 promoter activity, resulting in
transcriptional enhancement of gene expression. Transforming growth factor-beta
(TGF-beta) showed the antagonistic action to the effects of IFN-gamma in
cultured dermal fibroblasts. Furthermore, gel mobility shift assays demonstrated
enhanced AP-1 binding activities in nuclear extracts from cells incubated with
IFN-gamma. These data suggest that IFN-gamma is an up-regulator and TGF-beta is
a down regulator on the stromelysin-1 gene expression, respectively, and the
AP-1 binding site may be necessary for gene response.