Interferon-γ upregulates the stromelysin-1 gene expression by human skin fibroblasts in culture

Abstract

A b s t r a c tThe equilibrium between deposition and degradation of extracellular matrix(ECM) is essential to normal tissue developement 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-( I F N -) on stromelysin-1 gene expres-sion in cultured human dermal fibroblasts. The steady-state levels of stromelysin-1 mRNA were increased in IFN-treated cultured dermal fibroblasts. In the CAT assay, the stromelysin-1 promoter activity was increased 2.8-fold compared with untreated control. Therfore IFNstimulates the stromelysin-1 promoter activity, resulting in transcriptional enhance-ment of gene expression. Transforming growth factor-( T G F -) showed the antagonistic action to the effects of IFNin cultured dermal fibroblasts. Furthermore, gel mobility shift assays demonstrated enhanced AP-1 binding activities in nuclear extracts from cells incubated with IFN-. These data suggest that IFNis an up-regulator and TGF-is a down regulator on the stromelysin-1 gene expression, respectively, and the AP-1 binding site may be necessary for gene response.Keywords: stromelysin-1, interferon-γ, AP-1, gene expression IntroductionThe matrix metalloproteinase (MMP)familly, which includes collagenase (MMP-1), gelatinase (MMP-2), stromelysins (MMP-3), matrilysin and metalloelastase, were structurally related zinc-dependent proteolytic enzymes, yet specific activities are divergent (Wo e s s n e r, 1990; McCachren, 1991;Mauviel, 1993). Stromelysin-1 and -2 are closely related, yet distinct from metalloproteinases, and both can degrade many non-collagenous connetive tissue macromolecules such as fibronectin, laminin, elastin, IgG, and proteoglycans (Chin et al,, 1985). Stromelysin-1-producing keratinocytes resided on the basement membrane, whereas stromelysin-2-producing keratinocytes were in contact with the dermal matrix (Saarialho-Kere et al. , 1993). Furthermore, stromelysin-1 expression was prominent in dermal fibroblasts, whereas no signal for stromelysin-2 was observed in any dermal cells (Saarialhokere et al., 1993). Beside participating in normal connective tissue homeostasis, development and remodeling, the proteolytic activity of matrix metalloproteinases contributes significantly to the tissue damage that occurs in chronic inflamatory disease, such as rheumatoid arthritis and osteoarthrtis (Pelletier et al., 1993), as well as tumor invasion (Martrisian, 1990).Metalloproteinases are produced by multiple cell types and typically, their expressions are tightly regulated and limied to periods of active remodelling. The cell typespecific expression of metalloproteinases is regulated by various factors, including cell-matrix interaction, growth factors and cytokines, lipid mediator, tumor promotors, and inflammatory agent such as bacterial lipopolysaccharide ( S a a r i a l h o...

Critical role of the transcription factor AP‐1 for the constitutive and interferon‐induced expression of IFI 16

“…Such transcription factors are poorly characterized and therefore it is of considerable interest that the promoter of IFI 16, an IFN‐inducible gene, can be regulated through an AP‐1 binding site and that IFNγ can induce binding to AP‐1 sites. This finding confirms other reports that have indicated AP‐1 binding complexes may be transcriptional regulators of IFN‐inducible genes [Lee et al, 1998; Kim et al, 2000] and that increases in expression of fos and Jun family members can be observed following IFN treatment [Rubio, 1997; Der et al, 1998]. Furthermore, signal transduction pathways that lead to activation of AP‐1 binding factors are activated following IFNγ treatment [Liu et al, 1994; Sakatsume et al, 1998; Goh et al, 1999].…”

“…Mutation of the IAE rendered the promoter unresponsive to IFNγ treatment, indicating that the AP‐1 site is functional and contributes to IFNγ‐mediated promoter activation. Similar conclusions were reached by those analyzing the regulation of IL‐18 [Kim et al, 2000], and stromelysin‐1 [Lee et al, 1998] promoters. The MAP kinase pathway has been linked to certain biological activities of IFN such as regulation of hematopoiesis, although the molecular mechanisms underlying these effects are unknown [Verma et al, 2002].…”

Mdr2 (Abcb4)-/- mice spontaneously develop severe biliary fibrosis via massive dysregulation of pro- and antifibrogenic genes

“…As described before for fibroblasts [16] and HSC [17], both MMP-3 and -13 mRNAs are regulated in an opposite manner compared to the profibrogenic transcripts. Thus mRNA expression of MMP-2, a protease that is considered pro-fibrogenic due to its ability to degrade basement membrane collagen [18], a structure that can induce quiescence and inhibit migration of HSC/MF [19], was upregulated in the Mdr2-/-mice at week 4, paralleling their peak profibrogenic activation.…”

Induction of MMP-1, MMP-3 and TIMP-1 in normal dermal fibroblasts by chronic venous leg ulcer wound fluid*

“…Most studies show that the inflammatory mediators interleukin (IL)‐1β and tumour necrosis factor‐α (TNF‐α) upregulate MMP‐1 protein in human skin fibroblasts (21, 22) and fibroblasts isolated from other tissues (23–25). Monocyte chemoattractant protein‐1 stimulates the production of MMP‐1 protein in human fibroblasts via IL‐1α(26), basic fibroblast growth factor induces synthesis of proMMP‐1 (22) and interferon‐gamma enhances MMP‐3 gene expression (27). Of these mediators, IL‐1 and TNF‐α protein levels are known to be higher in venous ulcer wound fluid than in acute mastectomy wound fluid (28) and decrease as venous ulcers start to heal (29, 30).…”