title: Monocyte chemoattractant protein-1 enhances gene expression and synthesis of matrix metalloproteinase-1 in human fibroblasts by an autocrine IL-1 alpha loop.
abstract: Monocyte chemoattractant protein-1 (MCP-1), a member of the C-C chemokine superfamily, has recently been shown to be involved in the pathogenesis of tissue fibrosis. In vitro studies demonstrated that MCP-1 up-regulates type I collagen gene expression via endogenous production of TGF-beta in rat lung fibroblasts. We here show that recombinant human MCP-1 affects gene expression of interstitial collagenase (matrix metalloproteinase-1 (MMP-1)) in primary human skin fibroblasts and a stable fibroblast cell line. MMP-1 mRNA was induced by MCP-1 (10 ng/ml) as early as 6 h and reached a maximal expression at 24 h. MCP-1 also caused an increase of MMP-2 mRNA expression in both types of fibroblasts at 48 h. Interestingly, tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA was also up-regulated by MCP-1, and TIMP-1 mRNA expression peaked at 48 h in both types of fibroblasts. Immunoblot analysis demonstrated increased levels of MMP-1 and TIMP-1 protein in the culture supernatants of primary fibroblasts stimulated with MCP-1. In addition, MCP-1 strongly induced IL-1 alpha mRNA expression in dermal fibroblasts in parallel with the induction of MMP-1. Preincubation with IL-1 receptor antagonist almost completely abrogated the expression of MMP-1 mRNA, and partially inhibited MMP-1 synthesis induced by MCP-1. Transient transfection of primary skin fibroblasts with a MMP-1 promoter-reporter construct indicated a dose-dependent increase in promoter activity by MCP-1 stimulation. These data demonstrate that MCP-1 up-regulates MMP-1 mRNA expression and synthesis in human skin fibroblasts at a transcriptional level and provide evidence that this is mediated by an IL-1 alpha autocrine loop.
authors.affiliation: Department of Dermatology, University of Cologne, Germany. yamamoto.derm@med.tmd.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: B
authors.initials: B
authors.lastname: Eckes
authors.forename: C
authors.initials: C
authors.lastname: Mauch
authors.forename: K
authors.initials: K
authors.lastname: Hartmann
authors.forename: T
authors.initials: T
authors.lastname: Krieg
mesh_terms: D019898:Autocrine Communication / Q000276:immunology*; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017077:Culture Media, Conditioned / Q000737:chemistry; D005347:Fibroblasts / Q000201:enzymology* / Q000276:immunology* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D007375:Interleukin-1 / Q000502:physiology*; D020781:Matrix Metalloproteinase 1 / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification; D015533:Transcriptional Activation / Q000276:immunology; D015854:Up-Regulation / Q000276:immunology
chemical_list: D018932:Chemokine CCL2; D017077:Culture Media, Conditioned; D007375:Interleukin-1; D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D020778:Matrix Metalloproteinase 2; D020781:Matrix Metalloproteinase 1