title: Effects of the immunosuppressant rapamycin on the expression of human α2(I) collagen and matrix metalloproteinase 1 genes in scleroderma dermal fibroblasts.
abstract: BACKGROUND
  Rapamycin has been shown to exert an anti-fibrotic effect on skin fibrosis in a certain subset of patients with systemic sclerosis (SSc) and in bleomycin-treated animal models.
  
  
  OBJECTIVE
  To investigate the mechanism responsible for the anti-fibrotic effect of rapamycin especially by focusing on human α2(I) collagen (COL1A2) and matrix metalloproteinase 1 (MMP1) genes in normal and systemic sclerosis (SSc) dermal fibroblasts.
  
  
  METHODS
  The expression levels of type I procollagen and MMP1 proteins were analyzed by immunoblotting and the mRNA levels of COL1A2 and MMP1 genes were evaluated by quantitative real-time RT-PCR. The activities of COL1A2 and MMP1 promoters were determined by reporter analysis.
  
  
  RESULTS
  Rapamycin significantly decreased the levels of type I procollagen protein and COL1A2 mRNA, while significantly increasing the levels of MMP1 protein and mRNA in normal dermal fibroblasts. Similar effects of rapamycin were also observed in SSc dermal fibroblasts. Importantly, the inhibitory and stimulatory effects of rapamycin on the mRNA levels of COL1A2 and MMP1 genes, respectively, were significantly greater in SSc dermal fibroblasts than in normal dermal fibroblasts. In SSc dermal fibroblasts, rapamycin affected the expression of COL1A2 gene at the post-transcriptional level. In contrast, rapamycin altered the expression of MMP1 gene at the transcriptional level through the JNK/c-Jun signaling pathway in those cells.
  
  
  CONCLUSIONS
  Rapamycin has a potential to directly regulate the deposition of type I collagen in extracellular matrix through inhibiting type I collagen synthesis and promoting its degradation by MMP1, suggesting that this drug is useful for the treatment of SSc.
authors.affiliation: Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
authors.forename: Zenshiro
authors.initials: Z
authors.lastname: Tamaki
authors.affiliation: Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan. Electronic address: yasano-tky@umin.ac.jp.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Asano
authors.affiliation: Department of Dermatology, Tokyo Kousei-Nenkin Hospital, Tokyo, Japan.
authors.forename: Masahide
authors.initials: M
authors.lastname: Kubo
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ihn
authors.affiliation: Department of Dermatology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Tada
authors.affiliation: Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sugaya
authors.affiliation: Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kadono
authors.affiliation: Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sato
mesh_terms: D002470:Cell Survival; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism*; D004353:Drug Evaluation, Preclinical; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D020781:Matrix Metalloproteinase 1 / Q000235:genetics / Q000378:metabolism*; D012595:Scleroderma, Systemic / Q000188:drug therapy* / Q000378:metabolism; D020123:Sirolimus / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D024042:Collagen Type I; D007166:Immunosuppressive Agents; C522360:MMP1 protein, human; D020781:Matrix Metalloproteinase 1; D020123:Sirolimus
keywords: Matrix metalloproteinase 1; Rapamycin; Systemic sclerosis; Type I collagen