title: MicroRNA-130b regulates scleroderma fibrosis by targeting peroxisome proliferator-activated receptor γ.
abstract: OBJECTIVE
  To investigate the role of microRNA-130b (miR-130b) in systemic sclerosis (SSc) skin fibrosis and its regulatory effect on peroxisome proliferator-activated receptor γ (PPARγ).
  
  
  METHODS
  miR-130b was identified from microarray analyses in our previous studies. The expression of miR-130b, PPARγ, and fibrosis-related genes were determined by real-time PCR analysis. PPARγ protein levels were detected by immunohistochemistry and Western blot. Cells were transfected with microRNA mimics/inhibitor/scramble of miR-130b using Lipofectamine. Luciferase reporter gene assays were used to identify the direct target of miR-130b. Transforming growth factor β (TGF-β) was used for stimulation.
  
  
  RESULTS
  The expression of miR-130b was significantly upregulated and level of PPARγ was decreased in the dermis of the SSc skin biopsy samples and fibroblasts. Similar to human SSc, the same expression patterns of miR-130b, PPARγ, and fibrosis-related genes were observed in the bleomycin-induced skin fibrosis model; TGF-β induced the expression of miR-130b and fibrosis-related genes expression, but downregulated the expression of PPARγ. Overexpression of miR-130b in normal or SSc skin fibroblasts significantly decreased, and accordingly, knockdown of miR-130b increased the levels of PPARγ and fibrosis-related genes. In the reporter gene assay, cotransfection with miR-130b mimics significantly decreased the relative luciferase activity, which suggested a direct regulation of PPARγ by miR-130b.
  
  
  CONCLUSIONS
  These studies demonstrated that miR-130b played important profibrotic roles in SSc fibrosis, and enhanced TGF-β signaling through negative regulation of PPARγ expression. MiR-130b may be a potential therapeutic target in SSc fibrosis.
authors.affiliation: Department of Rheumatology, Xiangya Hospital, Central South University , Changsha, Hunan , P. R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Luo
authors.forename: Honglin
authors.initials: H
authors.lastname: Zhu
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.forename: Xianzhong
authors.initials: X
authors.lastname: Xiao
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Zuo
mesh_terms: D000818:Animals; D001706:Biopsy; D015153:Blotting, Western; D002478:Cells, Cultured; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008811:Mice, Inbred DBA; D035683:MicroRNAs / Q000096:biosynthesis / Q000235:genetics*; D047495:PPAR gamma / Q000096:biosynthesis / Q000235:genetics*; D012313:RNA / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012595:Scleroderma, Systemic / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction
chemical_list: C582652:MIRN130 microRNA, mouse; D035683:MicroRNAs; D047495:PPAR gamma; D012313:RNA
keywords: PPARγ; Scleroderma; TGF-β; miR-130b