title: Epimorphin alters the inhibitory effects of SOX9 on Mmp13 in activated hepatic stellate cells.
abstract: OBJECTIVE
  Liver fibrosis is a major cause of morbidity and mortality. It is characterised by excessive extracellular matrix (ECM) deposition from activated hepatic stellate cells (HSCs). Although potentially reversible, treatment remains limited. Understanding how ECM influences the pathogenesis of the disease may provide insight into novel therapeutic targets for the disease. The extracellular protein Epimorphin (EPIM) has been implicated in tissue repair mechanisms in several tissues, partially, through its ability to manipulate proteases. In this study, we have identified that EPIM modulates the ECM environment produced by activated hepatic stellate cells (HSCs), in part, through down-regulation of pro-fibrotic Sex-determining region Y-box 9 (SOX9).
  
  
  METHODS
  Influence of EPIM on ECM was investigated in cultured primary rat HSCs. Activated HSCs were treated with recombinant EPIM or SOX9 siRNA. Core fibrotic factors were evaluated by immunoblotting, qPCR and chromatin immunoprecipitation (ChIP).
  
  
  RESULTS
  During HSC activation EPIM became significantly decreased in contrast to pro-fibrotic markers SOX9, Collagen type 1 (COL1), and α-Smooth muscle actin (α-SMA). Treatment of activated HSCs with recombinant EPIM caused a reduction in α-SMA, SOX9, COL1 and Osteopontin (OPN), while increasing expression of the collagenase matrix metalloproteinase 13 (MMP13). Sox9 abrogation in activated HSCs increased EPIM and MMP13 expression.
  
  
  CONCLUSIONS
  These data provide evidence for EPIM and SOX9 functioning by mutual negative feedback to regulate attributes of the quiescent or activated state of HSCs. Further understanding of EPIM's role may lead to opportunities to modulate SOX9 as a therapeutic avenue for liver fibrosis.
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: James
authors: J
authors: Pritchett
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: Varinder S
authors: VS
authors: Athwal
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom.
authors: Emma
authors: E
authors: Harvey
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: Katherine
authors: K
authors: Martin
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: Jessica
authors: J
authors: Llewellyn
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom.
authors: Philip
authors: P
authors: Ireland
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom.
authors: Alexander
authors: A
authors: Nicolaides
authors: Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester, United Kingdom.
authors: Martin J
authors: MJ
authors: Humphries
authors: School of Dentistry, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom.
authors: Nicoletta
authors: N
authors: Bobola
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: Neil A
authors: NA
authors: Hanley
authors: Centre for Endocrinology and Diabetes, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom; Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom.
authors: Karen
authors: K
authors: Piper Hanley
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D003094:Collagen / Q000378:metabolism; D004195:Disease Models, Animal; D015870:Gene Expression; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D055166:Hepatic Stellate Cells / Q000378:metabolism*; D008103:Liver Cirrhosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D053509:Matrix Metalloproteinase 13 / Q000235:genetics / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D059372:Nucleotide Motifs; D010447:Peptide Hydrolases / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D059748:Proteolysis; D051381:Rats; D055758:SOX9 Transcription Factor / Q000235:genetics / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D055758:SOX9 Transcription Factor; C504581:Stx2 protein, rat; D003094:Collagen; D010447:Peptide Hydrolases; D053509:Matrix Metalloproteinase 13