title: Fibrinogen production is enhanced in an in-vitro model of non-alcoholic fatty liver disease: an isolated risk factor for cardiovascular events?
abstract: BACKGROUND
  Cardiovascular disease (CVD) remains the major cause of excess mortality in patients with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to investigate the individual contribution of NAFLD to CVD risk factors in the absence of pathogenic influences from other comorbidities often found in NAFLD patients, by using an established in-vitro model of hepatic steatosis.
  
  
  METHODS
  Histopathological events in non-alcoholic fatty liver disease were recapitulated by focused metabolic nutrient overload of hepatoblastoma C3A cells, using oleate-treated-cells and untreated controls for comparison. Microarray and proteomic data from cell culture experiments were integrated into a custom-built systems biology database and proteogenomics analysis performed. Candidate genes with significant dysregulation and concomitant changes in protein abundance were identified and STRING association and enrichment analysis performed to identify putative pathogenic pathways.
  
  
  RESULTS
  The search strategy yielded 3 candidate genes that were specifically and significantly up-regulated in nutrient-overloaded cells compared to untreated controls: fibrinogen alpha chain (2.2 fold), fibrinogen beta chain (2.3 fold) and fibrinogen gamma chain (2.1 fold) (all rank products pfp <0.05). Fibrinogen alpha and gamma chain also demonstrated significant concomitant increases in protein abundance (3.8-fold and 2.0-fold, respectively, p <0.05).
  
  
  CONCLUSIONS
  In-vitro modelling of NAFLD and reactive oxygen species formation in nutrient overloaded C3A cells, in the absence of pathogenic influences from other comorbidities, suggests that NAFLD is an isolated determinant of CVD. Nutrient overload-induced up-regulation of all three fibrinogen component subunits of the coagulation cascade provides a possible mechanism to explain the excess CVD mortality observed in NAFLD patients.
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. N.W.Yeung@sms.ed.ac.uk.
authors.forename: Emily N W
authors.initials: EN
authors.lastname: Yeung
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. p.treskes@ed.ac.uk.
authors.forename: Philipp
authors.initials: P
authors.lastname: Treskes
authors.affiliation: Kinetic Parameter Facility, SynthSys, Centre for Synthetic and Systems Biology, University of Edinburgh, C.H. Waddington Building, The Kings Buildings, Edinburgh, EH9 3JD, UK. smartoak@gmail.com.
authors.forename: Sarah F
authors.initials: SF
authors.lastname: Martin
authors.affiliation: Bioinformatics Team, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK. jonathan.manning@ed.ac.uk.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Manning
authors.affiliation: Bioinformatics Team, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK. donald.dunbar@sistemic.co.uk.
authors.forename: Donald R
authors.initials: DR
authors.lastname: Dunbar
authors.affiliation: Kinetic Parameter Facility, SynthSys, Centre for Synthetic and Systems Biology, University of Edinburgh, C.H. Waddington Building, The Kings Buildings, Edinburgh, EH9 3JD, UK. sophie_rogers@hotmail.co.uk.
authors.forename: Sophie M
authors.initials: SM
authors.lastname: Rogers
authors.affiliation: Kinetic Parameter Facility, SynthSys, Centre for Synthetic and Systems Biology, University of Edinburgh, C.H. Waddington Building, The Kings Buildings, Edinburgh, EH9 3JD, UK. thierry.lebihan@ed.ac.uk.
authors.forename: Thierry
authors.initials: T
authors.lastname: Le Bihan
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. Ann.Lockman@nhslothian.scot.nhs.uk.
authors.forename: K Ann
authors.initials: KA
authors.lastname: Lockman
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. steve.morley@ed.ac.uk.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Morley
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. P.Hayes@ed.ac.uk.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Hayes
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. L.Nelson@ed.ac.uk.
authors.forename: Leonard J
authors.initials: LJ
authors.lastname: Nelson
authors.affiliation: Hepatology Laboratory, Division of Health Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK. j.plevris@ed.ac.uk.
authors.forename: John N
authors.initials: JN
authors.lastname: Plevris
mesh_terms: D002318:Cardiovascular Diseases / Q000209:etiology*; D045744:Cell Line, Tumor; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000378:metabolism; D005340:Fibrinogen / Q000096:biosynthesis*; D056726:Genetic Association Studies; D006801:Humans; D008954:Models, Biological; D065626:Non-alcoholic Fatty Liver Disease / Q000150:complications / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D040901:Proteomics; D012307:Risk Factors; D015398:Signal Transduction; D015854:Up-Regulation
chemical_list: D005340:Fibrinogen; D013186:Farnesyl-Diphosphate Farnesyltransferase