title: Protective role of HO-1 and carbon monoxide in ethanol-induced hepatocyte cell death and liver injury in mice.
abstract: OBJECTIVE
  Alcoholic liver disease is associated with inflammation and cell death. Heme oxygenase-1 (HO-1) is a stress-inducible enzyme with anti-apoptotic and anti-inflammatory properties. Here we tested the hypothesis that induction of HO-1 or treatment with a carbon monoxide releasing molecule (CORM) during chronic ethanol exposure protects and/or reverses ethanol-induced liver injury.
  
  
  METHODS
  Female C57BL/6J mice were allowed free access to a complete liquid diet containing ethanol or to pair-fed control diets for 25days. Mice were treated with cobalt protoporphyrin (CoPP) to induce HO-1 expression during ethanol feeding or once liver injury had been established. Mice were also treated with CORM-A1, a CO-releasing molecule (CORM), after ethanol-induced liver injury was established. The impact of HO-1 induction on ethanol-induced cell death was investigated in primary cultures of hepatocytes.
  
  
  RESULTS
  Induction of HO-1 during or after ethanol feeding, as well as treatment with CORM-A1, ameliorated ethanol-induced increases in AST and expression of mRNAs for inflammatory cytokines. Treatment with CoPP or CORM-A1 also reduced hepatocyte cell death, indicated by decreased accumulation of CK18 cleavage products and reduced RIP3 expression in hepatocytes. Exposure of primary hepatocyte cultures to ethanol increased their sensitivity to TNFα-induced cell death; this response was attenuated by necrostatin-1, an inhibitor of necroptosis, but not by caspase inhibitors. Induction of HO-1 with CoPP or CORM-3 treatment normalized the sensitivity of hepatocytes to TNFα-induced cell death after ethanol exposure.
  
  
  CONCLUSIONS
  Therapeutic strategies to increase HO-1 and/or modulate CO availability ameliorated chronic ethanol-induced liver injury in mice, at least in part by decreasing hepatocellular death.
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Bakytzhan
authors.initials: B
authors.lastname: Bakhautdin
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Dola
authors.initials: D
authors.lastname: Das
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Palash
authors.initials: P
authors.lastname: Mandal
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Sanjoy
authors.initials: S
authors.lastname: Roychowdhury
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Jazmine
authors.initials: J
authors.lastname: Danner
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Katelyn
authors.initials: K
authors.lastname: Bush
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Katherine
authors.initials: K
authors.lastname: Pollard
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: James W
authors.initials: JW
authors.lastname: Kaspar
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH, United States.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Salomon
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Megan R
authors.initials: MR
authors.lastname: McMullen
authors.affiliation: Center for Liver Disease Research, Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States; Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, OH, United States. Electronic address: nagyL3@ccf.org.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Nagy
mesh_terms: D000410:Alanine Transaminase / Q000378:metabolism; D000818:Animals; D001219:Aspartate Aminotransferases / Q000378:metabolism; D001880:Boranes / Q000494:pharmacology; D002248:Carbon Monoxide / Q000378:metabolism*; D002254:Carbonates / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D056486:Chemical and Drug Induced Liver Injury / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D000431:Ethanol / Q000633:toxicity*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D051547:Heme Oxygenase-1 / Q000096:biosynthesis / Q000378:metabolism*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D011524:Protoporphyrins / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D001880:Boranes; D002254:Carbonates; D016207:Cytokines; D008565:Membrane Proteins; D011524:Protoporphyrins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C503854:sodium boranocarbonate; D000431:Ethanol; C007095:cobaltiprotoporphyrin; D002248:Carbon Monoxide; D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase
keywords: Alcoholic liver disease; Apoptosis; Heme oxygenase-1; Hepatocytes; Necroptosis