title: Reduced heme oxygenase-1 expression in steatotic livers infected with hepatitis C virus.
abstract: Hepatic nonalcoholic fatty liver disease (NAFLD) is known to exacerbate liver injury due to chronic hepatitis C infection. Heme oxygenase-1 (HO-1) is an important protective antioxidative defense enzyme that is known to be induced in response to NAFLD and other liver injuries. The aim of this study was to evaluate HO-1 expression in HCV infected human livers with concomitant NAFLD.
  
  
  METHODS
  We compared levels of HO-1 in NAFLD liver biopsies from patients with or without chronic HCV infection using immunohistochemistry, immunoblots and real time RT-PCR. We also evaluated frozen sections of liver with dihydroethidium (DHE) or dichlorofluorescein (DCF) fluorescence staining to evaluate O(2)(-) and peroxide production respectively.
  
  
  RESULTS
  HO-1 expression was only increased in NAFLD livers without HCV infection, while HCV infected livers showed reduced HO-1 levels, regardless whether NAFLD was present. In uninfected livers with NAFLD, HO-1 expression was primarily localized in hepatocytes containing fat and areas of injury around the central vein. However, both NAFLD with and without concomitant HCV infection showed high levels of O(2)(-) or peroxide production compared to normal human liver control samples.
  
  
  CONCLUSIONS
  These findings support the hypothesis that NAFLD is an important process for hepatocyte oxidative stress and injury in liver diseases. They also suggest that HCV can repress HO-1 induction in vivo even when other inducers of HO-1 are present.
authors.affiliation: Department of Biology & Biotechnology, The Hashemite University, Al-Zarqa', Jordan. maher_abdalla@yahoo.com
authors.forename: Maher Y
authors.initials: MY
authors.lastname: Abdalla
authors.forename: Meleah M
authors.initials: MM
authors.lastname: Mathahs
authors.forename: Iman M
authors.initials: IM
authors.lastname: Ahmad
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D001706:Biopsy; D005234:Fatty Liver / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D051547:Heme Oxygenase-1 / Q000378:metabolism*; D016174:Hepacivirus; D019698:Hepatitis C, Chronic / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D065626:Non-alcoholic Fatty Liver Disease; D018384:Oxidative Stress / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D000975:Antioxidants; D012333:RNA, Messenger; D051547:Heme Oxygenase-1