title: MiR-214 promotes the alcohol-induced oxidative stress via down-regulation of glutathione reductase and cytochrome P450 oxidoreductase in liver cells.
abstract: BACKGROUND
  The involvement of oxidative stress in the pathophysiological process of alcohol-induced liver injury has been studied for decades. However, the role of microRNAs (miRNAs) targeting to oxidative stress genes in the pathogenesis of alcohol-induced liver injury has not yet been determined. The aim of this study was to identify the targeting of miR-214 to both glutathione reductase (GSR) and cytochrome P450 oxidoreductase (POR) genes and elucidate their impact on alcohol-induced oxidative stress in liver cells.
  
  
  METHODS
  The miR-214 expression vector and reporter vectors of GSR and POR 3'-UTR were constructed. Human hepatoma cell (Bel7402), human embryonic kidney 293 cell (HEK293), and rat normal hepatocyte (BRL) were transfected and stimulated with ethanol (EtOH). Wistar rats were fed with EtOH for 4 weeks. The GSR and POR protein levels were detected by Western blot, and their activities were measured using the spectrophotometric method. The miR-214 expression was detected by real-time PCR. The index of oxidative stress including the total antioxidant capacity (T-AOC) and malondialdehyde (MDA) level was detected by commercial kits.
  
  
  RESULTS
  miR-214 bound specifically to the GSR and POR 3'-UTR and repressed the expressions and activities of both GSR and POR. EtOH up-regulated the miR-214 expression, down-regulated the GSR and POR protein levels and activities, and induced the oxidative stress in human and rat liver cells. EtOH-fed Wistar rats further confirmed that alcohol up-regulates the miR-214 expression in liver and repressed both GSR and POR in vivo.
  
  
  CONCLUSIONS
  These findings demonstrated a new mechanism by which the alcohol repressed the GSR and POR expression via up-regulation of miR-214 and in turn induced oxidative stress in liver cells.
authors.affiliation: Department of Clinical Genetics, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China; Department of Medical Genetics, China Medical University, Shenyang, Liaoning, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Dong
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Fangjie
authors.initials: F
authors.lastname: Chen
authors.forename: Dejun
authors.initials: D
authors.lastname: Li
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D015536:Down-Regulation / Q000187:drug effects / Q000502:physiology; D000431:Ethanol / Q000008:administration & dosage*; D005980:Glutathione Reductase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D057809:HEK293 Cells; D022781:Hepatocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000502:physiology*; D009251:NADPH-Ferrihemoprotein Reductase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: C547397:MIRN214 microRNA, human; D035683:MicroRNAs; D000431:Ethanol; D009251:NADPH-Ferrihemoprotein Reductase; D005980:Glutathione Reductase
keywords: Alcohol; Cytochrome P450 Oxidoreductase; Glutathione Reductase; Oxidative Stress; microRNA-214