Differential contribution of hepatitis C virus NS5A and core proteins to the induction of oxidative and nitrosative stress in human hepatocyte-derived cells

J Hepatol. 2005 Oct;43(4):606-13. doi: 10.1016/j.jhep.2005.04.019.


Background/aims: We aimed to explore the effects of hepatitis C virus (HCV) core and NS5A proteins on reactive oxygen (ROS) and nitrogen species (RNS) formation and on gene expression profile of iNOS in human hepatocyte-derived cells.

Methods: Production of ROS and RNS and nitrotyrosine residues accumulation were determined by flow cytometry and fluorescent microscopy as well as by Western blot, respectively, in NS5A- and core-transfected cells. Northern blot, Western blot, real-time PCR, and luciferase assays were used to assess iNOS gene expression in both transfectants.

Results: Cytokine-activated NS5A- and core-transfected cells induced ROS and RNS production but an earlier and more marked increase was observed in NS5A-expressing cells. Superoxide production was also augmented, showing a similar temporal pattern of appearance in both NS5A- and core-transfected cells. Although both NS5A and core HCV proteins were able to up-regulate iNOS gene expression, accompanied by a nitrotyrosine-containing proteins accumulation, an earlier iNOS overexpression was observed in NS5A-expressing cells, suggesting a different time course of iNOS activation pattern for core and NS5A HCV proteins.

Conclusions: Our results indicate a differential contribution of both HCV proteins to oxidative and nitrosative stress generation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Flow Cytometry
  • Genes, Reporter
  • Hepacivirus / physiology*
  • Hepatocytes / physiology*
  • Hepatocytes / virology*
  • Humans
  • Inflammation
  • Luciferases / analysis
  • Luciferases / genetics
  • Models, Biological
  • Nitrates / metabolism*
  • Nitrogen Compounds
  • Oxidative Stress*
  • Polymerase Chain Reaction
  • Reactive Oxygen Species
  • Transfection
  • Viral Core Proteins / physiology*


  • Nitrates
  • Nitrogen Compounds
  • Reactive Oxygen Species
  • Viral Core Proteins
  • nucleocapsid protein, Hepatitis C virus
  • Luciferases