Double-stranded RNA activates a p38 MAPK-dependent cell survival program in biliary epithelia

Am J Physiol Gastrointest Liver Physiol. 2003 Jun;284(6):G924-32. doi: 10.1152/ajpgi.00355.2002. Epub 2003 Jan 22.

Abstract

Double-stranded RNA (dsRNA) is produced during replicative viral infection or genotoxic stress. Thus knowledge of the cellular response to dsRNA is necessary to understand the effects of DNA damage or viral infection in biliary epithelia. We assessed the effect of dsRNA on biliary epithelial cell proliferation and apoptosis and the role of the stress-activated p38 MAPK signaling pathway in these responses. dsRNA did not induce apoptosis or proliferation in Mz-ChA-1 human malignant cholangiocytes, but decreased cytotoxicity induced by camptothecin or tumor necrosis factor-related apoptosis inducing ligand and decreased activity of caspases 3, 8, and 9. Furthermore, dsRNA increased p38 MAPK and JNK kinase active site phosphorylation but had no effect on either MAPK kinase (MEK)1/2 or protein kinase R phosphorylation. Inhibition of p38 MAPK with SB-203580 increased basal caspase activity. Thus dsRNA stimulates a p38 MAPK-dependent cell-survival pathway in biliary epithelial cells that may modulate the response of the biliary epithelia to dsRNA produced during genotoxic injury or virus infection.

MeSH terms

  • Apoptosis
  • Bile Duct Neoplasms / enzymology
  • Bile Duct Neoplasms / metabolism
  • Bile Duct Neoplasms / pathology
  • Bile Ducts / cytology*
  • Bile Ducts / enzymology*
  • Binding Sites
  • Caspase 3
  • Caspases / metabolism
  • Cell Division
  • Cell Line
  • Cell Survival
  • Epithelial Cells / cytology*
  • Epithelial Cells / enzymology*
  • Humans
  • Mitogen-Activated Protein Kinases / metabolism*
  • RNA, Double-Stranded / metabolism*
  • Signal Transduction
  • p38 Mitogen-Activated Protein Kinases

Substances

  • RNA, Double-Stranded
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • CASP3 protein, human
  • Caspase 3
  • Caspases