Role of phospholipase Cgamma-induced activation of protein kinase Cepsilon (PKCepsilon) and PKCbetaI in epidermal growth factor-mediated protection of tight junctions from acetaldehyde in Caco-2 cell monolayers

J Biol Chem. 2008 Feb 8;283(6):3574-3583. doi: 10.1074/jbc.M709141200. Epub 2007 Nov 8.

Abstract

Epidermal growth factor (EGF) protects the intestinal epithelial tight junctions from acetaldehyde-induced insult. The role of phospholipase Cgamma (PLCgamma) and protein kinase C (PKC) isoforms in the mechanism of EGF-mediated protection of tight junction from acetaldehyde was evaluated in Caco-2 cell monolayers. EGF-mediated prevention of acetaldehyde-induced decrease in transepithelial electrical resistance and an increase in inulin permeability, and subcellular redistribution of occludin and ZO-1 was attenuated by reduced expression of PLCgamma1 by short hairpin RNA. EGF induced a rapid activation of PLCgamma1 and PLC-dependent membrane translocation of PKCepsilon and PKCbetaI. Inhibition of PKC activity or selective interference of membrane translocation of PKCepsilon and PKCbetaI by RACK interference peptides attenuated EGF-mediated prevention of acetaldehyde-induced increase in inulin permeability and redistribution of occludin and ZO-1. BAPTA-AM and thapsigargin blocked EGF-induced membrane translocation of PKCbetaI and attenuated EGF-mediated prevention of acetaldehyde-induced disruption of tight junctions. EGF-induced translocation of PKCepsilon and PKCbetaI was associated with organization of F-actin near the perijunctional region. This study shows that PLCgamma-mediated activation of PKCepsilon and PKCbetaI and intracellular calcium is involved in EGF-mediated protection of tight junctions from acetaldehyde-induced insult.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acetaldehyde / chemistry
  • Acetaldehyde / pharmacology*
  • Caco-2 Cells
  • Cell Membrane / metabolism
  • Egtazic Acid / analogs & derivatives
  • Egtazic Acid / pharmacology
  • Epidermal Growth Factor / metabolism*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Membrane Proteins / chemistry
  • Models, Biological
  • Occludin
  • Peptides / chemistry
  • Phospholipase C gamma / metabolism*
  • Protein Kinase C / metabolism*
  • Protein Kinase C beta
  • Protein Kinase C-epsilon / metabolism*
  • Protein Transport
  • Tight Junctions

Substances

  • Membrane Proteins
  • OCLN protein, human
  • Occludin
  • Peptides
  • 1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester
  • Egtazic Acid
  • Epidermal Growth Factor
  • Protein Kinase C
  • Protein Kinase C beta
  • Protein Kinase C-epsilon
  • Phospholipase C gamma
  • Acetaldehyde