Affordable Access

Oxidant-induced disruption of intestinal epithelial barrier function: role of protein tyrosine phosphorylation.

Authors
Type
Published Article
Journal
The American journal of physiology
Publication Date
Volume
273
Issue
4 Pt 1
Identifiers
PMID: 9357822
Source
Medline

Abstract

The effect of hydrogen peroxide (H2O2) on intestinal epithelial barrier function was examined in Caco-2 and T84 cell monolayers. H2O2 reduced transepithelial electrical resistance (TER) of Caco-2 and T84 cell monolayers. This decrease in TER was associated with a decrease in dilution potential and an increase in [3H]mannitol permeability, suggesting an H2O2-induced disruption of the paracellular junctional complexes. H2O2 administration also induced tyrosine phosphorylation of several proteins (at the molecular mass ranges of 50-90, 100-130, and 150-180 kDa) in Caco-2 cell monolayers. Phenylarsine oxide and sodium orthovanadate, inhibitors of protein tyrosine phosphatase, decreased TER and increased mannitol permeability and protein tyrosine phosphorylation (PTP). A low concentration of sodium orthovanadate also potentiated the effect of H2O2 on TER, dilution potential, mannitol permeability, and PTP. Pretreatment with genistein (30-300 microM) and tyrphostin (100 microM) inhibited the effect of H2O2 on TER, dilution potential, mannitol permeability, and PTP. These studies show that H2O2 increases the epithelial permeability by disrupting paracellular junctional complexes, most likely by a PTP-dependent mechanism.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments