English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Hydrogen peroxide (H 2 O 2 ) increases paracellular permeability of Madin-Darby canine kidney (MDCK) cells, but the mechanism mediating this effect remains unclear. Treatment of MDCK cells with H 2 O 2  activated ERK 1/2. Inhibition of ERK 1/2 activation blocked the ability of H 2 O 2  to increase paracellular permeability. Knockdown of zonula occludens-1 (ZO-1) protein but not occludin eliminated the ability of H 2 O 2  to increase paracellular permeability. H 2 O 2  treatment did not, however, affect the total cell content or contents of the Triton X-100-soluble and -insoluble fractions for occludin, ZO-1, or ZO-2. H 2 O 2  treatment decreased the number of F-actin stress fibers in the basal portion of the cells. Similar to wild-type MDCK cells, H 2 O 2  increased ERK 1/2 activation in ZO-1 knockdown and occludin knockdown cells. Inhibition of ERK 1/2 activation blocked the increase in paracellular permeability in occludin knockdown cells. ZO-1 knockdown cell paracellular permeability was regulated by PP1, an src inhibitor, indicating that the loss of response to H 2 O 2  was not a general loss of the ability to regulate the paracellular barrier. Inhibition of myosin ATPase activity with blebbistatin increased paracellular permeability in ZO-1 knockdown cells but not in wild-type MDCK cells. H 2 O 2  treatment sensitized wild-type MDCK cells to inhibition of myosin ATPase. Knockdown of TOCA-1 protein, which promotes formation of local branched actin networks, reproduced the effects of ZO-1 protein knockdown. These results demonstrate that H 2 O 2  increases MDCK cell paracellular permeability through activation of ERK 1/2. This H 2 O 2  action requires ZO-1 protein and TOCA-1 protein, suggesting involvement of the actin cytoskeleton.

ZO-1 protein is required for hydrogen peroxide to increase MDCK cell paracellular permeability in an ERK 1/2-dependent manner