The role of reactive oxygen species (ROS) in osmotic stress, dextran sulfate sodium (DSS) and cyclic stretch-induced tight junction (TJ) disruption was investigated in Caco-2 cell monolayers in vitro and restraint stress-induced barrier dysfunction in mouse colon in vivo. Live cell imaging showed that osmotic stress, cyclic stretch and DSS triggered rapid production of ROS in Caco-2 cell monolayers, which was blocked by depletion of intracellular Ca2+ by 1,2-bis-(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid. Knockdown of CaV1.3 or TRPV6 channels blocked osmotic stress and DSS-induced ROS production and attenuated TJ disruption and barrier dysfunction. N-Acetyl L-cysteine (NAC) and L-NG-Nitroarginine methyl ester (L-NAME) blocked stress-induced TJ disruption and barrier dysfunction. NAC and L-NAME also blocked stress-induced activation of c-Jun N-terminal kinase (JNK) and c-Src. ROS was colocalized with the mitochondrial marker in stressed cells. Cyclosporin A blocked osmotic stress and DSS-induced ROS production, barrier dysfunction, TJ disruption and JNK activation. Mitochondria-targeted Mito-TEMPO blocked osmotic stress and DSS-induced barrier dysfunction and TJ disruption. Chronic restraint stress in mice resulted in the elevation of intracellular Ca2+, activation of JNK and c-Src, and disruption of TJ in the colonic epithelium. Furthermore, corticosterone administration induced JNK and c-Src activation, TJ disruption and protein thiol oxidation in colonic mucosa. The present study demonstrates that oxidative stress is a common signal in the mechanism of TJ disruption in the intestinal epithelium by different types of cellular stress in vitro and bio behavioral stress in vivo.
|Number of pages||19|
|State||Published - Mar 1 2017|
Bibliographical noteFunding Information:
The present study was supported by the National Institute of Health grants [R01-DK55532, R01-AA12307, CA109298 and CA083639].
© 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology