First Author | Kim JY | Year | 2009 |
Journal | PLoS One | Volume | 4 |
Issue | 2 | Pages | e4561 |
PubMed ID | 19234607 | Mgi Jnum | J:146227 |
Mgi Id | MGI:3837065 | Doi | 10.1371/journal.pone.0004561 |
Citation | Kim JY, et al. (2009) Intestinal epithelial-derived TAK1 signaling is essential for cytoprotection against chemical-induced colitis. PLoS One 4(2):e4561 |
abstractText | BACKGROUND: We have previously reported that intestinal epithelium-specific TAK1 deleted mice exhibit severe inflammation and mortality at postnatal day 1 due to TNF-induced epithelial cell death. Although deletion of TNF receptor 1 (TNFR1) can largely rescue those neonatal phenotypes, mice harboring double deletion of TNF receptor 1 (TNFR1) and intestinal epithelium-specific deletion of TAK1 (TNFR1KO/TAK1(IE)KO) still occasionally show increased inflammation. This indicates that TAK1 is important for TNF-independent regulation of intestinal integrity. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated the TNF-independent role of TAK1 in the intestinal epithelium. Because the inflammatory conditions were sporadically developed in the double mutant TNFR1KO/TAK1(IE)KO mice, we hypothesize that epithelial TAK1 signaling is important for preventing stress-induced barrier dysfunction. To test this hypothesis, the TNFR1KO/TAK1(IE)KO mice were subjected to acute colitis by administration of dextran sulfate sodium (DSS). We found that loss of TAK1 significantly augments DSS-induced experimental colitis. DSS induced weight loss, intestinal damages and inflammatory markers in TNFR1KO/TAK1(IE)KO mice at higher levels compared to the TNFR1KO control mice. Apoptosis was strongly induced and epithelial cell proliferation was decreased in the TAK1-deficient intestinal epithelium upon DSS exposure. These suggest that epithelial-derived TAK1 signaling is important for cytoprotection and repair against injury. Finally, we showed that TAK1 is essential for interleukin 1- and bacterial components-induced expression of cytoprotective factors such as interleukin 6 and cycloxygenase 2. CONCLUSIONS: Homeostatic cytokines and microbes-induced intestinal epithelial TAK1 signaling regulates cytoprotective factors and cell proliferation, which is pivotal for protecting the intestinal epithelium against injury. |