Changes in the expression levels of tight junction components during reconstruction of tight junction from mucosal lesion by intestinal ischemia/reperfusion

Abstract

Tight junction (TJ) is composed of the most apical components of the intercellular junctional complex in epithelial cells; TJ has cell polarity and functions as a major determinant of epithelial barrier function. In this study, to clarify the components of TJ required for its reconstruction and functional acquisition, we examined the changes in intestinal mucosal structure that depended on mucosal lesion by intestinal I/R, that is, the changes in mRNA and protein expression of the claudin family and scaffold proteins. We used an in vivo intestinal I/R model made using the spring scale and surgical sutures, and examined the mRNA and protein expression levels of TJ components by real-time RT-PCR and Western blotting, respectively. Changes in mRNA and protein expression levels of TJ components by intestinal I/R were observed. Among them, characteristic changes were observed in claudin-2 and claudin-4. In addition, the expression behavior of multi-PDZ domain protein (MPDP) mRNA was similar to that of claudin-4. In conclusion, in the recovery process of TJ from mucosal lesion by intestinal I/R, it was suggested that claudin-2 and claudin-4 strongly participate in the reconstruction and functional acquisition of TJ, respectively. Furthermore, it was suggested that MPDZ, which is scaffold protein, also has an important role in these processes.

Hydrogen-rich saline protects intestinal epithelial tight junction barrier in rats with intestinal ischemia–reperfusion injury by inhibiting endoplasmic reticulum stress-induced apoptosis pathway

“…Studies have found that the pro-inflammatory cytokines TNF-α and IL-1β play a central role in an increase in intestinal epithelial TJ permeability [26,27]. Loss of tight junction proteins due to IIRI affects intestinal epithelial barrier function [28,29]. The results of this experiment on the TJ proteins prove this point of view.…”

Entamoeba histolytica EhCP112 Dislocates and Degrades Claudin-1 and Claudin-2 at Tight Junctions of the Intestinal Epithelium

“…Trophozoites degraded all proteins tested except claudin-4 and tubulin (Figures 7A,B ), confirming that distinct trophozoites molecules produce dissimilar effect on host cell proteins. Intriguingly, trophozoites degraded occludin; although they did not affect paracellular flux in Caco-2 cells (Figure 3 ), possibly, claudin-4, a molecule that also regulates paracellular flux (Takizawa et al, 2014 ; Khan and Asif, 2015 ) performed a compensatory effect in this function, given that it was not affected by trophozoites.…”

Stem Cell-Based Therapies for Inflammatory Bowel Disease

“…This is consistent with the increased gut TJ disruption observed in IBD patients as well as the barrier defect after the disruption. It is worth mentioning that the TJ is mainly composed of zonula occludens (ZO) proteins, transmembrane proteins (junctional adhesion molecules, occludins, and claudins), and cytoskeletal structures [ 23 ]. In conclusion, the integrity of the intestinal mechanical barrier function can resist the invasion of IBD, and the inflammatory response of IBD can further damage the mechanical barrier function.…”