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

Abstract

Aim: To investigate the effects of hydrogen-rich saline (HRS) on intestinal epithelial tight junction (TJ) barrier in rats with intestinal ischemia-reperfusion injury (IIRI). Materials and methods: Thirty-two healthy male Sprague-Dawley (SD) rats were randomly divided into four groups (n = 8 each): Sham group, I/R group, HRS group and 4-PBA group. After 45 min of ischemia and 6 h of reperfusion, the rats were sacrificed to collect serum and ileum for detection. Hematoxylin and eosin (H&E) staining was used to observe the morphology of small intestine. The serum expression levels of intestinal fatty acid binding protein (IFABP), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) were determined by enzyme linked immunosorbent assay (ELISA). Imunohistochemistry, immunofluorescence and Western blot were used to detect key proteins in intestinal epithelial TJs, ERS, and ERS-induced apoptosis, including occludin, zonula occludens-1 (ZO-1), glucose-regulated protein 78 (GRP78), X-box binding protein-1 (XBP1), C/EBP-homologous protein (CHOP) and caspase-3. Data was presented as mean ± SEM and compared using one-way ANOVA. A p-value b 0.05 was considered significant. Results: Compared with rats in the I/R group, the Chiu score of ileum damage in the HRS group and 4-PBA group were lower. The levels of serum IFABP, TNF-α, and IL-1β were statistically significant among the groups. Increased expression of TJ proteins occludin and ZO-1 by reducing various parameters of ERS and ERS-induced apoptosis evidenced by down-regulation of the protein levels of GRP78, XBP1, CHOP and caspase-3 were shown in the HRS and 4-PBA groups. Conclusion: HRS had potential protective effects on intestinal barrier in IIRI rats. This study suggested that inhibition of excessive ERS and ERS-induced apoptosis by HRS may reduce intestinal epithelial cells damage and maintain the integrity of intestinal epithelial TJ barrier in rats with IIRI.

Remifentanil Promotes PDIA3 Expression by Activating p38MAPK to Inhibit Intestinal Ischemia/Reperfusion-Induced Oxidative and Endoplasmic Reticulum Stress

“…A growing body of literature has shown that both oxidative and ER stress contribute significantly to epithelial damage during intestinal I/R injury (Bi et al, 2020;Ding et al, 2020;Hartmann et al, 2017;Liu et al, 2019). As a result, oxidative stress in the ER caused by intestinal I/R accelerates the accumulation of unfolded and misfolded proteins, ultimately leading to apoptosis (Jiang et al, 2020;Yin et al, 2020;Yoo et al, 2019). Consistently, in the current study, we found that remifentanil significantly suppressed intestinal I/R-induced oxidative stress, as evidenced by decreased intestinal mucosal MDA and increased intestinal mucosal SOD levels, as well as downregulated ER stress, as evidenced by the decreased mRNA and protein expressions of Bip, CHOP, caspase-12, and cleaved caspase-3 in the intestine.…”

Recombinant angiopoietin-like protein 4 attenuates intestinal barrier structure and function injury after ischemia/reperfusion

“…Recent studies reported that MLC phosphorylation mediated by upregulated MLCK is crucial to intestinal barrier breakdown induced by hypoxia or proinflammatory cytokines[ 7 ]. Tight junctions ZO-1 and CLDN-2 regulated by the MLCK pathway are the two crucial factors regulating the intestinal barrier in I/R[ 5 ].…”

“…Integrity of the intestinal mucosal barrier is retained by the critical factors of tight junctions and intercellular junctions, including transmembrane proteins such as zonula occludens (ZO), claudins (CLDN) and junctional adhesion molecule. These consist of a complex that forms a selectively permeable seal between adjacent epithelial cells, which is a key element in the paradigm of gut-origin MODS[ 5 , 6 ]. Myosin light chain (MLC) phosphorylation via MLC kinase (MLCK) is critical in pathophysiological modulation of intestinal mucosal barrier breakdown.…”

“…Microvascular endothelial cell layer including VE-cadherin (VE-cad) creates a semi-permeable barrier between tissue and blood for the transport of lipids, proteins and electrolytes. Microvascular barrier dysfunction is crucial in the initiation and progression of vascular barrier disruption after I/R[ 5 , 9 , 10 ].…”

Protective effects of molecular hydrogen on lung injury from lung transplantation

“…The activation of ERS caused caspase-12 to translocate from the ER to the cytoplasm, cleaved caspase-9, activated caspase-3, and finally led to apoptosis. HRS has been reported to mitigate ERS and ERS induced apoptosis resulting from I/R in multiple organs including myocardium, 48 intestinal, 49 liver, 50,51 and brain, 52 as revealed by down-regulated mRNA and protein levels of the pivotal proteins involved in ERS, such as glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP). According to the results of research by Sun et al, HRS treatment could alleviate the elevated GRP78, CHOP and X-box binding protein-1mRNA expression induced by hyperoxia exposure, hinting that hydrogen could significantly reduce hyperoxic acute lung injury in rats by inhibiting the elevation in ERS.…”