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Background: Gastric intestinal metaplasia is a common pathological feature in patients with Helicobacter pylori (H. pylori) infection. Rabeprazole was widely used as the first-line regimen for H. pylori infectious treatment. The objective of this study is to explore the mechanism of rabeprazole in gastric intestinal metaplasia treatment. Methods: Real-time PCR, Western blotting (WB) and ROS analysis were conducted to confirm that rabeprazole could induce ferroptosis to suppress gastric intestinal metaplasia. Cellular fraction, luciferase and chromatin immunoprecipitation (ChIP) were used to identify the mechanism underlying rabeprazole modulated ferroptosis. Results: Herein, we found rabeprazole treatment led to inhibit CDX2 and MUC2 expression, alleviating gastric intestinal metaplasia, which was attributed to enhanced ferroptosis characterized by decreased GPX4 expression. Inhibition of ferroptosis by ferrostatin-1 (Fer-1) could reverse decreased CDX2 and MUC2 expression caused by rabeprazole. Mechanically, Rabeprazole could inhibit CREB phosphorylation and nuclear translocation, which further decreased the binding of CREB to GPX4 promoter, reducing GPX4 transactivity. Moreover, endogenous PKA interacted with CREB, and this interaction was drastically destroyed in response to rabeprazole treatment. Most importantly, enhanced ferroptosis was observed in H. pylori- infected gastric intestinal metaplasia in comparison to HC control. Conclusion: These findings suggested that rabeprazole induced ferroptosis to reduce CDX2 expression in gastric epithelial cells through PKA/CREB cascade signaling, implying that targeting ferroptosis could be a promising strategy in improving gastric intestinal metaplasia during H. pylori -infected patients. [ABSTRACT FROM AUTHOR]

Objective. Microfold cells (M cells) are specific intestinal epithelial cells for monitoring and transcytosis of antigens, microorganisms, and pathogens in the intestine. However, the mechanism for M-cell development remained elusive. Materials and Methods. Real-time polymerase chain reaction, immunofluorescence, and western blotting were performed to analyze the effect of sorbitol-regulated M-cell differentiation in vivo and in vitro, and luciferase and chromatin Immunoprecipitation were used to reveal the mechanism through which sorbitol-modulated M-cell differentiation. Results. Herein, in comparison to the mannitol group (control group), we found that intestinal M-cell development was inhibited in response to sorbitol treatment as evidenced by impaired enteroids accompanying with decreased early differentiation marker Annexin 5, Marcksl1, Spib, sox8, and mature M-cell marker glycoprotein 2 expression, which was attributed to downregulation of receptor activator of nuclear factor kappa-В ligand (RANKL) expression in vivo and in vitro. Mechanically, in the M-cell model, sorbitol stimulation caused a significant upregulation of phosphodiesterase 4 (PDE4) phosphorylation, leading to decreased protein kinase A (PKA)/cAMP-response element binding protein (CREB) activation, which further resulted in CREB retention in cytosolic and attenuated CREB binds to RANKL promoter to inhibit RANKL expression. Interestingly, endogenous PKA interacted with CREB, and this interaction was destroyed by sorbitol stimulation. Most importantly, inhibition of PDE4 by dipyridamole could rescue the inhibitory effect of sorbitol on intestinal enteroids and M-cell differentiation and mature in vivo and in vitro. Conclusion. These findings suggested that sorbitol suppressed intestinal enteroids and M-cell differentiation and matured through PDE4-mediated RANKL expression; targeting to inhibit PDE4 was sufficient to induce M-cell development. [ABSTRACT FROM AUTHOR]

Background: Metabolic reprogramming is a critical event for cell fate and function, making it an attractive target for clinical therapy. The function of metabolic reprogramming in Helicobacter pylori (H. pylori)-infected gastric intestinal metaplasia remained to be identified. Methods: Xanthurenic acid (XA) was measured in gastric cancer cells treated with H. pylori or H. pylori virulence factor, respectively, and qPCR and WB were performed to detect CDX2 and key metabolic enzymes expression. A subcellular fractionation approach, luciferase and ChIP combined with immunofluorescence were applied to reveal the mechanism underlying H. pylori mediated kynurenine pathway in intestinal metaplasia in vivo and in vitro. Results: Herein, we, for the first time, demonstrated that H. pylori contributed to gastric intestinal metaplasia characterized by enhanced Caudal-related homeobox transcription factor-2 (CDX2) and mucin2 (MUC2) expression, which was attributed to activation of kynurenine pathway. H. pylori promoted kynurenine aminotransferase II (KAT2)-mediated kynurenine pathway of tryptophan metabolism, leading to XA production, which further induced CDX2 expression in gastric epithelial cells. Mechanically, H. pylori activated cyclic guanylate adenylate synthase (cGAS)-interferon regulatory factor 3 (IRF3) pathway in gastric epithelial cells, leading to enhance IRF3 nuclear translocation and the binding of IRF3 to KAT2 promoter. Inhibition of KAT2 could significantly reverse the effect of H. pylori on CDX2 expression. Also, the rescue phenomenon was observed in gastric epithelial cells treated with H. pylori after IRF3 inhibition in vitro and in vivo. Most importantly, phospho-IRF3 was confirmed to be a clinical positive relationship with CDX2. Conclusion: These finding suggested H. pylori contributed to gastric intestinal metaplasia through KAT2-mediated kynurenine pathway of tryptophan metabolism via cGAS-IRF3 signaling, targeting the kynurenine pathway could be a promising strategy to prevent gastric intestinal metaplasia caused by H. pylori infection. 2STnY-xvxhAA5nGkWu7hrz Video Abstract [ABSTRACT FROM AUTHOR]

Rabeprazole is a representative of proton pump inhibitors and widely used in anti‐ulcer treatment. However, the effect of Rabeprazole on gut barrier function remains to be identified. In this study, we show that ZO‐1 expression is decreased in patients receiving Rabeprazole by immunofluorescence (IF) analysis. Western blotting (WB) and real‐time PCR (qPCR) results demonstrate that Rabeprazole treatment leads to a significant downregulation of ZO‐1 expression through inhibition of the FOXF1/STAT3 pathway, leading to destroy barrier function, which illustrates a novel pathway that Rabeprazole regulates barrier function in gastric epithelial cells. Mechanistically, Rabeprazole treatment led to a downregulation of STAT3 and FOXF1 phosphorylation, leading to inhibit nuclear translocation and decrease the binding of STAT3 and FOXF1 to ZO‐1 promoter, respectively. Most important, endogenous FOXF1 interacted with STAT3, and this interaction was dramatically abolished by Rabeprazole stimulation. Overexpression of STAT3 and FOXF1 in GES‐1 cells reversed the inhibitory effect of Rabeprazole on ZO‐1 expression, respectively. These finding extended the function of Rabeprazole and established a previously unappreciated mechanism by which the Rabeprazole/FOXF1/STAT3 axis facilitated ZO‐1 expression to regulate barrier function, and a comprehensive consideration and evaluation was required in treatment of patients. [ABSTRACT FROM AUTHOR]

Background. CD147/basigin (Bsg), a transmembrane glycoprotein, activates matrix metalloproteinases and promotes inflammation. Objective. The aim of this study is to explore the clinical significance of CD147 in the pathogenesis of inflammatory bowel disease (IBD). Results. In addition to monocytes, the clinical analysis showed that there is no significance obtained in leucocyte, neutrophil, eosinophil, basophil, and erythrocyte between IBD and controls. Immunohistochemistry analysis showed that CD147 was increased in intestinal tissue of patients with active IBD compared to that in the control group. What is more, CD147 is involved in intestinal barrier function and intestinal inflammation, which was attributed to the fact that it has an influence on MCT4 expression, a regulator of intestinal barrier function and intestinal inflammation, in HT-29 and CaCO2 cells. Most importantly, serum level of CD147 content is higher in active IBD than that in inactive IBD or healthy control, which could be a biomarker of IBD. Conclusion. The data suggested that increased CD147 level could be a biomarker of IBD in children. [ABSTRACT FROM AUTHOR]

CD103 is considered as a surface marker for the resident immune cells. However, little is known about the intrinsic function of CD103 in infection and inflammation. In this study, we found that CD103 was highly expressed in CD4+T cells of the gastric mucosa from patients with H. pylori -positive gastritis. Mucosal resident CD103+CD4+T cells exhibited an increase in the CD45RO+CCR7− effector memory phenotype and high expression of the chemokine receptors CXCR3 and CCR9 compared with those in CD103−CD4+T cells. An In vitro coculture study demonstrated that H. pylori -specific antigen CagA/VacA-primed dendritic cells (DCs) induced proliferation and IFN-γ, TNF as well as IL-17 production by CD103+CD4+T cells from patients with H. pylori -positive gastritis, while blocking CD103 with a neutralizing antibody reduced proliferation and IFN-γ, TNF, and IL-17 production by CD103+CD4+T cells cocultured with DCs. Moreover, immunoprecipitation revealed that CD103 interacted with TCR α/β and CD3ζ, and activation of CD103 enhanced the phosphorylation of ZAP70 induced by the TCR signal. Finally, increased T-bet and Blimp1 levels were also observed in CD103+CD4+T cells, and activating CD103 increased T-bet and Blimp1 expression in CD4+T cells. Our results explored the intrinsic function of CD103 in gastric T cells from patients with H. pylori -positive gastritis, which may provide a therapeutic target for the treatment of gastritis. [ABSTRACT FROM AUTHOR]