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Ulcerative colitis (UC) is a persistent inflammatory intestinal disease that consistently affects the colon and rectum. Its exact cause remains unknown. UC causes a considerable challenge in healthcare, prompting research for novel therapeutic strategies. Although probiotics have gained popularity as possible candidates for managing UC, studies are still ongoing to identify the best probiotics or probiotic mixtures for clinical applications. This study aimed to determine the efficacy of a multi-strain probiotic mixture in mitigating intestinal inflammation in a colitis mouse model induced by dextran sulfate sodium. Specifically, a multi-strain probiotic mixture consisting of Tetragenococcus halophilus and Eubacterium rectale was used to study its impact on colitis symptoms. Anti-inflammatory effects were evaluated using ELISA and flow cytometry. The configuration of gut microbial communities was determined using 16S rRNA metagenomic analysis. According to this study, colitis mice treated with the probiotic mixture experienced reduced weight loss and significantly less colonic shortening compared to untreated mice. Additionally, the treated mice exhibited increased levels of forkhead box P3 (Foxp3) and interleukin 10, along with decreased expression of dendritic cell activation markers, such as CD40+, CD80+, and CD83+, in peripheral blood leukocytes and intraepithelial lymphocytes. Furthermore, there was a significant decrease in the frequencies of CD8+N.K1.1+ cells and CD11b+Ly6G+ cells. In terms of the gut microbiota, probiotic-mixture treatment of colitis mice significantly increased the abundance of the phyla Actinobacteria and Verrucomicrobia (p < 0.05). These results provide valuable insights into the therapeutic promise of multi-strain probiotics, shedding light on their potential to alleviate colitis symptoms. This research contributes to the ongoing exploration of effective probiotic interventions for managing inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Background: Epithelial-mesenchymal transition (EMT) is important in the development of peritoneal fibrosis. Glucose degradation products (GDPs) may induce EMT in human peritoneal mesothelial cells (HPMCs). Methods: The effects of individual GDPs and GDPs derived from peritoneal dialysis fluid (PDF) in both HPMCs and peritoneal membranes were evaluated. EMT was assessed with α-smooth muscle actin (α-SMA) and E-cadherin. Results: In vitro, α-SMA protein and mRNA levels increased in the presence of the GDPs (formaldehyde, glyoxal, methylglyoxal, and 3-deoxyglucosone), and E-cadherin decreased. Changes in the EMT markers were most prominent after exposure to 3-deoxyglucosone. Changes in both α-SMA and E-cadherin protein levels were less with low (L)-GDP bicarbonate/lactate-buffered PDF compared to high (H)-GDP PDF. In the rat model after 8 weeks’ PDF infusion, the α-SMA/E-cadherin mRNA ratio increased in the H-GDP group compared with the L-GDP group (p < 0.05). The peritoneum in the H-GDP group tended to be thicker (p = 0.052) and had more blood vessels than that in the L-GDP group (p < 0.05). Tissue staining for TGF-β1 decreased in the L-GDP group. Dual-stained cytokeratin and α-SMA-positive myofibroblasts in the submesothelial layer were more prominent in the H-GDP group. Conclusion: GDPs found in PDF induce EMT of HPMCs, which is associated with peritoneal fibrosis and vascularization. Conversely, L-GDP PDF reduces EMT and peritoneal fibrosis. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Phenotype transition of mesothelial cells, such as epithelial-to-mesenchymal transition (EMT), is one of the early mechanisms of peritoneal fibrosis, which is mediated by oxidative stress and inflammation. Nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a multiprotein oligomer that promotes the maturation of IL-1β and IL-18. Paricalcitol is reported to exert an anti-inflammatory effect; however, there are no studies as to whether paricalcitol modulates the activation of NLRP3 inflammasome. We investigated the role of NLRP3 inflammasome in peritoneal EMT with an exploration of the effect of paricalcitol on oxidative stress, NLRP3 inflammasome, and EMT of mesothelial cells. TGF-β1-induced EMT in human peritoneal mesothelial cells (HPMCs) was associated with an up-regulation of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and procaspase-1, with an increased production of IL-1β and IL-18, which was ameliorated by small interfering (si)NLRP3, siASC, caspase inhibitors, or neutralizing antibodies for IL-1β and IL-18. TGF-β1 enhanced reactive oxygen species generation with an increase in NADPH oxidase (NOX) activity and mitochondrial NOX4 production. Paricalcitol alleviated TGF-β1-induced EMT and the NLRP3 inflammasome, which was associated with a down-regulation of NOX activity by interfering with p47phox and p22phox interaction and mitochondrial NOX4 production in HPMCs. Taken together, paricalcitol ameliorated EMT of HPMCs via modulating an NOX-dependent increase in the activity of NLRP3 inflammasome. Paricalcitol could be a novel approach to protect the peritoneum from the development of EMT and peritoneal fibrosis.-Ko, J., Kang, H.-J., Kim, D.-A., Ryu, E.-S., Yu, M., Lee, H., Lee, H. K., Ryu, H.-M., Park, S.-H., Kim, Y.-L., Kang, D.-H. Paricalcitol attenuates TGF-β1-induced phenotype transition of human peritoneal mesothelial cells (HPMCs) via modulation of oxidative stress and NLRP3 inflammasome.

Objective: Glucose degradation products (GDPs) are formed during heat sterilization and storage of peritoneal dialysis (PD) fluids. 3,4-dideoxyglucosone-3-ene (3,4-DGE) has been identified as the most bioreactive GDP. 3,4-DGE induces apoptosis in leukocytes and renal tubular epithelial cells. Our aim was to evaluate the apoptotic effects of 3,4-DGE on human peritoneal mesothelial cells (HPMCs)., Methods: Primary cultured HPMCs were treated with 25 or 50 micromol/L 3,4-DGE. MTT assay was used to determine cell viability. Apoptosis was measured using TUNEL assay and flow cytometry. Expressions of procaspase-3, Bax, and Bcl-2 were estimated by Western blot. Activity of caspase-3 was measured and the effect of the caspase inhibitor zVAD-fmk (Z-Val-Ala-DL-Asp-fluoromethylketone) was evaluated by TUNEL assay., Results: 3,4-DGE treatment accelerated cell death in HPMCs in a dose- and time-dependent manner. Treatment with 3,4-DGE (25 and 50 micromol/L) significantly increased apoptosis compared to control (p<0.05 and p<0.01 respectively) by TUNEL assay. Flow cytometry showed treatment with 50 micromol/L 3,4-DGE significantly increased apoptosis compared to control (p<0.05). Decreased expression of procaspase-3 and increased activity of caspase-3 were observed in the presence of 50 micromol/L 3,4-DGE compared to control and 25 micromol/L 3,4-DGE (p<0.05). 3,4-DGE-induced HPMC apoptosis was decreased after pretreatment with the pan-caspase inhibitor zVAD-fmk in the 50 micromol/L 3,4-DGE-treated group (p<0.001). The ratio of Bcl-2 to Bax expression was decreased in the 25 micromol/L and the 50 micromol/L 3,4-DGE-treated groups compared to control (p<0.05)., Conclusions: 3,4-DGE promotes apoptosis in HPMCs by a caspase-related mechanism.

Background: TGF-beta is involved in peritoneal changes during long-term peritoneal dialysis (PD). TGF-beta induces betaig-h3 in several cell lines, and betaig-h3 may be a marker for biologically active TGF-beta. However, no study has reported induction of betaig-h3 in human peritoneal mesothelial cells (HPMCs) or its involvement in PD-related peritoneal membrane changes., Methods: We used cultured HPMCs to investigate the biological roles of betaig-h3 during mesothelial cell injury and repair, employing the adhesion, spreading, scratching and cell migration assays. Changes in betaig-h3 expression after high glucose exposure in vivo were also evaluated using an animal chronic PD model., Results: In vitro, TGF-beta1 induced betaig-h3 in cultured HPMCs, and betaig-h3-mediated mesothelial cell adhesion occurred via alphavbeta3 integrin. betaig-h3 enhanced mesothelial cell adhesion and migration and, in part, wound healing during mesothelial cell injury. The animal study demonstrated that compared to the control group, betaig-h3 concentrations in the dialysate effluent increased in the dialysis group with alterations in peritoneal structure and function during PD, and betaig-h3 positively correlated with peritoneal solute transport. Immunohistochemical and immunoblotting results showed that betaig-h3 localizes in the mesothelium and submesothelial matrix of the parietal peritoneum, and in the vascular endothelium of omentum. betaig-h3 protein expression was higher in the dialysis group., Conclusion: In vitro, betaig-h3 induced by TGF-beta1 in HPMCs improved adhesion and migration of HPMCs during wound healing. In the chronic infusion model of PD, betaig-h3 played a role in the functional deterioration of the peritoneal membrane, which is associated with fibrosis.