Gentianine alleviates dextran sulfate sodium-induced ulcerative colitis via inhibition of TLR4/NLRP3-mediated pyroptosis

Regulation of pyroptosis by natural products in ulcerative colitis: mechanisms and therapeutic potential

Ulcerative colitis (UC), a chronic inflammatory bowel disease, is driven by dysregulated immune responses and persistent intestinal inflammation. Pyroptosis, a caspase/gasdermin-mediated inflammatory cell death that exacerbates mucosal damage through excessive cytokine release and epithelial barrier disruption. Although pyroptosis is considered to be a key mechanism in the pathogenesis of UC, the systematic assessment of the role of natural products in targeting the pyroptosis pathway remains a critical research gap. The purpose of this review is to investigate the regulatory effects of natural products on pyroptosis in UC and elucidate the mechanisms of action and potential therapeutic effects. Key findings highlight polyphenols (e.g., resveratrol), flavonoids (e.g., Quercetin), and terpenoids as promising agents that inhibit NLRP3 inflammasome activation, suppress gasdermin D cleavage, and restore barrier integrity, thereby reducing pro-inflammatory cytokine release in preclinical UC models. Current evidence shows enhanced efficacy and safety when these compounds are combined with standard therapies, but clinical translation requires overcoming three key barriers: limited human trial data, uncharacterized polypharmacology, and suboptimal pharmacokinetics needing formulation refinement. Future research should prioritize standardized animal-to-human translational models, mechanistic studies on synergistic pathways, and rigorous clinical validation to harness the full potential of natural products in pyroptosis-targeted UC therapies.

Isodeoxyelephantopin ameliorates LPS-induced acute peritonitis by inhibiting NLRP3 inflammasome in vitro and in vivo

Isodeoxyelephantopin (IDET), a sesquiterpene lactone compound isolated from the Asteraceae plant Inula helenium, has been demonstrated to possess excellent antimicrobial, antidiabetic, hepatoprotective, wound healing, anti-inflammatory, and anticancer activities. However, the underlying mechanisms of IDET's anti-inflammatory properties remain unclear. In this study, we investigated the anti-inflammatory effects and mechanisms of IDET using both in vitro and in vivo models. Our findings revealed that IDET dose-dependently inhibited the upregulation of inflammatory cytokines (IL-1β, IL-6, TNF-α) and pro-inflammatory chemokines (MCP-1, CCL20) induced by Lipopolysaccharide (LPS). IDET suppressed the activation of cyclooxygenase-2 (COX-2) and the NLRP3 inflammasome. Subsequent mechanistic investigations demonstrated that IDET inhibited the mRNA and protein levels of Txnip, FOXO1, and EFhd2 in THP-1 cells in a time- and concentration-dependent manner. Furthermore, in an LPS-induced acute peritonitis mouse model, IDET effectively ameliorated symptoms, preserved ileal tissue integrity, attenuated immune cell infiltration, and reduced the expression of inflammatory cytokines in mouse serum. Notably, IDET exhibited an improvement in acute peritonitis by inhibiting the activation of NLRP3 inflammasome. Overall, our study highlights the significant anti-inflammatory activity of IDET, providing valuable insights into its therapeutic potential for acute peritonitis.

Protective role of TRPM7 knockdown in ulcerative colitis via blocking NLRP3 inflammasome-mediated pyroptosis

Transient receptor potential melastatin 7 (TRPM7) has been emerged as a potent drug target for immunomodulation with ion conductance and kinase activities. The research is projected to characterize the influences of TRPM7 on the course of ulcerative colitis (UC) and dissect the latent response mechanisms. The in vivo murine model and in vitro cell model of UC were both stimulated by DSS. RT-qPCR and western blotting tested the abundance of TRPM7. Colonic damage was estimated by Hematoxylin-eosin staining, calculation of colon length, measurement of DAI and MPO assay kit. CCK-8 method and TUNEL staining severally ascertained cell activity and apoptosis. ELISA method assayed the inflammatory levels and relevant assay kits determined oxidative stress levels. FITC-dextran flux, immunohistochemistry, TEER as well as western blotting evaluated intestinal barrier function. Immunofluorescence staining and western blotting appraised NLR family pyrin domain containing 3 (NLRP3)-dependent pyroptosis. Depleted TRPM7 retarded inflammation, oxidative damage as well as intestinal barrier damage both in vitro and in vivo. TRPM7 reduction repressed the pyroptosis mediated by NLRP3 inflammasome. NLRP3 agonist nigericin partly abolished the protection elicited by TRPM7 silencing against inflammation, oxidative damage as well as intestinal barrier damage in vitro. Collectively, TRPM7 deletion might possess the therapeutic potential in UC, the working mechanism of which might involve the inactivation of NLRP3-dependent pyroptosis.

The probiotic Lactobacillus plantarum alleviates colitis by modulating gut microflora to activate PPARγ and inhibit MAPKs/NF-κB

PURPOSE

In order to address the global public health concern of colitis, this study was conducted to investigate the beneficial effect of Lactobacillus plantarum LR002 (LR) on the remission of ulcerative colitis (UC) in mice and to explore the possible underlying mechanisms.

METHODS

The effect of LR on UC was analyzed by using dextran sodium sulfate (DSS)-induced UC model in mice (n = 9). To assess the therapeutic effect of LR on UC in mice, the disease activity index (DAI) of mice, histopathological alterations, intestinal epithelial barrier integrity, and intestinal microflora were determined.

RESULTS

The results demonstrated a reduction in the DSS-induced DAI in UC mice. Additionally, it mitigated colon shortening, minimized intestinal tissue damage, and preserved intestinal tight junction proteins (Claudin-3, Occludin, and ZO-1). LR reduced the levels of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and oxidative mediators (MPO, SOD and MDA) in the colon of UC mice, which could also alleviate the imbalance of intestinal flora in UC mice, increase the abundance of Prevotellaceae, and Ligilactobacillus, and decrease the abundance of Bacteroidaceae and Eubacteriumrum. LR can also increase the levels of PPARγ in the nucleus and inhibit the MAPK/NF-ĸB signaling pathway in UC mice. Besides, the reduction of the content of short-chain fatty acid (SCFAs) in the colon of UC mice was relieved.

CONCLUSION

The above results forge a scientific basis for LR as natural anti-inflammatory food to improve the imbalance of inflammatory intestinal flora and promote intestinal health.

Goat Milk Exosomes Ameliorate Ulcerative Colitis in Mice through Modulation of the Intestinal Barrier, Gut Microbiota, and Metabolites

Goat milk is rich in a variety of nutrients that are important for intestinal health and disease prevention. However, the role of exosomes in goat milk remains to be elucidated. This study investigated for the first time the therapeutic efficacy and molecular underlying mechanisms of mature milk exosomes (M-exo) and goat colostrum exosomes (C-exo) on dextran sodium sulfate-induced ulcerative colitis (UC) in mice. The findings demonstrate that M-exo and C-exo significantly improved physiological indices, suppressed the secretion of proinflammatory cytokines, and diminished oxidative stress and apoptosis in UC mice. Moreover, C-exo and M-exo restored the intestinal barrier function, remodeled the gut microbiota, and improved metabolite composition in the feces of colitis mice. In conclusion, goat milk exosomes ameliorate UC in mice, which provides a basis for the development of functional food applications for the prevention and treatment of inflammatory bowel disease.

Qingzhuan dark tea polysaccharides-zinc alleviates dextran sodium sulfate-induced ulcerative colitis

BACKGROUND

Qingzhuan dark tea polysaccharides (QDTP) have been complexed with Zinc (Zn) to form the Qingzhuan dark tea polysaccharides-Zinc (QDTP-Zn) complex. The present study investigated the protective effects of QDTP-Zn on ulcerative colitis (UC) in mice. The UC mouse model was induced using dextran sodium sulfate (DSS), followed by oral administration of QDTP-Zn (0.2 and 0.4 g kg-1 day-1).

RESULTS

QDTP-Zn demonstrated alleviation of UC symptoms in mice, as evidenced by a decrease in disease activity index scores. QDTP-Zn also regulated colon tissue injury by upregulating ZO-1 and occludin protein expression, at the same time as downregulating tumor necrosis factor-α and interleukin-6β levels. Furthermore, QDTP-Zn induced significant alterations in the abundance of bacteroidetes and firmicutes and notably increased levels of short-chain fatty acids (SCFAs), particularly acetic acid, propionic acid, and butyric acid.

CONCLUSION

In summary, QDTP-Zn exhibits therapeutic potential in alleviating enteritis by fortifying the colonic mucosal barrier, mitigating inflammation and modulating intestinal microbiota and SCFAs levels. Thus, QDTP-Zn holds promise as a functional food for both the prevention and treatment of UC. © 2024 Society of Chemical Industry.

Polyphenol Extracts from Ziziphus jujuba Mill. "Junzao" Attenuates Ulcerative Colitis by Inhibiting the NLRP3 and MAPKs Signaling Pathways and Regulating Gut Microbiota Homeostasis in Mice

SCOPE

Polyphenols are the major active substances in red jujube fruit, and their anti-inflammatory and antioxidant activities suggest their potential utility in the prevention of ulcerative colitis (UC).

METHODS AND RESULTS

In this study, the effect of polyphenol extracts from red jujube (Ziziphus jujuba Mill. "Junzao") (PERJ) on the dextron sulfate sodium (DSS)-induced UC mice is investigated. The result shows that PERJ effectively improves clinical symptoms, including food and water intake, the disease activity insex (DAI) and spleen index, and routine blood levels, and alleviates the shortening of the colon, in mice with DSS-induced UC. Meanwhile, PERJ remarkably decreases the expression of proinflammatory factors. Moreover, PERJ repairs intestinal barrier damage by increasing the expression level of mucin 2 and mucin 3, and the result is also confirmed in the histological assessment. Besides, the expression levels of Nod-like receptor family pyrin domain-containing 3 (NLRP3) and mitogen-activated protein kinase cascade (MAPKs) signaling pathway-related proteins are inhibited by the PERJ administration. Finally, 16S rRNA sequencing analyses reveal that PERJ reverses intestinal microbiota dysbiosis by enhancing the abundance of Firmicutes and decreasing that of Proteobacteria and Bacteroidetes.

CONCLUSION

PERJ probably inhibits the development of UC by suppressing the NLRP3 and MAPKs signaling pathways and regulating gut microbiota homeostasis, and can be considered as a potential resource for preventing UC.