Dextran sodium sulfate colitis murine model: An indispensable tool for advancing our understanding of inflammatory bowel diseases pathogenesis

Acyloxyacyl Hydrolase Prevents Colitis and Colitis-Associated Colorectal Cancer by Inactivating Stimulatory LPS in the Intestine

Ulcerative colitis (UC) is believed to be triggered by a dysregulated inflammatory response to the intestinal microbiota. Acyloxyacyl hydrolase (AOAH) is a unique host lipase that inactivates Gram-negative bacterial lipopolysaccharides (LPS). After finding that AOAH produced in the intestine decreases stimulatory LPS levels in colon contents, we used the dextran sodium sulfate (DSS) model to test the enzyme's ability to prevent colitis in mice. We found that AOAH played a protective role by decreasing colonic inflammation, tissue injury, and barrier permeability. Increasing or decreasing intestinal LPS abundance exacerbated or alleviated colitis, respectively, suggesting that AOAH prevents colitis by reducing stimulatory intestinal LPS levels. AOAH also mitigated colitis-associated colorectal cancer. This highly conserved enzyme may exert its protective effects by preventing LPS-induced injury to the epithelial cell mitochondria that are important for restoring the mucosal epithelial barrier after injury. By decreasing intestinal levels of stimulatory LPS, AOAH prevents colitis and colorectal cancer.

Winnie Mice: A Chronic and Progressive Model of Ulcerative Colitis

Recent trends show a continuous worldwide rise in the incidence of ulcerative colitis (UC), leading to increased interest in its etiology and pathogenesis, which is currently unknown. To gain a better mechanistic understanding of this disease, many mouse models have been developed over the last several years, with variations of dextran sodium sulfate administration representing the most widely employed. The Winnie mouse strain was created through elicited random mutations in Muc2, resulting in a progressive, chronic intestinal inflammation localized to the colon that worsens over time. Moreover, Winnie mice display immunologic and microbiota features that are similar to those that can be found in UC patients. Phenotypically, the presence, albeit rare, of rectal prolapse and other complications impacting quality of life can be observed in Winnie mice, as well as extraintestinal manifestations that are often associated with UC. While Winnie mice are currently less studied compared to other more established models of colitis, much has been discovered in the initial years of its use as a UC-like model. In summary, the use of Winnie mice adds to the growing armamentarium that is required to develop precision-based medicine for its future application in treating complex multifactorial diseases, such as UC.

Activation of notch signaling pathway is a potential mechanism for mucin2 reduction and intestinal mucosal barrier dysfunction in high-altitude hypoxia

High-altitude hypoxia can cause gastrointestinal issues and damage the intestinal mucosal barrier, which is crucial for digestion and nutrient absorption. The Notch signaling pathway affects this barrier's integrity. This study explores the Notch pathway's role in hypoxia-induced intestinal injury. C57BL/6 mice were used to model intestinal mucosal barrier injury through dextran sodium sulfate (DSS) and hypobaric hypoxia (simulating 5000 m altitude for 7 days). Mice were treated with Notch inhibitor Dibenzazepine (DBZ) and Mucin2 (MUC2) activator Prostaglandin E2 (PGE2). We evaluated weight, colon length, histology, Zonula occludens 1 (ZO-1) and Claudin-1 levels, MUC2 and Notch1 staining, serum diamine oxidase (DAO) and D-lactate (D-La), inflammatory markers, and Notch pathway proteins. DSS and hypoxia caused weight loss, colon shortening, ulcers, and inflammation, with fewer goblet cells and lower MUC2 levels. Elevated serum DAO, D-La, and inflammatory markers indicated severe intestinal damage. DBZ treatment post-DSS and hypoxia significantly reduced these symptoms. PGE2 activation of MUC2 also alleviated symptoms and mitigated intestinal damage. Hypoxia worsens DSS-induced mucosal barrier disruption by activating the Notch pathway, shifting stem cell differentiation towards absorptive cells instead of goblet cells, reducing MUC2 secretion, and intensifying damage. Targeting the Notch pathway and enhancing MUC2 expression could effectively treat hypoxia-induced intestinal injury.

Modulation of occludin, NF-κB, p-STAT3, and Th17 response by DJ-X-025 decreases inflammation and ameliorates experimental colitis

SCOPE

Inflammatory bowel disease (IBD) involves a range of immune-mediated disorders marked by systemic and local intestinal inflammation. We synthesized a novel compound DJ-X-025 and uncovered its anti-inflammatory properties using lipopolysaccharide (LPS)-induced RAW 264.7 macrophages in vitro and a dextran sodium sulfate (DSS)-induced model of colitis.

METHODS AND RESULTS

We evaluated the alteration in cell morphology, cytoskeletal proteins, and inflammatory markers of DJ-X-025 treated LPS-stimulated RAW 264.7 macrophages. We administered DJ-X-025 by oral gavage in DSS-induced colitis, examined colon histology, and alterations of immune cells by flow cytometry, and performed molecular studies using RT-qPCR and western blot analysis. DJ-X-025 treatment markedly altered the morphology of LPS-treated RAW 264.7 macrophages from elongated to round shapes, modulated actin and tubulin, and reduced the level of inflammatory markers like TNF-α, IL-1β, IL-6, and iNOS. Further, we observed that DJ-X-025 steered to improve colon length, muscularis mucosa thickness, and colon inflammatory score compared to the DSS group alone. DJ-X-025 effectively inverted the increased population of activated T cells, Th17, and macrophages in lamina propria by DSS treatment, leading to a substantial reduction in the inflammatory response in the colon. Strikingly, DJ-X-025 treatment enhanced the expression of occludin and diminished the expression of NF-κB and phosphorylation of STAT3 in the colon of DSS-treated mice compared to DSS-alone. Additionally, DJ-X-025 induced the expression of Foxp3 in the colon and, reduced systemic inflammatory cytokine/chemokine levels further supporting its immunomodulatory effects. These results suggest that DJ-X-025 is linked to the induction of occludin expression and decreased expression of p-STAT3/NF-κB and Th17 response in the colon, which together suppresses systemic and colon inflammatory cytokines for effective amelioration of experimental colitis.

CONCLUSION

These findings suggest that DJ-X-025 might be a promising therapeutic agent for the treatment of IBD.

Btbd8 deficiency exacerbates bleomycin-induced pulmonary fibrosis in mice by enhancing myofibroblast accumulation and inflammatory responses

BTBD8 contributes to the pathogenesis of inflammatory bowel disease through regulating intestinal barrier integrity and inflammation. However, its role in idiopathic pulmonary fibrosis (IPF) remains unknown. Here we investigated whether BTBD8 plays a role in bleomycin-induced pulmonary fibrosis. Pulmonary fibrosis was induced in wild-type (WT) and Btbd8 knockout (KO) mice by intratracheal instillation of bleomycin. The mice were sacrificed on day 7 or 12. Subsequently, the progression of bleomycin-induced pulmonary fibrosis was assessed. We found that Btbd8 KO mice are more susceptible to bleomycin-induced pulmonary fibrosis, with more severe body weight loss and pulmonary injury, increased collagen deposition and myofibroblast accumulation. We further demonstrated that BTBD8 functions in pulmonary fibroblasts to suppress the conversion of fibroblasts to myofibroblasts. Moreover, Btbd8 deficiency promotes the infiltration of inflammatory cells and the secretion of pro-inflammatory cytokines in IPF mouse model. These results highlight the critical role of BTBD8 in the pathogenesis of bleomycin-induced pulmonary fibrosis in mice, and suggest that BTBD8 may alleviate bleomycin-induced fibrosis by suppressing the differentiation of fibroblasts to myofibroblast, as well as inflammatory responses.

Relationship between purinergic P2X7 receptor and colorectal cancer: Research progress and future prospect

Purinergic P2X7 receptor (P2X7R) is a cellular transmembrane protein. Its activation leads to the release of cytokines, causing the migration and invasion of cancer cells. The expression of P2X7R is associated with tumor inflammation, survival, proliferation, angiogenesis, and metastasis in colorectal cancer (CRC). Evidence suggests that P2X7R expression appears to be epigenetically regulated by DNA methylation and miRNA regulation. With the in-depth study of P2X7R, the application of P2X7R agonists and antagonists has been discussed in the treatment of CRC. This article reviews the relationship between P2X7R and CRC, focusing on the research progress and future prospects of P2X7R in CRC diagnosis and treat-ment.

Exopolysaccharide of Levilactobacillus brevis M-10 Improved Physiological and Biochemical Indicators and Gut Microbiota in DSS-Induced Colitis Mice

Ulcerative colitis (UC) is a typical type of inflammatory bowel disease, which is often recurrent and directly related with colorectal cancer. Therefore, early prevention and treatment for UC is very necessary. Therefore, it is necessary to find efficient substances to treat the UC with less side effects than drugs. Exopolysaccharides (EPSs) are important bioactive constituents of lactic acid bacteria. The study evaluated the effects of EPS1 produced by Levilactobacillus brevis M-10 on UC by determining the weight, the disease activity index (DAI) and the physiological and biochemical indexes. The pathological structures of colon were observed. The gut microbiota and the short-chain fatty acids were analyzed. The results demonstrated high dose (HD) of EPS1 (400 mg/kg-BW) that had the best effects on UC mice. The HD group restored body weight, decreased DAI and alleviated shortening of the length of the colon, recovered liver tissue, declined lipopolysaccharide, and myeloperoxidase. Also the HD group showed that the expression of tight junction proteins increased, IL-10 up-regulated, IL-6, IL-1β, and TNF-α down-regulated, and the gut microbiota dysbiosis balanced. The HD group markedly elevated the relative abundance of Lachnospiraceae_NK4A136_group, Unclassified-Lachnospiraceae, and Unclassified- Muribaculaceae. Acetic acid, propionic acid, and n-butyric acid were significantly increased in the HD group (P < 0.05). The study could provide a theoretical basis and material support for the exploration of safe functional food in alleviating and preventing UC.

Gallic Acid Ameliorated Chronic DSS-Induced Colitis Through Gut Microbiota Modulation, Intestinal Barrier Improvement, and Inflammation

SCOPE

Gallic acid (GA) is recognized for its purported antiinflammatory properties. GA has been demonstrated to prevent and alleviate the symptoms of chronic colitis through the modulation of the gut microbiota, improvement of the intestinal barrier, and reduction of inflammation.

METHODS AND RESULTS

In order to determine the mechanism by which GA exerts its protective effect against chronic colitis, mice were induced by dextran sulfate sodium (DSS). The reduction in the disease activity index by 25% and the decrease in colon tissue damage indicated that 36 days of GA intervention alleviated chronic DSS-induced colitis symptoms. GA was observed to mitigate weight loss by 2.5% and the shortening of colon by 17.3%, and to diminish the expression of pivotal proteins within the TLR4/nuclear factor κB (NF-κB) signaling cascades, consequently lowering the generation of inflammatory cytokines. Furthermore, GA effectively corrected the gut microbiota imbalance, increased the content of short-chain fatty acids (SCFAs), which in turn suppressed inflammation, and enhanced tight junction protein expression, thereby strengthening the intestinal barrier.

CONCLUSION

GA has the capacity to enhance the efficacy of chronic colitis through a multifaceted mechanism, influencing the gut microbiota, intestinal barrier function, and inflammatory processes. The findings highlight the potential of GA as a preventative strategy for chronic colitis.

TXM-CB13 Improves the Intestinal Mucosal Barrier and Alleviates Colitis by Inhibiting the ROS/TXNIP/TRX/NLRP3 and TLR4/MyD88/NF-κB/NLRP3 Pathways

The activation of inflammasomes (NLRP3 and NLRP1) is central to the pathogenesis of inflammatory bowel disease (IBD). Here we examined the protective effects of a thioredoxin-mimetic peptide CB13 (TXM-CB13), known for its antioxidative stress and anti-inflammatory properties. We examined the effects of TXM-CB13 on dextran sulfate sodium (DSS)-induced colitis and lipopolysaccharide (LPS)-induced NLRP3 inflammasome activation in RAW264.7 macrophages. TXM-CB13 appeared to alleviate symptoms of DSS-induced colitis and to significantly suppress the protein and mRNA levels of NLRP3, Mlck, and IL-1β in colonic tissues. Additionally, TXM-CB13 treatment increased the levels of the intestinal barrier proteins Occludin, ZO-1, and NLRP1, as shown through immunohistochemistry and Western blot analysis. In vitro, TXM-CB13 inhibited LPS-induced TLR4 signaling, reducing MyD88 levels and consequently attenuating the activation of the NF-κB pathways, including p-IκB-α/IκB-α and p-NF-κB-p65/NF-κB-p65. This inhibition further reduced the activation of the NLRP3 inflammasome components, NLRP3, ASC, Caspase-1, GSDMD, and IL-1β. In addition, TXM-CB13 prevented the ROS-mediated dissociation of TXNIP from TRX, inhibiting NLRP3 activation. These findings suggest that TXM-CB13 is a potential therapeutic candidate for IBD through its modulation of the TLR4/MyD88/NF-κB/NLRP3 and ROS/TXNIP/TRX/NLRP3 pathways.

Ganoderic Acid Ameliorates Ulcerative Colitis by Improving Intestinal Barrier Function via Gut Microbiota Modulation

Ulcerative colitis (UC) is a chronic and recurrent gastrointestinal disease that affects millions of humans worldwide and imposes a huge social and economic burden. It is necessary to find safe and efficient drugs for preventing and treating UC. The aim of this study was to determine whether ganoderic acid (GA), the main bioactive components of Ganoderma lucidum, has preventive and therapeutic effect on UC in a dextran sulfate sodium (DSS)-induced UC mouse model. Our experimental results showed that GA significantly ameliorated the body weight loss and disease activity index (DAI) of UC mice. GA significantly restored 11% of the colon length and 69% of the spleen index compared to UC mice. GA significantly decreased the intestinal inflammatory response and improved the barrier function of the intestine by upregulating the tight junction proteins Zonula occludens-1 (ZO-1), occludin and claudin-1. A co-housing experiment showed that gut microbiota accounted for the therapeutic activity of GA on UC, which was confirmed by fecal microbiota transplantation from GA-treated mice to the UC mice. Furthermore, 16S rDNA high-throughput sequencing of fecal bacteria showed that GA significantly enriched the abundance of Lactobacillus, Oscillospira, Odoribacter and Ruminococcus, which were positively correlated with colon length. Furthermore, this study found the functional metabolites, including Indole-3-acetaldehyde (IAAld), Glutamine (Gln) and Glutathione (GSH), reduced barrier damage in the Caco-2 cell model. In conclusion, this study suggests that GA could ameliorate UC by improving intestinal barrier function via modulating gut microbiota and associated metabolites.

Network pharmacology and in vivo study: Unraveling the therapeutic mechanisms of Panax ginseng in potentially treating ulcerative colitis

BACKGROUND

Ulcerative colitis (UC), a chronic and challenging condition, necessitates the development of more effective treatments owing to the unsatisfactory efficacy and side effects associated with current medications. Traditional Chinese medicine (TCM), known for its multi-stage and multi-targeted approach, has a long history in treating gastrointestinal diseases and offering a promising alternative UC treatment. Panax ginseng (P. ginseng), a commonly used remedy for UC in TCM, exemplifies this potential, although the specific components and mechanisms through which its therapeutic effects are exerted remain to be fully elucidated, highlighting the need for further research to unlock its full potential as a treatment option.

AIM

To investigate the key constituents and biological pathways through which P. ginseng exerts therapeutic effects on UC.

METHODS

Network pharmacology investigated the UC-alleviating mechanism of P. ginseng, including “active ingredient-target-disease” network analysis, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses. Panaxadiol (PD; active ingredient of P. ginseng) was tested in a mouse model of 3% dextran sulfate sodium-induced UC, with assessments of body weight, Disease Activity Index scores, and colon length. Colitis and intestinal barrier integrity were analyzed via hematoxylin-eosin and Alcian blue and periodic acid-Schiff staining, immunohistochemistry, real time-quantitative PCR, and western blotting.

RESULTS

By integrating and analyzing the targets of P. ginseng and UC, 15 critical hub genes were discovered. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed the mechanisms involved to be linked to MAPK and PI3K-Akt signaling. Among the 10 main active ingredients identified as potentially effective, PD was most abundant and was validated in vivo to mitigate weight loss, reduce Disease Activity Index scores, and prevent colon shortening. PD also reduced inflammation and suppressed expression of pro-inflammatory cytokines and mediators. In addition, PD increased expression of mucin and tight junction proteins. Ultimately, PD counteracted effects of dextran sulfate sodium by inhibiting phosphorylation of NF-кB and MAPK, while increasing phosphorylation of AMPK and expression of NRF2 and NQO1.

CONCLUSION

PD alleviates colitis and aids intestinal barrier repair, partly via modulation of the MAPK/NF-кB and AMPK/NRF2/NQO1 pathways. These findings also suggest new research methods for treatment of UC with TCM.

The intervention of NLRP3 inflammasome inhibitor: oridonin against azoxymethane and dextran sulfate sodium-induced colitis-associated colorectal cancer in male BALB/c mice

Colorectal cancer (CRC) ranks third globally in cancer diagnoses. The dysregulation of the NLRP3 inflammasome is prominently linked to several types of cancers. Oridonin, a principal component of Rabdosia rubescens, exhibits inhibitory activity against NLRP3 and is well-recognized for its diverse pharmacological benefits. However, its role in an animal model of colitis-associated colorectal cancer (CACC) remains unexplored. In the present study, the effectiveness of oridonin was investigated against CACC, developed using azoxymethane (AOM), a tumour initiator, and dextran sulphate sodium (DSS), a tumour promoter, in male BALB/c mice. The two-stage murine model of inflammation-associated cancer was established by administering AOM (10 mg/kg b.w.; i.p., once) followed by DSS (2% w/v) in drinking water (3 cycles, 7 days/cycle). Over a span of 10 weeks, the dose-dependent (2.5, 5, and 10 mg/kg, b.w.; i.p.) effects of oridonin were investigated in BALB/c mice. Oridonin significantly alleviated CACC severity, as evidenced by reduced DAI scores and restored body weight. Moreover, it attenuated surrogate markers of inflammation, including myeloperoxidase, nitrite, plasma LPS, TNF-α, IL-1β, and DNA damage. Histopathological examination revealed diminished tumorigenesis and apoptotic cells, corroborated by reduced Ki-67 and TNF-α, along with increased p53 expression in the colon. Following oridonin treatment, IHC/immunofluorescence analyses demonstrated a significantly reduced expression of the components of NLRP3 inflammasome including NLRP3, ASC-1, and caspase-1. Notably, the high dose of oridonin (10 mg/kg) consistently exhibited significant protective effects against CACC by modulating various molecular targets. Present findings confirmed the potential of oridonin in the protection of colitis-associated colorectal cancer, providing valuable insights into its mechanism of action and clinical significance.

Creeping Fat-Derived Free Fatty Acids Induce Hyperplasia of Intestinal Muscularis Propria Muscle Cells: A Novel Link Between Fat and Intestinal Stricture Formation in Crohn's Disease

BACKGROUND & AIMS

In Crohn's disease, wrapping of mesenteric fat around the bowel wall, so-called "creeping fat," is highly associated with strictures. The strongest contributor to luminal narrowing in strictures is a thickening of the human intestinal muscularis propria (MP). We investigated creeping fat-derived factors and their effect on mechanisms of human intestinal MP smooth muscle cell (HIMC) hyperplasia.

METHODS

Free fatty acids (FFAs) in creeping fat or noncreeping mesenteric fat organ cultures were measured via lipidomic mass spectrometry. Primary HIMCs were exposed to FFAs and cell proliferation was assessed. Intracellular FFA metabolism pathways and reactive oxygen species were functionally evaluated. Muscle thickness was investigated in dextran sodium sulfate colitis with small molecule inhibition of FFA transport and a novel fat deletion mouse model.

RESULTS

Subserosal creeping fat is associated with a markedly thickened MP. Experimental deletion of mesenteric fat (FAT-ATTAC [fat apoptosis through targeted activation of caspase 8] mouse) reduced MP thickness. Human creeping fat-conditioned medium strongly up-regulated HIMC proliferation. Creeping fat released higher amounts of 5 long-chain FFAs, including palmitate. Inhibition of HIMC long-chain FFA metabolism or FFA uptake into mitochondria through carnitine palmitoyltransferase-1 reduced the palmitate-induced HIMC proliferation. Blockade of conversion of palmitate into phospholipids reduced HIMC proliferation. Prophylactic inhibition of carnitine palmitoyltransferase-1 in experimental dextran sodium sulfate colitis did not ameliorate inflammation, but reduced MP thickness.

CONCLUSIONS

Creeping fat-released long-chain FFAs induce a selective proliferative response by HIMC. These results point to creeping fat as a novel contributor to stricture formation in Crohn's disease.

A galacturonic acid-rich polysaccharide from Citrus medica 'fingered' alleviated the dextran sulfate sodium-induced ulcerative colitis

Ulcerative colitis (UC) treatment is often limited by adverse reactions and high recurrence rates, highlighting the need for safer, more effective therapies. Citrus medica 'Fingered' (C. medica), known for its anti-inflammatory properties, remains underexplored, particularly its polysaccharide components. This study investigated the intestinal protective effects of C. medica polysaccharides extracted via hot water (HWE-CP) and characterized a primary fraction's structure. The dextran sulfate sodium -induced UC mouse model was used to evaluate the intestinal protective activity of HWE-CP, and one of the main fractions was characterized using HPGPC, HPAEC, FTIR, TGA, methylation, and NMR. The results indicated HWE-CP alleviated the UC symptoms in mice by reducing weight loss and disease activity, increasing colon length, minimizing intestinal mucosal damage, strengthening the intestinal barrier, lowering inflammatory factor expression, and balancing gut flora. The primary fraction, HWE-CP-2A, had a molecular weight of 38.28 kDa and comprise Rha, Ara, Gal, and GalA with molar rations of 1.57: 4.46: 2.50: 91.47. Its main chain was →[4)-α-D-GalAp-6-O-CH3(1]5 → 3,4)-α-D-GalAp-6-O-CH3, with α-D-GalAp-(1→) linked to the main chain via the C-3 bond. The polymerization degree was around 25. This study provides evidence for the structural with anti-UC relationships of HWE-CP and lays the foundation for the development of its related products.

Abdominal ultrasound stimulation alleviates DSS-induced colitis and behavioral disorders in mice by mediating the microbiota-gut-brain axis balance

Inflammatory bowel disease (IBD) has the potential to induce neuroinflammation, which may increase the risk of developing neurodegenerative disorders. Ultrasound stimulation to the abdomen is a potential treatment for dextran sulfate sodium (DSS)-induced acute colitis. The present study aimed to investigate whether abdominal low-intensity pulsed ultrasound (LIPUS) can alleviate DSS-induced neuroinflammation through the microbiota-gut-brain axis. Male mice were fed DSS to induce ulcerative colitis. LIPUS stimulation was then applied to the abdomen at intensities of 0.5 and 1.0 ​W/cm2. Mouse biological samples were analyzed, and behavior was evaluated. [18F]FEPPA PET/CT imaging was employed to track and quantify inflammation in the abdomen and brain. Changes in the gut microbiota composition were analyzed using 16S rRNA sequencing. Abdominal LIPUS significantly inhibited the DSS-induced inflammatory response, repaired destroyed crypts, and partially preserved the epithelial barrier. [18F]FEPPA accumulation in the colitis-induced neuroinflammation in the abdomen and specific brain regions significantly decreased after LIPUS treatment. LIPUS maintained intestinal integrity by increasing zonula occludens and occludin levels, reduced lipopolysaccharide-binding protein and lipopolysaccharide levels in the serum, and improved behavioral dysfunctions. Moreover, LIPUS, at an intensity of 0.5 ​W/cm2, reshaped the gut microbiota in colitis-induced mice by increasing the relative abundance of the Firmicutes and decreasing the relative abundance of the Bacteroidota. Our findings demonstrated that abdominal LIPUS stimulation has the potential to be a novel therapeutic strategy to improve colitis-induced behavioral disorders through microbiota-gut-brain axis signaling.

Early-life gut inflammation drives sex-dependent shifts in the microbiome-endocrine-brain axis

Despite recent advances in understanding the connection between the gut microbiota and the adult brain, significant knowledge gaps remain regarding how gut inflammation affects brain development. We hypothesized that gut inflammation during early life would negatively affect neurodevelopment by disrupting microbiota communication to the brain. We therefore developed a novel pediatric chemical model of inflammatory bowel disease (IBD), an incurable condition affecting millions of people worldwide. IBD is characterized by chronic intestinal inflammation, and is associated with comorbid symptoms such as anxiety, depression and cognitive impairment. Notably, 25% of patients with IBD are diagnosed during childhood, and the effects of chronic inflammation during this critical developmental period remain poorly understood. This study investigated the effects of early-life gut inflammation induced by DSS (dextran sulfate sodium) on a range of microbiota, endocrine, and behavioral outcomes, focusing on sex-specific impacts. DSS-treated mice exhibited increased intestinal inflammation and altered microbiota membership, which correlated with changes in microbiota-derived circulating metabolites. The majority of behavioral measures were unaffected, with the exception of impaired mate-seeking behaviors in DSS-treated males. DSS-treated males also showed significantly smaller seminal vesicles, lower circulating androgens, and decreased intestinal hormone-activating enzyme activity compared to vehicle controls. In the brain, DSS treatment led to chronic, sex-specific alterations in microglial morphology. These results suggest that early-life gut inflammation causes changes in gut microbiota composition, affecting short-chain fatty acid (SCFA) producers and glucuronidase (GUS) activity, correlating with altered SCFA and androgen levels. The findings highlight the developmental sensitivity to inflammation-induced changes in endocrine signalling and emphasize the long-lasting physiological and microbiome changes associated with juvenile IBD.

Preclinical studies of natural flavonoids in inflammatory bowel disease based on macrophages: a systematic review with meta-analysis and network pharmacology

Flavonoid is a category of bioactive polyphenolic compounds that are extensively distributed in plants with specific pharmacological properties, such as anti-inflammatory and anti-oxidant. Importantly, natural flavonoids have shown the protected function on the dextran sulfate sodium (DSS)-induced colitis in animals and lipopolysaccharides (LPS)-induced inflammatory response in macrophages. The purpose of this systematic review is to explore the efficacy of natural flavonoids in animal models of IBD (inflammatory bowel disease) and potential mechanisms in macrophages by meta-analysis and network pharmacology in preclinical studies. Relevant foundation studies were searched from January 2010 to November 2023 in databases like PubMed, Elsevier ScienceDirect, and Web of Science. Then, OriginPro software was used to extract values from images, and the analysis was performed using Review Manager 5.3. The retrieved data was analyzed according to the fixed-effects model and random-effects model. Subsequently, heterogeneity was evaluated using the I2 statistics. Lastly, network pharmacology was applied to confirm mechanisms of natural flavonoids on IBD. According to the results of meta-analysis, we found the natural flavonoids exhibited powerful therapeutic effects against IBD, which not only reversed colonic shortness (WMD = 1.33, 95% CI (1.07, 1.59), P < 0.00001), but also reduced histological score (SMD =  - 2.66, 95% CI (- 3.77, - 1.95), P < 0.00001) between natural flavonoid treatment groups compared with the experimental IBD model. Furthermore, treatment with natural flavonoids decreased the levels of tumor necrosis factor-α (TNF-α) in macrophages. Mechanistically, our summarized data substantiate that natural flavonoids alleviate LPS-induced M1 macrophage polarization, anti-oxidant, anti-inflammatory, maintain intestinal barrier, and inhibit the activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in macrophages. Moreover, the results of network pharmacology also support this. This systematic review demonstrated the efficiency of natural flavonoids in treating IBD in preclinical research by meta-analysis and network pharmacology, which offered supporting evidence for clinical trial implementation. However, some limitations remain present, such as technique quality shortage, missed reports on account of negative results, failure to count sample size, and the risk of bias.

Dialdehyde starch-epicatechin gallate conjugate alleviates inflammation in lipopolysaccharide-stimulated RAW264.7 cells and dextran sulfate sodium-induced colitis mice

In this study, epicatechin gallate (ECG), a natural anti-inflammatory agent, was conjugated onto dialdehyde starch (DAS) to achieve high physiological stability. The anti-inflammatory effect of DAS-ECG conjugate was evaluated by lipopolysaccharide (LPS)-stimulated RAW264.7 cells and dextran sulfate sodium (DSS)-induced colitis mice models. Results showed that 25-800 μg/mL of DAS-ECG conjugate was non-cytotoxic to RAW264.7 cells. DAS-ECG conjugate effectively inhibited the abnormal morphology, the production of nitric oxide, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β) and reactive oxygen species, and the apoptosis of LPS-stimulated RAW264.7 cells in a dose-dependent manner. DAS-ECG conjugate significantly reduced the disease activity index, thymus atrophy, spleen enlargement, colon shortening and colon damage of DSS-induced colitis mice. Meanwhile, DAS-ECG conjugate remarkably reduced the levels of TNF-α, IL-6, IL-1β and malondialdehyde but increased the levels of superoxide dismutase and glutathione in the colon tissue of DSS-induced colitis mice. Moreover, DAS-ECG conjugate increased the relative abundance of beneficial bacteria (Akkermansia, Candidatus_Saccharimonas, unclassified_f_Muribaculaceae, Alistipes and Parabacteroides), promoted the production of short-chain fatty acids, and decreased the relative abundance of harmful bacterium (norank_f_Ruminococcaceae) in DSS-induced colitis mice. Therefore, DAS-ECG conjugate could be considered as a promising anti-inflammatory agent.

The Effect of the Size of Gold Nanoparticle Contrast Agents on CT Imaging of the Gastrointestinal Tract and Inflammatory Bowel Disease

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD). CT imaging with contrast agents is commonly used for visualizing the gastrointestinal (GI) tract in UC patients. Contrast agents that provide enhanced imaging performance are highly valuable in this field. Recent studies have made significant progress in developing better contrast agents for imaging the gastrointestinal tract using nanoparticles. However, the impact of nanoparticle size on this application remains unexplored. Gold nanoparticles (AuNPs) serve as an ideal model to investigate the effect of nanoparticle size on imaging of the gastrointestinal tract due to their controllable synthesis across a broad size range. In this study, we synthesized AuNPs with core sizes ranging from 5 to 75 nm to examine the effect of the size in this setting. AuNPs were coated with poly(ethylene glycol) (PEG) to enhance stability and biocompatibility. In vitro tests show that gold nanoparticles are cytocompatible with macrophage cells (∼100% cell viability) and remain stable under acidic conditions, with no significant size changes over time. Phantom imaging studies using a clinical CT scanner indicated that there was no effect of nanoparticle size on CT contrast production, as previously demonstrated. In vivo imaging using a mouse model of acute colitis revealed a strong contrast generation throughout the GI tract for all agents tested. For the most part, in vivo contrast was independent of AuNP size, although AuNP outperformed iopamidol (a clinically approved control agent). In addition, differences in attenuation trends were observed between healthy and colitis mice. We also observed almost complete clearance at 24 h of all formulations tested (less than 0.7% ID/g was retained), supporting their value as a model platform for studying nanoparticle behavior in imaging. In conclusion, this study highlights the potential of nanoparticles as effective contrast agents for CT imaging of the gastrointestinal tract (GIT) in the UC. Further systemic research is needed to explore contrast agents that can specifically image disease processes in this disease setting.

A Versatile and Modular Microfluidic System for Dynamic Cell Culture and Cellular Interactions

A versatile and modular microfluidic system for cell co-culture has been developed. Microfluidic chips, each featuring dual compartments separated by a porous membrane, have been fabricated and assembled within the system to facilitate fluidic interconnection and cell-cell communication through the chip assembly. A set of fluidic valves has been successfully integrated to regulate the flow through the chip assembly. The system allows for chip assembly in various arrangements, including in parallel, in series, and complex connections. Individual chips can be interconnected or disconnected within the system at any time. Moreover, the spatial order and orientation of the chips can be adjusted as needed, enabling the study of different cell-cell arrangements and the impact of the presence or absence of specific cell types. The utility of the system has been evaluated by culturing and interconnecting multi-monolayers of intestinal epithelial cells as a model of the complex cellular system. Epithelial monolayers were grown in multiple chips and interconnected in various configurations. The transepithelial electrical resistance and permeability profiles were investigated in detail for these configurations upon treatment of the cells with dextran sulfate sodium. Immune cells were stimulated through the epithelial layers and the expression of inflammatory cytokines was detected. This miniaturized platform offers controlled conditions for co-culturing key cellular components and assessing potential therapeutic agents in a physiologically relevant setting.

Protective Effect and Gut Microbiota Modulation of Grifola frondosa Antioxidant Peptides in Sodium Dextran Sulfate-Induced Ulcerative Colitis Mice

Grifola frondosa antioxidant peptides (GFAP) were prepared through trypsin enzymolysis and characterized. This study conducted a comprehensive assessment of clinical symptoms, colon pathological injuries, levels of inflammatory factors, expression of inflammation-related proteins, and alterations in gut microbiota composition in mice with ulcerative colitis (UC). The findings demonstrated that GFAP effectively mitigated UC, alleviated mucosal damage, and reduced inflammatory infiltration. Specifically, GFAP administration resulted in significant reductions in pro-inflammatory cytokines IL-6, IL-1β, and TNF-α, while enhancing the expression levels of tight junction proteins such as Occludin and ZO-1. Additionally, GFAP treatment led to decreased levels of Toll-like receptor 4 (TLR-4), inducible nitric oxide synthase (iNOS), and TNF-α. Noteworthy, GFAP also influenced the gut microbiota by decreasing the abundance of Proteobacteria and increasing Bacteroidetes and Firmicutes. Moreover, specific bacteria like Bacteroides uniformis and Alistipes exhibited elevated abundances following GFAP treatment. In summary, GFAP exhibited preventive and protective effects against UC in mice by effectively alleviating clinical symptoms and modulating gut microbiota composition.

Gut microbiota: A new key of understanding for Panax notoginseng against multiple disorders and biotransformation

ETHNOPHARMACOLOGICAL RELEVANCE

Panax notoginseng (Burkill) F.H.Chen(P. notoginseng) has been widely used as an herbal medicine for reducing swelling, relieving pain, promoting blood circulation and stopping bleeding, with notable therapeutic effects on obesity, liver diseases, colitis, Alzheimer's disease, chronic kidney disease and other diseases.

AIM OF THE STUDY

This review highlighted the close link and bidirectional effects between P. notoginseng and gut microbiota, with the ultimate aim of providing new insights into the potential mechanisms of pharmacological effects of P. notoginseng in the treatment of different diseases and PNS transformation.

MATERIALS AND METHODS

By means of some reputable databases (PubMed, China National Knowledge Infrastructure (CNKI), Google Scholar, etc.), we screened the published articles related to P. notoginseng from 1998 to 2024, including original research, clinical trials and review on raw materials and chemical constituents of P. notoginseng. Then, we employed the keywords "gut microbiota", "intestinal microbiota", "gut biotransformation" and "intestinal" to exclude the articles that do not in line with our topic. Plant information was obtained from www.worldfloraonline.org using "Panax notoginseng (Burkill) F.H.Chen" as the keyword.

RESULTS

P. notoginseng elevated certain probiotics including Lactobacillus, Bifidobacterium and Akkermansia, while simultaneously reducing pathogenic bacteria such as Prevotellaceae, Enterococcus, Enterobacter and Helicobacter, to fight various diseases. Meanwhile, considering to the low oral bioavailability and degradable properties of Panax notoginseng saponin (PNS), gut microbiota converted it into protopanaxatriol(PPT) and protopanaxadiol(PPD) mainly through deglycosylation reactions to enhance the bioactivity.

CONCLUSION

Increasing evidences suggest that gut microbiota may play a vital role for P. notoginseng exerting on beneficial effects on the prevention and treatment of metabolic disorders, liver diseases, neurological diseases, chronic kidney diseases, vascular diseases, colitis, and other diseases, as well as for biotransformation of P. notoginseng.

Mannuronate Oligosaccharides Ameliorate Experimental Colitis and Secondary Neurological Dysfunction by Manipulating the Gut-Brain Axis

Microbiota dysfunction induces intestinal disorders and neurological diseases. Mannuronate oligosaccharides (MAOS), a kind of alginate oligosaccharide (AOS), specifically exert efficacy in shaping gut microbiota and relieving cognitive impairment. However, the key regulatory factors involved, such as the specific strains and metabolites as well as their regulatory mechanisms, remain unclear at present. This research investigates how MAOS specifically impact the gut-brain axis in vivo and in vitro. The results showed that pretreatment with MAOS significantly ameliorated dextran sodium sulfate (DSS)-induced colitis and secondary nerve injury. This preventive mechanism operates through the regulation of serum DOPC abundance and the gut-brain axis, achieved by inhibiting the TLR4/MyD88/NF-κB pathway. These findings underscore the crucial role of dietary MAOS in the prevention of colitis and neurological disorders, providing a rationale for the application of MAOS in disease prevention and functional food ingredients.

Sodium orthovanadate protects against ulcerative colitis and associated liver damage in mice: insights into modulations of Nrf2/Keap1 and NF-κB pathways

Ulcerative colitis (UC) is a prominent category of disease that is associated with bowel inflammation, it can occur at any period of life and is prevalently rising on a global scale. Dextran sulfate sodium (DSS) has been extensively used to develop colitis due to its ability to mimic human UC, providing consistent and reproducible inflammation, ulceration, and disruption of the epithelial barrier in the colon. Chronic inflammation in the gut can lead to alterations in the gut-liver axis, potentially impacting liver function over time, while direct evidence linking diversion colitis to liver damage is limited. Thus, the present study aims to assess the gut and liver damage against DSS and the possible molecular mechanisms. Forty-seven animals were randomly assigned to six groups. Ulcerative colitis was induced using 2.5% w/v DSS in three alternate cycles, each lasting 7 days, with 1-week remission periods in between. SOV (5 and 10 mg/kg, orally) and the standard drug 5-aminosalicylic acid (100 mg/kg, orally) were administered from the start of the 2nd DSS cycle until the end of the experiment. Biochemical parameters, ELISA, histopathological, and immunohistochemical analyses have been conducted to assess damage in the colon and liver. SOV significantly reduced colitis severity by lowering the DAI score, oxidative stress markers (LPS, IL-1β, MPO, nitrite), and restoring liver biomarkers (SGPT, SGOT). Histopathological findings supported these protective benefits in the liver and gut. Moreover, immunohistochemical analysis showed SOV enhanced the expression of the cytoprotective mediator Nrf2/Keap-1 and reduced the expression of inflammatory mediators NF-κB and IL-6. Present findings concluded that SOV demonstrated a dose-dependent effect against UC through anti-inflammatory and antioxidant pathways, with the highest dose of SOV 10 mg/kg having more significant (p < 0.001) results than the low dose of 5 mg/kg.

Dextran sodium sulfate-induced colitis alters the proportion and composition of replicating gut bacteria

The bacteria living in the human gut are essential for host health. Though the composition and metabolism of these bacteria are well described in both healthy hosts and those with intestinal disease, less is known about the metabolic activity of the gut bacteria prior to, and during, disease development-especially regarding gut bacterial replication. Here, we use a recently developed single-cell technique alongside existing metagenomics-based tools to identify, track, and quantify replicating gut bacteria both ex vivo and in situ in the dextran sodium sulfate (DSS) mouse model of colitis. We show that the proportion of replicating gut bacteria decreases when mice have the highest levels of inflammation and returns to baseline levels as mice begin recovering. In addition, we report significant alterations in the composition of the replicating gut bacterial community ex vivo during colitis development. On the taxa level, we observe significant changes in the abundance of taxa such as the mucus-degrading Akkermansia and the poorly described Erysipelatoclostridium genus. We further demonstrate that many taxa exhibit variable replication rates in situ during colitis, including Akkermansia muciniphila. Lastly, we show that colitis development is positively correlated with increases in the presence and abundance of bacteria in situ which are predicted to be fast replicators. This could suggest that taxa with the potential to replicate quickly may have an advantage during intestinal inflammation. These data support the need for additional research using activity-based approaches to further characterize the gut bacterial response to intestinal inflammation and its consequences for both the host and the gut microbial community.IMPORTANCEIt is well known that the bacteria living inside the gut are important for human health. Indeed, the type of bacteria that are present and their metabolism are different in healthy people versus those with intestinal disease. However, less is known about how these gut bacteria are replicating, especially as someone begins to develop intestinal disease. This is particularly important as it is thought that metabolically active gut bacteria may be more relevant to health. Here, we begin to address this gap using several complementary approaches to characterize the replicating gut bacteria in a mouse model of intestinal inflammation. We reveal which gut bacteria are replicating, and how quickly, as mice develop and recover from inflammation. This work can serve as a model for future research to identify how actively growing gut bacteria may be impacting health, or why these particular bacteria tend to thrive during intestinal inflammation.

Studies on the alleviating effect of Bifidobacterium lactis V9 on dextran sodium sulfate-induced colitis in mice

Background

Inflammatory bowel disease (IBD) has become a global public health problem with complex pathogenesis and limited therapeutic options. We aimed to investigate the potential mechanisms by which Bifidobacterium lactis V9 (V9) alleviated colitis in a dextran sodium sulfate-induced colitis model mice.

Methods

Mice were induced to develop colitis by drinking DSS solution to induce colitis. The expression of the relevant factors in the blood supernatant of the mice was determined by ELISA. RT-qPCR and Western blotting were used to detect mRNA and protein expression of target genes. The fecal microbiota was analyzed by 16S rRNA sequencing. Intestinal metabolites were analyzed by untargeted metabolomics.

Results

V9 effectively improved the overall symptoms of the colitis model mice. H&E showed that V9 re-stored the intestinal tissue structure. ELISA showed that V9 decreased the levels of IL-6, IL-22, and TNF-α and increased IL-10, SP, VIP, and 5-HT. V9 increased the expression of AHR, CYP1A1, MUC2, Claudin-3, Occludin, and ZO-1, and decreased 5-hydroxytryptamine transporter and Claudin-2. V9 increased the abundance of gut microbiota in colitis mice to promote the growth of beneficial bacteria. V9 increased tryptophan metabolites, and short-chain fatty acids, and improved gut inflammation.

Conclusion

V9 attenuates intestinal inflammation, improves the mucosal barrier, modulates intestinal microecology and exerts a protective effect in a mouse model of DSS-induced colitis.

Akkermansia muciniphila relieves inflammatory response in DSS-induced ulcerative colitis in mice through regulating macrophage polarization via SCFAs-SLC52A2/FFAR2 pathway

Ulcerative colitis (UC) remains an intractable and relapsing disease featured by intestinal inflammation. The anti-UC activity of Akkermansia muciniphila (AKK), an intestinal microorganism, has been widely investigated. The current work is to explore the impacts of AKK on UC and its possible reaction mechanism. In vivo UC model was induced by dextran sulfate sodium (DSS) and phorbol-12-myristate-13-acetate (PMA)-induced THP-1-M0 and raw264.7 macrophages were treated by lipopolysaccharide (LPS). H&E staining evaluated tissue damage. Inflammatory and oxidative stress levels were assessed by relevant kits. The high-throughput analysis of fatty acids was performed by the LC/MS method. RT-qPCR and Western blot detected related gene expression. Flow cytometry measured cell apoptosis and macrophage polarization. Energy metabolism was detected by ELISA, related assay kits, JC-1 staining, and Western blot. AKK reduced the pathological damage of mice colon tissues, alleviated oxidative stress and inflammatory response, upregulated the expression of Occludin-1 and SCFAs receptors, and stimulated M1 to M2 macrophage polarization in vivo. After FFAR2 was silenced, the promoting role of AKK in the viability and M1 to M2 macrophage polarization and the inhibitory role in oxidative stress, inflammation, apoptosis, energy metabolism disorder, necroptosis, and pyroptosis were both reverted. Conclusively, AKK might mediate SCFAs-SLC52A2/FFAR2 pathways to exert protective activities against intestinal inflammatory response in UC, suggesting that AKK might represent a novel and promising candidate for UC therapy.

Clonal Hematopoiesis of Indeterminate Potential in Crohn's Disease and Ulcerative Colitis

BACKGROUND

Clonal hematopoiesis of indeterminate potential (CHIP) is the presence of somatic mutations in myeloid and lymphoid malignancy genes in the blood cells of individuals without a hematologic malignancy. Inflammation is hypothesized to be a key mediator in the progression of CHIP to hematologic malignancy and patients with CHIP have a high prevalence of inflammatory diseases. This study aimed to identify the prevalence and characteristics of CHIP in patients with inflammatory bowel disease (IBD).

METHODS

We analyzed whole-exome sequencing data from 587 Crohn's disease (CD), 441 ulcerative colitis (UC), and 293 non-IBD controls to assess CHIP prevalence and used logistic regression to study associations with clinical outcomes.

RESULTS

Older UC patients (age > 45) harbored increased myeloid-CHIP mutations compared to younger patients (age ≤ 45) (P = .01). Lymphoid-CHIP was more prevalent in older IBD patients (P = .007). Young CD patients were found to have myeloid-CHIP with high-risk features. Inflammatory bowel disease patients with CHIP exhibited unique mutational profiles compared to controls. Steroid use was associated with increased CHIP (P = .05), while anti-TNF therapy was associated with decreased myeloid-CHIP (P = .03). Pathway enrichment analyses indicated an overlap between CHIP genes, IBD phenotypes, and inflammatory pathways.

CONCLUSIONS

Our findings underscore a connection between IBD and CHIP pathophysiology. Patients with IBD and CHIP had unique risk profiles, especially among older UC patients and younger CD patients. These findings suggest distinct evolutionary pathways for CHIP in IBD and necessitate awareness among IBD providers and hematologists to identify patients potentially at risk for CHIP-related complications including malignancy, cardiovascular disease, and acceleration of their inflammatory disease.

Eleven Grand Challenges for Inflammatory Bowel Disease Genetics and Genomics

The past 2 decades have witnessed extraordinary advances in our understanding of the genetic factors influencing inflammatory bowel disease (IBD), providing a foundation for the approaching era of genomic medicine. On behalf of the NIDDK IBD Genetics Consortium, we herein survey 11 grand challenges for the field as it embarks on the next 2 decades of research utilizing integrative genomic and systems biology approaches. These involve elucidation of the genetic architecture of IBD (how it compares across populations, the role of rare variants, and prospects of polygenic risk scores), in-depth cellular and molecular characterization (fine-mapping causal variants, cellular contributions to pathology, molecular pathways, interactions with environmental exposures, and advanced organoid models), and applications in personalized medicine (unmet medical needs, working toward molecular nosology, and precision therapeutics). We review recent advances in each of the 11 areas and pose challenges for the genetics and genomics communities of IBD researchers.

Therapeutic efficacy of jeoryeong-tang in dextran sulfate sodium-induced mouse model of inflammatory bowel disease

Background

Jeoryeong-tang (JRT) was first recorded in Shanghanlun. It is composed of Polyporus Sclerotium, Poria, Asini Corii Colla, Alisma Rhizome, and Talcum at the same weight ratio. These medicinal materials are known for diuretic and hemostatic effects and have been traditionally used to treat kidney and bladder diseases. However, their potential therapeutic effects on colon diseases, particularly inflammatory bowel disease (IBD), have not been extensively studied. Therefore, this study aimed to investigate the therapeutic efficacy of JRT in IBD and explore its underlying anti-inflammatory mechanisms using a murine model of colitis induced by dextran sulfate sodium (DSS).

Methods

Mice were treated with 3.0 % or 2.5 % DSS for 6 days to induce colitis and JRT extract was then administered at a low level of 40 mg/kg (JRT-L), a medium level of 120 mg/kg (JRT-M), or a high level of 400 mg/kg (JRT-H) once a day. During the administration period, clinical disease activity index (DAI) reflecting survival rate, diarrhea, bloody stool, and weight loss rate was evaluated. The degree of colonic tissue damage was scored and evaluated through hematoxylin and eosin staining. Cyclooxygenase-2 (COX-2), p-STAT3 and p-ERK expression were examined with immunohistochemistry. Tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and -1β levels were analyzed using a cytokine enzyme-linked immunosorbent assay.

Results

Among mice treated with 3.0 % DSS, JRT-M significantly improved the survival rate compared to other treatments as a result of observation for a total of 14 days. While, in the 2.5 % DSS-treated model, the average body weights of mice in both of JRT-M and JRT-H groups were significantly higher than that in the DSS group. In addition, the JRT-M group showed significantly lower DAI score than that in the DSS group. As a result of evaluating the extent of colon tissue damage, JRT-M and JRT-H groups both showed significantly lower inflammatory index and thinner muscular externa thickness than the DSS group. The expression of COX-2, p-STAT3 and p-ERK in colon tissue were significantly suppressed in JRT-M and JRT-H groups compared to that in the DSS group. Moreover, serum TNF-α was significantly suppressed in the JRT-H group compared to that in the DSS group.

Conclusions

Jeoryeong-tang has a promising therapeutic potential for treating IBD through its anti-inflammatory properties. Findings of this study suggest that JRT could be a valuable candidate for further clinical investigations in the treatment of IBD.

Effects of traditional Chinese medicine polysaccharides on chronic diseases by modulating gut microbiota: A review

Intestinal tract is the largest immune system of human body. Gut microbiota (GM) can produce a large number of metabolites, such as short-chain fatty acids and bile acids, which regulate the physiological health of the host and affect the development of disease. In recent years, traditional Chinese medicine (TCM) polysaccharides have attracted extensive attention with multiple biological activities and low toxicity. TCM polysaccharides can promote the growth of intestinal beneficial bacteria and inhibit the growth of harmful bacteria by regulating the structure and function of GM, thus playing a crucial role in preventing or treating chronic diseases such as inflammatory bowel disease (IBD), obesity, type 2 diabetes mellitus (T2DM), liver diseases, cancer, etc. In this paper, the research progress of TCM polysaccharides in the treatment of chronic diseases such as inflammatory bowel disease, obesity, T2DM, liver diseases, cancer, etc. by modulating GM was reviewed. Meanwhile, this review makes an in-depth discussion on the shortcomings of the research of TCM polysaccharides on chronic diseases by modulating GM, and new valuable prospection for the future researches of TCM polysaccharides are proposed, which will provide new ideas for the further study of TCM polysaccharides.

Exploring the potential use of Caenorhabditis elegans as an animal model for evaluating chemical-induced intestinal dysfunction

Evaluating intestinal toxicity is crucial for identifying and preventing the harmful effects of environmental chemicals. Owing to the limitations of existing models in evaluating intestinal toxicity, the development of alternative models is urgently needed. This study explored the potential use of the nematode Caenorhabditis elegans as a model animal for assessing chemical-induced intestinal dysfunction. Changes in intestinal permeability and nutrient absorption in C. elegans individuals exposed to four intestine-disrupting chemicals (sodium dodecyl sulfate (SDS), dextran sulfate sodium (DSS), lipopolysaccharide (LPS) and ethanol) were examined using dye stain assays, an enzymatic photometric assay, and fluorescent probe uptake assays. Additionally, epigallocatechin-3-gallate (EGCG), an intestine-protecting phytochemical, was chosen to prevent ethanol-induced intestinal damage. The results indicated that SDS, DSS, LPS, and ethanol compromised the intestinal barrier in C. elegans. SDS had no effect on glucose absorption, but LPS, DSS, and ethanol inhibited or tended to inhibit glucose absorption. SDS, DSS, LPS, and ethanol reduced fatty acid absorption. LPS increased peptide absorption at a low dose but decreased it at a high dose; SDS, DSS, and ethanol attenuated peptide absorption. EGCG protected against the disruption of the intestinal barrier that was induced by ethanol treatment. These results suggest that C. elegans is a suitable surrogate model animal for evaluating chemical-induced intestinal dysfunction. These findings also provide new insights into the effects of SDS, DSS, LPS, and ethanol on intestinal function and highlight the potential of EGCG as a natural dietary intervention to protect individuals who use excess alcohol from intestinal injury.

Epithelial-specific loss of Smad4 alleviates the fibrotic response in an acute colitis mouse model

Mucosal healing is associated with better clinical outcomes in patients with inflammatory bowel disease. But the epithelial-specific contribution to mucosal healing in vivo is poorly understood. We evaluated mucosal healing in an acute dextran sulfate sodium mouse model that shows an alleviated colitis response after epithelial-specific loss of Smad4. We find that enhanced epithelial wound healing alleviates the fibrotic response. Dextran sulfate sodium caused increased mesenchymal collagen deposition-indicative of fibrosis-within a week in the WT but not in the Smad4 KO colon. The fibrotic response correlated with decreased epithelial proliferation in the WT, whereas uninterrupted proliferation and an expanded zone of proliferation were observed in the Smad4 KO colon epithelium. Furthermore, the Smad4 KO colon showed epithelial extracellular matrix alterations that promote epithelial regeneration. Our data suggest that epithelium is a key determinant of the mucosal healing response in vivo, implicating mucosal healing as a strategy against fibrosis in inflammatory bowel disease patients.

Targeted nuclear degranulation of neutrophils promotes the progression of pneumonia in ulcerative colitis

Background

Both intestinal and pulmonary systems are parts of the mucosal immune system, comprising ∼80% of all immune cells. These immune cells migrate or are transported between various mucosal tissues to maintain tissue homeostasis.

Methods

In this study, we isolated neutrophils from the peripheral blood of patients and utilized immunofluorescence, flow cytometry, and Western blotting to confirm the incidence of "nucleus-directed degranulation" in vitro. Subsequently, we conducted a precise analysis using arivis software. Furthermore, using the DSS mouse model of colitis and tissue clearing technologies, we validated the "targeted nuclear degranulation" of neutrophils and their migration to the lungs in an inflammatory intestinal environment.

Result

In this study, we found that among patients with ulcerative colitis, the migration of neutrophils with "targeted nuclear degranulation" from the intestinal mucosa to the lungs significantly exacerbates lung inflammation during pulmonary infections. Notably, patients with ulcerative colitis exhibited a higher abundance of neutrophils with targeted nuclear degranulation. Using DSS mice, we observed that neutrophils with targeted nuclear degranulation from the intestinal mucosa migrated to the lung and underwent activation during pulmonary infections. These neutrophils rapidly released a high amount of neutrophil extracellular traps to mediate the progression of lung inflammation. Alterations in the neutrophil cytoskeleton and its interaction with the nuclear membrane represent the primary mechanisms underlying targeted nuclear degranulation.

Conclusion

This study revealed that neutrophils accelerate lung inflammation progression in colitis, offering new insights and potential treatment targets for lung infections for patients with colitis.

Qing Hua Chang Yin ameliorates chronic colitis in mice by inhibiting PERK-ATF4-CHOP pathway of ER stress and the NF-κB signalling pathway

CONTEXT

Ulcerative colitis has been clinically treated with Qing Hua Chang Yin (QHCY), a traditional Chinese medicine formula. However, its precise mechanisms in mitigating chronic colitis are largely uncharted.

OBJECTIVE

To elucidate the therapeutic efficiency of QHCY on chronic colitis and explore its underlying molecular mechanisms.

MATERIALS AND METHODS

A total ion chromatogram fingerprint of QHCY was analysed. Chronic colitis was induced in male C57BL/6 mice using 2% dextran sodium sulphate (DSS) over 49 days. Mice were divided into control, DSS, DSS + QHCY (0.8, 1.6 and 3.2 g/kg/d dose, respectively) and DSS + mesalazine (0.2 g/kg/d) groups (n = 6). Mice were intragastrically administered QHCY or mesalazine for 49 days. The changes of disease activity index (DAI), colon length, colon histomorphology and serum pro-inflammatory factors in mice were observed. RNA sequencing was utilized to identify the differentially expressed transcripts (DETs) in colonic tissues and the associated signalling pathways. The expression of endoplasmic reticulum (ER) stress-related protein and NF-κB signalling pathway-related proteins in colonic tissues was detected by immunohistochemistry staining.

RESULTS

Forty-seven compounds were identified in QHCY. Compared with the DSS group, QHCY significantly improved symptoms of chronic colitis like DAI increase, weight loss, colon shortening and histological damage. It notably reduced serum levels of IL-6, IL-1β and TNF-α. QHCY suppressed the activation of PERK-ATF4-CHOP pathway of ER stress and NF-κB signalling pathways in colonic tissues.

DISCUSSION AND CONCLUSIONS

The findings in this study provide novel insights into the potential of QHCY in treating chronic colitis patients.

Coloprotective effects of chebulic myrobalan extract by regulation of AMPK-SIRT1 signaling: A pharmacological and histopathological evaluation

Ulcerative colitis is a chronic, refractory disease caused by dysregulation of mucosal immune responses to the indigenous bacterial flora as well as genetic and environmental variables. Recently, there has been increasing interest towards the use of herbal medicines for the treatment of ulcerative colitis and the potential benefits could lie in their high patient acceptability, effectiveness, safety, and relatively low cost. It has been reported that Chebulic myrobalan (Terminalia chebula) exhibits anti-oxidant, anti-inflammatory and immunomodulatory properties. The present study was designed to evaluate the protective potential of extract of dried fruit pulp of T. chebula against Dextran sulphate sodium (DSS)-induced ulcerative colitis in male BALB/c mice. Three cycles of DSS (3 % w/v in drinking water), each followed by a seven-day remission phase were used to induce ulcerative colitis in mice. Animals were treated with T. chebula (300 mg/kg and 600 mg/kg) starting from Ist remission period to the end of the study. Different biochemical assays, histological evaluation and molecular analysis were performed to evaluate the protective effects of T. chebula extract in DSS induced colitis. T. chebula modulates the expression of nuclear factor kappa B, adenosine monophosphate kinase, tumour necrosis factor-alpha, sirtuin 1 and interleukin-1β. Furthermore, it also accorded coloprotective effects against DNA damage, apoptosis, inflammation and nitrosative stress. Finally, it was found that the high dose of the T. chebula extract (600 mg/kg) was found to be more effective than a low dose (300 mg/kg) in restoring the ulcerative colitis induced colonic damage.

PLGA microspheres carrying EMSCs-CM for the effective treatment of murine ulcerative colitis

Ectodermal mesenchymal stem cells-derived conditioned medium (EMSCs-CM) has been reported to protect against ulcerative colitis (UC) in mice, but its underlying mechanism in alleviating UC need to be further elucidated. Here, it is reported that EMSCs-CM could attenuate pro-inflammatory response of LPS-induced IEC-6 cells and regulate the polarization of macrophages towards anti-inflammatory type in vitro. Furthermore, PLGA microspheres prepared by the double emulsion method were constructed for oral delivery of EMSCs-CM (EMSCs-CM-PLGA), which are beneficial for colon-targeted adhesion of EMSCs-CM to the damaged colon mucosa. The results showed that orally-administered of EMSCs-CM-PLGA microspheres reduced inflammatory cells infiltration and maintained the intestinal mucosal barrier. Further investigation found that EMSCs-CM-PLGA microspheres treatment gradually inhibited the activation of NF-κB pathway to regulate M1/M2 polarization balance in colon tissue macrophages, thereby alleviating DSS-induced UC. These results of this study will provide a theoretical basis for clinical application of EMSCs-CM in UC repair.

Bacteroides vesicles promote functional alterations in the gut microbiota composition

Inflammatory bowel diseases are characterized by chronic intestinal inflammation and alterations in the gut microbiota composition. Bacteroides fragilis, which secretes outer membrane vesicles (OMVs) with polysaccharide A (PSA), can moderate the inflammatory response and possibly alter the microbiota composition. In this study, we created a murine model of chronic sodium dextran sulfate (DSS)-induced intestinal colitis and treated it with B. fragilis OMVs. We monitored the efficiency of OMV therapy by determining the disease activity index (DAI) and performing histological examination (HE) of the intestine before and after vesicle exposure. We also analyzed the microbiota composition using 16S rRNA gene sequencing. Finally, we evaluated the volatile compound composition in the animals' stools by HS-GC/MS to assess the functional activity of the microbiota. We observed more effective intestinal repair after OMV treatment according to the DAI and HE. A metabolomic study also revealed changes in the functional activity of the microbiota, with a predominance of phenol and pentanoic acid in the control group compared to the group treated with DSS and the group treated with OMVs (DSS OMVs). We also observed a positive correlation of these metabolites with Saccharibacteria and Acetivibrio in the control group, whereas in the DSS group, there was a negative correlation of phenol and pentanoic acid with Lactococcus and Romboutsia. According to the metabolome and sequencing data, the microbiota composition of the DSS-treated OMV group was intermediate between that of the control and DSS groups. OMVs not only have an anti-inflammatory effect but also contribute to the recovery of the microbiota composition.IMPORTANCEBacteroides fragilis vesicles contain superficially localized polysaccharide A (PSA), which has unique immune-modulating properties. Isolated PSA can prevent chemically induced colitis in a murine model. Outer membrane vesicles (OMVs) also contain digestive enzymes and volatile metabolites that can complement the anti-inflammatory properties of PSA. OMVs showed high therapeutic activity against sodium dextran sulfate-induced colitis, as confirmed by histological assays. 16S rRNA sequencing of fecal samples from different inflammatory stages, supplemented with comprehensive metabolome analysis of volatile compounds conducted by HS-GC/MS, revealed structural and functional alterations in the microbiota composition under the influence of OMVs. Correlation analysis of the OMV-treated and untreated experimental animal groups revealed associations of phenol and pentanoic acid with Lactococcus, Romboutsia, Saccharibacteria, and Acetivibrio.

An Intelligent Intestine-on-a-Chip for Rapid Screening of Probiotics with Relief-Enteritis Function

Screening probiotics with specific functions is essential for advancing probiotic research. Current screening methods primarily use animal studies or clinical trials, which are inefficient and costly in terms of time, money, and labor. An intelligent intestine-on-a-chip integrating machine learning (ML) is developed to screen relief-enteritis functional probiotics. A high-throughput microfluidic chip combined with environment control systems provides a standardized and scalable intestinal microenvironment for multiple probiotic cocultures. An unsupervised ML-based score analyzer is constructed to accurately, comprehensively, and efficiently evaluate interactions between 12 Bifidobacterium strains and host cells of the colitis model in the intestine-on-a-chips. The most effective contender, Bifidobacterium longum 3-14, is discovered to relieve intestinal inflammation and enhance epithelial barrier function in vitro and in vivo. A distinct advantage of this strategy is that it can intelligently differentiate small therapeutic variations in probiotic strains and prioritize their efficacies, allowing for economical, efficient, accurate functional probiotics screening.

The Effects of Interventions with Glucosinolates and Their Metabolites in Cruciferous Vegetables on Inflammatory Bowel Disease: A Review

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract which affects millions of individuals worldwide. Despite advancements in treatment options, there is increasing interest in exploring natural interventions with minimal side effects. Cruciferous vegetables, such as broccoli, cabbage, and radishes, contain bioactive compounds known as glucosinolates (GLSs), which have shown promising effects in alleviating IBD symptoms. This review aims to provide a comprehensive overview of the physiological functions and mechanisms of cruciferous GLSs and their metabolites in the context of IBD. Reviewed studies demonstrated that GLSs attenuated all aspects of IBD, including regulating the intestinal microbiota composition, exerting antioxidant and anti-inflammatory effects, restoring intestinal barrier function, and regulating epigenetic mechanisms. In addition, a few interventions with GLS supplementation in clinical studies were also discussed. However, there are still several challenges and remaining knowledge gaps, including variations in animals' experimental outcomes, the bioavailability of certain compounds, and few clinical trials to validate their effectiveness in human subjects. Addressing these issues will contribute to a better understanding of the therapeutic potential of cruciferous GLSs and their metabolites in the management of IBD.

Systemic and local lipid adaptations underlie regeneration in Drosophila melanogaster and Ambystoma mexicanum

In regenerating tissues, synthesis and remodeling of membranes rely on lipid turnover and transport. Our study addresses lipid adaptations in intestinal regeneration of Drosophila melanogaster and limb regeneration of Ambystoma mexicanum. We found changes in lipid profiles at different locations: transport, storage organs and regenerating tissues. We demonstrate that attenuating insulin signaling, exclusively in fat storage, inhibits the regeneration-specific response in both the fat storage and the regenerating tissue in Drosophila. Furthermore, in uninjured axolotls we found sex-specific lipid profiles in both storage and circulation, while in regenerating animals these differences subside. The regenerating limb presents a unique sterol profile, albeit with no sex differences. We postulate that regeneration triggers a systemic response, where organs storing lipids play a significant role in the regulation of systemic lipid traffic. Second, that this response may be an active and well-regulated mechanism, as observed when homeostatic sex-differences disappear in regenerating salamanders.

Morin alleviates DSS-induced ulcerative colitis in mice via inhibition of inflammation and modulation of intestinal microbiota

Ulcerative colitis (UC) is a chronic inflammatory condition with recurrent and challenging symptoms. Effective treatments are lacking, making UC management a critical research area. Morin (MO), a flavonoid from the Moraceae family, shows potential as an anti-UC agent, but its mechanisms are not fully understood. Using a dextran sulfate sodium (DSS)-induced UC mouse model, we employed network pharmacology to predict MO's therapeutic effects. Assessments included changes in body weight, disease activity index (DAI), and colon length. Immunofluorescence, hematoxylin and eosin (H&E), and PAS staining evaluated colon damage. ELISA and western blot analyzed inflammatory factors, tight junction (TJ)-associated proteins (Claudin-3, Occludin, ZO-1), and Mitogen-Activated Protein Kinase (MAPK)/ Nuclear Factor kappa B (NF-κB) pathways. 16S rRNA sequencing assessed gut microbiota diversity, confirmed by MO's modulation via Fecal Microbial Transplantation (FMT). Early MO intervention reduced UC severity by improving weight, DAI scores, and colon length, increasing goblet cells, enhancing barrier function, and inhibiting MAPK/NF-κB pathways. MO enriched gut microbiota, favoring beneficial bacteria like Muribaculaceae and Erysipelotrichaceae while reducing harmful Erysipelotrichaceae and Muribaculaceae. This study highlights MO's potential in UC management through inflammation control, mucosal integrity maintenance, and gut flora modulation.

Persistent Activation of the P2X7 Receptor Underlies Chronic Inflammation and Carcinogenic Changes in the Intestine

Aberrant signaling through damage-associated molecular patterns (DAMPs) has been linked to several health disorders, attracting considerable research interest over the last decade. Adenosine triphosphate (ATP), a key extracellular DAMP, activates the purinergic receptor P2X7, which acts as a danger sensor in immune cells and is implicated in distinct biological functions, including cell death, production of pro-inflammatory cytokines, and defense against microorganisms. In addition to driving inflammation mediated by immune and non-immune cells, the persistent release of endogenous DAMPs, including ATP, has been shown to result in epigenetic modifications. In intestinal diseases such as inflammatory bowel disease (IBD) and colorectal cancer (CRC), consequent amplification of the inflammatory response and the resulting epigenetic reprogramming may impact the development of pathological changes associated with specific disease phenotypes. P2X7 is overexpressed in the gut mucosa of patients with IBD, whereas the P2X7 blockade prevents the development of chemically induced experimental colitis. Recent data suggest a role for P2X7 in determining gut microbiota composition. Regulatory mechanisms downstream of the P2X7 receptor, combined with signals from dysbiotic microbiota, trigger intracellular signaling pathways and inflammasomes, intensify inflammation, and foster colitis-associated CRC development. Preliminary studies targeting the ATP-P2X7 pathway have shown favorable therapeutic effects in human IBD and experimental colitis.

An injectable subcutaneous colon-specific immune niche for the treatment of ulcerative colitis

As a chronic autoinflammatory condition, ulcerative colitis is often managed via systemic immunosuppressants. Here we show, in three mouse models of established ulcerative colitis, that a subcutaneously injected colon-specific immunosuppressive niche consisting of colon epithelial cells, decellularized colon extracellular matrix and nanofibres functionalized with programmed death-ligand 1, CD86, a peptide mimic of transforming growth factor-beta 1, and the immunosuppressive small-molecule leflunomide, induced intestinal immunotolerance and reduced inflammation in the animals' lower gastrointestinal tract. The bioengineered colon-specific niche triggered autoreactive T cell anergy and polarized pro-inflammatory macrophages via multiple immunosuppressive pathways, and prevented the infiltration of immune cells into the colon's lamina propria, promoting the recovery of epithelial damage. The bioengineered niche also prevented colitis-associated colorectal cancer and eliminated immune-related colitis triggered by kinase inhibitors and immune checkpoint blockade.

The miRNA Landscape in Crohn's disease: Implications for novel therapeutic approaches and interactions with Existing therapies

MicroRNAs (miRNAs), which are non-coding RNAs consisting of 18-24 nucleotides, play a crucial role in the regulatory pathways of inflammatory diseases. Several recent investigations have examined the potential role of miRNAs in forming Crohn's disease (CD). It has been suggested that miRNAs serve as diagnostics for both fibrosis and inflammation in CD due to their involvement in the mechanisms of CD aggravation and fibrogenesis. More information on CD pathophysiology could be obtained by identifying the miRNAs concerned with CD and their target genes. These findings have prompted several in vitro and in vivo investigations into the putative function of miRNAs in CD treatment. Although there are still many unanswered questions, the growing body of evidence has brought miRNA-based therapy one step closer to clinical practice. This extensive narrative study offers a concise summary of the most current advancements in CD. We go over what is known about the diagnostic and therapeutic benefits of miRNA mimicry and inhibition so far, and we see what additional miRNA family targets could be useful for treating CD-related inflammation and fibrosis.

Exploring the anti-inflammatory effects of postbiotic proteins from Lactobacillus delbrueckii CIDCA 133 on inflammatory bowel disease model

Lactobacillus delbrueckii CIDCA 133 is a promising health-promoting bacterium shown to alleviate intestinal inflammation. However, the specific bacterial components responsible for these effects remain largely unknown. Here, we demonstrated that consuming extractable proteins from the CIDCA 133 strain effectively relieved acute ulcerative colitis in mice. This postbiotic protein fraction reduced the disease activity index and prevented colon shortening in mice. Furthermore, histological analysis revealed colitis prevention with reduced inflammatory cell infiltration into the colon mucosa. Postbiotic consumption also induced an immunomodulatory profile in colitic mice, as evidenced by both mRNA transcript levels (Tlr2, Nfkb1, Nlpr3, Tnf, and Il6) and cytokines concentration (IL1β, TGFβ, and IL10). Additionally, it enhanced the levels of secretory IgA, upregulated the transcript levels of tight junction proteins (Hp and F11r), and improved paracellular intestinal permeability. More interestingly, the consumption of postbiotic proteins modulated the gut microbiota (Bacteroides, Arkkemansia, Dorea, and Oscillospira). Pearson correlation analysis indicated that IL10 and IL1β levels were positively associated with Bacteroides and Arkkemansia_Lactobacillus abundance. Our study reveals that CIDCA 133-derived proteins possess anti-inflammatory properties in colonic inflammation.

Huang Lian Jie Du decoction attenuated colitis via suppressing the macrophage Csf1r/Src pathway and modulating gut microbiota

Introduction

Ulcerative colitis, a subtype of chronic inflammatory bowel disease (IBD), is characterized by relapsing colonic inflammation and ulcers. The traditional Chinese herbal formulation Huang Lian Jie Du (HLJD) decoction is used clinically to treat diarrhea and colitis. However, the mechanisms associated with the effects of treatment remain unclear. This study aims to elucidate the molecular mechanistic effects of HLJD formulation on colitis.

Methods

Chronic colitis in mice was induced by adding 1% dextran sulfate sodium (DSS) to their drinking water continuously for 8 weeks, and HLJD decoction at the doses of 2 and 4 g/kg was administered orally to mice daily from the second week until experimental endpoint. Stool consistency scores, blood stool scores, and body weights were recorded weekly. Disease activity index (DAI) was determined before necropsy, where colon tissues were collected for biochemical analyses. In addition, the fecal microbiome of treated mice was characterized using 16S rRNA amplicon sequencing.

Results

HLJD decoction at doses of 2 and 4 g/kg relieved DSS-induced chronic colitis in mice by suppressing inflammation through compromised macrophage activity in colonic tissues associated with the colony-stimulating factor 1 receptor (Csf1r)/Src pathway. Furthermore, the HLJD formula could modify the gut microbiota profile by decreasing the abundance of Bacteroides, Odoribacter, Clostridium_sensu_stricto_1, and Parasutterella. In addition, close correlations between DAI, colon length, spleen weight, and gut microbiota were identified.

Discussion

Our findings revealed that the HLJD formula attenuated DSS-induced chronic colitis by reducing inflammation via Csf1r/Src-mediated macrophage infiltration, as well as modulating the gut microbiota profile.

Neohesperidin Attenuates DSS-Induced Ulcerative Colitis by Inhibiting Inflammation, Reducing Intestinal Barrier Damage, and Modulating Intestinal Flora Composition

Flavonoid natural products are emerging as a promising approach for treating Ulcerative Colitis (UC) due to their natural origin and minimal toxicity. This study investigates the effects of Neohesperidin (NEO), a natural flavonoid, on Dextran Sodium Sulfate (DSS)-induced UC in mice, focusing on the underlying molecular mechanisms. Early intervention with NEO (25 and 50 mg/kg) mitigated colon shortening, restored damaged barrier proteins, and significantly reduced the inflammatory cytokine levels. Moreover, NEO inhibited the MAPK/NF-κB signaling pathway and enhanced the levels of intestinal barrier proteins (Claudin-3 and ZO-1). Additionally, NEO increased beneficial intestinal probiotics (S24-7 and Lactobacillaceae) while reducing harmful bacteria (Erysipelotrichi, Enterobacteriaceae). Fecal microbial transplantation (FMT) results demonstrated that NEO (50 mg/kg) markedly improved UC symptoms. In conclusion, early NEO intervention may alleviate DSS-induced UC by inhibiting inflammatory responses, preserving intestinal barrier integrity and modulating gut microbiota.

Abdel-Wareth M, Hassan M. Helix pomatia mucin alleviates DSS-induced colitis in mice: Unraveling the cross talk between microbiota and intestinal chemokine

Gut microbiota imbalance and alterations in the chemokine-chemokine receptor interactions are pivotal in the initiation and advancement of ulcerative colitis (UC). The current UC treatments are prolonged, exhibit high recurrence rates, and may lead to colorectal cancer. So, this study explores the efficacy of Helix pomatia (H. pomatia) mucin in preventing DSS-induced UC. This research focuses on investigating the underlying mechanisms, such as oxidative stress, inflammation, and alterations in gut microbiota and chemokine-chemokine receptor interactions, to understand the anti-inflammatory and antioxidant characteristics of the mucin. Using 4 % DSS in drinking water, UC was induced in C57BL/6 mice. For seven days, mice were given oral doses of either H. pomatia mucin or sulfasalazine. The study assessed changes in oxidative stress, gut microbiota, and histopathology, along with expression of IL-6, CXCR4, CCR7, CXCL9, and CXCL10. The H. pomatia mucin exhibited unique contents, including high glycolic acid (200 ± 2.08 mg/L), collagen (88 ± 2.52 mg/L), allantoin (20 ± 2 mg/L), and concentrated vitamins and minerals. Treatment with H. pomatia mucin in high dose demonstrated reduction in DAI, an increase in fecal Firmicutes, and elevated expression of colonic CCR7, CXCL9, and CXCL10, accompanied by enhanced CXCR4 (75 %) and diminished IL-6 (1.33 %) immunostaining. It also alleviated oxidative stress, reduced fecal Bacteroidetes, and mitigated inflammation, indicating its potential efficacy against DSS-induced UC. In conclusion, H. pomatia mucin is a promising candidate that could be an effective adjuvant in the management and prophylaxis of UC.