Charting the cellular biogeography in colitis reveals fibroblast trajectories and coordinated spatial remodeling.

Gut inflammation involves contributions from immune and non-immune cells, whose interactions are shaped by the spatial organization of the healthy gut and its remodeling during inflammation. The crosstalk between fibroblasts and immune cells is an important axis in this process, but our understanding has been challenged by incomplete cell-type definition and biogeography. To address this challenge, we used multiplexed error-robust fluorescence in situ hybridization (MERFISH) to profile the expression of 940 genes in 1.35 million cells imaged across the onset and recovery from a mouse colitis model. We identified diverse cell populations, charted their spatial organization, and revealed their polarization or recruitment in inflammation. We found a staged progression of inflammation-associated tissue neighborhoods defined, in part, by multiple inflammation-associated fibroblasts, with unique expression profiles, spatial localization, cell-cell interactions, and healthy fibroblast origins. Similar signatures in ulcerative colitis suggest conserved human processes. Broadly, we provide a framework for understanding inflammation-induced remodeling in the gut and other tissues.

Rab7-dependent regulation of goblet cell protein CLCA1 modulates gastrointestinal homeostasis.

Inflammation in ulcerative colitis is typically restricted to the mucosal layer of distal gut. Disrupted mucus barrier, coupled with microbial dysbiosis, has been reported to occur prior to the onset of inflammation. Here, we show the involvement of vesicular trafficking protein Rab7 in regulating the colonic mucus system. We identified a lowered Rab7 expression in goblet cells of colon during human and murine colitis. In vivo Rab7 knocked down mice (Rab7KD) displayed a compromised mucus layer, increased microbial permeability, and depleted gut microbiota with enhanced susceptibility to dextran sodium-sulfate induced colitis. These abnormalities emerged owing to altered mucus composition, as revealed by mucus proteomics, with increased expression of mucin protease chloride channel accessory 1 (CLCA1). Mechanistically, Rab7 maintained optimal CLCA1 levels by controlling its lysosomal degradation, a process that was dysregulated during colitis. Overall, our work establishes a role for Rab7-dependent control of CLCA1 secretion required for maintaining mucosal homeostasis.

Correlation between neuregulin receptor degradation protein-1 and Crohn's disease.

Neuregulin receptor degradation protein-1 (Nrdp1) is a newly discovered E3 ligase that plays a role in the apoptosis process of multiple diseases. Previous studies has shown that Nrdp1 exerted a proapoptotic effect in cardiac diseases. The purpose of this study is to investigate the potential involvement of Nrdp1 in the pathological processes of inflammatory bowel disease (IBD). To create a mouse model of experimental colitis, trinitrobenzenesulfonic acid (TNBS) was administered and the severity of colitis was assessed based on changes in weight and histological scores. Using Western blot and immunohistochemistry, significant increase in Nrdp1 expression was observed in intestinal epithelial cells (IECs). This was accompanied with the up-regulation of cleaved PARP and active caspase-3 in IECs, indicating a potential function in IECs. To study this further, we built an in vitro model of tumor necrosis factor-alpha (TNF-α)-induced apoptosis using human IEC line HT-29 cells. When Nrdp1 was knocked down, a decrease in apoptosis was observed, suggesting that Nrdp1 may play a proapoptotic role in IEC apoptosis. The mechanism behind this phenomenon is associated with the suppression of downstream targets of Nrdp1, such as protein kinase B (AKT). Furthermore, immunohistochemistry analysis in patients with Crohn's disease (CD) and normal controls supported the same results as observed in experimental colitis. We conclude that Nrdp1 may be a promising new therapeutic target for ameliorating IBD in humans.

Sarcandra glabra (Thunb.) Nakai alleviates DSS-induced ulcerative colitis by promoting restitution, restoring barrier function, and modulating IL-17/Notch1/FoxP3 pathway in intestinal cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Sarcandra glabra is officially named Zhong Jie Feng as a traditional medicine. In the nationality of Yao and Zhuang, it has been used to treat digestive diseases like stomachache and dysentery. Similarly, in Dai nationality, it has been used to treat intestinal diseases like gastric ulcers. However, the effect and mechanism of S. glabra on experimental ulcerative colitis (UC) are known. AIM OF STUDY: The main objective of this study was to investigate the effect and mechanism of S. glabra on experimental UC. MATERIALS AND METHODS: The chemical components in the water extract of S. glabra (ZJF) were analyzed by UPLC-MS/MS method. The HCoEpiC cell line was used to assess the promotive effect on intestinal proliferation and restitution. RAW264.7 cells were used to assess the in vitro anti-inflammatory effect of ZJF. The 3% DSS-induced colitis model was used to evaluate the in vivo effect of ZJF (4.5 g/kg and 9.0 g/kg). Mesalazine (0.5 g/kg) was used as the positive drug. ELISA, RT-qPCR, Western blot, and multiplex immunohistochemical experiments were used to test gene levels in the colon tissue. The H&E staining method was used to monitor the pathological changes of colon tissue. TUNEL assay kit was used to detect apoptosis of epithelial colonic cells. RESULTS: ZJF could alleviate the DSS-caused colitis in colon tissues, showing a comparative effect to that of the positive drug mesalazine. Mechanism study indicated that ZJF could promote normal colonic HCoEpiC cell proliferation and restitution, inhibit overexpression of pro-inflammatory cytokines, restore the M1/M2 ratio, decrease epithelial colonic cell apoptosis, rescue tight junction protein levels, and modulate IL-17/Notch1/FoxP3 pathway to treat experimental UC. CONCLUSION: Our results indicated that S. glabra can promote intestinal cell restitution, balance immune response, and modulate IL-17/Notch1/FoxP3 pathway to treat experimental UC.

Rauwolfia polysaccharide can inhibit the progress of ulcerative colitis through NOS2-mediated JAK2/STAT3 pathway.

BACKGROUND: Ulcerative colitis (UC) is an inflammatory disease of the digestive tract. Rauwolfia polysaccharide (Rau) has therapeutic effects on colitis in mice, but its mechanism of action needs to be further clarified. In the study, we explored the effect of Rau on the UC cell model induced by Lipopolysaccharide (LPS). METHODS: We constructed a UC cell model by stimulating HT-29 cells with LPS. Dextran sodium sulfate (DSS) was used to induce mice to construct an animal model of UC. Subsequently, we performed Rau administration on the UC cell model. Then, the therapeutic effect of Rau on UC cell model and was validated through methods such as Cell Counting Kit-8 (CCK8), Muse, Quantitative real­time polymerase chain reaction (RT-qPCR), Western blotting, and Enzyme-linked immunosorbent assay (ELISA). RESULTS: The results showed that Rau can promote the proliferation and inhibit the apoptosis of the HT-29 cells-induced by LPS. Moreover, we observed that Rau can inhibit the expression of NOS2/JAK2/STAT3 in LPS-induced HT-29 cells. To further explore the role of NOS2 in UC progression, we used siRNA technology to knock down NOS2 and search for its mechanism in UC. The results illustrated that NOS2 knockdown can promote proliferation and inhibit the apoptosis of LPS-induced HT-29 cells by JAK2/STAT3 pathway. In addition, in vitro and in vivo experiments, we observed that the activation of the JAK2/STAT3 pathway can inhibit the effect of Rau on DSS-induced UC model. CONCLUSION: In short, Rauwolfia polysaccharide can inhibit the progress of ulcerative colitis through NOS2-mediated JAK2/STAT3 pathway. This study provides a theoretical clue for the treatment of UC by Rau.

Anchang Yuyang Decoction inhibits experimental colitis-related carcinogenesis by regulating PPAR signaling pathway and affecting metabolic homeostasis of host and microbiota.

ETHNOPHARMACOLOGICAL RELEVANCE: Inflammatory bowel disease (IBD) presents a risk of carcinogenesis, which escalates with the duration of IBD. Persistent histological inflammation is considered to be the driving factor of colitis carcinogenesis. Effective control of inflammation is helpful to prevent and treat colitis-related colorectal cancer (CAC). Anchang Yuyang Decoction (AYD), a traditional Chinese medicine (TCM) formula, is originated from the ancient prescription of TCM for treating colitis and colorectal cancer. AYD has demonstrated efficacy in treating IBD and potential anti-carcinogenic properties. AIM OF THE STUDY: This research aims to assess the therapeutic efficacy of AYD in ameliorating experimental colitis-related carcinogenesis induced by AOM/DSS. It further seeks to elucidate its potential mechanisms by integrating multiple omics sequencing approaches. MATERIALS AND METHODS: A rat model for colitis-related carcinogenesis was developed using azoxymethane (AOM)/dextran sulfate sodium (DSS). UPLC-MS identified AYD's chemical constituents. Rats were administered varying doses of AYD (18.37, 9.19 and 4.59 g/kg) orally for 53 days, with mesalazine as a positive control. The study evaluated anti-carcinogenic effects by examining adenoma number, adenoma load, abnormal crypt foci (ACF), histopathological damage, and tumor-related protein expression. Anti-inflammatory and reparative effects were assessed through body weight, disease activity index (DAI), colon length, spleen index, inflammatory cytokine levels, and tight junction protein expression. The effects on intestinal microbiota and host metabolism were explored through 16S rRNA sequencing, targeted short-chain fatty acid (SCFA) metabonomics, and non-targeted colon metabolomics. Potential AYD targets were identified through transcriptomic sequencing and validated by qRT-PCR and western blotting. RESULTS: AYD significantly reduced adenoma number, adenoma load, neoplasm-associated lesions, ACF, and tumor-related protein expression (e.g., p53, PCNA) in AOM/DSS-induced rats, thus impeding colitis-related carcinogenesis progression. AYD also alleviated histopathological damage and inflammation, promoting intestinal mucosal barrier repair. Furthermore, AYD modulated intestinal flora structure, enhanced SCFA production, and regulated colon metabolites. Transcriptomic sequencing revealed a significant impact on the peroxisome proliferator-activated receptor (PPAR) signaling pathway. Subsequent qRT-PCR and western blotting experiments indicated AYD's influence in up-regulating PPAR-γ and down-regulating PPAR-α, PPAR-ß/δ, and related proteins (thrombomodulin [Thbd], fatty acid binding protein 5 [Fabp5], stearoyl-CoA desaturase 2 [Scd2], phospholipid transfer protein [Pltp]). CONCLUSIONS: This study demonstrates AYD's ability to inhibit experimental colitis-related carcinogenesis induced by AOM/DSS. Its mechanism likely involves modulation of the PPAR signaling pathway, impacting intestinal microbiota and host metabolic equilibrium.

Mannose enhances intestinal immune barrier function and dextran sulfate sodium salt-induced colitis in mice by regulating intestinal microbiota.

Background: Inflammatory bowel disease (IBD) greatly affects human quality of life. Mannose has been reported to be used to treat IBD, but the mechanism is currently unknown. Methods: C57/BL mice were used as research subjects, and the mouse acute colitis model was induced using dextran sulfate sodium salt (DSS). After oral administration of mannose, the body weights and disease activity index (DAI) scores of the mice were observed. The colon lengths, histopathological sections, fecal content microbial sequencing, colon epithelial inflammatory genes, and tight junction protein Occludin-1 expression levels were measured. We further used the feces of mice that had been orally administered mannose to perform fecal bacterial transplantation on the mice with DSS-induced colitis and detected the colitis-related indicators. Results: Oral administration of mannose increased body weights and colon lengths and reduced DAI scores in mice with DSS-induced colitis. In addition, it reduced the expression of colon inflammatory genes and the levels of serum inflammatory factors (TNF-α, IL-6, and IL-1ß), further enhancing the expression level of the colonic Occludin-1 protein and alleviating the toxic response of DSS to the intestinal epithelium of the mice. In addition, gut microbial sequencing revealed that mannose increased the abundance and diversity of intestinal flora. Additionally, after using the feces of the mannose-treated mice to perform fecal bacterial transplantation on the mice with DSS-induced colitis, they showed the same phenotype as the mannose-treated mice, and both of them alleviated the intestinal toxic reaction induced by the DSS. It also reduced the expression of intestinal inflammatory genes (TNF-α, IL-6, and IL-1ß) and enhanced the expression level of the colonic Occludin-1 protein. Conclusion: Mannose can treat DSS-induced colitis in mice, possibly by regulating intestinal microorganisms to enhance the intestinal immune barrier function and reduce the intestinal inflammatory response.

Sporisorium reilianum polysaccharides improve DSS-induced ulcerative colitis by regulating intestinal barrier function and metabolites.

This study investigated the regulatory effects of Sporisorium reilianum polysaccharides (SRPS) on metabolism and the intestinal barrier in mice with colitis induced by dextran sulfate sodium (DSS). SRPS were resistant to the digestion of saliva, gastric juices, and intestinal fluid. SRPS significantly reduced the disease activity index and inhibited DSS-induced colon shortening. The expression of proinflammatory cytokines in the colon was normal (P < 0.05). Acetic acid, propionic acid, butyric acid, isobutyric acid, and isovaleric acid contents increased. Moreover, 64 biomarker metabolites were affected, including 42 abnormal decreases and 22 abnormal increases caused by DSS, which targeted amino acid biosynthesis; tryptophan metabolism; protein digestion and absorption; aminoacyl-tRNA biosynthesis; and glycine, serine, and threonine metabolism. In addition, SRPS reduced goblet cell loss and increased mucin secretion. The short-chain fatty acid receptor GPR41 was activated, and zonula occludens-1 and occludin expression levels were upregulated. Epithelial cell apoptosis was inhibited by increased Bcl-2 and decreased Bax expression NLRP3, ASC, and caspase-1 protein levels decreased. Intestinal barrier damage improved, and colon inflammation was reduced. Thus, our preliminary findings reveal that SRPS regulates metabolism and has the potential to protect the intestinal barrier in ulcerative colitis mice.

Polyphenol-Rich Extract from 'Limoncella' Apple Variety Ameliorates Dinitrobenzene Sulfonic Acid-Induced Colitis and Linked Liver Damage.

Inflammatory bowel conditions can involve nearly all organ systems and induce pathological processes through increased oxidative stress, lipid peroxidation and disruption of the immune response. Patients with inflammatory bowel disease (IBD) are at high risk of having extra-intestinal manifestations, for example, in the hepatobiliary system. In 30% of patients with IBD, the blood values of liver enzymes, such as AST and ALT, are increased. Moreover, treatments for inflammatory bowel diseases may cause liver toxicity. Apple polyphenol extracts are widely acknowledged for their potential antioxidant effects, which help prevent damage from oxidative stress, reduce inflammation, provide protection to the liver, and enhance lipid metabolism. The aim of this study was to investigate whether the polyphenol apple extract from Malus domestica cv. 'Limoncella' (LAPE) may be an effective intervention for the treatment of IBD-induced hepatotoxicity. The LAPE was administrated in vivo by oral gavage (3-300 mg/kg) once a day for 3 consecutive days, starting 24 h after the induction of dinitro-benzenesulfonic acid (DNBS) colitis in mice. The results showed that LAPE significantly attenuated histological bowel injury, myeloperoxidase activity, tumor necrosis factor and interleukin (IL-1ß) expressions. Furthermore, LAPE significantly improved the serum lipid peroxidation and liver injury in DNBS-induced colitis, as well as reduced the nuclear transcription factor-kappaB activation. In conclusion, these results suggest that LAPE, through its antioxidant and anti-inflammatory properties, could prevent liver damage induced by inflammatory bowel disease.

HSPA9 reduction exacerbates symptoms and cell death in DSS-Induced inflammatory colitis.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition that is influenced by various factors, including environmental factors, immune responses, and genetic elements. Among the factors that influence IBD progression, macrophages play a significant role in generating inflammatory mediators, and an increase in the number of activated macrophages contributes to cellular damage, thereby exacerbating the overall inflammatory conditions. HSPA9, a member of the heat shock protein 70 family, plays a crucial role in regulating mitochondrial processes and responding to oxidative stress. HSPA9 deficiency disrupts mitochondrial dynamics, increasing mitochondrial fission and the production of reactive oxygen species. Based on the known functions of HSPA9, we considered the possibility that HSPA9 reduction may contribute to the exacerbation of colitis and investigated its relevance. In a dextran sodium sulfate-induced colitis mouse model, the downregulated HSPA9 exacerbates colitis symptoms, including increased immune cell infiltration, elevated proinflammatory cytokines, decreased tight junctions, and altered macrophage polarization. Moreover, along with the increased mitochondrial fission, we found that the reduction in HSPA9 significantly affected the superoxide dismutase 1 levels and contributed to cellular death. These findings enhance our understanding of the intricate mechanisms underlying colitis and contribute to the development of novel therapeutic approaches for this challenging condition.

Lycopene Ameliorated DSS-Induced Colitis by Improving Epithelial Barrier Functions and Inhibiting the Escherichia coli Adhesion in Mice.

Adherent-invasive Escherichia coli plays an important role in the pathogenesis of inflammatory bowel disease. Blocking the adhesion of E. coli to intestinal epithelial cells appears to be useful for attenuating inflammatory bowel disease. Lycopene has been reported to have anti-inflammatory and antimicrobial activities. The aim of this study was to test the intervention effect of lycopene on colitis in mice and to investigate the possible mechanism through which lycopene affects the adhesion of E. coli to intestinal epithelial cells. Lycopene (12 mg/kg BW) attenuated dextran sulfate sodium (DSS)-induced colitis, decreased the proportion of E. coli, and activated the NLR family pyrin domain containing 12 and inactivated nuclear factor kappa B pathways. Furthermore, lycopene inhibited the adhesion of E. coli O157:H7 to Caco-2 cells by blocking the interaction between E. coli O157:H7 and integrin ß1. Lycopene ameliorated DSS-induced colitis by improving epithelial barrier functions and inhibiting E. coli adhesion. Overall, these results show that lycopene may be a promising component for the prevention and treatment of colitis.

Gα12 and endoplasmic reticulum stress-mediated pyroptosis in a single cycle of dextran sulfate-induced mouse colitis.

Inflammatory bowel disease (IBD) pathogenesis involves complex inflammatory events and cell death. Although IBD involves mainly necrosis in the digestive tract, pyroptosis has also been recognized. Nonetheless, the underlying basis is elusive. Gα12/13 overexpression may affect endoplasmic reticulum (ER) stress. This study examined how Gα12/13 and ER stress affect pyroptosis using dextran sulfate sodium (DSS)-induced colitis models. Gα12/13 levels were increased in the distal and proximal colons of mice exposed to a single cycle of DSS, as accompanied by increases of IRE1α, ATF6, and p-PERK. Moreover, Il-6, Il-1ß, Ym1, and Arg1 mRNA levels were increased with caspase-1 and IL-1ß activation, supportive of pyroptosis. In the distal colon, RIPK1/3 levels were enhanced to a greater degree, confirming necroptosis. By contrast, the mice subjected to three cycles of DSS treatments showed decreases of Gα12/13, as accompanied by IRE1α and ATF6 suppression, but increases of RIPK1/3 and c-Cas3. AZ2 treatment, which inhibited Gα12, has an anti-pyroptotic effect against a single cycle of colitis. These results show that a single cycle of DSS-induced colitis may cause ER stress-induced pyroptosis as mediated by Gα12 overexpression in addition to necroptosis, but three cycles model induces only necroptosis, and that AZ2 may have an anti-pyroptotic effect.

Protective effect of sucrose esters from cape gooseberry (Physalis peruviana L.) in TNBS-induced colitis.

Phytotherapy is an attractive strategy to treat inflammatory bowel disease (IBD) that could be especially useful in developing countries. We previously demonstrated the intestinal anti-inflammatory effect of the total ethereal extract from the Physalis peruviana (Cape gooseberry) calyces in TNBS-induced colitis. This work investigates the therapeutic potential of Peruviose A and B, two sucrose esters that constitute the major metabolites of its calyces. The effect of the Peruvioses A and B mixture on TNBS-induced colitis was studied after 3 (preventive) and 15-days (therapy set-up) of colitis induction in rats. Colonic inflammation was assessed by measuring macroscopic/histologic damage, MPO activity, and biochemical changes. Additionally, LPS-stimulated RAW 264.7 macrophages were treated with test compounds to determine the effect on cytokine imbalance in these cells. Peruvioses mixture ameliorated TNBS-induced colitis in acute (preventive) or established (therapeutic) settings. Although 3-day treatment with compounds did not produce a potent effect, it was sufficient to significantly reduce the extent/severity of tissue damage and the microscopic disturbances. Beneficial effects in the therapy set-up were substantially higher and involved the inhibition of pro-inflammatory enzymes (iNOS, COX-2), cytokines (TNF-α, IL-1ß, and IL-6), as well as epithelial regeneration with restoration of goblet cells numbers and expression of MUC-2 and TFF-3. Consistently, LPS-induced RAW 264.7 cells produced less NO, PGE2, TNF-α, IL-6, and MCP-1. These effects might be related to the inhibition of the NF-κB signaling pathway. Our results suggest that sucrose esters from P. peruviana calyces, non-edible waste from fruit production, might be useful as an alternative IBD treatment.

WNT2B activates macrophages via NF-κB signaling pathway in inflammatory bowel disease.

Inflammation is a significant pathological manifestation of inflammatory bowel disease (IBD), yet its mechanism has remained unclear. Although WNT2B is enriched in the intestinal inflammatory tissue of IBD patients, the specific mechanism of WNT2B in the formation of intestinal inflammation remains unclear. This study was aimed to investigate whether macrophages expressing WNT2B can aggravate intestinal tissue inflammation. Samples were collected from both normal individuals and patients with IBD at multiple colon sites. Macrophages were identified using tissue immunofluorescence. IκB kinase (IKK)-interacting protein (IKIP), which interacts with WNT2B, was found by protein cross-linking and protein mass spectrometry. The expression of WNT2B, IKIP, the NF-κB pathway, and downstream molecules were analyzed. An acute colitis model of C57BL/6J mice was established using an adeno-associated virus (AAV)-mediated WNT2B knockdown system and 3% dextran sulfate sodium (DSS). The degree of intestinal inflammation in mice was assessed upon WNT2B knockdown in macrophages. Macrophages expressing WNT2B were found to be enriched in the colitis tissues of IBD patients. WNT2B in macrophages activated the NF-κB pathway and enhanced the expression of downstream inflammatory cytokines. By competitively binding IKIP, WNT2B reduced the binding of IKIP to IKKß and promoted the activation of the NF-κB pathway. Using an AAV-mediated WNT2B knockdown system, WNT2B expression in intestinal macrophages was suppressed, leading to a reduction in intestinal inflammation. WNT2B activated the NF-κB pathway and enhanced the expression of downstream inflammatory cytokines by competitively binding to IKIP, potentially contributing to colon inflammatory injury in IBD.

Indole-3-acetic acid alleviates DSS-induced colitis by promoting the production of R-equol from Bifidobacterium pseudolongum.

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by immune-mediated, chronic inflammation of the intestinal tract. The occurrence of IBD is driven by the complex interactions of multiple factors. The objective of this study was to evaluate the therapeutic effects of IAA in colitis. METHOD: C57/BL6 mice were administered 2.5% DSS in drinking water to induce colitis. IAA, Bifidobacterium pseudolongum, and R-equol were administered by oral gavage and fed a regular diet. The Disease Activity Index was used to evaluate disease activity. The degree of colitis was evaluated using histological morphology, RNA, and inflammation marker proteins. CD45+ CD4+ FOXP3+ Treg and CD45+ CD4+ IL17A+ Th17 cells were detected by flow cytometry. Analysis of the gut microbiome in fecal content was performed using 16S rRNA gene sequencing. Gut microbiome metabolites were analyzed using Untargeted Metabolomics. RESULT: In our study, we found IAA alleviates DSS-induced colitis in mice by altering the gut microbiome. The abundance of Bifidobacterium pseudolongum significantly increased in the IAA treatment group. Bifidobacterium pseudolongum ATCC25526 alleviates DSS-induced colitis by increasing the ratio of Foxp3+T cells in colon tissue. R-equol alleviates DSS-induced colitis by increasing Foxp3+T cells, which may be the mechanism by which ATCC25526 alleviates DSS-induced colitis in mice. CONCLUSION: Our study demonstrates that IAA, an indole derivative, alleviates DSS-induced colitis by promoting the production of Equol from Bifidobacterium pseudolongum, which provides new insights into gut homeostasis regulated by indole metabolites other than the classic AHR pathway.

Human umbilical cord/placenta mesenchymal stem cell conditioned medium attenuates intestinal fibrosis in vivo and in vitro.

BACKGROUND: A significant unmet need in inflammatory bowel disease is the lack of anti-fibrotic agents targeting intestinal fibrosis. This study aimed to investigate the anti-fibrogenic properties and mechanisms of the conditioned medium (CM) from human umbilical cord/placenta-derived mesenchymal stem cells (UC/PL-MSC-CM) in a murine intestinal fibrosis model and human primary intestinal myofibroblasts (HIMFs). METHODS: UC/PL-MSC-CM was concentrated 15-fold using a 3 kDa cut-off filter. C57BL/6 mice aged 7 weeks old were randomly assigned to one of four groups: (1) control, (2) dextran sulfate sodium (DSS), (3) DSS + CM (late-phase treatment), and (4) DSS + CM (early-phase treatment). Chronic DSS colitis and intestinal fibrosis was induced by three cycles of DSS administration. One DSS cycle consisted of 7 days of oral DSS administration (1.75%, 2%, and 2.5% DSS), followed by 14 days of drinking water. UC/PL-MSC-CM was intraperitoneally administered in the late phase (from day 50, 10 times) or early phase (from day 29, 10 times) of DSS cycles. HIMFs were treated with TGF-ß1 and co-treated with UC/PL-MSC-CM (10% of culture media) in the cellular model. RESULTS: In the animal study, UC/PL-MSC-CM reduced submucosa/muscularis propria thickness and collagen deposition, which improved intestinal fibrosis in chronic DSS colitis. The UC/PL-MSC-CM significantly reduced the expressions of procollagen1A1 and α-smooth muscle actin, which DSS significantly elevated. The anti-fibrogenic effect was more apparent in the UC-MSC-CM or early-phase treatment model. The UC/PL-MSC-CM reduced procollagen1A1, fibronectin, and α-smooth muscle actin expression in HIMFs in the cellular model. The UC/PL-MSC-CM downregulated fibrogenesis by suppressing RhoA, MRTF-A, and SRF expression. CONCLUSIONS: Human UC/PL-MSC-CM inhibits TGF-ß1-induced fibrogenic activation in HIMFs by blocking the Rho/MRTF/SRF pathway and chronic DSS colitis-induced intestinal fibrosis. Thus, it may be regarded as a novel candidate for stem cell-based therapy of intestinal fibrosis.

Sophoricoside improved Crohn's disease-like colitis by inhibiting intestinal epithelial cell apoptosis through PI3K/AKT signaling.

BACKGROUND AND AIMS: Increased apoptosis of intestinal epithelial cells (IECs) is a significant cause of intestinal barrier dysfunction in Crohn's disease (CD). Sophoricoside (SOP) is an isoflavone glycoside known for its anti-apoptotic properties. The aim of this study was to investigate the effects of SOP on mice with CD-like colitis and to understand the underlying mechanisms. METHODS: Mice treated with 2,4,6-trinitrobenzene sulfonic acid (TNBS) were used to examine the therapeutic effect of SOP on CD-like colitis and intestinal barrier damage. To further explore SOP's impact on IECs apoptosis and intestinal barrier protection, an in vitro colonic organoid apoptosis model induced by TNF-α was utilized. Network pharmacology was employed to predict the relevant pathways and molecular processes associated with SOP in the treatment of CD. RESULTS: Treatment with SOP significantly improved colitis symptoms in TNBS mice, as demonstrated by reductions in the Disease Activity Index (DAI), weight loss, colon shortening, macroscopic scores, colonic tissue inflammatory scores, and the expression of pro-inflammatory factors. Our experiments confirmed that SOP protects the intestinal barrier by counteracting IECs apoptosis. Additionally, this study established that SOP reduced IECs apoptosis by inhibiting the PI3K/AKT signaling pathway. CONCLUSIONS: SOP can reduce IECs apoptosis through the inhibition of the PI3K/AKT signaling pathway, thereby protecting the intestinal barrier. This study is the first to illustrate how SOP ameliorates colitis and protects the intestinal barrier, suggesting SOP has potential clinical application in treating CD.

Supplementation of citrus pectin with whole-cell pectinase PG5 on Pichia pastoris promotes recovery of colitis and enhances intestinal barrier function in DSS-treated mice.

A whole-cell biocatalyst was developed by genetically engineering pectinase PG5 onto the cell surface of Pichia pastoris using Gcw12 as the anchoring protein. Whole-cell PG5 eliminated the need for enzyme extraction and purification, while also exhibiting enhanced thermal stability, pH stability, and resistance to proteases in vitro compared to free PG5. Magnetic resonance mass spectrometry analysis revealed that whole-cell PG5 efficiently degraded citrus pectin, resulting in the production of a mixture of pectin oligosaccharides. The primary components of the mixture were trigalacturonic acid, followed by digalacturonic acid and tetragalacturonic acid. Supplementation of citrus pectin with whole-cell PG5 resulted in a more pronounced protective effect compared to free PG5 in alleviating colitis symptoms and promoting the integrity of the colonic epithelial barrier in a mouse model of dextran sulfate sodium-induced colitis. Hence, this study demonstrates the potential of utilizing whole-cell pectinase as an effective biocatalyst to promote intestinal homeostasis in vivo.

Targeted delivery of Fc-fused PD-L1 for effective management of acute and chronic colitis.

The PD-1/PD-L1 pathway in mucosal immunity is currently actively explored and considered as a target for inflammatory bowel disease (IBD) treatment. However, systemic PD-L1 administration may cause unpredictable adverse effects due to immunosuppression. Here we show that reactive oxygen species (ROS)-responsive nanoparticles enhance the efficacy and safety of PD-L1 in a mouse colitis model. The nanoparticles control the accumulation and release of PD-L1 fused to Fc (PD-L1-Fc) at inflammatory sites in the colon. The nanotherapeutics shows superiority in alleviating inflammatory symptoms over systemic PD-L1-Fc administration and mitigates the adverse effects of PD-L1-Fc administration. The nanoparticles-formulated PD-L1-Fc affects production of proinflammatory and anti-inflammatory cytokines, attenuates the infiltration of macrophages, neutrophils, and dendritic cells, increases the frequencies of Treg, Th1 and Tfh cells, reshapes the gut microbiota composition; and increases short-chain fatty acid production. In summary, PD-L1-Fc-decorated nanoparticles may provide an effective and safe strategy for the targeted treatment of IBD.

Combined administration of anisodamine and neostigmine alleviated colitis by inducing autophagy and inhibiting inflammation.

Our previous work demonstrated that the anisodamine (ANI) and neostigmine (NEO) combination produced an antiseptic shock effect and rescued acute lethal crush syndrome by activating the α7 nicotinic acetylcholine receptor (α7nAChR). This study documents the therapeutic effect and underlying mechanisms of the ANI/NEO combination in dextran sulfate sodium (DSS)-induced colitis. Treating mice with ANI and NEO at a ratio of 500:1 alleviated the DSS-induced colitis symptoms, reduced body weight loss, improved the disease activity index, enhanced colon length, and alleviated colon inflammation. The combination treatment also enhanced autophagy in the colon of mice with DSS-induced colitis and lipopolysaccharide/DSS-stimulated Caco-2 cells. Besides, the ANI/NEO treatment significantly reduced INF-γ, TNF-α, IL-6, and IL-22 expression in colon tissues and decreased TNF-α, IL-1ß, and IL-6 mRNA levels in Caco-2 cells. Meanwhile, the autophagy inhibitor 3-methyladenine and ATG5 siRNA attenuated these effects. Furthermore, 3-methyladenine (3-MA) and the α7nAChR antagonist methyllycaconitine (MLA) weakened the ANI/NEO-induced protection on DSS-induced colitis in mice. Overall, these results indicate that the ANI/NEO combination exerts therapeutic effects through autophagy and α7nAChR in a DSS-induced colitis mouse model.