Immunological pathogenesis of inflammatory bowel disease

The gut-skin axis: a bi-directional, microbiota-driven relationship with therapeutic potential

This review explores the emerging term "gut-skin axis" (GSA), describing the bidirectional signaling that occurs between the skin and the gastrointestinal tract under both homeostatic and disease conditions. Central to GSA communication are the gut and skin microbiota, the microbial communities that colonize these barrier surfaces. By influencing diverse host pathways, including innate immune, vitamin D receptor, and Aryl hydrocarbon receptor signaling, a balanced microbiota contributes to both tissue homeostasis and host defense. In contrast, microbiota imbalance, or dysbiosis at one site, can lead to local barrier dysfunction, resulting in the activation of signaling pathways that can disrupt tissue homeostasis at the other site, potentially leading to inflammatory skin conditions such as atopic dermatitis and psoriasis, or gut diseases like Inflammatory Bowel Disease. To date, most research on the GSA has examined the impact of the gut microbiota and diet on skin health, but recent studies show that exposing the skin to ultraviolet B-light can beneficially modulate both the gut microbiome and intestinal health. Thus, despite the traditional focus of clinicians and researchers on these organ systems as distinct, the GSA offers new opportunities to better understand the pathogenesis of cutaneous and gastrointestinal diseases and promote health at both sites.

A systematic review on the role of gut microbiome in inflammatory bowel disease: Spotlight on virome and plant metabolites

Inflammatory bowel diseases (IBD), including ulcerative colitis and Crohn's disease, arise from various factors such as dietary, genetic, immunological, and microbiological influences. The gut microbiota plays a crucial role in the development and treatment of IBD, though the exact mechanisms remain uncertain. Current research has yet to definitively establish the beneficial effects of the microbiome on IBD. Bacteria and viruses (both prokaryotic and eukaryotic) are key components of the microbiome uniquely related to IBD. Numerous studies suggest that dysbiosis of the microbiota, including bacteria, viruses, and bacteriophages, contributes to IBD pathogenesis. Conversely, some research indicates that bacteria and bacteriophages may positively impact IBD outcomes. Additionally, plant metabolites play a crucial role in alleviating IBD due to their anti-inflammatory and microbiome-modulating properties. This systematic review discusses the role of the microbiome in IBD pathogenesis and evaluates the potential connection between plant metabolites and the microbiome in the context of IBD pathophysiology.

Ginsenoside Rg1 alleviated experimental colitis in obesity mice by regulating memory follicular T cells via Bcl-6/Blimp-1 pathway

The pathological mechanisms of ulcerative colitis (UC) are closely related with abnormal memory follicular helper T (mTfh) cell subsets and the Bcl-6/Blimp-1 signaling pathway. Ginsenoside Rg1 (G-Rg1) has been confirmed to exhibit therapeutic effects in obese mice with dextran sulfate sodium (DSS)-induced ulcerative colitis. The aim of this study was to investigate the mechanism of action of G-Rg1 in obese mice with UC by observing mTfh cell subsets and the Bcl-6/Blimp-1 signaling pathway. Obese mice with UC were treated with G-Rg1 at a dose of 200 mg/kg. Disease activity was assessed macroscopically and microscopically, and cytokine levels were measured using enzyme-linked immunosorbent assay (ELISA). Flow cytometry was employed to analyze mTfh cell subsets, and Western blotting to assess protein expression related to the Bcl-6/Blimp-1 pathway. qPCR was used to detect the expression of Bcl-6/Blimp-1, and immunofluorescence was utilized to compare Bcl-6/Blimp-1 expression between different groups. G-Rg1 treatment ameliorated the symptoms of DSS-induced colitis, alleviated the pathological changes in the colonic tissue of obese mice with ulcerative colitis, and reduced the levels of inflammatory cytokines in these mice. Furthermore, flow cytometry analysis indicated that G-Rg1 modulated the balanceof mTfh cells subsets by increasing central memory Tfh (cmTfh) cells and decreasing effector memory Tfh (emTfh) cells, thereby mitigating ulcerative colitis in obese mice. qPCR results revealed the significant upregulation of Bcl-6 and the downregulation of Blimp-1 expression in the DSS group, which was effectively reversed by G-Rg1 treatment. These findings were further confirmed by Western blot and immunofluorescence assays. Collectively, the qPCR, Western blot, and immunofluorescence results demonstrated the pivotal role of the Bcl-6/Blimp-1 signaling pathway in the therapeutic process of G-Rg1 for ulcerative colitis in obese mice. Ginsenoside Rg1 alleviates experimental colitis in obese mice by modulating the proportion of mTfh cell subsets via the Bcl-6/Blimp-1 signaling pathway.

Chlorpyrifos Inhibits Intestinal Stem Cell Proliferation and Differentiation at the Acceptable Daily Intake and Disrupts Immune Responses at High Doses

The acceptable daily intake (ADI) and maximum residue limits in food for chlorpyrifos (CPF), a widely used organophosphorus pesticide, may damage the intestine. Here, we evaluated damage to the intestine by CPF at the ADI (0.01 mg/kg bodyweight/day) and at 10 times the ADI (10ADI; 0.1 mg/kg bodyweight/day) in mice after 8 weeks of exposure and evaluated the resulting immune response to an enterotoxigenic Escherichia coli (ETEC) infection. CPF at the ADI dose significantly disrupted the intestinal integrity and intestinal stem cell functionality, which may be associated with reduced indole-3-propionic acid levels. However, mice in the 10ADI group exhibited only elevated pro-inflammatory cell and cytokine levels. During ETEC infection, intestinal mucosal immunity was activated by the 10ADI dose, as indicated by increased regulatory T cells and IL-10 levels, which were associated with decreased fecal butyric acid content. Our study demonstrated that the effects of pesticide residues appear to be dose-specific, bringing attention to the health risk at the ADI level.

Anti-inflammatory effects and gut microbiota modulation of synbiotic mulberry in DSS-induced colitis rats

The global incident shows that the number of inflammatory bowel disease (IBD) cases increased by 88.30% in 2021 and significantly influenced patients' quality of life. Synbiotics are recommended as an alternative or supplement for IBD. We formulated synbiotic mulberry (SM) by mixing mulberry powder, probiotic biomass, and inulin. However, the anti-inflammatory effect of SM and gut microbiota modulation in dextran-sodium-sulfate (DSS)-induced colitis rats has not been thoroughly investigated. Thus, the anti-inflammatory activity of SM and gut microbiota composition was explored using DSS-induced acute colitis rats. Rats were divided into seven groups: control, control+SM1000, DSS, DSS+SM250, DSS+SM500, DSS+SM1000, and DSS+Sulfazalazine (SUL). All DSS induction rats received dissolving 4% (w/v) DSS in drinking water for 7 days, and their respective treatment was once daily via oral gavage. In addition, DSS-aggravated colitis rats received 0.4% (w/v) DSS in drinking water and their respective treatments once daily for the next 7 days. SM improved the disease activity index (DAI), body weight (BW), hepatosplenomegaly, colon length, and colon histomorphology, with outcomes similar to the results of SUL administration. Furthermore, SM decreased the levels of IL-6 production and suppressed iNOS and IL-10 mRNA expression in the colon. SM induced significant modulation in gut microbiota by significantly increasing the abundance of Allobaculu. SM also affects the amount of metabolic enzyme classes. In conclusion, we propose that SM may hold promise as a functional food therapeutic approach for the treatment of colitis; however, additional clinical trials are considered necessary to confirm these effects.

Prevalence and clinical characteristics of children with coexisting coeliac disease and inflammatory bowel disease

OBJECTIVE

Growing evidence suggests that coeliac disease (CeD) is more common in patients with inflammatory bowel disease (IBD) but diagnostic confusion remains due to overlapping histological and clinical features. Few studies have investigated this relationship in children. We aimed to assess the prevalence of CeD in our paediatric IBD cohort and define the characteristics of IBD when CeD coexists.

METHODS

We conducted a retrospective study of all patients <18 years old diagnosed with IBD in Southampton Children's Hospital between January 2019 and December 2023. Patients were identified using our IBD database, and data were collected on diagnosis, endoscopy, histopathology, serology, IBD treatment and surgery using electronic patient records.

RESULTS

18 of the 479 children with IBD were also diagnosed with CeD (3.75%). 14 underwent duodenal biopsy on gluten, with 13 fulfilling Marsh classification 2-3. Eight children had Crohn's disease, five had ulcerative colitis and five had IBD-unclassified. 16 out of 18 demonstrated colonic disease; 11 out of 18 had pancolitis. There was no significant difference in the rate of biological therapy use between the IBD-CeD and non-coeliac groups (50% vs 68%). No patients with IBD-CeD underwent IBD surgery.

CONCLUSIONS

1 in 25 children with IBD had coexisting CeD. Pancolitis was the most prominent IBD phenotype but a diagnosis of CeD was not associated with increased escalation to biological therapy, and no patients required surgery. These findings help to describe the paediatric IBD-coeliac phenotype and demonstrate the importance of considering IBD in children with refractory CeD and screening for CeD in children presenting with IBD.

Immune modulation for the patterns of epithelial cell death in inflammatory bowel disease

Inflammatory bowel disease (IBD) is an inflammatory disease of the intestine whose primary pathological presentation is the destruction of the intestinal epithelium. The intestinal epithelium, located between the lumen and lamina propria, transmits luminal microbial signals to the immune cells in the lamina propria, which also modulate the intestinal epithelium. In IBD patients, intestinal epithelial cells (IECs) die dysfunction and the mucosal barrier is disrupted, leading to the recruitment of immune cells and the release of cytokines. In this review, we describe the structure and functions of the intestinal epithelium and mucosal barrier in the physiological state and under IBD conditions, as well as the patterns of epithelial cell death and how immune cells modulate the intestinal epithelium providing a reference for clinical research and drug development of IBD. In addition, according to the targeting of epithelial apoptosis and necroptotic pathways and the regulation of immune cells, we summarized some new methods for the treatment of IBD, such as necroptosis inhibitors, microbiome regulation, which provide potential ideas for the treatment of IBD. This review also describes the potential for integrating AI-driven approaches into innovation in IBD treatments.

From traditional to artificial intelligence-driven approaches: Revolutionizing personalized and precision nutrition in inflammatory bowel disease

Inflammatory bowel disease (IBD), comprising ulcerative colitis and Crohn's disease, is a chronic inflammatory condition with global prevalence and varying incidence. The IBD pathogenesis involves intricate interactions among genetic, host and environmental factors, leading to dysregulated immune responses and chronic intestinal inflammation. Alongside elevated levels of inflammatory cytokines and altered miRNAs expression, more studies highlight significant dysbiosis in both fecal and ileal microbiota of IBD patients. This dysbiosis is characterized by an increase in pro-inflammatory and mucin-degrading bacteria (e.g., Fusobacterium spp., Escherichia spp.) and a decline in short-chain fatty acids (SCFAs) -producing microbes (e.g., Roseburia spp., Faecalibacterium spp.) which play a protective role in gut health. Diet emerges as a key environmental factor influencing IBD onset and progression and recent advancements in"omics" technologies, such as genomics, transcriptomics, and metabolomics, provide a deeper understanding of the molecular interactions between genes, gut microbiota (GM) and nutrition. Finally, new technologies like artificial intelligence (AI), further enhance findings by enabling data integration and personalized dietary strategies. In this scenario, this review aims to summarize accumulating data on the effects of dietary interventions in IBD patients and introduce the role of artificial intelligence (AI) in facilitating precision dietary approaches to improve IBD management.

Anti-inflammatory agents design via the fragment hybrid strategy in the discovery of compound c1 for treating ALI and UC

Acute lung injury (ALI) and ulcerative colitis (UC) are common inflammatory diseases with high mortality rates and unsatisfactory cure rates. Studies have indicated that inhibiting the expression and release of inflammatory factors holds potential for the treatment of inflammatory diseases. In this study, we designed and synthesized 28 derivatives of 6,7-disubstituted-4-cis-cyclohexanequinazoline and assessed their anti-inflammatory activities in mouse macrophages RAW264.7, J774A.1, and human monocyte THP-1 cell lines. Among them, derivative c1 was found to significantly inhibit the expression and release of pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) induced by lipopolysaccharide (LPS) in the three cells mentioned above. It was also demonstrated that c1 could bind to IRAK4 and affect the expression of these two inflammatory factors by inhibiting the activation of the MAPK pathway. Furthermore, in vivo experiments revealed that c1 effectively ameliorated LPS-induced ALI and dextran sulfate sodium (DSS)-induced UC. Additionally, we evaluated the pharmacokinetic properties and in vivo safety of c1. Therefore, our research has identified the 6,7-disubstituted-4-cis-cyclohexanequinazoline derivative c1 exhibiting promising anti-inflammatory effects as a prospective anti-inflammatory drug candidate.

Comprehensive computational strategies for multi-target drug discovery in inflammatory bowel disease utilizing bioactive compounds

Inflammatory bowel disease (IBD) is a chronic gastrointestinal condition that encompasses ulcerative colitis (UC) and Crohn's disease (CD). Targeting both inflammation and the epithelial barrier simultaneously can significantly improve symptom management in IBD, as a promising strategy. In this study, we focused on addressing both inflammation and the epithelial barrier. Until now, each therapeutic target including phosphodiesterase 4 (PDE4) and prolyl hydroxylase domain enzymes 1 and 2 (PHD1/2) have been studied separately. PDE4 plays a key role in the inflammatory process by converting cyclic AMP (cAMP) to AMP and its inhibition can suppress the production of inflammatory cytokines. Research has shown that inhibiting PHD1 and PHD2 increases levels of hypoxia-inducible factor-alpha (HIF-α), which in turn strengthens the epithelial barrier by promoting the expression of protective factors such as mucins and β-defensins. Through virtual screening, molecular docking, and molecular dynamics simulations, we identified five compounds-Cassiamin C, Ginkgetin, Hinokiflavone, Sciadopitysin, and Sojagol-as promising new drug candidates for IBD treatment. All compounds demonstrated superior free binding energy for the three targets compared to reference ligands, except Sojagol concerning PDE4B. Among these compounds, Ginkgetin was the best compound with potential ability of targeting multiple drug target proteins. Future experimental studies are warranted to validate these findings.

Predictors of Immunogenicity and Loss of Response to ANTI-TNFα Therapy in Crohn Disease-A Systematic Review

BACKGROUND

As the use of anti-tumor necrosis factor-α (TNFα) therapies in Crohn disease (CD) is spread, the loss-of-response (LOR) to it is increasingly encountered. Discovering a pathological pathway and biomarkers that can predict LOR would assist in the management of patients with CD. In this article, we provide a comprehensive systematic review of studies assessing predictors of immunogenicity and loss-of-response to anti-TNFα drugs in patients with CD.

DATA SOURCES

We performed a systematic review of PubMed to identify citations pertaining to predictors of immunogenicity and loss-of-response to anti-TNFα drugs in patients with CD through April 27, 2024, using a predefined string of keywords. Data extraction and quality assessment were performed independently by 2 reviewers.

RESULTS

A total of 18 eligible studies were included in the review. Four major groups of studies were identified: genetic factors, factors linked with colonic inflammation, serum and anthropological markers, and prevention of LOR. Promising predictors of LOR to infliximab or adalimumab include the carriage of HLA-DQA1*05, visceral adiposity, intestinal abundant presence of CD96, IL-17, and IL-23. Substantial heterogeneity was observed, and none of the markers had undergone formal validation. Specific limitations to acceptance of these factors included failure to use a standardized definition of LOR to anti-TNFα treatment, lack of specificity, and insufficient relevance to the pathogenesis of LOR.

CONCLUSIONS

This review underlines the lack of well-defined studies and controlled trials investigating predictors of LOR to anti-TNFα therapies in CD. A research priority is the development of reliable and accurate biomarkers that can shed light on the pathogenesis of the implied LOR. These biomarkers, along with genetic factors, have the potential to enhance clinical management by aiding in patient stratification and monitoring.

Particulate matter-shaped Th17 cell plasticity impairs the colonic mucus layer

The intestine is one of the target organs upon ambient particulate matter (PM) exposure. However, the mechanism underlying PM-induced colonic injury remains unexplained. The present study emphasizes the significance of adaptive T cells crossing circulation-intestine signaling during PM exposure. To investigate this, mononuclear cells in circulation and intestine were isolated and exposed to PM ex vivo. We found that the PM-induced peripheral inflammatory microenvironment promoted inflammatory polarization of T helper 17 (Th17) cells in circulation and intestine in sequence. Further animal models and the Th17 cell adoptive transfer model showed that PM exposure induced the loss of colonic mucus through priming inflammatory Th17 cells in vivo. Mechanistically, PM exposure activated aryl hydrocarbon receptor (AhR) signaling and transcriptionally induced retinoic acid receptor-related orphan receptor C (RORC) expression in circulation Th17 cells, subsequently activating and polarizing colonic Th17 cells, ultimately resulting in the loss of colonic mucus. Moreover, Interleukin (IL)-6 knockout resisted PM exposure-induced colonic injury via inhibiting differentiation of Th17 cells. To conclude, the study results provide clarification on the processes of PM-related immunology response in the colon and the mechanism aiding the development of novel intervention strategies to maintain homeostasis in the colon.

Resveratrol targeting MDM2/P53/PUMA axis to inhibit colonocyte apoptosis in DSS-induced ulcerative colitis mice

Background

Resveratrol, a naturally occurring polyphenolic compound found in grapes, berries, and traditional medicinal plants like Polygonum cuspidatum, has been used for centuries in traditional medicine systems for its anti-inflammatory, antioxidant, and cardioprotective properties. Ulcerative colitis (UC), a chronic inflammatory bowel disease, is characterized by intestinal barrier disruption due to excessive colonocyte apoptosis, leading to increased permeability and inflammation. Targeting apoptosis is a critical therapeutic strategy for UC.

Aim of the study

This study aims to investigate the therapeutic potential of Resveratrol in ulcerative colitis (UC) by targeting excessive colonocyte apoptosis and intestinal barrier dysfunction. Specifically, we seek to elucidate the mechanisms through which Resveratrol modulates apoptosis-related pathways and evaluate its efficacy in restoring intestinal homeostasis and mitigating UC progression in both in vivo and in vitro models.

Materials and Methods

We used dextran sulfate sodium (DSS) to induce UC in a mouse model. Colonic damage was assessed through colonic length measurement, histological examination, and immunofluorescence staining. Single-cell sequencing was employed to explore changes in the colonic immune microenvironment and cellular signaling pathways after Resveratrol treatment. In vitro, colonocytes isolated from healthy mouse colonic tissue were exposed to TGF-β to induce apoptosis. DNA fragmentation, mitochondrial membrane potential, and annexin V/propidium iodide staining were used to assess apoptosis. Additionally, we employed an Adeno-Associated Virus system to overexpress MDM2 in the colon and evaluate its protective role in DSS-induced UC.

Results

Resveratrol treatment effectively repaired colonic damage in the UC mouse model by significantly increasing colon length, reducing inflammatory cell infiltration, and mitigating mucosal injury. Single-cell sequencing revealed that Resveratrol primarily targeted colonocytes, decreasing genes related to apoptosis and the P53 pathway. In vitro, Resveratrol reduced DNA fragmentation, apoptotic cell populations, and increased mitochondrial membrane potential in a dose-dependent manner. Furthermore, Resveratrol increased MDM2 expression, inhibiting P53 and downstream pro-apoptotic signaling. Nutlin-3a, an MDM2 inhibitor, reversed the anti-apoptotic effects of Resveratrol. Overexpression of MDM2 in the colon protected against DSS-induced damage.

Conclusion

Resveratrol is an effective treatment for DSS-induced UC, primarily by inhibiting excessive apoptosis in colonocytes through the MDM2/P53/PUMA axis. MDM2 presents a promising therapeutic target for UC treatment.

Glycyrrhiza uralensis extract supplementation mitigated the negative effects of prolonged low-dose exposure to Deoxynivalenol and Zearalenone on growth performance and intestinal health of broiler chickens

Deoxynivalenol (DON) and Zearalenone (ZEN), common symbiotic mycotoxins found in mold-contaminated cereal feed, adversely affect broiler' health. Glycyrrhiza uralensis has various pharmacological effects including antibacterial, antioxidant and immunomodulatory. This study aimed to investigate the effects of the long-term intake of low doses of DON and ZEN on growth performance and intestinal health of broilers, as well as the potential protective effect of supplementary Glycyrrhiza uralensis extract (GUE) in an 84-day feeding experiment. A total of 315 one-day-old male Liangfeng broilers were randomly assigned to three treatments: basal diet (CON), MOL diet (where 5% of corn in the basal diet was replaced with an equal amount of naturally moldy corn) containing DON and ZEN at 1.25 and 1.29 mg/kg, and MGUE diet supplemented with 0.1% GUE in the MOL diet. The MOL diet reduced the body weight (BW) of broilers at 56 and 84 day, body weight gain (BWG) and feed intake (FI) aged 1-56 and 1-84 days, and the feed conversion ratio (FCR) aged 1-84 days, as well as villus height (VH) and the villus/crypt (V/C) ratio, SOD and GSH-Px activities, and the expression of claudin-1, occludin and ZO-1, while increasing MDA level, the expression of TNF-α, IL-1β and IFN-γ in the jejunum of broilers. Additionally, MOL diet decreased the Firmicutes to Bacteroidetes (F/B) ratio and abundances of Lactobacillus (L.gallinarum and L.crispatus), and B.vulgatus, while increasing Bacteroides (B.fragilis and B.dore), Helicobacter (H.pullorum), and Escherichia (E.coli) in the ceca. In contrast, MGUE diet improved growth performance and returned it to a level comparable to that of the CON diet, increased VH and V/C ratio, SOD and GSH-Px activity, claudin-1, occludin and ZO-1 expression, while reducing MDA level, the expression of TNF-α, IL-1β and IFN-γ in the jejunum. Moreover, MGUE diet had a greater F/B ratio and abundance of Lactobacillus (L.gallinarum and L.crispatus) and B.vulgatus, while reducing Bacteroides (B.fragilis and B.dorei), Helicobacter (H.pullorum) and Escherichia (E.coli) in cecum. In conclusion, the long-term consumption of a low-dose DON-ZEN contaminated diet decreases growth performance and disrupts intestinal health and microbiota balance in broilers; however, dietary supplementation with GUE effectively mitigates the damage caused by DON-ZEN contamination.

Biosimilars versus biological therapy in inflammatory bowel disease: challenges and targeting strategies using drug delivery systems

Inflammatory bowel disease (IBD) is a multifactorial illness with a climbing prevalence worldwide. While biologics are commonly prescribed especially for severe cases, they may worsen patients' outcomes due to financial burden. Consequently, there has been an increased focus on biosimilars to improve overall disease outcomes by maintaining similar efficacy and safety while minimizing the cost of therapy. Infliximab-dyyb was the first biosimilar approved by US-FDA for IBD. Since that, the US-FDA approved 14 biosimilars with different mechanisms of action and different routes of administration for IBD patients (four infliximab biosimilars, nine adalimumab biosimilars, and most recently one ustekinumab biosimilar). It should be noted that more biologics are in the pipeline as golimumab and natalizumab patents are set to expire in the near future, and biosimilars are now in pre-clinical to phase 3 trials. Different studies have evaluated biologics' effectiveness and safety and concluded that the majority of available biosimilars are efficacious and have similar adverse effect profiles compared to their reference biologics. It is worth mentioningthat post-marketing surveillance reports revealed some risks associated with biosimilars which should be taken into consideration in future research and clinical trials to avoid health hazards. Most biologics and biosimilars are administered parenterally which results in several drawbacks such as raised risk of infections, hypersensitivity, autoimmunity, development of malignancies, liver toxicity as well as worsening of heart failure. Several drug delivery systems based on passive and active targeting mechanisms are under active investigation to overcome these limitations. This review sheds light on the emergence of biologics and biosimilars as alternatives in IBD management, the differences between them, challenges and risks, and future perspectives in IBD therapy and new trends in drug delivery systems.

Bone Broth Benefits: How Its Nutrients Fortify Gut Barrier in Health and Disease

Bone broth is a traditional nutrient revered by different people from ancient times to the modern era as a remedy for various illnesses. This review investigates the nutritional components of bone broth, focusing primarily on the most abundant amino acids and minerals saturated in bone broth and their impact on health, particularly in the context of intestinal barrier integrity, intestinal permeability, inflammation, and their application in inflammatory bowel disease. Through comprehensive reviews of animal and human studies, this research highlights that bone broth includes amino acids (glutamine, glycine, proline, histidine, arginine), minerals (Ca, P, K, Mg, Zn) that are beneficial and not just a traditional remedy, resolving questions that have been posed for generations. The benefits documented for components in bone broth support the enhancement of gut health, alleviate inflammation in the intestinal barrier, improve intestinal barrier function in health and disease states, particularly in inflammatory bowel disease, as well as enhancing nutrient absorption. Bone broth offers a nutrient-dense option for enhancing overall health and may offer an alternative to dietary supplements with claims for enhanced gut health. We aim to foster interest in and provide evidence to substantiate claims for bone broth as a potential remedy, particularly for maintaining remission in conditions like IBD and possibly functional diarrhea and to encourage further research.

Immunomodulatory effects and clinical application of exosomes derived from mesenchymal stem cells

Exosomes (Exos) are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication. They play a pivotal role in the pathogenesis and progression of various diseases and offer promising avenues for therapeutic interventions. Exos derived from mesenchymal stem cells (MSCs) have significant immunomodulatory properties. They effectively regulate immune responses by modulating both innate and adaptive immunity. These Exos can inhibit excessive inflammatory responses and promote tissue repair. Moreover, they participate in antigen presentation, which is essential for activating immune responses. The cargo of these Exos, including ligands, proteins, and microRNAs, can suppress T cell activity or enhance the population of immunosuppressive cells to dampen the immune response. By inhibiting lymphocyte proliferation, acting on macrophages, and increasing the population of regulatory T cells, these Exos contribute to maintaining immune and metabolic homeostasis. Furthermore, they can activate immune-related signaling pathways or serve as vehicles to deliver microRNAs and other bioactive substances to target tumor cells, which holds potential for immunotherapy applications. Given the immense therapeutic potential of MSC-derived Exos, this review comprehensively explores their mechanisms of immune regulation and therapeutic applications in areas such as infection control, tumor suppression, and autoimmune disease management. This article aims to provide valuable insights into the mechanisms behind the actions of MSC-derived Exos, offering theoretical references for their future clinical utilization as cell-free drug preparations.

Serum Maresin-1 and Resolvin-D1 Levels as Non-Invasive Biomarkers for Monitoring Disease Activity in Ulcerative Colitis

Background: Specialized pro-resolving lipid mediators (SPMs), such as maresins and resolvins, play a key role in resolving inflammation and repairing tissues. This study aimed to evaluate whether maresin-1 (MaR1) and resolvin-D1 (RvD1) could serve as serum non-invasive biomarkers for monitoring disease activity in ulcerative colitis (UC). Methods: This cross-sectional study included 60 UC patients (30 active, 30 remission) and 30 healthy controls. Disease activity was assessed using the Mayo Endoscopic Subscore (MES). Inflammatory indices, including the neutrophil-lymphocyte ratio (NLR), monocyte-HDL cholesterol ratio (MHR), platelet-lymphocyte ratio (PLR), CRP-lymphocyte ratio (CLR), CRP-albumin ratio (CAR), systemic inflammation response index (SIRI), and systemic immune-inflammation index (SII), were calculated. Plasma MaR1 and RvD1 levels were measured via enzyme-linked immunosorbent assay (ELISA). Receiver operating characteristic (ROC) analysis was performed to evaluate biomarker accuracy. Results: CRP, NLR, PLR, CLR, CAR, SIRI, and SII were significantly elevated in active UC, whereas MaR1 and RvD1 were lower compared to remission and controls (p < 0.05). MaR1 levels were lower in the remission group than in controls. ROC analysis demonstrated high area under the curve (AUC) values for RvD1 (0.906), CAR (0.872), CLR (0.861), and CRP (0.858) in distinguishing active UC from remission, and for CRP (0.944), CAR (0.939), CLR (0.939), RvD1 (0.928), and MaR1 (0.889) in distinguishing active UC from controls. The specificity for detecting active UC was 60% for MaR1 and 80% for RvD1. Both RvD1 and MaR1 showed a negative correlation with the MES, with RvD1 demonstrating a stronger correlation (r = -0.754, p < 0.001). Conclusions: RvD1 shows a strong negative correlation with disease severity in ulcerative colitis, while low MaR1 levels in remission may indicate subclinical inflammation. Although MaR1 and RvD1 are not disease-specific, their role in inflammation resolution suggests they may complement conventional inflammatory markers for more comprehensive UC monitoring.

Cholesteryl Ester Species but Not Serum Proprotein Convertase Subtilisin/Kexin Type 9 Levels Decline in Male Patients with Active Inflammatory Bowel Disease

BACKGROUND/OBJECTIVES

Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates serum cholesterol levels and inflammation, both of which are dysregulated in inflammatory bowel disease (IBD). Free cholesterol (FC) and the various types of cholesteryl ester (CE) have different functions in the body. However, it is not yet known whether these lipids undergo parallel changes in male and female patients with active IBD, nor whether PCSK9 correlates with these lipids and disease severity in either sex. The present study measured the serum levels of PCSK9, FC, and 15 CE species in IBD patients, focusing on the associations of these molecules with sex, each other, and with disease severity.

METHODS

The serum PCSK9 levels of 80 IBD patients (42 males and 38 females) and 24 controls (12 males and 12 females) were measured by enzyme-linked immunosorbent assay. In addition, FC and 15 CE species levels of 53 randomly selected IBD patients and 16 controls were determined by direct flow injection analysis (FIA) using a high-resolution hybrid quadrupole-orbitrap mass spectrometer (FIA-FTMS).

RESULTS

Serum PCSK9 levels in controls and IBD patients were comparable and did not correlate with disease severity in IBD patients. There was no discernible difference in serum PCSK9, FC, and CE levels between patients with Crohn's disease (CD) and those with ulcerative colitis (UC). FC and almost all CE species decreased in male patients with active IBD but were not related to disease severity in the female patients. The decrease in different CE species in male IBD patients with diarrhea compared to those with normal stool consistency appears to be related to IBD severity. Bile acids regulate serum cholesterol levels, and FC and CE levels were positively correlated with fecal levels of secondary bile acids in the patients with UC but not CD. This association also existed in male UC patients and could not be evaluated in women due to the small sample size.

CONCLUSIONS

In active IBD, a reduction in FC and almost all CE species was observed only in males, while serum PCSK9 levels remained within normal ranges in both sexes. It can be hypothesized that blocking PCSK9 may further reduce serum cholesterol levels, which may have adverse effects in male patients with active IBD.

Unleashing the potential of extracellular vesicles for ulcerative colitis and Crohn's disease therapy

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Macadamia oil alleviates dextran sulfate sodium-induced ulcerative colitis in mice via activating the Nrf2/Ho-1 pathway

Macadamia nut oil (MO) fatty acids are mainly composed of oleic acid and palmitoleic acid, which have a variety of health benefits. This study established an ulcerative colitis (UC) mouse model using dextran sulfate sodium (DSS), and the ameliorative effects of MO on UC were investigated. The results revealed that MO supplementation mitigated weight loss and colon shortening, increased goblet cell counts, and alleviated histopathologic changes in UC mice. MO significantly increased the intestinal antioxidant levels in UC mice. Moreover, Nrf2 and Ho-1 mRNA and protein expression levels were significantly upregulated in UC mice following treatment with low- and high-dose MO. In contrast, expression levels of Keap1 were significantly downregulated. Lastly, MO inhibited the inflammatory factors (TNF-α, IL-6 and IL-1β) expression in UC mice. These results indicate that MO could enhance colonic antioxidant levels, induce apoptosis, and activate the Nrf2/Ho-1 pathway, thereby ameliorating the pathological injuries associated with UC.

Exploring the potential active components and mechanisms of Tetrastigma hemsleyanum against ulcerative colitis based on network pharmacology in LPS-induced RAW264.7 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a chronic form of inflammatory bowel disease, which current treatments often show limited effectiveness. Ferroptosis, a newly recognized form of programmed cell death has been implicated in UC pathogenesis, suggesting that it may be viable therapeutic target. Tetrastigma hemsleyanum (TH) has shown potential anti-UC effects, though it is unclear whether its therapeutic benefits are mediated by ferroptosis.

AIM OF THE STUDY

This study investigated the involvement of ferroptosis in the therapeutic effects of TH and identified key active components and pathways of TH against UC.

MATERIALS AND METHODS

The ethyl acetate extract of TH (TH_E) was found to be the most effective anti-inflammatory extract compared with the petroleum ether extract (TH_P), n-butanol extract (TH_N), and water-soluble extract (TH_W). TH_E's components were identified using UHPLC-MS/MS, ADME parameters, and network pharmacology. Additionally, TH_E's effects on ferroptosis were evaluated in an LPS-induced RAW264.7 cell model.

RESULTS

TH_E exhibited the strongest anti-inflammatory activity among four extracts. 10 compounds (Linolenic acid; Apigenin; Protocatechualdehyde; Asiatic acid; Quercetin; Isorhamnetin; Kaempferol; Azelaic acid; Oleic Acid; Palmitic acid) were selected from SwissADME database. Then a total of 281 targets for these 10 compounds and 1330 UC-related targets were identified from different database. Isorhamnetin was selected as the most promising anti-inflammatory component among 10 components. Furthermore, enrichment analysis revealed that ferroptosis was involved in UC development, with both TH_E and isorhamnetin exhibited inhibition of ferroptosis. Finally, isorhamnetin's anti-ferroptosis effects were linked to the Keap1/Nrf2/HO-1 pathway.

CONCLUSIONS

The results demonstrate that TH_E and isorhamnetin alleviate LPS-induced UC through restraining ferroptosis. Moreover, isorhamnetin's anti-UC properties are mediated by inhibiting ferroptosis via activation of the Keap1/Nrf2/HO-1 axis.

Targeting gut microbiota dysbiosis in inflammatory bowel disease: a systematic review of current evidence

Introduction

The dysbiosis of the gut microbiota has been identified as a central factor in the pathogenesis of inflammatory bowel disease (IBD), a chronic condition characterized by frequent recurrence and various adverse effects of traditional therapies. While treatments targeting the gut microbiota show promise, their efficacy in IBD management still requires extensive evaluation. Our systematic review analyzes recent studies to elucidate the advancements and challenges in treating IBD using microbial-based therapies.

Methods

Through a comprehensive systematic review spanning key scientific databases-PubMed, Embase, Cochrane, Web of Science, Scopus, and Google Scholar-we scrutinized the impact of probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) on individuals with IBD. Our detailed analysis covered study and participant demographics, along with seven key outcome measures: disease activity index, inflammatory markers, serum cytokines, microbiome composition, adverse effects, and the rates of remission and relapse.

Results

From 6,080 initial search hits, we included 71 studies that assessed various interventions compared to placebo or standard medical therapy. Although there was notable variation in clinical results while assessing different outcomes, overall, probiotics, prebiotics, and synbiotics enhanced the success rates in inducing remission among IBD patients. Furthermore, we noted significant reductions in levels of pro-inflammatory markers and cytokines. Additionally, the requirement for steroids, hospitalization, and poor outcomes in endoscopic and histological scores were significantly reduced in individuals undergoing FMT.

Conclusion

Our investigation highlights the potential of targeting gut microbiota dysbiosis with microbial-based therapies in patients with IBD. We recommend conducting larger, placebo-controlled randomized trials with extended follow-up periods to thoroughly assess these treatments' clinical efficacy and safety before widespread recommendations for clinical application.

The role of efferocytosis in inflammatory bowel disease

Efferocytosis is the process by which various phagocytes clear apoptotic cells. In recent years, an increasing body of evidence has emphasized the importance of efferocytosis in maintaining internal homeostasis. Intestinal macrophages play a crucial role in modulating intestinal inflammation and promoting tissue repair. Inflammatory bowel disease (IBD) is a chronic, progressive, and relapsing condition, primarily marked by the presence of ulcers in the digestive tract. The exact mechanisms underlying IBD are not yet fully understood, and current treatment approaches mainly aim at repairing the damaged intestinal mucosa and reducing inflammatory responses to ease symptoms.This article provides new perspectives on IBD treatment and clinical management by examining the expression of macrophage efferocytosis-related molecules, the effects of efferocytosis on IBD development, the various roles of macrophage efferocytosis in IBD, and treatment strategies for IBD that focus on efferocytosis.

Tissue factor-dependent colitogenic CD4+ T cell thrombogenicity is regulated by activated protein C signalling

Patients with inflammatory bowel disease (IBD) have an increased risk of venous thromboembolism (VTE), but the underlying mechanistic basis remains poorly defined. Here, we find that colitogenic CD4+ T cells express tissue factor (TF) and promote rapid TF-dependent plasma thrombin generation. TF+CD3+CD4+ T cells are present in both the colons of mice with experimental colitis and blood and colonic tissue from patients with IBD. Expression of genes involved in regulating coagulation, including Protein C (PC; encoded by PROC) and its receptor (PROCR), are dysregulated in IBD patient gut biopsy tissues. Moreover, activated PC signalling reduces the procoagulant activity mediated by TF+CD4+ T cells. Our data thus identify TF-induced, colitogenic T cell-mediated thrombogenicity, and also demonstrate a new function for activated PC signalling in regulating T cell thrombo-inflammatory activity.

Network pharmacology and experimental verification in vivo reveal the mechanism of Zhushao Granules against ulcerative colitis

BACKGROUND

Zhushao Granules (ZSG) had exhibited beneficial effects in the treatment of ulcerative colitis (UC) as an effective herbal prescription in Traditional Chinese Medicine. However, the underlying anti-inflammatory mechanism of ZSG remains unclear. This study aimed to decipher the mechanism of ZSG against UC combining network pharmacology and animal-based experiments.

METHODS

Network pharmacology was employed to identify active components and therapeutic targets of ZSG against UC. The protein-protein interaction (PPI) network was constructed among the therapeutic targets using the STRING database, and GO and pathway analyses were carried out using DAVID. Then, the "herb-component-target-pathway" network based on therapeutic targets was established and the topological parameters were subsequently calculated to identify hub active components, targets and pathways by Cytoscape. Finally, the therapeutic function and the special pathway of ZSG against UC were validated using a TNBS-induced UC model in BABL/c mice.

RESULTS

Ninety-four active components of ZSG and 460 potential targets were acquired from the Encyclopedia of Traditional Chinese Medicine and Tradition Chinese Medicine Systems Pharmacology Database and Analysis Platform. 884 potential targets of UC were obtained from OMIM and HINT. Sixty-two overlapping potential targets were identified as therapeutic targets of ZSG against UC. PPI network filtered out 61 therapeutic targets. GO and pathway analyses extracted 48, 25, and 98 terms corresponding to biological processes, molecular functions and Reactome pathways, respectively. Enrichment analysis suggested that the therapeutic targets were mainly involved in immune regulation, especially RIP-mediated NF-κB activation via ZBP1. Topological analysis of the "herb-component-target-pathway" network recognized 9 hub components, 20 hub targets and 18 hub pathways. The animal-based experiments revealed that ZSG ameliorated symptoms and histological changes in TNBS-induced colitis by significantly inhibiting the ZBP1/RIP/NF-κB pathway.

CONCLUSIONS

ZSG might alleviate the mucosal damage and ameliorate colitis via targeting ZBP1/RIP/NF-κB pathway, which laid the theoretical foundation for the clinical application and further study of ZSG and provided new insights into UC treatment.

Beyond the skin: endocrine, psychological and nutritional aspects in women with hidradenitis suppurativa

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic inflammatory skin disorder that primarily affects body folds and the genital area, with a higher prevalence in women across Europe. The pathogenesis of HS involves a complex interplay of intrinsic and extrinsic factors, including genetics, immunity, hormones, and environmental influences. HS is frequently associated with a variety of comorbidities, such as metabolic, endocrine, and gastrointestinal conditions, as well as mental health disorders. Although the symptoms of HS are generally similar in both men and women, female patients may experience exacerbations of HS due to hormonal fluctuations during menstruation, pregnancy, breastfeeding, and menopause. These hormonal changes require special consideration by clinicians when managing HS in women. Due to its chronic nature and frequent flare-ups, HS significantly impacts patients' quality of life, affecting social interactions, emotional well-being, and psychological health. Women with HS may also experience sexual dysfunction, which is further exacerbated by emotional burdens such as shame, loss of femininity, and diminished intimacy. This review highlights key aspects of HS, extending beyond its skin manifestations to address endocrine, psychological, and nutritional aspects in the female population. It also underscores the importance of multidisciplinary collaboration in providing comprehensive care for women with this debilitating condition. Given the limited and largely off-label treatment options, a holistic approach is essential to ensure an appropriate management.

Phillyrin ameliorates DSS-induced colitis in mice via modulating the gut microbiota and inhibiting the NF-κB/MLCK pathway

Phillyrin (PHY), also known as forsythin, is an active constituent isolated from the fruit of Forsythia suspensa (Thunb.) Vahl (Oleaceae). It exhibits anti-inflammatory, anti-viral, and antioxidant properties. However, the precise impact of PHY on colitis induced by dextran sodium sulfate (DSS) and its mechanism remain elusive. The present investigation revealed that PHY (12.5, 25.0, and 50.0 mg/kg) exhibited significant therapeutic efficacy in protecting mice against DSS-induced colitis. This effect was manifested as reduced weight loss, a shortened colon, increased secretion of inflammatory factors, increased intestinal permeability, and an enhanced disease activity index in mice with ulcerative colitis (UC). Molecular investigations have determined that PHY mitigates the nuclear translocation of nuclear factor kappa B, thereby downregulating myosin light-chain kinase-driven myosin light-chain phosphorylation. This mechanism results in the preservation of the integrity of the intestinal barrier. The outcomes of 16S rRNA sequencing suggest that PHY (50 mg/kg) augmented the relative abundance of certain probiotic strains, including Lactobacillaceae and Lachnospiraceae. Additionally, PHY supplementation elevated the short-chain fatty acid contents within the intestinal contents of mice with UC. In conclusion, pre-treatment with PHY may ameliorate the DSS-induced UC in mice by lowering the expression of inflammatory factors, protecting intestinal barrier function, and enhancing the structure of the intestinal flora.IMPORTANCEThe protective effect of phillyrin on DSS-induced colitis was explained for the first time, and the anti-inflammatory effect of phillyrin was demonstrated by fecal microbiota transplantation experiments mainly through intestinal flora.

Sanguinarine chloride hydrate mitigates colitis symptoms in mice through the regulation of the intestinal microbiome and metabolism of short-chain fatty acids

Sanguinarine constitutes the main components of Macleaya cordata, and exhibits diverse biological and pharmacological activities. This study investigated the effects of sanguinarine chloride hydrate (SGCH) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice. Five groups were designed to investigate the effects of SGCH on the pathological symptoms, the mRNA expression levels of inflammatory cytokines, colonic mucosal barrier damage, microbiota composition, and SCFAs metabolism in UC mice. The administration of SGCH in DSS-induced UC mice resulted in the amelioration of pathological symptoms, as evidenced by an increase in body weight, a decrease in disease activity index score, elongation of colon length, reduction in spleen index, and improvement in colon injury. SGCH can regulate the expression of inflammatory cytokines (IL-6, TNF-α, IL-1β and IL-10) and tight junction proteins (ZO-1 and Occludin) associated with UC. SGCH exhibited a significant decrease in NF-κB P65 mRNA expression levels, accompanied by a significantly reduced protein level of NF-κB P-P65/P65. Further studies revealed SGCH effectively reversed the decrease in intestinal microbiota diversity induced by UC, thereby promoting the growth of beneficial bacteria such as Akkermansia, Alistipes, and norank_o_Clostridia_UCG-014. Correlation analysis demonstrated a positive association between butanoic acid, propanoic acid, isobutyric acid, isovaleric acid, valeric acid, hexanoic acid with Colidextribacter, while Coriobacteriaceae_UCG-002 exhibited a negative correlation with butanoic acid, acetic acid and propanoic acid. In conclusion, the administration of SGCH can ameliorate clinical symptoms in UC mice, regulate the expression of inflammatory cytokines and tight junction proteins, modulate intestinal microbiota metabolism and SCFAs production.

Zinc and Inflammatory Bowel Disease: From Clinical Study to Animal Experiment

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract (GI) with a high incidence rate globally, and IBD patients are often accompanied by zinc deficiency. This review aims to summarize the potential therapeutic value of zinc supplementation in IBD clinical patients and animal models. Zinc supplementation can relieve the severity of IBD especially in patients with zinc deficiency. The clinical severity of IBD were mainly evaluated through some scoring methods involving clinical performance, endoscopic observation, blood biochemistry, and pathologic biopsy. Through conducting animal experiments, it has been found that zinc plays an important role in alleviating clinical symptoms and improving pathological lesions. In both clinical observation and animal experiment of IBD, the therapeutic mechanisms of zinc interventions have been found to be related to immunomodulation, intestinal epithelial repair, and gut microbiota's balance. Furthermore, the antioxidant activity of zinc was clarified in animal experiment. Appropriate zinc supplementation is beneficial for IBD therapy, and the present evidence highlights that alleviating zinc-deficient status can effectively improve the severity of clinical symptoms in IBD patients and animal models.

Unfolded protein response: An essential element of intestinal homeostasis and a potential therapeutic target for inflammatory bowel disease

Different physiological and pathological situations can produce alterations in the cell's endoplasmic reticulum (ER), leading to a condition known as ER stress, which can trigger an intricate intracellular signal transduction system known as the unfolded protein response (UPR). UPR is primarily tailored to restore proteostasis and ER equilibrium; otherwise, if ER stress persists, it can cause programmed cell death as a cytoprotective mechanism and drive inflammatory processes. Therefore, since intestinal cells strongly rely on UPR for their biological functions and unbalanced UPR has been linked to inflammatory, metabolic, and immune disorders, here we discussed the role of the UPR within the intestinal tract, focusing on the UPR contribution to inflammatory bowel disease development. Importantly, we also highlighted the promising potential of UPR components as therapeutic targets for intestinal inflammatory diseases.

IgG4 in the gut: Gastrointestinal IgG4-related disease or a new subtype of inflammatory bowel disease

IgG4-related disease (IgG4-RD) is a chronic inflammatory condition characterized by tissue infiltration with IgG4-positive plasma cells, leading to fibrosis and organ dysfunction. While primarily affecting the pancreas, bile ducts, and salivary glands, IgG4-RD can also involve the gastrointestinal tract, raising questions about its relationship with inflammatory bowel disease (IBD). Recent studies suggest that patients with IBD may exhibit histological and serological features consistent with IgG4-RD, such as a dense lymphoplasmacytic infiltration, a storiform-type of fibrosis and a prominent IgG4 immune response. This overlap represents a diagnostic challenge, as differentiating between primary IBD and IgG4-RD involving the gut is crucial for appropriate treatment. Further research is essential to delineate the prevalence of tissue and serum IgG4 expression in patients with IBD. This approach could classify subtypes of IBD, enabling advancements in non-invasive diagnosis and monitoring as well as personalized therapies. The purpose of this review is to summarize the available evidence regarding intestinal involvement in IgG4-RD and the role of both serum and tissue IgG4 in inflammatory bowel diseases IBD.

The role of BATF in immune cell differentiation and autoimmune diseases

As a member of the Activator Protein-1 (AP-1) transcription factor family, the Basic Leucine Zipper Transcription Factor (BATF) mediates multiple biological functions of immune cells through its involvement in protein interactions and binding to DNA. Recent studies have demonstrated that BATF not only plays pivotal roles in innate and adaptive immune responses but also acts as a crucial factor in the differentiation and function of various immune cells. Lines of evidence indicate that BATF is associated with the onset and progression of allergic diseases, graft-versus-host disease, tumors, and autoimmune diseases. This review summarizes the roles of BATF in the development and function of innate and adaptive immune cells, as well as its immunoregulatory effects in the development of autoimmune diseases, which may enhance the current understanding of the pathogenesis of autoimmune diseases and facilitate the development of new therapeutic strategies.

Joint analysis of genome-wide cross-trait and multi-omics reveals molecular mechanisms of inflammatory bowel disease and nominates its novel therapeutic genes

Inflammatory bowel disease (IBD) with the two predominant endophenotypes-Crohn's disease (CD) and ulcerative colitis (UC)-represents a group of chronic gastrointestinal inflammatory conditions. Since most genetic associations with IBD are often limited to independent subtypes, we reported a genome-wide association study (GWAS) cross-trait analysis combined with CD and UC to enhance statistical power. Initially, we detected 256 association signals at 54 genomic susceptibility loci and further characterized the functionality of variants within these regions. Subsequently, we revealed tissue and cell-specific heritability enrichment, particularly in whole blood, small intestine terminal ileum, spleen, lung, and colon transverse. Leveraging multi-omics datasets, we adopted a two-pronged approach comprising summary data-based Mendelian randomization (SMR) and transcriptome-wide association study (TWAS) to pinpoint likely causal genes and variants. Further, RNA-seq analysis facilitated the evaluation of differential expression and co-expression in intestinal tissues. Through a multi-stage prioritization strategy, compelling evidence for putative targets was nominated; notably highlighting several potential susceptibility genes such as IL27 and SBNO2. Finally, we utilized Mendelian randomization (MR) analysis with diverse datasets to verify the convergence of these two endophenotype-driven genes. Our investigation yields valuable insights to inform genetic mechanisms in IBD and reveal potential causal gene targets.

Novel targets for mucosal healing in inflammatory bowel disease therapy

Inflammatory bowel disease (IBD) is a chronic condition affecting the gastrointestinal tract, primarily manifesting as ulcerative colitis (UC) or Crohn's disease (CD). Both inflammation and disruption of the intestinal epithelial barrier are key factors in IBD pathogenesis. Substantial evidence has revealed a significant association between aberrant immune responses and impairment of the intestinal epithelial barrier in IBD pathogenesis. The components of the intestinal epithelium, particularly goblet cells and Paneth cells, are crucial to gut homeostasis, as they secrete mucin, antimicrobial peptides (AMPs), and cytokines. Furthermore, impairment of epithelial integrity, which is regulated by tight junctions, is a hallmark of IBD pathology. While common treatments for IBD, such as anti-inflammatory drugs, target various signaling pathways with varying efficacies, therapeutic approaches focused on mucosal and epithelial barrier healing have been largely neglected. Moreover, high costs, side effects, and insufficient or inconsistent therapeutic outcomes remain major drawbacks of conventional anti-IBD drugs. Recent studies on epithelial barrier regeneration and permeability reduction have introduced promising therapeutic targets, including farnesoid X receptor (FXR), urokinase-type plasminogen activator (uPA)-urokinase-type plasminogen activator receptor (uPAR) interaction, fecal microbiota transplantation (FMT), and insulin receptor (INSR). Notably, the simultaneous targeting of intestinal inflammation and promotion of epithelial barrier healing shows promise for efficient IBD treatment. Future research should explore targeted therapies and combination treatments, including natural remedies, microbiota colonization, stem cell approaches, and computer-aided drug design. It is also crucial to focus on accurate prognosis and developing a thorough understanding of IBD development mechanisms.

Association between allergic diseases and mucosal healing in ulcerative colitis

Allergic diseases and ulcerative colitis (UC) share pathophysiological similarities. This study aimed to investigate the unclear association between allergic diseases and mucosal healing (MH), an important factor in the prognosis of UC. We studied 289 Japanese patients with UC. Information on allergic diseases (bronchial asthma, atopic dermatitis, pollen allergy, food allergy, and drug allergy), as diagnosed by physicians, was collected through self-reported questionnaires. The definition of MH was Mayo Endoscopic Score 0. The association between each allergic disease and its multimorbidity with MH was evaluated using multivariate logistic regression analyses. Pollen allergy was the most common allergic condition (36.3%). Pollen allergy and food allergy were independently associated with MH (pollen allergy adjusted OR: 1.82 [95% CI: 1.01-3.26]; food allergy adjusted OR: 3.47 [95% CI: 1.26-9.68]). The rates of MH for 0 and 3 or more allergic diseases were 24.6% and 4.2%, respectively. After adjustment for confounders, 3 or more allergic diseases were independently associated with MH (adjusted OR: 8.13 [95% CI: 2.17-34.04], p for trend = 0.020). This study demonstrates a significant positive association between specific allergic diseases (pollen and food allergies) and MH in UC patients, with a stronger association in cases of allergic multimorbidity.

Decursinol angelate relieves inflammatory bowel disease by inhibiting the ROS/TXNIP/NLRP3 pathway and pyroptosis

Introduction

Despite evidence of the efficacy of decursinol angelate (DA), a prescription medication derived farom traditional Chinese medicine, in alleviating inflammatory bowel disease (IBD), the precise mechanisms behind its action remain unclear.

Methods

Lipopolysaccharides (LPS) and dextran sodium sulfate (DSS) induction were used as in vitro and in vivo models of IBD, respectively, to assess the role of DA in alleviating IBD. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the expression levels of pro-inflammatory cytokines in mouse serum, Western blot was performed to detect the expression of TXNIP/NLRP3 pathway tight junction (TJ) proteins in colon tissues and cells, and immunohistochemistry, immunofluorescence and immunohistochemistry, immunofluorescence and qRT-PCR were used to validate the proteins related to this signaling pathway. Molecular docking technique and co-immunoprecipitation (Co-IP) method assay were applied to evaluate the targeting effect of DA on NLRP3 proteins, and MCC950, a specific inhibitor of NLRP3, was used as a positive control for validation.

Results

Our research indicates that DA's distinctive molecular mechanism could entail binding to the NLRP3 protein, thereby suppressing the activation of the NLRP3 pathway and diminishing the assembly and activation of the NLRP3 inflammasome, thus functioning as an anti-inflammatory agent.

Conclusion

DA may play a role in improving BD by inhibiting the activation of the ROS/TXNIP/NLRP3 signaling pathway and the release of inflammatory mediators, and by repairing the intestinal barrier function.

Cardiovascular disease: extraintestinal manifestation of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a spectrum of diseases characterized by the interplay of the aberrant immune system, genetic factors, environmental factors, and intestinal microbiota, resulting in relapsing inflammation of the gastrointestinal tract. Underlying pro-inflammatory state and immune dysregulation act as a catalyst for increasing the likelihood of developing extraintestinal manifestations, including cardiovascular diseases (CVD) like atherosclerosis, pericarditis, myocarditis, venous and arterial thromboembolism, arrhythmias, despite a lower prevalence of classic CVD risk factors, like high body mass index or dyslipidemia compared to the general population. Chronic inflammation damages endothelium resulting in the recruitment of inflammatory cells, which induce cytotoxicity, lipoprotein oxidation, and matrix degradation, which increases the risk of atherosclerosis. Additionally, intestinal dysbiosis disrupts the intestinal mucosal barrier, releasing endotoxins and lipopolysaccharides into circulation, further exaggerating the atherosclerotic process. Abnormal collagen metabolism and alteration of nitric oxide-mediated vasodilation lead to blood pressure dysregulation in patients with IBD. Therefore, it is essential to make lifestyle modifications like smoking cessation, dietary changes, and increasing physical activity with adherence to medication to mitigate the risk of developing CVD in patients with IBD. This article reviews the potential links between IBD and the increased risk of CVD in such individuals.

Gut‑liver axis in liver disease: From basic science to clinical treatment (Review)

Incidence of a number of liver diseases has increased. Gut microbiota serves a role in the pathogenesis of hepatitis, cirrhosis and liver cancer. Gut microbiota is considered 'a new virtual metabolic organ'. The interaction between the gut microbiota and liver is termed the gut‑liver axis. The gut‑liver axis provides a novel research direction for mechanism of liver disease development. The present review discusses the role of the gut‑liver axis and how this can be targeted by novel treatments for common liver diseases.

Ulcerative Colitis, LAIR1 and TOX2 Expression, and Colorectal Cancer Deep Learning Image Classification Using Convolutional Neural Networks

BACKGROUND

Ulcerative colitis is a chronic inflammatory bowel disease of the colon mucosa associated with a higher risk of colorectal cancer.

OBJECTIVE

This study classified hematoxylin and eosin (H&E) histological images of ulcerative colitis, normal colon, and colorectal cancer using artificial intelligence (deep learning).

METHODS

A convolutional neural network (CNN) was designed and trained to classify the three types of diagnosis, including 35 cases of ulcerative colitis (n = 9281 patches), 21 colon control (n = 12,246), and 18 colorectal cancer (n = 63,725). The data were partitioned into training (70%) and validation sets (10%) for training the network, and a test set (20%) to test the performance on the new data. The CNNs included transfer learning from ResNet-18, and a comparison with other CNN models was performed. Explainable artificial intelligence for computer vision was used with the Grad-CAM technique, and additional LAIR1 and TOX2 immunohistochemistry was performed in ulcerative colitis to analyze the immune microenvironment.

RESULTS

Conventional clinicopathological analysis showed that steroid-requiring ulcerative colitis was characterized by higher endoscopic Baron and histologic Geboes scores and LAIR1 expression in the lamina propria, but lower TOX2 expression in isolated lymphoid follicles (all p values < 0.05) compared to mesalazine-responsive ulcerative colitis. The CNN classification accuracy was 99.1% for ulcerative colitis, 99.8% for colorectal cancer, and 99.1% for colon control. The Grad-CAM heatmap confirmed which regions of the images were the most important. The CNNs also differentiated between steroid-requiring and mesalazine-responsive ulcerative colitis based on H&E, LAIR1, and TOX2 staining. Additional classification of 10 new cases of colorectal cancer (adenocarcinoma) were correctly classified.

CONCLUSIONS

CNNs are especially suited for image classification in conditions such as ulcerative colitis and colorectal cancer; LAIR1 and TOX2 are relevant immuno-oncology markers in ulcerative colitis.

Protective Potential of Limosilactobacillus fermentum Strains and Their Mixture on Inflammatory Bowel Disease via Regulating Gut Microbiota in Mice

The aim of this study is to investigate the protective potential of Limosilactobacillus fermentum IM57, IR51, and IR62 strains, isolated from infant feces, and their mixture against inflammatory bowel disease (IBD). The strains exhibited robust antioxidant activities and anti-inflammatory properties in RAW 264.7 cells. Subsequently, the potential protective effects of each of these three strains, along with their mixture, were evaluated in a murine colitis model induced by dextran sodium sulfate (DSS). Noteworthy improvements in physiological parameters such as body weight, disease activity index, and colon length were observed in mice treated with the mixture followed by IR62. Additionally, administration of each strain and the mixture mitigated DSS-induced changes in gut microbiota composition with increased abundance of Lactobacillus, Bifidobacterium, Ruminococcus, and Muribaculum, compared to DSS-treated mice. Interestingly, the abundance of Muribaculum increased approximately 2.4-fold after administration of the mixture compared to before administration. Additionally, the concentration of short-chain fatty acids (SCFAs) was significantly reduced in DSS-treated group compared to the control group, while the mixture treatment group had the highest concentration of SCFAs. Furthermore, due to these changes in microbiota and the leading metabolites induced by treatment of the mixture, DSS-induced dysregulation of inflammationand barrier function-related mRNA expressions was significantly inhibited in the group fed with the mixture. Consequently, this study indicates that the multi-strain mixture of L. fermentum strains may play a crucial role in modulating gut microbiota, thereby alleviating IBD through the synergistic effect of the individual effects of the three strains.

Design, synthesis, in vitro and in vivo biological evaluation of pterostilbene derivatives for anti-inflammation therapy

Pterostilbene (PST) is a naturally derived stilbene compound in grapes, blueberries, and other fruits. It is also a natural dietary compound with a wide range of biological activities such as antioxidant, anti-inflammatory, antitumor, and so on. Structural modifications based on the chemical scaffold of the pterostilbene skeleton are of great importance for drug discovery. In this study, pterostilbene skeletons were used to design novel anti-inflammatory compounds with high activity and low toxicity. A total of 30 new were found and synthesised, and their anti-inflammatory activity and safety were screened. Among them, compound E2 was the most active (against NO: IC50 = 0.7 μM) than celecoxib. Further studies showed that compound E2 exerted anti-inflammatory activity by blocking LPS-induced NF-κB/MAPK signalling pathway activation. In vivo experiments revealed that compound E2 had a good alleviating effect on acute colitis in mice. In conclusion, compound E2 may be a promising anti-inflammatory lead compound.

SARS-CoV-2 vaccination in inflammatory bowel disease patients is not associated with flares: a retrospective single-centre Swiss study

INTRODUCTION

Vaccination hesitancy is an important barrier to vaccination among IBD patients. The development of adverse events is the main concern reported. The purpose of this monocentric study was to assess SARS-CoV-2 vaccination safety in IBD patients by evaluating the postvaccination flare risk and incidence of overall adverse events.

METHODS

Surveys were handed out on three consecutive months to each patient presenting at the Crohn-Colitis Centre, where they documented their vaccination status and any side effects experienced after vaccination.Dates of flares occurring in 2021 were recorded from their electronic medical records. Baseline and IBD characteristics and flare incidence were compared between the vaccinated and unvaccinated patients, and among the vaccinated population before and after their vaccination doses. The characteristics of patients who developed side effects and of those who did not were compared.

RESULTS

We enrolled 396 IBD patients, of whom 91% were vaccinated. The proportion of patients who experienced flares was statistically not different between the vaccinated and the unvaccinated population (1.8 vs 2.6 flares per 100 person-months (p = 0.28)). Among vaccinated patients, there was no difference across the prevaccination, 1 month post any vaccination, and more than 1 month after any vaccination periods, and between the Spikevax and Cominarty subgroups. Overall, 46% of patients reported vaccination side effects, mostly mild flu-like symptoms.

CONCLUSION

SARS-CoV-2 vaccination with mRNA vaccines seems safe, with mostly mild side effects. The IBD flare risk is not increased in the month following any vaccination.

In reviewing the emerging biomarkers of human inflammatory bowel disease (IBD): Endothelial progenitor cells (EPC) and their vesicles as potential biomarkers of cardiovascular manifestations and targets for personalized treatments

Inflammatory bowel diseases (IBD) are chronic inflammatory and pathological conditions of the gastrointestinal tract, which include two main clinical subtypes: Crohn's disease (CD) and ulcerative colitis (UC). IBDs show an increase in their age-standardized global incidence rate worldwide, with no gender differences, although the age-standardized mortality rate has decreased over the years. Indeed, thanks to recent therapies with novel mechanisms of action, including those with biologics and small molecules, it has been possible to reduce the mortality rate of IBDs. However, a significant percentage of IBD patients remain refractory to these multiple advanced therapies. Therefore, another challenge of IBD research remains the development of novel therapies with novel agents or cells that could improve the quality of life and outcome of IBD patients. Furthermore, another aspect to be studied in IBDs is not only the high risk of progression not only to neoplastic transformation but also to the development of cardiovascular disease (CVD). Consequently, 25-40 % of IBD patients present with cardiovascular manifestations. Here, we propose that the altered number and functions of endothelial progenitor cells (EPCs) may represent one of the crucial mechanisms associated with incomplete/delayed healing of IBD and may offer the possibility of using them, as well as their vesicles and content, as novel biomarkers and potential candidates of cell therapy for IBD. The advantages and limitations are extensively described and discussed.

Zhumeria majdae essential oil attenuates TNBS-induced colitis in rats by regulating inflammatory and apoptotic pathways

BACKGROUND AND AIM

Zhumeria majdae, a unique native plant of southern Iran, has been traditionally used to treat various health issues. Preclinical studies suggest its therapeutic potential for immunological and inflammatory disorders. This study investigates the effect of Z. majdae essential oil (ZMEO) on TNBS-induced colitis in rats, focusing on the NF-κB/p38 MAPK/Nrf-2 pathway.

EXPERIMENTAL PROCEDURE

Forty-eight male Wistar rats were used, with all groups except the sham group receiving a single intra-rectal dose of TNBS. Three different doses of ZMEO and also 1 mg/kg dexamethasone were administered orally for 2 weeks. Colon tissue was analyzed for ulcer index, histological changes, inflammatory cytokines, apoptotic factors, and levels of NF-κB, p38 MAPK, and Nrf-2.

KEY RESULTS

GC-mass analysis identified 25 compounds with linalool (52.01%) and camphor (31.01%) as the major compounds in ZMEO. ZMEO ameliorated colon injuries, reduced ulcer index, and prevented the elevation of pro-inflammatory cytokines and pro-apoptotic proteins. It also increased the levels of IL-10 and Bcl-2 proteins. Furthermore, ZMEO decreased the expression of p-NF-κB and p38 MAPK while increasing the expression of pNrf-2.

CONCLUSIONS

ZMEO mitigates colon damage associated with IBD by suppressing inflammatory cytokines and pro-apoptotic proteins possibly through modulating the NF-κB/p38 MAPK/Nrf-2 signaling pathway.

Dysregulation of T cell response in the pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD), comprised of Crohn's disease (CD) and ulcerative colitis (UC), are gut inflammatory diseases that were earlier prevalent in the Western Hemisphere but now are on the rise in the East, with India standing second highest in the incidence rate in the world. Inflammation in IBD is a cause of dysregulated immune response, wherein helper T (Th) cell subsets and their cytokines play a major role in the pathogenesis of IBD. In addition, gut microbiota, environmental factors such as dietary factors and host genetics influence the outcome and severity of IBD. Dysregulation between effector and regulatory T cells drives gut inflammation, as effector T cells like Th1, Th17 and Th9 subsets Th cell lineages were found to be increased in IBD patients. In this review, we attempted to discuss the role of different Th cell subsets together with other T cells like CD8+ T cells, NKT and γδT cells in the outcome of gut inflammation in IBD. We also highlighted the potential therapeutic candidates for IBD.

Evaluation of the Effect of Probiotic Supplementation on Intestinal Barrier Integrity and Epithelial Damage in Colitis Disease: A Systematic Review

CONTEXT

Previous reviews have focused on the effects of probiotics on colitis, but there is a need to understand their impact on barrier integrity and tight junction protein improvement in colitis.

OBJECTIVE

This study aimed to systematically examine the effects of probiotic use on barrier integrity in colitis disease. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

DATA SOURCES

A systematic search in PubMed, Web of Science, Scopus, and Cochrane databases identified 2537 articles.

DATA EXTRACTION

As a result of the search, 2537 articles were accessed. Study results were summarized descriptively through discussions by intervention conditions, study population, measurement methods, and key findings. The included studies were independently reviewed and all authors reached consensus on the quality and major findings from the included articles. Forty-six studies that met the inclusion criteria were analyzed within the scope of the systematic review.

RESULTS

Although the study primarily utilized probiotics from the Lactobacillaceae family (notably, L casei, L reuteri, L rhamnosus, L plantarum, and L pentosus) and the Bifidobacteriaceae family (notably, B breve, B animalis, and B dentium), other probiotics also demonstrated positive effects on tight junction proteins. These effects are attributed to the production of bioactive and metabolic compounds, as well as short-chain fatty acids, which combat pathogens and reduce anti-inflammatory agents. However, it was observed that the effects of these probiotics on tight junction proteins varied depending on the strain and dose.

CONCLUSION

The beneficial effects of probiotics on remission in inflammatory bowel disease are well documented. Studies show that probiotics generally improve intestinal barrier function, but factors such as dose, duration, and bacterial species combinations need further clarification. Additionally, comprehensive studies are needed to understand how improved barrier function affects absorption in individuals.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023452774.

Microsomal Prostaglandin E Synthase-1 Controls Colonic Prostaglandin E2 Production and Exerts a Protective Effect on Colitis Induced by Trinitrobenzene Sulfonic Acid in Mice

Microsomal prostaglandin E synthase-1 (mPGES-1) is an isozyme of the prostaglandin (PG) E synthase that acts downstream of cyclooxygenase and catalyzes the conversion of PGH2 to PGE2. The impact of genetic deletion of mPGES-1 on the development of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis, a well-established model of inflammatory bowel disease (IBD), was investigated in this study. After administration of TNBS, mice deficient in mPGES-1 (mPGES-1-/- mice) showed more severe colitis than did wild-type (WT) mice. Histological examination revealed that mPGES-1-/- mice had markedly exacerbated symptoms of colitis. mPGES-1 expression was detectable in the colons of WT mice at both the mRNA and protein levels. Lack of mPGES-1 resulted in marked reduction of colonic PGE2 production. Our study also showed a significant increase in colonic expression of interleukin-17A (IL-17A), as well as interferon γ (IFNγ) and tumor necrosis factor α, during colitis in mPGES-1-/- mice compared with that in WT mice. Furthermore, loss of mPGES-1 increased the populations of IL-17A-producing T-helper (Th) 17 and IFNγ-producing Th1 cells in mesenteric lymph nodes. These results suggest that mPGES-1 is the main enzyme responsible for colonic PGE2 production and deficiency of mPGES-1 facilitates the development of colitis and T-cell-mediated immunity. mPGES-1 might, therefore, impact T-cell-related immune response associated with IBD.

Potential diagnostic markers and therapeutic targets for non-alcoholic fatty liver disease and ulcerative colitis based on bioinformatics analysis and machine learning

Background

Non-alcoholic fatty liver disease (NAFLD) and ulcerative colitis (UC) are two common health issues that have gained significant global attention. Previous studies have suggested a possible connection between NAFLD and UC, but the underlying pathophysiology remains unclear. This study investigates common genes, underlying pathogenesis mechanisms, identification of diagnostic markers applicable to both conditions, and exploration of potential therapeutic targets shared by NAFLD and UC.

Methods

We obtained datasets for NAFLD and UC from the GEO database. The DEGs in the GSE89632 dataset of the NAFLD and GSE87466 of the UC dataset were analyzed. WGCNA, a powerful tool for identifying modules of highly correlated genes, was employed for both datasets. The DEGs of NAFLD and UC and the modular genes were then intersected to obtain shared genes. Functional enrichment analysis was conducted on these shared genes. Next, we utilize the STRING database to establish a PPI network. To enhance visualization, we employ Cytoscape software. Subsequently, the Cytohubba algorithm within Cytoscape was used to identify central genes. Diagnostic biomarkers were initially screened using LASSO regression and SVM methods. The diagnostic value of ROC curve analysis was assessed to detect diagnostic genes in both training and validation sets for NAFLD and UC. A nomogram was also developed to evaluate diagnostic efficacy. Additionally, we used the CIBERSORT algorithm to explore immune infiltration patterns in both NAFLD and UC samples. Finally, we investigated the correlation between hub gene expression, diagnostic gene expression, and immune infiltration levels.

Results

We identified 34 shared genes that were found to be associated with both NAFLD and UC. These genes were subjected to enrichment analysis, which revealed significant enrichment in several pathways, including the IL-17 signaling pathway, Rheumatoid arthritis, and Chagas disease. One optimal candidate gene was selected through LASSO regression and SVM: CCL2. The ROC curve confirmed the presence of CCL2 in both the NAFLD and UC training sets and other validation sets. This finding was further validated using a nomogram in the validation set. Additionally, the expression levels of CCL2 for NAFLD and UC showed a significant correlation with immune cell infiltration.

Conclusion

This study identified a gene (CCL2) as a biomarker for NAFLD and UC, which may actively participate in the progression of NAFLD and UC. This discovery holds significant implications for understanding the progression of these diseases and potentially developing more effective diagnostic and treatment strategies.

Therapeutic potential of mesenchymal stem cell-derived extracellular vesicles: A focus on inflammatory bowel disease

BACKGROUND

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as key regulators of intercellular communication, orchestrating essential biological processes by delivering bioactive cargoes to target cells. Available evidence suggests that MSC-EVs can mimic the functions of their parental cells, exhibiting immunomodulatory, pro-regenerative, anti-apoptotic, and antifibrotic properties. Consequently, MSC-EVs represent a cell-free therapeutic option for patients with inflammatory bowel disease (IBD), overcoming the limitations associated with cell replacement therapy, including their non-immunogenic nature, lower risk of tumourigenicity, cargo specificity and ease of manipulation and storage.

MAIN TOPICS COVERED

This review aims to provide a comprehensive examination of the therapeutic efficacy of MSC-EVs in IBD, with a focus on their mechanisms of action and potential impact on treatment outcomes. We examine the advantages of MSC-EVs over traditional therapies, discuss methods for their isolation and characterisation, and present mechanistic insights into their therapeutic effects through transcriptomic, proteomic and lipidomic analyses of MSC-EV cargoes. We also discuss available preclinical studies demonstrating that MSC-EVs reduce inflammation, promote tissue repair and restore intestinal homeostasis in IBD models, and compare these findings with those of clinical trials.

CONCLUSIONS

Finally, we highlight the potential of MSC-EVs as a novel therapy for IBD and identify challenges and opportunities associated with their translation into clinical practice.

HIGHLIGHTS

The source of mesenchymal stem cells (MSCs) strongly influences the composition and function of MSC-derived extracellular vesicles (EVs), affecting their therapeutic potential. Adipose-derived MSC-EVs, known for their immunoregulatory properties and ease of isolation, show promise as a treatment for inflammatory bowel disease (IBD). MicroRNAs are consistently present in MSC-EVs across cell types and are involved in pathways that are dysregulated in IBD, making them potential therapeutic agents. For example, miR-let-7a is associated with inhibition of apoptosis, miR-100 supports cell survival, miR-125b helps suppress pro-inflammatory cytokines and miR-20 promotes anti-inflammatory M2 macrophage polarisation. Preclinical studies in IBD models have shown that MSC-EVs reduce intestinal inflammation by suppressing pro-inflammatory mediators (e.g., TNF-α, IL-1β, IL-6) and increasing anti-inflammatory factors (e.g., IL-4, IL-10). They also promote mucosal healing and strengthen the integrity of the gut barrier, suggesting their potential to address IBD pathology.