Ulcerative colitis: understanding its cellular pathology could provide insights into novel therapies

Natural approaches for the management of ulcerative colitis: evidence of preclinical and clinical investigations

Ulcerative colitis (UC) is a recurring autoimmune disorder characterized by persistent inflammation in the mucosal lining of the lower part of the large intestine. Conventional treatment options such as salicylates, corticosteroids, and immunosuppressants often come with severe side effects, limited bioavailability, and the development of drug resistance, which hampers their therapeutic effectiveness. Therefore, it is imperative to explore natural strategies as safe and alternative treatments for UC. Currently, around 40% of UC patients find relief through natural constituents, which can help reduce toxic side effects and maintain clinical remission. This review aims to provide a summary of both preclinical and clinical evidence supporting the efficacy of various natural substances in the prophylaxis of UC. These natural options include plant extracts, essential oils, nutraceuticals, and phytochemicals. Furthermore, we will delve into the potential mechanisms that underlie the protective and curative actions of these novel herbal agents. In summary, this review will explore the effectiveness of natural remedies for UC, shedding light on their preclinical and clinical findings and the mechanisms behind their therapeutic actions. These alternatives offer hope for improved treatment outcomes and reduced side effects for individuals suffering from this challenging autoimmune condition.

Cyclic adenosine 3', 5'-monophosphate (cAMP) signaling is a crucial therapeutic target for ulcerative colitis

The pathogenesis of ulcerative colitis (UC), a chronic intestine inflammatory disease primarily affecting adolescents, remains uncertain. Contemporary studies suggest that a confluence of elements, including genetic predispositions, environmental catalysts, dysregulated immune responses, and disturbances in the gut microbiome, are instrumental in the initiation and advancement of UC. Among them, inflammatory activation and mucosal barrier damage caused by abnormal immune regulation are essential links in the development of UC. The impairment of the mucosal barrier is intricately linked to the interplay of various cellular mechanisms, including oxidative stress, autophagy, and programmed cell death. An extensive corpus of research has elucidated that level of cyclic adenosine 3',5'-monophosphate (cAMP) undergo modifications in the midst of inflammation and participate in a diverse array of cellular operations that mitigate inflammation and the impairment of the mucosal barrier. Consequently, a plethora of pharmacological agents are currently under development, with some advancing through clinical trials, and are anticipated to garner approval as novel therapeutics. In summary, cAMP exerts a crucial influence on the onset and progression of UC, with fluctuations in its activity being intimately associated with the severity of the disease's manifestation. Significantly, this review unveils the paramount role of cAMP in the advancement of UC, offering a tactical approach for the clinical management of individuals afflicted with UC.

Structural characteristics of a polysaccharide from Armillariella tabescens and its protective effect on colitis mice via regulating gut microbiota and intestinal barrier function

A new polysaccharide fraction (ATP) was obtained from Armillariella tabescens mycelium. Structural analysis suggested that the backbone of ATP was →4)-α-D-Glcp(1 → 2)-α-D-Galp(1 → 2)-α-D-Glcp(1 → 4)-α-D-Glcp(1→, which branched at O-3 of →2)-α-D-Glcp(1 → and terminated with T-α-D-Glcp or T-α-D-Manp. Besides, ATP significantly alleviated ulcerative colitis (UC) symptoms and inhibited the production of pro-inflammation cytokines (IL-1β, IL-6). Meanwhile, ATP could improve colon tissue damage by elevating the expression of MUC2 and tight junction proteins (ZO-1, occludin and claudin-1) levels and enhance intestinal barrier function through inhibiting the activation of MMP12/MLCK/p-MLC2 signaling pathway. Further studies exhibited that ATP could increase the relative abundance of beneficial bacteria such as f. Muribaculacese, g. Muribaculaceae, and g. Alistips, and decrease the relative abundance of g. Desulfovibrio, g. Colidextribacter, g. Ruminococcaceae and g.Oscillibacter, and regulate the level of short-chain fatty acids. Importantly, FMT intervention with ATP-derived microbiome certified that gut microbiota was involved in the protective effects of ATP on UC. The results indicated that ATP was potential to be further developed into promising therapeutic agent for UC.

Exploration and verification a 13-gene diagnostic framework for ulcerative colitis across multiple platforms via machine learning algorithms

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with intricate pathogenesis and varied presentation. Accurate diagnostic tools are imperative to detect and manage UC. This study sought to construct a robust diagnostic model using gene expression profiles and to identify key genes that differentiate UC patients from healthy controls. Gene expression profiles from eight cohorts, encompassing a total of 335 UC patients and 129 healthy controls, were analyzed. A total of 7530 gene sets were computed using the GSEA method. Subsequent batch correction, PCA plots, and intersection analysis identified crucial pathways and genes. Machine learning, incorporating 101 algorithm combinations, was employed to develop diagnostic models. Verification was done using four external cohorts, adding depth to the sample repertoire. Evaluation of immune cell infiltration was undertaken through single-sample GSEA. All statistical analyses were conducted using R (Version: 4.2.2), with significance set at a P value below 0.05. Employing the GSEA method, 7530 gene sets were computed. From this, 19 intersecting pathways were discerned to be consistently upregulated across all cohorts, which pertained to cell adhesion, development, metabolism, immune response, and protein regulation. This corresponded to 83 unique genes. Machine learning insights culminated in the LASSO regression model, which outperformed others with an average AUC of 0.942. This model's efficacy was further ratified across four external cohorts, with AUC values ranging from 0.694 to 0.873 and significant Kappa statistics indicating its predictive accuracy. The LASSO logistic regression model highlighted 13 genes, with LCN2, ASS1, and IRAK3 emerging as pivotal. Notably, LCN2 showcased significantly heightened expression in active UC patients compared to both non-active patients and healthy controls (P < 0.05). Investigations into the correlation between these genes and immune cell infiltration in UC highlighted activated dendritic cells, with statistically significant positive correlations noted for LCN2 and IRAK3 across multiple datasets. Through comprehensive gene expression analysis and machine learning, a potent LASSO-based diagnostic model for UC was developed. Genes such as LCN2, ASS1, and IRAK3 hold potential as both diagnostic markers and therapeutic targets, offering a promising direction for future UC research and clinical application.

Expression profile of serum LncRNAs MALAT-1 and CCAT-1 and their correlation with Mayo severity score in ulcerative colitis patients can diagnose and predict the prognosis of the disease

Background

Ulcerative colitis (UC) has emerged as an accelerated-incidence chronic condition. UC has been identified as a precancerous lesion for colorectal cancer. Up-to-date genomic research revealed the value of many noncoding RNAs (ncRNAs) in UC pathogenesis, diagnosis, and prognosis.

Aim

The present study was aimed at measuring both MALAT-1 and CCAT-1 in the sera of UC patients as diagnostic and prognostic biomarkers and correlating them with the Mayo score which is a novel predictive indicator of malignant transformation as well as with clinicopathological characteristics of the disease.

Patients and methods

Sixty-six UC patients and 80 healthy individuals participated in this study, the serum fold changes of MALAT-1 and CCAT-1 were measured by using quantitative real-time PCR (qRT-PCR).

Results

The current study findings include overexpressed lncRNAs MALAT-1 and CCAT-1 in the sera of ulcerative colitis patients [(median (IQR) = 2.290 (0.16-9.36), mean ± SD = 3.37 ± 3.904 for MALAT-1, and median (IQR) = 7.305 (0.57-16.96), mean ± SD = 6.81 ± 4.002 for CCAT-1 than controls, ROC curve analysis reported that these genes could predict UC. Both genes were positively correlated with each other which enforces their synergistic effects. Both genes are diagnostic for UC patients.We related studied genes to the severity of the disease. In addition to a significant positive correlation between each gene with ESR and Mayo score, we further classified the patients according to severity (according to Mayo score to remission, mild, moderate, and severe groups) with the following results; lower levels of MALAT-1 and CCAT-1 were significantly associated with mild disease and increased gradually with more severe forms of the disease (p < 0.05). Linear regression analysis with Mayo Score as a dependent variable revealed that only the predictive power of CCAT-1 and ESR are significant. Moreover, ROC curve analysis when compared to that of the Mayo score revealed that CCAT-1 reached 99 % accuracy. In summary, both genes are prognostic factors for UC patients.

Conclusion

MALAT-1 and CCAT-1 are diagnostic and prognostic serum biomarkers of ulcerative colitis.

Effects of Mediterranean Diet, Curcumin, and Resveratrol on Mild-to-Moderate Active Ulcerative Colitis: A Multicenter Randomized Clinical Trial

This study aimed to investigate the effects of the Mediterranean diet (MD), combined with curcumin and resveratrol supplementation, on disease activity, serum inflammatory markers, and quality of life in patients with mild-to-moderate active ulcerative colitis (UC). This study was designed as a prospective multicenter three-arm randomized controlled trial. Participants were randomized to the MD, MD + curcumin, and MD + resveratrol groups. All participants were placed on the MD for 8 weeks. The MD + curcumin group also received 1600 mg/day of curcumin supplementation, whereas the MD + resveratrol group received 500 mg/day of resveratrol supplementation for 8 weeks. Anthropometric measurements, Truelove-Witts Index, Short Form-36, Inflammatory Bowel Disease Questionnaire, Mediterranean Diet Adherence Scale (MEDAS), and laboratory tests were performed at baseline and postintervention. Within-group comparisons showed that MD, MD + curcumin, and MD + resveratrol interventions were effective in reducing disease activity and inflammation and improving quality of life in individuals with UC (p < 0.05). Between-group comparisons revealed no significant difference in all parameters except for the pain subparameter of SF-36 and the MEDAS score (p < 0.05). The MD is an effective and safe intervention to be used in clinical practice in individuals with UC.

Amelioration of Dextran Sodium Sulfate-Induced Colitis in Mice through Oral Administration of Palmitoylethanolamide

Inflammatory bowel disease (IBD) is a group of chronic disorders characterized by pain, ulceration, and the inflammation of the gastrointestinal tract (GIT) and categorized into two major subtypes: ulcerative colitis (UC) and Crohn's disease. The inflammation in UC is typically restricted to the mucosal surface, beginning in the rectum and extending through the entire colon. UC patients typically show increased levels of pro-inflammatory cytokines, leading to intestinal epithelial apoptosis and mucosal inflammation, which impair barrier integrity. Chronic inflammation is associated with the rapid recruitment and inappropriate retention of leukocytes at the site of inflammation, further amplifying the inflammation. While UC can be managed using a number of treatments, these drugs are expensive and cause unwanted side effects. Therefore, a safe and effective treatment for UC patients is needed. Palmitoylethanolamide (PEA) is an endogenous fatty acid amide and an analog of the endocannabinoid anandamine. PEA administration has been found to normalize intestinal GIT motility and reduce injury in rodents and humans. In the current study, we examined the efficacy of PEA encapsulated in phytosomes following oral administration in experimental ulcerative colitis. Here, we showed that PEA at a human-equivalent dose of 123 mg/kg (OD or BID) attenuated DSS-induced experimental colitis as represented by the reduction in clinical signs of colitis, reduction in gross mucosal injury, and suppression of leukocyte recruitment at inflamed venules. These findings add to the growing body of data demonstrating the beneficial effects of PEA to control the acute phase of intestinal inflammation occurring during UC.

Prebiotics for induction and maintenance of remission in ulcerative colitis

BACKGROUND

People affected by ulcerative colitis (UC) are interested in dietary therapies as treatments that can improve their health and quality of life. Prebiotics are a category of food ingredients theorised to have health benefits for the gastrointestinal system through their effect on the growth and activity of intestinal bacteria and probiotics.

OBJECTIVES

To assess the efficacy and safety of prebiotics for the induction and maintenance of remission in people with active UC.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, and WHO ICTRP on 24 June 2023.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) on people with UC. We considered any type of standalone or combination prebiotic intervention, except those prebiotics combined with probiotics (known as synbiotics), compared to any control intervention. We considered interventions of any dose and duration.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.

MAIN RESULTS

We included 9 RCTs involving a total of 445 participants. Study duration ranged from 14 days to 2 to 3 months for induction and 1 to 6 months for maintenance of remission. All studies were on adults. Five studies were on people with mild to moderate active disease, three in remission or mild activity, and one did not mention. We judged only one study as at low risk of bias in all areas. Two studies compared prebiotics with placebo for induction of remission. We cannot draw any conclusions about clinical remission (70% versus 67%; risk ratio (RR) 1.05, 95% confidence interval (CI) 0.57 to 1.94); clinical improvement (mean Rachmilewitz score on day 14 of 4.1 versus 4.5; mean difference (MD) -0.40, 95% CI -2.67 to 1.87); faecal calprotectin levels (mean faecal calprotectin on day 14 of 1211 μg/mL versus 3740 μg/mL; MD -2529.00, 95% CI -6925.38 to 1867.38); interleukin-8 (IL-8) levels (mean IL-8 on day 7 of 2.9 pg/mL versus 5.0 pg/mL; MD -2.10, 95% CI -4.93 to 0.73); prostaglandin E2 (PGE-2) levels (mean PGE-2 on day 7 of 7.1 ng/mL versus 11.5 ng/mL; MD -4.40, 95% CI -20.25 to 11.45); or withdrawals due to adverse events (21% versus 8%; RR 2.73, 95% CI 0.51 to 14.55). All evidence was of very low certainty. No other outcomes were reported. Two studies compared inulin and oligofructose 15 g with inulin and oligofructose 7.5 g for induction of remission. We cannot draw any conclusions about clinical remission (53% versus 12.5%; RR 4.27, 95% CI 1.07 to 16.96); clinical improvement (67% versus 25%; RR 2.67, 95% CI 1.06 to 6.70); total adverse events (53.5% versus 31%; RR 1.71, 95% CI 0.72 to 4.06); or withdrawals due to adverse events (13% versus 25%; RR 0.53, 95% CI 0.11 to 2.50). All evidence was of very low certainty. No other outcomes were reported. One study compared prebiotics and anti-inflammatory therapy with anti-inflammatory therapy alone for induction of remission. We cannot draw any conclusions about clinical improvement (mean Lichtiger score at 4 weeks of 6.2 versus 10.3; MD -4.10, 95% CI -8.14 to -0.06) or serum C-reactive protein (CRP) levels (mean CRP levels at 4 weeks 0.55 ng/mL versus 0.50 ng/mL; MD 0.05, 95% CI -0.37 to 0.47). All evidence was of very low certainty. No other outcomes were reported. Three studies compared prebiotics with placebo for maintenance of remission. There may be no difference between groups in rate of clinical relapse (44% versus 33%; RR 1.36, 95% CI 0.79 to 2.31), and prebiotics may lead to more total adverse events than placebo (77% versus 46%; RR 1.68, 95% CI 1.18 to 2.40). The evidence was of low certainty. We cannot draw any conclusions about clinical improvement (mean partial Mayo score at day 60 of 0.428 versus 1.625; MD -1.20, 95% CI -2.17 to -0.22); faecal calprotectin levels (mean faecal calprotectin level at day 60 of 214 μg/mL versus 304 μg/mL; MD -89.79, 95% CI -221.30 to 41.72); quality of life (mean Inflammatory Bowel Disease Questionnaire (IBDQ) score at day 60 of 193.5 versus 188.0; MD 5.50, 95% CI -8.94 to 19.94); or withdrawals due to adverse events (28.5% versus 11%; RR 2.57, 95% CI 1.15 to 5.73). The evidence for these outcomes was of very low certainty. No other outcomes were reported. One study compared prebiotics with synbiotics for maintenance of remission. We cannot draw any conclusions about quality of life (mean IBDQ score at 4 weeks 182.4 versus 176.1; MD 6.30, 95% CI -6.61 to 19.21) or withdrawals due to adverse events (23% versus 20%; RR 1.13, 95% CI 0.48 to 2.62). All evidence was of very low certainty. No other outcomes were reported. One study compared prebiotics with probiotics for maintenance of remission. We cannot draw any conclusions about quality of life (mean IBDQ score at 4 weeks 182.4 versus 168.6; MD 13.60, 95% CI 1.22 to 25.98) or withdrawals due to adverse events (22.5% versus 22.5%; RR 1.00, 95% CI 0.44 to 2.26). All evidence was of very low certainty. No other outcomes were reported.

AUTHORS' CONCLUSIONS

There may be no difference in occurrence of clinical relapse when adjuvant treatment with prebiotics is compared with adjuvant treatment with placebo for maintenance of remission in UC. Adjuvant treatment with prebiotics may result in more total adverse events when compared to adjuvant treatment with placebo for maintenance of remission. We could draw no conclusions for any of the other outcomes in this comparison due to the very low certainty of the evidence. The evidence for all other comparisons and outcomes was also of very low certainty, precluding any conclusions. It is difficult to make any clear recommendations for future research based on the findings of this review given the clinical and methodological heterogeneity among studies. It is recommended that a consensus is reached on these issues prior to any further research.

Anemoside B4 ameliorates dextran sulfate sodium (DSS)-induced colitis through inhibiting NLRP3 inflammasome and modulating gut microbiota

Ulcerative colitis (UC) has been recognized as a chronic and relapsing inflammatory disease of the gastrointestinal tract. Clinically, aminosalicylates, immunosuppressants and biological agents are commonly used to treat UC at different stages of the disease. However, these drugs often have side effects. Here, we investigated the anti-UC activity of Anemoside B4 (AB4) in mice with dextran sulfate sodium (DSS) induced colitis. Colon tissues, serum, and colonic contents were collected for assessment of intestinal barrier function, inflammatory cytokines production and microenvironment of intestinal microbiota. Results showed that AB4 alleviated colon shortening, weight lossing and histopathological damage in DSS-induced mice. In addition, we demonstrated both in vivo and in vitro that AB4 remarkably ameliorated colonic inflammation through suppressing NLRP3 pathway. Moreover, AB4 strengthened the intestinal epithelial barrier by regulating myosin light chain kinase (MLCK)-phosphorylated myosin light chain 2 (pMLC2) signaling pathway. Furthermore, we performed 16 S rRNA gene sequencing and fecal microbiome transplantation (FMT) experiments to demonstrate that AB4 alleviated colitis through regulating dysbiosis of intestinal microbiota. These results revealed that AB4 effectively ameliorate experimental UC mainly through regulating MLCK/pMLC2 pathway, NLRP3 pathway and dysbiosis of microbiota, provided new insights into the development of novel anti-UC drugs.

The INHABIT (synergIstic effect of aNtHocyAnin and proBIoTics in) Inflammatory Bowel Disease trial: a study protocol for a double-blind, randomised, controlled, multi-arm trial

Ulcerative Colitis (UC), a type of Inflammatory Bowel Disease (IBD), is a chronic, relapsing gastrointestinal condition with increasing global prevalence. The gut microbiome profile of people living with UC differs from healthy controls and this may play a role in the pathogenesis and clinical management of UC. Probiotics have been shown to induce remission in UC; however, their impact on the gut microbiome and inflammation is less clear. Anthocyanins, a flavonoid subclass, have shown anti-inflammatory and microbiota-modulating properties; however, this evidence is largely preclinical. To explore the combined effect and clinical significance of anthocyanins and a multi-strain probiotic, a 3-month randomised controlled trial will be conducted in 100 adults with UC. Participants will be randomly assigned to one of four groups: anthocyanins (blackcurrant powder) + placebo probiotic, probiotic + placebo fruit powder, anthocyanin + probiotic, or double placebo. The primary outcome is a clinically significant change in the health-related quality-of-life measured with the Inflammatory Bowel Disease Questionnaire-32. Secondary outcomes include shotgun metagenomic sequencing of the faecal microbiota, faecal calprotectin, symptom severity, and mood and cognitive tests. This research will identify the role of adjuvant anti-inflammatory dietary treatments in adults with UC and elucidate the relationship between the gut microbiome and inflammatory biomarkers in this disease, to help identify targeted individualised microbial therapies. ANZCTR registration ACTRN12623000630617.

Lasso peptide MccY alleviates non-typhoidal salmonellae-induced mouse gut inflammation via regulation of intestinal barrier function and gut microbiota

IMPORTANCE

Diseases caused by Enterobacteriaceae multidrug-resistant strains have become increasingly difficult to manage. It is necessary to verify the new antibacterial drug MccY effect on non-typhoid Salmonella infection in mice since it is regarded as a promising microcin. The results demonstrated that MccY has a potential therapeutic application value in the protection against Salmonella-induced intestinal damage and alleviating related intestinal dysbiosis and metabolic disorders. MccY could be a promising candidate as an antimicrobial or anti-inflammatory agent for treating infectious diseases.

Cotinus coggygria Scop. Attenuates Acetic Acid-Induced Colitis in Rats by Regulation of Inflammatory Mediators

In traditional medicine, many medicinal plants are used in the treatment of various diseases caused by inflammation. The objective of the present study is to elucidate for the first time the effects of Cotinus coggygria (CC) ethanol extract (CCE) on colonic structure and inflammation of acetic acid-induced ulcerative colitis in rats. Colonic damage was assessed using disease activity index score, enzyme-linked immunosorbent assay, and hematoxylin-eosin staining. Also, in vitro antioxidant activity of CCE was investigated by ABTS methods. Total phytochemical content of CCE was measured spectroscopically. Acetic acid caused colonic damage according to disease activity index and macroscopic scoring. CCE significantly reversed these damages. While the levels of proinflammatory cytokines TNF-alpha, IL-1beta, IL-6, and TGF-1beta increased in tissue with UC, IL-10 level decreased. CCE increased inflammatory cytokine levels to values close to the sham group. At the same time, while markers indicating disease severity such as VEGF, COX-2, PGE2, and 8-OHdG indicated the disease in the colitis group, these values returned to normal with CCE. Histological research results support biochemical analysis. CCE exhibited significant antioxidant against ABTS radical. Also, CCE was found to have a high content of total polyphenolic compounds. These findings provide evidence that CCE might be benefit as a promising novel therapy in the treatment of UC in humans due to high polyphenol content and justify the use of CC in folkloric medicine for treatment of inflamed diseases.

Mechanistic insights into the role of probiotics in modulating immune cells in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a persistent inflammatory disorder that affects the gastrointestinal tract, mainly the colon, which is defined by inflammatory responses and the formation of ulcers. Probiotics have been shown to directly impact various immune cells, including dendritic cells (DCs), macrophages, natural killer (NK) cells, and T and B cells. By interacting with cell surface receptors, they regulate immune cell activity, produce metabolites that influence immune responses, and control the release of cytokines and chemokines.

METHODS

This article is a comprehensive review wherein we conducted an exhaustive search across published literature, utilizing reputable databases like PubMed and Web of Science. Our focus centered on pertinent keywords, such as "UC," 'DSS," "TNBS," "immune cells," and "inflammatory cytokines," to compile the most current insights regarding the therapeutic potential of probiotics in managing UC.

RESULTS

This overview aims to provide readers with a comprehensive understanding of the effects of probiotics on immune cells in relation to UC. Probiotics have a crucial role in promoting the proliferation of regulatory T cells (Tregs), which are necessary for preserving immunological homeostasis and regulating inflammatory responses. They also decrease the activation of pro-inflammatory cells like T helper 1 (Th1) and Th17 cells, contributing to UC development. Thus, probiotics significantly impact both direct and indirect pathways of immune cell regulation in UC, promoting Treg differentiation, inhibiting pro-inflammatory cell activation, and regulating cytokine and chemokine release.

CONCLUSION

Probiotics demonstrate significant potential in modulating the immune reactions in UC. Their capacity to modulate different immune cells and inflammation-related processes makes them a promising therapeutic approach for managing UC. However, further studies are warranted to optimize their use and fully elucidate the molecular mechanisms underlying their beneficial effects in UC treatment.

N-Acetylglucosamine and its dimer ameliorate inflammation in murine colitis by strengthening the gut barrier function

Ulcerative colitis (UC) is a chronic gastrointestinal disease whose incidence is increasing rapidly worldwide. Anti-inflammatory medications, including 5-aminosalicylic acid (5-ASA), corticosteroids, and immunosuppressants, are used for its treatment; however, new alternatives would be required due to the serious side effects of some of these medications. N-Acetylglucosamine (NAG) is an amino sugar composed of mucin that is secreted by intestinal epithelial cells. It is also used to promote the growth of intestinal bacteria. The current study aimed to determine the efficacy of NAG against dextran sulfate sodium (DSS)-induced chronic colitis and elucidate its mechanism of action. Mice were randomly divided into control, DSS, 0.1% sulfasalazine, 0.1% NAG, 0.3% NAG, and 0.3% NAG-dimer (NAG-D) groups, and results showed that colitis-induced body weight loss, disease activity, colonic tissue damage, colon length shortening, and the loss of mucin-secreting area were significantly improved in the NAG-D group. The intestinal permeability indicator, serum CD 14 level, and expression of the tight junction protein, occludin, were both improved in the 0.3% NAG group. Inflammatory biomarkers, including GATA3, IFN-γ, p-IκBα, COX2, TGF-β1, and Smad7, were significantly lower in the 0.3% NAG and NAG-D groups than in the DSS group. The intestinal microbial composition was most significantly altered in the 0.3% NAG group, showing decreased ratios of pathogenic bacteria, such as Betaproteobacteria, especially Burkholderiales. The results overall suggested that NAG or NAG-D supplementation can alleviate inflammation by strengthening the intestinal barrier function and maintaining gut microbiota homeostasis in a DSS-induced colitis mouse model.

Epithelial Ca2+ waves triggered by enteric neurons heal the gut

A fundamental and unresolved question in regenerative biology is how tissues return to homeostasis after injury. Answering this question is essential for understanding the etiology of chronic disorders such as inflammatory bowel diseases and cancer. We used the Drosophila midgut to investigate this question and discovered that during regeneration a subpopulation of cholinergic enteric neurons triggers Ca2+ currents among enterocytes to promote return of the epithelium to homeostasis. Specifically, we found that down-regulation of the cholinergic enzyme Acetylcholinesterase in the epithelium enables acetylcholine from defined enteric neurons, referred as ARCENs, to activate nicotinic receptors in enterocytes found near ARCEN-innervations. This activation triggers high Ca2+ influx that spreads in the epithelium through Inx2/Inx7 gap junctions promoting enterocyte maturation followed by reduction of proliferation and inflammation. Disrupting this process causes chronic injury consisting of ion imbalance, Yki activation and increase of inflammatory cytokines together with hyperplasia, reminiscent of inflammatory bowel diseases. Altogether, we found that during gut regeneration the conserved cholinergic pathway facilitates epithelial Ca2+ waves that heal the intestinal epithelium. Our findings demonstrate nerve- and bioelectric-dependent intestinal regeneration which advance the current understanding of how a tissue returns to its homeostatic state after injury and could ultimately help existing therapeutics.

Intracellular DNA sensing by neutrophils and amplification of the innate immune response

As the first responders, neutrophils lead the innate immune response to infectious pathogens and inflammation inducing agents. The well-established pathogen neutralizing strategies employed by neutrophils are phagocytosis, the action of microbicide granules, the production of ROS, and the secretion of neutrophil extracellular traps (NETs). Only recently, the ability of neutrophils to sense and respond to pathogen-associated molecular patterns is being appreciated. This review brings together the current information about the intracellular recognition of DNA by neutrophils and proposes models of signal amplification in immune response. Finally, the clinical relevance of DNA sensing by neutrophils in infectious and non-infectious diseases including malignancy are also discussed.

Mirabegron alleviates acetic acid-induced colitis in rats: role of adiponectin and GSTM1/GSH detoxification pathway

The prevalence of the debilitating chronic disease ulcerative colitis (UC) is increasing significantly. Mirabegron is a selective beta-3 adrenergic receptor (β-3 AR) agonist used to treat an overactive bladder. Previous reports have demonstrated the antidiarrheal effect of β-3AR agonists. Therefore, the current study aims to investigate the potential symptomatic effects of mirabegron on an experimental colitis model. The effects of oral administration of mirabegron (10mg/kg) for seven days on rats receiving intra-rectal acetic acid instillation on the sixth day were examined using adult male Wistar rats. Sulfasalazine was utilized as a reference medication. Gross, microscopic, and biochemical observations of the experimental colitis were performed. The quantity and mucin content of goblet cells were found to have significantly decreased in the colitis group. In the colons of rats administered mirabegron, the number of goblet cells and the optical density of its mucin content increased. Mirabegron's ability to increase adiponectin in serum and decrease glutathione, GSTM1, and catalase in the colon may account for its protective effects. In addition, mirabegron decreased the expression of the proteins caspase-3 and NF-κB p65. It also prevented the activation of their upstream signaling receptors TLR4 and p-AKT by acetic acid administration. In conclusion, mirabegron prevented acetic acid-induced colitis in rats, possibly due to its antioxidant, anti-inflammatory, and antiapoptotic properties.

Circulating Profiles of Serum Proguanylin, S100A12 Protein and Pentraxin 3 as Diagnostic Markers of Ulcerative Colitis

The aim of this research was to investigate potential new biomarkers which could be used in the clinical practice of ulcerative colitis (UC). Given the crucial role of intestinal barrier integrity and inflammation in the pathogenesis of UC, the serum profile of proteins linked to intestinal barrier and pro-inflammatory neutrophil products may be useful in diagnosing and monitoring the activity of the disease. We measured serum levels of proguanylin (pro-GN), S100A12, and pentraxin 3 (PTX3) in 31 patients with UC before and after a year of biological treatment, as well as in 20 healthy individuals. Significant differences in the serum profiles of pro-GN (5.27 vs. 11.35, p < 0.001), S100A12 (39.36 vs. 19.74, p < 0.001) and PTX3 (3197.05 vs. 1608.37, p < 0.001) were observed between pre-treatment patients with UC and healthy individuals. Furthermore, in UC patients prior to treatment, the levels of S100A12 (p < 0.0005; r = 0.628) and PTX3 (p < 0.05; r = 0.371) were correlated with disease activity as measured by the Mayo scale. Following a year of biological treatment with adalimumab, the concentration of pro-GN significantly increased (5.27 vs. 6.68, p < 0.005) in the blood of UC patients, while the level of PTX-3 decreased (3197.05 vs. 1946.4, p < 0.0001). Our study demonstrates the usefulness of pro-GN, S100A12, and PTX3 measurements in diagnosing and monitoring the activity of UC.

2'-Fucosyllactose and 3-Fucosyllactose Alleviates Interleukin-6-Induced Barrier Dysfunction and Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Modulating the Intestinal Microbiome

Ulcerative colitis is an inflammatory bowel disease (IBD) with relapsing and remitting patterns, and it is caused by varied factors, such as the intestinal inflammation extent and duration. We examined the preventative effects of human milk oligosaccharides (HMOs) on epithelial barrier integrity and intestinal inflammation in an interleukin (IL)-6-induced cell model and dextran sodium sulfate (DSS)-induced acute mouse colitis model. HMOs including 2'-fucosyllactose (FL) and 3-FL and positive controls including fructooligosaccharide (FOS) and 5-acetylsalicylic acid (5-ASA) were orally administrated once per day to C57BL/6J mice with colitis induced by 5% DSS in the administered drinking water. 2'-FL and 3-FL did not affect the cell viability in Caco-2 cells. Meanwhile, these agents reversed IL-6-reduced intestinal barrier function in Caco-2 cells. Furthermore, 2'-FL and 3-FL reversed the body weight loss and the remarkably short colon lengths in DSS-induced acute colitis mice. Moreover, 2'-FL and 3-FL obviously protected the decreasing expression of zonula occluden-1 and occludin in colon tissue relative to the findings in the DSS-treated control group. 2'-FL and 3-FL significantly reduced IL-6 and tumor necrosis factor-α levels in serum relative to the control findings. The summary of these results shows that HMOs prevent colitis mainly by enhancing intestinal barrier function and advancing anti-inflammatory responses. Therefore, HMOs might suppress inflammatory responses and represent candidate treatments for IBD that protect intestinal integrity.

Beneficial Effects of Hordenine on a Model of Ulcerative Colitis

Hordenine, a phenethylamine alkaloid, is found in a variety of plants and exhibits a broad array of biological activities and pharmacological properties, including anti-inflammatory and anti-fibrotic effects. However, the efficacy and underlying mechanisms of hordenine in treating ulcerative colitis (UC) remain unclear. To address this, we examined the therapeutic effects of hordenine on dextran sodium sulphate (DSS)-induced UC by comparing disease activity index (DAI), colon length, secretion of inflammatory factors, and degree of colonic histological lesions across diseased mice that were and were not treated with hordenine. We found that hordenine significantly reduced DAI and levels of pro-inflammatory factors, including interleukin (IL)-6, IL-1β, and tumor necrosis factor alpha (TNF-α), and also alleviated colon tissue oedema, colonic lesions, inflammatory cells infiltration and decreased the number of goblet cells. Moreover, in vitro experiments showed that hordenine protected intestinal epithelial barrier function by increasing the expression of tight junction proteins including ZO-1 and occludin, while also promoting the healing of intestinal mucosa. Using immunohistochemistry and western blotting, we demonstrated that hordenine reduced the expression of sphingosine kinase 1 (SPHK1), sphingosine-1-phosphate receptor 1 (S1PR1), and ras-related C3 botulinum toxin substrate 1 (Rac1), and it inhibited the expression of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in colon tissues. Thus, hordenine appears to be effective in UC treatment owing to pharmacological mechanisms that favor mucosal healing and the inhibition of SPHK-1/S1PR1/STAT3 signaling.

Imatinib mitigates experimentally-induced ulcerative colitis: Possible contribution of NF-kB/JAK2/STAT3/COX2 signaling pathway

RATIONALE

Ulcerative colitis (UC) is a chronic immune-mediated disease characterized by recurrent inflammation, damage, and alteration of the large intestine's mucosal and submucosal surfaces. The purpose of this research was to evaluate the impact of tyrosine kinase inhibitor (imatinib) on experimentally induced UC in rats via acetic acid (AA).

METHODS

Male rats were randomly assigned to four groups: control, AA, AA + imatinib (10 mg/kg), and AA + imatinib (20 mg/kg). Imatinib (10 and 20 mg/kg/day) was orally supplied by oral syringe for one week before induction of UC. On the eighth day, Rats received enemas containing a 4 % solution of acetic acid to induce colitis. One day after inducing colitis, rats were euthanized and their colons were subjected to morphological, biochemical, histological, and immunohistochemical analysis.

RESULTS

Imatinib pretreatment significantly decreased macroscopic and histological damage scores, decreased disease activity index as well as colon mass index. In addition, imatinib successfully lowered the levels of malondialdehyde (MDA) in colonic tissues and enhanced superoxide dismutase activity (SOD) and glutathione content (GSH). Imatinib also reduced colonic levels of inflammatory interleukins (IL-23, IL-17, IL-6), JAK2 and STAT3. Furthermore, imatinib suppressed nuclear transcription factor kappa B (NF-kB/p65) level, and COX2 expression in colonic tissues.

SIGNIFICANCE

Imatinib may be a viable therapy option for UC as it halts the interaction network of NF-kB/JAK2/STAT3/COX2 signaling pathway.

Qingre Xingyu recipe exerts inhibiting effects on ulcerative colitis development by inhibiting TNFα/NLRP3/Caspase-1/IL-1β pathway and macrophage M1 polarization

As a chronic inflammatory bowel disease, ulcerative colitis (UC) imposes a significant burden on public healthcare worldwide due to its increasing morbidity. Chinese medicines are regarded as potent therapeutic agents for UC treatment with minimal side effects. In the present study, we sought to determine the novel role of a traditional medicine Qingre Xingyu (QRXY) recipe in the development of UC and aimed to contribute to the currently available knowledge about UC by exploring the downstream mechanism of QRXY recipe in UC. Mouse models of UC were established by injections with dextran sulphate sodium (DSS), where the expression of tumor necrosis factor-alpha (TNFα), NLR family pyrin domain containing 3 (NLRP3), and interleukin-1β (IL-1β) was determined followed by an analysis of their interactions. The DSS-treated NLRP3 knockout (^-/-) Caco-2 cell model was successfully constructed. The in vitro and in vivo effects of the QRXY recipe on UC were investigated with the determination of disease activity index (DAI), histopathological scores, transepithelial electrical resistance, FITC-dextran, as well as cell proliferation and apoptosis. In vivo and in vitro experiments indicated that the QRXY recipe reduced the degree of intestinal mucosal injury of UC mice and functional damage of DSS-induced Caco-2 cells by inhibition of the TNFα/NLRP3/caspase-1/IL-1β pathway and M1 polarization of macrophages, and TNFα overexpression or NLRP3 knockdown could counterweigh the therapeutic effects of QRXY recipe. To conclude, our study elicited that QRXY inhibited the expression of TNFα and inactivated the NLRP3/Caspase-1/IL-1β pathway, thereby alleviating intestinal mucosal injury and relieving UC in mice.

Nuciferine alleviates intestinal inflammation by inhibiting MAPK/NF-κB and NLRP3/Caspase 1 pathways in vivo and in vitro

Nuciferine (NCF) is an aporphine alkaloid and a principal bioactive constituent in the lotus plant. Herewith, we investigated the potential anti-inflammatory effect and underlying mechanisms of NCF employing dextran sulfate sodium (DSS)-induced ulcerative colitis in mice, a predominant intestinal inflammatory disease, and mouse RAW 264.7 cells in vitro. Lipopolysaccharide (LPS) was used to generate an inflammatory response in the RAW 264.7 cells. The disease activity index (DAI), colon morphology, colonoscopy, and colon histopathology were performed to assess experimental colitis. The biochemical assays, enzyme-linked immunosorbent assay (ELISA), and immunoblot analysis were performed to understand the underlying mechanisms. In RAW 264.7 cells, NCF pretreatment significantly decreased the expression of inducible nitric oxide synthase (iNOS), the expression and release of pro-inflammatory cytokines including interleukin (IL)-1β, IL-18, and tumor necrosis factor-α (TNF-α) and interfered with the activation of mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), and NOD-like family pyrin domain containing 3 (NLRP3) signaling pathways. The oral treatment of NCF substantially alleviated the DSS-induced DAI, increased colon length, and restored colon morphology and histology. Compared to the DSS-induced mice, the proteins involved in the activation of MAPK/NF-κB/NLRP3 pathways and the cytokines were markedly decreased in the NCF-treated mice. Moreover, the tight junction architecture of the colon was well-maintained in NCF treatment groups by regulating the expression of claudin-1 and zonula occludens-1 (ZO-1) proteins. All these findings suggest that NCF can be a promising molecule to modulate ulcerative colitis.

Pathophysiology of Inflammatory Bowel Disease: Innate Immune System

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is a heterogeneous state of chronic intestinal inflammation with no exact known cause. Intestinal innate immunity is enacted by neutrophils, monocytes, macrophages, and dendritic cells (DCs), and innate lymphoid cells and NK cells, characterized by their capacity to produce a rapid and nonspecific reaction as a first-line response. Innate immune cells (IIC) defend against pathogens and excessive entry of intestinal microorganisms, while preserving immune tolerance to resident intestinal microbiota. Changes to this equilibrium are linked to intestinal inflammation in the gut and IBD. IICs mediate host defense responses, inflammation, and tissue healing by producing cytokines and chemokines, activating the complement cascade and phagocytosis, or presenting antigens to activate the adaptive immune response. IICs exert important functions that promote or ameliorate the cellular and molecular mechanisms that underlie and sustain IBD. A comprehensive understanding of the mechanisms underlying these clinical manifestations will be important for developing therapies targeting the innate immune system in IBD patients. This review examines the complex roles of and interactions among IICs, and their interactions with other immune and non-immune cells in homeostasis and pathological conditions.

Green tea EGCG effectively alleviates experimental colitis in middle-aged male mice by attenuating multiple aspects of oxi-inflammatory stress and cell cycle deregulation

Age-dependent increased risk of inflammatory bowel diseases such as ulcerative colitis is being increasingly realized, and yet therapies targeting this disorder within the purview of aging are limited. The present study attempted to assess the efficacy of green tea epigallocatechin gallate (EGCG) consumption in preventing the severity and progression of dextran sulphate sodium (DSS)-induced ulcerative colitis in 18 months old middle-aged male mice. Acute colitis was induced in animals using DSS and protective effects of EGCG consumption were examined. Different parameters related to disease progression and molecular markers related to oxi-inflammatory stress, localized and systemic cytokine response, epithelial barrier integrity, and cell cycle progression profile were evaluated. DSS treatment induced rapid and severe symptoms of colitis such as consistently increased DAI score, shortened and inflamed colon accompanied by increased levels of inflammatory proteins (TNFα/IL-6/IL-1β) in both the colon tissue and cultured splenocytes indicating exaggerated Th1 immune response. Markers of oxidative stress increased while antioxidant defences and the expression of tight junction genes in the colonic cells were attenuated. Dysregulation in the expression of cell cycle inhibitory genes (p53/p21^WAF1/p16^Ink4a) indicated possible induction of colitis-induced dysplasia. On the other hand, EGCG consumption strongly attenuated all the measured ostensible as well as molecular markers of the disease progression as evidenced by improved DAI score, cellular antioxidant capacity, attenuated Th1 cytokine response both in the colon and cultured splenocytes, enhanced expression of tight junction genes, and cell cycle inhibitors thereby suggesting systemic effects of EGCG. Together, these observations suggest that drinking EGCG-rich green tea can be a significant way of managing the severity of colitis during aging.

The Prevalence of Ocular Extra-Intestinal Manifestations in Adults Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Patients with inflammatory bowel disease (IBD) have a greater frequency of ocular extra-intestinal manifestations (O-EIMs) than the general population, while Crohn's disease (CD) and ulcerative colitis (UC) have inconsistent prevalence, according to previous studies. This study aimed to examine the prevalence of O-EIMs in CD and UC, respectively. We systemically reviewed O-EIMs and IBD across several online databases. Inclusion criteria are as follows: (1) observational studies examining the association between O-EIMs and IBD, such as cross-sectional, case-control, or cohort studies; (2) human and adult individuals; and (3) with case and control groups consisting of patients with and without O-EIMs, respectively. Patients under the age of 18 or any study on pediatric IBD will be excluded. The prevalence of uveitis in adults was determined by 21 studies comprising 190,941 individuals with IBD, including 62,874 CD and 128,067 UC. The pooled analysis revealed significantly increased odds of uveitis in patients with CD than with UC (pooled odd ratio (OR) 1.603, 95% confidence interval 1.254-2.049). The subgroup analysis revealed that European populations had significantly higher odds of developing uveitis and episcleritis in patients with CD than UC (pooled OR 1.683 and 2.401, respectively). Although O-EIMs may be the prodrome of IBD, no consistent finding was obtained as a result of the high heterogeneity from the two included studies. This meta-analysis indicates the significantly increased odds of uveitis in adults with CD than those with UC. In subgroup analysis, European with CD seemed to have higher odds of uveitis and episcleritis than those with UC. Nonetheless, the link between O-EIMs and IBD remained unclear.

Comprehensive Phenotyping in Inflammatory Bowel Disease: Search for Biomarker Algorithms in the Transkingdom Interactions Context

Inflammatory bowel disease (IBD) is the most common form of intestinal inflammation associated with a dysregulated immune system response to the commensal microbiota in a genetically susceptible host. IBD includes ulcerative colitis (UC) and Crohn’s disease (CD), both of which are remarkably heterogeneous in their clinical presentation and response to treatment. This translates into a notable diagnostic challenge, especially in underdeveloped countries where IBD is on the rise and access to diagnosis or treatment is not always accessible for chronic diseases. The present work characterized, for the first time in our region, epigenetic biomarkers and gut microbial profiles associated with UC and CD patients in the Buenos Aires Metropolitan area and revealed differences between non-IBD controls and IBD patients. General metabolic functions associated with the gut microbiota, as well as core microorganisms within groups, were also analyzed. Additionally, the gut microbiota analysis was integrated with relevant clinical, biochemical and epigenetic markers considered in the follow-up of patients with IBD, with the aim of generating more powerful diagnostic tools to discriminate phenotypes. Overall, our study provides new insights into data analysis algorithms to promote comprehensive phenotyping tools using quantitative and qualitative analysis in a transkingdom interactions network context.

Mitochondria-Targeted Antioxidant SkQ1 Prevents the Development of Experimental Colitis in Mice and Impairment of the Barrier Function of the Intestinal Epithelium

Mitochondria-targeted antioxidants have become promising candidates for the therapy of various pathologies. The mitochondria-targeted antioxidant SkQ1, which is a derivative of plastoquinone, has been successfully used in preclinical studies for the treatment of cardiovascular and renal diseases, and has demonstrated anti-inflammatory activity in a number of inflammatory disease models. The present work aimed to investigate the therapeutic potential of SkQ1 and C12TPP, the analog of SkQ1 lacking the antioxidant quinone moiety, in the prevention of sodium dextran sulfate (DSS) experimental colitis and impairment of the barrier function of the intestinal epithelium in mice. DSS-treated animals exhibited weight loss, bloody stool, dysfunction of the intestinal epithelium barrier (which was observed using FITC-dextran permeability), reduced colon length, and histopathological changes in the colon mucosa. SkQ1 prevented the development of clinical and histological changes in DSS-treated mice. SkQ1 also reduced mRNA expression of pro-inflammatory molecules TNF, IL-6, IL-1β, and ICAM-1 in the proximal colon compared with DSS-treated animals. SkQ1 prevented DSS-induced tight junction disassembly in Caco-2 cells. Pretreatment of mice by C12TPP did not protect against DSS-induced colitis. Furthermore, C12TPP did not prevent DSS-induced tight junction disassembly in Caco-2 cells. Our results suggest that SkQ1 may be a promising therapeutic agent for the treatment of inflammatory bowel diseases, in particular ulcerative colitis.

Ectopically Localized Epithelial Cell Clumps in Ulcers Are Derived from Reserved Crypt Stem Cells in a Mouse Model of Ulcerative Colitis

BACKGROUND

We previously reported that clumps of a few epithelial cells were scattered in ulcer regions in a dextran sulfate sodium (DSS)-induced mouse model of ulcerative colitis (UC).

AIMS

To determine the ectopically localized epithelial clumps might be derived from stem cells or their daughter progenitor cells.

METHODS

Female BALB/c mice were administered DSS in drinking water for 6 days, followed by withdrawal of DSS for 6 days. Histological and immunohistochemical examinations were conducted in the distal region and proximal region of the colorectum to determine expression of stem cell markers in the epithelial clumps.

RESULTS

Similar to the characteristics of UC, the ulcers were more severe in the distal region close to the anus than in the proximal region of the colorectum. Quantitative analyses revealed that the epithelial clumps appeared in relation to the severity of the ulcer, and they expressed the cell adhesion molecules E-cadherin and β-catenin. Among stem cell markers, the epithelial clumps primarily expressed +5 cell marker Dll1 as reserved intestinal stem cells, followed by +4 cell marker Bmi1 and crypt stem cell marker Lgr5 in that order. Nuclear expression of Sox9, but not nuclear β-catenin, was identified in the clumps.

CONCLUSION

The present results suggest that most epithelial clumps comprised crypt-derived, reserved stem cells, which might have potential for mucosal healing.

Anti-inflammatory effects of β-ionone-curcumin hybrid derivatives against ulcerative colitis

A series of β-ionone-curcumin hybrid derivatives were designed and chosen to merge the biological characteristics of two parent molecules and to obtain a leading compound with higher biological activity. Through the initial screening, the structure activity relationship of their hybrid derivatives as inhibitors of nitric oxide (NO) production showed that meta-substituted derivatives exhibited the best inhibitory activity, among which 1h was the best one. In lipopolysaccharide-induced Raw264.7 macrophage cells, 1h showed anti-inflammatory activity by inhibiting the productions of NO and reactive oxygen species, the expressions of Interleukin-1β and tumor necrosis factor-α, and the translocation of nuclear factor (NF)-κB from the cytosol to the nucleus. Furthermore, molecular docking simulation displayed that 1h could interact with cluster of differentiation 14 to inhibit the toll-like receptor 4/NF-κB signaling. In dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) of mice, 100 mg/kg of 1h could significantly reduce the colon length shortening and protect against colon injury, liver injury and oxidative stress in DSS-induced UC of mice. Besides, 1h was safety in vivo. In conclusion, 1h was the potential anti-inflammatory agent, and further investigations were underway in our laboratory.

Astragaloside Ⅳ alleviates ulcerative colitis by regulating the balance of Th17/Treg cells

BACKGROUND

Restoring immune homeostasis by targeting the Th17/Treg response is a potentially valuable therapeutic strategy for ulcerative colitis (UC). Astragaloside IV (AS-Ⅳ) is a phytochemical naturally occurring in Astragalus membranaceus that has good anti-inflammatory, anti-oxidant and anti-stress properties. However, the effects of AS-IV on the homeostasis of Th17/Treg cells in colitis mice remains unknown.

PURPOSE

To investigate the protective effects and potential immunomodulatory mechanisms of AS-IV on UC.

METHODS

This study was constructed for DSS-induced acute colitis and recurrent colitis, with AS-IV administered prophylactically and therapeutically, respectively. The balance of Th17/Treg cells was analyzed by flow cytometry, their specific nuclear transcription factors were detected by RT-PCR as well as their secreted inflammatory cytokines were detected by ELISA and RT-PCR. Notch signaling-related proteins were detected by RT-PCR and Western blotting. Oxidative stress indicators were measured by biochemical technology.

RESULTS

In this study, AS-IV treatment not only effectively prevented and alleviated the clinical symptoms of DSS-induced colitis mice, including weight loss, DAI soaring, colon length shortening and colon weight gain, but also significantly improved ulcer formation, inflammatory cell infiltration and index, and regulated the expression of inflammatory cytokines in colon tissues. Importantly, the efficacy of high-dose AS-IV (100 mg/kg/day) in mice with recurrent colitis in this study was comparable to that of 5-ASA. AS-IV early administration was able to reshape the homeostasis of Th17/Treg cells in mice with acute colitis; meanwhile, AS-IV inhibited Th17 cell responses and promoted Treg cell responses in mice with recurrent colitis. Moreover, AS-IV not only inhibited the activation of Notch signaling pathway in colitis mice, but also prevented and ameliorated DSS-induced oxidative stress injury.

CONCLUSION

In conclusion, AS-IV effectively prevented and alleviated UC by reshaping Th17/Treg cell homeostasis and anti-oxidative stress.

Anti-Inflammatory Effects of Aralia elata Extract Against Dextran Sodium Sulfate-Induced Colitis in Mice and Raw 264.7 Macrophage Cells Exposed to Lipopolysaccharide: First Report

Aralia elata (AE) is an anti-inflammatory, polyphenolic containing medicinal plant. However, little is known about AE and its application to ulcerative colitis (UC). This study aimed to confirm AE extract's antioxidant and anti-inflammatory effects in vivo and in vitro. The in vitro antioxidant activity was evaluated by measuring total polyphenol and flavonoid content in AE extract. AE extract (10 000 mg/L) contained 186.8 mg GAE/g polyphenol and 81.9 mg QE/g flavonoid. Mice were divided into 6 groups, including control, which received normal saline, and treatment groups, which received dextran sodium sulfate (DSS) with or without AE extract (250, 500, and 1000 mg/kg). RAW 264.7 macrophage cells were divided into 2 groups: control and treatment. RAW 264.7 macrophage cells treated with sterile double distilled water, 1 mg/L lipopolysaccharide (LPS), and AE extracts (25, 50, 75, 100 µg/mL) were used to assess the cytotoxicity and anti-inflammatory activity. High-performance liquid chromatography, enzyme-linked immunosorbent assay (ELISA) kits, and histology were employed to analyze the AE extract contents, nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6, as oxidative stress markers. In addition, the disease activity index (DAI) and cytotoxicity were determined in mice and cells, respectively. High-performance liquid chromatography analysis revealed that AE extract is rich in chlorogenic acid (96 ± 0.01 mg/g). DSS increased the DAI and levels of TNF-α, IL-1β, and immune cell infiltration compared with those of the control animals. Furthermore, LPS eventually reduced cell viability and increased the levels of NO, TNF-α, IL-1β, and IL-6 in contrast to control cells. After treatment, a noticeable reduction was observed in the levels of DAI, NO, TNF-α, IL-1β, and IL-6 compared to those without AE treatments. Overall, AE extract is safe and had anti-inflammatory properties. Therefore, AE extract can be considered a potential pre-treatment supplement for UC.

Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression?

Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.

Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression?

Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.

Epigenetic DNA methylation of Zbtb7b regulates the population of double-positive CD4+CD8+ T cells in ulcerative colitis

BACKGROUND AND AIMS

Ulcerative colitis (UC) is a heterogeneous disorder with complex pathogenesis. Therefore, in the present study, we aimed to assess genome-wide DNA methylation changes associated explicitly with the pathogenesis of UC.

METHODS

DNA methylation changes were identified by comparing UC tissues with healthy controls (HCs) from the GEO databases. The candidate genes were obtained and verified in clinical samples. Moreover, the underlying molecular mechanism related to Zbtb7b in the pathogenesis of UC was explored using the dextran sodium sulfate (DSS)-induced colitis model.

RESULTS

Bioinformatic analysis from GEO databases confirmed that Zbtb7b, known as Th-inducing POZ-Kruppel factor (ThPOK), was demethylated in UC tissues. Then, we demonstrated that Zbtb7b was in a hypo-methylation pattern through the DSS-induced colitis model (P = 0.0357), whereas the expression of Zbtb7b at the mRNA and protein levels was significantly up-regulated in the inflamed colonic tissues of UC patients (qRT-PCR, WB, IHC: P < 0.0001, P = 0.0079, P < 0.0001) and DSS-induced colitis model (qRT-PCR, WB, IHC: P < 0.0001, P = 0.0045, P = 0.0004). Moreover, the expression of Zbtb7b was positively associated with the degree of UC activity. Mechanically, over-expression of Zbtb7b might activate the maturation of CD4⁺T cells (FCM, IF: P = 0.0240, P = 0.0003) and repress the differentiation of double-positive CD4⁺CD8⁺T (DP CD4⁺CD8⁺T) cells (FCM, IF: P = 0.0247, P = 0.0118), contributing to the production of inflammatory cytokines, such as TNF-α (P = 0.0005, P = 0.0005), IL-17 (P = 0.0014, P = 0.0381), and IFN-γ (P = 0.0016, P = 0.0042), in the serum and colonic tissue of DSS-induced colitis model.

CONCLUSIONS

Epigenetic DNA hypo-methylation of Zbtb7b activated the maturation of CD4⁺T cells and repressed the differentiation of DP CD4⁺CD8⁺ T cells, resulting in the production of inflammatory cytokines and colonic inflammation in UC. Therefore, Zbtb7b might be a diagnostic and therapeutic biomarker for UC, and hypo-methylation might affect the biological function of Zbtb7b.

Perindopril/Ambrosin Combination Mitigates Dextran Sulfate Sodium-Induced Colitis in Mice: Crosstalk between Toll-like Receptor 4, the Pro-Inflammatory Pathways, and SIRT1/PPAR-γ Signaling

Colitis is one of the inflammatory states that affect the intestinal wall and may even predispose to malignancy due to chronic irritation. Although the etiology of colitis is not yet fully explored, a combination of genetic and environmental factors is strongly incriminated. Perindopril is an angiotensin-converting enzyme inhibitor that is used for the management of a wide range of cardiovascular diseases. Ambrosin is a sesquiterpene lactone that was proven to have beneficial effects in disorders characterized by inflammatory nature. The objective of this study is to make a comparison between the effects of perindopril or ambrosin on dextran sulfate sodium (DSS)-induced colitis in mice and to explore the effect of their combination. The present findings indicate that each ambrosin or perindopril alone or in combination is able to ameliorate oxidative stress and suppress the proinflammatory pathways in the colonic tissues of DSS-treated mice via mechanisms related to toll-like receptor 4/nuclear factor kappa B signaling and modulation of peroxisome proliferator-activated receptor gamma/sirtuin-1 levels. In addition, each ambrosin or perindopril alone or in combination inhibits apoptosis and augments the mediators of autophagy in DSS-treated mice. These effects are reflected in the amelioration of the histopathological and electron microscopic changes in the colonic tissues. Interestingly, the most remarkable effects are those encountered with the perindopril/ambrosin combination compared to the groups treated with each of these agents alone. In conclusion, the perindopril/ambrosin combination might represent an effective modality for mitigation of the pathogenic events and the clinical sequelae of colitis.

IBD Subtype-Regulators IFNG and GBP5 Identified by Causal Inference Drive More Intense Innate Immunity and Inflammatory Responses in CD Than Those in UC

Background: The pathological differences between Crohn’s disease (CD) and ulcerative colitis (UC) are substantial and unexplained yet. Here, we aimed to identify potential regulators that drive different pathogenesis of CD and UC by causal inference analysis of transcriptome data.

Methods: Kruskal–Wallis and Dunnett’s tests were performed to identify differentially expressed genes (DEGs) among CD patients, UC patients, and controls. Subsequently, differentially expressed pathways (DEPs) between CD and UC were identified and used to construct the interaction network of DEPs. Causal inference was performed to identify IBD subtype-regulators. The expression of the subtype-regulators and their downstream genes was validated by qRT-PCR with an independent cohort.

Results: Compared with the control group, we identified 1,352 and 2,081 DEGs in CD and UC groups, respectively. Multiple DEPs between CD and UC were closely related to inflammation-related pathways, such as NOD-like receptor signaling, IL-17 signaling, and chemokine signaling pathways. Based on the priori interaction network of DEPs, causal inference analysis identified IFNG and GBP5 as IBD subtype-regulators. The results with the discovery cohort showed that the expression level of IFNG, GBP5, and NLRP3 was significantly higher in the CD group than that in the UC group. The regulation relationships among IFNG, GBP5, and NLRP3 were confirmed with transcriptome data from an independent cohort and validated by qRT-PCR.

Conclusion: Our study suggests that IFNG and GBP5 were IBD subtype-regulators that trigger more intense innate immunity and inflammatory responses in CD than those in UC. Our findings reveal pathomechanical differences between CD and UC that may contribute to personalized treatment for CD and UC.

Berberine inhibits IFN-γ signaling pathway in DSS-induced ulcerative colitis

Aims

The potential signaling pathways and core genes in ulcerative colitis (UC) were investigated in this study. Furthermore, potential mechanisms of BBR in treating UC were also explored.

Methods

Expression profiling by array of UC patients were obtained from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were determined with the differential analysis. The biological functions of DEGs were analyzed through the Database for Annotation, Visualization and Integrated Discovery (DAVID). The Gene Set Enrichment Analysis (GSEA) was applied to analyze the expression differences between two different phenotype sample sets. Dextran sulfate sodium (DSS) was applied to establish UC model of mice and lipopolysaccharide (LPS) was utilized to induce inflammatory damage of NCM460 cells. Therapeutic effects of berberine (BBR) on disease performance, pathologic changes and serum supernatant indices were analyzed in vivo. To further investigate the potential mechanisms of BBR in treating UC, the expression of genes and proteins in vivo and in vitro were examined by RT-qPCR, immunohistochemical staining and western blotting.

Results

Immune-inflammatory genes were identified and up-regulated significantly in UC patients. In addition, IFN-γ signaling pathway and its core genes were significantly up-regulated in the phenotype of UC. All disease performance and the pathologic changes of UC in mice were evidently ameliorated by BBR treatment. The pro-inflammatory cytokines of serum, including CXCL9, CXCL1, IL-17 and TNF-α, in UC mice were significantly reduced by treatment of BBR. In terms of mechanisms of BBR in treating UC, the pro-inflammatory and immune-related genes, encoding IFN-γ, IRF8, NF-κB and TNF-α decreased significantly in UC mice followed by BBR treatment. Meanwhile, the expression of IFN-γ and its initiated targets, including IRF8, Ifit1, Ifit3, IRF1, were suppressed significantly by BBR treatment in vivo. The blocking of IFN-γ in vitro led to the silence of IFN-γ signaling pathway after exposure to BBR. Furthermore, the blocking of IFN-γ in vitro led to the silence of IFN-γ signaling pathway after exposure to BBR.

Conclusion

BBR holds anti-inflammatory activity and can treat UC effectively. The anti-inflammatory property of BBR is tightly related to the suppression of IFN-γ signaling pathway, which is crucial in immune-inflammatory responses of the colon mucosa.

The Role of Innate and Adaptive Immune Cells in the Pathogenesis and Development of the Inflammatory Response in Ulcerative Colitis

Ulcerative colitis (UC) is a chronic inflammatory disease with an underlying excessive immune response directed against resident microbiota and/or dietary antigens. Both innate and adaptive immune cells play a crucial role in the pathogenesis of UC. In the case of innate immune response cells, neutrophils, dendritic cells, macrophages have a crucial impact on the development of the disease, as well as innate lymphoid cells, which have received a particular attention in recent years. On the other hand, mechanisms of the adaptive immune response involve cells such as: cytotoxic lymphocytes, regulatory lymphocytes Treg, or helper lymphocytes Th-Th2, Th9, Th17, Th22, among which significant discoveries about Th9 and Th17 lymphocytes have been made in recent years. Due to the presence of antibodies directed against resident microbiota or one's own tissues, the influence of B lymphocytes on the development of UC is also highlighted. Additionally, the impact of cytokines on shaping the immune response as well as sustaining inflammation seems to be crucial. This review briefly describes the current state of knowledge about the involvement of the innate and adaptive immune systems in the pathogenesis of UC. The review is based on personal selection of literature that were retrieved by a selective search in PubMed using the terms "ulcerative colitis" and "pathogenesis of ulcerative colitis". It included systematic reviews, meta-analyses and clinical trials. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents.

Integrative computational approach identifies immune-relevant biomarkers in ulcerative colitis

Ulcerative colitis is a common inflammatory bowel disease with a complex genetic and immune etiology. Immune infiltration plays a vital role in the development of ulcerative colitis. To explore potential biomarkers for ulcerative colitis and analyze characteristics of immune cell infiltration, we used bioinformatic analyses, including machine learning algorithms, cell type deconvolution methods, and pathway enrichment methods. In this study, we identified 216 differentially expressed mRNAs (DEMs), of which 153 were upregulated, and 63 were downregulated genes. DEMs were mainly enriched in infiltrating neutrophils and regulation of leukocyte migration. Moreover, eight candidate biomarkers, DPP10, MST1L, DPP10‐AS1, CEP55, ACSL1, MGP, OLFM4, and SGK1, were identified. Of these candidate biomarkers, MST1L, OLFM4, and DPP10 were then validated in the GSE48958 dataset and were predicted to be strongly correlated with infiltrating immune cells of ulcerative colitis. The underlying mechanism of these key genes in the development of colitis was also predicted by gene set variation analysis. To further validate these biomarkers' expression in ulcerative colitis, we determined mRNA levels of SGK1, CEP55, ACSL1, OLFM4, and DPP10 in lipopolysaccharides (LPS)‐stimulated Raw264.7 cells by quantitative reverse transcription‐polymerase chain reaction. We also examined SGK1, CEP55, ACSL1, OLFM4, DPP10, and MGP expression in the colon tissues of dextran sodium sulfate‐induced colitis mice. Consistent with the predicted computational results, the mRNA levels of these candidate genes were markedly changed in LPS‐stimulated Raw264.7 cells and inflamed colon tissues. Hence, our findings indicated that these critical genes may act as diagnostic biomarkers for ulcerative colitis and that differential immune infiltration cells may help illustrate the progression of ulcerative colitis.

The small RNA mascRNA differentially regulates TLR-induced proinflammatory and antiviral responses

MALAT1-associated small cytoplasmic RNA (mascRNA) is a highly conserved transfer RNA-like (tRNA-like) noncoding RNA whose function remains largely unknown. We show here that this small RNA molecule played a role in the stringent control of TLR-mediated innate immune responses. mascRNA inhibited activation of NF-κB and mitogen-activated protein kinase (MAPK) signaling and the production of inflammatory cytokines in macrophages stimulated with LPS, a TLR4 ligand. Furthermore, exogenous mascRNA alleviated LPS-induced lung inflammation. However, mascRNA potentiated the phosphorylation of IRF3 and STAT1 and the transcription of IFN-related genes in response to the TLR3 ligand poly(I:C) both in vitro and in vivo. Mechanistically, mascRNA was found to enhance K48-linked ubiquitination and proteasomal degradation of TRAF6, thereby negatively regulating TLR-mediated MyD88-dependent proinflammatory signaling while positively regulating TRIF-dependent IFN signaling. Additionally, heterogeneous nuclear ribonucleoprotein H (hnRNP H) and hnRNP F were found to interact with mascRNA, promote its degradation, and contribute to the fine-tuning of TLR-triggered immune responses. Taken together, our data identify a dual role of mascRNA in both negative and positive regulation of innate immune responses.

Cannabinoids and Endocannabinoid System Changes in Intestinal Inflammation and Colorectal Cancer

Despite the multiple preventive measures and treatment options, colorectal cancer holds a significant place in the world's disease and mortality rates. The development of novel therapy is in critical need, and based on recent experimental data, cannabinoids could become excellent candidates. This review covered known experimental studies regarding the effects of cannabinoids on intestinal inflammation and colorectal cancer. In our opinion, because colorectal cancer is a heterogeneous disease with different genomic landscapes, the choice of cannabinoids for tumor prevention and treatment depends on the type of the disease, its etiology, driver mutations, and the expression levels of cannabinoid receptors. In this review, we describe the molecular changes of the endocannabinoid system in the pathologies of the large intestine, focusing on inflammation and cancer.

A review of the biological and pharmacological activities of mesalazine or 5-aminosalicylic acid (5-ASA): an anti-ulcer and anti-oxidant drug

Mesalazine, also known as 5-aminosalicylic acid (5-ASA), is a synthetic drug from the family of nonsteroidal anti-inflammatory drugs (NSAIDs) used for inflammatory diseases of the gastrointestinal tract. However, 5-ASA has also been used for various other diseases due to its pharmacological effects, but they are usually scattered across various publications, which may limit further research and clinical use of this drug. This review is a summary of published information on the biological and pharmacological effects of 5-ASA with the aim of identifying its anti-oxidant role and medicinal use. 5-ASA data have been collected from 1987 to February 2021 using major databases such as Web of Science, PubMed, Elsevier, Wiley Online Library, Springer, Google Scholar, etc. According to research, the pharmacological and biological effects of 5-ASA include treatment of inflammatory bowel disease, and anti-oxidant, anti-inflammatory, antibacterial, antifungal, anticancer, anti-amyloid, gastric protection (gastroprotective), and antidiverticulosis properties. Numerous pharmacological studies have shown that 5-ASA is an anti-oxidant and anti-ulcer compound with high therapeutic potential that, if the appropriate dose is discovered, its chemical structure changes and its effectiveness is optimized, 5-ASA has been used experimentally for other diseases.

Drug Targeting of Inflammatory Bowel Diseases by Biomolecules

Inflammatory bowel disease (IBD) is a group of disabling, destructive and incurable immune-mediated inflammatory diseases comprising Crohn’s disease (CD) and ulcerative colitis (UC), disorders that are highly prevalent worldwide and demand a large investment in healthcare. A persistent inflammatory state enables the dysfunction and destruction of healthy tissue, hindering the initiation and endurance of wound healing. Current treatments are ineffective at counteracting disease progression. Further, increased risk of serious side effects, other comorbidities and/or opportunistic infections highlight the need for effective treatment options. Gut microbiota, the key to preserving a healthy state, may, alternatively, increase a patient’s susceptibility to IBD onset and development given a relevant bacterial dysbiosis. Hence, the main goal of this review is to showcase the main conventional and emerging therapies for IBD, including microbiota-inspired untargeted and targeted approaches (such as phage therapy) to infection control. Special recognition is given to existing targeted strategies with biologics (via monoclonal antibodies, small molecules and nucleic acids) and stimuli-responsive (pH-, enzyme- and reactive oxygen species-triggered release), polymer-based nanomedicine that is specifically directed towards the regulation of inflammation overload (with some nanosystems additionally functionalized with carbohydrates or peptides directed towards M1-macrophages). The overall goal is to restore gut balance and decrease IBD’s societal impact.

Identification of the Molecular Basis of Nanocurcumin-Induced Telocyte Preservation within the Colon of Ulcerative Colitis Rat Model

Background

Telocytes (TCs) are a distinct type of interstitial cells that play a vital role in the pathogenesis of ulcerative colitis and colonic tissue hemostasis. The aim of this study was to examine the effect of nanocurcumin (NC) on the morphometric and immunohistochemical characterization of TCs in the ulcerative colitis (UC) rat model.

Methods

Forty rats were randomly divided into control, NC, UC, and UC+NC groups. At the end of the experiment, the colon was dissected and prepared for histopathological and immunohistochemical assessment. Tissue homogenates were prepared for real-time PCR assessment of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta (TGF-β) gene expression. Our results revealed extensive mucosal damage with inflammatory cell infiltration, significant reduction of CD34, and vimentin immunostained TCs in the colon of the UC group with significant elevation of expression of IL-6, TNF-α, and TGF-β. The UC+NC-treated group revealed significant elevation of TC count compared to the UC group besides, a significant reduction of the three gene expression.

Conclusion

NC successfully targeted the colonic tissue, improved the mucosal lesion, preserve TCs distribution, and count through its anti-inflammatory and fibrinolytic properties.