What Does Disease Progression Look Like in Ulcerative Colitis, and How Might It Be Prevented?

HSP90β shapes the fate of Th17 cells with the help of glycolysis-controlled methylation modification

BACKGROUND AND PURPOSE

Ulcerative colitis (UC) is a refractory inflammatory disease associated with immune dysregulation. Elevated levels of heat shock protein (HSP) 90 in the β but not α subtype were positively associated with disease status in UC patients. This study validated the possibility that pharmacological inhibition or reduction of HSP90β would alleviate colitis, induced by dextran sulfate sodium, in mice and elucidated its mechanisms.

EXPERIMENTAL APPROACH

Histopathological and biochemical analysis assessed disease severity, and bioinformatics and correlation analysis explained the association between the many immune cells and HSP90β. Flow cytometry was used to analyse the homeostasis and transdifferentiation of Th17 and Treg cells. In vitro inhibition and adoptive transfer assays were used to investigate functions of the phenotypically transformed Th17 cells. Metabolomic analysis, DNA methylation detection and chromatin immunoprecipitation were used to explore these mechanisms.

KEY RESULTS

The selective pharmacological inhibitor (HSP90βi) and shHSP90β significantly mitigated UC in mice and promoted transformation of Th17 to Treg cell phenotype, via Foxp3 transcription. The phenotypically-transformed Th17 cells by HSP90βi or shHSP90β were able to inhibit lymphocyte proliferation and colitis in mice. HSP90βi and shHSP90β selectively weakened glycolysis by stopping the direct association of HSP90β and GLUT1, the key glucose transporter, to accelerate ubiquitination degradation of GLUT1, and enhance the methylation of Foxp3 CNS2 region. Then, the mediator path was identified as the "lactate-STAT5-TET2" cascade.

CONCLUSION AND IMPLICATIONS

HSP90β shapes the fate of Th17 cells via glycolysis-controlled methylation modification to affect UC progression, which provides a new therapeutic target for UC.

Downregulation of OATP2B1 by proinflammatory cytokines leads to 5-ASA hyposensitivity in Ulcerative colitis

5-Aminosalicylic acid (5-ASA) is a first-line agent in both remission and maintenance therapy for ulcerative colitis (UC). However, the mucosal concentration of 5-ASA was significantly lower in patients with severe histological inflammation, which further led to a poor response to 5-ASA treatment. Our study aimed to clarify the mechanism of 5-ASA uptake into colonic epithelial cells and to further explore the reason for the decreased colonic mucosal 5-ASA concentration in UC patients. Our results demonstrated that the colonic 5-ASA concentration was notably reduced in DSS-induced colitis mice and inversely correlated with colonic inflammation. 5-ASA was not a substrate of carnitine/organic cation transporter 1/2 (OCTN1/2) or multidrug resistance protein 1 (MDR1), whereas organic anion transporting polypeptide 2B1 (OATP2B1) and sodium-coupled monocarboxylate transporter 1 (SMCT1) mediated the uptake of 5-ASA, with a greater contribution from OATP2B1 than SMCT1. Inhibitors and siRNAs targeting OATP2B1 significantly reduced 5-ASA absorption in colonic cell lines. Moreover, OATP2B1 expression was dramatically downregulated in colon tissues from UC patients and dextran sodium sulfate (DSS)-induced colitis mice, and was also negatively correlated with colonic inflammation. Mechanistically, mixed proinflammatory cytokines downregulated the expression of OATP2B1 in a time- and concentration-dependent manner through the hepatocyte nuclear factor 4 α (HNF4α) pathway. In conclusion, OATP2B1 was the pivotal transporter involved in colonic 5-ASA uptake, which indicated that inducing OATP2B1 expression may be a strategy to promote 5-ASA uptake and further improve the concentration and anti-inflammatory efficacy of 5-ASA in UC.

Disease Clearance as a New Outcome in Ulcerative Colitis: a Systematic Review and Expert Consensus

The concept of disease clearance has been proposed as a potential target in ulcerative colitis (UC). We conducted a systematic review to investigate the role of disease clearance, defined as a composite outcome including simultaneous clinical, endoscopic, and histologic remission of disease in the management of patients with UC. Based on the literature data, statements regarding disease clearance were developed and voted on by the members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) according to a Delphi methodology. A definition of disease clearance was proposed to standardize its use in clinical practice and clinical trials and to provide practical recommendations for its implementation as a therapeutic target in UC.

Biochanin a ameliorates DSS-induced ulcerative colitis by improving colonic barrier function and protects against the development of spontaneous colitis in the Muc2 deficient mice

There is an increasing appreciation that colonic barrier function is closely related to the development and progression of colitis. The mucus layer is a crucial component of the colonic barrier, responsible for preventing harmful bacteria from invading the intestinal epithelium and causing inflammation. Furthermore, a defective mucus barrier is also a significant characteristic of ulcerative colitis (UC). Biochanin A (BCA), an isoflavonoid, has garnered increasing interest due to its significant biological activities. However, the impact of BCA on UC has not been reported yet. In this study, we used a dextran sodium sulfate (DSS)-induced ulcerative colitis model and the Muc2 deficient (Muc2-/-) mice spontaneous colitis model to explore the mechanisms of BCA in the treatment of UC. Here, we verified that DSS-induced UC was observably attenuated and spontaneous colitis in Muc2-/- mice was relieved by BCA. Treatment with BCA improved colitis-related symptoms and reduced intestinal permeability by upregulating the levels of goblet cells and tight junction (TJ) proteins. In addition, we confirmed that BCA promotes autophagy through the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) pathway, thereby alleviating DSS-induced UC. In addition, the administration of BCA was able to reduce apoptosis and promote proliferation by suppressing Cleaved Caspase-3 (Cleaved Cas-3) expression, and increasing PCNA and Ki67 levels. Further research revealed that BCA treatment ameliorated spontaneous colitis and alleviated epithelial damage in Muc2-/- mice by restoring the intestinal barrier and promoting autophagy. Our results demonstrated that BCA alleviated UC by enhancing intestinal barrier function and promoting autophagy. These findings indicate that BCA may be a novel treatment alternative for UC.

Challenges in IBD Research 2024: Precision Medicine

Precision medicine is part of 5 focus areas of the Challenges in IBD Research 2024 research document, which also includes preclinical human IBD mechanisms, environmental triggers, novel technologies, and pragmatic clinical research. Building on Challenges in IBD Research 2019, the current Challenges aims to provide a comprehensive overview of current gaps in inflammatory bowel diseases (IBDs) research and deliver actionable approaches to address them with a focus on how these gaps can lead to advancements in interception, remission, and restoration for these diseases. The document is the result of multidisciplinary input from scientists, clinicians, patients, and funders, and represents a valuable resource for patient-centric research prioritization. In particular, the precision medicine section is focused on the main research gaps in elucidating how to bring the best care to the individual patient in IBD. Research gaps were identified in biomarker discovery and validation for predicting disease progression and choosing the most appropriate treatment for each patient. Other gaps were identified in making the best use of existing patient biosamples and clinical data, developing new technologies to analyze large datasets, and overcoming regulatory and payer hurdles to enable clinical use of biomarkers. To address these gaps, the Workgroup suggests focusing on thoroughly validating existing candidate biomarkers, using best-in-class data generation and analysis tools, and establishing cross-disciplinary teams to tackle regulatory hurdles as early as possible. Altogether, the precision medicine group recognizes the importance of bringing basic scientific biomarker discovery and translating it into the clinic to help improve the lives of IBD patients.

Peripheral helper T cells in human diseases

Peripheral helper T cells (Tph) are a specialized subset of CD4+ T cells with the ability to help B cells and induce antibody production. Although usually located in ectopic lymphoid-like structures (ELS), inside the peripheral blood, Tph cells can also be identified. The aberrant proliferation and functions of Tph cells are commonly found in the patients with disease. In this review, first we will summarize the biological characteristics of Tph cells, such as the expression of surface molecules, transcription factors and cytokines, and discuss its B cell help functions. Tph cells also have roles in a wide range of human diseases, including autoimmune diseases, infectious diseases, malignancies etc. Therefore, there is a strong interest in targeting Tph cells to improve treat strategies of human diseases.

Drug Optimization in Patients with Mild-to-Moderate Ulcerative Colitis: A Global Survey

Background/Objectives: The treatment of patients with mild-to-moderate ulcerative colitis (UC) is challenging. Although there are commonly used guidelines, therapy optimization is not standardized. We conducted a survey to investigate the management and treatment of patients with mild-to-moderate UC. Methods: Physicians with experience in treating inflammatory bowel diseases (IBD) were invited to participate in an anonymous, multiple-choice survey between June and July 2023. The survey addressed various issues of patient care such as patient monitoring, treatment optimization, follow-up, treatment decision making, and therapy de-escalation. Results: The survey included 222 physicians (59.9% men; mean age = 50.4 years) from 66 countries worldwide. Gastroenterologists were the most represented specialists (89.6%), followed by surgeons (3.2%), and internal medicine doctors (2.7%). Two-thirds of the participants (66.7%) had >10 years of experience in the field of IBD. The combination of oral (≥4 g/day) and rectal 5-aminosalicylic acid (5-ASA) was the preferred choice when optimizing therapy. Budesonide MMX (41.8%) and systemic steroids (39.9%) were preferred in patients who failed 5-ASA. Treatment decisions were predominantly based on endoscopic (99.0%) or clinical (59.8%) activity. A significant percentage of clinicians did not optimize therapy in the case of increased fecal calprotectin alone (45.1%) or radiological/ultrasound activity (39.8%) alone. Conclusions: The guidelines for the management of mild-to-moderate UC are well accepted in clinical practice. Endoscopic remission remains the main therapeutic target, followed by clinical remission. Fecal calprotectin and intestinal ultrasound still elicit complaints from physicians.

Disease clearance in ulcerative colitis: A new therapeutic target for the future

Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression. This has fueled the identification of molecular targets, resulting in a rapidly expanding therapeutic armamentarium. Subsequently, management strategies have evolved from symptomatic resolution to well-defined objective endpoints, including clinical remission, endoscopic remission and mucosal healing. While the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications, studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic measures. Current recommendations lack consideration of histological healing. The simultaneous achievement of clinical, endoscopic, and histologic remission has not been fully investigated. This has laid the groundwork for a novel therapeutic outcome termed disease clearance (DC). This article summarizes the concept of DC and its current evidence.

Effectiveness and safety of vedolizumab and infliximab in biologic-naïve patients with moderate-to-severe ulcerative colitis: A multicenter, retrospective cohort study

OBJECTIVES

We conducted this multicenter, retrospective cohort study aiming to evaluate the effectiveness and safety of vedolizumab (VDZ) and infliximab (IFX) in biologic-naïve patients with moderate-to-severe ulcerative colitis (UC).

METHODS

Biologic-naïve patients with moderate-to-severe UC who were treated with IFX or VDZ for at least 14 weeks at three tertiary hospitals in southwest China between January 2021 and January 2023 were retrospectively included. Efficacy of the biologics was evaluated based on the steroid-free clinical remission rate, clinical remission rate, and mucosal healing rate at Weeks 14 and 52. Adverse events related to biologic use were recorded.

RESULTS

Altogether 122 biologic-naïve patients with moderate-to-severe UC were included. No marked differences in the steroid-free clinical remission rate and clinical remission rate were observed between the two groups at Week 14 or Week 52 (P > 0.05). The VDZ group exhibited a higher mucosal healing rate at Week 14 compared to the IFX group (33.3% vs 16.9%, P = 0.036), while that at Week 52 did not differ between the two groups (65.6% vs 47.1%, P = 0.098). There was no statistically significant difference in the rate of adverse events between the two groups (P = 0.071).

CONCLUSION

VDZ and IFX showed comparable clinical efficacy and safety profiles and can be used as viable first-line therapeutic options for biologic-naïve patients with moderate-to-severe UC.

Targeting inflammation as cancer therapy

Inflammation has accompanied human beings since the emergence of wounds and infections. In the past decades, numerous efforts have been undertaken to explore the potential role of inflammation in cancer, from tumor development, invasion, and metastasis to the resistance of tumors to treatment. Inflammation-targeted agents not only demonstrate the potential to suppress cancer development, but also to improve the efficacy of other therapeutic modalities. In this review, we describe the highly dynamic and complex inflammatory tumor microenvironment, with discussion on key inflammation mediators in cancer including inflammatory cells, inflammatory cytokines, and their downstream intracellular pathways. In addition, we especially address the role of inflammation in cancer development and highlight the action mechanisms of inflammation-targeted therapies in antitumor response. Finally, we summarize the results from both preclinical and clinical studies up to date to illustrate the translation potential of inflammation-targeted therapies.

Protective effect of FKBP12 on dextran sulfate sodium-induced ulcerative colitis in mice as a tacrolimus receptor

Ulcerative colitis (UC) is a multifactorial intestinal disease with a high incidence. In recent years, there has been an urgent need for pleiotropic drugs with a clear biosafety profile. Tacrolimus (TAC) is an immunosuppressant with stronger in vivo effects and better gastrointestinal absorption and is considered a potential treatment for UC. FKBP12 is a mediator of TAC immunosuppression; however, it is unclear whether it can participate in the development of UC in combination with TAC. The purpose of this study is to preliminarily validate the function of FKBP12 by establishing dextran sulfate sodium (DSS)-induced UC model and TAC treatment. The results revealed that TAC was effective in alleviating DSS-induced UC symptoms such as body weight and disease activity index (DAI). TAC significantly protects colonic tissue and attenuates DSS-induced histomorphological changes. In addition, FKBP12 is down-regulated in the intestinal tissue of DSS-induced UC mice and in serum samples of UC patients. In conclusion, our study revealed that FKBP12 may act as a TAC receptor to have anti-inflammatory and protective effects on DSS-induced UC in mice, which will provide a new option for the treatment of UC.

Lactate Protects Intestinal Epithelial Barrier Function from Dextran Sulfate Sodium-Induced Damage by GPR81 Signaling

The dysregulation of the intestinal epithelial barrier significantly contributes to the inflammatory progression of ulcerative colitis. Recent studies have indicated that lactate, produced by gut bacteria or derived from fermented foods, plays a key role in modulating inflammation via G-protein-coupled receptor 81 (GPR81). In this study, we aimed to investigate the potential role of GPR81 in the progression of colitis and to assess the impact of lactate/GPR81 signaling on intestinal epithelial barrier function. Our findings demonstrated a downregulation of GPR81 protein expression in patients with colitis. Functional verification experiments showed that Gpr81-deficient mice exhibited more severe damage to the intestinal epithelial barrier and increased susceptibility to DSS-induced colitis, characterized by exacerbated oxidative stress, elevated inflammatory cytokine secretion, and impaired expression of tight-junction proteins. Mechanistically, we found that lactate could suppress TNF-α-induced MMP-9 expression and prevent the disruption of tight-junction proteins by inhibiting NF-κB activation through GPR81 in vitro. Furthermore, our study showed that dietary lactate could preserve intestinal epithelial barrier function against DSS-induced damage in a GPR81-dependent manner in vivo. Collectively, these results underscore the crucial involvement of the lactate/GPR81 signaling pathway in maintaining intestinal epithelial barrier function, providing a potential therapeutic strategy for ulcerative colitis.

Clinical Application of Intestinal Ultrasound in Inflammatory Bowel Disease

PURPOSE OF REVIEW

Intestinal ultrasound (IUS) is a non-invasive, accurate, and well-tolerated tool that provides real-time assessment of inflammatory bowel disease (IBD) activity and is therefore an ideal monitoring tool. This review describes the evolving role of IUS in each phase of clinical management of IBD.

RECENT FINDINGS

Accumulating evidence has demonstrated that IUS is an excellent tool for the assessment of suspected IBD, with a very high negative predictive value. It accurately assesses disease activity, disease complications, and in the pre-treatment phase, provides a benchmark for subsequent follow-up. IUS can detect early therapeutic response and correlates well with other established monitoring modalities with arguably superior predictive capabilities and ability to assess a deeper degree of remission, transmural healing (TH). IUS has a crucial role in the management of IBD and has ushered in a new era of monitoring with more rapid evaluation and the opportunity for early optimization, deeper therapeutic targets, and improved outcomes.

α-Lipoic acid alleviates dextran sulfate sodium salt-induced ulcerative colitis via modulating the Keap1-Nrf2 signaling pathway and inhibiting ferroptosis

BACKGROUND

Inflammatory bowel disease (IBD) is a chronically relapsing inflammatory disease with severe diarrhea, fatigue and weight loss. α-Lipoic acid (LA), a well-known antioxidant, is able to scavenge reactive oxygen species (ROS) and maintain a healthy cellular redox state. However, the role of LA in protecting IBD is still unclear. Hence the aim of this research was to investigate the protective effect of LA on dextran sulfate sodium salt-induced ulcerative colitis (UC) and its underlying mechanism.

RESULTS

Here, our findings showed that LA significantly alleviated UC symptoms and the overproduction of pro-inflammatory cytokines in UC mice. In addition, LA treatment inhibited intestinal cell apoptosis by regulating the expression levels of p53/caspase-3 pathway-related protein in UC mice. Meanwhile, the inhibitory effects of LA on colonic oxidative stress and ferroptosis were revealed. Our study further demonstrated that LA treatment could regulate the Kelch-like ECH-associating protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway. Interestingly, we confirmed that LA inhibited ferroptosis by attenuating endoplasmic reticulum stress and suppressing apoptosis in erastin-induced ferroptosis model in vitro.

CONCLUSION

Taken together, this study's findings suggest that LA could be considered as a therapeutic agent protecting against IBD. © 2023 Society of Chemical Industry.

Investigation of Tongxie-Yaofang formula in treating ulcerative colitis based on network pharmacology via regulating MAPK/AKT signaling pathway

BACKGROUND

Ulcerative colitis (UC) is a subtype of inflammatory bowel disease, which often leads to bloody diarrhea and abdominal pain. In this study, the function mechanism of Tongxie-Yaofang formula (TXYF) on UC was investigated.

METHODS

Action targets of TXYF were obtained by Traditional Chinese Medicine Systems Pharmacology Database (TCMSP) and Traditional Chinese Medicine Integrated Database (TCMID) databases. The targets of UC were screened in Gene Cards and Online Mendelian Inheritance in Man (OMIM) databases. The network pharmacology of active ingredient targets was established via Cytoscape.

RESULTS

A total of 42 chemical components and 5806 disease targets were obtained. The GO functional analysis showed that biological processes such as oxidative stress and molecular response to bacteria, molecular function such as protein and nucleic acid binding activity were significantly enriched. The top 20 KEGG enriched signal pathways indicated that the targets were mainly linked with IL-17, TNF, HIF-1. Molecular docking results showed that naringenin had good binding activity between naringin and MAPK, albiflorin and SRC. The activity of MPO, the concentration of HIF-1, IL-17 and TNF-α were significantly decreased after TXYF treatment. The characteristics of UC such as crypt distortion, crypt atrophy, and increased basal plasmacytosis were also less observed with the treatment of TXYF. What's more, TXYF suppresses the phosphorylation of SRC, MAPK and AKT1 in UC.

CONCLUSIONS

TXYF showed treatment effect on UC through multiple components and multiple targets, which lays a foundation for further study of UC treatment.

Histological healing as a predictor of sustained clinical remission in paediatric ulcerative colitis

BACKGROUND

The study aimed to assess the longitudinal impact of endoscopic healing (EH) and histological healing (HH) in a cohort of paediatric patients affected by ulcerative colitis (UC).

METHODS

This was a retrospective single-centre longitudinal study. 86 children with UC who underwent endoscopic re-assessment while in clinical and biochemical remission were included. Partial EH was defined as a Mayo Endoscopic Subscore (MES) of 1 and complete EH was defined as a MES of 0. HH was defined as the absence of active inflammation in all biopsies. The cumulative incidence of clinical relapse was evaluated during follow-up.

RESULTS

At the second endoscopic re-evaluation, 59 (68.6%) patients achieved EH (MES ≤1). Of these patients, 39 (66%) achieved complete EH. 20 of the 39 patients who achieved complete EH attained complete HH. Patients who achieved partial and complete EH showed higher recurrence-free survival rates compared to those who did not (p < 0.01 and p < 0.01, respectively). Amongst patients with complete EH, those who achieved complete HH had lower recurrence rates when compared to patients who still showed microscopic inflammation (p = 0.049).

CONCLUSION

Achievement of EH and HH is associated with fewer disease relapses, with patients achieving HH showing longer relapse-free survival rates.

Exploring the causal relationship between inflammatory bowel disease and sarcopenia-related traits: a two-sample Mendelian randomization analysis

Previous observational studies have shown an association between inflammatory bowel disease (IBD) and sarcopenia. However, the causal relationship between IBD (including ulcerative colitis and Crohn's disease) and sarcopenia remains unclear. Thus, this study investigated whether genetically predicted IBD play a function in the occurrence of sarcopenia using Mendelian randomization (MR) analysis. This study used independent single nucleotide polymorphisms (SNPs) significantly associated with IBD as instrument variables (IVs). Sarcopenia-related components (hand grip strength, walking space, and appendicular lean mass (ALM)) were investigated as outcome factors, with summary-level data regarding these components of sarcopenia obtained from the UK Biobank. The IVW-MR analysis revealed that there were significant negative associations between IBD and hand grip strength (both left and right) as well as ALM. Besides, the results of IVW-MR analysis provided strong evidence of a causal relationship between genetically predicted Crohn's disease and hand grip strength and ALM. However, there were no significant associations found between ulcerative colitis and sarcopenia-related traits. Sensitivity tests confirmed the accuracy and robustness of the above MR analysis. Conclusions: Our MR analysis showed the causal effect of Crohn's disease on hand grip strength and ALM. This suggests that Crohn's disease may be a potential risk factor for sarcopenia.

The Epidemiology of Inflammatory Bowel Disease in Oceania: A Systematic Review and Meta-Analysis of Incidence and Prevalence

BACKGROUND

Past studies have shown high rates of inflammatory bowel disease (IBD) in Australia and New Zealand (NZ). We aimed to describe the epidemiology of IBD in Australia, NZ, and the surrounding region (collectively termed Oceania) by conducting a systematic review and meta-analysis.

METHODS

Electronic databases were searched from inception to April 2023 for studies reporting incidence or prevalence rates of IBD, Crohn's disease (CD), or ulcerative colitis (UC) in Oceania. All study designs were included. A meta-analysis calculated pooled estimates of incidence and prevalence, and a sensitivity analysis compared the pooled population-based studies with the non-population-based studies and the Australian and NZ studies separately.

RESULTS

Nineteen incidence and 11 prevalence studies were included; 2 studies were from the Pacific Islands, with the rest coming from Australia and NZ. Pooled estimates showed high incidence rates of 19.8 (95% confidence interval [CI], 15.8-23.7) for IBD, 8.3 (95% CI, 6.9-9.8) for CD, and 7.4 (95% CI, 5.7-9.1) for CD per 100 000 person-years. CD was more common than UC in most studies. The pooled estimates for the prevalence studies were 303.3 (95% CI, 128.1-478.4) for IBD, 149.8 (95% CI, 71.0-228.5) for CD, and 142.2 (95% CI, 63.1-221.4) for UC per 100 000 persons. Studies using population-based data collection methods showed higher pooled rates for both incidence and prevalence.

CONCLUSIONS

The incidence and prevalence of IBD in Oceania is high. The studies were heterogeneous and there were several geographic areas with no information, highlighting the need for more epidemiological studies of IBD.

Ginsenoside Rg1 Alleviates Ulcerative Colitis in Obese Mice by Regulating the Gut Microbiota-Lipid Metabolism-Th1/Th2/Th17 Cells Axis

Ginsenoside Rg1 (G-Rg1) has various pharmacological properties including antiobesity, immunomodulatory, and anti-inflammatory effects. This study aimed to explore the therapeutic effects and underlying mechanisms of G-Rg1 on colitis complicated by obesity. The results indicate that G-Rg1 effectively alleviates colitis in obese mice and improves serum lipid levels and liver function. Importantly, G-Rg1 improved the composition of gut microbiota in obese mice with colitis, with increases in alpha diversity indexes Sobs, Ace, and Chao, a significant down-regulation of the relative abundance of Romboutsia, and a significant up-regulation of Rikenellaceae_RC9_gut_group, Lachnospiraceae_NK4A136_group, Enterorhabdus, Desulfovibrio, and Alistipes. Meanwhile, G-Rg1 improved lipid metabolism in the colonic contents of obese mice with colitis. Additionally, G-Rg1 significantly reduced the percentages of helper T (Th)1, Th17, central memory T (TCM), and effector memory T (TEM) cells in obese mice with colitis while significantly increasing Naïve T and Th2 cells. In conclusion, G-Rg1 could be a promising therapeutic option for alleviating obesity complicated by colitis through regulation of the gut microbiota and lipid metabolism as well as Th1/Th2/Th17 cell differentiation.

Citropten alleviates acute and recurrent colitis via blockage of NF-κB and JAK/STAT3 pathways

Inflammatory bowel disease (IBD) is a chronic inflammatory bowel disease, which is characterized by inflammation, with many symptoms including diarrhea, abdominal pain, bloody stool, and weight loss. It is difficult to completely cure and promising therapeutic drug candidates are urgently needed. Citropten, a coumarin-like compound found in traditional Chinese medicine such as Finger Citron Fruit, notopterygium root and citrus peel, has been shown to inhibit the proliferation of tumor cells, protect against depression and suppress the production of inflammatory mediators. In this study, we demonstrated that citropten could alleviate dextran sulfate sodium (DSS)-induced acute and recurrent colitis in mice, with significant improvement in body weight loss, disease activity index, shortened colon length and histological changes. Moreover, citropten dramatically decreased the production of pro-inflammatory mediators in colon tissues and effectively suppressed the proportion of Th17 cells in spleen. Mechanism investigations revealed that citropten significantly inhibited the activation of NF-κB and JAK/STAT3 signaling pathways, thus leading to decreased inflammation, Th17 cells and alleviative colitis. These findings provide novel insights into the anti-colitis effect of citropten, which may be a promising drug candidate for treatment of IBD.

Understanding the molecular mechanisms of anti-trafficking therapies and their clinical relevance in inflammatory bowel disease

In patients with inflammatory bowel disease (IBD), a combination of dysbiosis, increased intestinal permeability, and insufficient regulatory responses facilitate the development of chronic inflammation, which is driven by a complex interplay between the mucosal immune system and the environment and sustained by immune priming and ongoing cellular recruitment to the gut. The localization of immune cells is mediated by their expression of chemokine receptors and integrins, which bind to chemokines and adhesion molecules, respectively. In this article, we review the mechanisms of action of anti-trafficking therapies for IBD and consider clinical observations in the context of the different mechanisms of action. Furthermore, we discuss the evolution of molecular resistance to anti-cytokines, in which the composition of immune cells in the gut changes in response to treatment, and the potential implications of this for treatment sequencing. Lastly, we discuss the relevance of mechanism of action to combination therapy for IBD.

Mitochondrial DNA copy number is associated with Crohn's disease: a comprehensive Mendelian randomization analysis

Mitochondrial DNA plays a critical role in the pathophysiological process of inflammation. However, the relationship between mitochondrial DNA copy number (mtDNA-CN) and inflammatory bowel diseases (IBD) remains poorly understood. We conducted a comprehensive Mendelian randomization (MR) using three instrumental variables (IVs) to explore the causal associations between mtDNA-CN and IBD, including Crohn's disease (CD), ulcerative colitis (UC). MR-Egger regression, weighted median, inverse-variance weighted (IVW), and weighted mode methods were used to evaluate the potential causal associations. The robustness of the IVW estimates was determined using the leave-one-out sensitivity test. A meta-analysis was conducted to pool the results from the three sets of IVs. Upon analysis, the findings of the current study revealed that genetically predicted mtDNA-CN was not associated with IBD (CD + UC) and UC. The results of MR analyses between mtDNA-CN and CD risk were inconsistent by using three sets of IVs. After a meta-analysis, we found that genetically predicted mtDNA-CN was associated with CD risk (odds ratio = 2.09; 95% confidence interval: 1.37-3.18). This finding was also confirmed by multivariable MR analyses and remained robust when tested with the leave-one-out sensitivity test. In conclusion, genetically predicted mtDNA-CN was found to be associated with CD risk. Therefore, mtDNA levels in the blood could potentially be used as a marker for CD risk assessment. Further studies are needed to elucidate the underlying mechanisms and validate the results of this study.

Oral Administration of Platinum Nanoparticles with SOD/CAT Cascade Catalytic Activity to Alleviate Ulcerative Colitis

Ulcerative colitis (UC) is a refractory chronic inflammatory disease involving the colon and rectum, falling under the category of inflammatory bowel disease (IBD). The accumulation of reactive oxygen species (ROS) in local tissues has been identified as a crucial contributor to the escalation of inflammatory responses. Therefore, eliminating ROS in the inflamed colon is a promising approach to treating UC. Nanomaterials with intrinsic enzyme-like activities (nanozymes) have shown significant therapeutic potential in UC. In this study, we found that platinum nanoparticles (Pt NPs) exhibited remarkable superoxide dismutase (SOD) and catalase (CAT) cascade catalytic activities, as well as effective hydroxyl radical (•OH) scavenging ability. The in vitro experiments showed that Pt NPs could eliminate excessive ROS to protect cells against oxidative stress. In the colitis model, oral administration of Pt NPs (loaded in chitosan/alginate hydrogel) could significantly alleviate UC, including reducing the colon length, the damaged epithelium, and the infiltration of inflammatory cells. Without appreciable systemic toxicity, Pt NPs represent a novel therapeutic approach to UC and are expected to achieve long-term inflammatory remission.

Bowel Urgency in Ulcerative Colitis: Current Perspectives and Future Directions

Bowel urgency (BU), the sudden or immediate need for a bowel movement, is one of the most common and disruptive symptoms experienced by patients with ulcerative colitis (UC). Distinct from the separate symptom of increased stool frequency, BU has a substantial negative impact on quality of life and psychosocial functioning. Among patients with UC, BU is one of the top reasons for treatment dissatisfaction and one of the symptoms patients most want improved. Patients may not discuss BU often due to embarrassment, and healthcare providers may not address the symptom adequately due to the lack of awareness of validated tools and/or knowledge of the importance of assessing BU. The mechanism of BU in UC is multifactorial and includes inflammatory changes in the rectum that may be linked to hypersensitivity and reduced compliance of the rectum. Responsive and reliable patient-reported outcome measures of BU are needed to provide evidence of treatment benefits in clinical trials and facilitate communication in clinical practice. This review discusses the pathophysiology and clinical importance of BU in UC and its impact on the quality of life and psychosocial functioning. Patient-reported outcome measures developed to assess the severity of BU in UC are discussed alongside overviews of treatment options and clinical guidelines. Implications for the future management of UC from the perspective of BU are also explored.

Forsythia suspensa (Thunb.) Vahl extract ameliorates ulcerative colitis via inhibiting NLRP3 inflammasome activation through the TLR4/MyD88/NF-κB pathway

BACKGROUND

Ulcerative colitis (UC), a chronic inflammatory disease, is caused by abnormal immune system reactions resulting in inflammation and ulcers in the large intestine. Phillygenin (PHI) is a natural compound found in Forsythia suspensa (Thunb.) Vahl, which is known for its antipyretic, anti-inflammatory, antiobesity, and other biological activities. However, the therapeutic role and molecular mechanisms of PHI on UC are still insufficiently researched.

METHODS

In this study, dextran sulfate sodium (DSS) and 2.5% 2,4,6-trinitro-Benzenesulfonic acid (TNBS)-induced acute UC were used to investigate the therapeutic effects of PHI. We evaluated the effects of PHI on disease activity index (DAI), body weight, mortality, intestinal mucosal barrier, cytokine secretion, and macrophage infiltration into colon tissue using various techniques such as flow cytometry, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), RT-qPCR, and Western blot analysis.

RESULTS

Our findings revealed that PHI has therapeutic properties in UC treatment. PHI was able to maintain body weight, reduce DAI and mortality, restore the intestinal mucosal barrier, and inhibit cytokine secretion. Flow cytometry assay and immunofluorescence indicated that PHI reduces macrophage infiltration into colon tissue. Mechanistically, PHI may exert anti-inflammatory effects by downregulating the TLR4/MyD88/NF-κB pathway and inhibiting the activation of NLRP3 inflammasome.

CONCLUSION

In conclusion, PHI possesses significant anti-inflammatory properties and is expected to be a potential drug for UC treatment. Our study delves into the underlying mechanisms of PHI therapy and highlights the potential for further research in developing PHI-based treatments for UC.

Point-of-Care Intestinal Ultrasound in Pediatric Inflammatory Bowel Disease

PURPOSE OF REVIEW

Intestinal ultrasound (IUS) is an emerging non-invasive point-of-care tool utilized by pediatric gastroenterologists for accurately detecting and monitoring inflammatory bowel disease (IBD) activity. In this article, we reviewed the evidence supporting and technique to perform IUS for children with IBD.

RECENT FINDINGS

IUS technique can visualize the colon from the distal sigmoid until the cecum and the terminal ileum without the need for bowel preparation, fasting, or sedation in children with IBD. IUS has been shown to be accurate to endoscopy in children with ulcerative colitis and Crohn's disease. IUS may be the most accurate biomarker to follow as a marker of treatment response that is predictive of endoscopic outcomes in children with IBD. Multiple studies have demonstrated that IUS can be performed at the point-of-care for IBD activity assessment in children. Recent studies have demonstrated the accuracy of IUS to endoscopy and magnetic resonance enterography with an ability to be repeated as a monitor of treatment response for tight control monitoring.

Rosa Roxburghii Tratt Fruit Extract Prevents Dss-Induced Ulcerative Colitis in Mice by Modulating the Gut Microbiota and the IL-17 Signaling Pathway

Ulcerative colitis (UC) is a non-specific inflammatory bowel illness characterized by intestinal mucosal barrier degradation, inflammation, oxidative damage, and gut microbiota imbalances. Rosa roxburghii Tratt Fruit extract (RRTE) was extracted from Rosa roxburghii Tratt fruit, exhibiting an excellent prevention effect against UC; RRTE could prevent the damage of DSS-induced human normal colonic epithelial (NCM 460) cells, especially in cell viability and morphology, and oxidative damage. Additionally, in UC mice, RRTE could limit the intestinal mucosal barrier by increasing the expression of intestinal tight junction proteins and mucin, reducing inflammation and oxidative damage in colon tissue. More importantly, RRTE can increase the abundance of beneficial bacteria to regulate gut microbiota such as Ruminococcus, Turicibacter, and Parabacteroides, and reduce the abundance of harmful bacteria such as Staphylococcus and Shigella. Furthermore, transcriptomics of colonic mucosal findings point out that the beneficial effect of RRTE on UC could be attributed to the modulation of inflammatory responses such as the IL-17 and TNF signaling pathways. The qPCR results confirm that RRTE did involve the regulation of several genes in the IL-17 signaling pathway. In conclusion, RRTE could prevent DSS-induced damage both in vitro and in vivo.

Targeting Desulfovibrio vulgaris flagellin-induced NAIP/NLRC4 inflammasome activation in macrophages attenuates ulcerative colitis

INTRODUCTION

The perturbations of gut microbiota could interact with excessively activated immune responses and play key roles in the etiopathogenesis of ulcerative colitis (UC). Desulfovibrio, the most predominant sulfate reducing bacteria (SRB) resided in the human gut, was observed to overgrow in patients with UC. The interactions between specific gut microbiota and drugs and their impacts on UC treatment have not been demonstrated well.

OBJECTIVES

This study aimed to elucidate whether Desulfovibrio vulgaris (D. vulgaris, DSV) and its flagellin could activate nucleotide-binding oligomerization domain-like receptors (NLR) family of apoptosis inhibitory proteins (NAIP) / NLR family caspase activation and recruitment domain-containing protein 4 (NLRC4) inflammasome and promote colitis, and further evaluate the efficacy of eugeniin targeting the interaction interface of D. vulgaris flagellin (DVF) and NAIP to attenuate UC.

METHODS

The abundance of DSV and the occurrence of macrophage pyroptosis in human UC tissues were investigated. Colitis in mice was established by dextran sulfate sodium (DSS) and gavaged with DSV or its purified flagellin. NAIP/NLRC4 inflammasome activation and macrophage pyroptosis were evaluated in vivo and in vitro. The effects of eugeniin on blocking the interaction of DVF and NAIP/NLRC4 and relieving colitis were also assessed.

RESULTS

The abundance of DSV increased in the feces of patients with UC and was found to be associated with disease activity. DSV and its flagellin facilitated DSS-induced colitis in mice. Mechanistically, RNA sequencing showed that gene expression associated with inflammasome complex and pyroptosis was upregulated after DVF treatment in macrophages. DVF was further demonstrated to induce significant macrophage pyroptosis in vitro, depending on NAIP/NLRC4 inflammasome activation. Furthermore, eugeniin was screened as an inhibitor of the interface between DVF and NAIP and successfully alleviated the proinflammatory effect of DVF in colitis.

CONCLUSION

Targeting DVF-induced NAIP/NLRC4 inflammasome activation and macrophage pyroptosis ameliorates UC. This finding is of great significance for exploring the gut microbiota-host interactions in UC development and providing new insights for precise treatment.

Oxysophocarpine suppresses TRAF6 level to ameliorate oxidative stress and inflammatory factors secretion in mice with dextran sulphate sodium (DSS) induced-ulcerative colitis

PURPOSE

Ulcerative colitis is an inflammation-related disease with a high recurrence risk. Oxysophocarpine (OSC) is a traditional Chinese medicine isolated from legumes and exerts vital functions on many human diseases. However, the OSC's role in ulcerative colitis has not been fully elucidated. This research aimed to investigate the OSC's impact on ulcerative colitis and its mechanisms.

METHODS

A mouse model of ulcerative colitis was induced by dextran sulphate sodium (DSS). The effect of OSC on ulcerative colitis was examined using Disease Activity Index detection, hematoxylin-eosin (HE) staining, and enzyme-linked immunosorbent assay (ELISA). Meanwhile, the mechanism of OSC in ulcerative colitis was assessed by immunohistochemistry assay, Western blot, HE staining, and ELISA.

RESULTS

For the OSC's function in ulcerative colitis, OSC increased the mice weight, decreased Disease Activity Index scores, and alleviated colitis cell infiltration and epithelial cell destruction in DSS-induced ulcerative colitis. Also, OSC mitigated oxidative stress (decreased PGE2, MPO levels, and increased SOD levels) and inflammation (decreased IL-6, TNF-α and IL-1β levels) in DSS-induced ulcerative colitis. For the OSC's mechanism in ulcerative colitis, OSC inhibited the level of tumor necrosis factor receptor-associated Factor 6 (TRAF6) and the phosphorylation of nuclear factor-κB (NF-κB). TRAF6 overexpression abolished the effect of OSC on DSS-induced colon injury and its associated oxidative stress and inflammatory properties in ulcerative colitis.

CONCLUSION

OSC decreased the TRAF6 level to reduce oxidative stress and inflammatory factors secretion in mice with DSS induced-ulcerative colitis.

The Role of Noninvasive Surrogates of Inflammation in Monitoring Pediatric Inflammatory Bowel Diseases: The Old and the New

Effectiveness of limited available therapies for pediatric inflammatory bowel disease has reached stagnation. Previous non-invasive monitoring strategies have relied upon cumbersome tools to evaluate clinical symptoms and biochemical markers that do not reflect endoscopic activity or respond quickly to treatments. Novel, patient-centric, and highly accurate, monitoring strategies with a focus on intestinal ultrasound for a direct, precise monitoring of activity to achieve disease modification are now possible. Ultimately, research on the optimal tight control monitoring strategies, individualized to each pediatric inflammatory bowel disease patient, are in development and offer a hope to potential therapeutic ceiling breakthrough on the horizon.

Emerging Therapies for Ulcerative Colitis: Updates from Recent Clinical Trials

Ulcerative colitis (UC) is a chronic and progressive inflammatory disorder that affects the colon. The advent of advanced therapies such as biologic agents and small molecules has revolutionized the management of UC. Despite the expanding therapeutic armamentarium of advanced therapies to treat UC, the overall net remission rates and durability of currently available agents are relatively low. This highlights the need for further drug development and more innovative clinical trial design. There are currently multiple emerging agents in the pipeline for the management of UC. This includes agents with alternative routes of administration such as oral or subcutaneous tumor necrosis factor inhibitors or novel mechanisms of action such as toll-like receptor 9 (TLR9) agonist cobitolimod and phosphodiesterase 4 inhibitor apremilast. In this review, we will highlight novel and emerging advanced therapies currently in the pipeline for the management of UC.

miR-200a attenuated oxidative stress, inflammation, and apoptosis in dextran sulfate sodium-induced colitis through activation of Nrf2

Introduction

Oxidative stress and inflammatory responses are critical factors in ulcerative colitis disease pathogenesis. Nuclear factor erythroid 2-related factor 2 (Nrf2) modulates oxidative stress and suppresses inflammatory responses, and the protective benefits of Nrf2 activation have been associated with the therapy of ulcerative colitis. MicroRNA-200a (miR-200a) could target Kelch-like ECH-associated protein 1 (Keap1) and activate the Nrf2-regulated antioxidant pathway. Nevertheless, whether miR-200a modulates the Keap1/Nrf2 pathway in dextran sulfate sodium (DSS)-induced colonic damage is unknown. Here, our research intends to examine the impact of miR-200a in the model of DSS-induced colitis.

Methods

Prior to DSS intervention, we overexpressed miR-200a in mice for four weeks using an adeno-associated viral (AAV) vector to address this problem. ELISA detected the concentration of inflammation-related cytokines. The genes involved in inflammatory reactions and oxidative stress were identified using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blot, and immunofluorescence. Moreover, we applied siRNAs to weakened Nrf2 expression to confirm the hypothesis that miR-200a provided protection via Nrf2.

Results

The present study discovered miR-200a down-regulation, excessive inflammatory activation, enterocyte apoptosis, colonic dysfunction, and Keap1/Nrf2 antioxidant pathway inactivation in mouse colitis and NCM460 cells under DSS induction. However, our data demonstrated that miR-200a overexpression represses Keap1 and activates the Nrf2 antioxidant pathway, thereby alleviating these adverse alterations in animal and cellular models. Significantly, following Nrf2 deficiency, we failed to observe the protective benefits of miR-200a against colonic damage.

Discussion

Taken together, through activating the Keap1/Nrf2 signaling pathway, miR-200a protected against DSS-induced colonic damage. These studies offer an innovative therapeutic approach for ulcerative colitis.

The role of Nrf2 in the pathogenesis and treatment of ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease involving mainly the colorectal mucosa and submucosa, the incidence of which has been on the rise in recent years. Nuclear factor erythroid 2-related factor 2 (Nrf2), known for its key function as a transcription factor, is pivotal in inducing antioxidant stress and regulating inflammatory responses. Numerous investigations have demonstrated the involvement of the Nrf2 pathway in maintaining the development and normal function of the intestine, the development of UC, and UC-related intestinal fibrosis and carcinogenesis; meanwhile, therapeutic agents targeting the Nrf2 pathway have been widely investigated. This paper reviews the research progress of the Nrf2 signaling pathway in UC.

Recent Advances and Potential Multi-Omics Approaches in the Early Phases of Inflammatory Bowel Disease

Inflammatory bowel disease leads to debilitating gastrointestinal symptoms and reduced quality of life, resulting in a significant burden on healthcare utilization and costs. Despite substantial advancements in diagnosis and treatment, there may still be considerable delays in diagnosing some patients. To reduce disease progression before the full disease spectrum appears and improve prognostic outcomes, several strategies have concentrated on early intervention and prevention. Recent evidence shows that initial immune response changes and endoscopic lesions may exist for years before diagnosis, implying the existence of a preclinical phase of inflammatory bowel disease comparable to findings in other immune-mediated disorders. In this review, we highlight the most relevant findings regarding preclinical inflammatory bowel disease and the prospective role of novel omics techniques in this field.

Identifying biomarkers associated with the diagnosis of ulcerative colitis via bioinformatics and machine learning

BACKGROUND

Ulcerative colitis (UC) is an idiopathic inflammatory disease with an increasing incidence. This study aimed to identify potential UC biomarkers and associated immune infiltration characteristics.

METHODS

Two datasets (GSE87473 and GSE92415) were merged to obtain 193 UC samples and 42 normal samples. Using R, differentially expressed genes (DEGs) between UC and normal samples were filtered out, and their biological functions were investigated using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. Promising biomarkers were identified using least absolute shrinkage selector operator regression and support vector machine recursive feature elimination, and their diagnostic efficacy was evaluated through receiver operating characteristic (ROC) curves. Finally, CIBERSORT was used to investigate the immune infiltration characteristics in UC, and the relationship between the identified biomarkers and various immune cells was examined.

RESULTS

We found 102 DEGs, of which 64 were significantly upregulated, and 38 were significantly downregulated. The DEGs were enriched in pathways associated with interleukin-17, cytokine-cytokine receptor interaction and viral protein interactions with cytokines and cytokine receptors, among others. Using machine learning methods and ROC tests, we confirmed DUOX2, DMBT1, CYP2B7P, PITX2 and DEFB1 to be essential diagnostic genes for UC. Immune cell infiltration analysis revealed that all five diagnostic genes were correlated with regulatory T cells, CD8 T cells, activated and resting memory CD4 T cells, activated natural killer cells, neutrophils, activated and resting mast cells, activated and resting dendritic cells and M0, M1 and M2 macrophages.

CONCLUSIONS

DUOX2, DMBT1, CYP2B7P, PITX2 and DEFB1 were identified as prospective biomarkers for UC. A new perspective on understanding the progression of UC may be provided by these biomarkers and their relationship with immune cell infiltration.

miR-146a-5p regulates autophagy and NLRP3 inflammasome activation in epithelial barrier damage in the in vitro cell model of ulcerative colitis through the RNF8/Notch1/mTORC1 pathway

Ulcerative colitis (UC) is a chronic inflammatory disease affecting the colon that can be influenced by microRNAs (miRNAs). This study aims to investigate the impact of miR-146a-5p on lipopolysaccharide (LPS)-induced Caco-2/HT-29 cell autophagy and NLRP3 inflammasome activation and the underlying mechanism, with the aim of identifying potential therapeutic targets. We used LPS to establish Caco-2/HT-29 cell models and measured cell viability by CCK-8. The levels of miR-146a-5p, RNF8, markers of NLRP3 inflammasome activation and autophagy, proteins involved in the Notch1/mTORC1 pathway, and inflammatory factors were assessed by RT-qPCR, Western blot, and ELISA. Intestinal epithelial barrier function was evaluated by measuring transepithelial electrical resistance. Autophagic flux was measured using tandem fluorescent-labeled LC3. miR-146a-5p was highly-expressed in LPS-induced Caco-2/HT-29 cells, and autophagy flux was blocked at the autolysosomal stage after LPS induction. Inhibition of miR-146a-5p suppressed NLRP3 inflammasome activation, reduced intestinal epithelial barrier damage, and facilitated autophagy inhibition in LPS-induced Caco-2/HT-29 cells. The autophagy inhibitor NH4Cl partially nullified the inhibitory effects of miR-146a-5p inhibition on NLRP3 inflammation activation. miR-146a-5p targeted RNF8, and silencing RNF8 partly abrogated the action of miR-146a-5p inhibition on promoting autophagy and inhibiting NLRP3 inflammasome activation. miR-146a-5p inhibition suppressed the Notch1/mTORC1 pathway activation by upregulating RNF8. Inhibition of the Notch1/mTORC1 pathway partially nullified the function of silencing RNF8 on inhibiting autophagy and bolstering NLRP3 inflammasome activation. In conclusion, miR-146a-5p inhibition may be a potential therapeutic approach for UC, as it facilitates autophagy of LPS-stimulated Caco-2/HT-29 cells, inhibits NLRP3 inflammasome activation, and reduces intestinal epithelial barrier damage by upregulating RNF8 and suppressing the Notch1/mTORC1 pathway.

In situ polyphenol-adhesive hydrogel enhanced the noncarcinogenic repairing of KGF on the gut epithelial barrier on TNBS-induced colitis rats

Ulcerative colitis (UC) is a chronic recurrent disease affecting the gastrointestinal tract especially colorectum. Keratinocyte growth factor (KGF) plays the vital roles in maintaining the colonic mucosal barrier. The poor stability and off-target of KGF were two hindering factors for its clinical application. Herein, in situ hydrogel (PE) with mucoadhesive ability was constructed by using temperature-sensitive poloxamer and EGCG as hydrogel-forming material and adhesive enhancer, respectively. Incorporation of EGCG led to the slight decrease of the gelled temperature and shortened the gelled time of PE hydrogel. When the concentration of EGCG is 0.1 %, PE hydrogel exhibits the suitable viscosity of 280 ± 20 Pa·s and the strong adhesive force of 725 ± 25 mN. KGF was soluble in cold PE solution to obtain KGF-loaded PE hydrogel (KGF@PE). PE hydrogel could improve the stability of KGF in vitro. KGF@PE not only could recover greatly the body weight of TNBS-induced rats but also repair their colonic morphology and goblet cell function. Moreover, the potential of repairing the epithelial barrier was indicated by upregulating tight junction proteins. Importantly, the safety of KGF@PE hydrogel for colitis was also confirmed on AOM/DSS-induced mice models. Conclusively, KGF@PE may be a promising therapeutic platform without obvious side effect for ulcerative colitis.

Compatibility between cold-natured medicine CP and hot-natured medicine AZ synergistically mitigates colitis mice through attenuating inflammation and restoring gut barrier

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a nonspecific intestinal inflammation with complex pathogenesis. Traditional Chinese Medicine (TCM) formula consists of several TCM herbs following the principle of herbal property and compatibility. Our previous studies found that Huanglian Ganjiang decoction (HGD) exhibited anti-colitis capacity and the compatibility between hot-natured medicine and cold-natured medicine was main compatibility. However, the association between compatibility mechanism of HGD and its anti-colitis effect has not been fully illustrated yet.

AIM OF STUDY

Here, we would explore whether cold-natured medicine Coptis chinensis Franch. plus Phellodendron chinense C.K.Schneid. (CP) and hot-natured medicine Angelica sinensis (Oliv.) Diels plus Zingiber officinale Roscoe (AZ) in HGD respectively produce different impacts on UC, and exert synergistic effect on UC together.

MATERIALS AND METHODS

UPLC/MS-MS was used to qualitatively analyze chemical profiles of CP, AZ and CPAZ extracts. CPAZ-UC target network was constructed using network pharmacology. Colitis mice was induced by 3% DSS for 7 days and treated with CP, AZ and CPAZ for another 7 days. The levels of multiple cytokines and proportions of innate and adaptive immune cells were determined to assess inflammatory profiles. The leakage of FITC-dextran, expressions of tight junction proteins were detected for evaluation of gut barrier function.

RESULTS

CP, AZ and CPAZ could improve symptoms of colitis mice. CP showed superiority in reducing proportions of pro-inflammatory immune cells M1 cells, neutrophils, Th1 and Th17 cells, and levels of pro-inflammatory cytokines IFN-γ, IL-6, IL-10, TNF-α. In the contrast, AZ had advantage of elevating ratios of anti-inflammatory immune cells M2 and Treg cells as well as the production of anti-inflammatory cytokines IL-10 and TGF-β. In addition, CP and AZ synergistically regulated M1/M2 macrophage polarization and the following IL-6, IL-10, TNF-α, IFN-γ production, thereby restoring intestinal mucosal barrier.

CONCLUSION

Taken together, our study first demonstrated that cold-natured medicine CP and hot-natured medicine AZ took on different functions in treatment of colitis mice. Meanwhile, they exhibited synergistic effect on the alleviation of intestinal inflammation and reinforcement of gut barrier function and integrity.

Disease clearance in ulcerative colitis: Setting the therapeutic goals for future in the treatment of ulcerative colitis

Ulcerative colitis, one of the phenotypic patterns of inflammatory bowel disease, should be considered a progressive disease with an increased risk of complications if intestinal inflammation is not adequately controlled. The advent of new lines of treatment for this condition has changed and expanded the therapeutic goals to modify its natural history and evolution. The concept of "disease clearance" in ulcerative colitis aims to achieve clinical and biological remission as well as mucosal healing (endoscopic, histological, and in future molecular) in these patients. This review provides the available data on each of the goals of disease clearance in ulcerative colitis to be considered for application in clinical practice in the coming years.

Exosomal-miR-129-2-3p derived from Fusobacterium nucleatum-infected intestinal epithelial cells promotes experimental colitis through regulating TIMELESS-mediated cellular senescence pathway

Fusobacterium nucleatum (Fn) infection is known to exacerbate ulcerative colitis (UC). However, the link between Fn-infected intestinal epithelial cell (IEC)-derived exosomes (Fn-Exo) and UC progression has not been investigated. Differentially expressed miRNAs in Fn-Exo and non-infected IECs-derived exosomes (Con-Exo) were identified by miRNA sequencing. Then, the biological role and mechanism of Fn-Exo in UC development were determined in vitro and in vivo. We found that exosomes delivered miR-129-2-3p from Fn-infected IECs into non-infected IECs, exacerbating epithelial barrier dysfunction and experimental colitis. Mechanically, Fn-Exo induces DNA damage via the miR-129-2-3p/TIMELESS axis and subsequently activates the ATM/ATR/p53 pathway, ultimately promoting cellular senescence and colonic inflammation. In conclusion, Exo-miR-129-2-3p/TIMELESS/ATM/ATR/p53 pathway aggravates cellular senescence, barrier damage, and experimental colitis. The current study revealed a previously unknown regulatory pathway in the progression of Fn-infectious UC. Furthermore, Exosomal-miR-129-2-3p in serum and TIMELESS may function as novel potential diagnostic biomarkers for UC and Fn-high-UC.

Low Adherence is Associated with Chronic Active Disease in Ulcerative Colitis: A Retrospective Study from a Single Referral Center

PURPOSE

New therapeutic approaches for ulcerative colitis (UC) are now available, but there is still no robust evidence for predictors of poor outcomes. We aimed to evaluate the factors associated with a chronic active UC disease course.

PATIENTS AND METHODS

Data of all UC outpatients followed for at least 3 years after diagnosis between 2005 and 2018 were retrospectively collected. The primary aim was to identify risk factors for chronic active disease 3 years after diagnosis. Moreover, the following variables were investigated: proximal disease extension or disease regression, proctocolectomy, early use of biologics (BIO) or immunomodulators (IMM), hospitalization, colorectal cancer, and adherence. We defined adherence as both, taking the prescribed therapy and constancy in scheduled follow-up visits.

RESULTS

A total of 345 UC patients followed for a median period of 82 months were included. Patients with extensive colitis at diagnosis had a higher rate of chronic active disease 3 years after diagnosis (p<0.012) together with a higher rate of surgery (p<0.001) at maximum follow-up. Patients with pancolitis showed significant disease regression over time (51%) without differences in treatment. The only factor associated with chronic active disease was non-adherence (p < 0.03; OR 0.49, 95% CI: 0.26-0.95). Adherent patients developed chronic active disease (p<0.025) less frequently but did receive more frequent IMM (p<0.045) or BIO (p<0.009) therapy.

CONCLUSION

Patients diagnosed with pancolitis were more likely to have chronic active disease and to undergo colectomy. The only predictor for developing chronically active UC regardless of disease extension was the lack of adherence to therapy within the first 3 years after diagnosis, underlining the importance of tight control of UC patients and the need to timely identify potential risk factors for non-adherence.

Honokiol Ameliorates DSS-Induced Mouse Colitis by Inhibiting Inflammation and Oxidative Stress and Improving the Intestinal Barrier

Ulcerative colitis (UC) is a multifactor intestinal disease with increased morbidity. Recently, pleiotropic drugs with exact biosafety have been urgently needed. Honokiol (HKL) is the major bioactive component of traditional Chinese medicine "Houpu," with almost no toxic effects and approved anti-inflammation, antioxidant, antispasmodic, etc. effects. This study examined the therapeutic effect of HKL in dextran sulfate sodium- (DSS-) induced experimental colitis. In vivo, C57BL/6 mice received 3% DSS for seven days to generate UC, and HKL was pretreated for five days and given during the whole DSS-induced period. In vitro, RAW264.7 macrophages were stimulated with lipopolysaccharide (LPS) to induce inflammation, and mouse colon epithelial cells (MCEC) were treated with HKL or pretreated with HKL and then stimulated with LPS-induced macrophage supernate to investigate the barrier enhancement roles. HKL significantly ameliorated disease activity index (DAI), colon length, and histopathological scores in DSS-induced colitis. The inflammatory mediators of interleukin 1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX2) were decreased, and the tight conjunction proteins were increased in the HKL-treated group both in vivo and in vitro. Above all, HKL can relieve experimental UC through anti-inflammation, antioxidant, and epithelial barrier enhancement roles. These effects were associated with peroxisome proliferator-activated receptor γ (PPARγ)/nuclear factor-κB (NF-κB) p65, sirtuin3 (SIRT3)/adenosine 5'-monophosphate- (AMP-) activated protein kinase (AMPK), and nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase 1 (HO1) signaling pathways. In conclusion, after further clinical studies, HKL may be a promising drug for UC.

Discovery and Validation of Potential Serum Biomarkers with Pro-Inflammatory and DNA Damage Activities in Ulcerative Colitis: A Comprehensive Untargeted Metabolomic Study

Ulcerative colitis is a type of non-specific inflammatory bowel disease with unclear etiology. It is considered a progressive disease with risks of bowel motility disorders, anorectal dysfunction, and even colorectal cancer. Commonly used diagnostic markers have poor specificity and cannot predict the development of ulcerative colitis. In this study, 77 serum samples (31 patients, 46 healthy controls) were analyzed using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry and 31 metabolites with significant level changes were found, revealing the relationship of ulcerative colitis to disturbed glutathione metabolism and caffeine metabolism. In addition, pyroglutamic acid, a biomarker of cervical cancer and gastric cancer, was identified with elevated levels in the serum of ulcerative colitis patients. The role of pyroglutamic acid was further analyzed, and the results indicated its positive correlation with the upregulation of inflammatory factors and increased levels of phosphorylated histone H2AX (γH2AX) in IEC-6 cells, which are related to DNA damage. All these results suggest that pyroglutamic acid is not only a biomarker for distinguishing ulcerative colitis status, but that it is also a potential effective metabolite that promotes the transformation of ulcerative colitis to colorectal cancer.

Natural history and impact of irritable bowel syndrome-type symptoms in inflammatory bowel disease during 6 years of longitudinal follow-up

BACKGROUND

The long-term natural history and impact of irritable bowel syndrome (IBS)-type symptoms on outcomes in inflammatory bowel disease (IBD) are uncertain.

AIM

To assess this in a longitudinal follow-up study of patients in secondary care METHODS: We assessed the natural history of IBS-type symptoms in IBD via Rome III criteria applied at baseline, and 2 and 6 years. We defined longitudinal disease activity as the need for glucocorticosteroids or flare, escalation, hospitalisation or intestinal resection. To assess healthcare utilisation, we recorded the number of outpatient clinic attendances and investigations. We also collected anxiety, depression and somatoform symptom scores and quality of life scores during follow-up.

RESULTS

Among 125 individuals with Rome III data at all three time points, only 41 (32.8%) never reported IBS-type symptoms. Fifteen patients (12.0%) had IBS-type symptoms at baseline that resolved, 19 (15.2%) had fluctuating symptoms, 35 (28.0%) had new-onset symptoms, and 15 (12.0%) had persistent symptoms. Among more than 300 patients with IBD activity data, IBS-type symptoms were not associated with an increased likelihood of the need for glucocorticosteroids or flare, escalation, hospitalisation or intestinal resection. However, the mean numbers of outpatient appointments and endoscopic investigations were significantly higher among those with IBS-type symptoms. Anxiety, depression and somatoform symptom scores were significantly higher, and quality of life scores were significantly lower, in those reporting IBS-type symptoms at least once during the study.

CONCLUSIONS

IBS-type symptoms affected more than two-thirds of patients with IBD during >6 years of follow-up and were associated with increased healthcare utilisation, and worse anxiety, depression, somatoform symptom and quality of life scores, but not adverse disease activity outcomes.

(Re)Appraising Remission in Ulcerative Colitis

As the therapeutic targets in ulcerative colitis (UC) shift from control of symptoms to mucosal healing and prevention of disease complications like disability, colectomy, and cancer, the definition of remission has evolved. The current definition of clinical remission is variable and is determined by the clinical context in which it is being used. This results in skepticism and uncertainty about the true meaning of the term "clinical remission." In this review, the authors reexamine the definition of clinical remission and propose a novel approach to define remission in UC.

Dynamic Changes in Gut Microbiome of Ulcerative Colitis: Initial Study from Animal Model

Background

An animal model of DSS-induced UC has been widely used in basic research, and the dysbiosis of gut microbiome is one of the important pathogenetic mechanisms of DSS-induced UC, but its dynamic changes and correlation with inflammatory factors are not clear yet.

Methods

Clinical signs and tissue damage degree of C57BL/6 ulcerative colitis mice model induced by different concentrations of DSS were compared with that of normal mice, and finally the optimal concentration of DSS was determined. Then we analyzed the sequencing results of gut microbiome and inflammatory factors to determine the dynamic patterns of gut microbiome and their correlation with the inflammatory factors.

Results

DSS at 2.5% and 3.0% concentration could cause intestinal injury and induce colitis. However, 3.0% DSS resulted in higher mortality. In addition, there were dynamic changes of gut microbiome in DSS-induced UC model: the relative abundance of intestinal flora increased first and then decreased in Bacteroides, Parabacteroides, Romboutsia, Clostridium_sensu_stricto_1, Lachnospiraceae_NK4A136_group, norank_f_norank_o_Clostridia_UCG-014, Parasutterella, and decreased first and then increased in Lactobacillus, Muribaculum, norank_f_Muribaculaceae, in addition, Bifidobacterium, Coriobacteriaceae_UCG-002 and Enterorhabdus did not change in the first 14 days but increased significantly on day 21. Moreover, inflammatory cytokines were closely associated with the imbalance of the intestinal microbiota in mice with UC: most pathogenic bacteria in the intestinal tract of the UC animal model were positively correlated with pro-inflammatory factors and negatively correlated with anti-inflammatory factors, while beneficial bacteria were the opposite.

Conclusion

Intestinal microecology plays an important role in DSS-induced UC model, and the relative abundance of gut microbiome changes dynamically in the occurrence and development of ulcerative colitis.