Temporally Distinct Functions of the Cytokines IL-12 and IL-23 Drive Chronic Colon Inflammation in Response to Intestinal Barrier Impairment

Supplementation of low-protein diets with plant protein and probiotics enhances muscle health by regulating gut microbiota and metabolomic profiles in SAMP8 mice

Muscle health is crucial, especially for aging populations. This study investigates how plant protein and probiotic supplementation in a low-protein (LP) diet affects the gut microbiota, metabolome, and muscle health in aging SAMP8 mice, emphasizing the gut-muscle axis in older populations. Twenty-four 8-month-old male SAMP8 mice were divided into four groups: control (CON, standard diet), low-protein (LP), LP supplemented with plant protein (LP + P), and LP supplemented with plant protein and probiotics (LP + P + B). The experimental treatment lasted 8 weeks. Results showed that, by week 6, body weight increased significantly in all LP groups, with a trend toward higher body fat. Protein utilization and muscle strength improved significantly in the supplemented groups compared to the LP group (P < 0.05). The LP group showed elevated levels of inflammatory cytokines (IL-12p70, IL-6, TNF-α) (P < 0.05) in serum, which were reduced in the supplemented groups, especially in the LP + P + B group (P < 0.05). Gene expression related to muscle protein synthesis (mTOR, S6K1) and oxidative stress (CAT, Nrf2) was upregulated in the LP group but downregulated in the supplemented groups (P < 0.05). Immune-related genes followed similar patterns, with inflammation markers being significantly reduced after supplementation (P < 0.05). After supplementation, fecal beneficial bacteria (Bifidobacterium, Roseburia) and metabolites (butyric acid, indole-3-propionic acid, kyotorphin) increased, indicating enhanced gut health (P < 0.05). Specific bacterial species were correlated with metabolites and immune markers, highlighting their role in immune modulation (P < 0.05). These results show that supplementing plant protein and probiotics into an LP diet improved muscle strength, reduced inflammation, optimized gut microbiota, and boosted beneficial metabolism. The findings suggest that plant protein and probiotics can maintain muscle health and regulate immune responses in the elderly.

Are single nucleotide polymorphisms underutilized for guiding treatment of inflammatory bowel disease?

Inflammatory bowel disease (IBD), encompassing Crohn's disease (CD), ulcerative colitis (UC) and IBD unclassified (IBDU), significantly impacts quality of life. Despite significant advances in the management of the conditions, responses to treatments vary greatly, and this is due partly to our natural genetic variation. Here we will review the evidence for whether single nucleotide polymorphisms (SNPs) have the potential to guide treatment decisions for people with IBD. We will first consider SNPs that exhibit strong associations with IBD pathogenesis and their relevance to epithelial barrier integrity, cytokine production, and immune system function. Then, we will cover those SNPs implicated in altering response to our various current IBD therapeutics, including the recently implemented drugs ustekinumab and tofacitinib. Finally, we will explore lesser-known SNPs that exhibit complex relationships with the disease and which may be undervalued as pharmacogenetic tools. Overall, it will be demonstrated that SNPs associated with IBD pathology are largely distinct from those predicting response to treatments and that new discoveries of clinically useful tools can be expected from therapy-focused investigations. Given the growing list of treatments available, we argue that beneficial personalization of treatments based on SNPs is still underutilized.

Gut-homing and intestinal TIGITnegCD38+ memory T cells acquire an IL-12-induced, ex-Th17 pathogenic phenotype in a subgroup of Crohn's disease patients with a severe disease course

CD4+ memory T cell (TM) reactivation drives chronicity in inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis. Defects driving loss of TM regulation likely differ between patients but remain undefined. In health, approximately 40 % of circulating gut-homing CD38+TM express co-inhibitory receptor T-cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT). TIGIT+CD38+TM have regulatory function while TIGITnegCD38+TM are enriched in IFN-γ-producing cells. We hypothesized TIGITnegCD38+TM are inflammatory and drive disease in a subgroup of IBD patients. We characterized TIGIT+CD38+TM in a uniquely large cohort of pediatric IBD patients from time of diagnosis into adulthood. Circulating TIGITnegCD38+TM frequencies were higher in a subgroup of therapy-naïve CD patients with high plasma IFN-γ and a more severe disease course. TIGITnegCD38+TM were highly enriched in HLA-DR+ and ex-Th17/Th1-like cells, high producers of IFN-γ. Cultures of healthy-adult-stimulated TM identified IL-12 as the only IBD-related inflammatory cytokine to drive the pathogenic ex-Th17-TIGITnegCD38+ phenotype. Moreover, IL12RB2 mRNA expression was higher in TIGITnegCD38+TM than TIGIT+CD38+TM, elevated in CD biopsies compared to controls, and correlated with severity of intestinal inflammation. Overall, we argue that in a subgroup of pediatric CD, increased IL-12 signaling drives reprogramming of Th17 to inflammatory Th1-like TIGITnegCD38+TM and causes more severe disease.

Probiotic nanocomposite materials with excellent resistance, inflammatory targeting, and multiple efficacies for enhanced treatment of colitis in mice

The occurrence of inflammatory bowel disease (IBD) is relevant to impaired intestinal mucosal barrier and disordered gut microbiota, subsequently leading to excessive production of reactive oxygen species (ROS) and elevated levels of inflammatory factors. Traditional therapies focus on inhibiting inflammation, but the vast majority involve non-targeted systemic administration, whose long-term use may result in potential side effects. Oral microbial therapy has exhibited great application prospects currently in IBD treatment; however, its progress has been slowed by issues with deficient bioavailability, poor targeting of colitis, and low therapeutic efficacy. Consequently, it is exceedingly desirable to develop a strategy by which probiotics can be endowed with additional anti-inflammatory and antioxidant properties, as well as enhanced targeting of the inflamed intestine. Herein, we present an innovative therapeutic strategy for encapsulating probiotic Bacillus coagulans spores with rosmarinic acid (RA) and silk fibroin (SF). Probiotics in spore morphology possessed strong gastrointestinal environmental resistance; RA alleviated oxidative damage by scavenging ROS and inhibited inflammatory responses; SF assisted probiotics release and colonize in the inflamed intestine. We demonstrated the therapeutic efficacy of probiotic composite materials in a colitis mouse model, which significantly alleviated a series of colitis symptoms, inhibited inflammatory cytokine storms, restored the balance of the gut microbiota, and downregulated inflammation-related signaling pathways. We are optimistic that the utilization of therapeutic nanocoating to modify probiotics will open up novel avenues for future microbial therapy targeting IBD.

Activated type 17 helper T cells affect tofacitinib treatment outcomes

The incidence of ulcerative colitis (UC) is on the rise also in Japan. Simultaneously, therapeutic options, including biologics and Janus kinase (JAK) inhibitors, have significantly expanded over the past decade. Although tofacitinib (TOF), one of JAK inhibitors, is a viable option for patients with moderate to severe UC, there is insufficient data to predict responsiveness of TOF treatment. The present study aimed to determine whether the infiltration of IL-17 A-positive mononuclear cells into the colonic mucosa can predict responsiveness to TOF treatment. Patients with UC who underwent TOF treatment were divided into responder and failure groups. Subsequently, we conducted a comparative analysis to identify differences in the infiltration of IL-17 A-positive cells into the colonic mucosa through immunohistochemical examination of colon biopsy samples. The proportion of IL-17 A positive mononuclear cells in colon biopsy samples was significantly higher in the failure group than among responders (38.2% vs. 21.2%). Consistent with this finding, our re-analysis of RNA sequence datasets available in the Gene Expression Omnibus (GEO) database suggested that TOF exerts a more pronounced influence on Th1 cells compared with IL-17-producing Th17 cells. In summary, an abundance of IL-17 A-positive mononuclear cells in the colonic mucosa has the potential to predict the responsiveness to TOF treatment.

Butyrolactone-I from marine fungi alleviates intestinal barrier damage caused by DSS through regulating lactobacillus johnsonii and its metabolites in the intestine of mice

Butyrolactone-I (BTL-1), a secondary metabolite from the marine fungus Aspergillus terreus, exhibits numerous biological activities. Previous research has indicated that Butyrolactone-I alleviates intestinal epithelial inflammation via the TLR4/NF-κB and MAPK pathways. However, the mechanisms underlying its protection against intestinal barrier damage remain unclear. This study aims to further elucidate these mechanisms. We observed that BTL-1 administration increased the abundance of Lactobacillus johnsonii (LJ) in both in vivo and in vitro experiments, prompting an investigation into the effects of LJ and its metabolites on DSS-induced inflammatory bowel disease (IBD). The results demonstrated that BTL-1 significantly upregulated tight junction (TJ) and adherens junction (AJ) proteins, maintained intestinal barrier integrity, and alleviated DSS-induced IBD in mice. These effects were associated with the proliferation of LJ and its metabolites, such as butyric and propionic acids, and the inhibition of the MAPK signaling pathway in the colon. Interestingly, administering LJ alone produced a protective effect against DSS-induced IBD similar to that observed with BTL-1. Furthermore, butyric acid, a metabolite of LJ, also upregulated TJ/AJ proteins in intestinal epithelial cells through the MAPK signaling pathway. Our findings suggest that BTL-1 regulates intestinal flora, promotes LJ proliferation, protects intestinal barrier integrity, increases the concentrations of butyric and propionic acids, and ultimately inhibits the activation of the MAPK signaling pathway in mice to alleviate IBD. Therefore, BTL-1 could potentially be used as a natural drug to prevent IBD and maintain intestinal flora balance. We explored how butyrolactone-I exerts a preventive effect on IBD through intestinal bacteria (Lactobacillus johnsonii).

Differential Efficacy of Advanced Therapies in Inducing Remission in Ulcerative Colitis Based on Prior Exposure to TNF Antagonists

BACKGROUND AND AIMS

We sought to ascertain how prior exposure to tumor necrosis factor (TNF) antagonists impacts treatment response with various classes of advanced therapies in patients with ulcerative colitis (UC), through a systematic review and meta-analysis.

METHODS

Through a systematic review of multiple databases through June 30, 2024, we identified 17 randomized controlled trials in 8871 adults with moderate-severe UC who were treated with different advanced therapies vs placebo, and reported efficacy in induction of clinical remission, stratified by prior exposure to TNF antagonists. We calculated the ratio of odds ratio of achieving remission with active drug vs placebo, in TNF antagonist-naïve vs TNF antagonist-exposed patients. We grouped advanced therapies based on primary mechanism of action: lymphocyte trafficking inhibitors (anti-integrins and sphingosine-1 phosphate [S1P] receptor modulators), anti-interleukins (interleukin-12/23 antagonist and selective interleukin-23 antagonists) and Janus kinase inhibitors.

RESULTS

Lymphocyte trafficking inhibitors were more efficacious in TNF antagonist-naïve vs exposed patients (5 trials; odds ratio [OR], 1.88; 95% confidence interval [CI], 1.02-3.49), whereas JAK inhibitors were less efficacious in TNF antagonist-naïve vs exposed patients (6 trials; ratio of OR, 0.47; 95% CI, 0.22-1.01). No significant difference was observed in efficacy of selective interleukin-23 antagonists vs placebo in TNF antagonist-naïve vs exposed patients (6 trials; ratio of OR, 1.07; 95% CI, 0.64-1.80). There was minimal heterogeneity across analyses.

CONCLUSION

There is significant heterogeneity of treatment efficacy with different advanced therapies in inducing remission in patients with UC based on prior exposure to TNF antagonists, with plausible potentiation of JAK inhibitors and attenuation of lymphocyte trafficking inhibitors. Future studies on the mechanistic basis for these observations are warranted.

Key Interleukins in Inflammatory Bowel Disease-A Review of Recent Studies

Inflammatory bowel disease (IBD) is an immune disorder of the gastrointestinal tract with a complex aetiopathogenesis, whose development is influenced by many factors. The prevalence of IBD is increasing worldwide, in both industrialized and developing countries, making IBD a global health problem that seriously affects quality of life. In 2019, there were approximately 4.9 million cases of IBD worldwide. Such a large number of patients entails significant healthcare costs. In the treatment of patients with IBD, the current therapeutic target is mucosal healing, as intestinal inflammation often persists despite resolution of abdominal symptoms. Treatment strategies include amino salicylates, corticosteroids, immunosuppressants, and biologic therapies that focus on reducing intestinal mucosal inflammation, inducing and prolonging disease remission, and treating complications. The American College of Gastroenterology (ACG) guidelines also indicate that nutritional therapies may be considered in addition to other therapies. However, current therapeutic approaches are not fully effective and are associated with various limitations, such as drug resistance, variable efficacy, and side effects. As the chronic inflammation that accompanies IBD is characterized by infiltration of a variety of immune cells and increased expression of a number of pro-inflammatory cytokines, including IL-6, TNF-α, IL-12, IL-23 and IFN-γ, new therapeutic approaches are mainly targeting immune pathways. Interleukins are one of the molecular targets in IBD therapy. Interleukins and related cytokines serve as a means of communication for innate and adaptive immune cells, as well as nonimmune cells and tissues. These cytokines play an important role in the pathogenesis and course of IBD, making them promising targets for current and future therapies. In our work, we review scientific studies published between January 2022 and November 2024 describing the most important interleukins involved in the pathogenesis of IBD. Some of the papers present new data on the precise role that individual interleukins play in IBD. New clinical data have also been provided, particularly on blocking interleukin 23 and interleukin 1beta. In addition, several new approaches to the use of different interleukins in the treatment of IBD have been described in recent years.

Impact of chronic stress on intestinal mucosal immunity in colorectal cancer progression

Chronic stress is a significant risk factor that contributes to the progression of colorectal cancer (CRC) and has garnered considerable attention in recent research. It influences the distribution and function of immune cells within the intestinal mucosa through the "brain-gut" axis, altering cytokine and chemokine secretion and creating an immunosuppressive tumor microenvironment. The intestine, often called the "second brain," is particularly susceptible to the effects of chronic stress. Cytokines and chemokines in intestinal mucosal immunity（IMI） are closely linked to CRC cells' proliferation, metastasis, and drug resistance under chronic stress. Recently, antidepressants have emerged as potential therapeutic agents for CRC, possibly by modulating IMI to restore homeostasis and exert anti-tumor effects. This article reviews the role of chronic stress in promoting CRC progression via its impact on intestinal mucosal immunity, explores potential targets within the intestinal mucosa under chronic stress, and proposes new approaches for CRC treatment.

The effects of Cordyceps polysaccharides on ischemic brain injury in rats via intervening with IL-23/IL-17 axis and the intestinal barrier

Cordyceps polysaccharide (CSP) has been shown to exhibit anti-inflammatory and antioxidant effects, with potential applications in ischemic stroke. This work is to explore the interventional potential of CSP in MCAO rats and the effects on the intestinal and cerebral IL-23/IL-17 axis. We conducted pharmacological experiments and mechanism exploration in MCAO rats. Our research showed that CSP improved the neurological function and cerebral pathological morphology, reduced cerebral infarction volume and water content in MCAO rats. We also found that CSP significantly decreased the IL-1β, TNF-α and IL-6 in the ischemic brain and enhanced the ability of MCAO rats to resist oxidative stress. Additionally, CSP improved intestinal barrier, inhibited the activation of the TLR4/Myd88/NF-κβ signaling pathway and IL-23/IL-17 axis. The study results demonstrated the effectiveness of CSP in interfering with MCAO rats. The mechanism appears to be related to protecting the intestinal barrier and inhibiting the IL-23/IL-17 axis.

Deciphering the role of host-gut microbiota crosstalk via diverse sources of extracellular vesicles in colorectal cancer

Colorectal cancer is the most common type of cancer in the digestive system and poses a major threat to human health. The gut microbiota has been found to be a key factor influencing the development of colorectal cancer. Extracellular vesicles are important mediators of intercellular communication. Not only do they regulate life activities within the same individual, but they have also been found in recent years to be important mediators of communication between different species, such as the gut microbiota and the host. Their preventive, diagnostic, and therapeutic value in colorectal cancer is being explored. The aim of this review is to provide insights into the complex interactions between host and gut microbiota, particularly those mediated through extracellular vesicles, and how these interactions affect colorectal cancer development. In addition, the potential of extracellular vesicles from various body fluids as biomarkers was evaluated. Finally, we discuss the potential, challenges, and future research directions of extracellular vesicles in their application to colorectal cancer. Overall, extracellular vesicles have great potential for application in medical processes related to colorectal cancer, but their isolation and characterization techniques, intercellular communication mechanisms, and the effectiveness of their clinical application require further research and exploration.

IL-23 exerts dominant pathogenic functions in Crohn's disease-ileitis

Crohn's disease (CD), a main form of Inflammatory Bowel Disease (IBD) is a chronic inflammatory disorder, mainly affecting the ileum. Interleukin (IL)-12 and IL-23 are both targeted by Ustekinumab, a commonly used monoclonal antibody for IBD treatment. However, their specific roles in ileitis have not been extensively explored. Here, we utilized the TnfΔΑRE model of CD-ileitis to probe the functions of IL-12 and IL-23 by employing genetically deficient mice for their respective subunits. Our findings highlight that IL-23, rather than IL-12, plays a pivotal role in the progression of ileitis. IL-23 deficiency resulted in reduced immune cell infiltration in the ileum, and decreased expression of effector cytokines downstream of IL-23 signaling. Interestingly, expanding CD14+ neutrophils were highly expressing Il23a in the inflamed ileum. Furthermore, the deletion of IL-12 conferred modest additional protection only in the absence of IL-23, suggesting potential compensatory mechanisms between these cytokines. Furthermore, our study suggests that IL-23 may function independently of IL-17, as Il17a deletion exacerbated murine ileitis, consistent with clinical studies in human CD patients using anti-IL-17 inhibitors. This research underscores the significance of targeting IL-23 in CD-ileitis, while the concurrent targeting of both IL-12 and IL-23 should be also considered as an advantageous therapeutic approach.

Enhancing gut barrier integrity: Upregulation of tight junction proteins by chitosan oligosaccharide through the ERK1/2 signaling pathway

OBJECTIVES

This study aimed to explore the protective mechanism of chitosan oligosaccharide (COS) against lipopolysaccharide (LPS)-induced inflammatory responses in IEC-6 cells and dextran sodium sulfate (DSS)-induced colitis in mice.

METHODS

The cell inflammation model was constructed by LPS in vitro and enteritis model by DSS in vivo.

RESULTS

Following LPS exposure, IEC-6 cell proliferation significantly decreased, epithelial cell integrity was compromised, and TNF-α and IL-1β levels were increased. However, COS pretreatment reversed these changes. In vivo, DSS-treated mice exhibited evident pathological alterations, including heightened inflammatory levels and significantly decreased expression of tight junction proteins and critical proteins in the Mitogen activated proteins kinase signaling pathway. Nevertheless, COS administration notably reduced inflammatory levels and increased the expression of tight junction proteins and key proteins in the Mitogen activated proteins kinase signaling pathway.

CONCLUSIONS

Our findings suggest that COS safeguards gut barrier integrity by upregulating tight junction proteins through the ERK1/2 signaling pathway. Therefore, COS has emerged as a promising candidate for novel drug interventions against inflammatory bowel disease.

Parenteral Nutrition, Inflammatory Bowel Disease, and Gut Barrier: An Intricate Plot

Malnutrition poses a critical challenge in inflammatory bowel disease, with the potential to detrimentally impact medical treatment, surgical outcomes, and general well-being. Parenteral nutrition is crucial in certain clinical scenarios, such as with patients suffering from short bowel syndrome, intestinal insufficiency, high-yielding gastrointestinal fistula, or complete small bowel obstruction, to effectively manage malnutrition. Nevertheless, research over the years has attempted to define the potential effects of parenteral nutrition on the intestinal barrier and the composition of the gut microbiota. In this narrative review, we have gathered and analyzed findings from both preclinical and clinical studies on this topic. Based on existing evidence, there is a clear correlation between short- and long-term parenteral nutrition and negative effects on the intestinal system. These include mucosal atrophic damage and immunological and neuroendocrine dysregulation, as well as alterations in gut barrier permeability and microbiota composition. However, the mechanistic role of these changes in inflammatory bowel disease remains unclear. Therefore, further research is necessary to effectively address the numerous gaps and unanswered questions pertaining to these issues.

Biomarkers for Personalizing IBD Therapy: The Quest Continues

Despite recent advances in the understanding of the pathogenesis of inflammatory bowel diseases (IBD) and advent of multiple targeted therapies, approximately one-third of patients are primary non-responders to initiated treatment, and half of patients lose response over time. There is currently a lack of available biomarkers that would prognosticate therapeutic effectiveness of these advanced therapies. This is partly explained by insufficient characterization of the functional roles assumed by the chosen molecular targets during disease treatment. There is a dire need for validated objective biomarkers, which could be indicators of a biological process, that can be applied in clinical practice to assist us in assigning therapies to patients with the highest probability of response. An appropriate molecular and cellular characterization that accounts for the interindividual differences in drug efficacy and potential side effects would help to guide clinicians in the management of patients with IBD and represent a major step to tailor a more personalized approach to treatment. An appropriate combination of complementing biomarkers should ideally incorporate a multimodal analysis in which genetic, microbial, transcriptional, proteomic, metabolic, and immunologic data are combined to enable a truly personalized approach. This would classify patients into disease subgroups according to molecular characteristics, which would enable us to initiate the most appropriate therapeutic substance. Emergence of single-cell technologies to map the intestinal cellular landscape and multiomic approaches have helped to further dissect the pathogenic mechanisms of mucosal inflammation, but the clinical translation of potential biomarkers remains cumbersome, and an ongoing concerted effort by the IBD community is required.

Inflammatory Gene Panel Guiding the Study of Genetics in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a complex disease that develops through a sequence of molecular events that are still poorly defined. This process is driven by a multitude of context-dependent genes that play different roles based on their environment. The complexity and multi-faceted nature of these genes make it difficult to study the genetic basis of IBD. The goal of this article is to review the key genes in the pathophysiology of IBD and highlight new technology that can be used in further research. This paper examines Nanostring RNA probe technology, which uses tissue analyzed without the use of enzymes, transcription, or amplification. Nanostring offers several panels of genes to test, including an inflammation panel of 234 genes. This article analyzes this panel and reviews the literature for each gene's effect in IBD for use as a framework to review the pathophysiology of the disease. The panel was narrowed to 26 genes with significant evidence of mechanistic potential in IBD, which were then categorized into specific areas of pathogenesis. These include gut barrier breakdown, inappropriate recognition of commensal bacteria, immune cell activation, proinflammatory cytokine release, and subsequent impairment of the anti-inflammatory response. The eventual goal of this paper is the creation of a customized panel of IBD genes that can be used to better understand the genetic mechanism of IBD and aid in the development of future therapies in IBD.

Challenges in IBD Research 2024: Preclinical Human IBD Mechanisms

Preclinical human inflammatory bowel disease (IBD) mechanisms is one of 5 focus areas of the Challenges in IBD Research 2024 document, which also includes environmental triggers, novel technologies, precision medicine, and pragmatic clinical research. Herein, we provide a comprehensive overview of current gaps in inflammatory bowel diseases research that relate to preclinical research and deliver actionable approaches to address them with a focus on how these gaps can lead to advancements in IBD interception, remission, and restoration. The document is the result of multidisciplinary input from scientists, clinicians, patients, and funders and represents a valuable resource for patient-centric research prioritization. This preclinical human IBD mechanisms section identifies major research gaps whose investigation will elucidate pathways and mechanisms that can be targeted to address unmet medical needs in IBD. Research gaps were identified in the following areas: genetics, risk alleles, and epigenetics; the microbiome; cell states and interactions; barrier function; IBD complications (specifically fibrosis and stricturing); and extraintestinal manifestations. To address these gaps, we share specific opportunities for investigation for basic and translational scientists and identify priority actions.

Regulation of mouse digestive function, intestinal mucosal barrier function, and inflammatory reaction by lycium barbarum polysaccharide pathway through myosin light chain kinase

This research investigated the impacts of lycium barbarum polysaccharide (LBP) on the digestive function, intestinal mucosal barrier function, inflammatory response, and myosin light chain kinase (MLCK) signaling pathway in immunosuppressed mice. 70 mg/kg cyclophosphamide was injected into abdomen for the preparation of immune suppression model. Healthy BALB/c mice served as control for the analysis of the differences in gastrointestinal motility and absorptive capacity, intestinal mucosal barrier function, the phagocytic ability of abdominal macrophages, serum immune factor and inflammatory factor levels, and the activation status of the MLCK signaling pathway after continuous gavage with 100 mg/kg LBP. Results revealed a decrease in d-xylose content, phagocytic rate, index of abdominal macrophages, and spleen index in the serum and urine of model mice compared to those of controls. In addition, levels of IgA, IgG, IgM, IL-6 (interleukin-6), IL-12, and interferon-γ (IFN-γ) decreased, while MLCK and myosin light chain (MLC) levels rose (P < 0.01). Versus those in Model group, urine d-xylose content, phagocytic rate, index of abdominal macrophages, spleen index, and the levels of IgA, IgG, IgM, IL-6, IL-12, and IFN-γ of mice undergoing the gavage with LBP increased, while MLCK and p-MLC levels declined (P < 0.05). In conclusion, LBP improved digestive absorption and immune function of immunosuppressed mice and regulated intestinal mucosal barrier immune system by inhibiting MLCK signaling pathway activation.

IL-23 past, present, and future: a roadmap to advancing IL-23 science and therapy

Interleukin (IL)-23, an IL-12 cytokine family member, is a hierarchically dominant regulatory cytokine in a cluster of immune-mediated inflammatory diseases (IMIDs), including psoriasis, psoriatic arthritis, and inflammatory bowel disease. We review IL-23 biology, IL-23 signaling in IMIDs, and the effect of IL-23 inhibition in treating these diseases. We propose studies to advance IL-23 biology and unravel differences in response to anti-IL-23 therapy. Experimental evidence generated from these investigations could establish a novel molecular ontology centered around IL-23-driven diseases, improve upon current approaches to treating IMIDs with IL-23 inhibition, and ultimately facilitate optimal identification of patients and, thereby, outcomes.

Epithelial-derived interleukin-23 promotes oral mucosal immunopathology

At mucosal surfaces, epithelial cells provide a structural barrier and an immune defense system. However, dysregulated epithelial responses can contribute to disease states. Here, we demonstrated that epithelial cell-intrinsic production of interleukin-23 (IL-23) triggers an inflammatory loop in the prevalent oral disease periodontitis. Epithelial IL-23 expression localized to areas proximal to the disease-associated microbiome and was evident in experimental models and patients with common and genetic forms of disease. Mechanistically, flagellated microbial species of the periodontitis microbiome triggered epithelial IL-23 induction in a TLR5 receptor-dependent manner. Therefore, unlike other Th17-driven diseases, non-hematopoietic-cell-derived IL-23 served as an initiator of pathogenic inflammation in periodontitis. Beyond periodontitis, analysis of publicly available datasets revealed the expression of epithelial IL-23 in settings of infection, malignancy, and autoimmunity, suggesting a broader role for epithelial-intrinsic IL-23 in human disease. Collectively, this work highlights an important role for the barrier epithelium in the induction of IL-23-mediated inflammation.

Comprehensive overview of novel chemical drugs for ulcerative colitis: focusing on phase 3 and beyond

INTRODUCTION

Despite the growing number of highly efficacious biologics and chemical drugs for ulcerative colitis (UC), steroid-free disease control is still difficult to achieve in subgroups of patients due to refractoriness, adverse events, primary or secondary failure. New treatments are therefore still required in order to optimize clinical management of patients with UC.

AREAS COVERED

The efficacy and safety of both currently available and newly developed small molecules have been summarized. The PubMed database and clinicaltrials.gov were considered in order to search for phase 2b and 3 trials on new chemical drugs for UC. The study drugs reviewed included Janus kinases (JAK) and sphingosine-1-phosphate receptor (S1Pr) inhibitors, α4 integrin antagonist, and micro-RNA-124 upregulators.

EXPERT OPINION

Rapidity of onset, low immunogenicity, and safety are the main characteristics of small molecules currently available or under evaluation for treatment patients with UC. Among the currently available chemical drugs, the selective JAK and the S1Pr inhibitors are characterized by a good safety profile combined with the ability to induce clinical remission in UC. A relatively low frequency of endoscopic improvement and healing currently appears associated with their use, being higher in UC patients treated with S1Pr inhibitor Etrasimod. Overall, additional new safe and effective drugs are still required in order to optimize disease control in a larger majority of UC patients.

Research progress of Ustekinumab in the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic, recurrent gastrointestinal disorder with elusive etiology. Interleukin-12 (IL-12) and IL-23 have emerged as key proinflammatory mediators/cytokines in IBD pathogenesis. Ustekinumab (UST), targeting IL-12 and IL-23, has demonstrated promising efficacy and safety in the treatment of IBD. Recently, UST has become increasingly favored as a potential first-line treatment option. This review delineates UST's mechanism of action, its clinical applications in IBD, including the response rates, strategies for dose optimization for case of partial or lost response, and potential adverse events. This review aims to offer a comprehensive understanding of UST's role as a therapeutic option in IBD management.

Transient gestational hypothyroxinemia accelerates and enhances ulcerative colitis-like disorder in the male offspring

Introduction

Gestational hypothyroxinemia (HTX) is a condition that occurs frequently at the beginning of pregnancy, and it correlates with cognitive impairment, autism, and attentional deficit in the offspring. Evidence in animal models suggests that gestational HTX can increase the susceptibility of the offspring to develop strong inflammation in immune-mediated inflammatory diseases. Ulcerative colitis (UC) is a frequent inflammatory bowel disease with unknown causes. Therefore, the intensity of ulcerative colitis-like disorder (UCLD) and the cellular and molecular factors involved in proinflammatory or anti-inflammatory responses were analyzed in the offspring gestated in HTX (HTX-offspring) and compared with the offspring gestated in euthyroidism (Control-offspring).

Methods

Gestational HTX was induced by the administration of 2-mercapto-1-methylimidazole in drinking water to pregnant mice during E10-E14. The HTX-offspring were induced with UCLD by the acute administration of dextran sodium sulfate (DSS). The score of UCLD symptomatology was registered every day, and colon histopathology, immune cells, and molecular factors involved in the inflammatory or anti-inflammatory response were analyzed on day 6 of DSS treatment.

Results

The HTX-offspring displayed earlier UCLD pathological symptoms compared with the Control-offspring. After 6 days of DSS treatment, the HTX-offspring almost doubled the score of the Control-offspring. The histopathological analyses of the colon samples showed signs of inflammation at the distal and medial colon for both the HTX-offspring and Control-offspring. However, significantly more inflammatory features were detected in the proximal colon of the HTX-offspring induced with UCLD compared with the Control-offspring induced with UCLD. Significantly reduced mRNA contents encoding for protective molecules like glutamate-cysteine ligase catalytic subunit (GCLC) and mucin-2 (MUC-2) were found in the colon of the HTX-offspring as compared with the Control-offspring. Higher percentages of Th17 lymphocytes were detected in the colon tissues of the HTX-offspring induced or not with UCLD as compared with the Control-offspring.

Discussion

Gestational HTX accelerates the onset and increases the intensity of UCLD in the offspring. The low expression of MUC-2 and GCLC together with high levels of Th17 Lymphocytes in the colon tissue suggests that the HTX-offspring has molecular and cellular features that favor inflammation and tissue damage. These results are important evidence to be aware of the impact of gestational HTX as a risk factor for UCLD development in offspring.

A Narrative Review of Cytokine Networks: Pathophysiological and Therapeutic Implications for Inflammatory Bowel Disease Pathogenesis

Inflammatory bowel disease (IBD) is a lifelong inflammatory immune mediated disorder, encompassing Crohn's disease (CD) and ulcerative colitis (UC); however, the cause and specific pathogenesis of IBD is yet incompletely understood. Multiple cytokines produced by different immune cell types results in complex functional networks that constitute a highly regulated messaging network of signaling pathways. Applying biological mechanisms underlying IBD at the single omic level, technologies and genetic engineering enable the quantification of the pattern of released cytokines and new insights into the cytokine landscape of IBD. We focus on the existing literature dealing with the biology of pro- or anti-inflammatory cytokines and interactions that facilitate cell-based modulation of the immune system for IBD inflammation. We summarize the main roles of substantial cytokines in IBD related to homeostatic tissue functions and the remodeling of cytokine networks in IBD, which may be specifically valuable for successful cytokine-targeted therapies via marketed products. Cytokines and their receptors are validated targets for multiple therapeutic areas, we review the current strategies for therapeutic intervention and developing cytokine-targeted therapies. New biologics have shown efficacy in the last few decades for the management of IBD; unfortunately, many patients are nonresponsive or develop therapy resistance over time, creating a need for novel therapeutics. Thus, the treatment options for IBD beyond the immune-modifying anti-TNF agents or combination therapies are expanding rapidly. Further studies are needed to fully understand the immune response, networks of cytokines, and the direct pathogenetic relevance regarding individually tailored, safe and efficient targeted-biotherapeutics.

Colitis-associated carcinogenesis: crosstalk between tumors, immune cells and gut microbiota

Colorectal cancer (CRC) is the third most common cancer worldwide. One of the main causes of colorectal cancer is inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD). Intestinal epithelial cells (IECs), intestinal mesenchymal cells (IMCs), immune cells, and gut microbiota construct the main body of the colon and maintain colon homeostasis. In the development of colitis and colitis-associated carcinogenesis, the damage, disorder or excessive recruitment of different cells such as IECs, IMCs, immune cells and intestinal microbiota play different roles during these processes. This review aims to discuss the various roles of different cells and the crosstalk of these cells in transforming intestinal inflammation to cancer, which provides new therapeutic methods for chemotherapy, targeted therapy, immunotherapy and microbial therapy.

Oral Ritlecitinib and Brepocitinib for Moderate-to-Severe Ulcerative Colitis: Results From a Randomized, Phase 2b Study

BACKGROUND & AIMS

The efficacy and safety of ritlecitinib (oral JAK3/TEC family kinase inhibitor) and brepocitinib (oral TYK2/JAK1 inhibitor) as induction therapy were assessed in patients with active, moderate-to-severe ulcerative colitis.

METHODS

This phase 2b, parallel-arm, double-blind umbrella study randomized patients with moderate-to-severe ulcerative colitis to receive 8-week induction therapy with ritlecitinib (20, 70, 200 mg), brepocitinib (10, 30, 60 mg), or placebo once daily. The primary endpoint was total Mayo Score (TMS) at week 8.

RESULTS

Of 319 randomized patients, 317 received ritlecitinib (n = 150), brepocitinib (n = 142), or placebo (n = 25). The placebo-adjusted mean TMSs (90% confidence interval) at week 8 were -2.0 (-3.2 to -0.9), -3.9 (-5.0 to -2.7), and -4.6 (-5.8 to -3.5) for ritlecitinib 20, 70, and 200 mg, respectively (P = .003, P < .001, P < .001), and -1.8 (-2.9 to -0.7), -2.3 (-3.4 to -1.1), and -3.2 (-4.3 to -2.1) for brepocitinib 10, 30, and 60 mg, respectively (P = .009, P = .001, P < .001). Estimates (90% confidence interval) for placebo-adjusted proportions of patients with modified clinical remission at week 8 were 13.7% (0.5%-24.2%), 32.7% (20.2%-45.3%), and 36.0% (23.6%-48.6%) for ritlecitinib 20, 70, and 200 mg, respectively, and 14.6% (1.9%-25.7%), 25.5% (11.0%-38.1%), and 25.5% (11.0%-38.1%) for brepocitinib 10, 30, and 60 mg, respectively. Adverse events were mostly mild, and there were no serious cases of herpes zoster infection. Infections were observed with brepocitinib (16.9% [12.5%-23.7%]), ritlecitinib (8.7% [5.2%-13.4%]), and placebo (4.0% [0.2%-17.6%]). One death due to myocardial infarction (ritlecitinib) and 1 thromboembolic event (brepocitinib) occurred; both were considered unrelated to study drug.

CONCLUSIONS

Ritlecitinib and brepocitinib induction therapies were more effective than placebo for the treatment of moderate-to-severe active ulcerative colitis, with an acceptable short-term safety profile.

CLINICALTRIALS

gov number: NCT02958865.

Horizon scanning: new and future therapies in the management of inflammatory bowel disease

The current mainstay treatment modalities for inflammatory bowel disease (IBD) include immunomodulators (methotrexate and thiopurines), biologics (antitumour necrosis factor alpha (TNF-α) being the most commonly used) and other monoclonal antibodies such as the anti-integrins and anti-interleukins (IL-12/23). While ideally treatment should be initiated early in the disease process to avoid relapses and complications, the major recurring issue continues to be primary and secondary loss of response, with often 'diminishing returns' in terms of efficacy for the next line of therapies prescribed for patients with IBD. Additional concerns include the long-term risk factors such as malignancy and susceptibility to infections. Recently, there has been an influx of new and emerging medications entering the market that are showing promising efficacy results in patients with moderate-to-severe disease who have previously failed to respond to multiple drugs. This review will focus on these novel and emerging therapies-in essence, 'horizon scanning'-which includes the antiadhesion agents, cytokine inhibitors, Janus kinase inhibitors, phosphodiesterase inhibitors, sphingosine-1 phosphate receptor modulators and MicroRNA-124 (miR-124) upregulators.

Immune microenvironment profiling of normal appearing colorectal mucosa biopsied over repeat patient visits reproducibly separates lynch syndrome patients based on their history of colon cancer

Introduction

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC), increasing lifetime risk of CRC by up to 70%. Despite this higher lifetime risk, disease penetrance in LS patients is highly variable and most LS patients undergoing CRC surveillance will not develop CRC. Therefore, biomarkers that can correctly and consistently predict CRC risk in LS patients are needed to both optimize LS patient surveillance and help identify better prevention strategies that reduce risk of CRC development in the subset of high-risk LS patients.

Methods

Normal-appearing colorectal tissue biopsies were obtained during repeat surveillance colonoscopies of LS patients with and without a history of CRC, healthy controls (HC), and patients with a history of sporadic CRC. Biopsies were cultured in an ex-vivo explant system and their supernatants were assayed via multiplexed ELISA to profile the local immune signaling microenvironment. High quality cytokines were identified using the rxCOV fidelity metric. These cytokines were used to perform elastic-net penalized logistic regression-based biomarker selection by computing a new measure - overall selection probability - that quantifies the ability of each marker to discriminate between patient cohorts being compared.

Results

Our study demonstrated that cytokine based local immune microenvironment profiling was reproducible over repeat visits and sensitive to patient LS-status and CRC history. Furthermore, we identified sets of cytokines whose differential expression was predictive of LS-status in patients when compared to sporadic CRC patients and in identifying those LS patients with or without a history of CRC. Enrichment analysis based on these biomarkers revealed an LS and CRC status dependent constitutive inflammatory state of the normal appearing colonic mucosa.

Discussion

This prospective pilot study demonstrated that immune profiling of normal appearing colonic mucosa discriminates LS patients with a prior history of CRC from those without it, as well as patients with a history of sporadic CRC from HC. Importantly, it suggests the existence of immune signatures specific to LS-status and CRC history. We anticipate that our findings have the potential to assess CRC risk in individuals with LS and help in preemptively mitigating it by optimizing surveillance and identifying candidate prevention targets. Further studies are required to validate our findings in an independent cohort of LS patients over multiple visits.

IL-12 and IL-23 pathway inhibition in inflammatory bowel disease

Interleukin-12 (IL-12) and interleukin-23 (IL-23), which belong to the IL-12 family of cytokines, have a key role in intestinal homeostasis and inflammation and are implicated in the pathogenesis of inflammatory bowel disease. Upon their secretion by antigen-presenting cells, they exert both pro-inflammatory and anti-inflammatory receptor-mediated effects. An increased understanding of these biological effects, particularly the pro-inflammatory effects mediated by IL-12 and IL-23, has led to the development of monoclonal antibodies that target a subunit common to IL-12 and IL-23 (p40; targeted by ustekinumab and briakinumab), or the IL-23-specific subunit (p19; targeted by risankizumab, guselkumab, brazikumab and mirikizumab). This Review provides a summary of the biology of the IL-12 family cytokines IL-12 and IL-23, discusses the role of these cytokines in intestinal homeostasis and inflammation, and highlights IL-12- and IL-23-directed drug development for the treatment of Crohn's disease and ulcerative colitis.

Hydrogel‐Based Artificial Mucosa Restores Local Immune and Microbial Homeostasis for Treating Ulcerative Colitis

Ulcerative colitis (UC) is a common inflammatory bowel disease driven by the dyshomeostasis of intestinal immune system and microbiota, but its treatment options are limited due to impaired epithelial barrier integrity and function. Herein, a multifunctional biomimetic hydrogel is developed as artificial colonic mucosa, which can readily establish a bioadhesive barrier at the ulcer site and restore local immune and microbial homeostasis to exert potent anti‐inflammatory effect. The hydrogel framework is generated through the thrombin‐mediated activation and polymerization of fibrinogen that resembles natural blood coagulation mechanism. During this process, the antibacterial agent Ag+ is used for the crosslinking between the generated fibrin units and dopamine/thiol‐modified hyaluronic acid biopolymers via Ag+‐thiol coordination to convey enhanced bioadhesiveness, while the interconnected porous network is employed to encapsulate basic fibroblast growth factor (bFGF) and alanyl‐glutamine (ALG) for mucosa regeneration. The hydrogel stably adheres to the ulcer site to protect and repair the damaged epithelium and establishes an anti‐inflammatory microenvironment by inducing locoregional M1‐to‐M2 macrophage repolarization while eliminating harmful gut flora, which can act in a cooperative manner to substantially alleviate UC symptoms. The biomimetic hydrogel here presents a promising approach for effective UC therapy in the clinics.

The role of IL-23/IL-17 axis in ischemic stroke from the perspective of gut-brain axis

Bidirectional communication between central nervous system (CNS) and intestine is mediated by nerve, endocrine, immune and other pathways in gut-brain axis. Many diseases of CNS disturb the homeostasis of intestine and gut microbiota. Similarly, the dysbiosis of intestinal and gut microbiota also promotes the progression and deterioration of CNS diseases. IL-23/IL-17 axis is an important inflammatory axis which is widely involved in CNS diseases such as experimental autoimmune encephalomyelitis (EAE), multiple sclerosis (MS), and ischemic stroke (IS). Attributing to the long anatomically distances between ischemic brain and gut, previous studies on IL-23/IL-17 axis in IS are rarely focused on intestinal tissues. However, recent studies have found that IL-17⁺T cells in CNS mainly originate from intestine. The activation and migration of IL-17⁺T cells to CNS is likely to be affected by the altered intestinal homeostasis. These studies promoted the attention of IL-23/IL-17 axis and gut-brain axis. IS is difficult to treat because of its extremely complex pathological mechanism. This review mainly discusses the relationship between IL-23/IL-17 axis and IS from the perspective of gut-brain axis. By analyzing the immune pathways in gut-brain axis, the activation of IL-23/IL-17 axis, the roles of IL-23/IL-17 axis in gut, CNS and other systems after stoke, this review is expected to provide new enlightenments for the treatment strategies of IS.

Immune Microenvironment Profiling of Normal Appearing Colorectal Mucosa Biopsied Over Repeat Patient Visits Reproduciably Separates Lynch Syndrome Patients Based on Their History of Colon Cancer

Introduction

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC), increasing lifetime risk of CRC by up to 70%. Despite this higher lifetime risk, disease penetrance in LS patients is highly variable and most LS patients undergoing CRC surveillance will not develop CRC. Therefore, biomarkers that can correctly and consistently predict CRC risk in LS patients are needed to both optimize LS patient surveillance and help identify better prevention strategies that reduce risk of CRC development in the subset of high-risk LS patients.

Methods

Normal-appearing colorectal tissue biopsies were obtained during repeat surveillance colonoscopies of LS patients with and without a history of CRC, healthy controls (HC), and patients with a history of sporadic CRC. Biopsies were cultured in an ex-vivo explant system and their supernatants were assayed via multiplexed ELISA to profile the local immune signaling microenvironment. High quality cytokine signatures were identified using rx COV fidelity metric. These signatures were used to perform biomarker selection by computing their selection probability based on penalized logistic regression.

Results

Our study demonstrated that cytokine based local immune microenvironment profiling was reproducible over repeat visits and sensitive to patient LS-status and CRC history. Furthermore, we identified sets of biomarkers whose differential expression was predictive of LS-status in patients when compared to sporadic CRC patients and in identifying those LS patients with or without a history of CRC. Enrichment analysis based on these biomarkers revealed an LS and CRC status dependent constitutive inflammatory state of the normal appearing colonic mucosa.

Discussion

This prospective pilot study demonstrated that immune profiling of normal appearing colonic mucosa discriminates LS patients with a prior history of CRC from those without it, as well as patients with a history of sporadic CRC from HC. Importantly, it suggests existence of immune signatures specific to LS-status and CRC history. We anticipate that our findings have the potential to assess CRC risk in individuals with LS and help in preemptively mitigating it by optimizing surveillance and identifying candidate prevention targets. Further studies are required to validate our findings in an independent cohort of LS patients over multiple visits.

Exploring the Pipeline of Novel Therapies for Inflammatory Bowel Disease; State of the Art Review

Crohn’s disease (CD) and ulcerative colitis (UC), known as inflammatory bowel diseases (IBD), are characterized by chronic inflammation of the gastrointestinal tract. Over the last two decades, numerous medications have been developed and repurposed to induce and maintain remission in IBD patients. Despite the approval of multiple drugs, the major recurring issues continue to be primary non-response and secondary loss of response, as well as short- and long-term adverse events. Most clinical trials show percentages of response under 60%, possibly as a consequence of strict inclusion criteria and definitions of response. That is why these percentages appear to be more optimistic in real-life studies. A therapeutic ceiling has been used as a term to define this invisible bar that has not been crossed by any drug yet. This review highlights novel therapeutic target agents in phases II and III of development, such as sphingosine-1-phosphate receptor modulators, selective Janus kinase inhibitors, anti-interleukins, and other small molecules that are currently under research until 1 January 2023. Emerging treatments for CD and UC that have just received approval or are undergoing phase III clinical trials are also discussed in this review.

Differential involvement of LUBAC-mediated linear ubiquitination in intestinal epithelial cells and macrophages during intestinal inflammation

Disruption of the intestinal epithelial barrier and dysregulation of macrophages are major factors contributing to the pathogenesis of inflammatory bowel diseases (IBDs). Activation of NF-κB and cell death are involved in maintaining intestinal homeostasis in a cell type-dependent manner. Although both are regulated by linear ubiquitin chain assembly complex (LUBAC)-mediated linear ubiquitination, the physiological relevance of linear ubiquitination to intestinal inflammation remains unexplored. Here, we used two experimental mouse models of IBD (intraperitoneal LPS and oral dextran sodium sulfate [DSS] administration) to examine the role of linear ubiquitination in intestinal epithelial cells (IECs) and macrophages during intestinal inflammation. We did this by deleting the linear ubiquitination activity of LUBAC specifically from IECs or macrophages. Upon LPS administration, loss of ligase activity in IECs induced mucosal inflammation and augmented IEC death. LPS-mediated death of LUBAC-defective IECs was triggered by TNF. IEC death was rescued by an anti-TNF antibody, and TNF (but not LPS) induced apoptosis of organoids derived from LUBAC-defective IECs. However, augmented TNF-mediated IEC death did not overtly affect the severity of colitis after DSS administration. By contrast, defective LUBAC ligase activity in macrophages ameliorated DSS-induced colitis by attenuating both infiltration of macrophages and expression of inflammatory cytokines. Decreased production of macrophage chemoattractant MCP-1/CCL2, as well as pro-inflammatory IL-6 and TNF, occurred through impaired activation of NF-κB and ERK via loss of ligase activity in macrophages. Taken together, these results indicate that both intraperitoneal LPS and oral DSS administrations are beneficial for evaluating epithelial integrity under inflammatory conditions, as well as macrophage functions in the event of an epithelial barrier breach. The data clarify the cell-specific roles of linear ubiquitination as a critical regulator of TNF-mediated epithelial integrity and macrophage pro-inflammatory responses during intestinal inflammation. © 2022 The Pathological Society of Great Britain and Ireland.

Development of a 32-gene signature using machine learning for accurate prediction of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic inflammatory condition caused by multiple genetic and environmental factors. Numerous genes are implicated in the etiology of IBD, but the diagnosis of IBD is challenging. Here, XGBoost, a machine learning prediction model, has been used to distinguish IBD from healthy cases following elaborative feature selection. Using combined unsupervised clustering analysis and the XGBoost feature selection method, we successfully identified a 32-gene signature that can predict IBD occurrence in new cohorts with 0.8651 accuracy. The signature shows enrichment in neutrophil extracellular trap formation and cytokine signaling in the immune system. The probability threshold of the XGBoost-based classification model can be adjusted to fit personalized lifestyle and health status. Therefore, this study reveals potential IBD-related biomarkers that facilitate an effective personalized diagnosis of IBD.

Fecal Luminal Factors from Patients with Gastrointestinal Diseases Alter Gene Expression Profiles in Caco-2 Cells and Colonoids

Previous in vitro studies have shown that the intestinal luminal content, including metabolites, possibly regulates epithelial layer responses to harmful stimuli and promotes disease. Therefore, we aimed to test the hypothesis that fecal supernatants from patients with colon cancer (CC), ulcerative colitis (UC) and irritable bowel syndrome (IBS) contain distinct metabolite profiles and establish their effects on Caco-2 cells and human-derived colon organoids (colonoids). The metabolite profiles of fecal supernatants were analyzed by liquid chromatography-mass spectrometry and distinguished patients with CC (n = 6), UC (n = 6), IBS (n = 6) and healthy subjects (n = 6). Caco-2 monolayers and human apical-out colonoids underwent stimulation with fecal supernatants from different patient groups and healthy subjects. Their addition did not impair monolayer integrity, as measured by transepithelial electrical resistance; however, fecal supernatants from different patient groups and healthy subjects altered the gene expression of Caco-2 monolayers, as well as colonoid cultures. In conclusion, the stimulation of Caco-2 cells and colonoids with fecal supernatants derived from CC, UC and IBS patients altered gene expression profiles, potentially reflecting the luminal microenvironment of the fecal sample donor. This experimental approach allows for investigating the crosstalk at the gut barrier and the effects of the gut microenvironment in the pathogenesis of intestinal diseases.

Pathogenesis-oriented therapy of psoriasis using biologics

INTRODUCTION

Psoriasis is currently regarded an immune-mediated inflammatory disease. The central pathogenic axis comprises interleukin-23, TH17-lymphocytes differentiating under its influence, and interleukin-17A as a key effector cytokine of these T-lymphocytes. All of these can selectively be targeted using biological therapies, thus potentially increasing efficacy and reducing adverse events when compared to conventional systemic therapeutics.

AREAS COVERED

We review the current concept of psoriasis as an immune-mediated inflammatory disease, assessing the evidence for a role of elements of the innate and adaptive immune system. We then correlate the pharmacological effects of biologics in psoriasis in light of the known physiologic as well as pathophysiological role of the respective targets. This is done on the basis of an extensive literature search of publications since 2018 which describe the role of the above-mentioned elements in health and disease or the effects of blocking these as an attempt to treat psoriasis.

EXPERT OPINION

Biologics targeting the above-mentioned central pathogenic axis provide a particularly effective and safe way to treat psoriasis. Given the impact of comorbidities on therapeutic decision-making, and the efficacy of some biologics also on certain comorbidities, these drugs represent a first step toward personalized medicine in the management of psoriasis.

Diet-induced modifications to human microbiome reshape colonic homeostasis in irritable bowel syndrome

Changes in microbiome composition are associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet, clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we infuse gut organ cultures with longitudinal microbiota samples collected from therapy-naive patients with irritable bowel syndrome (IBS) under a low-fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a pathway discovery platform for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of a low-FODMAP diet and reinforce the potential feasibility of microbiome-based therapies in IBS.

Roseburia intestinalis stimulates TLR5-dependent intestinal immunity against Crohn's disease

Background

Methods

Findings

Interpretation

Funding

The progress of protein synthesis factors eIFs, eEFs and eRFs in inflammatory bowel disease and colorectal cancer pathogenesis

Colorectal diseases are threatening human health, especially inflammatory bowel disease (IBD) and colorectal cancer (CRC). IBD is a group of chronic, recurrent and incurable disease, which may affect the entire gastrointestinal tract, increasing the risk of CRC. Eukaryotic gene expression is a complicated process, which is mainly regulated at the level of gene transcription and mRNA translation. Protein translation in tissue is associated with a sequence of steps, including initiation, elongation, termination and recycling. Abnormal regulation of gene expression is the key to the pathogenesis of CRC. In the early stages of cancer, it is vital to identify new diagnostic and therapeutic targets and biomarkers. This review presented current knowledge on aberrant expression of eIFs, eEFs and eRFs in colorectal diseases. The current findings of protein synthesis on colorectal pathogenesis showed that eIFs, eEFs and eRFs may be potential targets for CRC treatment.

Oral administration of human carbonic anhydrase I suppresses colitis in a murine inflammatory bowel disease model

The incidence of inflammatory bowel disease (IBD) is increasing; hence, effective treatments are warranted. The therapeutic effect of human carbonic anhydrase I (hCA I) in IBD remains unknown. Therefore, we investigated whether oral tolerization to hCA I would induce antigen-specific protection from intestinal inflammation in vivo. Severe combined immunodeficient mice received hCA I, keyhole limpet hemocyanin (KLH), or phosphate-buffered saline (PBS) orally for 7 days. Colons and mesenteric lymph nodes (MLNs) were collected 4 weeks after cell transfer. Additionally, the mechanisms underlying the therapeutic effects were investigated. The comparison between the effects of well-established drugs and hCA I oral administration was investigated. Oral administration of hCA I ameliorated colitis remarkably. hCA I reached the cecum and ameliorated colitis more effectively than mesalazine and similarly to prednisolone. Compared with PBS treatment, hCA I treatment reduced interleukin (IL)-17a, IL-6, and retinoic acid-related orphan receptor gamma t (RORγt) expression in the colon or MLNs; moreover, hCA I markedly reduced IL-6, IL-17, and interferon-gamma (IFN-γ) levels in the MLN. Oral administration of hCA I induced immune tolerance and suppressed colitis in vivo. Thus, hCA I administration could be proposed as a new treatment option for IBD.

Relationship of Serum IL-12 to Inflammation, Hematoma Volume, and Prognosis in Patients With Intracerebral Hemorrhage

Objective. Inflammatory cascades and hematomas after intracerebral hemorrhage (ICH) cause brain tissue and neuronal damage. Interleukin-12 (IL-12) promotes brain inflammation, and regulates coagulation mediated by red blood cells and platelets. This study was designed to investigate the relationship of serum IL-12 to inflammation, hematoma volume, and prognosis in ICH patients. Methods. We recruited patients with ICH within 12 hours of symptom onset (n = 209) and measured their serum IL-12 levels. Patients with an increased National Institute of Health stroke scale (NIHSS) score ≥4 were defined as early neurological deterioration, and modified rankin scale (mRS) score >2 at 3 months after intracerebral hemorrhage was defined as poor prognosis. Results. Levels of serum IL-12 was positively correlated with the admission of NIHSS scores (r = 0.535, $P<0.001$ ), hematoma volume (r = 0.608, $P<0.001$ ), serum CRP levels (r = 0.561, $P<0.001$ ), and serum TNF-α levels (r = 0.533, $P<0.001$ ) in 209 cases ICH patients. Levels of IL-12 in ICH patients with early neurological deterioration (median: 82.9 versus 65.8, $P<0.001$ ) or with poor prognosis (median: 79.0 versus 65.3, $P<0.001$ ) were all significantly higher than those in other ICH patients. In addition, serum IL-12 levels could be used to differentiate ICH patients at risk for early neurological deterioration with an AUC of 0.788 (95% CI: 0.717–0.858) or ICH patients at risk for suffering from an unfavorable outcome with an AUC of 0.787 (95% CI: 0.722–0.851). Conclusion. Elevated admission serum IL-12 levels are closely related to the inflammation, hematoma volume, and prognosis in ICH patients. Substantializing serum IL-12 levels is a prognostic biomarker for ICH.

Tackling Inflammatory Bowel Diseases: Targeting Proinflammatory Cytokines and Lymphocyte Homing

Inflammatory bowel diseases (IBDs) are characterized by chronic inflammatory disorders that are a result of an abnormal immune response mediated by a cytokine storm and immune cell infiltration. Proinflammatory cytokine therapeutic agents, represented by TNF inhibitors, have developed rapidly over recent years and are promising options for treating IBD. Antagonizing interleukins, interferons, and Janus kinases have demonstrated their respective advantages in clinical trials and are candidates for anti-TNF therapeutic failure. Furthermore, the blockade of lymphocyte homing contributes to the excessive immune response in colitis and ameliorates inflammation and tissue damage. Factors such as integrins, selectins, and chemokines jointly coordinate the accumulation of immune cells in inflammatory regions. This review assembles the major targets and agents currently targeting proinflammatory cytokines and lymphatic trafficking to facilitate subsequent drug development.

The ethanol extract of Periplaneta Americana L. improves ulcerative colitis induced by a combination of chronic stress and TNBS in rats

Purpose:

To investigate the effects of Periplaneta americana L. on ulcerative colitis (UC) induced by a combination of chronic stress (CS) and 2,4,6-trinitrobenzene sulfonic acid enema (TNBS) in rats.

Methods:

The experiment UC model with CS was established in rats by a combination of chronic restraint stress, excess failure, improper, and TNBS. The body weight, disease activity index (DAI), colonic mucosal injury index (CMDI), histopathological score (HS) and pro-inflammatory mediators were measured. The content of corticotropin-releasing hormone (CRH) in hypothalamus or adrenocorticotropic hormone (ACTH) and corticosteroids (CORT) in plasma were evaluated by enzyme-linked immunosorbent assay. The proportion of T lymphocyte subsets was detected by flow cytometry, and gut microbiota was detected by 16S rDNA amplicon sequencing.

Results:

Weight loss, DAI, CMDI, HS and proinflammatory mediators were reversed in rats by P. americana L. treatment after UC with CS. Increased epidermal growth factor (EGF) was observed in P. americana L. groups. In addition, P. americana L. could reduce the content of CRH and ACTH and regulate the ratio of CD3⁺, CD3⁺CD8⁺ and CD3⁺CD4⁺CD25⁺/CD4⁺ in spleen. Comparably, P. americana L. changes composition of gut microbiota.

Conclusions:

The ethanol extract of Periplaneta Americana L. improves UC induced by a combination of CS and TNBS in rats.

Evidence of a genetically driven metabolomic signature in actively inflamed Crohn's disease

Crohn's disease (CD) is characterised by chronic inflammation. We aimed to identify a relationship between plasma inflammatory metabolomic signature and genomic data in CD using blood plasma metabolic profiles. Proton NMR spectroscopy were achieved for 228 paediatric CD patients. Regression (OPLS) modelling and machine learning (ML) approaches were independently applied to establish the metabolic inflammatory signature, which was correlated against gene-level pathogenicity scores generated for all patients and functional enrichment was analysed. OPLS modelling of metabolomic spectra from unfasted patients revealed distinctive shifts in plasma metabolites corresponding to regions of the spectrum assigned to N-acetyl glycoprotein, glycerol and phenylalanine that were highly correlated (R² = 0.62) with C-reactive protein levels. The same metabolomic signature was independently identified using ML to predict patient inflammation status. Correlation of the individual peaks comprising this metabolomic signature of inflammation with pathogenic burden across 15,854 unselected genes identified significant enrichment for genes functioning within 'intrinsic component of membrane' (p = 0.003) and 'inflammatory bowel disease (IBD)' (p = 0.003). The seven genes contributing IBD enrichment are critical regulators of pro-inflammatory signaling. Overall, a metabolomic signature of inflammation can be detected from blood plasma in CD. This signal is correlated with pathogenic mutation in pro-inflammatory immune response genes.

Ustekinumab Tissue and Serum Levels in Patients With Crohn's Disease Are Closely Correlated Though Not Consistently Associated With Objective Response After Induction

BACKGROUND

Ustekinumab (UST), which targets p40/interleukin (IL)-23 and IL-12, is an effective treatment for Crohn's disease (CD). Therapeutic drug monitoring may optimize UST posology. The aim of this study was to investigate UST and IL-23 serum and tissue concentrations in relation to mucosal inflammation and treatment response at an early time point.

METHODS

CD patients starting UST between December 2016 and November 2018 were prospectively enrolled. Endoscopies were performed at baseline and week 16. UST and IL-23 serum and tissue concentrations were measured at week 16. Clinical and biochemical response were defined as decline of ≥3 points in Harvey-Bradshaw Index and reduction of ≥50% in fecal calprotectin levels. Endoscopic response was defined as a ≥50% decline in Simple Endoscopic Score or a decline of ≥1 points in Rutgeerts score. Histological remission was defined as Global Histologic Disease Activity Score ≤4.

RESULTS

Of 56 included patients, 17 (30%) of 56 showed clinical response, 16 (30%) of 53 showed biochemical response, and 20 (36%) of 56 showed endoscopic response. UST, but not IL-23, concentration in biopsies was correlated to levels in corresponding sera (P < .0001). No correlation was found between UST tissue levels and treatment response. Patients achieving biochemical response showed significantly higher UST serum levels (3.12 µg/mL vs 1.41 µg/mL; P = .01). Tissue IL-23-to-UST ratio correlated with mucosal inflammation (P = .01).

CONCLUSIONS

This is the first study to demonstrate a correlation between serum and tissue UST levels. While tissue IL-23-to-UST ratio correlated with mucosal inflammation, UST serum levels were more indicative for biochemical response. The role of UST levels for therapeutic drug monitoring in inflammatory bowel disease needs further research.

STAT1-mediated induction of Ly6c-expressing macrophages are involved in the pathogenesis of an acute colitis model

BACKGROUND

The development of inflammatory bowel diseases is thought to be multifactorial, but the exact steps in pathogenesis are poorly understood. In this study, we investigated involvement of the activation of STAT1 signal pathway in the pathogenesis of an acute colitis model.

METHODS

A dextran sulfate sodium-induced acute colitis model was established by using wild-type C57BL/6 mice and STAT1-deficient mice. Disease indicators such as body weight loss and clinical score, induction of cytokines, chemokines, and inflammatory cells were evaluated in the acute colitis model.

RESULTS

Disease state was significantly improved in the acute colitis model using STAT1-deficient mice compared with wild-type mice. The induction of Ly6c-highly expressing cells in colorectal tissues was attenuated in STAT1-deficient mice. IL-6, CCL2, and CCR2 gene expressions in Ly6c-highly expressing cells accumulated in the inflamed colon tissues and were significantly higher than in Ly6c-intermediate-expressing cells, whereas TNF-α and IFN-α/β gene expression was higher in Ly6c-intermediate-expressing cells. Blockade of CCR2-mediated signaling significantly reduced the disease state in the acute colitis model.

CONCLUSIONS

Two different types of Ly6c-expressing macrophages are induced in the inflamed tissues through the IFN-α/β-STAT1-mediated CCL2/CCR2 cascade and this is associated with the pathogenesis such as onset, exacerbation, and subsequent chronicity of acute colitis.