The role of Th17 cells in inflammatory bowel disease and the research progress

Gut microbiome shifts in adolescents after sleeve gastrectomy with increased oral-associated taxa and pro-inflammatory potential

Bariatric surgery is highly effective in achieving weight loss in children and adolescents with severe obesity, however the underlying mechanisms are incompletely understood, and gut microbiome changes are unknown. Here, we show that adolescents exhibit significant gut microbiome and metabolome shifts several months after laparoscopic vertical sleeve gastrectomy (VSG), with increased alpha diversity and notably with enrichment of oral-associated taxa. To assess causality of the microbiome/metabolome changes in phenotype, pre-VSG and post-VSG stool was transplanted into germ-free mice. Post-VSG stool was not associated with any beneficial outcomes such as adiposity reduction compared pre-VSG stool. However, post-VSG stool exhibited a potentially inflammatory phenotype with increased intestinal Th17 and decreased regulatory T cells. Concomitantly, we found elevated fecal calprotectin and an enrichment of proinflammatory pathways in a subset of adolescents post-VSG. We show that in some adolescents, microbiome changes post-VSG may have inflammatory potential, which may be of importance considering the increased incidence of inflammatory bowel disease post-VSG.

The interrelationship between intestinal immune cells and enteric α-synuclein in the progression of Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disorder primarily characterized by motor impairment, resulting from the accumulation of α-synuclein and neuronal cell death in the substantia nigra of the midbrain. Emerging evidence suggests that α-synuclein aggregation may originate in the enteric nervous system (ENS) and subsequently propagate to the brain via the vagus nerve. Clinical observations, such as prodromal gastrointestinal dysfunction in PD patients and the increased incidence of PD among individuals with inflammatory bowel disease, support the hypothesis that abnormal intestinal inflammation may contribute to the onset of motor dysfunction and neuropathology in PD. This review examines recent findings on the interplay between intestinal immune cells and α-synuclein aggregation within the framework of gut-originated PD pathogenesis. It begins by discussing evidence linking dysbiosis and intestinal inflammation to α-synuclein aggregation in the ENS. Additionally, it explores the potential role of intestinal immune cells in influencing enteric neurons and α-synuclein aggregation, furthering the understanding of PD development.

Tofacitinib downregulates JAK1 and JAK3 on human intestinal monocytes and macrophages without affecting dendritic cells phenotype or function

Background

Ulcerative colitis (UC) is an inflammatory disorder of the gastrointestinal tract. Although Tofacitinib, which inhibits the JAK1 and JAK3 signalling pathway, is approved to treat patients with UC, its specific mechanism of action remain elusive. Given the central role that conventional dendritic cells (cDC) elicit in gut homeostasis, we hypothesised that Tofacitinib acts modulating cDC function in UC.

Methods

Human biopsies were obtained from colon of controls, and patients with UC (active and quiescent). Lamina propria mononuclear cells (LPMC) were ex-vivo cultured in the presence/absence of Tofacitinib. The specific effect elicited over human intestinal cDC, monocytes and macrophages was assessed by flow cytometry. cDC were also enriched following Tofacitinib conditioning in order to assess its effect over naïve T-cells.

Results

Several human intestinal cDC, monocyte and macrophage subsets can be found in the human colon, with these cells being more similar between controls and patients with qUC referred to patients with aUC. Following ex-vivo culture, Tofacitinib downregulated JAK1 expression on intestinal monocytes from patients with both active and quiescent UC. As for macrophages, JAK1 was decreased on patients with active UC while JAK was downregulated on macrophages from patients with quiescent disease. Tofacitinib did not modulate the phenotype or function of human intestinal cDC.

Conclussion

Tofacitinib does not modulate the phenotype and function of human intestinal cDC in UC. On the contrary, it displays a differential capacity to modulate intestinal monocyte and macrophage phenotype. Future studies should address whether it also translates into a differential function of these cells.

Probiotics: a promising future in the treatment of ulcerative colitis?

Ulcerative colitis is an idiopathic and chronic inflammatory bowel disease, characterized by inflammation of the mucosa of the colon and rectum. Clinical manifestations commonly include abdominal pain, diarrhea (with or without hematochezia), and weight loss. The pathogenesis of ulcerative colitis is multifactorial, involving a combination of genetic predispositions and lifestyle factors. High consumption of processed food, sedentary habits, alcohol intake, and stress are among the lifestyle factors implicated in disease onset and progression. Current treatment strategies focus on managing symptoms and inducing remission, however, the chronic nature of the disease, along with the adverse effects of conventional therapies, often compromises patient's quality of life. Therefore, exploring alternative therapies that can prolong remission and reduce symptom burden is important. Experimental evidence suggests that probiotics may extend remission duration in ulcerative colitis. Moreover, probiotics exhibit efficacy in amelioration clinical symptoms by reducing inflammation markers, preserving, and restoring intestinal epithelial. This review explores the advantages of the administration of probiotics in the treatment of ulcerative colitis, elucidating their mechanism of action.

Integrating Proteomics and GWAS to Identify Key Tissues and Genes Underlying Human Complex Diseases

BACKGROUND

The tissues of origin and molecular mechanisms underlying human complex diseases remain incompletely understood. Previous studies have leveraged transcriptomic data to interpret genome-wide association studies (GWASs) for identifying disease-relevant tissues and fine-mapping causal genes. However, according to the central dogma, proteins more directly reflect cellular molecular activities than RNA. Therefore, in this study, we integrated proteomic data with GWAS to identify disease-associated tissues and genes.

METHODS

We compiled proteomic and paired transcriptomic data for 12,229 genes across 32 human tissues from the GTEx project. Using three tissue inference approaches-S-LDSC, MAGMA, and DESE-we analyzed GWAS data for six representative complex diseases (bipolar disorder, schizophrenia, coronary artery disease, Crohn's disease, rheumatoid arthritis, and type 2 diabetes), with an average sample size of 260 K. We systematically compared disease-associated tissues and genes identified using proteomic versus transcriptomic data.

RESULTS

Tissue-specific protein abundance showed a moderate correlation with RNA expression (mean correlation coefficient = 0.46, 95% CI: 0.42-0.49). Proteomic data accurately identified disease-relevant tissues, such as the association between brain regions and schizophrenia and between coronary arteries and coronary artery disease. Compared to GWAS-based gene association estimates alone, incorporating proteomic data significantly improved gene association detection (AUC difference test, p = 0.0028). Furthermore, proteomic data revealed unique disease-associated genes that were not identified using transcriptomic data, such as the association between bipolar disorder and CREB1.

CONCLUSIONS

Integrating proteomic data enables accurate identification of disease-associated tissues and provides irreplaceable advantages in fine-mapping genes for complex diseases.

Jacalin Attenuates Colitis-Associated Colorectal Carcinogenesis by Inhibiting Tumor Cell Proliferation and Intestinal Inflammation

BACKGROUND

Colorectal cancer (CRC) remains a significant cause of morbidity and mortality worldwide. In patients with inflammatory bowel disease, who have twice the risk of developing CRC, chronic inflammation has been recognized to contribute to colitis-associated cancer (CAC) development. Jacalin, a lectin extracted from jackfruit seeds, has been shown to recognize altered glycosylation and to exert antiproliferative and cytotoxic effects in CRC. However, its activity in CAC remains unknown. Herein, we sought to investigate the effects of jacalin in CAC progression using the dextran sulfate sodium (DSS) and azoxymethane (AOM) mouse model.

METHODS

Colitis-associated cancer induction was performed in male C57BL/6 mice by an intraperitoneal injection of AOM, followed by 3 cycles of 2.5% DSS diluted in drinking water for 7 days, intercalated by 2 weeks of normal drinking water. After 1 week of daily pretreatment, mice were orally treated with phosphate-buffered saline (control group), 100 or 500 µg of jacalin three times a week for an additional 11 weeks.

RESULTS

We showed that jacalin-treated mice presented tumors with reduced volumes and mean size compared to the control group. In addition, both doses of jacalin reduced the number of proliferating cells (Ki-67 positive cells) in tumor tissues, while the higher dose (500 µg) showed also a similar effect in "normal-appearing" colonic crypts. Jacalin treatment attenuated the clinical scores of inflammations, which was accompanied by a reduction of intestinal and/or tumoral production of IL-1β, IL-23, and IL-17.

CONCLUSIONS

Collectively, our findings demonstrated that jacalin suppresses CAC development, highlighting its anti-inflammatory and antitumoral role in the AOM/DSS-induced model.

Transfer of bone marrow niche-residential regulatory T cells ameliorates experimental colitis

BACKGROUND

Adoptive transfer of regulatory T cells (Tregs) has been proposed as a next-generation treatment approach for the treatment of various inflammatory or autoimmune disorders(Amini et al., 2022; Bluestone et al., 2023, 2015; Dall'Era et al., 2019; Chandran et al., 2017; Laukova and Glatman Zaretsky, 2023; Voskens et al., 2023; Canavan et al., 20161-8), inclusive of inflammatory bowel diseases (IBD). Identification of the appropriate Treg populations as donor sources for effective cell therapy is of great importance. We have recently identified specialized Tregs that localize within the hematopoietic stem cell (HSC) microenvironments(Fujisaki et al., 2011; Hirata et al., 2018, 2019, 2015; Kakiuchi et al., 2021a, 2021b; Furuhashi et al., 20259-16) of bone marrow (BM), termed HSC niches. These BM niche Tregs exhibit robust anti-inflammatory and pro-regenerative effects and render HSCs immune privileged. The transfer of BM niche Tregs exhibits high therapeutic effects against BM transplantation and injury(Hirata et al., 2018; Kakiuchi et al., 2021b10, 14). Yet, the treatment effects of transferred BM niche Tregs in non-BM disease settings remain unknown.

OBJECTIVES

We investigated the therapeutic effects of transfer of BM niche Tregs for IBD using mouse models of experimental colitis. To identify the key effector molecule of niche Tregs, we further examined the roles of cell-surface ectoenzyme CD39 expressed at high levels by BM niche Tregs.

STUDY DESIGN

Mouse colitis was induced by administering dextran sulfate sodium salt. Subsequently, the mice received intravenous injections of BM niche Tregs, BM non-niche Tregs, lymph node Tregs, or vehicle alone. We compared these treatment effects on clinical scores, histopathological features and profiles of immune cells. We also tested how targeted deletion of CD39 in the adoptively transferred Tregs impacted experimental outcomes.

RESULTS

The transfer of as few as 1.5 × 104 BM niche Tregs per mouse ameliorated clinical and histopathological features of the mouse colitis far better than the transfer of other Tregs. The transfer of BM niche Tregs inhibited the generation of Th17 cells and promoted the regeneration and recovery of the colon tissue. Targeted deletion of CD39 in Tregs abrogated therapeutic effects of transferred BM niche Tregs.

CONCLUSION

We show robust therapeutic effects of the transfer of BM niche Tregs in the experimental model of colitis. Donor niche Tregs mediate anti-inflammatory and pro-regenerative effects via Treg CD39. Our work suggests the transfer of BM niche Tregs is a promising approach to treat colitic disorders and boost tissue regeneration.

Therapeutic activation of IL-22-producing innate lymphoid cells enhances host defenses to Clostridioides difficile infection

Clostridioides difficile causes debilitating colitis via secreted toxins that disrupt the intestinal barrier, and toxemia is associated with severe disease. Thus, therapies that fortify the intestinal barrier will reduce the severity of infection. Innate lymphoid cells (ILCs) are critical in the defense against acute C. difficile infection and represent a promising therapeutic target to limit disease. Here, we report that oral administration of the Toll-like receptor (TLR) 7 agonist R848 limits intestinal damage and protects mice from lethal C. difficile infection without impacting pathogen burden or altering the intestinal microbiome. R848 induced interleukin (IL)-22 secretion by ILCs, leading to STAT3 phosphorylation in the intestinal epithelium and increased stem cell proliferation. Genetic ablation of ILCs, IL-22, or epithelial-specific STAT3 abrogated R848-mediated protection. R848 reduced intestinal permeability following infection and limited systemic toxin dissemination. Combined, these data identify an immunostimulatory molecule that activates IL-22 production in ILCs to enhance host tissue defenses following C. difficile infection.

Spontaneous Generation of an Endogenous RORγt Agonist

The transcription factor RORγt regulates the development of Th17 cells and their inflammatory cytokine IL-17─a pathway that can both clear bacterial pathogens and drive autoimmune diseases. An endogenous RORγt agonist with a noncanonical structure, a lysophosphatidylethanolamine (1-18:1-LPE or 1), was recently identified, and its identity both increases our understanding of immune regulation and creates options for therapeutic intervention. Compound 1 could be formed directly through enzymatic cleavage of a suitable phosphatidylethanolamine (PE) by a phospholipase A2 (PLA2) or by "triggering" of a suitable plasmalogen with accompanying 1,2-acyl migration from the sn-2 to sn-1 positions of glycerol. This study illustrates the plausibility of a plasmalogen-based pathway through synthesis of the plasmalogen precursor (2) and triggering the plasmalogen's electron-rich vinyl ether with small electrophiles characteristic of inflammatory and tumor environments to create 1-18:1-LPE (1). The plasmalogen-based pathway is consistent with previous studies on the formation of 1, and it also conforms to Lands rules for acyl chain distribution and provides a mechanism for immune signaling with both spatial and temporal control.

Lentinula edodes as a Source of Bioactive Compounds with Therapeutical Potential in Intestinal Inflammation and Colorectal Cancer

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a rising global health issue. Chronic intestinal inflammation is an important risk factor for colorectal cancer (CRC). Despite significant progress in IBD and CRC treatment, numerous patients remain resistant to standard pharmacotherapy or experience severe side effects that prevent them from continuing treatment. There is evidence suggesting that bioactive substances in Lentinula edodes have immunomodulatory and anticancer properties. This fungus is currently classified as a functional food, considering its beneficial effects on human health and special nutritional value. Studies conducted in vitro and in animal models demonstrated that L. edodes bioactive compounds, in particular glucans, have anti-inflammatory and antioxidant effects, induce apoptosis of cancer cells, reduce tumor angiogenesis, restore gut microbiome heterogeneity and improve gut barrier dysfunction. Moreover, clinical trials confirmed that these compounds combined with standard chemotherapy have a significant effect in improving the prognosis of CRC patients. In addition, L. edodes glucans increase microbial diversity and enhance interferon (IFN)-γ production by immune cells. Future studies must be focused on understanding the pathways and mechanisms associated with the observed effects. Moreover, both randomized trials and long-term follow-up studies are needed to confirm their effectiveness in the treatment of IBD and CRC.

Ketogenic diet and cancer: multidimensional exploration and research

The ketogenic diet (KD) has attracted attention in recent years for its potential anticancer effects. KD is a dietary structure of high fat, moderate protein, and extremely low carbohydrate content. Originally introduced as a treatment for epilepsy, KD has been widely applied in weight loss programs and the management of metabolic diseases. Previous studies have shown that KD can potentially inhibit the growth and spread of cancer by limiting energy supply to tumor cells, thereby inhibiting tumor angiogenesis, reducing oxidative stress in normal cells, and affecting cancer cell signaling and other processes. Moreover, KD has been shown to influence T-cell-mediated immune responses and inflammation by modulating the gut microbiota, enhance the efficacy of standard cancer treatments, and mitigate the complications of chemotherapy. However, controversies and uncertainties remain regarding the specific mechanisms and clinical effects of KD as an adjunctive therapy for cancer. Therefore, this review summarizes the existing research and explores the intricate relationships between KD and cancer treatment.

Modulation of occludin, NF-κB, p-STAT3, and Th17 response by DJ-X-025 decreases inflammation and ameliorates experimental colitis

SCOPE

Inflammatory bowel disease (IBD) involves a range of immune-mediated disorders marked by systemic and local intestinal inflammation. We synthesized a novel compound DJ-X-025 and uncovered its anti-inflammatory properties using lipopolysaccharide (LPS)-induced RAW 264.7 macrophages in vitro and a dextran sodium sulfate (DSS)-induced model of colitis.

METHODS AND RESULTS

We evaluated the alteration in cell morphology, cytoskeletal proteins, and inflammatory markers of DJ-X-025 treated LPS-stimulated RAW 264.7 macrophages. We administered DJ-X-025 by oral gavage in DSS-induced colitis, examined colon histology, and alterations of immune cells by flow cytometry, and performed molecular studies using RT-qPCR and western blot analysis. DJ-X-025 treatment markedly altered the morphology of LPS-treated RAW 264.7 macrophages from elongated to round shapes, modulated actin and tubulin, and reduced the level of inflammatory markers like TNF-α, IL-1β, IL-6, and iNOS. Further, we observed that DJ-X-025 steered to improve colon length, muscularis mucosa thickness, and colon inflammatory score compared to the DSS group alone. DJ-X-025 effectively inverted the increased population of activated T cells, Th17, and macrophages in lamina propria by DSS treatment, leading to a substantial reduction in the inflammatory response in the colon. Strikingly, DJ-X-025 treatment enhanced the expression of occludin and diminished the expression of NF-κB and phosphorylation of STAT3 in the colon of DSS-treated mice compared to DSS-alone. Additionally, DJ-X-025 induced the expression of Foxp3 in the colon and, reduced systemic inflammatory cytokine/chemokine levels further supporting its immunomodulatory effects. These results suggest that DJ-X-025 is linked to the induction of occludin expression and decreased expression of p-STAT3/NF-κB and Th17 response in the colon, which together suppresses systemic and colon inflammatory cytokines for effective amelioration of experimental colitis.

CONCLUSION

These findings suggest that DJ-X-025 might be a promising therapeutic agent for the treatment of IBD.

The Role of IL-17A in Mediating Inflammatory Responses and Progression of Neurodegenerative Diseases

IL-17A has been implicated as a critical pro-inflammatory cytokine in the pathogenesis of autoimmune and neurodegenerative disorders. Emerging evidence indicates its capacity to activate microglial cells and astrocytes, subsequently inducing the production of inflammatory mediators that exacerbate neuronal injury and functional impairment. Clinical observations have revealed a demonstrated association between IL-17A concentrations and blood-brain barrier (BBB) dysfunction, creating a pathological feedback loop that amplifies neuro-inflammatory responses. Recent advances highlight the cytokine's critical involvement in neurodegenerative disorders through multiple molecular pathways. Therapeutic interventions utilizing monoclonal antibodies (mAbs) against IL-17A or its cognate receptor (IL-17R) have shown promising clinical potential. This review systematically examines the IL-17A-mediated neuro-inflammatory cascades; the mechanistic contributions to neurodegenerative pathology in the established disease models including multiple sclerosis, Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis; and current therapeutic strategies targeting the IL-17A signaling pathways. The analysis provides novel perspectives on optimizing cytokine-directed therapies while identifying the key challenges and research priorities for translational applications in neurodegeneration.

CGRPβ suppresses the pathogenesis of ulcerative colitis via the immunoproteasome

Various factors have been implicated in the pathogenesis of ulcerative colitis (UC), with immune system failure being the most important one. Calcitonin gene-related peptide (CGRP), a neuropeptide with two isoforms, CGRPα and CGRPβ, has been reported to regulate the immune system. In this study, we investigated the role of CGRP isoforms in UC pathogenesis. We induced UC-like symptoms in CGRPα and CGRPβ knockout (KO) mice using dextran sulphate sodium. Compared to wild-type and CGRPα KO mice, CGRPβ-deficient mice exhibited severe symptoms with increased blood in the stool and diarrhoea. Proteome analysis revealed significant up-regulation of immune-related proteins and immunoproteasome components in CGRPβ-deficient mice, suggesting that an enhanced immune response contributes to the severity of this disease. Treatment with ONX-0914, an immunoproteasome inhibitor, markedly improved these symptoms, highlighting the role of the immunoproteasome in exacerbating UC. This study provides the first evidence that CGRPβ protects against UC by modulating immune responses, particularly those mediated by the immunoproteasome. Our findings suggest that functional differences in CGRP isoforms may influence the severity and management of UC. This insight into the neuro-immune mechanism of UC opens avenues for novel therapies that address both the neural and immune aspects of this disease.

A review of gut failure as a cause and consequence of critical illness

In critical illness, all elements of gut function are perturbed. Dysbiosis develops as the gut microbial community loses taxonomic diversity and new virulence factors appear. Intestinal permeability increases, allowing for translocation of bacteria and/or bacterial products. Epithelial function is altered at a cellular level and homeostasis of the epithelial monolayer is compromised by increased intestinal epithelial cell death and decreased proliferation. Gut immunity is impaired with simultaneous activation of maladaptive pro- and anti-inflammatory signals leading to both tissue damage and susceptibility to infections. Additionally, splanchnic vasoconstriction leads to decreased blood flow with local ischemic changes. Together, these interrelated elements of gastrointestinal dysfunction drive and then perpetuate multi-organ dysfunction syndrome. Despite the clear importance of maintaining gut homeostasis, there are very few reliable measures of gut function in critical illness. Further, while multiple therapeutic strategies have been proposed, most have not been shown to conclusively demonstrate benefit, and care is still largely supportive. The key role of the gut in critical illness was the subject of the tenth Perioperative Quality Initiative meeting, a conference to summarize the current state of the literature and identify key knowledge gaps for future study. This review is the product of that conference.

Histone deacetylase in inflammatory bowel disease: novel insights

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is characterized by chronic nonspecific intestinal inflammation. Despite considerable efforts, IBD remains a heavy burden on society and human health, with increasing morbidity. Posttranslational modification, especially histone acetylation, is a key process in controlling DNA transcriptional activity. Histone deacetylases (HDACs) play a vital role in the mechanism of IBD pathogenesis through histone and nonhistone protein deacetylation. Herein, we present a summary of different categories of HDACs as well as HDAC inhibitors (HDACis) and analyze the role of HDAC inhibition in alleviating IBD along with its mechanism, as well as clinical potential of HDACis in IBD treatment.

(Poly)phenols and Multiple Sclerosis: Results from an Observational Cross-Sectional Study

(Poly)phenols are a wide and heterogeneous class of substances with several potential health benefits. Their role in neuroprotection and cognition is still questionable. This study's scope is to examine the possible association between total and individual (poly)phenol intake, major dietary sources, and the severity of multiple sclerosis (MS) in a cohort of MS patients. Participants' demographics, physical activity, smoking, and dietary information were collected, alongside clinical parameters including the Expanded Disability Status Score (EDSS), Multiple Sclerosis Severity Score (MSSS), MS phenotype, and current therapy. A validated 110-item food frequency questionnaire (FFQ) was used to assess participants' habits. The (poly)phenol content of foods was estimated using the Phenol-Explorer database. Data from 106 participants were analyzed. A high intake of vegetables was associated with a 4.6-fold higher probability of mild MS (95% CI: 1.49, 14.28), whereas no association was found for other food and beverage sources. Hydroxycinnamic acids were significantly related to MSSS (OR: 6.55, 95% CI: 2.15, 19.92). Although coffee intake differed significantly between patients with mild and severe MS (90.5 ± 53.9 vs. 59.4 ± 40.8 mL/d, respectively), linear regression analysis did not confirm an association with MSSS. A higher intake of hydroxycinnamic acids and vegetables may impact MS severity. Coffee's role remains unclear and needs to be further investigated.

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

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

Targeting gut microbiota to regulate the adaptive immune response in atherosclerosis

Atherosclerosis, the leading cause of death worldwide, is a chronic inflammatory disease leading to the accumulation of lipid-rich plaques in the intima of large and medium-sized arteries. Accumulating evidence indicates the important regulatory role of the adaptive immune system in atherosclerosis during all stages of the disease. The gut microbiome has also become a key regulator of atherosclerosis and immunomodulation. Whilst existing research extensively explores the impact of the microbiome on the innate immune system, only a handful of studies have explored the regulatory capacity of the microbiome on the adaptive immune system to modulate atherogenesis. Building on these concepts and the pitfalls on the gut microbiota and adaptive immune response interaction, this review explores potential strategies to therapeutically target the microbiome, including the use of prebiotics and vaccinations, which could influence the adaptive immune response and consequently plaque composition and development.

Dietary Inflammatory Score (DIS)'s and Lifestyle Inflammatory Score (LIS)'s Impact on Multiple Sclerosis Severity

Background/Objectives: Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system with variable degrees of inflammation and gliosis. Diet and lifestyle factors could influence MS development and also contribute to inflammation. The current study aims to evaluate the relationship between dietary and lifestyle inflammatory potential and multiple sclerosis severity. Methods: A cross-sectional study design was employed. Data collection included demographic, neurological, and nutritional information. The Dietary Inflammatory Score (DIS) and Lifestyle Inflammatory Score (LIS) were calculated based on the reference protocol. Results: One hundred and seven participants (69.2% female; mean age, 50.6 ± 11.6 years) completed the study. The anti-inflammatory LIS group had significantly higher proportions of normal-weight (p = 0.000) and physically active (p = 0.022) participants. A greater proportion of women exhibited an anti-inflammatory lifestyle compared to men (80% vs. 20%; p = 0.023). No relation was retrieved between the DIS, LIS, and MS Severity Score (MSSS). When analyzing the single DIS components, leafy greens were associated with MS severity (OR 1.67; 95% CI, 1.50-18.74; p = 0.009). Among the LIS components, "high physical activity" (OR 5.51; 95% CI, 1.66-18.30; p = 0.005) and "heavy drinking" (OR 5.61; 95% CI, 1.19-26.47; p = 0.029) were related to lower MS severity. Conclusions: Although no differences were found in the total Dietary and Lifestyle Inflammatory Scores, some of their components might be connected with MS severity. Further intervention studies are needed to validate these findings.

Vaccines for cancer interception in familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is an inherited autosomal dominant disorder caused by germline mutations in the adenomatous polyposis coli (APC) gene. FAP is associated with the development of hundreds of adenomas in the small and large intestines of individuals starting in the teenage years with a near 100% risk of developing colorectal cancer by adulthood. Eventually polyps develop throughout the gastrointestinal tract. Chemoprevention approaches have been somewhat successful in reducing polyp burden, but have not reduced the risk of the development of colorectal cancer or other cancers. The lack of efficacy of more standard drug approaches may be due to limited exposure to the agent only to specific periods while the drug is being metabolized, limited drug penetrance in the colon, and patient adherence to daily dosing and drug side effects. The success of immune therapy for the treatment of invasive cancer has led to research focused on the use of immune based approaches for polyp control in FAP, specifically polyp directed vaccines. Vaccines targeting antigens expressed in FAP lesions may be a superior method to control polyp burden and prevent disease progression as compared to classic chemoprevention drugs. A limited number of vaccines can be administered over a short period of time to generate a lasting immune response. Appropriately primed antigen specific T-cells can traffic to any site in the body where antigen is expressed, recognize, and eliminate the antigen expressing cell. Immunologic memory will allow the immune response to persist and the specificity of the immune response will limit toxicity to the targeted polyp. This review will examine the current state of vaccines directed against FAP lesions and highlight the challenges and opportunities of translating vaccines for cancer interception in FAP to the clinic.

Placebo-Controlled Trials in the Management of Crohn's Disease: An Umbrella Review of Meta-Analyses

INTRODUCTION

Crohn's disease is a chronic inflammatory bowel disease characterized by abdominal pain, diarrhea, and other symptoms. It can lead to significant complications and impact patients' quality of life. Therefore, effective management strategies are essential for improving outcomes.

METHODS

To assess the efficacy of the treatments for Crohn's disease, this umbrella review systematically addresses systematic reviews and meta-analyses on Crohn's disease management published between 2013 and 2023. The quality of the included studies was assessed using the National Institutes of Health's quality assessment tool.

RESULTS

Sixteen studies were included, evaluating various interventions for the induction and maintenance of remission. These included biologic agents (anti-TNF agents, anti-IL-12/23p40 antibodies, and integrin receptor antagonists), antimetabolites, and corticosteroids.

CONCLUSIONS

The findings suggest that biologic agents may be promising options for both the induction and maintenance of remission in Crohn's disease. Antimetabolites and corticosteroids may be effective in certain cases, but their efficacy and safety profiles require further investigation. The included studies varied in quality and sample size. More research is needed to confirm the findings and establish optimal treatment strategies. Moreover, while biologic agents show promise, the optimal management of Crohn's disease requires further research. A personalized approach considering patient factors and disease characteristics is crucial for optimizing outcomes.

Immunometabolism of Tregs: mechanisms, adaptability, and therapeutic implications in diseases

Immunometabolism is an emerging field that explores the intricate interplay between immune cells and metabolism. Regulatory T cells (Tregs), which maintain immune homeostasis in immunometabolism, play crucial regulatory roles. The activation, differentiation, and function of Tregs are influenced by various metabolic pathways, such as the Mammalian targets of rapamycin (mTOR) pathway and glycolysis. Correspondingly, activated Tregs can reciprocally impact these metabolic pathways. Tregs also possess robust adaptive capabilities, thus enabling them to adapt to various microenvironments, including the tumor microenvironment (TME). The complex mechanisms of Tregs in metabolic diseases are intriguing, particularly in conditions like MASLD, where Tregs are significantly upregulated and contribute to fibrosis, while in diabetes, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA), they show downregulation and reduced anti-inflammatory capacity. These phenomena suggest that the differentiation and function of Tregs are influenced by the metabolic environment, and imbalances in either can lead to the development of metabolic diseases. Thus, moderate differentiation and inhibitory capacity of Tregs are critical for maintaining immune system balance. Given the unique immunoregulatory abilities of Tregs, the development of targeted therapeutic drugs may position them as novel targets in immunotherapy. This could contribute to restoring immune system balance, resolving metabolic dysregulation, and fostering innovation and progress in immunotherapy.

Intestinal tissue levels of anti-TNF alpha, antibodies, and cytokines in paediatric Crohn disease

The aim was to explore factors associated with intestinal tissue levels of anti-TNF alpha (anti-TNF), anti-TNF antibodies, and cytokines in pediatric patients with Crohn Disease (CD). In a prospective exploratory study of CD patients undergoing ileocecal resection or colonoscopy between 6/2020 and 1/2023, we analysed tissue levels of anti-TNF, anti-TNF antibodies, and cytokines (TNF-α, IL-17, IL-1β, IFN-γ) from intestinal biopsies. Mixed-effects regression models, adjusted for potential confounders, were used. Data from 27 CD patients (18 females, 66.7%) were analysed. Fourteen (52%) received adalimumab (ADA) and thirteen received infliximab (IFX), with a median therapy duration of 17 (IQR 4.5-41.5) months. Higher levels of free anti-TNF were found in macroscopically inflamed tissue compared to non-inflamed tissue (β = 3.42, 95% CI 1.05-6.10). No significant association was found between serum and tissue anti-TNF levels (β= -0.06, 95% CI - 0.70-0.58). Patients treated longer with anti-TNF had increased IL-17 levels (β = 0.19, 95% CI 0.05-0.33), independent of disease duration and age. IFN-γ levels were linked with both follow-up duration and anti-TNF length. Our study shows significantly higher free drug levels in inflamed tissue. Long-term anti-TNF treatment has been linked to increased IL-17 levels, suggesting a possible impact on the cytokine response pathway. We did not observe a relationship between serum and tissue anti-TNF levels.

SHIP-1 regulates the differentiation and function of Tregs via inhibiting mTORC1 activity

Cell metabolism is crucial for orchestrating the differentiation and function of regulatory T cells (Tregs). However, the underlying mechanism that coordinates cell metabolism to regulate Treg activity is not completely understood. As a pivotal molecule in lipid metabolism, the role of SHIP-1 in Tregs remains unknown. In this study, we found SHIP-1 Treg KO mice (SHIP-1 specifically deleted in regulatory T cells) had severe autoimmunity with increased Tregs in the thymus and disrupted peripheral T cell homeostasis. Mechanistically, CD4Cre Ship-1flox/flox mice were found to have increased Treg precursors and SHIP-1 KO Tregs had reduced migration and stability, which caused decreased Tregs in the spleen. Additionally, the suppressive function of Tregs from SHIP-1 KO mice was diminished, along with their promotion of anti-tumor immunity. Interestingly, the PI3K-mTORC1, but not mTORC2, signaling axis was enhanced in SHIP-1 KO Tregs. In vivo treatment of SHIP-1 Treg KO mice with rapamycin rescued the abnormal Treg percentages and peripheral T cell homeostasis, as well as Treg suppressive function. Furthermore, the treatment of wild-type mice with SHIP-1 inhibitor enhanced anti-tumor activity. Our study highlights the SHIP-1-PI3K-mTORC1 axis that regulates Treg differentiation and function, and it is a potential target for cancer treatment.

Pyroptosis the Emerging Link Between Gut Microbiota and Multiple Sclerosis

This review elucidates the pivotal role of pyroptosis, triggered by gut microbiota, in the development of multiple sclerosis (MS), emphasizing its significance within the gut-brain axis. Our comprehensive analysis of recent literature reveals how dysbiosis in the gut microbiota of MS patients-characterized by reduced microbial diversity and shifts in bacterial populations-profoundly impacts immune regulation and the integrity of the central nervous system (CNS). Pyroptosis, an inflammatory form of programmed cell death, significantly exacerbates MS by promoting the release of inflammatory cytokines and causing substantial damage to CNS tissues. The gut microbiota facilitates this detrimental process through metabolites such as short-chain fatty acids and neuroactive compounds, or self-structural products like lipopolysaccharides (LPS), which modulate immune responses and influence neuronal survival. This review highlights the potential of modulating gut microbiota to regulate pyroptosis, thereby suggesting that targeting this pathway could be a promising therapeutic strategy to mitigate inflammatory responses and preserve neuronal integrity in patients with MS.

A pectic polysaccharide from Lycium ruthenicum Murray alleviates dextran sulfate sodium-induced colitis in mice

Inflammatory bowel disorders (IBD) can lead to severe complications like perforation, bleeding, and colon cancer, posing life-threatening risks. Lycium ruthenicum Murray (L. ruthenicum Murr.), rich in polysaccharides, has been utilized in traditional diets for thousands of years. This study explores the protective effects of the polysaccharide of L. ruthenicum on mice with dextran sulfate sodium (DSS)-induced colitis. In the present study, a pectic polysaccharide (LRWP-Ap) containing arabinogalactan (AG) and homogalacturonic acid (HG) structural domains with a Mw of 4.34 kDa was obtained from L. ruthenicum Murr. Fruit. The gavage administration of LRWP-Ap significantly alleviated symptoms of DSS-induced colitis in mice. In this process, LRWP-Ap modulated the balance of Arg-1/iNOS to regulate the metabolism of arginine, and the levels of intestinal tight junction (TJ) (ZO-1, Occludin, and Claudin 1) were increased by LRWP-Ap treatment, which promoted intestinal barrier function. In addition, LRWP-Ap alleviated the inflammatory response while increasing the anti-inflammatory response by reducing the level of proinflammatory factors, enhancing the level of anti-inflammatory factors (IL-10) and improving the balance of Treg/Th17 cells. These effects resulted in the maintenance of intestinal immune homeostasis. Moreover, LRWP-Ap modulated the gut microbiota composition and short-chain fatty acid (SCFA) content, which may maintain relatively favorable intestinal homeostasis. In general, LRWP-Ap has the potential to alleviate IBD, and the use of L. ruthenicum Murr. As a natural functional food to improve gut health in the context of DSS-induced colitis.

Roles of hypoxia-inducible factor-prolyl hydroxylases in aging and disease

The prolyl hydroxylase domain-containing (PHD or EGL9-homologs) enzyme family is mainly known for its role in the cellular response to hypoxia. HIF-PH inhibitors can stabilize hypoxia-inducible factors (HIFs), activating transcriptional programs that promote processes such as angiogenesis and erythropoiesis to adapt to changes in oxygen levels. HIF-PH inhibitors have been clinically approved for treating several types of anaemia. While most discussions of the HIF-PH signalling axis focus on hypoxia, there is a growing recognition of its importance under normoxic conditions. Recent advances in PHD biology have highlighted the potential of targeting this pathway therapeutically for a range of aging-related diseases. In this article, we review these recent discoveries, situate them within the broader context of aging and disease, and explore current therapeutic strategies that target PHD enzymes for these indications.

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

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

Beyond Suppression: Peripheral T Cell Responses to Vaccination in Inflammatory Bowel Disease Patients Undergoing Anti-Tumor-Necrosis-Factor Therapy

Alimentary tract inflammation in inflammatory bowel disease (IBD) is treated by systemically administered drugs that alter fundamental host immune responses. Biologics that target tumor necrosis factor (TNF) are first-line biologics in IBD, used widely for their effectiveness, steroid-sparing quality, and lower cost. While they enable a significant proportion of patients to achieve clinical remission, they carry an increased risk of infection and poor serological responses to vaccination. Conversely, our understanding of adaptive T cell responses in anti-TNF-treated IBD patients remains limited. The introduction of COVID-19 vaccines has prompted research that both challenges and refines our view on immunomodulatory therapy and its potential implications for immunity and protection. Here, we review these emergent findings, evaluate how they shape our understanding of vaccine-induced T cell responses in the context of anti-TNF therapy in IBD, and provide a perspective highlighting the need for a holistic evaluation of both cellular and humoral immunity in this population.

Neutralization of TLR2 in combination with either TNF-α or IL-1β antibody reduces the severity of septic arthritis through STAT3/mTOR signalling in lymphocytes

Staphylococcus aureus induced Septic arthritis is considered a medical concern. S.aureus binds TLR2 to induce an array of inflammatory responses. Generation of pro-inflammatory cytokines induces T cell responses and control Th17/Treg cell balance. Regulation of T cell-mediated immunity in response to inflammation is significantly influenced by mTOR. Presence of elevated TNF-α, IL-1β decreases Treg cell activity through STAT3/mTOR, promoting proliferation of T cells towards Th17 cells. Therefore, we postulated, neutralizing TLR2 with either TNF-α or IL-1β in combination could be useful in modifying Th17/Treg cell ratio in order to treat septic arthritis by suppressing expression of mTOR/STAT3. To date, no studies have reported effects of neutralization of TLR2 along with either TNF-α or IL-1β on amelioration of arthritis correlating with mTOR/STAT3 expression. Contribution of T lymphocytes collected from blood, spleen, synovial tissues, their derived cytokines IFN-γ, IL-6, IL-17, TGF-β, IL-10 were noted. Expression of TLR2, TNFR1, TNFR2, NF-κB along with mTOR/STAT3 also recorded. Neutralization of TLR2 along with TNF-α and IL-1β were able to shift Th17 cells into immunosuppressive Treg cells. Furthermore,elevated expression of IL-10, TNFR2 and demoted expression of mTOR/ STAT3 along with NF-κB in lymphocytes confirms its role in resolution of arthritis. It was also effective in reducing oxidative stress via increasing expression of the antioxidant enzymes. As a result, it can be inferred that Treg-derived IL-10, which may mitigate inflammatory effects of septic arthritis by influencing the mTOR/STAT3 interaction in lymphocytes, may be selected as a different therapeutic strategy for reducing the impact of septic arthritis.

Secretory IgA in breast milk protects against asthma through modulation of the gut microbiota

Asthma susceptibility is linked to dysbiosis in early-life gut microbiota, and the antibody secretory immunoglobulin (Ig)A (SIgA) is a key determinant of gut microbiota composition. SIgA is obtained through breast milk during the critical early-life window. We use a mouse model of SIgA deficiency and the house dust mite (HDM) model of asthma to elucidate the role of maternal SIgA in modulating the early-life gut microbiota and asthma protection. Mice that do not receive maternal SIgA display a transient bloom of segmented filamentous bacteria (SFB) in the small intestine during the early post-weaning period. Mice that do not receive maternal SIgA also display elevated T helper type 17 (Th17) cell activation in the intestine, which persists into adulthood and is associated with more severe inflammation in response to the HDM model of asthma. This study demonstrates a mechanism by which breast-milk-derived SIgA influences immune development and asthma susceptibility by modulating the early-life gut microbiota.

Development of dual GPBAR1 agonist and RORγt inverse agonist for the treatment of inflammatory bowel diseases

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are chronic disorders characterized by dysregulated immune response and persistent inflammation. Recent studies suggest that bile acid receptors, particularly GPBAR1, and the transcription factor RORγt play critical roles in modulating intestinal inflammation. This study evaluates the therapeutic potential of PBT002, a dual GPBAR1 agonist and RORγt inverse agonist, in IBD models. The effects of PBT002 were assessed through in vitro and in vivo experiments. Macrophages and T lymphocytes obtained from the buffy coat were exposed to PBT002 to evaluate its immunomodulatory activity. The beneficial effects in vivo were evaluated in mouse models of colitis induced by TNBS, DSS or DSS + IL-23 using also a Gpbar1 knock-out male mice. PBT002 exhibited an EC50 of 1.2 µM for GPBAR1 and an IC50 of 2.8 µM for RORγt. In in vitro, PBT002 modulated macrophage polarization towards an anti-inflammatory M2 phenotype and reduced Th17 cell markers while increasing Treg markers. In the TNBS-induced colitis model, PBT002 reduced weight loss, CDAI, and colon damage, while it modulated cytokine gene expression towards an anti-inflammatory profile. In GPBAR1-/-, the anti-inflammatory effects of PBT002 were attenuated, indicating partial GPBAR1 dependence. RNA sequencing revealed significant modulation of inflammatory pathways by PBT002. In DSS+IL-23 induced colitis, PBT002 mitigated disease exacerbation, reducing pro-inflammatory cytokine levels and immune cell infiltration. In conclusion, PBT002, a GPBAR1 agonist and RORγt inverse agonist, modulates both the innate and adaptive immune responses to reduce inflammation and disease severity in models of IBD.

Gut microbiome shifts in adolescents after sleeve gastrectomy with increased oral-associated taxa and pro-inflammatory potential

Background

Bariatric surgery is highly effective in achieving weight loss in children and adolescents with severe obesity, however the underlying mechanisms are incompletely understood, and gut microbiome changes are unknown.

Objectives

1) To comprehensively examine gut microbiome and metabolome changes after laparoscopic vertical sleeve gastrectomy (VSG) in adolescents and 2) to assess whether the microbiome/metabolome changes observed with VSG influence phenotype using germ-free murine models.

Design

1) A longitudinal observational study in adolescents undergoing VSG with serial stool samples undergoing shotgun metagenomic microbiome sequencing and metabolomics (polar metabolites, bile acids and short chain fatty acids) and 2) a human-to-mouse fecal transplant study.

Results

We show adolescents exhibit significant gut microbiome and metabolome shifts several months after VSG, with increased alpha diversity and notably with enrichment of oral-associated taxa. To assess causality of the microbiome/metabolome changes in phenotype, pre-VSG and post-VSG stool was transplanted into germ-free mice. Post-VSG stool was not associated with any beneficial outcomes such as adiposity reduction compared pre-VSG stool. However, post-VSG stool exhibited an inflammatory phenotype with increased intestinal Th17 and decreased regulatory T cells. Concomitantly, we found elevated fecal calprotectin and an enrichment of proinflammatory pathways in a subset of adolescents post-VSG.

Conclusion

We show that in some adolescents, microbiome changes post-VSG may have inflammatory potential, which may be of importance considering the increased incidence of inflammatory bowel disease post-VSG.

Umbilical cord mesenchymal stem cells in ulcerative colitis treatment: efficacy and possible mechanisms

BACKGROUND

Mesenchymal stem cells (MSCs) possess powerful immunomodulatory ability. This study aimed to assess the efficacy and safety of human umbilical cord-derived mesenchymal stem cells (UMSCs) in patients with ulcerative colitis (UC) and to explore the potential mechanisms.

METHODS

This prospective, self-controlled clinical study was conducted at Henan Provincial People's Hospital. Patients with moderate-to-severe active UC, unresponsive to traditional drugs were continuously enrolled from September 2018 to March 2023. UMSCs were administered intravenously monthly for two months at a cell dosage of 1 × 106 per kg. The primary outcome was a clinical response at 2 months. The levels of cytokines and progerin in the plasma of the patients were analyzed using enzyme-linked immunosorbent assay kits, and longitudinal data was analyzed using generalized estimation equation.

RESULTS

Forty-one patients were enrolled and received UMSC therapy. At 2 months, 73.2% (30/41) of patients achieved a clinical response, and 41.5% (17/41) achieved a clinical remission. At 6 months, 2 patients were lost to follow-up; the corresponding figures were 70.0% (25/41) and 34.2% (14/41), respectively. After UMSC therapy, the Mayo score, Mayo endoscopy score, mean and maximum values of Ulcerative Colitis Endoscopic Index of Severity and Nancy index were significantly reduced compared with baseline values. Additionally, the levels of progerin and inflammatory markers, such as interleukin (IL)-1β, IL-6, IL-8, IL-12, and IL-17 A decreased, while hemoglobin, albumin, and IL-10/IL-17 A ratio increased, particularly in the response group. Multiple stepwise logistic regression analysis showed age was an independent risk factor affecting efficacy (odds ratio, 0.875 (95% confidence interval (0.787, 0.972)); the area under the receiver operating characteristic curve for age was 0.79. No serious adverse events were observed during or after UMSC therapy.

CONCLUSION

UMSCs are safe and effective for patients with UC, with age being an independent risk factor affecting efficacy. Mechanistically, UMSC treatment may ameliorate cell senescence and suppress the secretion of pro-inflammatory cytokines.

TRIAL REGISTRATION

The study was retrospectively registered at www.chictr.org.cn/ (ChiCTR1900026035) on September 18, 2019.

Microbiome-Mucosal Immunity Nexus: Driving Forces in Respiratory Disease Progression

The importance of the complex interplay between the microbiome and mucosal immunity, particularly within the respiratory tract, has gained significant attention due to its potential implications for the severity and progression of lung diseases. Therefore, this review summarizes the specific interactions through which the respiratory tract-specific microbiome influences mucosal immunity and ultimately impacts respiratory health. Furthermore, we discuss how the microbiome affects mucosal immunity, considering tissue-specific variations, and its capacity in respiratory diseases containing asthma, chronic obstructive pulmonary disease, and lung cancer. Additionally, we investigate the external factors which affect the relationship between respiratory microbiome and mucosal immune responses. By exploring these intricate interactions, this review provides valuable insights into the potential for microbiome-based interventions to modulate mucosal immunity and alleviate the severity of respiratory diseases.

A broken network of susceptibility genes in the monocytes of Crohn's disease patients

Genome-wide association studies have identified over 200 genetic loci associated with inflammatory bowel disease; however, the mechanism of such a large amount of susceptibility genes remains uncertain. In this study, we integrated bioinformatics analysis and two independent single-cell transcriptome datasets to investigate the expression network of 232 susceptibility genes in Crohn's disease (CD) patients and healthy controls. The study revealed that most of the susceptibility genes are specifically and strictly expressed in the monocytes of the human intestinal tract. The susceptibility genes established a network within the monocytes of health control. The robustness of a gene network may prevent disease onset that is influenced by the genetic and environmental alteration in the expression of susceptibility genes. In contrast, we showed a sparse network in pediatric/adult CD patients, suggesting the broken network contributed to the CD etiology. The network status of susceptibility genes at the single-cell level of monocytes provided novel insight into the etiology.

[Old and New Biologics and Small Molecules in Inflammatory Bowel Disease: Anti-interleukins]

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a chronic inflammatory disease of the gastrointestinal tract. The introduction of biologics, particularly anti-interleukin (IL) agents, has revolutionized IBD treatment. This review summarizes the role of ILs in IBD pathophysiology and describes the efficacy and positioning of anti-IL therapies. We discuss the functions of key ILs in IBD and their potential as therapeutic targets. The review then discusses anti-IL therapies, focusing primarily on ustekinumab (anti-IL-12/23), risankizumab (anti-IL-23), and mirikizumab (anti-IL-23). Clinical trial data demonstrate their efficacy in inducing and maintaining remission in Crohn's disease and ulcerative colitis. The safety profiles of these agents are generally favorable. However, long-term safety data for newer agents are still limited. The review also briefly discusses emerging therapies such as guselkumab and brazikumab. Network meta-analyses suggest that anti-IL therapies perform well compared to other biological agents. These agents may be considered first- or second-line therapies for many patients, especially those with comorbidities or safety concerns. Anti-IL therapies represent a significant advancement in IBD treatment, offering effective and relatively safe options for patients with moderate to severe disease.

SUMOylation at the crossroads of gut health: insights into physiology and pathology

SUMOylation, a post-translational modification involving the covalent attachment of small ubiquitin-like modifier (SUMO) proteins to target substrates, plays a pivotal role at the intersection of gut health and disease, influencing various aspects of intestinal physiology and pathology. This review provides a comprehensive examination of SUMOylation's diverse roles within the gut microenvironment. We examine its critical roles in maintaining epithelial barrier integrity, regulating immune responses, and mediating host-microbe interactions, thereby highlighting the complex molecular mechanisms that underpin gut homeostasis. Furthermore, we explore the impact of SUMOylation dysregulation in various intestinal disorders, including inflammatory bowel diseases and colorectal cancer, highlighting its implications as a potential diagnostic biomarker and therapeutic target. By integrating current research findings, this review offers valuable insights into the dynamic interplay between SUMOylation and gut health, paving the way for novel therapeutic strategies aimed at restoring intestinal equilibrium and combating associated pathologies.

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

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

Fraxinellone alleviates colitis-related intestinal fibrosis by blocking the circuit between PD-1+ Th17 cells and fibroblasts

BACKGROUND

Excessive activation of colonic fibroblasts and differentiation of T helper 17 (Th17) cells are the key steps for intestinal fibrogenesis in the process of inflammatory bowel disease (IBD). Although both transforming growth factor-beta (TGF-β)/Mothers Against Decapentaplegic Homolog (SMAD) 3-induced fibroblasts activation and interleukin (IL)-6/signal transducer and activator of transcription (STAT) 3-induced Th17 differentiation have been well studied, the crosstalk between fibroblasts and Th17 cells in the process of intestinal fibrogenesis needs to be unveiled.

METHODS

In this study, the activation of colonic fibroblasts was induced with dextran sulfate sodium salt (DSS) and TGF-β in vivo and in vitro respectively. P-SMAD3 and its downstream targets were quantified using RT-PCR, western blot and immunofluorescence. The differentiation of programmed death 1 (PD-1) + Th17 and activation of fibroblasts were quantified by FACS. PD-1+ Th17 cells and fibroblasts were co-cultured and cytokines in the supernatant were tested by ELISA. The anti-fibrosis effects of different chemical compounds were validated in vitro and further confirmed in vivo.

RESULTS

The colonic fibroblasts were successfully activated by DSS and TGF-β in vivo and in vitro respectively, as activation markers of fibroblasts (p-SMAD3 and its downstream targets such as Acta2, Col1a1 and Ctgf) were significantly increased. The activated fibroblasts produced more IL-6 compared with their inactivated counterparts in vivo and in vitro. The proinflammatory cytokine IL-6 induced PD-1+ Th17 differentiation and TGF-β that in return promoted the activation of colonic fibroblasts. Fraxinellone inhibited TGF-β+ PD-1+ Th17 cells via deactivating STAT3.

CONCLUSIONS

The reciprocal stimulation constructed a circuit of PD-1+ Th17 cells and fibroblasts that accelerated the fibrosis process. Fraxinellone was selected as the potential inhibitor of the circuit of PD-1+ Th17 cells and fibroblasts in vivo and in vitro. Inhibiting the circuit of PD-1+ Th17 cells and fibroblasts could be a promising strategy to alleviate intestinal fibrosis.

Elevated Inflammation Associated with Markers of Neutrophil Function and Gastrointestinal Disruption in Pilot Study of Plasmodium fragile Co-Infection of ART-Treated SIVmac239+ Rhesus Macaques

Human immunodeficiency virus (HIV) and malaria, caused by infection with Plasmodium spp., are endemic in similar geographical locations. As a result, there is high potential for HIV/Plasmodium co-infection, which increases the pathology of both diseases. However, the immunological mechanisms underlying the exacerbated disease pathology observed in co-infected individuals are poorly understood. Moreover, there is limited data available on the impact of Plasmodium co-infection on antiretroviral (ART)-treated HIV infection. Here, we used the rhesus macaque (RM) model to conduct a pilot study to establish a model of Plasmodium fragile co-infection during ART-treated simian immunodeficiency virus (SIV) infection, and to begin to characterize the immunopathogenic effect of co-infection in the context of ART. We observed that P. fragile co-infection resulted in parasitemia and anemia, as well as persistently detectable viral loads (VLs) and decreased absolute CD4+ T-cell counts despite daily ART treatment. Notably, P. fragile co-infection was associated with increased levels of inflammatory cytokines, including monocyte chemoattractant protein 1 (MCP-1). P. fragile co-infection was also associated with increased levels of neutrophil elastase, a plasma marker of neutrophil extracellular trap (NET) formation, but significant decreases in markers of neutrophil degranulation, potentially indicating a shift in the neutrophil functionality during co-infection. Finally, we characterized the levels of plasma markers of gastrointestinal (GI) barrier permeability and microbial translocation and observed significant correlations between indicators of GI dysfunction, clinical markers of SIV and Plasmodium infection, and neutrophil frequency and function. Taken together, these pilot data verify the utility of using the RM model to examine ART-treated SIV/P. fragile co-infection, and indicate that neutrophil-driven inflammation and GI dysfunction may underlie heightened SIV/P. fragile co-infection pathogenesis.

Autism spectrum disorder and a possible role of anti-inflammatory treatments: experience in the pediatric allergy/immunology clinic

Autism spectrum disorder (ASD1) is a behaviorally defined syndrome encompassing a markedly heterogeneous patient population. Many ASD subjects fail to respond to the 1st line behavioral and pharmacological interventions, leaving parents to seek out other treatment options. Evidence supports that neuroinflammation plays a role in ASD pathogenesis. However, the underlying mechanisms likely vary for each ASD patient, influenced by genetic, epigenetic, and environmental factors. Although anti-inflammatory treatment measures, mainly based on metabolic changes and oxidative stress, have provided promising results in some ASD subjects, the use of such measures requires the careful selection of ASD subjects based on clinical and laboratory findings. Recent progress in neuroscience and molecular immunology has made it possible to allow re-purposing of currently available anti-inflammatory medications, used for autoimmune and other chronic inflammatory conditions, as treatment options for ASD subjects. On the other hand, emerging anti-inflammatory medications, including biologic and gate-keeper blockers, exert powerful anti-inflammatory effects on specific mediators or signaling pathways. It will require both a keen understanding of the mechanisms of action of such agents and the careful selection of ASD patients suitable for each treatment. This review will attempt to summarize the use of anti-inflammatory agents already used in targeting ASD patients, and then emerging anti-inflammatory measures applicable for ASD subjects based on scientific rationale and clinical trial data, if available. In our experience, some ASD patients were treated under diagnoses of autoimmune/autoinflammatory conditions and/or post-infectious neuroinflammation. However, there are little clinical trial data specifically for ASD subjects. Therefore, these emerging immunomodulating agents for potential use for ASD subjects will be discussed based on preclinical data, case reports, or data generated in patients with other medical conditions. This review will hopefully highlight the expanding scope of immunomodulating agents for treating neuroinflammation in ASD subjects.

Association between Circulating T Cells and the Gut Microbiome in Healthy Individuals: Findings from a Pilot Study

Though the microbiome's impact on immune system homeostasis is well documented, the effect of circulating T cells on the gut microbiome remains unexamined. We analyzed data from 50 healthy volunteers in a pilot trial of aspirin, using immunophenotyping and 16S rRNA sequencing to evaluate the effect of baseline T cells on microbiome changes over 6 weeks. We employed an unsupervised sparse canonical correlation analysis (sCCA) and used multivariable linear regression models to evaluate the association between selected T cell subsets and selected bacterial genera after adjusting for covariates. In the cross-sectional analysis, percentages of naïve CD4+ T cells were positively associated with a relative abundance of Intestinimonas, and the percentage of activated CD8+ T cells was inversely associated with Cellulosibacter. In the longitudinal analysis, the baseline percentages of naïve CD4+ T cells and activated CD4+ T cells were inversely associated with a 6-week change in the relative abundance of Clostridium_XlVb and Anaerovorax, respectively. The baseline percentage of terminal effector CD4+ T cells was positively associated with the change in Flavonifractor. Notably, the microbiome taxa associated with T cell subsets exclusively belonged to the Bacillota phylum. These findings can guide future experimental studies focusing on the role of T cells in impacting gut microbiome homeostasis.

Ca2+-Dependent Processes of Innate Immunity in IBD

IBD is an uncontrolled inflammatory condition of the gastrointestinal tract, which mainly manifests in two forms: ulcerative colitis (UC) and Crohn's disease (CD). The pathogenesis of IBD appears to be associated with an abnormal response of innate and adaptive immune cells. Innate immunity cells, such as macrophages, mast cells, and granulocytes, can produce proinflammatory (e.g., TNF-α) and oxidative stress (ROS) mediators promoting intestinal damage, and their abnormal responses can induce an imbalance in adaptive immunity, leading to the production of inflammatory cytokines that increase innate immune damage, abate intestinal barrier functions, and aggravate inflammation. Considering that Ca2+ signalling plays a key role in a plethora of cellular functions, this review has the purpose of deepening the potential Ca2+ involvement in IBD pathogenesis.

Insights into Intrinsic Atopic Dermatitis: immunogenicity, Dysbiosis, and Imaging (Reflectance Confocal Microscopy, Optical Coherence Tomography)

Atopic dermatitis (AD) is a frequent inflammatory condition that usually begins during early childhood, but it increasingly starts to debut, even in the elderly. Based on immunoglobulin E (IgE) levels and clinical features, two subsets of this disease have been recognized: intrinsic and extrinsic. When speaking about AD, most specialists think about filaggrin (FLG) mutations resulting in epidermal barrier defects, which is the case in most atopic patients, but some have a normal barrier, as seen by imaging, and still have specific clinical lesions along with metal allergies. Specific molecules (IL-10, IFN-γ, and HBD-3) have been shown to greatly impact the interactions between internal and external factors in this peculiar form of AD. A less-known protein, suprabasin, has been highlighted as a promising explanation for nickel anomalies in intrinsic AD.

Role of the intestinal microbiota in host defense against respiratory viral infections

Viral infections, including those affecting the respiratory tract, can alter the composition of the intestinal microbiota, which, in turn, can significantly influence both innate and adaptive immune responses, resulting in either enhanced pathogen clearance or exacerbation of the infection, possibly leading to inflammatory complications. A deeper understanding of the interplay between the intestinal microbiota and host immune responses in the context of respiratory viral infections (i.e. the gut-lung axis) is necessary to develop new treatments. This review highlights key mechanisms by which the intestinal microbiota, including its metabolites, can act locally or at distant organs to combat respiratory viruses. Therapeutics aimed at harnessing the microbiota to prevent and/or help treat respiratory viral infections represent a promising avenue for future investigation.

Environmental and Microbial Factors in Inflammatory Bowel Disease Model Establishment: A Review Partly through Mendelian Randomization

Inflammatory bowel disease (IBD) is a complex condition resulting from environmental, microbial, immunologic, and genetic factors. With the advancement of Mendelian randomization research in IBD, we have gained new insights into the relationship between these factors and IBD. Many animal models of IBD have been developed using different methods, but few studies have attempted to model IBD by combining environmental factors and microbial factors. In this review, we examine how environmental factors and microbial factors affect the development and progression of IBD, and how they interact with each other and with the intestinal microbiota. We also summarize the current methods for creating animal models of IBD and compare their advantages and disadvantages. Based on the latest findings from Mendelian randomization studies on the role of environmental factors in IBD, we discuss which environmental and microbial factors could be used to construct a more realistic and reliable IBD experimental model. We propose that animal models of IBD should consider both environmental and microbial factors to better mimic human IBD pathogenesis and to reveal the underlying mechanisms of IBD at the immune and genetic levels. We highlight the importance of environmental and microbial factors in IBD pathogenesis and offer new perspectives and suggestions for improving experimental animal modeling. Our goal is to create a model that closely resembles the clinical picture of IBD.

Amyloid, Crohn's disease, and Alzheimer's disease - are they linked?

Crohn's disease (CD) is a chronic inflammatory disease that most frequently affects part of the distal ileum, but it may affect any part of the gastrointestinal tract. CD may also be related to systemic inflammation and extraintestinal manifestations. Alzheimer's disease (AD) is the most common neurodegenerative disease, gradually worsening behavioral and cognitive functions. Despite the meaningful progress, both diseases are still incurable and have a not fully explained, heterogeneous pathomechanism that includes immunological, microbiological, genetic, and environmental factors. Recently, emerging evidence indicates that chronic inflammatory condition corresponds to an increased risk of neurodegenerative diseases, and intestinal inflammation, including CD, increases the risk of AD. Even though it is now known that CD increases the risk of AD, the exact pathways connecting these two seemingly unrelated diseases remain still unclear. One of the key postulates is the gut-brain axis. There is increasing evidence that the gut microbiota with its proteins, DNA, and metabolites influence several processes related to the etiology of AD, including β-amyloid abnormality, Tau phosphorylation, and neuroinflammation. Considering the role of microbiota in both CD and AD pathology, in this review, we want to shed light on bacterial amyloids and their potential to influence cerebral amyloid aggregation and neuroinflammation and provide an overview of the current literature on amyloids as a potential linker between AD and CD.

Exploration of the core pathway of inflammatory bowel disease complicated with metabolic fatty liver and two-sample Mendelian randomization study of the causal relationships behind the disease

Background

Inflammatory bowel disease (IBD) is often associated with complex extraintestinal manifestations. The incidence of nonalcoholic fatty liver disease (NAFLD) in IBD populations is increasing yearly. However, the mechanism of interaction between NAFLD and IBD is not clear. Consequently, this study aimed to explore the common genetic characteristics of IBD and NAFLD and identify potential therapeutic targets.

Materials and methods

Gene chip datasets for IBD and NAFLD were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was performed to identify modules in those datasets related to IBD and NAFLD. ClueGO was used for biological analysis of the shared genes between IBD and NAFLD. Based on the Human MicroRNA Disease Database (HMDD), microRNAs (miRNAs) common to NAFLD and IBD were obtained. Potential target genes for the miRNAs were predicted using the miRTarbase, miRDB, and TargetScan databases. Two-sample Mendelian randomization (MR) and two-way MR were used to explore the causal relationship between Interleukin-17 (IL-17) and the risk of IBD and NAFLD using data from GWAS retrieved from an open database.

Results

Through WGCNA, gene modules of interest were identified. GO enrichment analysis using ClueGO suggested that the abnormal secretion of chemokines may be a common pathophysiological feature of IBD and NAFLD, and that the IL-17-related pathway may be a common key pathway for the pathological changes that occur in IBD and NAFLD. The core differentially expressed genes (DEGs) in IBD and NAFLD were identified and included COL1A1, LUM, CCL22, CCL2, THBS2, COL1A2, MMP9, and CXCL8. Another cohort was used for validation. Finally, analysis of the miRNAs identified potential therapeutic targets. The MR results suggested that although there was no causal relationship between IBD and NAFLD, there were causal relationships between IL-17 and IBD and NAFLD.

Conclusion

We established a comorbid model to explain the potential mechanism of IBD with NAFLD and identified the chemokine-related pathway mediated by cytokine IL-17 as the core pathway in IBD with NAFLD, in which miRNA also plays a role and thus provides potential therapeutic targets.