Evidence for continuous stimulation of interleukin-6 production in Crohn's disease

Exploring the therapeutic potential of interleukin-6 receptor blockade in autoimmune diseases using drug target mendelian randomization

The blockade of the interleukin 6 receptor (IL-6R) demonstrates significant potential in various autoimmune diseases (ADs); however, the underlying therapeutic efficacy associated with this approach remains elusive. We conducted a comprehensive Mendelian randomization (MR) analysis based on large-scale genome-wide association studies to investigate the causal relationships between genetically proxied IL-6R blockade weighted by serum C-reactive protein levels and eighteen common ADs. Rheumatoid arthritis, COVID-19 infection, and COVID-19 critical illness were utilized as positive controls. The inverse-variance weighted (IVW) method was utilized as the primary analytical tool, while genetic colocalization analysis was conducted to further substantiate the causalities. Genetically proxied IL-6R blockade exhibited causally protective effects on all positive control diseases. After Bonferroni correction to IVW estimates, genetically proxied IL-6R blockade may significantly increase the risk of asthma (OR=1.031, P=2.15×10-12) and eczema (OR=1.066, P=5.92×10-22), while reducing the risk of ankylosing spondylitis (OR=0.341, P=1.39×10-5), Crohn's disease (OR=0.556, P=2.21×10-3), and type 1 diabetes (OR=0.410, P=1.78×10-7). Additionally, genetically proxied IL-6R blockade would suggestively reduce the risk of multiple sclerosis (OR=0.713, P=1.13×10-2). The results were robust under sensitivity analysis. For genetic colocalization analysis, we identified a shared causal variant rs531479718 linking serum C-reactive protein levels and asthma (posterior probability H4=0.998). Overall, our MR study demonstrated that genetically proxied IL-6R blockade may be causally associated with an increased risk of asthma and eczema, while concurrently diminishing the risk of ankylosing spondylitis, Crohn's disease, type 1 diabetes, and multiple sclerosis. These findings carry substantial implications for informing the therapeutic utilization of IL-6R blockade in the management of ADs.

The importance of growth differentiation factor 15 and interleukin 6 serum levels in inflammatory bowel diseases

There are only scarce recent reports about the role of growth differentiation factor 15 (GDF-15) and some more data about interleukin-6 (IL-6) in inflammatory bowel diseases (IBD). We assessed GDF-15 and IL-6 serum levels in patients with IBD and associations with their characteristics. We included 122 and 71 stored samples from patients with Crohn's disease (CD) and ulcerative colitis (UC), respectively, and regular follow-up and 44 samples from healthy controls. Data regarding epidemiologic and disease characteristics were recorded. In CD, both GDF-15 and IL-6 levels were higher in active disease or all patients than controls (P ≤ 0.020) as well as patients with elevated CRP (P ≤ 0.008), endoscopically active disease (P ≤ 0.017), age ≥ 40 years (P ≤ 0.005) and active smokers (P ≤ 0.050) and were positively correlated with hospitalization numbers (P ≤ 0.019). GDF-15 levels were also positively correlated with flares within year-1 (P < 0.001). In UC, both GDF-15 and IL-6 levels were higher in clinically active or all patients than controls (P < 0.001), but they shared no other association with patient characteristics except for positive correlation with CRP. Only IL-6 levels were higher in active than inactive UC either clinically (P = 0.047) or endoscopically (P < 0.001) and were positively correlated with stool calprotectin (P = 0.021). GDF-15 was positively correlated to IL-6 levels only in UC (rs=0.591, P < 0.001) but not in CD. In conclusion, in CD, GDF-15 and IL-6 levels could constitute indexes of activity and even offer a prognostic index of disease progression. In UC, IL-6 could also represent an activity index, but the role of GDF-15 needs further evaluation.

[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.

Biomarkers in inflammatory bowel disease: a practical guide

Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn's disease (CD), is a costly condition in terms of morbidity and healthcare utilization, with an increasing prevalence now approaching 1% in the Western world. Endoscopic assessment of IBD remains the gold standard for diagnosis, evaluation of treatment response and determination of post-operative recurrence, but is expensive and invasive. Biomarkers can facilitate non-invasive disease assessment, with C-reactive protein and faecal calprotectin as the most widely available biomarkers in current clinical practice. This narrative review summarizes the evidence for their use in both UC and CD and offers practical guidance for healthcare providers taking into account the limitations of biomarker interpretation. We present evidence for the future use of novel biomarkers in IBD and discuss how biomarker discovery could deliver the goal of precision medicine in IBD.

hUC-MSCs therapy for Crohn's disease: efficacy in TNBS-induced colitis in rats and pilot clinical study

BACKGROUND

The use of mesenchymal stem cells (MSCs) has recently emerged as a promising new therapeutic strategy for many diseases including perianal fistulizing Crohn's disease (CD). Whether hUC-MSCs can promote the healing of luminal ulcer in CD has not been studied so far.

METHODS

The model of TNBS-induced colitis in rats was used to confirm the efficacy of hUC-MSCs in the treatment of CD. Then, seventeen CD patients refractory to or unsuitable for currently available therapies were enrolled and received once submucosal local injection through colonoscopy combined with once intravenous drip on the next day. All patients received a 24-week follow-up. Clinical and laboratory assessments were monitored at baseline, week 4, 8, 12, and 24. Endoscopic evaluations were conducted at baseline and week 12. Mucosal specimens were obtained at the margin of lesions by endoscopy biopsies and used for RNA sequencing. Two hUC-MSCs co-culture systems were established in vitro, one with the mucosa specimens and the other with M1 macrophages induced from THP1. The expressions of genes representing inflammation (TNFα, IL-6, and IL-1β) and intestinal barrier function (ZO1, CLAUDIN1, and CDH1) were tested by RT-PCR.

FINDINGS

hUC-MSCs treatment increased body weight and decreased disease activity index (DAI), colon macroscopic damage index (CMDI), and histopathological score (HPS) of rats with TNBS-induced colitis. The results of the clinical study also showed that this mode of hUC-MSCs application was associated with regression of intestinal ulceration. Eight patients (47%) got endoscopic responses (SES-CD improvement of ≥50% from baseline) and three patients (17.65%) got mucosal healing (SES-CD is zero), with a parallel improvement of clinical and laboratory parameters without serious adverse events. RNA sequencing showed hUC-MSCs therapy was associated with an upregulation of transcripts linked to intestinal epithelial barrier integrity and a downregulation of inflammatory signaling pathways in the intestinal mucosa, especially the TNF signaling pathway, IL-17 signaling pathway, and TLR signaling pathway. RNA expression of intestinal epithelial tight junction protein (ZO1, CLAUDIN1, and CDH1), and the RNA expression of major intestinal inflammatory factors in CD (IL-1β, IL-6, and TNFα, p < 0.001 for all) were improved significantly. Moreover, hUC-MSCs could attenuate the polarization of M1 macrophage induced from THP1, thereby decreasing the mRNA expression of IL-1β, IL-6, and TNFα significantly (p < 0.05 for all). TSG-6 expression was evaluated in hUC-MSCs culture supernatant after treatment with TNFα, IFNγ, and LPS for 48 h. And hUC-MSCs could inhibit the phosphorylation of JAK/STAT1 in the intestinal mucosa of CD patients.

INTERPRETATION

hUC-MSCs transplantation alleviated TNBS-induced colitis in rats. In this pilot clinical study, preliminary data suggested that this approach to administering hUC-MSCs might have potential for clinical efficacy and manageable safety in treating refractory CD, potentially providing hope for better outcomes. No serious adverse events were observed.

FUNDING

This work was funded by General Program of National Natural Science Foundation of China (Grant No. 82270639), the Scientific research project of Shanghai Municipal Health Committee (Grant No. 202240001), Specialty Feature Construction Project of Shanghai Pudong New Area Health Commission (Grant No. PWZzb2022-05), Shanghai East Hospital Youth Research and Cultivation Foundation program (Grant No. DFPY2022015), Peak Disciplines (Type IV) of Institutions of Higher Learning in Shanghai and Technology Development Project of Pudong Science, Technology and Economic Commission of Shanghai (Grant No. PKJ2021-Y08).

Identification of differentially expressed genes associated with ferroptosis in Crohn's disease

Ferroptosis-related genes may play a critical regulatory role in the pathogenesis of Crohn's disease (CD). The purpose of the present study was to identify genes expressed in CD that are associated with ferroptosis, and to provide guidance in the diagnosis and therapy of CD. CD mRNA expression data were initially gathered from the Gene Expression Omnibus (GEO) database. GSE75214 and GSE102133 datasets were selected as the major targets and were analyzed for differentially expressed genes (DEGs). Subsequently, R software was used to analyze the common genes among the DEGs between CD and ferroptosis-related genes. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genome pathway analysis were conducted to identify related pathways and functions. Protein-protein interaction (PPI) analysis was performed to identify target genes. The DSigDB website was used to predict potential target drugs for hub genes. Reverse transcription-quantitative (RT-q) PCR was employed to detect the expression of these ferroptosis-related genes in clinical samples obtained from healthy controls and patients with CD. According to the two GEO datasets, 13 ferroptosis DEGs (11 upregulated genes and two downregulated genes) were identified in CD with thresholds of P<0.05 and |log2 fold change|>1, and were selected for further analysis. PPI analysis indicated the mutual effects among these genes and filtered out five hub genes. The top 10 potential targeted drugs were selected. The qPCR results showed that the expression levels of three genes, namely, IL-6, prostaglandin-endoperoxide synthase 2 (PTGS2) and dual oxidase 2 (DUOX2), were different between CD samples and healthy samples. This result was consistent with the results obtained from the bioinformatics analysis. In conclusion, bioinformatics analysis identified a total of 13 ferroptosis-associated genes in CD. Further verification by qPCR showed that IL-6, PTGS2 and DUOX2 may affect the process of CD by regulating ferroptosis. These findings might provide new biomarkers, diagnostic and therapeutic markers for CD.

Cytokines of the interleukin-6 family as emerging targets in inflammatory bowel disease

INTRODUCTION

Inflammatory bowel disease (IBD) is an umbrella term that includes different chronic inflammatory diseases of the gastrointestinal tract, most commonly Crohn's disease and ulcerative colitis. IBD affects more than 6 million people worldwide and constitutes not only a debilitating disease for the patients, but also a significant factor for society due to costs for health care and reduced working capacity. Despite the introduction of biologicals for the treatment of IBD, the identification of novel targets that could lead to novel therapeutics is still needed.

AREAS COVERED

In this review, we summarize current knowledge about the interleukin-6 family of cytokines as potential therapeutic targets for improving the therapy of patients with IBD. We discuss cytokines like IL-6 itself for which therapeutics such as inhibitory monoclonal antibodies have already entered the clinics, but also focus on other family members whose therapeutic potential has not been explored yet.

EXPERT OPINION

The different cytokines of the IL-6 family offer multiple therapeutic targets that can potentially be used to treat patients with inflammatory bowel disease, but unwanted side effects like inhibition of epithelial regeneration have to be considered.

Selected Cytokines and Metalloproteinases in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a collective term for two diseases: ulcerative colitis (UC) and Crohn's disease (CD). There are many factors, e.g., genetic, environmental and immunological, that increase the likelihood of these diseases. Indicators of IBDs include extracellular matrix metalloproteinases (MMPs). The aim of this review is to present data on the role of selected cytokines and metalloproteinases in IBD. In recent years, more and more transcriptomic studies are emerging. These studies are improving the characterization of the cytokine microenvironment inside inflamed tissue. It is observed that the levels of several cytokines are consistently increased in inflamed tissue in IBD, both in UC and CD. This review shows that MMPs play a major role in the pathology of inflammatory processes, cancer, and IBD. IBD-associated inflammation is associated with increased expression of MMPs and reduced ability of tissue inhibitors of metalloproteinases (TIMPs) to inhibit their action. In IBD patients in tissues that are inflamed, MMPs are produced in excess and TIMP activity is not sufficient to block MMPs. This review is based on our personal selection of the literature that was retrieved by a selective search in PubMed using the terms "Inflammatory bowel disease" and "pathogenesis of Inflammatory bowel diseases" that includes systematic reviews, meta-analyses, and clinical trials. The involvement of the immune system in the pathophysiology of IBD is reviewed in terms of the role of the cytokines and metalloproteinases involved.

Targeting IL-23 for the interception of obesity-associated colorectal cancer

Inflammation and obesity are two major factors that promote Colorectal cancer (CRC). Our recent data suggests that interleukin (IL)-23, is significantly elevated in CRC tumors and correlates with patient obesity, tumor grade and survival. Thus, we hypothesize that obesity and CRC may be linked via inflammation and IL-23 may be a potential target for intervention in high-risk patients. TCGA dataset and patient sera were evaluated for IL-23A levels. IL-23A [IL-23 p19-/-] knockout (KO) mice were crossed to Apcmin/+ mice and progeny were fed low-fat or high-fat diets. At termination intestines were evaluated for tumorigenesis. Tumors, serum, and fecal contents were analyzed for protein biomarkers, cytokines, and microbiome profile respectively. IL-23A levels are elevated in the sera of patients with obesity and colon tumors. Genetic ablation of IL-23A significantly suppressed colonic tumor multiplicity (76-96 %) and incidence (72-95 %) in male and female mice. Similarly, small-intestinal tumor multiplicity and size were also significantly reduced in IL-23A KO mice. IL-23A knockdown in Apcmin/+ mice fed high-fat diet, also resulted in significant suppression of colonic (50-58 %) and SI (41-48 %) tumor multiplicity. Cytokine profiling showed reduction in several circulating pro-inflammatory cytokines including loss of IL-23A. Biomarker analysis suggested reduced tumor cell proliferation and immune modulation with an increase in tumor-infiltrating CD4+ and CD8+ T-lymphocytes in the IL-23A KO mice compared to controls. Fecal microbiome analysis revealed potentially beneficial changes in the bacterial population profile. In summary, our data indicates a tumor promoting role for IL-23 in CRC including diet-induced obesity. With several IL-23 targeted therapies in clinical trials, there is a great potential for targeting this cytokine for CRC prevention and therapy.

CXCL10 as a shared specific marker in rheumatoid arthritis and inflammatory bowel disease and a clue involved in the mechanism of intestinal flora in rheumatoid arthritis

This study aimed to identify shared specific genes associated with rheumatoid arthritis (RA) and inflammatory bowel disease (IBD) through bioinformatic analysis and to examine the role of the gut microbiome in RA. The data were extracted from the 3 RA and 1 IBD gene expression datasets and 1 RA gut microbiome metagenomic dataset. Weighted correlation network analysis (WGCNA) and machine learnings was performed to identify candidate genes associated with RA and IBD. Differential analysis and two different machine learning algorithms were used to investigate RA's gut microbiome characteristics. Subsequently, the shared specific genes related to the gut microbiome in RA were identified, and an interaction network was constructed utilizing the gutMGene, STITCH, and STRING databases. We identified 15 candidates shared genes through a joint analysis of the WGCNA for RA and IBD. The candidate gene CXCL10 was identified as the shared hub gene by the interaction network analysis of the corresponding WGCNA module gene to each disease, and CXCL10 was further identified as the shared specific gene by two machine learning algorithms. Additionally, we identified 3 RA-associated characteristic intestinal flora (Prevotella, Ruminococcus, and Ruminococcus bromii) and built a network of interactions between the microbiomes, genes, and pathways. Finally, it was discovered that the gene CXCL10 shared between IBD and RA was associated with the three gut microbiomes mentioned above. This study demonstrates the relationship between RA and IBD and provides a reference for research into the role of the gut microbiome in RA.

Role of interleukin-6-mediated inflammation in the pathogenesis of inflammatory bowel disease: focus on the available therapeutic approaches and gut microbiome

Inflammatory bowel disease (IBD) is considered a chronic inflammatory and multifactorial disease of the gastrointestinal tract. Crohn's disease (CD) and ulcerative colitis (UC) are two types of chronic IBD. Although there is no accurate information about IBD pathophysiology, evidence suggests that various factors, including the gut microbiome, environment, genetics, lifestyle, and a dysregulated immune system, may increase susceptibility to IBD. Moreover, inflammatory mediators such as interleukin-6 (IL-6) are involved in the immunopathogenesis of IBDs. IL-6 contributes to T helper 17 (Th17) differentiation, mediating further destructive inflammatory responses in CD and UC. Moreover, Th1-mediated responses participate in IBD, and the antiapoptotic IL-6/IL-6 receptor (IL-6R)/signal transducer and activator of transcription 3 (STAT3) signals are responsible for preserving Th1 cells in the site of inflammation. It has been revealed that fecal bacteria isolated from UC-active and UC-remission patients stimulate the hyperproduction of several cytokines, such as IL-6, tumor necrosis factor-α (TNF-α), IL-10, and IL-12. Given the importance of the IL-6/IL-6R axis, various therapeutic options exist for controlling or treating IBD. Therefore, alternative therapeutic approaches such as modulating the gut microbiome could be beneficial due to the failure of the target therapies so far. This review article summarizes IBD immunopathogenesis focusing on the IL-6/IL-6R axis and discusses available therapeutic approaches based on the gut microbiome alteration and IL-6/IL-6R axis targeting and treatment failure.

The interleukin-6 family in tissues is closely related to the clinical outcomes of oral lichen planus

OBJECTIVE

We attempted to investigate the role of interleukin-6 (IL-6) family expression in local tissues as it relates to presentations and outcomes in oral lichen planus (OLP), which is a common chronic inflammatory oral disease.

MATERIALS AND METHODS

A clinical follow-up cohort of OLP patients was established, and a biological sample library was constructed with categorization into erosive type (EOLP) and nonerosive type (NEOLP). Transcriptome sequencing of the lesions was then performed. A multiple regression model was used to explore the differences in IL-6 family expression among patients with different clinical types and clinical outcomes.

RESULTS

OLP tissue transcriptome sequencing showed that IL-6 family expression in EOLP increased significantly. It was also found that IL-6 family factors in the OLP recurrent erosion group were significantly increased compared to the persistent nonerosion group. Based on the multiple regression analysis of the OLP clinical cohort, it was found that the increased expression of the IL-6 family was closely related to the clinical types and clinical outcomes of OLP.

CONCLUSION

The high expression of the IL-6 family is closely related to the erosion of local mucosa and poor prognosis of OLP patients. IL-6-related factors may be used as therapeutic targets for OLP patients.

Idiopathic pulmonary fibrosis and intestinal disorders: An observational study

BACKGROUND AND AIM

Idiopathic pulmonary fibrosis (IPF) is a chronic respiratory disease characterized by a progressive decline in lung function and a specific histopathologic pattern defined as usual interstitial pneumonia. Early diagnosis and new therapeutic protocols have contributed to a reduction in disease progression. Thus, some patients may develop extrapulmonary diseases including malignancies and chronic pathologies. The aim of this study was to investigate the frequency of intestinal disorders such as polyps, colorectal carcinoma (CRC), and chronic inflammatory bowel disease (IBD) in patients with IPF.

METHODS

From the database of 189 patients with IPF (148 males, 78.3 %; 41 females, 21.7 %) residing in the district of Modena, we identified 44 patients (36 males, 81.8 %; 8 females, 18.2 %) with a histologically confirmed intestinal disease.

RESULTS

Intestinal polyps were detected in 41 cases (93.2 %), of which 4 were associated with CRC and 1 with IBD; 1 patient had only CRC (2.3 %), and 2 patients had only IBD (4.5 %). Both males and females developed bowel disease, but males seemed to have a higher number of polyps and high-grade adenomas with a predisposition to malignant transformation.

CONCLUSIONS

As patients with IPF may present with intestinal diseases that can evolve into malignancies in some cases, they should undergo appropriate follow-up and targeted colorectal screening. Thus, colorectal pathologies should not take a back seat. These preliminary results encourage further research to select suitable patients for specific diagnostic and therapeutic procedures in order to prolong survival and improve the quality of life.

Risk of Recurrent Acute Arterial Events Associated With Thiopurines and Anti-Tumor Necrosis Factor in Inflammatory Bowel Diseases

BACKGROUND & AIMS

Patients with inflammatory bowel disease (IBD) are at increased risk of acute arterial events. Treatment with anti-tumor necrosis factor (anti-TNF) agents has been associated with a protective effect against the first occurrence of acute arterial events, but the impact of treatment with anti-TNF in patients with a previous history of acute arterial events remains unclear. We assessed the effect of anti-TNF and thiopurines on the risk of recurrent acute arterial events in patients with IBD in a nationwide cohort.

METHODS

Based on the French nationwide health insurance database, patients with IBD and a previous history of an acute arterial event were followed up from January 1, 2009, until December 31, 2018. The risk of acute arterial event recurrence associated with anti-TNF and thiopurine exposure was assessed using marginal structural Cox proportional hazard models adjusted for baseline and time-varying covariates.

RESULTS

A total of 27,185 patients were included. During 121,822 person-years (median follow-up period, 4.0 y), 6865 recurrent acute arterial events occurred (incidence rate per 1000 person-years, 56.4; 95% CI, 55.0-57.7). Exposure to both anti-TNF and thiopurines were associated with a decreased risk of recurrent acute arterial events compared with the absence of exposure to either treatment (hazard ratio, 0.75; 95% CI, 0.63-0.90 and hazard ratio, 0.76; 95% CI, 0.66-0.88, respectively).

CONCLUSIONS

In a nationwide cohort study of patients with IBD and a previous history of an acute arterial event, exposure to both anti-TNF and thiopurines were associated with a decreased risk of recurrent acute arterial events.

Olmesartan medoxomil self-microemulsifying drug delivery system reverses apoptosis and improves cell adhesion in trinitrobenzene sulfonic acid-induced colitis in rats

Olmesartan medoxomil (OM) is an angiotensin receptor blocker. This study aimed to investigate the effects of OM self-microemulsifying drug delivery system (OMS) in trinitrobenzene sulfonic acid (TNBS)-induced acute colitis in rats. Besides two control groups, five TNBS-colitic-treated groups (n = 8) were given orally sulfasalazine (100 mg/kg/day), low and high doses of OM (3.0 and 10.0 mg/kg/day) (OML and OMH) and of OMS (OMSL and OMSH) for seven days. A colitis activity score was calculated. The colon was examined macroscopically. Colonic levels of myeloperoxidase, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), malondialdehyde, and reduced glutathione were measured. Plasma and colonic olmesartan levels were measured. Colonic sections were subjected to hematoxylin and eosin staining and immunohistochemical staining for E-cadherin, caspase-3, and matrix metalloproteinase-9 (MMP-9). Protein expression of E-cadherin, Bcl-2 associated X protein (Bax), and B-cell lymphoma 2 (Bcl-2), and cleaved caspase-3 by Western blot was done. TNBS-colitic rats showed increased colonic myeloperoxidase, TNF-α, IL-6, and malondialdehyde, decreased colonic glutathione, histopathological, immunohistochemical, and protein expression alterations. OMS, compared with OM, dose-dependently achieved higher colonic free olmesartan concentration, showed better anti-inflammatory, antioxidant, and anti-apoptotic effects, improved intestinal barrier, and decreased mucolytic activity. OMS more effectively up-regulated the reduced Bcl-2, Bcl-2/Bax ratio, and E-cadherin expression, and down-regulated the overexpressed Bax, cleaved caspase-3, and MMP-9. OMSL exerted effects comparable to OMH. Sulfasalazine exerted maximal colonic protective effects and almost completely reversed colonic damage, and OMSH showed nearly similar effects with non-significant differences in-between or compared with the normal control group. In conclusion, OMS could be a potential additive treatment for Crohn's disease colitis.

Association of inflammatory bowel disease with suicidal ideation, suicide attempts, and suicide: A systematic review and meta-analysis

OBJECTIVE

Inflammatory bowel disease (IBD) is associated with psychiatric comorbidities. However, the association between IBD and suicidal ideation or suicide attempts has not been well established. This study aimed to perform a systematic review and meta-analysis to elucidate the relationship between IBD and suicidal ideation, suicide attempts, and suicide.

METHODS

We systematically searched five electronic databases - PubMed, Embase, CENTRAL, Web of Science, and PsycINFO - from their inception to January 28, 2022. Quality assessment, data synthesis, subgroup analyses, sensitivity analyses, and publication bias assessment were performed on the included studies.

RESULTS

We identified 28 studies with 1,047,755 patients with IBD. The pooled prevalence of suicidal ideation in patients with IBD was 17.3% (95% CI, 9.5%-25.2%). Patients with IBD were associated with an increased risk of suicide attempts (relative risk [RR], 1.39; 95% CI, 1.08-1.79) and suicide deaths (RR, 1.25; 95% CI, 1.09-1.43) than the controls without IBD. Patients with Crohn's disease subtypes, female IBD, pediatric-onset IBD, young adult IBD, and short-duration IBD had a particularly high risk for suicide.

CONCLUSION

Patients with IBD had a high prevalence of suicidal ideation and a significantly higher likelihood of suicide attempts and suicide. Caring for patients with IBD, including their mental health needs, may require concerted efforts among gastroenterologists and other healthcare providers.

Model Informed Precision Dosing Tool Forecasts Trough Infliximab and Associates with Disease Status and Tumor Necrosis Factor-Alpha Levels of Inflammatory Bowel Diseases

Background: Substantial inter-and intra-individual variability of Infliximab (IFX) pharmacokinetics necessitates tailored dosing approaches. Here, we evaluated the performances of a Model Informed Precision Dosing (MIPD) Tool in forecasting trough Infliximab (IFX) levels in association with disease status and circulating TNF-α in patients with Inflammatory Bowel Diseases (IBD). Methods: Consented patients undergoing every 8-week maintenance therapy with IFX were enrolled. Midcycle specimens were collected, IFX, antibodies to IFX, albumin were determined and analyzed with weight using nonlinear mixed effect models coupled with Bayesian data assimilation to forecast trough levels. Accuracy of forecasted as compared to observed trough IFX levels were evaluated using Demings’s regression. Association between IFX levels, CRP-based clinical remission and TNF-α levels were analyzed using logistic regression and linear mixed effect models. Results: In 41 patients receiving IFX (median dose = 5.3 mg/Kg), median IFX levels decreased from 13.0 to 3.9 µg/mL from mid to end of cycle time points, respectively. Midcycle IFX levels forecasted trough with Deming’s slope = 0.90 and R2 = 0.87. Observed end cycle and forecasted trough levels above 5 µg/mL associated with CRP-based clinical remission (OR = 7.2 CI95%: 1.7−30.2; OR = 21.0 CI95%: 3.4−127.9, respectively) (p < 0.01). Median TNF-α levels increased from 4.6 to 8.0 pg/mL from mid to end of cycle time points, respectively (p < 0.01). CRP and TNF-α levels associated independently and additively to decreased IFX levels (p < 0.01). Conclusions: These data establish the value of our MIPD tool in forecasting trough IFX levels in patients with IBD. Serum TNF-α and CRP are reflective of inflammatory burden which impacts exposure.

In silico screening for oligopeptides useful as capture and reporting probes for interleukin-6 biosensing

IL-6 is an important interleukin associated with inflammation and several diseases such as cancer. Evaluation of its levels in human blood sera is a critical step for an accurate diagnosis of the diseases. Our goal is to design peptides that can selectively bind in different poses with good affinities to IL-6. For this purpose, we started from the crystal structures of different IL-6/protein complexes available in the Protein Data Bank (PDB) to select short peptides in the interaction zones, in which we intentionally introduced point mutations to increase their stability and affinity. To examine their usefulness as capture and reporting probes for the IL-6 biosensing, the five peptides and their interaction with IL-6 were studied in saline aqueous solution. Molecular docking, MD, and MM-PBSA were used to investigate the affinity and stability of these complexes. The conformational changes, the distance between the mass centers, the gyration radii, and the numbers of hydrogen bonds were analyzed to select the most suitable candidates. Three peptides, namely CTE17, CAY15 and CSE25, have the highest affinities presenting significant numbers of residues that have contact frequencies greater than 50% of simulation run time and are the most promising candidates. CTE17 and CSE25 showed they can form a stable sandwich with the target protein. For sake of comparison, we examined the previously known peptides (FND20, INL19 and CEK17) having affinity to IL-6 and the affinity of the lead i.e. CSE25 to two other interleukin family members (IL-4 and to IL-10).

Dietary Interventions Ameliorate Infectious Colitis by Restoring the Microbiome and Promoting Stem Cell Proliferation in Mice

Decreases in short-chain-fatty-acids (SCFAs) are linked to inflammatory bowel disease (IBD). Yet, the mechanisms through which SCFAs promote wound healing, orchestrated by intestinal stem cells, are poorly understood. We discovered that, in mice with Citrobacter rodentium (CR)-induced infectious colitis, treatment with Pectin and Tributyrin diets reduced the severity of colitis by restoring Firmicutes and Bacteroidetes and by increasing mucus production. RNA-seq in young adult mouse colon (YAMC) cells identified higher expression of Lgr4, Lgr6, DCLK1, Muc2, and SIGGIR after Butyrate treatment. Lineage tracing in CR-infected Lgr5-EGFP-IRES-CreERT2/ROSA26-LacZ (Lgr5-R) mice also revealed an expansion of LacZ-labeled Lgr5(+) stem cells in the colons of both Pectin and Tributyrin-treated mice compared to control. Interestingly, gut microbiota was required for Pectin but not Tributyrin-induced Lgr5(+) stem cell expansion. YAMC cells treated with sodium butyrate exhibited increased Lgr5 promoter reporter activity due to direct Butyrate binding with Lgr5 at -4.0 Kcal/mol, leading to thermal stabilization. Upon ChIP-seq, H3K4me3 increased near Lgr5 transcription start site that contained the consensus binding motif for a transcriptional activator of Lgr5 (SPIB). Thus, a multitude of effects on gut microbiome, differential gene expression, and/or expansion of Lgr5(+) stem cells seem to underlie amelioration of colitis following dietary intervention.

Utilization of physiologically-based pharmacokinetic model to assess disease-mediated therapeutic protein-disease-drug interaction in immune-mediated inflammatory diseases

It is known that interleukin-6 (IL-6) can significantly modulate some key drug-metabolizing enzymes, such as phase I cytochrome P450s (CYPs). In this study, a physiologically-based pharmacokinetic (PBPK) model was developed to assess CYPs mediated therapeutic protein drug interactions (TP-DIs) in patients with immune-mediated inflammatory diseases (IMIDs) with elevated systemic IL-6 levels when treated by anti-IL-6 therapies. Literature data of IL-6 levels in various diseases were incorporated in SimCYP to construct respective virtual patient populations. The modulation effects of systemic IL-6 level and local IL-6 level in the gastrointestinal tract (GI) on CYPs activities were assessed. Upon blockade of the IL-6 signaling pathway by an anti-IL-6 treatment, the area under plasma concentration versus time curves (AUCs) of S-warfarin, omeprazole, and midazolam were predicted to decrease by up to 40%, 42%, and 46%, respectively. In patients with Crohn's disease and ulcerative colitis treated with an anti-IL-6 therapy, the lowering of the elevated IL-6 levels in the local GI tissue were predicted to result in further decreases in AUCs of those CYP substrates. The propensity of TP-DIs under comorbidity conditions, such as in patients with cancer with IMID, were also explored. With further validation with relevant clinical data, this PBPK model may provide an in silico way to quantify the magnitude of potential TP-DI in patients with elevated IL-6 levels when an anti-IL-6 therapeutic is used with concomitant small-molecule drugs. This model may be further adapted to evaluate the CYP modulation effect by other therapeutic modalities, which would significantly alter levels of proinflammatory cytokines during the treatment period.

Proteinuria Is Associated with the Development of Crohn's Disease: A Nationwide Population-Based Study

BACKGROUND AND AIMS

The impact of proteinuria and its severity on the incidence of inflammatory bowel disease (IBD) has not yet been studied. We aimed to determine the association between proteinuria measured by urine dipstick tests and the development of IBD.

METHODS

This nationwide population-based study was conducted using the Korean National Health Insurance Service (NHIS) database. A total of 9,917,400 people aged 20 years or older who had undergone a national health examination conducted by the NHIS in 2009 were followed up until 2017. The study population was classified into four groups-negative, trace, 1+, and ≥ 2+-according to the degree of proteinuria measured by the urine dipstick test. The primary endpoint was newly diagnosed IBD, Crohn's disease (CD), or ulcerative colitis (UC) during the follow-up period.

RESULTS

Compared with the dipstick-negative group, the incidence of CD significantly increased according to the degree of proteinuria (adjusted hazard ratio [aHR] with 95% confidence interval [CI], 1.01 [0.703-1.451], 1.515 [1.058-2.162], and 2.053 [1.301-3.24] in the trace, 1+, and ≥ 2+ dipstick groups, respectively; p for trend 0.007). However, there was no significant difference in the incidence of UC according to the degree of proteinuria (aHR with 95% CI, 1.12 [0.949-1.323], 0.947 [0.764-1.174], and 1.009 [0.741-1.373] in the trace, 1+, and ≥ 2+ dipstick groups, respectively; p for trend 0.722). In the subgroup analysis, dipstick-positive proteinuria independently increased the incidence of CD regardless of the subgroup. However, dipstick-positive proteinuria was associated with the risk of UC in those with diabetes mellitus and not in those without diabetes mellitus (aHR, 1.527 vs. 0.846; interaction p-value 0.004). The risk of CD was increased or decreased according to proteinuria changes but not associated with the risk of UC.

CONCLUSION

Proteinuria, measured by the dipstick test, is strongly associated with the development of CD.

Laboratory Assessment of Disease Activity in Pediatric Patients with Inflammatory Bowel Disease: What’s New?

Laboratory tests are an integral part of both the diagnostic and follow-up algorithm of patients with inflammatory bowel disease (IBD). Their advantages over other non-invasive methods for assessing disease activity are greater objectivity than clinical activity indices and imaging studies. This review aims to analyze shortly the most common laboratory tests used to assess disease activity in pediatric patients with IBD. In addition to the conventional blood and serum markers that are not specific for gut inflammation, although routinely used, we also reviewed the established fecal markers such as calprotectin, lactoferrin, M2-pyruvate kinase, osteoprotegerin, HMGB1, chitinase 3-like 1, and the promising non-coding microRNA. In conclusion, neither marker is unique to the pediatric IBD. More clinical data are required to assess biomarkers’ full potential for diagnosis, management, and follow-up of pediatric IBD patients.

What is the appropriate cut-off value of CRP to predict endoscopic remission in patients with ulcerative colitis in clinical remission?

PURPOSE

Noninvasive markers for predicting endoscopic remission (ER) in patients with ulcerative colitis (UC) who are in clinical remission (CR) are important for the determination of appropriate treatment modality. C-reactive protein (CRP) is a surrogate marker for assessing disease activity, albeit with a low sensitivity and specificity when the cut-off value is 0.3 or 0.5 mg/dL, which is usually considered normal. The CRP test has been improved, and even fine values within the normal range can be measured. The aim of this study was to determine the appropriate cut-off value of CRP below 0.3 mg/dL for the prediction of ER in UC patients with CR.

METHODS

A total of 132 patients who underwent endoscopic evaluation during CR were retrospectively reviewed. Clinical and endoscopic activity was measured using a simple clinical colitis activity index (SCCAI) and Mayo endoscopic subscore (MES). ER was defined as MES 0 or 1.

RESULTS

In UC patients in CR, the CRP level was significantly lower in ER (0.05, 0.03-2.57) vs. non-ER (0.14, 0.03-2.81) (p < 0.001). The CRP value predicted ER [area under the curve (AUC = 0.710)] with a sensitivity of 71.4% and a specificity of 71.7% at a cut-off value of 0.09 mg/dL. In contrast, the value of normal CRP (< 0.3 mg/dL) did not show sufficient predictive value (sensitivity, 27.3%; and specificity, 90.9%).

CONCLUSIONS

In UC patients in CR, it may be helpful to lower the CRP cut-off value that predict ER other than 0.3 mg/dL, which is usually considered normal.

Myeloid-Derived IL-33 Limits the Severity of Dextran Sulfate Sodium-Induced Colitis

IL-33 is an IL-1 family cytokine that signals through its cognate receptor, ST2, to regulate inflammation. Whether IL-33 serves a pathogenic or protective role during inflammatory bowel disease is controversial. Herein, two different strains of cell-specific conditionally deficient mice were used to compare the role of myeloid- versus intestinal epithelial cell-derived IL-33 during dextran sodium sulfate-induced colitis. Data show that loss of CD11c-restricted IL-33 exacerbated tissue pathology, coinciding with increased tissue Il6 levels and loss of intestinal forkhead box p3⁺ regulatory T cells. Surprisingly, the lack of intestinal epithelial cell-derived IL-33 had no impact on disease severity or tissue recovery. Thus, we show that myeloid-derived IL-33 functionally restrains colitic disease, whereas intestinal epithelial cell-derived IL-33 is dispensable.

Cow and Human Milk-Derived Exosomes Ameliorate Colitis in DSS Murine Model

The aim of this study was to investigate the therapeutic effect of cow and human milk derived exosomes (MDEs) on colitis. We used gavage administration of fluorescent labeled MDEs to track their localization patterns in vivo and studied their therapeutic effect on colitis in a dextran sulfate sodium (DSS)-induced colitis model. MDEs attenuated the severity of colitis induced by DSS and statistically reduced the histopathological scoring grade and shortening of the colon. Likewise, treatment with MDEs reduced the expression of interleukin 6 and tumor necrosis factor-α. Moreover, miRNAs highly expressed in milk, such as miRNA-320, 375, and Let-7, were found to be more abundant in the colon of MDE-treated mice compared with untreated mice; contrastingly, the expression of their target genes, mainly DNA methyltransferase 1 (DNMT1) and DNMT3 were downregulated. Furthermore, the level of TGF-β was upregulated in the colon of MDE-treated mice. We demonstrated that MDEs have a therapeutic and anti-inflammatory effect on colitis, involving several complementary pathways in its mechanism of action. The therapeutic effects of MDEs might have implications for the possible addition of MDEs as a nutrient in enteral nutrition formulas for patients with inflammatory bowel disease.

Serum Interleukin-6 and -8 as Predictors of Response to Vedolizumab in Inflammatory Bowel Diseases

Vedolizumab, a monoclonal antibody directed against integrin α4β7, is an effective treatment for inflammatory bowel diseases. However, a significant number of patients do not achieve steroid-free clinical remission in the first year of treatment. An early identification of these patients is one of the most important challenges for clinicians and offers the possibility of therapeutic optimization in order to personalize biological therapy. The aim of our study was to test the prediction ability of interleukin (IL)-6 and -8 of clinical response after 12 months of therapy with vedolizumab (T2). We performed a prospective, multicentre study in patients affected by inflammatory bowel disease by analysing cytokines level before starting vedolizumab (T0) and after 10 weeks of therapy (T1). In the overall cohort (n = 54), IL-8 decrease > 2.6 pg/mL in the first 10 weeks of therapy was able to predict clinical response (area under the curve (AUC) = 0.70, sensitivity = 66%, specificity = 75%, p = 0.010), negative C-reactive protein (CRP) (AUC = 0.71, sensitivity = 64%, specificity = 80%, p = 0.009) and calprotectin < 250 mg/kg (AUC = 0.69, sensitivity = 64%, specificity = 78%, p = 0.030) after 44 weeks of therapy. In patients with ulcerative colitis (n = 40), baseline IL-8 values > 8.6 pg/mL and a decrease of IL-6 values > 0.4 pg/mL from T0 to T1 were significant and independent predictors of clinical response after 12 months of vedolizumab therapy (odds ratio (OR) = 6.96, 95% CI 1.27–38.22, p = 0.026 and OR = 7.29, 95% CI 1.42–37.50, p = 0.017, respectively). In patients with Crohn’s disease (n = 14), baseline IL-8 values > 8.6 pg/mL and baseline IL-6 values > 1.6 pg/mL allowed the identification of patients achieving negative CRP at T2 (AUC = 0.75, sensitivity = 74%, specificity = 76%, p < 0.001) and patients with faecal calprotectin values < 250 mg/kg at T2 (AUC = 0.71, sensitivity = 78%, specificity = 63%, p = 0.004). In conclusion, our study highlights a potential clinical role of serum cytokine levels for the prediction of clinical and biochemical steroid-free response in patients treated with vedolizumab.

Risk of acute arterial events associated with treatment of inflammatory bowel diseases: nationwide French cohort study

OBJECTIVE

Patients with IBD are at increased risk of acute arterial events. Antitumour necrosis factor (TNF) agents and thiopurines may, via their anti-inflammatory properties, lower the risk of acute arterial events. The aim of this study was to assess the impact of thiopurines and anti-TNFs on the risk of acute arterial events in patients with IBD.

DESIGN

Patients aged 18 years or older and affiliated to the French national health insurance with a diagnosis of IBD were followed up from 1 April 2010 until 31 December 2014. The risks of acute arterial events (including ischaemic heart disease, cerebrovascular disease and peripheral artery disease) were compared between thiopurines and anti-TNFs exposed and unexposed patients with marginal structural Cox proportional hazard models adjusting for baseline and time-varying demographics, medications, traditional cardiovascular risk factors, comorbidities and IBD disease activity.

RESULTS

Among 177 827 patients with IBD (96 111 (54%) women, mean age at cohort entry 46.2 years (SD 16.3), 90 205 (50.7%) with Crohn's disease (CD)), 4145 incident acute arterial events occurred (incidence rates: 5.4 per 1000 person-years). Compared with unexposed patients, exposure to anti-TNFs (HR 0.79, 95% CI 0.66 to 0.95), but not to thiopurines (HR 0.93, 95% CI 0.82 to 1.05), was associated with a decreased risk of acute arterial events. The magnitude in risk reduction was highest in men with CD exposed to anti-TNFs (HR 0.54, 95% CI 0.40 to 0.72).

CONCLUSION

Exposure to anti-TNFs is associated with a decreased risk of acute arterial events in patients with IBD, particularly in men with CD.

Inflammation, but Not the Underlying Disease or Its Location, Predicts Oral Iron Absorption Capacity in Patients With Inflammatory Bowel Disease

BACKGROUND AND AIMS

Anaemia is common in patients with inflammatory bowel disease [IBD], its two main aetiologies being iron deficiency anaemia [IDA] and anaemia of chronic inflammation [ACI]. Impaired intestinal iron absorption due to inflammatory cytokines is thought to play a role in ACI. We undertook for the first time a controlled prospective study investigating effects of differing underlying diseases, disease locations, and types of iron deficiency or anaemia on oral iron absorption in adult IBD patients with and without inflammation.

METHODS

This study was a comparative, single-centred open clinical trial in adults with IBD [n = 73] and healthy controls [n = 22]. Baseline parameters included blood count, iron status [ferritin, transferrin, transferrin saturation, soluble transferrin receptor, hepcidin, serum iron], high-sensitivity C-reactive protein [hsCRP] and interleukin-6. Iron absorption was tested using one oral, enteric-coated capsule containing 567.7 mg iron[II]-glycine-sulphate complex. Serum iron was determined 60/90/120/180/240 min after ingestion.

RESULTS

Iron absorption capacity was shown to be influenced by inflammation and anaemia or iron deficiency [ID] type but not by underlying disease type or localisation. The ACI group showed a significantly lower iron absorption capacity than all others. Whereas hsCRP levels [-0.387, p < 0.001], IL-6 [-0.331, p = 0.006], ferritin [-0.531, p < 0.001], and serum hepcidin [-0.353, p = 0.003] correlated negatively with serum iron change at 2 h, transferrin showed a positive correlation at the same time point [0.379, p < 0.001].

CONCLUSIONS

Underlying disease type and localisation appear to have little effect on iron absorption capacity, whereas lack of response to oral iron correlates well with serum markers of inflammation. Iron absorption capacity is thus significantly reduced in the presence of inflammation.

INTERACTIONS AMONG INTERLEUKIN-6, C-REACTIVE PROTEIN AND INTERLEUKIN-6 (-174) G/C POLYMORPHISM IN THE PATHOGENESIS OF CROHN'S DISEASE AND ULCERATIVE COLITIS

Inflammatory bowel diseases are multifactorial disorders the clinical manifestation of which depends on the interaction among immune response, genetic and environmental factors. There is growing evidence that cytokines and gene polymorphisms have an important role in disease pathogenesis in various populations although molecular mechanism of their signaling and interactions is not fully understood yet. The present study aimed at exploring the effects of interleukin-6, C-reactive protein and interleukin-6 rs1800795 polymorphism on the development of Crohn’s disease, ulcerative colitis and inflammatory bowel diseases overall and at determining differences between inflammatory bowel disease patients and healthy controls. A total of 132 inflammatory bowel disease patients and 71 healthy blood donors were investigated. In order to assess the clinical relevance of interleukin-6 and C-reactive protein serum concentration and interleukin-6 rs1800795 single nucleotide polymorphism in patients with Crohn’s disease and ulcerative colitis, we performed a cross-sectional, case-control study. Quantitative assessment of serum interleukin-6 and C-reactive protein was performed with solid-phase, enzyme-labeled, chemiluminescent sequential immunometric and immunoturbidimetric assay, respectively. A real-time fluorescence resonance energy transfer-based method on a LightCyclerTM PCR 1.2 was used for genotyping of IL-6 rs1800795 polymorphism. Both interleukin-6 and C-reactive protein serum levels were elevated in Crohn’s disease and ulcerative colitis patients. Positive correlations were observed between C-reactive protein and interleukin-6 serum concentration and ulcerative colitis activity index as measured by modified Truelove-Witt’s severity index scale. C-reactive protein serum level was higher in Crohn’s disease patients without intestinal resection than in Crohn’s disease patients with prior intestinal resection. In ulcerative colitis patients, interleukin-6 and C-reactive protein serum levels were statistically significantly higher in CC interleukin-6 genotype in comparison to GG+GC genotype. Analysis of the promoter region of the interleukin-6 rs1800795 gene polymorphism showed no statistically significant difference in allele frequency either between inflammatory bowel disease patients and healthy controls or between the two inflammatory bowel disease phenotypes and healthy controls. Associations presented in this study give a potentially important insight into the role of interleukin-6 and C-reactive protein signaling and interleukin-6 polymorphism in the pathogenesis of Crohn’s disease and ulcerative colitis disease.

Assessment of serum cytokines predicts clinical and endoscopic outcomes to vedolizumab in ulcerative colitis patients

AIMS

Vedolizumab (VDZ) prevents migration of activated leucocytes into inflamed mucosa. This study aimed to assess the patterns of serum cytokines in ulcerative colitis (UC) patients at baseline and during VDZ treatment, and to investigate their association with mucosal healing and clinical remission.

METHODS

We enrolled consecutive UC patients eligible for treatment with VDZ. A panel of serum cytokines were measured by fluorescence assay at weeks 0, 6 and 22. Colonoscopy was performed at baseline and week 54, to evaluate mucosal healing. The time trends of serum cytokines were analysed by log-linear mixed effect models, and their prognostic accuracy was evaluated by logistic regression.

RESULTS

Out of 27 patients included in the analysis, at week 54 mucosal healing was achieved in 12 (44%) and clinical remission in 17 (63%). Mucosal healing was associated with higher interleukin (IL)-8 values at baseline and with significant decrease in IL-6 and IL-8 levels over the first 6 weeks. A significant reduction of IL-6 and IL-8 levels over the first 6 weeks of treatment was associated also with clinical remission. Logistic models including, among the predictors, IL-6 and IL-8 at baseline and their changes over the first 6 weeks of treatment had 83% sensitivity and 87% specificity to predict mucosal healing, and 82% sensitivity and 90% specificity to predict clinical remission.

CONCLUSION

In UC patients, the serum patterns of IL-6 and IL-8 at baseline and over the first 6 weeks of treatment with VDZ could be useful to predict therapeutic outcome.

Increased risk of idiopathic pulmonary fibrosis in inflammatory bowel disease: A nationwide study

BACKGROUND AND AIM

The relationship between inflammatory bowel disease (IBD) and idiopathic pulmonary fibrosis (IPF) remains unclear. We evaluated the risk for developing IPF in patients with IBD using a nationwide population-based study.

METHODS

Using claims data from the National Health Insurance service in Korea, patients with IBD, including Crohn's disease (CD) and ulcerative colitis (UC), were identified through both the 10th revision of the International Statistical Classification of Diseases and Related Health Problems and rare and intractable disease program codes from January 2010 to December 2013. We compared 38 921 IBD patients with age-matched and sex-matched individuals without IBD in a ratio of 1:3. Patients with newly diagnosed IPF were identified by both the 10th revision of the International Statistical Classification of Diseases and Related Health Problems and rare and intractable disease registration codes.

RESULTS

During a mean 4.9-year follow-up, the incidence of IPF in patients with IBD was 33.21 per 100 000 person-years. The overall risk of IPF was significantly higher in IBD patients than in non-IBD controls (hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.20-2.20; P = 0.003). In patients with CD, the incidence (per 100 000 person-years) of IPF was 26.04; in controls, the incidence was 9.15 (HR, 2.89; 95% CI, 1.46-5.72; P = 0.002). The incidence of IPF in patients with UC tended to be higher than in controls (36.66 vs 26.54 per 100 000 person-years; 95% CI, 0.99-1.99; HR, 1.41; P = 0.066). The risk of developing IPF in patients with IBD was higher in male patients than in female patients (P = 0.093 in CD; P = 0.147 in UC by interaction analysis).

CONCLUSIONS

Patients with IBD, especially CD, have an increased risk of developing IPF.

A panoramic review of IL-6: Structure, pathophysiological roles and inhibitors

Interleukin-6 (IL-6) is a pleiotropic pro-inflammatory cytokine. Its deregulation is associated with chronic inflammation, and multifactorial auto-immune disorders. It mediates its biological roles through a hexameric complex composed of IL-6 itself, its receptor IL-6R, and glycoprotein 130 (IL-6/IL-6R/gp130). This complex, in turn, activates different signaling mechanisms (classical and trans-signaling) to execute various biochemical functions. The trans-signaling mechanism activates various pathological routes, like JAK/STAT3, Ras/MAPK, PI3K-PKB/Akt, and regulation of CD4+ T cells and VEGF levels, which cause cancer, multiple sclerosis, rheumatoid arthritis, anemia, inflammatory bowel disease, Crohn's disease, and Alzheimer's disease. Involvement of IL-6 in pathophysiology of these complex diseases makes it an important target for the treatment of these diseases. Though some anti-IL-6 monoclonal antibodies are being used clinically, but their high cost, only parenteral administration, and possibility of immunogenicity have limited their use, and warranted the development of novel small non-peptide molecules as IL-6 inhibitors. In the present report, all molecules reported in literature as IL-6 inhibitors have been classified as IL-6 production, IL-6R, and IL-6 signaling inhibitors. Reports available till date are critically studied to identify important and salient structural features common in these molecules. These analyses would assist medicinal chemists to design novel and potent IL-6 production and signaling inhibitors, through knowledge- and/or computer-based approaches, for the treatment of complex multifactorial diseases.

Effect of Loureirin B on Crohn's disease rat model induced by TNBS via IL-6/STAT3/NF-κB signaling pathway

Background

Crohn’s disease (CD) is a chronic relapsing form of inflammatory bowel disease, seriously threatening human beings health. However, the pathogenesis of CD is still unclear and there is no specific effective drug for treatment of CD. Resina Donis (RD) obtained from Dracaena cochinchinensis (Lour.) S. C. Chen (Liliaceae), has been used for the treatment of CD clinically. Loureirin B (LB) is one of the most important chemical compositions and physiologically active ingredients of resina draconis. It has the molecular structure propan-1-one, 1-(4-hydroxyphenyl)-3-(2,4,6-trimethoxyphenyl)-1-(4-hydroxyphenyl)-3-(2,4,6-trimethoxyphenyl) propan-1-one. The aim of this study was to investigate the effect of LB on CD and explore the underlying mechanisms.

Methods and results

In this study, the result demonstrated that LB prolonged the survival time of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rats and alleviated colonic damage in a dose dependent manner. Besides, LB remarkably ameliorated TNBS-induced inflammatory response via regulation of cytokines in the colonic tissues. Moreover, LB could reverse the established fibrosis and impede the accumulation infiltration, and improve the apoptosis induced by TNBS in a dose dependent manner. Further, LB dramatically suppressed TNBS-induced the activation of IL-6/STAT3/NF-κB signaling pathway.

Conclusions

These findings suggested that LB could be beneficial regarding ameliorating TNBS-induced CD, which may represent a novel approach to treat CD and provide an alternative choice for disorders associated with CD.

A Comprehensive Review and Update on the Pathogenesis of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic and life-threating inflammatory disease of gastroenteric tissue characterized by episodes of intestinal inflammation. The pathogenesis of IBD is complex. Recent studies have greatly improved our knowledge of the pathophysiology of IBD, leading to great advances in the treatment as well as diagnosis of IBD. In this review, we have systemically reviewed the pathogenesis of IBD and highlighted recent advances in host genetic factors, gut microbiota, and environmental factors and, especially, in abnormal innate and adaptive immune responses and their interactions, which may hold the keys to identify novel predictive or prognostic biomarkers and develop new therapies.

Evaluation of cytokine levels as putative biomarkers to predict the pharmacological response to biologic therapy in inflammatory bowel diseases

Cytokines play a central role in the pathogenesis of inflammatory bowel diseases. For this reason, the vast majority of biological therapies are aimed to block pro-inflammatory cytokines or their receptors. Although these drugs have modified the course of the disease due to their efficacy, a high rate of non-response or loss of response over time is still an important issue for clinicians. In this perspective, many studies have been conducted in recent years to individuate a reliable biomarker of therapeutic response. In this review, we discuss the role of cytokines involved in the pathogenesis and in the therapy of inflammatory bowel diseases, and their putative use as pharmacological biomarkers of therapy responsiveness.

Paradoxical role of Breg-inducing cytokines in autoimmune diseases

Regulatory B cells (Breg) are crucial immunoregulators that maintain peripheral tolerance and suppress inflammatory autoimmune responses. In recent years, our understanding on the nature and mechanism of action of Bregs has revealed the important role of cytokines in promoting the regulatory properties of this unique B cell subset, both in animal and human models. In this review, we compiled the cytokines that have been reported by multiple studies to induce the expansion of Breg. The Breg-inducing cytokines which are currently known include IL-21, IL-6, IL1β, IFNα, IL-33, IL-35, BAFF and APRIL. As cytokines are also known to play a pivotal role in the pathogenesis of autoimmune diseases, in parallel we reviewed the pattern of expression of the Breg-inducing cytokines in Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), Inflammatory Bowel Diseases (IBD) and Multiple Sclerosis (MS). We show here that Breg-inducing cytokines are commonly implicated in these inflammatory diseases where they typically have a higher expression than in healthy individuals, suggesting their paradoxical nature. Interestingly, despite the general overexpression of Breg-inducing cytokines, it is known that Breg cells are often numerically or functionally impaired in various autoimmune conditions. Considering these alterations, we explored the possible parameters that may influence the function of Breg-inducing cytokines in exhibiting either their regulatory or pro-inflammatory properties in the context of autoimmune conditions.

Evaluating tofacitinib citrate in the treatment of moderate-to-severe active ulcerative colitis: design, development and positioning of therapy

The etiology of ulcerative colitis (UC) is complex and involves a host of genetic, epigenetic and environmental factors. Over the last thirty years, signaling pathways like the Janus kinase (JAK) signaling pathway have been implicated in its pathogenesis. Pharmacologic blockade of this pathway is available through several small molecule inhibitors, including tofacitinib. Tofacitinib is an orally administered pan-JAK inhibitor that was first approved by the Food and Drug Administration (FDA) for use in rheumatologic disorders such as rheumatoid arthritis and psoriatic arthritis. The FDA approved its use in moderate-to-severe active ulcerative colitis in 2018. The aim of this review will be to discuss the role of tofacitinib in ulcerative colitis. We will discuss the role of JAK-STAT signaling, clinical data available for tofacitinib, and the safety profile for this therapy. Tofacitinib's place in the UC management algorithm is currently being debated. This effective oral therapy is poised to be a mainstay of UC therapeutics. This review will highlight the key clinical features and detail the UC experience to date.

Increased end-stage renal disease risk in patients with inflammatory bowel disease: A nationwide population-based study

AIM

To estimate the risk of end-stage renal disease (ESRD) in patients with inflammatory bowel disease (IBD).

METHODS

From January 2010 to December 2013, patients with Crohn’s disease (CD) and ulcerative colitis (UC) were identified, based on both the International Classification of Diseases, 10^th revision (ICD-10) and the rare, intractable disease registration program codes from the National Health Insurance (NHI) database in South Korea. We compared 38812 patients with IBD to age- and sex-matched non-IBD controls with a ratio of 1:3. Patients newly diagnosed with ESRD were identified with the ICD-10 code.

RESULTS

During a mean follow-up of 4.9 years, ESRD was detected in 79 (0.2%) patients with IBD and 166 (0.1%) controls. The incidence of ESRD in patients with IBD was 0.42 per 1000 person-years. Patients with IBD had a significantly higher risk of ESRD than controls [adjusted hazard ratio (HR) = 3.03; 95% confidence interval (CI): 1.77-5.20; P < 0.001]. The incidences (per 1000 person-years) of ESRD were 0.51 in patients with CD and 0.13 in controls, respectively (adjusted HR = 6.33; 95%CI: 2.75-14.56; P < 0.001). In contrast, the incidence of ESRD was similar between the UC and control groups (0.37 vs 0.37 per 1000 person-years; adjusted HR = 2.01; 95%CI: 0.90-4.51; P = 0.089).

CONCLUSION

The risk of ESRD was elevated in patients with CD, but not UC. Patients with CD should be monitored carefully for signs of renal insufficiency.

Disruption of FOXP3-EZH2 Interaction Represents a Pathobiological Mechanism in Intestinal Inflammation

Background & Aims

Forkhead box protein 3 (FOXP3)+ regulatory T cell (Treg) dysfunction is associated with autoimmune diseases; however, the mechanisms responsible for inflammatory bowel disease pathophysiology are poorly understood. Here, we tested the hypothesis that a physical interaction between transcription factor FOXP3 and the epigenetic enzyme enhancer of zeste homolog 2 (EZH2) is essential for gene co-repressive function.

Methods

Human FOXP3 mutations clinically relevant to intestinal inflammation were generated by site-directed mutagenesis. T lymphocytes were isolated from mice, human blood, and lamina propria of Crohn's disease (CD) patients and non-CD controls. We performed proximity ligation or a co-immunoprecipitation assay in FOXP3-mutant+, interleukin 6 (IL6)-treated or CD-CD4+ T cells to assess FOXP3-EZH2 protein interaction. We studied IL2 promoter activity and chromatin state of the interferon γ locus via luciferase reporter and chromatin-immunoprecipitation assays, respectively, in cells expressing FOXP3 mutants.

Results

EZH2 binding was abrogated by inflammatory bowel disease-associated FOXP3 cysteine 232 (C232) mutation. The C232 mutant showed impaired repression of IL2 and diminished EZH2-mediated trimethylation of histone 3 at lysine 27 on interferon γ, indicative of compromised Treg physiologic function. Generalizing this mechanism, IL6 impaired FOXP3-EZH2 interaction. IL6-induced effects were reversed by Janus kinase 1/2 inhibition. In lamina propria-derived CD4+T cells from CD patients, we observed decreased FOXP3-EZH2 interaction.

Conclusions

FOXP3-C232 mutation disrupts EZH2 recruitment and gene co-repressive function. The proinflammatory cytokine IL6 abrogates FOXP3-EZH2 interaction. Studies in lesion-derived CD4+ T cells have shown that reduced FOXP3-EZH2 interaction is a molecular feature of CD patients. Destabilized FOXP3-EZH2 protein interaction via diverse mechanisms and consequent Treg abnormality may drive gastrointestinal inflammation.

Increased risk of acute arterial events in young patients and severely active IBD: a nationwide French cohort study

OBJECTIVE

Magnitude and independent drivers of the risk of acute arterial events in IBD are still unclear. We addressed this question in patients with IBD compared with the general population at a nationwide level.

DESIGN

Using the French National Hospital Discharge Database from 2008 to 2013, all patients aged 15 years or older and diagnosed with IBD were identified and followed up until 31 December 2013. The rates of incident acute arterial events were calculated and the impact of time with active disease (period around hospitalisation for IBD flare or IBD-related surgery) on the risk was assessed by Cox regression adjusted for traditional cardiovascular risk factors.

RESULTS

Among 210 162 individuals with IBD (Crohn's disease (CD), n=97 708; UC, n=112 454), 5554 incident acute arterial events were identified. Both patients with CD and UC had a statistically significant overall increased risk of acute arterial events (standardised incidence ratio (SIR) 1.35; 95% CI 1.30 to 1.41 and SIR 1.10; 95 CI 1.06 to 1.13, respectively). The highest risk was observed in patients under the age of 55 years, both in CD and UC. The 3-month periods before and after IBD-related hospitalisation were associated with an increased risk of acute arterial events in both CD and UC (HR 1.74; 95 CI 1.44 to 2.09 and 1.87; 95% CI 1.58 to 2.22, respectively).

CONCLUSION

Patients with IBD are at increased risk of acute arterial events, with the highest risk in young patients. Disease activity may also have an independent impact on the risk.

Pien Tze Huang ameliorates DSS‑induced colonic inflammation in a mouse colitis model through inhibition of the IL‑6/STAT3 pathway

Interleukin‑6 (IL‑6)/signal transducer and activator of transcription 3 (STAT3) pathway plays essential roles in the development of inflammatory diseases including ulcerative colitis (UC). Therefore, suppression of IL‑6/STAT3 signaling provides a promising therapeutic strategy in UC. Pien Tze Huang (PZH), a well‑known traditional Chinese formula, has been used in China and Southeast Asia for centuries as a folk remedy for various inflammatory diseases. However, the molecular mechanisms of its anti‑inflammatory effects remain to be elucidated. In the present study, we generated a mouse colitis model by using dextran sulfate sodium (DSS) and evaluated the therapeutic efficacy of PZH against UC by observing the clinical manifestations. We found that PZH obviously alleviated DSS‑induced colitis symptoms, including body weight loss, rectal bleeding and stool consistency. In addition, administration of PZH profoundly prevented DSS‑induced colon shortening, and ameliorated colonic histopathological changes such as mucosal ulceration, infiltration of inflammatory cells, crypt distortion and hyperplastic epithelium. Moreover, PZH markedly inhibited the serum level of the inflammatory biomarker serum amylase A (SAA) in UC mice. Furthermore, PZH treatment significantly inhibited DSS‑induced expression of IL‑6 in colon tissues. Finally, the increased phosphorylation level of STAT3, induced either by DSS in experimental mice or by IL‑6 in the differentiated human colorectal carcinoma cells, was significantly suppressed by PZH. These results suggest that the inhibition of IL‑6/STAT3 signaling is a potential mechanism by which PZH is used in the treatment of UC.

Immunotherapy in inflammatory bowel disease: Novel and emerging treatments

Inflammatory bowel disease (IBD) is a chronic disabling inflammatory process that affects young individuals, with growing incidence. The etiopathogenesis of IBD remains poorly understood. A combination of genetic and environmental factors triggers an inadequate immune response against the commensal intestinal flora in IBD patients. Thus, a better understanding of the immunological mechanisms involved in IBD pathogenesis is central to the development of new therapeutic options.

Current pharmacological treatments used in clinical practice like thiopurines or anti-TNF are effective but can produce significant side effects and their efficacy may diminish over time. In fact, up to one third of the patients do not have a satisfactory response to these therapies. Consequently, the search for new therapeutic strategies targeting alternative immunological pathways has intensified. Several new oral and parenteral substances are in the pipeline for IBD.

In this review we discuss novel therapies targeting alternative pro-inflammatory pathways like IL-12/23 axis, IL-6 pathway or Janus Kinase inhibitors; as well as others modulating anti-inflammatory signalling pathways like transforming growth factor-β1 (TGF-β1). We also highlight new emerging therapies targeting the adhesion and migration of leukocytes into the inflamed intestinal mucosa by blocking selectively different subunits of α₄β₇ integrins or binding alternative adhesion molecules like MAdCAM-1. Drugs reducing the circulating lymphocytes by sequestering them in secondary lymphoid organs (sphingosine-1-phosphate (S1P) receptor modulators) are also discussed. Finally, the latest advances in cell therapies using mesenchymal stem cells or engineered T regs are reviewed. In addition, we provide an update on the current status in clinical trials of these new immune-regulating therapies that open a new era in the treatment of IBD.

Association of IL -6 -174 G>C polymorphism with the risk of SLE among south Indians: evidence from case-control study and meta-analysis

Cytokines play a direct role in disease pathogenesis of systemic lupus erythematosus (SLE). Elevated levels of serum IL-6 are well documented with the disease activity and anti-dsDNA antibodies in SLE. The 5' promoter region of the IL-6 gene has been shown to play a significant role in the regulation of gene expression. In view of this, the current study aimed to investigate the possible association of 5' promoter polymorphisms G-597A (rs1800797), G-572C (rs1800796) and G-174C (rs1800795) with the risk of SLE. Analysis of 468 subjects (202 SLE patients and 266 controls) showed a significant association of the -174 G/C variant with the SLE risk in both dominant and recessive model (odds ratio (OR) 3.20, 95% confidence interval (CI) 1.18-8.69, P = 0.020 and OR 2.02, 95% CI 1.35-3.02, P = 0.0005), respectively. The 'G allele of the -174 loci (OR 1.97, 95% CI 1.39-2.78, P = 0.00012) has shown significant distribution between the cases and controls. The haplotype analysis revealed that AGG haplotype carriers are more frequent in cases than controls and found a significant positive association (OR 1.394, 95% CI 1.07-7.12, P = 0.028) with SLE. In addition, we also undertook a meta-analysis on 13 study groups for -174 G/C, comprising a total of 1585 cases and 1690 controls. The pooled OR also suggested a significant association of -174 G/C with SLE (OR 1.36, 95% CI 1.22-1.53, P < 0.05). In conclusion, the presence of the G allele at the IL-6 polymorphic promoter loci -174 is a risk factor and might influence SLE disease and pathogenesis. Meta-analysis has also suggested the overall correlation between -174 G/C polymorphism and SLE risk.

Fibroblast Growth Factor 21 Deficiency Attenuates Experimental Colitis-Induced Adipose Tissue Lipolysis

Aims

Nutrient deficiencies are common in patients with inflammatory bowel disease (IBD). Adipose tissue plays a critical role in regulating energy balance. Fibroblast growth factor 21 (FGF21) is an important endocrine metabolic regulator with emerging beneficial roles in lipid homeostasis. We investigated the impact of FGF21 in experimental colitis-induced epididymal white adipose tissue (eWAT) lipolysis.

Methods

Mice were given 2.5% dextran sulfate sodium (DSS) ad libitum for 7 days to induce colitis. The role of FGF21 was investigated using antibody neutralization or knockout (KO) mice. Lipolysis index and adipose lipolytic enzymes were determined. In addition, 3T3-L1 cells were pretreated with IL-6, followed by recombinant human FGF21 (rhFGF21) treatment; lipolysis was assessed.

Results

DSS markedly decreased eWAT/body weight ratio and increased serum concentrations of free fatty acid (FFA) and glycerol, indicating increased adipose tissue lipolysis. eWAT intracellular lipolytic enzyme expression/activation was significantly increased. These alterations were significantly attenuated in FGF21 KO mice and by circulating FGF21 neutralization. Moreover, DSS treatment markedly increased serum IL-6 and FGF21 levels. IL-6 pretreatment was necessary for the stimulatory effect of FGF21 on adipose lipolysis in 3T3-L1 cells.

Conclusions

Our results demonstrate that experimental colitis induces eWAT lipolysis via an IL-6/FGF21-mediated signaling pathway.

Novel Targeted Therapies for Inflammatory Bowel Disease

Our growing understanding of the immunopathogenesis of inflammatory bowel disease (IBD) has opened new avenues for developing targeted therapies. These advances in treatment options targeting different mechanisms of action offer new hope for personalized management. In this review we highlight emerging novel and easily administered therapeutics that may be viable candidates for the management of IBD, such as antibodies against interleukin 6 (IL-6) and IL-12/23, small molecules including Janus kinase inhibitors, antisense oligonucleotide against SMAD7 mRNA, and inhibitors of leukocyte trafficking to intestinal sites of inflammation (e.g., sphingosine 1-phosphate receptor modulators). We also provide an update on the current status in clinical development of these new classes of therapeutics.

A Review of the Relationship Between Parenteral Nutrition and Metabolic Bone Disease

Metabolic bone disease (MBD) refers to the conditions that produce a diffuse decrease in bone density and strength because of an imbalance between bone resorption and bone formation. MBD can be a potential complication in patients receiving chronic parenteral nutrition (PN) therapy and the management of this condition presents a challenge for many clinicians. The etiology of PN-associated MBD is poorly understood, but traditional risk factors can include malnutrition, vitamin and mineral deficiencies, toxic contaminants in the PN solution, concomitant medications, and presence of certain disease states. Although additional studies are warranted to further elucidate the development and management of this condition, the following review discusses some of the important factors that may play a role in the genesis of PN-associated MBD and evaluates some potential strategies for the diagnosis and treatment of this complication.