Background: Ulcerative colitis [UC] is a common chronic inflammatory bowel disease without curative treatment. Methods: We conducted gene set enrichment analysis to explore potential therapeutic agents for UC. Human colon tissue samples were collected to test H3 acetylation in UC. Both in vivo and in vitro colitis models were constructed to verify the role and mechanism of H3 acetylation modification in UC. Intestine-specific vitamin D receptor [VDR](-/-) mice and VD [vitamin D]-deficient diet-fed mice were used to explore downstream molecular mechanisms accordingly. Results: According to the Connectivity Map database, MS-275 [class I histone deacetylase inhibitor] was the top-ranked agent, indicating the potential importance of histone acetylation in the pathogenesis of UC. We then found that histone H3 acetylation was significantly lower in the colon epithelium of UC patients and negatively associated with disease severity. MS-275 treatment inhibited histone H3 deacetylation, subsequently attenuating nuclear factor kappa B [NF-kappa B]-induced inflammation, reducing cellular apoptosis, maintaining epithelial barrier function, and thereby reducing colitis activity in a mouse model of colitis. We also identified VDR as be a downstream effector of MS-275. The curative effect of MS-275 on colitis was abolished in VDR-/- mice and in VD-deficient diet-fed mice and VDR directly targeted p65. In UC patients, histone H3 acetylation, VDR and zonulin-1 expression showed similar downregulation patterns and were negatively associated with disease severity. Conclusions: We demonstrate that MS-275 inhibits histone deacetylation and alleviates colitis by ameliorating inflammation, reducing apoptosis, and maintaining intestinal epithelial barrier via VDR, providing new strategies for UC treatment.
Introduction: Using therapeutic drug monitoring [TDM] in adult patients with inflammatory bowel disease [IBD] remains controversial. We conducted a systematic review and meta-analysis to answer four clinical PICO [Population, Intervention, Comparator, Outcome] questions. Methods: We searched MEDLINE, Embase, Web of Science, and Cochrane Central from inception to June 30, 2019. Remission was defined by the manuscripts' definitions of clinical remission. Data were analysed using RevMan 5.3. Quality of evidence was assessed with GRADE methodology. Results: We identified and screened 3365 abstracts and 11 articles. PICO 1 Reactive vs NoTDM: six studies pooled showed 57.1% [257/450] failed to achieve remission following reactive TDM vs 44.7% [268/600] in the no TDM group (risk ratio [RR]: 1.14; 95% confidence interval [CI] 0.88-1.47). PICO 2 Proactive vs no TDM: five studies pooled showed 19.5% [75/384] failed to maintain remission in the proactive TDM group vs 33.4% [248/742] in the noTDM group [RR: 0.60; 95% CI 0.35-1.04]. PICO 3 Proactive vs Reactive TDM: two retrospective studies pooled showed 14.2% [26/183] failure to maintain remission in the proactive TDM group and 64.7% [119/184] in the reactive TDM group [RR: 0.22; 95% CI 0.15-0.32]. PICO 4 TDM [proactive/reactive] vs NoTDM: we pooled 10 studies showing 39.7% [332/837] failed to achieve remission in the TDM [proactive/reactive] cohort vs 40.3% [428/1063] in the no TDM cohort [RR: 0.94; 95% CI 0.77-1.14]. Overall, the quality of evidence in each PICO was very low when using GRADE. Conclusions: This meta-analysis shows that data supporting use of TDM in adults are limited and of very low quality. Further well-designed randomized controlled trials are needed to determine the place of TDM in clinical practice.
Background: Several studies have reported that ulcerative colitis [UC] patients with endoscopic mucosal healing may still have histological inflammation. We investigated the relationship between mucosal healing defined by modified PICaSSO [Paddington International Virtual ChromoendoScopy ScOre], Mayo Endoscopic Score [MES] and probe-based confocal laser endomicroscopy [pCLE] with histological indices in UC. Methods: A prospective study enrolling 82 UC patients [male 66%] was conducted. High-definition colonoscopy was performed to evaluate the activity of the disease with MES assessed with High-Definition MES [HD-MES] and modified PICaSSO and targeted biopsies were taken; pCLE was then performed. Receiver operating characteristic [ROC] curves were plotted to determine the best thresholds for modified PICaSSO and pCLE scores that predicted histological healing according to the Robarts Histopathology Index [RHI] and ECAP 'Extension, Chronicity, Activity, Plus' histology score. Results: A modified PICaSSO of <= 4 predicted histological healing at RHI <= 3, with sensitivity, specificity, accuracy and area under the ROC curve [AUROC] of 89.8%, 95.7%, 91.5% and 95.9% respectively. The sensitivity, specificity, accuracy and AUROC of HD-MES to predict histological healing by RHI were 81.4%, 95.7%, 85.4% and 92.1%, respectively. A pCLE <= 10 predicted histological healing with sensitivity of 94.9%, specificity of 91.3%, accuracy of 93.9% and AUROC of 96.5%. An ECAP of <= 10 was predicted by modified PICaSSO <= 4 with accuracy of 91.5% and AUROC of 95.9%. Conclusion: Histological healing by RHI and ECAP is accurately predicted by HD-MES and modified virtual electronic chromoendoscopy PICaSSO, endoscopic score; and the use of pCLE did not improve the accuracy any further.
Background and Aims: Poor knowledge of inflammatory bowel disease [IBD] in pregnancy underlies unwarranted voluntary childlessness [VC], and risks poorer obstetric outcomes and adverse fetal outcomes. IBD is increasing worldwide but education on IBD issues might be heterogeneous based on cultural differences and variations in models of care. Methods: Consecutive female IBD subjects aged 18-45 years were prospectively recruited from two dedicated IBD-pregnancy clinics, two multidisciplinary IBD clinics and nine general gastroenterology clinics. Subjects completed the validated CCPKnow [score 0-17] with questions on demographics, medical history and pregnancy knowledge. The primary outcome was knowledge per clinic-type and per geographical region. Results: Surveys were completed by 717 subjects from 13 hospitals across ten countries. Dedicated IBD-pregnancy clinics had the highest knowledge, followed by multidisciplinary IBD clinics then general IBD clinics (median CCPKnow 10.0 [IQR: 8.0-11.0], 8.0 [IQR: 5.0-10.5] and 4.0 [IQR:2.0-6.0]; p < 0.001). Median CCPKnow scores in Western, Asian and Middle Eastern clinics were 9.0, 5.0 and 3.0 respectively [p < 0.001]. Dedicated IBD-pregnancy clinics, IBD support organization membership, childbearing after IBD diagnosis and employment independently predicted greater knowledge. Patient perception of disease severity [r = -0.18, p < 0.01] and consideration of VC [r = -0.89, p = 0.031] negatively correlated with CCPKnow score. The overall VC rate was 15.0% [95% CI: 12.2-18.2]. VC subjects had significantly lower pregnancy-specific IBD knowledge than non-VC subjects (median CCPKnow 4.0 [IQR: 2.0-6.0] and 6.0 [IQR: 3.0-9.0] respectively; p < 0.001). Pregnancy-specific IBD knowledge and dedicated IBD-pregnancy clinic attendance were significant negative predictors of VC. Conclusions: In this large international study we identified predictors of pregnancy-specific IBD knowledge. Dedicated IBD-pregnancy clinics had the greatest IBD-related pregnancy knowledge and lowest VC rates, reflecting the benefits of pre-conception counselling.
Endoscopy is an essential component in the management of inflammatory bowel disease [IBD]. There is a risk of SARS-CoV-2 transmission during endoscopic procedures. The International Organization for the study of IBD [IOIBD] has developed 11 position statements, based on an online survey, that focus on how to prioritise endoscopies in IBD patients during the COVID-19 pandemic, alternative modes for disease monitoring, and ways to triage the high number of postponed endoscopies after the pandemic. We propose to pre-screen patients for suspected or confirmed COVID-19 and test for SARS-CoV-2 before endoscopy if available. High priority endoscopies during pandemic include acute gastrointestinal bleed, acute severe ulcerative colitis, new IBD diagnosis, cholangitis in primary sclerosing cholangitis, and partial bowel obstruction. Alternative modes of monitoring using clinical symptoms, serum inflammatory markers, and faecal calprotectin should be considered during the pandemic. Prioritising access to endoscopy in the post-pandemic period should be guided by control of COVID-19 in the local community and availability of manpower and personal protective equipment. Endoscopy should be considered within 3 months after the pandemic for patients with a past history of dysplasia and endoscopic resection for dysplastic lesion. Endoscopy should be considered 3-6 months after the pandemic for assessment of postoperative recurrence or new biologic initiation. Endoscopy can be postponed until after 6 months of pandemic for routine IBD surveillance and assessment of mucosal healing.
Background: Macrophage-inducible C-type lectin [Mincle] signalling plays a proinflammatory role in different organs such as the brain and liver, but its role in intestinal inflammation, including Crohn's disease [CD], remains unknown. Methods: The characteristics of Mincle signalling expression in CD patients and experimental colitis were examined. The functional role of Mincle signalling in the intestine was addressed in experimental colitis models in vivo by using Mincle knock-out [Mincle-/-] mice. In addition, neutralising anti-Mincle antibody, downstream spleen tyrosine kinase [Syk] inhibitor, and Mincle pharmacological agonist were used to study the Mincle signalling in intestine. Bone marrow-derived macrophages were collected from mice and used to further verify the effect of Mincle signalling in macrophages. Results: This study has shown that Mincle signalling was significantly elevated in active human CD and experimental colitis, and macrophages were the principal leukocyte subset that upregulate Mincle signalling. Mincle deficiency and Syk pharmacological inhibition ameliorated the colitis by reducing induced macrophage pyroptosis, and activation of Mincle with the agonist aggravated the intestinal inflammation. The ex vivo studies demonstrated that activation of Mincle signalling promoted the release of proinflammatory cytokines, whereas its absence restricted release of proinflammatory cytokines from pyroptosis of macrophages. In addition, Mincle/Syk signalling in macrophages could promote the production of chemokines to recruit neutrophils by activating mitogen-activated protein kinase [MAPK] during intestinal inflammation. Conclusions: Mincle signalling promotes intestinal mucosal inflammation by inducing macrophage pyroptosis. Modulation of the Mincle/Syk axis emerges as a potential therapeutic strategy to target inflammation and treat CD.
Background and Aims: Despite the therapeutic promise of stem cell therapy in the treatment of inflammatory bowel diseases [IBD], most donor cell populations have to be obtained via invasive approaches and often remain insufficiently validated. Urine-derived stem cells [USC] were recently shown to have regenerative properties and can be harvested in a safe, low-cost, and noninvasive way. This study aims to evaluate the immunomodulatory effect of USC and their efficacy in the management of IBD. Methods: Human USC were isolated and expanded from the urine of healthy male adult volunteers [n=3, age range 24-30 years]. USC were characterised by cell surface marker expression profile and multipotent differentiation. The in vitro immunomodulatory effect of USC was evaluated by co-culturing with human CD4(+) T cells upon stimulation with phytohaemagglutinin [PHA]. The proliferation of CD4(+) T was measured by fluorescence-activated cell sorting [FACS]. Cytokine array and quantitative real-time polymerase chain reaction [RT-PCR] were applied to examine cytokine levels. In vivo therapeutic value of USC was assessed using a murine colitis model induced by dextran sulphate sodium [DSS] or 2, 4, 6-trinitrobenzene sulphonic acid [MSS]. The immunomodulatory effect of USC and bone marrow-derived mesenchymal stem cells [BMSC] was compared when co-cultured with CD4(+) T cells. The therapeutic efficacy of USC and BMSC on IBD was compared when administered in an acute DSS model in vivo. Results: USC were positivefor mesenchymal stem cell markers but were negative for haematopoietic stem cell markers. These cells differentiated into osteo-, adipo-, and chondrogenic cell lineages. Similar to BMSC, the proliferation of CD4(+) T cells was significantly inhibited when co-cultured with USC, as a consequence of Th1/Th17 immune response inhibition. Systemic administration of USC significantly ameliorated the clinical and histopathological severity of colitis and increased the survival rate in both acute and chronic murine colitis models. Moreover, implantation of USC led to downregulation of the Th1/Th17 immune responses in a PGE(2)-dependent manner. Conclusions: This study demonstrated that implantation of USC reduces inflammation in an IBD rodent model via downregulation of Th1/Th17 immune responses, indicating that USC therapy serves as a potential cell-based therapeutic candidate treatment for IBD.
Background and Aims: Among the >240 genetic loci described to date which confer susceptibility to inflammatory bowel disease, a small subset have been fine-mapped to an individual, non-coding single nucleotide polymorphism [SNP]. To illustrate a model mechanism by which a presumedcausal non-coding SNP can function, we analysed rs1887428, located in the promoter region of the Janus kinase 2 [JAK2] gene. Methods: We utilized comparative affinity purification-mass spectrometry, DNA-protein binding assays, CRISPR/Cas9 genome editing, transcriptome sequencing and methylome quantitative trait locus methods to characterize the role of this SNP. Results: We determined that the risk allele of rs1887428 is bound by the transcription factor [TF] RBPJ, while the protective allele is bound by the homeobox TF CUX1. While rs188748 only has a very modest influence on JAK2 expression, this effect was amplified downstream through the expression of pathway member STAT5B and epigenetic modification of the JAK2 locus. Conclusion: Despite the absence of a consensus TF-binding motif or expression quantitative trait locus, we have used improved methods to characterize a putatively causal SNP to yield insight into inflammatory bowel disease mechanisms.
Background and Aims: Crohn's disease [CD] can involve any part of the gastrointestinal tract. We aimed to characterize the clinical, endoscopic and histological features and treatment outcomes of CD patients with oesophageal involvement. Methods: We collected cases through a retrospective multicentre European Crohn's and Colitis Organisation CONFER [COllaborative Network For Exceptionally Rare case reports] project. Clinical data were recorded in a standardized case report form. Results: A total of 40 patients were reported (22 males, mean [+/- SD, range] age at oesophageal CD diagnosis: 25 [+/- 13.3, 10-71] years and mean time of follow-up: 67 [+/- 68.1, 3-240] months). Oesophageal involvement was established at CD diagnosis in 26 patients [65%] and during follow-up in 14. CD was exclusively located in the oesophagus in two patients. Thirteen patients [32.2%] were asymptomatic at oesophageal disease diagnosis. Oesophageal strictures were present in five patients and fistulizing oesophageal disease in one. Eight patients exhibited granulomas on biopsies. Proton-pump inhibitors [PPIs] were administered in 37 patients [92.5%]. Three patients underwent endoscopic dilatation for symptomatic strictures but none underwent oesophageal-related surgery. Diagnosis in pre-established CD resulted in treatment modifications in 9/14 patients. Clinical remission of oesophageal disease was seen in 33/40 patients [82.5%] after a mean time of 7 [+/- 5.6, 1-18] months. Follow-up endoscopy was performed in 29/40 patients and 26/29 [89.7%] achieved mucosal healing. Conclusion: In this case series the endoscopic and histological characteristics of isolated oesophageal CD were similar to those reported in other sites of involvement. Treatment was primarily conservative, with PPIs administered in the majority of patients and modifications in preexisting inflammatory bowel disease-related therapy occurring in two-thirds of them. Clinical and endoscopic remission was achieved in more than 80% of of the patients.
Background and Aims: Interleukin 6 [IL-6] or its receptor is currently a candidate for targeted biological therapy of inflammatory bowel disease [IBD]. Thus, a comprehensive understanding of the consequences of blocking IL-6 is imperative. We investigated this by evaluating the effects of IL-6 deletion on the spontaneous colitis of IL-10-deficient mice [IL-10(-/-)]. Methods: IL-6/IL-10 double-deficient mice [IL-6(-/-)/IL-10(-/-)] were generated and analysed for intestinal inflammation, general phenotypes and molecular/biochemical changes in the colonic mucosa compared with wild-type and IL-10(-/-) mice. Results: Unexpectedly, the IL-6(-/-)/IL-10(-/-) mice showed more pronounced gut inflammation and earlier disease onset than IL-10(-/-) mice, both locally [colon and small bowel] and systemically [splenomegaly, ulcerative dermatitis, leukocytosis, neutrophilia and monocytosis]. IL-6(-/-)/IL-10(-/-) mice exhibited elevations of multiple cytokines [IL-1 beta, IL-4, IL-12, TNF alpha] and chemokines [MCP-1 and MIG], but not IFN-gamma [Th1], IL-17A and IL-17G [Th17], or IL-22 [Th22]. FOXP3 and TGF-beta, two key factors for regulatory T [Treg] cell differentiation, were significantly down-regulated in the colonic mucosa, but not in the thymus or mesenteric lymph nodes, of IL-6(-/-)/IL-10(-/-) mice. CTLA-4 was diminished while iNOS was up-regulated in the colonic mucosa of IL-6(-/-)/IL-10(-/-) mice. Conclusion: In IL-10(-/-) mice, complete IL-6 blockade significantly aggravates gut inflammation, at least in part by suppressing Treg/CTLA-4 and promoting the IL-1 beta/Th2 pathway. In addition, the double mutant exhibits signs of severe systemic inflammation. Our data define a new function of IL-6 and suggest that caution should be exercised when targeting IL-6 in IBD patients, particularly those with defects in IL-10 signalling.
Background and Aims: Heat shock protein 90 [Hsp90]-targeted therapy has been proposed as a promising strategy for the treatment of ulcerative colitis [UC] and colitis-associated cancer [CAC]. Systemic administration of the Hsp90 inhibitor, 17-AAG, was found to be profoundly protective in preclinical mouse models of inflammatory bowel disease [IBD]. However, the therapeutic potential of 17-AAG is limited by potential side effects associated with its systemic exposure and the modest bioavailability afforded by its oral administration. Methods: To address these issues, we used a versatile single-step surface-functionalizing technique to prepare a 17-AAG oral delivery system using PLGA/PLA-PEG-FA nanoparticles [NP-PEG-FA/17-AAG]. Results: NP-PEG-FA could be efficiently taken up by mouse Colon-26 cells and activated Raw 264.7 cells in vitro and by inflamed mouse colitis tissues in vivo. The therapeutic efficacy of orally administrated NP-PEG-FA/17-AAG was evaluated in in vivo models using dextran sulphate sodium [DSS]-induced UC and azoxymethane [AOM]/DSS-induced CAC, and the results indicated that NP-PEG-FA/17-AAG significantly alleviated the symptoms of UC and CAC. More importantly, our inflamed colitis-targeted 17-AAG nano-formulation reduced systemic exposure and provided a degree of therapeutic response similar to that obtained by systemic administration [intraperitoneal] of 17-AAG, but at a ten-fold lower dose. Conclusions: We describe a convenient, orally administrated 17-AAG delivery system that exhibits enhanced efficacy in UC and CAC therapy while reducing systemic exposure. This system may represent a promising therapeutic approach for treating UC and CAC.