RESUMO
OBJECTIVE: Irritable bowel syndrome (IBS) is a gut-brain disorder associated with increased gut permeability. Zonulin has been suggested to regulate the gut barrier and claimed to be pre-haptoglobin 2 (pre-HP2) and circulating zonulin is often used as a proxy for gastrointestinal permeability. This study investigated the correlation between colonic paracellular permeability and levels of circulating zonulin and pre-HP2. MATERIALS AND METHODS: Colonic biopsies from 32 patients with IBS and 15 healthy controls (HC) were used to measure permeability in Ussing chambers and levels of zonulin (Cusabio ELISA). Zonulin was also measured in blood samples from 40 HC, 78 patients with IBS and 20 patients with celiac disease (CeD), before and after a gluten-free diet. In addition, we verified HP genotype and circulating pre-HP2 using a monoclonal pre-HP2 antibody (Bio-Rad) by ELISA. RESULTS: Increased colonic paracellular permeability correlated positively with zonulin levels in IBS biopsies, but negatively with plasma zonulin. We found no agreement between circulating zonulin and pre-HP2. Genotyping revealed non-specificity of the zonulin kit, as all pre-HP2 non-producers presented detectable levels. Patients with CeD displayed higher pre-HP2 and zonulin levels compared to HC. A gluten-free diet in patients with CeD led to lower serum zonulin and pre-HP2 concentrations. CONCLUSIONS: Our study suggests that neither circulating zonulin nor pre-HP2 mirror colonic permeability. Our data corroborate previous reports showing the inability of the Cusabio zonulin kit to target zonulin and highlights that the results of studies using this kit must be re-examined with caution.
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Haptoglobinas , Mucosa Intestinal , Humanos , Permeabilidade , Precursores de ProteínasRESUMO
Immunofluorescence microscopy is an essential tool for tissue-based research, yet data reporting is almost always qualitative. Quantification of images, at the per-cell level, enables "flow cytometry-type" analyses with intact locational data but achieving this is complex. Gastrointestinal tissue, for example, is highly diverse: from mixed-cell epithelial layers through to discrete lymphoid patches. Moreover, different species (e.g., rat, mouse, and humans) and tissue preparations (paraffin/frozen) are all commonly studied. Here, using field-relevant examples, we develop open, user-friendly methodology that can encompass these variables to provide quantitative tissue microscopy for the field. Antibody-independent cell labeling approaches, compatible across preparation types and species, were optimized. Per-cell data were extracted from routine confocal micrographs, with semantic machine learning employed to tackle densely packed lymphoid tissues. Data analysis was achieved by flow cytometry-type analyses alongside visualization and statistical definition of cell locations, interactions and established microenvironments. First, quantification of Escherichia coli passage into human small bowel tissue, following Ussing chamber incubations exemplified objective quantification of rare events in the context of lumen-tissue crosstalk. Second, in rat jejenum, precise histological context revealed distinct populations of intraepithelial lymphocytes between and directly below enterocytes enabling quantification in context of total epithelial cell numbers. Finally, mouse mononuclear phagocyte-T cell interactions, cell expression and significant spatial cell congregations were mapped to shed light on cell-cell communication in lymphoid Peyer's patch. Accessible, quantitative tissue microscopy provides a new window-of-insight to diverse questions in gastroenterology. It can also help combat some of the data reproducibility crisis associated with antibody technologies and over-reliance on qualitative microscopy. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals LLC. on behalf of International Society for Advancement of Cytometry.
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Gastroenterologia , Nódulos Linfáticos Agregados , Animais , Citometria de Fluxo , Humanos , Camundongos , Microscopia , Ratos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: With a lifelong perspective, 12% of ulcerative colitis patients will need a colectomy. Further reconstruction via ileo-rectal anastomosis or pouch can be affected by patients' perspective of their quality of life after surgery. AIM: To assess the function and quality of life after restorative procedures with either ileo-rectal anastomosis or ileal pouch-anal anastomosis in relation to the inflammatory activity on endoscopy and in biopsies. METHOD: A total of 143 UC patients operated with subtotal colectomy and ileo-rectal anastomosis or pouches between 1992 and 2006 at Linköping University Hospital were invited to participate. Those who completed the validated questionnaires (Öresland score, SF-36, Short Health Scale) were offered an endoscopic evaluation including multiple biopsies. Associations between anorectal function and quality of life with type of restorative procedure and severity of endoscopic and histopathologic grading of inflammation were evaluated. RESULTS: Some 77 (53.9%) eligible patients completed questionnaires, of these 68 (88.3%) underwent endoscopic evaluation after a median follow-up of 12.5 (range 3.5-19.4) years after restorative procedure. Patients with ileo-rectal anastomosis reported better overall Öresland score: median = 3 (IQR 2-5) for ileo-rectal anastomosis (n = 38) and 10 (IQR 5-15) for pouch patients (n = 39) (p < 0.001). Anorectal function (Öresland score) and endoscopic findings (Baron-Ginsberg score) were positively correlated in pouch patients (tau: 0.28, p = 0.006). CONCLUSION: Patients operated with ileo-rectal anastomosis reported better continence compared to pouches. Minor differences were noted regarding the quality of life. Ileo-rectal anastomosis is a valid option for properly selected ulcerative colitis patients if strict postoperative endoscopic surveillance is carried out.
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Colite Ulcerativa/cirurgia , Bolsas Cólicas/efeitos adversos , Defecação , Incontinência Fecal/etiologia , Proctocolectomia Restauradora/efeitos adversos , Qualidade de Vida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/fisiopatologia , Colite Ulcerativa/psicologia , Incontinência Fecal/diagnóstico , Incontinência Fecal/fisiopatologia , Incontinência Fecal/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
The gut microbiome contributes to inflammatory bowel disease (IBD), in which bacteria can be present within the epithelium. Epithelial barrier function is decreased in IBD, and dysfunctional epithelial mitochondria and endoplasmic reticulum (ER) stress have been individually associated with IBD. We therefore hypothesized that the combination of ER and mitochondrial stresses significantly disrupt epithelial barrier function. Here, we treated human colonic biopsies, epithelial colonoids, and epithelial cells with an uncoupler of oxidative phosphorylation, dinitrophenol (DNP), with or without the ER stressor tunicamycin and assessed epithelial barrier function by monitoring internalization and translocation of commensal bacteria. We also examined barrier function and colitis in mice exposed to dextran sodium sulfate (DSS) or DNP and co-treated with DAPK6, an inhibitor of death-associated protein kinase 1 (DAPK1). Contrary to our hypothesis, induction of ER stress (i.e. the unfolded protein response) protected against decreased barrier function caused by the disruption of mitochondrial function. ER stress did not prevent DNP-driven uptake of bacteria; rather, specific mobilization of the ATF6 arm of ER stress and recruitment of DAPK1 resulted in enhanced autophagic killing (xenophagy) of bacteria. Of note, epithelia with a Crohn's disease-susceptibility mutation in the autophagy gene ATG16L1 exhibited less xenophagy. Systemic delivery of the DAPK1 inhibitor DAPK6 increased bacterial translocation in DSS- or DNP-treated mice. We conclude that promoting ER stress-ATF6-DAPK1 signaling in transporting enterocytes counters the transcellular passage of bacteria evoked by dysfunctional mitochondria, thereby reducing the potential for metabolic stress to reactivate or perpetuate inflammation.
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Proteínas Quinases Associadas com Morte Celular/metabolismo , Estresse do Retículo Endoplasmático , Mitocôndrias/metabolismo , Fator 6 Ativador da Transcrição/metabolismo , Idoso , Animais , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Feminino , Humanos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Permeabilidade , Tunicamicina/farmacologiaRESUMO
OBJECTIVE: Infliximab is important in the therapeutic arsenal of Crohn's disease (CD). However, its effect on mucosal barrier function is not fully understood. Adherent-invasive Escherichia coli (AIEC) are important in CD pathophysiology, but the transmucosal uptake routes are partly unknown. We investigated effects of infliximab on uptake of colon-specific AIEC HM427 across CD colonic mucosa. MATERIALS AND METHODS: Endoscopic biopsies from non-inflamed colon of seven patients with CD, before and after two infliximab infusions, and eight non-inflammation controls, were mounted in Ussing chambers. Paracellular permeability (51Cr-EDTA) and transmucosal passage of GFP-expressing HM427 were studied. Mechanisms of HM427 transepithelial transport were investigated in Caco-2 monolayers treated with TNF, in the presence of infliximab and/or endocytosis inhibitors. RESULTS: Before infliximab treatment, colonic passage of HM427 [CD: 2475 CFU (450-3000); controls 1163(225-1950)] and 51Cr-EDTA permeability were increased in CD (p < .05), but were restored to control levels by infliximab (CD: 150 (18.8-1069)). In TNF-exposed Caco-2 monolayers HM427 transport and lipid rafts/HM427 co-localization was decreased by infliximab. The lipid raft inhibitor methyl-ß-cyclodextrin decreased HM427 transport. CONCLUSION: Infliximab restored the colonic barrier to AIEC in CD; an effect partially mediated by blocking lipid rafts in epithelial cells. This ability likely contributes to infliximab's clinical efficacy in colonic CD.
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Doença de Crohn/tratamento farmacológico , Doença de Crohn/microbiologia , Infecções por Escherichia coli/prevenção & controle , Infliximab/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Microdomínios da Membrana/efeitos dos fármacos , Adulto , Células CACO-2 , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Feminino , Humanos , Mucosa Intestinal/microbiologia , Masculino , Adulto JovemRESUMO
BACKGROUND AND AIMS: Altered intestinal barrier is associated with immune activation and clinical symptoms in diarrhoea-predominant IBS (IBS-D). Increased mucosal antigen load may induce specific responses; however, local antibody production and its contribution to IBS aetiopathogenesis remain undefined. This study evaluated the role of humoral activity in IBS-D. METHODS: A single mucosal jejunal biopsy, luminal content and blood were obtained from healthy volunteers (H; n=30) and IBS-D (n=49; Rome III criteria) participants. Intraepithelial lymphocytes, mast cells, B lymphocytes and plasma cells were studied by imaging techniques. Differential gene expression and pathway analysis were assessed by microarray and PCR techniques. Blood and luminal immunoglobulins (Igs) were quantified. Gastrointestinal symptoms, respiratory atopy and stress and depression were also recorded. RESULTS: Patients with IBS-D showed a higher number and activation of mucosal B lymphocytes and plasma cells (p<0.05). Mast cell density was increased in patients with IBS-D (non-atopic) and in close proximity to plasma cells (p<0.05). Microarray profiling identified differential humoral activity in IBS-D, involving proliferation and activation of B lymphocytes and Igs production (p<0.001). Mucosal humoral activity was higher in IBS-D, with upregulation of germline transcripts and Ig genes (1.3-fold-1.7-fold increase; p<0.05), and increased IgG(+) cells and luminal IgG compared with H (p<0.05), with no differences in blood. Biological markers of humoral activity correlated positively with bowel movements, stool form and depression. CONCLUSIONS: Enhanced small bowel humoral immunity is a distinctive feature of IBS-D. Mucosal Ig production contributes to local inflammation and clinical manifestations in IBS-D.
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Imunidade Humoral/imunologia , Mucosa Intestinal/imunologia , Síndrome do Intestino Irritável/imunologia , Síndrome do Intestino Irritável/fisiopatologia , Jejuno/patologia , Adulto , Análise de Variância , Biópsia por Agulha , Estudos de Casos e Controles , Diarreia/imunologia , Diarreia/patologia , Progressão da Doença , Feminino , Imunofluorescência , Humanos , Imunoglobulinas/imunologia , Imunoglobulinas/metabolismo , Imuno-Histoquímica , Mucosa Intestinal/patologia , Jejuno/imunologia , Masculino , Microscopia Eletrônica de Transmissão/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto JovemRESUMO
Epithelial permeability is often increased in inflammatory bowel diseases. We hypothesized that perturbed mitochondrial function would cause barrier dysfunction and hence epithelial mitochondria could be targeted to treat intestinal inflammation. Mitochondrial dysfunction was induced in human colon-derived epithelial cell lines or colonic biopsy specimens using dinitrophenol, and barrier function was assessed by transepithelial flux of Escherichia coli with or without mitochondria-targeted antioxidant (MTA) cotreatment. The impact of mitochondria-targeted antioxidants on gut permeability and dextran sodium sulfate (DSS)-induced colitis in mice was tested. Mitochondrial superoxide evoked by dinitrophenol elicited significant internalization and translocation of E. coli across epithelia and control colonic biopsy specimens, which was more striking in Crohn's disease biopsy specimens; the mitochondria-targeted antioxidant, MitoTEMPO, inhibited these barrier defects. Increased gut permeability and reduced epithelial mitochondrial voltage-dependent anion channel expression were observed 3 days after DSS. These changes and the severity of DSS-colitis were reduced by MitoTEMPO treatment. In vitro DSS-stimulated IL-8 production by epithelia was reduced by MitoTEMPO. Metabolic stress evokes significant penetration of commensal bacteria across the epithelium, which is mediated by mitochondria-derived superoxide acting as a signaling, not a cytotoxic, molecule. MitoTEMPO inhibited this barrier dysfunction and suppressed colitis in DSS-colitis, likely via enhancing barrier function and inhibiting proinflammatory cytokine production. These novel findings support consideration of MTAs in the maintenance of epithelial barrier function and the management of inflammatory bowel diseases.
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Colite/patologia , Mucosa Intestinal/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Colite/fisiopatologia , Modelos Animais de Doenças , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Permeabilidade , Reação em Cadeia da Polimerase Via Transcriptase ReversaAssuntos
Colite Ulcerativa/cirurgia , Infecções por Coronavirus/epidemiologia , Doença de Crohn/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Obstrução Intestinal/cirurgia , Perfuração Intestinal/cirurgia , Pneumonia Viral/epidemiologia , Abscesso/cirurgia , Infecções Assintomáticas , Betacoronavirus , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Cirurgia Colorretal , Infecções por Coronavirus/diagnóstico , Gerenciamento Clínico , Emergências , Reações Falso-Negativas , Humanos , Controle de Infecções , Salas Cirúrgicas , Pandemias , Equipe de Assistência ao Paciente , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase , Guias de Prática Clínica como Assunto , Cuidados Pré-Operatórios , SARS-CoV-2 , Sensibilidade e Especificidade , Fatores de Tempo , VentilaçãoRESUMO
BACKGROUND: The aim of this study was to examine the effect of colitis and anti-inflammatory therapies on the healing of colonic anastomoses in mice. METHODS: Female C57BL/6 mice were randomized into eight groups; four groups receiving plain tap-water and four groups receiving dextran sulfate sodium. Intra-peritoneal treatment was given therapeutically for 14 days with placebo, prednisolone, azathioprine, or infliximab (IFX). Colonic anastomoses were performed and bursting pressure (BP) measurements were recorded and the inflammation evaluated with histology and zymography. RESULTS: The mice with colitis had a more active inflammation based on histology and bowel weight compared with the tap water group, 8.3 (7.6-9.5) mg/mm and 5.5 (4.8-6.2) mg/mm respectively (p < 0.0001). Similarly mice with colitis receiving placebo had a more active inflammation, 12.8 (10.6-15.0) mg/mm, which differed significantly from all the other therapy arms among the colitic mice; prednisolone 8.1 (7.5-9.1) mg/mm (p = 0.014), azathioprine 8.2 (7.0-8.5) mg/mm (p = 0.0046), IFX 6.7 (6.4-7.9) mg/mm (p = 0.0055). BP for the placebo group was 90.0 (71.5-102.8) mmHg and did not differ from azathioprine or IFX groups, 84.4 (70.5-112.5) and 92.3 (75.8-122.3) mmHg respectively. In contrast BP for the prednisolone group was significantly decreased compared to placebo, 55.5 (42.8-73.0) mmHg (p = 0.0004). CONCLUSIONS: All therapies had a beneficial effect on the colitis. An impaired BP of colonic anastomoses was noted after preoperative steroids but not after azathioprine or IFX in this model.
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Anti-Inflamatórios/uso terapêutico , Azatioprina/uso terapêutico , Colite/tratamento farmacológico , Colite/patologia , Infliximab/uso terapêutico , Prednisolona/uso terapêutico , Anastomose Cirúrgica/efeitos adversos , Animais , Colite/induzido quimicamente , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Pressão , Cicatrização/efeitos dos fármacosRESUMO
OBJECTIVE: Functional dyspepsia (FD) is an extremely common functional gastrointestinal disorder, the pathophysiology of which is poorly understood. We hypothesised that impaired intestinal barrier function is involved in the onset and persistence of this disorder by inducing low-grade inflammation. Therefore, our aim was to evaluate duodenal mucosal integrity and low-grade inflammation in patients with FD. DESIGN: Duodenal biopsy specimens were obtained from 15 patients with FD fulfilling the Rome III criteria and 15 age- and gender-matched healthy volunteers. Transepithelial electrical resistance (TEER) and paracellular permeability were measured in Ussing chambers. Expression of cell-to-cell adhesion proteins was evaluated by real-time PCR, western blot and/or immunofluorescence. Numbers of mast cells, eosinophils and intraepithelial lymphocytes were assessed by immunohistochemistry. RESULTS: Patients with FD displayed lower TEER and increased paracellular passage compared with healthy controls, which is indicative of impaired mucosal integrity. In addition, abnormal expression of cell-to-cell adhesion proteins at the level of tight junctions, adherens junctions and desmosomes was shown. Furthermore, patients were characterised by the presence of low-grade inflammation, as demonstrated by increased infiltration of mucosal mast cells and eosinophils. A significant association between the expression level of several cell-to-cell adhesion proteins, the extent of increased permeability and the severity of low-grade inflammation was found. CONCLUSIONS: These findings challenge the classical paradigm that patients with FD show no structural changes in the gastrointestinal tract. We suggest that impaired intestinal barrier function is a pathophysiological mechanism in FD. Thus, restoration of intestinal barrier integrity may be a potential therapeutic target for treating patients with FD.
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Duodeno/patologia , Dispepsia/patologia , Inflamação/patologia , Mucosa Intestinal/patologia , Junções Íntimas/metabolismo , Adolescente , Adulto , Bélgica , Western Blotting , Duodeno/metabolismo , Duodeno/fisiopatologia , Dispepsia/metabolismo , Dispepsia/fisiopatologia , Impedância Elétrica , Feminino , Imunofluorescência , Voluntários Saudáveis , Humanos , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/fisiopatologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Permeabilidade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Adulto JovemRESUMO
INTRODUCTION: The absence of reliable prognostic markers poses a challenge to the management of inflammatory bowel disease (IBD). Patients with aggressive disease may not receive sufficient treatment with conventional 'step-up' therapy, whereas a top-down approach may expose patients with indolent disease to unnecessary treatment-related toxicity. The objective of the Nordic IBD treatment strategy trial (NORDTREAT) is to assess the feasibility of personalised therapy by stratifying patients according to a prognostic serum protein signature at diagnosis. METHODS AND ANALYSIS: NORDTREAT is a multicentre, biomarker-strategy design, open-label controlled trial. After screening consent, eligible patients are randomised (1:1) into one of two groups: a group with access to the protein signature and a group without access. In the access to protein signature group, patients displaying a protein signature suggestive of an increased risk of an aggressive disease course will be treated in line with a top-down treatment algorithm (anti-tumour necrosis factor agent with/without an immunomodulator). In contrast, those with a protein signature indicative of indolent disease will be excluded from the trial. Patients not in the access group receive treatment based on clinical management. This traditional management involves a stepwise escalation of treatment as determined by the investigator after failure of first-line treatment. After 52 weeks, outcomes are assessed in the subgroup of patients with a protein profile indicating a potentially severe disease trajectory. The primary endpoint is a composite of the proportion of patients with corticosteroid-free clinical and endoscopic remission at week 52. Surgical intervention due to IBD during follow-up will be defined as treatment failure. ETHICS AND DISSEMINATION: Ethical approval has been obtained, and recruitment is underway at sites in four participating Nordic countries (Denmark, Iceland, Norway and Sweden). Following trial completion and data analysis, the trial results will be submitted for publication in peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBER: NCT05180175; Pre-results. EudraCT number: 2019-002942-19.
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Biomarcadores , Doenças Inflamatórias Intestinais , Humanos , Biomarcadores/sangue , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Prognóstico , Medicina de Precisão/métodos , Países Escandinavos e Nórdicos , Fatores Imunológicos/uso terapêuticoRESUMO
INTRODUCTION: Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, can be challenging to diagnose, and treatment outcomes are difficult to predict. In the NORDTREAT cohort study, a Nordic prospective multicentre study, we aim to identify novel molecular biomarkers of diagnostic value by assessing the diagnostic test accuracy (cross-sectionally), as well as the prognostic utility when used as prognostic markers in the long-term (cohort study). In the diagnostic test accuracy study, the primary outcome is a successful diagnosis using one or more novel index tests at baseline compared with the ECCO criteria as the reference standard. The composite outcome of the prognostic utility study is 'severe IBD' within 52 weeks from inclusion, defined as one or more of the following three events: IBD-related surgery, IBD-related hospitalisation or IBD-related death. METHODS AND ANALYSIS: We aim to recruit 800 patients referred on suspicion of IBD to this longitudinal observational study, a collaboration between 11 inclusion sites in Denmark, Iceland, Norway and Sweden. Inclusion will occur from February 2022 until December 2023 with screening and baseline visits for all participants and three outcome visits at weeks 12, 26 and 52 after baseline for IBD-diagnosed patients. Biological material (blood, faeces, biopsies, urine and hair), clinical data and lifestyle information will be collected during these scheduled visits. ETHICS AND DISSEMINATION: This study will explore novel biomarkers to improve diagnostic accuracy and prediction of disease progression, thereby improving medical therapy and the quality of life for patients with IBD.The study is approved by the Ethics Committee (DK: S-20200051, v1.4, 16.10.2021; IS: VSNb2021070006/03.01, NO: 193064; SE: DNR 2021-05090) and the Danish Data Protecting Agency (20/54594). Results will be disseminated through peer-reviewed journals, patient associations and presentations at international conferences. CLINICAL TRIAL REGISTRATION NUMBER: NCT05414578; Pre-results.
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Biomarcadores , Doenças Inflamatórias Intestinais , Humanos , Doença de Crohn/diagnóstico , Doença de Crohn/terapia , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/terapia , Estudos Longitudinais , Estudos Multicêntricos como Assunto , Prognóstico , Estudos Prospectivos , Projetos de Pesquisa , Países Escandinavos e NórdicosRESUMO
BACKGROUND: Faecal biomarkers can be used to assess inflammatory bowel disease (IBD). AIM: To explore the performance of some promising biomarkers in diagnosing and predicting disease course in IBD. METHODS: We included 65 patients with treatment-naïve, new-onset Crohn's disease (CD), 90 with ulcerative colitis (UC), 67 symptomatic controls (SC) and 41 healthy controls (HC) in this prospective observational study. We analysed faecal samples for calprotectin (FC), myeloperoxidase (MPO), human neutrophil lipocalin (HNL), eosinophil cationic protein ECP and eosinophil-derived neurotoxin (EDN) and compared markers among groups. We assessed the diagnostic capability of biomarkers with receiver operating characteristic curves. Clinical disease course was determined for each patient with IBD and analysed the association with biomarkers by logistic regression. RESULTS: All markers were elevated at inclusion in patients with IBD compared with HC (p < 0.001) and SC (p < 0.001). FC (AUC 0.85, 95% CI: 0.79-0.89) and MPO (AUC 0.85, 95% CI: 0.80-0.89) showed the highest diagnostic accuracy in distinguishing IBD from SC. The diagnostic ability of biomarkers differed between IBD subtypes with the highest performance for FC and MPO in CD. The diagnostic accuracy was further improved by combining FC and MPO (p = 0.02). Levels of FC, MPO and HNL at inclusion were predictive of an aggressive disease course with MPO showing the strongest association (p = 0.006). CONCLUSIONS: This study provides new insight into the diagnostic and prognostic capability of neutrophil and eosinophil biomarkers in IBD and suggests that MPO, alone or in combination with FC, may add to the diagnostic power of faecal biomarkers.
RESUMO
Improved biomarkers are needed for pediatric inflammatory bowel disease. Here we identify a diagnostic lipidomic signature for pediatric inflammatory bowel disease by analyzing blood samples from a discovery cohort of incident treatment-naïve pediatric patients and validating findings in an independent inception cohort. The lipidomic signature comprising of only lactosyl ceramide (d18:1/16:0) and phosphatidylcholine (18:0p/22:6) improves the diagnostic prediction compared with high-sensitivity C-reactive protein. Adding high-sensitivity C-reactive protein to the signature does not improve its performance. In patients providing a stool sample, the diagnostic performance of the lipidomic signature and fecal calprotectin, a marker of gastrointestinal inflammation, does not substantially differ. Upon investigation in a third pediatric cohort, the findings of increased lactosyl ceramide (d18:1/16:0) and decreased phosphatidylcholine (18:0p/22:6) absolute concentrations are confirmed. Translation of the lipidomic signature into a scalable diagnostic blood test for pediatric inflammatory bowel disease has the potential to support clinical decision making.
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Biomarcadores , Doenças Inflamatórias Intestinais , Lipidômica , Humanos , Criança , Lipidômica/métodos , Masculino , Feminino , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/metabolismo , Biomarcadores/sangue , Adolescente , Fezes/química , Fosfatidilcolinas/sangue , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Pré-Escolar , Complexo Antígeno L1 Leucocitário/sangue , Complexo Antígeno L1 Leucocitário/análise , Estudos de CoortesRESUMO
OBJECTIVE. The intestinal microbiota plays a substantial role in the pathogenesis of inflammatory bowel disease (IBD). Faecalibacterium prausnitzii (FP) is underrepresented in IBD patients and have been suggested to have anti-inflammatory effects in mice. Increased intestinal permeability is common in IBD but the relationship between FP and intestinal barrier function has not been investigated. Our aim was to study treatment with FP supernatant on intestinal barrier function in a dextran sodium sulfate (DSS) colitis mice model. MATERIAL AND METHODS. C57BL/6 mice received 3% DSS in tap water ad libitum during five days to induce colitis. From day 3 the mice received a daily gavage with FP supernatant or broth during seven days. Ileum and colon were mounted in Ussing chambers for permeability studies with (51)Cr-EDTA and Escherichia coli K-12. Colon was saved for Western blot analyses of tight junction proteins. RESULTS. DSS-treated mice showed significant weight loss and colon shortening. Gavage with FP supernatant resulted in a quicker recovery after DSS treatment and less extensive colonic shortening. Ileal mucosa of DSS mice showed a significant increase in (51)Cr-EDTA-passage compared to controls. (51)Cr-EDTA passage was significantly decreased in mice receiving FP supernatant. No significant differences were observed in passage of E. coli K12. Western blots showed a trend to increased claudin-1 and claudin-2 expressions in DSS mice. CONCLUSIONS. Supernatant of FP enhances the intestinal barrier function by affecting paracellular permeability, and may thereby attenuate the severity of DSS-induced colitis in mice. These findings suggest a potential role of FP in the treatment of IBD.
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Colite/terapia , Colo/metabolismo , Bactérias Gram-Positivas , Íleo/metabolismo , Mucosa Intestinal/metabolismo , Probióticos/farmacologia , Junções Íntimas/metabolismo , Administração Oral , Animais , Biomarcadores/metabolismo , Western Blotting , Claudina-1/metabolismo , Claudina-2/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Sulfato de Dextrana , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade , Probióticos/administração & dosagem , Distribuição AleatóriaRESUMO
BACKGROUND: Psychological stress and increased permeability are implicated as contributing factors in the initiation and worsening of gastrointestinal diseases. A link between stress and intestinal permeability has been shown in animal models as well as in human small intestine, but stress effects on the human colorectal mucosal barrier has not been reported. OBJECTIVE: To investigate the potential effects of acute psychological stress on colorectal mucosal barrier function and to explore stress-induced molecular events in the rectal mucosa under healthy conditions. METHODS: Endoscopic biopsies were taken from the rectosigmoid region of healthy volunteers, who had been subjected to dichotomous listening stress and after a control session, respectively. Paracellular and transcellular permeability were assessed in modified Ussing chambers. RNA expression (microarray technology confirmed by quantitative real-time polymerase chain reaction) and biological pathway analysis were used to investigate the local mucosal response to acute stress. RESULTS: Dichotomous listening stress induced a subjective and objective stress response, and significantly increased paracellular but not transcellular permeability. We also identified a stress-induced reduction in RNA expression of genes related to immune cell activation and maturation (CR2, CD20, TCLA1, BANK1, CD22, FDCSP), signaling molecules of homing of immune cells to the gut (chemokines: CCL21, CXCL13, and CCL19, and receptors: CCR7, CXCR5), and innate immunity (DUOX2). Eight of the 10 top down-regulated genes are directly involved in B cell activation, signaling and migration. The systemic stress response correlated positively with paracellular permeability and negatively with DUOX2 expression. CONCLUSION: Dichotomous listening stress increases paracellular permeability and modulates immune cell activity in the rectal mucosa. Further studies are warranted to identify the primary mechanisms of stress-mediated reduction of mucosal defensive activity and barrier dysfunction, and their potential implications for gastrointestinal disorders.
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Neoplasias Colorretais , Gastroenteropatias , Animais , Humanos , Oxidases Duais/metabolismo , Oxidases Duais/farmacologia , Voluntários Saudáveis , Mucosa Intestinal/patologia , Permeabilidade , Neoplasias Colorretais/patologia , RNA/metabolismo , RNA/farmacologiaRESUMO
Gut bacteria provide benefits to the host and have been implicated in inflammatory bowel disease (IBD), where adherent-invasive E. coli (AIEC) pathobionts (e.g., strain LF82) are associated with Crohn's disease. E. coli-LF82 causes fragmentation of the epithelial mitochondrial network, leading to increased epithelial permeability. We hypothesized that butyrate would limit the epithelial mitochondrial disruption caused by E. coli-LF82. Human colonic organoids and the T84 epithelial cell line infected with E. coli-LF82 (MOI = 100, 4 h) showed a significant increase in mitochondrial network fission that was reduced by butyrate (10 mM) co-treatment. Butyrate reduced the loss of mitochondrial membrane potential caused by E. coli-LF82 and increased expression of PGC-1α mRNA, the master regulator of mitochondrial biogenesis. Metabolomics revealed that butyrate significantly altered E. coli-LF82 central carbon metabolism leading to diminished glucose uptake and increased succinate secretion. Correlating with preservation of mitochondrial network form/function, butyrate reduced E. coli-LF82 transcytosis across T84-cell monolayers. The use of the G-protein inhibitor, pertussis toxin, implicated GPCR signaling as critical to the effect of butyrate, and the free fatty acid receptor three (FFAR3, GPR41) agonist, AR420626, reproduced butyrate's effect in terms of ameliorating the loss of barrier function and reducing the mitochondrial fragmentation observed in E. coli-LF82 infected T84-cells and organoids. These data indicate that butyrate helps maintain epithelial mitochondrial form/function when challenged by E. coli-LF82 and that this occurs, at least in part, via FFAR3. Thus, loss of butyrate-producing bacteria in IBD in the context of pathobionts would contribute to loss of epithelial mitochondrial and barrier functions that could evoke disease and/or exaggerate a low-grade inflammation.
Assuntos
Doença de Crohn , Infecções por Escherichia coli , Microbioma Gastrointestinal , Humanos , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Mucosa Intestinal/microbiologia , Ácidos Graxos não Esterificados/metabolismo , Butiratos/farmacologia , Butiratos/metabolismo , Doença de Crohn/microbiologia , Aderência Bacteriana/genéticaRESUMO
INTRODUCTION: Fecal calprotectin (FC) is a noninvasive tool for examining response to biologics in inflammatory bowel disease (IBD), but its performance in relation to other novel fecal markers of various cellular origins is unknown. METHODS: We performed a prospective multicenter cohort study and included patients with active IBD who provided a fecal sample at initiation of biological therapy. Levels of FC, myeloperoxidase (MPO), human neutrophil lipocalin (HNL), and eosinophil-derived neurotoxin (EDN) were analyzed and related to clinical remission status at 3 months. Changes in levels of markers at 3 months were calculated, and the impact of concomitant use of corticosteroids at baseline was estimated. RESULTS: In patients achieving clinical remission (n = 27), a decrease in levels of FC ( P = 0.005), MPO ( P < 0.001), HNL ( P < 0.001), and EDN ( P < 0.001) was observed, whereas no significant decrease was seen in patients not achieving remission (n = 39). There was a significant difference in the change in the level of MPO ( P = 0.01) and HNL ( P = 0.02) between patients achieving clinical remission and those who did not, but changes in FC and EDN could not differentiate between these groups. Patients with concomitant systemic corticosteroids at inclusion had lower levels of HNL ( P = 0.01) and EDN ( P < 0.001) at baseline, compared with patients without corticosteroids. DISCUSSION: Fecal MPO, HNL, and EDN are all promising biomarkers for assessing the treatment outcome of biologics in patients with IBD. Fecal levels of EDN and HNL are significantly affected by corticosteroids indicating a greater sensitivity to the effects of corticosteroids compared with levels of FC and MPO.
Assuntos
Doenças Inflamatórias Intestinais , Neutrófilos , Humanos , Eosinófilos , Estudos Prospectivos , Estudos de Coortes , Doenças Inflamatórias Intestinais/tratamento farmacológico , Lipocalinas , Biomarcadores , Neurotoxina Derivada de Eosinófilo , Corticosteroides/uso terapêutico , Terapia BiológicaRESUMO
BACKGROUND & AIMS: Altered intestinal barrier function has been implicated in the pathophysiology of ulcerative colitis (UC) in genetic, functional, and epidemiological studies. Mast cells and corticotropin-releasing factor (CRF) regulate the mucosal barrier in human colon. Because eosinophils are often increased in colon tissues of patients with UC, we assessed interactions among mast cells, CRF, and eosinophils in the mucosal barrier of these patients. METHODS: Transmucosal fluxes of protein antigens (horseradish peroxidase) and paracellular markers ((51)Cr-EDTA, fluorescein isothiocyanate-dextran 4000) were studied in noninflamed, colonic mucosal biopsy samples collected from 26 patients with UC and 53 healthy volunteers (controls); samples were mounted in Ussing chambers. We also performed fluorescence and electron microscopy of human tissue samples, assessed isolated eosinophils, and performed mechanistic studies using in vitro cocultured eosinophils (15HL-60), mast cells (HMC-1), and a colonic epithelial cell line (T84). RESULTS: Colon tissues from patients with UC had significant increases in permeability to protein antigens compared with controls. Permeability was blocked by atropine (a muscarinic receptor antagonist), α-helical CRF(9-41) (a CRF receptor antagonist), and lodoxamide (a mast-cell stabilizer). Eosinophils were increased in number in UC tissues (compared with controls), expressed the most M2 and M3 muscarinic receptors of any mucosal cell type, and had immunoreactivity to CRF. In coculture studies, carbachol activation of eosinophils caused production of CRF and activation of mast cells, which increased permeability of T84 epithelial cells to macromolecules. CONCLUSIONS: We identified a neuroimmune intercellular circuit (from cholinergic nerves, via eosinophils to mast cells) that mediates colonic mucosal barrier dysfunction in patients with UC. This circuit might exacerbate mucosal inflammation.
Assuntos
Colite Ulcerativa/metabolismo , Hormônio Liberador da Corticotropina/biossíntese , Eosinófilos/metabolismo , Mucosa Intestinal/metabolismo , Receptores Muscarínicos/biossíntese , Atropina/farmacologia , Biópsia , Linhagem Celular , Colite Ulcerativa/patologia , Hormônio Liberador da Corticotropina/efeitos dos fármacos , Eosinófilos/efeitos dos fármacos , Eosinófilos/ultraestrutura , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/ultraestrutura , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Mastócitos/ultraestrutura , Microscopia Eletrônica de Transmissão e Varredura , Antagonistas Muscarínicos/farmacologia , Receptores Muscarínicos/efeitos dos fármacosRESUMO
Enteric glial cells (EGC) are known to regulate gastrointestinal functions; however, their role in Crohn's disease (CD) is elusive. Microscopic erosions over the ileal Peyer's patches are early signs of CD. The aim of this work was to assess the localization of EGC in the follicle and interfollicular region of the Peyer's patches and in the lamina propria and study the effects of EGC mediators on barrier function in CD patients and non-inflammatory bowel disease (non-IBD) controls. EGC markers, glial fibrillary acidic protein (GFAP), and S100 calcium-binding protein ß (S100ß) were quantified by immunofluorescence and Western blotting. Both markers showed significantly more EGC in the Peyer's patches and lamina propria of CD patients compared to the non-IBD controls. In CD patients there were significantly more EGC in Peyer's patches compared to lamina propria, while the opposite pattern was seen in controls. Barrier function studies using Ussing chambers showed increased paracellular permeability by EGC mediators in CD patients, whereas permeability decreased by the mediators in controls. We show the accumulation of EGC in Peyer's patches of CD patients. Moreover, EGC mediators induced barrier dysfunction in CD patients. Thus, EGC might have harmful impacts on ongoing inflammation and contribute to the pathophysiology of the disease.