Background & Aims: The pathogenesis of inflammatory bowel disease (IBD) is believed to involve an altered balance between effector and regulatory T cells. Aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor that mediates the toxicity of dioxins, controls T-cell responses. We investigated the role of AhR in inflammation and pathogenesis of IBD in humans and mouse models.
Methods: AhR expression was evaluated in intestinal tissue samples from patients with IBD and controls by real-time polymerase chain reaction (PCR) and flow cytometry. Intestinal lamina propria mononuclear cells (LPMCs) were activated in the presence or absence of the AhR agonist 6-formylindolo(3, 2-b)carbazole (Ficz). Colitis was induced in mice using trinitrobenzene sulfonic acid (TNBS), dextran sulfate sodium (DSS), or T-cell transfer. Mice were given injections of Ficz or the AhR antagonist 2-metyl-2H-pyrazole-3-carboxylic acid; some mice first received injections of a blocking antibody against interleukin (IL)-22. Cytokines were quantified by real-time PCR and flow cytometry.
Results: Intestine tissue from patients with IBD expressed significantly less AhR than controls. In LPMCs from patients with IBD, incubation with Ficz reduced levels of interferon gamma (IFN)-γ and up-regulated IL-22. Mice injected with Ficz were protected against TNBS-, DSS-, and T-cell transfer-induced colitis; they had marked down-regulation of inflammatory cytokines and induction of IL-22. Mice given AhR antagonist produced more inflammatory cytokines and less IL-22 and developed a severe colitis. Neutralization of endogenous IL-22 disrupted the protective effect of Ficz on TNBS-induced colitis.
Conclusions: AhR is down-regulated in intestinal tissue of patients with IBD; AhR signaling, via IL-22, inhibits inflammation and colitis in the gastrointestinal tract of mice. AhR-related compounds might be developed to treat patients with IBDs.
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http://dx.doi.org/10.1053/j.gastro.2011.04.007 | DOI Listing |
Chirurgia (Bucur)
December 2024
we report the case of a recurrent giant pseudopolyp occurring in a patient without a history of inflammatory bowel disease (IBD), with an asymptomatic interval of nine years. Case Presentation: a 51-year-old Caucasian male with no relevant medical history was hospitalized for a subocclusive mass in the right colon, suspected to be neoplastic. He underwent a right hemicolectomy, and the histopathology revealed a giant pseudopolyp without malignancy.
View Article and Find Full Text PDFHealth Qual Life Outcomes
December 2024
Gastroenterology Unit, Pediatric Department, Santa Maria University Hospital - CHLN, Academic Medical Centre of Lisbon, Lisbon, Portugal.
Objectives: This study evaluated the clinical utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) by comparing it with objective clinical data and validated health-related quality of life (HRQOL) measures in pediatric Crohn's disease (CD) patients.
Study Design: Cross-sectional study. Pediatric CD patients (aged 8-17 years) were enrolled prospectively over eight months from an outpatient pediatric gastroenterology center.
BMC Gastroenterol
December 2024
Department of Inflammatory Bowel Disease, St Mark's National Bowel Hospital, Central Middlesex Hospital, Acton Lane, London, NW10 7NS, UK.
Background: With 20-40% of patients who have inflammatory bowel disease (IBD) not responding to therapy, resource use and costs can be high. We performed a descriptive analysis of health-care data for IBD management in the National Health Service to explore potential areas for improvement.
Methods: In this exploratory study, we analysed real-world data from the Discover dataset for adults with a diagnosis of incident IBD recorded in northwest London, UK, between 31 March, 2016, and 31 March, 2020.
BMC Gastroenterol
December 2024
Florence Nightingale Faculty of Nursing, Midwifery and Palliative Care, King's College London, 57 Waterloo Road, London, London, SE1 8WA, UK.
Background And Aims: The co-existence of fatigue, pain and faecal incontinence in people with Inflammatory Bowel Disease (IBD) is unknown. We aimed to determine the presence of and relationship between these symptoms and patients' desire for intervention.
Methods: Adults with IBD in the UK, recruited from clinics, the national IBD-BioResource, a patient charity and social media sources, completed PROMIS validated patient-reported questionnaires to identify fatigue, pain and faecal incontinence, in addition to symptom severity and impact, disease activity, anxiety and depression questionnaires and questions about their desire for help with these symptoms.
Cell Mol Gastroenterol Hepatol
December 2024
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, IL, USA; - Jesse Brown VA Medical Center, Chicago, IL, USA. Electronic address:
Diarrhea associated with enteric infections, gut inflammation, and genetic defects poses a major health burden and results in significant morbidity and mortality. Impaired fluid and electrolyte absorption and/or secretion in the intestine are the hallmark of diarrhea. Electroneutral NaCl absorption in the mammalian GI tract involves the coupling of Na/H and Cl/HCO exchangers.
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