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Hussein H, Van Remoortel S, Boeckxstaens GE. Irritable bowel syndrome: When food is a pain in the gut. Immunol Rev 2024. [PMID: 39037230 DOI: 10.1111/imr.13374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
Irritable bowel syndrome (IBS) is a chronic gastrointestinal condition associated with altered bowel habits and recurrent abdominal pain, often triggered by food intake. Current treatments focus on improving stool pattern, but effective treatments for pain in IBS are still lacking due to our limited understanding of pathophysiological mechanisms. Visceral hypersensitivity (VHS), or abnormal visceral pain perception, underlies abdominal pain development in IBS, and mast cell activation has been shown to play an important role in the development of VHS. Our work recently revealed that abdominal pain in response to food intake is induced by the sensitization of colonic pain-sensing neurons by histamine produced by activated mast cells following a local IgE response to food. In this review, we summarize the current knowledge on abdominal pain and VHS pathophysiology in IBS, we outline the work leading to the discovery of the role of histamine in abdominal pain, and we introduce antihistamines as a novel treatment option to manage chronic abdominal pain in patients with IBS.
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Affiliation(s)
- Hind Hussein
- Center for Intestinal Neuro-Immune Interactions, Translational Research in Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism, and Ageing (CHROMETA), KU Leuven, Leuven, Belgium
| | - Samuel Van Remoortel
- Center for Intestinal Neuro-Immune Interactions, Translational Research in Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism, and Ageing (CHROMETA), KU Leuven, Leuven, Belgium
| | - Guy E Boeckxstaens
- Center for Intestinal Neuro-Immune Interactions, Translational Research in Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism, and Ageing (CHROMETA), KU Leuven, Leuven, Belgium
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2
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Chen Y, Feng S, Li Y, Zhang C, Chao G, Zhang S. Gut microbiota and intestinal immunity-A crosstalk in irritable bowel syndrome. Immunology 2024; 172:1-20. [PMID: 38174581 DOI: 10.1111/imm.13749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024] Open
Abstract
Irritable bowel syndrome (IBS), one of the most prevalent functional gastrointestinal disorders, is characterized by recurrent abdominal pain and abnormal defecation habits, resulting in a severe healthcare burden worldwide. The pathophysiological mechanisms of IBS are multi-factorially involved, including food antigens, visceral hypersensitivity reactions, and the brain-gut axis. Numerous studies have found that gut microbiota and intestinal mucosal immunity play an important role in the development of IBS in crosstalk with multiple mechanisms. Therefore, based on existing evidence, this paper elaborates that the damage and activation of intestinal mucosal immunity and the disturbance of gut microbiota are closely related to the progression of IBS. Combined with the application prospect, it also provides references for further in-depth exploration and clinical practice.
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Affiliation(s)
- Yuxuan Chen
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Shuyan Feng
- The First Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Ying Li
- The First Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Chi Zhang
- Sir Run Run Shaw Hospital of Zhejiang University, Hangzhou, China
| | - Guanqun Chao
- Department of General Practice, Sir Run Run Shaw Hospital of Zhejiang University, Hangzhou, China
| | - Shuo Zhang
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
- Department of Gastroenterology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
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3
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Vanuytsel T, Bercik P, Boeckxstaens G. Understanding neuroimmune interactions in disorders of gut-brain interaction: from functional to immune-mediated disorders. Gut 2023; 72:787-798. [PMID: 36657961 PMCID: PMC10086308 DOI: 10.1136/gutjnl-2020-320633] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 12/08/2022] [Indexed: 01/21/2023]
Abstract
Functional gastrointestinal disorders-recently renamed into disorders of gut-brain interaction-such as irritable bowel syndrome and functional dyspepsia are highly prevalent conditions with bothersome abdominal symptoms in the absence of structural abnormalities. While traditionally considered as motility disorders or even psychosomatic conditions, our understanding of the pathophysiology has evolved significantly over the last two decades. Initial observations of subtle mucosal infiltration with immune cells, especially mast cells and eosinophils, are since recently being backed up by mechanistic evidence demonstrating increased release of nociceptive mediators by immune cells and the intestinal epithelium. These mediators can activate sensitised neurons leading to visceral hypersensitivity with bothersome symptoms. The interaction between immune activation and an impaired barrier function of the gut is most likely a bidirectional one with alterations in the microbiota, psychological stress and food components as upstream players in the pathophysiology. Only few immune-targeting treatments are currently available, but an improved understanding through a multidisciplinary scientific approach will hopefully identify novel, more precise treatment targets with ultimately better outcomes.
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Affiliation(s)
- Tim Vanuytsel
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases and Metabolism (ChroMeta), KU Leuven, Leuven, Belgium.,Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium
| | - Premysl Bercik
- Faculty of Health Sciences, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Guy Boeckxstaens
- Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases and Metabolism (ChroMeta), KU Leuven, Leuven, Belgium .,Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium
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4
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Santoso AD, De Ridder D. Fatty Acid Amide Hydrolase: An Integrative Clinical Perspective. Cannabis Cannabinoid Res 2023; 8:56-76. [PMID: 35900294 DOI: 10.1089/can.2021.0237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: Fatty acid amide hydrolase (FAAH) is one of the main terminating enzymes of the endocannabinoid system (ECS). Since being discovered in 1996, the modulation of FAAH has been viewed as a compelling alternative strategy to obtain the beneficial effect of the ECS. With a considerable amount of FAAH-related publication over time, the next step would be to comprehend the proximity of this evidence for clinical application. Objective: This review intends to highlight the rationale of FAAH modulation and provide the latest evidence from clinical studies. Methods: Publication searches were conducted to gather information focused on FAAH-related clinical evidence with an extension to the experimental research to understand the biological plausibility. The subtopics were selected to be multidisciplinary to offer more perspective on the current state of the arts. Discussion: Experimental and clinical studies have demonstrated that FAAH was highly expressed not only in the central nervous system but also in the peripheral tissues. As the key regulator of endocannabinoid signaling, it would appear that FAAH plays a role in the modulation of mood and emotional response, reward system, pain perception, energy metabolism and appetite regulation, inflammation, and other biological processes. Genetic variants may be associated with some conditions such as substance/alcohol use disorders, obesity, and eating disorder. The advancement of functional neuroimaging has enabled the evaluation of the neurochemistry of FAAH in brain tissues and this can be incorporated into clinical trials. Intriguingly, the application of FAAH inhibitors in clinical trials seems to provide less striking results in comparison with the animal models, although some potential still can be seen. Conclusion: Modulation of FAAH has an immense potential to be a new therapeutic candidate for several disorders. Further exploration, however, is still needed to ensure who is the best candidate for the treatment strategy.
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Affiliation(s)
- Anugrah D Santoso
- Laboratory of Experimental Urology, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Urology, Faculty of Medicine Universitas Airlangga, Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Dirk De Ridder
- Laboratory of Experimental Urology, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
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5
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Chi ZC. Progress in research of low-grade inflammation in irritable bowel syndrome. Shijie Huaren Xiaohua Zazhi 2022; 30:1051-1065. [DOI: 10.11569/wcjd.v30.i24.1051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a common intestinal disease with a prevalence of 10%-15%. However, its pathophysiology is still not completely clear, and it has long been considered as a functional disease. In recent years, it has been found that low-grade inflammation plays a pathogenic role in IBS. Studies have confirmed that there is persistent mucosal inflammation at the microscopic and molecular levels. This review discusses the evidence, role, and clinical relevance of mucosal inflammation in IBS. In addition to mucosal inflammation, neuroinflammation may lead to changes in neuroendocrine pathways and glucocorticoid receptor genes through the "gut-brain" axis, and thus cause IBS through proinflammatory phenotype and hypothalamic pituitary adrenal axis and 5-hydroxytryptamine dysfunction. The observation that IBS patients can benefit from anti-inflammatory therapy also confirms that IBS is associated with inflammation.
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Affiliation(s)
- Zhao-Chun Chi
- Department of Gastroenterology, Qingdao Municipal Hospital, Qingdao 266011, Shandong Province, China
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6
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Olyaiee A, Sadeghi A, Yadegar A, Mirsamadi ES, Mirjalali H. Gut Microbiota Shifting in Irritable Bowel Syndrome: The Mysterious Role of Blastocystis sp. Front Med (Lausanne) 2022; 9:890127. [PMID: 35795640 PMCID: PMC9251125 DOI: 10.3389/fmed.2022.890127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/09/2022] [Indexed: 11/13/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a chronic disorder, which its causative agent is not completely clear; however, the interaction between microorganisms and gastrointestinal (GI) epithelial cells plays a critical role in the development of IBS and presenting symptoms. During recent decades, many studies have highlighted the high prevalence of Blastocystis sp. in patients with IBS and suggested a probable role for this protist in this disease. Recent studies have documented changes in the gut microbiota composition in patients with IBS regarding the presence of Blastocystis sp., but it is not clear that either disturbance of the gut during GI disorders is a favorable condition for Blastocystis sp. colonization or the presence of this protist may lead to alteration in the gut microbiota in IBS patients. In this review, we comprehensively gather and discuss scientific findings covering the role of Blastocystis sp. in IBS via gut microbiota shifting.
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Affiliation(s)
- Alireza Olyaiee
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Amir Sadeghi
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Yadegar
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Elnaz Sadat Mirsamadi
- Department of Microbiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Hamed Mirjalali
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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7
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Burns GL, Talley NJ, Keely S. Immune responses in the irritable bowel syndromes: time to consider the small intestine. BMC Med 2022; 20:115. [PMID: 35354471 PMCID: PMC8969236 DOI: 10.1186/s12916-022-02301-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/15/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is considered a disorder of gut-brain interaction (DGBI), presenting as chronic abdominal pain and altered defaecation. Symptoms are often food related. Much work in the field has focused on identifying physiological, immune and microbial abnormalities in the colon of patients; however, evidence of small intestinal immune activation and microbial imbalance has been reported in small studies. The significance of such findings has been largely underappreciated despite a growing body of work implicating small intestinal homeostatic imbalance in the pathogenesis of DGBIs. MAIN TEXT Small intestinal mechanosensation is a characteristic feature of IBS. Furthermore, altered small intestinal barrier functions have been demonstrated in IBS patients with the diarrhoea-predominant subtype. Small intestinal bacterial overgrowth and increased populations of small intestinal mast cells are frequently associated with IBS, implicating microbial imbalance and low-grade inflammation in the pathogenesis of IBS. Furthermore, reports of localised food hypersensitivity responses in IBS patients implicate the small intestine as the site of immune-microbial-food interactions. CONCLUSIONS Given the association of IBS symptoms with food intake in a large proportion of patients and the emerging evidence of immune activation in these patients, the current literature suggests the pathogenesis of IBS is not limited to the colon but rather may involve dysfunction of the entire intestinal tract. It remains unclear if regional variation in IBS pathology explains the various symptom phenotypes and further work should consider the intestinal tract as a whole to answer this question.
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Affiliation(s)
- Grace L Burns
- NHMRC Centre of Research Excellence in Digestive Health, The University of Newcastle, Callaghan, New South Wales, Australia.,College of Health, Medicine and Wellbeing, The University of Newcastle, Callaghan, New South Wales, Australia.,Immune Health Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Nicholas J Talley
- NHMRC Centre of Research Excellence in Digestive Health, The University of Newcastle, Callaghan, New South Wales, Australia.,College of Health, Medicine and Wellbeing, The University of Newcastle, Callaghan, New South Wales, Australia.,Immune Health Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Simon Keely
- NHMRC Centre of Research Excellence in Digestive Health, The University of Newcastle, Callaghan, New South Wales, Australia. .,College of Health, Medicine and Wellbeing, The University of Newcastle, Callaghan, New South Wales, Australia. .,Immune Health Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia.
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8
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McPherson ZE, Sørensen HT, Horváth‐Puhó E, Agar A, Coroneo MT, White A, Francis IC, Pasquale LR, Kang JH, Pettersson S, Talley NJ, McEvoy MA. Irritable bowel syndrome and risk of glaucoma: An analysis of two independent population-based cohort studies. United European Gastroenterol J 2021; 9:1057-1065. [PMID: 34431591 PMCID: PMC8598964 DOI: 10.1002/ueg2.12136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 07/03/2021] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Irritable bowel syndrome (IBS) is a chronic disorder associated with an abnormal gastrointestinal microbiome. Microbiome-host interactions are known to influence organ function including in the central nervous system; thus, we sought to identify whether IBS may be a risk factor for the development of glaucoma. DESIGN Two prospective cohort studies. SUBJECTS The 1958 United Kingdom Birth Cohort (UKBC; 9091 individuals) and the Danish National Registry of Patients (DNRP; 62,541 individuals with IBS and 625,410 matched general population cohort members). METHODS In the UKBC, participants were surveyed throughout life (including at ages 42 and 50). The DNRP contains records of hospital-based contacts and prescription data from the national prescription database. MAIN OUTCOME MEASURE The main outcome measure was incidence of glaucoma. In the UKBC, incident glaucoma at age 50 (n = 48) was determined through comparison of survey responses at ages 42 and 50 years. In the DNRP, glaucoma was assessed by hospital diagnosis (n = 1510), glaucoma surgery (n = 582) and initiation of glaucoma medications (n = 1674). RESULTS In the UKBC, the odds ratio (OR) of developing glaucoma between ages 42 and 50 in persons with a chronic IBS diagnosis was increased [OR: 5.84, 95% confidence interval (CI): 2.26-15.13]. People with an IBS diagnosis in the DNRP had a hazard ratio (HR) of 1.35 for developing physician-diagnosed glaucoma (95% CI: 1.16-1.56), an HR of 1.35 for undergoing glaucoma surgery (95% CI: 1.06-1.70) and an HR of 1.19 for initiating glaucoma medication (95% CI: 1.03-1.38). CONCLUSIONS In two large European cohort studies, IBS is a risk factor for glaucoma.
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Affiliation(s)
- Zachary E. McPherson
- School of Medicine and Public HealthThe Centre for Clinical Epidemiology and BiostatisticsThe Australian GastroIntestinal Research Alliance (AGIRA)The University of NewcastleCallaghanNew South WalesAustralia
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingapore
- Rural Health SchoolLa Trobe UniversityBendigo VictoriaAustralia
| | | | | | - Ashish Agar
- Department of OphthalmologyPrince of Wales HospitalRandwickNew South WalesAustralia
| | - Minas T. Coroneo
- Department of OphthalmologyPrince of Wales HospitalRandwickNew South WalesAustralia
- The School of MedicineThe University of New South WalesKensingtonNew South WalesAustralia
| | - Andrew White
- Department of OphthalmologyWestmead HospitalWestmeadNew South WalesAustralia
- Westmead Institute for Medical ResearchUniversity of SydneySydneyNew South WalesAustralia
| | - Ian C. Francis
- Department of OphthalmologyPrince of Wales HospitalRandwickNew South WalesAustralia
- The School of MedicineThe University of New South WalesKensingtonNew South WalesAustralia
| | - Louis R. Pasquale
- Department of OphthalmologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Jae H. Kang
- Channing Division of Network MedicineDepartment of MedicineBrigham & Women's Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Sven Pettersson
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingapore
| | - Nicholas J. Talley
- School of Medicine and Public HealthThe Centre for Clinical Epidemiology and BiostatisticsThe Australian GastroIntestinal Research Alliance (AGIRA)The University of NewcastleCallaghanNew South WalesAustralia
| | - Mark A. McEvoy
- School of Medicine and Public HealthThe Centre for Clinical Epidemiology and BiostatisticsThe Australian GastroIntestinal Research Alliance (AGIRA)The University of NewcastleCallaghanNew South WalesAustralia
- Rural Health SchoolLa Trobe UniversityBendigo VictoriaAustralia
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Wauters L, Ceulemans M, Vanuytsel T. Duodenum at a crossroads: Key integrator of overlapping and psychological symptoms in functional dyspepsia? Neurogastroenterol Motil 2021; 33:e14262. [PMID: 34561921 DOI: 10.1111/nmo.14262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/22/2021] [Accepted: 08/23/2021] [Indexed: 12/20/2022]
Abstract
The study of the interaction between gastrointestinal (GI) function and psychological features is a complex and developing field. The bidirectional communication between the gut and the brain or gut-brain axis is considered as a pivotal player in the pathogenesis of the highly prevalent functional GI disorders, including irritable bowel syndrome and functional dyspepsia (FD), which have been redefined as disorders of gut-brain interaction. However, the mechanisms through which changes in the gut alter brain functioning, feelings, and behavior remain unclear. Based on the presence of duodenal pathology in adult FD patients, Ronkainen et al. provide the first prospective evidence for duodenal eosinophils potentially driving anxiety. Also in this edition, associations between gastroduodenal pathology and rumination syndrome, which may coexist with FD, have now been confirmed in children by Friesen et al. Together these findings confirm not only the potential role of duodenal alterations in determining overlapping upper GI but also psychological symptoms, which result from bidirectional and complex interactions. In this review, we provide an overview of the recent advances in this field and highlight the novel contributions of the original studies of Ronkainen et al. and Friesen et al. to this topic.
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Affiliation(s)
- Lucas Wauters
- Department of Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium.,Translational Research in Gastrointestinal Disorders (TARGID), KU Leuven, Leuven, Belgium
| | - Matthias Ceulemans
- Translational Research in Gastrointestinal Disorders (TARGID), KU Leuven, Leuven, Belgium
| | - Tim Vanuytsel
- Department of Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium.,Translational Research in Gastrointestinal Disorders (TARGID), KU Leuven, Leuven, Belgium
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10
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Videlock EJ, Chang L. Latest Insights on the Pathogenesis of Irritable Bowel Syndrome. Gastroenterol Clin North Am 2021; 50:505-522. [PMID: 34304785 DOI: 10.1016/j.gtc.2021.04.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The pathogenesis of irritable bowel syndrome is multifactorial and complex. Our understanding of its pathophysiology has evolved, but remains incompletely understood. Symptoms result from a dysregulation of brain-gut interactions. Evidence has identified alterations in central and peripheral (gut) mechanisms in irritable bowel syndrome and the bidirectional communication between the brain and the gut. Pertinent mechanisms include disturbed gut motility, visceral hypersensitivity, altered mucosal and immune function, altered gut microbiota, and altered central nervous system processing. This review addresses factors that increase the risk of irritable bowel syndrome and the central and peripheral mechanisms thought to underlie its symptoms.
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Affiliation(s)
- Elizabeth J Videlock
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Lin Chang
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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11
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Carco C, Young W, Gearry RB, Talley NJ, McNabb WC, Roy NC. Increasing Evidence That Irritable Bowel Syndrome and Functional Gastrointestinal Disorders Have a Microbial Pathogenesis. Front Cell Infect Microbiol 2020; 10:468. [PMID: 33014892 PMCID: PMC7509092 DOI: 10.3389/fcimb.2020.00468] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/29/2020] [Indexed: 12/12/2022] Open
Abstract
The human gastrointestinal tract harbors most of the microbial cells inhabiting the body, collectively known as the microbiota. These microbes have several implications for the maintenance of structural integrity of the gastrointestinal mucosal barrier, immunomodulation, metabolism of nutrients, and protection against pathogens. Dysfunctions in these mechanisms are linked to a range of conditions in the gastrointestinal tract, including functional gastrointestinal disorders, ranging from irritable bowel syndrome, to functional constipation and functional diarrhea. Irritable bowel syndrome is characterized by chronic abdominal pain with changes in bowel habit in the absence of morphological changes. Despite the high prevalence of irritable bowel syndrome in the global population, the mechanisms responsible for this condition are poorly understood. Although alterations in the gastrointestinal microbiota, low-grade inflammation and immune activation have been implicated in the pathophysiology of functional gastrointestinal disorders, there is inconsistency between studies and a lack of consensus on what the exact role of the microbiota is, and how changes to it relate to these conditions. The complex interplay between host factors, such as microbial dysbiosis, immune activation, impaired epithelial barrier function and motility, and environmental factors, including diet, will be considered in this narrative review of the pathophysiology of functional gastrointestinal disorders.
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Affiliation(s)
- Caterina Carco
- School of Food and Advanced Technology, Massey University, Palmerston North, New Zealand.,Riddet Institute, Massey University, Palmerston North, New Zealand.,Food Nutrition and Health Team, AgResearch Grasslands, Palmerston North, New Zealand.,The High-Value Nutrition National Science Challenge, Auckland, New Zealand
| | - Wayne Young
- Riddet Institute, Massey University, Palmerston North, New Zealand.,Food Nutrition and Health Team, AgResearch Grasslands, Palmerston North, New Zealand.,The High-Value Nutrition National Science Challenge, Auckland, New Zealand
| | - Richard B Gearry
- The High-Value Nutrition National Science Challenge, Auckland, New Zealand.,Department of Medicine, University of Otago, Christchurch, New Zealand
| | - Nicholas J Talley
- Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia
| | - Warren C McNabb
- Riddet Institute, Massey University, Palmerston North, New Zealand.,The High-Value Nutrition National Science Challenge, Auckland, New Zealand
| | - Nicole C Roy
- Riddet Institute, Massey University, Palmerston North, New Zealand.,The High-Value Nutrition National Science Challenge, Auckland, New Zealand.,Liggins Institute, University of Auckland, Auckland, New Zealand.,Department of Human Nutrition, University of Otago, Dunedin, New Zealand
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12
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Kamp KJ, Han C, Shulman RJ, Cain KC, Barney P, Opp MR, Chang L, Burr RL, Heitkemper MM. Cytokine Levels and Symptoms Among Women with Irritable Bowel Syndrome: Considering the Role of Hormonal Contraceptive Use. Biol Res Nurs 2020; 23:171-179. [PMID: 32677464 DOI: 10.1177/1099800420941252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Young to middle-aged women are more likely than men to be diagnosed with irritable bowel syndrome (IBS). Immune dysfunction may be present in IBS, however, few studies have tested whether hormonal contraceptive use is linked to inflammatory markers. The purpose of this study was to compare cytokine levels between women (ages 18-45) with and without IBS and with and without hormonal contraceptive use and to examine the relationships of cytokine levels to IBS gastrointestinal (GI) and non-GI symptoms within those using and not using hormonal contraceptives. METHODS Seventy-three women with IBS and 47 healthy control women completed questionnaires (demographics, hormonal contraceptive use) and kept a 28-day symptom diary. Fasting plasma and LPS-stimulated pro-inflammatory (IL-1β, IL-6, IL-12p40, IL-12p70, IL-8, and TNF-α) and anti-inflammatory (IL-10) cytokines were assayed. RESULTS No differences were found in plasma or stimulated cytokine levels between IBS and control women. Levels of IL-1β (p = 0.04) and TNF-α (p = 0.02) were higher among women who did not use hormonal contraceptives compared to women who used hormonal contraceptives. Among women with IBS, significant correlations were found between daily psychological distress and plasma IL-10, IL-12p70, IL-1β, IL-6, and IL-8 cytokine levels. CONCLUSIONS These results suggest that hormonal contraceptive use might reduce IL-1β and TNF-α cytokine levels in women with IBS. The impact of hormonal contraceptive use on innate immune activation among women with IBS requires further research.
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Affiliation(s)
| | - Claire Han
- 7284University of Washington, Seattle, WA, USA
| | | | | | | | - Mark R Opp
- 1878University of Colorado, Boulder, CO, USA
| | - Lin Chang
- 8783University of California, Los Angeles, CA, USA
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13
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Casado-Bedmar M, Keita ÅV. Potential neuro-immune therapeutic targets in irritable bowel syndrome. Therap Adv Gastroenterol 2020; 13:1756284820910630. [PMID: 32313554 PMCID: PMC7153177 DOI: 10.1177/1756284820910630] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 02/11/2020] [Indexed: 02/04/2023] Open
Abstract
Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder characterized by recurring abdominal pain and disturbed bowel habits. The aetiology of IBS is unknown but there is evidence that genetic, environmental and immunological factors together contribute to the development of the disease. Current treatment of IBS includes lifestyle and dietary interventions, laxatives or antimotility drugs, probiotics, antispasmodics and antidepressant medication. The gut-brain axis comprises the central nervous system, the hypothalamic pituitary axis, the autonomic nervous system and the enteric nervous system. Within the intestinal mucosa there are close connections between immune cells and nerve fibres of the enteric nervous system, and signalling between, for example, mast cells and nerves has shown to be of great importance during GI disorders such as IBS. Communication between the gut and the brain is most importantly routed via the vagus nerve, where signals are transmitted by neuropeptides. It is evident that IBS is a disease of a gut-brain axis dysregulation, involving altered signalling between immune cells and neurotransmitters. In this review, we analyse the most novel and distinct neuro-immune interactions within the IBS mucosa in association with already existing and potential therapeutic targets.
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Affiliation(s)
- Maite Casado-Bedmar
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Åsa V. Keita
- Department of Biomedical and Clinical Sciences, Medical Faculty, Linköping University, Campus US, Linköping, 581 85, Sweden
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Andrews CN, Sidani S, Marshall JK. Clinical Management of the Microbiome in Irritable Bowel Syndrome. J Can Assoc Gastroenterol 2020; 4:36-43. [PMID: 33644675 PMCID: PMC7898379 DOI: 10.1093/jcag/gwz037] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 11/15/2019] [Indexed: 12/11/2022] Open
Abstract
Background A growing body of evidence suggests that dysbiosis contributes to the onset and symptomatology of irritable bowel syndrome (IBS) and other functional bowel disorders. Changes to the gastrointestinal microbiome may contribute to the underlying pathophysiology of IBS. Methods The present review summarizes the potential effects of microbiome changes on GI transit, intestinal barrier function, immune dysregulation and inflammation, gut–brain interactions and neuropsychiatric function. Results A multimodal approach to IBS management is recommended in accordance with current Canadian guidelines. Pharmacologic treatments are advised to target the presumed underlying pathophysiological mechanism, such as dysregulation of GI transit, peristalsis, intestinal barrier function and pain signalling. The management plan for IBS may also include treatments directed at dysbiosis, including dietary modification and use of probiotics, which may promote the growth of beneficial bacteria, affect intestinal gas production and modulate the immune response; and the administration of periodic short courses of a nonsystemic antibiotic such as rifaximin, which may re-establish microbiota diversity and improve IBS symptoms. Conclusion Dysregulated host–microbiome interactions are complex and the use of microbiome-directed therapies will necessarily be empiric in individual patients. A management algorithm comprising microbiome- and nonmicrobiome-directed therapies is proposed.
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Affiliation(s)
- Christopher N Andrews
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sacha Sidani
- Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - John K Marshall
- Department of Medicine and Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
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Nilholm C, Roth B, Ohlsson B. A Dietary Intervention with Reduction of Starch and Sucrose Leads to Reduced Gastrointestinal and Extra-Intestinal Symptoms in IBS Patients. Nutrients 2019; 11:nu11071662. [PMID: 31330810 PMCID: PMC6682926 DOI: 10.3390/nu11071662] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/12/2019] [Accepted: 07/17/2019] [Indexed: 12/12/2022] Open
Abstract
Patients with irritable bowel syndrome (IBS) exhibit low-grade inflammation and increased gut permeability. Dietary sugar has been shown to contribute to low-grade inflammation and increased gut permeability, and to correlate with gastrointestinal (GI) symptoms. The aim of the present study was to examine the effect of a starch- and sucrose-reduced diet (SSRD) on gastrointestinal (GI) and extra-intestinal symptoms in IBS. One hundred and five IBS patients (82 women, 46.06 ± 13.11 years), with irritable bowel syndrome-symptom severity scale (IBS-SSS) > 175, were randomized to SSRD for 4 weeks or continued ordinary eating habits. The visual analog scale for irritable bowel syndrome (VAS-IBS), IBS-SSS, and 4-day food diaries were collected at baseline and after 2 and 4 weeks. After the intervention, one-third of the patients did not fulfill the criteria for IBS/functional gastrointestinal disorder. Half of the participants changed from moderate/severe disease to no/mild disease according to IBS-SSS. Comparisons between the groups showed decreased weight and sweet cravings, and parallel decreases in total IBS-SSS and extra-intestinal IBS-SSS scores, in the intervention group compared to controls (p < 0.001 for all). When calculating separate extra-intestinal symptoms, belching (p = 0.001), muscle/joint pain (p = 0.029), urinary urgency (p = 0.017), and tiredness (p = 0.011) were decreased after introduction of SSRD compared to controls. In conclusion, SSRD improves both GI and extra-intestinal symptoms in IBS.
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Affiliation(s)
- Clara Nilholm
- Department of Internal Medicine, Lund University, Skåne University Hospital, 205 02 Malmö, Sweden
| | - Bodil Roth
- Department of Internal Medicine, Lund University, Skåne University Hospital, 205 02 Malmö, Sweden
| | - Bodil Ohlsson
- Department of Internal Medicine, Lund University, Skåne University Hospital, 205 02 Malmö, Sweden.
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