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Barbara G, Cremon C, Annese V, Basilisco G, Bazzoli F, Bellini M, Benedetti A, Benini L, Bossa F, Buldrini P, Cicala M, Cuomo R, Germanà B, Molteni P, Neri M, Rodi M, Saggioro A, Scribano ML, Vecchi M, Zoli G, Corinaldesi R, Stanghellini V. Randomised controlled trial of mesalazine in IBS. Gut 2016; 65:82-90. [PMID: 25533646 PMCID: PMC4717362 DOI: 10.1136/gutjnl-2014-308188] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 11/20/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Low-grade intestinal inflammation plays a role in the pathophysiology of IBS. In this trial, we aimed at evaluating the efficacy and safety of mesalazine in patients with IBS. DESIGN We conducted a phase 3, multicentre, tertiary setting, randomised, double-blind, placebo-controlled trial in patients with Rome III confirmed IBS. Patients were randomly assigned to either mesalazine, 800 mg, or placebo, three times daily for 12 weeks, and were followed for additional 12 weeks. The primary efficacy endpoint was satisfactory relief of abdominal pain/discomfort for at least half of the weeks of the treatment period. The key secondary endpoint was satisfactory relief of overall IBS symptoms. Supportive analyses were also performed classifying as responders patients with a percentage of affirmative answers of at least 75% or >75% of time. RESULTS A total of 185 patients with IBS were enrolled from 21 centres. For the primary endpoint, the responder patients were 68.6% in the mesalazine group versus 67.4% in the placebo group (p=0.870; 95% CI -12.8 to 15.1). In explorative analyses, with the 75% rule or >75% rule, the percentage of responders was greater in the mesalazine group with a difference over placebo of 11.6% (p=0.115; 95% CI -2.7% to 26.0%) and 5.9% (p=0.404; 95% CI -7.8% to 19.4%), respectively, although these differences were not significant. For the key secondary endpoint, overall symptoms improved in the mesalazine group and reached a significant difference of 15.1% versus placebo (p=0.032; 95% CI 1.5% to 28.7%) with the >75% rule. CONCLUSIONS Mesalazine treatment was not superior than placebo on the study primary endpoint. However, a subgroup of patients with IBS showed a sustained therapy response and benefits from a mesalazine therapy. TRIAL REGISTRATION NUMBER ClincialTrials.gov number, NCT00626288.
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Affiliation(s)
- Giovanni Barbara
- Department of Medical and Surgical Sciences, Centre for Applied Biomedical Research, University of Bologna, Bologna, Italy
| | - Cesare Cremon
- Department of Medical and Surgical Sciences, Centre for Applied Biomedical Research, University of Bologna, Bologna, Italy
| | - Vito Annese
- Division of Gastroenterology SOD2, University Hospital Careggi, Florence, Italy
| | - Guido Basilisco
- Gastroenterology Unit, Ospedale Maggiore, Policlinico, Milan, Italy
| | - Franco Bazzoli
- Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Massimo Bellini
- Gastroenterology Unit, Department of Gastroenterology, University of Pisa, Pisa, Italy
| | - Antonio Benedetti
- Department of Gastroenterology and Hepatology, Università Politecnica delle Marche, Ancona, Italy
| | - Luigi Benini
- Gastroenterology Unit, University of Verona, Verona, Italy
| | - Fabrizio Bossa
- Division of Gastroenterology, Casa Sollievo Sofferenza Hospital, IRCCS, San Giovanni Rotondo, Italy
| | - Paola Buldrini
- Gastroenterology Unit of Comacchio/Lagosanto, Ferrara, Italy
| | - Michele Cicala
- Gastroenterology Unit, University Campus Bio-Medico of Rome, Rome, Italy
| | - Rosario Cuomo
- Digestive Motility Diseases, Department of Clinical Medicine and Surgery, Federico II University Hospital, Naples, Italy
| | | | - Paola Molteni
- Gastroenterology Unit, Department of Clinical Science, "L. Sacco" University Hospital, Milan, Italy
| | - Matteo Neri
- Department of Medicine and Aging Sciences and CESI, G. D'Annunzio University and Foundation, Chieti, Italy
| | - Marcello Rodi
- Gastroenterology Unit, St. Andrea Hospital, Vercelli, Italy
| | - Alfredo Saggioro
- Department of Digestive Diseases, Hepatology and Clinical Nutrition, Dell'Angelo Hospital, Venice, Italy
| | | | - Maurizio Vecchi
- Gastroenterology and Digestive Endoscopy Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | | | - Roberto Corinaldesi
- Department of Medical and Surgical Sciences, Centre for Applied Biomedical Research, University of Bologna, Bologna, Italy
| | - Vincenzo Stanghellini
- Department of Medical and Surgical Sciences, Centre for Applied Biomedical Research, University of Bologna, Bologna, Italy
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152
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Wouters MM, Vicario M, Santos J. The role of mast cells in functional GI disorders. Gut 2016; 65:155-68. [PMID: 26194403 DOI: 10.1136/gutjnl-2015-309151] [Citation(s) in RCA: 222] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 06/30/2015] [Indexed: 02/06/2023]
Abstract
Functional gastrointestinal disorders (FGIDs) are characterized by chronic complaints arising from disorganized brain-gut interactions leading to dysmotility and hypersensitivity. The two most prevalent FGIDs, affecting up to 16-26% of worldwide population, are functional dyspepsia and irritable bowel syndrome. Their etiopathogenic mechanisms remain unclear, however, recent observations reveal low-grade mucosal inflammation and immune activation, in association with impaired epithelial barrier function and aberrant neuronal sensitivity. These findings come to challenge the traditional view of FGIDs as pure functional disorders, and relate the origin to a tangible organic substrate. The mucosal inflammatory infiltrate is dominated by mast cells, eosinophils and intraepithelial lymphocytes in the intestine of FGIDs. It is well established that mast cell activation can generate epithelial and neuro-muscular dysfunction and promote visceral hypersensitivity and altered motility patterns in FGIDs, postoperative ileus, food allergy and inflammatory bowel disease. This review will discuss the role of mucosal mast cells in the gastrointestinal tract with a specific focus on recent advances in disease mechanisms and clinical management in irritable bowel syndrome and functional dyspepsia.
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Affiliation(s)
- Mira M Wouters
- Translational Research Center for Gastrointestinal Disorders (TARGID), University Hospital Leuven, Leuven, Belgium
| | - Maria Vicario
- Neuro-immuno-gastroenterology Laboratory, Digestive Diseases Research Unit. Vall d'Hebron Institut de Recerca, Department of Gastroenterology, Hospital Universitari Vall d'Hebron & Facultat de Medicina, Universitat Autònoma de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Javier Santos
- Neuro-immuno-gastroenterology Laboratory, Digestive Diseases Research Unit. Vall d'Hebron Institut de Recerca, Department of Gastroenterology, Hospital Universitari Vall d'Hebron & Facultat de Medicina, Universitat Autònoma de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
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153
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Campaniello MA, Harrington AM, Martin CM, Ashley Blackshaw L, Brierley SM, Hughes PA. Activation of colo-rectal high-threshold afferent nerves by Interleukin-2 is tetrodotoxin-sensitive and upregulated in a mouse model of chronic visceral hypersensitivity. Neurogastroenterol Motil 2016; 28:54-63. [PMID: 26468044 DOI: 10.1111/nmo.12696] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 09/02/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Chronic visceral pain is a defining feature of irritable bowel syndrome (IBS). IBS patients often show alterations in innate and adaptive immune function which may contribute to symptoms. Immune mediators are known to modulate the activity of viscero-sensory afferent nerves, but the focus has been on the innate immune system. Interleukin-2 (IL-2) is primarily associated with adaptive immune responses but its effects on colo-rectal afferent function in health or disease are unknown. METHODS Myeloperoxidase (MPO) activity determined the extent of inflammation in health, acute trinitrobenzene-sulfonic acid (TNBS) colitis, and in our post-TNBS colitis model of chronic visceral hypersensitivity (CVH). The functional effects of IL-2 on high-threshold colo-rectal afferents and the expression of IL-2R and NaV 1.7 mRNA in colo-rectal dorsal root ganglia (DRG) neurons were compared between healthy and CVH mice. KEY RESULTS MPO activity was increased during acute colitis, but subsided to levels comparable to health in CVH mice. IL-2 caused direct excitation of colo-rectal afferents that was blocked by tetrodotoxin. IL-2 did not affect afferent mechanosensitivity in health or CVH. However, an increased proportion of afferents responded directly to IL-2 in CVH mice compared with controls (73% vs 33%; p < 0.05), and the abundance of IL-2R and NaV 1.7 mRNA was increased 3.5- and 2-fold (p < 0.001 for both) in colo-rectal DRG neurons. CONCLUSIONS & INFERENCES IL-2, an immune mediator from the adaptive arm of the immune response, affects colo-rectal afferent function, indicating these effects are not restricted to innate immune mediators. Colo-rectal afferent sensitivity to IL-2 is increased long after healing from inflammation.
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Affiliation(s)
- M A Campaniello
- Centre for Nutritional and Gastrointestinal Diseases, Department of Medicine, University of Adelaide and South Australian Health Medical Health Research Institute, Adelaide, SA, Australia
| | - A M Harrington
- Centre for Nutritional and Gastrointestinal Diseases, Department of Medicine, University of Adelaide and South Australian Health Medical Health Research Institute, Adelaide, SA, Australia
| | - C M Martin
- Centre for Nutritional and Gastrointestinal Diseases, Department of Medicine, University of Adelaide and South Australian Health Medical Health Research Institute, Adelaide, SA, Australia
| | - L Ashley Blackshaw
- Neurogastroenterology Group, Blizard Institute, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
| | - S M Brierley
- Centre for Nutritional and Gastrointestinal Diseases, Department of Medicine, University of Adelaide and South Australian Health Medical Health Research Institute, Adelaide, SA, Australia
| | - P A Hughes
- Centre for Nutritional and Gastrointestinal Diseases, Department of Medicine, University of Adelaide and South Australian Health Medical Health Research Institute, Adelaide, SA, Australia
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154
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Advanced 3D Optical Microscopy in ENS Research. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 891:193-9. [DOI: 10.1007/978-3-319-27592-5_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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155
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Lam C, Tan W, Leighton M, Hastings M, Lingaya M, Falcone Y, Zhou X, Xu L, Whorwell P, Walls AF, Zaitoun A, Montgomery A, Spiller R. A mechanistic multicentre, parallel group, randomised placebo-controlled trial of mesalazine for the treatment of IBS with diarrhoea (IBS-D). Gut 2016; 65:91-9. [PMID: 25765462 PMCID: PMC4717357 DOI: 10.1136/gutjnl-2015-309122] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 02/03/2015] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Immune activation has been reported in the mucosa of IBS patients with diarrhoea (IBS-D), and some small studies have suggested that mesalazine may reduce symptoms. We performed a double-blind, randomised placebo-controlled trial of 2 g mesalazine twice daily versus placebo for 3 months in patients with Rome III criteria IBS-D. Primary outcome was daily average stool frequency during weeks 11-12; secondary outcomes were abdominal pain, stool consistency, urgency and satisfactory relief of IBS symptoms. METHODS Participants were randomised after a 2-week baseline stool diary. All participants completed a 12-week stool diary and at the end of each week recorded the presence of 'satisfactory relief of IBS symptoms'. RESULTS 136 patients with IBS-D (82 women, 54 men) were randomised, 10 patients withdrew from each group. Analysis by intention to treat showed the daily average stool frequency during weeks 11 and 12 were mean (SD), 2.8 (1.2) in mesalazine and 2.7 (1.9) in the placebo group with no significant group difference, (95% CI) 0.1 (-0.33 to 0.53), p=0.66. Mesalazine did not improve abdominal pain, stool consistency nor percentage with satisfactory relief compared with placebo during the last two-weeks follow-up. CONCLUSIONS This study does not support any clinically meaningful benefit or harm of mesalazine compared with placebo in unselected patients with IBS-D. More precise subtyping based on underlying disease mechanisms is needed to allow more effective targeting of treatment in IBS. TRIAL REGISTRATION NUMBER NCT01316718.
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Affiliation(s)
- Ching Lam
- NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, UK
| | - Wei Tan
- Nottingham Clinical Trials Unit, University of Nottingham, Nottingham, UK
| | - Matthew Leighton
- Nottingham Clinical Trials Unit, University of Nottingham, Nottingham, UK
| | | | - Melanie Lingaya
- NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, UK
| | - Yirga Falcone
- NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, UK
| | - Xiaoying Zhou
- Immunopharmacology Group, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Luting Xu
- FRAME laboratory, University of Nottingham, Nottingham, UK
| | - Peter Whorwell
- Neurogastroenterology Unit, Wythenshawe Hospital, Manchester, UK
| | - Andrew F Walls
- Immunopharmacology Group, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Abed Zaitoun
- Department of Histopathology, Nottingham University Hospital Trusts, Nottingham, UK
| | - Alan Montgomery
- Nottingham Clinical Trials Unit, University of Nottingham, Nottingham, UK
| | - Robin Spiller
- NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, UK
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156
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Aich A, Afrin LB, Gupta K. Mast Cell-Mediated Mechanisms of Nociception. Int J Mol Sci 2015; 16:29069-92. [PMID: 26690128 PMCID: PMC4691098 DOI: 10.3390/ijms161226151] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 11/28/2015] [Accepted: 12/01/2015] [Indexed: 12/12/2022] Open
Abstract
Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner.
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Affiliation(s)
- Anupam Aich
- Vascular Biology Center, Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Lawrence B Afrin
- Vascular Biology Center, Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Kalpna Gupta
- Vascular Biology Center, Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
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157
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Evidence for neuronal and structural changes in submucous ganglia of patients with functional dyspepsia. Am J Gastroenterol 2015; 110:1205-15. [PMID: 26077177 DOI: 10.1038/ajg.2015.158] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 04/02/2015] [Indexed: 02/07/2023]
Abstract
OBJECTIVES An intact and well-functioning enteric nervous system is necessary to efficiently organize gut function. Functional gastrointestinal disorders are pathological entities in which gut function is impaired without a clearly established pathophysiology. On the basis of the relative ease with which intestinal biopsies can be obtained, and taking advantage of a recently developed optical recording technique, we evaluated whether functional neuronal defects exist in enteric nerves of patients with functional dyspepsia (FD). METHODS The submucous plexus isolated from duodenal biopsies taken from FD patients and control subjects was used to functionally and morphologically examine nerves and ganglionic architecture (neurons and glial cells). In light of previous studies reporting eosinophil and mast cell infiltration in the gut mucosa of FD patients, we also examined whether these cells infiltrated the submucous plexus and whether this correlated with neuronal activity and specific clinical symptoms. RESULTS We demonstrate that neuronal functioning is impaired in the submucous plexus of FD patients, as shown by decreased calcium responses to depolarization and electrical stimulation. Glial (S100) and neuronal (HuCD) markers show signs of gliosis, altered ganglionic architecture, and neuronal abnormalities in the submucous plexus of FD patients. We found that eosinophils and mast cells infiltrated the submucous layer of FD patients to a much larger extent than in controls. A significant correlation was found between the number of these cells and the calcium transient amplitudes measured in submucous ganglia. CONCLUSIONS We provide the first direct evidence that FD is characterized by functional and structural abnormalities within the submucous ganglion plexus, which may be of future predictive and diagnostic value in the treatment of FD patients.
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158
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Chira A, Dumitrascu DL. Serum biomarkers for irritable bowel syndrome. ACTA ACUST UNITED AC 2015; 88:258-64. [PMID: 26609254 PMCID: PMC4632880 DOI: 10.15386/cjmed-496] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 06/30/2015] [Indexed: 12/15/2022]
Abstract
Background and aim Irritable bowel syndrome (IBS) is one of the most frequent and common functional gastrointestinal diseases. For its diagnosis, clinical criteria are still used. Our objective was to asses if there are specific serum biomarkers for the diagnosis of IBS, and as secondary purpose we aimed to analyze the specificity and sensitivity – where determined – for the proposed biomarkers. Methods We performed a review in order to find potential serum biomarkers useful for the diagnosis of IBS. MEDLINE and Cochrane databases were searched in May 2015. Inclusion criteria were: original studies that assessed serological markers in IBS patients, markers potentially useful for diagnosing IBS or in differentiating subtypes of IBS. Exclusion criteria were biomarkers assessed in IBS patients not for the diagnosis of IBS, but used in order to exclude other conditions or diseases in these patients; or markers that were not addressed to IBS; or papers that assessed only fecal biomarkers, or histological or surrogate - indirect biomarkers. Results From the 268 papers retrieved by our initial search, using a modified strategy we identified 58 papers. Out of the 58 papers retrieved by the search, six papers were selected and other nine studies were eventually analyzed. Of the results of the computerized search, a number of papers were not included for various reasons: some were not related to the subject (26), others were not appropriate for the subject (19) because they addressed inflammatory bowel disorders, in others fecal markers were the subject of the study, six were reviews, others were impossible to gain access to (1). Twelve out of the 14 studies included are case-control studies, IBS diagnosis being established in all of the selected results based on the Rome criteria. A higher sensitivity of 81% was found using a combination of markers but with lower specificity, while one study that assessed also a combination of markers, found a higher specificity but sensitivity was only 50 %; none reached the characteristics for an ideal biomarker. Conclusions For the moment, just one serum biomarker with a high specificity and sensitivity useful in the diagnosis of IBS was identified. We consider that in the future a combination of several biomarkers could better identify IBS than a single biomarker. Therefore, clinical criteria are still to be used for the diagnosis of IBS in attendance for newer research or validation of results.
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Affiliation(s)
- Alexandra Chira
- 2nd Medical Department, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Dan Lucian Dumitrascu
- 2nd Medical Department, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
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159
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Boesmans W, Hao MM, Vanden Berghe P. Optical Tools to Investigate Cellular Activity in the Intestinal Wall. J Neurogastroenterol Motil 2015; 21:337-51. [PMID: 26130630 PMCID: PMC4496899 DOI: 10.5056/jnm15096] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 06/10/2015] [Indexed: 12/13/2022] Open
Abstract
Live imaging has become an essential tool to investigate the coordinated activity and output of cellular networks. Within the last decade, 2 Nobel prizes have been awarded to recognize innovations in the field of imaging: one for the discovery, use, and optimization of the green fluorescent protein (2008) and the second for the development of super-resolved fluorescence microscopy (2014). New advances in both optogenetics and microscopy now enable researchers to record and manipulate activity from specific populations of cells with better contrast and resolution, at higher speeds, and deeper into live tissues. In this review, we will discuss some of the recent developments in microscope technology and in the synthesis of fluorescent probes, both synthetic and genetically encoded. We focus on how live imaging of cellular physiology has progressed our understanding of the control of gastrointestinal motility, and we discuss the hurdles to overcome in order to apply the novel tools in the field of neurogastroenterology and motility.
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Affiliation(s)
- Werend Boesmans
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for GastroIntestinal Disorders (TARGID), Department of Clinical and Experimental Medicine, University of Leuven, Leuven, Belgium
| | - Marlene M Hao
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for GastroIntestinal Disorders (TARGID), Department of Clinical and Experimental Medicine, University of Leuven, Leuven, Belgium
| | - Pieter Vanden Berghe
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for GastroIntestinal Disorders (TARGID), Department of Clinical and Experimental Medicine, University of Leuven, Leuven, Belgium
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160
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O’Malley D. Immunomodulation of enteric neural function in irritable bowel syndrome. World J Gastroenterol 2015; 21:7362-7366. [PMID: 26139983 PMCID: PMC4481432 DOI: 10.3748/wjg.v21.i24.7362] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 02/03/2015] [Accepted: 03/12/2015] [Indexed: 02/06/2023] Open
Abstract
Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder which is characterised by symptoms such as bloating, altered bowel habit and visceral pain. It’s generally accepted that miscommunication between the brain and gut underlies the changes in motility, absorpto-secretory function and pain sensitivity associated with IBS. However, partly due to the lack of disease-defining biomarkers, understanding the aetiology of this complex and multifactorial disease remains elusive. Anecdotally, IBS patients have noted that periods of stress can result in symptom flares and many patients exhibit co-morbid stress-related mood disorders such as anxiety and depression. However, in addition to psychosocial stressors, infection-related stress has also been linked with the initiation, persistence and severity of symptom flares. Indeed, prior gastrointestinal infection is one of the strongest predictors of developing IBS. Despite a lack of overt morphological inflammation, the importance of immune factors in the pathophysiology of IBS is gaining acceptance. Subtle changes in the numbers of mucosal immune cell infiltrates and elevated levels of circulating pro-inflammatory cytokines have been reproducibly demonstrated in IBS populations. Moreover, these immune mediators directly affect neural signalling. An exciting new area of research is the role of luminal microbiota in the modulation of neuro-immune signalling, resulting in local changes in gastrointestinal function and alterations in central neural functioning. Progress in this area has begun to unravel some of the complexities of neuroimmune and neuroendocrine interactions and how these molecular exchanges contribute to GI dysfunction
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161
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Camilleri M. Intestinal secretory mechanisms in irritable bowel syndrome-diarrhea. Clin Gastroenterol Hepatol 2015; 13:1051-7; quiz e61-2. [PMID: 25041862 PMCID: PMC4297594 DOI: 10.1016/j.cgh.2014.07.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 07/01/2014] [Accepted: 07/07/2014] [Indexed: 02/07/2023]
Abstract
Although diarrhea is the predominant bowel dysfunction in as many as one-third of patients with irritable bowel syndrome (IBS), it is unclear whether there is a specific disorder of intestinal fluid or electrolyte secretion in IBS. Diarrhea is generally considered a result of accelerated colonic transit in patients with IBS. Although a primary secretory diathesis has not been well-documented in patients with IBS with diarrhea (IBS-D), several mechanisms that could potentially contribute to intestinal secretion have been reported. Some of these mechanisms also influence motor and secretory dysfunctions that contribute to the pathophysiology of IBS-D. We review the evidence supporting secretion in IBS-D caused by peptides and amines produced by enteroendocrine cells or submucosal neurons, enterocyte secretory processes, and intraluminal factors (bile acids and short-chain fatty acids). Understanding these mechanisms and developing clinical methods for their identification could improve management of patients with IBS-D.
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Affiliation(s)
- Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.), Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, Minnesota.
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162
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van Diest SA, van den Elsen LWJ, Klok AJ, Welting O, Hilbers FW, van de Heijning BJ, Gaemers IC, Boeckxstaens GE, Werner MF, Willemsen LEM, de Jonge WJ, van den Wijngaard RM. Dietary Marine n-3 PUFAs Do Not Affect Stress-Induced Visceral Hypersensitivity in a Rat Maternal Separation Model. J Nutr 2015; 145:915-22. [PMID: 25716554 DOI: 10.3945/jn.114.201731] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 02/04/2015] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Although never evaluated for efficacy, n-3 (ω-3) long-chain polyunsaturated fatty acids (LCPUFAs) are commercially offered as treatment for irritable bowel syndrome (IBS). OBJECTIVE This study was designed to investigate, in a mast cell-dependent model for visceral hypersensitivity, whether this pathophysiologic mechanism can be reversed by dietary LCPUFA treatment via peroxisome proliferator-activated receptor γ (PPARG) activation. METHODS Maternally separated rats were subjected to hypersensitivity-inducing acute stress at adult age. Reversal was attempted by protocols with tuna oil-supplemented diets [4% soy oil (SO) and 3% tuna oil (SO-T3) or 3% SO and 7% tuna oil (SO-T7)] and compared with control SO diets (7% or 10% SO) 4 wk after stress. The PPARG agonist rosiglitazone was evaluated in a 1 wk preventive protocol (30 mg · kg⁻¹ · d⁻¹). Erythrocytes were assessed to confirm LCPUFA uptake and tissue expression of lipoprotein lipase and glycerol kinase as indicators of PPARG activation. Colonic mast cell degranulation was evaluated by toluidine blue staining. In vitro, human mast cell line 1 (HMC-1) cells were pretreated with rosiglitazone, eicosapentaenoic acid, or docosahexaenoic acid, stimulated with phorbol 12-myristate 13-acetate (PMA) and calcium ionophore or compound 48/80 and evaluated for tumor necrosis factor α (TNF-α) and β-hexosaminidase release. RESULTS Stress led to visceral hypersensitivity in all groups. Hypersensitivity was not reversed by SO-T3 or control treatment [prestress vs. 24 h poststress vs. posttreatment area under the curve; 76 ± 4 vs. 128 ± 12 (P < 0.05) vs. 115 ± 14 and 82 ± 5 vs. 127 ± 16 (P < 0.01) vs. 113 ± 19, respectively]. Comparison of SO-T7 with its control showed similar results [74 ± 6 vs. 103 ± 13 (P < 0.05) vs. 115 ± 17 and 66 ± 3 vs. 103 ± 10 (P < 0.05) vs. 117 ± 11, respectively]. Erythrocytes showed significant LCPUFA uptake in the absence of colonic PPARG activation. Rosiglitazone induced increased PPARG target gene expression, but did not prevent hypersensitivity. Mast cell degranulation never differed between groups. Rosiglitazone and LCPUFAs significantly reduced PMA/calcium ionophore-induced TNF-α release but not degranulation of HMC-1 cells. CONCLUSION Dietary LCPUFAs did not reverse stress-induced visceral hypersensitivity in maternally separated rats. Although further research is needed, claims concerning LCPUFAs as a treatment option in IBS cannot be confirmed at this point and should be regarded with caution.
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Affiliation(s)
- Sophie A van Diest
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Lieke W J van den Elsen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Allison J Klok
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Olaf Welting
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Francisca W Hilbers
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | | | - Ingrid C Gaemers
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Guy E Boeckxstaens
- Division of Gastroenterology, University Hospital Gasthuisberg, University of Leuven, Leuven, Belgium; and
| | - Maria F Werner
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, Brazil
| | - Linette E M Willemsen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Wouter J de Jonge
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - René M van den Wijngaard
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands;
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163
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Dothel G, Barbaro MR, Boudin H, Vasina V, Cremon C, Gargano L, Bellacosa L, De Giorgio R, Le Berre-Scoul C, Aubert P, Neunlist M, De Ponti F, Stanghellini V, Barbara G. Nerve fiber outgrowth is increased in the intestinal mucosa of patients with irritable bowel syndrome. Gastroenterology 2015; 148:1002-1011.e4. [PMID: 25655556 DOI: 10.1053/j.gastro.2015.01.042] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 01/24/2015] [Accepted: 01/27/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Mediators released by the intestinal mucosa of patients with irritable bowel syndrome (IBS) affect the function of enteric and extrinsic sensory nerves, which can contribute to the development of symptoms. Little is known about the effects of mucosal mediators on intestinal neuroplasticity. We investigated how these mediators affect the phenotypes of colonic mucosa nerve fibers, neuron differentiation, and fiber outgrowth. METHODS We analyzed mucosal biopsy samples collected from 101 patients with IBS and 23 asymptomatic healthy individuals (controls). We measured levels of neuronal-specific enolase, growth-associated protein 43, nerve growth factor (NGF), and tyrosine kinase receptor A (NTRK1) by immunohistochemistry and enzyme-linked immunosorbent assay. Primary rat enteric neurons and human SH-SY5Y cells were incubated with supernatants from the mucosal biopsies and analyzed by morphometric and polymerase chain reaction analyses. RESULTS Compared with mucosal tissues of controls, mucosa from patients with IBS had a significant increase in the area of lamina propria occupied by neuronal-specific enolase-positive (57.7% increase) and growth-associated protein 43-positive fibers (56.1% increase) and staining density of NGF (89.3% increase) (P < .05 for all). Levels of NGF protein were also increased in tissues from patients with IBS vs controls (18% increase; P = .16) along with levels of NTRK1 (64% increase; P < .05). Mucosal supernatants from tissues of patients with IBS induced higher levels of neuritogenesis in primary culture of enteric neurons, compared with controls, and more NGF-dependent neuronal sprouting in SH-SY5Y cells. CONCLUSIONS Nerve fiber density and sprouting, as well as expression of NGF and NTRK1, are significantly increased in mucosal tissues of patients with IBS. Mucosal mediators participate to these neuroplastic changes.
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Affiliation(s)
- Giovanni Dothel
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Maria Raffaella Barbaro
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Hélène Boudin
- Inserm, U913, Institut des Maladies de l'Appareil Digestif du CHU de Nantes; University of Nantes, Nantes, France
| | - Valentina Vasina
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Cesare Cremon
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Luciana Gargano
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Lara Bellacosa
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Roberto De Giorgio
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Catherine Le Berre-Scoul
- Inserm, U913, Institut des Maladies de l'Appareil Digestif du CHU de Nantes; University of Nantes, Nantes, France
| | - Philippe Aubert
- Inserm, U913, Institut des Maladies de l'Appareil Digestif du CHU de Nantes; University of Nantes, Nantes, France
| | - Michel Neunlist
- Inserm, U913, Institut des Maladies de l'Appareil Digestif du CHU de Nantes; University of Nantes, Nantes, France
| | - Fabrizio De Ponti
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Vincenzo Stanghellini
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy
| | - Giovanni Barbara
- Department of Medical and Surgical Sciences and Center for Applied Biomedical Research (CRBA), University of Bologna, Italy.
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164
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Yang B, Zhou X, Lan C. Changes of cytokine levels in a mouse model of post-infectious irritable bowel syndrome. BMC Gastroenterol 2015; 15:43. [PMID: 25886744 PMCID: PMC4426540 DOI: 10.1186/s12876-015-0272-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 03/20/2015] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a highly prevalent functional gastrointestinal disorder. Post-infectious IBS (PI-IBS) is caused by an acute gastrointestinal infection preceding the onset of symptoms. However, the pathophysiology of PI-IBS is not clear, and the purpose of this study was to investigate the probable immune mechanisms of PI-IBS. METHODS C57BL/6 mice were randomly assigned to either an infection group or a control group. Mice in the infection group were infected with Trichinella spiralis to establish a model of PI-IBS (500 Trichinella), while control mice received only salt solution. Visceral sensitivity of colorectal distention in mice was evaluated by abdominal withdrawal reflex scores and intestinal inflammation was assessed using hematoxylin-eosin staining; at day 56 post-infection, the mRNA and protein levels of specific cytokines in the gut segments were detected using reverse-transcription polymerase chain reaction and enzyme-linked immunoabsorbent assay. RESULTS Levels of interferon γ and interleukin (IL)-17 in the PI-IBS group were significantly increased in the duodenum and ileum, and IL-10 was decreased in the jejunum, ileum, and colon compared with control mice. However, the expression level of IL-1β was not significantly different between the two groups. CONCLUSIONS The present study suggests that the local low-grade inflammation and immune activation that are an important component of the pathophysiology of PI-IBS are primarily induced and maintained by specific cytokines.
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Affiliation(s)
- Bo Yang
- Department of Gastroenterology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 4000 l6, China.
| | - Xuchun Zhou
- Department of Gastroenterology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 4000 l6, China.
| | - Cheng Lan
- Department of Gastroenterology, Hainan Provincial People's Hospital, Haikou, 570311, China.
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165
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Soluble mediators in plasma from irritable bowel syndrome patients excite rat submucosal neurons. Brain Behav Immun 2015; 44:57-67. [PMID: 25150006 DOI: 10.1016/j.bbi.2014.08.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/05/2014] [Accepted: 08/12/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Episodic bouts of abdominal pain and altered bowel habit are characteristic of irritable bowel syndrome (IBS). Although a comprehensive understanding of IBS pathophysiology remains elusive, support is growing for a primary role for immune activation in disease severity as evidenced by altered cytokine profiles in IBS plasma. Additionally, aberrant stimulation of the stress axis is likely to result in altered plasma constituents. METHODS Whole-mount preparations of submucosal plexus from adult male Sprague Dawley rats were exposed to plasma from IBS patients and healthy controls. Ratiometric calcium imaging recordings were used to measure changes in intracellular calcium ([Ca(2+)]i) as a marker of neuronal excitability. KEY RESULTS IBS plasma stimulated a robust increase in [Ca(2+)]i (0.09 ± 0.02) whereas plasma from healthy volunteers had little effect (-0.02 ± 0.02, n=24, p<0.001). The neuromodulatory actions of IBS plasma were reduced by pre-neutralisation with anti-interleukin (IL)-6 (p<0.01) but not IL-8, immunoglobulin G or C-reactive protein. Moreover, IBS plasma-evoked responses (0.22 ± 0.06) were inhibited by the corticotrophin releasing factor receptor (CRFR) 1 antagonist, antalarmin (1μM, 0.015 ± 0.02, n=14, p<0.05), but not the CRFR2 antagonist, astressin 2B. Neuronal activation was mediated by ERK/MAPK signalling. CONCLUSIONS These data provide evidence that factors present in IBS plasma modulate neuronal activity in the submucosal plexus and that this is likely to involve CRFR1 activation and IL-6 signalling. These neuromodulatory actions of stress and immune factors indicate a potential mechanism by which immune activation during periods of stress may lead to symptom flares in IBS.
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166
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Rajilić-Stojanović M, Jonkers DM, Salonen A, Hanevik K, Raes J, Jalanka J, de Vos WM, Manichanh C, Golic N, Enck P, Philippou E, Iraqi FA, Clarke G, Spiller RC, Penders J. Intestinal microbiota and diet in IBS: causes, consequences, or epiphenomena? Am J Gastroenterol 2015; 110:278-87. [PMID: 25623659 PMCID: PMC4317767 DOI: 10.1038/ajg.2014.427] [Citation(s) in RCA: 259] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 12/08/2014] [Accepted: 12/09/2014] [Indexed: 12/11/2022]
Abstract
Irritable bowel syndrome (IBS) is a heterogeneous functional disorder with a multifactorial etiology that involves the interplay of both host and environmental factors. Among environmental factors relevant for IBS etiology, the diet stands out given that the majority of IBS patients report their symptoms to be triggered by meals or specific foods. The diet provides substrates for microbial fermentation, and, as the composition of the intestinal microbiota is disturbed in IBS patients, the link between diet, microbiota composition, and microbial fermentation products might have an essential role in IBS etiology. In this review, we summarize current evidence regarding the impact of diet and the intestinal microbiota on IBS symptoms, as well as the reported interactions between diet and the microbiota composition. On the basis of the existing data, we suggest pathways (mechanisms) by which diet components, via the microbial fermentation, could trigger IBS symptoms. Finally, this review provides recommendations for future studies that would enable elucidation of the role of diet and microbiota and how these factors may be (inter)related in the pathophysiology of IBS.
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Affiliation(s)
- Mirjana Rajilić-Stojanović
- Department of Biochemical Engineering and Biotechnology, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | - Daisy M Jonkers
- Division Gastroenterology-Hepatology, School for Nutrition, Toxicology and Metabolism (NUTRIM), Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Anne Salonen
- Immunobiology Research Programme, Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - Kurt Hanevik
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Jeroen Raes
- Department Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Jonna Jalanka
- Department of Veterinary Biosciences, Microbiology, University of Helsinki, Helsinki, Finland
| | - Willem M de Vos
- Immunobiology Research Programme, Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
- Department of Veterinary Biosciences, Microbiology, University of Helsinki, Helsinki, Finland
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Chaysavanh Manichanh
- Digestive System Research Unit, University Hospital Vall d'Hebron, Ciberehd, Barcelona, Spain
| | - Natasa Golic
- Laboratory for Molecular Microbiology, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia
| | - Paul Enck
- Department of Psychosomatic Medicine and Psychotherapy, University Hospital Tuebingen, Tìbingen, Germany
| | - Elena Philippou
- Department of Life and Health Sciences, School of Sciences and Engineering, University of Nicosia, Nicosia, Cyprus
| | - Fuad A Iraqi
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Gerard Clarke
- Department of Psychiatry and Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Robin C Spiller
- Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Queens Medical Centre, Nottingham, UK
| | - John Penders
- Department of Medical Microbiology, School for Nutrition, Toxicology and Metabolism (NUTRIM), Maastricht University Medical Center+, Maastricht, The Netherlands
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167
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Effect of prolonged stress on the adrenal hormones of individuals with irritable bowel syndrome. Biopsychosoc Med 2015; 9:4. [PMID: 25632298 PMCID: PMC4308893 DOI: 10.1186/s13030-015-0031-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/12/2015] [Indexed: 01/30/2023] Open
Abstract
Background The purpose of this study was to investigate the effect of prolonged stress on the salivary adrenal hormones (cortisol, dehydroepiandrosterone [DHEA], DHEA-sulfate [DHEA-S]) of individuals with irritable bowel syndrome (IBS). Methods The participants were female college students, including 10 with IBS and 16 without IBS (control group), who were scheduled for a 2-week teaching practice at a kindergarten. Participants were asked to collect saliva for determining adrenal hormones immediately and 30 min after awakening and before sleep, 2 weeks before the practice, the first week of the practice, the second week of the practice, and a few days after the practice. Results Regarding cortisol/DHEA ratio, significantly increased levels were found during the first week of the practice, and a significant interaction between group and time was found; the ratio at 30 min after awakening in the IBS group was higher than that in the control group. For the other adrenal hormone indexes, no significant differences due to the presence of IBS were found. Conclusions Individuals with IBS showed an elevated cortisol/DHEA ratio after awakening compared with individuals without IBS, and the elevated ratio peaked under the prolonged stress. The present study suggests that the cortisol effect is dominant in individuals with IBS under prolonged stress.
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168
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Deiteren A, De Man JG, Pelckmans PA, De Winter BY. Histamine H₄ receptors in the gastrointestinal tract. Br J Pharmacol 2015; 172:1165-78. [PMID: 25363289 DOI: 10.1111/bph.12989] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/28/2014] [Accepted: 10/20/2014] [Indexed: 12/13/2022] Open
Abstract
Histamine is a well-established mediator involved in a variety of physiological and pathophysiological mechanisms and exerts its effect through activation of four histamine receptors (H1-H₄). The histamine H₄ receptor is the newest member of this histamine receptor family, and is expressed throughout the gastrointestinal tract as well as in the liver, pancreas and bile ducts. Functional studies using a combination of selective and non-selective H₄ receptor ligands have rapidly increased our knowledge of H₄ receptor involvement in gastrointestinal processes both under physiological conditions and in models of disease. Strong evidence points towards a role for H₄ receptors in the modulation of immune-mediated responses in gut inflammation such as in colitis, ischaemia/reperfusion injury, radiation-induced enteropathy and allergic gut reactions. In addition, data have emerged implicating H₄ receptors in gastrointestinal cancerogenesis, sensory signalling, and visceral pain as well as in gastric ulceration. These studies highlight the potential of H₄ receptor targeted therapy in the treatment of various gastrointestinal disorders such as inflammatory bowel disease, irritable bowel syndrome and cancer.
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Affiliation(s)
- A Deiteren
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology, University of Antwerp, Antwerp, Belgium
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169
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Ostertag D, Buhner S, Michel K, Pehl C, Kurjak M, Götzberger M, Schulte-Frohlinde E, Frieling T, Enck P, Phillip J, Schemann M. Reduced Responses of Submucous Neurons from Irritable Bowel Syndrome Patients to a Cocktail Containing Histamine, Serotonin, TNFα, and Tryptase (IBS-Cocktail). Front Neurosci 2015; 9:465. [PMID: 26733780 PMCID: PMC4679876 DOI: 10.3389/fnins.2015.00465] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 11/23/2015] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND AND AIMS Malfunctions of enteric neurons are believed to play an important role in the pathophysiology of irritable bowel syndrome (IBS). Our aim was to investigate whether neuronal activity in biopsies from IBS patients is altered in comparison to healthy controls (HC). METHODS Activity of human submucous neurons in response to electrical nerve stimulation and local application of nicotine or a mixture of histamine, serotonin, tryptase, and TNF-α (IBS-cocktail) was recorded in biopsies from 17 HC and 35 IBS patients with the calcium-sensitive-dye Fluo-4 AM. The concentrations of the mediators resembeled those found in biopsy supernatants or blood. Neuronal activity in guinea-pig submucous neurons was studied with the voltage-sensitive-dye di-8-ANEPPS. RESULTS Activity in submucous ganglia in response to nicotine or electrical nerve stimulation was not different between HC and IBS patients (P = 0.097 or P = 0.448). However, the neuronal response after application of the IBS-cocktail was significantly decreased (P = 0.039) independent of whether diarrhea (n = 12), constipation (n = 5) or bloating (n = 5) was the predominant symptom. In agreement with this we found that responses of submucous ganglia conditioned by overnight incubation with IBS mucosal biopsy supernatant to spritz application of this supernatant was significantly reduced (P = 0.019) when compared to incubation with HC supernatant. CONCLUSION We demonstrated for the first time reduced neuronal responses in mucosal IBS biopsies to an IBS mediator cocktail. While excitability to classical stimuli of enteric neurons was comparable to HC, the activation by the IBS-cocktail was decreased. This was very likely due to desensitization to mediators constantly released by mucosal and immune cells in the gut wall of IBS patients.
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Affiliation(s)
| | - Sabine Buhner
- Human Biology, Technische Universität MünchenFreising, Germany
| | - Klaus Michel
- Human Biology, Technische Universität MünchenFreising, Germany
| | | | | | | | | | | | - Paul Enck
- Academic Hospital TübingenTübingen, Germany
| | | | - Michael Schemann
- Human Biology, Technische Universität MünchenFreising, Germany
- *Correspondence: Michael Schemann
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170
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Pinn DM, Aroniadis OC, Brandt LJ. Is fecal microbiota transplantation (FMT) an effective treatment for patients with functional gastrointestinal disorders (FGID)? Neurogastroenterol Motil 2015; 27:19-29. [PMID: 25424663 DOI: 10.1111/nmo.12479] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 11/04/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND Despite its high prevalence and significant effect on quality of life, the etiology of functional gastrointestinal disorders (FGID), and specifically irritable bowel syndrome (IBS), has yet to be fully elucidated. While alterations in immunity, motility, and the brain-gut axis have been implicated in disease pathogenesis, the intestinal microbiota are increasingly being shown to play a role and numerous studies have demonstrated significant differences from normal in the intestinal flora of patients with FGID, and between types of FGID. Fecal microbiota transplantation (FMT) is a curative therapy for Clostridium difficile infection (CDI), a disease hallmarked by intestinal dysbiosis, and FMT is now being explored as a means to also restore intestinal homeostasis in FGID. PURPOSE This review aims to investigate the role of intestinal microbiota in the pathogenesis of FGID, the implications of FMT for the treatment of FGID, and the challenges encountered in measuring response to a specific intervention in patients with FGID.
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Affiliation(s)
- D M Pinn
- Beth Israel Medical Center, New York, NY, USA
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171
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Abstract
The aetiology and pathology of IBS, a functional bowel disorder thought to lack an organic cause, is largely unknown. However, studies suggest that various features, such as altered composition of the gut microbiota, together with increased intestinal permeability, a changed balance in the enteroendocrine system and a dysregulated immune system in the gut, most likely have an important role in IBS. Exactly how these entities act together and give rise to symptoms is still unknown, but an altered gut microbiota composition could lead to dysregulation of the intestinal barrier as well as the enteroendocrine and the immune systems, which (through interactions with the nervous system) might generate symptoms. This Review highlights the crosstalk between the gut microbiota, the enteroendocrine system, the immune system and the role of intestinal permeability in patients with IBS.
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172
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Mañé N, Gil V, Martínez-Cutillas M, Clavé P, Gallego D, Jiménez M. Differential functional role of purinergic and nitrergic inhibitory cotransmitters in human colonic relaxation. Acta Physiol (Oxf) 2014; 212:293-305. [PMID: 25327170 DOI: 10.1111/apha.12408] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/23/2014] [Accepted: 10/14/2014] [Indexed: 12/18/2022]
Abstract
AIM ATP and nitric oxide (NO) are released from enteric inhibitory motor neurones and are responsible for colonic smooth muscle relaxation. However, how frequency of neural stimulation affects this cotransmission process and the post-junctional responses has not been systematically characterized in the human colon. METHODS The dynamics of inhibitory cotransmission were studied using different protocols of electrical field stimulation (EFS) to characterize the inhibitory junction potentials (IJP) and the corresponding relaxation in colonic strips obtained from 36 patients. RESULTS Single pulses elicited a fast IJP (IJPf(MAX) = -27.6 ± 1.6 mV), sensitive to the P2Y1 antagonist MRS2500 1 μm, that ran down with frequency increase leaving a residual hyperpolarization at high frequencies (IJPf∞ = -3.7 ± 0.6 mV). Accordingly, low frequencies of EFS caused purinergic transient relaxations that cannot be maintained at high frequencies. Addition of the P2Y1 agonist MRS2365 10 μm during the purinergic rundown did not cause any hyperpolarization. Protein kinase C (PKC), a putative P2Y1 desensitizator, was able to reduce the amplitude of the IJPf when activated, but the rundown was not modified by PKC inhibitors. Frequencies higher than 0.60 ± 0.15 Hz were needed to evoke a sustained nitrergic hyperpolarization that progressively increased reaching IJPs∞ = -13 ± 0.4 mV at high frequencies and leading to a sustained inhibition of spontaneous motility. CONCLUSION Changes in frequency of stimulation possibly mimicking neuronal firing will post-junctionally determine purinergic vs. nitrergic responses underlying different functional roles. NO will be responsible for sustained relaxations needed in physiological processes such as storage, while purinergic neurotransmission evoking sharp transient relaxations will be dominant in processes such as propulsion.
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Affiliation(s)
- N. Mañé
- Department of Cell Biology, Physiology and Immunology and Neuroscience Institute; Universitat Autònoma de Barcelona; Barcelona Spain
| | - V. Gil
- Department of Cell Biology, Physiology and Immunology and Neuroscience Institute; Universitat Autònoma de Barcelona; Barcelona Spain
| | - M. Martínez-Cutillas
- Department of Cell Biology, Physiology and Immunology and Neuroscience Institute; Universitat Autònoma de Barcelona; Barcelona Spain
| | - P. Clavé
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd); Instituto de Salud Carlos III; Barcelona Spain
| | - D. Gallego
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd); Instituto de Salud Carlos III; Barcelona Spain
| | - M. Jiménez
- Department of Cell Biology, Physiology and Immunology and Neuroscience Institute; Universitat Autònoma de Barcelona; Barcelona Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd); Instituto de Salud Carlos III; Barcelona Spain
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Intestinal permeability--a new target for disease prevention and therapy. BMC Gastroenterol 2014; 14:189. [PMID: 25407511 PMCID: PMC4253991 DOI: 10.1186/s12876-014-0189-7] [Citation(s) in RCA: 1087] [Impact Index Per Article: 108.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 10/17/2014] [Indexed: 02/06/2023] Open
Abstract
Data are accumulating that emphasize the important role of the intestinal barrier and intestinal permeability for health and disease. However, these terms are poorly defined, their assessment is a matter of debate, and their clinical significance is not clearly established. In the present review, current knowledge on mucosal barrier and its role in disease prevention and therapy is summarized. First, the relevant terms 'intestinal barrier' and 'intestinal permeability' are defined. Secondly, the key element of the intestinal barrier affecting permeability are described. This barrier represents a huge mucosal surface, where billions of bacteria face the largest immune system of our body. On the one hand, an intact intestinal barrier protects the human organism against invasion of microorganisms and toxins, on the other hand, this barrier must be open to absorb essential fluids and nutrients. Such opposing goals are achieved by a complex anatomical and functional structure the intestinal barrier consists of, the functional status of which is described by 'intestinal permeability'. Third, the regulation of intestinal permeability by diet and bacteria is depicted. In particular, potential barrier disruptors such as hypoperfusion of the gut, infections and toxins, but also selected over-dosed nutrients, drugs, and other lifestyle factors have to be considered. In the fourth part, the means to assess intestinal permeability are presented and critically discussed. The means vary enormously and probably assess different functional components of the barrier. The barrier assessments are further hindered by the natural variability of this functional entity depending on species and genes as well as on diet and other environmental factors. In the final part, we discuss selected diseases associated with increased intestinal permeability such as critically illness, inflammatory bowel diseases, celiac disease, food allergy, irritable bowel syndrome, and--more recently recognized--obesity and metabolic diseases. All these diseases are characterized by inflammation that might be triggered by the translocation of luminal components into the host. In summary, intestinal permeability, which is a feature of intestinal barrier function, is increasingly recognized as being of relevance for health and disease, and therefore, this topic warrants more attention.
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Friedman SL, Quigley EMM, Sharkey KA, Sung JJY, Whitcomb DC. The past 10 years of gastroenterology and hepatology-reflections and predictions. Nat Rev Gastroenterol Hepatol 2014; 11:692-700. [PMID: 25291429 DOI: 10.1038/nrgastro.2014.167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In November 2004, the very first issue of this journal featured articles on the pathogenesis of ulcerative colitis, mechanisms leading to chronic pancreatitis, and treatment of recurrent Clostridium-difficile-associated diarrhoea. Although those topics might seem familiar, much has changed in the intervening years in our understanding, diagnosis and treatment of many different diseases across the field of gastroenterology and hepatology. Nonetheless, many challenges remain. Here, we have asked five of our Advisory Board members-international experts across different subspecialties in gastroenterology and hepatology-to reflect on the progress and frustrations of the past 10 years. They also comment on where effort and money should be invested now, as well as their predictions for progress in the next 10 years.
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Affiliation(s)
- Scott L Friedman
- Division of Liver Disease, Box 1123, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Room 11-70C, New York, NY 10029-6574, USA
| | - Eamonn M M Quigley
- Division of Gastroenterology and Hepatology, Houston Methodist Hospital, 6550 Fannin Street, SM 1001, Houston, TX 77030, USA
| | - Keith A Sharkey
- Hotchkiss Brain Institute and Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Joseph J Y Sung
- University Administration Building, The Chinese University of Hong Kong, 1/F, Room 101, Shatin, NT, Hong Kong SAR, The People's Republic of China
| | - David C Whitcomb
- Department of Medicine, Cell Biology &Molecular Physiology and Human Genetics, University of Pittsburgh and UPMC, Room 401.4, 3708 Fifth Avenue, Pittsburgh, PA 15231, USA
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Vanuytsel T, Vanormelingen C, Vanheel H, Masaoka T, Salim Rasoel S, Tóth J, Houben E, Verbeke K, De Hertogh G, Berghe PV, Tack J, Farré R. From intestinal permeability to dysmotility: the biobreeding rat as a model for functional gastrointestinal disorders. PLoS One 2014; 9:e111132. [PMID: 25354336 PMCID: PMC4212994 DOI: 10.1371/journal.pone.0111132] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 09/19/2014] [Indexed: 12/15/2022] Open
Abstract
Background Impaired intestinal barrier function, low-grade inflammation and altered neuronal control are reported in functional gastrointestinal disorders. However, the sequence of and causal relation between these events is unclear, necessitating a spontaneous animal model. The aim of this study was to describe the natural history of intestinal permeability, mucosal and neuromuscular inflammation and nitrergic motor neuron function during the lifetime of the BioBreeding (BB) rat. Methods Normoglycemic BB-diabetes prone (DP) and control rats were sacrificed at different ages and jejunum was harvested to characterize intestinal permeability, inflammation and neuromuscular function. Results Both structural and functional evidence of increased intestinal permeability was found in young BB-DP rats from the age of 50 days. In older animals, starting in the mucosa from 70 days and in half of the animals also in the muscularis propria from 110 days, an inflammatory reaction, characterized by an influx of polymorphonuclear cells and higher myeloperoxidase activity, was observed. Finally, in animals older than 110 days, coinciding with a myenteric ganglionitis, a loss of nitrergic neurons and motor function was demonstrated. Conclusion In the BB-rat, mucosal inflammatory cell infiltration is preceded by intestinal barrier dysfunction and followed by myenteric ganglionitis and loss of nitrergic function. This sequence supports a primary role for impaired barrier function and provides an insightful model for the pathogenesis of functional gastrointestinal disorders.
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Affiliation(s)
- Tim Vanuytsel
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Christophe Vanormelingen
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Hanne Vanheel
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Tatsuhiro Masaoka
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Shadea Salim Rasoel
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Joran Tóth
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Els Houben
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Kristin Verbeke
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Gert De Hertogh
- Department of Pathology, University Hospital, University of Leuven, Leuven, Belgium
| | - Pieter Vanden Berghe
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
- * E-mail:
| | - Ricard Farré
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos II, Barcelona, Spain
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Abstract
The gastrointestinal tract is innervated by several distinct populations of neurons, whose cell bodies either reside within (intrinsic) or outside (extrinsic) the gastrointestinal wall. Normally, most individuals are unaware of the continuous, complicated functions of these neurons. However, for patients with gastrointestinal disorders, such as IBD and IBS, altered gastrointestinal motility, discomfort and pain are common, debilitating symptoms. Although bouts of intestinal inflammation underlie the symptoms associated with IBD, increasing preclinical and clinical evidence indicates that infection and inflammation are also key risk factors for the development of other gastrointestinal disorders. Notably, a strong correlation exists between prior exposure to gut infection and symptom occurrence in IBS. This Review discusses the evidence for neuroplasticity (structural, synaptic or intrinsic changes that alter neuronal function) affecting gastrointestinal function. Such changes are evident during inflammation and, in many cases, long after healing of the damaged tissues, when the nervous system fails to reset back to normal. Neuroplasticity within distinct populations of neurons has a fundamental role in the aberrant motility, secretion and sensation associated with common clinical gastrointestinal disorders. To find appropriate therapeutic treatments for these disorders, the extent and time course of neuroplasticity must be fully appreciated.
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177
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Buckley MM, O'Halloran KD, Rae MG, Dinan TG, O'Malley D. Modulation of enteric neurons by interleukin-6 and corticotropin-releasing factor contributes to visceral hypersensitivity and altered colonic motility in a rat model of irritable bowel syndrome. J Physiol 2014; 592:5235-50. [PMID: 25260633 DOI: 10.1113/jphysiol.2014.279968] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The search for effective therapeutic strategies for irritable bowel syndrome (IBS) is hampered by an incomplete understanding of its underlying pathophysiology. Stress and altered plasma cytokine profiles indicative of immune activation are characteristic of the disorder. The neuromodulatory effects of interleukin-6 (IL-6) and corticotropin-releasing factor receptor (CRFR) 1 in visceral pain and stress-induced defecation in the Wistar Kyoto (WKY) rat model of IBS were investigated. Sprague Dawley and WKY rats were administered anti-IL-6 receptor antibodies (xIL-6R, 0.5 mg kg(-1) i.p) with or without the CRFR1 antagonist antalarmin (10 mg kg(-1) i.p). Post-intervention, the pain threshold to colorectal distension and stress-induced faecal output were compared and changes in colonic mucosal protein expression were investigated. The neuro-stimulatory effects of IBS plasma on the myenteric plexus is mediated by IL-6, IL-8 and CRF. The stimulatory effects of these soluble factors on myenteric neuron excitability and colonic contractility were additive. Moreover, inhibition of IL-6 and CRF1 receptors in vivo in the WKY IBS rat model normalized stress-induced defecation (P < 0.01) and visceral pain sensitivity (P < 0.001) with associated changes in protein expression of the tight junction proteins occludin and claudin 2, the visceral pain-associated T-type calcium channel CaV3.2 and intracellular signalling molecules STAT3, SOCS3 and ERK1/2. These studies demonstrate the additive effects of immune and stress factors on myenteric neuronal excitability. Moreover, combined targeting of peripheral IL-6 and CRF1 receptors is effective in alleviating IBS-like symptoms in the WKY rat. Thus, crosstalk between stress and immune factors during IBS flares may underlie symptom exacerbation.
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Affiliation(s)
- Maria M Buckley
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Physiology, University College Cork, Cork, Ireland
| | - Ken D O'Halloran
- Department of Physiology, University College Cork, Cork, Ireland
| | - Mark G Rae
- Department of Physiology, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Psychiatry, University College Cork, Cork, Ireland
| | - Dervla O'Malley
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Physiology, University College Cork, Cork, Ireland
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178
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Buckley MM, O'Halloran KD, Rae MG, Dinan TG, O'Malley D. Modulation of enteric neurons by interleukin-6 and corticotropin-releasing factor contributes to visceral hypersensitivity and altered colonic motility in a rat model of irritable bowel syndrome. J Physiol 2014. [PMID: 25260633 DOI: 10.1113/jphysiol] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The search for effective therapeutic strategies for irritable bowel syndrome (IBS) is hampered by an incomplete understanding of its underlying pathophysiology. Stress and altered plasma cytokine profiles indicative of immune activation are characteristic of the disorder. The neuromodulatory effects of interleukin-6 (IL-6) and corticotropin-releasing factor receptor (CRFR) 1 in visceral pain and stress-induced defecation in the Wistar Kyoto (WKY) rat model of IBS were investigated. Sprague Dawley and WKY rats were administered anti-IL-6 receptor antibodies (xIL-6R, 0.5 mg kg(-1) i.p) with or without the CRFR1 antagonist antalarmin (10 mg kg(-1) i.p). Post-intervention, the pain threshold to colorectal distension and stress-induced faecal output were compared and changes in colonic mucosal protein expression were investigated. The neuro-stimulatory effects of IBS plasma on the myenteric plexus is mediated by IL-6, IL-8 and CRF. The stimulatory effects of these soluble factors on myenteric neuron excitability and colonic contractility were additive. Moreover, inhibition of IL-6 and CRF1 receptors in vivo in the WKY IBS rat model normalized stress-induced defecation (P < 0.01) and visceral pain sensitivity (P < 0.001) with associated changes in protein expression of the tight junction proteins occludin and claudin 2, the visceral pain-associated T-type calcium channel CaV3.2 and intracellular signalling molecules STAT3, SOCS3 and ERK1/2. These studies demonstrate the additive effects of immune and stress factors on myenteric neuronal excitability. Moreover, combined targeting of peripheral IL-6 and CRF1 receptors is effective in alleviating IBS-like symptoms in the WKY rat. Thus, crosstalk between stress and immune factors during IBS flares may underlie symptom exacerbation.
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Affiliation(s)
- Maria M Buckley
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Physiology, University College Cork, Cork, Ireland
| | - Ken D O'Halloran
- Department of Physiology, University College Cork, Cork, Ireland
| | - Mark G Rae
- Department of Physiology, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Psychiatry, University College Cork, Cork, Ireland
| | - Dervla O'Malley
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland Department of Physiology, University College Cork, Cork, Ireland
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179
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Intraepithelial lymphocyte eotaxin-2 expression and perineural mast cell degranulation differentiate allergic/eosinophilic colitis from classic IBD. J Pediatr Gastroenterol Nutr 2014; 59:300-7. [PMID: 24813533 DOI: 10.1097/mpg.0000000000000432] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVES Allergic colitis shows overlap with classic inflammatory bowel disease (IBD). Clinically, allergic colitis is associated with dysmotility and abdominal pain, and mucosal eosinophilia is characteristic. We thus aimed to characterise mucosal changes in children with allergic colitis compared with normal tissue and classic IBD, focusing on potential interaction between eosinophils and mast cells with enteric neurones. METHODS A total of 15 children with allergic colitis, 10 with Crohn disease (CD), 10 with ulcerative colitis (UC), and 10 histologically normal controls were studied. Mucosal biopsies were stained for CD3 T cells, Ki-67, eotaxin-1, and eotaxin-2. Eotaxin-2, IgE, and tryptase were localised compared with mucosal nerves, using neuronal markers neurofilament protein, neuron-specific enolase, and nerve growth factor receptor. RESULTS Overall inflammation was greater in patients with CD and UC than in patients with allergic colitis. CD3 T-cell density was increased in patients with allergic colitis, similar to that in patients with CD but lower than in patients with UC, whereas eosinophil density was higher than in all other groups. Eotaxin-1 and -2 were localised to basolateral crypt epithelium in all specimens, with eotaxin-1+ lamina propria cells found in all of the colitis groups. Eotaxin-2+ intraepithelial lymphocyte (IEL) density was significantly higher in allergic colitis specimens than in all other groups. Mast cell degranulation was strikingly increased in patients with allergic colitis (12/15) compared with that in patients with UC (1/10) and CD (0/1). Tryptase and IgE colocalised on enteric neurons in patients with allergic colitis but rarely in patients with IBD. CONCLUSIONS Eotaxin-2+ IELs may contribute to the periepithelial eosinophil accumulation characteristic of allergic colitis. The colocalisation of IgE and tryptase with mucosal enteric nerves is likely to promote the dysmotility and visceral hyperalgesia classically seen in allergic gastrointestinal inflammation.
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180
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Abstract
The past decade has witnessed an explosion of knowledge regarding the vast microbial community that resides within our intestine-the gut microbiota. The topic has generated great expectations in terms of gaining a better understanding of disorders ranging from IBD to metabolic disorders and obesity. IBS is a condition for which investigators have long been in search of plausible underlying pathogeneses and it is inevitable that altered composition or function of the gut microbiota will be considered as a potential aetiological factor in at least a subset of patients with IBS. This Review describes the evidence implicating the gut microbiota in not only the expression of the intestinal manifestations of IBS, but also the psychiatric morbidity that coexists in up to 80% of patients with IBS. The evidence described herein ranges from proof-of-concept studies in animals to observational studies and clinical trials in humans. The gut microbiota is subject to influences from a diverse range of factors including diet, antibiotic usage, infection and stress. These factors have previously been implicated in the pathophysiology of IBS and further prompt consideration of a role for the gut microbiota in IBS.
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181
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Buhner S, Braak B, Li Q, Kugler EM, Klooker T, Wouters M, Donovan J, Vignali S, Mazzuoli-Weber G, Grundy D, Boeckxstaens G, Schemann M. Neuronal activation by mucosal biopsy supernatants from irritable bowel syndrome patients is linked to visceral sensitivity. Exp Physiol 2014; 99:1299-311. [DOI: 10.1113/expphysiol.2014.080036] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Sabine Buhner
- Human Biology; Technische Universität München; Freising Germany
| | - Breg Braak
- Department of Gastroenterology and Hepatology; Academic Medical Center; Amsterdam The Netherlands
| | - Qin Li
- Human Biology; Technische Universität München; Freising Germany
- Department of Physiology; Shangdong University; Shangdong China
| | | | - Tamira Klooker
- Department of Gastroenterology and Hepatology; Academic Medical Center; Amsterdam The Netherlands
| | - Mira Wouters
- Translational Research Center for Gastrointestinal Disorders; University Hospital Gasthuisberg; Catholic University of Leuven; Leuven Belgium
| | - Jemma Donovan
- Department of Biomedical Science; University of Sheffield; Sheffield UK
| | - Sheila Vignali
- Human Biology; Technische Universität München; Freising Germany
| | | | - David Grundy
- Department of Biomedical Science; University of Sheffield; Sheffield UK
| | - Guy Boeckxstaens
- Department of Gastroenterology and Hepatology; Academic Medical Center; Amsterdam The Netherlands
- Translational Research Center for Gastrointestinal Disorders; University Hospital Gasthuisberg; Catholic University of Leuven; Leuven Belgium
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182
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Taverniti V, Guglielmetti S. Methodological issues in the study of intestinal microbiota in irritable bowel syndrome. World J Gastroenterol 2014; 20:8821-8836. [PMID: 25083056 PMCID: PMC4112874 DOI: 10.3748/wjg.v20.i27.8821] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 04/10/2014] [Accepted: 06/05/2014] [Indexed: 02/06/2023] Open
Abstract
Irritable bowel syndrome (IBS) is an intestinal functional disorder with the highest prevalence in the industrialized world. The intestinal microbiota (IM) plays a role in the pathogenesis of IBS and is not merely a consequence of this disorder. Previous research efforts have not revealed unequivocal microbiological signatures of IBS, and the experimental results are contradictory. The experimental methodologies adopted to investigate the complex intestinal ecosystem drastically impact the quality and significance of the results. Therefore, to consider the methodological aspects of the research on IM in IBS, we reviewed 29 relevant original research articles identified through a PubMed search using three combinations of keywords: “irritable bowel syndrome + microflora”, “irritable bowel syndrome + microbiota” and “irritable bowel syndrome + microbiome”. For each study, we reviewed the quality and significance of the scientific evidence obtained with respect to the experimental method adopted. The data obtained from each study were compared with all considered publications to identify potential inconsistencies and explain contradictory results. The analytical revision of the studies referenced in the present review has contributed to the identification of microbial groups whose relative abundance significantly alters IBS, suggesting that these microbial groups could be IM signatures for this syndrome. The identification of microbial biomarkers in the IM can be advantageous for the development of new diagnostic tools and novel therapeutic strategies for the treatment of different subtypes of IBS.
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183
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Abstract
Inflammatory and neuroinflammatory processes are increasingly recognized as critical pathophysiologic steps in the development of multiple chronic diseases and in the etiology of persistent pain and depression. Mast cells are immune cells now viewed as cellular sensors in inflammation and immunity. When stimulated, mast cells release an array of mediators to orchestrate an inflammatory response. These mediators can directly initiate tissue responses on resident cells, and may also regulate the activity of other immune cells, including central microglia. New evidence supports the involvement of peripheral and central mast cells in the development of pain processes as well as in the transition from acute, to chronic and neuropathic pain. That behavioral and endocrine states can increase the number and activation of peripheral and brain mast cells suggests that mast cells represent the immune cells that peripherally and centrally coordinate inflammatory processes in neuropsychiatric diseases such as depression and anxiety which are associated with chronic pelvic pain. Given that increasing evidence supports the activated mast cell as a director of common inflammatory pathways/mechanisms contributing to chronic and neuropathic pelvic pain and comorbid neuropsychiatric diseases, mast cells may be considered a viable target for the multifactorial management of both pain and depression.
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184
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Muscatello MRA, Bruno A, Scimeca G, Pandolfo G, Zoccali RA. Role of negative affects in pathophysiology and clinical expression of irritable bowel syndrome. World J Gastroenterol 2014; 20:7570-7586. [PMID: 24976697 PMCID: PMC4069288 DOI: 10.3748/wjg.v20.i24.7570] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 01/18/2014] [Accepted: 04/03/2014] [Indexed: 02/06/2023] Open
Abstract
Irritable bowel syndrome (IBS) is regarded as a multifactorial disease in which alterations in the brain-gut axis signaling play a major role. The biopsychosocial model applied to the understanding of IBS pathophysiology assumes that psychosocial factors, interacting with peripheral/central neuroendocrine and immune changes, may induce symptoms of IBS, modulate symptom severity, influence illness experience and quality of life, and affect outcome. The present review focuses on the role of negative affects, including depression, anxiety, and anger, on pathogenesis and clinical expression of IBS. The potential role of the autonomic nervous system, stress-hormone system, and immune system in the pathophysiology of both negative affects and IBS are taken into account. Psychiatric comorbidity and subclinical variations in levels of depression, anxiety, and anger are further discussed in relation to the main pathophysiological and symptomatic correlates of IBS, such as sensorimotor functions, gut microbiota, inflammation/immunity, and symptom reporting.
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185
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Kanazawa M, Palsson OS, van Tilburg MA, Gangarosa LM, Fukudo S, Whitehead. WE. Motility response to colonic distention is increased in postinfectious irritable bowel syndrome (PI-IBS). Neurogastroenterol Motil 2014; 26:696-704. [PMID: 24602083 PMCID: PMC4739722 DOI: 10.1111/nmo.12318] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 01/19/2014] [Indexed: 12/21/2022]
Abstract
BACKGROUND Acute intestinal infection leads to persistent intestinal smooth muscle hypercontractility and pain hypersensitivity after resolution of the infection in animal models. We investigated whether postinfectious irritable bowel syndrome (PI-IBS) is associated with abnormalities in phasic contractions of the colon, smooth muscle tone, and pain sensitivity compared to non-PI-IBS (NI-IBS) or healthy controls (HC). METHODS Two hundred and eighteen Rome III-positive IBS patients and 43 HC participated. IBS patients were designated PI-IBS, if their IBS symptoms began following an episode of gastroenteritis characterized by two or more of: fever, vomiting, or diarrhea. Pain threshold to phasic distentions of the descending colon was assessed using a barostat. Colonic motility was assessed with the barostat bag minimally inflated to the individual operating pressure (IOP), at 20 mmHg above the IOP, and following a test meal. IBS symptom severity and psychological symptoms were assessed by the IBS Severity Scale (IBS-SS) and the Brief Symptom Inventory-18 (BSI-18). KEY RESULTS Twenty two (10.1%) met criteria for PI-IBS. Both IBS and HC groups showed a significant increase in motility index during intraluminal distention and following meals. The magnitude of the response to distention above (orad to) the balloon was significantly greater in PI-IBS compared with NI-IBS (p < 0.05) or HC (p < 0.01). Differences between PI-IBS and NI-IBS were not significant for IBS symptom severity, pain threshold, barostat bag volumes, or any psychological score on the BSI-18. CONCLUSIONS & INFERENCES Patients with PI-IBS have greater colonic hypercontractility than NI-IBS. We speculate that sustained mild mucosal inflammation may cause this colonic irritability.
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Affiliation(s)
- Motoyori Kanazawa
- Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, Campus Box 7555, Chapel Hill, NC 27599-7555, USA,Department of Behavioral Medicine, Tohoku University Graduate School of Medicine, 2-1 Seiryo, Aoba, Sendai 980-8575, Japan
| | - Olafur S. Palsson
- Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, Campus Box 7555, Chapel Hill, NC 27599-7555, USA
| | - Miranda A.L. van Tilburg
- Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, Campus Box 7555, Chapel Hill, NC 27599-7555, USA
| | - Lisa M. Gangarosa
- Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, Campus Box 7555, Chapel Hill, NC 27599-7555, USA
| | - Shin Fukudo
- Department of Behavioral Medicine, Tohoku University Graduate School of Medicine, 2-1 Seiryo, Aoba, Sendai 980-8575, Japan
| | - William E. Whitehead.
- Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, Campus Box 7555, Chapel Hill, NC 27599-7555, USA
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Theodorou V, Belgnaoui AA, Agostini S, Eutamene H. Effect of commensals and probiotics on visceral sensitivity and pain in irritable bowel syndrome. Gut Microbes 2014; 5:430-6. [PMID: 25184834 PMCID: PMC4153783 DOI: 10.4161/gmic.29796] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The last ten years' wide progress in the gut microbiota phylogenetic and functional characterization has been made evidencing dysbiosis in several gastrointestinal diseases including inflammatory bowel diseases and irritable bowel syndrome (IBS). IBS is a functional gut disease with high prevalence and negative impact on patient's quality of life characterized mainly by visceral pain and/or discomfort, representing a good paradigm of chronic gut hypersensitivity. The IBS features are strongly regulated by bidirectional gut-brain interactions and there is increasing evidence for the involvement of gut bacteria and/or their metabolites in these features, including visceral pain. Further, gut microbiota modulation by antibiotics or probiotics has been promising in IBS. Mechanistic data provided mainly by animal studies highlight that commensals or probiotics may exert a direct action through bacterial metabolites on sensitive nerve endings in the gut mucosa, or indirect pathways targeting the intestinal epithelial barrier, the mucosal and/or systemic immune activation, and subsequent neuronal sensitization and/or activation.
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Affiliation(s)
- Vassilia Theodorou
- INRA; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,El-Purpan; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,Correspondence to: Vassilia Theodorou,
| | - Afifa Ait Belgnaoui
- INRA; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,El-Purpan; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,Lallemand Health Solutions Inc; Montreal, Canada
| | - Simona Agostini
- INRA; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,El-Purpan; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France
| | - Helene Eutamene
- INRA; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France,El-Purpan; UMR 1331 TOXALIM; Neuro-Gastroenterology and Nutrition Group; Toulouse, France
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187
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Tooth D, Garsed K, Singh G, Marciani L, Lam C, Fordham I, Fields A, Banwait R, Lingaya M, Layfield R, Hastings M, Whorwell P, Spiller R. Characterisation of faecal protease activity in irritable bowel syndrome with diarrhoea: origin and effect of gut transit. Gut 2014; 63:753-60. [PMID: 23911555 PMCID: PMC3995279 DOI: 10.1136/gutjnl-2012-304042] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Faecal serine proteases (FSPs) may play a role in irritable bowel syndrome with diarrhoea (IBS-D), but their origin is unclear. We aimed to structurally characterise them and define the impact of colonic cleansing and transit time. DESIGN Faecal samples were obtained from 30 healthy volunteers (HV) and 79 patients with IBS-D participating in a trial of ondansetron versus placebo. Colonic transit was measured using radio-opaque markers. Samples were also obtained from 24 HV before and after colonic cleansing with the osmotic laxative MoviPrep. FSPs were purified from faecal extracts using benzamidine-Sepharose affinity chromatography. SDS-PAGE profiled components were identified using trypsinolysis and tandem mass spectrometry. Functional protease activity in faecal extracts was measured using a colorimetric assay based on the proteolysis of azo-casein. RESULTS Protein analysis identified the most abundant FSPs as being of human origin and probably derived from pancreatic juice. Functional assays showed increased faecal protease (FP) and amylase in patients with IBS-D compared with HV. Those with higher amylase had significantly higher FP and greater anxiety. FP activity correlated negatively with whole gut transit in patients with IBS-D (Spearman r=-0.32, p=0.005) and HV (r=-0.55, p=0.014). Colon cleansing caused a significant rise in FP activity in HV from a baseline of median (IQR) 253 (140-426) to 1031 (435-2296), levels similar to those seen in patients with IBS-D. FSP activity correlated positively with days/week with urgency. CONCLUSIONS The most abundant FSPs are of human origin. Rapid transit through the colon and/or decreased (possibly bacterial) proteolytic degradation increases their faecal concentration and could contribute to visceral hypersensitivity in patients with IBS-D. CLINICALTRIALSGOV NCT00745004.
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Affiliation(s)
- David Tooth
- School of Biomedical Sciences, University of Nottingham, , Nottingham, Nottinghamshire, UK
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188
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Nasser Y, Boeckxstaens GE, Wouters MM, Schemann M, Vanner S. Using human intestinal biopsies to study the pathogenesis of irritable bowel syndrome. Neurogastroenterol Motil 2014; 26:455-69. [PMID: 24602069 DOI: 10.1111/nmo.12316] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 01/15/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Although animal models of the irritable bowel syndrome (IBS) have provided important insights, there are no models that fully express the features of this complex condition. One alternative approach is the use of human intestinal biopsies obtained during endoscopic procedures to examine peripheral mechanisms in this disorder. These studies have served to confirm the existence of peripheral pathways in humans with IBS and have provided many new mechanistic insights. Two general approaches have been employed; one approach has been to examine the biological activity of mediators within the mucosal tissue of IBS patients and the other has been to examine changes in the structural properties of key signaling pathways contained within the biopsies. Using these approaches, important changes have been discovered involving the enteric nervous system and the extrinsic sensory pathway (dorsal root ganglia neurons), the immune system, and epithelial signaling in IBS patients compared to healthy subjects. PURPOSE This review will systematically explore these mechanistic pathways, highlight the implications of these novel findings and discuss some of the important limitations of this approach.
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Affiliation(s)
- Y Nasser
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, ON, Canada
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189
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Sharkey KA, Savidge TC. Reprint of: Role of enteric neurotransmission in host defense and protection of the gastrointestinal tract. Auton Neurosci 2014; 182:70-82. [PMID: 24674836 DOI: 10.1016/j.autneu.2014.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 12/11/2013] [Indexed: 12/11/2022]
Abstract
Host defense is a vital role played by the gastrointestinal tract. As host to an enormous and diverse microbiome, the gut has evolved an elaborate array of chemical and physicals barriers that allow the digestion and absorption of nutrients without compromising the mammalian host. The control of such barrier functions requires the integration of neural, humoral, paracrine and immune signaling, involving redundant and overlapping mechanisms to ensure, under most circumstances, the integrity of the gastrointestinal epithelial barrier. Here we focus on selected recent developments in the autonomic neural control of host defense functions used in the protection of the gut from luminal agents, and discuss how the microbiota may potentially play a role in enteric neurotransmission. Key recent findings include: the important role played by subepithelial enteric glia in modulating intestinal barrier function, identification of stress-induced mechanisms evoking barrier breakdown, neural regulation of epithelial cell proliferation, the role of afferent and efferent vagal pathways in regulating barrier function, direct evidence for bacterial communication to the enteric nervous system, and microbial sources of enteric neurotransmitters. We discuss these new and interesting developments in our understanding of the role of the autonomic nervous system in gastrointestinal host defense.
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Affiliation(s)
- Keith A Sharkey
- Hotchkiss Brain Institute and Snyder Institute for Chronic Diseases, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada.
| | - Tor C Savidge
- Texas Children's Microbiome Center, Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
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190
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Piche T. Tight junctions and IBS--the link between epithelial permeability, low-grade inflammation, and symptom generation? Neurogastroenterol Motil 2014; 26:296-302. [PMID: 24548256 DOI: 10.1111/nmo.12315] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 01/14/2014] [Indexed: 12/18/2022]
Abstract
In this issue of Neurogastroenterology and Motility, Dr Ewa Wilcz-Villega and colleagues report low expression of E-cadherin, a tight junction protein involved in the regulation of paracellular permeability, in the colonic mucosa of patients with the irritable bowel syndrome (IBS) with predominance of diarrhea (IBS-D) or alternating symptoms (IBS-A). These findings constitute an improvement in our knowledge of epithelial barrier disruption associated with IBS. There is mounting evidence to indicate that a compromised epithelial barrier is associated with low-grade immune activation and intestinal dysfunction in at least a proportion of IBS patients. During the last 10 years of research, much interest has focused on the increase in the number of different types of immune cells in the gut mucosa of IBS patients including: mast cells, T lymphocytes, and other local cells such as enteroendocrine cells. The inflammatory mediators released by these cells or other luminal factors could be at the origin of altered epithelial barrier functions and enteric nervous system signaling, which lead to gut hypersensitivity. A current conceptual framework states that clinical symptoms of IBS could be associated with structural and functional abnormalities of the mucosal barrier, highlighting the crucial importance of elucidating the contributory role of epithelial barrier defects in the pathogenesis of IBS. More importantly, disruption of the epithelial barrier could also participate in the generation of persistent abdominal pain and discomfort mimicking IBS in patients with inflammatory bowel diseases considered in remission. This mini review gives a brief summary of clinical and experimental evidence concerning the mechanisms underlying epithelial barrier defects in IBS.
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Affiliation(s)
- T Piche
- Department of Gastroenterology, CHU, Nice, France
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191
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Ikehara O, Hayashi H, Waguri T, Kaji I, Karaki SI, Kuwahara A, Suzuki Y. Luminal trypsin induces enteric nerve-mediated anion secretion in the mouse cecum. J Physiol Sci 2014; 64:119-28. [PMID: 24421180 PMCID: PMC10717537 DOI: 10.1007/s12576-013-0302-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 12/10/2013] [Indexed: 02/08/2023]
Abstract
Proteases play a diverse role in health and disease. An excessive concentration of proteases has been found in the feces of patients with inflammatory bowel disease or irritable bowel syndrome and been implicated in the pathogenesis of such disorders. This study examined the effect of the serine protease, trypsin, on intestinal epithelial anion secretion when added to the luminal side. A mucosal-submucosal sheet of the mouse cecum was mounted in Ussing chambers, and the short-circuit current (I sc) was measured. Trypsin added to the mucosal (luminal) side increased I sc with an ED50 value of approximately 10 μM. This I sc increase was suppressed by removing Cl(-) from the bathing solution. The I sc increase induced by 10-100 μM trypsin was substantially suppressed by tetrodotoxin, and partially inhibited by a neurokinin-1 receptor antagonist, but not by a muscarinic or nicotinic ACh-receptor antagonist. The trypsin-induced I sc increase was also significantly inhibited by a 5-hydroxytryptamine-3 receptor (5-HT3) antagonist and substantially suppressed by the simultaneous addition of both 5-HT3 and 5-HT4 receptor antagonists. We conclude that luminal trypsin activates the enteric reflex to induce anion secretion, 5-HT and substance P playing important mediating roles in this secreto-motor reflex. Luminal proteases may contribute to the cause of diarrhea occurring with some intestinal disorders.
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Affiliation(s)
- Osamu Ikehara
- Laboratory of Physiology, Department of Food and Nutritional Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Hisayoshi Hayashi
- Laboratory of Physiology, Department of Food and Nutritional Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Toshiharu Waguri
- Laboratory of Physiology, Department of Food and Nutritional Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Izumi Kaji
- Laboratory of Physiology, Department of Environmental Health Sciences, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Shin-ichiro Karaki
- Laboratory of Physiology, Department of Environmental Health Sciences, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Atsukazu Kuwahara
- Laboratory of Physiology, Department of Environmental Health Sciences, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
| | - Yuichi Suzuki
- Laboratory of Physiology, Department of Food and Nutritional Sciences, University of Shizuoka, Yada 52-1, Surugaku, Shizuoka, 422-8526 Japan
- Laboratory of Anatomy and Physiology, Department of Health and Nutrition, Sendai Shirayuri Women’s College, Hondacho 6-1, Izumi-ku, Sendai, 981-3107 Japan
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192
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Smolinska S, Jutel M, Crameri R, O'Mahony L. Histamine and gut mucosal immune regulation. Allergy 2014; 69:273-81. [PMID: 24286351 DOI: 10.1111/all.12330] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2013] [Indexed: 11/28/2022]
Abstract
Histamine is a biogenic amine with extensive effects on many cell types, mediated by the activation of its four receptors (H1R-H4R). Distinct effects are dependent on receptor subtypes and their differential expression. Within the gastrointestinal tract, histamine is present at relatively high concentrations, particularly during inflammatory responses. In this review, we discuss the immunoregulatory influence of histamine on a number of gastrointestinal disorders, including food allergy, scombroid food poisoning, histamine intolerance, irritable bowel syndrome, and inflammatory bowel disease. It is clear that the effects of histamine on mucosal immune homeostasis are dependent on expression and activity of the four currently known histamine receptors; however, the relative protective or pathogenic effects of histamine on inflammatory processes within the gut are still poorly defined and require further investigation.
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Affiliation(s)
- S. Smolinska
- Department of Clinical Immunology; Wroclaw Medical University; Wroclaw Poland
- ‘ALL-MED’ Medical Research Institute; Wroclaw Poland
| | - M. Jutel
- Department of Clinical Immunology; Wroclaw Medical University; Wroclaw Poland
- ‘ALL-MED’ Medical Research Institute; Wroclaw Poland
| | - R. Crameri
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos Switzerland
| | - L. O'Mahony
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos Switzerland
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193
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Martins PR, Nascimento RD, de Souza Lisboa A, Martinelli PM, d'Ávila Reis D. Neuroimmunopathology of Trypanosoma cruzi-induced megaoesophagus: Is there a role for mast cell proteases? Hum Immunol 2014; 75:302-5. [PMID: 24530752 DOI: 10.1016/j.humimm.2014.02.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 01/03/2014] [Accepted: 02/04/2014] [Indexed: 01/18/2023]
Abstract
Tryptase and chymase are mast cell (MC)-specific proteases, which influence in the activation of inflammatory cells. In this study, we quantified tryptase- or chymase-expressing MCs in the oesophaguses of Chagas patients, and searched for a correlation between those data with area of nerve fibres that expressed either PGP9.5 (pan-marker) or vasoactive intestinal polypeptide (VIP), which is a neuromediator that has anti-inflammatory activity. Samples from the oesophaguses of 14 individuals Trypanosoma cruzi-infected and from six uninfected individuals were analysed by immunohistochemistry. It was demonstrated that the number of tryptase-IR MCs in infected individuals increased when compared with controls, regardless of whether the individuals had megaoesophagus, whereas the number of chymase-IR MCs increased only in infected individuals without megaoesophagus. Negative correlations were observed between tryptase-IR MCs and the density of nerve fibres that expressed VIP or PGP 9.5-IR. The participation of chymase and tryptase in this type of immunopathology is discussed.
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Affiliation(s)
| | | | - André de Souza Lisboa
- Department of Morphology, ICB, Universidade Federal de Minas Gerais, 31.270-901, Brazil
| | | | - Débora d'Ávila Reis
- Department of Morphology, ICB, Universidade Federal de Minas Gerais, 31.270-901, Brazil.
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194
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Sanger GJ, Broad J, Kung V, Knowles CH. Translational neuropharmacology: the use of human isolated gastrointestinal tissues. Br J Pharmacol 2014; 168:28-43. [PMID: 22946540 DOI: 10.1111/j.1476-5381.2012.02198.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/08/2012] [Accepted: 08/23/2012] [Indexed: 12/22/2022] Open
Abstract
Translational sciences increasingly emphasize the measurement of functions in native human tissues. However, such studies must confront variations in patient age, gender, genetic background and disease. Here, these are discussed with reference to neuromuscular and neurosecretory functions of the human gastrointestinal (GI) tract. Tissues are obtained after informed consent, in collaboration with surgeons (surgical techniques help minimize variables) and pathologists. Given the difficulties of directly recording from human myenteric neurones (embedded between muscle layers), enteric motor nerve functions are studied by measuring muscle contractions/relaxations evoked by electrical stimulation of intrinsic nerves; responses are regionally dependent, often involving cholinergic and nitrergic phenotypes. Enteric sensory functions can be studied by evoking the peristaltic reflex, involving enteric sensory and motor nerves, but this has rarely been achieved. As submucosal neurones are more accessible (after removing the mucosa), direct neuronal recordings are possible. Neurosecretory functions are studied by measuring changes in short-circuit current across the mucosa. For all experiments, basic questions must be addressed. Because tissues are from patients, what are the controls and the influence of disease? How long does it take before function fully recovers? What is the impact of age- and gender-related differences? What is the optimal sample size? Addressing these and other questions minimizes variability and raises the scientific credibility of human tissue research. Such studies also reduce animal use. Further, the many differences between animal and human GI functions also means that human tissue research must question the ethical validity of using strains of animals with unproved translational significance.
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Affiliation(s)
- G J Sanger
- Neurogastroenterology Group, Blizard Institute, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, UK.
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195
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Yang J, Fox M, Cong Y, Chu H, Zheng X, Long Y, Fried M, Dai N. Lactose intolerance in irritable bowel syndrome patients with diarrhoea: the roles of anxiety, activation of the innate mucosal immune system and visceral sensitivity. Aliment Pharmacol Ther 2014; 39:302-11. [PMID: 24308871 DOI: 10.1111/apt.12582] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 09/14/2013] [Accepted: 11/19/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Irritable bowel syndrome patients with diarrhoea (IBS-D) often report intolerance to milk; however, the mechanism underlying these symptoms is unknown. AIM To assess the role of psychological factors, immune activation and visceral sensitivity on the development of lactose intolerance (LI) in IBS-D patients. METHODS Fifty-five IBS-D patients and 18 healthy controls (HCs) with lactase deficiency underwent a 20-g lactose hydrogen breath test (LHBT). Patients were categorised as lactose malabsorption (LM; malabsorption only) or LI [malabsorption plus increase in total symptom score (TSS). Measurements included (i) psychological status; (ii) enteric biopsies with quantification of mast cells (MCs), T-lymphocytes and enterochromaffin cells; (iii) serum cytokines; (iv) rectal sensitivity before and after lactose ingestion. RESULTS LI was more prevalent in IBS-D patients than HCs [25/55 (46%) vs. 3/18 (17%), P = 0.029]. IBS-D patients with LI had (i) higher levels of anxiety than those with LM (P = 0.017) or HCs (P = 0.006); (ii) increased mucosal MCs compared with LM (P = 0.006) and HCs (P < 0.001); (iii) raised serum TNF-α compared with LM (P = 0.034) and HCs (P < 0.001) and (iv) increased rectal sensitivity after lactose ingestion compared with LM (P < 0.001) or HCs (P < 0.001). Severity of abdominal symptoms after lactose ingestion was associated with the increase in visceral sensitivity after lactose intake (r = 0.629, P < 0.001), MCs (r = 0.650, P < 0.001) and anxiety (r = 0.519, P < 0.001). CONCLUSIONS IBS-D patients with lactose intolerence are characterised by anxiety, mucosal immune activation and increased visceral sensitivity after lactose ingestion. The presence of these biomarkers may indicate an IBS phenotype that responds to dietary therapy and/or mast cell stabilisers.
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Affiliation(s)
- J Yang
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China; Department of Gastroenterology, The First People's Hospital of Hangzhou, Hangzhou, China
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196
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Wang JJ, Jiang ZD, Zhang ZY, Wang ZB, Wang JS, Huang WB. Role of mast cells and protease activated receptor-2 in irritable bowel syndrome. Shijie Huaren Xiaohua Zazhi 2014; 22:327-332. [DOI: 10.11569/wcjd.v22.i3.327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the role of mast cells and protease activated receptor-2 (PAR-2) in irritable bowel syndrome (IBS).
METHODS: A total of 90 subjects were divided into a diarrhea-predominant irritable bowel syndrome (IBS-D) group (n = 60) and a normal control group (n = 30), all of them were selected from digestive outpatient department of Nanjing Hospital Affiliated to Nanjing Medical University from January 2012 to December 2012. The expression of mast cells and PAR-2 was detected by immunohistochemistry, and the expression of Occludin was detected by Western blot.
RESULTS: Immunohistochemistry analysis showed that compared with the normal control group, the expression of both mast cells and PAR-2 was significantly higher in the IBS-D group (5.20 ± 2.78 vs 1.40 ± 0.55, P < 0.05; 3.20 ± 1.64 vs 1.20 ± 0.45, P < 0.05). Western blot analysis indicated that the expression of Occludin decreased significantly in the IBS-D group compared with the normal control group (2108.33 ± 59.58 vs 3113.00 ± 77.74, P < 0.01).
CONCLUSION: Our study suggests that in IBS-D subjects, overexpressed and activated mast cells may stimulate PAR-2 and lead to the damage of intercellular tight junctions.
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197
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Jo Y. [The role of protease activated receptors and proteases in subtly inflamed diarrhea-predominant irritable bowel syndrome]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2014; 63:59-61. [PMID: 24605396 DOI: 10.4166/kjg.2014.63.1.59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Yunju Jo
- Department of Internal Medicine, Eulji University School of Medicine, Division of Gastroenterology, Eulji Hospital, Seoul, Korea
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198
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Cremon C, Carini G, De Giorgio R, Stanghellini V, Corinaldesi R, Barbara G. Intestinal dysbiosis in irritable bowel syndrome: etiological factor or epiphenomenon? Expert Rev Mol Diagn 2014; 10:389-93. [DOI: 10.1586/erm.10.33] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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199
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Abstract
The protease-activated receptors (PARs) play a pivotal role in inflammatory and nociceptive processes. PARs have raised considerable interest because of their capacity to regulate numerous aspects of viscera physiology and pathophysiology. The present article summarizes research on PARs and proteases as signalling molecules in visceral pain. In particular, experiments in animal models suggest that PAR2 is important for visceral hypersensitivity. Moreover, endogenous PAR2 agonists seem to be released by colonic tissue of patients suffering from irritable bowel syndrome, suggesting a role for this receptor in visceral pain perception. Thus, PARs, together with proteases that activate them, represent exciting targets for therapeutic intervention on visceral pain.
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Affiliation(s)
- Nicolas Cenac
- Inserm, U1043, Toulouse, F-31300, France ; ; CNRS, U5282, Toulouse, F-31300, France; ; Université de Toulouse, UPS, Centre de Physiopathologie de Toulouse Purpan (CPTP), Toulouse, F-31300, France
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200
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Role of enteric neurotransmission in host defense and protection of the gastrointestinal tract. Auton Neurosci 2013; 181:94-106. [PMID: 24412639 DOI: 10.1016/j.autneu.2013.12.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 12/11/2013] [Indexed: 12/24/2022]
Abstract
Host defense is a vital role played by the gastrointestinal tract. As host to an enormous and diverse microbiome, the gut has evolved an elaborate array of chemical and physicals barriers that allow the digestion and absorption of nutrients without compromising the mammalian host. The control of such barrier functions requires the integration of neural, humoral, paracrine and immune signaling, involving redundant and overlapping mechanisms to ensure, under most circumstances, the integrity of the gastrointestinal epithelial barrier. Here we focus on selected recent developments in the autonomic neural control of host defense functions used in the protection of the gut from luminal agents, and discuss how the microbiota may potentially play a role in enteric neurotransmission. Key recent findings include: the important role played by subepithelial enteric glia in modulating intestinal barrier function, identification of stress-induced mechanisms evoking barrier breakdown, neural regulation of epithelial cell proliferation, the role of afferent and efferent vagal pathways in regulating barrier function, direct evidence for bacterial communication to the enteric nervous system, and microbial sources of enteric neurotransmitters. We discuss these new and interesting developments in our understanding of the role of the autonomic nervous system in gastrointestinal host defense.
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