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- Gerdin, Linda, et al.
(författare)
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Acute psychological stress increases paracellular permeability and modulates immune activity in rectal mucosa of healthy volunteers
- 2023
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Ingår i: United European Gastroenterology journal. - : John Wiley & Sons Ltd. - 2050-6406 .- 2050-6414. ; 11:1, s. 31-41
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Tidskriftsartikel (refereegranskat)abstract
- Background Psychological stress and increased permeability are implicated as contributing factors in the initiation and worsening of gastrointestinal diseases. A link between stress and intestinal permeability has been shown in animal models as well as in human small intestine, but stress effects on the human colorectal mucosal barrier has not been reported. Objective To investigate the potential effects of acute psychological stress on colorectal mucosal barrier function and to explore stress-induced molecular events in the rectal mucosa under healthy conditions. Methods Endoscopic biopsies were taken from the rectosigmoid region of healthy volunteers, who had been subjected to dichotomous listening stress and after a control session, respectively. Paracellular and transcellular permeability were assessed in modified Ussing chambers. RNA expression (microarray technology confirmed by quantitative real-time polymerase chain reaction) and biological pathway analysis were used to investigate the local mucosal response to acute stress. Results Dichotomous listening stress induced a subjective and objective stress response, and significantly increased paracellular but not transcellular permeability. We also identified a stress-induced reduction in RNA expression of genes related to immune cell activation and maturation (CR2, CD20, TCLA1, BANK1, CD22, FDCSP), signaling molecules of homing of immune cells to the gut (chemokines: CCL21, CXCL13, and CCL19, and receptors: CCR7, CXCR5), and innate immunity (DUOX2). Eight of the 10 top down-regulated genes are directly involved in B cell activation, signaling and migration. The systemic stress response correlated positively with paracellular permeability and negatively with DUOX2 expression. Conclusion Dichotomous listening stress increases paracellular permeability and modulates immune cell activity in the rectal mucosa. Further studies are warranted to identify the primary mechanisms of stress-mediated reduction of mucosal defensive activity and barrier dysfunction, and their potential implications for gastrointestinal disorders.
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| 2. |
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| 3. |
- Persborn, Mats, et al.
(författare)
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Effects of probiotics (Ecologic 825) on barrier function during maintenance treatment for severe pouchitis
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background : About 10-15% of patients with an ileoanal pouch develop a severe, form of pouchitis that necessitates long and/or frequent use of antibiotics and in rare cases even pouch excision. Probiotics have been shown to reduce the risk of recurrence after induction treatment with antibiotics. The mechanisms behind the positive effects of probiotics are not fully understood. The aim of our study was to examine the mucosal barrier function in relation to pouchitis, before and after treatment with probiotics. Methods: 16 patients with a history of severe pouchitis underwent endoscopy with biopsies of the pouch on three occasions: Once during active pouchitis, second after 4 weeks of treatment with antibiotics until clinical remission and third after eight weeks of probiotic treatment. 13 controls with an ileoanal pouch with no recent history of pouchitis were used. The biopsies were mounted in Ussing chambers and mucosal barrier function was assessed by electrophysiology, transmucosal uptake of E coli K12, permeability to Cr-EDTA and Horseradish peroxidase (HRP). Pouchitis Disease Activity Index (PDAI) was used in all subjects. Results: PDAI was significantly improved after treatment with antibiotics and probiotics. There was a significant difference in E. coli K12 passage before treatment compared to controls (3.7 units (3.4-8.5) vs 1.7 units (1.0-2.4) p< 0.01). E. coli K12 passage did not change after antibiotic treatment (5.0 units (3.3-7.1) p = ns vs controls). In contrast a significant reduction in bacterial uptake was seen after probiotics (2.2 units (1.8-3.3) p< 0.05). Likewise, a significant normalization of HRP flux was seen after probiotic treatment. Pouchitis did not affect paracellular permability or electrophysiology. Conclusion: Probiotic treatment restored the increased permeation to E. coli and HRP in patients with chronic pouchitis. This could be an important factor behind the positive effects of probiotics in patients with chronic pouchitis.
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| 4. |
- Persborn, Mats, 1981-
(författare)
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Studies of barrier function in patients with ulcerative colitis and pouchitis
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background and aim: The cause of ulcerative colitis (UC) is largely unknown. However, there is a presumed genetic component to susceptibility and altered intestinal barrier function has been implicated in the pathophysiology of ulcerative colitis. There is evidence that the increased intestinal permeability in IBD is partly controlled by delicate intercellular circuits in the colonic tissue linked to the enteric nervous system. Little is, however, known about how this is regulated in detail.Ileal pouch-anal anastomosis (IPAA) is a good surgical reconstructive option in UC patients after proctocolectomy. However 10-15% of IPAA patients develop a severe and recurrent inflammation in the constructed pouch. The standard treatment for pouchitis is long and/or frequent use of antibiotics. Probiotics have been shown to reduce the risk of recurrence of pouchitis after induction treatment with antibiotics.The aim was to characterize macromolecular permeability in non inflamed colon of UC and elucidate the role of cholinergic signaling, mast cells and eosinophils in the regulation of the human colonic permeability. Furthermore, we examine the mucosal barrier function in relation to pouchitis, before and after treatment with probiotics.Material and methods: In the first study 23 UC patients in remission and 53 healthy volunteers were included. Biopsies from the sigmoid colon were assed for macromolecular permeability (horseradish peroxidase (HRP) and 51CrEDTA) and electrophysiology during challenge with carbachol. Experiments were repeated with CRF receptor antagonists, carbachol receptor antagonists and mast cell stabilizers in Ussing chambers. Further, pouch biopsies from 16 IPAA patients with pouchitis and 13 IPAA controls were assed in Ussing chambers for macromolecular permeability and electrophysiology as above. In addition E. coli K12 were used to assess the barrier to bacteria. Biopsies were taken on three occasions; before treatment, after antibiotics and after probiotics. Pouchitis Disease Activity Index (PDAI) was used in all subjects.Results: Colonic tissues from UC patients had significant increase in permeability to protein antigens compared with controls. Permeability was normalized by atropine, α-helical CRF(9-41) and lodoxamide. Eosinophils were increased in number in UC tissues, expressed M2 and M3 muscarinic receptors and showed immunoreactivity to CRF. In pouchitis patients, PDAI was significantly improved after treatment with antibiotics and probiotics. There was a significantly enhanced passage of E. coli K12 and HRP in patients with active pouchitis, which was unchanged during treatment with antibiotics, but significantly normalized by probiotics.Conclusions and discussion: We identified a neuroimmune intercellular circuit (from cholinergic nerves, via eosinophils to mast cells) that mediates colonic mucosal barrier dysfunction in UC patients. Furthermore we found that probiotics restored the increased permeation to E. coli and HRP in patients with pouchitis. Pouchitis, resembling symptoms in active UC, may well constitute a good model to study acquired intestinal barrier dysfunction in IBD.
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| 5. |
- Persborn, Mats, et al.
(författare)
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The effects of probiotics on barrier function and mucosal pouch microbiota during maintenance treatment for severe pouchitis in patients with ulcerative colitis
- 2013
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Ingår i: Alimentary Pharmacology and Therapeutics. - : Wiley-Blackwell. - 0269-2813 .- 1365-2036. ; 38:7, s. 772-783
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Tidskriftsartikel (refereegranskat)abstract
- Background less thanbrgreater than less thanbrgreater thanA total of 10-15% of patients with an ileoanal pouch develop severe pouchitis necessitating long-term use of antibiotics or pouch excision. Probiotics reduce the risk of recurrence of pouchitis, but mechanisms behind these effects are not fully understood. less thanbrgreater than less thanbrgreater thanAim less thanbrgreater than less thanbrgreater thanTo examine mucosal barrier function in pouchitis, before and after probiotic supplementation and to assess composition of mucosal pouch microbiota. less thanbrgreater than less thanbrgreater thanMethods less thanbrgreater than less thanbrgreater thanSixteen patients with severe pouchitis underwent endoscopy with biopsies of the pouch on three occasions: during active pouchitis; clinical remission by 4 weeks of antibiotics; after 8 weeks of subsequent probiotic supplementation (Ecologic 825, Winclove, Amsterdam, the Netherlands). Thirteen individuals with a healthy ileoanal pouch were sampled once as controls. Ussing chambers were used to assess transmucosal passage of Escherichia coli K12, permeability to horseradish peroxidase (HRP) and Cr-51-EDTA. Composition and diversity of the microbiota was analysed using Human Intestinal Tract Chip. less thanbrgreater than less thanbrgreater thanResults less thanbrgreater than less thanbrgreater thanPouchitis Disease Activity Index (PDAI) was significantly improved after antibiotic and probiotic supplementation. Escherichia coli K12 passage during active pouchitis [3.7 (3.4-8.5); median (IQR)] was significantly higher than in controls [1.7 (1.0-2.4); P andlt; 0.01], did not change after antibiotic treatment [5.0 (3.3-7.1); P = ns], but was significantly reduced after subsequent probiotic supplementation [2.2 (1.7-3.3); P andlt; 0.05]. No significant effects of antibiotics or probiotics were observed on composition of mucosal pouch microbiota; however, E. coli passage correlated with bacterial diversity (r = -0.40; P = 0.018). Microbial groups belonging to Bacteroidetes and Clostridium clusters IX, XI and XIVa were associated with healthy pouches. less thanbrgreater than less thanbrgreater thanConclusions less thanbrgreater than less thanbrgreater thanProbiotics restored the mucosal barrier to E. coli and HRP in patients with pouchitis, a feasible factor in prevention of recurrence during maintenance treatment. Restored barrier function did not translate into significant changes in mucosal microbiota composition, but bacterial diversity correlated with barrier function.
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| 6. |
- Wallon, Conny, et al.
(författare)
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Eosinophils Express Muscarinic Receptors and Corticotropin-Releasing Factor to Disrupt the Mucosal Barrier in Ulcerative Colitis
- 2011
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Ingår i: Gastroenterology. - : Elsevier Science B.V. Amsterdam. - 0016-5085 .- 1528-0012. ; 140:5, s. 1597-1607
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND andamp; AIMS: Altered intestinal barrier function has been implicated in the pathophysiology of ulcerative colitis (UC) in genetic, functional, and epidemiological studies. Mast cells and corticotropinreleasing factor (CRF) regulate the mucosal barrier in human colon. Because eosinophils are often increased in colon tissues of patients with UC, we assessed interactions among mast cells, CRF, and eosinophils in the mucosal barrier of these patients. METHODS: Transmucosal fluxes of protein antigens (horseradish peroxidase) and paracellular markers (51Cr-EDTA, fluorescein isothiocyanate-dextran 4000) were studied in noninflamed, colonic mucosal biopsy samples collected from 26 patients with UC and 53 healthy volunteers (controls); samples were mounted in Ussing chambers. We also performed fluorescence and electron microscopy of human tissue samples, assessed isolated eosinophils, and performed mechanistic studies using in vitro cocultured eosinophils (15HL-60), mast cells (HMC-1), and a colonic epithelial cell line (T84). RESULTS: Colon tissues from patients with UC had significant increases in permeability to protein antigens compared with controls. Permeability was blocked by atropine (a muscarinic receptor antagonist), alpha-helical CRF(9-41) (a CRF receptor antagonist), and lodoxamide (a mast-cell stabilizer). Eosinophils were increased in number in UC tissues (compared with controls), expressed the most M2 and M3 muscarinic receptors of any mucosal cell type, and had immunoreactivity to CRF. In coculture studies, carbachol activation of eosinophils caused production of CRF and activation of mast cells, which increased permeability of T84 epithelial cells to macromolecules. CONCLUSIONS: We identified a neuroimmune intercellular circuit (from cholinergic nerves, via eosinophils to mast cells) that mediates colonic mucosal barrier dysfunction in patients with UC. This circuit might exacerbate mucosal inflammation.
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