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  • 1.
    Bednarska, Olga
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Walter, Susanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Gastroentorology.
    Casado-Bedmar, Maite
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ström, Magnus
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Gastroentorology.
    Salvo-Romero, Eloisa
    University of Autonoma Barcelona, Spain.
    Vicario, Maria
    University of Autonoma Barcelona, Spain.
    Mayer, Emeran A.
    University of Calif Los Angeles, CA 90095 USA.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Vasoactive Intestinal Polypeptide and Mast Cells Regulate Increased Passage of Colonic Bacteria in Patients With Irritable Bowel Syndrome2017In: Gastroenterology, ISSN 0016-5085, E-ISSN 1528-0012, Vol. 153, no 4, p. 948-+Article in journal (Refereed)
    Abstract [en]

    BACKGROUND amp; AIMS: Irritable bowel syndrome (IBS) is associated with intestinal dysbiosis and symptoms of IBS develop following gastroenteritis. We aimed to study the passage of live bacteria through the colonic epithelium, and determine the role of mast cells (MCs) and vasoactive intestinal polypeptide (VIP) in barrier regulation in IBS and healthy individuals. METHODS: Colon biopsies from 32 women with IBS and 15 age-matched healthy women (controls) were mounted in Ussing chambers; we measured numbers of fluorescently labeled Escherichia coli HS and Salmonella typhimurium that passed through from the mucosal side to the serosal side of the tissue. Some biopsies were exposed to agents that block the VIP receptors (VPAC1 and VPAC2) or MCs. Levels of VIP and tryptase were measured in plasma and biopsy lysates. Number of MCs and MCs that express VIP or VIP receptors were quantified by immunofluorescence. Biopsies from an additional 5 patients with IBS and 4 controls were mounted in chambers and Salmonella were added; we studied passage routes through the epithelium by transmission electron microscopy and expression of tight junctions by confocal microscopy. RESULTS: In colon biopsies from patients with IBS, larger numbers of E coli HS and S typhimurium passed through the epithelium than in biopsies from controls (P amp;lt;.0005). In transmission electron microscopy analyses, bacteria were found to cross the epithelium via only the transcellular route. Bacterial passage was reduced in biopsies from patients with IBS and controls after addition of antibodies against VPACs or ketotifen, which inhibits MCs. Plasma samples from patients with IBS had higher levels of VIP than plasma samples from controls. Biopsies from patients with IBS had higher levels of tryptase, larger numbers of MCs, and a higher percentage of MCs that express VPAC1 than biopsies from controls. In biopsies from patients with IBS, addition of Salmonella significantly reduced levels of occludin; subsequent addition of ketotifen significantly reversed this effect. CONCLUSIONS: We found that colonic epithelium tissues from patients with IBS have increased translocation of commensal and pathogenic live bacteria compared with controls. The mechanisms of increased translocation include MCs and VIP.

  • 2.
    Beeckmans, Dorien
    et al.
    Katholieke Univ Leuven, Belgium.
    Farre, Ricard
    Katholieke Univ Leuven, Belgium.
    Riethorst, Danny
    Katholieke Univ Leuven, Belgium.
    Keita, Åsa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Augustijns, Patrick
    Katholieke Univ Leuven, Belgium.
    Söderholm, Johan D
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Vanuytsel, Tim
    Katholieke Univ Leuven, Belgium.
    Vanheel, Hanne
    Katholieke Univ Leuven, Belgium.
    Tack, Jan
    Katholieke Univ Leuven, Belgium.
    Relationship between bile salts, bacterial translocation, and duodenal mucosal integrity in functional dyspepsia2020In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, article id e13788Article in journal (Refereed)
    Abstract [en]

    Background Functional dyspepsia (FD) is a complex disorder, in which multiple mechanisms underlie symptom generation, including impaired duodenal barrier function. Moreover, an altered duodenal bile salt pool was recently discovered in patients with FD. We aimed to evaluate the relationship between bile salts, bacterial translocation, and duodenal mucosal permeability in FD. Methods Duodenal biopsies from patients with FD and healthy volunteers (HV) were mounted in Ussing chambers to measure mucosal resistance and bacterial passage in the absence and presence of fluorescein-conjugated Escherichia coli and glyco-ursodeoxycholic acid (GUDCA) exposure. In parallel, duodenal fluid aspirates were collected from patients and bile salts were analyzed. Key results The transepithelial electrical resistance of duodenal biopsies from patients was lower compared with HV (21.4 +/- 1.3 omega.cm(2) vs. 24.4 +/- 1.2 omega.cm(2); P = .02; N = 21). The ratio of glyco-cholic and glyco-chenodeoxycholic acid (GCDCA) to tauro- and GUDCA correlated positively with transepithelial electrical resistance in patients. Glyco-ursodeoxycholic acid slightly altered the mucosal resistance, resulting in similar values between patient and healthy biopsies (22.1 +/- 1.0 omega.cm(2) vs. 23.0 +/- 1.0 omega.cm(2); P = .5). Bacterial passage after 120 minutes was lower for patient than for healthy biopsies (0.0 [0.0-681.8] vs. 1684.0 [0.0-4773.0] E coli units; P = .02). Glyco-ursodeoxycholic acid increased bacterial passage in patient biopsies (102.1 [0.0-733.0] vs. 638.9 [280.6-2124.0] E coli units; P = .009). No correlation was found between mucosal resistance and bacterial passage. Conclusions amp; inferences Patients with FD displayed decreased duodenal mucosal resistance associated with bile salts, however, not associated with bacterial passage in vitro. In addition, the hydrophilic bile salt glyco-ursodeoxycholic acid abolished differences in mucosal resistance and bacterial passage between patient and control group.

  • 3.
    Carlander, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Johansson, Kenth
    Lasarettet Västervik.
    Lindström, Sivert
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of cell biology.
    Keita, Åsa
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of surgery.
    Jiang, Chonghe
    Linköping University, Department of Biomedicine and Surgery, Division of cell biology. Linköping University, Faculty of Health Sciences.
    Nordborg, C
    Department of Pathology, Sahlgrenska University Hospital, Göteborg, Sweden.
    Comparison of experimental nerve injury caused by ultrasonically activated scalpel and electrosurgery2005In: British Journal of Surgery, ISSN 0007-1323, E-ISSN 1365-2168, Vol. 92, no 6, p. 772-777Article in journal (Refereed)
    Abstract [en]

    Background: Iatrogenic nerve injury caused by heat from dissection instruments is a significant problem in many areas of surgery. The aim of the present study was to compare the risk of nerve injury for three different dissection instruments: monopolar and bipolar electrosurgery (ES) and an ultrasonically activated (US) instrument. Methods: The biceps femoris muscle was cut in a standard manner just adjacent to the sciatic nerve using monopolar ES, bipolar ES or US shears. A total of 73 functional experiments were conducted in which the nerve was isolated, divided proximally, and stimulated supramaximally in 37 anaesthetized rats. The electromyographic (EMG) potential was recorded distally before and after each experiment. Nerve dysfunction was defined as more than 10 per cent loss of the evoked EMG potential. Fifty-nine nerves were examined histologically after dissection with the different instruments. The extent of heat damage was determined in four nerves that were divided with ES bipolar scissors and five that were divided with US shears. Results: Reduction in the EMG potential was significantly more frequent in the monopolar ES group than in the US group. Morphological examination also showed significantly less nerve damage in the US group. Conclusion: US instruments may be safer than ES for dissection close to nerves. Copyright © 2005 British Journal of Surgery Society Ltd.

  • 4.
    Carlsson, Anders H.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Yakymenko, Olena
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Olivier, Isabelle
    External - unknown .
    Håkansson, Fathima
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Postma, Emily
    External - unknown .
    Keita, Asa V.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Soderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Faecalibacterium prausnitzii supernatant improves intestinal barrier function in mice DSS colitis2013In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, E-ISSN 1502-7708, Vol. 48, no 10, p. 1136-1144Article in journal (Refereed)
    Abstract [en]

    Objective. The intestinal microbiota plays a substantial role in the pathogenesis of inflammatory bowel disease (IBD). Faecalibacterium prausnitzii (FP) is underrepresented in IBD patients and have been suggested to have anti-inflammatory effects in mice. Increased intestinal permeability is common in IBD but the relationship between FP and intestinal barrier function has not been investigated. Our aim was to study treatment with FP supernatant on intestinal barrier function in a dextran sodium sulfate (DSS) colitis mice model. Material and methods. C57BL/6 mice received 3% DSS in tap water ad libitum during five days to induce colitis. From day 3 the mice received a daily gavage with FP supernatant or broth during seven days. Ileum and colon were mounted in Ussing chambers for permeability studies with Cr-51-EDTA and Escherichia coli K-12. Colon was saved for Western blot analyses of tight junction proteins. Results. DSS-treated mice showed significant weight loss and colon shortening. Gavage with FP supernatant resulted in a quicker recovery after DSS treatment and less extensive colonic shortening. Ileal mucosa of DSS mice showed a significant increase in Cr-51-EDTA-passage compared to controls. Cr-51-EDTA passage was significantly decreased in mice receiving FP supernatant. No significant differences were observed in passage of E. coli K12. Western blots showed a trend to increased claudin-1 and claudin-2 expressions in DSS mice. Conclusions. Supernatant of FP enhances the intestinal barrier function by affecting paracellular permeability, and may thereby attenuate the severity of DSS-induced colitis in mice. These findings suggest a potential role of FP in the treatment of IBD.

  • 5.
    Casado Bedmar, Maite
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Keita, Åsa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Potential neuro-immune therapeutic targets in irritable bowel syndrome2020In: Therapeutic Advances in Gastroenterology, ISSN 1756-283X, E-ISSN 1756-2848, Vol. 13, article id 1756284820910630Article, review/survey (Refereed)
    Abstract [en]

    Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder characterized by recurring abdominal pain and disturbed bowel habits. The aetiology of IBS is unknown but there is evidence that genetic, environmental and immunological factors together contribute to the development of the disease. Current treatment of IBS includes lifestyle and dietary interventions, laxatives or antimotility drugs, probiotics, antispasmodics and antidepressant medication. The gut-brain axis comprises the central nervous system, the hypothalamic pituitary axis, the autonomic nervous system and the enteric nervous system. Within the intestinal mucosa there are close connections between immune cells and nerve fibres of the enteric nervous system, and signalling between, for example, mast cells and nerves has shown to be of great importance during GI disorders such as IBS. Communication between the gut and the brain is most importantly routed via the vagus nerve, where signals are transmitted by neuropeptides. It is evident that IBS is a disease of a gut-brain axis dysregulation, involving altered signalling between immune cells and neurotransmitters. In this review, we analyse the most novel and distinct neuro-immune interactions within the IBS mucosa in association with already existing and potential therapeutic targets.

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  • 6.
    Casado Bedmar, Maria Teresa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Heil, Stéphanie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Myrelid, Pär
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Upregulation of intestinal mucosal mast cells expressing VPAC1 in close proximity to vasoactive intestinal polypeptide in inflammatory bowel disease and murine colitis2019In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, Vol. 31, no 3, article id e13503Article in journal (Refereed)
    Abstract [en]

    Background

    Mast cells (MCs) and vasoactive intestinal polypeptide (VIP) have been proposed as regulators of the intestinal barrier and inflammation. Our aim was to map the distribution in inflammatory bowel disease (IBD) and murine colitis.

    Methods

    MCs, VIP, and VIP‐receptors (VPACs) were quantified by immunofluorescence and enzyme‐immunoassay (EIA) in ileal tissues (villus epithelium (VE) and adjacent VE, ie, VE next to the follicle‐associated epithelium, (FAE)) from Crohn's disease (CD; n = 16) and non‐IBD patients, and in colonic specimens of ulcerative colitis (UC; n = 12) and healthy controls (HCs). In addition, VIP levels were measured in plasma from HCs, non‐IBD, and IBD in remission (CD n = 30; UC n = 30). Colon, ileum, and plasma from mice with dextran sulfate sodium (DSS)‐induced colitis and control mice were analyzed likewise.

    Key Results

    FAE‐adjacent VE in ileum of CD possessed more MCs (P < 0.05) and MCs expressing VPAC1 (P < 0.05), but not VPAC2, compared to controls. Both adjacent and regular VE of CD had more MCs co‐localizing/in close proximity to VIP (P < 0.05). In UC colon, more MCs (P < 0.0005), MCs close to VIP (P < 0.0005), and MCs expressing VPAC1 (P < 0.05) were found compared to controls. VIP levels were elevated in plasma from CD and UC compared to controls (P < 0.0005). Colon of DSS mice showed more MCs and MCs close to VIP (P < 0.05) compared to control mice. In vitro experiments revealed MCs expressing VPACs and internalized VIP after 120 minutes of VIP‐stimulation.

    Conclusions and Inferences

    Communication between MCs and VIP is upregulated during IBD and mice colitis. In CD patients, the epithelium next to FAE seems to be more involved than the surrounding VE, suggesting increased MC‐VIP‐interactions in this intestinal region.

  • 7.
    Christerson, Ulrika
    et al.
    Linnaeus Univ, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Tinnerfelt Winberg, Martin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Gustafson-Svard, Christina
    Linnaeus Univ, Sweden.
    Possible Involvement of Intracellular Calcium-Independent Phospholipase A2 in the Release of Secretory Phospholipases from Mast Cells: Increased Expression in Ileal Mast Cells of Crohns Disease2019In: CELLS, ISSN 2073-4409, Vol. 8, no 7, article id 672Article in journal (Refereed)
    Abstract [en]

    Increased activity of secretory phospholipases A(2) (sPLA(2)) type-II was previously observed in ileum of Crohns disease (CD). Our aims were to explore the involvement of calcium-independent (i)PLA(2 beta) in the release of sPLA(2)s from the human mast cell (MC) line (HMC-1) and investigate expressions of cytosolic (c)PLA(2) alpha, iPLA(2)beta, sPLA(2)-IIA and sPLA(2)-V in MCs of CD ileum. The release of sPLA(2) was investigated in HMC-1 by immunocytochemistry and ELISA. The expression intensities of PLA(2)s in mucosal MCs, and the proportion of PLA(2)-positive MCs, were investigated in normal ileum and in ileum from patients with CD by immunohistochemistry. The calcium ionophore-stimulated release of sPLA(2)-IIA and sPLA(2)-V from HMC-1 was reduced by the iPLA(2)-inhibitor bromoenol lactone. All four PLA(2)s were detectable in mucosal MCs, both in normal ileum and in CD, but the proportion of iPLA(2)beta-containing mucosal MCs and the expression intensity of sPLA(2)-IIA was increased in CD. Results indicate that iPLA(2)beta is involved in the secretion of sPLA(2)s from HMC-1, and suggest that iPLA(2)beta-mediated release of sPLA(2) from intestinal MCs may contribute to CD pathophysiology. Ex vivo studies on isolated mucosal mast cells are however needed to clarify the precise role of MC PLA(2)s in the inflammatory processes of CD.

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  • 8.
    Christerson, Utrika
    et al.
    University of Kalmar.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Gustafson-Svard, Christina
    University of Kalmar.
    Increased expression of protease-activated receptor-2 in mucosal mast cells in Crohns ileitis2009In: JOURNAL OF CROHNS and COLITIS, ISSN 1873-9946, Vol. 3, no 2, p. 100-108Article in journal (Refereed)
    Abstract [en]

    Background and aims: Activation of protease-activated receptor-2 (PAR-2) may stimulate various events of importance in inflammatory processes, including release of inflammatory mast cell mediators. PAR-2 is frequently up-regulated during inflammatory conditions, but it is not known if the expression is altered in Crohns disease. The aim of the present study was to investigate the ileal mucosal PAR-2 expression in Crohns ileitis, with particular emphasis on the expression in ileal mucosal mast cells. Methods: Surgical specimens from the distal ileum were collected from patients with Crohns ileitis and patients with colonic cancer as controls. The overall expression of PAR-2 was investigated by Western blot, and the presence of PAR-2 expressing mucosal mast cells by immunohistochemistry and cell counting. The effect of tumor necrosis factor-alpha (TNF-alpha) on the PAR-2 expression in a human mast cell tine (HMC-1) was investigated by RT-PCR and immunocytochemistry. Results: In Crohns specimens, the fraction of PAR-2-expressing mucosal. mast cells was increased about 2.5 times (P andlt; 0.001; n = 14) compared with specimens from control patients (n = 6). No difference was found between inflamed (n = 6) and uninflamed Crohns specimens (P andgt; 0.05; n = 8). Exposure to TNF-alpha for 48 h up-regulated PAR-2 mRNA and protein expression in the HMC-1 cell line. Conclusion: PAR-2 is up-regulated on ileal mucosal mast cells in Crohns ileitis, possibly due to the action of inflammatory cytokines, such as TNF-alpha. This may contribute to perpetuating the inflammatory process in the intestinal mucosa in Crohns ileitis.

  • 9.
    Christerson, Utrika
    et al.
    Kalmar University .
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Gustafson-Svard, Christina
    Kalmar University .
    Potential role of protease-activated receptor-2-stimulated activation of cytosolic phospholipase A(2) in intestinal myofibroblast proliferation: Implications for stricture formation in Crohns disease2009In: JOURNAL OF CROHNS and COLITIS, ISSN 1873-9946, Vol. 3, no 1, p. 15-24Article in journal (Refereed)
    Abstract [en]

    Background and aims: Myofibroblast hyperplasia contributes to muscularis mucosae thickening and stricture formation in Crohns disease (CD). Protease-activated receptor-2 (PAR-2) and cytosolic phospholipase A(2) (cPLA(2)) are known regulators of cell growth, but their significance in intestinal myofibroblast proliferation remain to be elucidated. The principle aims of the present study were to investigate if PAR-2 is expressed in the expanded muscularis mucosa in ileal CD specimens, if inflammatory cytokines may stimulate PAR-2 expression in intestinal myofibroblasts, and if PAR-2 and cPLA(2). may regulate intestinal myofibroblast growth.

    Methods: Immunohistochemistry was used for detection of PAR-2 in ileal CD specimens. Studies on PAR-2 expression, PLA(2) activation and cell growth were performed in a human intestinal myofibroblast cell tine, CCD-18Co. PAR-2 expression was investigated by RT-PCR and immunocytochemistry. PLA(2) activity was analyzed by quantification of released C-14-arachidonic acid (C-14-AA). Cell growth was examined by H-3-thymidine incorporation and cell counting.

    Results: The thickened muscularis mucosae of the CD specimens showed strong PAR-2 expression. In cultured myofibroblasts, tumor necrosis factor-alpha (TNF-alpha) up-regulated PAR-2 mRNA and protein, and potentiated PAR-2-stimutated C-14-AA release by two known PAR-2 activators, trypsin and SLIGRL-NH2. The release of C-14-AA was dependent on cPLA(2). Trypsin stimulated the proliferation of serum-starved cells, and inhibition of cPLA(2) reduced normal cell growth and abolished the growth-promoting effect of trypsin.

    Conclusions: The results suggest that PAR-2-mediated cPLA(2) activation might be of importance in intestinal myofibroblast proliferation. The results also point to the possibility that PAR-2 upregulation by inflammatory cytokines, like TNF-alpha, may modulate this effect.

  • 10.
    Da Silva, Stéphanie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Keita, Åsa V.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Mohlin, Sofie
    Translational Cancer Research, Cancer Center at Medicon Village, Lund University, Lund, Sweden.
    Påhlman, Sven
    Translational Cancer Research, Cancer Center at Medicon Village, Lund University, Lund, Sweden.
    Théodorou, Vassilia
    Toxalim UMR 1331 INRA/INP/UPS Neuro-Gastroenterology and Nutrition Unit, Toulouse, France.
    Påhlman, Ingrid
    Albireo AB, Arvid Wallgrens Backe, Gothenburg, Sweden.
    Mattson, Jan P.
    Albireo AB, Arvid Wallgrens Backe, Gothenburg, Sweden.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    A novel topical PPARγ agonist induces PPARγ-activity in ulcerative colitis mucosa and prevents and reverses inflammation in induced-colitis models2018In: Inflammatory Bowel Diseases, ISSN 1078-0998, E-ISSN 1536-4844, Vol. 24, no 4, p. 792-805Article in journal (Refereed)
    Abstract [en]

    Background: Peroxisome proliferator-activated receptor-gamma (PPARγ) exerts anti-inflammatory effects and is therefore a potential target in ulcerative colitis (UC). A novel PPARγ agonist (AS002) developed for local action was evaluated ex vivo in biopsies from UC patients and in vivo in mice with low-grade dextran sodium sulfate (DSS)- and trinitrobenzene sulfonic acid (TNBS)-induced colitis.Methods: Colonic biopsies from UC patients (n = 18) and healthy controls (n = 6) were incubated with AS002 or rosiglitazone (positive control) to measure mRNA expression of the PPARγ-responsive gene ADIPOPHILIN and protein levels of UC-related cytokines (enzyme-linked immunosorbent assay). AS002 absorption was determined in the colonic mucosa of UC patients. DSS-colitis mice received PPARγ agonists or vehicle daily by intrarectal administration starting 2 days before induction of colitis (preventive) or from days 3 to 8 (curative). Myeloperoxidase (MPO) and cytokine levels in colonic mucosa were determined. In addition, AS002 effects were studied in TNBS colitis.Results: AS002 displayed an absorption pattern of a lipophilic drug totally metabolized in the mucosa. AS002 and rosiglitazone increased ADIPOPHILIN mRNA expression (3-fold) and decreased TNF-α, IL-1β, and IL-13 levels in human UC biopsies. In DSS, in both preventive and curative treatment and in TNBS colitis, AS002 protected against macroscopic and histological damage and lowered MPO and TNF-α, IL-1β, and IL-13 levels.Conclusions: AS002 triggers anti-inflammatory PPARγ activity in the human colonic mucosa of UC patients and prevents and reverses colitis in mice. Our data suggest that AS002 has potential for topical maintenance treatment of UC, which warrants further studies in vivo in patients.

  • 11.
    Ermund, Anna
    et al.
    University of Gothenburg, Sweden .
    Gustafsson, Jenny K.
    University of Gothenburg, Sweden .
    Hansson, Gunnar C.
    University of Gothenburg, Sweden .
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Mucus Properties and Goblet Cell Quantification in Mouse, Rat and Human Ileal Peyers Patches2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 12, p. 83688-Article in journal (Refereed)
    Abstract [en]

    Peyers patches (PPs) are collections of lymphoid follicles in the small intestine, responsible for scanning the intestinal content for foreign antigens such as soluble molecules, particulate matter as well as intact bacteria and viruses. The immune cells of the patch are separated from the intestinal lumen by a single layer of epithelial cells, the follicle-associated epithelium (FAE). This epithelium covers the dome of the follicle and contains enterocyte-like cells and M cells, which are particularly specialized in taking up antigens from the gut. However, the presence and number of goblet cells as well as the presence of mucus on top of the FAE is controversial. When mouse ileal PPs were mounted in a horizontal Ussing-type chamber, we could observe a continuous mucus layer at mounting and new, easily removable mucus was released from the villi on the patch upon stimulation. Confocal imaging using fluorescent beads revealed a penetrable mucus layer covering the domes. Furthermore, immunostaining of FAE from mice, rats and humans with a specific antibody against the main component of intestinal mucus, the MUC2 mucin, clearly identify mucin-containing goblet cells. Transmission electron micrographs further support the identification of mucus releasing goblet cells on the domes of PPs in these species.

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  • 12.
    Ganda Mall, John-Peter
    et al.
    School of Medical Sciences, Nutrition-Gut-Brain Interactions Research Centre, Örebro University, Örebro, Sweden.
    Casado-Bedmar, Maite
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Winberg, Martin E.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Brummer, Robert J.
    School of Medical Sciences, Nutrition-Gut-Brain Interactions Research Centre, Örebro University, Örebro, Sweden.
    Schoultz, Ida
    School of Medical Sciences, Nutrition-Gut-Brain Interactions Research Centre, Örebro University, Örebro, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. School of Medical Sciences, Nutrition-Gut-Brain Interactions Research Centre, Örebro University, Örebro, Sweden.
    A ß-Glucan-Based Dietary Fiber Reduces Mast Cell-Induced Hyperpermeability in Ileum From Patients With Crohns Disease and Control Subjects2018In: Inflammatory Bowel Diseases, ISSN 1078-0998, E-ISSN 1536-4844, Vol. 24, no 1, p. 166-178Article in journal (Refereed)
    Abstract [en]

    Administration of ß-glucan has shown immune-enhancing effects. Our aim was to investigate whether ß-glucan could attenuate mast cell (MC)-induced hyperpermeability in follicle-associated epithelium (FAE) and villus epithelium (VE) of patients with Crohns disease (CD) and in noninflammatory bowel disease (IBD)-controls. Further, we studied mechanisms of ß-glucan uptake and effects on MCs in vitro.

  • 13. Gullberg, Elisabet
    et al.
    Keita, Åsa
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of surgery.
    Salim, Sa´ad
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of surgery.
    Andersson, Margaretha
    Caldwell, Karin D
    Söderholm, Johan D
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of surgery. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Artursson, Per
    Identification of cell adhesion molecules in the human follicle-associated epithelium that improve nanoparticle uptake into the Peyer's patches2006In: Journal of Pharmacology and Experimental Therapeutics, ISSN 0022-3565, E-ISSN 1521-0103, Vol. 319, no 2, p. 632-639Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to identify cell adhesion molecules that could serve as targets of the human follicle-associated epithelium (FAE) overlying Peyer's patches and to assess nanoparticle uptake levels across this epithelium. We first studied the expression of the mouse M-cell marker β1- integrin and used a model of human FAE derived from intestinal epithelial Caco-2 cells and Raji B-cells to identify additional potential targets by cDNA array. The protein expression of potential targets in the model FAE and in human ileal FAE tissues was quantified by immunofluorescence. Integrin targeting was studied by investigating the transport of Arg-Gly-Asp (RGD)-coated (integrin-binding), Arg-Gly-Glu (RGE)-coated (nonintegrin-binding), and uncoated nanoparticles across ileal specimens mounted in Ussing chambers. Both β1- integrin and the cell adhesion molecule CD9 were more abundantly expressed in the model and human FAE compared with the Caco-2 control cells or villus epithelium (VE). Uncoated nanoparticles were not taken up across either FAE or VE. General integrin targeting with RGD improved the nanoparticle transport dramatically across the FAE and to a lower extent across the VE. Compared with RGE, RGD improved transport 4-fold across the FAE. There was no difference in the transport of RGD- and RGE-coated nanoparticles across the VE. In conclusion, β1-integrin and CD9 were identified as targets in human FAE. The difference in RGD- and RGE-mediated transport across the FAE, but not the VE, suggests that a specific integrin interaction was the dominating mechanism for improved nanoparticle uptake across the FAE., whereas charge interaction contributed substantially to the improved VE uptake. Copyright © 2006 by The American Society for Pharmacology and Experimental Therapeutics.

  • 14.
    Hagbom, Marie
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Meira de Faria, Felipe
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Tinnerfelt Winberg, Martin
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Westerberg, Sonja
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Keita, Åsa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Loitto, Vesa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Neurotrophic Factors Protect the Intestinal Barrier from Rotavirus Insult in Mice2020In: mBio, ISSN 2161-2129, E-ISSN 2150-7511, Vol. 11, no 1, article id e02834-19Article in journal (Refereed)
    Abstract [en]

    Increased intestinal permeability has been proposed as a mechanism of rotavirus-induced diarrhea. Studies with humans and mice have, however, shown that rotavirus leaves intestinal permeability unaffected or even reduced during diarrhea, in contrast to most bacterial infections. Gastrointestinal permeability is regulated by the vagus nerve and the enteric nervous system, which is composed of neurons and enteric glial cells (EGCs). We investigated whether the vagus nerve, serotonin (5-HT), EGCs, and neurotropic factors contribute to maintaining gut barrier homeostasis during rotavirus infection. Using subdiaphragmatic vagotomized and 5-HT3 receptor knockout mice, we found that the unaffected epithelial barrier during rotavirus infection is independent of the vagus nerve but dependent on 5-HT signaling through enteric intrinsic 5-HT3 receptors. Immunofluorescence analysis showed that rotavirus-infected enterocytes were in close contact with EGCs and enteric neurons and that the glial cell-derived neurotrophic factor (GDNF) was strongly upregulated in enterocytes of infected mice. Moreover, rotavirus and 5-HT activated EGCs (P &lt; 0.001). Using Ussing chambers, we found that GDNF and S-nitrosoglutathione (GSNO) led to denser epithelial barriers in small intestinal resections from noninfected mice (P &lt; 0.01) and humans (P &lt; 0.001) and that permeability was unaffected in rotavirus-infected mice. GSNO made the epithelial barrier denser in Caco-2 cells by increasing the expression of the tight junction protein zona occludens 1 (P &lt; 0.001), resulting in reduced passage of fluorescein isothiocyanate dextran (P &lt; 0.05) in rotavirus-infected monolayers. This is the first report to show that neurotropic factors contribute to maintaining the gut epithelial barrier during viral insult. IMPORTANCE Human and mouse studies have shown that rotavirus infection is associated with low inflammation and unaffected intestinal barrier at the time of diarrhea, properties different from most bacterial and inflammatory diseases of the gut. We showed by in vitro, ex vivo, and in vivo experiments that neurotrophic factors and 5-HT have barrier protective properties during rotavirus insult. These observations advance our understanding of how the gut barrier is protected against rotavirus and suggest that rotavirus affects the gut barrier differently from bacteria. This is the first report to show that neurotrophic factors contribute to maintain the gut epithelial barrier during viral insult.

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  • 15.
    Keita, Asa V.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Stertman, Linda
    Uppsala University.
    Sun, Yi-Qian
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Larhed, Agneta
    Uppsala University.
    Sjoholm, Ingvar
    Uppsala University.
    Söderholm, Johan D
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery . Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Effects of chronic stress on the immune response to oral human serum albumin-conjugated starch microparticles in rats2007In: Journal of Neuroimmunology, ISSN 0165-5728, E-ISSN 1872-8421, Vol. 183, no 01-Feb, p. 33-42Article in journal (Refereed)
    Abstract [en]

    Uptake of antigens and bacteria over the follicle-associated epithelium (FAE) is increased after chronic psychological stress. We investigated whether stress affects the immune response to particle-conjugated antigens taken up via the FAE. Rats were submitted to two 10-day periods of water avoidance stress and orally immunized during these periods. Stressed immunized rats displayed altered cell populations and a Th1-skewed immune response within the lymphoid follicles, together with enhanced delayed-type hypersensitivity. We conclude that chronic stress affects the cell-mediated immune response after oral immunization, which may have implications for the understanding of allergic and autoimmune diseases and development of oral vaccines. (c) 2006 Elsevier B.V. All rights reserved.

  • 16. Order onlineBuy this publication >>
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Barrier function of the Follicle-Associated Epithelium in Stress and Crohn's disease2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The earliest observable signs of Crohn’s disease are microscopic erosions in the follicle-associated epithelium (FAE) covering the Peyer’s patches. The FAE, which contains M cells, is specialised in sampling of luminal content and delivery to underlying immune cells. This sampling is crucial for induction of protective immune responses, but it also provides a route of entry for microorganisms into the mucosa. Crohn’s disease is associated with an increased immune response to bacteria, and the disease course can be altered by stress.

    The overall aim of this thesis was to study the effects of stress on the FAE and elucidate the role of FAE in the development of intestinal inflammation, specifically Crohn’s disease.

    Initially, rats were submitted to acute and chronic water avoidance stress to study the effects of psychological stress on the FAE. Stressed rats showed enhanced antigen and bacterial passage, and the passage was higher in FAE than in regular villus epithelium (VE). Further, stress gave rise to ultrastructural changes. Subsequent experiments revealed the stress-induced increase in permeability to be regulated by corticotropin-releasing hormone and mast cells. Furthermore, vasoactive intestinal peptide (VIP) mimicked the stress effects on permeability, and the VIP effects were inhibited by a mast cell stabiliser.

    Human studies of ileal mucosa from patients with non-inflammatory disease and healthy controls showed a higher antigen and bacterial passage in FAE than in VE. In patients with Crohn’s disease, the bacterial passage across the FAE was significantly increased compared to non-inflammatory and inflammatory controls (ulcerative colitis). Furthermore, there was an enhanced uptake of bacteria into dendritic cells, and augmented TNF-α release in Crohn’s disease mucosa.

    Taken together this thesis shows that stress can modulate the uptake of luminal antigens and bacteria via the FAE, through mechanisms involving CRH and mast cells. It further shows that human ileal FAE is functionally distinct from VE, and that Crohn’s disease patients exhibit enhanced FAE permeability compared to inflammatory and non-inflammatory controls.

    This thesis presents novel insights into regulation of the FAE barrier, as well as into the pathophysiology of Crohn’s disease by demonstrating a previously unrecognised defect of the FAE barrier function in ileal Crohn’s disease.

    List of papers
    1. Increased antigen and bacterial uptake in follicle-associated epithelium induced by chronic psychological stress in rats
    Open this publication in new window or tab >>Increased antigen and bacterial uptake in follicle-associated epithelium induced by chronic psychological stress in rats
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    2004 (English)In: Gut, ISSN 0017-5749, Vol. 53, no 4, p. 494-500Article in journal (Refereed) Published
    Abstract [en]

    Background: Chronic stress affects the course of inflammatory bowel disease and experimental colitis, and may also initiate intestinal inflammation in rats.

    Aim: To investigate the effects of stress on the M cell containing follicle associated epithelium, specialised in antigen uptake.

    Subjects and methods: Wistar rats were submitted to acute water avoidance stress for one hour or chronic water avoidance stress for 1 hour/day for 10 consecutive days. Permeability to 51Cr-EDTA, horseradish peroxidase, and chemically killed Escherichia coli K-12 was studied in both villus and follicle associated epithelium in Ussing chambers. Segments were further examined by light, electron, and confocal microscopy.

    Results: Acute stress increased horseradish peroxidase flux in villus as well as in follicle associated epithelium. Chronic stress further increased permeability to horseradish peroxidase in villus and follicle associated epithelium, in the latter by almost fourfold. Moreover, chronic stress induced over 30 times increased E coli passage in follicle associated epithelium whereas there was no significant increase in villus epithelium. Bacterial uptake was confirmed by confocal microscopy showing fluorescent bacteria penetrating and passing through the epithelial surface.

    Conclusions: These results show that the barrier function of follicle associated epithelium can be modulated, and that chronic stress enhances the uptake of luminal antigens and bacteria via the follicle associated epithelium. This can increase antigen exposure in Peyer’s patches thereby having implications in the initiation of proinflammatory immune responses within the intestinal mucosa.

    Keywords
    follicle associated epithelium, M cell, Peyer’s patch, inflammatory bowel disease, stress
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14562 (URN)10.1136/gut.2003.028506 (DOI)
    Available from: 2007-07-03 Created: 2007-07-03 Last updated: 2009-08-21
    2. Characterization of antigen and bacterial transport in the follicle-associated epithelium of human ileum
    Open this publication in new window or tab >>Characterization of antigen and bacterial transport in the follicle-associated epithelium of human ileum
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    2006 (English)In: Laboratory investigation, ISSN 0023-6837, Vol. 86, no 5, p. 504-516Article in journal (Refereed) Published
    Abstract [en]

    The follicle-associated epithelium (FAE), covering Peyer's patches, provides a route of entry for antigens and microorganisms. Animal studies showed enhanced antigen and bacterial uptake in FAE, but no study on barrier function of human FAE has been reported. Our aim was to characterize the normal barrier properties of human FAE. Specimens of normal ileum were taken from 30 patients with noninflammatory colonic disease. Villus epithelium (VE) and FAE were identified and mounted in Ussing chambers. Permeability to 51Cr-EDTA, transmucosal flux of the protein antigen, horseradish peroxidase (HRP), and transport of fluorescent Escherichia coli (chemically killed K-12 and live HB101) were measured. Uptake mechanisms were studied by confocal- and transmission electron microscopy, and by using pharmacological inhibitors in an in vitro coculture model of FAE and in human ileal FAE. HRP flux was substantially higher in FAE than in VE, and was reduced by an amiloride analog. Electron microscopy showed HRP-containing endosomes. Transport of E. coli K-12 and HB101 was also augmented in FAE and was confirmed by confocal microscopy. In vitro coculture experiments and electron microscopy revealed actin-dependent, mainly transcellular, uptake of E. coli K-12 into FAE. 51Cr-EDTA permeability was equal in FAE and VE. Augmented HRP flux and bacterial uptake but similar paracellular permeability, suggest functional variations of transcellular transport in the FAE. We show for the first time that FAE of human ileum is functionally distinct from regular VE, rendering the FAE more prone to bacterial–epithelial cell interactions and delivery of antigens to the mucosal immune system.

    Keywords
    E. coli, horseradish peroxidase, M cell, permeability, Peyer's patches
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14563 (URN)10.1038/labinvest.3700397 (DOI)
    Available from: 2007-07-03 Created: 2007-07-03
    3. Increased uptake of non-pathogenic E. coli via the follicle-associated epithelium in ileal Crohn’s disease
    Open this publication in new window or tab >>Increased uptake of non-pathogenic E. coli via the follicle-associated epithelium in ileal Crohn’s disease
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    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-14564 (URN)
    Available from: 2007-07-03 Created: 2007-07-03 Last updated: 2010-01-13
    4. Stress-induced barrier disruption of the follicle-associated epithelium involves corticotropin-releasing hormone, vasoactive intestinal peptide and mast cells
    Open this publication in new window or tab >>Stress-induced barrier disruption of the follicle-associated epithelium involves corticotropin-releasing hormone, vasoactive intestinal peptide and mast cells
    2010 (English)In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, Vol. 22, no 7, p. 770-e222Article in journal (Refereed) Published
    Abstract [en]

    Background The follicle-associated epithelium (FAE) is specialized in uptake and sampling of luminal antigens and bacteria. We previously showed that stress increased FAE permeability in rats. An increased uptake may alter antigen exposure in Peyers patches leading to intestinal disease. The aim of this study was to elucidate mechanisms involved in the acute stress-induced increase in FAE permeability. Methods Rats were pretreated i.p. with corticotropin-releasing hormone receptor (CRH-R) antagonist, neurokinin receptor 1 (NK-1R) antagonist, atropine, the mast cell stabilizer doxantrazole (DOX), or NaCl, and submitted to 1-h acute water avoidance stress. FAE tissues were mounted in Ussing chambers for measurements of permeability to 51Cr-EDTA, horseradish peroxidase (HRP) and chemically killed Escherichia coli K-12. Further, FAE segments were exposed in vitro in chambers to CRH, substance P (SP), carbachol, and DOX. Neurotransmitter- and receptor distribution was studied by immunohistochemistry. Key Results Stress-induced increases in uptake across FAE of HRP and E. coli were reduced by DOX, CRH-R antagonist and atropine, whereas the NK-1R antagonist decreased 51Cr-EDTA permeability. Exposure to CRH and carbachol increased HRP and E. coli passage, whereas SP increased bacterial and 51Cr-EDTA permeability. DOX counteracted all of these effects. Immunohistochemistry revealed CRH, acetylcholine, SP, and their receptors on mast cells within the Peyers patches, subepithelial dome, and adjacent villi. Conclusions & Inferences Corticotropin-releasing hormone and acetylcholine signaling affect mainly transcellular permeability while SP seems more selective toward the paracellular pathways. Our findings may be of importance for the understanding of the pathogenesis of stress-related intestinal disorders.

    Keywords
    inflammatory bowel disease; neurotrans-mitter; permeability; Peyers patches; Ussing chamber
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14565 (URN)10.1111/j.1365-2982.2010.01471.x (DOI)000278525200009 ()
    Available from: 2007-07-03 Created: 2007-07-03 Last updated: 2017-12-13
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  • 17.
    Keita, Åsa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Carlsson, A H.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Cigehn, M
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Ericson, Ann-Charlott
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Mckay, D M:
    University of Calgary, Canada .
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Vasoactive intestinal polypeptide regulates barrier function via mast cells in human intestinal follicle-associated epithelium and during stress in rats2013In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, Vol. 25, no 6, p. e406-e417Article in journal (Refereed)
    Abstract [en]

    Background Vasoactive intestinal polypeptide (VIP) has been implicated as a regulator of intestinal barrier function and inflammation. Our aim was to elucidate the role of VIP in follicle-associated epithelium (FAE) and villus epithelium (VE) permeability following stress in rats and on human intestinal barrier function. Methods Rats were injected intraperitoneally (i.p.) with VIP receptor-antagonists (anti-VPACs), a mast cell stabilizer, doxantrazole (DOX), or NaCl, and submitted to acute water avoidance stress. Ileal segments were mounted in Ussing chambers to assess 51chromium-edta (51Cr-edta) and Escherichia (E.) coli (strain K-12) permeability. Rat ileal and human ileal and colonic segments were exposed to VIP +/- anti-VPACs or DOX. An in vitro co-culture model of human FAE was used to study epithelial-VIP effects. VIP/VPACs distribution was assessed by microscopy. Key Results Stress increased 51Cr-edta and E.coli permeability in VE and FAE. The increases were abolished by i.p. injection of DOX or anti-VPACs. Ileal VIP-exposure ex vivo increased bacterial passage and this was reduced by DOX. In human FAE ex vivo, VIP treatment doubled bacterial uptake, which was normalized by DOX or anti-VPACs. No barrier effects were observed in human colonic tissue. VPACs were found in rat and human ileal follicles, with partial mast cell co-localization. The co-culture model confirmed VIPmast cellepithelial interactions in the regulation of barrier function. Conclusions andamp; Inferences Stress affects the FAE barrier by mechanisms involving VIP and VPACs on mucosal mast cells. We suggest a regulatory role for VIP in the control of ileal permeability that may be relevant to bacterialepithelial interactions in stress-related intestinal disorders.

  • 18.
    Keita, Åsa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Lindqvist, Carl Mårten
    Örebro University, Örebro, Sweden .
    Ost, Ake
    Aleris Medilab, Sweden.
    Ley Magana, Carlos Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Schoultz, Ida
    Örebro University, Örebro, Sweden .
    Halfvarson, Jonas
    Örebro University, Örebro, Sweden .
    Gut Barrier Dysfunction-A Primary Defect in Twins with Crohns Disease Predominantly Caused by Genetic Predisposition2018In: Journal of Crohn's & Colitis, ISSN 1873-9946, E-ISSN 1876-4479, Vol. 12, no 10, p. 1200-1209Article in journal (Refereed)
    Abstract [en]

    Background and Aims: The aetiology of Crohns disease is poorly understood. By investigating twin pairs discordant for Crohns disease, we aimed to assess whether the dysregulated barrier represents a cause or a consequence of inflammation and to evaluate the impact of genetic predisposition on barrier function. Methods: Ileal biopsies from 15 twin pairs discordant for Crohns disease [monozygotic n = 9, dizygotic n = 6] and 10 external controls were mounted in Ussing chambers to assess paracellular permeability to (51)Chromium [Cr]-EDTA and trancellular passage to non-pathogenic E. coli K-12. Experiments were performed with and without provocation with acetylsalicylic acid. Immunofluorescence and ELISA were used to quantify the expression level of tight junction proteins. Results: Healthy co-twins and affected twins displayed increased Cr-51-EDTA permeability at 120 min, both with acetylsalicylic acid [p amp;lt; 0.001] and without [p amp;lt; 0.001] when compared with controls. A significant increase in Cr-51-EDTA flux was already seen at 20 min in healthy monozygotic co-twins compared with controls [p amp;lt;= 0.05] when stratified by zygosity, but not in healthy dizygotic co-twins. No difference in E. coli passage was observed between groups. Immunofluorescence of the tight junction proteins claudin-5 and tricellulin showed lower levels in healthy co-twins [p amp;lt; 0.05] and affected twins [p amp;lt; 0.05] compared with external controls, while ELISA only showed lower tricellulin in Crohns disease twins [p amp;lt; 0.05]. Conclusion: Our results suggest that barrier dysfunction is a primary defect in Crohns disease, since changes were predominantly seen in healthy monozygotic co-twins. Passage of E. coli seems to be a consequence of inflammation, rather than representing a primary defect.

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  • 19.
    Keita, Åsa
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine.
    Salim, Sa´ad
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Jiang, T.
    Department of Clinical and Experimental Medicine Linköping University.
    Yang, P-C
    Intestinal Disease Research Program McMaster University, Hamilton, Canada.
    Franzén, Lennart
    Aleris Medilab Täby.
    Söderkvist, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Cell Biology.
    Magnusson, Karl-Eric
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology .
    Söderholm, Johan D
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery . Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Increased uptake of non-pathogenic E. coli via the follicle-associated epithelium in longstanding ileal Crohn's disease2008In: Journal of Pathology, ISSN 0022-3417, E-ISSN 1096-9896, Vol. 215, no 2, p. 135-144Article in journal (Refereed)
    Abstract [en]

    In Crohn's disease (CD), inflammation is driven by luminal commensal micro-organisms, however, mechanisms of early phases of inflammation need further clarification. The earliest observable lesions of recurrent CD are microscopic erosions at the specialized follicle-associated epithelium (FAE), which lines the Peyer's patches. Therefore, our aim was to investigate the mucosal barrier to non-pathogenic bacteria in FAE of CD. The FAE of macroscopically normal ileum from patients with longstanding CD, ulcerative colitis, and controls was studied in Ussing chambers regarding electrophysiology and permeability to 51Cr-EDTA, horseradish peroxidase, and non-pathogenic E. coli strains. Transepithelial passage routes and uptake into dendritic cells were studied by confocal and electron microscopy. FAE of CD showed increased numbers of adherent bacteria, after E. coli exposure in Ussing chambers, as well as spontaneously in non-exposed archival surgical tissues. Further, we found increased uptake of fluorescent E. coli K-12 and HB101 across FAE of CD, but not in ulcerative colitis. Microscopy demonstrated intercellular and transcellular uptake of E. coli in CD, but only transcellular in controls. FAE exposed to E. coli demonstrated changes in conductance and 51Cr-EDTA permeability, suggesting that bacteria affected the paracellular pathway in CD mucosa. Following bacterial uptake, CD mucosa also demonstrated an increased percentage of E. coli co-localizing with dendritic cells, and augmented tissue release of TNF-α. Our data present novel insights into the pathophysiology of CD by demonstrating a previously unrecognized defect of FAE barrier to bacteria in ileal CD, leading to increased load of commensal bacteria to the inductive sites of mucosal immunity. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  • 20.
    Keita, Åsa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Mucosal permeability and mast cells as targets for functional gastrointestinal disorders2018In: Current opinion in pharmacology (Print), ISSN 1471-4892, E-ISSN 1471-4973, Vol. 43, p. 66-71Article, review/survey (Refereed)
    Abstract [en]

    The intestinal mucosa is constantly exposed to harmful lumina! content, and uptake is closely controlled and regulated by neuro-immune factors. If control is broken, it might lead to ongoing enhanced mucosal permeability, potentially resulting in functional gastrointestinal disorders. The importance of mast cells in the regulation of the mucosal barrier has become obvious, and increased numbers and more activated mast cells have been observed in irritable bowel syndrome, functional dyspepsia and gastroesophageal reflux disease. To target the disturbed mucosal permeability, directly or via mast cells, is therefore currently of major interest. For example, administration of mast cell stabilizers and probiotics have shown promising effects in patients with functional gastrointestinal disorders.

  • 21.
    Keita, Åsa V
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Gullberg, Elisabet
    Department of Pharmacy, Uppsala University, BMC, Uppsala, Sweden.
    Ericson, Ann-Charlott
    Linköping University, Department of Clinical and Experimental Medicine, Cellbiology. Linköping University, Faculty of Health Sciences.
    Salim, Sa’ad Y
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Wallon, Conny
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Kald, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Artursson, Per
    Department of Pharmacy, Uppsala University, BMC, Uppsala, Sweden.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Characterization of antigen and bacterial transport in the follicle-associated epithelium of human ileum2006In: Laboratory investigation, ISSN 0023-6837, Vol. 86, no 5, p. 504-516Article in journal (Refereed)
    Abstract [en]

    The follicle-associated epithelium (FAE), covering Peyer's patches, provides a route of entry for antigens and microorganisms. Animal studies showed enhanced antigen and bacterial uptake in FAE, but no study on barrier function of human FAE has been reported. Our aim was to characterize the normal barrier properties of human FAE. Specimens of normal ileum were taken from 30 patients with noninflammatory colonic disease. Villus epithelium (VE) and FAE were identified and mounted in Ussing chambers. Permeability to 51Cr-EDTA, transmucosal flux of the protein antigen, horseradish peroxidase (HRP), and transport of fluorescent Escherichia coli (chemically killed K-12 and live HB101) were measured. Uptake mechanisms were studied by confocal- and transmission electron microscopy, and by using pharmacological inhibitors in an in vitro coculture model of FAE and in human ileal FAE. HRP flux was substantially higher in FAE than in VE, and was reduced by an amiloride analog. Electron microscopy showed HRP-containing endosomes. Transport of E. coli K-12 and HB101 was also augmented in FAE and was confirmed by confocal microscopy. In vitro coculture experiments and electron microscopy revealed actin-dependent, mainly transcellular, uptake of E. coli K-12 into FAE. 51Cr-EDTA permeability was equal in FAE and VE. Augmented HRP flux and bacterial uptake but similar paracellular permeability, suggest functional variations of transcellular transport in the FAE. We show for the first time that FAE of human ileum is functionally distinct from regular VE, rendering the FAE more prone to bacterial–epithelial cell interactions and delivery of antigens to the mucosal immune system.

  • 22.
    Keita, Åsa V.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery UHL.
    Barrier dysfunction and bacterial uptake in the follicle-associated epithelium of ileal Crohns disease2012In: Annals of the New York Academy of Sciences, ISSN 0077-8923, E-ISSN 1749-6632, Vol. 1258, no 1, p. 125-134Article in journal (Refereed)
    Abstract [en]

    The ability to control uptake across the mucosa and protect from harmful substances in the gut lumen is defined as intestinal barrier function. The etiology of Crohns disease is unknown, but genetic, environmental, and immunological factors all contribute. The frontline between these factors lies in the intestinal barrier. The most important inflammation-driving environmental factor in Crohns disease is the microbiota, where Esherichia coli strains have been assigned a key role. The first observable signs of Crohns disease are small aphtoid ulcers over Peyers patches and lymphoid follicles. The overlaying follicle-associated epithelium (FAE) is specialized for luminal sampling and is an entry site for antigens and bacteria. We have demonstrated increased E. coli uptake across the FAE in Crohns disease, which may initiate inflammation. This short review will discuss barrier dysfunction and bacteria in the context of ileal Crohns disease, and how the FAE might be the site of initial inflammation.

  • 23.
    Keita, Åsa V.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    The intestinal barrier and its regulation by neuroimmune factors2010In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, Vol. 22, no 7, p. 718-733Article, review/survey (Refereed)
    Abstract [en]

    Background The ability to control uptake across the mucosa and protect from damage of harmful substances from the lumen is defined as intestinal barrier function. A disturbed barrier dysfunction has been described in many human diseases and animal models, for example, inflammatory bowel disease, irritable bowel syndrome, and intestinal hypersensitivity. In most diseases and models, alterations are seen both of the paracellular pathway, via the tight junctions, and of the transcellular routes, via different types of endocytosis. Recent studies of pathogenic mechanisms have demonstrated the important role of neuroimmune interaction with the epithelial cells in the regulation of barrier function. Neural impulses from extrinsic vagal and/or sympathetic efferent fibers or intrinsic enteric nerves influence mucosal barrier function via direct effects on epithelial cells or via interaction with immune cells. For example, by nerve-mediated activation by corticotropin-releasing hormone or cholinergic pathways, mucosal mast cells release a range of mediators with effects on transcellular, and/or paracellular permeability (for example, tryptase, TNF-alpha, nerve growth factor, and interleukins). Purpose In this review, we discuss current physiological and pathophysiological aspects of the intestinal barrier and, in particular, its regulation by neuroimmune factors.

  • 24.
    Keita, Åsa V
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Surgery UHL.
    Ericson, Ann-Charlott
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Stress-induced barrier disruption of the follicle-associated epithelium involves corticotropin-releasing hormone, vasoactive intestinal peptide and mast cells2010In: Neurogastroenterology and Motility, ISSN 1350-1925, E-ISSN 1365-2982, Vol. 22, no 7, p. 770-e222Article in journal (Refereed)
    Abstract [en]

    Background The follicle-associated epithelium (FAE) is specialized in uptake and sampling of luminal antigens and bacteria. We previously showed that stress increased FAE permeability in rats. An increased uptake may alter antigen exposure in Peyers patches leading to intestinal disease. The aim of this study was to elucidate mechanisms involved in the acute stress-induced increase in FAE permeability. Methods Rats were pretreated i.p. with corticotropin-releasing hormone receptor (CRH-R) antagonist, neurokinin receptor 1 (NK-1R) antagonist, atropine, the mast cell stabilizer doxantrazole (DOX), or NaCl, and submitted to 1-h acute water avoidance stress. FAE tissues were mounted in Ussing chambers for measurements of permeability to 51Cr-EDTA, horseradish peroxidase (HRP) and chemically killed Escherichia coli K-12. Further, FAE segments were exposed in vitro in chambers to CRH, substance P (SP), carbachol, and DOX. Neurotransmitter- and receptor distribution was studied by immunohistochemistry. Key Results Stress-induced increases in uptake across FAE of HRP and E. coli were reduced by DOX, CRH-R antagonist and atropine, whereas the NK-1R antagonist decreased 51Cr-EDTA permeability. Exposure to CRH and carbachol increased HRP and E. coli passage, whereas SP increased bacterial and 51Cr-EDTA permeability. DOX counteracted all of these effects. Immunohistochemistry revealed CRH, acetylcholine, SP, and their receptors on mast cells within the Peyers patches, subepithelial dome, and adjacent villi. Conclusions & Inferences Corticotropin-releasing hormone and acetylcholine signaling affect mainly transcellular permeability while SP seems more selective toward the paracellular pathways. Our findings may be of importance for the understanding of the pathogenesis of stress-related intestinal disorders.

  • 25.
    Keita, Åsa
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Yakimenko Alkaissi, Lina
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Boström Holm, Elin
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Heil, Stéphanie
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Chassaing, Benoit
    Georgia State Univ, GA 30303 USA; Georgia State Univ, GA 30303 USA.
    Darfeuille-Michaud, Arlette
    Univ Auvergne, France.
    McKay, Derek M.
    Univ Calgary, Canada.
    Söderholm, Johan D
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Enhanced E. coli LF82 Translocation through the Follicle-associated Epithelium in Crohns Disease is Dependent on Long Polar Fimbriae and CEACAM6 expression, and Increases Paracellular Permeability2020In: Journal of Crohn's & Colitis, ISSN 1873-9946, E-ISSN 1876-4479, Vol. 14, no 2, p. 216-229Article in journal (Refereed)
    Abstract [en]

    Background and Aims: Patients with Crohns disease [CD] harbour an increased number of adherent-invasive E. coli [AIEC]. The strain LF82, identified in the ileal mucosa of CD patients, has been extensively studied for pathogenic mechanisms. However, understanding of the interaction of LF82 with the intestinal mucosa of CD patients is lacking. Methods: Here, we investigated the importance of long polar fimbriae [LPF] type 1 pili and the carcinoembryonic antigen-related cell-adhesion molecule 6 [CEACAM6] for translocation of LF82 in an in vitro model of follicle-associated epithelium [FAE], and in the FAE and villus epithelium [VE] of patients with CD and controls, using Ussing chambers. Results: Significantly greater LF82 passage occurred in the FAE model compared with in the VE Caco-2cl1 mono-culture. Moreover, bacterial translocation was inhibited by either LPF disruption or pre-incubation with anti-CEACAM6 antibody. Tissue mounted in Ussing chambers showed significantly higher LF82 passage in FAE from patients with CD compared with control FAE, that was diminished in LF82 lacking LPF and by blocking host CEACAM6. Interestingly, addition of LF82 to the CD FAE tissues significantly increased paracellular permeability [of (51)Chromium-EDTA] compared with baseline, and the increase was inhibited by anti-CEACAM6. Immunofluorescence and immunoblots showed higher expression of CEACAM6 in FAE of patients with CD compared with in FAE from controls. Conclusions: These data suggest that the FAE of CD patients is a site of vulnerability for invasion by LF82 via a mechanism that requires both bacterial LPF and host CEACAM6. Further, LF82 has the ability to increase paracellular passage through the FAE of patients with CD. These data can help define novel therapeutic targets in CD for the prevention of clinical recurrence.

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  • 26.
    Lopes, Fernando
    et al.
    Univ Calgary, Canada.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Saxena, Alpana
    Univ Calgary, Canada.
    Reyes, Jose Luis
    Univ Calgary, Canada.
    Mancini, Nicole L.
    Univ Calgary, Canada.
    Al Rajabi, Ala
    Univ Calgary, Canada.
    Wang, Arthur
    Univ Calgary, Canada.
    Baggio, Cristiane H.
    Univ Calgary, Canada.
    Dicay, Michael
    Univ Calgary, Canada.
    van Dalen, Rob
    Univ Toronto, Canada.
    Ahn, Younghee
    Univ Calgary, Canada.
    Carneiro, Matheus B. H.
    Univ Calgary, Canada.
    Peters, Nathan C.
    Univ Calgary, Canada.
    Rho, Jong M.
    Univ Calgary, Canada.
    MacNaughton, Wallace K.
    Univ Calgary, Canada.
    Girardin, Stephen E.
    Univ Toronto, Canada.
    Jijon, Humberto
    Univ Calgary, Canada.
    Philpott, Dana J.
    Univ Toronto, Canada.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    McKay, Derek M.
    Univ Calgary, Canada.
    ER-stress mobilization of death-associated protein kinase-1-dependent xenophagy counteracts mitochondria stress-induced epithelial barrier dysfunction2018In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 293, no 9, p. 3073-3087Article in journal (Refereed)
    Abstract [en]

    The gut microbiome contributes to inflammatory bowel disease (IBD), in which bacteria can be present within the epithelium. Epithelial barrier function is decreased in IBD, and dysfunctional epithelial mitochondria and endoplasmic reticulum (ER) stress have been individually associated with IBD. We therefore hypothesized that the combination of ER and mitochondrial stresses significantly disrupt epithelial barrier function. Here, we treated human colonic biopsies, epithelial colonoids, and epithelial cells with an uncoupler of oxidative phosphorylation, dinitrophenol (DNP), with or without the ER stressor tunicamycin and assessed epithelial barrier function by monitoring internalization and translocation of commensal bacteria. We also examined barrier function and colitis in mice exposed to dextran sodium sulfate (DSS) or DNP and co-treated with DAPK6, an inhibitor of death-associated protein kinase 1 (DAPK1). Contrary to our hypothesis, induction of ER stress (i.e. the unfolded protein response) protected against decreased barrier function caused by the disruption of mitochondrial function. ER stress did not prevent DNP-driven uptake of bacteria; rather, specific mobilization of the ATF6 arm of ER stress and recruitment of DAP K1 resulted in enhanced autophagic killing (xenophagy) of bacteria. Of note, epithelia with a Crohns disease susceptibility mutation in the autophagy gene ATG16L.1 exhibited less xenophagy. Systemic delivery of the DAPK1 inhibitor DAPK6 increased bacterial translocation in DSS- or DNP-treated mice. We conclude that promoting ER stress ATF6 DAPK1 signaling in transporting enterocytes counters the transcellular passage of bacteria evoked by dysfunctional mitochondria, thereby reducing the potential for metabolic stress to reactivate or perpetuate inflammation.

  • 27.
    Mall, J. P. Ganda
    et al.
    Orebro Univ, Sweden; Orebro Univ, Sweden.
    Lofvendahl, L.
    Orebro Univ, Sweden.
    Lindqvist, C. M.
    Orebro Univ, Sweden.
    Brummer, R. J.
    Orebro Univ, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Schoultz, I.
    Orebro Univ, Sweden; Orebro Univ, Sweden.
    Differential effects of dietary fibres on colonic barrier function in elderly individuals with gastrointestinal symptoms2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 13404Article in journal (Refereed)
    Abstract [en]

    Gastrointestinal problems are common in elderly and often associated with psychological distress and increased levels of corticotrophin-releasing hormone, a hormone known to cause mast cell (MC) degranulation and perturbed intestinal barrier function. We investigated if dietary fibres (non-digestible polysaccharides [NPS]) could attenuate MC-induced colonic hyperpermeability in elderly with gastrointestinal (GI) symptoms. Colonic biopsies from elderly with diarrhoea and/or constipation (n = 18) and healthy controls (n = 19) were mounted in Ussing chambers and pre-stimulated with a yeast-derived beta (beta)-glucan (0.5 mg/ml) or wheat-derived arabinoxylan (0.1 mg/ml) before the addition of the MC-degranulator Compound (C) 48/80 (10 ng/ml). Permeability markers were compared pre and post exposure to C48/80 in both groups and revealed higher baseline permeability in elderly with GI symptoms. beta-glucan significantly attenuated C48/80-induced hyperpermeability in elderly with GI symptoms but not in healthy controls. Arabinoxylan reduced MC-induced paracellular and transcellular hyperpermeability across the colonic mucosa of healthy controls, but did only attenuate transcellular permeability in elderly with GI symptoms. Our novel findings indicate that NPS affect the intestinal barrier differently depending on the presence of GI symptoms and could be important in the treatment of moderate constipation and/or diarrhoea in elderly.

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  • 28.
    Mall, John-Peter Ganda
    et al.
    Orebro Univ, Sweden; Orebro Univ, Sweden.
    Ostlund-Lagerstrom, Lina
    Orebro Univ, Sweden; Orebro Univ, Sweden.
    Lindqvist, Carl Marten
    Orebro Univ, Sweden.
    Algilani, Samal
    Orebro Univ, Sweden.
    Rasoal, Dara
    Orebro Univ, Sweden.
    Repsilber, Dirk
    Orebro Univ, Sweden.
    Brummer, Robert J.
    Orebro Univ, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Schoultz, Ida
    Orebro Univ, Sweden.
    Are self-reported gastrointestinal symptoms among older adults associated with increased intestinal permeability and psychological distress?2018In: BMC Geriatrics, ISSN 1471-2318, E-ISSN 1471-2318, Vol. 18, article id 75Article in journal (Refereed)
    Abstract [en]

    Background: Despite the substantial number of older adults suffering from gastrointestinal (GI) symptoms little is known regarding the character of these complaints and whether they are associated with an altered intestinal barrier function and psychological distress. Our aim was to explore the relationship between self-reported gut health, intestinal permeability and psychological distress among older adults. Methods: Three study populations were included: 1) older adults with GI symptoms (n = 24), 2) a group of older adults representing the general elderly population in Sweden (n = 22) and 3) senior orienteering athletes as a potential model of healthy ageing (n = 27). Questionnaire data on gut-health, psychological distress and level of physical activity were collected. Intestinal permeability was measured by quantifying zonulin in plasma. The level of systemic and local inflammation was monitored by measuring C-reactive protein (CRP), hydrogen peroxide in plasma and calprotectin in stool samples. The relationship between biomarkers and questionnaire data in the different study populations was illustrated using a Principal Component Analysis (PCA). Results: Older adults with GI symptoms displayed significantly higher levels of both zonulin and psychological distress than both general older adults and senior orienteering athletes. The PCA analysis revealed a separation between senior orienteering athletes and older adults with GI symptoms and showed an association between GI symptoms, psychological distress and zonulin. Conclusions: Older adults with GI symptoms express increased plasma levels of zonulin, which might reflect an augmented intestinal permeability. In addition, this group suffer from higher psychological distress compared to general older adults and senior orienteering athletes. This relationship was further confirmed by a PCA plot, which illustrated an association between GI symptoms, psychological distress and intestinal permeability.

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  • 29.
    Parsons, Bryony N.
    et al.
    University of Liverpool, England .
    Wigley, Paul
    University of Liverpool, England .
    Simpson, Hannah L.
    University of Liverpool, England .
    Williams, Jonathan M.
    University of Liverpool, England .
    Humphrey, Suzie
    University of Liverpool, England .
    Salisbury, Anne-Marie
    University of Liverpool, England .
    Watson, Alastair J. M.
    University of Liverpool, England University of E Anglia, England .
    Fry, Stephen C.
    University of Edinburgh, Scotland .
    O'Brien, David
    Provexis Plc, Scotland .
    Roberts, Carol L.
    University of Liverpool, England Provexis Plc, Scotland .
    O'Kennedy, Niamh
    Provexis Plc, Scotland .
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Rhodes, Jonathan M.
    University of Liverpool, England .
    Campbell, Barry J.
    University of Liverpool, England .
    Dietary Supplementation with Soluble Plantain Non-Starch Polysaccharides Inhibits Intestinal Invasion of Salmonella Typhimurium in the Chicken2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 2, p. 87658-Article in journal (Refereed)
    Abstract [en]

    Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S. Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S. Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1-99.7; Pless than0.0001). In vitro studies confirmed that plantain NSP (5-10 mg/ml) inhibited adhesion of S. Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64-81); Pless than0.001) and to primary chick caecal crypts (82% mean inhibition (95% CI, 75-90); Pless than0.001). Adherence inhibition was shown to be mediated via an effect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis.

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  • 30.
    Roberts, Carol L
    et al.
    University of Liverpool.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Duncan, Sylvia H
    University of Aberdeen.
    O'Kennedy, Niamh
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Dabrosin Söderholm, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Rhodes, Jonathan M
    University of Liverpool.
    Campbell, Barry J
    University of Liverpool.
    Translocation of Crohns disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers2010In: GUT, ISSN 0017-5749, Vol. 59, no 10, p. 1331-1339Article in journal (Refereed)
    Abstract [en]

    Background Crohns disease is common in developed nations where the typical diet is low in fibre and high in processed food. Primary lesions overlie Peyers patches and colonic lymphoid follicles where bacterial invasion through M-cells occurs. We have assessed the effect of soluble non-starch polysaccharide (NSP) and food emulsifiers on translocation of Escherichia coli across M-cells. Methods To assess effects of soluble plant fibres and food emulsifiers on translocation of mucosa-associated E coli isolates from Crohns disease patients and from non-Crohns controls, we used M-cell monolayers, generated by co-culture of Caco2-cl1 and Raji B cells, and human Peyers patches mounted in Ussing chambers. Results E coli translocation increased across M-cells compared to parent Caco2-cl1 monocultures; 15.8-fold (IQR 6.2-32.0) for Crohns disease E coli (N=8) and 6.7-fold (IQR 3.7-21.0) for control isolates (N=5). Electronmicroscopy confirmed E coli within M-cells. Plantain and broccoli NSP markedly reduced E coli translocation across M-cells at 5 mg/ml (range 45.3-82.6% inhibition, pandlt;0.01); apple and leek NSP had no significant effect. Polysorbate-80, 0.01% vol/vol, increased E coli translocation through Caco2-cl1 monolayers 59-fold (pandlt;0.05) and, at higher concentrations, increased translocation across M-cells. Similarly, E coli translocation across human Peyers patches was reduced 45+/-7% by soluble plantain NSP (5 mg/ml) and increased 2-fold by polysorbate-80 (0.1% vol/vol). Conclusions Translocation of E coli across M-cells is reduced by soluble plant fibres, particularly plantain and broccoli, but increased by the emulsifier Polysorbate-80. These effects occur at relevant concentrations and may contribute to the impact of dietary factors on Crohns disease pathogenesis.

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  • 31. Roberts, Carol L.
    et al.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Parsons, Bryony N.
    University of Liverpool, England .
    Prorok-Hamon, Maelle
    University of Liverpool, England .
    Knight, Paul
    University of Liverpool, England .
    Winstanley, Craig
    University of Liverpool, England .
    O´Kennedy, Niamh
    Provexis Plc, Aberdeen, UK.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Rhodes, Jonathan M.
    University of Liverpool, England .
    Campbell, Barry J.
    University of Liverpool, England .
    Soluble plantain fibre blocks adhesion and M-cell translocation of intestinal pathogens2013In: Journal of Nutritional Biochemistry, ISSN 0955-2863, E-ISSN 1873-4847, Vol. 24, no 1, p. 97-103Article in journal (Refereed)
    Abstract [en]

    Dietary fibres may have prebiotic effects mediated by promotion of beneficial bacteria. This study explores the possibility that soluble plant fibre may also improve health by inhibiting epithelial adhesion and translocation by pathogenic bacteria. We have focussed on soluble non-starch polysaccharide (NSP) from plantain bananas (Musa spp.) which previous studies showed to be particularly effective at blocking Escherichia coli epithelial adherence. In vitro and ex vivo studies assessed the ability of plantain NSP to inhibit epithelial cell adhesion and invasion of various bacterial pathogens, and to inhibit their translocation through microfold (M)-cells and human Peyers patches mounted in Ussing chambers. Plantain NSP showed dose-related inhibition of epithelial adhesion and M-cell translocation by a range of pathogens. At 5 mg/ml, a concentration readily achievable in the gut lumen, plantain NSP inhibited adhesion to Caco2 cells by Salmonella Typhimurium (85.0 +/- 8.2%, Pandlt;.01), Shigella sonnei (46.6 +/- 29.3%. Pandlt;.01), enterotoxigenic E.coli (56.1 +/- 23.7%, Pandlt;.05) and Clostridium difficile (67.6 +/- 12.3%, Pandlt;.001), but did not inhibit adhesion by enteropathogenic E.coli. Plantain NSP also inhibited invasion of Caco2 cells by S. Typhimurium (80.2 +/- 9.7%) and Sh. sonnei (46.7 +/- 13.4%); Pandlt;.01. Plantain NSP, 5 mg/ml, also inhibited translocation of S. Typhimurium and Sh. sonnei across M-cells by 73.3 +/- 5.2% and 46.4 +/- 7.7% respectively (Pandlt;.05). Similarly, S. Typhimurium translocation across Peyers patches was reduced 65.9 +/- 8.1% by plantain NSP (Pandlt;.01). Soluble plantain fibre can block epithelial adhesion and M-cell translocation of intestinal pathogens. This represents an important novel mechanism by which soluble dietary fibres can promote intestinal health and prevent infective diarrhoea. Crown Copyright

  • 32.
    Salim, Sa'ad
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Silva, Manuel A
    McMaster University.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Larsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Andersson, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Perdue, Mary H
    McMaster University.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    CD83(+)CCR7(-) Dendritic Cells Accumulate in the Subepithelial Dome and Internalize Translocated Escherichia coli HB101 in the Peyers Patches of Heal Crohns Disease2009In: American Journal of Pathology, ISSN 0002-9440, E-ISSN 1525-2191, Vol. 174, no 1, p. 82-90Article in journal (Refereed)
    Abstract [en]

    Recurrent Crohns disease originates with small erosions in the follicle-associated epithelium overlying the Peyers patches. Animal studies have illustrated mucosal immune regulation by dendritic cells located in the subepithelial dome. The aim of this study was to characterize the dendritic cells at this specific site in patients with Crohns disease. Heal tissues were obtained after surgery performed on Crohns patients; ileal samples from noninflammatory bowel disease and ulcerative colitis served as standard and inflammatory controls, respectively. Flow cytometry of isolated intestinal mononuclear cells showed a larger subset of dendritic cells in Crohns samples compared with controls. This finding was corroborated by confocal microscopy, showing enhanced infiltrates of cells positive for the dendritic cell markers, DC-SIGN(+) and CD83(+), in the subepithelial dome. Moreover, the CD83(+) cells in Crohns tissues showed reduced expression of the lymph node migratory receptor, CCR7, possibly contributing to the high numbers of dendritic cells. After exposure to nonpathogenic Escherichia coli in Ussing chambers, dendritic cells in the subepithelial dome of Crohns disease demonstrated increased co-localization with translocated bacteria. Immunohistochemical results revealed that DC-SIGN(+) cells in Crohns tissues were found to express toll-like receptor 4 and produce tumor necrosis factor-a. In conclusion, nonmigrating dendritic cells that accumulate in the subepithelial dome and internalize nonpathogenic bacteria may be important for the onset and perpetuation of mucosal inflammation in Crohns disease.

  • 33.
    Schoultz, Ida
    et al.
    Orebro Univ, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Cellular and Molecular Therapeutic Targets in Inflammatory Bowel Disease-Focusing on Intestinal Barrier Function2019In: CELLS, Vol. 8, no 2, article id 193Article, review/survey (Refereed)
    Abstract [en]

    The human gut relies on several cellular and molecular mechanisms to allow for an intact and dynamical intestinal barrier. Normally, only small amounts of luminal content pass the mucosa, however, if the control is broken it can lead to enhanced passage, which might damage the mucosa, leading to pathological conditions, such as inflammatory bowel disease (IBD). It is well established that genetic, environmental, and immunological factors all contribute in the pathogenesis of IBD, and a disturbed intestinal barrier function has become a hallmark of the disease. Genetical studies support the involvement of intestinal barrier as several susceptibility genes for IBD encode proteins with key functions in gut barrier and homeostasis. IBD patients are associated with loss in bacterial diversity and shifts in the microbiota, with a possible link to local inflammation. Furthermore, alterations of immune cells and several neuro-immune signaling pathways in the lamina propria have been demonstrated. An inappropriate immune activation might lead to mucosal inflammation, with elevated secretion of pro-inflammatory cytokines that can affect the epithelium and promote a leakier barrier. This review will focus on the main cells and molecular mechanisms in IBD and how these can be targeted in order to improve intestinal barrier function and reduce inflammation.

  • 34.
    Shrestha, Neha
    et al.
    Catholic University of Louvain, Belgium.
    Bouttefeux, Oriane
    Catholic University of Louvain, Belgium.
    Vanvarenberg, Kevin
    Catholic University of Louvain, Belgium.
    Lundquist, Patrik
    Uppsala University, Sweden.
    Cunarro, Juan
    University of Santiago de Compostela, Spain.
    Tovar, Sulay
    University of Santiago de Compostela, Spain.
    Khodus, Georgiy
    Uppsala University, Sweden.
    Andersson, Ellen
    Vrinnevi Hospital, Sweden.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Gonzalez Dieguez, Carlos
    University of Santiago de Compostela, Spain.
    Artursson, Per
    Uppsala University, Sweden.
    Preat, Veronique
    Catholic University of Louvain, Belgium.
    Beloqui, Ana
    Catholic University of Louvain, Belgium.
    The stimulation of GLP-1 secretion and delivery of GLP-1 agonists &ITvia&IT nanostructured lipid carriers2018In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 10, no 2, p. 603-613Article in journal (Refereed)
    Abstract [en]

    Nanoparticulate based drug delivery systems have been extensively studied to efficiently encapsulate and deliver peptides orally. However, most of the existing data mainly focus on the nanoparticles as a drug carrier, but the ability of nanoparticles having a biological effect has not been exploited. Herein, we hypothesize that nanostructured lipid carriers (NLCs) could activate the endogenous glucagon-like peptide-1 (GLP-1) secretion and also act as oral delivery systems for GLP-1 analogs (exenatide and liraglutide). NLCs effectively encapsulated the peptides, the majority of which were only released under the intestinal conditions. NLCs, with and without peptide encapsulation, showed effective induction of GLP-1 secretion in vitro from the enteroendocrinal L-cells (GLUTag). NLCs also showed a 2.9-fold increase in the permeability of exenatide across the intestinal cell monolayer. The intestinal administration of the exenatide and liraglutide loaded NLCs did not demonstrate any glucose lowering effect on normal mice. Further, ex vivo studies depicted that the NLCs mainly adhered to the mucus layer. In conclusion, this study demonstrates that NLCs need further optimization to overcome the mucosal barrier in the intestine; nonetheless, this study also presents a promising strategy to use a dual-action drug delivery nanosystem which synergizes its own biological effect and that of the encapsulated drug molecule.

  • 35.
    Thomson, Amanda
    et al.
    Sch Med, Wales; Newcastle Univ, England.
    Smart, Kathryn
    Sch Med, Wales.
    Somerville, Michelle S.
    Sch Med, Wales.
    Lauder, Sarah N.
    Sch Med, Wales.
    Appanna, Gautham
    Sch Med, Wales; Univ Hosp Wales, Wales.
    Horwood, James
    Univ Hosp Wales, Wales.
    Raj, Lawrence Sunder
    Univ Hosp Wales, Wales.
    Srivastava, Brijesh
    Univ Hosp Wales, Wales.
    Durai, Dharmaraj
    Univ Hosp Wales, Wales.
    Scurr, Martin J.
    Sch Med, Wales.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Gallimore, Awen M.
    Sch Med, Wales.
    Godkin, Andrew
    Sch Med, Wales; Univ Hosp Wales, Wales.
    The Ussing chamber system for measuring intestinal permeability in health and disease2019In: BMC Gastroenterology, ISSN 1471-230X, E-ISSN 1471-230X, Vol. 19, article id 98Article in journal (Refereed)
    Abstract [en]

    BackgroundThe relationship between intestinal epithelial integrity and the development of intestinal disease is of increasing interest. A reduction in mucosal integrity has been associated with ulcerative colitis, Crohns disease and potentially could have links with colorectal cancer development. The Ussing chamber system can be utilised as a valuable tool for measuring gut integrity. Here we describe step-by-step methodology required to measure intestinal permeability of both mouse and human colonic tissue samples ex vivo, using the latest equipment and software. This system can be modified to accommodate other tissues.MethodsAn Ussing chamber was constructed and adapted to support both mouse and human tissue to measure intestinal permeability, using paracellular flux and electrical measurements. Two mouse models of intestinal inflammation (dextran sodium sulphate treatment and T regulatory cell depletion using C57BL/6-FoxP3(DTR) mice) were used to validate the system along with human colonic biopsy samples.ResultsDistinct regional differences in permeability were consistently identified within mouse and healthy human colon. In particular, mice showed increased permeability in the mid colonic region. In humans the left colon is more permeable than the right. Furthermore, inflammatory conditions induced chemically or due to autoimmunity reduced intestinal integrity, validating the use of the system.ConclusionsThe Ussing chamber has been used for many years to measure barrier function. However, a clear and informative methods paper describing the setup of modern equipment and step-by-step procedure to measure mouse and human intestinal permeability isnt available. The Ussing chamber system methodology we describe provides such detail to guide investigation of gut integrity.

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  • 36.
    Trulsson, Lena
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Velin, Åsa
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Herder, Anders
    Söderkvist, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Cell biology.
    Rüter, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Smeds, Staffan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Telomerase activity in surgical specimens and fine-needle aspiration biopsies from hyperplastic and neoplastic human thyroid tissues2003In: American Journal of Surgery, ISSN 0002-9610, E-ISSN 1879-1883, Vol. 186, no 1, p. 83-88Article in journal (Refereed)
    Abstract [en]

    Background: Telomerase activity (TA) indicates malignancy, but activated lymphocytes also express TA. Correlation between TA in thyroid tissues and fine-needle aspiration (FNA) samples and knowledge about TA in adjacent tissue are of importance. Methods: The telomeric repeat amplification protocol assay followed by enzyme-linked immunosorbent assay detection was performed on 78 thyroid cases including 53 suspected malignancies, preoperative and perioperative FNA specimens, and adjacent tissue. Results: Benign lesions in cancer-suspected cases were TA negative. Eight of 13 papillary (62%) and 4 of 5 follicular (80%) tumors were TA positive (TA+). Lower TA was observed in conventional papillary cancer than in follicular, tall cell variant of papillary and anaplastic cancers. Adjacent tissues with lymphocyte infiltration were TA+ in 9 of 17 cases (53%). Nine of 65 adjacent tissues (14%) were TA+. Three of 6 preoperative and 9 of 11 perioperative FNA samples from malignant tumors corresponded to the tissue TA. Conclusions: High TA may reflect more severe thyroid cancer. Telomerase activity in FNA biopsies does not add reliable diagnostic information, and presence of lymphocytes can give false-positive results.

  • 37.
    Vanheel, Hanne
    et al.
    Katholieke University of Leuven, Belgium .
    Vicario, Maria
    University of Autonoma Barcelona, Spain Centre Invest Biomed Red Enfermedades Hepat and Digest, Spain .
    Vanuytsel, Tim
    Katholieke University of Leuven, Belgium .
    Van Oudenhove, Lukas
    Katholieke University of Leuven, Belgium .
    Martinez, Cristina
    University of Autonoma Barcelona, Spain .
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Pardon, Nicolas
    Katholieke University of Leuven, Belgium .
    Santos, Javier
    University of Autonoma Barcelona, Spain Centre Invest Biomed Red Enfermedades Hepat and Digest, Spain .
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Tack, Jan
    Katholieke University of Leuven, Belgium .
    Farre, Ricard
    Katholieke University of Leuven, Belgium Centre Invest Biomed Red Enfermedades Hepat and Digest, Spain .
    Impaired duodenal mucosal integrity and low-grade inflammation in functional dyspepsia2014In: Gut, ISSN 0017-5749, E-ISSN 1468-3288, Vol. 63, no 2, p. 262-271Article in journal (Refereed)
    Abstract [en]

    Objective Functional dyspepsia (FD) is an extremely common functional gastrointestinal disorder, the pathophysiology of which is poorly understood. We hypothesised that impaired intestinal barrier function is involved in the onset and persistence of this disorder by inducing low-grade inflammation. Therefore, our aim was to evaluate duodenal mucosal integrity and low-grade inflammation in patients with FD. Design Duodenal biopsy specimens were obtained from 15 patients with FD fulfilling the Rome III criteria and 15 age- and gender-matched healthy volunteers. Transepithelial electrical resistance (TEER) and paracellular permeability were measured in Ussing chambers. Expression of cell-to-cell adhesion proteins was evaluated by real-time PCR, western blot and/or immunofluorescence. Numbers of mast cells, eosinophils and intraepithelial lymphocytes were assessed by immunohistochemistry. Results Patients with FD displayed lower TEER and increased paracellular passage compared with healthy controls, which is indicative of impaired mucosal integrity. In addition, abnormal expression of cell-to-cell adhesion proteins at the level of tight junctions, adherens junctions and desmosomes was shown. Furthermore, patients were characterised by the presence of low-grade inflammation, as demonstrated by increased infiltration of mucosal mast cells and eosinophils. A significant association between the expression level of several cell-to-cell adhesion proteins, the extent of increased permeability and the severity of low-grade inflammation was found. Conclusions These findings challenge the classical paradigm that patients with FD show no structural changes in the gastrointestinal tract. We suggest that impaired intestinal barrier function is a pathophysiological mechanism in FD. Thus, restoration of intestinal barrier integrity may be a potential therapeutic target for treating patients with FD.

  • 38.
    Velin Keita, Åsa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Ericson, Ann-Charlott
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Braaf, Ylva
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Wallon, Conny
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Increased antigen and bacterial uptake in follicle-associated epithelium induced by chronic psychological stress in rats2004In: Gut, ISSN 0017-5749, Vol. 53, no 4, p. 494-500Article in journal (Refereed)
    Abstract [en]

    Background: Chronic stress affects the course of inflammatory bowel disease and experimental colitis, and may also initiate intestinal inflammation in rats.

    Aim: To investigate the effects of stress on the M cell containing follicle associated epithelium, specialised in antigen uptake.

    Subjects and methods: Wistar rats were submitted to acute water avoidance stress for one hour or chronic water avoidance stress for 1 hour/day for 10 consecutive days. Permeability to 51Cr-EDTA, horseradish peroxidase, and chemically killed Escherichia coli K-12 was studied in both villus and follicle associated epithelium in Ussing chambers. Segments were further examined by light, electron, and confocal microscopy.

    Results: Acute stress increased horseradish peroxidase flux in villus as well as in follicle associated epithelium. Chronic stress further increased permeability to horseradish peroxidase in villus and follicle associated epithelium, in the latter by almost fourfold. Moreover, chronic stress induced over 30 times increased E coli passage in follicle associated epithelium whereas there was no significant increase in villus epithelium. Bacterial uptake was confirmed by confocal microscopy showing fluorescent bacteria penetrating and passing through the epithelial surface.

    Conclusions: These results show that the barrier function of follicle associated epithelium can be modulated, and that chronic stress enhances the uptake of luminal antigens and bacteria via the follicle associated epithelium. This can increase antigen exposure in Peyer’s patches thereby having implications in the initiation of proinflammatory immune responses within the intestinal mucosa.

  • 39.
    Velin, Åsa
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Ander, Stefan
    Johansson, Kenth
    Trulsson, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Smeds, Staffan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, GE: endokir.
    Inverse relation between mRNA synthesis and secretion of parathyroid hormone in athymic mice grafted with human parathyroid tissue2001In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 109, no 3, p. 235-240Article in journal (Refereed)
    Abstract [en]

    Parathyroid hormone (PTH) mRNA in original and transplanted human adenomatous parathyroid tissue and human serum intact PTH (S-iPTH) was measured in athymic mice at 4, 7, 14, and 28 days after transplantation. Parathyroid tissue was obtained during surgery for hyperparathyroidism and implanted subcutaneously. PTH mRNA detection was done with RT-PCR followed by membrane blot and hybridisation and S-iPTH was analysed using a human specific immunoradiometric method. At 4 days, PTH mRNA was 79.6 ▒ 5.3% (mean ▒ SE) of that in original tissue whereas S-iPTH was only 5.4 ng/l. At 28 days, PTH mRNA was significantly reduced to 60.7▒4.1% whereas S-iPTH was increased to 192 ng/l. The reduced PTH mRNA expression in the transplants at 28 days may be explained by an inhibited DNA transcription. The presence of human S-iPTH in transplanted mice at 4 days may be due to cell disintegration and diffusion. The gradual increase in S-iPH during the experimental period probably reflects increased transplant cell volume and improved graft revascularisation.

  • 40.
    Velin, Åsa
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Herder, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Molecular and Immunological Pathology.
    Johansson, Kenth
    Trulsson, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery.
    Smeds, Staffan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Surgery. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, GE: endokir.
    Telomerase is not activated in human hyperplastic and adenomatous parathyroid tissue2001In: European Journal of Endocrinology, ISSN 0804-4643, E-ISSN 1479-683X, Vol. 145, no 2, p. 161-164Article in journal (Refereed)
    Abstract [en]

    Background: Telomerase is a specific enzyme that appears to have a key role in cellular senescence and the progression of neoplastic tissue. High telomerase activity has been found in several cancers, but not in most normal and benign tissue. Little is known about the influence of telomerase on the abnormal growth associated with hyperparathyroidism. Objective: To analyse telomerase activity in parathyroid tissue obtained from 29 patients undergoing surgery for primary hyperparathyroidism. Design: Tissue for telomerase activity measurements was collected from six hyperplastic, 20 adenomatous and 22 normal parathyroid glands. Methods: The highly sensitive PCR-based telomeric repeat amplification protocol, TRAP, combined with ELISA, was used to detect telomerase activity in tissue extracts containing 3.0 ╡g protein. Result: Telomerase was not activated in any of the analysed tissue by 3 ╡g protein. Reassay of 12 samples containing 6.0 ╡g protein verified these negative TRAP results. Conclusion: Our findings indicate that telomerase is not a part of the mechanism promoting parathyroid proliferation and the underlying conditions remain to be determined.

  • 41.
    Wallon, Conny
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Yang, P.
    Intestinal Disease Research Programme, McMaster University, Hamilton, Canada.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences.
    Ericson, Ann-Charlott
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    McKay, D. M.
    Department of Physiology and Biophysics, University of Calgary, Canada.
    Sherman, P. M.
    Departments of Paediatrics and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
    Perdue, M. H.
    Intestinal Disease Research Programme, McMaster University, Hamilton, Canada.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Corticotropin releasing hormone (CRH) regulates macromolecular permeability via mast cells in normal human colonic biopsies in vitro2008In: Gut, ISSN 0017-5749, E-ISSN 1468-3288, Vol. 57, no 1, p. 50-58Article in journal (Refereed)
    Abstract [en]

    Objective: Persistent stress and life events affect the course of ulcerativecolitis and irritable bowel syndrome by largely unknown mechanisms.Corticotropin-releasing hormone (CRH) has been implicated asan important mediator of stress-induced abnormalities in intestinalmucosal function in animal models, but to date no studies inhuman colon have been reported. The aim was to examine the effectsof CRH on mucosal barrier function in the human colon and toelucidate the mechanisms involved in CRH-induced hyper-permeability.

    Design: Biopsies from 39 volunteers were assessed for macromolecularpermeability (horseradish peroxidise (HRP), 51Cr-EDTA), andelectrophysiology after CRH challenge in Ussing chambers. Thebiopsies were examined by electron and confocal microscopy forHRP and CRH receptor localisation, respectively. Moreover, CRHreceptor mRNA and protein expression were examined in the humanmast cell line, HMC-1.

    Results: Mucosal permeability to HRP was increased by CRH (2.8±0.5pmol/cm2/h) compared to vehicle exposure (1.5±0.4 pmol/cm2/h),p = 0.032, whereas permeability to 51Cr-EDTA and transmucosalelectrical resistance were unchanged. The increased permeabilityto HRP was abolished by -helical CRH (9-41) (1.3±0.6pmol/cm2/h) and the mast cell stabiliser, lodoxamide (1.6±0.6pmol/cm2/h). Electron microscopy showed transcellular passageof HRP through colonocytes. CRH receptor subtypes R1 and R2were detected in the HMC-1 cell line and in lamina propria mastcells in human colon.

    Conclusions: Our results suggest that CRH mediates transcellular uptake ofHRP in human colonic mucosa via CRH receptor subtypes R1 andR2 on subepithelial mast cells. CRH-induced macromolecular uptakein human colon mucosa may have implications for stress-relatedintestinal disorders.

  • 42.
    Wang, Arthur
    et al.
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Keita, Åsa V.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Phan, Van
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    McKay, Catherine M.
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Schoultz, Ida
    Nutrition-Gut-Brain Interactions Research Centre, the Faculty of Medicine, Örebro University, Örebro, Sweden.
    Lee, Joshua
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Murphy, Michael P.
    MRC-Mitochondrial Biology Unit, Cambridge, United Kingdom.
    Fernando, Maria
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Ronaghan, Natalie
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Balce, Dale
    Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
    Yates, Robin
    Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
    Dicay, Michael
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Beck, Paul L.
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Department of Medicine, University of Calgary, Calgary, Alberta, Canada.
    MacNaughton, Wallace K.
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Mckay, Derek M.
    Gastrointestinal Research Group, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada, Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
    Targeting Mitochondria-Derived Reactive Oxygen Species to Reduce Epithelial Barrier Dysfunction and Colitis2014In: American Journal of Pathology, ISSN 0002-9440, E-ISSN 1525-2191, Vol. 184, no 9, p. 2516-2527Article in journal (Refereed)
    Abstract [en]

    Epithelial permeability is often increased in inflammatory bowel diseases. We hypothesized that perturbed mitochondrial function would cause barrier dysfunction and hence epithelial mitochondria could be targeted to treat intestinal inflammation. Mitochondrial dysfunction was induced in human colon-derived epithelial cell lines or colonic biopsy specimens using dinitrophenol, and barrier function was assessed by transepithelial flux of Escherichia coil with or without mitochondria-targeted antioxidant (MTA) cotreatment. The impact of mitochondria-targeted antioxidants on gut permeability and dextran sodium sulfate (DSS)-induced colitis in mice was tested. Mitochondrial superoxide evoked by dinitrophenol elicited significant internalization and transtocation of E. coil across epithelia and control colonic biopsy specimens, which was more striking in Crohns disease biopsy specimens; the mitochondria-targeted antioxidant, MitoTEMPO, inhibited these barrier defects. Increased gut permeability and reduced epithelial mitochondrial voltage-dependent anion channel expression were observed 3 days after DSS. These changes and the severity of DSS-colitis were reduced by MitoTEMPO treatment. In vitro DSS-stimulated IL-8 production by epithelia was reduced by MitoTEMPO. Metabolic stress evokes significant penetration of commensal bacteria across the epithelium, which is mediated by mitochondria-derived superoxide acting as a signaling, not a cytotoxic, molecule. MitoTEMPO inhibited this barrier dysfunction and suppressed colitis in DSS-colitis, likely via enhancing barrier function and inhibiting proinflammatory cytokine production. These novel findings support consideration of MTAs in the maintenance of epithelial barrier function and the management of inflammatory bowel diseases.

  • 43.
    Witt, Suzanne Tyson
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Medicine and Health Sciences.
    Bednarska, Olga
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Gastroentorology.
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Icenhour, Adriane
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Jones, Michael P.
    Department of Psychology, Macquarie University, NSW, Australia.
    Elsenbruch, Sigrid
    Institute of Medical Psychology & Behavioral Immunobiology, Essen University Hospital, Essen, Germany.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Mayer, Emeran A.
    Department of Medicine, UCLA, Los Angeles, CA, United States of America.
    Walter, Susanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Gastroentorology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Interactions between gut permeability and brain structure and function in health and irritable bowel syndrome2019In: NeuroImage: Clinical, ISSN 0353-8842, E-ISSN 2213-1582, Vol. 21, article id 101602Article in journal (Refereed)
    Abstract [en]

    Changes in brain-gut interactions have been implicated in the pathophysiology of chronic visceral pain in irritable bowel syndrome (IBS). Different mechanisms of sensitization of visceral afferent pathways may contribute to the chronic visceral pain reports and associated brain changes that characterize IBS. They include increased gut permeability and gut associated immune system activation, and an imbalance in descending pain inhibitory and facilitatory mechanisms. In order to study the involvement of these mechanisms, correlations between gut epithelial permeability and live bacterial passage, and structural and functional brain connectivity were measured in women with moderate-to-severe IBS and healthy women. The relationships between gut permeability and functional and anatomical connectivity were significantly altered in IBS compared with the healthy women. IBS participants with lower epithelial permeability reported increased IBS symptoms, which was associated with increased functional and structural connectivity in endogenous pain facilitation regions. The findings suggest that relationships between gut permeability and the brain are significantly altered in IBS and suggest the existence of IBS subtypes based on these interactions.

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  • 44.
    Yakymenko, Olena
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Schoultz, Ida
    Department of Medical Sciences, Faculty of Health and Medicine, Örebro University, Örebro, Sweden.
    Gullberg, Elisabet
    Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Clinical and Experimental Medicine.
    Ström, Magnus
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Gastroentorology.
    Almer, Sven
    Department of Medicine, Karolinska Institutet, Stockholm, Sweden / GastroCentrum, Karolinska University Hospital, Stockholm, Sweden.
    Wallon, Conny
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Wang, Arthur
    Gastrointestinal Research Group, Cumming School of Medicine, University of Calgary, Calgary, Canada..
    Keita, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Campbell, Barry J.
    Gastroenterology Research Unit, Department of Cellular and Molecular Physiology, University of Liverpool, Liverpool, UK.
    McKay, Derek M.
    Gastrointestinal Research Group, Cumming School of Medicine, University of Calgary, Calgary, Canada.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Infliximab restores colonic barrier to adherent-invasive E. coli in Crohn's disease via effects on epithelial lipid rafts2018In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, E-ISSN 1502-7708, Vol. 53, no 6, p. 677-684Article in journal (Refereed)
    Abstract [en]

    Objective: Infliximab is important in the therapeutic arsenal of Crohn’s disease (CD). However, its effect on mucosal barrier function is not fully understood. Adherent-invasive Escherichia coli (AIEC) are important in CD pathophysiology, but the transmucosal uptake routes are partly unknown. We investigated effects of infliximab on uptake of colon-specific AIEC HM427 across CD colonic mucosa.

    Materials and methods: Endoscopic biopsies from non-inflamed colon of seven patients with CD, before and after two infliximab infusions, and eight non-inflammation controls, were mounted in Ussing chambers. Paracellular permeability (51Cr-EDTA) and transmucosal passage of GFP-expressing HM427 were studied. Mechanisms of HM427 transepithelial transport were investigated in Caco-2 monolayers treated with TNF, in the presence of infliximab and/or endocytosis inhibitors.

    Results: Before infliximab treatment, colonic passage of HM427 [CD: 2475 CFU (450–3000); controls 1163(225–1950)] and 51Cr-EDTA permeability were increased in CD (p < .05), but were restored to control levels by infliximab (CD: 150 (18.8–1069)). In TNF-exposed Caco-2 monolayers HM427 transport and lipid rafts/HM427 co-localization was decreased by infliximab. The lipid raft inhibitor methyl-β-cyclodextrin decreased HM427 transport.

    Conclusion: Infliximab restored the colonic barrier to AIEC in CD; an effect partially mediated by blocking lipid rafts in epithelial cells. This ability likely contributes to infliximab’s clinical efficacy in colonic CD.

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