interleukin-8 and Ileitis

To characterize a specific population of TcdA-affected myenteric neurons and investigate the role of the P2X7 receptor in TcdA-induced ileal inflammation, cell death, and the changes in the enteric nervous system in mice.. Swiss mice were used to model TcdA-induced ileitis in ileal loops exposed to TcdA (50 μg/Loop) for 4 h. To investigate the role of the P2X7 receptor, Brilliant Blue G (50 mg/kg, i.p.), which is a nonspecific P2X7 receptor antagonist, or A438079 (0.7 μg/mouse, i.p.), which is a competitive P2X7 receptor antagonist, were injected one hour prior to TcdA challenge. Ileal samples were collected to analyze the expression of the P2X7 receptor (by quantitative real-time polymerase chain reaction and immunohistochemistry), the population of myenteric enteric neurons (immunofluorescence), histological damage, intestinal inflammation, cell death (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling), neuronal loss, and S100B synthesis (immunohistochemistry).. TcdA upregulated (. Our findings demonstrated that TcdA induced the upregulation of the P2X7 receptor, which promoted enteric neuron loss, S100B synthesis, tissue damage, inflammation, and cell death in the mouse ileum. These findings contribute to the future directions in understanding the mechanism involved in intestinal dysfunction reported in patients after

Topics: Animals; Apoptosis; Bacterial Toxins; Biotin; Calbindin 2; Choline O-Acetyltransferase; Clostridioides difficile; DNA Nucleotidylexotransferase; Enterotoxins; Ileitis; Inflammation; Interleukin-6; Interleukin-8; Mice; Neurons; Purinergic P2X Receptor Antagonists; Receptors, Purinergic P2X7; Tumor Necrosis Factor-alpha

Dysbiosis has been recently demonstrated in patients with ankylosing spondylitis (AS) but its implications in the modulation of intestinal immune responses have never been studied. The aim of this study was to investigate the role of ileal bacteria in modulating local and systemic immune responses in AS.. Ileal biopsies were obtained from 50 HLA-B27. Adherent and invasive bacteria were observed in the gut of patients with AS with the bacterial scores significantly correlated with gut inflammation. Impairment of the gut vascular barrier (GVB) was also present in AS, accompanied by significant upregulation of zonulin, and associated with high serum levels of LPS, LPS-BP, iFABP and zonulin. In in vitro studies zonulin altered endothelial tight junctions while its epithelial release was modulated by isolated AS ileal bacteria. AS circulating monocytes displayed an anergic phenotype partially restored by ex vivo stimulation with LPS+sCD14 and their stimulation with recombinant zonulin induced a clear M2 phenotype. Antibiotics restored tight junction function in HLA-B27 TG rats.. Bacterial ileitis, increased zonulin expression and damaged intestinal mucosal barrier and GVB, characterises the gut of patients with AS and are associated with increased blood levels of zonulin, and bacterial products. Bacterial products and zonulin influence monocyte behaviour.

Topics: Acute Disease; Acute-Phase Proteins; Adherens Junctions; Animals; Anti-Bacterial Agents; Antigens, CD; Bacteria; Caco-2 Cells; Cadherins; Carrier Proteins; Case-Control Studies; Cholera Toxin; Chronic Disease; Dysbiosis; Endothelium; Fatty Acid-Binding Proteins; Gene Expression; Haptoglobins; HLA-B27 Antigen; Human Umbilical Vein Endothelial Cells; Humans; Ileitis; Ileum; Interleukin-8; Intestinal Mucosa; Junctional Adhesion Molecule A; Lipopolysaccharides; Membrane Glycoproteins; Membrane Proteins; Monocytes; Permeability; Protein Precursors; Rats; Rats, Transgenic; RNA, Messenger; Spondylitis, Ankylosing; Tight Junctions; Up-Regulation

To determine whether the carbon monoxide (CO)-releasing molecules (CORM)-liberated CO suppress inflammatory responses in the small intestine of septic mice.. The C57BL/6 mice (male, n = 36; weight 20 ± 2 g) were assigned to four groups in three respective experiments. Sepsis in mice was induced by cecal ligation and puncture (CLP) (24 h). Tricarbonyldichlororuthenium (II) dimer (CORM-2) (8 mg/kg, i.v.) was administrated immediately after induction of CLP. The levels of inflammatory cytokines [interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α)] in tissue homogenates were measured with enzyme-linked immunosorbent assay. The levels of malondialdehyde (MDA) in the tissues were determined. The levels of nitric oxide (NO) in tissue homogenate were measured and the expression levels of intercellular adhesion molecule 1 (ICAM-1) and inducible nitric oxide synthase (iNOS) in the small intestine were also assessed. NO and IL-8 levels in the supernatants were determined after the human adenocarcinoma cell line Caco-2 was stimulated by lipopolysaccharide (LPS) (10 g/mL) for 4 h in vitro.. At 24 h after CLP, histological analysis showed that the ileum and jejunum from CLP mice induced severe edema and sloughing of the villous tips, as well as infiltration of inflammatory cells into the mucosa. Semi-quantitative analysis of histological samples of ileum and jejunum showed that granulocyte infiltration in the septic mice was significantly increased compared to that in the sham group. Administration of CORM-2 significantly decreased granulocyte infiltration. At 24 h after CLP, the tissue MDA levels in the mid-ileum and mid-jejunum significantly increased compared to the sham animals (103.68 ± 23.88 nmol/mL vs 39.66 ± 8.23 nmol/mL, 89.66 ± 9.98 nmol/mL vs 32.32 ± 7.43 nmol/mL, P < 0.01). In vitro administration of CORM-2, tissue MDA levels were significantly decreased (50.65 ± 11.46 nmol/mL, 59.32 ± 6.62 nmol/mL, P < 0.05). Meanwhile, the tissue IL-1β and TNF-α levels in the mid-ileum significantly increased compared to the sham animals (6.66 ± 1.09 pg/mL vs 1.67 ± 0.45 pg/mL, 19.34 ± 3.99 pg/mL vs 3.98 ± 0.87 pg/mL, P < 0.01). In vitro administration of CORM-2, tissue IL-1β and TNF-α levels were significantly decreased (3.87 ± 1.08 pg/mL, 10.45 ± 2.48 pg/mL, P < 0.05). The levels of NO in mid-ileum and mid-jejunum tissue homogenate were also decreased (14.69 ± 2.45 nmol/mL vs 24.36 ± 2.97 nmol/mL, 18.47 ± 2.47 nmol/mL vs 27.33 ± 3.87 nmol/mL, P < 0.05). The expression of iNOS and ICAM-1 in the mid-ileum of septic mice at 24 h after CLP induction significantly increased compared to the sham animals. In vitro administration of CORM-2, expression of iNOS and ICAM-1 were significantly decreased. In parallel, the levels of NO and IL-8 in the supernatants of Caco-2 stimulated by LPS was markedly decreased in CORM-2-treated Caco-2 cells (2.22 ± 0.12 nmol/mL vs 6.25 ± 1.69 nmol/mL, 24.97 ± 3.01 pg/mL vs 49.45 ± 5.11 pg/mL, P < 0.05).. CORM-released CO attenuates the inflammatory cytokine production (IL-1β and TNF-α), and suppress the oxidative stress in the small intestine during sepsis by interfering with protein expression of ICAM-1 and iNOS.

Topics: Animals; Caco-2 Cells; Carbon Monoxide; Disease Models, Animal; Enteritis; Humans; Ileitis; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-8; Intestine, Small; Jejunal Diseases; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Nitric Oxide; Nitric Oxide Synthase Type II; Organometallic Compounds; Peroxidase; Sepsis; Time Factors; Tumor Necrosis Factor-alpha

Non-obese gallstone patients exhibit a diminished expression of apical sodium-dependent bile acid transporter (ASBT) in terminal ileum. Crohn's ileitis demonstrates a significant downregulation of this transporter.. To test whether subclinical ileal inflammation contributes to gallstone disease.. Biopsies from terminal ileum of female subjects with gallstone disease (n = 7), active Crohn's disease (n = 17) and controls (n = 22) were investigated. mRNA expression of ASBT, tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-8, c-jun and c-fos was measured. c-jun and c-fos protein levels were determined and hematoxylin and eosin staining was applied for ileal histology.. ASBT expression was comparably low both in gallstone (47% of controls, p = 0.0093) and Crohn's disease (42% of controls, p = 0.0008). In gallstone disease there was a non-significant trend towards elevated TNF-alpha and IL-1beta, but all cytokines were increased in active Crohn's disease. c-jun and c-fos were slightly diminished in patients with gallstones. Neither cytokines nor transcription factors correlated significantly with ASBT. The gallstone-associated ileal biopsies exhibited no histological inflammation.. Although the expression of ASBT was similarly diminished in both gallstone and Crohn's disease, subclinical ileal inflammation does not appear to be relevant in gallstone patients. The mechanisms of transcriptional repression of ASBT in both diseases are apparently different.

Topics: Adult; Aged; Case-Control Studies; Crohn Disease; Female; Gallstones; Humans; Ileitis; Ileum; Inflammation Mediators; Interleukin-1beta; Interleukin-8; Middle Aged; Organic Anion Transporters, Sodium-Dependent; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; RNA, Messenger; Symporters; Tumor Necrosis Factor-alpha

Clostridium difficile toxin A causes acute colitis associated with intense infiltration of neutrophils. Although C. difficile toxin A is known to induce nuclear factor-kappaB-mediated chemokine expression in intestinal epithelial cells, little is known about its effect on the regulation of activator protein-1 (AP-1) by mitogen-activated protein kinase (MAPK). In the present study, we investigated whether the MAPK and AP-1 signaling pathway is involved in interleukin (IL)-8 expression and enteric inflammation in response to stimulation with toxin A. Toxin A activated MAPK and AP-1 composed of c-Jun/c-Fos heterodimers in primary intestinal epithelial cells and HT-29 cell lines. Transfection with mutant genes for Ras, c-Jun, p38, or c-Jun N-terminal kinase (JNK) significantly inhibited C. difficile toxin A-induced activation of AP-1 and expression of IL-8 in HT-29 cell lines. Furthermore, the p38 inhibitor SB203580 attenuated toxin A-induced inflammation in vivo in the mouse ileum, evidenced by a significant decrease in neutrophil infiltration, villous destruction, and mucosal congestion. Our results suggest that the Ras/MAPK cascade acts as the upstream signaling for AP-1 activation and IL-8 expression in toxin A-stimulated intestinal epithelial cells and may be involved in the development of enteritis after infection with toxin A-producing C. difficile.

Topics: Animals; Bacterial Toxins; Colon; Dimerization; Disease Models, Animal; Enterotoxins; Enzyme Activation; Epithelial Cells; Genes, ras; HT29 Cells; Humans; Ileitis; Imidazoles; Interleukin-8; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Mutation; p38 Mitogen-Activated Protein Kinases; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; Pyridines; Time Factors; Transcription Factor AP-1; Transfection

An important action of interleukin 8 (IL8) is stimulation of granulocytes. The object of this study was to assess the contribution of IL8 to the leucocyte-endothelial cell interactions associated with intestinal inflammation in the rat.. Two indomethacin injections (48 and 24 hours prior to the experiments) induced a longlasting ileitis in rats. The number of adherent and emigrated leucocytes, leucocyte rolling velocity, and shear rate were monitored in normal and inflamed mesenteric postcapillary venules. Some animals received a monoclonal antibody (MAb) against IL8 or CD11b/CD18 at 24 and 12 hours prior to the experiment.. Indomethacin elicited a seven-fold increase in leucocyte adherence and a 5.4-fold increase in leucocyte emigration, while leucocyte rolling velocity was reduced by nearly 80%. The indomethacin induced increases in leucocyte adherence and emigration were significantly reduced (by 57% and 67%, respectively) while leucocyte rolling velocity was increased (to 63% of control) by the IL8-specific MAb. The level of inhibition seen with the IL8 MAb was similar to that associated with administration of a MAb directed against the leucocyte adhesion molecule CD11b/CD18.. IL8 contributes to the leucocyte-endothelial cell interactions elicited in mesenteric venules by indomethacin.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antibodies, Monoclonal; Cell Adhesion; Cell Migration Inhibition; Ileitis; Indomethacin; Interleukin-8; Leukocytes; Male; Mesenteric Veins; Microcirculation; Rats; Rats, Sprague-Dawley

Controversy exists as to whether pouchitis represents a reactivation of the immunologic mechanisms that lead to ulcerative colitis (UC). The aims of this study were to determine local levels of the cytokines: interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF alpha) in the mucosa of patients with "asymptomatic" ileoanal pouch (n = 25), pouchitis (n = 9), active UC (n = 20), normal ileum (n = 15), proctitis (n = 10), and normal colon (n = 15).. Lamina propria mononuclear cells were isolated from mucosal biopsies by enzymatic dispersion and cultured for 48 hours. Proinflammatory cytokine levels were measured in the supernatants by enzyme-linked immunosorbent assay.. IL-1 beta, IL-6, IL-8, and TNF alpha secretions were significantly greater in pouchitis and active UC than in the noninflamed ileoanal pouch and normal controls (P < 0.001). There was significant correlation (r = 0.63, P < 0.05) between levels of cytokines expressed in pouchitis and active UC.. Increased cytokine expression occurs in both active UC and pouchitis and to a lesser extent in the long-standing ileoanal pouch.

Topics: Adolescent; Adult; Aged; C-Reactive Protein; Case-Control Studies; Colitis, Ulcerative; Colon; Humans; Ileitis; Ileum; Interleukin-1; Interleukin-6; Interleukin-8; Interleukins; Intestinal Mucosa; Leukocytes, Mononuclear; Middle Aged; Orosomucoid; Proctitis; Proctocolectomy, Restorative; Tumor Necrosis Factor-alpha