Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Intestinal Inflammation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

Can sonography diagnose acute colonic diverticulitis in patients with acute intestinal inflammation? A prospective study.

In a prospective study of 123 patients with clinical signs of acute intestinal inflammation, the sensitivity of ultrasonography in diagnosing acute colonic diverticulitis was 84.6% and the specificity 80.3%. The predictive value of a positive and a negative sonogram was 76.0% and 87.7%, respectively. Of the 52 patients with subsequently proven acute colonic diverticulitis, 44 presented sonographically with a thickened (greater than 4 mm) hypoechoic bowel wall. In 15 patients, enlarged fluid-filled bowel loops were also present. Air-containing diverticula were demonstrated in 3 patients, abscesses in 8 patients, and colovesical fistulae in 2 patients. Eight large abscesses were successfully treated without emergency surgery by percutaneous sonographically guided evacuation. The described sonographic abnormalities strongly suggest acute colonic diverticulitis, particularly when localized in the left lower abdomen.

Acute Disease↗

The inhibitory effects of alpha(2)-adrenoceptor agonists on gastrointestinal transit during croton oil-induced intestinal inflammation.

1. The peripheral effects of alpha(2)-adrenoceptor agonists were investigated in a model of intestinal inflammation induced by intragastric administration of croton oil (CO). Our hypothesis was that inflammation would 'sensitize' adrenoceptors in peripheral and/or central terminals of myenteric and submucous plexus neurones, and enhance systemic effects of alpha(2)-adrenoceptor agonists. 2. Male swiss CD-1 mice, received intragastrically CO (0.05 ml), castor oil (CA, 0.1 ml) or saline (SS) 3 h before the study: gastrointestinal transit (GIT) was evaluated 20 min afterwards with a charcoal meal. The presence of inflammation was assessed by electron microscopy. 3. The intragastric administration of CA or CO caused an increase in GIT and weight loss, but only CO induced an inflammatory response. Both clonidine (imidazoline1/alpha(2)-agonist) and UK-14304 (alpha(2)-agonist) produced dose-related inhibitions of GIT in all groups. During inflammatory diarrhoea (CO), potencies of systemic (s.c.) clonidine and UK-14304 were significantly increased 3.5 and 2.1 times, respectively, while potencies remained unaltered in the presence of diarrhoea without inflammation (CA). The effects were reversed by administration (s.c.) of receptor-specific adrenoceptor antagonists, but not by naloxone. 4. Clonidine was 8.3 (SS) and 2.8 (CO) times more potent when administered intracerebroventricularly (i.c.v.), than when administered s.c. Inflammation of the gut did not alter the potency of i.c.v. clonidine, demonstrating that enhanced effects of s.c. clonidine are mediated by peripheral receptors. During inflammation, i.c.v. efaroxan did not antagonize low doses of s.c. clonidine (ED20 and ED50S), but partially reversed ED80S, further supporting the peripheral effects of the agonists in CO treated animals. 5. The results demonstrate that inflammation of the gut enhances the potency of alpha(2)-adrenoceptor agonists by a peripheral mechanism. The results also suggest that the inflammatory response induces an up-regulation or sensitization of alpha(2)-adrenoceptors and/or imidazoline receptors.

Adrenergic alpha-2 Receptor Agonists↗

Vanin-1(-/-) mice show decreased NSAID- and Schistosoma-induced intestinal inflammation associated with higher glutathione stores.

Vanin-1 is a membrane-anchored pantetheinase highly expressed in the gut and liver. It hydrolyzes pantetheine to pantothenic acid (vitamin B5) and the low-molecular-weight thiol cysteamine. The latter is believed to be a key regulating factor of several essential metabolic pathways, acting through sulfhydryl-disulfide exchange reactions between sulfhydryl groups of the enzymes and the oxidized form, cystamine. Its physiological importance remains to be elucidated, however. To explore this point, we developed Vanin-1-deficient mice that lack free cysteamine. We examined the susceptibility of deficient mice to intestinal inflammation, either acute (NSAID administration) or chronic (Schistosoma infection). We found that Vanin-1(-/-) mice better controlled inflammatory reaction and intestinal injury in both experiments. This protection was associated with increased gamma-glutamylcysteine synthetase activity and increased stores of reduced glutathione, as well as reduced inflammatory cell activation in inflamed tissues. Oral administration of cystamine reversed all aspects of the deficient phenotype. These findings suggest that one cysteamine function is to upregulate inflammation. Consequently, the pantetheinase activity of Vanin-1 molecule could be a target for a new anti-inflammatory strategy.

Amidohydrolases↗

Peripheral effects of opioids in a model of intestinal inflammation in mice.

The study evaluates the peripheral component of the antitransit effects of opioids during acute intestinal inflammation induced by the intragastric administration of croton oil (CO) in mice. Gastrointestinal transit was measured 3 h after CO or saline (SS) administration with a charcoal meal. In both groups, the effects of mixed (morphine, fentanyl, U-50488H) and peripherally acting (N-methylmorphine, PL017, ICI-204448) opioids and their antagonism by naloxone and naloxone methiodide were established. During inflammation, the potencies of morphine and N-methylmorphine increased 3 times, and those of fentanyl and PL017, 1.9 times. The effects were reversed by naloxone (0.1 mg/kg) and naloxone methiodide (0.3 mg/kg). No dose-response relationships could be elicited with U-50488H or ICI-204448, and their antitransit effects were analogous in SS- and CO-treated animals. These results show that during inflammation the enhanced antitransit effects of opioids are primarily mediated by interaction with opioid receptors located at peripheral sites. In addition, inflammation of the gut seems to induce a sensitization of mu-but not kappa-opioid receptors.

Animals↗

Assessment of the usefulness of a diagnostic test: a survey of patient preference for diagnostic techniques in the evaluation of intestinal inflammation.

BACKGROUND: In order to assess the usefulness of radiolabeled white cell scanning in the diagnosis of intestinal inflammation, subjects were asked to rank several dimensions of preference for white cell scanning in relation to other diagnostic tests. Two groups were surveyed: one known to have inflammatory bowel disease and the second not familiar in most cases with the tests. Subjects were asked to rank preference for each of seven tests: radiolabeled white cell scan, colonoscopy, barium enema, sigmoidoscopy, enteroclysis, stool analysis and laparotomy for the diagnosis of IBD and impressions of discomfort, embarrassment, inconvenience and danger related to each test. Mean rank scores were calculated, test ranks compared within groups and significance determined by the Wilcoxon rank test. RESULTS: Significant differences were seen in overall preference for white cell scan over barium enema and colonoscopy (p < 0.01) in both survey groups. Perceived discomfort and embarrassment demonstrated similar rankings. CONCLUSION: This patient preference combined with the reported accuracy of white cell scanning further establishes the usefulness of this means of IBD diagnosis.

Adolescent↗

Activation of A2A adenosine receptor attenuates intestinal inflammation in animal models of inflammatory bowel disease.

BACKGROUND & AIMS: Adenosine has been implicated as an important regulator of the inflammatory response. Four subtypes of adenosine receptors (A 1 , A 2A , A 2B , and A 3 ) have been described, of which A 2A potentially inhibits inflammation. The aim of this study was to investigate the role of A 2A in mucosal inflammation by administering a selective A 2A agonist (ATL-146e) to experimental models of inflammatory bowel disease. METHODS: The anti-inflammatory effects of ATL-146e were studied in the acute and chronic rabbit formalin-immune complex models of colitis and the SAMP1/YitFc mouse model of spontaneous ileitis. RESULTS: ATL-146e significantly reduced the acute inflammatory index and tissue necrosis compared with vehicle ( P < .01) in the acute model of rabbit immune colitis. In the chronic rabbit immune colitis model, ATL-146e significantly suppressed inflammatory cell infiltration into the colonic mucosa ( P < .05) and prevented mortality. The administration of ATL-146e significantly decreased the chronic inflammatory index ( P < .01) and villus distortion index ( P < .01) in the ileum of SAMP1/YitFc mice, and ameliorated adoptively transferred ileitis in severe combined immunodeficient mice injected with CD4 + T cells from SAMP1/Yit mice ( P < .05). Tumor necrosis factor, interferon gamma, and interleukin 4 concentrations were significantly suppressed by ATL-146e treatment in supernatants from cultures of mesenteric lymph node cells of SAMP1/YitFc mice ( P < .05 vs vehicle-treated mice). CONCLUSIONS: A 2A adenosine receptor activation by ATL-146e significantly reduced inflammation in the intestinal mucosa. This effect was associated with decreased leukocyte infiltration and inhibition of proinflammatory cytokines. Activation of A 2A by selective agonism may therefore serve as a novel therapy for the treatment of inflammatory bowel disease.

Acute Disease↗

Histopathology of intestinal inflammation related to reactive arthritis.

This study has identified a group of patients with inflammatory chronic, or relapsing acute arthritis who even in the absence of gastrointestinal symptoms have histological evidence of ileocolitis. At colonoscopy simultaneous biopsies of the terminal ileum and colon were taken from 108 patients with reactive arthritis (n = 55) or ankylosing spondylitis (n = 53), 47 patients with other rheumatic diseases and 19 control patients suffering from colonic polyps, adenocarcinoma, or chronic constipation. All control patients and all but one patient with rheumatoid arthritis, juvenile chronic arthritis, systemic lupus erythematosus, lumbar back ache, and psoriatic arthritis did not have histological evidence of acute or chronic inflammatory bowel disease. In contrast, in 30 of 35 (56.6%) patients with ankylosing spondylitis, and in 37 of 55 (67%) patients with reactive arthritis, regardless of HLA B27 phenotype, there was histological evidence of inflammatory bowel disease with features either of acute enterocolitis, or early Crohn's disease. Only 18 of 67 (27%) of the patients with histological gut inflammation, however, had intestinal symptoms.

Adolescent↗

Gut lavage IgG and interleukin 1 receptor antagonist:interleukin 1 beta ratio as markers of intestinal inflammation in children with inflammatory bowel disease.

BACKGROUND: Whole gut lavage is currently used as preparation before radiological or endoscopic examination of the large bowel. AIM: To validate the gut lavage technique for the assessment of mucosal inflammation, by measuring intestinal IgG and interleukin 1 beta (IL-1 beta) in the fluid obtained. PATIENTS: Sixteen children with Crohn's disease (CD), 14 with ulcerative colitis (UC), and 22 age matched controls. METHODS: Isotonic, non-absorbable polyethylene glycol based lavage solution was given orally or by nasogastric tube. Clear fluid was collected, filtered, and treated with protease inhibitors. IgG, IL-1 beta and IL-1-receptor antagonist (IL-1-ra) were measured by sandwich enzyme linked immunosorbent assay (ELISA). RESULTS: In patients with UC and CD, IgG and IL-1 beta levels were significantly (p < 0.001) higher than in controls. A positive correlation (p < 0.05) was found with disease activity scores. IL-1-ra levels were not significantly different in UC and CD, when compared with controls, but the IL-1-ra:IL-1 beta ratio was significantly (p < 0.01) lower in patients with UC and CD, and negatively (p < 0.001) correlated with IgG levels in lavage fluid. CONCLUSIONS: Gut lavage fluid IgG and IL-1 beta levels and IL-1-ra:IL-1 beta ratio may provide objective discrimination between active and inactive disease in children with inflammatory bowel disease.

Adolescent↗

Mucosal immunity and inflammation. II. The yin and yang of T cells in intestinal inflammation: pathogenic and protective roles in a mouse colitis model.

Inflammatory bowel disease (IBD) is a multifactorial immune disorder of uncertain etiology. The advent of several mouse models of mucosal inflammation that resemble IBD has provided insight into the mechanisms governing both normal and pathological mucosal immune function. In a widely used adoptive transfer model, the injection into immunodeficient mice of a subset of CD4(+) T lymphocytes, the CD4(+)CD45RBhigh cells, leads to inflammation of the intestine. Pathogenesis is due in part to the secretion of proinflammatory cytokines. The induction of colitis can be prevented by cotransfer of another CD4(+) subpopulation, the CD4(+)CD45RBlow T cells. This population behaves analogously to the CD4(+)CD45RBhigh population in terms of the acquisition of activation markers and homing to the host intestine. However, their lymphokine profile when activated is different, and anti-inflammatory cytokines secreted and/or induced by CD4(+)CD45RBlow T cells prevent colitis. In this themes article, a description of the adoptive transfer model is given, the factors that promote and prevent colitis pathogenesis are discussed, and some controversial aspects of the model are addressed.

Animals↗

Control of intestinal inflammation by regulatory T cells.

Regulatory T(Treg)-cell populations have been identified in a number of disease models. In this review we focus on the role of naturally occurring Treg cells in the control of intestinal inflammation. Specifically, we discuss their mechanism of action with particular emphasis on the role of anti-inflammatory cytokines and cell surface molecules.

Animals↗

Trefoil peptide TFF2 treatment reduces VCAM-1 expression and leukocyte recruitment in experimental intestinal inflammation.

There is evidence for a beneficial effect of trefoil peptides in animal models of gastric damage and intestinal inflammation, but the optimal treatment strategy and the mechanistic basis have not been explored thoroughly. It has been suggested that these proteins may modulate the inflammatory response. The aims of this study were to compare the protective and curative value of systemic and topical trefoil factor family (TFF)2 administration in dextran sulfate sodium-induced experimental colitis and to investigate the relationship between the therapeutic effects of TFF2 and modulation of leukocyte recruitment and expression of cell adhesion molecules. Clinical and morphologic severity of colitis was evaluated at the end of the study (Day 10). Leukocyte-endothelial cell interactions were determined in colonic venules by fluorescence intravital microscopy. The expression of cell adhesion molecules vascular cell adhesion molecule 1 (VCAM-1) and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) was measured by the dual radiolabeled monoclonal antibody technique. Pretreatment with TFF2 by subcutaneous or intracolonic (ic) route ameliorated the clinical course of colitis, and the luminal route had a significantly superior effect. This beneficial effect was correlated with significant reductions in endothelial VCAM-1 but not MAdCAM-1 expression and leukocyte adhesion to intestinal venules, which returned to levels similar to those of controls. In established colitis, ic TFF2 treatment did not modify the severity of colonic lesions. In conclusion, TFF2 is useful in the treatment of colitis, and topical administration is superior to the systemic route. Reduction in adhesion molecule expression and leukocyte recruitment into the inflamed intestine contributes to the beneficial effect of this treatment.

Animals↗

Effects of morphine and liposomal morphine in a model of intestinal inflammation in mice.

We have investigated the antitransit effects of free and liposomal morphine in a model of intestinal inflammation. Mice received saline or croton oil orally, 3 h prior to evaluation, and gastrointestinal transit was measured 20 min afterwards. Peak/duration of effects, potency (ED50) and antagonism by naloxone and naloxone methiodide were evaluated. Peak effects occurred 30 and 40 min after administration of morphine and liposomal morphine, respectively. Encapsulated morphine had a more pronounced and prolonged effect than morphine. Comparison of the ED50S demonstrated that the potency of liposomal morphine was 3.5 times higher than that of morphine during inflammation; in addition, inflammation increased the potency of morphine and liposomal morphine, 3 and 9.2 times, respectively. The effects of morphine and liposomal morphine in croton oil-treated mice were reversed by naloxone and naloxone methiodide. The results show that during inflammation, the potency and duration of the antitransit effects of morphine are significantly enhanced by encapsulation.

Animals↗

Protective effect of superoxide dismutase in radiation-induced intestinal inflammation.

PURPOSE: To analyze the therapeutic value of Cu/Zn-superoxide dismutase (SOD1) supplementation in an experimental model of radiation-induced intestinal inflammation and explore its mechanistic effects. METHODS AND MATERIALS: Mice were subjected to abdominal irradiation with 10 Gy or sham irradiation and studied 24 or 72 hours after radiation. Groups of mice were treated with 0.1, 4, or 6 mg/kg/day of SOD1 or vehicle. Leukocyte-endothelial cell interactions in intestinal venules were assessed by intravital microscopy. Endothelial intercellular adhesion molecule-1 (ICAM-1) expression was determined with radiolabeled antibodies. Effects of SOD1 on histologic damage and levels of lipid hydroperoxides were also measured. RESULTS: A significant increase in the flux of rolling leukocytes and number of firmly adherent leukocytes in intestinal venules was observed at 24 and 72 hours after irradiation. Treatment with SOD1 had no effect on leukocyte rolling but significantly and dose-dependently decreased firm leukocyte adhesion to intestinal venules. Treatment with SOD1 at doses that reduced leukocyte recruitment abrogated the increase in hydroperoxides in intestinal tissue and ICAM-1 upregulation in intestinal endothelial cells. The inflammatory score, but not a combined histology damage score, was also significantly reduced by SOD1. CONCLUSIONS: Treatment with SOD1 decreases oxidative stress and adhesion molecule upregulation in response to abdominal irradiation. This is associated with an attenuation of the radiation-induced intestinal inflammatory response.

Animals↗

Human mucosa/submucosa interactions during intestinal inflammation: involvement of the enteric nervous system in interleukin-8 secretion.

Interleukin-8 (IL-8) is a key chemokine upregulated in various forms of intestinal inflammation, especially those induced by bacteria such as Clostridium difficile (C. difficile). Although interactions between different mucosal and submucosal cellular components have been reported, whether such interactions are involved in the regulation of IL-8 secretion during C. difficile infection is unknown. Moreover, whether the enteric nervous system, a major component of the submucosa, is involved in IL-8 secretion during an inflammatory challenge remains to be determined. In order to investigate mucosa/submucosa interactions that regulate IL-8 secretion, we co-cultured human intestinal mucosa and submucosa. In control condition, IL-8 secretion in co-culture was lower than the sum of the IL-8 secretion of both tissue layers cultured alone. Contrastingly, IL-8 secretion increased in co-culture after mucosal challenge with toxin B of C. difficile through an IL-1 beta-dependent pathway. Moreover, we observed that toxin B of C. difficile increased IL-8 immunoreactivity in submucosal enteric neurones in co-culture and in intact preparations of mucosa/submucosa, through an IL-1 beta-dependent pathway. IL-1 beta also increased IL-8 secretion and IL-8 mRNA expression in human neuronal cell lines (NT2-N and SH-SY5Y), through p38 and ERK1/2 MAP kinase-dependent pathways. Our results demonstrate that mucosa/submucosa interactions regulate IL-8 secretion during inflammatory processes in human through IL-1 beta-dependent pathways. Finally we observed that human submucosal neurones synthesize IL-8, whose production in neurones is induced by IL-1 beta via MAPK-dependent pathways.

Aged↗

VEGF, basic-FGF, and TGF-beta in Crohn's disease and ulcerative colitis: a novel mechanism of chronic intestinal inflammation.

OBJECTIVE: Inflammatory bowel disease (IBD), the precise etiology of which remains unknown, is comprised of two forms of chronic intestinal inflammation; ulcerative colitis (UC) and Crohn's disease (CD). Recent evidence increasingly suggests that IBD is the result of dysfunctional immunoregulation manifested by inappropriate production of mucosal cytokines. An abnormal microcirculatory system has also been implicated in its pathogenesis. To elucidate the mechanism of ischemic change in IBD, we assesse serum concentration levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF), and plasma level of endothelin-1 (ET-1). We also investigated the expression of VEGF, b-FGF, and transforming growth factor-beta1,2,3 (TGF-beta1,2,3) in tissue by immunostaining. METHODS: Blood samples were obtained from 11 patients with UC, 11 patients with CD, and 10 patients as controls. Paraffin-embedded samples were used for an immunohistochemical study. RESULTS: The concentration levels (in picograms per milliliter) were as follows: for ET-1, UC: 127+/-47.0, CD: 167.3+/-35.1, and controls (asthma: 38.5+/-23.8, p < 0.01; diverticulitis: 40.5+/-25.6, p < 0.01), for b-FGF, UC: 9.2+/-1.9, CD: 9.1+/-1.5, and controls (asthma: 5.0+/-0, p < 0.01; diverticulitis: 5.0+/-0, p < 0.01), for VEGF, UC: 659.8+/-181.0, CD: 740.0+/-182.3, and controls (asthma: 193.7+/-58.7, p < 0.01; diverticulitis: 199.6+/-59.7, p < 0.01). The levels of VEGF and b-FGF were significantly higher in active IBD than those in the controls. There was a significant positive correlation among the serum levels of VEGF and b-FGF and the plasma level of ET-1; that is, elevated VEGF, b-FGF, and ET-1 levels correlated well with each other. Immunohistochemical studies showed increased venula in the submucosa and lamina propria. Overexpression of VEGF and b-FGF in endothelial cells was revealed and TGF-beta2 and TGF-beta3 were found in inflammatory cells of active IBD, but no change was observed around the vessels in the controls. CONCLUSIONS: It is suggested that the reciprocal reaction of these cytokines may contribute to angiogenesis in IBD b inducing intestinal ischemia through vasoconstriction.

Adult↗

Experimental models to study molecular mechanisms underlying intestinal inflammation.

Experimental animal models, particularly the newer mouse models, have convincingly demonstrated that CD+ T cells play a central role in chronic intestinal inflammation. Such CD4+ effector T cells are induced by the bacterial flora. In at least one model, it is conventional protein antigens that are stimulating these pathogenic T cells. The antigens driving disease seem to be a selective subset of immunodominant proteins, likely derived from a subset of organisms. Multiple genes contribute to colitis susceptibility and a number of these genes are being localized.

Animals↗

Macrophage-derived IL-18-mediated intestinal inflammation in the murine model of Crohn's disease.

BACKGROUND & AIMS: Crohn's disease (CD) is associated with an increased number of infiltrating macrophages, which release a variety of proinflammatory cytokines. Interleukin (IL)-18 has been implicated in the modulation of mucosal CD4(+) T cells towards Th1 responses, which are implicated in the pathogenesis of CD. Here we assess the role of macrophages and of IL-18 in the murine model of intestinal inflammation that mimics the immunologic characteristics of human CD. METHODS: Colitis was induced in C57BL/6 mice immunized with 2,4,6-trinitrobenzene sulfonic acid (TNBS) followed by rectal administration of TNBS in ethanol. Mice were treated with either an antibody directed against macrophages conjugated to the ribosome-inactivating protein saporin (anti-Mac-1-saporin) or with a neutralizing antibody against IL-18. In addition, we assessed whether an identical TNBS immunization/challenge protocol could induce colitis in IL-18(-/-) mice. RESULTS: The colonic mucosa of TNBS-treated mice was marked by infiltration of Mac-1-positive macrophages and up-regulation of IL-18. The administration of the anti-Mac-1-saporin antibody or the neutralizing anti-IL-18 antibody resulted in a dramatic attenuation of mucosal inflammation in this model. In addition, TNBS was unable to induce significant colitis in the IL-18(-/-) mice. CONCLUSIONS: Our data underscore the pivotal role of macrophages, and the macrophage-derived IL-18, in the establishment of TNBS-induced colitis in mice. Our results highlight the potential use of therapy directed against IL-18 in the treatment of patients with CD.

Animals↗

Therapeutic approaches to chronic intestinal inflammation by specific targeting of mucosal IL-7/IL-7R signal pathway.

Inflammatory bowel disease is thought to result from inappropriate activation of mucosal immune responses. Intestinal epithelial cells produce interleukin (IL)-7 that serves as a regulatory factor for IL-7 receptor (IL-7R)(+) mucosal lymphocytes. The pivotal role of mucosal IL-7/IL-7R dependent signals in the activation of mucosal immune responses that lead to the development of chronic intestinal inflammation are demonstrated. Therapeutic approaches targeting IL-7/IL-7R signal pathway may be feasible in the treatment of inflammatory bowel disease.

Animals↗