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Plasma and mucosal fatty acid pattern in colectomized ulcerative colitis patients.

Patients with inflammatory bowel disease (IBD) have increased plasma n3 polyunsaturated fatty acids (PUFAs), which in ulcerative colitis (UC) patients persists six months after colectomy, suggesting a primary abnormality in fatty acid (FA) metabolism in IBD. This finding needed to be confirmed in a larger series of UC long-term colectomized patients. We aimed to assess the plasma FA pattern in UC colectomized patients with either Brooke's ileostomy (UC-BI) or ileal pouch anal anastomosis (UC-IPAA) and the mucosal FA pattern in the ileal reservoir of the UC-IPAA patients. Plasma FAs were assessed in 63 UC colectomized patients (31 with BI and 32 with IPAA) and 30 controls. In 26 UC-IPAA (8 with pouchitis and 18 without pouchitis) and in 13 healthy controls gut mucosal FAs were also investigated. FAs were detected by capillary column gas-liquid chromatography. Increased levels of saturated fatty acids (SFAs) and decreased percentages of monounsaturated fatty acids (MUFAs) were observed in both groups of patients. There were no changes in plasma n3 and n6 PUFAs. The mucosal FA pattern of the ileal reservoir consisted of increased long-chain PUFAs, specially n6 PUFA, and a decrease of their essential precursors. High percentages of SFAs and low percentages of MUFAs were also seen. The plasma FA profile previously described in IBD is not observed long-term after colectomy in UC, suggesting that it is related with the presence of inflamed intestine. High concentrations of SFAs and decreased percentages of MUFAs might represent early events in disturbed FA metabolism in IBD. The changes in FAs of the ileal reservoir, which closely resemble those found in human and experimental IBD, probably represent a common pattern of intestinal inflammation.

Adult↗

Diminished efficacy of colonic adaptation to lactulose occurs in patients with inflammatory bowel disease in remission.

Lactulose has been proposed to be beneficial in treating inflammatory bowel disease (IBD). The hypothesis is based on the prebiotic potential of lactulose. A practical approach to testing its usefulness is to determine colonic adaptation to tolerable doses in patients with IBD. Our objective was to determine if a 3-week course of lactulose will decrease BH2 and symptoms in response to an acute lactulose challenge test in control subjects and IBD patients. The design was a prospective cohort study. Subjects were given a 30-g lactulose challenge test (test 1), and then ingested 10 g of lactulose twice a day for 3 weeks before being retested (Test 2). A third test was given after a further 5-week washout period. The main outcomes were the change in 4-hr sum of BH2 (sum(4HrBH2)) values obtained every 30 min, peak BH2, and 4-hr sum of symptom score (sum(4HrSS)) during the lactulose challenge test. In addition, we also report the change in self-reported symptoms and diarrhea during the 3-week administration of lactulose. In controls, sum(4HrBH2) decreased from test 1 (380.5 +/- 56.6 ppm) to test 2 (288.6 +/- 57.4 ppm) (P < 0.05), and returned toward test 1 levels by test 3 (307.5 +/- 53.1, P > 0.5). Unlike controls, the sum(4HrBH2) in patients failed to achieve significance between test 1 (444.5 +/- 55.8 ppm), test 2 (366.5 +/- 80.7 ppm, P > 0.2) or test 3 (411.6 +/- 62.5 ppm, P > 0.2). Sum(4HrSS) results in controls followed a pattern similar to sum(4HrBH2), achieving significance only in test 2 (P < 0.02). Symptoms during the intertest periods decreased by the third week in controls (P < 0.05), but not in patients (P > 0.5). Symptoms were lower in patients and varied insignificantly both in challenges and intertest periods. In conclusion, although controls adapt to a 3-week period of lactulose ingestion, IBD patients fail to meet the criteria for adaptation. However, longer studies may be needed to establish whether IBD patients are slower to adapt.

Adaptation, Physiological↗

Altered glycosylation in inflammatory bowel disease: a possible role in cancer development.

Ulcerative colitis and Crohn's disease (together known as Inflammatory Bowel Disease or IBD) are both associated with increased risk for colorectal cancer. Although it is conventional to emphasise differences between IBD-associated and sporadic colon cancer, such as a lower rate of Adenomatosis Polyposis Coli mutations and earlier p53 mutations, IBD-associated cancer has a similar dysplasia-cancer sequence to sporadic colon cancer, similar frequencies of major chromosomal abnormalities and of microsatellite instability and similar glycosylation changes. This suggests that IBD-associated colon cancer and sporadic colon cancer might have similar pathogenic mechanisms. Because the normal colon is arguably in a continual state of low-grade inflammation in response to its microbial flora, it is reasonable to suggest that both IBD-associated and sporadic colon cancer may be the consequence of bacteria-induced inflammation. We have speculated that the glycosylation changes might result in recruitment to the mucosa of bacterial and dietary lectins that might otherwise pass harmlessly though the gut lumen. These could then lead to increased inflammation and/or proliferation and thence to ulceration or cancer. The glycosylation changes include increased expression of onco-fetal carbohydrates, such as the galactose-terminated Thomsen-Friedenreich antigen (Gal beta1,3GalNAc alpha-), increased sialylation of terminal structures and reduced sulphation. These changes cannot readily be explained by alterations in glycosyltransferase activity but similar changes can be induced in vitro by alkalinisation of the Golgi lumen. Consequences of these changes may be relevant not only for cell-surface glycoconjugates but also for intracellular glycoconjugates.

Antigens, Tumor-Associated, Carbohydrate↗

Anti-cardiolipin and anti-beta2-glycoprotein I antibodies in patients with inflammatory bowel disease.

Patients with inflammatory bowel disease (IBD) frequently suffer from thromboembolic events. Anti-cardiolipin (aCL) antibodies have been shown to be associated with thrombosis. Recently, the antibodies against the anti-cardiolipin cofactor beta2-glycoprotein I (a(beta2)GPI) have been found with higher specificity for thrombosis. The presence of these antibodies was assessed in 128 patients with IBD [83 with ulcerative colitis (UC) and 45 with Crohn's disease (CD)] and 100 healthy controls (blood donors). Patients with UC and CD had a significantly higher prevalence of aCL (18.1% and 15.6%, respectively) than healthy controls (HC) (3%). Eleven IBD patients (8.6%) but no HC had a(beta2)GPI. None of the IBD patients with a history of thrombosis had aCL and only one of them (a UC patient with deep vein thrombosis of the right leg) had a high titer of IgG a(beta2)GPI. In conclusion, these data show that both aCL and a(beta2)GPI are significantly associated with IBD but further studies are needed to determine the significance of our findings.

Antibodies↗

Increased colonic ornithine decarboxylase activity in inflammatory bowel disease in children.

The risk of colorectal carcinoma is increased in pediatric-onset inflammatory bowel disease (IBD). There is little information available regarding the colonic mucosal proliferative state in children with IBD. The aim of this study was to assess colonic ornithine decarboxylase (ODC) activity, a marker of cell proliferation, in pediatric IBD patients. ODC activity was assessed in colonic mucosa from 23 children (7 with ulcerative colitis, 9 with Crohn's disease, and 7 controls) undergoing colonoscopic examination. ODC activities were then compared with degree of inflammation of biopsied samples. ODC activities in patients with and without corticosteroid treatment were also analyzed. The mucosal ODC activities of sigmoid colon and rectum were significantly higher (2.5- to 4-fold) in both ulcerative colitis and Crohn's disease. The higher ODC activity was associated with increased mucosal inflammation. Moreover, treatment with corticosteroids decreased the ODC activity. In conclusion, using ODC activities as a marker of cell proliferation, our results suggest that there is a higher colonic mucosal proliferative state in children with IBD. The increased ODC activities were associated with increased colonic mucosal inflammation. Colonic mucosal ODC activity may provide an additional parameter to access the therapeutic efficacy of corticosteroid treatment in pediatric IBD patients.

Adolescent↗

Role of microecology in chronic inflammatory bowel diseases.

Inflammatory bowel diseases (IBD) are chronic conditions of unknown etiology. Current therapy mitigates the severity of acute bouts of mucosal inflammation but an eradication therapy is lacking. Growing incidence of IBD is associated with social development. Epidemiology suggests a relationship between the establishment of the individual gut flora and the risk of developing IBD. Patients show an impaired tolerance towards commensal bacteria of the resident flora. Unrestrained activation of the intestinal immune system against some commensal bacteria appears to be responsible for the characteristic relapsing course of these diseases. Wide-spectrum antibiotic therapy reduces bacterial load and mitigates intestinal inflammation in human IBD and in animal models. Current research aims at the identification of probiotics for bacterial antagonism therapies. Probiotics are living microorganisms which upon ingestion in certain numbers exert health benefits beyond inherent basic nutrition. Colonization with a Lactobacillus reuteri strain can prevent the development of colitis in genetically susceptible mice. Other studies have used a bacterium genetically engineered to secrete the antiinflammatory cytokine IL-10 and demonstrated a therapeutic effect in animal models of colitis. Moreover, some probiotics may naturally exhibit antiinflammatory properties when interacting with the human gut mucosa. Prebiotics such as inulin have also been shown to prevent colonic inflammation in animal models. Preliminary clinical trials with probiotics in IBD are encouraging. Probiotics offer a valuable tool for the prevention and control of inflammatory bowel diseases.

Animals↗

Replication and extension studies of inflammatory bowel disease susceptibility regions confirm linkage to chromosome 6p (IBD3).

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the intestine, commonly diagnosed as either ulcerative colitis (UC) or Crohn's disease (CD). Epidemiological studies have consistently shown that both genetic and environmental factors influence the pathogenesis of IBD. A number of genome scans have been conducted in cohorts of IBD families with affected sibling pairs (ASPs) to identify chromosomal regions that harbour IBD susceptibility genes. Several putative linked loci have been identified, including two loci on chromosomes 16 and 12, IBD1 and IBD2, which have subsequently been replicated by independent region-specific studies. We have conducted both a replication study on another linkage region, chromosome 6p (IBD3), and extension studies on two other regions, chromosomes 3p and 7q. Microsatellite markers across each region were genotyped in 284 IBD ASPs from 234 families. A nonparametric peak multipoint LOD score of 3.0 was observed near D6S291, replicating the previous linkage to chromosome 6p (IBD3). Nominal evidence of linkage was observed at both the 3p and 7q regions.

Chromosome Mapping↗

Low prevalence of the APC I1307K sequence in Jewish and non-Jewish patients with inflammatory bowel disease.

A germline sequence alteration at codon 1307 of the APC gene (I1307K) has been reported in 6-7% of the Ashkenazi Jewish population in the United States. This alteration is believed to predispose the APC gene to a secondary mutation at the same locus, resulting in an increased risk of colorectal carcinoma. There is an increased risk of colorectal carcinoma in patients with inflammatory bowel disease (IBD), a relatively large proportion of whom are Ashkenazi Jews. We therefore sought to determine whether the I1307K sequence variant occurred in the germline DNA of IBD patients. To our surprise, we found this sequence in only two of 267 patients with IBD (0.7%), occurring in only 1.5% of Jewish IBD patients. The I1307K sequence variant was not found in 67 patients with esophageal cancer, 53 patients with gastric carcinoma (13 MSI-H and 44 MSI-negative), or ten patients with sporadic MSI-H colon cancer. These findings suggest that the I1307K sequence is relatively rare in the germline of Jewish as well as non-Jewish IBD patients. It does not appear to contribute to the increased colorectal cancer risk present in these patients.

Colorectal Neoplasms↗

Inflammatory bowel disease: pathogenesis and targets for therapeutic interventions.

Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases (IBDs) with a chronic relapsing course. The aetiology of these diseases remains unknown, but in the last decade an increase in experimental models of IBD has led to expansion of our understanding in various aspects of the aetiology and pathogenic mechanisms of IBD. A growing body of evidence coming from these models indicates that an immune response against gut constituents is of critical importance for intestinal inflammation and the subsequent destruction of the mucosa. For this reason, research on IBD has focused intensely on the immune and non-immune cell subsets as well as the soluble mediators involved in normal and dysregulated immune responses. An appreciation of the current knowledge of the pathogenesis of IBD is of paramount importance for the understanding of current, and development of new, treatment modalities.

Animals↗

Interleukin-1 and interleukin-1 receptor antagonist in inflammatory bowel disease.

Ulcerative colitis (UC) and Crohn's disease (CD) are immunologically mediated disorders characterized by a chronic, relapsing inflammatory response. Elevation of several cytokines, with important immunoregulatory and proinflammatory activities have been demonstrated during active inflammatory bowel disease (IBD). These cytokines, including interleukin-1 (IL-1), IL-6, IL-8 and GM-CSF, may play an important role in the initiation and amplification of the inflammatory response leading to intestinal injury. There is increasing evidence that IL-1 is activated early in the cascade of events leading to inflammation. Therefore, IL-1 has been implicated as a primary target for therapeutic intervention for the treatment of several inflammatory diseases, including IBD. In addition, a mucosal imbalance of intestinal IL-1 and IL-1ra is present in patients with IBD, suggesting that insufficient production of endogenous IL-1ra may contribute to the pathogenesis of chronic gut inflammation. Preliminary studies examining the association between newly described polymorphisms in the IL-1 gene cluster and IBD have provided new insight into the genetic predisposition to UC. This article will review current progress in understanding the role of Il-1 and Il-1ra in IBD, as well as discuss recently described polymorphisms in the Il-1 gene cluster and their association with UC and CD.

Animals↗

Evaluation of new therapies for inflammatory bowel disease.

The pathophysiology of inflammatory bowel disease (IBD) is gradually being unravelled and new therapies are being developed to target the disturbed biological processes. This article outlines the clinical features of IBD, its current therapy and pathogenesis. The difficulties for clinical pharmacologists and gastroenterologists associated with designing, executing and interpreting clinical trials in IBD are then discussed. The final section reviews methods that can used to demonstrate the pharmacological actions of new treatments in patients with IBD. It is emphasized that proof of the therapeutic efficacy of a novel agent with a specific mechanism of action yields not only clinical benefit to patients with IBD, but also indicates the importance of the targeted biochemical pathway in the pathogenesis of the disease.

Biopsy↗

CD4+ T lymphocytes injected into severe combined immunodeficient (SCID) mice lead to an inflammatory and lethal bowel disease.

Transfer of 2 x 10(5) congenic or semiallogenic purified TCR alphabeta+ CD4+ T cells to SCID mice leads to an infiltration of the recipient gut lamina propria and epithelium with a donor-derived CD4+ T cell subset which induces a lethal inflammatory bowel disease (IBD) in the recipients. In contrast, IBD was not observed in SCID mice transplanted with unfractionated splenic cells. The earliest detectable pathological changes after CD4+ T cell transfer were proliferation and hypertrophy of the entire colonic epithelial layer, including increased mitotic activity, increased expression of epithelial nuclear proliferation antigen, and elongation of the crypts. Later on, massive mononuclear cell infiltration, hypertrophy of all layers of the colon and occasional epithelial ulcerations were observed. At this stage, accumulations of IgA, IgM and small numbers of IgG1-, IgG2- and IgG3-secreting plasma cells were present in the lamina propria of both the small and large intestine. We conclude that low numbers of intraveneously transferred CD4+ T cells induce IBD in SCID mice. In the late stages of CD4+ T cell-induced IBD, the colonic lamina propria becomes infiltrated with macrophages, neutrophils and plasma cells secreting IgA, IgM, and to a lesser degree IgG antibodies which might play an accessory role in the pathogenesis of IBD.

Adoptive Transfer↗

MHC class I chain-like gene A (MICA) and its associations with inflammatory bowel disease and peripheral arthropathy.

MHC class I chain gene A (MICA) is a non-classical Class I gene which is expressed on the surface of epithelia without beta 2-microglobulin. The gene is found in the major histocompatibility complex (MHC) in tight linkage disequilibrium with human leucocyte antigen-B (HLA-B). Its precise function is unknown, but it interacts with gamma delta T cells of the intestinal immune system. This region of the MHC has been implicated in inflammatory bowel disease (IBD) pathogenesis by recent association mapping studies and this study was performed to examine the prevalence of MICA gene polymorphisms in IBD, in particular in type 2 peripheral arthropathy (PeA), which also has a strong HLA-B association. An assessment of the prevalence of MICA polymorphisms in IBD was made. Blood from 50 ulcerative colitis (UC) and 50 Crohn's disease controls was taken and MICA status determined using allele-specific PCR for 16 known alleles of MICA. A further 91 UC patients were recruited to confirm the results of this stage, and then the polymorphisms were studied in 52 type 1 and 45 type 2 PeA patients. The MICA status of these groups was compared with 118 blood and organ donor controls with appropriate correction for multiple comparisons. UC overall was associated with possession of MICA*007 in 32% compared to 11% of controls (P(c) = 0.017). This association was confirmed in a second cohort of 91 patients (23% versus 11%, P = 0.02). These were independent of HLA class I status. Type 2 IBD PeA was associated with MICA*008 in 98% compared to 73% of controls (P = 0.0001). MICA*007 is associated with susceptibility to UC in our population and MICA*008 with type 2 IBD PeA. Further work is now required to assess the distribution and expression of MICA throughout the gut in health and disease.

Case-Control Studies↗

Modulation of cytokine release from colonic explants by bacterial antigens in inflammatory bowel disease.

The intestinal flora play an important role in experimental colitis and inflammatory bowel disease (IBD). Using colonic explant cultures from 132 IBD and control subjects, we examined tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 and interleukin-1 receptor antagonist (IL-1RA) production in vitro in response to bacterial activators. Unstimulated TNF-alpha release was increased significantly in rectal biopsies from involved IBD tissue, correlating with inflammation severity. Whereas lipopolysaccharide (LPS) only moderately stimulated TNF-alpha production from inflamed tissue, pokeweed mitogen (PWM) induced its release in all groups, with a stronger response in involved IBD tissue. Superantigen staphylococcal enterotoxin A (SEA) had a similar, but weaker effect. SEB was observed to be the strongest inducer of TNF-alpha for all groups, again with a more marked response in inflamed tissue. Stimulated release of IL-1 was considerably less than for TNF-alpha. The superantigens' superior potency over LPS was not as marked for IL-1 as it was for TNF-alpha. In addition to IL-1, IL-1RA release was also triggered by the bacterial products. The net effect of activation on the IL-1RA/IL-1 ratio was relatively modest. Release of the proinflammatory cytokines TNF-alpha and IL-1, as well as that of the anti-inflammatory cytokine IL-1RA was increased by incubation of colonic tissue with bacterial factors. TNF-alpha production and release was increased significantly in involved colonic explants from IBD. SEB was even capable of inducing TNF-alpha release from uninvolved colonic tissue.

Adolescent↗

Bacteria-specific T-cell clones are selective in their reactivity towards different enterobacteria or H. pylori and increased in inflammatory bowel disease.

In the present study the authors investigated the T-cell response to different enterobacteria or Helicobacter pylori and tested the hypothesis that the frequency of bacteria-specific T cells is increased in the intestine of patients with active inflammatory bowel disease (IBD), i.e. Crohn's disease (CD) and ulcerative colitis (UC). The analysis of a large panel of T-cell clones (Tc) (n = 888) from peripheral blood, non-inflamed and inflamed intestine from IBD patients and control individuals shows that both peripheral blood and intestinal T-cell clones were selectively stimulated by either Salmonella typhimurium, Yersinia enterocolitica 03, Escherichia coli or Helicobacter pylori sonicates, that only < 3% of all bacteria-reactive Tc were crossreactive and that proliferation to bacterial sonicates was inhibited by anti-MHC class II antibody. In addition, bacteria-specific Tc from IBD patients were more frequently isolated from inflamed intestine than from peripheral blood (P = 0.0039) or non-inflamed intestine. These data, from a large number of T-cell clones, are the first systematic analysis describing the response of individual T cells towards different bacterial species (ssp.). They show that T cells with specificity for distinct antigens or superantigens that are characteristic for a defined bacteria ssp. are present in normal, and increased in inflamed, IBD-intestine. These bacteria-specific Tc may play a role in IBD pathogenesis.

Adult↗

A review of leukofiltration therapy for decreasing the morbidity associated with cardiopulmonary bypass and acute inflammatory bowel disease.

Complications of cardiopulmonary bypass (CPB) and acute inflammatory bowel disease (IBD) are associated with increased morbidity and cost. During reperfusion post-CPB, activated neutrophils adhere to microvascular endothelial cells mediated by cell adhesion molecules (CAMs) and cytokines/chemokines with subsequent myocardial damage caused by activated neutrophil-derived oxidants and enzymes. Leukofiltration was shown to reduce myocardial reperfusion injury and improve gas exchange as suggested by improvements in surrogate markers of inflammation and clinical end points. In acute IBD, characterized by rectal bleeding and protracted hospital stays, circulating neutrophils emigrate to the inflamed colon and adhere to microvascular endothelial cells by CAMs. Multiple treatments with leukofiltration in IBD were shown to induce long-term remission of acute IBD. Hence, leukofiltration may reduce reperfusion injury and rectal bleeding in CPB and IBD, respectively, and therefore decrease the morbidity and cost associated with these diseases.

Acute Disease↗

The present status and the recent development of the treatment for inflammatory bowel diseases: desirable effect of extracorporeal immunomodulation.

The immunological and genetic pathogeneses of inflammatory bowel disease (IBD) have been well elucidated in the recent years. The pharmacologic treatment of IBDs accordingly becomes to focus upon the individual pathologic step (targeting therapy), whereas the therapeutic action is not yet a pinpoint one. It has been known recently that new drugs such as biological immunomodulating agents and anti-inflammatory cytokines have better short-term effects in some respects than the conventional drugs, and they might alter the treatment strategy of IBDs in the near future. The limitation of pharmacologic treatments mainly results from adverse effects of the drugs, i.e. infection susceptibility, oncogenesis, teratogenesis and so forth. The extracorporeal therapy such as leukocytapheresis and photopheresis is reportedly effective for IBDs probably through immunomodulation such as decrease in circulating activated T-lymphocytes and activated granulocytes that play a central role in the pathogenesis of IBD. It can be said that these extracorporeal treatment methods have advantage of rapid action and lack of serious adverse effects to drug therapy.

Adjuvants, Immunologic↗

Inflammatory bowel disease in 67 families each with three or more affected first-degree relatives.

BACKGROUND & AIMS: Some families have multiple members with inflammatory bowel disease (IBD). Do clinical features of familial differ from sporadic cases? Is there concordance between affected family members? Do environmental factors affect familial clustering? METHODS: In 67 families, each with three or more first-degree relatives with IBD, the 213 affected family members were interviewed, and their case records were reviewed. RESULTS: The clinical manifestations of familial cases did not differ from IBD reported in a large series. There was concordance for type of disease (P < 0.001) but not greater than expected concordance for age at diagnosis, site and extent of disease, or transmural aggressiveness of Crohn's disease. A significant association between smoking with Crohn's disease and non-smoking with ulcerative colitis was found (P < 0.001), even in families with both disorders. The intervals between diagnosis of successive family cases varied so greatly that a single etiologic factor with a constant latent period seems to be unlikely. When IBD affected successive generations, parents were diagnosed at a later age than the children (P < 0.001) and after the child in 12 of 49 cases. CONCLUSIONS: Analysis has not identified any clinically significant differences between familial and sporadic cases of IBD. Tobacco smoking affects disease type in familial cases.

Adolescent↗