Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0010346 (Crohn's disease)
 21,615 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Circulating proinflammatory cytokines may be involved in osteopenia associated with Crohn's disease (CD). Therefore, the effect of interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF) a contained in Crohn's serum on bone formation was examined in a bone organ culture system. Initially, serum levels of IL-6, IL-1beta, and TNF-a were determined by ELISA in newly diagnosed, untreated children with CD and healthy age-matched controls. Serum IL-6 levels were significantly higher in patients with CD than in controls (23.9 +/- 2.8 pg/ml vs. 0.7 pg/ml +/- 0.2; p < 0.001), whereas IL-1beta and TNF-alpha serum levels were not. In the organ culture studies, 20-day-old fetal rat parietal bones were incubated for 96 h with CD or control serum, serum preincubated with a neutralizing antibody to each cytokine or a nonimmune immunoglobulin control, and with IL-6. Bone formation measured by assaying calcium content and dry weight was significantly decreased in bones exposed to Crohn's serum. Light microscopy of the bones treated with CD serum revealed a discontinuous, uneven mineralized bone matrix and disorganized osteoblasts with altered morphology. Incubation with an antibody that neutralized IL-6 activity prevented the change in osteoblast and bone morphology. TNF-a and IL-1beta antibodies had no apparent effects. Collagen synthesis and DNA content were not affected by CD serum. Also, addition of IL-6 to the culture medium decreased mineralization. These results suggest that IL-6 is a mediator of the effects of Crohn's serum on in vitro mineralization and may be a contributing factor to the osteopenia associated with CD.
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PMID:Effect of Crohn's disease on bone metabolism in vitro: a role for interleukin-6. 1191 27

Inflammatory bowel diseases (IBD)--Crohn's disease and ulcerative colitis--are relapsing chronic inflammatory disorders which involve genetic, immunological, and environmental factors. The regulation of TNF-alpha, a key mediator in the inflammatory process in IBD, is interconnected with mitogen-activated protein kinase pathways. The aim of this study was to characterize the activity and expression of the four p38 subtypes (p38alpha-delta), c-Jun N-terminal kinases (JNKs), and the extracellular signal-regulated kinases (ERK)1/2 in the inflamed intestinal mucosa. Western blot analysis revealed that p38alpha, JNKs, and ERK1/2 were significantly activated in IBD, with p38alpha showing the most pronounced increase in kinase activity. Protein expression of p38 and JNK was only moderately altered in IBD patients compared with normal controls, whereas ERK1/2 protein was significantly down-regulated. Immunohistochemical analysis of inflamed mucosal biopsies localized the main expression of p38alpha to lamina propria macrophages and neutrophils. ELISA screening of the supernatants of Crohn's disease mucosal biopsy cultures showed that incubation with the p38 inhibitor SB 203580 significantly reduced secretion of TNF-alpha. In vivo inhibition of TNF-alpha by a single infusion of anti-TNF-alpha Ab (infliximab) resulted in a highly significant transient increase of p38alpha activity during the first 48 h after infusion. A significant infliximab-dependent p38alpha activation was also observed in THP-1 myelomonocytic cells. In human monocytes, infliximab enhanced TNF-alpha gene expression, which could be inhibited by SB 203580. In conclusion, p38alpha signaling is involved in the pathophysiology of IBD.
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PMID:p38 mitogen-activated protein kinase is activated and linked to TNF-alpha signaling in inflammatory bowel disease. 1199 93

Adalimumab (D2E7), a human monoclonal antibody that binds to and neutralizes TNFa, is being developed by Abbott (formerly Knoll), under license from Cambridge Antibody Technology (CAT), for the potential treatment of inflammatory disorders such as rheumatoid arthritis (RA) and Crohn's disease. It is also being investigated for the potential treatment of coronary heart disease. Phase II studies for Crohn's disease and phase III for RA were ongoing throughout 2001. Limited data are only available for RA. In January 2002, it was reported that phase III trials of adalimumab for RA had been completed, but details have not been published in the primary literature so far. At this time CAT and Abbott expected to file for US approval in the second quarter of 2002 with a launch date anticipated for 2003. Phase III data are expected to be presented at the European League Against Rheumatism meeting in June 2002. In November 2000, Lehman Brothers predicted a US launch in June 2002 with peak US sales of $600 million in 2007 and a launch in non-US markets in 2003 with peak sales in these markets of $300 million in 2008. In December 2000, Merrill Lynch predicted regulatory clearance in the second half of 2003. The probability of adalimumab reaching the market is estimated to be 70%. In December 2000, Merrill Lynch predicted a 2003 launch, with estimated sales of pounds sterling 3.65 million in that year rising to pounds sterling 30.14 million in 2010. In March 2001, ABN AMRO predicted sales of $73 million in 2003 rising to $392 million in 2007.
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PMID:Technology evaluation: adalimumab, Abbott laboratories. 1204 41

Crohn's disease is characterized by a chronic inflammation of the intestine of unknown aetiology. One of the main problems when treating patients with Crohn's disease, is the identification of patients undergoing early clinical relapse, for timely treatment and the possible prevention of complications. No sub-clinical markers are currently available that predict relapse during remission. Several parameters have been proposed for this purpose. Although none have proven useful, growing evidence suggests a possible benefit in the clinical management of Crohn's disease. Among these, we may identify: clinical behaviour, the characteristics of the host, clinical activity, markers of intestinal inflammation and markers of immune activation. In particular, the possible relationship between cytokine pattern and the clinical behaviour of Crohn's disease has been addressed. Overall, these observations suggest that mucosal immune activation is a feature of Crohn's disease, and may persist in the form of activated immunocompetent cells during remission. On the basis of this evidence, studies are currently investigating whether the down-regulation of immune activation markers is associated with clinical remission in Crohn's disease. It has been shown that higher mucosal levels of TNF-alpha and an increased state of activation of lamina propria mononuclear cells in patients with inactive Crohn's disease, are significantly associated with an earlier clinical relapse of the disease. These observations suggest that a persistent local immune activation during remission may represent a marker of early clinical relapse of Crohn's disease.
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PMID:Review article: monitoring the activity of Crohn's disease. 1204 57

Infliximab (anti-TNF-alpha monoclonal antibody) induces remission in 30-40% of Crohn's disease patients. Treatment response is a stable trait. Two cohorts from independent, prospective clinical trials of infliximab in Crohn's disease were studied. Hypotheses were generated in an exploratory cohort (n = 90) and then tested in a confirmatory cohort (n = 444), using a statistical design, which is stable against type 1 and type 2 errors. In the exploratory cohort, the mutant 196Arg allele of TNFR-II (exon 6 polymorphism) and a novel silent polymorphism in exon 2 of TNFR-II were associated with lack of response to infliximab (83.3% in homozygote mutant 196 Arg patients vs 36.9% in heterozygotes and wild-type homozygotes (P = 0.036) and 85.7% in homozygote mutant exon 2 patients vs 36.1% (P = 0.01), respectively). None of the homozygote mutant individuals (0/6) achieved clinical remission, whereas the remission rate was 35.7% (30/84) in wild-type homozygotes and heterozygotes. In the large second cohort, the observed genotype-phenotype associations were not replicated. Other polymorphisms (TNF-alpha promoter -238, -308, -376, -857, -1031, TNF-R-I -609, +36 (exon 1), TNF-R-II 1663, 1690 (3'-UTR)) were not associated with treatment response in both cohorts (P > 0.5). None of the polymorphisms was associated with refractory Crohn's disease itself when compared to healthy controls. In a two-cohort study, a series of polymorphisms in the TNF, the TNF-R-I and in the TNF-R-II genes could be thoroughly excluded as pharmacogenetic markers for a treatment response to infliximab and as etiologic factors for Crohn's disease, respectively. The discrepancy between the two cohorts observed for the TNF-R-II exon 6 and exon 2 polymorphism may point to a weak effect on treatment response but also serves to illustrate the need for a sequential exploratory/confirmatory design in pharmacogenetic studies.
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PMID:Pharmacogenetic investigation of the TNF/TNF-receptor system in patients with chronic active Crohn's disease treated with infliximab. 1204 75

To clarify the role of IL-15 at local sites, we engineered a transgenic (Tg) mouse (T3(b)-IL-15 Tg) to overexpress human IL-15 preferentially in intestinal epithelial cells by the use of T3(b)-promoter. Although IL-15 was expressed in the entire small intestine (SI) and large intestines of the Tg mice, localized inflammation developed in the proximal SI only. Histopathologic study revealed reduced villus length, marked infiltration of lymphocytes, and vacuolar degeneration of the villus epithelium, beginning at approximately 3-4 mo of age. The numbers of CD8(+) T cells, especially CD8alphabeta(+) T cells expressing NK1.1, were dramatically increased in the lamina propria of the involved SI. The severity of inflammation corresponded to increased numbers of CD8alphabeta(+)NK1.1(+) T cells and levels of production of the Th1-type cytokines IFN-gamma and TNF-alpha. Locally overexpressed IL-15 was accompanied by increased resistance of CD8alphabeta(+) NK1.1(+) T cells to activation-induced cell death. Our results suggest that chronic inflammation in the SI in this murine model is mediated by dysregulation of epithelial cell-derived IL-15. The model may contribute to understanding the role of CD8(+) T cells in human Crohn's disease involving the SI.
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PMID:IL-15-dependent activation-induced cell death-resistant Th1 type CD8 alpha beta+NK1.1+ T cells for the development of small intestinal inflammation. 1207 77

Crohn's disease is a chronic inflammatory bowel disease of unknown aetiology which affects around 35,000 people in the UK (population 56.8 million). The potential for onset in early adult life, disease chronicity and a need for hospitalisation and surgery mean that the disease can be associated with substantial healthcare costs. Cost-of-illness studies focusing on direct medical costs have identified that over half the average costs associated with the disease relate to hospital costs. Estimates of the contribution of drug costs to the total direct economic burden have varied between 4.6 and 25%. Figures for average annual direct costs per patient in the US have been put at between US dollars 6561 (1990 values) and US dollars 12,417 (1994 values), whereas European studies have given much lower cost estimates (US dollars 655, 1994 values). However, all studies have highlighted that much of the total cost of illness relates to extensive interventions required by a small proportion of severely affected individuals. Indirect costs associated with reduced productivity in Crohn's disease can be high, with long periods of absenteeism and early disability. However, most patients (90%) remain in the workforce and life expectancy is relatively normal. A variety of drugs are employed for the treatment of Crohn's disease, both in an attempt to induce clinical remission in active disease and to maintain remission once this has been achieved. Comparative data on cost effectiveness is lacking, though crude estimates based on randomised trials suggest that the frequently prescribed aminosalicylates, which have only modest efficacy, are a relatively costly drug option. The costs associated with adverse drug effects, particularly for corticosteroids, have not been formally quantified. Despite high costs, new drug therapies for more severe disease, such as anti-tumour necrosis factor (TNF-alpha) antibodies, may prove a cost-effective option if the need for hospitalisation is reduced. In a modelling exercise, a US group estimated that if a theoretical new drug was introduced which was capable of reducing non-drug costs (including hospitalisation) by a fifth despite doubling the overall drugs bill, there would still be a reduction in the overall costs of Crohn's disease by 13%. Although surgical therapy is costly, there may be prolonged post-surgical remission following resection of localised disease and early surgery may represent a cost-effective option for selected patients. Without formal cost-effectiveness analyses, or (better still) clinical trials incorporating cost data, decisions about the relative efficiency of treatment alternatives for Crohn's disease remain subjective and more research is clearly required in this area.
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PMID:Cost of illness of Crohn's disease. 1216 53

The roles of various cytokines in early-phase mycobacterial infection were investigated utilizing murine tuberculosis models. Among them, IFN-gamma and TNF-alpha are very important in protective immunity against mycobacterial infection. This finding is closely associated with human tuberculosis. It is reported that persons with IFN-gamma receptor 1 deficiency and patients with rheumatoid arthritis and Crohn's disease are susceptible to Mycobacterium tuberculosis. It is expected that a novel immunotherapy and a diagnostic method of tuberculosis are developed by clarifying roles of various cytokines immunologically in early-phase mycobacterial infection.
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PMID:Study on the roles of cytokines involved in mycobacterial infection. 1223 51

Growth failure is common in children with inflammatory bowel disease (IBD) and has been attributed chiefly to undernutrition. Liquid enteral feeding can reverse the calorie deficit and increase growth velocity. The inflammatory process per se may also directly inhibit linear growth. After institution of enteral nutrition, significant changes in serum growth factors and inflammatory indices have been observed before any changes in nutritional parameters [Bannerjee et al., Gastroenterology 2000;118:A526]. In rats with trinitrobenzenesulphonic acid (TNBS)-induced colitis, about 60% of the final growth impairment can be attributed to undernutrition, inflammation accounting for the remaining growth deficit. Young patients with Crohn's disease and growth failure have normal stimulated and spontaneous growth hormone (GH) secretion and reduced plasma concentrations of insulin-like growth factor-1 (IGF-I), suggesting a degree of GH resistance. Rats with TNBS colitis also have normal plasma GH and reduced IGF-I concentrations, mediated by a combination of undernutrition and active inflammation. Immunoneutralization of interleukin-6 (IL-6) increases hepatic IGF-I mRNA expression, plasma concentrations of IGF-I and linear growth. In contrast, administration of anti-tumour necrosis factor-alpha antibodies (TNF-ab) had no effect on IGF-I in this model. TNFab did, however, increase linear growth, suggesting inhibitory effects of TNF-alpha on the growth axis by mechanisms other than reduction in IGF-I. Preliminary data suggests that TNF-alpha inhibits maturation of growth plate chondrocytes. We have identified IL-6 receptors on growth plate chondrocytes but to date have not identified the effect, if any, of IL-6 directly at the growth plate.
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PMID:Fundamental mechanisms of growth failure in inflammatory bowel disease. 1237 6

The key role and contribution of various pro-inflammatory cytokines in common chronic inflammatory disorders such as inflammatory bowel disease (IBD) has been thoroughly investigated in recent years. Besides IL-1, TNF-alpha has been identified as one of the central immune mediators controlling inflammatory processes. Not surprisingly, neutralisation of these cytokines has been introduced into clinical research. Crohn's disease (CD) is one of the chronic inflammatory disorders where TNF-alpha seems to have a particularly important role. Neutralisation of this cytokine by specific antibodies, for example infliximab, has been shown recently to affect the clinical phenotype of this disorder. Other TNF-neutralising approaches such as etanercept have also been studied in patients with CD but with less successful outcomes. These new cytokine-targeting approaches have changed clinical medicine in the field of inflammatory disorders.
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PMID:Antitumour necrosis factor therapy in Crohn's disease. 1238 70


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