Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In both Crohn's disease (CD) and ulcerative colitis, the pathologic process is almost certainly driven by an aberrant local immune response directed against normal components of the bacterial microflora. Mucosal immune cells interact with nonimmune cells such as epithelial cells and fibroblasts to promote tissue damage; cytokines are essential mediators of this cross talk. Accumulating evidence now suggests that interleukin-21 (IL-21), the newest member of the common gamma-chain-dependent cytokine family, is a key component of the inflammatory cascade. IL-21 is highly produced by activated CD4+ lymphocytes in the inflamed gut of patients with CD, where it contributes to sustaining the ongoing Th1 inflammation. IL-21 also increases the secretion of extracellular matrix-degrading enzymes by fibroblasts and of MIP-3alpha by epithelial cells. Two other cytokines, IL-27 and IL-32, may also be important in the inflammatory pathways that operate in IBD.
 ...
PMID:New players in the cytokine orchestra of inflammatory bowel disease. 1771 36

The objectives of the present study were to evaluate the presence of antipolymer antibody (APA) seropositivity in 285 Italian patients affected by primary fibromyalgia (FM) and to verify whether APA levels correlate with disease severity and with cytokine levels.APA levels were determined on serum samples by an indirect ELISA kit that detects IgG APA. Cytokines (IL-1, IL-6, IL-8, IL-10 and TNFalpha) were measured by ELISA in plasma. The impact of FM on the quality of life was estimated using the Fibromyalgia Impact Questionnaire, while pain severity was evaluated using a visual analogic scale. Patients were also characterized by the presence of tiredness, stiffness, nonrestorative sleep, anxiety, depression, tension headache, irritable bowel syndrome, temporomandibular dysfunction and Raynaud's phenomena. Using a cut-off value of 30 U, APA-positive values were detected in 60 FM patients (21.05%) and in 15 healthy control individuals (15.00%) without significant differences among their levels or the percentage of seropositivity. FM patients with moderate and severe symptoms had slightly higher APA levels with respect to patients with mild symptoms. APA-seropositive patients exhibited significant correlations between APA levels and the Fibromyalgia Impact Questionnaire estimate (P = 0.042), tiredness (P = 0.003) and IL-1 levels (P = 0.0072). In conclusion, APA cannot be considered a marker of disease in Italian FM patients. The presence of APA, however, might permit the identification of a subset of FM patients with more severe symptoms and of patients who may respond differently to different therapeutic strategies.
 ...
PMID:Antipolymer antibody in Italian fibromyalgic patients. 1782 28

The mechanisms leading to positive effects of probiotics in irritable bowel syndrome and inflammatory bowel disease have not been clarified, but the possible involvement of cell wall components is widely discussed. Reduction of the D-alanine content of lipoteichoic acid (LTA) in Lactobacillus plantarum (Dlt(-) mutant) enhanced its anti-inflammatory properties in a mouse colitis model. Another lactobacillus species inhibited visceral pain perception in response to colorectal distension (CRD) in rats. Therefore, we investigated if LTA modification influences the constitutive intestinal pain perception in addition to modulation of cytokine release. Male Sprague-Dawley rats were gavaged with L. plantarum, L. plantarum Dlt(-) mutant or buffer control, respectively and the responses to CRD were tested in this non-inflammatory model. Tumour necrosis factor (TNF), interferon (IFN)-gamma and interleukin (IL)-10 release were measured in colon tissue homogenates and upon anti-CD3/CD28 activation of isolated splenocytes and mesenteric lymphocytes. Control animals showed significant bradycardia following noxious CRD, whereas only the L. plantarum Dlt(-) mutant inhibited the response. The mutant also decreased the activation-induced release of TNF and IFN-gamma from mesenteric T cells and the IL-10 concentration in colonic tissue, while increasing the activation-induced secretion of IL-10 in splenocytes and mesenteric lymphocytes and the baseline IL-10 release of splenocytes. In conclusion, d-alanine depletion of LTA in L. plantarum inhibited visceral pain perception in healthy, non-inflamed rats. Regardless of the non-inflammatory nature of the model decreased visceral pain perception was seen in parallel with anti-inflammatory properties.
 ...
PMID:The D-alanine content of lipoteichoic acid is crucial for Lactobacillus plantarum-mediated protection from visceral pain perception in a rat colorectal distension model. 1831 44

The pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) plays a central role in mucosal inflammation and is a key mediator in the inflammatory cascade in both Crohn's disease (CD) and ulcerative colitis (UC). Infliximab, a monoclonal antibody against TNF-alpha has been proved highly effective in the clinical management of both forms of IBD. Aim of this paper is to review the mechanisms of action of infliximab in IBD.
 ...
PMID:Mechanisms of action of infliximab in inflammatory bowel disease: an anti-inflammatory multitasker. 1859 93

Enhanced stress responsiveness has been implicated as a potential mechanism contributing to the pathophysiology of irritable bowel syndrome (IBS), and should be reflected in altered function of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system. Both of these systems can modulate mucosal immune function. The aims of this study were: (i) to characterize the basal circadian rhythm of adrenocorticotropin hormone (ACTH) and cortisol in IBS vs healthy controls; (ii) to compare stimulated ACTH, cortisol and noradrenaline responses to a pelvic visceral stressor (sigmoidoscopy) in IBS and controls; and (iii) to correlate neuroendocrine responses with colonic mucosal cytokine expression and symptoms in IBS. Two separate studies were conducted in women. In Study 1, basal cortisol levels were analysed in 41 IBS and 25 controls using 24-h collections of plasma ACTH and cortisol (q10 min sampling). In Study 2, 10 IBS patients with diarrhoea (IBS-D) and 10 controls underwent sigmoidoscopy with measurements of stimulated neuroendocrine responses and cytokine mRNA expression in colonic tissue. Basal ACTH levels were significantly blunted (P < 0.05), while basal and stimulated plasma cortisol levels were higher in patients. Basal cortisol levels prior to an experimental visceral stressor positively correlated with anxiety symptoms (P < 0.004), but not IBS symptoms. Irritable bowel syndrome patients with diarrhoea had significantly decreased mRNA expression of mucosal cytokines [interleukin (IL)-2, IL-6] in the sigmoid colon vs controls (P < 0.05). Although dysregulations in stress-responsive systems such as the HPA axis and mucosal immune function are demonstrated in IBS, they do not appear to have a primary role in modulating IBS severity and abdominal pain.
 ...
PMID:Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in irritable bowel syndrome. 1868 12

There is increasing evidence for involvement of the immune system in functional gastrointestinal disorder (FGID), including onset after acute gastrointestinal infections, genotypes resulting in altered cytokine expression and abnormal presence of immune cells. Our aim was to assess cellular and humoral immune responses in (i) FGIDs, compared to healthy subjects and (ii) acute vs unspecified onset FGIDs. Lymphocytic [interleukin (IL)-5, IL-10, IL-13 and interferon gamma (IFN-gamma)] and monocytic [IL-10, IL-12, tumour necrosis factor (TNF)-alpha] cytokine production was characterized at baseline and after stimulation with phytohemagglutinine and anti-CD28 or lipopolysaccharide (LPS) in controls (n = 32), irritable bowel syndrome (IBS) (n = 30), functional dyspepsia (FD) (n = 23) and non-cardiac chest pain (NCCP) (n = 15). Serum IL-6 and IL-10 concentrations were compared, and the immunophenotype was assessed using fluorescent-activated cell sorter. Findings were compared for acute vs unspecified onset FGID. Compared to controls, stimulated lymphocyte expression of IL-5 and IL-13 was enhanced in IBS, FD and NCCP (all P < 0.05). Conversely, the stimulated monocytic IL-12 and lymphocytic IL-10 expression were reduced in IBS and FD, while IFN-gamma expression was also reduced in FD patients. Except for an increase in the numbers of CD3(+)CD45RA(+)CD45RO(+) cells, no distinct cellular profile was detected. Patients with a presumed acute onset of their symptoms had higher serum IL-10 levels and more CD3(+)CD45RA(+)CD45RO(+) cells, while TNF-alpha levels following stimulation with LPS were higher in FD patients reporting an acute onset. A shift towards a Th2 cytokine profile is present in FGID, while the cellular immunophenotype remains largely unchanged. Further research is indicated and could provide new therapeutic strategies for these disorders.
 ...
PMID:Immune dysfunction in patients with functional gastrointestinal disorders. 1912 84

Anti-inflammatory and anti-nociceptive properties of endocannabinoids and synthetic cannabinoid compounds were described previously. We studied effects of the endogenous cannabinoid anandamide (N-arachidonylethanolamine) in experimental colitis induced by TNBS (2,4,6-trinitrobenzene sulfonic acid) in AKR mice. A scoring system was used to describe clinical and macroscopic changes. Intraperitoneally administered anandamide significantly reduced experimental colitis, quantified by macroscopical and histological scoring systems as well as pro-inflammatory cytokine mRNA expression. We conclude that systemically administered anandamide attenuates TNBS colitis in mice, and that systemically active cannabinoid compounds might have therapeutic potential for the treatment of IBD.
 ...
PMID:Ulcerative colitis in AKR mice is attenuated by intraperitoneally administered anandamide. 1921 3

The epithelium in inflamed intestinal segments of patients with Crohn's disease is characterized by a reduction of tight junction strands, strand breaks, and alterations of tight junction protein content and composition. In ulcerative colitis, epithelial leaks appear early due to micro-erosions resulting from upregulated epithelial apoptosis and in addition to a prominent increase of claudin-2. Th1-cytokine effects by interferon-gamma in combination with TNFalpha are important for epithelial damage in Crohn's disease, while interleukin-13 (IL-13) is the key effector cytokine in ulcerative colitis stimulating apoptosis and upregulation of claudin-2 expression. Focal lesions caused by apoptotic epithelial cells contribute to barrier disturbance in IBD by their own conductivity and by confluence toward apoptotic foci or erosions. Another type of intestinal barrier defect can arise from alpha-hemolysin harboring E. coli strains among the physiological flora, which can gain pathologic relevance in combination with proinflammatory cytokines under inflammatory conditions. On the other hand, intestinal barrier impairment can also result from transcellular antigen translocation via an initial endocytotic uptake into early endosomes, and this is intensified by proinflammatory cytokines as interferon-gamma and may thus play a relevant role in the onset of IBD. Taken together, barrier defects contribute to diarrhea by a leak flux mechanism (e.g., in IBD) and can cause mucosal inflammation by luminal antigen uptake. Immune regulation of epithelial functions by cytokines may cause barrier dysfunction not only by tight junction impairments but also by apoptotic leaks, transcytotic mechanisms, and mucosal gross lesions.
 ...
PMID:Epithelial tight junctions in intestinal inflammation. 1953 19

Symptoms consistent with the irritable bowel syndrome are remarkably frequent around the world. Irritable bowel syndrome prevalence ranges from 2.1% to 22%, depending on criteria used. Women are more frequently affected than men, but the reasons remain obscure; irritable bowel syndrome occurs in all age groups but there appears to be a modest decline in prevalence with advancing age again for unknown reasons. The incidence of irritable bowel syndrome per year has been estimated at approximately 1.5% in community subjects; annually only 0.2% of population will be diagnosed with irritable bowel syndrome. The natural history of irritable bowel syndrome is characterized by symptomatic flare ups and by a high rate of transition to other functional gastrointestinal diseases over the long term. Well recognized risk factors for irritable bowel syndrome include psychological distress and gastroenteritis. However, the association of psychological distress in some cases may reflect confounding factors and might be explained at least in part by cytokine production. Familial aggregation of irritable bowel syndrome occurs, and while the environment is key, twin studies generally support a genetic component in irritable bowel syndrome explaining up to 20% of the variability. Prior surgery may increase risk of irritable bowel syndrome. Early childhood trauma may be important; a low birth weight, nasogastric suction at birth, childhood abuse, and low socioeconomic status may carry an increased risk of suffering with irritable bowel syndrome as an adult. The role of diet remains uncertain but under-studied.
 ...
PMID:Irritable bowel syndrome: novel views on the epidemiology and potential risk factors. 1966 52

Hyperactivation and hyperpermeability of the intestinal epithelium is a hallmark of IBD. AM has been shown to reduce the severity of colitis in the acetic acid and TNBS-induced colitis model, however the mechanism of the therapeutic effect of AM against the colitis has not been clarified. Here, we show that the protective capability of AM is associated with suppression of inflammation and maintenance of the intestinal epithelial barrier function. In the DSS-induced colitis model, intra-rectal AM-treated mice showed a reduction in loss of body weight and severity of colitis. AM-treatment suppressed phosphorylation of STAT1 and STAT3 in the colonic epithelium, and altered the cytokine balance in the intestinal T cells, with lower levels of IFN-gamma and TNF-alpha but higher levels of TGF-beta. Expression of the epithelial intercellular junctions such as tight and adherence junctions were sustained in the AM-treated mice. In contrast, the epithelial junctions were down-regulated in the control mice, leading to loss of epithelial barrier integrity and enhanced permeability. Collectively, these data indicate a broad spectrum of AM-induced effects with respect to protection against DSS-induced colitis, and suggest a potential therapeutic value of this treatment for IBD.
 ...
PMID:Adrenomedullin treatment reduces intestinal inflammation and maintains epithelial barrier function in mice administered dextran sulphate sodium. 1978 Sep 71


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>