Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The concept of spondylarthropathy (SpA) gathers together a group of chronic diseases with common clinical, biological, genetic and therapeutic characteristics. The concept forms a distinct entity, different from other rheumatic diseases. The target organs are not only the joint, but also the axial skeleton, the enthesis, the eye, the gut, the urogenital tract, the skin and sometimes the heart. The prevalence of this entity in the general population is estimated 1%, equal to the prevalence of rheumatoid arthritis. Genetical predisposition (HLA-B27) is one of the clues to the pathogenesis of the disease. Since reactive arthritis is induced by specific urogenital or enterogenic bacteria, and since the gut is implied in different forms of spondylarthropathies, especially in IBD, it was clear that the gut could play an important role by permitting exogenous factors to enter the body. This hypothesis was the rationale for investigating the gut in the spondylarthropathies by performing ileo-colonoscopies. In the first ileo-colonoscopic studies of SpA patients, histological signs of gut inflammation were found in a relatively great number of patients, mostly not presenting any clinical intestinal manifestations. These lesions were not seen in other inflammatory joint diseases. Further ileo-colonoscopic studies confirmed the strong relationship between gut and joint inflammation. In patients in whom a second ileo-colonoscopy was performed, remission of the joint inflammation was always connected with a disappearance of the gut inflammation, whereas persistence of locomotor inflammation was mostly associated to the persistence of gut inflammation. The hypothesis was proposed that some patients with a spondylarthropathy had a form of subclinical Crohn's disease in which the locomotor inflammation was the only clinical expression. This hypothesis was confirmed in prospective long-term studies in which the ileo-colonoscopied patients were reviewed 2 to 9 years later:about 6% of SpA patients not presenting any sign of Crohn's disease at first investigation but demonstrating gut inflammation on biopsy, developed full-blown Crohn's disease. By performing electronmicroscopy it was described that in patients with SpA the number of membranous (M) cells, which are scarce in normal ileum, is increased in number in inflamed mucosa. They showed a thin rim of cytoplasm covering groups of lymphocytes. In chronic inflammatory lesions necrotic M-cells, rupture of M-cells and lymphocytes entering the gut lumen was observed. The bursting of M-cells at the top of the lymphoid follicles leads to interruption of the gut epithelial lining and gives the luminal content access to the lymphoid tissue. This can be responsible for an exponential increase of local antigen stimulation. Accelerated luminal antigen presentation through a break in the epithelial layer, together with cytokines released from activated monocytes, might induce a second line of defense aiming at elimination of the massive antigen penetration into the mucosa. The postulated switch from secretory local immunity to a systemic type of local immune reaction could have different consequences:the local down-regulation of J chain in the IgA immunocytes could shift the production of polymeric IgA to monomers, jeopardizing secretory immunity; the disproportionate increase of IgG-producing cells could favor further inflammation and tissue damage through complement activation and arming of the killer cells, and cause autoimmune responses locally and in target organs at a distance (e.g. joint organs). The discovery of subclinical gut inflammation in the SpA had therapeutic consequences. Sulphasalazine (SASP) has been proven to be an active drug in the treatment of IBD. Since the gut could play a crucial role in SpA, it was logic to use this drug in the treatment of this disease. Multiple open and double-blind studies have proven the effectiveness of this drug in SpA.
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PMID:[Significance of intestinal inflammation in the pathogenesis of spondylarthropathies]. 876 79

Evidence for VIP influences on immune function comes from studies demonstrating VIP-ir nerves in lymphoid organs in intimate anatomical association with elements of the immune system, the presence of high-affinity receptors for VIP, and functional studies where VIP influences a variety of immune responses. Anatomical studies that examine the relationship between VIP-containing nerves and subpopulations of immune effector cells provide evidence for potential target cells. Additionally, the presence of VIP in cells of the immune system that also possess VIP receptors implies an autocrine function for VIP. The functional significance of VIP effects on the immune system lies in its ability to help coordinate a complex array of cellular and subcellular events, including events that occur in lymphoid compartments, and in musculature and intramural blood circulation. Clearly, from the work described in this chapter, the modulatory role of VIP in immune regulation is not well understood. The pathways through which VIP can exert an immunoregulatory role are complex and highly sensitive to physiological conditions, emphasizing the importance of in vivo studies. Intracellular events following activation of VIP receptors also are not well elucidated. There is additional evidence to suggest that some of the effects of VIP on cells of the immune system are not mediated through binding of VIP to its receptor. Despite our lack of knowledge regarding VIP immune regulation, the evidence is overwhelming that VIP can interact directly with lymphocytes and accessory cells, resulting in most cases, but not always in cAMP generation within these cells, and a subsequent cascade of intracellular events that alter effector cell function. VIP appears to modulate maturation of specific populations of effector cells, T cell recognition, antibody production, and homing capabilities. These effects of VIP are tissue-specific and are probably dependent on the resident cell populations within the lymphoid tissue and the surrounding microenvironment. Different microenvironments within the same lymphoid tissue may influence the modulatory role of VIP also. Effects of VIP on immune function may result from indirect effects on secretory cells, endothelial cells, and smooth muscle cells in blood vessels, ducts, and respiratory airways. Influences of VIP on immune function also may vary depending on the presence of other signal molecules, such that VIP alone will have no effect on a target cell by itself, but may greatly potentiate or inhibit the effects of other hormones, transmitters, or cytokines. The activational state of target cells may influence VIP receptor expression in these cells, and therefore, may determine whether VIP can influence target cell activity. Several reports described in this chapter also indicate that VIP contained in neural compartments is involved in the pathophysiology of several disease states in the gut and lung. Release of inflammatory mediators by cells of the immune system may destroy VIP-containing nerves in inflammatory bowel disease and in asthma. Loss of VIPergic nerves in these disease states appears to further exacerbate the inflammatory response. These studies indicate that altered VIP concentration can have significant consequences in terms of health and disease. In addition, the protective effects of VIP from tissue damage associated with inflammatory processes described in the lung also may be applicable to other pathological conditions such as rheumatoid arthritis, anaphylaxis, and the swelling and edema seen in the brain following head trauma. While VIP degrades rapidly, synthetic VIP-like drugs may be developed that interact with VIP receptors and have similar protective effects. Synthetic VIP-like agents also may be useful in treating neuroendocrine disorders associated with dysregulation of the hypothalamic-pituitary-adrenal axis, and pituitary release of prolactin.
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PMID:The significance of vasoactive intestinal polypeptide (VIP) in immunomodulation. 879 Jul 78

The concept of spondyloarthropathy (SpA) gathers together a group of chronic diseases with common clinical, biological, genetic and therapeutic characteristics. The concept forms a distinct entity, different from other rheumatic diseases. The target organs are not only the joint, but also the axial skeleton, the enthesis, the eye, the gut, urogenital tract, the skin and sometimes the heart. The prevalence of this entity in the general population is estimated 1%, equal to the prevalence of rheumatoid arthritis. Genetical predisposition (HLA-B27) is one of the clues to the pathogenesis of the disease. Since reactive arthritis is induced by specific urogenital or enterogenic bacteriae, and since the gut is implicated in different forms of spondyloarthropathies, especially in IBD, it was clear that the gut could play an important role by permitting exogenous factors to enter the body. This hypothesis was the rationale for investigating the gut in the spondyloarthropathies by performing ileocolonoscopies. In the first ileocolonoscopic studies of SpA patients, histological signs of gut inflammation were found in a relatively great number of patients, mostly without any clinical intestinal manifestations. These lesions were not seen in other inflammatory joint diseases. Further ileocolonoscopic studies confirmed the strong relationship between gut and joint inflammation. In patients in whom a second ileocolonoscopy was performed, remission of the joint inflammation was always connected with a disappearance of the gut inflammation, whereas persistence of locomotor inflammation was mostly associated to the persistence of gut inflammation. The hypothesis was proposed that some patients with a spondyloarthropathy had a form of subclinical Crohn's disease in which the locomotor inflammation was the only clinical expression. This hypothesis was confirmed in prospective long-term studies in which the ileocolonoscoped patients were reviewed 2 to 9 years later: about 6% of SpA patients not presenting any sign of Crohn's disease at first investigation but demonstrating gut inflammation on biopsy, developed full-blown Crohn's disease. The discovery of subclinical gut inflammation in the SpA had therapeutic consequences. Sulphasalazine (SASP) has been proven to be an active drug in the treatment of IBD. Since the gut could play a crucial role in SpA, it was logic to use this drug in the treatment of this disease. Multiple open and double-blind studies have proven the effectiveness of this drug in SpA; recent studies concluded that the beneficial effect of the drug in this disease entity is more prominent on the peripheral arthritis than on the axial disease.
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PMID:The role of gut inflammation in the pathogenesis of spondyloarthropathies. 895 Aug 41

Tenidap is a new antirheumatic drug currently undergoing clinical evaluation. It inhibits production and activity of cytokines in vivo and causes significant reductions in plasma markers of disease activity in rheumatoid arthritis. After the oral administration of C-14 labeled tenidap, bile, urine and plasma were examined by HPLC and atmospheric pressure tandem mass spectrometry. Label is excreted primarily in bile/feces and the remainder in urine, with good recoveries. Numerous metabolites were identified and the structures of most were confirmed by comparison with authentic synthetic samples. Hydroxylation in several positions on both the oxindole and thienyl rings of tenidap represents the major routes of metabolism; most of these metabolites are subsequently conjugated. The glucuronide of 5'-hydroxytenidap, excreted primarily in bile, is the major metabolite, constituting about one third of the oral dose recovered. Other pathways include dihydroxylation and methoxylation on the thienyl ring. An unusual reduction of hydroxytenidap took place, resulting in the formation of a novel thiolactone analog. Anaerobic incubation with rat cecal contents generated the thiolactone metabolite, suggesting the involvement of gut microflora.
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PMID:Disposition and metabolism of tenidap in the rat. 902 43

We carried out this study to determine if our patient population with rheumatoid arthritis (RA) has elevated levels of antibodies to gut bacteria. Seventy patients with RA were categorised as being either active or inactive on clinical grounds. Antibodies to the H and O antigens of Proteus mirabilis and Salmonella typhi were determined by tube agglutination method in these patients, 18 patients with osteoarthritis and 82 healthy controls. There was no significant difference in the anti-proteus antibody titres between both the control groups and patients with inactive disease. However, antibody levels among patients with active disease were significantly higher than controls (P < 0.001). There was no significant difference in anti-salmonella antibody titres among the various disease and control groups. Elevated antibody levels could suggest a role for Proteus as an etiological agent in RA.
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PMID:Elevated levels of anti-proteus antibodies in patients with active rheumatoid arthritis. 902 34

Orally administered autoantigens suppress autoimmunity in animal models, including experimental allergic encephalomyelitis, collagen and adjuvant-induced arthritis, uveitis, and diabetes in the non-obese diabetic mouse. Low doses of oral antigen induce antigen-specific regulatory T-cells in the gut, which act by releasing inhibitory cytokines such as transforming growth factor-beta, interleukin-4, and interleukin-10 at the target organ. Thus, one can suppress inflammation at a target organ by orally administering an antigen derived from the site of inflammation, even if it is not the target of the autoimmune response. Initial human trials of orally administered antigen have shown positive findings in patients with multiple sclerosis and rheumatoid arthritis. A double-blind, placebo-controlled, phase III multi-center trial of oral myelin in 515 relapsing-remitting multiple sclerosis patients is in progress, as are phase II clinical trials investigating the oral administration of type II collagen in rheumatoid arthritis, S-antigen in uveitis, and insulin in type I diabetes.
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PMID:Oral tolerance for the treatment of autoimmune diseases. 904 67

Mounting evidence suggests that there are a number of important, but poorly understand, interactions between dietary proteins and the human immune system. The usual response of the human immune system to dietary proteins seems to be that of oral tolerance, a phenomenon involving up-regulation of protective gut localized immune mechanisms and down-regulation of potentially harmful systemic immunity to the protein in question. Abrogation of oral tolerance may play an important role in the development of food allergies and food enteropathies. Immune mechanisms underlying oral tolerance are therefore discussed in light of current understanding of such food-related diseases as IgE mediated food allergies and gluten sensitive enteropathy. Possible development of oral vaccines to immune-related diseases like multiple sclerosis and rheumatoid arthritis is also discussed.
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PMID:Interactions between dietary proteins and the human system: implications for oral tolerance and food-related diseases. 913 Nov 92

To determine the prevalence of morphologic bowel lesions in patients with inflammatory rheumatic diseases and to better define the interactions between intestinal and articular pathology, 177 patients [39 with reactive arthritis (ReA), 40 with psoriatic arthritis (PsA), 23 with ankylosing spondylitis (AS), 21 with undifferentiated spondyloarthropathy (USpA) and 54 with rheumatoid arthritis (RA)] underwent ileocolonoscopy followed by multiple biopsies of the large bowel and the ileum and ileocecal valve. Biopsies were then examined with light and electron microscopy. During the endoscopic examination various degrees of gut inflammation were observed in 13% of ReA, 5% of PsA, 26% of AS, 14% of USpA and 11% of RA patients. At the histological examination those percentages were respectively 51%, 45%, 48%, 38%, and 15%, and at the electron microscopic examination 76%, 53%, 90%, 60%, and 50%. Our results show that an involvement of the gut is a factor in a large percentage of patients with spondyloarthropathy and, to a lesser extent, with RA. The involvement of the intestine in RA manifests itself mainly in ultrastructural lesions, thus this involvement is not so obvious as in the spondyloarthropathies; however, it could nonetheless play an important role in the etiopathogenesis of this disease.
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PMID:Intestinal histological and ultrastructural inflammatory changes in spondyloarthropathy and rheumatoid arthritis. 913 22

We report two cases of rheumatoid arthritis (RA) associated with Crohn's disease (CD). The first case was a 60-year-old man with longstanding CD who next developed a seropositive, nodular RA. This patient also had bilateral sacroiliitis, but without positive HLA B27. The second was a 65-year-old female with a 15-year history of seropositive RA who presented secondarily a CD. No sacroiliitis or nodules were found in this patient. Both patients were DR1 (DRB1* 0101). Gold salts were only given in the second case and were stopped many years before the gastrointestinal symptoms. A similar case report has been previously described consisting in an ulcerative colitis complicating a seronegative HLA-B27 RA with sacroiliitis. The gastrointestinal involvement in RA may be broad and includes many causes: drug-induced colitis (including gold enterocolitis) vasculitis and amyloidosis located in the gut, associated bowel disease such as collagenous colitis, and also infectious agents. In addition, erosive polyarthritis associated with gastrointestinal manifestations can present a problem in the differential diagnosis between RA and an enteropathic arthritis. Finally, the coexistence by chance of inflammatory bowel disease and RA is suggested by the low occurrence of these two conditions in the same patient.
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PMID:Crohn's disease associated with seropositive rheumatoid arthritis. 917 28

Eighteen patients with clinically active rheumatoid arthritis, satisfying the ARA criteria, were admitted to hospital for i.v. methylprednisolone pulse therapy. Studies of circulating lymphocyte subsets 1 h before and 24 h after pulsing were carried out together with studies on their adhesion to endothelium-containing lamina propria of porcine gut at various time points. Additionally, circulating VCAM-1 was estimated pre- and post-pulse by ELISA. We observed a marked fall (59%) in mononuclear cell adhesion 24 h post-pulse therapy (P < 0.001). Accompanying this was a significant, though slight, fall in circulating mononuclear cells (P < 0.01), mainly involving T cells. However, the degree of reduction in cell adhesion did not appear to reflect change in any particular circulating subset, but was more likely due to changes in adhesion molecule expression of several subsets. No significant change in circulating VCAM-1 was observed. It would appear, therefore, that the early beneficial effect of steroid pulsing in rheumatoid arthritis coincides with a demonstrable reduction in cell adhesion to gut. This may have implications for the pathogenesis of this disease.
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PMID:Steroid pulse therapy for rheumatoid arthritis: effect on lymphocyte subsets and mononuclear cell adhesion. 956 68


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