Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018099 (gout)
 5,192 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interleukin 6 (IL-6), a multifunctional cytokine particularly active in regulation of the acute phase response, governs the terminal maturation of B lymphocytes and participates in early activation of T cells. IL-6 levels of synovial fluids of 153 patients with different arthritides were measured by a simple sandwich enzyme immunoassay. Highest IL-6 concentrations were detected in patients with rheumatoid arthritis (RA), particularly in those characterized by very active general symptoms and severe joint pain. High IL-6 levels were detected in patients with juvenile RA with polyarticular onset of disease and in gout. Corresponding to the suggested in vivo relevance of IL-6, dose correlation of IL-6 levels with the synovial IgM rheumatoid factor accumulation was demonstrated. The rate of the correlation between synovial IL-6 level and concentration of serum C-reactive protein in RA was inversely proportional to the dose of steroid treatment in patients with RA.
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PMID:Interleukin 6 levels in synovial fluids of patients with different arthritides: correlation with local IgM rheumatoid factor and systemic acute phase protein production. 837 Dec 34

Crystals of monosodium urate (MSU) provide a dose-dependent stimulus for the production by human blood monocytes of tumor necrosis factor (TNF), a cytokine with proinflammatory properties; TNF activity was inhibited selectively by monoclonal antibody to TNF alpha. Biologically active cell-associated TNF activity peaked at 3 h and was exceeded at 6 h by extracellular activity, which peaked at 12-18 h. Comparable kinetics were observed with immunoreactive TNF alpha. TNF alpha mRNA accumulation in monocytes stimulated with MSU crystals appeared as a single peak at 2-4 h, kinetics compatible with rapid production of a short half-life transcript. In contrast, crystals of calcium pyrophosphate or of hydroxyapatite did not stimulate significant production of TNF or of message. Fresh tophaceous material from a patient with gout contained significant levels of TNF alpha and cells cultured from the tophus produced TNF alpha in vitro. In rheumatoid synovial cells, spontaneous release of TNF alpha was increased by in vitro exposure to MSU crystals. Taken together with earlier work, these results support an expanded view of gouty inflammation in which the crystal-stimulated production of cytokines provides a crucial link between crystal deposition and many of the clinical and pathological facts of both acute and chronic gouty arthritis.
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PMID:Urate crystals stimulate production of tumor necrosis factor alpha from human blood monocytes and synovial cells. Cytokine mRNA and protein kinetics, and cellular distribution. 201 May 50

We reported before that monosodium urate (MSU) crystals were potent stimulators of endogenous pyrogen (EP) production from human and rabbit mononuclear phagocytes, and proposed that this property of MSU crystals may be important in the pathogenesis of gout. EP activity is now attributed to interleukin 1 (IL 1) peptides but IL 1 is not the only pyrogenic monocyte-derived cytokine, since both interferon-alpha (alpha-IFN) and tumor necrosis factor (TNF) are also pyrogenic in rabbits. Using a T cell comitogenic assay based on a murine helper T cell clone that does not respond to IFN or TNF, we now report the release of IL 1 activity from human blood monocytes and synovial fluid mononuclear cells (MNC), following stimulation with MSU crystals. MSU-induced supernatants with IL 1 activity were neutralized with rabbit antiserum to human IL 1 and also stimulated the growth ([3H]thymidine incorporation) of long-term fibroblast-like cell lines derived from human synovial rheumatoid exudate. Two other crystals associated with articular inflammation were tested: hydroxyapatite was a much less potent stimulus compared with MSU crystals, and calcium pyrophosphate dihydrate did not stimulate IL 1 release from human monocytes or synovial fluid MNC. As a model for the inflammatory consequences of acute and chronic overproduction of IL 1, gout is the only sterile inflammatory disease where the local and systemic pathology is compatible with such overproduction; raised IL 1 levels have been found at the site of inflammation, and a necessary etiologic agent, crystalline urate, has been shown unequivocally to be a direct activator of mononuclear IL 1 release.
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PMID:Interleukin 1 (IL 1) as a mediator of crystal arthritis. Stimulation of T cell and synovial fibroblast mitogenesis by urate crystal-induced IL 1. 303 70

Macrophages infiltrated into synovium play an important role in joint destruction in inflammatory joint diseases. In this study we focused on the production of monocyte chemoattractant protein-1 (MCP-1), a recently identified monocyte chemotactic protein, by inflammatory synovium. Synovial fluid (SF) from rheumatoid arthritis (RA), osteoarthritis, gout, and traumatic arthritis contained MCP-1. MCP-1 was produced in the synovium of patients with RA and other inflammatory joint disease in in vitro culture systems; differences in the amounts produced were not significant. Synovial MCP-1 production in RA was further investigated. Levels of MCP-1 were significantly correlated with levels of IL-1 beta, IL-6, and IL-8 in the culture supernatants of synovia from RA. Using immunohistochemical techniques, MCP-1 was detected in the lining and sublining cells and in the vascular endothelial cells of rheumatoid synovia. Rheumatoid synovia with active inflammation were stained more intensely by anti-MCP-1 antibody than were those with weak or inactive inflammation. IL-1 beta and TNF-alpha stimulated the expression of MCP-1 mRNA and de novo MCP-1 synthesis by cultured synovial cells. These results suggest the production of MCP-1 by synovium of various inflammatory joint diseases. In rheumatoid synovium, a cytokine network involving MCP-1 and other proinflammatory cytokines (IL-1 beta, IL-6, IL-8, and TNF-alpha) contributes to the immunopathogenesis of RA.
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PMID:Monocyte chemoattractant protein-1 (MCP-1) in inflammatory joint diseases and its involvement in the cytokine network of rheumatoid synovium. 840 45

Activin A is a cytokine whose multiple functions have yet to be fully determined. In this study, the role of proinflammatory cytokines in regulatory control of activin A production was shown in synoviocytes and chondrocytes. Additional facets of functional inflammation-related activities of activin A were also determined. Results showed that activin A concentrations in the synovial fluid of patients with rheumatoid arthritis and gout were elevated relative to those in patients with osteoarthritis. Further studies showed that production of activin A by synoviocytes and chondrocytes in culture was stimulated by cytokines such as IL-1, transforming growth factor-beta (TGF-beta), interferon-gamma (IFN-gamma), and IL-8, consistent with previous studies in regard to the control of activin A production in marrow stromal cells and monocytes by cytokines, glucocorticoids and retinoic acid. In addition, the relationship of activin A to IL-6-induced biological activities was investigated. Three major IL-6 activities involved in inflammatory responses were found to be suppressed by activin A. In a dose-dependent manner, activin A efficiently suppressed IL-6-induced proliferation of 7TD1 B lymphoid cells, phagocytic activity of monocytic M1 cells, and fibrinogen production in HepG2. Therefore, it is likely that activin A serves as a suppressor for IL-6, dampening inflammatory responses, and has the potential to perform some previously unrecognized roles in inflammation.
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PMID:Suppression of IL-6 biological activities by activin A and implications for inflammatory arthropathies. 956

In the present study, we analyzed the cytokine network among TNFalpha, IL-1beta, IL-8, and IL-1 receptor antagonist (IL-1Ra) in a rabbit experimental model of acute gout. The production of TNFalpha in synovial fluids reached the peak at 2 hours after the intra-articular injection of monosodium urate (MSU) crystals. The production of IL-1beta and IL-8 reached the first peak at 2 hours and the second peak at 9 and 12 hours, respectively. The production of endogenous IL-1Ra reached the peak at 9 hours. The source of TNFalpha and the first phase of IL-8 was synovial cells, whereas infiltrating leukocytes were the source of the second phase of IL-8 and also of IL-1beta and IL-1Ra. The production of TNFalpha was not altered by either anti-lL-8 IgG or IL-1Ra. The first IL-1beta peak was reduced only with a combination of anti-TNFalpha mAb and anti-lL-8 IgG, whereas the second peak was significantly reduced by either inhibitor. The first IL-8 peak was not altered with anti-TNFalpha mAb or IL-1 Ra, whereas the second IL-8 peak was reduced with IL-1Ra. Anti-TNFalpha mAb or anti-lL-8 IgG significantly reduced the peak level of endogenous IL-1Ra. These cytokine inhibitors also attenuated the maximal leukocyte accumulation at 9 hours, but not the initial phase, which occurred within 2 hours. These results provide evidence that IL-8 and TNFalpha were responsible for the production of IL-1beta and IL-1Ra, and that IL-1beta was responsible for the second phase of IL-1beta and IL-8 production. Our data also suggest that the initial and the maximal phases of leukocyte influx are differently regulated. Finally, the intravenous injection of colchicine inhibited neutrophil infiltration without affecting the production of TNFalpha or the first peak of IL-8, suggesting that colchicine inhibits MSU crystal-induced arthritis by directly inhibiting the migration of neutrophils.
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PMID:Analysis of the cytokine network among tumor necrosis factor alpha, interleukin-1beta, interleukin-8, and interleukin-1 receptor antagonist in monosodium urate crystal-induced rabbit arthritis. 960 81

Our objective was to investigate the clinical significance of Th1 and Th2-type cytokines, such as interferon-gamma (IFNgamma) interleukin (IL)-12, IL-4 and IL-10, in the mononuclear cells (MNC) of the synovial fluid (SF) in patients with rheumatoid arthritis (RA). The cytokine production in the MNC obtained from the SF (SF-MNC) in 30 patients with RA and 10 with gout was examined by measuring the mRNA levels of IFNgamma, IL-12, IL-4 and IL-10 by semiquantitative RT-PCR. The mRNA levels of IFNgamma, IL-4 and IL-10 were significantly higher in the SF-MNC of RA patients than in those of gout patients (p<0.001, p<0.01 and p<0.001, respectively). Correlations between mRNA levels were significant for IL-12 and IL-4, IL-12 and IL-10, and IL-4 and IL-10 (p<0.05). The mRNA levels of IL-4 and IL-10 were very low compared to those of IL-12 in seven of the 30 patients with RA; all of these patients were in stage 4, and serum levels of CRP, ESR and blood platelet count which are considered as indices of the severity of inflammation, were significantly elevated in these seven patients compared to the other 23 RA patients. The markedly reduced synthesis of both IL-4 and IL-10 mRNA could be considered to be related to the progression and/or activity of RA. The results of this study therefore indicate an imbalance in the levels of Th1 and Th2 cytokines at the site of inflammation in RA, and draw attention to the possibility of treatment of progressive or intractable RA with IL-4 and/or IL-10.
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PMID:Significance of low mRNA levels of interleukin-4 and -10 in mononuclear cells of the synovial fluid of patients with rheumatoid arthritis. 1105 25

Gout tophi are characterised by foreign body granulomas consisting of mono- and multinucleated macrophages surrounding deposits of monosodium urate microcrystals. After primary formation, granulomas grow associated with degradation of the extracellular matrix. Based on this background, we have sought (1) to investigate whether during granuloma's growth new macrophages are recruited into the tophi, (2) to find in situ evidence for macrophages' active role in matrix degradation and (3) to examine whether shrunk cells seen within gout tophi are apoptotic. Immunohistochemistry showed that perivascular localised mononuclear cells are CD68+, S100A8+, S100A9+, 25F9-, representing freshly migrated monocytes/macrophages. In contrast, almost all CD68+ mono- and multinucleated cells arranged within granulomas were S100A8-, S100A9-, 25F9+, representing mature (non-migrating) macrophages. Serial sections revealed that macrophages co-express tumour necrosis factor (TNF)-alpha and matrix metalloproteinases (MMPs) 2 and 9. In situ end-labelling of fragmented DNA demonstrated that CD68+ macrophages undergo apoptosis within gout tophi. Our data show that macrophages are continuously recruited into the gout tophi. These macrophages co-produce the proinflammatory cytokine TNF-alpha and two TNF-alpha inducible lytic enzymes, MMP-2 and MMP-9, suggesting that TNF-alpha may induce MMP production followed by matrix degradation within foreign body granulomas. In parallel, macrophages undergo apoptosis, a phenomenon that may restrict the destructive potential of inflammatory macrophages.
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PMID:Continuous recruitment, co-expression of tumour necrosis factor-alpha and matrix metalloproteinases, and apoptosis of macrophages in gout tophi. 1114 75

Blood uric acid levels and purine metabolism are affected in many ways after bone marrow transplantation (BMT). Although BMT is usually performed when patients have a low residual disease burden, a proportion of them are still at risk of tumor lysis syndrome, even with limited disease or after nonmyeloablative conditioning regimens; moreover, an alteration in uric acid turnover can also be observed in patients with persistently normal uric acid blood levels. Apart from this obvious complication, multiple physiopathological events occurring after transplantation may derange uric acid homeostasis. Although there is only indirect evidence (derived from obstetric eclampsia and experimental gout arthritis), a transplant-related increase in cytokine production (particularly TNF, IL-1 and IL-6) may activate xanthine oxidase which, in turn, may be responsible for a further cytokine bout: deranged cytokine homeostasis is involved in the pathogenesis of some of the main acute post-BMT complications, such as hepatic veno-occlusive disease (VOD) and acute graft-versus-host disease (aGVHD). Hyperuricemia is also a well-known side effect of cyclosporine A, the reference drug for the prevention of post-BMT GVHD, which may affect uric acid turnover by reducing glomerular filtration and/or affecting tubular handling; the available evidence favors the former explanation. Hyperuricemia is found in long-term transplanted patients as part of a metabolic pattern reminiscent of the so-called 'X' or 'metabolic'syndrome related to insulin resistance: there is still no precise interpretation of this post-transplant complication nor any definite data concerning its real incidence and outcome. Hyperuricemia is frequently regarded as a marginal finding in the context of X syndrome, but it is pathogenetically linked to the other component of the syndrome and has proved to be autonomously responsible for tissue and vessel damage. Finally, BMT is a possible therapeutic strategy for some inherited forms of hyperuricemia, particularly Lesch- Nyhan disease, although there is still some perplexity concerning the possibility of preventing the development of neurological impairment.
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PMID:Hyperuricemia and bone marrow transplantation. 1560 10

Pathogenesis of gout inflammation remains unknown, but recent advances have been made with respect to initiation, amplification, and self-limitation. Direct crystal-cell membrane contact leads to cell activation, involving membrane-associated molecules. Resolution of acute gout inflammation is a mechanism that is controlled by monocyte-macrophage switch, which results in the loss of cytokine production capability and, conversely, the ability to produce anti-inflammatory molecules. MRI and ultrasound findings provide preliminary data that are not yet used in clinical trials. Diagnosis and management recommendations are missing, but this gap will be filled soon with the upcoming European League Against Rheumatism Task Force's recommendations on gout.
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PMID:Gout: update on some pathogenic and clinical aspects. 1671 81


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