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)

Following a washout period of 7 days, twenty-one patients suffering from rheumatoid arthritis and 3 from osteo-arthritis, who all required articular puncture were given a non-steroidal anti-inflammatory drug pirazolac 450 mg b.d. for 7 days. After discontinuation of the treatment the subjects were divided into 4 groups each of 6 patients. The non protein bound fraction of pirazolac in synovial fluid (0.86%) was significantly higher than that in plasma (0.53%). The average pirazolac concentration in plasma within the dosing interval fluctuated between 30.9 micrograms/ml and 59 micrograms/ml, and in synovial fluid between 16.6 micrograms/ml and 29.9 micrograms/ml. The half-life of pirazolac calculated from the measured and interpolated data from all patients was 30.9 h in plasma and 66.2 h in synovial fluid. The absolute free concentrations in plasma and synovial fluid (approx. 250 ng/ml) were in the range of the IC50-values for inhibition of cyclooxygenase in mouse peritoneal macrophages.
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PMID:Transsynovial distribution and protein binding of pirazolac in patients with rheumatoid arthritis. 379 28

Ibuprofen has wide applications in the treatment of rheumatoid arthritis and osteoarthroses as an effective non-steroidal antiinflammatory drug. The drug is still being investigated regarding its possible ability to reduce myocardial infarct size. The more potent biphenyl propionic analogue, flurbiprofen, has recently been introduced. Both drugs are strong inhibitors of cyclooxygenase. The specific HPLC-method described requires plasma samples of 100 microliter which are deproteinized and simultaneously extracted with acetonitrile containing either of the drugs as internal standard. Aliquots of 25 microliter of this primary extract were directly injected on a mu Bondapack C18 column. For elution was used a mixture of 60% methanol and 40% 50 mM phosphate buffer adjusted to pH 4.6. The detection limit (at 214 nm) for both drugs corresponded to plasma concentrations of about 0.2 micrograms X ml-1. The applicability of the method was demonstrated in a pharmacokinetic ibuprofen experiment in an adult person.
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PMID:Rapid HPLC-determination of ibuprofen and flurbiprofen in plasma for therapeutic drug control and pharmacokinetic applications. 381 66

Aspirin and a large number of nonsteroidal anti-inflammatory drugs act primarily through the inhibition of prostaglandin synthesis by inhibiting the enzyme cyclooxygenase. Other groups of biologically active polyunsaturated fatty acid derivatives including the leukotrienes, are generally not inhibited by this class of drugs in the same concentration ranges. Inhibition of the vasodilator prostaglandins, prostaglandin E2 and prostacyclin, as well as the leukotrienes, may reduce their inflammatory effects in several disease states. In addition, prostaglandin synthesis is also inhibited by glucocorticoids even though their mode of action may involve other effects as well. Prostaglandin E2 stimulates the osteoclastic reabsorption of juxtaarticular bone; its inhibition by nonsteroidal anti-inflammatory agents may, therefore, retard the process of bone erosion in rheumatoid arthritis and in other inflammatory processes. Inhibition of prostaglandin synthesis by these drugs accounts for many of their major toxic effects, including gastritis, which is the most common side effect; precipitation or aggravation of renal failure; fluid retention; hyperkalemia; antiplatelet effects with hemorrhagic phenomena; and aggravation of asthma and rhinosinusitis. Inhibition of prostaglandin synthesis can, therefore, account for most of the therapeutic as well as toxic effects of the nonsteroidal anti-inflammatory agents. Inhibition of pathways of synthesis of other important mediators, such as leukotrienes, are currently under investigation and may provide another approach for the development of new therapeutic agents.
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PMID:Prostaglandins and the mechanism of action of anti-inflammatory drugs. 641 64

Recent data from several laboratories, which suggest that generally accepted concepts relating to the mechanism of action of nonsteroidal, anti-inflammatory drugs (NSAIDs) in rheumatoid arthritis may be incorrect, are reviewed. Over the past decade, most researchers have espoused the idea that NSAIDs act by inhibiting cyclooxygenase, thereby removing prostaglandins, which are thought to be responsible for pain and inflammation. Recent studies demonstrating that prostaglandins have important immunomodulating properties and that NSAIDs actually provide partial correction of several immunoregulatory dysfunctions in patients with rheumatoid arthritis are described. In addition, some NSAIDs inhibit migration along with other monocyte and polymorphonuclear leukocyte functions. Data suggest that these actions are not related to inhibition of cyclooxygenase.
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PMID:Mechanism of action of nonsteroidal anti-inflammatory agents. 643 8

The recent demonstration of cytolytic mediators within synovial CD4+ T-cells of patients with rheumatoid arthritis (RA) has suggested an additional role for these cells in the pathogenesis of the disease. In this study we have investigated the function and regulation of antigen-specific class II-restricted cytotoxic T-cells from the synovial fluid (SFMNC) and peripheral blood (PBMNC) of 20 seropositive RA patients, and correlated in vitro findings with clinical data. Regulatory factors including prostaglandin E2 (PGE2), interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) were measured in cell supernatants. A diversity in SFMNC antigen-specific cytotoxicity that correlated with therapy and PGE2 production was found, and shown to be mediated by synovial prostanoid (products of cyclooxygenase metabolism) inhibition of effector function. Our findings indicate that SFMNC cytotoxicity may be important in the pathogenesis and treatment of RA. Cyclooxygenase inhibition as the sole treatment early in RA may reduce the potentially beneficial inhibitory effect of synovial prostanoids on antigen-specific SFMNC cytotoxicity.
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PMID:Prostanoid modulation of synovial antigen-specific CD4+ T-cell cytotoxic function in rheumatoid arthritis. 753 39

Freund's adjuvant arthritis (FAA) in susceptible rats (male, Lewis strain) is a well-established experimental model of rheumatoid arthritis to evaluate inherent drug properties, i.e. anti-inflammatory and/or immunosuppressive/immunomodulatory properties which are only ascertained by combining multiple parameter analysis. We employed a synoptic multiparametric evaluation system for the multifaceted FAA, a so-called "spider scheme", to facilitate a more rapid and easier comparison of qualitative and quantitative drug properties by visual display than that achieved by mere tabulation of the data. The spider scheme comprised six well-established parameters to evaluate the FAA disease (primary and secondary hind paw swelling, arthritic index which included macroscopic alterations of non-injected paws, nose, ears and tail, body weight changes and relative organ weights of thymus and spleen). By calculation of an index as a percent change in comparison to control and untreated diseased animals, the degree of improvement or impairment of the FAA by a tested compound could easily be entered into the spider scheme. The FAA parameter spider scheme clearly differentiated the most beneficial immunomodulatory properties of cyclosporin A from those of the immunosuppressive agents dexamethasone and cyclophosphamide as well as from the mere anti-inflammatory cyclooxygenase inhibitors. Among this latter class of non-steroidal anti-inflammatory compounds, a similar profile was demonstrated for indometacin and diclofenac, as well as for tenidap, which is claimed to have cytokine-modulating properties, as reflected by the reduction of acute-phase proteins in patients with rheumatoid arthritis. Yet, in this FAA model, with tenidap, no additional qualitative drug properties could be discerned.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antirheumatic drug profiles evaluated in the adjuvant arthritis of rats by multiparameter analysis. 784 84

Tenidap is a novel antirheumatic drug which combines non-steroidal antiinflammatory drug-like cyclooxygenase inhibition with cytokine modulating qualities in rheumatoid arthritis. We show herein that tenidap (5-20 microM) inhibited protein kinase C-mediated signalling leading to release of arachidonate in mouse macrophages by interfering with the up-regulation of the 85 kDa arachidonate-mobilizing phospholipase A2, although it did not inhibit this enzyme directly. The Ca(2+)-mediated activation of arachidonate mobilization was inhibited only at higher concentrations (20-40 microM). Studies of protein phosphorylation indicated that tenidap in itself was capable of inducing the phosphorylation of several protein bands through interaction with intracellular protein kinases and/or phosphatases. Importantly, tenidap inhibited both arachidonate release and the increase in intracellular protein phosphorylation when the cells were stimulated with zymosan. We propose that the main inhibitory influence of tenidap on the macrophage signalling investigated here is exerted at some level between protein kinase C and the 85 kDa phospholipase A2 and quite possibly also at the receptor-linked activation of phospholipase C.
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PMID:Effects of tenidap on Ca(2+)- and protein kinase C-mediated protein phosphorylation, activation of the arachidonate-mobilizing phospholipase A2 and subsequent eicosanoid formation in macrophages. 794 11

High levels of immunoreactive cyclooxygenase (Cox; prostaglandin H synthase) are present in synovia from patients with rheumatoid arthritis (RA). We now show that the recently identified inducible isoform of Cox, Cox-2, is expressed in synovia from patients with RA. To further explore modulation of the Cox isoforms in RA synovial tissues, we examined the expression and modulation of Cox-1 and -2 in rheumatoid synovial explant cultures and cultured rheumatoid synovial fibroblast-like cells (synoviocytes). Immunoprecipitation of in vitro labeled proteins and Western blot analysis demonstrated the presence of both Cox-1 and -2 under basal conditions in freshly explanted rheumatoid synovial tissues. De novo synthesis of Cox-2 polypeptide was enhanced by IL-1 beta or PMA, and dramatically suppressed by dexamethasone (dex). Cox-1 expression, under the same conditions, showed only minor variation. Since mRNA for Cox-2 is highly unstable, we examined the regulation of Cox-2 transcripts in cultured rheumatoid synoviocytes. Under basal conditions both Cox-1 and -2 mRNAs were present at low levels, but Cox-2 mRNA was markedly increased by treatment with IL-1 beta or PMA. dex markedly suppressed the induction of Cox-2 mRNA. In sharp contrast, Cox-1 transcripts were not modulated by IL-1 beta or dex. These data suggest that modulation of Cox-2 expression by IL-1 beta and corticosteroids may be an important component of the inflammatory process in synovial tissues from patients with RA.
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PMID:Cyclooxygenase-1 and -2 expression in rheumatoid synovial tissues. Effects of interleukin-1 beta, phorbol ester, and corticosteroids. 813 48

Histamine and IL-1 have been implicated in the pathogenesis of chronic inflammatory diseases, such as pulmonary allergic reactions and rheumatoid arthritis. We therefore investigated whether histamine modulated the synthesis of IL-1 beta. Human PBMC were stimulated with IL-1 alpha (10 ng/ml) in the absence or presence of histamine (10(-9)-10(-4) M). Histamine alone did not induce protein synthesis or mRNA accumulation for IL-1 beta. IL-1 alpha-induced IL-1 beta synthesis was enhanced two to threefold by histamine concentrations from 10(-6)-10(-4) M. Cimetidine, an H2 receptor antagonist, reversed the histamine (10(-5) M)-mediated increase in IL-1 alpha-induced IL-1 beta synthesis. Diphenhydramine, an H1 receptor antagonist, had no effect. Indomethacin, a cyclooxygenase inhibitor, significantly reduced IL-1 alpha-induced IL-1 beta synthesis, but had no effect on the histamine-mediated increase in IL-1 alpha-induced IL-1 beta synthesis. Histamine (10(-5) M) enhanced and sustained IL-1 beta mRNA levels in IL-1 alpha-stimulated PBMC. However, histamine reduced IL-1 beta mRNA half-life (2.4 vs 1.2 h), suggesting that histamine enhances IL-1 alpha-induced IL-1 beta synthesis at the level of transcriptional activation. On the other hand, histamine (10(-5) M) did not affect IL-1 alpha-induced synthesis of IL-1 receptor antagonist. These results suggest that mast cells may sustain chronic inflammatory processes by upregulating self-induction of IL-1 through histamine release.
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PMID:Histamine enhances interleukin (IL)-1-induced IL-1 gene expression and protein synthesis via H2 receptors in peripheral blood mononuclear cells. Comparison with IL-1 receptor antagonist. 832 95

Conventional drug therapy in rheumatoid arthritis (RA) has failed to control the longterm morbidity and mortality associated with RA. Similarly, drug therapy for osteoarthritis (OA) can relieve symptoms, but it is not clear that it alters progression of disease. Three classes of drugs are widely used for treatment of RA: nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and the slow-acting agents. In most patients, pharmacologic therapy is initiated with NSAIDs. These drugs can relieve symptoms but do not alter the course of the disease. The gastrointestinal and other side effects attributed to these compounds are well known. Similarly, use of corticosteroids can provide rapid pain relief to patients with RA and, if used in low doses, pose limited risk of toxicity. Slow-acting agents, including gold, d-penicillamine, and methotrexate, appear to decrease radiographic progression and improve clinical and biochemical indicators of RA. Therefore, newer treatment philosophies encourage use of slow-acting agents earlier in the course of the disease in order to prevent or diminish bone and joint erosions and destruction and other manifestations of disease progression. Drugs under investigation for the treatment of arthritis appear to exhibit disease-modifying or immunomodulating properties. Tenidap is a novel agent that possesses a dual mechanism of action: cyclooxygenase inhibition and modulation of cytokine activity. In addition, several biologic agents, including antibodies to tumor necrosis factor-alpha (TNF-alpha) and to intercellular adhesion molecule-1, may prove useful. These immunotherapeutic strategies are based on knowledge of the role of cytokines in the inflammatory process in arthritis. Osteoarthritis may be managed using drug and nondrug modalities. Weight loss is especially important when OA is in the weight-bearing joints. Biopsies of synovium from patients with OA show evidence of inflammation, but whether this disease should be treated with analgesics alone or with anti-inflammatory drugs remains controversial. Other treatment modalities, including tissue transplants and cytokine-modulating drugs, are emerging for the potential therapy of OA. Surgery may also be appropriate if drug treatment fails to control symptoms.
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PMID:Management of osteoarthritis and rheumatoid arthritis: prospects and possibilities. 860 23


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