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)

Intra-articular injection of highly purified or recombinant interleukin 1 (IL-1) into the rabbit knee induces a transient synovitis with leucocytic infiltration into the synovial lining and joint cavity and loss of proteoglycan from articular cartilage. Tumour necrosis factor alpha (TNF-alpha), which has many of the actions of IL-1, in the dose range 50-5,000 ng induced infiltration of leucocytes into the joint but failed to cause significant proteoglycan loss from cartilage. The nature of the leucocytic infiltrate induced by intra-articular TNF-alpha was predominantly monocytic compared with the mixed polymorphonuclear (PMN)/monocytic infiltrate induced by IL-1. Neither cytokine induced the accumulation of significant numbers of lymphocytes. In addition, on a molar basis, TNF-alpha was significantly less active than IL-1 in causing cell accumulation in the joint. Injection of submaximal doses of IL-1 and TNF into the rabbit resulted in a marked synergy with respect to the accumulation of PMN. The conclusion from these studies is that TNF-alpha could contribute to the PMN accumulation in the human joint in rheumatoid arthritis but is unlikely to be important in the destruction of articular cartilage.
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PMID:Arthritogenic actions of recombinant IL-1 and tumour necrosis factor alpha in the rabbit: evidence for synergistic interactions between cytokines in vivo. 278 40

Limiting dilution analysis was performed in the presence of interleukin 2 (IL-2) on lymphocytes isolated from the synovial fluid (SF) and peripheral blood (PB) of patients with rheumatoid arthritis (RA) and PB of normal donors. Clones of these 'spontaneously' IL-2-responsive cells from PB and SF were compared for their reactivity with components of the extracellular matrix (i.e. native or denatured type I or type II collagen and proteoglycan). It was determined that all clones from both PB and SF were activated to produce interferon (IFN) in the presence of any of the connective tissue components (CTC). Clones derived from normal PB behaved in a similar fashion but produced lower IFN-gamma levels. There was a synergy between the CTC and serum or plasma fibronectin, which was more apparent when soluble CTC were used as the stimuli rather than immobilized CTC. The fibronectin alone was unable to induce IFN-gamma production under any of the conditions tested (i.e. soluble or immobilized). These results demonstrate that clones of IL-2-responsive T cells can be activated by interactions with connective tissue components to produce IFN-gamma.
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PMID:Lymphocyte extracellular matrix interactions. Induction of interferon by connective tissue components. 278 43

We show that purified human transforming growth factor-beta (1-10ng/ml) inhibits interleukin 1-stimulated loss of proteoglycan from cartilage in vitro. Inhibition is incomplete, as interleukin 1 retains the ability to cause a dose dependent stimulation of proteoglycan release in the presence of high levels of transforming growth factor-beta (100ng/ml) although both basal and interleukin 1-stimulated levels can be reduced by up to 50 per cent. This observation, together with its ability to stimulate proteoglycan synthesis and to stimulate proteinase inhibitor production, suggests a possible role for transforming growth factor-beta in limiting cartilage proteoglycan loss in inflammatory conditions such as rheumatoid arthritis.
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PMID:Transforming growth factor-beta causes partial inhibition of interleukin 1-stimulated cartilage degradation in vitro. 278 34

Cartilage proteoglycans were measured, by the use of an enzyme-linked immunosorbent assay, in synovial fluids obtained from 109 unselected patients attending an outpatient rheumatology clinic because of inflammation of the knee. The content of proteoglycans in synovial fluid was inversely related to the degree of joint destruction shown on X-ray. The proteoglycan concentrations in knee-joint exudates were higher in patients with reactive arthritis than in patients with rheumatoid arthritis having synovitis of corresponding duration and lacking radiological evidence of cartilage destruction. The measurement of proteoglycan levels may therefore be useful in differentiating between the two conditions.
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PMID:Difference in cartilage proteoglycan level in synovial fluid in early rheumatoid arthritis and reactive arthritis. 286 21

We investigated the role of insulin-like growth factors (IGFs) as regulating factors of cartilage metabolism in human synovial fluid (SF), using a bovine explant culture system that was shown to respond to recombinant IGF-1 in vitro. SF from rheumatoid arthritis (RA) patients and from control patients was found to stimulate chondrocyte proteoglycan synthesis in bovine articular cartilage. A monoclonal antibody directed primarily against IGF-1 (and to some extent, IGF-2) partially blocked the stimulatory action of serum and totally blocked the stimulation by SF. These findings indicate that IGFs are major regulating factors of cartilage proteoglycan synthesis in human SF. In addition, we measured serum and SF levels of IGF-1 in RA patients and control patients, using a radioimmunoassay. No difference in immunoreactive serum IGF-1 was detected between patients and controls. The IGF-1 levels in SF were consistently lower than in serum, for both patient groups. No differences in IGF-1 concentration were found between RA and non-RA SF. The relevance of these data with respect to joint inflammation is discussed.
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PMID:Insulin-like growth factor stimulation of chondrocyte proteoglycan synthesis by human synovial fluid. 291 64

The in-vitro viscoelastic mechanical response of normal rabbit articular cartilage is strongly dependent on the quantity and integrity of the proteoglycan fraction of the tissue matrix. Experimental results demonstrate that specific functional relationships exist between shear moduli, retardation time spectra, and proteoglycan content. Quantitative enzymolysis of the proteoglycan fraction of the tissue alters the form of these relationships in a fashion consistent with the altered physiochemical make-up of the tissue. The observed changes in mechanical behavior with controlled enzymolysis are similar to those associated with the early stages of osteoarthritis, rheumatoid arthritis, joint sepsis, and synovitis in animal models.
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PMID:Mechanical behavior of articular cartilage quantitative changes with enzymatic alteration of the proteoglycan fraction. 303 23

Antigen-induced arthritis in the rabbit (AIAR) provides the closest experimental equivalent to human rheumatoid arthritis in terms of infiltration of synovial tissue by lymphoid cells. A method is described for quantitative histological analysis of AIAR. Measurements of total cell numbers, lymphocyte and polymorphonuclear leucocyte infiltration, and thickness of infiltrated synovium were obtained for ranges of antigen dosage and duration of arthritis. The method has been devised as part of a system for the analysis of joint swelling, synovial fluid biochemistry and cytology, cartilage proteoglycan chemistry and synovial histology on the same specimen.
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PMID:Quantitative histological analysis of antigen-induced arthritis in the rabbit. 319 59

The concentrations of aminoterminal-type-III procollagen (procollagen N-) peptide, and of proteoglycans were measured in knee-joint synovial fluid and serum from patients with rheumatoid arthritis or reactive arthritis. All synovial fluids contained large amounts of intact propeptide. The synovial fluid: serum propeptide ratios were high, suggesting local propeptide liberation. A correlation was demonstrated between the propeptide concentration in synovial fluid and in serum. In rheumatoid arthritis, the propeptide concentration in synovial fluid was related to local inflammatory activity, and the serum concentration was correlated with the presence of nonspecific markers of inflammation. The presence of smaller propeptide fragments in synovial fluid indicated that some degradation occurred locally. The local metabolic changes were most prominent in patients with joint erosions. Patients with nonerosive rheumatoid arthritis and reactive arthritis had similar synovial fluid propeptide concentrations. The proteoglycan content of synovial fluid was inversely related to the degree of joint destruction, and was highest in patients with reactive arthritis. No correlation was observed between the concentrations of propeptide and proteoglycan in synovial fluid. Intraarticular glucocorticoid injection reduced the levels of propeptide and proteoglycan in synovial fluid.
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PMID:The aminoterminal-type-III procollagen peptide and proteoglycans in serum and synovial fluid of patients with rheumatoid arthritis or reactive arthritis. 325 5

Interleukin-1 beta (IL-1 beta) and proteoglycans have been quantified by radioimmunoassay (IL-1 beta) and enzyme linked immunosorbent assay (proteoglycans) in synovial fluids and sera from patients with rheumatoid arthritis (RA) and reactive arthritis. All fluids were also tested for their ability to influence proteoglycan metabolism in a cartilage explant culture system. Synovial fluid IL-1 beta concentrations were inversely related to proteoglycan concentrations in samples from both RA and reactive arthritis patients (P less than 0.002 for all patients). There was no statistically significant relation between immunoreactive IL-1 beta concentration and proteoglycan synthesis or degradation in explants cultured in synovial fluid containing medium. Synovial fluid IL-1 beta concentrations were not related to erythrocyte sedimentation rate or joint total leukocyte count. IL-1 beta was not detectable (limit 250 pg/ml) in any unextracted sera. Although it appears likely that IL-1 beta is involved in the inflammatory and degenerative processes in joint disease, our findings indicate that there is no simple positive relationship between immunoreactive levels of this cytokine in synovial fluid and liberation of proteoglycans from articular cartilage as reflected in synovial fluid proteoglycan concentration.
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PMID:Synovial fluid concentrations of interleukin-1 beta and proteoglycans are inversely related. 326 94

Polymorphonuclear leukocytes contain proteases that are capable of degrading articular cartilage matrix in disease states such as rheumatoid arthritis and osteoarthritis. In this study, the HL-60 human promyelocytic leukemia cell line was examined for ability to degrade cartilage proteoglycans. The HL-60 cells contained proteoglycan-degrading enzymes, which may contribute to the joint inflammation sometimes seen in acute leukemia. However, the protease activity was much less than in mature neutrophils and was not enhanced by the induction of myeloid maturation with dimethyl sulfoxide or retinoic acid. The diminished enzyme activity of induced HL-60 cells compared to normal neutrophils is another functional deficiency of these cells.
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PMID:Degradation of cartilage proteoglycans by myeloid leukemia cells. 327 41


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