Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003864 (arthritis)
 69,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The matrix metalloproteinases (MMPs) constitute a family of multidomain zinc endopeptidases which contain a catalytic domain with a common metzincin-like topology. The MMPs are involved not only in extracellular matrix degradation, but also in a number of other biological processes. Normally, their proteolytic activity is regulated precisely by their main endogenous protein inhibitors, in particular the tissue inhibitors of metalloproteinases (TIMPs). Disruption of this balance results in serious diseases, such as arthritis, tumour growth and metastasis, rendering the MMPs attractive targets for inhibition therapy. Knowledge of their tertiary structures is crucial for a full understanding of their functional properties. Since the first publication of atomic MMP structures in 1994, much more structural information has become available on details of the catalytic domain, on its interaction with synthetic and protein inhibitors, on domain organization and on the formation of complexes with other proteins. This review will outline our current knowledge of MMP structure.
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PMID:Structural basis of matrix metalloproteinase function. 1458 78

Integrity of cartilage fails in joint disease. The current work aimed to identify candidate active proteinases in joint diseases using an in vitro model for cartilage degradation induced by interleukin-1. A critical event in the process of cartilage destruction in joint disease is the failure of the collagen fiber network to maintain integrity. Proteins binding to the surface of the fibers are likely early points of failure. Fibromodulin, a member of the leucine-rich repeat protein family, is one predominant protein in cartilage and is known for its roles in the formation of collagen fibrils and sustained interaction with these formed fibers. Cleavage removes the tyrosine sulfate-rich region in the N terminus of fibromodulin. Whereas fibromodulin bound to collagen in tissue was digested, purified fibromodulin was not cleaved. In contrast an N-terminal 10-kDa fragment, Gln19-Lys98, of the protein generated by Lys-C digestion contains the cleavage site and was a substrate cleaved by the enzyme in medium from stimulated cultures. In solution, digestion of this substrate with matrix metalloproteinase (MMP)-2, -9, -8, and -13 demonstrated that only MMP-13 was capable to efficiently cleave it. The cleavage product obtained after MMP-13 digestion was identical to that observed in cleaved fibromodulin from cartilage explant cultures stimulated with interleukin-1. MMP-13 treatment of fresh articular cartilage also produced the fragment under study. The elucidation of the enzyme responsible for such cleavage may lead to treatment modalities involving its selective inhibition for patients suffering from arthritis. The known structure of the fragments permits the generation of neo-epitope antibodies to the cleavage site, which can be used to detect ongoing cartilage degradation in patients with arthritic disease, an important adjunct in monitoring disease progression, active disease, and efficacy of treatment.
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PMID:Cleavage of fibromodulin in cartilage explants involves removal of the N-terminal tyrosine sulfate-rich region by proteolysis at a site that is sensitive to matrix metalloproteinase-13. 1466 Jun 26

The matrix metalloproteinases (MMPs) constitute a family of secreted/cell-surface-anchored multidomain zinc endopeptidases, all of which exhibit a catalytic domain of a common metzincin-like topology, and which are involved in degradation of the extracellular matrix but also in a number of other biologic processes. Normally, the proteolytic activity of the MMPs is precisely regulated by their main endogenous protein inhibitors, in particular the tissue inhibitors of metalloproteinases (TIMPs). Disruption of this balance results in serious diseases such as arthritis, tumor growth, and tumor metastasis, rendering the MMPs attractive targets for inhibition therapy. Knowledge of their tertiary structures is crucial for a full understanding of their functional properties and their associations with dysfunctions. Since the reports of the first atomic structures of MMPs and TIMPs in 1994, considerable structural information has become available about both of these families of substances. Many of the MMP structures have been determined as complexes with synthetic inhibitors, facilitating knowledge-based drug design. This review focuses on the currently available 3D structural information about MMPs and TIMPs.
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PMID:Structural basis of matrix metalloproteinases and tissue inhibitors of metalloproteinases. 1466 38

Articular cartilage is a complex tissue maintained by chondrocytes, which undergo metabolic changes as a result of aging, disease, and injury. These changes may hinder tissue maintenance and repair, resulting in accelerated loss of articular surface and leading to end-stage arthritis. Researchers are investigating both normal and pathologic cellular and molecular processes as well as the development of chondroprotective agents to improve the metabolic function of articular cartilage. Current research is helping to clarify the mechanisms by which a variety of agents, such as glucosamine, chondroitin sulfate, hyaluronic acid, green tea, glucocorticoids, and nonsteroidal anti-inflammatory drugs, can modify the symptoms and course of osteoarthritis. Also under investigation are methods of stimulating repair or replacing damaged cartilage, such as matrix metalloproteinase inhibitors, gene therapy, growth factors, cytokine inhibitors, and artificial cartilage substitutes. Tissue engineering, the combining of artificial matrices with cells and growth factors or genes, offers great potential for improving patient care.
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PMID:Articular cartilage biology. 1468 27

Tissue factor (TF), a transmembrane receptor for plasma factor VII(a), is the main initiator of the coagulation cascade. It has also been implicated in noncoagulant processes, including inflammation. The function of the TF cytoplasmic domain was studied in mice in which 18 of the 20 cytoplasmic amino acids were deleted. This mutation (TF(deltaCT/deltaCT)) is not associated with alterations in blood coagulation. Arthritis was induced by intra-articular injection of methylated bovine serum albumin (mBSA) in mice preimmunized with mBSA. Arthritis severity was significantly reduced in TF(deltaCT/deltaCT) mice compared to wild-type mice, including reductions in synovitis, synovial exudate, cartilage degradation, and bone damage. A marked reduction in synovial interleukin (IL)-1beta and IL-6 mRNA was also observed. Serum anti-mBSA IgG1, but not IgG2a, was increased in mutant mice. Cutaneous delayed-type hypersensitivity and antigen-induced T-cell proliferation were reduced in TF(deltaCT/deltaCT) compared to wild-type mice. A significant down-regulation of lipopolysaccharide-induced IL-1, tumor necrosis factor, IL-6, macrophage migration inhibitory factor, and matrix metalloproteinase-13 mRNA was observed in immunized, but not in naive TF(deltaCT/deltaCT) macrophages ex vivo. These data suggest a significant role for the cytoplasmic domain of TF in the regulation of the immunoinflammatory responses, a murine arthritis model, and macrophage function.
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PMID:Reduction in arthritis severity and modulation of immune function in tissue factor cytoplasmic domain mutant mice. 1469 25

Qing-Luo-Yin (QLY), a traditional Chinese herbal medicine for the treatment of rheumatoid arthritis, is a combination of the extracts of Sophora flavescens Ait., Phellodendron amurense Rupr., Sinomenium acutum Rehd. et Wils. and Dioscorea hypoglauca Palib. The suppressive effect of QLY on the development of angiogenesis was investigated in a rat model of collagen-induced arthritis (CIA). QLY (0.3 g/kg) was orally administered daily for 27 days. Neo-angiogenesis, pannus and cartilage damage, the expression of metalloproteinases (MMP)-3 messenger RNA (mRNA) and the level of the tissue inhibitor of matrix metalloproteinase (TIMP)-1 in the synovium were examined by histology, in situ hybridization and immunohistochemiscal assays, respectively. It was observed that the articular morphological alterations, the over-expression of MMP-3 mRNA and the reduced production of TIMP-1 in CIA rats were significantly ameliorated by QLY. QLY performed about as effectively as tripterygium glycosidorum tablets (0.1 g/kg) extracted from Tripterygium wilfordii Hook. f.. These results indicate that QLY exerts a suppressive effect on the angiogenesis of CIA rats, and suggest that the therapeutic effect of QLY could be due to restoring the balance of MMP-3 and TIMP-1 in rheumatoid synovium.
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PMID:Suppressive effects of a Chinese herbal medicine qing-luo-yin extract on the angiogenesis of collagen-induced arthritis in rats. 1469 74

In this study we quantified the levels of matrix metalloproteinase-2 and 9 (MMP-2 and 9) in effusions and serial synovial cultures of patients with arthritis of the knee in order to investigate the correlations between MMP and cell counts in effusions as well as the possible roles of the synovium. In 49 patients with arthritis of the knee (series I) we examined the cell counts and the amounts of MMP-2 and 9 in 51 effusions. In 20 knee samples of series I of patients who received arthroscopy (series II), we examined the amounts of MMP-2 and 9 in effusions and serial synovial organ cultures. We also compared the gene expressions of MMP-2 and 9 and MT1-MMP in serial synovial cultures using RT-PCR. In series I, significantly more proMMP-9 appeared in effusions from the inflammatory group than in the non-inflammatory and hemorrhagic group ( p <0.001). The levels of proMMP-9 correlated with the neutrophil counts in the effusions ( p <0.001). In series II synovial cultures, the activities of latent and activated forms of MMP-2 and 9 in lesional areas were all higher than that in paralesional ones ( p <0.05). In RT-PCR analysis, MMP-2, -9 and membrane type 1 MMP mRNA levels of lesional areas also showed increased expression. Our data suggest that the analysis of MMP-9 indicates the inflammatory condition of the joints and that additional synovectomy may be beneficial for patients with inflammatory synovitis, compared with non-inflammatory and hemorrhagic arthritis.
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PMID:The significance of altered gelatinase expression in the synovium of patient with arthritic effusions. 1474 77

Matrix metalloproteinases (MMPs), also called matrixins, are proteinases that participate in extracellular matrix remodelling and degradation. Under normal physiological conditions, the activities of MMPs are precisely regulated at the level of transcription, of activation of the pro-MMP precursor zymogens and of inhibition by endogenous inhibitors (tissue inhibitors of metalloproteinases; TIMPs). Alteration in the regulation of MMP activity is implicated in diseases such as cancer, fibrosis, arthritis and atherosclerosis. The pathological effects of MMPs and TIMPs in cardiovascular diseases involve vascular remodelling, atherosclerotic plaque instability and left ventricular remodelling after myocardial infarction. Since excessive tissue remodelling and increased matrix metalloproteinase activity have been demonstrated during atherosclerotic lesion progression (including plaque disruption), MMPs represent a potential target for therapeutic intervention aimed at modification of vascular pathology by restoring the physiological balance between MMPs and TIMPs. This review describes the members of the MMP and TIMP families and discusses the structure, function and regulation of MMP activity; finally, pharmacological approaches to MMP inhibition are highlighted.
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PMID:Matrix metalloproteinases, inflammation and atherosclerosis: therapeutic perspectives. 1506 49

The aim of this study was to investigate the relationship between the biochemical markers of arthritis and the radiographic grading of osteoarthritis (OA) in knees. Seventy-one women aged 49-85 years with knee OA were studied. Anterior-posterior knee radiographs and hand radiographs were taken in all patients. The radiographic grading of OA in the knee was performed by using the Kellgren-Lawrence criteria and the joint space width. The 71 patients with knee OA were divided into two groups: 37 patients exhibiting generalized osteoarthritis (GOA) and 34 non-GOA patients, according to the grading of their hand radiograph. C-reactive protein (CRP), urinary pyridinoline, YKL-40, plasma matrix metalloproteinase (MMP)-3, MMP-9 and tissue inhibitor of metalloproteinases (TIMP)-1 were measured as the biochemical markers of arthritis. The radiographic grading with the Kellgren-Lawrence scale revealed a significant relationship to the joint space width (P = 0.003): the joint space width decreased with increasing Kellgren-Lawrence grade. All biochemical markers had negative correlations with the joint space width, but only urinary pyridinoline had a significant correlation (P = 0.039). Pyridinoline (P = 0.034) and TIMP-1 (P = 0.017) also exhibited a significant relationship to the Kellgren-Lawrence grade. In GOA evaluations, the joint space width did not differ between GOA and non-GOA patients. CRP, pyridinoline, YKL-40 and MMP-3 levels were significantly greater in GOA patients than in non-GOA patients. CRP, pyridinoline, YKL-40, MMP-3 and TIMP-1 levels each related to at least one of the radiographic gradings. Furthermore, pyridinoline related to every type of radiographic grading examined in the present study.
Arthritis Res Ther 2004
PMID:Relationship between radiographic grading of osteoarthritis and the biochemical markers for arthritis in knee osteoarthritis. 1514 66

Inflammatory articular cartilage diseases such as arthritis and osteoarthritis are characterized by a loss of articular cartilage due to an imbalance between synthesis and degradation of the extracellular cartilage matrix. These diseases are accompanied by an increased induction of cytokines such as interleukin 1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha). The increased release of cytokines leads to an enhanced production of matrix-degrading enzymes e.g. the matrix metalloproteinases (MMPs). In this study the direct antirheumatic effects of an extract of the secondary root of the African devil's claw (Harpagophytum procumbens DC) on the production of MMPs in IL-1beta-stimulated human chondrocytes were examined. A detailed evaluation by immunomorphological methods and Western blot analysis showed that the extracts of Harpagophytum decreased significantly the production of MMPs (MMP-1, MMP-3, MMP-9) in chondrocytes. The IL-1beta-induced production of MMPs was also significantly reduced by both a JM-extract (Jucurba) containing 210 mg dry extract and JF-extract (Jucurba forte) containing 480 mg dry extract. After all it could be shown that the effect of JF-extract on the MMP-synthesis was more pronounced in untreated and cytokine-stimulated chondrocytes when compared with the effect of the JM-extract. The capability of the JM-extract to suppress the MMP-production via the inhibition of the synthesis of inflammatory cytokines could explain its therapeutic effect in arthritic inflammations. In these in vitro experiments the JF-extract showed a higher efficacy than the JM-extract.
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PMID:[Effect of a Harpagophytum procumbens DC extract on matrix metalloproteinases in human chondrocytes in vitro]. 1514 34


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