Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.17 (MMP-3)
 3,419 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of messenger RNA encoding neutral metalloproteinases and the tissue inhibitor of metalloproteinases (TIMP) in human arthritic synovium was evaluated in situ, using RNA probes. Interstitial collagenase and stromelysin were expressed by synovial lining cells in patients with active rheumatoid arthritis (RA). Proteinase messenger RNA was found both in cells expressing mononuclear phagocyte antigens and in cells that were negative for the antigens. TIMP was also expressed predominantly along the synovial lining layer. In highly inflammatory RA, TIMP expression appeared less intense than that of the proteases. In osteoarthritic synovium, TIMP was expressed at easily detectable levels, whereas the expression of collagenase and stromelysin was less prominent. The balance between expression of the metalloproteinases and of the metalloproteinase inhibitor in synovium appears to be altered during inflammation. These results are consistent with the notion that synovium plays different roles in the cartilage damage of RA and of osteoarthritis.
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PMID:Expression of metalloproteinases and metalloproteinase inhibitor in human arthritic synovium. 165 8

Proteolytic enzymes, postulated to create an avenue for cell migration by digestion of host extracellular matrix molecules, have been implicated in neoplastic glial cell migration. A similar process is likely to occur in the developing brain. Fetal rabbit brain fragments transplanted into the striatum of the neonatal Shiverer mouse give rise to cells which migrate from the graft site and differentiate into astrocytes and oligodendrocytes. Proteinase expression by transplanted brain cells was studied using immunohistochemistry and in situ hybridization. Immature donor cells expressed the mRNAs for matrix metalloproteinases (MMP) 1 (collagenase) and 3 (stromelysin). Northern blot analysis of rabbit brain showed that MMP-1 in particular is expressed in the immature rabbit cerebrum and down-regulated during maturation. Immature donor cells exhibited immunoreactivity for urokinase plasminogen activator. However, immunoreactivity was also present in maturing neurons. Donor and host astroglia in the vicinity of grafts were immunoreactive for MMP-2 and tissue-type plasminogen activator. This expression may represent a reactive phenomenon, not specifically related to cell migration, by mature astrocytes. Based upon our findings, MMP-1 appears to be a candidate for involvement in migration of immature brain cells in the cerebrum.
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PMID:Expression of extracellular matrix degrading enzymes during migration of xenografted brain cells. 1019 76

Proteolysis occurs when proteinase activity exceeds inhibitor activity. Proteolysis is normally tightly regulated and is involved in cancer invasion and metastasis. The aim of this study was to compare proteolysis in breast and colorectal cancer. Proteinase and inhibitor expression were analysed in paired tumour and normal tissue samples from 43 breast and 24 colorectal cancer patients using substrate zymography, Western blotting and quenched fluorescence substrate hydrolysis. The expression of the latent forms of matrix metalloproteinase-2 (MMP-2), MMP-3 and MMP-9, urokinase plasminogen activator (uPA), tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 expression were observed in both tumour and normal tissue samples from breast and colorectal tissue; however, expression was greater in the tumour tissue. Expression of active MMP-2 and MMP-9 and the total MMP activity were greater in tumour compared to normal samples in both tissues (P < 0.05). The expression of all proteinases and total MMP activity was greater in colorectal tissue than breast tissue samples. Breast and colorectal cancer demonstrated different proteinase profiles, however proteolysis in both tissues was greater in tumour tissue than normal tissue.
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PMID:Proteolysis in human breast and colorectal cancer. 1049 54

Recent evidence indicates that protein aggregation and in particular the formation of toxic protein oligomers is a key mechanism in synucleinopathies such as Parkinson's disease (PD). Post mortem brain tissue studies as well as animal studies furthermore suggest that matrix metalloproteinases (MMPs) are also involved in the pathogenesis of PD. We used confocal single molecule spectroscopy to characterize the influence of MMPs and other proteases on the aggregation of alpha-synuclein. These studies were complemented by the characterization of alpha-synuclein fragment patterns generated by these proteases using gel electrophoresis and mass spectrometry. Limited digestion by MMP-1 and MMP-3, but not by MMP-9, increased the tendency of alpha-synuclein to aggregate. Proteinase K and Trypsin did not increase the level of de novo aggregation of alpha-synuclein. SDS-PAGE as well as MALDI-ToF analysis of limitedly digested alpha-synuclein demonstrate that all proteases generate different fragments of alpha-synuclein. We provide mass spectrometry data of proteolytic alpha-synuclein fragments and propose specific cleavage sites for MMP-1 and MMP-9 in alpha-synuclein. We furthermore found four additional cleavage sites of MMP-3 that had not been described previously. In order to increase aggregation of alpha-synuclein, specific cleavage between the highly charged C-terminal domain and the aggregation-prone NAC domain of alpha-synuclein seems to be crucial. Our findings obtained in vitro in a well-characterized model of pathological alpha-synuclein aggregation indicate that MMP-1 and MMP-3 may also influence pathogenesis of PD in vivo by generation of specific aggregation-enhancing alpha-synuclein fragments resulting from limited proteolysis.
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PMID:Increased alpha-synuclein aggregation following limited cleavage by certain matrix metalloproteinases. 1902 50

Matrix metalloproteinase (MMP)-9 (gelatinase B) participates in a variety of diverse physiologic and pathologic processes. We recently characterized a cyclooxygenase-2 (COX-2)-->PGE(2)-->EP4 receptor axis that regulates macrophage MMP-9 expression. In the present studies, we determined whether MMPs, commonly found in inflamed and neoplastic tissues, regulate this prostanoid-EP receptor axis leading to enhanced MMP-9 expression. Results demonstrate that exposure of murine peritoneal macrophages and RAW264.7 macrophages to MMP-1 (collagenase-1) or MMP-3 (stromelysin-1) lead to a marked increase in COX-2 expression, PGE(2) secretion, and subsequent induction of MMP-9 expression. Proteinase-induced MMP-9 expression was blocked in macrophages preincubated with the selective COX-2 inhibitor celecoxib or transfected with COX-2 small interfering RNA (siRNA). Likewise, proteinase-induced MMP-9 was blocked in macrophages preincubated with the EP4 antagonist ONO-AE3-208 or transfected with EP4 siRNA. Exposure of macrophages to MMP-1 and MMP-3 triggered the rapid release of TNF-alpha, which was blocked by MMP inhibitors. Furthermore, both COX-2 and MMP-9 expression were inhibited in macrophages preincubated with anti-TNF-alpha IgG or transfected with TNF-alpha siRNA. Thus, proteinase-induced MMP-9 expression by macrophages is dependent on the release of TNF-alpha, induction of COX-2 expression, and PGE(2) engagement of EP4. The ability of MMP-1 and MMP-3 to regulate macrophage secretion of PGE(2) and expression of MMP-9 defines a nexus between MMPs and prostanoids that is likely to play a role in the pathogenesis of chronic inflammatory diseases and cancer. These data also suggest that this nexus is targetable utilizing anti-TNF-alpha therapies and/or selective EP4 antagonists.
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PMID:Matrix metalloproteinase (MMP)-1 and MMP-3 induce macrophage MMP-9: evidence for the role of TNF-alpha and cyclooxygenase-2. 1992 55

Tauopathies such as Alzheimer's disease or progressive supranuclear palsy are characterized by pathological deposits of aggregated protein tau. It has been shown that truncated tau is present in these deposits, and it was thus hypothesized that truncation of the protein may play a role in pathological aggregation processes. Furthermore, recent findings indicate that pro-aggregatory extracellular tau can be taken up by neurons and induce neurodegeneration. In this study, we investigated the effect of limited proteolysis by matrix-metalloproteinases 3 and 9 (MMP-3, MMP-9) as well as by the proteinases trypsine and Proteinase K (PK) on tau aggregation behavior. We applied single molecule fluorescence techniques to monitor early tau oligomer formation at nanomolar protein concentrations. We observed that tau is a substrate of both MMP-3 and MMP-9, and show that limited proteolysis by MMP-9, but not by MMP-3, PK or trypsine, increases tau oligomer formation. We further characterize tau fragments resulting from limited cleavage, demonstrating a distinct cleavage pattern for both MMP-3 and MMP-9. In summary, our data demonstrate that tau is a substrate of both MMP-3 and MMP-9, and show a differential influence of these enzymes on tau aggregation behavior, implicating a potential role in neurodegeneration.
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PMID:Limited cleavage of tau with matrix-metalloproteinase MMP-9, but not MMP-3, enhances tau oligomer formation. 2289 Jan 15