Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mast cell activation in vivo is often associated with areas of oedema and connective-tissue degradation. Tryptase and chymase are the major serine proteinases released by mast cells, but they appear to have little activity on most components of the extracellular matrix. The matrix metalloproteinases (MMP) are purported to degrade almost all connective tissue elements and are secreted by cells in the form of inactive precursors. Since the mechanisms of MMP activation in vivo are poorly understood we have examined the potential of mast cell proteinases to activate the precursor forms of human collagenase (MMP-1), stromelysin (MMP-3), gelatinase A (MMP-2) and gelatinase B (MMP-9). Mast cell proteinases prepared from purified dog mastocytoma cells were shown to process and activate purified precursor forms of both MMP-1 and MMP-3. Using antipain and chymostatin, inhibitors for tryptase and chymase, respectively, it was demonstrated that both pMMP-1 and pMMP-3 were effectively processed and activated by the chymase component. By contrast, tryptase activated only pMMP-3. The mast cell proteinases were unable to process or activate purified precursor forms of MMP-2 and MMP-9. However, MMP-3 previously activated by mast cell proteinases was shown to activate pMMP-9, but not pMMP-2. Since we have no evidence that mast cells express these four metalloenzymes, the release of mast cell serine proteinases following activation/degranulation could contribute to local metalloproteinase activation and subsequent matrix degradation.
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PMID:Mast cell proteinases activate precursor forms of collagenase and stromelysin, but not of gelatinases A and B. 803 91

We have explored the tissue localization of extracellular matrix metalloproteinases MMP-1 (fibroblast collagenase), MMP-2 (72-kDa gelatinase/Type IV collagenase), MMP-3 (stromelysin), MMP-8 (polymorphonuclear leukocyte collagenase) and MMP-9 (92-kDa gelatinase/Type IV collagenase) in the tissues around loose hip prostheses. The findings were compared with those in synovial tissues obtained from patients with a fractured femoral neck. MMP-type specific antisera were applied in the sensitive avidin-biotin-peroxidase complex methods. MMP-1 was found in monocyte/macrophages, fibroblasts, and vascular endothelial cells in both interface tissues between bone and acetabular components and the pseudocapsular tissues obtained from loosening of hip prostheses. In these tissues, MMP-8 was occasionally found, but only in polymorphonuclear leukocytes. Cells showing immunoreactivity to 72- and 92-kDa gelatinase/Type IV collagenase, MMP-2 and MMP-9, respectively, and stromelysin, MMP-3, were abundant in both interface and pseudocapsular tissues in loose hip prostheses. In contrast, in hip fractures, immunoreactivity to MMP-1, 2, 3, and 9 was weak and only observed in synovial tissues. Immunoreactivity to MMP-8 was confined to polymorphonuclear leukocytes attached to the synovial membrane or in the infiltrate around blood vessels in the subsynovial connective tissues. The finding of MMP-1, 2, 3, and 9 in the tissues around loose hip prostheses suggests that they play a role in the weakening of connective tissues, and this leads to loosening.
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PMID:Extracellular matrix metalloproteinases around loose total hip prostheses. 804 79

The purpose of this study was to determine how interferons alpha and gamma influence the expression of M(r) 72,000 type-IV collagenase (gelatinase A) and M(r) 92,000 type-VI collagenase (gelatinase B) genes and whether there are differences in their gene expression. Special emphasis was focused on the treatment time. Total cellular RNA from A2058 human melanoma cells treated for various time periods with IFN-alpha or gamma was analyzed by Northern- and slot-blot hybridization. Both M(r) 72,000 and M(r) 92,000 type-IV collagenase mRNAs were detectable in A2058 cells and mRNA levels for both gelatinases were significantly up-regulated in the cells treated for a short time period with either IFN-alpha or gamma. In contrast, a long-term treatment (7 days) with these drugs markedly down-regulated the genes for both gelatinase A and B. Zymographic analysis showed that human melanoma primarily secretes the gelatinase-A activity, which showed changes similar to those seen in the corresponding mRNA after the treatments with interferons. The expression of gelatinase-B activity was, however, detectable only transiently during the stimulating phase with IFN-alpha. Western immunoblot analysis showed that alterations in the levels of immunoreactive protein of gelatinase A in the cells correlated with the mRNA levels after the treatments. These findings suggest that IFN-alpha and IFN-gamma are potent regulators of both M(r) 72,000 and M(r) 92,000 type-IV collagenase/gelatinase A and B genes in human melanoma showing biphasic and parallel effects on mRNA levels of both enzymes, depending on the treatment time, and that the M(r) 72,000 metalloproteinase/gelatinase A is the predominant basement-membrane-degrading type-IV collagenase in human melanoma.
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PMID:Modulation of M(r) 72,000 and M(r) 92,000 type-IV collagenase (gelatinase A and B) gene expression by interferons alpha and gamma in human melanoma. 805 55

Members of the matrix metalloproteinase (MMP) family have been implicated in disease states such as arthritis, periodontal disease, and tumor cell invasion and metastasis. Stromelysin 1 (MMP-3) has a broad substrate specificity and participates in the activation of several MMP zymogens. We examined known sequences of MMP-3 cleavage sites in natural peptides and proteins and compared sequence specificities of MMP-3 and interstitial collagenase (MMP-1) in order to design fluorogenic substrates that (i) would be hydrolyzed rapidly by MMP-3, (ii) would discriminate between MMP-3 and MMP-1, and (iii) could be monitored continuously without interference from MMP amino acid residues. Designed substrates were then screened for activity toward MMP-1, gelatinase A (MMP-2), MMP-3, and gelatinase B (MMP-9). The first of these substrates, NFF-1 (Mca-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Lys-(Dnp)-Gly, where Mca is (7-methoxycoumarin-4-yl)acetyl and Dnp is 2,4-dinitrophenyl), was hydrolyzed equally well by MMP-3 and MMP-2 (kcat/Km approximately 11,000 s-1 M-1). MMP-1 had 25% of the activity of MMP-3 toward NFF-1. The second substrate, NFF-2 (Mca-Arg-Pro-Lys-Pro-Tyr-Ala-Nva-Trp-Met-Lys(Dnp)-NH2, where Nva is norvaline), was hydrolyzed 60 times more rapidly by MMP-3 (kcat/Km = 59,400 s-1 M-1) than MMP-1. Unfortunately, NFF-2 showed little discrimination between MMP-3, MMP-2 (kcat/Km = 54,000 s-1 M-1), and MMP-9 (kcat/Km = 55,300 s-1 M-1). The third substrate, NFF-3 (Mca-Arg-Pro-Lys-Pro-Val-Glu-Nva-Trp-Arg-Lys(Dnp)-NH2), was hydrolyzed rapidly by MMP-3 (kcat/Km = 218,000 s-1 M-1) and very slowly by MMP-9 (kcat/Km = 10,100 s-1 M-1), but there was no significant hydrolysis by MMP-1 and MMP-2. NFF-3 is the first documented synthetic substrate hydrolyzed by only certain members of the MMP family and thus has important application for the discrimination of MMP-3 activity from that of other MMPs. Although NFF-3 was designed by assuming that substrate subsites were independent and hence free energy changes derived from single mutation experiments were additive, we found discrepancies between predicted and experimental kcat/Km values, one on the order of 2000-5000. Thus, the design of additional discriminatory MMP substrates may require approaches other than assuming additive free energy changes, such as screening synthetic libraries and consideration of secondary and tertiary structures of substrates and the enzyme.
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PMID:Design and characterization of a fluorogenic substrate selectively hydrolyzed by stromelysin 1 (matrix metalloproteinase-3). 806 13

The metalloproteinase matrilysin is widely expressed in the epithelial tumor cells of malignant colorectal adenocarcinomas. Approximately 50% of benign adenomas also express low levels of matrilysin that is focally localized. The expression of stromelysin-1, stromelysin-3, and gelatinase A was observed in the stromal component of several carcinomas and was not present in adenomatous tissue. The expression of interstitial collagenase and gelatinase B was observed in occasional adenomas and carcinomas. Stromelysin-2 transcripts were not detectable in any of the samples examined. Tissue inhibitor of metalloproteinase-1 gene expression was widespread and was observed in both epithelial and stromal cells of adenomas and carcinomas. These results indicate that matrilysin gene expression is an early event in colorectal tumorigenesis and that the expression of stromelysin-1, stromelysin-3, and gelatinase A is primarily a late event. The observed gene expression patterns suggest that matrilysin may participate in early events in tumor progression and that multiple members of the metalloproteinase family may work in concert to facilitate late-stage tumor invasion and metastasis.
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PMID:Expression and localization of matrix-degrading metalloproteinases during colorectal tumorigenesis. 806 80

The process of wound healing sets in motion a complex and dynamic series of events, which includes the remodeling of the extracellular matrix. Degradation of matrix macromolecules is mediated through the actions of the matrix metalloproteinase family. Conversely, the actions of this enzyme family are regulated by tissue inhibitors of metalloproteinases (TIMPs). In this study, we have developed riboprobes derived from human cDNAs representing collagenase, 72-kDa gelatinase, and TIMP and have found them to be sufficiently specific and sensitive for use in in situ hybridization studies of porcine burn wounds. Expression of these mRNAs, although not seen in uninjured skin, was found to be a predictable and locally distinct event in wound repair. Transcripts for collagenase and TIMP but not 72-kDa gelatinase were detected at the resurfacing epithelial margin; label was also detected in and around follicular epithelium within the wound bed. Transcripts for both metalloenzymes and TIMP were found throughout the viable dermis and subcutaneous tissues underlying the wound bed. However, expression of 72-kDa gelatinase was most prominent in the superficial dermis adjacent to the resurfacing epidermis at the wound margin. Collagenase and TIMP transcripts were particularly prominent in a perivascular pattern in the dermis and in the connective tissue network surrounding adipocytes in the subcutaneous zone. Numerous cell types appeared to be involved, including keratinocytes, fibroblasts, macrophages, and endothelial cells. Future exploitation of this porcine thermal injury model is likely to provide information about the spatial and temporal patterns of matrix metalloproteinase and TIMP expression in cutaneous wound healing.
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PMID:Localization of mRNAs representing interstitial collagenase, 72-kda gelatinase, and TIMP in healing porcine burn wounds. 807

Macrophages represent a critical component in the inflammatory lesions of giant cell arteritis. By combining immunohistochemistry and in situ hybridization, we have analyzed the functional heterogeneity of tissue-infiltrating macrophages in patients with untreated vasculitis. 20% of macrophages in temporal artery tissue synthesized IL-6-specific mRNA and produced IL-6 and IL-1 beta proteins. IL-6 and IL-1 beta production was not limited to CD68+ cells in the lymphoid aggregates but was a feature of CD68+ cells dispersed throughout the tissue. 50% of tissue-infiltrating CD68+ cells synthesized 72-kD type IV collagenase. Only a small subset of CD68+ cells produced cytokines as well as collagenase, indicating functional specialization or distinct differentiation stages of CD68+ cells in the inflamed tissue. Activation of CD68+ cells was not restricted to tissue-infiltrating cells. Expression of IL-6 and IL-1 beta was found in 60-80% of circulating monocytes of patients with untreated giant cell arteritis, whereas collagenase production was restricted to tissue macrophages. IL-6 and IL-1 beta production by the majority of circulating monocytes was a shared feature of patients with giant cell arteritis and polymyalgia rheumatica but was not found in rheumatoid arthritis. These data suggest that giant cell arteritis has two components of disease, an inflammatory reaction in vessel walls and a systemic activation of monocytes. Systemic monocyte activation can manifest independently without vasculitis as exemplified in patients with polymyalgia rheumatica.
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PMID:Functional profile of tissue-infiltrating and circulating CD68+ cells in giant cell arteritis. Evidence for two components of the disease. 808 54

Chondrosarcoma was found to produce a heat-labile collagenase and a heat-stable collagenase inhibitor. Unlike its cartilage counterpart, the inhibitory activity in chondrosarcoma could only be detected after heat-treatment. Western blot analysis of chondrosarcoma-derived inhibitor showed that this inhibitor cross-reacted with a polyclonal antibody raised against purified cartilage-derived collagenase inhibitor (1) at a M.W. of about 33 kDa. In addition to the collagenase activity, which appears to be matrix metalloproteinase I (MMP-1), chondrosarcoma extracts were shown to contain four active gelatinase species which migrate at a molecular weight consistent with that reported for MMP-2 (72 kDa gelatinase, Type IV gelatinase) (2) and three active enzyme species which migrate at a molecular weight consistent with that reported for MMP-9 (92 kDa gelatinase, Type IV gelatinase) (3,4). In contrast, normal cartilage contained only two active and one latent form of MMP-2 in significantly lower amounts than in chondrosarcoma. In the case of MMP-9, the same three species were present in normal cartilage and in chondrosarcoma, but in lower amounts in the normal tissue. These results suggest that chondrosarcoma might develop in vivo because the inherent proteolytic balance between the protease(s) and its endogenous inhibitor(s) is shifted in favor of the enzyme.
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PMID:Production of matrix metalloproteinases and a metalloproteinase inhibitor by swarm rat chondrosarcoma. 812 44

Linoleic acid (LA), an omega-6 fatty acid, enhanced the appearance of type IV collagenase activity in culture medium conditioned by the metastatic MDA-MB-435 human breast cancer cell line; this effect was maximal with 0.75 microgram/ml LA. Zymography showed an increase in the gelatinolytic 92 kDa metalloproteinase, a form associated with the metastatic phenotype, during culture in the presence of 0.75 microgram/ml LA. Indomethacin, 20 micrograms/ml, completely suppressed the stimulation of collagenase by LA, suggesting a role for the eicosanoids. The tumor cells expressed mRNA for both the 72 and 92 kDa isoforms of type IV collagenase. Basal levels of the 92 kDa mRNA were much higher; both were up-regulated by LA despite the absence of detectable 72 kDa activity in conditioned medium.
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PMID:Stimulation of type IV collagenase expression by linoleic acid in a metastatic human breast cancer cell line. 812 68

Altered degradation of extracellular matrix has been implicated in the pathogenesis of hepatic fibrosis. We investigated levels and cellular sites of gene expression of two major collagen-degrading enzymes, matrix-metalloproteinase (MMP)-1 (fibroblast type-interstitial collagenase) and MMP-2 (72-kd gelatinase, type IV collagenase) in five normal and 18 fibrotic human livers as well as in cultured human hepatic fat-storing cells by Northern blot analysis and in situ hybridization. Fat-storing cells expressed both MMP-1 and MMP-2 RNA in vitro. In vivo, MMP-1 was undetectable in mesenchymal and parenchymal cells of all liver specimens, whereas MMP-2 transcripts were expressed in all livers by vimentin-positive, CD68-negative mesenchymal cells. Mesenchymal cells of all fibrotic livers displayed high transcript levels of transforming growth factor-beta 1, which is known to modulate MMP expression. Along with de novo fibrogenesis and possibly influenced by transforming growth factor-beta 1, expression of MMP-2 in the absence of MMP-1 expression may be responsible for the quantitative and qualitative changes of extracellular matrix observed in chronic liver disease.
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PMID:Differential expression of matrix-metalloproteinase-1 and -2 genes in normal and fibrotic human liver. 812 38


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