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)

Serpins encompass a superfamily of proteinase inhibitors that regulate many of the serine proteinases involved in inflammation and hemostasis. In vitro, many serpins are catalytically inactivated by proteinases that they do not inhibit, leading to the concept of proteolytic down-regulation of serpin inhibitory capacity. The extent to which down-regulation of serpin activity occurs in vivo is debated, since little is known of the rates at which the process occurs. To address this debate, we have measured the rates of inactivation of three serpins, alpha 1-proteinase inhibitor (alpha 1PI), alpha 1-antichymotrypsin (alpha 1ACT), and antithrombin III (ATIII), by three human matrix metalloproteinases (MMPs-1, -2, and -3) thought to be involved in tissue destruction and repair. Our object was to establish a working kinetic model which can be used to predict whether serpin inactivation by these proteinases is likely to occur in vivo. We determined the rates of inactivation of these three serpins by each of the MMPs and compared these to rates of inhibition of the MMPs by an endogenous inhibitor, alpha 2-macroglobulin. An equation designed to predict the extent of substrate hydrolyzed by an enzyme in the presence of an enzyme inhibitor gave the following predictions of the inactivation in vivo: (i) ATIII is unlikely to be inactivated by the MMPs. (ii) MMP-2 (72-kDa gelatinase/type IV collagenase) is unlikely to inactivate any of the three serpins. (iii) MMP-1 (tissue collagenase) will inactivate alpha 1PI and alpha 1ACT only when its concentration saturates that of its controlling inhibitors. (iv) MMP-3 (stromelysin) may inactivate small amounts of alpha 1PI and more significant amounts of alpha 1ACT, even in the presence of its controlling inhibitors. Any physiologic or pathologic inactivation of these serpins by these MMPs that occurs in vivo will probably be due to MMP-3, and will likely only take place in tissues and inflammatory loci where the concentration of MMP inhibitors is depressed.
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PMID:Kinetics and physiologic relevance of the inactivation of alpha 1-proteinase inhibitor, alpha 1-antichymotrypsin, and antithrombin III by matrix metalloproteinases-1 (tissue collagenase), -2 (72-kDa gelatinase/type IV collagenase), and -3 (stromelysin). 165 20

1. Atherosclerosis and aneurysm of the abdominal aorta are associated with thinning of the medial connective tissue. We have investigated the presence of the connective-tissue-degrading metalloproteinases in homogenates prepared from atherosclerotic, aneurysmal and control aortic media. 2. Gelatinase activity was much increased in homogenates from atherosclerotic and aneurysmal aorta [10.9 +/- 1.8 and 13.3 +/- 3.3 micrograms of gelatin hydrolysed h-1 (mg of protein)-1 respectively]. This gelatinase activity was highest at the luminal aspect of the aortic media, where the activity increased three- to five-fold after the destruction of alpha 2-macroglobulin. Zymograms demonstrated the principal gelatinase in atherosclerotic aorta to have a molecular mass of about 92 kDa, whereas in aneurysmal aorta there was a spectrum of gelatinase activity from 92 to 55 kDa. 3. Collagenase and stromelysin (proteoglycanase) could be detected by immunoblotting in homogenates of aneurysmal aorta, but rarely in atherosclerotic aorta and never in control aorta. Collagenase and stromelysin activities were low, but increased two- to three-fold after the destruction of tissue inhibitor of metalloproteinases. Collagenase and stromelysin activities were highest at the adventitial aspect of aneurysmal media. 4. The secretion of gelatinase by inflammatory cells at the intima of diseased aorta could have a pathological role in establishing atherosclerotic plaques and medial thinning. Secretion of collagenase, gelatinase and stromelysin from the adventitia could accelerate connective tissue degradation in the media of aneurysmal aorta.
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PMID:Metalloproteinases in degenerative aortic disease. 165 68

Several N-carboxyalkyl peptides were synthesized and tested as inhibitors of pig synovial collagenase, 72-kDa gelatinase and stromelysin (matrix metalloproteinases MMP-1, MMP-2, and MMP-3). The most potent of the series, CH3CH2CH2(R,S)CH(COOH)-NH-Leu-Phe-Ala-NH2, competitively inhibited cleavage of dinitrophenyl-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH2 at the Gly-Leu bond by MMP-1 and MMP-2 (KI = 30 and 40 microM, respectively). A similar inhibitory potency was found for MMP-1 with soluble Type I collagen and MMP-3 with substance P as substrate. The inhibitor was coupled to EAH-Sepharose 4B through a C-terminal amide. In the presence of 2 M NaCl at pH 7.2, this matrix bound MMP-1, MMP-2, and MMP-3 from concentrated culture medium of pig synovial membranes. The enzymes coeluted at pH 4.1 and subsequently were resolved by chromatography on DEAE-Sephacel and heparin-Sepharose. Purified MMP-1 catalyzed the o-phenanthroline-sensitive cleavage of collagen into TCA and TCB fragments as well as slower hydrolysis of the alpha 2 chain. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of MMP-1 indicated a predominant polypeptide of approximately 44 kDa and minor species of approximately 24 and 21 kDa. The 44-kDa species and one of the smaller polypeptides reacted with an antiserum to residues 195-207 of human fibroblast MMP-1, indicating that porcine MMP-1 contains a similar sequence and that the smaller components were probably derived from MMP-1. Neither MMP-2 nor MMP-3 reacted with this antiserum. Purified porcine MMP-2 degraded gelatin but not collagen and exhibited an apparent Mr of approximately 71 kDa. Additional smaller polypeptides were present, one of which may correspond to tissue inhibitor of metalloproteinases. MMP-3 showed doublets of approximately 47/46 and 26/25 kDa and cleaved substance P at the Gly6-Phe7 bond. This procedure provides a rapid means of obtaining all three MMPs from one source in approximately 15% yield each.
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PMID:Application of N-carboxyalkyl peptides to the inhibition and affinity purification of the porcine matrix metalloproteinases collagenase, gelatinase, and stromelysin. 165 8

The mRNAs encoding 2 metalloproteinases, stromelysin 2 and collagenase I, have been detected by in situ hybridization in 26 carcinomas of the head and neck. 23 tumors of 26 expressed these mRNAs. Collagenase mRNAs were present in individual invasive cancer cells and in tumor cells at the periphery of poorly differentiated clusters (4 cases). Numerous stromal cells, principally fibroblasts were labeled (18 cases). Stromelysin mRNAs have been localized in tumor cells frequently arranged along disrupted basement membranes (8 cases). Many stromal cells in close contact to cancer cells also expressed the stromelysin mRNAs (17 cases). Normal residual cells were never labeled. These observations plead for the role of stromelysin produced by both stromal and tumor cells in the breakdown of basement membranes and the involvement of both collagenase and stromelysin in stromal invasion in carcinomas of the head and neck in vivo.
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PMID:Detection of mRNAs encoding collagenase I and stromelysin 2 in carcinomas of the head and neck by in situ hybridization. 165 73

The effects of several nonsteroidal antiinflammatory drugs, used at concentrations achievable in synovial fluid, on human osteoarthritic (OA) cartilage metallo-protease activity in vitro was studied. Acetaminophen and ketoprofen had no effect; sodium salicylate, indomethacin, and diclofenac slightly decreased proteoglycanase activity. Piroxicam and tenoxicam suppressed proteoglycanase activity by 48.2% and 68.3%, respectively, and suppressed collagenase activity by 19.1% and 36.8%, respectively. Use of these NSAIDs may help to decrease cartilage catabolism in patients with OA.
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PMID:In vitro effect of nonsteroidal antiinflammatory drugs on proteoglycanase and collagenase activity in human osteoarthritic cartilage. 165 6

Destructive joint changes in rheumatoid arthritis (RA) are thought to be mediated in part by the neutral proteinases collagenase and stromelysin. Collagenase messenger RNA (mRNA) has been previously localized to the synovial lining layer. In this study, synovial tissue from 8 patients with RA and 2 patients with osteoarthritis was examined for proteinase production by in situ hybridization. Stromelysin mRNA localized predominantly to the synovial lining layer cells. In serial sections, collagenase mRNA was shown to be localized to the same tissue areas as those producing stromelysin mRNA, and grain counts revealed a direct correlation between production of stromelysin mRNA and production of collagenase mRNA. All patients with RA were producing collagenase and stromelysin mRNA in detectable amounts. One of 2 osteoarthritis patients was producing these metalloproteinases, but in levels below those found in the RA patients. These data support the identity of the synovial lining cells as the major synovial cells producing collagenase and stromelysin in RA and provide new evidence for the coordinate production of collagenase and stromelysin in RA in vivo.
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PMID:In situ hybridization studies of stromelysin and collagenase messenger RNA expression in rheumatoid synovium. 165 7

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

Chondrocyte-derived metalloproteases have been postulated to play a role in the degradation of articular cartilage during the development of chronic arthritic disorders. TNF alpha (tumor necrosis factor alpha), an inflammatory mediator released by activated macrophages, has been detected in the synovial fluid of patients with rheumatoid diseases. We have found that TNF alpha is a potent stimulator of collagenase and stromelysin mRNA accumulation, collagenase activity, and immunoprecipitable stromelysin in monolayer cultures of adult porcine articular chondrocytes. In contrast EGF (epidermal growth factor), which stimulates collagenase and/or stromelysin synthesis in fibroblast systems, stimulated minimal amounts of these enzymes at both the message and protein levels. Nuclear run-on transcription analysis demonstrated that the TNF alpha-stimulated increase in stromelysin and collagenase message levels was, at least partially, due to increased transcription. Elevated transcription of these genes, in response to TNF alpha, was apparent by at least 2 hours post-stimulation. The degree of c-fos and c-jun stimulation by TNF alpha or EGF did not correlate with the levels of collagenase and stromelysin message stimulated by these factors. EGF stimulated significant accumulation of both c-fos and c-jun mRNAs while only very low amounts of these messages were stimulated by TNF alpha. Our data suggests that TNF alpha may contribute to articular cartilage degradation by stimulating chondrocyte-derived matrix metalloproteases. In addition the regulation of metalloprotease genes in chondrocytes may be different from their regulation in fibroblasts.
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PMID:Tumor necrosis factor alpha and epidermal growth factor regulation of collagenase and stromelysin in adult porcine articular chondrocytes. 165 9

Synovial fibroblasts freshly isolated from the rheumatoid joint are characterized by their marked connective tissue degradative ability. This phenotype includes the ability to secrete large amounts of the matrix-degrading metalloproteinases, collagenase, and stromelysin. We have found that another aspect of this phenotype is the constitutive expression at both protein and mRNA levels of a 92-kD gelatinolytic metalloproteinase, which is not secreted by normal dermal or lung fibroblasts and is immunologically cross-reactive with a type V collagenase expressed by activated macrophages and neutrophils. Expression of this 92-kD metalloproteinase confers upon the fibroblasts the capacity to degrade collagenase- and stromelysin-resistant interstitial elements, such as collagen types IV, V and XI. In contrast to the 92-kD metalloproteinase, a 68-kD gelatinase (type IV collagenase) was expressed by all fibroblast types studied, indicating that its regulation is distinct from that of the 92-kD gelatinase. To identify what cytokines may be important in the induction of the rheumatoid synovial phenotype, including expression of the 92-kD gelatinase, we exposed normal dermal fibroblasts to a number of cytokines including many known or considered likely to be present in rheumatoid synovial fluid and tissue. Although IL-1 beta, tumor necrosis factor-alpha, lymphotoxin, platelet-derived growth factor, and basic fibroblast growth factor were capable of stimulating fibroblasts to secrete collagenase, only tumor necrosis factor-alpha, lymphotoxin, and IL-1 beta were able to induce expression of the 92-kD gelatinase, demonstrating discordant regulation of the two metalloproteinases. Expression of the 68-kD gelatinase was independent of that of the 92-kD gelatinase, as demonstrated at the protein and mRNA levels. Late passage rheumatoid synovial fibroblasts, which no longer constitutively expressed the 92-kD gelatinase, displayed an accentuated response to IL-1 beta when compared to normal dermal fibroblasts. Thus, in addition to IL-1 beta, tumor necrosis factor-alpha or lymphotoxin may contribute to the expression of a specific rheumatoid synovial phenotype in vivo that is associated with progressive matrix destruction.
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PMID:Constitutive expression of a 92-kD gelatinase (type V collagenase) by rheumatoid synovial fibroblasts and its induction in normal human fibroblasts by inflammatory cytokines. 165 48

The action of purified rabbit bone stromelysin was investigated on proteoglycan aggregates from pig laryngeal cartilage. The enzyme caused a rapid fall in viscosity of proteoglycan aggregate solution (6 mg/ml), and the products of a partial digest (60% loss of relative viscosity) and a complete digest (95% loss of relative viscosity) were characterized. Analysis by gel chromatography on Sepharose 2B under associative conditions showed that 95% of the glycosaminoglycans in the complete digest were in small-sized fragments, whereas most of the hyaluronan-binding G1 domain and link protein remained intact and bound to hyaluronan. In contrast, there was extensive digestion of the G2 domain which resulted in 76% loss in its detection by immunoassay. Analysis of the partial digest also showed considerable loss (40%) of detection of the G2 domain, but the glycosaminoglycan-rich fragments were much larger than in the complete digest. There was also much less cleavage to create small fragments containing the G1 domain. This was evident on SDS/PAGE analysis where a 58 kDa G1 domain fragment was abundant in the complete digest, but was only present in small amounts in the partial digest. There was also only very limited conversion of link protein from a 44 kDa form to a 40 kDa form. The digestion of proteoglycan aggregate (6 mg/ml) by stromelysin was unaffected by the addition of a high concentration of extra chondroitin sulphate chains (14 mg/ml), and the digestion of proteoglycan monomer showed that the G1 domain was resistant to stromelysin digestion even when not bound to hyaluronan and link protein. The results show that stromelysin degrades the proteoglycan protein core with major cleavages close to, but not within, the G1 domain, and extensive cleavage in other regions. Experiments with purified collagenase, a metalloproteinase structurally related to stromelysin, showed that it too cleaved proteoglycan at several sites within the glycosaminoglycan-rich region of the core protein. Metalloproteinase attack on proteoglycan thus not only occurs with stromelysin but also with collagenase.
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PMID:Metalloproteinase digestion of cartilage proteoglycan. Pattern of cleavage by stromelysin and susceptibility to collagenase. 165 87


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