Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We attempted to study the possible relationships between neutrophil-type procollagenase/pro-matrix metalloproteinase (MMP-8) and the serine proteinases plasmin, cathepsin G and tryptase in bronchiectasis. The presence of the plasmin/plasminogen system and plasmin-, cathepsin G- and tryptase-like activities were compared to the activity of endogenously activated MMP-8 in bronchoalveolar lavage (BAL) fluid in 38 bronchiectasis patients and in 14 healthy controls by means of immunohistochemistry, Western-blot and substrate-based functional assays. In contrast to cathepsin G- and tryptase-like activities, the plasmin/plasminogen activator system in BAL fluid was observed to have a relatively weak activation stage and no correlation with disease severity. Neither plasmin-like activities nor concentrations of plasminogen activators from the bronchiectatic patients differed significantly from the values of healthy controls. Immunolocation of plasminogen activator inhibitor-1 showed a marked, but not significant, increase in bronchiectatic lung as compared to controls. In contrast to cathepsin G- and tryptase-like activities, with their strong and significant correlation with endogenously activated collagenase (r=0.9; p=0.0001; and r=0.6; p=0.03, respectively), no correlations were observed between plasmin-like and endogenously activated collagenase (r=0.3; p=0.2) in bronchiectasis. These findings suggest that cathepsin G- and tryptase-like activities may act as potent pro-matrix metalloproteinase-8 activators in patients with bronchiectasis, whereas the plasminogen activator/plasmin cascade was shown to be down-regulated.
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PMID:Potentiative effects of neutral proteinases in an inflamed lung: relationship of neutrophil procollagenase (proMMP-8) to plasmin, cathepsin G and tryptase in bronchiectasis in vivo. 949 62

To study the mechanism of collagen degradation by keratocytes, we developed the new in vitro model in which keratocytes were cultured three-dimensionally in a collagen matrix. Subcultured rabbit keratocytes were embedded in a type I collagen matrix and cultured in serum-free medium. Collagenolytic activity of the cells was determined by measuring the amount of hydroxyproline released into the medium from degraded collagen. Activities of collagenase in the medium were also measured, using collagen labeled with fluorescein isothiocyanate as a substrate. The presence of plasminogen was required for collagen degradation by keratocytes. In the presence of plasminogen, the amount of collagen degradation depended on both the cultivation period and the number of cells. The addition of interleukin-1 (IL-1) stimulated the collagen degradation in a dose-dependent manner. This stimulatory effect of IL-1 was completely inhibited by the addition of IL-1 receptor antagonist (IL-1ra). Collagenase activity in the medium was stimulated by the addition of IL-1, and IL-1ra antagonized this stimulatory effect. These findings indicate that our present model may be useful for investigating the mechanism of collagen degradation by keratocytes.
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PMID:Collagenolytic activity of keratocytes cultured in a collagen matrix. 958 37

To determine whether matrix metalloproteinase-1 (MMP-1) or MMP-3 is involved in cartilage collagen degradation, polyclonal antibodies were separately raised against MMP-1 and MMP-3 and their effects on collagen degradation were assessed in rabbit cartilage explant culture. We found that anti-MMP-1 antibodies completely inhibited collagen degradation induced by the combination of interleukin-1 (IL-1) and plasminogen. Anti-MMP-3 antibodies showed 40% inhibition at maximum concentration. These results indicate that MMP-1, and possibly MMP-3, are involved in collagen degradation in cartilage explant culture.
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PMID:Involvement of MMP-1 and MMP-3 in collagen degradation induced by IL-1 in rabbit cartilage explant culture. 962 8

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play a significant role in regulating angiogenesis, the process of new blood vessel formation. Interstitial collagenase (MMP-1), 72 kDa gelatinase A/type IV collagenase (MMP-2), and 92 kDa gelatinase B/type IV collagenase (MMP-9) dissolve extracellular matrix (ECM) and may initiate and promote angiogenesis. TIMP-1, TIMP-2, TIMP-3, and possibly, TIMP-4 inhibit neovascularization. A new paradigm is emerging that matrilysin (MMP-7), MMP-9, and metalloelastase (MMP-12) may block angiogenesis by converting plasminogen to angiostatin, which is one of the most potent angiogenesis antagonists. MMPs and TIMPs play a complex role in regulating angiogenesis. An understanding of the biochemical and cellular pathways and mechanisms of angiogenesis will provide important information to allow the control of angiogenesis, e.g. the stimulation of angiogenesis for coronary collateral circulation formation; while the inhibition for treating arthritis and cancer.
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PMID:Complex role of matrix metalloproteinases in angiogenesis. 979 30

Normal as well as neoplastic cells traverse extracellular matrix barriers by mobilizing proteolytic enzymes in response to epidermal growth factor (EGF)-EGF receptor (EGFR) or hepatocyte growth factor/scatter factor (SF)-c-Met interactions. The plasminogen activator-plasminogen axis has been proposed to play a key role during cell invasion, but the normal development of plasminogen activator- as well as that of plasminogen-deficient mice supports the existence of alternate proteolytic systems that permit cells to traverse extracellular matrix barriers. To characterize the role that matrix-degrading proteinases play in EGF- or SF-stimulated invasion, a human squamous carcinoma cell line (UM-SCC-1) was triggered atop the matrices of type I collagen or human dermal explants in a three-dimensional culture system. During EGF- or SF-induced invasion, UM-SCC-1 cells expressed urokinase-type plasminogen activator (uPA) and uPA receptor as well as the matrix metalloproteinases (MMPs), membrane-type MMP-1, collagenase 1, stromelysin 1, and gelatinase B. Despite the presence of a positive correlation between uPA receptor-uPA expression and growth factor-stimulated invasion, UM-SCC-1 invasion was not affected by inhibitors directed against the plasminogen activator-plasminogen axis. In contrast, both recombinant and synthetic MMP inhibitors completely suppressed invasion by either EGF- or SF-stimulated cells without affecting either proteinase expression or cell motility across collagen-coated surfaces. These data demonstrate that MMPs, but not the plasminogen activator-plasmin system, can directly regulate the ability of either EGF- or SF-stimulated tumor cells to invade interstitial matrix barriers.
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PMID:Role of the plasminogen activator and matrix metalloproteinase systems in epidermal growth factor- and scatter factor-stimulated invasion of carcinoma cells. 982 36

Accumulation of the glomerular extracellular matrix (ECM) is a pivotal event in the progression from acute glomerular injury to end-stage renal disease. Although enhanced ECM synthesis has been demonstrated to contribute to ECM accumulation, the role of decreased ECM degradation is largely unknown. It was previously shown that glomerular ECM degradation is mediated by a plasminogen activator (PA)/plasmin/matrix metalloproteinase 2 (MMP-2) cascade. However, little information is available regarding the factors that regulate the activity of this degradative cascade in normal or pathologic states. Transforming growth factor-beta1 (TGF-beta1) is shown here to be a potent inhibitor of ECM degradation by cultured human mesangial cells. Using human mesangial cells grown on thin films of 125I-labeled Matrigel, dose-dependent inhibition of ECM degradation in the presence of TGF-beta1 was observed, reaching >90% inhibition with 0.4 ng/ml TGF-beta1. Addition of anti-TGF-beta antibodies (4 microg/ml) in the absence of exogenous TGF-beta increased ECM degradation (1.8+/-0.2-fold versus controls, P<0.05). In contrast, platelet-derived growth factor, at concentrations up to 10 ng/ml, had no effect on ECM degradation. TGF-beta completely blocked the conversion of plasminogen to plasmin and markedly reduced the conversion of latent MMP-2 to active MMP-2. TGF-beta did not significantly alter the levels of tissue PA, total MMP-2, or tissue inhibitor of metalloproteinase-1, but did increase the levels of PA inhibitor- (1.8-fold, P<0.05), the major physiologic inhibitor of PA. These data document that TGF-beta is a potent inhibitor of ECM degradation by cultured human mesangial cells, and they suggest that decreased mesangial matrix degradation, caused by TGF-beta-mediated decreases in the activity of the PA/plasmin/MMP-2 cascade, may contribute to the glomerular matrix accumulation that occurs in progressive renal disease.
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PMID:Transforming growth factor-beta is a potent inhibitor of extracellular matrix degradation by cultured human mesangial cells. 1020 63

We investigated the inhibitory action of a synthetic peptidyl hydroxamate inhibitor of matrix metalloproteinase (MMP), Galardin (GM6001), on collagen degradation by rabbit corneal stromal fibroblasts (keratocytes) cultured three-dimensionally in the type I collagen gel with medium containing interleukin 1alpha (IL-1alpha) and/or plasminogen. Degradation of collagen fibrils during culture was measured by the release of hydroxyproline, and activation of MMPs was also analyzed by gelatin zymography and Western blotting. Plasmin activity was measured using a synthetic substrate. In the absence of plasminogen, treatment of the cells with IL-1alpha in collagen gel greatly enhanced the production of proMMP-1, -3 and -9, but no significant degradation of collagen was detected. In the presence of plasminogen, IL-1alpha stimulated collagen degradation by keratocytes in a dose-dependent manner. This resulted from the plasminogen activator-plasmin system-dependent activation of proMMP-1, -3 and -9. Galardin inhibited the collagen degradation in a dose-dependent fashion in the presence of plasminogen, whether IL-1alpha was present or not. Galardin inhibited the activation of proMMP-3, and also prevented the activation of proMMP-9 and the conversion of MMP-1 intermediates to the fully active MMP-1. Galardin did not affect plasmin activity. The present results suggest that Galardin inhibits IL-1alpha-stimulated collagen degradation in the presence of plasminogen, resulting from not only inhibiting active MMPs but also preventing the conversion of proMMPs to active MMPs.
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PMID:Galardin inhibits collagen degradation by rabbit keratocytes by inhibiting the activation of pro-matrix metalloproteinases. 1032 70

During progesterone-induced decidualization of estradiol (E2)-primed human endometrial stromal cells (HESCs), the interstitial-type extracellular matrix (ECM) of the follicular phase endometrium is transformed in the luteal phase to a mixture of residual interstitial- and new basal laminar-type components. This transformation is accelerated by reduced proteolytic activity of HESCs undergoing decidualization (DZ). In cultured HESCs, progestins, but not E2, induce the expression of several DZ markers, and E2 enhances these effects despite the lack of response to E2 alone. Using this well-characterized in vitro DZ model we evaluated the expression of plasminogen activators (PAs), which degrade ECM components that undergo rapid turnover, and matrix metalloproteinases (MMPs), which degrade the bulk of ECM components. Medroxyprogesterone acetate (MPA) inhibited the catalytic activity of urokinase-type PA (uPA) and tissue-type PA (tPA) as well as the expression of such MMPs as interstitial collagenase (MMP-1) and stromelysin-1 (MMP-3). Moreover, E2 + MPA elicited greater inhibitory effects on the expression of all of these proteases. Progestin inhibition of PA activities reflected reciprocal upregulation in the output of the PA inhibitor PAI-1, which produced large molar excesses of PAI-1 compared with the PAs in HESC-conditioned medium. By contrast, the tissue inhibitor of the MMPs, TIMP1, as well as gelatinase A (MMP-2), was constitutively expressed by the HESCs. In the absence of implantation, menstruation-associated degradation of the functional endometrial ECM is triggered by withdrawal of circulating ovarian steroids. This process was evaluated in cultured HESCs that were first decidualized during 10 days of exposure to E2 + MPA, and then withdrawn to steroid-free medium with and without the antiprogestin RU 486. As expected, steroid withdrawal reversed progestin-inhibited PA activity as well as the expression of MMP-1 and MMP-3 and progestin-enhanced PAI-1; much greater reversal was observed in medium supplemented with RU 486. Unlike the changes in PAI-1, neither TIMP1, nor MMP-2 expression was affected by withdrawal to steroid-free or to RU 486-medium. By altering the composition of the ECM of the luteal phase endometrium, progestin-elicited inhibition of the PAs, uPA and tPA, as well as that of the MMPs, MMP-1 and MMP-3, modulates trophoblast adhesion, migration and differentiation. Conversely, steroid withdrawal elicited increases in uPA, MMP-1 and MMP-3 activities would promote endometrial sloughing by degrading the mixture of decidual cell-derived basement membrane-like proteins and interstitial components that comprise the stromal ECM of the perimenstrual endometrium.
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PMID:Implications of decidualization-associated protease expression in implantation and menstruation. 1040 70

Glucocorticoids ameliorate erosion in animal osteoarthritis (OA) models and suppress synthesis of matrix metalloproteinases (MMP). However, in in vitro studies, their inhibitory effects on matrix degradation of cartilage have not been well documented by monitoring aggrecan. Collagen was monitored in this study to examine the effects of dexamethasone in cartilage explant culture. Dexamethasone clearly blocked collagen degradation induced by the combination of interleukin-1 (IL-1) and plasminogen at the concentration of 10(-9) M, which is much lower than the concentrations reportedly required to inhibit matrix synthesis. In addition, MMP-1 and MMP-3 were suppressed by dexamethasone treatment in a similar range of concentrations. The conversion of plasminogen to plasmin, however, was not blocked by treatment with dexamethasone. These results suggest that the inhibitory effect of dexamethasone on collagen degradation may be due to suppression of MMP production rather than suppression of fibrinolytic cascade. Thus, the ability of glucocorticoids to inhibit matrix degradation in vitro, which could be clearly shown by monitoring collagen degradation, may endorse their efficacy in animal OA models and suggest potential therapeutic effectiveness.
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PMID:Dexamethasone inhibits collagen degradation induced by the combination of interleukin-1 and plasminogen in cartilage explant culture. 1044 72

Plasmin, the enzymatically active form of plasminogen, can activate several matrix metalloproteinases (MMPs). In this study, we investigated the activation of MMP-1, one of the major interstitial collagenases, by plasmin which was generated on the surface of Staphylococcus aureus cells. Plasmin bound to plasminogen receptors on S. aureus degraded the major (125)I-labeled 55-kDa proMMP-1 into the 42-kDa form corresponding to the size of active MMP-1. MMP-1 formed by S. aureus-bound plasmin was also enzymatically active as judged by digestion of the synthetic collagenase substrate, DNP-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH(2). The finding that, in MMP-1 molecules generated either by soluble plasmin or by S. aureus-bound plasmin, the amino-terminal amino acid sequences were identical indicated that the activation mechanisms of the two plasmin forms do not differ from each other. The present observations emphasise and broaden the physiological importance of bacterial plasminogen receptors. In addition to direct proteolytic effects on components of the extracellular matrix, receptor-bound plasmin is also capable of initiating an MMP-1-dependent matrix-degrading enzymatic cascade.
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PMID:Activation of interstitial collagenase, MMP-1, by Staphylococcus aureus cells having surface-bound plasmin: a novel role of plasminogen receptors of bacteria. 1056 88


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