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)

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

Epithelial cell lines (BC1, BC3, BC4, and BC5), derived from 4 separate invasive and metastatic rat mammary carcinomas, all secreted interstitial collagenase (matrix metalloproteinase 1, MMP 1) in culture. Neither a cloned cell line (A5P/B10), derived from a noninvasive rat epithelial tumor, nor nonneoplastic rat fibroblasts secreted the enzyme. Western blot analyses of proteins extracted from the plasma membranes indicated the presence of interstitial collagenase (MMP 1) on the surface of all of the 6 cell lines. These data suggest that the control of collagenolysis may involve the association of collagenase molecules with the plasma membrane. The aggressiveness of malignant tumors may be due in part to the breakdown of such a control.
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PMID:Interstitial collagenase (matrix metalloproteinase 1) associated with the plasma membrane of both neoplastic and nonneoplastic cells. 165 15

Collagenolytic activity, extracted from 55 tumor and healthy corresponding intestinal control samples, was determined by 3 different assays using soluble type I and fibrillar type I and III collagen, respectively, as substrate. The enzyme extracted from tumor-digested collagen type I reconstituted fibrils and yielded the three-quarter segments characteristic for the action of one of the matrix metalloproteinases: MMP-I or mammalian collagenase. Metal-chelating agents such as EDTA and O-phenanthrolin indeed inhibited this activity. Collagenolytic activities were calculated on the basis of wet weight, total DNA and total extracted protein. Correlations were sought between levels of activity and both clinicopathological stage (Dukes' staging) and grade of histological differentiation. In all the assays applied, significant correlations were found between grade of histological differentiation and collagenolytic activity expressed as the tumor/control ratios: poorly differentiated tumors exhibited a higher tumor/control ratio than well-differentiated tumors. Also, tumors penetrating into the serosa showed a higher tumor/control ratio than tumors invading the muscularis propria only. A relation between collagenolytic activity and clinico-pathological stage was observed only if activities were calculated on a DNA basis. These results confirm a relationship between the histological appearance of a tumor and its enzymatic potential to degrade interstitial collagens.
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PMID:Correlation between collagenolytic activity and grade of histological differentiation in colorectal tumors. 216 97

Analysis of collagenolytic activity in gingival crevicular fluid (GCF) has revealed the presence of an enzyme capable of fragmenting native 3/4- and 1/4-collagen cleavage products generated by collagenase. An enzyme with similar activity was also identified in media conditioned by fibroblasts from rat periodontal ligament and gingiva, and by rat osteoblastic cells (ROS 17/2.8, 17/2A, 17/2B). In culture, the enzyme was secreted in a latent form that could be activated by organomercurials. For further characterization of this novel enzyme (MMP-V), the osteoblast proteinase was partially purified. ROS 17/2.8 conditioned medium was harvested daily and the 25%-60% sat. ammonium sulfate fraction chromatographed on an AcA 54 gel filtration column. Latent forms of MMP-V (apparent Mr approximately 54 k) and collagenase (Mr approximately 54 k) were resolved from gelatinase (Mr approximately 76 k) and two collagenase inhibitors (Mr approximately 62 k, approximately 36 k). Activated MMP-V degraded native 3/4-collagen fragments from collagen types I and II in a step-wise manner and was active on denatured collagen. MMP-V showed a divalent cation requirement, was active at neutral pH, and was inhibited by collagenase inhibitor and fetal bovine serum, but not by serine, thiol, or carboxyl proteinase inhibitors. These properties indicate that MMP-V is a member of the matrix-degrading, neutral-metalloproteinase family of enzymes which include collagenase, gelatinase, stromelysin, and telopeptidase. The enzyme may function in the degradation of collagen fibrils by cleaving proteinase-resistant 3/4-collagen fragments that are stabilized by association with neighboring collagen molecules.
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PMID:Initial characterization of a neutral metalloproteinase, active on native 3/4-collagen fragments, synthesized by ROS 17/2.8 osteoblastic cells, periodontal fibroblasts, and identified in gingival crevicular fluid. 304 Aug 31

Rabbit synovial fibroblasts (RSF) express basal levels of the metalloproteinases (MMP) collagenase, stromelysin-1 and 92-kD gelatinase when plated on intact fibronectin (FN), but elevated levels when plated on either the central RGD-containing cell-binding region of FN (120FN) or antibody against the alpha 5 beta 1 integrin, suggesting that domains outside 120FN may suppress the induction of MMP (Werb, Z., P. M. Tremble, O. Behrendtsen, E. Crowley, and C.H. Damsky. 1989. J. Cell Biol. 109:877-889). We therefore attempted to reconstitute the basal signaling of intact FN by plating RSF on 120FN together with domains of FN outside this region. Large COOH-terminal fragments containing both the heparin-binding and HICS domains suppressed MMP when combined with 120FN. To map the active sequences, peptides from this region and larger fragments that did, or did not, include the CS-1 portion of IIICS were tested. Only CS-1 peptide, or larger fragments containing CS-1, suppressed MMP expression induced by 120FN. In contrast, peptide V from the heparin-binding region, shown previously to stimulate focal contact formation, further enhanced MMP expression by RSF when present on the substrate with 120FN. RSF expressed alpha 4 beta 1 integrin, the receptor for CS-1, and the anti-alpha 4 mAb blocked the ability of CS-1 to suppress MMP induction by 120FN. These results show that signals modulating MMP expression and focal contact assembly are regulated independently, and that cooperative signaling by alpha 5 beta 1 and alpha 4 beta 1 integrins plays a dominant role in regulating expression of these extracellular matrix-remodeling genes in response to FN. This work demonstrates directly the modular way in which information in the extracellular matrix is detected and processed by cell surface receptors.
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PMID:Cooperative signaling by alpha 5 beta 1 and alpha 4 beta 1 integrins regulates metalloproteinase gene expression in fibroblasts adhering to fibronectin. 753 77

1. The kinetics of the degradation of the kinins bradykinin and Met-Lys-bradykinin, angiotensins I and II and the tachykinin substance P by PMNL-collagenase (MMP 8), PMNL-gelatinase (MMP 9) and by the recombinant catalytic domain of MMP 8 (rcd-PMNL-c) was examined by RP-HPLC. The resulting fragments were identified by automated Edman degradation or by amino acid analysis. 2. The initial degradation rates of substance P at a substrate concentration of 25 microM were 5 min-1 for MMP 9 and 150 min-1 for MMP 8. The kinetic constants KM and kcat were determined by concentration-dependent measurements. For MMP 8/substance P the constants were KM = 78 +/- 14 microM and kcat = 412 +/- 67 min-1. For MMP 9/substance P the constants were KM = 91 +/- 15 microM and kcat = 25 +/- 4 min-1. Both enzymes cleaved substance P between Gln6 and Phe7 and between Gly9 and Leu10. 3. Under the same conditions, MMP 8 degraded angiotensin I at an initial rate of 20 h-1, resulting mainly in the vasoactive fragments angiotensin II and angiotensin(1-7). At a substrate concentration of 25 microM and an enzyme/substrate ratio of 1:100, angiotensin II was degraded very slowly (19% in 24 h) by MMP 8. Under these conditions, MMP 9 degraded angiotensin I to a lesser extent than MMP 8 (25% in 24 h) and was unable to cleave angiotensin II. 4. Under the same conditions, bradykinin and Met-Lys-bradykinin were cleaved by PMNL-collagenase at a rate of 20% in 24 h, producing BK(1-7) and BK(1-8). PMNL-gelatinase was unable to cleave the kinins under these conditions. 5. In all cases, rcd-PMNL-c produced the same fragments as wild type PMNL-collagenase, but at a significantly lower rate.
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PMID:Degradation of kinins, angiotensins and substance P by polymorphonuclear matrix metalloproteinases MMP 8 and MMP 9. 753 73

In arterial hypertension or congestive heart failure, myocardial fibrosis is associated with an activated renin-angiotensin-aldosterone system (RAAS). This reactive fibrosis presents as an excessive accumulation of fibrillar collagen within the normal connective tissue structures of the myocardium in either ventricle, irrespective of its haemodynamic load. It therefore would appear that circulating (hormonal) and not haemodynamic factors are responsible for this adverse fibrous tissue response. The cardiac fibroblast expresses mRNA for types I and III collagens, the major fibrillar collagens in the heart, and for collagenase or matrix metalloproteinase 1 (MMP 1), the key enzyme for interstitial collagen degradation. Therefore, adult rat cardiac fibroblasts were cultured to ascertain whether the RAAS effector hormones angiotensin II (Ang II) or aldosterone (Aldo) directly stimulate collagen synthesis or inhibit MMP 1 production. Collagen synthesis, determined by 3H-proline incorporation and MMP 1 activity determined by degradation of 14C-collagen, were measured under serum-free conditions in confluent, quiescent fibroblasts after 24 h incubation with Ang II or Aldo over a wide range of concentrations (10(-11) -10(-6) M). In addition, collagen synthesis was measured after incubation with the mineralocorticoid, dexoycorticosterone (DOC), or the prostaglandin, PGE2. Collagen synthesis, normalized per total protein synthesis, increased significantly in a dose-dependent manner after incubation with either mineralocorticoid hormone, Aldo or DOC, or after incubation with Ang II compared with untreated control cells. In contrast, collagen synthesis was significantly decreased with PGE2 treatment. This increase in collagen synthesis in Ang II or mineralocorticoid-stimulated fibroblasts could be completely abolished by Ang II type 1 or mineralocorticoid receptor antagonists, respectively. (ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hormonal regulation of cardiac fibroblast function. 755 72

Membrane-type matrix metalloproteinase (MT-MMP), which we have identified recently, is unique in its transmembrane (TM) domain at the C terminus and mediates activation of pro-gelatinase A on the cell surface (Sato, H., Takino, T., Okada, Y., Cao, J., Shinagawa, A., Yamamoto, E., and Seiki, M. (1994) Nature 370, 61-65; Takino, T., Sato, H., Yamamoto, E., and Seiki, M. (1995) Gene (Amst.) 115, 293-298). In addition to MT-MMP, a novel MMP-related cDNA of 2.1 kilobases was isolated from a human placenta cDNA library. The cDNA contains an open reading frame for a new MMP. The deduced protein composed of 604 amino acids was closely related to MT-MMP in the amino acid sequence (66% homology at the catalytic domains) and has a potential TM domain at the C terminus. Monoclonal antibodies raised against the synthetic peptide recognized a 64-kDa protein as the major product in the transfected cells. TIMP-1 fused with the potential TM domain was localized on the cell surface while native TIMP-1 is in the culture medium. Thus, we called the second membrane-type MMP, MT-MMP-2 and renamed MT-MMP, MT-MMP-1. MT-MMP-1 and -2 are thought to form a distinct membrane-type subclass in the MMP family since all the others are secreted as soluble forms. Like MT-MMP-1, expression of MT-MMP-2 induced processing of pro-gelatinase A (68-kDa in gelatin zymography) into the activated form of 62-kDa fragments through a 64-kDa intermediate form. Expression of MT-MMP-2 mRNA was at the highest levels in the brain where MT-MMP-1 was at the lowest level compared to other tissues. MT-MMP-1 and -2 are thought to be utilized for extracellular matrix turnover on the surface of cells under different genetic controls.
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PMID:Identification of the second membrane-type matrix metalloproteinase (MT-MMP-2) gene from a human placenta cDNA library. MT-MMPs form a unique membrane-type subclass in the MMP family. 755 40

The precursor of matrix metalloproteinase 9 (pro-MMP-9, progelatinase B) noncovalently binds to tissue inhibitor of metalloproteinases (TIMP)-1 through the C-terminal domain of each molecule. We have isolated the proMMP-9.TIMP-1 complex from the medium of human fibrosarcoma HT-1080 cells and investigated the activation processes of the complex by 4-aminophenylmercuric acetate, trypsin, and matrix metalloproteinase 3 (MMP-3, stromelysin 1). The treatment of the proMMP-9.TIMP-1 complex with 4-aminophenylmercuric acetate or trypsin converts proMMP-9 to lower molecular weight species corresponding to active forms, but no gelatinolytic activity is detected. The lack of enzymic activity results from binding of TIMP-1 to the activated MMP-9. The treatment of the proMMP-9.TIMP-1 complex with a possible physiological proMMP-9 activator, MMP-3, does not reveal any gelatinolytic activity unless the molar ratio of MMP-3 to the complex exceeds 1. This is due to the inhibition of MMP-3 by TIMP-1 forming a ternary proMMP-9.TIMP-1.MMP-3 complex. The formation of the ternary complex weakens the interaction between proMMP-9 and TIMP-1, resulting in partial dissociation of the complex into proMMP-9 and the TIMP-1.MMP-3 complex. When MMP-3 is in excess, the propeptide is completely processed, and the full activity of MMP-9 is detected. Similarly, the proMMP-9.TIMP-1 complex inhibits MMP-1 (interstitial collagenase) and in turn renders the proMMP-9 activable by a catalytic amount of MMP-3. These results suggest that formation of the proMMP-9.TIMP-1 complex regulates extracellular matrix breakdown in tissue by switching the predominant MMP activity from one type to another.
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PMID:Steps involved in activation of the pro-matrix metalloproteinase 9 (progelatinase B)-tissue inhibitor of metalloproteinases-1 complex by 4-aminophenylmercuric acetate and proteinases. 762 79

We determined the expression pattern of the matrix metalloproteinase interstitial collagenase (MMP-1) during mouse embryo development using in situ hybridization and immunohistochemistry. Localized MMP-1 mRNA was first detected at 14.5 days postconceptus. The spatial and temporal expression was restricted to areas of endochondral and intramembranous bone formation, such as in the mandibula, maxilla, clavicle, scapula, in the vertebrae, and in the dorsal, but not the ventral part of the ribs. The highest levels of MMP-1 transcripts and MMP-1 protein were found in the metaphyses and diaphyses of the long bones. MMP-1 was expressed by hypertrophic chondrocytes and by osteoblastic cells localized along the newly formed bone trabeculae. No expression was detected in osteoclasts. Two other related members of the MMP family, stromelysin-1 (MMP-3) and stromelysin-2 (MMP-10), were not expressed during days 7.5 and 16.5 of mouse embryogenesis. The tissue-specific expression of MMP-1 and the exclusive ability of interstitial collagenase to digest native collagen of types I, II, III, and X, the major components of bone, cartilage, and tendon, strongly suggests an important and specific function of this enzyme in bone development and remodeling.
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PMID:Expression of interstitial collagenase during skeletal development of the mouse is restricted to osteoblast-like cells and hypertrophic chondrocytes. 766 31


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