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

Periprosthetic osteolysis with or without aseptic loosening is a major clinical problem in total hip arthroplasty. While the macrophage response to prosthetic wear debris and its role in periprosthetic osteolysis has been extensively studied, information regarding other cell types (fibroblasts, osteoblasts) is limited. This study explored the response of fibroblasts to particulate wear debris. Fibroblasts isolated from interfacial membranes of patients with failed total hip replacements and normal synovial tissue, when challenged with small-sized ( < 3 microns) titanium (Ti) particles, responded with significantly enhanced expressions of collagenase, stromelysin and, to a much lesser extent, their tissue inhibitor of metalloproteinases (TIMP). These "regulated" expressions at both mRNA and protein levels were correlated with the size and composition of particles. De novo protein synthesis was required for the regulation of these mRNAs. A similar effect could be induced by the treatment of the cells with particle-free conditioned medium from Ti particle-stimulated fibroblasts. Furthermore, this conditioned medium significantly suppressed the mRNA levels of procollagen alpha 1 (I) and alpha 1 (III) in osteoblast-like MG-63 cells. It is concluded that fibroblasts stimulated with certain particle debris may play an important role in periprosthetic osteolysis by releasing bone-resorbing metalloproteinases and mediator(s) which resulted in suppressed collagen synthesis in osteoblasts.
J Bone Miner Res 1995 Sep
PMID:The potential role of fibroblasts in periprosthetic osteolysis: fibroblast response to titanium particles. 750 15

Endothelial cell-derived proteases can be classified according to their physiological role. The proteases involved in extracellular matrix degradation are important in endothelial cell migration and thereby in angiogenesis. They include the urokinase-type plasminogen activator (uPA) and the metalloproteases, collagenases, gelatinases and stromelysin. uPA secreted from endothelial cells remains associated with the cell membrane, on specific receptors localized in the vicinity of the receptors for plasminogen. This favours the local activation of plasminogen into plasmin. Plasmin, generated on the cell surface, is fully active as it is not inhibited by alpha 2-antiplasmin. Plasmin acts directly by degrading some components of the extracellular matrix and indirectly by activating the prometalloproteases. Secretion of PAI by migrating cells is generally stimulated by the same factors that induce uPA secretion, limiting the degradation of the matrix to the pericellular path. The degradation of the fibrin clot involves the tissue-type plasminogen activator tPA, which like the uPA activates plasminogen to plasmin. This system is also regulated by two different mechanisms. On the one hand, fibrin itself favours its own degradation by formation of a ternary complex, fibrin-plasminogen-tPA, in which the affinity of tPA for plasminogen is markedly increased, as compared to the affinity of unbound tPA. In addition, plasmin generated on the clot is protected from inhibition by alpha 2-antiplasmin. On the other hand, as for uPA, tPA is inhibited by PAI-1. The importance of the regulation of this system is illustrated by the thrombotic risk observed when there is either a decrease in tPA or an increase in PAI-1, and inversely by haemorrhages in the case of increase in tPA.
Baillieres Clin Haematol 1993 Sep
PMID:Endothelial cell proteases: physiological role and regulation. 751 36

In vitro angiogenesis models suggest that new blood vessel formation requires the induction and secretion by endothelial cells of matrix metalloproteinases. These enzymes assist in the controlled proteolytic degradation of the surrounding extracellular matrix during blood vessel formation. The results of in vitro studies cannot be extrapolated directly to the process of in vivo angiogenesis because the type of matrix employed and the repertoire of enzymes secreted by cells in vivo differ dramatically from in vivo conditions. To investigate the in vivo role of matrix metalloproteinases in blood vessel development, we looked for the presence of these proteinases in endothelial cells involved in fetal angiogenesis and in neovascularization of certain invasive skin tumors using immunofluorescent staining. In fetal tissue, interstitial collagenase was present in both early microvessels developing from undifferentiated mesoderm and in microvessels involved in elongation and sprout formation from preexisting blood vessels. In aggressive skin tumors, i.e., morpheaform and recurrent basal cell carcinomas and squamous cell carcinomas, there was a marked increase in the number of collagenase-containing blood vessels, often extending into the tumor nests. Immunofluorescent staining failed to detect stromelysin, matrilysin, or gelatinase A and B (72- and 92-kDa type IV collagenases, respectively) in fetal or tumor blood vessels. These findings are consistent with the hypothesis that proteolytic degradation of the extracellular matrix is required for the formation of new blood vessels. Interstitial collagenase appears to play an important role in this process.
J Invest Dermatol 1995 Sep
PMID:Matrix metalloproteinases in blood vessel development in human fetal skin and in cutaneous tumors. 754 2

We reported that specific biological activities are confined to three domains of the fibronectin (Fn) molecule [Fukai et al. (1991) J. Biol. Chem. 266, 8807; Fukai et al. (1993) Biochemistry 32, 5746]: the potent ability to stimulate the adipocyte differentiation of ST-13 cells is in the amino-terminal fibrin-binding (Fib 1) domain (referred to as Fib 1 domain activity); the RGD-dependent activities that stimulate NIH-L13 cell migration and inhibit adipocyte differentiation are in the central cell-binding (Cell) domain (Cell domain activity); and the activity that stimulates cell migration in a RGD-independent manner is in the carboxyl-terminal fibrin-binding (Fib 2) domain (Fib 2 domain activity). Human plasma Fn which was purified without exposure to a denaturant, such as urea, exhibited no Fib 1, Fib 2, or Cell domain activity. By exposure to urea or surface adsorption, Fn showed Cell domain activity but not those of the Fib 1 and Fib 2 domains. Whether the cryptic domain activities are disclosed or not depended on whether or not the responsible domains were irreversibly exposed from confined environments of Fn structure as confirmed by light-scattering measurement and enzyme immunoassay using domain-specific monoclonal antibodies. We then investigated the action of matrix metalloproteinases (MMPs) in liberating the Fib 1, Cell, and Fib 2 domain activities. Matrilysin released only the Cell domain activity. In contrast, stromelysin, collagenase, and especially gelatinase A additionally liberated the Fib 1 and Fib 2 domain activities. The Fib 1, Fib 2, and Cell domains acquired much higher activities when they were freed from linkage with adjacent domains.(ABSTRACT TRUNCATED AT 250 WORDS)
Biochemistry 1995 Sep 12
PMID:Release of biological activities from quiescent fibronectin by a conformational change and limited proteolysis by matrix metalloproteinases. 754 73

The effects of organic cosolvents on the kinetic characteristics of two matrix metalloproteinases, gelatinase A and stromelysin 1, were investigated. In each case, addition of the cosolvent resulted in a decrease in the apparent kcat/Km for the catalyzed hydrolysis of fluorogenic peptide substrates. Two factors were identified as being responsible for this decrease in catalytic activity: hydrophobic partitioning of the substrate in favor of the bulk solvent and decrease in the water content of the enzyme. The former reflects the hydrophobic nature of the enzyme-substrate interaction and the effect can be corrected for by using the solvent to water partition coefficient of the substrate in the mixed solvent systems. The catalyzed hydrolysis of substrate, corrected for the effect of hydrophobic partitioning, was demonstrated to be sixth order in water for gelatinase A and third order in water for stromelysin 1. Variation in water concentration did not produce saturation even at concentrations close to 55.5 M. The results indicate that weakly bound water molecules are essential to mediate the interaction between substrate and enzyme. The sensitivity of these enzymes to water concentration could be an important mechanism for regulating catalytic activity in vivo.
Biochemistry 1995 Sep 19
PMID:Evidence for the importance of weakly bound water for matrix metalloproteinase activity. 754 39

The activation of human neutrophil progelatinase B (pro-HNG) by a variety of proteolytic and non-proteolytic activators has been investigated. A quantitative comparison of the activation efficiencies of treatments previously reported to activate pro-HNG or the related gelatinase B species produced by other cells demonstrates that stromelysin and trypsin are good activators. HgCl2 is a moderately effective activator, while p-chloromercuribenzoate and NaOCl are poor activators. It is also shown that human matrilysin and human fibroblast-type collagenase can activate pro-HNG by a mechanism that is very similar to that of stromelysin. Initially, these proteinases hydrolyze the Glu40-Met41 bond in the propeptide domain to generate an 88 kDa inactive HNG species. Collagenase also generates a 68 kDa HNG species through hydrolysis of the Ala74-Met75 bond. Ultimately, treatment with either matrilysin, collagenase or trypsin results in the production of a 65 kDa active form of HNG that arises from hydrolysis of the Arg87-Phe88 bond. This is the same active species produced on activation by stromelysin. This cleavage site is downstream of the 'cysteine-switch' residue located at position 80 and releases it, accounting for the permanent activation of the enzyme. These results suggest that matrilysin and collagenase may be physiologically relevant activators of pro-HNG and/or other progelatinase B species. Activation by HgCl2 produces an active 68 kDa enzyme due to autolytic hydrolysis of the Ala74-Met75 bond. This species retains the cysteine switch residue; however, it is shown that it is only active in the continued presence of HgCl2. Removal of the HgCl2 restores latency, indicating that this species is reversibly activated by HgCl2, which functions by complexing the sulfhydryl group of the cysteine switch residue and keeping it dissociated from the active site zinc atom. Thus, in spite of reports to the contrary, the cysteine switch mechanism can account for the latency and activation of pro-HNG.
Biochim Biophys Acta 1995 Sep 06
PMID:Proteolytic and non-proteolytic activation of human neutrophil progelatinase B. 766 17

Soluble recombinant human fibroblast collagenase catalytic domain was highly expressed and purified from Escherichia coli. The expression construct utilized the T7 gene 10 promoter for transcription of a two-cistron messenger RNA which encoded the ubiquitin-collagenase catalytic domain fusion protein as the second cistron. The ubiquitin domain was attached to the collagenase catalytic domain with the linker sequences Gly-Gly-Thr-Gly-Asp-Val-Ala-Gln (wild type) or Gly-Gly-Thr-Gly-Asp-Val-Gly-His (mutant) which served as cleavage sites for in vitro activation. The last four residues of the linker were included based on the crystal structure of human prostromelysin-1 catalytic domain. Soluble fusion proteins purified from E. coli retained the proteolytic activity of the collagenase catalytic domain. The collagenase catalytic domain was released by either autoproteolytic or stromelysin-1-catalyzed cleavage, purified to homogeneity, and separately possess Phe-81, Val-82, or Leu-83 as the amino-terminal residue. Very similar kcat/Km values were determined for the Phe-81 and Val-82 forms using continuous fluorogenic and chromogenic peptide cleavage assays.
J Biol Chem 1995 Sep 22
PMID:Characterization of the Phe-81 and Val-82 human fibroblast collagenase catalytic domain purified from Escherichia coli. 767 41

Nevoid basal cell carcinoma syndrome (NBCCS), an autosomal dominant disorder, is characterized by the development of numerous cutaneous basal cell carcinomas (BCCs). To better characterize this disorder, we examined the expression of matrix metalloproteinase-3 (MMP-3; also known as stromelysin-1) in BCC tumor specimens, adjacent normal skin, and fibroblasts isolated from the normal-appearing skin of NBCCS patients. Three of three BCC tumors obtained from NBCCS patients overexpressed MMP-3 mRNA. In contrast, only 25% of BCC specimens in patients without NBCCS demonstrated overexpression of MMP-3 mRNA. Moreover, fibroblasts isolated and cultured from all nine uninvolved skin specimens of NBCCS patients overexpressed MMP-3 mRNA. MMP-3 mRNA was not detected or was detected at very low levels in normal skin and fibroblast cultures isolated from normal skin in nonsyndrome patients.
Mol Carcinog 1994 Sep
PMID:Increased expression of matrix metalloproteinase-3 (stromelysin-1) in cultured fibroblasts and basal cell carcinomas of nevoid basal cell carcinoma syndrome. 791 87

Stromelysin, a member of the matrix metalloproteinase family of enzymes, has been implicated in the pathogenesis of tumor metastasis and inflammatory diseases such as rheumatoid arthritis. To screen prospective inhibitors of this protease, we developed a fluorogenic substrate with excitation and emission spectra compatible with commercially available 96-well plate readers. The substrate is based on the addition of 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino] hexanoic acid (NBD) (EX467/EM534) and 7-dimethylaminocoumarin-4-acetate (DMC) (EX368/EM459) to the previously reported peptide substrate for stromelysin, Arg-Pro-Lys-Pro-Leu-Ala-Nva-Trp-NH2. The new substrate, NBD-Arg-Pro-Lys-Pro-Leu-Ala-Nva-Trp-Lys-(DMC)-NH2 is 95% quenched and the fluorescent product, Nva-Trp-Lys(DMC)-NH2 is easily detected (EX350/EM465). In competition assays the new fluorogenic substrate has a relative kcat/Km that is one half that of the parent peptide. The fluorophores NBD and DMC were chosen based on the high fluorescence yield of DMC and the overlap of the emission spectrum of DMC and excitation spectrum of NBD which results in an efficient energy transfer system in the intact substrate. These characteristics make this an excellent substrate for routine determination of in vitro activities of stromelysin inhibitors.
Ann N Y Acad Sci 1994 Sep 06
PMID:A high throughput fluorogenic substrate for stromelysin (MMP-3). 797 5

Neonatal human foreskin obtained at circumcision was cut into 2 x 2-mm pieces and placed in organ culture. Culture medium consisted of a serum-free, growth factor-free basal medium containing either 0.15 mmol/L Ca2+ or 1.4 mmol/L Ca2+. Some cultures were left as control, whereas others were treated with 3 mumol/L all-trans retinoic acid (RA). In the presence of RA, epidermal cohesion was disrupted and the upper layers separated from the viable epidermis beneath. This effect was observed under both low Ca2+ and high Ca2+ conditions. At 2-day intervals, culture fluids were collected and analyzed for serine and metalloproteinase activities. Serine proteinase activity was detected in the culture fluids and virtually all of the detected activity was dependent on the presence of plasminogen. Activity was elevated in the RA-treated tissues and this was due to increased amounts of both urokinase-type plasminogen activator (u-PA) and tissue-type plasminogen activator (t-PA). Elastase and cathepsin G were not detected in either control or RA-treated cultures. Increased plasminogen activator levels were also detected in RA-treated keratinocytes and fibroblasts in monolayer culture. Significant amounts of t-PA (though not u-PA) were found in fibroblast culture fluids, whereas both t-PA and u-PA were detected in culture fluids from keratinocytes. Metalloproteinase activity was also detected in the culture fluids of control and RA-treated tissues but in contrast to plasminogen activator, metalloproteinase activity decreased in the presence of RA. Casein and gelatin zymographic studies indicated the presence of both 92- and 72-kd gelatinases and stromelysin-1 and suggested that the decreased activity was primarily due to reduction in the 92- and 72-kd gelatinases. When serine proteinase inhibitors (aprotinin and soybean trypsin inhibitor) were included in the culture medium throughout the incubation period, epidermal discohesion was reduced. A metalloproteinase inhibitor, tissue inhibitor of metalloproteinase-2, did not have this effect. Taken together, these data show that a number of proteolytic enzymes are produced during organ culture of human skin. They suggest that these proteases may influence the structural integrity of the tissue.
Am J Pathol 1994 Sep
PMID:Expression of serine proteinases and metalloproteinases in organ-cultured human skin. Altered levels in the presence of retinoic acid and possible relationship to retinoid-induced loss of epidermal cohesion. 808 40


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