Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.35 (matrix metalloproteinase 9)
 2,207 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because dermatitis herpetiformis is characterized by neutrophilic inflammation and destructive changes in the basement membrane zone, we studied the in situ expression of interstitial collagenase and stromelysin-1 in 11 lesions. A prominent signal for collagenase mRNA was consistently detected in the basal keratinocytes of rete ridges surrounding the neutrophilic abscesses in 10 of 11 lesions, and the expression was independent of the age of the lesion and the migratory state of the basal keratinocytes. Expression of stromelysin-1 was detected in seven of 11 lesions and co-localized with collagenase. No expression of the 92-kDa gelatinase mRNA or matrilysin protein was found in the vicinity of neutrophilic accumulations or the damaged basement membrane. Urokinase-type plasminogen activator mRNA was found in basal keratinocytes in seven of nine samples. Collagenase, stromelysin-1, and urokinase-type plasminogen activator were not expressed in normal-appearing skin of patients with dermatitis herpetiformis. Our results suggest that in lesions of dermatitis herpetiformis, collagenase and stromelysin-1 may be induced in basal keratinocytes by neutrophil cytokines or by altered cell-matrix interactions through contact of keratinocytes with the matrix due to damaged basement membrane. Stromelysin-1, in particular, may contribute to formation of blisters by degrading basement membrane components.
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PMID:Enhanced expression of interstitial collagenase, stromelysin-1, and urokinase plasminogen activator in lesions of dermatitis herpetiformis. 763 99

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.
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PMID:Proteolytic and non-proteolytic activation of human neutrophil progelatinase B. 766 17

Many cellular properties are influenced by the surrounding environment of extracellular matrix. To better define the interaction between mononuclear phagocytes and the extracellular matrix components they contact, we studied the effect of various matrices on the biosynthesis and secretion of metalloenzymes and the tissue inhibitor of metalloproteinases in human alveolar macrophages. We found that native and denatured collagen types I and III markedly augmented production of interstitial collagenase (> 25-fold) and increased tissue inhibitor of metalloproteinases to a lesser degree (2.5-fold). In contrast, the biosynthesis of another major secreted macrophage metalloproteinase, 92-kDa gelatinase, was unaffected by contact with extracellular matrices. Furthermore, other matrix components (i.e. type IV collagen, laminin, fibronectin, elastin) failed to induce collagenase production. Maximal stimulation of macrophage collagenase production was achieved with 1-5 micrograms/ml (3-15 x 10(-9) M) denatured collagen in contact with cells for 2 h. Increased biosynthesis of collagenase was detected within 24 h of cell contact with native or denatured collagen and was accompanied by marked induction of collagenase mRNA levels. Our studies of signal transduction mechanisms demonstrated that indomethacin decreased gelatin-induced collagenase production by 90%, with enzyme levels completely restored by the addition of exogenous prostaglandin E2. Prostaglandin E2 was only effective when added within the first 2 h after indomethacin treatment. These results indicate that extracellular matrix can directly influence its remodeling and repair via regulation of the production of metalloenzymes by resident inflammatory cells. Furthermore, matrix-metalloproteinase inductive interactions are both enzyme- and matrix-specific, and are mediated, at least in part, by a prostaglandin-dependent mechanism.
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PMID:Induction of macrophage metalloproteinases by extracellular matrix. Evidence for enzyme- and substrate-specific responses involving prostaglandin-dependent mechanisms. 768 37

The present study was undertaken to determine the role of the metalloproteinase MMP-9 in the invasive phenotype of squamous-cell carcinoma of the oral cavity and the regulation of its expression. Zymographic analysis of conditioned medium from 2 highly invasive squamous-cell-carcinoma cell lines indicated large amounts of an enzyme which was indistinguishable, in size (92 kDa) from the MMP-9 pro-enzyme. Conversion of the 92-kDa gelatinase into a lower-molecular-weight species (84 kDa), identical in size to the activated gelatinase, was evident when both cell lines, which are avid secretors of urokinase, were cultured in the presence of plasminogen. Penetration of an extracellular-matrix-coated filter was dramatically reduced in the presence of the collagenase inhibitor, tissue inhibitor of metalloproteinase-2, suggesting a critical role for MMP-9 in the invasive process. Immunohistochemical studies demonstrating the presence of MMP-9 in tumor cells of resected squamous-cell cancers suggested that secretion of this collagenase by cells in vitro was reflective of the in vivo setting. Since several phorbol-ester response elements are present in the MMP-9 promoter, we determined the role of protein-kinase-C pathways in the regulation of MMP-9 expression in cultured SCC. Treatment of cells with PMA resulted in a more-than-20-fold increase in the level of protein and mRNA. Conversely, culturing of cells in the presence of the protein-kinase-C inhibitor, calphostin-C, led to a dose-dependent decrease in the amount of MMP-9 mRNA and protein, suggesting that the constitutive expression of this collagenase reflects activation of this signal transduction pathway. In summary, our data suggest that, for a sub-population of squamous-cell carcinomas, secreted MMP-9 is an important determinant of the invasive phenotype, and that the expression of this metalloproteinase is regulated by protein-kinase-C pathways.
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PMID:Role and regulation of expression of 92-kDa type-IV collagenase (MMP-9) in 2 invasive squamous-cell-carcinoma cell lines of the oral cavity. 768 50

The actions of human recombinant stromelysins-1 and -2, collagenase, gelatinases A and B and matrilysin on neonatal human proteoglycan aggregates were examined. With the exception of gelatinase B, aggrecan was degraded extensively by most metalloproteinases studied, whereas link protein showed only limited proteolysis. Sequencing studies of modified link protein components revealed that stromelysins-1 and -2, gelatinases A and B and collagenase cleaved specifically between His16 and Ile17, and matrilysin, stromelysin-2 and gelatinase A cleaved between Leu25 and Leu26. Cleavage at the former bond generated a link protein component with the same N-terminus as that isolated from newborn human cartilage. Based on previously determined in situ cleavage sites it is evident that matrix metalloproteinases are not solely responsible for the accumulation of link protein degradation products in adult human cartilage, indicating that additional proteolytic agents are involved in the normal catabolism of human cartilage matrix.
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PMID:Matrix metalloproteinases cleave at two distinct sites on human cartilage link protein. 769 69

We have compared the effects of a general matrix metalloproteinase (MMP) inhibitor (CT435) with those of a concentration-dependent specific gelatinase inhibitor (CT543; Ki < 20 nM) on bone resorption in vitro. The test systems consisted of measuring: (i) the release of 45Ca2+ from prelabelled mouse calvarial explants; (ii) the release of 45Ca2+ from prelabelled osteoid-free calvarial explants co-cultured with purified chicken osteoclasts; and (iii) lacunar resorption by isolated rat osteoclasts cultured on ivory slices. Both CT435 and CT543 dose-dependently inhibited the release of 45Ca2+ from neonatal calvarial bones stimulated by either parathyroid hormone or 1,25-dihydroxyvitamin D3. Moreover, CT543 produced a 40% inhibition at a concentration (10(-8) M) selective for the inhibition of human gelatinases A and B. CT435 (10(-5) M) and CT543 (10(-5) M) partially inhibited the release of 45Ca2+ from osteoid-free calvarial explants by chicken osteoclasts with a maximum of approximately 25% for unstimulated cultures, and approximately 36% for cultures stimulated by interleukin-1 alpha (IL-1 alpha; 10(-10) M). Neither inhibitor prevented lacunar resorption on ivory by unstimulated rat osteoclasts, but the compounds produced a partial reduction in both the number and total surface area of lacunae in IL-1 alpha-stimulated cultures, with maximal action at 10(-5) M. Neither of the inhibitors affected protein or DNA synthesis, nor the IL-1 alpha-stimulated secretion of the lysosomal enzyme beta-glucuronidase. Immunocytochemistry demonstrated that isolated rabbit osteoclasts constitutively expressed gelatinase A and synthesized gelatinase B, collagenase and stromelysin, as well as the tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) following IL-1 alpha stimulation. These experiments have shown that in addition to collagenase, gelatinases A and B are likely to play a significant role in bone resorption. They further suggest that MMPs produced by osteoclasts are released into the sub-osteoclastic resorption zone where they participate in bone collagen degradation.
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PMID:The effects of selective inhibitors of matrix metalloproteinases (MMPs) on bone resorption and the identification of MMPs and TIMP-1 in isolated osteoclasts. 769 5

Several members of the matrix metalloproteinase family have been reported to cleave aggrecan in the interglobular domain between Asn-341 and Phe-342. An antiserum was prepared against a peptide conjugate corresponding to the C-terminal sequence of the matrix metalloproteinase-generated aggrecan G1 fragment (Phe335-Val-Asp-Ile-Pro-Glu-Asn341). A quantitative radioimmunoassay, with a limit of detection of about 80 pM, was developed using this antiserum. This antiserum requires the free carboxyl group of the C-terminal asparagine for optimal recognition. If the C-terminal asparagine is excised from the sequence, replaced with closely related amino acids, or extended across the matrix metalloproteinase cleavage site, there is a 40-10,000-fold loss in detection. Using peptides cleaved from the N-terminus, it was determined that the antiserum requires the entire Phe-Val-Asp-Ile-Pro-Glu-Asn sequence for optimal recognition. The radioimmunoassay detects matrix metalloproteinase-generated G1 fragments with similar sensitivity to the Phe-Val-Asp-Ile-Pro-Glu-Asn peptide, but it does not recognize intact aggrecan. Immunoreactive aggrecan G1 fragments of molecular mass 50 kDa are generated by the matrix metalloproteinases stromelysin and gelatinase A. In contrast, under identical conditions, the closely related metalloproteinases, gelatinase B and collagenase, as well as cathepsin G, cathepsin B and human leucocyte elastase, did not generate a G1 fragment recognized by the antiserum. The anti-Phe-Val-Asp-Ile-Pro-Glu-Asn serum detects stromelysin-generated aggrecan G1 fragments from mouse, guinea pig, rabbit and human, indicating that the detection is not species-specific. This antiserum and radio-immunoassay should be useful for quantifying and characterizing matrix metalloproteinase-generated aggrecan G1 fragments in articular cartilage and synovial fluids from humans and various animal models of articular-cartilage destruction.
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PMID:Quantification of a matrix metalloproteinase-generated aggrecan G1 fragment using monospecific anti-peptide serum. 771 83

The regulatory effect of endogenously synthesized eicosanoid metabolites on the expression of tissue inhibitor of metalloproteinases (TIMP), interstitial collagenase, and 92-kDa gelatinase by human macrophages was examined. TIMP and metalloproteinase production were stimulated with three agonists that produce distinct patterns of eicosanoid synthesis: lipopolysaccharide (10 micrograms/ml), denatured collagen (10 micrograms/ml), or zymosan (1 mg/ml). Indomethacin (3 micrograms/ml) or MK886 (3 microM), a specific inhibitor of 5-lipoxygenase, was used to examine the role of endogenous metabolites of arachidonic acid. Regardless of the agonist used, TIMP production by macrophages was inhibited 65% by indomethacin, synthesis of interstitial collagenase was reduced 70%, and expression of 92-kDa gelatinase was decreased 40%. In contrast, inhibition of leukotriene synthesis had no effect on metalloproteinase or TIMP production. The agonist-stimulated increase in TIMP and collagenase production was directly correlated to the cumulative prostaglandin E2 level induced by the agonist used. However, if response to an agonist was poor, the exogenous addition of prostaglandin E2 could not increase TIMP or collagenase production more than twofold, indicating an important permissive effect of the agonist on the regulation of each protein's expression. The mechanism of indomethacin inhibition of TIMP and collagenase production was studied by labeling the cells with [35S]-methionine and performing immunoprecipitation using specific antiserum. Indomethacin markedly inhibited the lipopolysaccharide-induced biosynthesis of both TIMP and collagenase. Northern analysis revealed parallel suppression of TIMP and collagenase steady-state mRNA levels by indomethacin, indicating pretranslational control. The regulation of inflammatory-cell TIMP and interstitial collagenase expression by prostaglandin E2 suggests that therapy inhibiting the cellular response to prostaglandins may be useful in cutaneous and systemic disease states involving macrophage-mediated connective-tissue destruction.
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PMID:Agonist-induced expression of tissue inhibitor of metalloproteinases and metalloproteinases by human macrophages is regulated by endogenous prostaglandin E2 synthesis. 779 41

The peptide substrate specificities of two matrix metalloproteinases (MMPs), interstitial collagenase (MMP-1), and 92-kDa gelatinase (MMP-9), have been examined. Starting with the parent substrate, Dnp-Pro-Leu-Gly approximately Leu-Trp-Ala-D-Arg-NH2, four separate substrate mixtures were synthesized at subsites P2(Leu) through P2'(Trp). These mixtures contained either naturally occurring L-amino acids, D-amino acids, or either of two distinct sets of miscellaneous amino acids. Combined, these mixtures gave 88 unique substitutions at each position and, over the four subsites, represented 352 potential substrates. Optimal substrates were identified using a combined high performance liquid chromatography/mass spectrometry analysis as previously reported. The results gave an extended profile of the substrate specificities for both MMP-1 and MMP-9 at subsites P2(Leu) through P2'(Trp). Using the data obtained from the mapping, a new peptide substrate, Dnp-Pro-Cha-Abu approximately Smc-His-Ala-D-Arg-NH2 (where Dnp is 2,4-dinitrophenyl, Cha is cyclohexylalanine, Abu is alpha-aminobutyric acid, and Smc is S-methylcysteine) was designed and characterized. This peptide showed a 36-fold improvement in turnover (kcat/Km) versus the parent substrate by interstitial collagenase. In addition, some collagenase subsite specificities described here were found to be different from those previously reported. Experimental data show that the observed selectivity is dependent on the original peptide template employed, which has broader implications for substrate specificity studies.
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PMID:Characterization of the peptide substrate specificities of interstitial collagenase and 92-kDa gelatinase. Implications for substrate optimization. 780 5

In addition to the known 94-kd gelatinase (matrix metalloproteinase 9, MMP-9), HL-60 leukemia cells release a hither-to undescribed 45-kd metalloproteinase into the culture medium. This enzyme cleaves the synthetic substrate Pro-Gln-Gly-Ile-Ala-Gly-Gln-Arg, which represents the cleavage site for collagenases in collagen type I not between isoleucine and alanine--the typical cleavage site for collagenases--but between alanine and glycine. The enzymatic activity was purified through a combination of zinc-chelate-Sepharose column chromatography, precipitation with Fractogel TSK-AF Red and gelatin-Sepharose, and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Microsequence analysis of the NH2-terminus of the purified 45-kd proteinase revealed the sequence Asp-Ile-Ser-Lys-Tyr-Thr-Thr-Thr-, which could not be found in other proteins when searched in several protein data bases. Incubation of the enzyme immobilized on nitrocellulose membranes with polyclonal antibodies to collagenase and stromelysin or gelatinases revealed no cross-reactivity. The proteolytic activity was not increased by treatment with trypsin, 8M urea, acid, or organomercurials. The proteinase, which was inhibited by chemical inhibitors of metalloproteinases, such as phenanthrolene or EDTA, is able to degrade several matrix constituents, such as collagen type IV, fibronectin, gelatin, and proteoglycans. In contrast to all known MMPs, the proteolytic activity of the 45-kd enzyme was not abolished upon incubation with recombinant tissue inhibitors of matrix metalloproteinases (TIMP) 1 or 2. Thus, the novel enzyme may influence extracellular matrix (ECM) turnover in vivo because its activity is not influenced by specific inhibitors of MMPs.
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PMID:Leukemic cells (HL-60) produce a novel extracellular matrix-degrading proteinase that is not inhibited by tissue inhibitors of matrix metalloproteinases (TIMPs). 782 72


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