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)

A series of isothiazolones that inhibit pro-(matrix metallo-proteinase) (proMMP) activation but do not inhibit the active enzyme are effective as cartilage protectants in bovine nasal cartilage organ culture, preventing interleukin-1 (IL-1)-induced proteoglycan (aggrecan) degradation without affecting its synthesis. These compounds were found to bind to prostromelysin (proMMP-3) in a non-dialysable and stoichiometric manner. Preincubation with cartilage-protectant isothiazolones prevented the binding of [14C]iodoacetamide to Cys75 of the MMP-3 propeptide, suggesting that the activity of these compounds involves their binding to the Cys75 of the MMP zymogen. Studies following chymotrypsin activation of proMMP-3 by SDS/PAGE indicated that altered processing of the 57 kDa zymogen to the active form occurred in the presence of compound. The 53 kDa intermediate seen on normal activation was not formed; instead a different intermediate appeared with a molecular mass of approx. 46 kDa. N-terminal sequence analysis indicated that this intermediate was formed by cleavage at the putative 4-aminophenylmercuric acid cleavage site. Importantly the 45 kDa active MMP-3 species formed in the presence of compound was one amino acid residue shorter than the native MMP-3. These results suggest that the inhibition of cartilage proteoglycan degradation by isothiazolones might be due to their ability to bind to the Cys75 in the propeptide region of the MMP zymogen and interfere with its normal activation process.
Biochem J 1996 Sep 01
PMID:Isothiazolones interfere with normal matrix metalloproteinase activation and inhibit cartilage proteoglycan degradation. 880 28

Programmed cell death in mammary tissue was studied during natural weaning in lactating mice and after litter removal or milk stasis. All treatments stimulated mammary apoptosis, indicating that this process is an integral part of the tissue's involution after lactation. Induction of apoptosis was slower in natural weaning than after litter removal but occurred earlier when mice were concurrently pregnant during natural weaning. Ipsilateral induction of apoptosis by milk stasis in teat-sealed glands indicates that cell death is under local (i.e., intramammary) as well as endocrine regulation. Apoptosis detected by DNA laddering was associated with changes in expression of p53 and bax, two genes implicated in the regulation of cell death, and was accompanied by structural degeneration characteristic of mammary involution. Reciprocal changes in stromelysin mRNA, and that of its inhibitor TIMP-2, suggested that this structural reorganisation was the result of coordinated changes in gene expression favouring proteolysis of the extracellular matrix.
J Cell Physiol 1996 Sep
PMID:Programmed cell death during mammary tissue involution induced by weaning, litter removal, and milk stasis. 881 10

Matrix metalloproteinases (MMPs) are a group of enzymes with the potential to degrade extracellular matrix proteins. One of the MMPs, stromelysin-1 (MMP-3) has been localized to extracellular matrix vesicles in growth plate chondrocyte cultures, suggesting involvement of this enzyme in remodeling of the extracellular matrix during endochondral development, a process which is regulated by the vitamin D metabolites, 1,25-(OH)2D3 and 24,25-(OH)2D3. To determine whether stromelysin-1 is regulated by vitamin D as well, confluent cultures of cells derived from growth zone (GC) and resting zone (RC) rat costochondral cartilage were treated with 1 alpha, 25-(OH)2D3 (1,25) and 24R,25-(OH)2D3 (24,25), respectively, and the effect on stromelysin-1 assessed by casein gel zymography and Western blots. Although stromelysin-1 activity was enriched in the matrix vesicle fraction, only the plasma membrane enzyme was affected by the treatment; 1, 25 and 24,25 caused a marked decrease in plasma membrane stromelysin-1 activity in their target cells. Since plasma membrane protein kinase C (PKC) activity is stimulated by 1,25 and 24,25, we hypothesized that stromelysin-1 activity was regulated by the vitamin D metabolites via PKC-dependent phosphorylation. To test this, membrane fractions (containing endogenous PKC alpha and zeta as well as stromelysin-1) were incubated in the presence of purified rat brain PKC and/or recombinant human (rh) stromelysin-1 and [gamma 32 P]-ATP and anti-stromelysin-1 immunoprecipitates were analyzed by autoradiography and Western blots. Immuno-phospho-stromelysin-1 was localized to a 52-kDa band in the plasma membrane fraction only; no phosphorylation was observed in the matrix vesicle fraction. Selective inhibitors of PKC activity demonstrated that phosphorylation was inhibited by H7 and low concentrations of H8, but not by HA1004, indicating that PKC, not PKA, was responsible. Protein phosphatase 2A1 (PP2A), a serine/threonine-specific phosphatase, selectively removed the radiolabel in a time-dependent manner, providing further support for a PKC-dependent phosphorylation mechanism. Incubation of resting zone cell plasma membranes with 24,25 but not 1, 25, resulted in phosphorylation of stromelysin-1, demonstrating that the nongenomic effect was metabolite-specific. This suggests that this may be one mechanism by which vitamin D metabolites regulate stromelysin-1 activity and that PKC-dependent phosphorylation inhibits the metalloproteinase.
J Cell Physiol 1996 Sep
PMID:Vitamin D3 regulation of stromelysin-1 (MMP-3) in chondrocyte cultures is mediated by protein kinase C. 881 11

Towards gene transfer-based therapies of renal glomerulonephritis, this study examines the feasibility of using a mesangial cell vector (J. Clin. Invest. 94, 497-505, 1994) engineered to secrete interleukin-1 receptor antagonist (IL-1ra). IL-1ra cDNA was introduced into cultured rat mesangial cells, and stably transfected vector cells were established. Compared to mock transfectants, the vector cells showed blunted expression of gelatinase B, stromelysin and monocyte chemoattractant protein-1 in response to IL-1 beta. The attenuated responses were transferable to untransfected cells by cross-feeding with vector cell-conditioned media. The vector cells were then delivered into the glomeruli of rats via the renal circulation. Compared to either unmodified or mock cell-containing glomeruli, the glomeruli transferred with vector cells showed repressed expression of gelatinase B in response to IL-1 beta. Transfer of vector cells thus conferred insensitivity to IL-1 on the glomerulus. This result indicates the feasibility of modifying glomerular microenvironment against certain pathogenic mediators via the ex vivo transfer of therapeutically-relevant genes to the glomerulus.
Biochem Biophys Res Commun 1996 Sep 24
PMID:Gene transfer of interleukin-1 receptor antagonist into the renal glomerulus via a mesangial cell vector. 883 5

Fibulin-1 and fibulin-2 are two novel rod-like proteins which occur either in basement membranes or in interstitial fibrils in close association with fibronectin. They were examined for their sensitivity to proteolysis by matrix metalloproteinases (stromelysin, matrilysin), circulating proteases (thrombin, plasmin, kallikrein), leucocyte elastase and mast cell chymase. Fibulin-1 (95 kDa) was readily cleaved by leucocyte elastase, weakly by matrilysin and not by the other proteases. Cleavage occurred in a domain-connecting link region close to the N-terminus, giving rise to fragments of 70 kDa and 26 kDa. A much more extensive cleavage by all seven proteases was observed for fibulin-2 (195 kDa), giving rise to many fragments in the range 15-150 kDa. Vulnerable sites included two central link regions, the cysteine-free part of the large N-terminal globular domain but also several regions of epidermal-growth-factor(EGF)-like repeats which are a major part of the rod-like domain. The latter domain became much more sensitive to proteolysis in the presence of EDTA, demonstrating that calcium is required for stabilization. Edman degradation demonstrated cleavage of peptide bonds corresponding to the known specificities of these proteases. A similar proteolysis was also observed for fibulin-2 deposited by cultured fibroblasts into a dense fibrillar network. Since fibulin-2 is an abundant component of small and large blood vessels it could be a major target for proteolysis during vascular injuries.
Eur J Biochem 1996 Sep 01
PMID:Different susceptibilities of fibulin-1 and fibulin-2 to cleavage by matrix metalloproteinases and other tissue proteases. 884 8

Gelatinase B is a regulated matrix metalloproteinase with important role in the remodeling of extracellular matrix and many pathological conditions such as tumor invasion and rheumatoid arthritis, physiological processes including embryonic growth and development, migration of blood leukocytes into tissues and tissue remodeling. Elevated levels of certain MMPs are believed to be associated with various pathological states. We cloned the 5'-flanking 600 bp sequence of human gelatinase B gene by PCR, which controls the expression of the gene by ligating it to the chloramphenicol acetyltransferase gene. Four kinds of cell lines were used to transiently transfect. Deletion analysis revealed that 100 bp (-600 to -500 bp) contributed positively to induction by tumour necrosis factor. The 100 bp contains NF-kappa B site, Ap-1 site, PEA3 and Sp-1 site. The expression of the human gelatinase B gene varied in different cells in the presence of TNF.NF-kappa B factor may play an important role in regulating the gene expression. Comparison of the finding with those for the promoter of gelatinase A, collagenase and stromelysin shows that the determinant for the inducibility of the gelatinase B gene is more complex.
Cancer Lett 1996 Sep 10
PMID:Molecular mechanism of transcriptional activation of human gelatinase B by proximal promoter. 884 71

To assess endometrial fibroblast-cytotrophoblast interactions, we used a coculture system allowing analysis of the potential cell morphology modifications and protein secretion variations possibly involved in endometrial invasion arrest. Stromal cells and cytotrophoblasts were isolated from endometrial biopsies and first-trimester placental villi, respectively. In our culture conditions, a 57-kDa protein that was secreted by cultured fibroblasts but was absent in the 4-day coculture medium was found to be identical to prometalloproteinase-3 (proMMP-3) through determination of amino acid sequences of NH2-terminal and internal peptides. Northern blotting analysis of endometrial fibroblast total RNA showed a 38.6% metalloproteinase-3 (MMP-3) mRNA inhibition by 4-day 10(-6) M R5020 treatment. Inhibition of proMMP-3 secretion was weak when cytotrophoblasts were cultured for 4 days in a polycarbonate membrane insert over cultured fibroblasts without possible cell contact in spite of high levels of progesterone produced by cytotrophoblasts. Furthermore, cytotrophoblasts cultured on a monolayer of endometrial fibroblasts became syncytia, and most of the fibroblasts were decidualized. The closeness of the two cell types allowed paracrine relationships that might facilitate the progesterone action. Since MMP-3 is known to activate collagenases, inhibition of its secretion by cell contact might be a mechanism of invasion arrest for trophoblast cell migration.
Biol Reprod 1996 Sep
PMID:Identification of prometalloproteinase-3 as a major protein secreted by human endometrial fibroblasts and inhibited by coculture with trophoblast cells. 886 78

Restructuring of basement membranes is a hallmark of the pathology of renal cystic disorders. Here, we present findings consistent with the view that basement membrane degradation by matrix metallo-proteinases (MMPs) may contribute to abnormal basement membrane structure in polycystic kidney disease. Cells from cystic kidney tubules embedded in collagen gels appeared to migrate through the gel. This migration through collagen indicated that these cells could degrade the matrix. To examine this activity, we cultured cystic kidney tubules derived from the C57BL/6J cpk/cpk mouse, a hereditary model of polycystic kidney disease, and assayed conditioned medium for the presence of MMPs and tissue inhibitors of metalloproteinases (TIMPs). The conditioned medium from the cystic tubules contained higher than normal levels of MMP-9, MMP-2, and MMP-3 as well as TIMP-1 and TIMP-2. A 101 kDa protease was present equally in cystic and control cultures and although inhibited by EDTA, it was not inhibited by TIMPs, nor activated by the mercurial compound APMA. These data suggest that cystic kidney tubules synthesize and secrete high levels of MMPs which may then participate in the restructuring of the tubular basement membrane.
Kidney Int 1996 Sep
PMID:Matrix metalloproteinases and TIMPS in cultured C57BL/6J-cpk kidney tubules. 887 58

Glomerular mesangial cells express matrix metalloproteinase sromelysin in response to the proinflammatory cytokine IL-1 beta. The present study was conducted to identify intracellular machinery involved in this IL-1 action, especially focusing on the role of the TPA response element (TRE) located in the 5'-flanking region of the stromelysin gene. Using transient transfection with a pTRE-LacZ reporter plasmid, we detected no obvious up-regulation of TRE activity in rat mesangial cells following the IL-1 stimulation. However, the basal activity of TRE was found to be essential to the stromelysin induction, since (i) mesangial cells stably expressing a transdominant negative mutant of c-Jun, which effectively suppressed both basal and inducible TRE activity, exhibited the blunted expression of stromelysin in response to IL-1 beta, whereas (ii) transfection with a c-fos antisense gene, which suppressed only the inducible TRE activity, did not affect the stromelysin induction. To seek cooperative pathways required for the IL-1 action, we next focused on protein kinases, the potential regulators of the stromelysin gene. Stimulation of mesangial cells with a protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA), induced the stromelysin transcript without affecting TRE activity. Depletion of intracellular PKC by high-dose PMA or inhibition of PKC activity with calphostin C suppressed the stromelysin induction by IL-1 beta, suggesting the crucial contribution of a PKC-mediated, but TRE-independent pathway. In contrast, either cAMP inducer forskolin or dibutyryl cAMP suppressed the IL-1-mediated stromelysin expression. An inhibitor of cAMP-dependent protein kinase A (PKA), HA1004, enhanced the IL-1 effect in a dose-dependent manner. Unexpectedly, the inhibitory action of PKA was not through cAMP response element (CRE) but through TRE, because (i) activation of CRE was not induced by IL-1 beta, and (ii) cAMP-mediated activation of PKA suppressed the basal TRE activity. These findings elucidated the unique, binary regulation of stromelysin by IL-1 beta; that is, IL-1 up-regulated the transcript via the PKC-dependent pathway under the cooperation with constitutively active TRE, and this stimulatory effect was in part counterbalanced by the IL-1-inducible PKA which down-regulated the basal TRE activity.
Kidney Int 1996 Sep
PMID:Opposite, binary regulatory pathways involved in IL-1-mediated stromelysin gene expression in rat mesangial cells. 887 64

Recent investigations imply that a key mechanism in the pathogenesis of periodontal disease may be the ability of oral microorganisms to induce production and/or activation of matrix metalloproteinases (MMPs) in the host tissues. It has been suggested that the pharmacologic inhibition of MMP activity could play an important role in achieving a desirable outcome in periodontal therapy. The efficacy of locally delivered antibiotics on the level of gingival crevicular fluid (GCF) stromelysin (SL) and tissue inhibitor of metalloproteinases (TIMP) on sites with a history of a poor response to mechanical treatment was studied. Fifty-two patients with 4 periodontal pockets > or = 5 mm and bleeding on probing were randomized into four groups of 13 patients. One group received scaling and root planing alone and the other three groups received scaling and root planing plus a locally delivered antimicrobial system. These included 25% tetracycline fiber, 2% minocycline gel, and 25% metronidazole gel. The GCF samples taken at baseline and 6 weeks after treatments were analyzed using an enzyme linked immunosorbent assay (ELISA). GCF SL levels significantly decreased after adjunctive tetracycline fiber (paired t-test, P = 0.020) and minocycline gel (paired t-test, P = 0.023) treatments whereas it remained almost unchanged in the other two groups. While the GCF TIMP level did not change significantly in the scaling and root planing alone group, it significantly increased for all three adjunctive antimicrobial treatments (for tetracycline fiber P < 0.001, minocycline gel P = 0.005, metronidazole gel P < 0.001). The use of adjunctive locally delivered antimicrobial systems, particularly the tetracycline family, may offer an advantage in changing the metalloproteinase profile of the GCF to one more compatible with periodontal health.
J Periodontol 1996 Sep
PMID:The effect of subgingival antimicrobial therapy on the levels of stromelysin and tissue inhibitor of metalloproteinases in gingival crevicular fluid. 888 43


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