Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.23 (MMP)
 4,246 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies have shown that matrix vesicles isolated from cultures of costochondral growth zone chondrocytes and treated with 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] can activate recombinant human latent transforming growth factor beta1 (rhTGF-beta1). It is unknown what enzyme or other factor in the extracellular organelles is responsible for the activation. This study tested the hypothesis that enzymes present in matrix vesicles can activate latent TGF-beta1 and that this is regulated by 1alpha,25(OH)2D3. To do this, we examined the ability of matrix vesicle extracts to activate small latent rhTGF-beta1. In addition, enzymes previously determined to be present in matrix vesicles were screened for their ability to activate small latent rhTGF-beta1. Recombinant human matrix metalloproteinase 2 (rhMMP-2; 72 kDa gelatinase), rhMMP-3 (stromelysin 1), purified human plasminogen, and purified urokinase (plasminogen activator) were each tested at varying concentrations. To assess the role of cell maturation, we used a cell culture model in which chondrocytes are derived from two distinct zones of rat costochondral cartilage, the resting zone and the growth zone. Matrix vesicles were isolated from these cultures and then tested. The results showed that extracts of matrix vesicles produced by both growth zone and resting zone chondrocytes were able to activate small latent rhTGF-beta1. The effects were dose and time dependent, with greater activity being found in extracts of matrix vesicles from the growth zone chondrocyte cultures. Only rhMMP-3 was able to activate small latent rhTGF-beta1, indicating that stromelysin-1, but not MMP-2, plasminogen, or urokinase, was involved. As observed in the extracts, the effect of rhMMP-3 was time and dose dependent. When anti-MMP-3 antibody was added to matrix vesicle extracts from both cell types, activation of small latent rhTGF-beta1 was dose-dependently blocked. Neither 1alpha,25(OH)2D3 nor 24R,25(OH)2D3 had a direct effect on activation of small latent rhTGF-beta1 by the extracts. However, when intact matrix vesicles were treated with 1alpha,25(OH)2D3, their ability to activate small latent rhTGF-beta1 was increased. Inhibition of phospholipase A2 with quinacrine blocked the 1alpha,25(OH)2D3-dependent effect. These results suggest that the ability of 1alpha,25(OH)2D3-treated matrix vesicles to activate small latent TGF-beta1 is via action of the secosteroid on the matrix vesicle membrane, not on the enzymes responsible for activating latent TGF-beta1. Because matrix vesicles isolated from growth zone chondrocytes have been shown to contain increased phospholipase A2 activity after treatment with 1alpha,25(OH)2D3, it is likely that this secosteroid promotes loss of membrane integrity through phospholipase A2-dependent formation of lysophospholipids, resulting in the release of MMP-3 into the matrix, where latent TGF-beta1 is stored. Taken together, the results of the current study show that matrix vesicles produced by growth plate chondrocytes contain MMP-3, that this enzyme is at least partially responsible for activation of small latent TGF-beta1 in the matrix, and that 1alpha,25(OH)2D3 regulates MMP release from matrix vesicles.
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PMID:Activation of latent transforming growth factor beta1 by stromelysin 1 in extracts of growth plate chondrocyte-derived matrix vesicles. 1145 Jul 4

Women are more susceptible to anterior cruciate ligament (ACL) injuries than men performing similar athletic activities. Because tissue remodeling may affect ligament strength, we assessed expression of tissue remodeling effector genes in the human ACL. Specifically, we surveyed ACL for RNAs encoding all known matrix metalloproteases (MMPs) and tissue inhibitors of metalloproteases (TIMPs) by reverse transcription/polymerase chain reaction (RT-PCR). These experiments revealed that mRNAs encoding nine of sixteen MMPs and all four TIMPs are present in the normal ACL. The nine expressed proteases were MMPs 1-3, 7, 9, 11, 14, and 17 (collagenase 1, gelatinase A, stromelysin 1, matrilysin, gelatinase B, stromelysin 3, and membrane types 1 and 4, respectively), and MMP-18. Genes for MMPs 8, 10, 12, 13, 15, and 16 appeared not to be expressed in ACL, as their mRNAs were not detected using RT-PCR conditions that did yield positive signals from other tissues (testis or bone). We conclude that numerous genes encoding tissue remodeling effector proteins are expressedin the human ACL.
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PMID:Expression of matrix metalloprotease and tissue inhibitor of metalloprotease genes in human anterior cruciate ligament. 1151 74

Cells of the monocyte/macrophage lineage are involved in the development of inflammatory joint diseases such as rheumatoid arthritis. This disease is characterized by cartilage degradation and synovial membrane inflammation with a progressive loss of joint function. The pathological processes are still not well understood. Therefore it would be interesting to develop a suitable experimental in vitro model system for defined studies of monocyte/macrophage and chondrocyte interactions at the molecular level. For that purpose we cocultured chondrocytes from adult human articular cartilage with human monocytes and macrophages for defined periods of time in agarose without addition of serum. We performed zymographic and western blot analysis of culture medium, completed by quantitative RT-PCR of each chondrocyte, monocyte and macrophage RNA, respectively. The reliability of the newly established coculture systems is confirmed by causing a clear decrease of intact aggrecan in the coculture medium plus concurrent appearance of additional smaller fragments and a reduction of chondrocyte aggrecan and collagen II gene expression in the presence of monocytes. In culture medium from cocultures we detected active forms of the matrix metalloproteinases MMP-1, MMP-3 and MMP-9 accompanied by induction of gene expression of MMP-1, membrane type 1 MMP (MT1-MMP) and tissue inhibitor of metalloproteinase 2 (TIMP-2) in chondrocytes. No gene expression of MMP-9 was detectable in chondrocytes, the enzyme was solely expressed in monocytes and macrophages and was downregulated in the presence of chondrocytes. Our results suggest that MMP-9 protein in coculture medium originated from monocytes and macrophages but activation required chondrocyte-derived factors. Because addition of plasmin, a partial activator of pro-MMP-3 and pro-MMP-1, enhanced the activation of pro-MMP-9 and pro-MMP-1 in cocultures but not in monocultured macrophages, and the presence of MMP-3 inhibitor II prevented pro-MMP-9 activation, we assumed a stepwise activation process of pro-MMP-9 that is dependent on the presence of at least MMP-3 and possibly also MMP-1.
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PMID:Paracrine interactions of chondrocytes and macrophages in cartilage degradation: articular chondrocytes provide factors that activate macrophage-derived pro-gelatinase B (pro-MMP-9). 1171 48

Gelatinases have been shown to play a key role in angiogenesis and tumor metastasis. Small molecular weight synthetic inhibitors for these enzymes are highly sought for potential use as anti-metastatic agents. Virtually all of the known inhibitors of matrix metalloproteinases (MMPs) are broad spectrum. We report herein the synthesis and kinetic characterization of two compounds, 4-(4-phenoxyphenylsulfonyl)butane-1,2-dithiol (compound 1) and 5-(4-phenoxyphenylsulfonyl)pentane-1,2-dithiol (compound 2), that are potent and selective gelatinase inhibitors. These compounds are slow, tight-binding inhibitors of gelatinases (MMP-2 and MMP-9) with K(i) values in the nanomolar range. In contrast, competitive inhibition of the catalytic domain of membrane-type 1 metalloproteinase (MMP-14(cat)) with comparable K(i) values (K(i) approximately 200 nm) was observed. Binding to stromelysin (MMP-3) was substantially weaker, with K(i) values in the micromolar range (K(i) approximately 10 microm). No binding to matrilysin (MMP-7) and collagenase 1 (MMP-1) was detected at inhibitor concentrations up to 60 microm. We have previously shown that synthetic MMP inhibitors work synergistically with TIMP-2 in the promotion of pro-MMP-2 activation by MT1-MMP in a process that depends on the affinity of the inhibitor toward MT1-MMP. It is shown herein that the dithiols are significantly less efficient (>100-fold) than marimastat, a broad-spectrum MMP inhibitor, in enhancing pro-MMP-2 activation in cells infected to express MT1-MMP, consistent with the lower affinity of the dithiols toward MT1-MMP. Thus, in contrast to broad-spectrum MMP inhibitors, the dithiols are less likely to promote MT1-MMP-dependent pro-MMP-2 activation in the presence of TIMP-2, while maintaining their ability to inhibit active MMP-2 effectively.
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PMID:Design, synthesis, and characterization of potent, slow-binding inhibitors that are selective for gelatinases. 1179 Jul 86

Medicinal plants contain pharmacological substances including flavonoids, and their extracts have been therapeutically administered for cancer therapy in vitro and in vivo. We investigated the efficacy of a polymethoxy flavonoid, nobiletin, from Citrus depressa on tumor invasion in vitro. Nobiletin inhibited the tumor-invasive activity of human fibrosarcoma HT-1080 cells in the Matrigel model, whereas a similar inhibition was observed upon exogenously adding tissue inhibitors of metalloproteinases (TIMPs)-1 and -2. The gene expression and production of pro-matrix metalloproteinase 9 (proMMP-9)/progelatinase B and proMMP-1/interstitial procollagenase were specifically suppressed by nobiletin in 12-O-tetradecanoylphorbol 13-acetate-stimulated HT-1080 cells. In contrast, the gene expression and production of TIMP-1, but not TIMP-2, were enhanced by nobiletin. We also demonstrated that nobiletin suppressed the 12-O-tetradecanoylphorbol 13-acetate-induced binding activity of activator protein-1. Furthermore, a phosphatidylinositol 3-kinase inhibitor, LY-294002, was found to mimic the different actions of nobiletin on the production of proMMP-9 and TIMP-1. These results suggest that nobiletin inhibits tumor cell invasive activity not only by suppressing the expression of MMPs but also augmenting TIMP-1 production in tumor cells, and that the nobiletin-mediated inhibition of activator protein-1 binding activity is at least partly involved in the suppression of MMP expression. Furthermore, we suggest a possible mechanism by which nobiletin may interfere in the phosphatidylinositol 3-kinase pathway, which divergently regulates the production of MMP and TIMP-1.
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PMID:Inhibition of activator protein-1 binding activity and phosphatidylinositol 3-kinase pathway by nobiletin, a polymethoxy flavonoid, results in augmentation of tissue inhibitor of metalloproteinases-1 production and suppression of production of matrix metalloproteinases-1 and -9 in human fibrosarcoma HT-1080 cells. 1186 77

Luteal tissue contains matrix metalloproteinases (MMPs) that cleave specific components of the extracellular matrix (ECM) and are inhibited by tissue inhibitors of metalloproteinases (TIMPs). We previously reported a decrease in luteal TIMP-1 within 15 min of prostaglandin F(2 alpha) (PGF(2 alpha))-induced luteolysis. An increase in the MMP:TIMP ratio may promote ECM degradation and apoptosis, as observed in other tissues that undergo involution. The objectives of these experiments were to determine whether 1) PGF(2 alpha) affects expression of mRNA encoding fibrillar collagenases (MMP-1 and -13), gelatinases A and B (MMP-2 and -9), membrane type (mt)-1 MMP (MMP-14), stromelysin (MMP-3), and matrilysin (MMP-7), and 2) PGF(2 alpha) increases MMP activity during PGF(2 alpha)-induced luteolysis in sheep. Corpora lutea (n = 3-10/time point) were collected at 0, 15, and 30 min and 1, 2, 4, 6, 12, 24, and 48 h after PGF(2 alpha) administration. Northern blot analysis confirmed the presence of all MMPs except MMP-9. Expression of mRNA for the above MMPs (except MMP-2) increased significantly (P < 0.05) by 30 min, and all MMPs increased significantly (P < 0.05) by 6 h after PGF(2 alpha) administration. Expression of MMP-14 mRNA increased significantly (P < 0.05) by 15 min post-PGF(2 alpha) and remained elevated through 48 h. MMP activity in luteal homogenates (following proenzyme activation and inactivation of inhibitors) was increased significantly (P < 0.05) by 15 min and remained elevated through 48 h post-PGF(2 alpha). MMP activity was localized (in situ zymography) to the pericellular area of various cell types in the 0-h group and was markedly increased by 30 min post-PGF(2 alpha). MMP mRNA expression and activity were significantly increased following PGF(2 alpha) treatment. Increased MMP activity may promote ECM degradation during luteolysis.
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PMID:Matrix metalloproteinase expression and activity following prostaglandin F(2 alpha)-induced luteolysis. 1187 75

The amount of elastic fibers from lesional and healthy skin areas of five patients with anetoderma was determined by automated image analysis. Dermal elastic fibers were almost completely absent in anetodermic skin and preelastic fibers were undetectable or extremely rare. Organ cultures were performed using explants from affected and unaffected skin areas of the same patient. We identified and quantified proteases in the culture media of explants: MMP-1 (collagenase 1), MMP-2 and MMP-9 (gelatinases A and B), MMP-3 (stromelysin 1), MMP-7 (matrilysin 1), and tissue inhibitors of metalloproteinases, TIMP-1 and TIMP-2. The data were compared with those of two healthy donors. For the five samples of anetodermic skin, MMP-1 levels were significantly higher compared with the uninvolved cultures and the two healthy samples. A significant increase of TIMP-1 expression was also observed in the affected cultures. We demonstrated a significant increase in the production of gelatinase A in lesional skin when compared with nonlesional skin and healthy donor samples. We found no significant production of TIMP-2 in the five samples of anetodermic skin compared with the samples from the two healthy donors. There was a significant decrease in TIMP-2 expression in the five nonlesional samples compared with the control samples. These data are in favor of an altered balance in anetodermic patients between MMP-2 and TIMP-2. Levels of MMP-9, MMP-3, and MMP-7 were significantly higher in the culture-conditioned media of the anetodermic skin samples than the nonlesional skin cultures. Because MMP-3, MMP-7, MMP-9 are known to degrade elastin, and MMP-3 can activate the latent forms of MMP-7 and MMP-9, we propose that these metalloproteinases also participate in the degradation of elastic fibers in anetodermic skin.
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PMID:Anetoderma: an altered balance between metalloproteinases and tissue inhibitors of metalloproteinases. 1197 71

Bisphosphonates (clodronate, alendronate, pamidronate and zoledronate) at therapeutically attainable non-cytotoxic concentrations inhibited MMP-3, -12, -13 and -20 as well as MMP-1, -2, -8 and -9, but not urokinase-type plasminogen activator (uPA), a serine proteinase and a pro-MMP activator. Dose-dependent inhibition was shown by three independent MMP assays. The inhibition was reduced in the presence of an increased concentration of Ca(2+) when compared to physiologic Ca(2+) concentration. Alendronate inhibited the in vitro invasion (Matrigel) of human HT1080 fibrosarcoma and C8161 melanoma cells, and the random migration of these malignant and endothelial cell lines capable of expressing MMPs and uPA. The concentration of alendronate required to inhibit 50% of the activity (IC(50)=40-70 microM) of MMPs corresponded to the IC(50) of down-regulation of in vitro invasion and migration. The ability of bisphosphonates to down-regulate the in vitro invasion and random migration was comparable or slightly better in relation to the selective gelatinase inhibitor CTTHWGFTLC peptide. Alendronate but not CTTHWGFTLC peptide promoted the adhesion of HT1080 fibrosarcoma and C8161 melanoma cell lines on fibronectin. Bisphosphonates are broad-spectrum MMP inhibitors and this inhibition involves cation chelation. Bisphosphonates further exert antimetastatic, anti-invasive and cell adhesion-promoting properties, which may prevent metastases not only into hard tissues but also to soft tissues.
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PMID:Bisphosphonates inhibit stromelysin-1 (MMP-3), matrix metalloelastase (MMP-12), collagenase-3 (MMP-13) and enamelysin (MMP-20), but not urokinase-type plasminogen activator, and diminish invasion and migration of human malignant and endothelial cell lines. 1198 68

Oral squamous cell carcinoma (SCC) is characterized by invasive growth and the propensity for distant metastasis. The expression of specific adhesion receptors promotes defined interactions with the specific components found within the extracellular matrix (ECM). We previously showed that the alpha v beta 6 fibronectin receptor is highly expressed in oral SCC. Here we forced expression of the beta 6 subunit into poorly invasive SCC9 cells to establish the SCC9 beta 6 cell line and compared these two cell lines in several independent assays. Whereas adhesion to fibronectin was unaffected by the expression of beta 6, migration on fibronectin and invasion through a reconstituted basement membrane (RBM) were both increased. Function-blocking antibodies to alpha v beta 6 (10D5) reduced both migration on fibronectin and invasion through an RBM, whereas anti-alpha 5 antibodies were effective only in suppressing migration on fibronectin, not invasion. Expression of beta 6 also promoted tumor growth and invasion in vivo and modulated fibronectin matrix deposition. When grown as a co-culture with SCC9 cells, peritumor fibroblasts (PTF) organized a dense fibronectin matrix. However, fibronectin matrix assembly was decreased in co-cultures of SCC9 beta 6 cells and PTF and this decrease was reversed by the addition of function-blocking anti-alpha v beta 6 antibodies. The expression of beta 6 also resulted in increased levels of matrix metalloproteinase 3. Addition of the general MMP inhibitor GM6001 to SCC9 beta 6/PTF co-cultures dramatically increased fibronectin matrix assembly in a similar fashion as incubation with anti-alpha v beta 6 antibodies. These results demonstrate that expression of beta 6 (1) increases oral SCC cell motility and growth in vitro and in vivo; (2) negatively affects fibronectin matrix assembly; and (3) stimulates the expression and activation of MMP3. We suggest that the integrin alpha v beta 6 is a key component of oral SCC invasion and metastasis through modulation of MMP-3 activity.
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PMID:Expression of integrin beta 6 enhances invasive behavior in oral squamous cell carcinoma. 1200 35

Morphological changes observed in OA include cartilage erosion as well as a variable degree of synovial inflammation. Current research attributes these changes to a complex network of biochemical factors, including proteolytic enzymes, that lead to a breakdown of the cartilage macromolecules. Cytokines such as IL-1 and TNF-alpha produced by activated synoviocytes, mononuclear cells or by articular cartilage itself significantly up-regulate metalloproteinases (MMP) gene expression. Cytokines also blunt chondrocyte compensatory synthesis pathways required to restore the integrity of the degraded extrecellular matrix (ECM). Moreover, in OA synovium, a relative deficit in the production of natural antagonists of the IL-1 receptor (IL-1Ra) has been demonstrated, and could possibly be related to an excess production of nitric oxide in OA tissues. This, coupled with an upregulation in the receptor level, has been shown to be an additional enhancer of the catabolic effect of IL-1 in this disease.IL-1 and TNF-alpha significantly up-regulate MMP-3 steady-state mRNA derived from human synovium and chondrocytes. The neutralization of IL-1 and/or TNF-alpha up-regulation of MMP gene expression appears to be a logical development in the potential medical therapy of OA. Indeed, recombinant IL-1receptor antagonists (ILRa) and soluble IL-1 receptor proteins have been tested in both animal models of OA for modification of OA progression. Soluble IL-1Ra suppressed MMP-3 transcription in the rabbit synovial cell line HIG-82. Experimental evidence showing that neutralizing TNF-alpha suppressed cartilage degradation in arthritis also support such strategy. The important role of TNF-alpha in OA may emerge from the fact that human articular chondrocytes from OA cartilage expressed a significantly higher number of the p55 TNF-alpha receptor which could make OA cartilage particularly susceptible to TNF-alpha degradative stimuli. In addition, OA cartilage produces more TNF-alpha and TNF anglealpha convertase enzyme (TACE) mRNA than normal cartilage. By analogy, an inhibitor to the p55 TNF-alpha receptor may also provide a mechanism for abolishing TNF-alpha-induced degradation of cartilage ECM by MMPs. Since TACE is the regulator of TNF-alpha activity, limiting the activity of TACE might also prove efficacious in OA. IL-1 and TNF-alpha inhibition of chondrocyte compensatory biosynthesis pathways which further compromise cartilage repair must also be dealt with, perhaps by employing stimulatory agents such as transforming growth factor-beta or insulin-like growth factor-I. Certain cytokines have antiinflammatory properties. Three such cytokines - IL-4, IL-10, and IL-13 - have been identified as able to modulate various inflammatory processes. Their antiinflammatory potential, however, appears to depend greatly on the target cell. Interleukin-4 (IL-4) has been tested in vitro in OA tissue and has been shown to suppress the synthesis of both TNF-alpha and IL-1beta in the same manner as low-dose dexamethasone. Naturally occurring antiinflammatory cytokines such as IL-10 inhibit the synthesis of IL-1 and TNF-alpha and can be potential targets for therapy in OA. Augmenting inhibitor production in situ by gene therapy or supplementing it by injecting the recombinant protein is an attractive therapeutic target, although an in vivo assay in OA is not available, and its applicability has yet to be proven. Similarly, IL-13 significantly inhibits lipopolysaccharide (LPS)-induced TNF-alpha production by mononuclear cells from peripheral blood, but not in cells from inflamed synovial fluid. IL-13 has important biological activities: inhibition of the production of a wide range of proinflammatory cytokines in monocytes/macrophages, B cells, natural killer cells and endothelial cells, while increasing IL-1Ra production. In OA synovial membranes treated with LPS, IL-13 inhibited the synthesis of IL-1beta, TNF-alpha and stromelysin, while increasing IL-1Ra production.In summary, modulation of cytokines that control MMP gene up-regulation would appear to be fertile targets for drug development in the treatment of OA. Several studies illustrate the potential importance of modulating IL-1 activity as a means to reduce the progression of the structural changes in OA. In the experimental dog and rabbit models of OA, we have demonstrated that in vivo intraarticular injections of the IL-Ra gene can prevent the progression of structural changes in OA. Future directions in the research and treatment of osteoarthritis (OA) will be based on the emerging picture of pathophysiological events that modulate the initiation and progression of OA.
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PMID:The role of cytokines in osteoarthritis pathophysiology. 1208 86


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