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)

To investigate the role of tumor necrosis factor-alpha (TNF alpha) in advanced collagenolysis and degradation of connective tissue components in preterm parturition, the effects of human recombinant TNF alpha (hrTNF alpha) on the production of matrix metalloproteinase 1 (MMP-1)/tissue collagenase, MMP-3/stromelysin, tissue inhibitor of metalloproteinases (TIMP), urokinase type-plasminogen activator (uPa) and prostaglandin (PG) E2 in human chorionic cells were examined in vitro. Human chorionic cells, but not amniotic cells, were found to respond to macrophage-conditioned medium (contains mainly interleukin 1) to produce MMP-1 and MMP-3. This indicated that the chorionic cell is one of the MMP-producing cells of fetal membranes. When confluent chorionic cells were treated with hrTNF alpha, the production of MMP-1 and MMP-3 as well as of uPa and PGE2 was greatly increased in a dose-dependent manner. In contrast, the production of TIMP was suppressed by hrTNF alpha. These results suggested that TNF alpha may participate in destruction of collagen and other connective tissue matrix components of fetal membranes and in promotion of uterine contractility in preterm parturition with intraamniotic infection.
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PMID:Tumor necrosis factor-alpha stimulates the biosynthesis of matrix metalloproteinases and plasminogen activator in cultured human chorionic cells. 131 22

Tumor necrosis factor-alpha (TNF-alpha) is released from a cell membrane-anchored precursor by proteolytic cleavage. We have shown that broad spectrum synthetic inhibitors of matrix metalloproteinases (MMPs) prevent the processing of the TNF precursor but do not inhibit the release of other cytokines. Purified MMPs, stromelysin, matrilysin, collagenase, and the gelatinases can all cleave a recombinant pro-TNF substrate to yield mature TNF. MMP inhibitors prevent the rise in blood levels of TNF after endotoxin administration in rats and are effective in animal models of inflammatory disease such as adjuvant arthritis. Drugs that inhibit MMP action and TNF release show great promise for the treatment of autoimmune inflammatory diseases.
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PMID:Matrix metalloproteinases and processing of pro-TNF-alpha. 775 57

We have examined the correlation between matrix metalloproteinase (MMP) expression and metastatic properties of a low metastatic osteosarcoma cell line, osteosarcoma takase (OST), under stimulation by tumour necrosis factor alpha (TNF alpha). In vivo, OST cells exhibited significantly increased colonization in the lungs of nude mice in a dose-dependent manner when they were treated by TNF alpha prior to injection. In vitro, TNF alpha enhanced tumour cell invasion through the reconstituted basement membrane in a transwell chamber up to 2.5-fold. Gelatin zymography and sandwich enzyme immunoassays demonstrated marked production of MMP-9 [92-kDa gelatinase/type IV collagenase (gelatinase B)] but not MMP-2 [72-kDa gelatinase/type IV collagenase (gelatinase A)], MMP-3 (stromelysin-1) or MMP-7 (matrilysin). Motility of the tumour cells and adhesion to cultured endothelial cells were slightly increased by the TNF alpha treatment up to 1.6-fold and 1.4-fold, respectively, while the growth rate was decreased. These results suggest that upregulation of MMP-9 together with enhanced motility and endothelial adhesion contribute to the increased metastatic ability of OST cells induced by TNF alpha treatment.
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PMID:Expression of matrix metalloproteinase 9 (92-kDa gelatinase/type IV collagenase) induced by tumour necrosis factor alpha correlates with metastatic ability in a human osteosarcoma cell line. 803 35

Matrix metalloproteinases (MMPs) play a role in tissue remodelling and angiogenesis. We have investigated the expression and regulation of MMP-1 (interstitial collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin 1), MMP-7 (matrilysin), MMP-9 (gelatinase B) and their inhibitors TIMP-1 and TIMP-2 in human umbilical vein, femoral vein and microvascular endothelial cells, and compared these data with those obtained with human synovial fibroblasts. Non-stimulated vein endothelial cells expressed the mRNAs for MMP-1, MMP-2, TIMP-1 and TIMP-2. MMP-3 mRNA and protein were undetectable or only weakly expressed, but could be stimulated by the inflammatory mediator tumour necrosis factor alpha (TNF alpha). The expression of MMP-3 and MMP-1 was further enhanced by phorbol 12-myristate 13-acetate (PMA). Phorbol ester also induced TIMP-1 and MMP-9, the expression of the latter being further enhanced by TNF alpha or interleukin 1 alpha (IL-1 alpha). Similar stimulatory effects were observed in microvascular endothelial cells. Hence the inflammatory mediator TNF alpha induces/enhances the production of several matrix metalloproteinases in human endothelial cells. On the other hand, MMP-2 and TIMP-2 were not affected or were affected in a variable way by TNF alpha and/or phorbol ester, suggesting a dissimilar regulation of these proteins. The cyclic AMP-enhancing agent forskolin affected the production of MMPs in a cell-type-specific way. In human vein endothelial cells it enhanced the PMA-mediated induction of MMP-9, whereas it suppressed this induction in human microvascular endothelial cells and in synovial fibroblasts. On the other hand, forskolin suppressed the PMA-mediated induction of MMP-1 and MMP-3 in synovial fibroblasts, while it enhanced or did not affect this induction in various types of human endothelial cells. These observations may have implications for future pharmacological intervention in angiogenesis.
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PMID:Regulation of matrix metalloproteinase expression in human vein and microvascular endothelial cells. Effects of tumour necrosis factor alpha, interleukin 1 and phorbol ester. 828 80

Matrix metalloproteinases (MMPs) are a large family of Zn2+ endopeptidases that are expressed in inflammatory conditions and are capable of degrading connective tissue macromolecules. MMP-like enzymes are also involved in the processing of a variety of cell surface molecules including the pro-inflammatory cytokine TNF-alpha. MMPs and TNF-alpha have both been implicated in the pathology associated with neuro-inflammatory diseases (NIDs), particularly multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). We have shown that BB-1101, a broad spectrum hydroxamic acid-based combined inhibitor of MMP activity and TNF processing, reduces the clinical signs and weight loss in an acute EAE model in Lewis rats. However, little is known about which MMPs are involved in the neuroinflammatory process. In order to determine the optimum inhibitory profile for an MMP inhibitor in the treatment of NID, we investigated the profile of MMP expression and activity during EAE. The development of disease symptoms was associated with a 3-fold increase in MMP activity in the cerebrospinal fluid (CSF), which could be inhibited by treatment with BB-1101, and an increase in 92 kDa gelatinase activity detected by gelatin substrate zymography. Quantitative PCR analysis of normal and EAE spinal cord revealed the expression of at least seven MMPs. Of these, matrilysin showed the most significant change, being elevated over 500 fold with onset of clinical symptoms and peaking at maximum disease severity. Of the other six MMPs detected, 92 kDa gelatinase showed a modest 5 fold increase which peaked at the onset of clinical signs and then declined during the most severe phase of the disease. Matrilysin was localised by immunohistochemistry to the invading macrophages within the inflammatory lesions of the spinal cord. Matrilysin's potent broad spectrum proteolytic activity and its localisation to inflammatory lesions in the CNS suggest this enzyme could be particularly involved in the pathological processes associated with neuro-inflammatory disease.
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PMID:Matrix metalloproteinase expression during experimental autoimmune encephalomyelitis and effects of a combined matrix metalloproteinase and tumour necrosis factor-alpha inhibitor. 911 83

The matrix metalloproteinase matrilysin (MMP-7) has been demonstrated to contribute to tumor development. We have shown previously that members of the TNF family of apoptosis-inducing proteins are substrates for this enzyme, resulting in increased death pathway signaling. The goal of the current study was to reconcile the proapoptotic and tumor-promoting functions of matrilysin. In the human HBL100 and murine NMuMG cell lines that represent early stages of tumor progression and that express both Fas ligand and its receptor, exposure to matrilysin results in cell death that can be blocked by FasL neutralizing antibodies. Constitutive expression of matrilysin in these cell lines selects for cells with reduced sensitivity to Fas-mediated apoptosis as demonstrated both with a receptor-activating antibody and with in vitro activated splenocytes. Matrilysin-expressing cells are also significantly less sensitive to chemical inducers of apoptosis. We propose that the expression of matrilysin that has been reported at early stages in various tumor types can act to select cells with a significantly decreased chance of removal due to immune surveillance. As a result, these cells are more likely to acquire additional genetic modifications and develop further as tumors.
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PMID:Matrilysin [MMP-7] expression selects for cells with reduced sensitivity to apoptosis. 1177 28

Fas Ligand (FasL) is a member of the TNF superfamily that induces apoptosis in susceptible cells upon cross-linking of its own receptor, Fas (Apo-1/CD95). FasL-induced apoptosis contributes to immune homeostasis and cell-mediated cytotoxicity. Several groups have suggested that it also participates in the mechanism of action of DNA-damaging anticancer drugs. However, others have disputed this hypothesis, based largely on the inability of exogenously added anti-Fas/FasL reagents to attenuate drug-induced apoptosis in their studies. In this minireview, we discuss the most recent evidence for and against the involvement of FasL/Fas in the sensitivity and resistance to chemotherapy in a variety of models. In our own model of Ewing's sarcoma (ES), we have extensively investigated the involvement of the FasL/Fas pathway in doxorubicin (Dox)-induced apoptosis. We have generated clones of the Fas-sensitive, Dox-sensitive ES cell line SK-N-MC that were either Fas-resistant or FasL-deficient, and found that they were significantly resistant to Dox. Cleavage of FasL by MMP-7 (matrilysin) protected the parental SK-N-MC cells from Dox, whereas inhibition of MMP-7 activity increased their sensitivity. Transfection of a construct encoding soluble (decoy) Fas protected SK-N-MC cells from Dox. However, incubation with anti-Fas or anti-FasL neutralizing antibodies or exogenous addition of pre-synthesized recombinant soluble Fas decoy protein had no protective effect. This raises the possibility that the proposed Fas/FasL suicidal interaction may take place in an intracellular compartment and thus is not accessible to exogenously added reagents. Therefore, commercially available Fas/FasL neutralizing reagents may not be a reliable indicator of the involvement of the Fas pathway in anticancer-drug-induced apoptosis and experiments using these agents should be carefully re-evaluated. The combined use of MMP inhibitors with conventional, cytotoxic chemotherapy may hold therapeutic benefit.
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PMID:The role of Fas and FasL as mediators of anticancer chemotherapy. 1199 78

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

TNF alpha converting enzyme (TACE) processes precursor TNF alpha between Ala76 and Val77, yielding a correctly processed bioactive 17 kDa protein. Genetic evidence indicates that TACE may also be involved in the shedding of other ectodomains. Here we show that native and recombinant forms of TACE efficiently processed a synthetic substrate corresponding to the TNF alpha cleavage site only. For all other substrates, conversion occurred only at high enzyme concentrations and prolonged reaction times. Often, cleavage under those conditions was accompanied by nonspecific reactions. We also compared TNF alpha cleavage by TACE to cleavage by those members of the matrix metalloproteinase (MMP) family previously implied in TNF alpha release. The specificity constants for TNF alpha cleavage by the MMPs were approximately 100-1000-fold slower relative to TACE. MMP 7 also processed precursor TNF alpha at the correct cleavage site but did so with a 30-fold lower specificity constant relative to TACE. In contrast, MMP 1 processed precursor TNF alpha between Ala74 and Gln75, in addition to between Ala76 and Val77, while MMP 9 cleaved this natural substrate solely between Ala74 and Gln75. Additionally, the MMP substrate Dnp-PChaGC(Me)HK(NMA)-NH(2) was not cleaved at all by TACE, while collagenase (MMP 1), gelatinase (MMP 9), stromelysin 1 (MMP 3), and matrilysin (MMP 7) all processed this substrate efficiently. All of these results indicate that TACE is unique in terms of its specificity requirements for substrate cleavage.
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PMID:The tumor necrosis factor-alpha converting enzyme (TACE): a unique metalloproteinase with highly defined substrate selectivity. 1213 69

Langerhans cells (LC) are dendritic cells that capture foreign antigens and migrate with them to the regional lymph nodes where they are presented to naive T cells. The possible role of matrix metalloproteinase-9 (MMP-9) in migration was suggested following experiments in a mouse model and in human skin explants. Using in vitro generated LC (iLC) derived from CD34+ cord blood cells and epidermal LC (eLC), we investigated the correlation between MMP-9 and other MMPs production and cell migration. Cells were activated by Bandrowski's base (BB), a chemical allergen, or by recombinant birch pollen allergen 1 (rBetv 1). Contact with allergens triggered migration of these cells, with a maximum rate being reached after 24 h. Migration was preceded by production of MMP-2 and MMP-9; part of the molecules were recovered as pro-MMPs in cell culture supernatant and part were associated with cell membrane proteins. At the cellular level, membrane-type 1 (MT1) and MT3-MMP were also identified. Addition of tumor necrosis factor-alpha (TNF-alpha) initiated pro-MMP-2 and pro-MMP-9 production followed by cell migration in a dose-dependent manner. These data imply that TNF-alpha is a key molecule for MMP production and cell migration. Furthermore, activation of iLC with BB or rBet v 1 induced synthesis of TNF-a and expression of TNF RII on the cell membrane, suggesting an autocrine loop. In conclusion, membrane-associated MMP-2 and-9 rather than soluble MMPs appear to be involved in cell migration.
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PMID:Relationship between expression of matrix metalloproteinases and migration of epidermal and in vitro generated Langerhans cells. 1216 Jan 46


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