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)

To study the effect of mononuclear cell differentiation on metalloproteinase production, the human monocytic cell lines U937 and THP-1 were exposed to two well known differentiating agents, the phorbol esters (phorbol myristate acetate (PMA)) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). With U937 cells, PMA-induced differentiation increased the production of both interstitial collagenase and 92-kDa gelatinase, whereas exposure to 1,25-(OH)2D3 induced full interstitial collagenase expression in the absence of any detectable 92-kDa gelatinase production. In fact, when U937 cells were differentiated with PMA and then exposed to vitamin D3, the hormone actually suppressed phorbol-induced 92-kDa gelatinase biosynthesis. With THP-1 cells, PMA also induced the production of 92-kDa gelatinase fully, but unlike U937 cells, the combination of PMA and 1,25-(OH)2D3 was required for substantial interstitial collagenase biosynthesis. As with U937 cells, the addition of 1,25-(OH)2D3 to PMA-differentiated THP-1 cells caused a dose-dependent inhibition of 92-kDa gelatinase production. Northern hybridizations demonstrated that both phorbol esters and vitamin D3 act on monocytic cell lines at a pretranslational level. To determine whether metalloproteinase biosynthesis in normal differentiated mononuclear phagocytes was also modified by 1,25-(OH)2D3, human blood monocytes and alveolar macrophages were exposed to this hormone. In both cell types, basal and Staphylococcal-stimulated 92-kDa gelatinase production was markedly inhibited by 1,25-(OH)2D3. In contrast, interstitial collagenase production was completely unaffected by the hormone. In summary, the two major metalloproteinases produced by monocytic cells are regulated via distinct molecular pathways by the action of PMA and 1,25-(OH)2D3. Furthermore, vitamin D3 completely dissociates the production of 92-kDa gelatinase and interstitial collagenase in human mononuclear phagocytes.
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PMID:1,25-dihydroxyvitamin D3 dissociates production of interstitial collagenase and 92-kDa gelatinase in human mononuclear phagocytes. 750 4

Degradation of elastic fibers in the arterial walls is an important step in the development of atherosclerosis. To identify the enzyme(s) responsible for the elastinolysis, we have designed an ex vivo model of aortic explants cultured with or without THP-1 cells (human monocyte/macrophage-like cells). After culturing with THP-1 cells for 5 days elastic fibers of the aortic explants were fragmented and lost. With insoluble [3H] elastin as a substrate, elastin-degrading activity could be detected in the culture medium. Zymography in sodium dodecyl sulfate-polyacrylamide gel electrophoresis containing alpha-elastin showed the presence of elastinolytic activity with 92 kd in the medium from the aortic tissue with THP-1 cell cultures, whereas the medium from the aortic tissue without THP-1 cells contained negligible elastinolytic activity. The activity was inhibited by ethylenediamine tetraacetic acid but not by phenylmethane sulfonyl fluoride, N-ethylmaleimide, or pepstatin A, indicating that the enzyme belongs to a class of metalloproteinases. In addition, destruction of the elastic fibers of the aortic explants cultured with THP-1 cells was completely inhibited only by metalloproteinase inhibitors. Immunoblot analyses demonstrated that the proteinase responsible for the elastinolytic activity is matrix metalloproteinase-9 (92-kd gelatinase/type IV collagenase = gelatinase B). Using immunocytochemistry, the metalloproteinase was localized in the THP-1 cells but not in the medial smooth muscle cells. These results suggest that matrix metalloproteinase-9 produced by THP-1 cells is of importance to degradation of elastic fibers in the aortic explants. The role of macrophages in the atherosclerosis is discussed with reference to elastinolysis of the arterial walls.
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PMID:Matrix metalloproteinase-9 (92-kd gelatinase/type IV collagenase equals gelatinase B) can degrade arterial elastin. 797 51

Monocytes and macrophages can modulate the turnover of extracellular matrix by producing metalloproteinases such as interstitial collagenase and 92-kDa gelatinase as well as tissue inhibitor of metalloproteinases. To study mechanisms of metalloproteinase induction in human mononuclear phagocytes, the effects of direct cell-cell contact between activated T lymphocytes and the human monocytic cell line THP-1 were determined. T cells were first activated with phorbol 12-myristate 13-acetate and phytohemagglutinin for 24 h, fixed with paraformaldehyde, and then exposed to THP-1 cells for 48 h. Upon contact with fixed activated T lymphocytes, a massive induction in the expression of both proteinases and tissue inhibitor of metalloproteinases was observed, whereas unstimulated T cells had no effect. Stimulation of metalloproteinase biosynthesis by THP-1 cells was mimicked by a membrane preparation derived from activated T cell lines, whereas cytosol and nuclear fractions of the T cells were ineffective. Furthermore, activated T lymphocytes exposed to trypsin, tunicamycin, or cycloheximide lost the capacity to stimulate THP-1 cells upon subsequent contact, implying the involvement of cell-surface glycoproteins. Similar induction of metalloproteinases by direct contact with activated T cells was also observed using normal blood monocytes as the target cells, and stimulation of monocyte metalloproteinases by T cell contact occurs at a pretranslational level. Consequently, cell-cell contact may represent an important biological mechanism for potentiating the inflammatory response that leads to extracellular matrix destruction.
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PMID:Direct contact between T lymphocytes and monocytes is a major pathway for induction of metalloproteinase expression. 807 24

The production of gelatinase B by macrophages is relevant in the immunological and migratory functions of macrophages. CGP 41251, an inhibitor of protein kinase C (PKC), was found to stimulate the expression of gelatinase B in macrophages, as shown by the study of two different monocytic/macrophagic cell lines, mouse RAW 264.7 and human THP-1 cells. When human monocytes and rat peritoneal macrophages were treated with CGP 41251, insignificant increases of 10 and 25% were obtained. This can possibly be due to the presence of contaminating cells in these two enriched populations, since the CGP 41251 treatment of non-macrophagic cell lines inhibited their PMA-induced gelatinase B production. Taken together, these results suggest that the stimulatory effect of CGP 41251 is specific to cells of the monocytic lineage. Using RAW 264.7 cells as a model, the effect of CGP 41251 is additive to that obtained using lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA), as revealed by gelatin zymography and Northern blot analysis. The stimulatory effect of CGP 41251 on gelatinase B production in RAW 264.7 was: (a) inhibited by calphostin C (as is the LPS-induced response), indicating a PKC-dependence; (b) inhibited by dexamethasone (as opposed to the LPS-induced response); and (c) enhanced by addition of trans-retinoic acid (RA). In fact, RA can induce gelatinase B production, either alone or in synergy with LPS and/or CGP 41251, since the combination of the three agents gives the highest gelatinase B response, at both the protein and the mRNA levels. This represents an important observation considering the RA is now being tested as an anti-cancer agent and proposed for prevention studies.
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PMID:Synergistic and selective stimulation of gelatinase B production in macrophages by lipopolysaccharide, trans-retinoic acid and CGP 41251, a protein kinase C regulator. 861 33

The 92 kDa matrix metalloproteinase (gelatinase B, MMP-9) plays a major role in the facilitation of tumor metastasis and in inflammatory disorders characterized by excessive matrix protein destruction. MMP-9 is transcriptionally induced in multiple cell types by exposure to the inflammatory mediators bacterial endotoxin, interleukin-1 (IL-1) or tumor necrosis factor-alpha (TNF-alpha). CT-2519, (1-(5-isothiocyanatohexyl)-3,7-dimethylxanthine), a synthetic small molecule from an anti-inflammatory compound library, was evaluated for its effect on endotoxin and cytokine-induced MMP-9 synthesis by a monocytic leukemic cell line, THP-1, and a monocyte/macrophage line, RAW 264.7. CT-2519 dose-dependently inhibited endotoxin and cytokine-induced synthesis of MMP-9 by these cells. Furthermore, both MMP-9 secretion and matrix invasion by cells of a human fibrosarcoma cell line, HT-1080, were inhibited by CT-2519 in a dose-dependent manner. Northern blot analyses and studies utilizing MMP-9 promoter constructs indicated that the inhibitory action of CT-2519 occurs at the level of transcriptional suppression. Given the observation that cellular activation by endotoxin, IL-1 and TNF-alpha may be mediated, at least in part, through induction of certain species of phosphatidic acid (PA), the effect of CT-2519 on lipid levels was analyzed. CT-2519 effectively reduced endotoxin-mediated increases in particular cellular lipid levels. Pharmacologic modulation of cytokine-dependent gene products, such as MMP-9, may offer an important therapeutic approach to the treatment of neoplastic and inflammatory disorders.
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PMID:Pharmacological inhibition of gelatinase B induction and tumor cell invasion. 875 12

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that directly control numerous genes of lipid metabolism by binding to response elements in the promoter. It has recently been proposed that PPARgamma may also regulate genes for proinflammatory proteins, not through PPRE binding but by interaction with transcription factors AP-1, STAT, and NF-kappaB. Recent studies with cultured human monocytes, however, have failed to observe an inhibitory effect of PPARgamma agonists on induced expression of TNFalpha and IL-6, genes known to be controlled by AP-1, STAT, and NF-kappaB. In a similar fashion, we show here that PPARalpha (fenofibrate) or PPARgamma (rosiglitazone) agonists failed to modulate LPS-induced secretion of IL-8 in THP-1 cells. When we made parallel observations on another gene, matrix metalloproteinase 9 (MMP-9), we were surprised to find profound downregulation of LPS-induced secretion by both PPARalpha or PPARgamma agonists. These findings suggest that PPAR may regulate only a subset of the proinflammatory genes controlled by AP-1, STAT, and NF-kappaB. Effects of PPARs on MMP-9 may account for the beneficial effect of PPAR agonists in animal models of atherosclerosis.
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PMID:Activation of PPARalpha or gamma reduces secretion of matrix metalloproteinase 9 but not interleukin 8 from human monocytic THP-1 cells. 1062 22

Macrophages secrete matrix metalloproteinase 9 (MMP-9), an enzyme that weakens the fibrous cap of atherosclerotic plaques, predisposing them to plaque rupture and subsequent ischemic events. Recent work indicates that statins strongly reduce the possibility of heart attack. Furthermore, these compounds appear to exert beneficial effects not only by lowering plasma low-density-lipoprotein cholesterol but also by directly affecting the artery wall. To evaluate whether statins influence the proinflammatory responses of monocytic cells, we studied their effects on the chemotactic migration and MMP-9 secretion of human monocytic cell line THP-1. Simvastatin dose dependently inhibited THP-1 cell migration mediated by monocyte chemoattractant protein 1, with a 50% inhibitory concentration of about 50 nM. It also inhibited bacterial lipopolysaccharide-stimulated secretion of MMP-9. The effects of simvastatin were completely reversed by mevalonate and its derivatives, farnesylpyrophosphate and geranylgeranyl pyrophosphate, but not by ubiquinone. Additional studies revealed similar but more profound inhibitory effects with L-839,867, a specific inhibitor of geranylgeranyl transferase. However, alpha-hydroxyfarnesyl phosphonic acid, an inhibitor of farnesyl transferase, had no effect. C3 exoenzyme, a specific inhibitor of the prenylated small signaling Rho proteins, mimicked the inhibitory effects of simvastatin and L-839,867. These data supported the role of geranylgeranylation in the migration and MMP-9 secretion of monocytes.
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PMID:Statins suppress THP-1 cell migration and secretion of matrix metalloproteinase 9 by inhibiting geranylgeranylation. 1140 82

It is shown that the release of matrix metalloproteinase-9 (gelatinase B) by THP-1 and U937 cells into conditioned media is increased under the action of recombinant single-chain urokinase. This effect is not accompanied by proteolytic activation of gelatinase B and is related to release of a pro-form of the enzyme. The action of urokinase on monocytes is time-dependent and becomes significant 12-24 h after the beginning of cell incubation. The dependence of the effect on the concentration of urokinase is characterized by half-maximum at about 20 nM and saturation at about 200 nM. The urokinase-induced gelatinase B release is not dependent on the action of plasmin because plasmin inhibitors aprotinin and alpha2-antiplasmin do not abolish this action. Additionally, tissue type plasminogen activator does not induce gelatinase B release by monocytes as observed under the action of urokinase. Nevertheless, the catalytic activity of urokinase participates in the development of the observed effect because it is significantly depressed by the natural urokinase inhibitor PAI-1. The effect of urokinase is completely abolished by actinomycin D and cycloheximide, indicating the participation of transcription and translation processes in its development.
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PMID:Plasmin-independent gelatinase B (matrix metalloproteinase-9) release by monocytes under the influence of urokinase. 1170 74

Platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) and gelatinase B are coexpressed at sites of inflammation, where an intense interaction occurs between leukocytes and endothelial cells. To investigate whether a functional link exists between PECAM-1 activation and gelatinase B production, the regulatory role of PECAM-1, IFN-gamma, IFN-beta, LPS, and PMA on the production of gelatinase B (MMP-9) was studied in vitro in normal human umbilical vein endothelial cells (HUVECs), human peripheral blood mononuclear cells (PBMCs), and in a human monocytic leukemia cell line. In THP-1 cells, progelatinase B levels were slightly up-regulated by immobilized PECAM-1-specific monoclonal antibody (mAb) and soluble recombinant PECAM-1 when compared with strong induction by LPS and PMA. IFN-beta inhibited the induced and basal gelatinase B production but had no modulating effect on the expression of PECAM-1. HUVECs mainly produced progelatinase A (proMMP-2). Treatment with LPS and triggering of the endothelial cells with PECAM-1 mAb or recombinant PECAM-1 had no effect on gelatinase A or B production, whereas PMA stimulated the production of progelatinase B. IFN-beta significantly up-regulated the expression of PECAM-1 in HUVECs but did not affect gelatinase secretion. Finally, in PBMCs, progelatinase B production was increased by soluble PECAM-1 mAb, recombinant PECAM-1, LPS, and PMA, whereas IFN-beta reduced gelatinase B secretion. IFN-beta did not alter PECAM-1 expression on PBMCs. Thus, PECAM-1 and gelatinase B are differently regulated in leukocytes and endothelial cells.
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PMID:Regulation of gelatinase B in human monocytic and endothelial cells by PECAM-1 ligation and its modulation by interferon-beta. 1178 84

Urokinase-type plasminogen activator (uPA) is suggested to exert its proliferatory, migratory and invasive action through binding with its membrane receptor, promoting pericellular proteolysis and mediating cell signal transduction. One of the possible actions of urokinase can be related to the regulation of activity and/or the expression of proteolytic enzymes participating in extracellular matrix degradation. In the present study, the role of uPA in regulating matrix metalloproteinase (MMP) expression and release by the monocyte cell line THP-1 was investigated. Recombinant uPA induced the release of MMP9/gelatinase B, as detected by zymography and Western blotting, and this release was abolished by actinomycin D and cycloheximide (inhibitors of DNA transcription and protein synthesis) and partially suppressed by monensin (an inhibitor of secretion). Proteolytically inactive urokinase with substitution of His(204) for Gln was able to reproduce about 70% of the effect induced by the wild-type recombinant uPA. The reverse transcription-PCR and Northern blot data indicated that the action of r-uPA on THP-1 cells resulted in formation of MMP9 mRNA, which depended on time, within 6-48 h, of the cell incubation with r-uPA. These results suggest that urokinase upregulates MMP9 expression in monocytes via MMP9 gene transcription and protein biosynthesis.
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PMID:Urokinase upregulates matrix metalloproteinase-9 expression in THP-1 monocytes via gene transcription and protein synthesis. 1211 12


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