Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Extracellular matrix degradation by secreted proteases, e.g. plasmin, is essential for endometrial functions such as blastocyst implantation and menstruation. We investigated whether the expression of plasmin(ogen) activating or inhibiting factors in endometrial cells from women with endometriosis was different from women without the disease. Endometrial biopsies were obtained from 10 patients with and 16 women without endometriosis. Cells were cultured in Dulbecco's modified Eagle's medium (DMEM)/F12 supplemented with diethylstilboestrol (10(-10) M) alone or combined with promegestone (5 x 10(-8) or 5 x 10(-6) M). Urokinase plasminogen activator (uPA), plasminogen activator inhibitor (PAI)-1 and -2, and soluble uPA receptor (suPA-R) concentrations were assayed by enzyme-linked immunosorbent assay (ELISA) in the conditioned media. uPA and PAI-2 concentrations were not influenced by steroid treatment and did not differ between women with and without endometriosis, whereas PAI-1 was significantly up-regulated by promegestone in both groups. In contrast, suPA-R expression was not influenced by steroid treatment but was significantly higher in cells from endometriosis patients. This is the first report on suPA-R secretion in endometrial cells and the results indicate an altered activation of plasmin(ogen) in endometrium from women with endometriosis that could lead to a higher proteolytic potential of retrogradely menstruated endometrial fragments with consecutive development of endometriotic foci.
Mol Hum Reprod 1997 Dec
PMID:Soluble urokinase-type plasminogen activator receptor is over-expressed in uterine endometrium from women with endometriosis. 946 55

As several forms of lung injury are associated with alveolar fibrin deposition, and fibrin has been pathogenically implicated in the lung fibrotic response, we sought to develop an in vivo gene transfer model of fibrinolytic protease overexpression. To this end, human tissue-type plasminogen activator (t-PA) possesses a high degree of specificity for proteolytic activation of fibrin-bound plasminogen to its active form, plasmin. To construct an effective vector, the cDNA for human t-PA was inserted downstream of a cytomegalovirus early enhancer-promoter into the E1 position of a replication-deficient adenovirus. The adenovirally expressed t-PA was found to be of the expected size and appropriate functional activity both in vitro and in vivo. A single intratracheal instillation of the adenoviral-t-PA construct resulted in a dose- dependent, tissue-specific expression of increased levels of t-PA antigen (100-fold) and t-PA protease activity (4-fold) for at least 2 wk in whole lung lysates. The expressed protein localized to the bronchiolar epithelium and peribronchiolar alveolar cells and did not result in increases in total lung protein or alveolar cell counts at 3 d after instillation. In conclusion, a single intratracheal instillation of adenoviral-cytomegalovirus-t-PA construct will generate dramatic bronchoalveolar compartment overexpression of functional recombinant human t-PA for at least 2 wk. This vector can now be utilized for the determination of the therapeutic potential of t-PA in a number of in vivo model systems.
Am J Respir Cell Mol Biol 1998 Mar
PMID:Adenovirally mediated gene transfer of functional human tissue-type plasminogen activator to murine lungs. 949 Jun 48

We previously reported that ascorbate (vitamin C) can regulate the growth of cultured vascular smooth muscle cells (VSMC) directly as well as by altering the properties of extracellular matrix (ECM) [Mol Cell Cardiol 1997;29:3293-303]. In the present study we compared the effects of ascorbate and transforming growth factor-beta 1 (TGF-beta1) on VSMC growth in order to determine whether their actions were mediated by similar mechanisms. When VSMC proliferation was stimulated by fetal bovine serum, the addition of TGF-beta1 (20 ng/ml) or ascorbate (1 mM) to the cell culture medium inhibited the cellular incorporation of [3H]thymidine by 19 and 59%, respectively, and by 85% when added together. The cell growth inhibitory effects of TGF-beta1 and ascorbate were partially mediated by changing the growth-regulatory properties of the ECM produced by the cells. Thus, VSMC grew more slowly on ECM deposited by VSMC under treatment with 20 ng/ml TGF-beta1 or 1 mM ascorbate (52 and 46% inhibition, respectively) than on control ECM, and their combination had an additional inhibitory effect (84%). Anti-TGF-beta1 neutralizing antibodies prevented the direct and ECM-mediated effects of TGF-beta1 on VSMC growth, but did not alter the effects of ascorbate. When ECM was pre-incubated with increasing concentrations of TGF-beta1, the growth rate of freshly plated VSMC gradually decreased, indicating that ECM-bound TGF-beta1 retained its biological activity. Comparison of the patterns of TGF-betal binding to ECM produced by VSMC in the presence or absence of ascorbate revealed no significant differences. Extraction of ECM-bound TGF-beta1 by incubation of exposed ECM with plasmin did not affect the ECM-mediated inhibitory effect of ascorbate, as the rate of proliferation of secondary VSMC cultures grown on ascorbate-dependent and independent matrices treated with plasmin were equally increased. These results suggest that the amount of ECM-bound TGF-beta1 was not altered by ascorbate. The secretion of TGF-beta1 into the cell culture medium by VSMC also did not depend on the ascorbate supply. Finally, addition of heparin to the VSMC culture medium during ECM production abolished the ECM-mediated growth inhibitory effects of ascorbate, but did not affect the action of TGF-beta1. Our data demonstrate that the growth inhibitory effects of ascorbate on cultured VSMC are independent of the action of TGF-beta1, and the effects of these two compounds on VSMC growth are additive.
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PMID:Transforming growth factor-beta 1 and ascorbate regulate proliferation of cultured smooth muscle cells by independent mechanisms. 973 12

Escherichia coli strains carrying recombinant plasmids encoding either the type 1 fimbria of Salmonella enterica serovar Typhimurium or the G fimbria of E. coli exhibited binding of human 125I-Glu-plasminogen and enhanced the tissue-type plasminogen activator-catalyzed conversion of plasminogen to plasmin. Purified type 1 or G fimbriae similarly bound plasminogen and enhanced its activation. The binding of plasminogen did not involve the characteristic carbohydrate-binding property of the fimbriae but was inhibited at low concentrations by the lysine analog epsilon-aminocaproic acid. Because these fimbrial types bind to laminin of basement membranes (M. Kukkonen et al., Mol. Microbiol. 7:229-237, 1993; S. Saarela et al., Infect. Immun. 64:2857-2860, 1996), the results demonstrate a structural unity in the creation and targeting of bacterium-bound proteolytic plasmin activity to basement membranes.
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PMID:Identification of two laminin-binding fimbriae, the type 1 fimbria of Salmonella enterica serovar typhimurium and the G fimbria of Escherichia coli, as plasminogen receptors. 974 4

Effects of bovine plasmin and plasminogen activator recovered from bovine embryo-conditioned medium (bePA) on the polypeptide profile and solubility of bovine zonae pellucidae (ZP) were evaluated. ZP were isolated from bovine ovarian oocytes and incubated at 39 degrees C with 0, 100, or 200 microg/ml plasmin for 0, 24, or 48 hr or bePA with 0 or 100 microg/ml human plasminogen for 0 or 48 hr. ZP were evaluated either by SDS-PAGE or for changes in solubility using a zona pellucida dissolution time (ZPDT) assay. Two prominent polypeptides, molecular weight (MW) 76,000 and 65,000, and two minor polypeptides, MW 23,000 and 22,000, were resolved by SDS-PAGE. No changes occurred in the polypeptide profile for ZP incubated with 0 microg/ml plasmin for 0, 24, or 48 hr, and ZPDT did not differ (P > 0.10). Treatment with 100 or 200 microg/ml plasmin induced reductions in the MW 76,000, 23,000, and 22,000 polypeptides and the appearance of MW 45,000 and <10,000 polypeptides. ZPDT were less (P < 0.05) in 100 and 200 microg/ml compared with 0 microg/ml plasmin. Polypeptide profiles and ZPDT for ZP incubated with bePA were similar (P > 0.10) to ZP incubated with unconditioned medium. Addition of human plasminogen to ZP incubated with bePA reduced the MW 76,000, 23,000, and 22,000 polypeptides, caused the appearance of MW 45,000 and 20,000 polypeptides, and decreased ZPDT (P < 0.05). These results demonstrate that bovine plasmin is capable of proteolytically degrading the bovine ZP and that bePA can indirectly affect the ZP by converting plasminogen to plasmin.
Mol Reprod Dev 1998 Nov
PMID:Changes in the bovine zona pellucida induced by plasmin or embryonic plasminogen activator. 977 54

Fibrinolysis is essential for maintaining the fluency of blood flow. Attenuated fibrinolytic activity has been frequently detected in coronary artery disease, peripheral vascular diseases, diabetes, hyperlipidaemia and obesity. The biologically active product of fibrinolytic system is plasmin. Generation of plasmin is regulated by plasminogen activators (PA) and their inhibitors (PAI). Vascular endothelial and smooth muscle cells synthesize tissue-type and urokinase-type PA (tPA and uPA) and their major physiological inhibitor, PAI-1. The production of fibrinolytic regulators is modulated by a number of biological factors related to thrombosis and atherosclerosis, including coagulation factors, hormones, growth factors, inflammatory mediators and lipoproteins. Several anticoagulants, including heparin, hirudin and hirulog-1, affect the production of fibrinolytic regulators in vascular cells. Studies in knockout mice demonstrated that mice deficient in PA or plasminogen are susceptible to thrombosis during inflammation or injury. Overexpression of uPA or deficiency of PAI-1 promotes neointima and aneurysm formation, which is probably due to active remodelling of extracellular matrix in vascular wall caused by excess plasmin. Long-term effect of treatment with thrombolytic agents or in atheroscleronic cardiovascular diseases remains to be defined. Future studies on determination of the role of PA and PAI in vascular remodelling may help understand the mechanism for neointima formation and orient the prevention of restenosis following vascular procedures.
Int J Mol Med 1998 Feb
PMID:Vascular cell-derived fibrinolytic regulators and atherothrombotic vascular disorders (Review). 985 42

Mesangial cells are pericyte-like cells which are found the glomeruli of the kidney. It is well known that they have important contractile and synthetic properties regulating the function of the glomerulus. During diabetes the synthesis of various extracellular matrix (ECM) components by mesangial cells are increased. In recent years it has been recognized that degradation of ECM may also be decreased in diabetes, contributing to the process of mesangium accumulation. The major enzymes responsible for ECM degradation are a large group of enzymes collectively known as matrix metalloproteinases (MMPs). The physiology of MMPs is complex and their activity is tightly regulated at many levels. The MMPs are synthesized as proenzymes and require activation via catalytic cleavage to become fully active. In this regard it is of importance that the mesangial cell and its pericellular matrix have a very active plasminogen cascade that can liberate plasmin locally to mediate matrix degradation both directly and indirectly, by activating the MMPs. In addition, the MMPs are regulated by transforming growth factor beta (TGF-beta). There is evidence that each of these pathways regulating the matrix degradation is affected by the diabetic environment and this will be the subject of this contribution.
Cell Mol Biol (Noisy-le-grand) 1999 Feb
PMID:The role of the mesangial cell and its matrix in the pathogenesis of diabetic nephropathy. 1009 46

Basement membrane transmigration is an important step in tissue recruitment of eosinophils into inflamed tissue. Recent reports showed that this phenomenon is modulated by platelet-activating factor (PAF) in combination with cytokines and proteinases. We investigated the in vitro efficacy of 5-oxo-6,8,11, 14-eicosatetraenoic acid (5-oxo-ETE), a metabolite of arachidonic acid and known as a potent eosinophil chemotactic factor, in promoting the transmigration of blood eosinophils from normal and asthmatic subjects through a Matrigel basement membrane. 5-Oxo-ETE proved to be a more potent (> 10-fold) inducer of eosinophil transmigration than PAF, and this effect was similar in cells from normal and asthmatic subjects (82.0 +/- 3.7% and 88.1 +/- 3.7%, respectively). Moreover, 5-oxo-ETE was active in the absence of interleukin (IL)-5, although this cytokine amplified the effect of 5-oxo-ETE from 61.3 +/- 3.3% to 92.8 +/- 1.8% (p = 0.003). The membrane receptor for urokinase plasminogen activator (CD87), a serine protease, was observed on eosinophils, and its expression was increased by IL-5. The inhibition of both metalloproteinases (MMP) and plasmin/plasminogen complex with inhibitor or monoclonal antibodies decreased cell transmigration by about 50%. Combination of an MMP inhibitor with anti-CD87 antibodies had no additive effect. These data show that 5-oxo-ETE is an efficient promoter of eosinophil transmigration in vitro, and is much more potent in this respect than PAF. The data suggest that 5-oxo-ETE could play an important role in eosinophil recruitment in vivo. Moreover, they demonstrate that in addition to MMP, the plasmin/plasminogen system could be involved in eosinophil transmigration.
Am J Respir Cell Mol Biol 1999 Jul
PMID:5-Oxo-6,8,11,14-eicosatetraenoic acid induces important eosinophil transmigration through basement membrane components: comparison of normal and asthmatic eosinophils. 1038 97

During co-evolution of interacting proteins, functionally disruptive mutations on one side of the interface may be compensated by local amino acid changes on the other to restore binding affinity. This information can be useful for geometry-based docking approaches by reducing the translational and rotational space available to the proteins. Here, we demonstrate that correlated mutations at a protein-protein interface can be rapidly identified by selecting a phage-displayed library of a randomly mutated component of the complex for complementation of mutations that decreased binding in the interacting partner. This approach was used to deduce the binding mode of staphylokinase (Sak), a 15.5 kDa "indirect" plasminogen activator on microplasmin (microPli), the 28 kDa serine protease domain of plasmin. Biopanning indicated that residues Arg94 and Gly174 in microPli are located in close proximity to Glu75 and the Glu88:Ile128 pair in Sak, respectively. The coupled mutations Glu94<-->Lys75 reversed and Gly174<-->Lys88:Val128 introduced a salt bridge, whereby the binding affinities (with coupling energies of 1.8 to 2.3 kcal mol-1, respectively) and the plasminogen activation ability of the mutated complexes were partially restored. These findings suggested a unique docking mode of Sak at the western rim of the active-site cleft of microPli, that is in agreement with the structure of the Sak-microPli complex as recently derived by other methods.
J Mol Biol 1999 Jul 09
PMID:Guiding a docking mode by phage display: selection of correlated mutations at the staphylokinase-plasmin interface. 1039 Mar 45

In order to define the relative contribution of the proteolytic domain and the receptor-binding domain of urokinase plasminogen activator (uPA) toward its mitogenic properties we studied the effects of different uPA isoforms on migration and proliferation of human aortic smooth muscle cells (hSMC). The isoforms tested included native human glycosylated uPA, and two recombinant uPA forms, namely a recombinant uPA with wild type structure (r-uPA), and a uPA-mutant in which the first 24 N-terminal amino acid residues of the receptor binding domain were replaced by 13 foreign amino acid residues (r-uPAmut). Cell migration was evaluated using a micro-Boyden chamber assay, and cell proliferation assessed by measurement of [3H]-thymidine incorporation into DNA. Competition binding studies on hSMC using 125I-r-uPA as ligand demonstrated that r-uPA and r-uPAmut exhibited equivalent displacement profiles. However, migration of hSMC was promoted by r-uPA and not by r-uPAmut. r-uPA-induced migration occurred at concentrations (half-maximally effective concentration of 2 nM) approximating the Kd for uPA-uPAR binding (1 nM). r-uPA-induced migration was not affected by the plasmin inhibitor aprotinin. In contrast to their differential chemotactic properties, uPA, r-uPA and r-uPAmut, which possess similar proteolytic activities, all stimulated [3H]-thymidine incorporation in hSMC. Since the [3H]-thymidine incorporation response to each isoform occurred at concentrations (> 50 nM) much higher than necessary for uPAR saturation by ligand (1 nM), this mitogenic response may be independent of binding to uPAR. [3H]-thymidine incorporation responses to r-uPA and -uPAmut were sensitive to the plasmin inhibitor aprotinin, and uPA stimulated DNA synthesis was inhibited by plasminogen activator inhibitor. We conclude that hSMC migration in response to uPA depends upon on its binding to uPAR, whereas uPA-stimulated DNA synthesis in these cells requires proteolysis and plasmin generation.
Mol Cell Biochem 1999 May
PMID:Urokinase plasminogen activator induces human smooth muscle cell migration and proliferation via distinct receptor-dependent and proteolysis-dependent mechanisms. 1039 84


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