Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.68 (tissue plasminogen activator)
 11,311 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study we determined the in vitro effects of polysulfated glycosaminoglycan (PSGAG) and the glucocorticoid triamcinolone acetonid (TA) on the IL-1 altered expression and activity of matrix metalloproteinases (MMP-1, MMP-3), tissue inhibitor of metalloproteinases-1, the plasminogen activators tPA and uPA and plasminogen activator inhibitor 1 by articular chondrocytes. Bovine chondrocytes were cultured in alginate gel beads. Cells were treated with interleukin-1alpha (IL-1alpha) in the presence of vehicle or drugs at various concentrations. After 48hr mRNA expression of MMP-1, MMP-3, TIMP-1, uPA, tPA and PAI-1 was analyzed by RT-PCR-ELISA. The protein synthesis of TIMP-1 and MMP-3 was determined by immunoprecipitation, PAI-1 protein was quantitated by ELISA. The activity of enzymes and inhibitors was measured by functional assays. Treating chondrocytes with IL-1 induced the expression of MMPs and downregulated TIMP-1 but stimulated both the expression of PAs and PAI-1. Both drugs significantly reduced collagenase and proteoglycanase activities which was accompanied by inhibition of the expression of MMP-1 and MMP-3. The IL-1 decreased expression of TIMP-1 was further reduced by TA, which resulted in a significant loss of TIMP activity. No effects on TIMP activity or TIMP-1 biosynthesis were observed after treatment of chondrocytes with PSGAG. Both drugs inhibited the IL-1-induced mRNA expression of tPA, whereas expression of uPA was only mildly reduced by PSGAG, which also induced PAI-1 above IL-1 stimulated levels. As inhibition of collagenase activities and tPA expression by PSGAG occurred at physiological concentrations it might be of clinical relevance, indicating that PSGAG could help reducing cartilage degradation and has a strong anti-fibrinolytic potential. Due to their co-regulation of MMPs and TIMP(s) glucocorticoids should be carefully studied for their overall effect on extracellular matrix proteolysis.
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PMID:Effects of polysulfated glycosaminoglycan and triamcinolone acetonid on the production of proteinases and their inhibitors by IL-1alpha treated articular chondrocytes. 1212 42

The aim of this study was to determine the expression of proteinases and inhibitors from the matrix metalloproteinase (MMP) (MMPs 1, 2, 3, 9, tissue inhibitors of metalloproteinases (TIMPs) 1, 2) and plasminogen activator ((PA) urokinase (uPA), tissue type (tPA), uPAR, plasminogen activator inhibitors (PAIs) 1, 2) systems in colorectal cancer pathology by gelatin zymography, enzyme-linked immunosorbent assays (ELISAs) and quenched fluorescent substrate hydrolysis. The levels of all studied MMPs, uPA, uPAR, TIMP-1 and PAIs were significantly greater in tumour tissues than normal tissues. However, tPA and TIMP-2 were greater in normal colon (P<0.05, Mann-Whitney) e.g. PAI-1: tumour, median 14.9 (range 0.2-80.2) ng/mg total protein; normal, 2.1 (0.1-65.0). Tumour levels of several factors, in particular MMP-1 and PAI-1, correlated with pathology, i.e. Dukes' stage, differentiation, lymphatic or vascular invasion and tumour depth. The interactions between proteinase systems in colorectal cancer are complex and the balance between active proteinases and their inhibitors is important for extracellular matrix (ECM) degradation/remodelling at each stage of the metastatic cascade.
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PMID:The plasminogen activator and matrix metalloproteinase systems in colorectal cancer: relationship to tumour pathology. 1270 68

We investigated the effect of highly purified eicosapentaenoic acid ethyl ester (EPA-E) on blood coagulation abnormalities and dysfunction of vascular endothelial cells in spontaneously diabetic Otsuka Long-Evans Tokushima Fatty rats. The animals were treated with either EPA-E or lard at a daily dose of 0.3 g/kg/day for 52 weeks by gavage, and their coagulation/fibrinolytic parameters, platelet aggregation, and functions of the vascular endothelial cells were examined. EPA-E significantly improved coagulation-related parameters including prothrombin time, activated partial thromboplastin time, fibrinogen level, and activities of factor II, V, VII, VIII, IX, X, XI, and XII, and antithrombin III, and fibrinolysis-related parameters including plasminogen, tissue-type plasminogen activator, alpha(2)-plasmin inhibitor, and plasminogen activator inhibitor. It also suppressed ADP- or collagen-induced platelet aggregation and the cholesterol/phospholipid molar ratio in platelet membranes at a dose of 0.3 g/kg. In addition, it significantly increased the migration activity of vascular endothelial cells, and decreased the binding of vascular endothelial cells to vascular endothelial growth factor. In contrast, lard had no effect on hypercoagulation, hypofibrinolysis, and platelet hyperaggregation but significantly aggravated the dysfunction of vascular endothelial cells. These data demonstrate that EPA-E beneficially altered certain factors known to promote thrombosis and atherosclerosis in this animal model.
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PMID:Long-term administration of highly purified eicosapentaenoic acid ethyl ester improves blood coagulation abnormalities and dysfunction of vascular endothelial cells in Otsuka Long-Evans Tokushima fatty rats. 1461 17

Uncontrolled activation of matrix metalloproteinases (MMPs) can result in tissue injury and inflammation, yet little is known about the activation of MMPs during orthotopic liver transplantation (OLT). OLT is associated with increased fibrinolytic activity due to elevated plasmin generation. The serine-protease plasmin not only causes degradation of fibrin clots but is also thought, amongst others, to play a role in the activation of some matrix metalloproteinases. We therefore studied the evolution of MMP-2 and -9 plasma concentrations during OLT and the effect of serine-protease inhibition by aprotinin on the level and activation of these MMPs. In a group of 24 patients who participated in a randomized, double-blind, placebo-controlled study we determined serial MMP-2 and MMP-9 plasma levels during transplantation using ELISA (total MMP), activity assays (activatable MMP) and zymography. In addition, the MMP-inhibitors TIMP-1 and TIMP-2 were assessed by ELISA. The putative regulating factors tumor necrosis factor alpha (TNF-alpha) and tissue-type plasminogen activator (t-PA) were assessed as well. Patients were administered high-dose aprotinin, regular-dose aprotinin or placebo during surgery. Plasma TIMP-1, TIMP-2 and MMP-2 level gradually decreased during transplantation. Approximately two-thirds of total MMP-2 appeared to be in its activatable proMMP form. No release of MMP-2 from the graft could be detected. In contrast, plasma levels of MMP-9 increased sharply during the anhepatic and postreperfusion periods. Peak MMP-9 levels of about eight times above baseline were found at 30 minutes after reperfusion. Most MMP-9 appeared to be in its active/inhibitor-complexed form. No significant differences were observed between the three treatment groups. However, in patients with more severe ischemia/reperfusion (I/R) injury the MMP-9 concentration, particularly of the active/inhibitor-complexed form, remained high at 120 minutes postreperfusion compared to patients with no or mild I/R injury. The decrease in plasma levels of MMP-2, TIMP-1 and TIMP-2 during OLT occurred irrespective of the severity of the I/R injury. There was a significant correlation between MMP-9 and t-PA levels, but not with TNF-alpha. In conclusion, OLT is associated with a sharp increase of MMP-9 during the anhepatic and postreperfusion periods, which coincided with the changes in t-PA. MMP-2, TIMP-1 and TIMP-2 gradually decreased during OLT. The composition of these MMPs was not altered by the use of aprotinin, suggesting that serine-protease/plasmin-independent pathways are responsible for MMP regulation during OLT. In addition, only MMP-9 seems to be involved in I/R injury during human liver transplantation.
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PMID:Plasma MMP-2 and MMP-9 and their inhibitors TIMP-1 and TIMP-2 during human orthotopic liver transplantation. The effect of aprotinin and the relation to ischemia/reperfusion injury. 1498 26

The ras oncogenes are among those most frequently found in human cancers. Blocking Ras farnesylation is a promising strategy for arresting cancer growth. Ras activates several signaling pathways with key roles in cellular proliferation, invasion, metastasis and angiogenesis. Furthermore, proteolytic activities of matrix proteinases such as urokinase-type plasminogen activator (uPA) and matrix metalloproteinases (MMPs) are regulated by Ras isoforms. Thus, we investigated the effects of SCH-66336, a farnesyltransferase inhibitor, on secretion of components of the plasminogen activation system as well as on the gelatinases MMP-2 and MMP-9, which play pivotal roles in matrix remodeling. SCH-66336 up to 5 microM did not significantly alter the viability of prostate (PC-3) and renal (Caki-1) cancer cells incubated in serum-depleted medium. SCH-66336 partly inhibited the processing of H-Ras, while levels of mature N-Ras and K-Ras remained unaffected. Under these noncytotoxic conditions, uPA and tPA levels were lowered in culture medium but raised in cell lysates, suggesting inhibition of trafficking pathways. In contrast, SCH-66336 had no effect on uPAR expression or on secreted PAI-1 levels. As expected, the reduction of uPA and tPA activities by SCH-66336 inhibited the conversion of plasminogen to plasmin by about 25% in PC-3 cells. SCH-66336 also inhibited the levels of secreted pro-MMP-2 and pro-MMP-9 as well as the release of their inhibitors TIMP-1 and TIMP-2. SCH-66336 decreased both the adhesion and even more so the migration of PC-3 cells on gelatin. Thus, SCH-66336 inhibited farnesylation in both cancer cell types, and H-Ras functions should be reduced by the drug. In addition, the lower levels of secreted proteinases in the presence of SCH-66336 suggest that reduced matrix remodeling and cell migration should occur in treated tumors.
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PMID:Farnesyltransferase inhibitor SCH-66336 downregulates secretion of matrix proteinases and inhibits carcinoma cell migration. 1560 18

Left ventricular (LV) remodeling following myocardial infarction (MI) is a complex process involving extracellular matrix degradation and fibrosis. While early remodeling is beneficial, chronic remodeling leads to decompensated heart failure (HF). We assessed the hypothesis that activation of the plasminogen-MMP system is involved in the remodeling of the infarct scar and compared it to the remaining viable myocardium. MI was induced by coronary artery ligature in 42 male Wistar rats. Three months following surgery, animals were divided into compensated (n=26) or decompensated (n=16) groups and compared to sham-operated rats (n=17). Scar and remaining viable LV myocardium (LVM) were separately analyzed for MMP-2, -7, -9, urokinase type and tissue type plasminogen activator (uPA and tPA) mRNA levels by RT-PCR. Their protein or activity levels, plus those of plasminogen/plasmin, tissue inhibitor of metalloproteinase-1, -2, -4 (TIMP-1, -2, -4) and plasminogen activator inhibitor-1 (PAI-1) were analyzed in tissue conditioned media by Western blot, ELISA and/or zymography. MMP and plasmin proteolytic activities were increased in the scar as compared to paired LVM thus indicating that activation of plasminogen and pro-MMPs is a key event in scar tissue remodeling. MMP and plasminogen activators (uPA, tPA) mRNAs were increased accordingly. Furthermore, inhibitors of the proteolytic enzymes, TIMP-1 and PAI-1 were increased in the scars from failing hearts and LVM thus suggesting a dynamic interplay between proteolysis and its inhibitors. This study shows a high degree of activation of the MMP-plasminogen system and the balance with their inhibitors in the infarcted myocardium, and suggests that this activation participates more to the remodeling of the scar tissue than to the remaining myocardium.
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PMID:The plasminogen-MMP system is more activated in the scar than in viable myocardium 3 months post-MI in the rat. 1562 36

Left ventricular (LV) hypertrophy is a natural response of the heart to increased pressure loading, but accompanying fibrosis and dilatation may result in irreversible life-threatening heart failure. Matrix metalloproteinases (MMPs) have been invoked in various cardiac diseases, however, direct genetic evidence for a role of the plasminogen activator (PA) and MMP systems in pressure overload-induced LV hypertrophy and in heart failure is lacking. Therefore, the consequences of transverse aortic banding (TAB) were analyzed in mice lacking tissue-type PA (t-PA(-/-)), urokinase-type PA (u-PA(-/-)), or gelatinase-B (MMP-9(-/-)), and in wild-type (WT) mice after adenoviral gene transfer of the PA-inhibitor PAI-1 or the MMP-inhibitor TIMP-1. TAB elevated LV pressure comparably in all genotypes. In WT and t-PA(-/-) mice, cardiomyocyte hypertrophy was associated with myocardial fibrosis, LV dilatation and dysfunction, and pump failure after 7 weeks. In contrast, in u-PA(-/-) mice or in WT mice after PAI-1- and TIMP-1-gene transfer, cardiomyocyte hypertrophy was moderate and only minimally associated with cardiac fibrosis and LV dilatation, resulting in better preservation of pump function. Deficiency of MMP-9 had an intermediate effect. These findings suggest that the use of u-PA- or MMP-inhibitors might preserve cardiac pump function in LV pressure overloading.
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PMID:Loss or inhibition of uPA or MMP-9 attenuates LV remodeling and dysfunction after acute pressure overload in mice. 1563 96

The aim of this study was to assess the expression of several metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in exudative pleural effusions, and their relationship with inflammatory and fibrinolytic mediators in parapneumonic effusions. The study included 51 parapneumonic effusions (30 empyema or complicated parapneumonic, 21 noncomplicated parapneumonic), 28 tuberculous, 30 malignant and 30 transudates. Inflammatory markers (tumour necrosis factor-alpha, interleukin-8, polymorphonuclear elastase), fibrinolytic system variables (tissue plasminogen activator (PA), urokinase PA (u-PA), plasminogen activation inhibitor (PAI)-1, PAI-2), and several MMPs (MMP-1, MMP-2, MMP-8, MMP-9) and TIMPs (TIMP-1, TIMP-2) were determined by ELISA in plasma and pleural fluid. Elevated MMP-2 and TIMP-1 concentrations were observed in all the pleural fluid samples studied. The group of empyema or complicated parapneumonic effusions showed higher MMP-1, MMP-8 and MMP-9 concentrations than the remaining exudates. There was no correlation between MMP and TIMP levels in plasma and pleural fluid in this group of effusions. In parapneumonic effusions, MMP-1, MMP-8 and MMP-9 showed a positive correlation with the inflammatory markers and with u-PA and PAI-1. Moreover, there was a relationship between MMP-8 concentration in pleural fluid and pleural thickening at the end of treatment. In conclusion, elevated metalloproteinase-1, -8 and -9 expression was found in parapneumonic pleural effusions. These metalloproteinases could be implicated in the local inflammatory response existing in this group of effusions.
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PMID:Metalloproteinases and tissue inhibitors of metalloproteinases in exudative pleural effusions. 1564 Mar 30

The spontaneously hypertensive stroke-prone rat (SHR-SP) is an experimental model of malignant hypertension which lead to secondary alterations of the extracellular matrix. Our aim was to determine ACE-inhibitor related changes of proteases involved in the reconstruction of the extracellular matrix in the brain. Twelve SHR-SP rats were randomized into two groups. Each group was treated with either an antihypertensive dose of ramipril or placebo for 6 months. Brain tissue plasminogen activator (t-PA) and urokinase (u-PA) were quantified by using casein-dependent plasminogen zymography, matrix metalloproteinase (MMP)-2 and MMP-9, by MMP-zymography, and tissue inhibitor of MMP (TIMP)-1 and -2, by reverse zymography. The amounts of u-PA, t-PA, and MMPs were significantly reduced in animals treated with ACE inhibitor. Plasminogen zymography showed a 39% reduction of u-PA in the basal ganglia (p < 0.0001); t-PA expression was reduced by 26% in the cortex and by 33% in the basal ganglia (p < 0.0001). MMP-2 expression was reduced by 15% in the cortex (p < 0.05) and by 10% in the basal ganglia (p < 0.05); MMP-9 expression significantly decreased by 37% in the cortex and by 25% in the basal ganglia (p < 0.0001 each). No differences were observed in the amount of TIMP-1 or TIMP-2. These findings provide new insights into the biochemical mechanisms underlying extracellular matrix proliferation and its modulation by ACE inhibitors. Therapeutic alterations that influence the proteolytic systems might prove important in the prevention of extracellular matrix accumulation and secondary microvascular vessel wall changes.
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PMID:ACE inhibition reduces activity of the plasminogen/plasmin and MMP systems in the brain of spontaneous hypertensive stroke-prone rats. 1572 Dec 22

We have established the well-defined cycling, pseudo-pregnant and pregnant rhesus monkey models, and used these to analyze expression of the common molecules specifically related to angiogenesis, apoptosis or proteolysis, such as vascular endothelial growth factor (VEGF) and its receptors KDR, flt-1, flt-4 and flk-1, basic fibroblast growth factor (bFGF) and its receptors Flg, transforming growth factor-alpha and beta1 (TGF-a/beta1), and TGF-beta1 receptor type I (TbetaR-I) and type II (TbetaR-II), as well as steroidogenic acute regulatory protein (StAR), tissue type plasminogen activator/urokinase plasminogen activator/plasminogen activator inhibitor type 1 (tPA/uPA/PAI-1) and matrix matalloproteinase type 1, -3/tissue inhibitor matalloproteinase type 1, -2, -3 (MMP-1, -3/TIMP-1, -2, -3), Fas/FasL, BcL-2/Bax, in the corpus luteum (CL), in the functional layer of the endometrium and in the materno-fetal boundary of the implantation site. We have demonstrated that: expression of these molecules in the monkey CL, endometrium and materno-fetal boundary of the implantation site is correlated well with CL functional and vascular development and with the processes involved in the establishment of the implantation window as well as with the early stages of placentation. A coordinated increase in tPA and its inhibitor PAI-1 expression in the monkey and rat CL may be instrumental in initiating luteal regression in both species, and correlated well with the timing of the closure of the implantation window, whereas high uPA activity in the CL is important for the early formation of the CL and for maintaining its function which is closely correlated to the period of establishment of the implantation window. Apoptosis, proteolysis and angiogenesis occur in the CL and in the endometrium during the time of establishment of the implantation window, as well as in the materno-fetal boundary of the implantation site at the early stages of placentation. It seems that these processes occur in these tissues in a coordinated and time- and cell-dependent manner, and are reliant on each other. Based on these observations, we have designed experiments to test the actions of some related available compounds on mouse implantation, used alone or in combination. The preliminary data showed that the compounds which could effectively affect apoptosis, angiogenesis or proteolysis in the implantation site were capable of effectively inhibiting implantation by acting on the endometrium and/or on the CL. Furthermore, the combined use of these compounds produced an obvious additive effect on inhibiting implantation. This finding suggested this may be a good approach for developing an anti-implantation agent.
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PMID:Involvement of molecules related to angiogenesis, proteolysis and apoptosis in implantation in rhesus monkey and mouse. 1579 44


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