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1.
Cell Cycle ; 18(22): 3137-3146, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31550972

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible and the most common fatal interstitial lung disease, which is characterized by damaged alveolar structure, the massive proliferation of fibroblasts and deposition of extracellular matrix (ECM). While the pathogenesis of IPF remains unclear, it has been clearly established that the excessive proliferation of lung fibroblasts is the most direct cause of fibrogenesis. Numerous proliferating fibroblasts form fibrous foci and secrete a large amount of ECM to aggravate the process of pulmonary fibrosis. Tissue plasminogen activator (tPA) is a kind of serine protease, its main function is to activate zymogens into active enzymes involved in fibrinolysis. Our study found tPA functioned as a cytokine to promote the proliferation of lung fibroblasts through intracellular signaling events involving Erk1/2, p90RSK, GSK-3ß phosphorylation, and cyclinD1 induction. We also uncovered that tPA indirectly activated the Wnt/ß-catenin signaling pathway by regulating the GSK-3ß phosphorylation level. It's well-known that Wnt/ß-catenin signaling pathway plays an important role in the pathogenesis of pulmonary fibrosis, in which the accumulation of ß-catenin in the cytoplasm is an important signal of the activation of Wnt/ß-catenin signaling pathway. Our study unveiled that tPA can serve as a cytokine involved in Wnt/ß-catenin signaling pathway and be implicated in pulmonary fibrosis.


Assuntos
Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar Idiopática/metabolismo , Ativador de Plasminogênio Tecidual/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclina D1/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/metabolismo
2.
Chembiochem ; 20(1): 46-50, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30225958

RESUMO

Urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) are two serine proteases that contribute to initiating fibrinolysis by activating plasminogen. uPA is also an important tumour-associated protease due to its role in extracellular matrix remodelling. Overexpression of uPA has been identified in several different cancers and uPA inhibition has been reported as a promising therapeutic strategy. Although several peptide-based uPA inhibitors have been developed, the extent to which uPA tolerates different tetrapeptide sequences that span the P1-P4 positions remains to be thoroughly explored. In this study, we screened a sequence-defined peptide aldehyde library against uPA and tPA. Preferred sequences from the library screen yielded potent inhibitors for uPA, led by Ac-GTAR-H (Ki =18 nm), but not for tPA. Additionally, synthetic peptide substrates corresponding to preferred inhibitor sequences were cleaved with high catalytic efficiency by uPA but not by tPA. These findings provide new insights into the binding specificity of uPA and tPA and the relative activity of tetrapeptide inhibitors and substrates against these enzymes.


Assuntos
Aldeídos/química , Inibidores Enzimáticos/química , Peptídeos/química , Ativador de Plasminogênio Tecidual/química , Ativador de Plasminogênio Tipo Uroquinase/química , Aldeídos/síntese química , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Humanos , Biblioteca de Peptídeos , Peptídeos/síntese química , Especificidade por Substrato , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores
3.
J Cell Physiol ; 234(4): 3948-3960, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30132879

RESUMO

The invasion of glioblastoma is a complex process based on the interactions of tumor cells and the extracellular matrix. Tumors that are engineered using biomaterials are more physiologically relevant than a two-dimensional (2D) cell culture system. Matrix metalloproteinases and the plasminogen activator generated by tumor cells regulate a tumor's invasive behavior. In this study, microtumors were fabricated by encapsulating U87 glioma cells in Type I collagen and then glioma cell migration in the collagen hydrogels was investigated. Crosslinking of collagen with 8S-StarPEG increased the hydrogel viscosity and reduced the tumor cell migration speed in the hydrogels. The higher migration speed corresponded to the increased gene expression of MMP-2, MMP-9, urokinase plasminogen activator (uPA), and tissue plasminogen activator (tPA) in glioma cells grown in non-crosslinked collagen hydrogels. Inhibitors of these molecules hindered U87 and A172 cell migration in collagen hydrogels. Aprotinin and tranexamic acid did not inhibit U87 and A172 migration on the culture dish. This study demonstrated the differential effect of pharmacologic molecules on tumor cell motility in either a 2D or three-dimensional culture environment.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Colágeno/metabolismo , Glioblastoma/tratamento farmacológico , Inibidores de Proteases/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Hidrogéis , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Invasividade Neoplásica , Transdução de Sinais , Estresse Mecânico , Fatores de Tempo , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/metabolismo , Viscosidade
4.
Sci Rep ; 6: 18769, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26732982

RESUMO

Neuroserpin (NS) is a serpin inhibitor of tissue plasminogen activator (tPA) in the brain. The polymerisation of NS pathologic mutants is responsible for a genetic dementia known as familial encephalopathy with neuroserpin inclusion bodies (FENIB). So far, a pharmacological treatment of FENIB, i.e. an inhibitor of NS polymerisation, remains an unmet challenge. Here, we present a biophysical characterisation of the effects caused by embelin (EMB a small natural compound) on NS conformers and NS polymerisation. EMB destabilises all known NS conformers, specifically binding to NS molecules with a 1:1 NS:EMB molar ratio without unfolding the NS fold. In particular, NS polymers disaggregate in the presence of EMB, and their formation is prevented. The NS/EMB complex does not inhibit tPA proteolytic activity. Both effects are pharmacologically relevant: firstly by inhibiting the NS polymerisation associated to FENIB, and secondly by potentially antagonizing metastatic processes facilitated by NS activity in the brain.


Assuntos
Benzoquinonas/metabolismo , Neuropeptídeos/metabolismo , Multimerização Proteica , Serpinas/metabolismo , Benzoquinonas/química , Dicroísmo Circular , Humanos , Cinética , Ligantes , Espectrometria de Massas/métodos , Neuropeptídeos/química , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Serpinas/química , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Neuroserpina
5.
Crit Care Med ; 44(6): e383-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26646461

RESUMO

INTERVENTIONS: Helium has been shown to provide neuroprotection in mechanical model of acute ischemic stroke by inducing hypothermia, a condition shown by itself to reduce the thrombolytic and proteolytic properties of tissue plasminogen activator. However, whether or not helium interacts with the thrombolytic drug tissue plasminogen activator, the only approved therapy of acute ischemic stroke still remains unknown. This point is not trivial since previous data have shown the critical importance of the time at which the neuroprotective noble gases xenon and argon should be administered, during or after ischemia, in order not to block tissue plasminogen activator-induced thrombolysis and to obtain neuroprotection and inhibition of tissue plasminogen activator-induced brain hemorrhages. MEASUREMENTS AND MAIN RESULTS: We show that helium of 25-75 vol% inhibits in a concentration-dependent fashion the catalytic and thrombolytic activity of tissue plasminogen activator in vitro and ex vivo. In vivo, in rats subjected to thromboembolic brain ischemia, we found that intraischemic helium at 75 vol% inhibits tissue plasminogen activator-induced thrombolysis and subsequent reduction of ischemic brain damage and that postischemic helium at 75 vol% reduces ischemic brain damage and brain hemorrhages. CONCLUSIONS: In a clinical perspective for the treatment of acute ischemic stroke, these data suggest that helium 1) should not be administered before or together with tissue plasminogen activator therapy due to the risk of inhibiting the benefit of tissue plasminogen activator-induced thrombolysis; and 2) could be an efficient neuroprotective agent if given after tissue plasminogen activator-induced reperfusion.


Assuntos
Antifibrinolíticos/administração & dosagem , Hélio/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Tromboembolia/tratamento farmacológico , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/uso terapêutico , Animais , Antifibrinolíticos/farmacologia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Hélio/farmacologia , Hemorragias Intracranianas/tratamento farmacológico , Masculino , Ratos , Acidente Vascular Cerebral/etiologia , Tromboembolia/complicações
6.
Blood Coagul Fibrinolysis ; 27(5): 511-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26575490

RESUMO

In addition to degrading fibrinogen as a source of consumptive coagulopathy, rattlesnake venom has also been demonstrated to enhance fibrinolysis and degrade alpha-2-antiplasmin. The goals of this investigation was to characterize the kinetic fibrinolytic profile of Crotalus atrox venom in the absence and presence of tissue-type plasminogen activator (tPA), and to also ascertain if iron and carbon monoxide (CO, a positive modulator of alpha-2-antiplasmin) could attenuate venom-enhanced fibrinolysis. Utilizing thrombelastographic methods, the coagulation and fibrinolytic kinetic profiles of human plasma exposed to C. atrox venom (0-2 µg/ml) were determined in the absence or presence of tPA (0-100 IU/ml). Then, either separately or in combination, plasma was exposed to iron (ferric chloride, 10 µmol/l) or CO (carbon monoxide-releasing molecule-2, 100 µmol/l) prior to incubation with venom; the plasma sample was subsequently subjected to thrombelastographic analysis with addition of tPA. Venom exposure in the absence of tPA did not result in detectable fibrinolysis. In the presence of tPA, venom markedly enhanced fibrinolysis. Iron and CO, markedly attenuated venom enhancement of fibrinolysis. C. atrox venom enhances tPA-mediated fibrinolysis, and interventions that enhance/protect alpha-2-antiplasmin activity significantly attenuate venom-enhanced fibrinolysis. Future preclinical investigation is required to determine if iron and CO can attenuate venom-mediated degradation of alpha-2-antiplasmin-dependent fibrinolytic resistance.


Assuntos
Monóxido de Carbono/farmacologia , Cloretos/farmacologia , Venenos de Crotalídeos/antagonistas & inibidores , Compostos Férricos/farmacologia , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/farmacologia , Hemostáticos/farmacologia , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Animais , Monóxido de Carbono/química , Venenos de Crotalídeos/farmacologia , Crotalus/metabolismo , Tempo de Lise do Coágulo de Fibrina , Fibrinogênio/metabolismo , Humanos , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Tromboelastografia , Ativador de Plasminogênio Tecidual/farmacologia , alfa 2-Antiplasmina/metabolismo , alfa 2-Antiplasmina/farmacologia
7.
Int J Mol Sci ; 16(11): 27550-60, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26593907

RESUMO

Tissue plasminogen activator (tPA) mediates a number of processes that are pivotal for synaptogenesis and remodeling of synapses, including proteolysis of the brain extracellular matrix, degradation of adhesion molecules, activation of neurotrophins, and activation of the N-methyl-d-aspartate receptor. Abnormalities in these processes have been consistently described in psychotic disorders. In this paper, we review the physiological roles of tPA, focusing on conditions characterized by low tPA activity, which are prevalent in schizophrenia. We then describe how tPA activity is influenced by lifestyle interventions and nutritional supplements that may ameliorate psychotic symptoms. Next, we analyze the role of tPA in the mechanism of action of hormones and medications effective in mitigating psychotic symptoms, such as pregnenolone, estrogen, oxytocin, dopamine D3 receptor antagonists, retinoic acid, valproic acid, cannabidiol, sodium nitroprusside, N-acetyl cysteine, and warfarin. We also review evidence that tPA participates in the mechanism by which electroconvulsive therapy and cigarette smoking may reduce psychotic symptoms.


Assuntos
Fenótipo , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Antipsicóticos/uso terapêutico , Encéfalo/metabolismo , Suplementos Nutricionais , Eletroconvulsoterapia , Hormônios/metabolismo , Humanos , Estilo de Vida , Neuropeptídeos/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ligação Proteica , Transtornos Psicóticos/terapia , Esquizofrenia/diagnóstico , Esquizofrenia/dietoterapia , Esquizofrenia/metabolismo , Esquizofrenia/terapia , Serpinas/metabolismo , Fumar , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Neuroserpina
8.
Eur J Anaesthesiol ; 32(12): 844-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26258658

RESUMO

BACKGROUND: Although recent studies have assessed tranexamic acid (TXA) pharmacokinetics in different subgroups, the effective concentration of TXA required to completely inhibit fibrinolysis remains to be determined. OBJECTIVE: An in-vitro determination of the effective TXA concentration needed for 95% inhibition (EC95) of tissue-type plasminogen activator (t-PA) activated fibrinolysis, using an experimental model designed for thromboelastometry (ROTEM). DESIGN: A prospective interventional study. SETTING: Department of Anaesthesiology, Queen Fabiola Children's University Hospital and Laboratory of Haematology and Haemostasis, Brugmann University Hospital. Patients were enrolled between June 2013 and October 2014. PATIENTS AND VOLUNTEERS: Twenty children, aged between 1 and 10 years, undergoing elective cardiac catheterisation were included (10 with cyanotic and 10 with noncyanotic diseases). Exclusion criteria were child requiring a procedure in a moribund state. Ten adult volunteers were also included as controls. INTERVENTION: Citrated whole blood samples were obtained from children and volunteers. MAIN OUTCOMES MEASURES: The extrinsic coagulation pathway was activated by tissue factor using the EXTEM test on ROTEM. The degree of lysis measured 30 min (LI30) after the clotting time (CT), and clot amplitudes measured at different times were recorded at baseline, after addition of 1535 units t-PA ml(-1), and following the addition of increasing TXA concentrations in t-PA activated samples. RESULTS: The concentration-effect analysis performed with lysis index after 30 min (LI30) allowed the determination of TXA efficacy concentration 50% (EC50), and calculation of the EC95, which was significantly lower in cardiac surgery children than in adults [8.6 µg ml(-1); 95% confidence interval (95% CI) 6.9 to 14.9 versus 11.3 µg ml(-1); 95% CI 10.6 to 12.9, P < 0.001]. CONCLUSION: In this in-vitro study, we observed that the EC95 TXA concentration that completely inhibited t-PA induced hyperfibrinolysis in children with congenital heart was significantly lower than the concentration required in healthy adult volunteers. Further studies are needed to confirm that this plasma concentration can effectively inhibit fibrinolysis activation in children undergoing cardiac surgery.


Assuntos
Antifibrinolíticos/uso terapêutico , Fibrinólise/efeitos dos fármacos , Cardiopatias Congênitas/tratamento farmacológico , Cardiopatias Congênitas/cirurgia , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ácido Tranexâmico/uso terapêutico , Adulto , Antifibrinolíticos/farmacologia , Criança , Pré-Escolar , Feminino , Fibrinólise/fisiologia , Cardiopatias Congênitas/sangue , Humanos , Lactente , Masculino , Estudos Prospectivos , Ativador de Plasminogênio Tecidual/sangue , Ácido Tranexâmico/farmacologia , Resultado do Tratamento
9.
ScientificWorldJournal ; 2014: 858293, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25386620

RESUMO

Plasminogen activator inhibitor-1 (PAI-1) is the main inhibitor of plasminogen activators, such as tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA), and a major regulator of the fibrinolytic system. PAI-1 plays a pivotal role in acute thrombotic events such as deep vein thrombosis (DVT) and myocardial infarction (MI). The biological effects of PAI-1 extend far beyond thrombosis including its critical role in fibrotic disorders, atherosclerosis, renal and pulmonary fibrosis, type-2 diabetes, and cancer. The conversion of PAI-1 from the active to the latent conformation appears to be unique among serpins in that it occurs spontaneously at a relatively rapid rate. Latency transition is believed to represent a regulatory mechanism, reducing the risk of thrombosis from a prolonged antifibrinolytic action of PAI-1. Thus, relying solely on plasma concentrations of PAI-1 without assessing its function may be misleading in interpreting the role of PAI-1 in many complex diseases. Environmental conditions, interaction with other proteins, mutations, and glycosylation are the main factors that have a significant impact on the stability of the PAI-1 structure. This review provides an overview on the current knowledge on PAI-1 especially importance of PAI-1 level and stability and highlights the potential use of PAI-1 inhibitors for treating cardiovascular disease.


Assuntos
Infarto do Miocárdio/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Trombose Venosa/genética , Humanos , Rim/metabolismo , Rim/patologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/patologia , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 1 de Ativador de Plasminogênio/uso terapêutico , Estabilidade Proteica , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/genética , Trombose Venosa/sangue , Trombose Venosa/patologia
10.
Antimicrob Agents Chemother ; 57(9): 4114-27, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23774438

RESUMO

Lethal viral infections produce widespread inflammation with vascular leak, clotting, and bleeding (disseminated intravascular coagulation [DIC]), organ failure, and high mortality. Serine proteases in clot-forming (thrombotic) and clot-dissolving (thrombolytic) cascades are activated by an inflammatory cytokine storm and also can induce systemic inflammation with loss of normal serine protease inhibitor (serpin) regulation. Myxomavirus secretes a potent anti-inflammatory serpin, Serp-1, that inhibits clotting factor X (fX) and thrombolytic tissue- and urokinase-type plasminogen activators (tPA and uPA) with anti-inflammatory activity in multiple animal models. Purified serpin significantly improved survival in a murine gammaherpesvirus 68 (MHV68) infection in gamma interferon receptor (IFN-γR) knockout mice, a model for lethal inflammatory vasculitis. Treatment of MHV68-infected mice with neuroserpin, a mammalian serpin that inhibits only tPA and uPA, was ineffective. Serp-1 reduced virus load, lung hemorrhage, and aortic, lung, and colon inflammation in MHV68-infected mice and also reduced virus load. Neuroserpin suppressed a wide range of immune spleen cell responses after MHV68 infection, while Serp-1 selectively increased CD11c(+) splenocytes (macrophage and dendritic cells) and reduced CD11b(+) tissue macrophages. Serp-1 altered gene expression for coagulation and inflammatory responses, whereas neuroserpin did not. Serp-1 treatment was assessed in a second viral infection, mouse-adapted Zaire ebolavirus in wild-type BALB/c mice, with improved survival and reduced tissue necrosis. In summary, treatment with this unique myxomavirus-derived serpin suppresses systemic serine protease and innate immune responses caused by unrelated lethal viral infections (both RNA and DNA viruses), providing a potential new therapeutic approach for treatment of lethal viral sepsis.


Assuntos
Hemorragia/tratamento farmacológico , Doença pelo Vírus Ebola/tratamento farmacológico , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/mortalidade , Proteínas de Membrana/farmacologia , Myxoma virus/química , Animais , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Modelos Animais de Doenças , Ebolavirus , Fator X/antagonistas & inibidores , Fator X/metabolismo , Gammaherpesvirinae , Hemorragia/mortalidade , Hemorragia/patologia , Hemorragia/virologia , Doença pelo Vírus Ebola/mortalidade , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/virologia , Infecções por Herpesviridae/patologia , Infecções por Herpesviridae/virologia , Inflamação/tratamento farmacológico , Inflamação/mortalidade , Inflamação/patologia , Inflamação/virologia , Interferon gama/deficiência , Interferon gama/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Proteínas de Membrana/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Myxoma virus/fisiologia , Neuropeptídeos/farmacologia , Serpinas/farmacologia , Análise de Sobrevida , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Vasculite/tratamento farmacológico , Vasculite/mortalidade , Vasculite/patologia , Vasculite/virologia , Neuroserpina
11.
Int J Mol Med ; 31(3): 503-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23314920

RESUMO

Plasminogen activator inhibitor type-1 (PAI-1) inhibits tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA), which convert plasminogen to plasmin, a strong proteolytic enzyme. Thus, PAI-1 is a primary and negative regulator of plasmin-driven proteolysis. In addition to its main role as an inhibitor of fibrinolysis, PAI­1 has been implicated as a mediator in other processes, including fibrosis, rheumatoid arthritis, atherosclerosis, tumor angiogenesis and bacterial infections. It also significantly modulates cellular adhesion or migration, wound healing, angiogenesis and tumor cell metastasis. However, in the present study, we have reviewed the literature in relation to different kidney diseases where PAI-1 regulates fibrinolysis and acts independently of proteolysis. PAI-1 is normally produced in trace amounts in healthy kidneys but is synthesized in a wide variety of both acute and chronic diseased kidneys. We reviewed the role of PAI-1 in diabetic kidney nephropathy, chronic kidney disease, hemodialysis, peritoneal dialysis and in kidney transplantation. Increased PAI-1 expression results in accumulation of extracellular matrix (ECM) leading to numerous kidney diseases. Predisposition to some diseases is due to the genetic role of PAI-1 in their development. A number of studies demonstrated that the inhibition of PAI-1 activity or therapy with a mutant PAI-1 increases matrix turnover and reduces glomerulosclerosis by competing with endogenous PAI-1. This strongly suggests that PAI-1 is a valid target in the treatment of fibrotic renal disease. However, net proteolytic activity depends on the delicate balance between its negative regulation by PAI-1 and activation by uPA and tPA. Also, plasmin activated by its inhibitors upregulates activity of other enzymes. Thus, assessment of prognosis for the diseased kidney should include a variety of proteolysis regulators and enzymes.


Assuntos
Matriz Extracelular/metabolismo , Rim/patologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Animais , Nefropatias Diabéticas/metabolismo , Fibrinólise , Humanos , Transplante de Rim , Diálise Peritoneal , Proteólise , Diálise Renal , Insuficiência Renal Crônica/metabolismo , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores
12.
J Enzyme Inhib Med Chem ; 28(3): 639-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22299583

RESUMO

Eight peptides of the general H-D-Ser-AA-Arg-OH formula, where AA = phenylglycine, phenylalanine, homophenylalanine, cyclohexylglycine, cyclohexylalanine, homocyclohexylalanine, α-methylphenylalanine and 1-aminocyclohexyl carboxylic acid were obtained and tested for their effect on the amidolytic activities of urokinase, thrombin, trypsin, plasmin, t-PA and kallikrein. We tested the hemolytic activity of the peptides against porcine erythrocytes and the antitumor activity against the human breast cancer cells, standard MCF-7 and estrogen-independent MDA-MB-231. The most active compounds were H-D-Ser-Chg-Arg-OH towards thrombin and H-D-Ser-Phg-Arg-OH towards plasmin with K(i) value 5.02 µM and 5.7 µM, respectively.


Assuntos
Oligopeptídeos/química , Oligopeptídeos/farmacologia , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Eritrócitos/efeitos dos fármacos , Feminino , Fibrinolisina/antagonistas & inibidores , Humanos , Calicreínas/antagonistas & inibidores , Suínos , Trombina/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Inibidores da Tripsina/química , Inibidores da Tripsina/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores
13.
Brain ; 135(Pt 11): 3282-97, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23169919

RESUMO

Only a minority of stroke patients receive thrombolytic therapy. Therefore, new therapeutic strategies focusing on neuroprotection are under review, among which, inhibition of the proteasome is attractive, as it affects multiple cellular pathways. As proteasome inhibitors like bortezomib have severe side effects, we applied the novel proteasome inhibitor BSc2118, which is putatively better tolerated, and analysed its therapeutic potential in a mouse model of cerebral ischaemia. Stroke was induced in male C57BL/6 mice using the intraluminal middle cerebral artery occlusion model. BSc2118 was intrastriatally injected 12 h post-stroke in mice that had received normal saline or recombinant tissue-plasminogen activator injections during early reperfusion. Brain injury, behavioural tests, western blotting, MMP9 zymography and analysis of angioneurogenesis were performed for up to 3 months post-stroke. Single injections of BSc2118 induced long-term neuroprotection, reduced functional impairment, stabilized blood-brain barrier through decreased MMP9 activity and enhanced angioneurogenesis when given no later than 12 h post-stroke. On the contrary, recombinant tissue-plasminogen activator enhanced brain injury, which was reversed by BSc2118. Protein expression of the transcription factor HIF1A was significantly increased in saline-treated and recombinant tissue-plasminogen activator-treated mice after BSc2118 application. In contrast, knock-down of HIF1A using small interfering RNA constructs or application of the HIF1A inhibitor YC1 (now known as RNA-binding motif, single-stranded-interacting protein 1 (RBMS1)) reversed BSc2118-induced neuroprotection. Noteworthy, loss of neuroprotection after combined treatment with BSc2118 and YC1 in recombinant tissue-plasminogen activator-treated animals was in the same order as in saline-treated mice, i.e. reduction of recombinant tissue-plasminogen activator toxicity through BSc2118 did not solely depend on HIF1A. Thus, the proteasome inhibitor BSc2118 is a promising new candidate for stroke therapy, which may in addition alleviate recombinant tissue-plasminogen activator-induced brain toxicity.


Assuntos
Indutores da Angiogênese/farmacologia , Isquemia Encefálica/tratamento farmacológico , Butanos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fármacos Neuroprotetores/farmacologia , Oligopeptídeos/farmacologia , Inibidores de Proteassoma/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Butanos/administração & dosagem , Butanos/antagonistas & inibidores , Butanos/uso terapêutico , Butanos/toxicidade , Modelos Animais de Doenças , Interações Medicamentosas , Técnicas de Silenciamento de Genes , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microinjeções , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Oligopeptídeos/administração & dosagem , Oligopeptídeos/antagonistas & inibidores , Oligopeptídeos/uso terapêutico , Oligopeptídeos/toxicidade , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Recuperação de Função Fisiológica/efeitos dos fármacos , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/efeitos adversos , Ativador de Plasminogênio Tecidual/antagonistas & inibidores
15.
Biol. Res ; 45(4): 357-362, 2012. ilus
Artigo em Inglês | LILACS | ID: lil-668686

RESUMO

Hypoxia-ischemia (HI) occurring in immature brains stimulates the expression of tissue-type plasminogen activator (tPA). Neuroserpin is a selected inhibitor of tPA in the central nerves system. However, the role that neuroserpin plays and the possible mechanisms involved during neonatal HI are poorly defined. In this study, an oxygen-glucose deprivation and reoxygenation (OGD/R) model was generated with cultured rat cortical neurons mimicking neonatal HI injury ex vivo, and an acute neuronal excitatory injury was induced by exposure to a high concentration of N-methyl-D-aspartic acid (NMDA). Cells received either neuroserpin or MK-801, an antagonist of the NMDA receptor, during OGD/R, and were incubated with or without neuroserpin after NMDA exposure. Cell viability and morphology were detected by a Cell Counting Kit-8 and immunohistochemical staining, respectively. TPA expression and activity were also assessed. We found that MK-801 alleviated injuries induced by OGD/R, suggesting an excitatory damage involvement. Neuroserpin provided a dose-dependent neuroprotective effect in both OGD/R and acute excitatory injuries by inhibiting the activity of tPA, without affecting neuronal tPA expression. Neuroserpin protected neurons against OGD/R even after a delayed administration of 3h. Collectively, our data indicate that neuroserpin protects neurons against OGD/R. mainly by inhibiting tPA-mediated acute neuronal excitotoxicity.


Assuntos
Animais , Feminino , Gravidez , Ratos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Neuropeptídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Serpinas/uso terapêutico , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Animais Recém-Nascidos , Sobrevivência Celular , Maleato de Dizocilpina/farmacologia , Hipóxia-Isquemia Encefálica/etiologia , Imuno-Histoquímica , N-Metilaspartato , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Adv Med Sci ; 56(2): 323-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22037173

RESUMO

PURPOSE: The aim of this work was to study the effect of the synthetic antifibrinolytics: ε-aminocaproic acid (EACA), tranexamic acid (AMCHA) and ε-aminocaproyl-S-benzyl-L-cysteine (H-EACA-S-Bzl-L-Cys-OH) on the fibrinolytic activity of saliva in order to obtain new data on the activity of saliva tissue plasminogen activator (t-PA). MATERIAL AND METHODS: Saliva samples were obtained from healthy volunteers. Saliva, precipitate and supernatant were tested 1hr, 4 hrs and 6hrs after collection. The effect of the synthetic antifibrinolytics was examined with the use of the clot lysis time determination. RESULTS: All examined compounds inhibited the fibrinolytic activity of saliva 1hr after collection. H-EACA-S-Bzl-L-Cys-OH was the most active inhibitor. After 6 hours in room temperature only this compound showed a certain possibility to prolong the clot lysis time. CONCLUSIONS: The obtained results may indicate the possibility of the difference in specificity between the activities of t-PA of saliva and recombinant tissue plasminogen activator activities. It may explain the unexpected high inhibitory activity of H-EACA-S-Bzl-L-Cys-OH in our study.


Assuntos
Aminocaproatos , Cisteína/análogos & derivados , Saliva/efeitos dos fármacos , Ativador de Plasminogênio Tecidual/metabolismo , Ácido Aminocaproico/farmacologia , Animais , Antifibrinolíticos/farmacologia , Coagulação Sanguínea , Bovinos , Cisteína/farmacologia , Fibrinogênio/metabolismo , Fibrinólise , Hemorragia , Humanos , Modelos Biológicos , Peptídeos/química , Saliva/metabolismo , Fatores de Tempo , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ácido Tranexâmico/farmacologia
17.
Neurol Res ; 33(7): 726-33, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21756552

RESUMO

OBJECTIVE: N-methyl-D-aspartate (NMDA)-induced pial artery dilation (PAD) is reversed to vasoconstriction after fluid percussion brain injury (FPI). Tissue type plasminogen activator (tPA) is up-regulated and the tPA antagonist, EEIIMD, prevents impaired NMDA PAD after FPI. Mitogen-activated protein kinase (MAPK), a family of at least three kinases, ERK, p38, and JNK, is also up-regulated after traumatic brain injury (TBI). We hypothesize that tPA impairs NMDA-induced cerebrovasodilation after FPI in a MAPK isoform-dependent mechanism. METHODS: Lateral FPI was induced in newborn pigs. The closed cranial window technique was used to measure pial artery diameter and to collect cerebrospinal fluid (CSF). ERK, p38, and JNK MAPK concentrations in CSF were quantified by ELISA. RESULTS: CSF JNK MAPK was increased by FPI, increased further by tPA, but blocked by JNK antagonists SP600125 and D-JNKI1. FPI modestly increased p38 and ERK isoforms of MAPK. NMDA-induced PAD was reversed to vasoconstriction after FPI, whereas dilator responses to papaverine were unchanged. tPA, in post-FPI CSF concentration, potentiated NMDA-induced vasoconstriction while papaverine dilation was unchanged. SP 600125 and D-JNKI1, blocked NMDA-induced vasoconstriction and fully restored PAD. The ERK antagonist U 0126 partially restored NMDA-induced PAD, while the p38 inhibitor SB203580 aggravated NMDA-induced vasoconstriction observed in the presence of tPA after FPI. DISCUSSION: These data indicate that tPA contributes to impairment of NMDA-mediated cerebrovasodilation after FPI through JNK, while p38 may be protective. These data suggest that inhibition of the endogenous plasminogen activator system and JNK may improve cerebral hemodynamic outcome post-TBI.


Assuntos
Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Proteínas Quinases JNK Ativadas por Mitógeno/líquido cefalorraquidiano , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , N-Metilaspartato/farmacologia , Vasodilatação/fisiologia , Animais , Animais Recém-Nascidos , Antracenos/farmacologia , Butadienos/farmacologia , Interações Medicamentosas/fisiologia , Feminino , Imidazóis/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/líquido cefalorraquidiano , N-Metilaspartato/agonistas , N-Metilaspartato/antagonistas & inibidores , Nitrilas/farmacologia , Oligopeptídeos/farmacologia , Papaverina/farmacologia , Peptídeos/farmacologia , Pia-Máter/irrigação sanguínea , Piridinas/farmacologia , Suínos , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
18.
Microvasc Res ; 82(1): 6-17, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21406197

RESUMO

Both the antiangiogenic and antitumoral activity of shark cartilage extracts (SCE) have been demonstrated in animal models and clinical trials. Studies reported that SCE induces the expression of tissue plasminogen activator gene (PLAT) in endothelial cells and increases the activity of the protein (t-PA) in vitro. The aim of this study was to demonstrate the crucial role of t-PA induction in the antiangiogenic and antitumor activity of SCE in experimental glioma. This study showed antiangiogenic and antitumoral effects of SCE in three mice glioma models (C6, HGD and GL26). Histological examination suggested perivascular proteolysis and edema as well as important intratumoral necrosis, which artefactually increased the tumor volume at high doses. Thus, the antiangiogenic effect of SCE correlated with the presence of t-PA and angiostatin in degenerating vessels. Functional in vivo experiments were conducted to modulate the plasminogen pathway. No antiangiogenic effect was observed on tumors overexpressing the plasminogen activator inhibitor-1 (PAI-1). Moreover, therapeutical effects were neutralized in mice that were cotreated with ε-aminocaproic acid (EACA, 120 mg/kg p.o.), an inhibitor that blocks the high-affinity lysine binding sites of both plasminogen and plasmin. In contrast, cotreatment with N-acetylcysteine (NAC, 7,5mg/kg i.p.), a sulfhydril donor that reduces plasmin into angiostatin or other antiangiogenic fragments, increased the benefit of SCE on mice survival. In subcutaneous models, NAC prevented the increase in tumor volume caused by high doses of cartilage extract. In conclusion, this study indicates that induction of t-PA by shark cartilage extract plays an essential role in its antiangiogenic activity, but that control of excessive proteolysis by a plasmin reductor could prevent edema and uncover the full benefit of shark cartilage extract in the treatment of intracranial tumors.


Assuntos
Fibrinólise/efeitos dos fármacos , Glioma/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Extratos de Tecidos/farmacologia , Extratos de Tecidos/uso terapêutico , Acetilcisteína/metabolismo , Acetilcisteína/farmacologia , Ácido Aminocaproico/farmacologia , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Angiostatinas/metabolismo , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Núcleo Caudado/patologia , Linhagem Celular Tumoral , Fibrinolisina/antagonistas & inibidores , Fibrinolisina/farmacologia , Glioma/irrigação sanguínea , Glioma/metabolismo , Glioma/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neovascularização Patológica/patologia , Plasminogênio/antagonistas & inibidores , Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Ratos , Análise de Sobrevida , Extratos de Tecidos/administração & dosagem , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/metabolismo , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Stroke ; 42(4): 1097-104, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21350203

RESUMO

BACKGROUND AND PURPOSE: Thrombolysis therapy using tissue-type plasminogen activator (t-PA) is occasionally accompanied by harmful outcomes, including intracerebral hemorrhage. We have reported that Stachybotrys microspora triprenyl phenol-7 (SMTP-7), a candidate thrombolytic drug, has excellent therapeutic effect on cerebral infarction in embolic stroke model in mice; however, little is known regarding whether this agent influences cerebrovascular inflammation following thrombolytic reperfusion. The current study aimed to compare the effects of recombinant t-PA (rt-PA) and SMTP-7 on cerebrovascular inflammation. METHODS: The impact of rt-PA- and SMTP-7-induced thrombolytic reperfusion on leukocyte dynamics was investigated in a photochemically induced thrombotic middle cerebral artery occlusion (tMCAo) model in mice. RESULTS: Both rt-PA and SMTP-7 administration in tMCAo mice (each 10 mg/kg) resulted in thrombolytic reperfusion. The SMTP-7-administered mice showed relatively mild rolling and attachment of leukocytes to the vascular wall in the middle cerebral vein, with weak peroxynitrite reactions and proinflammatory gene expression (IL-1ß, TNF-α, ICAM-1, and VCAM-1); thus, a small infarct volume compared with rt-PA-administered mice. In vitro study suggested that rt-PA at 20 µg/mL, but not SMTP-7 at a similar concentration, promotes cytokine-induced reactive oxygen species generation in cultured endothelial cells; moreover, SMTP-7 suppressed cytokine-induced VCAM-1 induction in the cells and leukocyte/ endothelial cell adhesions. CONCLUSIONS: Relatively mild cerebrovascular inflammation and cerebral infarction in the SMTP-7 mice, compared with in rt-PA mice, is thought to be caused at least in part by direct antioxidative actions of SMTP-7 in ECs.


Assuntos
Benzopiranos/toxicidade , Infarto da Artéria Cerebral Média/patologia , Embolia Intracraniana/patologia , Pirrolidinonas/toxicidade , Traumatismo por Reperfusão/patologia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/toxicidade , Animais , Benzopiranos/antagonistas & inibidores , Linhagem Celular Tumoral , Células Cultivadas , Modelos Animais de Doenças , Humanos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/etiologia , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Inflamação/etiologia , Embolia Intracraniana/tratamento farmacológico , Embolia Intracraniana/etiologia , Lasers , Masculino , Camundongos , Pirrolidinonas/antagonistas & inibidores , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/etiologia , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/antagonistas & inibidores
20.
Mol Biol Rep ; 38(4): 2541-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21082259

RESUMO

A case-control association study on 229 Myocardial Infarction (MI) patients and 217 healthy controls was carried out to determine the role of tissue-plasminogen activator (t-PA) (Alu-repeat insertion (I)/deletion (D)) and plasminogen activator inhibitor (PAI-1) (4G/5G insertion/deletion) polymorphisms with MI in the Pakistani population. In MI patients the genotype distribution of the PAI-1 gene was not found to be different when compared with the unaffected controls (P>0.05, χ2=1.03). The risk allele 4G was also not associated with MI (P>0.05, χ2=0.46, odds ratio (OR)=1.1 (95% confidence interval (CI)=0.84-1.43), P>0.05). Similarly, the genotype frequencies of t-PA I/I, I/D and D/D were not different from the unaffected controls (P>0.05, χ2=1.60), and the risk allele "I" was not found to be associated with MI (P>0.05, χ2=1.35, OR=0.86 (95% CI=0.66-1.11), P>0.05). However, when the data were distributed along the lines of gender a significant association of the 4G/4G PAI-1 genotype was observed with only the female MI patients (P<0.05, z-test=2.21). When the combined genotypes of both the polymorphisms were analyzed, a significant association of MI was observed with the homozygous DD/4G4G genotype (P<0.01, z-test=2.61), which was specifically because of the female samples (P=0.01, z-test=2.53). In addition smoking (P<0.001, χ2=13.52, OR=3.45 (95% CI=1.77-6.94)), diabetes (P<0.001, χ2=22.45, OR=8.89 (95% CI=2.96-29.95)), hypertension (OR=7.76 (95% CI=2.88-22.68), P<0.001) family history (P<0.001, χ2=13.72, OR=3.7 (95% CI=1.71-8.18)) and lower HDL levels (P<0.05) were found to be significantly associated with the disease. In conclusion the PAI-1 gene polymorphism was found to have a gender specific role in the female MI patients.


Assuntos
Predisposição Genética para Doença/genética , Infarto do Miocárdio/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Ativador de Plasminogênio Tecidual/genética , HDL-Colesterol/sangue , Eletroforese em Gel de Ágar , Feminino , Frequência do Gene , Humanos , Mutação INDEL/genética , Masculino , Razão de Chances , Reação em Cadeia da Polimerase , Fatores de Risco , Fumar , Ativador de Plasminogênio Tecidual/antagonistas & inibidores
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