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1.
Neurologia (Engl Ed) ; 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36402398

RESUMO

OBJECTIVES: This study aims to evaluate the prognostic value of emergency blood test results in patients with acute ischaemic stroke. METHODS: We evaluated 592 prospectively patients with neuroimaging-confirmed ischaemic stroke admitted to our stroke unit between 2015 and 2018. We gathered emergency blood test results and calculated the neutrophil-to-lymphocyte ratio and the neutrophil-to-platelet ratio (neutrophils × 1.000/platelets). The association between blood test results and functional prognosis (as measured with the modified Rankin Scale) and such complications as haemorrhagic transformation was evaluated by logistic regression analysis. The additional predictive value of blood test parameters was assessed with receiver operating characteristic curves and the net reclassification index. RESULTS: An neutrophil-to-lymphocyte ratio ≥ 3 at admission was associated with a two-fold increase in the risk of functional dependence at 3 months (OR: 2.24; 95% CI: 1.35-3.71) and haemorrhagic transformation (OR: 2.11; 95% CI: 1.09-4.05), while an neutrophil-to-lymphocyte ratio ≥ 3.86 resulted in an increase of 2.4 times in the risk of mortality at 3 months (OR: 2.41; 95% CI: 1.37-4.26) after adjusting for the traditional predictors of poor outcomes. Patients with neutrophil-to-platelet ratio ≥ 32 presented 3 times more risk of haemorrhagic transformation (OR: 3.17; 95% CI: 1.70-5.92) and mortality at 3 months (OR: 3.07; 95% CI: 1.69-5.57). Adding these laboratory parameters to standard clinical-radiological models significantly improved discrimination and prognostic accuracy. CONCLUSIONS: Basic blood test parameters provide important prognostic information for stroke patients and should therefore be analysed in combination with standard clinical and radiological parameters to optimise ischaemic stroke management.

2.
Thromb Res ; 136(2): 445-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26118976

RESUMO

BACKGROUND: Thrombin-activatable fibrinolysis inhibitor (TAFI) plays an important role in coagulation and fibrinolysis. Whereas TAFI deficiency may lead to a haemorrhagic tendency, data from TAFI knockout mice (TAFI-/-) are controversial and no differences have been reported in these animals after ischemic stroke. There are also no data regarding the role of circulating microparticles (MPs) in TAFI-/-. OBJECTIVES: to examine the effect of tPA on the rate of intracranial haemorrhage (ICH) and on MPs generated in a model of ischemic stroke in TAFI-/- mice. METHODS: Thrombin was injected into the middle cerebral artery (MCA) to analyse the effect of tPA (10mg/Kg) on the infarct size and haemorrhage in the absence of TAFI. Immunofluorescence for Fluoro-Jade C was performed on frozen brain slides to analyse neuronal degeneration after ischemia. MPs were isolated from mouse blood and their concentrations calculated by flow cytometry. RESULTS: Compared with saline, tPA significantly increased the infarct size in TAFI-/- mice (p<0.05). Although plasma fibrinolytic activity (fibrin plate assay) was higher in these animals, no macroscopic or microscopic ICH was detected. A positive signal for apoptosis and degenerating neurons was observed in the infarct area, being significantly higher in tPA treated TAFI-/- mice (p<0.05). Interestingly, higher numbers of MPs were found in TAFI-/- plasma as compared to wild type, after stroke (p<0.05). CONCLUSIONS: TAFI deficiency results in increased brain damage in a model of thrombolysis after ischemic stroke, which was not associated with bleeding but with neuronal degeneration and MP production.


Assuntos
Carboxipeptidase B2/metabolismo , Micropartículas Derivadas de Células/metabolismo , Hemorragias Intracranianas/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Ativador de Plasminogênio Tecidual/uso terapêutico , Animais , Carboxipeptidase B2/genética , Micropartículas Derivadas de Células/efeitos dos fármacos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Acidente Vascular Cerebral/complicações , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
5.
J Thromb Haemost ; 11(8): 1464-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23742289

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs) mediate tissue injury during stroke but also neurovascular remodeling and we have shown that MMP-10 is involved in atherothrombosis. OBJECTIVE: The purpose of this study was to examine the relationship between proMMP-10 and clinical outcome, assessing inflammatory and proteolytic markers, in patients with acute ischemic stroke. METHODS: We prospectively studied 76 patients with ischemic stroke treated with tPA within the first 3 h from symptom onset, compared with 202 non-tPA-treated ischemic stroke patients and 83 asymptomatic subjects. Stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS). Hemorrhagic transformation (HT) and severe brain edema were diagnosed by cranial CT. Good functional outcome was defined as a modified Rankin scale score ≤ 2 at 90 days. Serum levels of MMP-9, proMMP-10, TIMP-1, tumor necrosis factor-α (TNFα), interleukin-6 and cellular fibronectin were measured at admission. The effect of TNFα on endothelial proMMP-10 was assessed in vitro. RESULTS: Serum proMMP-10 concentration in ischemic stroke patients, non-treated or treated with t-PA, which was higher than age-matched healthy subjects (P < 0.0001), was independently associated with higher infarct volume, severe brain edema, neurological deterioration and poor functional outcome at 3 months (all P < 0.05), but not with HT. proMMP-10 levels were also independently and positively associated with circulating levels of TNFα (P < 0.0001), which induced its endothelial expression in vitro, both mRNA and protein. MMP-9, however, was only associated with HT and severe edema (all P < 0.05). CONCLUSIONS: Increased serum proMMP-10 after acute ischemic stroke, associated with TNFα, is a new marker of brain damage and poor outcome.


Assuntos
Biomarcadores/sangue , Isquemia Encefálica/metabolismo , Regulação da Expressão Gênica , Metaloproteinase 10 da Matriz/sangue , Acidente Vascular Cerebral/metabolismo , Idoso , Estudos de Coortes , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Índice de Gravidade de Doença , Trombose/metabolismo , Fatores de Tempo , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo
6.
Thromb Haemost ; 110(3): 598-608, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23803792

RESUMO

A prothrombotic state is one of the hallmarks of malignancy and a major contributor to morbidity and mortality in cancer patients.Tissue factor (TF) is often overexpressed in malignancy and is a prime candidate in predicting the hypercoagulable state. Moreover, increased number of TF-exposing microparticles (MPs) in cancer patients may contribute to venous thromboembolism (VTE). We have conducted a prospective cohort study to determine whether elevated TF antigen, TF activity and TF associated to MPs (MPs-TF) are predictive of VTE and mortality in cancer patients. The studied population consisted of 252 cancer patients and 36 healthy controls. TF antigen and activity and MPs-TF were determined by ELISA and chromogenic assays. During a median follow-up of 10 months, 40 thrombotic events were recorded in 34 patients (13.5%), and 73 patients (28.9%) died. TF antigen and activity were significantly higher in patients than in controls (p<0.01) mainly in patients with advanced stages, whereas no differences were observed for TF activity of isolated MPs. We did not find a statistically significant association of TF variables with the risk of VTE. Multivariate analysis adjusting for age, sex, type of cancer and other confounding variables showed that TF activity (p<0.01) and MPs-TF activity (p<0.05) were independently associated with mortality. In conclusion, while TF variables were not associated with future VTE in cancer patients, we found a strong association of TF and MPs-TF activity with mortality, thus suggesting they might be good prognostic markers in cancer patients.


Assuntos
Micropartículas Derivadas de Células , Neoplasias/complicações , Neoplasias/mortalidade , Tromboplastina/metabolismo , Trombose/metabolismo , Tromboembolia Venosa/metabolismo , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Coagulantes/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Tempo
7.
Circulation ; 124(25): 2909-19, 2011 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22104553

RESUMO

BACKGROUND: The fibrinolytic and matrix metalloproteinase (MMP) systems cooperate in thrombus dissolution and extracellular matrix proteolysis. The plasminogen/plasmin system activates MMPs, and some MMPs have been involved in the dissolution of fibrin by targeting fibrin(ogen) directly or by collaborating with plasmin. MMP-10 has been implicated in inflammatory/thrombotic processes and vascular integrity, but whether MMP-10 could have a profibrinolytic effect and represent a promising thrombolytic agent is unknown. METHODS AND RESULTS: The effect of MMP-10 on fibrinolysis was studied in vitro and in vivo, in MMP-10-null mice (Mmp10(-/-)), with the use of 2 different murine models of arterial thrombosis: laser-induced carotid injury and ischemic stroke. In vitro, we showed that MMP-10 was capable of enhancing tissue plasminogen activator-induced fibrinolysis via a thrombin-activatable fibrinolysis inhibitor inactivation-mediated mechanism. In vivo, delayed fibrinolysis observed after photochemical carotid injury in Mmp10(-/-) mice was reversed by active recombinant human MMP-10. In a thrombin-induced stroke model, the reperfusion and the infarct size in sham or tissue plasminogen activator-treated animals were severely impaired in Mmp10(-/-) mice. In this model, administration of active MMP-10 to wild-type animals significantly reduced blood reperfusion time and infarct size to the same extent as tissue plasminogen activator and was associated with shorter bleeding time and no intracranial hemorrhage. This effect was not observed in thrombin-activatable fibrinolysis inhibitor-deficient mice, suggesting thrombin-activatable fibrinolysis inhibitor inactivation as one of the mechanisms involved in the MMP-10 profibrinolytic effect. CONCLUSIONS: A novel profibrinolytic role for MMP-10 in experimental ischemic stroke is described, opening new pathways for innovative fibrinolytic strategies in arterial thrombosis.


Assuntos
Infarto Cerebral/metabolismo , Fibrinólise/fisiologia , Metaloproteinase 10 da Matriz/metabolismo , Acidente Vascular Cerebral/metabolismo , Trombina/metabolismo , Animais , Tempo de Sangramento , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Doenças das Artérias Carótidas/tratamento farmacológico , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/fisiopatologia , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/prevenção & controle , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/fisiopatologia , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Feminino , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/farmacologia , Humanos , Trombose Intracraniana/tratamento farmacológico , Trombose Intracraniana/metabolismo , Trombose Intracraniana/fisiopatologia , Masculino , Metaloproteinase 10 da Matriz/genética , Metaloproteinase 10 da Matriz/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia , Ativador de Plasminogênio Tecidual/farmacologia
8.
Am J Physiol Regul Integr Comp Physiol ; 297(5): R1563-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19776253

RESUMO

Increased levels of plasminogen activator inhibitor-1 (PAI-1) have been associated with obesity, aging, insulin resistance, and type 2 diabetes, conditions that contribute to increased cardiovascular risk. PAI-1 is expressed in a variety of tissues, but the cellular origin of plasma PAI-1 is unknown. To link insulin resistance, aging, and cardiovascular disease, we examined the expression and glycosylation pattern of PAI-1 in liver and white adipose tissue (WAT) from adult (3 mo) and insulin-resistant old (24 mo) Wistar rats. Glycosylated PAI-1 protein was also purified by affinity chromatography from endothelial culture supernatans to analyze its inhibitory activity. We also analyzed the contribution of adipocytes and stromal vascular cells from WAT to PAI-1 levels with aging. Aging caused a significant increase of PAI-1 mRNA (P < 0.001) in WAT that was predominantly due to the adipocytes and not to stroma-vascular cells, while there was no modification in liver from aged rats. Moreover, PAI-1 expression increased during preadipocyte differentiation (P < 0.001). Furthermore, we found a tissue-dependent PAI-1 glycosylation pattern: adipose tissue only expresses the glycosylated PAI-1 form, whereas the liver mainly expresses the nonglycosylated form. Finally, we also found evidences suggesting that the glycosylated PAI-1 form shows higher inhibitory activity than the nonglycosylated. Our data suggest that WAT may be a major source of the elevated plasma levels of PAI-1 in insulin-resistant old rats. Additionally, the high degree of PAI-1 glycosylation and activity, together with the significant increase in visceral fat in old rats, may well contribute to an increased cardiovascular risk associated with insulin-resistant states.


Assuntos
Tecido Adiposo Branco/metabolismo , Envelhecimento/metabolismo , Resistência à Insulina/fisiologia , Fígado/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo Branco/patologia , Envelhecimento/patologia , Animais , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/fisiologia , Glicosilação , Fígado/patologia , Masculino , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
9.
Artigo em Inglês | MEDLINE | ID: mdl-17897046

RESUMO

Biomarkers are generally considered to be plasma measurements of molecules, proteins, or enzymes that provide independent diagnostic and prognostic value by reflecting an underlying disease state or condition. In the case of coronary heart disease, they must reflect the underlying biology of the vessel wall and in particular, the atherosclerotic process and/or its sequelae. The clinical utility of a biomarker depends on its ability to account for a significant proportion of the disease being evaluated; it should be accurate and reliable; provide good sensitivity and specificity; and be available for widespread application. Data are being accumulated on the potential clinical utility of markers of inflammation, hemostasis and thrombosis, phospholipases, proteolysis and oxidative stress. Whereas C-reactive protein (CRP) emerges as a biomarker in the setting of primary prevention, we have recently found that CRP enhances the endothelial expression of metalloproteinases (MMPs). Regardless of the causality, circulating inflammatory markers have the potential to refine prediction of risk of cardiovascular events. However, a recommendation that they should be added to current risk factor scores is premature, since the benefits and costs of screening with any inflammatory marker require careful evaluation. A multimarker approach to estimate cardiovascular risk either by inflammatory markers and cumulative risk markers obtained from non-invasive tests or both may be superior to assessing a single marker.


Assuntos
Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Animais , Aterosclerose/fisiopatologia , Biomarcadores , Doença da Artéria Coronariana/fisiopatologia , Humanos , Inflamação/fisiopatologia , Medição de Risco
11.
J Thromb Haemost ; 5(1): 91-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17059420

RESUMO

OBJECTIVES: Circulating levels of matrix metalloproteinase (MMP)-10 are related to inflammation in asymptomatic subjects with cardiovascular risk factors. Whether MMP-10 is associated with the severity of atherosclerosis remains to be determined. This study examines the relationship of systemic MMP-10 levels with atherosclerotic risk factors and subclinical atherosclerosis. METHODS AND RESULTS: Circulating levels of MMP-1, -9 and -10, and markers of inflammation [fibrinogen, interleukin-6, von Willebrand factor, and high-sensitivity C-reactive protein (hs-CRP)] were measured in 400 subjects (mean age 54.3 years, 77.7% men) with cardiovascular risk factors but free from clinical cardiovascular disease. Subclinical atherosclerosis was evaluated by both the mean carotid intima-media thickness (IMT) and the presence of atherosclerotic plaques with the use of B-mode ultrasound in all subjects. MMP-10 levels were positively correlated with fibrinogen (r = 0.24, P < 0.001), hs-CRP (r = 0.14, P < 0.01) and carotid IMT (r = 0.17, P < 0.01). The association between MMP-10 and IMT remained significant in multiple regression analysis (P < 0.02) when controlling for traditional atherosclerotic risk factors and inflammatory markers. Such an association was not observed for MMP-1 and -9. Subjects in the highest MMP-10 tertile had significantly higher carotid IMT (adjusted odds ratio 6.3, 95% confidence interval 1.3-31.4, P = 0.024). In addition, MMP-10 levels were significantly higher in patients with carotid plaques (n = 78) than in those with no plaques after adjusting for age and sex (P < 0.01). CONCLUSION: Higher serum MMP-10 levels were associated with inflammatory markers, increased carotid IMT and atherosclerotic plaques in asymptomatic subjects. Circulating MMP-10 may be useful to identify subclinical atherosclerosis in subjects free from cardiovascular disease.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/enzimologia , Artéria Carótida Primitiva/diagnóstico por imagem , Metaloproteinase 10 da Matriz/sangue , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/enzimologia , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/etiologia , Feminino , Fibrinogênio/metabolismo , Humanos , Interleucina-6/sangue , Modelos Lineares , Modelos Logísticos , Masculino , Metaloproteinase 1 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Índice de Gravidade de Doença , Ultrassonografia , Fator de von Willebrand/metabolismo
12.
J Thromb Haemost ; 4(8): 1798-803, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16879223

RESUMO

BACKGROUND: Increased plasminogen activator inhibitor (PAI-1) levels lead to impaired fibrinolytic function associated with higher cardiovascular risk. PAI-1 expression may be regulated by different inflammatory cytokines such as interleukin-1alpha (IL-1). Several polymorphisms have been described in the PAI-1 gene. AIM: We examined the influence of the 4G/5G polymorphism in the promoter region on IL-1alpha-induced PAI-1 expression by human umbilical vein endothelial cells (HUVEC) in presence or absence of pravastatin. METHODS AND RESULTS: Genotyped HUVEC were incubated with IL-1alpha (500 U mL(-1)) in presence or absence of pravastatin (1-10 microm). PAI-1 expression was analyzed by real time polymerase chain reaction (PCR), and PAI-1 antigen measured in supernatants by ELISA. IL-1alpha increased PAI-1 secretion in a genotype-dependent manner, and higher values were observed for 4G/4G compared with both 4G/5G and 5G/5G cultures (P < 0.05). Preincubation of HUVEC with 10 microm pravastatin significantly reduced IL-1-induced PAI-1 expression in 4G/4G HUVEC compared with untreated cultures (177.5% +/- 24.5% vs. 257.9% +/- 39.0%, P < 0.05). Pravastatin also attenuated the amount of secreted PAI-1 by 4G/4G HUVEC after IL-1 stimulation (5020.6 +/- 165.7 ng mL(-1) vs. 4261.1 +/- 309.8 ng mL(-1), P < 0.05). This effect was prevented by coincubation with mevalonate, indicating a dependence on HMG-CoA reductase inhibition. CONCLUSIONS: The endothelial 4G/5G PAI-1 genotype influences the PAI-1 response to IL-1alpha and the modulatory effect of pravastatin. As increased PAI-1 levels have been linked to cardiovascular disease the observed endothelial modulation by pravastatin may have potential clinical implications.


Assuntos
Endotélio Vascular/metabolismo , Interleucina-1/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Polimorfismo Genético , Pravastatina/farmacologia , Regiões Promotoras Genéticas , Análise de Variância , Aterosclerose , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Genótipo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Veias Umbilicais/citologia
13.
Clin Chim Acta ; 368(1-2): 138-43, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16458279

RESUMO

BACKGROUND: Cyclooxygenase (COX)-2, a key regulatory enzyme in prostanoid synthesis, plays an important role in inflammatory processes. The -765G>C COX-2 polymorphism has been associated with lower promoter activity in vitro and reduced levels of C-reactive protein (CRP) in atherosclerotic carriers of the C allele. However, its pathophysiological relevance in vivo has not been fully elucidated. METHODS AND RESULTS: We assessed the -765G>C polymorphism and COX-2 expression in 220 asymptomatic subjects free of cardiovascular disease, in relation to global vascular risk, carotid intima-media thickness (IMT), and inflammatory markers (fibrinogen, C-reactive protein [CRP], von Willebrand factor [vWF] and interleukin-6 [IL-6]). Genotype frequencies were: CC (7.7%), CG (34.5%), GG (57.7%). Among hypercholesterolemic subjects (n=140), C allele carriers had lower COX-2 expression (p<0.05), reduced carotid IMT (p<0.01) and diminished levels of inflammatory markers CRP, vWF and IL-6 (p<0.05), as compared to GG homozygous subjects. The association between carotid IMT and COX-2 polymorphism remained significant after adjusting for cardiovascular risk factors and inflammatory markers (p=0.008). CONCLUSIONS: In asymptomatic hypercholesterolemic subjects the C allele of -765G>C COX-2 polymorphism was associated with lower COX-2 expression, and reduced subclinical atherosclerosis and systemic inflammation compared with GG homozygous, thus conferring atherosclerosis protection in this cardiovascular risk population.


Assuntos
Aterosclerose/diagnóstico , Aterosclerose/genética , Ciclo-Oxigenase 2/genética , Cisteína/genética , Glicina/genética , Polimorfismo Genético/genética , Aterosclerose/classificação , Aterosclerose/enzimologia , Biomarcadores , Colesterol/sangue , Feminino , Regulação Enzimológica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Monócitos/enzimologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-16101563

RESUMO

It is now widely accepted that atherosclerosis is a complex chronic inflammatory disorder of the arterial tree associated with several risk factors. From the initial phases of leukocyte recruitment to eventual rupture of vulnerable atherosclerotic plaques, a low-grade inflammation, also termed microinflammation, appears to play a key pathogenetic role. Experimental and clinical evidence suggests that cyclooxygenase-2 (COX-2), an enzyme which catalyzes the generation of prostaglandins from arachidonic acid, also contributes to lesion formation. COX-2 has been detected in macrophages, smooth muscle cells and endothelial cells in human atherosclerotic lesions. Several studies have also reported the presence of COX-2 in the shoulder region of atherosclerotic plaques, mainly colocalizing with macrophages and MMPs, enzymes that are involved in the destabilization of atherosclerotic plaques, leading to rupture and atherothrombotic syndromes (i.e. acute myocardial infarction). We have recently assessed monocyte COX-2 activity and the production of PGE(2) in a population of apparently healthy subjects free from clinically overt atherosclerosis. We found an association between increased PGE(2) and increasing number of cardiovascular risk factors and carotid intima-media thickness, a noninvasive surrogate marker of atherosclerosis, independently of traditional and non traditional cardiovascular risk factors. Our findings support the notion that the COX-2/PGE(2)axis may have a role in atherosclerosis, and this might be an attractive therapeutic target. COX-2 inhibitors, collectively called coxibs (celecoxib, rofecoxib, valdecoxib, lumiracoxib, etc), held a promise of improved treatment of arthritis without the gastrointestinal side effects associated with aspirin and other nonsteroidal anti-inflammatory drugs. However, clinical studies raise several clinically relevant questions as to their beneficial role in atherosclerosis prevention, because of increased thrombogenicity and cardiovascular risk. Only well designed large scale clinical trials can provide the answer as to the net effect of selective COX-2 inhibition on cardiovascular events before this new class of anti-inflammatory drugs can be incorporated into the armamentarium of atherosclerosis.


Assuntos
Arteriosclerose/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Monócitos/enzimologia , Prostaglandina-Endoperóxido Sintases/sangue , Arteriosclerose/enzimologia , Arteriosclerose/fisiopatologia , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Dinoprostona/metabolismo , Humanos , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/fisiologia
15.
Clín. investig. arterioscler. (Ed. impr.) ; 17(3): 133-141, mayo-jun. 2005. ilus, tab
Artigo em Es | IBECS | ID: ibc-037868

RESUMO

Las metaloproteasas son una familia de endopeptidasas que degradan proteínas de la matriz extracelular y desempeñan un papel importante en diversos procesos fisiológicos (p. ej., cicatrización de heridas) y patológicos, como cáncer, angiogenia y aterosclerosis. Existen evidencias experimentales y clínicas que sugieren que las metaloproteasas son relevantes en el remodelado vascular y degradación de la placa fibrosa, que complican la evolución de los pacientes con aterosclerosis al favorecer la trombosis y la formación de aneurismas. Se ha observado en arterias humanas un diferente patrón de expresión de metaloproteasas según el tipo de lesión aterosclerótica y del lecho vascular implicado. Asimismo, se ha encontrado un aumento de metaloproteasas en la circulación de pacientes con síndromes coronarios. Estudios experimentales indican que la inhibición de las metaloproteasas puede ser importante en la estabilización de la placa de ateroma y constituir nuevas dianas terapéuticas en el tratamiento de la aterosclerosis


Metalloproteases (MMPs) constitute a family of endopeptidases which break down extracellular matrix proteins and play an important role in different physiologic (wound scarring) and pathologic processes such as cancer, angiogenesis and atherosclerosis. Experimental and clinical evidence suggests that MMPs are important in vascular remodeling and fibrous plaque breakdown which complicate the evolution of patients with atherosclerosis by favoring thrombosis and aneurysm formation. A different MMP expression pattern depending on the type of atherosclerotic lesion and vascular bed involved has been observed in human arteries. Similarly, an increase in MMPs has been found in the bloodstream of patients with coronary syndromes. Experimental studies indicate that MMP inhibition may be important in atheromatous plaque stabilization and constitute new therapeutic targets in atherosclerosis management


Assuntos
Adulto , Humanos , Metaloproteases/sangue , Metaloproteases/fisiologia , Arteriosclerose/fisiopatologia , Arteriosclerose/terapia , Matriz Extracelular/genética , Matriz Extracelular/fisiologia , Endopeptidases/fisiologia , Vitaminas , Arteriosclerose/prevenção & controle , Cicatrização/fisiologia , Antioxidantes/fisiologia , Vitaminas/fisiologia
16.
J Thromb Haemost ; 3(4): 662-4, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15842351

RESUMO

Von Willebrand factor (VWF) is considered a reliable marker of endothelial damage. Plasma levels of VWF were measured in 857 middle-aged subjects (80.4% men) free of clinically overt atherosclerotic disease, in relation to cardiovascular risk factors, carotid intima-media thickness (IMT) and microalbuminuria, two established surrogate markers of atherosclerosis. There was linear trend for the increase of VWF, carotid IMT (p < 0.001) and microalbuminuria (p = 0.018). The association between VEF and both markers remained statistically significant after adjusting for cardiovascular risk factors and inflammatory markers (p < 0.01). In conclusion, VWF was independently associated with both structural and functional surrogates of atherosclerosis in asymptomatic subjects, thus representing a systemic biomarker of subclinical atherosclerosis.


Assuntos
Arteriosclerose/sangue , Arteriosclerose/diagnóstico , Fator de von Willebrand/biossíntese , Adulto , Idoso , Albuminúria/metabolismo , Biomarcadores , Testes de Coagulação Sanguínea/métodos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Túnica Íntima/patologia , Túnica Média/patologia , Doenças Vasculares/diagnóstico
18.
Cardiovasc Res ; 63(1): 176-85, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15194475

RESUMO

BACKGROUND: We examined the influence of the 4G/5G PAI-1 (plasminogen activator inhibitor) genotype on Angiotensin II (Ang II)-induced PAI-1 expression by human endothelial cells (HUVEC) in the presence and absence of AT1-receptor blocker losartan, and screened for this polymorphism in relation to plasma PAI-1 and arterial pressure in apparently healthy subjects. METHODS AND RESULTS: Genotyped cultured HUVEC were incubated with Ang II (10(-8) M) with or without losartan up to 24 h. PAI-1 mRNA was determined in cell extracts and protein and activity assessed in supernatants and extracellular matrix (ECM). Ang II increased PAI-1 mRNA and activity in a genotype-dependent manner, higher values observed for 4G/4G HUVEC compared with 4G/5G and 5G/5G genotypes (p<0.05). Laser confocal microscopy and Western blot analysis showed increased PAI-1 protein within ECM in Ang II-stimulated cultures. PAI-1 expression and protein secretion induced by Ang II in 4G/4G HUVEC was completely inhibited by preincubation with 0.05 microM losartan (p<0.01), indicating an AT1-mediated effect. In a group of hypertensives homozygous for the 4G allele, PAI-1 antigen was significantly increased (51.0+/-10.1 ng/ml) compared with normotensives (28.3+/-4.0 ng/ml) and hypertensives carrying the 5G allele (p<0.05). CONCLUSIONS: The 4G/5G PAI-1 polymorphism determines the endothelial PAI-1 upregulation by Ang II and the inhibitory response to losartan. Analysis of PAI-1 genotypes may help identifying subgroups of hypertensives at higher cardiovascular risk.


Assuntos
Angiotensina II/farmacologia , Células Endoteliais/metabolismo , Hipertensão/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Polimorfismo Genético , Análise de Variância , Bloqueadores do Receptor Tipo 1 de Angiotensina II , Estudos de Casos e Controles , Células Cultivadas , Feminino , Fibrinólise , Marcadores Genéticos , Genótipo , Humanos , Losartan/farmacologia , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/imunologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não Paramétricas , Estimulação Química
19.
Stroke ; 35(5): 1085-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15017006

RESUMO

BACKGROUND AND PURPOSE: Thrombin, a central enzyme in the clotting cascade, plays a role not only in thrombosis but also in the progression of atherosclerosis. We studied the relationship between prothrombin fragment 1+2 (F1+2), a specific marker of thrombin generation in vivo, and carotid intima-media thickness (IMT), an index of subclinical atherosclerosis. METHODS: We examined 181 asymptomatic middle-aged subjects (mean age 55.6 years, 76.7% men) free of overt clinical atherosclerotic disease. F1+2 was measured by enzyme-linked immunosorbent assay and IMT by duplex ultrasonography of carotid artery. Multiple linear regression analysis was used to assess the relationship between the 2 parameters. RESULTS: Compared with individuals in the lowest tertile of F1+2, those in the upper tertile (>0.55 nmol/L) showed significantly higher IMT (P<0.01). In correlation analysis, a positive relationship was found between plasma F1+2 and carotid IMT. F1+2 also correlated positively with cholesterol (P<0.008) and low-density lipoprotein cholesterol (P<0.005), but not with blood pressure or body mass index. In the multivariate analysis, the association of F1+2 with carotid IMT remained significant (P<0.001) after adjustment for age, sex, body mass index, systolic blood pressure, cholesterol, diabetes, and smoking. CONCLUSIONS: In a population sample of adults without clinically overt atherosclerotic disease, the plasma levels of F1+2 were significantly associated with carotid IMT, suggesting a relationship between thrombin generation and the development atherosclerosis.


Assuntos
Arteriosclerose , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/patologia , Fragmentos de Peptídeos/sangue , Túnica Íntima/patologia , Arteriosclerose/etiologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Protrombina , Análise de Regressão , Fatores de Risco , Túnica Íntima/diagnóstico por imagem , Ultrassonografia Doppler Dupla/estatística & dados numéricos
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