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1.
J Thromb Thrombolysis ; 37(3): 317-25, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23575879

RESUMO

Factor VII Activating Protease (FSAP) activates factor VII (FVII) as well as pro-urokinase (uPA). Our goal was to evaluate the relation between plasma levels of FSAP and clinical instability in atrial fibrillation (AF) and possible effects of oral omega-3 fatty acids (FA) supplements. 101 patients with persistent AF were analyzed in the OMEGA-AF Study. Plasma FSAP levels were measured at baseline and after 12 weeks of treatment with omega-3 FA. The median FSAP antigen concentration, in contrast to FSAP activity, was higher in patients with persistent AF. The maintenance of SR after successful cardioversion (CV) did not lead to a normalization of FSAP concentration. Supplementation with omega-3 FA but not placebo significantly reduced elevated FSAP concentration. Furthermore, elevated FSAP levels did not indicate a significantly increased risk of recurrence of AF after electrical CV or cardiovascular clinical events during 1 year of follow-up. Plasma FSAP concentration was increased in patients with AF and may be involved in the pathogenesis of this condition. The possible effects of omega-3 FA on clinical AF potential could be linked with modulation of circulating FSAP levels.


Assuntos
Fibrilação Atrial/sangue , Fibrilação Atrial/dietoterapia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Serina Endopeptidases/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
2.
Atherosclerosis ; 230(2): 365-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24075769

RESUMO

OBJECTIVE: Factor VII activating protease (FSAP) is a novel regulator of vascular inflammation and hemostasis. However, the molecular mechanism by which circulating FSAP influences inflammatory events and progression of atherosclerosis is not yet entirely understood. Here we have investigated the influence of FSAP on monocyte/macrophage functions. METHODS: We stimulated human monocyte-derived macrophages with FSAP and analyzed their cellular responses. RESULTS: FSAP induced IκB-dependent NF-κB activation in a time- and concentration-dependent fashion. FSAP also activated the phosphorylation and proteolytic degradation of the inhibitor protein IκBα. The phosphorylation of the p65 subunit of NF-κB was induced by FSAP, which is known to contribute to the enhancement of DNA-binding activity of NF-κB. Concomitantly, FSAP up-regulated the expression of pro-inflammatory cytokines, matrix metalloproteinases, cell adhesion molecules and tissue factor. In the presence of FSAP there was increased monocytes adhesion and transendothelial migration in a beta2 integrin dependent manner. CONCLUSIONS: Our findings suggest that FSAP activates the NF-κB pathway and the associated downstream pro-inflammatory factors in monocytic cells. This adds to a spectrum of FSAP effects on the vascular system that may explain its association with cardiovascular diseases.


Assuntos
Regulação da Expressão Gênica , Macrófagos/metabolismo , Monócitos/metabolismo , Serina Endopeptidases/metabolismo , Aterosclerose/patologia , Doenças Cardiovasculares/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Proteínas I-kappa B/metabolismo , Inflamação , Leucócitos Mononucleares/citologia , Macrófagos/citologia , Monócitos/citologia , NF-kappa B/metabolismo , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fatores de Tempo
3.
Eur J Obstet Gynecol Reprod Biol ; 167(1): 34-40, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23218959

RESUMO

OBJECTIVES: Factor seven activating protease (FSAP) is a plasma serine protease known to play a critical role in hemostasis and remodeling processes: FSAP levels increase markedly during normal pregnancy. In order to define the role of FSAP in vascular pathophysiology in pregnant women and particularly in the placenta, we performed this study (i) to evaluate the FSAP expression in human placenta and (ii) to identify the role of FSAP in human trophoblast migration. STUDY DESIGN: FSAP expression in placental tissues was analyzed by using immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). To determine whether FSAP plays any role in trophoblast migration, we used human trophoblast cells in transwell migration assays. RESULTS: Immunohistochemistry showed that FSAP protein was expressed by syncytiotrophoblast and in the cytoplasma of invasive extravillous trophoblasts (EVT) within the maternal decidua (DC) in implantation sites of human first trimester placenta. Furthermore, FSAP mRNA and protein decreased with gestational age (p<0.05, 1st vs 3rd trimester). FSAP (10µg/ml) had a significant stimulatory effect on the migration of human trophoblast cells. This effect was abolished by addition of aprotinin to block the enzymatic activity of FSAP. CONCLUSIONS: The high expression level of FSAP in the placenta supports a relevant role of this protease in trophoblast migration and vascular remodeling, identifies a new concept of coagulation/fibrinolysis at the feto-maternal interface and may be essential for the maintenance of pregnancy.


Assuntos
Movimento Celular/fisiologia , Placenta/enzimologia , Serina Endopeptidases/metabolismo , Trofoblastos/fisiologia , Análise de Variância , Ensaios de Migração Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Expressão Gênica , Idade Gestacional , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Terceiro Trimestre da Gravidez , RNA Mensageiro/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/farmacologia
4.
Circ J ; 76(11): 2653-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22850287

RESUMO

BACKGROUND: Factor VII activating protease (FSAP) is a circulating serine protease strongly expressed in unstable plaques and may serve as a marker of plaque destabilization. The aim of this study was to examine the relation between plasma concentrations of FSAP and clinical instability and outcome in coronary artery disease (CAD). METHODS AND RESULTS: Circulating FSAP concentration and activity, as well as FSAP mRNA expression in monocytes, were measured in 231 sequential patients who underwent coronary angiography because of stable angina pectoris (n=50), unstable angina pectoris (n=43), or acute myocardial infarction (n=87). FSAP activity, but not FSAP antigen concentration, was elevated in patients with CAD compared with a control group. Elevated FSAP activity (≥1.035 plasma equivalent units [PEU]/ml) indicated a significantly increased risk of death or non-fatal myocardial infarction during 1 year of follow-up as compared with patients with low activity of FSAP (odds ratio 1.895 [95% confidence interval 1.093-3.283]; P=0.023). Furthermore, there were no significant changes in the FSAP expression in monocytes from CAD and control subjects in the basal state but there were differences after stimulation with proinflammatory factors. CONCLUSIONS: Plasma FSAP activity was significantly increased in patients with acute coronary syndrome and may be involved in the pathogenesis of these conditions. High levels of FSAP activity were predictive of adverse events during follow-up, suggesting its potential role in risk stratification and clinical management of CAD patients.


Assuntos
Síndrome Coronariana Aguda/sangue , Regulação Enzimológica da Expressão Gênica , Monócitos/enzimologia , Serina Endopeptidases/sangue , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/mortalidade , Idoso , Angiografia Coronária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , RNA Mensageiro/biossíntese , Fatores de Risco , Fatores de Tempo
5.
J Atheroscler Thromb ; 19(11): 962-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22878700

RESUMO

AIM: Factor VII activating protease (FSAP) is a plasma serine protease involved in hemostasis and remodeling processes. Increased levels of circulating FSAP during pregnancy and in women using oral contraceptives (OCs) indicate that the hormonal status critically influences FSAP expression. In this respect, the aim of this study was to quantify nicotine modulation of FSAP expression in human monocytes/macrophages isolated from healthy female smokers and non-smokers, and from women who use OCs and smoke. METHODS: FSAP concentration and activity were measured in plasma samples obtained from healthy non-pregnant, pre-menopausal, non-smoking women who did not use OCs (n=69), non-pregnant, pre-menopausal women who currently smoke and use OCs (n=43), and women who are only smokers (n=40) or currently use OCs (n=48). Expressions of FSAP mRNA and protein in monocytes isolated from healthy non-pregnant female or healthy male donors were analyzed. RESULTS: Strongest circulating FSAP concentration and activity occurred in women with combined smoking and use of OCs compared to the control group. Enhanced FSAP levels were also observed in smoking women when compared to non-smokers. Ex vivo experiments demonstrated enhanced FSAP expression in monocytes isolated from women using OCs and currently smoking. Nicotine enhanced FSAP mRNA and protein levels in monocytes. CONCLUSIONS: Monocytes from healthy female smokers show a constitutively enhanced FSAP expression and this effect could be replicated in vitro by stimulating monocytes with nicotine. The upregulation of FSAP due to nicotine and OC usage may be linked to a higher incidence of arteriothromboembolic diseases related to their usage.


Assuntos
Monócitos/metabolismo , Nicotina/farmacologia , Serina Endopeptidases/efeitos dos fármacos , Western Blotting , Estudos de Casos e Controles , Feminino , Humanos , Masculino , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Fumar/sangue
6.
Artigo em Inglês | MEDLINE | ID: mdl-21769261

RESUMO

Tako-Tsubo cardiomyopathy (TTC) is an acute reversible cause of segmental myocardial dysfunction that is poorly understood and cannot be explained by the occlusion of a single coronary vessel. Its clinical presentation is similar to that of acute coronary syndrome and is often precipitated by a severe psychological or physical stress.

7.
Clin Med Insights Cardiol ; 5: 45-7, 2011 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-21573037

RESUMO

Effective cardiac resynchronization therapy (CRT) requires an accurate atrio-biventricular pacing system. The innovative Quartet lead is a quadripolar, over-the-wire left ventricular lead with four electrodes and has recently been designed to provide more options and greater control in pacing vector selection. A lead with multiple pacing electrodes is a potential alternative to physical adjustment of the lead and may help to overcome high thresholds and phrenic nerve stimulation (PNS).

8.
J Cell Mol Med ; 15(11): 2478-85, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21199327

RESUMO

Uncontrolled release of Ca(2+) from the sarcoplasmic reticulum (SR) contributes to the reperfusion-induced cardiomyocyte injury, e.g. hypercontracture and necrosis. To find out the underlying cellular mechanisms of this phenomenon, we investigated whether the opening of mitochondrial permeability transition pores (MPTP), resulting in ATP depletion and reactive oxygen species (ROS) formation, may be involved. For this purpose, isolated cardiac myocytes from adult rats were subjected to simulated ischemia and reperfusion. MPTP opening was detected by calcein release and by monitoring the ΔΨ(m). Fura-2 was used to monitor cytosolic [Ca(2+)](i) or mitochondrial calcium [Ca(2+)](m), after quenching the cytosolic compartment with MnCl(2). Mitochondrial ROS [ROS](m) production was detected with MitoSOX Red and mag-fura-2 was used to monitor Mg(2+) concentration, which reflects changes in cellular ATP. Necrosis was determined by propidium iodide staining. Reperfusion led to a calcein release from mitochondria, ΔΨ(m) collapse and disturbance of ATP recovery. Simultaneously, Ca(2+) oscillations occurred, [Ca(2+)](m) and [ROS](m) increased, cells developed hypercontracture and underwent necrosis. Inhibition of the SR-driven Ca(2+) cycling with thapsigargine or ryanodine prevented mitochondrial dysfunction, ROS formation and MPTP opening. Suppression of the mitochondrial Ca(2+) uptake (Ru360) or MPTP (cyclosporine A) significantly attenuated Ca(2+) cycling, hypercontracture and necrosis. ROS scavengers (2-mercaptopropionyl glycine or N-acetylcysteine) had no effect on these parameters, but reduced [ROS](m). In conclusion, MPTP opening occurs early during reperfusion and is due to the Ca(2+) oscillations originating primarily from the SR and supported by MPTP. The interplay between Ca(2+) cycling and MPTP promotes the reperfusion-induced cardiomyocyte hypercontracture and necrosis. Mitochondrial ROS formation is a result rather than a cause of MPTP opening.


Assuntos
Cálcio/metabolismo , Mitocôndrias Cardíacas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Ciclosporina/farmacologia , Fluoresceínas/análise , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial , Necrose , Ratos , Ratos Wistar , Compostos de Rutênio/farmacologia , Rianodina/farmacologia , Tapsigargina/farmacologia , Tiopronina/farmacologia
9.
Arterioscler Thromb Vasc Biol ; 30(10): 1890-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20576944

RESUMO

OBJECTIVE: Bone marrow-derived progenitor cells have been implicated to contribute to neointima formation, but the time course and extent of their accumulation and differentiation into vascular cells and, most importantly, the long-term contribution of bone marrow-derived progenitor cells to the vascular lesion remain undefined. METHODS AND RESULTS: Wire-induced injury of the femoral artery was performed on chimeric C57BL/6 mice transplanted with bone marrow from transgenic mice expressing enhanced green fluorescence protein, and vessels were harvested at 3 days, 1, 2, 3, 4, 6, and 16 weeks after dilatation (n=8 animals per time point). Using high-resolution microscopy, we unexpectedly found that the expression of smooth muscle cell or endothelial cell markers in enhanced green fluorescence protein positive cells was a very rare event. Indeed, most of the enhanced green fluorescence protein positive cells that accumulated during the acute inflammatory response were identified as monocytes/macrophages, and their number declined at later time points. In contrast, a substantial fraction of highly proliferative stem cell antigen-1 and CD34(+) but enhanced green fluorescence protein negative and thus locally derived cells were detected in the adventitia. CONCLUSIONS: These data provide evidence that the differentiation of bone marrow-derived progenitor cells into smooth muscle cell or endothelial cell lineages seems to be an exceedingly rare event. Moreover, the contribution of bone marrow-derived cells to the cellular compartment of the neointima is limited to a transient period of the inflammatory response.


Assuntos
Células-Tronco Hematopoéticas/patologia , Miócitos de Músculo Liso/patologia , Túnica Íntima/patologia , Animais , Células da Medula Óssea/patologia , Transplante de Medula Óssea , Diferenciação Celular , Tecido Conjuntivo/patologia , Artéria Femoral/lesões , Artéria Femoral/patologia , Proteínas de Fluorescência Verde/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Neovascularização Patológica , Proteínas Recombinantes/genética , Fatores de Tempo , Túnica Íntima/lesões
10.
J Atheroscler Thromb ; 17(10): 1003-8, 2010 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-20551578

RESUMO

AIM: To determine whether high plasma levels or activities of different hemostatic proteins contribute to the development of early atherosclerotic vessel wall changes. Elevated levels of various hemostatic proteins and markers of inflammation have been linked to an increased risk of ischemic cardiovascular events; however, the mechanisms by which these molecules might contribute to this increased risk is not clear. METHODS: The intima-media thickness of the common carotid arteries (CCA-IMT) of 125 healthy young volunteers without known cardiovascular risk factors was measured by high-resolution ultrasound. Plasma concentrations of fibrinogen, thrombomodulin, protein Z and CRP were quantified, and the plasma activities of protein C, plasminogen and factor VIII were measured. Other established risk factors, such as body mass index (BMI) and plasma levels of cholesterol, triglycerides and homocysteine, were also determined. Furthermore, the carotid arteries were examined for the presence of plaques and stenoses. RESULTS: Univariate analysis showed a significant negative correlation between CCA-IMT and HDL cholesterol, and positive correlations with age, BMI, LDL cholesterol, triglycerides, homocysteine, fibrinogen and thrombomodulin, but not with total cholesterol, lipoprotein(a) and hsCRP. CCA-IMT was also statistically independent of the activities of protein C, factor VIII and plasminogen. Multivariate analysis revealed a significant correlation of CCA-IMT with age, BMI and fibrinogen. CONCLUSION: Our data suggest that fibrinogen levels correlate with early atherosclerotic changes of the carotid artery in a population with very low cardiovascular risk.


Assuntos
Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Primitiva/fisiopatologia , Fibrinogênio/metabolismo , Túnica Íntima/patologia , Túnica Média/patologia , Adolescente , Adulto , Fatores Etários , Pressão Sanguínea , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Doenças das Artérias Carótidas/metabolismo , Artéria Carótida Primitiva/metabolismo , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Triglicerídeos/sangue , Ultrassonografia Doppler em Cores , Adulto Jovem
11.
J Cardiovasc Electrophysiol ; 21(10): 1109-13, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20455982

RESUMO

INTRODUCTION: Radiofrequency (RF) catheter ablation has been established as an effective and curative treatment for atrial flutter (AFL). Approved methods include a drag-and-drop method, as well as a point-by-point ablation technique. The aim of this study was to compare the acute efficacy and procedural efficiency of a multipolar linear ablation catheter with simultaneous energy delivery to multiple catheter electrodes against conventional RF for treatment of AFL. METHODS: Patients presenting to our department with symptomatic, typical AFL were enrolled consecutively and randomized to conventional RF ablation with an 8-mm tip catheter (ConvRF) or a duty-cycled, bipolar-unipolar RF generator delivering power to a hexapolar tip-versatile ablation catheter (T-VAC) group. For both groups, the procedural endpoint was bidirectional cavotricuspid isthmus block. RESULTS: Sixty patients were enrolled, 30 patients each assigned to ConvRF and T-VAC groups. Total procedure time (40.2 ± 15.8 min vs 60.5 ± 12.7 min), energy delivery time (8.5 ± 3.7 min vs 14.7 ± 5.2 min), radiation dose (14.5 ± 3.5 cGy/cm² vs 31.7 ± 12.1 cGy/cm²), and the minimum number of RF applications needed to achieve block (4.2 ± 2.4 vs 8.9 ± 7.2) were significantly lower in the T-VAC group. In 7 patients treated with the T-VAC catheter, bidirectional block was achieved with less than 3 RF applications, versus no patients with conventional RF energy delivery. CONCLUSION: The treatment of typical AFL using a hexapolar catheter with a multipolar, duty-cycled, bipolar-unipolar RF generator offers comparable effectiveness relative to conventional RF while providing improved procedural efficiency.


Assuntos
Flutter Atrial/diagnóstico , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Idoso , Feminino , Humanos , Masculino , Resultado do Tratamento
12.
Clin Res Cardiol ; 99(10): 627-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20440621

RESUMO

INTRODUCTION: Chest pain and chest discomfort are common problems in the acute care setting. Life-threatening causes of chest pain must be quickly differentiated from other less serious causes. There is a need to stratify risk rapidly in patients presenting to the emergency department (ED) with chest pain. This study evaluates the relationship between the GRACE risk score (GRS) and in-hospital mortality in patients presenting to the ED with chest pain of all causes. METHODS: We conducted a prospective study of a consecutive sample of 1,014 patients with chest pain and chest discomfort presenting to the medical ED of the University Clinic in Giessen, Germany. The GRS was calculated for each patient at admission. Additionally, the reason for admission into the hospital and the diagnosis on discharge or diagnosis of death were recorded. The relative risk between the risk groups was assessed, and the functional dependency between the GRS and observed in-hospital death was analyzed. RESULTS: A total of 94 patients died during the stay in the hospital, 83 patients with high risk, 9 with medium risk, and 2 with low risk. The risk of in-hospital death was 24.5% for high-risk patients, 2.6% for medium-risk patients, and 0.6% for patients with low risk. The correlation between the GRS and in-hospital mortality is strongly positive (p < 0.01). CONCLUSION: This study shows that the GRS accurately stratifies risk of intra-hospital mortality in patients presenting to the ED with chest pain and can guide patient triage and management.


Assuntos
Dor no Peito/mortalidade , Mortalidade Hospitalar , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco
13.
Thromb Res ; 126(1): e36-40, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20381831

RESUMO

INTRODUCTION: Factor seven activating protease (FSAP) is a plasma serine protease involved in haemostasis and remodeling processes. We have investigated whether pregnancy or the use of oral contraceptives (OCs) influences circulating FSAP levels. The effect of female sex hormones on FSAP expression in cultured cells was also determined. MATERIALS AND METHODS: FSAP levels and activity was measured in plasma samples obtained at different gestation stages from healthy pregnant women (n=101), from non-pregnant women, pre-menopausal women who currently use OCs (n=48), and non-pregnant women who did not use OCs (n=69). RESULTS: In late pregnancy the plasma FSAP antigen (median 2.28 PEU/ml [range 1.11 to 2.62 PEU/ml]; p<0.001 vs control group) and activity (median 2.98 PEU/ml [range 1.05 to 4.24 PEU/ml]; p<0.001 vs control group) was significantly higher compared with levels in non-pregnant women and remained elevated after delivery. Plasma FSAP levels in women using OCs was also significantly elevated compared to the control group. Ex vivo experiments demonstrated enhanced FSAP expression in monocytes isolated from women using OCs. In vitro experiments showed that FSAP mRNA levels were strongly induced by estradiol in monocytes but not in hepatocytes. CONCLUSIONS: Increased levels of circulating FSAP in pregnancy and in women using OCs indicate that hormonal status critically influences FSAP expression. Hormonal influences could be observed in monocytes in vivo and ex-vivo but not in hepatocytes indicating cell-specific regulation. Future studies designed to investigate the role of FSAP in haemostasis and remodeling processes should consider the role of female sex hormones on FSAP expression.


Assuntos
Anticoncepcionais Orais/farmacologia , Adolescente , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Anticoncepção , Estradiol/farmacologia , Feminino , Hemostasia/efeitos dos fármacos , Humanos , Gravidez , Estudos Prospectivos , Serina Proteases/farmacologia , Adulto Jovem
14.
Arterioscler Thromb Vasc Biol ; 30(6): 1237-45, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20339116

RESUMO

OBJECTIVE: Insulin is a key regulator of metabolism, but it also confers protective effects on the cardiovascular system. Here, we analyze the mechanism by which insulin stabilizes endothelial barrier function. METHODS AND RESULTS: Insulin reduced basal and antagonized tumor necrosis factor-alpha-induced macromolecule permeability of rat coronary microvascular endothelial monolayers. It also abolished reperfusion-induced vascular leakage in isolated-perfused rat hearts. Insulin induced dephosphorylation of the regulatory myosin light chains, as well as translocation of actin and vascular endothelial (VE)-cadherin to cell borders, indicating a reduction in contractile activation and stabilization of cell adhesion structures. These protective effects were blocked by genistein or Hydroxy-2-naphthalenylmethylphosphonic acid tris acetoxymethyl ester (HNMPA-[AM](3)), a pan-tyrosine-kinase or specific insulin-receptor-kinase inhibitor, respectively. Insulin stimulated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and NO production, and it activated Rac1. Inhibition of PI3K/Akt abrogated Rac1 activation and insulin-induced barrier protection, whereas inhibition of the endothelial nitric oxide synthase/soluble guanylyl cyclase pathway partially inhibited them. Inhibition of Rac1 abrogated the assembly of actin at cell borders. Accordingly, it abolished the protective effect of insulin on barrier function of the cultured endothelial monolayer, as well as the intact coronary system of ischemic-reperfused hearts. CONCLUSIONS: Insulin stabilizes endothelial barrier via inactivation of the endothelial contractile machinery and enhancement of cell-cell adhesions. These effects are mediated via PI3K/Akt- and NO/cGMP-induced Rac1 activation.


Assuntos
Permeabilidade Capilar , Vasos Coronários/enzimologia , Células Endoteliais/enzimologia , Insulina/metabolismo , Microvasos/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Adesão Celular , Células Cultivadas , Vasos Coronários/citologia , Vasos Coronários/efeitos dos fármacos , GMP Cíclico/metabolismo , Células Endoteliais/efeitos dos fármacos , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/metabolismo , Masculino , Microvasos/citologia , Microvasos/efeitos dos fármacos , Cadeias Leves de Miosina/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Ratos Wistar , Receptor de Insulina/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Guanilil Ciclase Solúvel , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores
15.
J Cardiovasc Pharmacol ; 55(2): 213-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20040887

RESUMO

Restenosis after balloon angioplasty or stent placement is characterized by local accumulation of mainly vascular smooth muscle cells and the synthesis of extracellular matrix molecules (ECM).We hypothesized that inhibition of ECM synthesis represents a strategy to prevent trauma-induced neointima formation. Rats were treated with pirfenidone (1 g/kg of body weight orally.), an inhibitor of growth factor-induced collagen synthesis, and subjected to balloon denudation of the carotid artery. Two weeks later, computer-aided morphometry was done and compared with untreated controls (each n = 6). Neointimal proliferative activity was quantified immunohistochemically by counting PCNA-positive nuclei, and collagen deposition was visualized by picrosirius red staining and semi-quantified by Northern blot. Control-injured animals developed marked neointimal thickening within 2 weeks (I/M, mean intima to media ratio: 2.42 +/- 0.15) resulting in an 89.2% luminal narrowing. The neointima mainly consisted of vascular smooth muscle cells embedded in collagen. Neointima formation was strongly reduced when balloon-injured animals had been treated with pirfenidone (I/M ratio 0.22 +/- 0.08, P < 0.001), resulting in a minimal residual narrowing of the lumen (7.9%). I/M ratio did not further increase even after discontinuation of the drug for 14 days (0.35 +/- 0.13). Proliferative activity within the neointima was unaffected by the drug, 4.4% versus 4.8% of neointimal cells stained positive for PCNA in carotid arteries of treated versus untreated animals, respectively. However, picrosirius red staining demonstrated marked attenuation of collagen deposition, a finding that was further confirmed by Northern blot of homogenized vessels. Pirfenidone, currently being investigated clinically for the treatment of various fibrotic diseases, is able to prevent neointimal lesion formation most likely through inhibition of local ECM deposition. Targeting matrix deposition may have an intriguing potential for the prevention of vascular proliferative diseases.


Assuntos
Angioplastia com Balão/efeitos adversos , Reestenose Coronária/patologia , Reestenose Coronária/prevenção & controle , Matriz Extracelular/patologia , Piridonas/uso terapêutico , Animais , Lesões das Artérias Carótidas/patologia , Lesões das Artérias Carótidas/prevenção & controle , Artéria Carótida Primitiva/efeitos dos fármacos , Artéria Carótida Primitiva/patologia , Matriz Extracelular/efeitos dos fármacos , Masculino , Piridonas/farmacologia , Ratos , Ratos Wistar
16.
Circ Heart Fail ; 3(1): 89-96, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19996415

RESUMO

BACKGROUND: The aim of this study was to investigate the clinical outcome 2 years after intracoronary administration of autologous progenitor cells in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: Using a double-blind, placebo-controlled, multicenter trial design, we randomized 204 patients with successfully reperfused AMI to receive intracoronary infusion of bone marrow-derived progenitor cells (BMC) or placebo medium into the infarct artery 3 to 7 days after successful infarct reperfusion therapy. At 2 years, the cumulative end point of death, myocardial infarction, or necessity for revascularization was significantly reduced in the BMC group compared with placebo (hazard ratio, 0.58; 95% CI, 0.36 to 0.94; P=0.025). Likewise, the combined end point death and recurrence of myocardial infarction and rehospitalization for heart failure, reflecting progression toward heart failure, was significantly reduced in the BMC group (hazard ratio, 0.26; 95% CI, 0.085 to 0.77; P=0.015). Intracoronary administration of BMC remained a significant predictor of a favorable clinical outcome by Cox regression analysis when adjusted for classical predictors of poor outcome after AMI. There was no evidence of increased restenosis or atherosclerotic disease progression after BMC therapy nor any evidence of increased ventricular arrhythmias or neoplasms. In addition, regional left ventricular contractility of infarcted segments, as assessed by MRI in a subgroup of patients at 2-year follow-up, was significantly higher in the BMC group compared with the placebo group (P<0.001). CONCLUSIONS: Intracoronary administration of BMC is associated with a significant reduction of the occurrence of major adverse cardiovascular events maintained for 2 years after AMI. Moreover, functional improvements after BMC therapy may persist for at least 2 years. Larger studies focusing on clinical event rates are warranted to confirm the effects of BMC administration on mortality and progression of heart failure in patients with AMIs. Clinical Trial Registration- clinicaltrials.gov. Identifier: NCT00279175.


Assuntos
Infarto do Miocárdio/cirurgia , Transplante de Células-Tronco , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Vasos Coronários , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco , Resultado do Tratamento
17.
JACC Cardiovasc Interv ; 2(11): 1047-54, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19926042

RESUMO

OBJECTIVES: The aim of the study was to evaluate the safety, feasibility, and procedural variables by the transradial approach compared with the transfemoral access in a standard population of patients undergoing coronary catheterization. BACKGROUND: Coronary catheterization is usually performed via the transfemoral approach. Transradial access may offer some advantages in comparison with transfemoral access especially under conditions of aggressive anticoagulation and antiplatelet treatment. METHODS: Between July 2006 and January 2008, a total of 1,024 patients undergoing coronary catheterization were randomly assigned to the transradial or transfemoral approach. Patients with an abnormal Allen's test, history of coronary artery bypass surgery, simultaneous right heart catheterization, chronic renal insufficiency, or known difficulties with the radial or femoral access were excluded. RESULTS: Successful catheterization was achieved in 494 of 512 patients (96.5%) in the transradial and in 511 of 512 patients (99.8%) in the transfemoral group (p < 0.0001). Median procedural duration (37.0 min, interquartile range [IQR] 19.6 to 49.1 min vs. 40.2 min, IQR 24.3 to 50.8 min; p = 0.046) and median dose area product (38.2 Gycm(2), IQR 20.4 to 48.5 Gycm(2) vs. 41.9 Gycm(2), IQR 22.6 to 52.2 Gycm(2); p = 0.034) were significantly lower in the transfemoral group compared with the transradial access group. A median amount of contrast agent was similar among both groups. Vascular access site complications were higher in the transfemoral group (3.71%) than in the transradial group (0.58%; p = 0.0008) CONCLUSIONS: The findings of the present study show that transradial coronary angiography and angioplasty are safe, feasible, and effective with similar results to those of the transfemoral approach. However, procedural duration and radiation exposure are higher using the transradial access. In contrast to the transfemoral route, the rate of major vascular complications was negligible using the transradial approach.


Assuntos
Angioplastia Coronária com Balão/métodos , Cateterismo Cardíaco/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Artéria Femoral , Artéria Radial , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Anticoagulantes/uso terapêutico , Cateterismo Cardíaco/efeitos adversos , Angiografia Coronária/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Prospectivos , Radiografia Intervencionista , Fatores de Tempo , Resultado do Tratamento
18.
Circ Res ; 104(10): 1192-200, 2009 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-19372464

RESUMO

3-Deazaadenosine (c3Ado) is a potent inhibitor of S-adenosylhomocysteine hydrolase, which regulates cellular methyltransferase activity. In the present study, we sought to determine the effect of c3Ado on vascular smooth muscle cell (VSMC) function and neointima formation in vivo. c3Ado dose-dependently prevented the proliferation and migration of human coronary VSMCs in vitro. This was accompanied by an increased expression of the cyclin-dependent kinase inhibitors p21(WAF1/Cip1), p27(Kip1), a decreased expression of G(1)/S phase cyclins, and a lack of retinoblastoma protein hyperphosphorylation. In accordance with these findings, fluorescence-activated cell-sorting analysis of propidium iodide-stained cells indicated a cell cycle arrest in the G(0)/G(1) phase. Importantly, c3Ado did not affect the number of viable (trypan blue exclusion) or apoptotic cells (TUNEL). Mechanistically, c3Ado prevented FCS-induced Ras carboxyl methylation and membrane translocation and activity by inhibiting isoprenylcysteine carboxyl methyltransferase and reduced FCS-induced extracellular signal-regulated kinase (ERK)1/2 and Akt phosphorylation in a dose-dependent manner. Conversely, rescuing signal transduction by overexpression of a constitutive active Ras mutant abrogated c3Ado's effect on proliferation. For in vivo studies, the femoral artery of C57BL/6 mice was dilated and mice were fed a diet containing 150 microg of c3Ado per day. c3Ado prevented dilation-induced Ras activation, as well as ERK1/2 and Akt phosphorylation in vivo. At day 21, VSMC proliferation (proliferating-cell nuclear antigen [PCNA]-positive cells), as well as the neointima/media ratio (0.7+/-0.2 versus 1.6+/-0.4; P<0.05) were significantly reduced, without any changes in the number of apoptotic cells. Our data indicate that c3Ado interferes with Ras methylation and function and thereby with mitogenic activation of ERK1/2 and Akt, preventing VSMC cell cycle entry and proliferation and neointima formation in vivo. Thus, therapeutic inhibition of S-adenosylhomocysteine hydrolase by c3Ado may represent a save and effective novel approach to prevent vascular proliferative disease.


Assuntos
Proliferação de Células/efeitos dos fármacos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais/fisiologia , Tubercidina/farmacologia , Adenosil-Homocisteinase/antagonistas & inibidores , Animais , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Vasos Coronários/citologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Relação Dose-Resposta a Droga , Humanos , Masculino , Metilação/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo
19.
Am Heart J ; 157(3): 541-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19249426

RESUMO

BACKGROUND: Serial cardiac magnetic resonance imaging (CMR) is the reference standard for evaluating left ventricular function, wall motion, and infarct size in patients with acute myocardial infarction, as well as remodeling during follow-up. The cardiac CMR substudy of the randomized multicenter REPAIR-AMI trial (Reinfusion of Enriched Progenitor cells And Infarct Remodeling in Acute Myocardial Infarction study) aimed at gaining insight into postinfarction left ventricular remodeling processes. METHODS: Consecutive patients with ST-segment elevation myocardial infarction and primary percutaneous coronary intervention were enrolled (n = 204) and randomly assigned to either stem cell therapy (bone marrow-derived progenitor cells [BMC]) or placebo after bone marrow aspiration. In the magnetic resonance imaging substudy, 54 patients completed serial CMR (baseline, 4 and 12 months, respectively) after enrollment (27 BMC, 27 placebo). Image analysis was performed at a central core laboratory. RESULTS: There were no significant differences between the 2 groups with respect to global ejection fraction (EF), end-diastolic volume (EDV), and end-systolic volume (ESV) at baseline. At 12 months, the treatment effect of BMC infusion on EF amounted to 2.8 absolute percentage points (P = .26), the progression of EDV at 12 months was less in the BMC group (treatment effect 14 mL, P = .12), and unlike placebo, ESV did not increase (absolute treatment effect 13 mL, P = .08), respectively. In patients with a baseline EF < median (EF < or = 48.9%), BMC administration was associated with a significantly improved EF (+6.6%, P = .01), reduced EDV increase (treatment effect 29.1 mL, P = .02), and abrogation of ESV increase (treatment effect 29.4 mL, P = .01) after 12 months, respectively. CONCLUSION: Intracoronary administration of BMC additionally improved left ventricular function in patients with impaired left ventricular function after ST-segment elevation myocardial infarction despite optimal "state-of-the-art" reperfusion and pharmacologic treatment on 1-year follow-up and beneficially interfered with adverse postinfarction left ventricular remodeling.


Assuntos
Infarto do Miocárdio/cirurgia , Transplante de Células-Tronco , Função Ventricular Esquerda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Volume Sistólico , Remodelação Ventricular/fisiologia , Adulto Jovem
20.
Herz ; 34(1): 39-54, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19214408

RESUMO

In Western countries, chronic coronary artery disease (CAD) has a prevalence of 3-4%. The aims of treatment of chronic CAD are (1) improvement of quality of life by preventing anginal pain, by maintaining exercise capability, and by reducing anxiety; (2) decrease of cardiovascular morbidity, especially by avoiding myocardial infarction and development of heart failure; (3) reduction of mortality. These goals can be achieved by (a) cardiovascular risk reduction, especially management of risk factors, (b) optimal medical therapy, (c) coronary revascularization, (d) periods of rehabilitation, and (e) outpatient long-term observation and treatment. The patient has a good chance to improve the natural course of his disease by changing his lifestyle. In this regard, physical exercise, weight reduction and smoking cessation have to be mentioned first. Furthermore, the cardiovascular risk may significantly be diminished by adequate treatment of hyperlipoproteinemia: lowering of plasma LDL cholesterol levels in patients with chronic CAD is associated with a retarded progression of atherosclerosis as well as a decrease of cardiovascular events by 30-40% and lower mortality (by up to 34%). In patients with CAD and/or type 2 diabetes, statin therapy leads to a significant improvement of prognosis independent of the basal value of LDL cholesterol. Improved diet and adequate medical therapy may also result in diminished cardiovascular risk. By means of physical activity, mortality and morbidity of CAD can also be significantly reduced. The antianginal medication in patients with chronic CAD consists of nitrates, beta-blockers, and calcium channel blockers. In order to prevent myocardial infarction and death (secondary prevention), antiplatelet agents, renin-angiotensin-aldosterone system blockers, as well as cholesterol-lowering drugs are applied. In this paper, the guidelines of the American College of Cardiology/American Heart Association, the European Society of Cardiology and the NVL-KHK (German) guidelines regarding prevention, medical therapy and coronary artery revascularization procedures are summarized. Do the guidelines reflect daily practice? To answer this question, the following topics are discussed: (1) Management of risk factors with respect to available guidelines, (2) missing evidence from randomized controlled trials for medical therapy options widely used in clinical practice, (3) guideline-compliant use or underuse of diagnostic assessment, medical therapy and revascularization procedures, (4) gender bias in indications for percutaneous coronary interventions and in the use of investigations/evidence-based medical therapy, and (5) nonadherence to existing guidelines.


Assuntos
Cardiologia/normas , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/prevenção & controle , Fidelidade a Diretrizes , Guias de Prática Clínica como Assunto , Medicina Preventiva/normas , Alemanha , Humanos , Padrões de Prática Médica/normas
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