Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Surg Today ; 46(4): 393-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25935205

RESUMEN

In this review article, we describe several topics, including the sandwich technique, the transatrial re-endocardialization technique, the limited apical left ventriculotomy approach and device closure. The sandwich technique was introduced for the closure of muscular ventricular septal defects (VSD) by sandwiching the septum between two felt patches placed in the left and right ventricle. This technique requires neither the transection of muscular trabeculae nor ventriculotomy. Although the sandwich technique has resulted in the improvement of surgical outcomes, cases of postoperative cardiac dysfunction have been reported. Multiple smaller VSDs have been closed with transatrial re-endocardialization. Septal dysfunction may be avoided through this technique, in which the septal trabeculae are approximated in two layers of superficial, endocardial running sutures. Recently, a number of reports have recommended a limited apical left ventriculotomy approach. With this technique, a much shorter incision of around 1 cm at the apex of the left ventricle may be sufficient for achieving the complete closure of apical muscular VSDs. The transcatheter or perventricular device closure of muscular VSDs has increasingly been performed with good results. Although favorable early and mid-term results of device closure have been reported, this method is not always safer or less invasive than surgical closure. Long-term evaluations should be performed to determine whether the right and left ventricular functions are affected by treatment with relatively large devices in the heart.


Asunto(s)
Anomalías Múltiples/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Defectos del Tabique Interventricular/cirugía , Procedimientos Quirúrgicos Cardíacos/tendencias , Humanos , Resultado del Tratamiento
2.
Kyobu Geka ; 69(7): 537-40, 2016 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-27365067

RESUMEN

Isolated pulmonary valve endocarditis is an extremely rare clinical condition. Here, we report a case of pulmonary valve endocarditis caused by methicillin-resistant Staphylococcus aureus (MRSA). An 84-year-old man with a history of aortic regurgitation and patent foramen ovale was admitted to our hospital due to fever of unknown origin for 4 weeks' duration. MRSA was detected in his blood cultures. Transthoracic echocardiography demonstrated a mobile vegetation attached to the pulmonary valve, moderate to severe aortic regurgitation, and patent foramen ovale with left-to-right shunt. After 30-days' treatment with vancomycin, gentamicin and rifampicin, he defervesced and blood cultures became negative. At surgery, a large vegetation was still attached to the pulmonary valve, but the leaflets remained with minimum damage. Aortic valve replacement, direct closure of the patent foramen ovale, and simple resection of the vegetation were performed. The postoperative course was uneventful.


Asunto(s)
Insuficiencia de la Válvula Aórtica/complicaciones , Endocarditis/microbiología , Foramen Oval Permeable/complicaciones , Enfermedades de las Válvulas Cardíacas/microbiología , Staphylococcus aureus Resistente a Meticilina , Válvula Pulmonar , Infecciones Estafilocócicas , Anciano de 80 o más Años , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Ecocardiografía , Endocarditis/diagnóstico por imagen , Endocarditis/cirugía , Foramen Oval Permeable/diagnóstico por imagen , Foramen Oval Permeable/cirugía , Enfermedades de las Válvulas Cardíacas/diagnóstico , Enfermedades de las Válvulas Cardíacas/etiología , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
3.
Crit Care Med ; 43(11): e508-20, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26468714

RESUMEN

OBJECTIVES: The calcium sensitizer levosimendan is used in treatment of decompensated heart failure and may also exhibit anti-inflammatory properties. We examined whether treatment with levosimendan is substantially beneficial in mice with cecal ligation and puncture-induced polymicrobial sepsis, and its arbitration mechanism was explored in the mouse macrophage cell line RAW264.7. DESIGN: Laboratory and animal/cell research. SETTING: University research laboratory. SUBJECTS: BALB/c mice (8-10 wk old) and mouse macrophage cell line RAW264.7 cells. INTERVENTIONS: Levosimendan (0.5 µg/kg/min) was administered to mice through an osmotic pump that was implanted into the peritoneal cavity immediately following surgery. In RAW264.7 cells, levosimendan was added to the culture medium 30 minutes before lipopolysaccharide. MEASUREMENTS AND MAIN RESULTS: When levosimendan was continuously administered to cecal ligation and puncture-induced septic mice, a significant improvement of left ventricular function was found without any change in heart rate, and hypotension was significantly mitigated. Furthermore, levosimendan conferred substantial protection against sepsis-associated inflammation in mice, as indicated by reduced lung injury and decreased blood proinflammatory and chemotactic cytokine levels. These beneficial effects of levosimendan led to a significant improvement of survival in mice after cecal ligation and puncture. In endotoxin-stimulated RAW264.7 macrophages, treatment with levosimendan and pimobendan suppressed overproduction of proinflammatory and chemotactic cytokines. Levosimendan and pimobendan were without effect on activation of the nuclear factor-κB, mitogen-activated protein kinase, and Akt pathways. Instead, levosimendan and pimobendan prevented high mobility group box 1 release from the nucleus to the extracellular space in macrophages. This was associated with inhibition of the Rho kinase signaling pathway. The elevated serum high mobility group box 1 levels in cecal ligation and puncture-induced septic mice were also inhibited by continued administration of levosimendan and pimobendan. CONCLUSIONS: We define a novel mechanism for the anti-inflammatory action of levosimendan and suggest that the pharmacological profiles of levosimendan as both an inotrope and an anti-inflammatory agent could contribute to its clinical benefit in patients with sepsis with heart problems.


Asunto(s)
Antiinflamatorios/farmacología , Citocinas/metabolismo , Hidrazonas/farmacología , Macrófagos/efectos de los fármacos , Piridazinas/farmacología , Sepsis/tratamiento farmacológico , Sepsis/patología , Animales , Biopsia con Aguja , Western Blotting , Ciego/cirugía , Células Cultivadas , Citocinas/efectos de los fármacos , Modelos Animales de Enfermedad , Ecocardiografía/métodos , Ensayo de Inmunoadsorción Enzimática , Inmunohistoquímica , Inyecciones Intravenosas , Ligadura/métodos , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa , Valores de Referencia , Sepsis/mortalidad , Simendán , Estadísticas no Paramétricas , Tasa de Supervivencia
4.
J Surg Res ; 193(2): 874-87, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25291964

RESUMEN

BACKGROUND: Cardiac dysfunction is a frequent and severe complication of septic shock and contributes to the high mortality of sepsis. Although several mechanisms have been suspected to be responsible for sepsis-associated cardiac dysfunction, the precise cause(s) remains unclear to date. MATERIALS AND METHODS: We tested the hypothesis that cardiac fibroblasts may play a critical role as a disease modifier involved in sepsis-associated cardiac dysfunction. Human cardiac fibroblasts (HCFs) cultured in vitro were exposed to lipopolysaccharide (LPS). Changes in cardiac morphology and function were assessed in mice with cecal ligation and puncture-induced sepsis. RESULTS: In LPS-stimulated HCFs, messenger RNA and protein levels of proinflammatory molecules, including tumor necrosis factor-α, interleukin-1ß, interleukin-6, and monocyte chemoattractant protein-1, were strikingly upregulated. LPS also increased expression and activity of matrix metalloproteinase (MMP)-9, but not MMP-2. LPS-induced expression of α-smooth muscle actin, a classical marker for myoblast differentiation, which was abrogated when MMP-9 small interfering RNA was transfected into HCFs. High gene expression levels of proinflammatory cytokines and MMP-9 were observed in the heart tissues of cecal ligation and puncture-induced septic mice. Histology sections of the hearts from septic mice showed perivascular and interstitial cardiac fibrosis, and echocardiography demonstrated that septic mice had profound cardiac dysfunction. The broad-spectrum MMP inhibitor ONO-4817 significantly alleviated these histologic and functional changes during the acute phase. CONCLUSIONS: We suggest that cardiac fibroblasts are of pathogenetic importance in inflammation and fibrosis in the heart during sepsis, leading to cardiac dysfunction that would affect the outcome of sepsis syndrome.


Asunto(s)
Fibroblastos/fisiología , Corazón/fisiopatología , Choque Séptico/fisiopatología , Actinas/metabolismo , Animales , Células Cultivadas , Citocinas/metabolismo , Fibrosis , Historia Antigua , Humanos , Lipopolisacáridos , Masculino , Metaloproteinasas de la Matriz/metabolismo , Ratones Endogámicos BALB C , Miocardio/patología , FN-kappa B/metabolismo , Éteres Fenílicos , Choque Séptico/patología
5.
J Pharmacol Exp Ther ; 349(2): 199-208, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24570070

RESUMEN

G protein-coupled receptor kinase 2 (GRK2) participates together with ß-arrestins in the regulation of G protein-coupled receptor signaling, but emerging evidence suggests that GRK2 can interact with a growing number of proteins involved in signaling mediated by other membrane receptor families under various pathologic conditions. We tested the hypothesis that GRK2 may be an important contributor to vascular endothelial dysfunction in diabetes. Human umbilical venous endothelial cells (HUVECs) were exposed to high glucose and high insulin (HG/HI) to mimic insulin-resistant diabetic conditions. GRK2 expression and membrane translocation were up-regulated under HG/HI conditions. HG/HI did not modify activation of Akt or endothelial nitric-oxide synthase (eNOS), but GRK2 inhibitor or small interfering RNA (siRNA) resulted in an increase in Akt and eNOS activation in HUVECs exposed to HG/HI. Extracellular signal-regulated kinase 1/2 (ERK1/2) activation was increased after exposure to HG/HI, which was prevented by GRK2 inhibitor or siRNA. ERK1/2-mediated GRK2 phosphorylation at Ser-670 confirmed that ERK1/2 participated in a negative feedback regulatory loop. In human embryonic kidney 293T cells that overexpressed GRK2, Akt activity was unchanged, whereas ERK1/2 activity was raised. The effect of GRK inhibitor treatment on Akt/eNOS signaling was associated with membrane translocation of ß-arrestin 2. The experiments with ß-arrestin 2 siRNA showed that ß-arrestin 2 may act as a positive modulator of Akt/eNOS signaling. Our studies reveal that GRK2, which is up-regulated by HG/HI, leads to a tonic inhibition of the insulin Akt/eNOS pathway in endothelial cells. We provide new insights into the pathogenesis of diabetes-associated vascular endothelial dysfunction.


Asunto(s)
Endotelio Vascular/metabolismo , Quinasa 2 del Receptor Acoplado a Proteína-G/antagonistas & inhibidores , Glucosa/metabolismo , Insulina/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Arrestinas/metabolismo , Diabetes Mellitus/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Quinasa 2 del Receptor Acoplado a Proteína-G/genética , Quinasa 2 del Receptor Acoplado a Proteína-G/metabolismo , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Resistencia a la Insulina , Nitrofuranos/farmacología , Transporte de Proteínas , ARN Interferente Pequeño/genética , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Compuestos de Vinilo/farmacología , Arrestina beta 2 , beta-Arrestinas
6.
Surg Today ; 44(12): 2221-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24633930

RESUMEN

Surgical correction of total anomalous pulmonary venous connection (TAPVC) remains a challenge, with reported early mortality rates of up to 20%. In this review article, we describe several topics, including surgery for neonates, diagnoses with multidetector computed tomography (MDCT), and primary sutureless repair. Several studies have reported mortality rates of around 10%, and demonstrated unchanged hospital mortality in neonates, despite improvement of the overall mortality of cohorts including older patients. Previous reports identified a low body weight at the time of the operation, preoperative pulmonary venous obstruction (PVO), and a prolonged cardiopulmonary bypass time as risk factors for hospital mortality. With the development of new technologies, MDCT has become a good diagnostic modality for use in the pre- and post-operative evaluation. MDCT delineates the drainage site of the vertical vein and the atypical vessel into the systemic vein, and it can also evaluate the existence of obstruction in the vertical vein. Following favorable experiences with post-repair PVO, the indications for sutureless repair as a primary operation have been expanded for infants, including those at risk of developing PVO after the repair of TAPVC. Primary sutureless repair has proven especially useful for difficult patient groups, such as those with congenital PVO, infracardiac TAPVC with small pulmonary veins, or mixed-type TAPVC.


Asunto(s)
Venas Pulmonares/anomalías , Venas Pulmonares/cirugía , Procedimientos Quirúrgicos Vasculares/métodos , Puente Cardiopulmonar , Mortalidad Hospitalaria , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Tomografía Computarizada Multidetector , Tempo Operativo , Venas Pulmonares/diagnóstico por imagen , Enfermedad Veno-Oclusiva Pulmonar , Factores de Riesgo , Técnicas de Sutura , Resultado del Tratamiento
7.
Ann Vasc Dis ; 15(3): 186-192, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36310737

RESUMEN

Objectives: We investigated the relationship between plasma lipoprotein(a) [Lp(a)] level and long-term prognosis, cardiovascular events, or pure leg events (LE) in patients with peripheral arterial disease (PAD). Materials and Methods: We prospectively enrolled 1104 PAD patients. The endpoints were LE, cerebrovascular- or cardiovascular-related death (CVRD), all-cause death (ACD), and major adverse cardiovascular events (MACE). Results: The incidences of LE, CVRD, ACD, and MACE were correlated with Lp(a) level (P<0.05). Lp(a) was positively correlated with low-density lipoprotein cholesterol and C-reactive protein (CRP) and negatively correlated with estimated glomerular filtration rate (eGFR). In the Cox multivariate regression analysis, high Lp(a), CRP, age, low ankle-brachial pressure index (ABI), eGFR, albumin, critical limb ischemia (CLI), cerebrovascular disease (CVD), and diabetes were associated with LE; high Lp(a), age, CRP, low ABI, body mass index, eGFR, albumin, CLI, coronary heart disease (CHD), CVD, and diabetes were associated with CVRD; high Lp(a), CRP, age, low ABI, eGFR, albumin, CLI, and CVD were associated with ACD; and high Lp(a), CRP, age, low eGFR, albumin, CLI, CHD, and diabetes were associated with MACE (P<0.05). Statins improved all endpoints (P<0.01). Conclusion: Lp(a) was a significant residual risk factor for LE, CVRD, ACD, and MACE in PAD patients.

8.
Kyobu Geka ; 64(12): 1056-60, 2011 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-22187864

RESUMEN

A 78-year-old man referred to our hospital with the chief complaints of anorexia, general malaise, rash, and weight loss. Laboratory examination revealed pancytopenia, hyperglobulinemia, generalized adenopathy, and multiple pulmonary nodules. Video-assisted thoracic surgery (VATS) was performed to diagnose pulmonary nodules. After operation, it was difficult to achieve hemostasis for a while. Finally, the patient was diagnosed as pulmonary cryptococcosis and Evans syndrome.


Asunto(s)
Anemia Hemolítica Autoinmune/diagnóstico , Criptococosis/diagnóstico , Enfermedades Pulmonares Fúngicas/diagnóstico , Pulmón/patología , Nódulos Pulmonares Múltiples/diagnóstico , Púrpura Trombocitopénica Idiopática/diagnóstico , Cirugía Torácica Asistida por Video , Anciano , Humanos , Masculino
9.
Int Angiol ; 40(6): 520-527, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34313412

RESUMEN

BACKGROUND: Brain natriuretic peptide (BNP) is introduced as a predictor of the degree of ventricular dysfunction and is associated with mortality. There are limited reports on the relationship of BNP with long-term all-cause death (AD) and cardiovascular or limb events in peripheral artery disease (PAD). We examined the relationship between BNP level and these events in PAD patients. METHODS: We performed a prospective cohort study in 938 PAD patients. The patients were divided into four groups based on BNP levels with median (interquartile range): Q1: ≤20.4; Q2: 20.5-42.8; Q3: 42.9-103.4; and Q4: ≥103.5 pg/mL. The endpoints were AD, freedom from major adverse cardiovascular events (MACE), and MACE plus limb events (MALE). RESULTS: The median follow-up time was 65 months. There were 383 deaths (40.8%) during follow-up period. AD depended on BNP levels (P<0.01), with 5-year freedom from AD rates of Q1: 94%, Q2: 84%, Q3: 69%, and Q4: 55%. The Kaplan-Meier estimates of freedom from AD, MACE, and MALE had significant differences among Q1- Q4 groups (P<0.001). In multiple regression analysis, BNP had significant negative correlations with eGFR, serum albumin, and BMI and positive correlations with diabetes (P<0.05). In Cox multivariate analysis, higher BNP, age, CRP, D-dimer, lower BMI, ABI, serum albumin, and eGFR were related to AD; and higher BNP, age, lower ABI, serum albumin, CAD, and DM were related to MACE and MALE (P<0.05). Statins improved AD, MACE, and MALE (P<0.01). CONCLUSIONS: BNP was a promising biomarker for AD, MACE, and MALE in patients with PAD.


Asunto(s)
Péptido Natriurético Encefálico , Enfermedad Arterial Periférica , Biomarcadores , Humanos , Esperanza de Vida , Enfermedad Arterial Periférica/diagnóstico , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos
10.
Ann Vasc Dis ; 14(3): 236-243, 2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34707745

RESUMEN

Objective: This study aimed to examine the relationship between microalbuminuria and long-term life expectancy or limb events in patients with peripheral arterial disease (PAD). Materials and Methods: A prospective cohort study was performed in 714 patients with PAD. The primary outcomes were cardiovascular or cerebrovascular death (CCVD) and all-cause death (AD), and secondary outcomes were major adverse cardiovascular events (MACE) and cardiovascular and/or limb events (CVLE). Results: The 5, 10, and 15 year survival rates were 82.4%, 53.1%, and 33.0%, respectively. The prevalence of patients with increased microalbuminuria was 39.2%. Higher microalbuminuria, age, C-reactive protein (CRP), lower serum albumin, estimated glomerular filtration rate (eGFR), ankle-brachial pressure index (ABI), diabetes, cerebral infarction, and coronary heart disease (CHD) were associated with CCVD; higher microalbuminuria, age, CRP, D-dimer, lower serum albumin, eGFR, and critical limb ischemia were related to AD; higher microalbuminuria, age, CRP, lower serum albumin, ABI, diabetes, and CHD were related to MACE; higher microalbuminuria, age, lower ABI, cerebral infarction, and CHD were related to CVLE in Cox multivariate analyses (p<0.05). Statins reduced CCVD, AD, MACE, and CVLE (p<0.001). Conclusion: Higher microalbuminuria was a significant predictor for CCVD, AD, MACE, and CVLE in PAD patients.

11.
Immunobiology ; 223(12): 777-785, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30115376

RESUMEN

Pulmonary endothelial injury is central in the pathogenesis of acute lung injury (ALI). The MAPK signaling cascades are generally thought to be involved in the molecular mechanism underlying the ALI development, but their roles in pulmonary endothelial injury is poorly understood. We thus examined the involvement of the MAPK family member in inflammatory responses of human pulmonary microvascular endothelial cells (HPMVECs) stimulated with LPS and IFN-γ. HPMVECs were found to exhibit the upregulation of expression of Toll-like receptor 4 by IFN-γ, resulting in potentiation of inflammatory cytokine release by LPS stimulation. All MAPKs, ERK1/2, JNK, and p38, were activated by simultaneous stimulation with LPS/IFN-γ. JNK activation in cells stimulated with LPS/IFN-γ was significantly potentiated by the two different p38 inhibitors, SB203580 and RWJ67657, suggesting the negative regulation of JNK activation by p38 in HPMVECs. The mRNA and protein expression levels of ICAM-1 were eliminated by the JNK inhibitor, suggesting that ICAM-1 expression is positively regulated by JNK. The p38 inhibitor significantly enhanced ICAM-1 expression. ERK1/2 activation was not responsible for the LPS/IFN-γ-induced ICAM-1 upregulation in HPMVECs. THP-1 monocyte adhesion to HPMVECs under LPS/IFN-γ stimulation was inhibited by the JNK inhibitor and enhanced by the p38 inhibitor. We conclude that, in HPMVECs stimulated with LPS/IFN-γ, JNK mediates ICAM-1 expression that can facilitate leukocyte adherence and transmigration, while p38 MAPK negatively regulates the upregulation of ICAM-1 through inhibition of JNK activation.


Asunto(s)
Células Endoteliales/metabolismo , Interferón gamma/metabolismo , Lipopolisacáridos/inmunología , Pulmón/inmunología , Pulmón/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Biomarcadores , Adhesión Celular/inmunología , Línea Celular , Citocinas/inmunología , Citocinas/metabolismo , Células Endoteliales/efectos de los fármacos , Expresión Génica , Humanos , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Interferón gamma/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Neumonía/etiología , Neumonía/metabolismo , Neumonía/patología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
12.
Ann Vasc Dis ; 9(3): 223-227, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27738468

RESUMEN

Right aortic arch with aberrant left subclavian artery and Kommerell diverticulum are rare anomalies. A 42-year-old man was referred with sudden-onset chest pain. Enhanced computed tomography (CT) showed a right aortic arch with early thrombosed acute type A aortic dissection and an aberrant left subclavian artery arising from a Kommerell diverticulum. Medical therapy was instituted; however, follow-up CT revealed an ulcer-like projection. The patient was managed with a two-stage hybrid procedure comprising total arch replacement and endovascular repair and experienced no postoperative complications. Two-stage hybrid repair is a safe and effective surgical option for rare complex aortic anomalies.

13.
Ann Vasc Dis ; 8(4): 321-3, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26730259

RESUMEN

Acute aortic occlusion is a catastrophic event requiring early recognition and intervention. The patient was diagnosed type B aortic dissection. He became anuric on the sixth day of illness and the femoral artery pulse was not palpable. Therefore the patient was conveyed to our hospital. During transfer, his blood pressure was suddenly elevated and later he was in cardiopulmonary arrest. After cardiopulmonary resuscitation, the heart resumed beating in several minutes. Acute dynamic obstruction was regarded as a cause of the cardiac arrest. A thoracic endovascular aortic repair was performed urgently. His postoperative period was uneventful and the patient was discharged without problems.

14.
Vascul Pharmacol ; 70: 55-65, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25869503

RESUMEN

Vascular endothelial cells can absorb higher radiation doses than any other tissue in the body, and post-radiation impaired endothelial nitric oxide synthase (eNOS) function may be developed as a potential contributor to the pathogenesis of vascular injury. In this study, we investigated early alterations of eNOS signaling in human umbilical venous endothelial cells (HUVECs) exposed to X-ray radiation. We found that ionizing radiation increased eNOS phosphorylation at Ser-1177 and dephosphorylation at Thr-495 in HUVECs in a dose-dependent (≤ 20 Gy) and time-dependent (6-72 h) manner. The total expression levels of eNOS were unchanged by radiation. Although a transient but significant increase in extracellular signal-regulated protein kinase 1/2 (ERK1/2) phosphorylation and a biphasic decline in Akt phosphorylation were observed after irradiation, these inhibitors were without effect on the radiation-induced changes in eNOS phosphorylation. There was an increase in protein kinase C-ßII (PKC-ßII) expression and the ablation of PKC-ßII by small interfering RNA (siRNA) negated the radiation effect on the two eNOS phosphorylation events. Furthermore, when the radiation-induced increase in reactive oxygen species (ROS) generation was prevented by the anti-oxidant N-acetyl-L-cysteine, eNOS Ser-1177 phosphorylation and Thr-495 dephosphorylation in irradiated HUVECs were significantly reduced. However, transfection of PKC-ß siRNA did not alter ROS production after irradiation, and NAC failed to block the radiation-induced increase in PKC-ßII expression. Taken together, our results suggest that ionizing radiation-induced eNOS activation in human vascular endothelial cells is attributed to both the up-regulation of PKC-ßII and the increase in ROS generation which were independent of each other.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana/efectos de la radiación , Óxido Nítrico Sintasa de Tipo III/metabolismo , Proteína Quinasa C beta/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/farmacología , Células Cultivadas , Relación Dosis-Respuesta en la Radiación , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/enzimología , Humanos , Fosforilación , Proteína Quinasa C beta/antagonistas & inhibidores , Proteína Quinasa C beta/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Transfección , Regulación hacia Arriba
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA