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1.
Eur Respir J ; 58(2)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33542050

RESUMO

RATIONALE: Nontuberculous mycobacteria (NTM) are environmental mycobacteria that can cause a chronic progressive lung disease. Although epidemiological data indicate potential genetic predisposition, its nature remains unclear. OBJECTIVES: We aimed to identify host susceptibility loci for Mycobacterium avium complex (MAC), the most common NTM pathogen. METHODS: This genome-wide association study (GWAS) was conducted in Japanese patients with pulmonary MAC and healthy controls, followed by genotyping of candidate single-nucleotide polymorphisms (SNPs) in another Japanese cohort. For verification by Korean and European ancestry, we performed SNP genotyping. RESULTS: The GWAS discovery set included 475 pulmonary MAC cases and 417 controls. Both GWAS and replication analysis of 591 pulmonary MAC cases and 718 controls revealed the strongest association with chromosome 16p21, particularly with rs109592 (p=1.64×10-13, OR 0.54), which is in an intronic region of the calcineurin-like EF-hand protein 2 (CHP2). Expression quantitative trait loci analysis demonstrated an association with lung CHP2 expression. CHP2 was expressed in the lung tissue in pulmonary MAC disease. This SNP was associated with the nodular bronchiectasis subtype. Additionally, this SNP was significantly associated with the disease in patients of Korean (p=2.18×10-12, OR 0.54) and European (p=5.12×10-03, OR 0.63) ancestry. CONCLUSIONS: We identified rs109592 in the CHP2 locus as a susceptibility marker for pulmonary MAC disease.


Assuntos
Pneumopatias , Infecções por Mycobacterium não Tuberculosas , Infecção por Mycobacterium avium-intracellulare , Estudo de Associação Genômica Ampla , Humanos , Infecções por Mycobacterium não Tuberculosas/genética , Complexo Mycobacterium avium , Micobactérias não Tuberculosas
2.
Biol Pharm Bull ; 41(5): 754-760, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29709912

RESUMO

The aim of the present study was to investigate the influence of polysorbate 60 (Tween 60) on the development of morin-loaded nanoemulsions to improve the oral bioavailability of morin. Nanoemulsions were prepared using Tween 60 and polyvinyl alcohol (PVA) as emulsifiers, and medium chain triglycerides (MCT) as the lipid base. Low-saponification-degree PVA (LL-810) was also added to stabilize dispersed droplets. MCT-LL810 nanoemulsion containing LL-810 was prepared with a reduced amount of Tween 60. However, the area under the blood concentration-time curve (AUC) of MCT-LL810 (0.18) nanoemulsion containing a small amount of Tween 60 did not increase because the absorption of morin was limited by P-glycoprotein (P-gp)-mediated efflux. MCT-LL810 (0.24) nanoemulsion containing a large amount of Tween 60 showed the highest AUC, dispersed droplets containing Tween 60 may have been transported into epithelial cells in the small intestine, and P-gp transport activity appeared to be suppressed by permeated Tween 60. Based on the plasma concentration profile, dispersed droplets in MCT-LL810 (0.24) nanoemulsion permeated more rapidly through the mucus layer and the intestinal membrane than MCT (0.24) nanoemulsion without LL-810. In conclusion, a novel feature of Tween 60 incorporated into the dispersed droplets of a nanoemulsion interacting with P-gp was demonstrated herein. Dispersed droplets in MCT-LL810 (0.24) nanoemulsion containing LL-810 permeated rapidly through the mucus layer and intestinal membrane, and Tween 60 incorporated in dispersed droplets interacted with P-gp-mediated efflux, increasing the bioavailability of morin.


Assuntos
Flavonoides , Nanopartículas , Polissorbatos , Álcool de Polivinil , Administração Oral , Animais , Disponibilidade Biológica , Composição de Medicamentos , Liberação Controlada de Fármacos , Emulsões , Flavonoides/administração & dosagem , Flavonoides/sangue , Flavonoides/química , Flavonoides/farmacocinética , Masculino , Camundongos Endogâmicos ICR , Nanopartículas/administração & dosagem , Nanopartículas/química , Polissorbatos/administração & dosagem , Polissorbatos/química , Polissorbatos/farmacocinética , Álcool de Polivinil/administração & dosagem , Álcool de Polivinil/química , Álcool de Polivinil/farmacocinética
3.
Proc Natl Acad Sci U S A ; 108(23): 9472-7, 2011 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21593423

RESUMO

Endothelial and endothelial progenitor cells (ECs and EPCs) play a fundamental role in angiogenesis that is essential for numerous physiological and pathological processes. The phosphatase and tensin homolog (PTEN)/ phosphoinositide 3-kinase (PI3K) pathway has been implicated in angiogenesis, but the mechanism in the regulation of this pathway in ECs and EPCs is poorly understood. Here we show that ARIA (apoptosis regulator through modulating IAP expression), a transmembrane protein that we recently identified, regulates the PTEN/PI3K pathway in ECs and EPCs and controls developmental and postnatal angiogenesis in vivo. We found that ARIA is abundantly expressed in EPCs and regulates their angiogenic functions by modulating PI3K/Akt/endothelial nitric oxide synthase (eNOS) signaling. Genetic deletion of ARIA caused nonfatal bleeding during embryogenesis, in association with increased small vessel density and altered expression of various vascular growth factors including angiopoietins and VEGF receptors. Postnatal neovascularization induced by critical limb ischemia was substantially enhanced in ARIA-null mice, in conjunction with more bone marrow (BM)-derived ECs detected in ischemic muscles. Administration of PI3K or NO synthase inhibitor completely abolished the enhanced neovascularization in ARIA(-/-) mice. Mechanistically, we identified that ARIA interacts with PTEN at the intracellular domain independently of the PTEN phosphorylation in its C-terminal tail. Overexpressed ARIA increased PTEN in the membrane fraction, whereas ARIA-silencing reduced the membrane-associated PTEN, resulting in modified PI3K/Akt signaling. Taken together, our findings establish a previously undescribed mode of regulation of the PTEN/PI3K/Akt pathway by ARIA, and reveal a unique mechanism in the control of angiogenesis. These functions of ARIA might offer a unique therapeutic potential.


Assuntos
Células Endoteliais/metabolismo , Neuregulina-1/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Vasos Sanguíneos/embriologia , Vasos Sanguíneos/crescimento & desenvolvimento , Vasos Sanguíneos/metabolismo , Células CHO , Linhagem Celular , Membrana Celular/metabolismo , Células Cultivadas , Cricetinae , Cricetulus , Células Endoteliais/citologia , Humanos , Immunoblotting , Imunoprecipitação , Camundongos , Camundongos Knockout , Mutação , Neuregulina-1/genética , Óxido Nítrico Sintase Tipo III/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Ligação Proteica , Interferência de RNA , Transdução de Sinais , Células-Tronco/citologia
4.
Molecules ; 19(9): 15298-313, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25255246

RESUMO

Self-assembled monolayers (SAMs) of tripod-shaped trithiols, consisting of an adamantane core with three CH2SH legs and a bithiophene group, were prepared on a Au(111) surface. Adsorption in a tripod-like fashion was supported by polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS) of the SAMs, which indicated the absence of free SH groups. Cyclic voltammetry showed an irreversible cathodic wave due to reductive desorption. The SAM also showed an anodic wave due to the single-electron oxidation of the bithiophene moiety without concomitant desorption of the molecules. Although oxidation was irreversible in the absence of a protecting group, it became reversible with the introduction of a terminal phenyl group. The charge of the oxidation was one-third that of the reductive desorption, confirming a three-point adsorption. The surface coverage was ca. 50% of that expected for the anti bithiophene conformation, which suggested that an increase in the surface area per molecule had been caused by the presence of an energetically high-lying syn conformer. In accordance with this, the line shape of the oxidation wave suggested an electrostatic repulsive interaction between neighboring molecules.


Assuntos
Ouro/química , Compostos de Sulfidrila/química , Tiofenos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
5.
Circulation ; 125(8): 1027-36, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22265909

RESUMO

BACKGROUND: We reported that phospholipase C (PLC)-δ1 activity was enhanced 3-fold in patients with coronary spastic angina. We detected variant PLC-δ1 with replacement of arginine 257 by histidine (R257H) showing increased enzymatic activity. We tested the hypothesis that increased PLC-δ1 activity causes enhanced coronary vasomotility. METHODS AND RESULTS: We generated transgenic (TG) mice with human R257H variant PLC-δ1 in vascular smooth muscle cells. PLC enzymatic activity in the coronary artery was increased by 2.57 and 1.89 times, respectively, in homozygous and heterozygous TG compared with wild-type (WT) mice. ST elevation after ergometrine occurred in 17 of 18 homozygous TG, 6 of 20 heterozygous TG, and 3 of 22 WT mice (P<0.01, homozygous TG versus WT; P<0.05, homozygous TG versus heterozygous TG; P=NS, heterozygous TG versus WT). ST elevation was associated with bradyarrhythmias in homozygous TG mice. Focal coronary artery narrowing was documented with the microvascular filling technique in 3 of 5 homozygous TG mice after ergometrine but not in any of 7 WT mice (P<0.05). In the isolated Langendorff hearts, coronary perfusion pressure was increased after ergometrine in homozygous TG mice (P<0.01) but not in heterozygous TG or WT mice. Coronary perfusion pressure increase after prostaglandin F2α was similar among homozygous TG, heterozygous TG, and WT mice. Cultured rat aortic smooth muscle cells transfected with variant PLC-δ1 showed a higher PLC activity than those with WT PLC-δ1 (P<0.05) and furthermore showed greater intracellular Ca2+ response to acetylcholine in variant than in WT PLC-δ1 (P<0.05). CONCLUSIONS: Increased PLC-δ1 activity enhances coronary vasomotility such as that seen in patients with coronary spastic angina.


Assuntos
Vasoespasmo Coronário/enzimologia , Vasoespasmo Coronário/genética , Fosfolipase C delta/genética , Animais , Células Cultivadas , Circulação Coronária/genética , Vasoespasmo Coronário/patologia , Indução Enzimática/genética , Variação Genética/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfolipase C delta/biossíntese , Ratos , Regulação para Cima/genética
6.
Am J Physiol Heart Circ Physiol ; 305(5): H667-75, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23812390

RESUMO

Chronic kidney disease (CKD) is an independent risk factor for the development of cardiovascular disease. The perivascular adipose tissue is closely implicated in the development of atherosclerosis; however, the contribution to CKD-associated atherogenesis remains undefined. Eight-week-old apoE-deficient mice were uninephrectomized and fed a high-cholesterol diet starting at 12 wk of age. The atherosclerotic lesion area in the thoracic aorta was comparable in 16-wk-old uninephrectomized (UNX) mice and sham control mice; however, the lesion area was markedly exaggerated in 20-wk-old UNX mice compared with the control (54%, P < 0.05). While the accumulation of monocytes/macrophages and the mRNA expression levels of inflammatory cytokines/chemokines in the thoracic periaortic adipose tissue (PAT) did not differ between the two groups, angiotensinogen (AGT) mRNA expression and the angiotensin II (ANG II) concentration in the PAT were significantly higher in 16-wk-old UNX mice than in the control (1.9- and 1.5-fold increases vs. control, respectively; P < 0.05). ANG II concentrations in both the plasma and epididymal white adipose tissue (WAT) were comparable between the two groups, suggesting that PAT-specific activation of the renin-angiotensin system (RAS) is primarily involved in CKD-associated atherogenesis. The homeostasis model assessment-insulin resistance (HOMA-IR) index and plasma insulin level after glucose loading were significantly elevated in 16-wk-old UNX mice. In vitro stimulation of preadipocytes with insulin exaggerated the AGT mRNA expression along with increased mRNA expression of PPARγ. These findings suggest that PAT-specific RAS activation probably primarily contributes in accelerating atherosclerotic development in UNX mice and could thus represent a therapeutic target for preventing CKD-associated atherogenesis.


Assuntos
Tecido Adiposo/fisiopatologia , Aorta Torácica/fisiopatologia , Apolipoproteínas E/deficiência , Aterosclerose/fisiopatologia , Nefrectomia/efeitos adversos , Insuficiência Renal Crônica/fisiopatologia , Sistema Renina-Angiotensina/fisiologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Angiotensina II/metabolismo , Angiotensinogênio/metabolismo , Animais , Aorta Torácica/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/etiologia , Aterosclerose/metabolismo , Colesterol na Dieta/efeitos adversos , Modelos Animais de Doenças , Insulina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR gama/metabolismo , Insuficiência Renal Crônica/etiologia
7.
Biochem Biophys Res Commun ; 432(1): 105-10, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23376071

RESUMO

Much recent work has highlighted the key role of adipose tissue as an endocrine organ that secretes a number of adipocytokines, linking adiposity, especially intra-abdominal visceral fat, and the pathogenesis of cardiovascular and metabolic diseases. However, the role of epicardial adipose tissue (EAT), another important visceral fat depot situated in close proximity to epicardial coronary arteries and myocardium, has been less well studied. In this study, we sought to characterize EAT by comparing gene expression profiles of EAT, omental adipose tissue (OAT), and subcutaneous adipose tissue (SCAT) in patients who underwent elective coronary artery bypass graft surgery for critical coronary artery disease (CAD) and identify molecules involved in inflammation. A total of 15,304 probes were detected in all depots, and 231 probes were differentially expressed. Significantly higher expression of pro-inflammatory genes such as interleukin-1ß, -6, and -8, and chemokine receptor 2 was observed in EAT, even when compared with OAT. Among them, serglycin was one of the most abundantly expressed genes in EAT. Serglycin expression was induced during adipocytic differentiation of 3T3L1 cells. Serglycin was secreted from adipocytes, and tumor necrosis factor-α stimulated its expression and secretion in adipocytes. Serglycin was also present in human serum samples. These results suggest that human EAT has strong inflammatory properties in patients with CAD and provide novel evidence that serglycin is an adipocytokine highly expressed in EAT.


Assuntos
Adipocinas/biossíntese , Tecido Adiposo/metabolismo , Doença da Artéria Coronariana/metabolismo , Pericárdio/metabolismo , Proteoglicanas/biossíntese , Proteínas de Transporte Vesicular/biossíntese , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Adipocinas/genética , Animais , Doença da Artéria Coronariana/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Camundongos , Proteoglicanas/genética , Transcriptoma , Fator de Necrose Tumoral alfa/farmacologia , Proteínas de Transporte Vesicular/genética
8.
Langmuir ; 29(13): 4275-82, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23470152

RESUMO

A dyad consisting of a tripod-shaped trithiol with an adamantane core and a terminal ferrocenyl group linked through ap-phenyleneethynylene bridge was synthesized. The trithiol formed a stable self-assembled monolayer (SAM) on Au(111), wherein each molecule is bound to the surface by three-point adsorption using all sulfur atoms, with confirmation by PM-IRRAS and XPS analyses. Cyclic voltammetry of the SAM showed a line shape typical of an ideal adsorbed system, that is, a monolayer with negligible electrostatic interaction among the terminal ferrocenyl groups. Thus, a rare SAM was achieved, in which the component molecules were isolated from adjacent molecules without the coadsorption of nonelectroactive molecules.


Assuntos
Compostos Ferrosos/química , Ouro/química , Compostos de Sulfidrila/química , Adamantano/química , Alcinos/química , Éteres/química , Metalocenos , Modelos Moleculares , Estrutura Molecular , Oxirredução , Compostos de Sulfidrila/síntese química , Propriedades de Superfície
9.
Heart Vessels ; 28(1): 27-33, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22124530

RESUMO

It is well known that silent myocardial ischemia (SMI) often complicates patients with cerebral infarction and that stroke patients often die of ischemic heart disease. Therefore, it is considered important to treat myocardial ischemia in stroke patients. This study investigated SMI complicating Japanese patients with fresh stroke, using (99m)Tc-tetrofosmin myocardial scintigraphy with pharmacologic stress testing to elucidate their clinical manifestations. This study included 41 patients (26 men, mean age 76.0 ± 10.7 years) with acute cerebral infarction and no history of coronary artery disease. All patients underwent (99m)Tc-tetrofosmin myocardial scintigraphy with intravenous administration of adenosine to diagnose SMI. Of the 41 patients, myocardial ischemia was confirmed in 17 patients (41.5%). Atherosclerotic etiology was the major cause of stroke in the ischemia(+) group and embolic origin was the major cause in the ischemia(-) group. Patients with myocardial ischemia had a higher incidence of diabetes mellitus (52.9 vs 20.8%; P = 0.0323) and more than two conventional cardiovascular risk factors (64.7 vs 25.0%; P = 0.0110) compared with the nonischemic patients. Infarction subtype of atherosclerotic origin was an independent positive predictor of asymptomatic myocardial ischemia in patients with stroke. These findings indicate that the prevalence of asymptomatic myocardial ischemia is relatively high, especially in patients with stroke of atherosclerotic origin. Therefore, it is beneficial for us to narrow the target population who are at the highest risk when screening for SMI in Japanese patients with acute cerebral infarction.


Assuntos
Adenosina , Infarto Cerebral/complicações , Imagem de Perfusão do Miocárdio/métodos , Compostos Organofosforados , Compostos de Organotecnécio , Doença Aguda , Idoso , Infarto Cerebral/diagnóstico , Angiografia Coronária , Diagnóstico Diferencial , Teste de Esforço , Feminino , Seguimentos , Humanos , Incidência , Japão/epidemiologia , Masculino , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Prognóstico , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada de Emissão de Fóton Único , Vasodilatadores
10.
Heart Vessels ; 28(4): 434-41, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22926409

RESUMO

Data regarding relationship between pulse pressure (PP) at admission and in-hospital outcome in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) are still lacking. A total of 1413 primary PCI-treated AMI patients were classified into quintiles based on admission PP (<40, n = 280; 40-48, n = 276; 49-57, n = 288; 58-70, n = 288; and ≥71 mmHg, n = 281). The patients with PP < 40 mmHg tended to have higher prevalence of male, smoking, and Killip class ≥3 at admission; right coronary artery, left main trunk (LMT), or multivessels as culprit lesions; larger number of diseased vessels; lower Thrombolysis in Myocardial Infarction (TIMI) grade in the infarct-related artery before/after primary PCI; and higher value of peak creatine phosphokinase concentration. Patients with PP < 40 mmHg had highest mortality, while patients with PP 49-57 mmHg had the lowest: 11.8 % (<40), 7.2 % (40-48), 2.8 % (49-57), 5.9 % (58-70), and 6.0 % (≥71 mmHg). On multivariate analysis, Killip class ≥3 at admission, LMT or multivessels as culprit lesions, chronic kidney disease, and age were the independent positive predictors of the in-hospital mortality, whereas admission PP 49-57 mmHg, hypercholesterolemia, and TIMI 3 flow before/after PCI were the negative ones, but admission PP < 40 mmHg was not. These results suggest that admission PP 49-57 mmHg might be correlated with better in-hospital prognosis in Japanese AMI patients undergoing primary PCI.


Assuntos
Pressão Sanguínea , Infarto do Miocárdio/terapia , Admissão do Paciente , Intervenção Coronária Percutânea , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Humanos , Japão , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Razão de Chances , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 107(45): 19308-13, 2010 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-20966350

RESUMO

Klotho is a circulating protein, and Klotho deficiency disturbs endothelial integrity, but the molecular mechanism is not fully clarified. We report that vascular endothelium in Klotho-deficient mice showed hyperpermeability with increased apoptosis and down-regulation of vascular endothelial (VE)-cadherin because of an increase in VEGF-mediated internal calcium concentration ([Ca(2+)]i) influx and hyperactivation of Ca(2+)-dependent proteases. Immunohistochemical analysis, the pull-down assay using Klotho-fixed agarose, and FRET confocal imaging confirmed that Klotho protein binds directly to VEGF receptor 2 (VEGFR-2) and endothelial, transient-receptor potential canonical Ca(2+) channel 1 (TRPC-1) and strengthens the association to promote their cointernalization. An in vitro mutagenesis study revealed that the second hydrolase domain of Klotho interacts with sixth and seventh Ig domains of VEGFR-2 and the third extracellular loop of TRPC-1. In Klotho-deficient endothelial cells, VEGF-mediated internalization of the VEGFR-2/TRPC-1 complex was impaired, and surface TRPC-1 expression increased 2.2-fold; these effects were reversed by supplementation of Klotho protein. VEGF-mediated elevation of [Ca(2+)]i was sustained at higher levels in an extracellular Ca(2+)-dependent manner, and normalization of TRCP-1 expression restored the abnormal [Ca(2+)]i handling. These findings provide evidence that Klotho protein is associated with VEGFR-2/TRPC-1 in causing cointernalization, thus regulating TRPC-1-mediated Ca(2+) entry to maintain endothelial integrity.


Assuntos
Glucuronidase/metabolismo , Canais de Cátion TRPC/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Sítios de Ligação , Cálcio/metabolismo , Canais de Cálcio , Glucuronidase/deficiência , Proteínas Klotho , Camundongos , Ligação Proteica
12.
Radiol Phys Technol ; 16(2): 186-194, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36780121

RESUMO

Although a 6-MV X-ray beam is employed clinically as a non-neutron-producing beam, no studies have reported how few neutrons are produced from a 6-MV beam. This study aimed to theoretically deduce the neutron dose from a 6-MV beam using Monte Carlo simulations for the notification of safety and risk in radiotherapy. Nuclei from a nuclear database with neutron separation energies below 6 MeV were surveyed, suggesting that the certain content of 2H in the human body may result in some contribution. Thus, Monte Carlo calculation considering 2H in a phantom was performed. The calculation suggested that the distribution of the neutron dose from a 6-MV beam consisted of two components: one had neutrons from 2H concentrated within an irradiation field, and the other had those due to other elements such as 183W spreading from a gantry head to a treatment room. Although uncertainty owing to the normalization factor of the Monte Carlo calculations was a factor of three, the neutron doses at distances of 0 and 50 cm from an irradiation field were calculated as 27 and 1.5 nSv/MU, respectively, under intensity-modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT). The calculations suggest that neutrons produced by a 6-MV beam are approximately 70 and 20 times safer than those by a 10-MV beam in the case of IMRT/VMAT and total body irradiation, respectively. Thus, this study theoretically reported the approximate number of neutrons delivered by a 6-MV beam for the first time.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Raios X , Radiografia , Nêutrons , Bases de Dados Factuais , Método de Monte Carlo , Dosagem Radioterapêutica
13.
J Mol Cell Cardiol ; 52(1): 175-84, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22044588

RESUMO

Inhibition of tumor suppressor p53 is cardioprotective against ischemic injury and provides resistance to subsequent cardiac remodeling. We investigated p53-mediated expansion of ischemic damage with a focus on mitochondrial integrity in association with autophagy and apoptosis. p53(-/-) heart showed that autophagic flux was promoted under ischemia without a change in cardiac tissue ATP content. Electron micrographs revealed that ischemic border zone in p53(-/-) mice had 5-fold greater numbers of autophagic vacuoles containing mitochondria, indicating the occurrence of mitophagy, with an apparent reduction of abnormal mitochondria compared with those in WT mice. Analysis of autophagic mediators acting downstream of p53 revealed that TIGAR (TP53-induced glycolysis and apoptosis regulator) was exclusively up-regulated in ischemic myocardium. TIGAR(-/-) mice exhibited the promotion of mitophagy followed by decrease of abnormal mitochondria and resistance to ischemic injury, consistent with the phenotype of p53(-/-) mice. In p53(-/-) and TIGAR(-/-) ischemic myocardium, ROS production was elevated and followed by Bnip3 activation which is an initiator of mitophagy. Furthermore, the activation of Bnip3 and mitophagy due to p53/TIGAR inhibition were reversed with antioxidant N-acetyl-cysteine, indicating that this adaptive response requires ROS signal. Inhibition of mitophagy using chloroquine in p53(-/-) or TIGAR(-/-) mice exacerbated accumulation of damaged mitochondria to the level of wild-type mice and attenuated cardioprotective action. These findings indicate that p53/TIGAR-mediated inhibition of myocyte mitophagy is responsible for impairment of mitochondrial integrity and subsequent apoptosis, the process of which is closely involved in p53-mediated ventricular remodeling after myocardial infarction.


Assuntos
Isquemia Miocárdica/metabolismo , Proteínas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/genética , Proteínas Reguladoras de Apoptose , Autofagia/genética , Regulação da Expressão Gênica , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Isquemia Miocárdica/genética , Estresse Oxidativo , Monoéster Fosfórico Hidrolases , Proteínas/genética , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Remodelação Ventricular/genética
14.
Kidney Int ; 81(5): 449-57, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22157654

RESUMO

Unilateral ureteral obstruction is a well-established experimental model of progressive renal fibrosis. We tested whether mechanical stretch and subsequent renal tubular distension might lead to renal fibrosis by first studying renal tubular epithelial cells in culture. We found that mechanical stretch induced reactive oxygen species that in turn activated the cytoplasmic proline-rich tyrosine kinase-2 (Pyk2). This kinase is abundantly expressed in tubular epithelial cells where it is activated by several stimuli. Using mice with deletion of Pyk2 we found that the expression of transforming growth factor-ß1 induced by mechanical stretch in renal tubular epithelial cells was significantly reduced. The expression of connective tissue growth factor was also reduced in the Pyk2(-/-) mice. We also found that expression of connective tissue growth factor was independent of transforming growth factor-ß1, but dependent on the Rho-associated coiled-coil forming protein kinase pathway. Thus, Pyk2 may be an important initiating factor in renal fibrosis and might be a new therapeutic target for ameliorating renal fibrosis.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Quinase 2 de Adesão Focal/metabolismo , Túbulos Renais/metabolismo , Rim/metabolismo , Rim/patologia , Estresse Mecânico , Animais , Células Cultivadas , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibrose , Quinase 2 de Adesão Focal/deficiência , Quinase 2 de Adesão Focal/genética , Túbulos Renais/patologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/complicações
15.
Biochem Biophys Res Commun ; 426(3): 317-23, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22935419

RESUMO

While nuclear factor of activated T cells 5 (NFAT5), a transcription factor implicated in osmotic stress response, is suggested to be involved in other processes such as migration and proliferation, its role in cardiomyogenesis is largely unknown. Here, we examined the role of NFAT5 in cardiac differentiation of P19CL6 cells, and observed that it was abundantly expressed in undifferentiated P19CL6 cells, and its protein expression was significantly downregulated by enhanced proteasomal degradation during DMSO-induced cardiomyogenesis. Expression of a dominant negative mutant of NFAT5 markedly attenuated cardiomyogenesis, which was associated with the inhibition of mesodermal differentiation. TOPflash reporter assay revealed that the transcriptional activity of canonical Wnt signaling was activated prior to mesodermal differentiation, and this activation was markedly attenuated by NFAT5 inhibition. Pharmacological activation of canonical Wnt signaling by [2'Z, 3'E]-6-bromoindirubin-3'-oxime (BIO) restored Brachyury expression in NFAT5DN-expressing cells. Inhibition of NFAT5 markedly attenuated Wnt3 and Wnt3a induction. Expression of Dkk1 and Cerberus1, which are secreted Wnt antagonists, was also inhibited by NFAT5 inhibition. Thus, endogenous NFAT5 regulates the coordinated expression of Wnt ligands and antagonists, which are essential for cardiomyogenesis through the canonical Wnt pathway. These results demonstrated a novel role of NFAT5 in cardiac differentiation of stem cells.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Coração/embriologia , Miócitos Cardíacos/citologia , Organogênese , Fatores de Transcrição/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Linhagem Celular Tumoral , Citocinas , Regulação para Baixo , Células-Tronco Embrionárias/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/metabolismo , Proteólise , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
16.
Biochem Biophys Res Commun ; 428(4): 500-5, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23123625

RESUMO

PARM-1, prostatic androgen repressed message-1, is an endoplasmic reticulum (ER) molecule that is involved in ER stress-induced apoptosis in cardiomyocytes. In this study, we assessed whether PARM-1 plays a role in the differentiation of stem cells into cardiomyocytes. While PARM-1 was not expressed in undifferentiated P19CL6 embryonic carcinoma cells, PARM-1 expression was induced during cardiomyogenic differentiation. This expression followed expression of mesodermal markers, and preceded expression of cardiac transcription factors. PARM-1 overexpression did not alter the expression of undifferentiated markers and the proliferative property in undifferentiated P19CL6 cells. Expression of cardiac transcription factors during cardiomyogenesis was markedly enhanced by overexpression of PARM-1, while expression of mesodermal markers was not altered, suggesting that PARM-1 is involved in the differentiation from the mesodermal lineage to cardiomyocytes. Furthermore, overexpression of PARM-1 induced BMP2 mRNA expression in undifferentiated P19CL6 cells and enhanced both BMP2 and BMP4 mRNA expression in the early phase of cardiomyogenesis. PARM-1 overexpression also enhanced phosphorylation of Smads1/5/8. Thus, PARM-1 plays an important role in the cardiomyogenic differentiation of P19CL6 cells through regulating BMP/Smad signaling pathways, demonstrating a novel role of PARM-1 in the cardiomyogenic differentiation of stem cells.


Assuntos
Proteína de Ligação a Androgênios/fisiologia , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Coração/embriologia , Desenvolvimento Muscular , Mioblastos Cardíacos/citologia , Miócitos Cardíacos/citologia , Proteínas Smad/metabolismo , Proteína de Ligação a Androgênios/genética , Animais , Linhagem Celular Tumoral , Camundongos , Mioblastos Cardíacos/metabolismo , Transdução de Sinais
17.
Biochem Biophys Res Commun ; 425(1): 39-44, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22820183

RESUMO

Vascular calcification is a major risk factor for the cardiovascular disease, yet its underlying molecular mechanisms remain to be elucidated. Recently, we identified that osteogenic signals via bone morphogenetic protein (BMP)-2 exerted by vascular smooth muscle cells (VSMCs) play a crucial role in the formation of atherosclerotic plaque calcification. Here we report a synergistic interaction between macrophages and VSMCs with respect to plaque calcification. Treatment with conditioned medium (CM) of macrophages dramatically enhanced BMP-2 expression in VSMCs, while it substantially reduced the expression of matrix Gla-protein (MGP) that inhibits the BMP-2 osteogenic signaling. As a result, macrophages significantly accelerated the osteoblastic differentiation of C2C12 cells induced by VSMC-CM. In contrast, macrophage-CM did not enhance the osteoblastic gene expressions in VSMCs, indicating that macrophages unlikely induced the osteoblastic trans-differentiation of VSMCs. We then examined the effect of recombinant TNF-α and IL-1ß on the VSMC-derived osteogenic signals. Similar to the macrophage-CM, both cytokines enhanced BMP-2 expression and reduced MGP expression in VSMCs. Nevertheless, only the neutralization of TNF-α but not IL-1ß attenuated the effect of macrophage-CM on the expression of these genes in VSMCs, due to the very low concentration of IL-1ß in the macrophage-CM. On the other hand, VSMCs significantly enhanced IL-1ß expression in macrophages, which might in turn accelerate the VSMC-mediated osteogenic signals. Together, we identified a unique role of macrophages in the formation of plaque calcification in coordination with VSMCs. This interaction between macrophages and VSMCs is a potential therapeutic target to treat and prevent the atherosclerotic plaque calcification.


Assuntos
Macrófagos/imunologia , Músculo Liso Vascular/imunologia , Miócitos de Músculo Liso/imunologia , Osteogênese/imunologia , Placa Aterosclerótica/imunologia , Calcificação Vascular/imunologia , Proteína Morfogenética Óssea 2/biossíntese , Proteínas de Ligação ao Cálcio/biossíntese , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Proteínas da Matriz Extracelular/biossíntese , Humanos , Interleucina-1beta/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Osteoblastos/imunologia , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Calcificação Vascular/tratamento farmacológico , Proteína de Matriz Gla
18.
Arterioscler Thromb Vasc Biol ; 31(5): 1084-92, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21372295

RESUMO

OBJECTIVE: Reactive oxygen species (ROS) are involved in the initial process of atherosclerosis, whereas it remains to be determined how atherogenic stimulus causes ROS-mediated proinflammatory reactions. Here, we focused on proline-rich tyrosine kinase (PYK2)-mediated ROS generation and examined how atherogenic stimulus causes early proinflammatory reactions. METHODS AND RESULTS: PYK2-deficient (knockout [KO]) (PYK2-KO) mice were crossbred with apolipoprotein E (ApoE)-deficient (PYK2-KO/ApoE-KO) mice. PYK2-KO/ApoE-KO mice and endothelial cells (EC) were used for the study. Aortic atherogenic lesions in PYK2-KO/ApoE-KO mice were markedly decreased (55% versus ApoE-KO) after 8 weeks of a Western diet. Aortic PYK2 was activated as early as 7 days after the Western diet, when inflammatory cells were not yet activated. Addition of the proatherogenic oxidized phospholipid lysophosphatidylcholine caused activation of endothelial PYK2. Lysophosphatidylcholine-activated PYK2 induced NADPH oxidase-mediated ROS generation and ROS-mediated synthesis of tumor necrosis factor-α (TNFα), vascular cell adhesion molecule-1 (VCAM-1), monocyte chemotactic protein-1 (MCP-1), and p21Cip1/Ets-1. Neutralizing anti-TNFα antibody or knockdown of p21Cip1/Ets-1 system blocked the induction of VCAM-1 and MCP-1. PYK2 deficiency abolished these ROS-mediated proinflammatory reactions. Further analysis revealed that PYK2/ROS-mediated p21Cip1/Ets-1 activation upregulated the transcription of the MCP-1 gene in collaboration with p300 transcription coactivator. CONCLUSIONS: PYK2 is a key tyrosine kinase activated by high cholesterol exposure, which causes ROS-mediated TNFα release and induces TNFα-dependent expression of proinflammatory molecules via the p21Cip1/Ets-1/p300 transcription system.


Assuntos
Doenças da Aorta/enzimologia , Aterosclerose/enzimologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células Endoteliais/enzimologia , Quinase 2 de Adesão Focal/metabolismo , Mediadores da Inflamação/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Doenças da Aorta/genética , Doenças da Aorta/patologia , Doenças da Aorta/prevenção & controle , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Transplante de Medula Óssea , Células Cultivadas , Quimiocina CCL2/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Células Endoteliais/patologia , Quinase 2 de Adesão Focal/deficiência , Quinase 2 de Adesão Focal/genética , Hipercolesterolemia/enzimologia , Hipercolesterolemia/genética , Lipoproteínas LDL/metabolismo , Lisofosfatidilcolinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidases/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Ativação Transcricional , Transfecção , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fatores de Transcrição de p300-CBP/genética
19.
Circ J ; 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22987054

RESUMO

BACKGROUND: The KYOTO HEART Study demonstrated that Valsartan Add-on treatment was effective to reduce new-onset diabetes in high-risk hypertensive patients. The purpose of the present study was to examine the effects of Valsartan Add-on treatment on cardiovascular (CV) events in patients with or without diabetes. METHODS AND RESULTS: A total of 3,031 patients were divided at baseline: Baseline Diabetes (n=807) and Baseline Non-Diabetes (n=2,224). Among the Non-Diabetes patients, 144 developed diabetes (New-Onset Diabetes) and the remaining patients did not throughout the study (Final Non-Diabetes, n=2,080). Baseline Diabetes showed significantly higher CV event rates than Baseline Non-Diabetes (10.3% vs. 7.0%, P=0.00400). Valsartan Add-on treatment significantly reduced CV event rates than Non-angiotensin receptor blocker (ARB) treatment both in Baseline Diabetes (6.7% vs. 13.8%, P=0.00274) and in Baseline Non-Diabetes (5.0% vs. 8.9%, P=0.00036), respectively. New-Onset Diabetes showed a similar CV event rate (12.5%) to Baseline Diabetes (10.3%) but the event rate was significantly higher than that of Final Non-Diabetes (6.6%, P=0.0065). In the New-Onset Diabetes, Valsartan add-on treatment significantly reduced CV event rate than Non-ARB treatment (5.2% vs. 17.4%, P=0.04601). CONCLUSIONS: CV event risk in New-Onset Diabetes was relatively equivalent to Baseline Diabetes. Valsartan Add-on treatment was effective for the reduction of CV events not only in Baseline Diabetes but also in New-Onset Diabetes.

20.
Heart Vessels ; 27(6): 634-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22218740

RESUMO

Although cisplatin is indispensable for the chemotherapy treatment of many malignancies, cisplatin-associated thrombosis is attracting increasing attention. However, experience of primary percutaneous coronary intervention (PCI) and intravascular ultrasound imaging (IVUS) for coronary thrombosis, possibly due to cisplatin-based chemotherapy, has been limited. Case 1 with postoperative gastric cancer developed acute myocardial infarction (AMI) on the sixth day of the second chemotherapy course with conventional doses of cisplatin and tegafur gimeracil oteracil potassium. Emergency coronary angiography (CAG) showed a filling defect in the proximal left anterior descending coronary artery (LAD) concomitant with no reflow in the distal LAD. Case 2 with advanced lung cancer and brain metastasis suffered AMI on the fifth day of the first chemotherapy course with conventional doses of cisplatin and gemcitabine. Emergency CAG delineated a total occlusion in the proximal right coronary artery. In both cases, thrombectomy using aspiration catheter alone obtained optimal angiographic results and subsequent IVUS revealed no definite atherosclerotic plaque, while slow flow still remained even after selective intra-coronary infusion of vasodilator in the case 1. These cases suggest that primary PCI using thrombus-aspiration catheter might be safe and effective for coronary thrombosis due to cisplatin-based chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Trombose Coronária/diagnóstico por imagem , Trombose Coronária/terapia , Intervenção Coronária Percutânea , Ultrassonografia de Intervenção , Adulto , Cisplatino/efeitos adversos , Angiografia Coronária , Trombose Coronária/induzido quimicamente , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Neoplasias Gástricas/tratamento farmacológico , Trombectomia , Resultado do Tratamento
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