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2.
Circulation ; 140(21): 1737-1752, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31564129

RESUMEN

BACKGROUND: Heart failure is a complex syndrome that results from structural or functional impairment of ventricular filling or blood ejection. Protein phosphorylation is a major and essential intracellular mechanism that mediates various cellular processes in cardiomyocytes in response to extracellular and intracellular signals. The RHOA-associated protein kinase (ROCK/Rho-kinase), an effector regulated by the small GTPase RHOA, causes pathological phosphorylation of proteins, resulting in cardiovascular diseases. RHOA also activates protein kinase N (PKN); however, the role of PKN in cardiovascular diseases remains unclear. METHODS: To explore the role of PKNs in heart failure, we generated tamoxifen-inducible, cardiomyocyte-specific PKN1- and PKN2-knockout mice by intercrossing the αMHC-CreERT2 line with Pkn1flox/flox and Pkn2flox/flox mice and applied a mouse model of transverse aortic constriction- and angiotensin II-induced heart failure. To identify a novel substrate of PKNs, we incubated GST-tagged myocardin-related transcription factor A (MRTFA) with recombinant GST-PKN-catalytic domain or GST-ROCK-catalytic domain in the presence of radiolabeled ATP and detected radioactive GST-MRTFA as phosphorylated MRTFA. RESULTS: We demonstrated that RHOA activates 2 members of the PKN family of proteins, PKN1 and PKN2, in cardiomyocytes of mice with cardiac dysfunction. Cardiomyocyte-specific deletion of the genes encoding Pkn1 and Pkn2 (cmc-PKN1/2 DKO) did not affect basal heart function but protected mice from pressure overload- and angiotensin II-induced cardiac dysfunction. Furthermore, we identified MRTFA as a novel substrate of PKN1 and PKN2 and found that MRTFA phosphorylation by PKN was considerably more effective than that by ROCK in vitro. We confirmed that endogenous MRTFA phosphorylation in the heart was induced by pressure overload- and angiotensin II-induced cardiac dysfunction in wild-type mice, whereas cmc-PKN1/2 DKO mice suppressed transverse aortic constriction- and angiotensin II-induced phosphorylation of MRTFA. Although RHOA-mediated actin polymerization accelerated MRTFA-induced gene transcription, PKN1 and PKN2 inhibited the interaction of MRTFA with globular actin by phosphorylating MRTFA, causing increased serum response factor-mediated expression of cardiac hypertrophy- and fibrosis-associated genes. CONCLUSIONS: Our results indicate that PKN1 and PKN2 activation causes cardiac dysfunction and is involved in the transition to heart failure, thus providing unique targets for therapeutic intervention for heart failure.


Asunto(s)
Actinas/metabolismo , Insuficiencia Cardíaca/enzimología , Miocitos Cardíacos/enzimología , Proteína Quinasa C/metabolismo , Transactivadores/metabolismo , Animales , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Miocitos Cardíacos/patología , Fosforilación , Unión Proteica , Proteína Quinasa C/deficiencia , Proteína Quinasa C/genética , Transducción de Señal , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo
3.
Circ Res ; 123(12): 1326-1338, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30566056

RESUMEN

RATIONALE: Physical exercise provides benefits for various organ systems, and some of systemic effects of exercise are mediated through modulation of muscle-derived secreted factors, also known as myokines. Myonectin/C1q (complement component 1q)/TNF (tumor necrosis factor)-related protein 15/erythroferrone is a myokine that is upregulated in skeletal muscle and blood by exercise. OBJECTIVE: We investigated the role of myonectin in myocardial ischemic injury. METHODS AND RESULTS: Ischemia-reperfusion in myonectin-knockout mice led to enhancement of myocardial infarct size, cardiac dysfunction, apoptosis, and proinflammatory gene expression compared with wild-type mice. Conversely, transgenic overexpression of myonectin in skeletal muscle reduced myocardial damage after ischemia-reperfusion. Treadmill exercise increased circulating myonectin levels in wild-type mice, and it reduced infarct size after ischemia-reperfusion in wild-type mice, but not in myonectin-knockout mice. Treatment of cultured cardiomyocytes with myonectin protein attenuated hypoxia/reoxygenation-induced apoptosis via S1P (sphingosine-1-phosphate)-dependent activation of cAMP/Akt cascades. Similarly, myonectin suppressed inflammatory response to lipopolysaccharide in cultured macrophages through the S1P/cAMP/Akt-dependent signaling pathway. Moreover, blockade of S1P-dependent pathway reversed myonectin-mediated reduction of myocardial infarct size in mice after ischemia-reperfusion. CONCLUSIONS: These data indicate that myonectin functions as an endurance exercise-induced myokine which ameliorates acute myocardial ischemic injury by suppressing apoptosis and inflammation in the heart, suggesting that myonectin mediates some of the beneficial actions of exercise on cardiovascular health.


Asunto(s)
Citocinas/metabolismo , Proteínas Musculares/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Condicionamiento Físico Animal/métodos , Animales , Apoptosis , Células Cultivadas , AMP Cíclico/metabolismo , Citocinas/genética , Citocinas/farmacología , Lisofosfolípidos/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Musculares/genética , Proteínas Musculares/farmacología , Músculo Esquelético/metabolismo , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células RAW 264.7 , Esfingosina/análogos & derivados , Esfingosina/metabolismo
4.
J Mol Cell Cardiol ; 133: 174-187, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31220468

RESUMEN

The mammalian heart undergoes complex structural and functional remodeling to compensate for stresses such as pressure overload. While studies suggest that, at best, the adult mammalian heart is capable of very limited regeneration arising from the proliferation of existing cardiomyocytes, how myocardial stress affects endogenous cardiac regeneration or repair is unknown. To define the relationship between left ventricular afterload and cardiac repair, we induced left ventricle pressure overload in adult mice by constriction of the ascending aorta (AAC). One week following AAC, we normalized ventricular afterload in a subset of animals through removal of the aortic constriction (de-AAC). Subsequent monitoring of cardiomyocyte cell cycle activity via thymidine analog labeling revealed that an acute increase in ventricular afterload induced cardiomyocyte proliferation. Intriguingly, a release in ventricular overload (de-AAC) further increases cardiomyocyte proliferation. Following both AAC and de-AAC, thymidine analog-positive cardiomyocytes exhibited characteristics of newly generated cardiomyocytes, including single diploid nuclei and reduced cell size as compared to age-matched, sham-operated adult mouse myocytes. Notably, those smaller cardiomyocytes frequently resided alongside one another, consistent with local stimulation of cellular proliferation. Collectively, our data demonstrate that adult cardiomyocyte proliferation can be locally stimulated by an acute increase or decrease of ventricular pressure, and this mode of stimulation can be harnessed to promote cardiac repair.


Asunto(s)
Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Presión Ventricular , Remodelación Ventricular , Animales , Biomarcadores , Cardiomegalia/etiología , Cardiomegalia/metabolismo , Cardiomegalia/patología , Cardiomegalia/fisiopatología , Proliferación Celular , Modelos Animales de Enfermedad , Ecocardiografía , Técnica del Anticuerpo Fluorescente , Expresión Génica , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/metabolismo , Hipertrofia Ventricular Izquierda/patología , Ratones , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Estrés Oxidativo
5.
J Nucl Cardiol ; 26(1): 288-297, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-28432673

RESUMEN

BACKGROUND: This study aimed to investigate whether indices of left ventricular (LV) dyssynchrony by gated myocardial perfusion SPECT (GMPS) could be useful to predict prognosis in chronic kidney disease (CKD) patients with normal perfusion defect scores. METHODS: One hundred and sixty-seven CKD patients with normal perfusion defect scores on adenosine-stress 201Tl GMPS and no previous history of overt heart diseases were enrolled. Phase standard deviation (PSD) and bandwidth (BW) were automatically calculated from GMPS. The major adverse cardiac events (MACEs) for a mean of 560 days were defined as sudden cardiac death, fatal arrhythmias, and acute coronary syndrome requiring urgent coronary revascularization. Patients were divided into two groups according to the presence or absence of MACEs. RESULTS: The MACEs occurred in 12 patients (7.1%). Patients who experienced MACEs showed significantly higher PSD and wider BW than those who did not. In the Kaplan-Meier event-free survival analysis, cardiac event rate was significantly higher in the high-PSD and wide-BW group (n = 81) than in the low-PSD and narrow-BW group (n = 71) (P = .002). The multivariate regression analysis revealed that the PSD was associated with MACEs (odds ratio 1.33, 95% confidence interval 1.05-1.69, P = .01). CONCLUSION: The LV dyssynchrony indices from GMPS may be novel prognostic predictors in CKD patients with normal perfusion defect scores.


Asunto(s)
Fallo Renal Crónico/diagnóstico por imagen , Imagen de Perfusión Miocárdica , Tomografía Computarizada de Emisión de Fotón Único , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano , Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Radioisótopos de Talio , Resultado del Tratamiento
6.
Circ Res ; 117(5): 450-9, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26082557

RESUMEN

RATIONALE: In response to injury, the rodent heart is capable of virtually full regeneration via cardiomyocyte proliferation early in life. This regenerative capacity, however, is diminished as early as 1 week postnatal and remains lost in adulthood. The mechanisms that dictate postinjury cardiomyocyte proliferation early in life remain unclear. OBJECTIVE: To delineate the role of miR-34a, a regulator of age-associated physiology, in regulating cardiac regeneration secondary to myocardial infarction (MI) in neonatal and adult mouse hearts. METHODS AND RESULTS: Cardiac injury was induced in neonatal and adult hearts through experimental MI via coronary ligation. Adult hearts demonstrated overt cardiac structural and functional remodeling, whereas neonatal hearts maintained full regenerative capacity and cardiomyocyte proliferation and recovered to normal levels within 1-week time. As early as 1 week postnatal, miR-34a expression was found to have increased and was maintained at high levels throughout the lifespan. Intriguingly, 7 days after MI, miR-34a levels further increased in the adult but not neonatal hearts. Delivery of a miR-34a mimic to neonatal hearts prohibited both cardiomyocyte proliferation and subsequent cardiac recovery post MI. Conversely, locked nucleic acid-based anti-miR-34a treatment diminished post-MI miR-34a upregulation in adult hearts and significantly improved post-MI remodeling. In isolated cardiomyocytes, we found that miR-34a directly regulated cell cycle activity and death via modulation of its targets, including Bcl2, Cyclin D1, and Sirt1. CONCLUSIONS: miR-34a is a critical regulator of cardiac repair and regeneration post MI in neonatal hearts. Modulation of miR-34a may be harnessed for cardiac repair in adult myocardium.


Asunto(s)
Corazón/fisiología , MicroARNs/fisiología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Regeneración/fisiología , Animales , Animales Recién Nacidos , Femenino , Masculino , Ratones , Miocitos Cardíacos/patología , Miocitos Cardíacos/fisiología , Embarazo
7.
Circ J ; 81(6): 870-878, 2017 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-28216514

RESUMEN

BACKGROUND: Hydrogen sulfide (H2S) exerts beneficial actions against the development of cardiovascular disease. Diallyl trisulfide (DATS) is an organic polysulfide found in garlic oil that liberates H2S under physiological conditions. This study investigated whether DATS modulates endothelial cell function, as well as revascularization processes in a mouse model of hind-limb ischemia.Methods and Results:Wild-type (WT), endothelial nitric oxide synthase-deficient (eNOS-KO) and Akt1-heterogenic deficient (Akt-Het) mice were subjected to unilateral hindlimb ischemia (HLI). DATS or a vehicle control was injected into the abdomen of mice for up to 10 days following HLI induction. Treatment with DATS enhanced blood flow recovery and capillary density in the ischemic limbs of WT mice. This was accompanied by a reduction in apoptotic activity and oxidative stress in the ischemic muscles. DATS also increased the phosphorylation of Akt and eNOS in ischemic muscles. In contrast to WT mice, DATS did not improve blood flow of eNOS-KO and Akt-Het mice. In cultured human umbilical vein endothelium cells, DATS decreased apoptotic activity and oxidative stress under hypoxic conditions, and stimulated the phosphorylation of Akt and eNOS. Inhibition of Akt or NOS signaling reversed DATS-stimulated eNOS phosphorylation and blocked the effects of DATS on apoptosis and oxidative stress. CONCLUSIONS: These observations suggest that DATS promotes revascularization in response to HLI through its ability to stimulate the Akt-eNOS signaling pathway.


Asunto(s)
Compuestos Alílicos/farmacología , Células Endoteliales/enzimología , Miembro Posterior/irrigación sanguínea , Isquemia/enzimología , Neovascularización Fisiológica/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Transducción de Señal/efectos de los fármacos , Sulfuros/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Células Endoteliales/patología , Miembro Posterior/patología , Isquemia/tratamiento farmacológico , Isquemia/genética , Isquemia/patología , Masculino , Ratones , Ratones Noqueados , Óxido Nítrico Sintasa de Tipo III/genética , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética
8.
Circ Res ; 112(1): 27-34, 2013 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-23136123

RESUMEN

RATIONALE: After cardiac injury, cardiac progenitor cells are acutely reduced and are replenished in part by regulated self-renewal and proliferation, which occurs through symmetric and asymmetric cellular division. Understanding the molecular cues controlling progenitor cell self-renewal and lineage commitment is critical for harnessing these cells for therapeutic regeneration. We previously have found that the cell surface ATP-binding cassette G-subfamily transporter 2 (Abcg2) influences the proliferation of cardiac side population (CSP) progenitor cells, but through unclear mechanisms. OBJECTIVE: To determine the role of Abcg2 on cell cycle progression and mode of division in mouse CSP cells. METHODS AND RESULTS: Herein, using CSP cells isolated from wild-type and Abcg2 knockout mice, we found that Abcg2 regulates G1-S cell cycle transition by fluorescence ubiquitination cell cycle indicators, cell cycle-focused gene expression arrays, and confocal live-cell fluorescent microscopy. Moreover, we found that modulation of cell cycle results in transition from symmetric to asymmetric cellular division in CSP cells lacking Abcg2. CONCLUSIONS: Abcg2 modulates CSP cell cycle progression and asymmetric cell division, establishing a mechanistic link between this surface transporter and cardiac progenitor cell function. Greater understanding of progenitor cell biology and, in particular, the regulation of resident progenitor cell homeostasis is vital for guiding the future development of cell-based therapies for cardiac regeneration.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , División Celular Asimétrica , Puntos de Control del Ciclo Celular , Miocardio/metabolismo , Células de Población Lateral/metabolismo , Transducción de Señal , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/deficiencia , Transportadoras de Casetes de Unión a ATP/genética , Animales , División Celular Asimétrica/genética , Puntos de Control del Ciclo Celular/genética , Células Cultivadas , Citometría de Flujo , Puntos de Control de la Fase G1 del Ciclo Celular , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Genes Reporteros , Cinética , Masculino , Ratones , Ratones Noqueados , Microscopía Confocal , Microscopía Fluorescente , Microscopía por Video , Miocardio/citología , Interferencia de ARN , Transducción de Señal/genética , Imagen de Lapso de Tiempo , Transfección
9.
Circ Res ; 112(9): 1253-62, 2013 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-23463815

RESUMEN

RATIONALE: Multiple progenitors derived from the heart and bone marrow (BM) have been used for cardiac repair. Despite this, not much is known about the molecular identity and relationship among these progenitors. To develop a robust stem cell therapy for the heart, it is critical to understand the molecular identity of the multiple cardiogenic progenitor cells. OBJECTIVE: This study is the first report of high-throughput transcriptional profiling of cardiogenic progenitor cells carried out on an identical platform. METHOD AND RESULTS: Microarray-based transcriptional profiling was carried out for 3 cardiac (ckit(+), Sca1(+), and side population) and 2 BM (ckit(+) and mesenchymal stem cell) progenitors, obtained from age- and sex-matched wild-type C57BL/6 mice. Analysis indicated that cardiac-derived ckit(+) population was very distinct from Sca1(+) and side population cells in the downregulation of genes encoding for cell-cell and cell-matrix adhesion proteins, and in the upregulation of developmental genes. Significant enrichment of transcripts involved in DNA replication and repair was observed in BM-derived progenitors. The BM ckit(+) cells seemed to have the least correlation with the other progenitors, with enrichment of immature neutrophil-specific molecules. CONCLUSIONS: Our study indicates that cardiac ckit(+) cells represent the most primitive population in the rodent heart. Primitive cells of cardiac versus BM origin differ significantly with respect to stemness and cardiac lineage-specific genes, and molecules involved in DNA replication and repair. The detailed molecular profile of progenitors reported here will serve as a useful reference to determine the molecular identity of progenitors used in future preclinical and clinical studies.


Asunto(s)
Células de la Médula Ósea/metabolismo , Diferenciación Celular , Linaje de la Célula , Células Madre Mesenquimatosas/metabolismo , Miocitos Cardíacos/metabolismo , Células Madre/metabolismo , Animales , Antígenos Ly/metabolismo , Biomarcadores/metabolismo , Adhesión Celular/genética , Comunicación Celular/genética , Diferenciación Celular/genética , Linaje de la Célula/genética , Células Cultivadas , Reparación del ADN/genética , Replicación del ADN/genética , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Separación Inmunomagnética , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Fenotipo , Proteínas Proto-Oncogénicas c-kit/metabolismo , ARN Mensajero/metabolismo , Transducción de Señal/genética
10.
Circ Res ; 110(10): 1355-63, 2012 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-22581921

RESUMEN

Over the past decade, extensive work in animal models and humans has identified the presence of adult cardiac progenitor cells, capable of cardiomyogenic differentiation and likely contributors to cardiomyocyte turnover during normal development and disease. Among cardiac progenitor cells, there is a distinct subpopulation, termed "side population" (SP) progenitor cells, identified by their unique ability to efflux DNA binding dyes through an ATP-binding cassette transporter. This review highlights the literature on the isolation, characterization, and functional relevance of cardiac SP cells. We review the initial discovery of cardiac SP cells in adult myocardium as well as their capacity for functional cardiomyogenic differentiation and role in cardiac regeneration after myocardial injury. Finally, we discuss recent advances in understanding the molecular regulators of cardiac SP cell proliferation and differentiation, as well as likely future areas of investigation required to realize the goal of effective cardiac regeneration.


Asunto(s)
Células Madre Adultas/fisiología , Cardiopatías/fisiopatología , Corazón/fisiología , Miocardio/citología , Regeneración/fisiología , Células de Población Lateral/citología , Animales , Diferenciación Celular , Proliferación Celular , Cardiopatías/terapia , Humanos
11.
JACC Cardiovasc Imaging ; 17(1): 45-58, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37452820

RESUMEN

BACKGROUND: Fluorodeoxyglucose positron emission tomography (18F-FDG-PET) can noninvasively assess active inflammatory myocardium in patients with cardiac sarcoidosis (CS). Prednisolone (PSL) is the initial drug of choice for active CS; however, its efficacy has not been prospectively evaluated. Moreover, there are no alternative systematic treatment strategies. OBJECTIVES: The goal of this study was to evaluate the efficacy of methotrexate (MTX) in patients refractory to PSL assessed by using cardiac metabolic activity (CMA) in 18F-FDG-PET. METHODS: A total of 59 patients with active CS were prospectively enrolled. CMA (standardized uptake value × accumulation area) was used as an indicator of active inflammation, and a 6-month regimen of PSL therapy was introduced, followed by a second FDG scan. Poor responders to PSL therapy (CMA reduction rate <70%) and patients with recurrent CS (CMA reduction rate ≥70% after initial PSL therapy but CMA recurred after an additional 6 months of therapy) were randomly assigned to the MTX or repeat PSL (re-PSL) therapy groups for another 6 months. RESULTS: Fifty-six patients completed the initial 6-month PSL therapy regimen. Median CMA reduced from 203.3 to 1.0 (P < 0.001), and 47 patients were allocated to the response group, 9 to the poor response group, and 2 to the recurrent group. Accordingly, 11 patients were randomly assigned to the MTX (n = 5) or re-PSL (n = 6) groups. After 6 months, neither group showed a significant reduction in CMA values. MTX was comparable to re-PSL in reducing CMA. CONCLUSIONS: The 6-month regimen of PSL was a potent therapeutic tool for active CS. When MTX was added to low-dose PSL in patients refractory to the initial PSL therapy, there was no significant difference compared with re-PSL. Further studies are needed to evaluate the therapeutic potential of MTX for active CS, including how MTX works when it is administered in higher doses or for longer periods.


Asunto(s)
Cardiomiopatías , Miocarditis , Sarcoidosis , Humanos , Fluorodesoxiglucosa F18 , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/tratamiento farmacológico , Radiofármacos , Valor Predictivo de las Pruebas , Miocardio/metabolismo , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/metabolismo , Tomografía de Emisión de Positrones/métodos , Terapia de Inmunosupresión
12.
Eur Heart J Open ; 3(2): oead028, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37026023

RESUMEN

Aims: Coronary microvascular dysfunction (CMD) is related to the pathophysiology, mortality, and morbidity of heart failure with preserved ejection fraction (HFpEF). A novel single-photon emission computed tomography (SPECT) camera with cadmium zinc telluride (CZT) detectors allows for the quantification of absolute myocardial blood flow and myocardial flow reserve (MFR) in patients with coronary artery disease. However, the potential of CZT-SPECT assessing for CMD has never been evaluated in patients with HFpEF. Methods and results: The clinical records of 127 consecutive patients who underwent dynamic CZT-SPECT were retrospectively reviewed. Rest and stress scanning were started simultaneously with 3 and 9 MBq/kg of 99mTc-sestamibi administration, respectively. Dynamic CZT-SPECT imaging data were analysed using a net-retention model with commercially available software. Transthoracic echocardiography was performed in all patients. The MFR value was significantly lower in the HFpEF group (mean ± SEM = 2.00 ± 0.097) than that in the non-HFpEF group (mean ± SEM = 2.74 ± 0.14, P = 0.0004). A receiver operating characteristic analysis indicated that if a cut-off value of 2.525 was applied, MFR could efficiently distinguish HFpEF from non-HFpEF. Heart failure with preserved ejection fraction had a consistently low MFR, regardless of the diastolic dysfunction score. Heart failure with preserved ejection fraction patients with MFR values lower than 2.075 had a significantly higher incidence of heart failure exacerbation. Conclusion: Myocardial flow reserve assessed by CZT-SPECT was significantly reduced in patients with HFpEF. A lower MFR was associated with a higher hospitalization rate in these patients. Myocardial flow reserve assessed by CZT-SPECT has the potential to predict future adverse events and stratify the severity of disease in patients with HFpEF.

13.
iScience ; 25(7): 104651, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35811849

RESUMEN

It is widely accepted that adipose-derived regenerative cells (ADRCs) can differentiate into mesodermal lineage cells. However, reprogramming adult ADRCs into mature cardiomyocytes is challenging. We investigated the induction of myocardial differentiation in ADRCs via direct reprogramming using lentiviral gene transfer. First, we identified candidate transcriptional factors by performing RNA sequencing and ultimately confirmed that the combination of six unique factors (Baf60c, Gata4, Gata6, Klf15, Mef2a, and Myocd) could efficiently express enhanced green fluorescent protein (GFP) in ADRCs isolated from adult alpha-myosin heavy chain promoter-driven GFP transgenic mice. The GFP-positive ADRCs induced by six factors (6F-ADRCs) expressed multiple cardiac genes and revealed cardiac differentiation in bioinformatic analysis. Moreover, injection of 6F-ADRCs into acute myocardial infarcted tissues in vivo resulted in the improvement of survival rate, fractional shortening, and reduction of infarction scar area. This study provides an alternative method for direct reprogramming of adult ADRCs into cardiomyocytes.

14.
J Nucl Cardiol ; 17(6): 1082-90, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20635229

RESUMEN

BACKGROUND: We sought to determine the relationship between (99m)Tc-sestamibi washout and myocardial properties in hypertrophic cardiomyopathy (HCM) patients. METHODS AND RESULTS: Twenty-four HCM patients underwent biventricular cardiac catheterization, with a micromanometer-tipped catheter, both at rest and during atrial pacing, echocardiography and myocardial (99m)Tc-sestamibi scintigraphy at rest. The (99m)Tc-sestamibi washout rate (WR) was calculated using initial and delayed planar images. The HCM patients were divided into two groups as follows: Group A consisted of 13 patients showing (99m)Tc-sestamibi WR < 22.5%; group B of 11 patients showing (99m)Tc-sestamibi WR ≥ 22.5%. Significant correlations were observed between (99m)Tc-sestamibi WR and percentage changes in pressure half-time (T (1/2)), as well as those in the maximum first derivative LV pressure (LV dP/dt (max)) (r = .43, P = .033; r = -.63, P = .001). The percentage changes in LV dP/dt (max) and those in T (1/2) were significantly more reduced in group B than in group A (P < .05). The biphasic force-frequency relation was more frequently observed in group B than in group A (82% vs. 18%). CONCLUSION: Increased (99m)Tc-sestamibi washout is associated with an impaired contractile reserve and prolonged relaxation, suggesting that myocardial (99m)Tc-sestamibi scintigraphy may be useful in noninvasively detecting the early impairment of myocardial function in HCM patients.


Asunto(s)
Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/diagnóstico , Miocardio/patología , Anciano , Cardiomiopatía Hipertrófica/patología , Ecocardiografía/métodos , Femenino , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Presión , Pronóstico , Cintigrafía , Tecnecio Tc 99m Sestamibi
15.
Clin Exp Pharmacol Physiol ; 37(10): 1004-9, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20626415

RESUMEN

1. To date, few prognostic indicators for ambulatory patients with idiopathic dilated cardiomyopathy (IDCM) have been identified. The purpose of the present study was to investigate the relationship between the occurrence of dobutamine-induced mechanical alternans (MA) and prognosis in ambulatory patients with IDCM. 2. Left ventricular pressure was measured during right atrial pacing and after intravenous infusion of dobutamine at incremental doses in 90 ambulatory patients with IDCM in sinus rhythm. Endomyocardial biopsy specimens were also obtained for quantitative analysis of gene expression. The patients were followed up for a mean of 2.5 years. 3. Patients were classified into three groups: (i) 60 patients who exhibited neither pacing- nor dobutamine-induced MA (Group N); (ii) 20 patients who manifested only pacing-induced MA (Group P); and (iii) 10 patients who developed both pacing- and dobutamine-induced MA (Group D). The sarcoplasmic/endoplasmic reticulum calcium ATPase 2a:phospholamban mRNA ratio was significantly higher in Group D patients than in patients in Groups N or P. Multivariate analysis revealed that dobutamine-induced MA (odds ratio 4.05; 95% confidence interval 1.35-12.2) was a significant independent predictor of cardiac events. Cardiac event-free survival in Group D was significantly lower than in Groups N or P, as determined by Kaplan-Meier analysis (P=0.002). 4. The occurrence of dobutamine-induced MA is a potentially useful clinical predictor of poor prognosis in ambulatory patients with IDCM in sinus rhythm.


Asunto(s)
Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/fisiopatología , Dobutamina , Ecocardiografía de Estrés/métodos , Prueba de Esfuerzo/métodos , Adulto , Anciano , Cateterismo Cardíaco/efectos de los fármacos , Cateterismo Cardíaco/métodos , Dobutamina/farmacología , Ecocardiografía de Estrés/efectos de los fármacos , Prueba de Esfuerzo/efectos de los fármacos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Función Ventricular Izquierda/fisiología , Adulto Joven
16.
Eur Heart J ; 30(15): 1853-62, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19468012

RESUMEN

AIMS: To examine the relation between mitochondrial dysfunction and myocardial contractile and relaxation reserves in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: Thirty HCM patients (LVEF >or=60%) underwent biventricular cardiac catheterization analysis both at rest and during atrial pacing as well as myocardial (99m)Tc-sestamibi scintigraphy at rest to calculate washout rate. Endomyocardial biopsy specimens were obtained for quantitative mRNA analysis and electron microscopy. The HCM patients were divided into two groups-group A: normal force-frequency relation and a pressure half-time (T(1/2)) of <30 ms (n = 15); group B: abnormal force-frequency relation or T(1/2) of >or=30 ms (n = 15). The (99m)Tc-sestamibi washout rate was significantly correlated with T(1/2) for all patients (r = 0.74, P < 0.01) and was also significantly greater in group B (29.2 +/- 6.3%) than in group A (19.3 +/- 3.1%). The abundance of mRNAs for mitochondrial electron transport-related enzymes was significantly higher in group A than in group B. Mitochondria showed a greater variation in size and were more disorganized in group B than in group A. CONCLUSION: Mitochondria showed functional impairment and morphological disorganization in the left ventricle of HCM patients without baseline systolic dysfunction. These mitochondrial changes were associated with impaired myocardial contractile and relaxation reserves.


Asunto(s)
Cardiomiopatía Hipertrófica/fisiopatología , Mitocondrias Cardíacas/fisiología , Contracción Miocárdica/fisiología , Disfunción Ventricular Izquierda/fisiopatología , Cateterismo Cardíaco , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias Cardíacas/diagnóstico por imagen , Mitocondrias Cardíacas/patología , Imagen de Perfusión Miocárdica/métodos , Descanso/fisiología , Ultrasonografía , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/patología
17.
Sci Rep ; 10(1): 16045, 2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32994527

RESUMEN

Adipose-derived regenerative cell (ADRC) is a promising alternative source of autologous somatic stem cells for the repair of damaged tissue. This study aimed to assess the safety and feasibility of autologous ADRC implantation for therapeutic angiogenesis in patients with critical limb ischaemia (CLI). A clinical pilot study-Therapeutic Angiogenesis by Cell Transplantation using ADRCs (TACT-ADRC) study-was initiated in Japan. Adipose tissue was obtained by ordinary liposuction method. Isolated ADRCs were injected into the ischaemic limb. We performed TACT-ADRC procedure in five patients with CLI. At 6 months, no adverse events related to the TACT-ADRC were observed. No patients required major limb amputation, and ischaemic ulcers were partly or completely healed during the 6-month follow-up. In all cases, significant clinical improvements were seen in terms of rest pain and 6-min walking distance. Numbers of circulating CD34+ and CD133+ cells markers of progenitor cell persistently increased after ADRC implantation. The ratio of VEGF-A165b (an anti-angiogenic isoform of VEGF) to total VEGF-A in plasma significantly decreased after ADRC implantation. In vitro experiments, cultured with ADRC-conditioned media (CM) resulted in increased total VEGF-A and decreased VEGF-A165b in C2C12 cells, but not in macrophages. ADRC-CM also increased CD206+ cells expression and decreased TNF-α in macrophages. Autologous ADRC implantation was safe and effective in patients with CLI and could repair damaged tissue via its ability to promote angiogenesis and suppress tissue inflammation.


Asunto(s)
Isquemia/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Trasplante Autólogo/métodos , Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Adulto , Anciano , Inductores de la Angiogénesis/uso terapéutico , Femenino , Humanos , Japón , Masculino , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Neovascularización Fisiológica/fisiología , Enfermedad Arterial Periférica/complicaciones , Proyectos Piloto , Regeneración/fisiología , Trasplante de Células Madre/métodos , Tromboangitis Obliterante/complicaciones
18.
Can J Cardiol ; 36(10): 1649-1657, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32615071

RESUMEN

BACKGROUND: Delirium is a common adverse event observed in patients admitted to the intensive care unit (ICU). However, the prognostic value of delirium and its determinants have not been thoroughly investigated in patients with acute heart failure (AHF). METHODS: We investigated 408 consecutive patients with AHF admitted to the ICU. Delirium was diagnosed by means of the Confusion Assessment Method for ICU tool and evaluated every 8 hours during the patients' ICU stays. RESULTS: Delirium occurred in 109 patients (26.7%), and the in-hospital mortality rate was significantly higher in patients with delirium (13.8% vs 2.3%; P < 0.001). Multivariate logistic regression analysis showed that delirium independently predicted in-hospital mortality (odds ratio [OR] 4.33, confidence interval [CI] 1.62-11.52; P = 0.003). Kaplan-Meier analysis showed that the 12-month mortality rate was significantly higher in patients with delirium compared with those without (log-rank test: P < 0.001), and Cox proportional hazards analysis showed that delirium remained an independent predictor of 12-month mortality (hazard ratio 2.19, 95% CI 1.49-3.25; P < 0.001). The incidence of delirium correlated with severity of heart failure as assessed by means of the Get With The Guidelines-Heart Failure risk score (chi-square test: P = 0.003). Age (OR 1.05, 95% CI 1.02-1.09; P = 0.003), nursing home residential status (OR 3.32, 95% CI 1.59-6.94; P = 0.001), and dementia (OR 5.32, 95% CI 2.83-10.00; P < 0.001) were independently associated with the development of delirium. CONCLUSIONS: Development of delirium during ICU stay is associated with short- and long-term mortality and is predicted by the severity of heart failure, nursing home residential, and dementia status.


Asunto(s)
Delirio , Insuficiencia Cardíaca , Unidades de Cuidados Intensivos/estadística & datos numéricos , Pronóstico , Anciano , Cuidados Críticos/métodos , Cuidados Críticos/estadística & datos numéricos , Delirio/diagnóstico , Delirio/epidemiología , Delirio/etiología , Demencia/epidemiología , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/psicología , Insuficiencia Cardíaca/terapia , Mortalidad Hospitalaria , Humanos , Incidencia , Japón/epidemiología , Estimación de Kaplan-Meier , Masculino , Casas de Salud/estadística & datos numéricos , Factores de Riesgo , Índice de Severidad de la Enfermedad
19.
Cardiovasc Revasc Med ; 21(10): 1220-1227, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32457019

RESUMEN

BACKGROUND: High-risk percutaneous coronary intervention (PCI) in patients with left ventricular (LV) systolic dysfunction has been proven to induce reverse LV remodeling. However, the impact of high-risk PCI focusing on rotational atherectomy (RA) in patients with severe LV systolic dysfunction has not been completely addressed. METHODS: Among 4339 consecutive patients who underwent PCI, 178 patients with 192 lesions were treated with RA. The reduced ejection fraction (EF) group (LVEF ≤35%) included 25 patients, the mid-range EF group (LVEF 36-50%) included 44 patients, and the preserved EF group (LVEF >50%) included 109 patients. The primary outcome was a composite of cardiac death, non-fatal myocardial infarction, target-vessel revascularization, and ischemic stroke. RESULTS: The cumulative 1-year incidence of the primary outcome was similar among the three groups (reduced EF, 29%; mid-range EF, 25%; preserved EF, 26%; p = 0.95). After adjusting for confounding factors, the incidence of the primary outcome in the reduced EF group (hazard ratio [HR], 1.07; 95% confidence interval [CI], 0.43-2.37; p = 0.87) and the mid-range EF group (HR, 0.99; 95% CI, 0.47-1.94; p = 0.97) was similar to that in the preserved EF group. LVEF was significantly improved in the reduced EF and mid-range EF groups compared with the preserved EF group (absolute change in LVEF: 13.6 ± 11.3%, 9.0 ± 10.1%, and -0.7 ± 7.8%, respectively; p < 0.0001). CONCLUSIONS: Reduced EF was not associated with increase in the primary outcome in patients undergoing RA. This seemed to result from the improved LV function after PCI. SUMMARY FOR ANNOTATED TABLE OF CONTENTS: This single center analysis study investigated 1-year composite outcome of cardiac death, non-fatal myocardial infarction, target-vessel revascularization, and ischemic stroke in patients with severe LV systolic dysfunction undergoing RA compared with that in patients with preserved LV function. The cumulative 1-year incidence of the composite outcome was similar among the three groups (reduced EF, 29%; mid-range EF, 25%; preserved EF, 26%; p = 0.95). LVEF was significantly improved in the reduced EF and mid-range EF groups compared with the preserved EF group (absolute change in LVEF: 13.6 ± 11.3%, 9.0 ± 10.1%, and -0.7 ± 7.8%, respectively; p < 0.0001).


Asunto(s)
Aterectomía Coronaria , Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Disfunción Ventricular Izquierda , Humanos , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico , Resultado del Tratamiento , Función Ventricular Izquierda
20.
J Cardiovasc Pharmacol ; 54(1): 47-56, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19528815

RESUMEN

OBJECTIVE: To investigate the mechanism responsible for the increased cardiac stiffness associated with hypertensive heart failure in Dahl salt-sensitive (DS) rats and the effects of treatment with the combination of a calcium channel blocker [azelnidipine (AZE)] and angiotensin II type 1 receptor blocker [olmesartan (OLM)]. METHODS: DS rats fed a high-salt diet from 7 weeks of age were treated (or not) from 12 to 19 weeks of age with the vasodilator hydralazine, OLM plus AZE, or the reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin. Rats fed a low-salt diet served as controls. RESULTS: Treatment with OLM plus AZE attenuated changes in the expression of collagen isoforms and a decrease in the ratio of elastin to collagen in the left ventricle and prevented the increase in myocardial stiffness and diastolic dysfunction in DS rats in a manner independent of the hypotensive effect of these drugs. Such treatment also inhibited the expression and activation of elastolytic proteases (including cathepsins S and K and metalloproteinases-2, -9, and -12), NADPH oxidase-dependent superoxide production, and inflammatory changes in the failing myocardium. All these effects were mimicked by treatment with apocynin. CONCLUSIONS: The changes in collagen isoform expression and the decrease in the elastin to collagen ratio in the failing myocardium likely account for the increase in diastolic stiffness in this model of hypertensive heart failure. Administration of angiotensin receptor and calcium channel blockers prevented these changes in a manner independent of the hypotensive effect of these drugs by inhibiting the increase in elastolytic activity induced by activation of NADPH oxidase.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Insuficiencia Cardíaca/metabolismo , Miocardio/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Animales , Ácido Azetidinocarboxílico/análogos & derivados , Ácido Azetidinocarboxílico/farmacología , Diástole/efectos de los fármacos , Diástole/fisiología , Dihidropiridinas/farmacología , Imidazoles/farmacología , Masculino , Ratas , Ratas Endogámicas Dahl , Tetrazoles/farmacología
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