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1.
Am J Chin Med ; 45(2): 255-268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28231740

RESUMO

The aim of this study was to determine the effect of combination therapy consisting of acupuncture and traditional herbal medicine (Kampo medicine) for reducing the incidence rate of delirium in patients with cardiovascular (CV) disease in ICUs. Twenty-nine patients who had been urgently admitted to the ICU in the control period were treated with conventional intensive care. Thirty patients in the treatment period received conventional therapy plus a combination therapy consisting of acupuncture and herbal medicine. Acupuncture treatment was performed once a day, and the herbal formula was administered orally three times a day during the first week of the ICU stay. The standard acupuncture points were GV20, Ex-HN3, HT7, LI4, Liv3, and KI3, and the main herbal preparation was Kamikihito. The incident rates of delirium, assessed using the confusion assessment method for ICU, in the treatment and control period were compared. The incidence rate of delirium was significantly lower in the treatment group than in the control group (6.6% vs. 37.9%, [Formula: see text]). Moreover, sedative drugs and non-pharmacological approaches against aggressive behavior of patients who were delirious were used less in the treatment group than in the control group. No serious adverse events were observed in the treatment group. Combination therapy consisting of acupuncture and herbal medicine was found to be effective in lowering the incidence of delirium in patients with CV disease in ICUs. Further studies with a large sample size and parallel randomized controlled design would be required to establish the effects of this therapy.


Assuntos
Terapia por Acupuntura , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/terapia , Delírio/etiologia , Delírio/prevenção & controle , Medicamentos de Ervas Chinesas/administração & dosagem , Unidades de Terapia Intensiva , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Agressão , Terapia Combinada , Delírio/epidemiologia , Delírio/psicologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
2.
J Cardiol Cases ; 16(5): 178-182, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30279829

RESUMO

During electron microscopic examination of 156 consecutive human endomyocardial biopsy specimens, we found marked mitochondrial deformity within a single cardiomyocyte in each of 4 specimens. The deformed mitochondria were unevenly distributed, but the deformities were confined to the one cardiomyocyte. Those affected cardiomyocytes were accompanied by nonspecific degenerative changes such as nuclear hypertrophy and/or rarefaction of the myofibrils. Mitochondria in all other cells within the specimens appeared normal. Such an abnormality has never been reported to date. Each of the four cases was diagnosed with a different ailment: post-myocarditis, dilated cardiomyopathy, amyloidosis, and tachycardia-induced heart failure. However, all four cases were accompanied by left ventricular systolic dysfunction at biopsy. The very limited mitochondrial deformation may thus reflect a type of degenerative change that accompanies heart failure. .

3.
Heart Vessels ; 31(1): 29-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25217036

RESUMO

Recently, a new generation of multi-detector row computed tomography (CT) with 320-detector rows (DR) has become available in the clinical settings. The purpose of the present study was to determine the cutoff values of Hounsfield unit (HU) for discrimination of plaque components by comparing HU of coronary plaques with integrated backscatter intravascular ultrasound (IB-IVUS) serving as a gold standard. Seventy-seven coronary atherosclerotic lesions in 77 patients with angina were visualized by both 320-DR CT (Aquilion One, Toshiba, Japan) and IB-IVUS at the same site. To determine the thresholds for discrimination of plaque components, we compared HU with IB values as a gold standard. Optimal thresholds were determined from receiver operating characteristic (ROC) curves analysis. The HU values of lipid pool (n = 115), fibrosis (n = 93), vessel lumen and calcification (n = 73) were 28 ± 19 HU (range -18 to 69 HU), 98 ± 31 HU (44 to 195 HU), 357 ± 65 HU (227 to 534 HU) and 998 ± 236 HU (366 to 1,489 HU), respectively. The thresholds of 56 HU, 210 HU and 490 HU were the most reliable predictors of lipid pool, fibrosis, vessel lumen and calcification, respectively. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS (r = 0.63, p < 0.05), whereas fibrous volume measured by 320-DR CT was not. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS, whereas fibrous volume was not correlated with that measured by IB-IVUS because manual exclusion of the outside of vessel hindered rigorous discrimination between fibrosis and extravascular components.


Assuntos
Angina Pectoris/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Calcinose , Angiografia Coronária/métodos , Estudos de Viabilidade , Feminino , Fibrose , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Curva ROC , Índice de Gravidade de Doença , Ultrassonografia de Intervenção/métodos
4.
Am J Pathol ; 176(2): 687-98, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20035047

RESUMO

Activation of Fas signaling is a key mediator of doxorubicin cardiotoxicity, which involves both cardiomyocyte apoptosis and myocardial inflammation. In this study, acute cardiotoxicity was induced in mice by doxorubicin, and some mice simultaneously received an intramuscular injection of adenoviral vector encoding mouse soluble Fas (sFas) gene (Ad.CAG-sFas), an inhibitor of Fas/Fas ligand interaction. Two weeks later, left ventricular dilatation and dysfunction were apparent in the LacZ-treated control group, but both were significantly mitigated in the sFas-treated group. The in situ nick-end labeling-positive rate were similar in the two groups, and although electron microscopy revealed cardiomyocyte degeneration, no apoptotic structural features and no activation of caspases were detected, suggesting an insignificant role of apoptosis in this model. Instead, sFas treatment reversed doxorubicin-induced down-regulation of GATA-4 and attenuated ubiquitination of myosin heavy chain and troponin I to preserve these sarcomeric proteins. In addition, doxorubicin-induced significant leukocyte infiltration, fibrosis, and oxidative damage to the myocardium, all of which were largely reversed by sFas treatment. sFas treatment also suppressed doxorubicin-induced p53 overexpression, phosphorylation of c-Jun N-terminal kinase, c-Jun, and inhibitor of nuclear factor-kappaB, as well as production of cyclooxygenase-2 and monocyte chemoattractant protein-1, and it restored extracellular signal-regulated kinase activation. Therefore, sFas gene therapy prevents the progression of doxorubicin-induced acute cardiotoxicity, with accompanying attenuation of the cardiomyocyte degeneration, inflammation, fibrosis, and oxidative damage caused by Fas signaling.


Assuntos
Apoptose/fisiologia , Doxorrubicina , Terapia Genética/métodos , Cardiopatias/induzido quimicamente , Cardiopatias/terapia , Receptor fas/genética , Animais , Apoptose/genética , Dano ao DNA/genética , Ecocardiografia , Fibrose Endomiocárdica/genética , Fibrose Endomiocárdica/patologia , Fibrose Endomiocárdica/prevenção & controle , Cardiopatias/genética , Cardiopatias/patologia , Inflamação/genética , Inflamação/patologia , Óperon Lac , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miocárdio/patologia , Miocárdio/ultraestrutura , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Solubilidade , Receptor fas/antagonistas & inibidores
5.
Am J Physiol Heart Circ Physiol ; 296(3): H616-26, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19151252

RESUMO

We hypothesized that therapy, composed of antiapoptotic soluble Fas (sFas) gene transfer, combined with administration of the cardioprotective cytokine granulocyte colony-stimulating factor (G-CSF), would markedly mitigate cardiac remodeling and dysfunction following myocardial infarction (MI). On the 3rd day after MI induced by ligating the left coronary artery in mice, four different treatments were initiated: saline injection (Group C, n = 26); G-CSF administration (Group G, n = 27); adenoviral transfer of sFas gene (Group F, n = 26); and the latter two together (Group G+F, n = 26). Four weeks post-MI, Group G+F showed better survival than Group C (96 vs. 65%, P < 0.05) and the best cardiac function among the four groups. In Group G, the infarct scar was smaller and less fibrotic, whereas in Group F the scar was thicker, without a reduction in area, and contained abundant myofibroblasts and vascular cells; Group G+F showed both phenotypes. G-CSF exerted a beneficial effect on infarct tissue dynamics through antifibrotic and proliferative effects on granulation tissue; however, it also exerts an adverse proapoptotic effect that leads to thinning of the infarct scar. sFas appeared to offset the latter drawback. In vitro study using cultured myofibroblasts derived from the infarct tissue revealed that G-CSF increased proliferating activity of those cells accompanying activation of Akt and signal transducer and activator of transcription 3, while accelerating Fas-mediated apoptosis with increasing Bax-to-Bcl-2 ratio. The results suggest that combined use of G-CSF administration and sFas gene therapy is a potentially powerful tool against post-MI heart failure.


Assuntos
Apoptose , Cardiotônicos/farmacologia , Técnicas de Transferência de Genes , Terapia Genética , Fator Estimulador de Colônias de Granulócitos/farmacologia , Insuficiência Cardíaca/terapia , Infarto do Miocárdio/terapia , Miocárdio/patologia , Receptor fas/genética , Adenoviridae/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Terapia Combinada , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Fibrose , Vetores Genéticos , Tecido de Granulação/efeitos dos fármacos , Tecido de Granulação/patologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Lenograstim , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Recombinantes/farmacologia , Regeneração/efeitos dos fármacos , Regeneração/genética , Fatores de Tempo , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/terapia , Remodelação Ventricular/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Receptor fas/metabolismo
6.
Am J Physiol Heart Circ Physiol ; 295(4): H1599-607, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18708438

RESUMO

Autophagy is simultaneously a mode of programmed cell death and an important physiological process for cell survival, but its pathophysiological significance in cardiac myocytes remains largely unknown. We induced autophagy in isolated adult rat ventricular cardiomyocytes (ARVCs) by incubating them in glucose-free, mannitol-supplemented medium for up to 4 days. Ultrastructurally, intracellular vacuoles containing degenerated subcellular organelles (e.g., mitochondria) were markedly apparent in the glucose-starved cells. Microtubule-associated protein-1 light chain 3 was significantly upregulated among the glucose-starved ARVCs than among the controls. After 4 days, glucose-starved ARVCs showed a significantly worse survival rate (19+/-5.2%) than the controls (55+/-8.3%, P<0.005). Most dead ARVCs in both groups showed features of necrosis, and the rate of apoptosis did not differ between the groups. Two inhibitors of autophagy, 3-methyladenine (3-MA) and leupeptin, significantly and dose-dependently reduced the viability of both control and glucose-starved ARVCs and caused specific morphological alterations; 3-MA reduced autophagic findings, whereas leupeptin greatly increased the numbers and the sizes of vacuoles that contained incompletely digested organelles. The knockdown of the autophagy-related genes with small interfering RNA also reduced the glucose-starved ARVCs viability, but rapamycin, an autophagy enhancer, improved it. Reductions in the ATP content of ARVCs caused by glucose depletion were exacerbated by the inhibitors while attenuated by rapamycin, suggesting that autophagy inhibition might accelerate energy depletion, leading to necrosis. Taken together, our findings suggest that autophagy in cardiomyocytes reflects a prosurvival, compensatory response to stress and that autophagic cardiomyocyte death represents an unsuccessful outcome due to necrosis.


Assuntos
Autofagia , Forma Celular , Glucose/deficiência , Miócitos Cardíacos/ultraestrutura , Vacúolos/ultraestrutura , Adenina/análogos & derivados , Adenina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Leupeptinas/farmacologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Necrose , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Sirolimo/farmacologia , Fatores de Tempo
7.
Circ Res ; 103(1): 98-106, 2008 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-18519944

RESUMO

Although recanalization of the infarct-related artery late after myocardial infarction (MI) is known to reduce both cardiac remodeling and mortality, the mechanisms responsible are not yet fully understood. We compared infarcted rat hearts in which the infarct-related coronary artery was opened 24 hours after infarction (late reperfusion [LR] group) with those having a permanently occluded artery. Left ventricular dilatation and dysfunction were significantly mitigated in the LR group 1, 2, and 4 weeks post-MI. Attributable, in large part, to the greater number of cells present, the infarcted wall was significantly thicker in the LR group, which likely reduced wall stress and mitigated cardiac dysfunction. Granulation tissue cell proliferation was increased to a greater degree in the LR group 4 days post-MI, whereas the incidence of apoptosis was significantly lower throughout the subacute stage (4 days, 1 week, and 2 weeks post-MI), further suggesting preservation of granulation tissue cells contributes to the thick, cell-rich scar. Functionally, myocardial debris was more rapidly removed from the infarcted areas in the LR group during subacute stages, and stouter collagen was more rapidly synthesized in those areas. Direct acceleration of Fas-mediated apoptosis by hypoxia was confirmed in vitro using infarct tissue-derived myofibroblasts. In salvaged cardiomyocytes, degenerative changes, but not apoptosis, were mitigated in the LR group, accompanied by restoration of GATA-4 and sarcomeric protein expression. Along with various mechanisms proposed earlier, the present findings appear to provide an additional pathophysiological basis for the benefits of late reperfusion.


Assuntos
Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica , Miócitos Cardíacos , Remodelação Ventricular , Animais , Apoptose , Proteínas de Transporte/metabolismo , Colágeno/biossíntese , Proteínas do Citoesqueleto , Fibroblastos/metabolismo , Fibroblastos/patologia , Fator de Transcrição GATA4/metabolismo , Humanos , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Reperfusão Miocárdica/métodos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Fatores de Tempo
8.
J Cell Mol Med ; 12(4): 1272-83, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18298650

RESUMO

Although beneficial effects of granulocyte colony-stimulating factor (G-CSF) have been demonstrated on post-myocardia infarction (MI) process, the mechanisms and feasibility are not fully agreed yet. We investigated effects of a long-term treatment with a low-dose G-CSF started 1 day after the onset of MI, on post-infarction process. One day after being made MI by left coronary ligation, mice were given G-CSF (10 microg/kg/day) for 4 weeks. The G-CSF treatment resulted in a significant mitigation of cardiac remodelling and dysfunction. In the G-CSF-treated hearts, the infarcted scar was smaller with less fibrosis and abundant vessels while in the non-infarcted area, hypertrophic cardiomyocytes with attenuated degenerative changes and reduced fibrosis were apparent. These effects were accompanied by activation of signal transducer and activator of transcription 3 (STAT3) and Akt and also by up-regulation of GATA-4, myosin heavy chain and matrix metalloproteinases-2 and -9. Apoptosis of cardiomyocytes appeared insignificant at any stages. Parthenolide, a STAT3 inhibitor, completely abolished the beneficial effects of G-CSF on cardiac function and remodelling with loss of effect on both anti-cardiomyocyte degeneration and anti-fibrosis. In contrast, wortmannin, an Akt inhibitor, did not affect G-CSF-induced benefits despite cancelling vessel increase. In conclusion, treatment with G-CSF at a small dose but for a long duration beneficially affects the post-infarction process possibly through STAT3-mediated anti-cardiomyocyte degeneration and anti-fibrosis, but not through anti-cardiomyocyte apoptosis or Akt-mediated angio-genesis. The findings may also imply a more feasible way of G-CSF administration in the clinical settings.


Assuntos
Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/patologia , Animais , Apoptose/efeitos dos fármacos , Contagem de Células Sanguíneas , Sobrevivência Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Granulócitos/citologia , Granulócitos/efeitos dos fármacos , Testes de Função Cardíaca , Humanos , Janus Quinases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/enzimologia , Miocárdio/ultraestrutura , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Fator Estimulador de Colônias de Granulócitos/metabolismo , Proteínas Recombinantes , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
9.
Am J Physiol Heart Circ Physiol ; 294(2): H1048-57, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18083897

RESUMO

Hepatocyte growth factor (HGF) reportedly exerts beneficial effects on the heart following myocardial infarction and during nonischemic cardiomyopathy, but the precise mechanisms underlying the latter have not been well elucidated. We generated nonischemic cardiomyopathy in mice by injecting them with doxorubicin (15 mg/kg ip). Two weeks later, when cardiac dysfunction was apparent, an adenoviral vector encoding human HGF gene (Ad.CAG-HGF, 1x10(11) particles/mouse) was injected into the hindlimb muscles; LacZ gene served as the control. Left ventricular dilatation and dysfunction normally seen 4 wk after doxorubicin administration were significantly mitigated in HGF-treated mice, as were the associated cardiomyocyte atrophy/degeneration and myocardial fibrosis. Myocardial expression of GATA-4 and a sarcomeric protein, myosin heavy chain, was downregulated by doxorubicin, but the expression of both was restored by HGF treatment. The protective effect of HGF against doxorubicin-induced cardiomyocyte atrophy was confirmed in an in vitro experiment, which also showed that neither cardiomyocyte apoptosis nor proliferation plays significant roles in the present model. Upregulation of c-Met/HGF receptor was noted in HGF-treated hearts. Among the mediators downstream of c-Met, the activation of extracellular signal-regulated kinase (ERK) was reduced by doxorubicin, but the activity was restored by HGF. Levels of transforming growth factor-beta1 and cyclooxygenase-2 did not differ between the groups. Our findings suggest the HGF gene delivery exerts therapeutic antiatrophic/degenerative and antifibrotic effects on myocardium in cases of established cardiac dysfunction caused by doxorubicin. These beneficial effects appear to be related to HGF-induced ERK activation and upregulation of c-Met, GATA-4, and sarcomeric proteins.


Assuntos
Adenoviridae/genética , Antibióticos Antineoplásicos , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/genética , Doxorrubicina , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/fisiologia , Animais , Animais Recém-Nascidos , Western Blotting , Cardiomiopatias/fisiopatologia , Ciclo-Oxigenase 2/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/fisiologia , Vetores Genéticos , Coração/fisiologia , Humanos , Imuno-Histoquímica , Imunoprecipitação , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , Plasmídeos/genética , Proteínas Proto-Oncogênicas c-met/metabolismo
10.
Am J Physiol Heart Circ Physiol ; 293(4): H2271-80, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17644576

RESUMO

Although amlodipine, a long-acting L-type calcium channel blocker, reportedly prevents left ventricular remodeling and dysfunction after myocardial infarction, the mechanism responsible is not yet well understood. Myocardial infarction was induced in mice by ligating the left coronary artery. Treatment of mice with amlodipine (10 mg x kg(-1) x day(-1)), beginning on the third day postinfarction, significantly improved survival and attenuated left ventricular dilatation and dysfunction 4 wk postinfarction compared with treatment with saline or hydralazine. Although infarct sizes did not differ among the groups, the infarcted wall thickness was greater and the infarct segment length was smaller in the amlodipine-treated group, and cellular components, including vessels and myofibroblasts, were abundant within the infarcted area. Ten days postinfarction (the subacute stage), the proliferation of granulation tissue cells in the infarcted area was similar among the groups, but the incidence of apoptosis was significantly lower in the amlodipine-treated group, where Bad, a proapoptotic Bcl-2 family protein, was significantly phosphorylated (inactivated). Calcineurin, which dephosphorylates (activates) Bad, was upregulated in infarcted hearts, but its levels were significantly reduced by amlodipine treatment. In vitro, Fas stimulation augmented calcineurin activity and induced apoptosis among infarct tissue-derived myofibroblasts; both of those effects were strongly inhibited by amlodipine, two other calcium channel blockers (verapamil or nifedipine), and two calcineurin inhibitors (cyclosporin A or FK-506). Amlodipine inhibits Fas-mediated granulation tissue cell apoptosis in infarcted hearts, possibly by attenuating the activities of calcineurin and Bad. These findings may provide new insight into the mechanism by which calcium channel blockers attenuate postinfarction cardiac remodeling and dysfunction.


Assuntos
Anlodipino/farmacologia , Apoptose/efeitos dos fármacos , Calcineurina/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Tecido de Granulação/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Disfunção Ventricular Esquerda/prevenção & controle , Remodelação Ventricular/efeitos dos fármacos , Anlodipino/uso terapêutico , Animais , Inibidores de Calcineurina , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio/metabolismo , Células Cultivadas , Vasos Coronários/cirurgia , Ciclosporina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Tecido de Granulação/metabolismo , Tecido de Granulação/patologia , Tecido de Granulação/fisiopatologia , Hidralazina/farmacologia , Ligadura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/complicações , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Fosforilação , Projetos de Pesquisa , Tacrolimo/farmacologia , Fatores de Tempo , Vasodilatadores/farmacologia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/efeitos dos fármacos , Proteína de Morte Celular Associada a bcl/metabolismo , Receptor fas/metabolismo
11.
Lab Invest ; 87(5): 440-55, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17334414

RESUMO

It is not well-known yet how granulocyte colony-stimulating factor (G-CSF) affects nonischemic cardiomyopathy, though its beneficial effects on acute myocardial infarction are well-established. We hypothesize that G-CSF beneficially might affect nonischemic cardiomyopathy through the direct cardioprotective effects. Here, we show that a single injection of doxorubicin (DOX, 15 mg/kg) induced left ventricular dilatation and dysfunction in mice within 2 weeks, and that these effects were significantly attenuated by human recombinant G-CSF (100 microg/kg/day for 5 days). G-CSF also protected hearts against DOX-induced cardiomyocyte atrophy/degeneration, fibrosis, inflammatory cell infiltration and down regulation of GATA-4 and sarcomeric proteins, myosin heavy chain, troponin I and desmin, both in vivo and in vitro. Cardiac cyclooxygenase-2 was upregulated and G-CSF receptor was downregulated in DOX-induced cardiomyopathy, but both of those effects were largely reversed by G-CSF. No DOX-induced apoptotic effects were seen, nor were there any changes in tumor necrosis factor-alpha or transforming growth factor-beta1 levels. Among downstream mediators of G-CSF receptor signaling, DOX-induced cardiomyopathy involved inactivation of extracellular signal-regulated protein kinase (ERK); the ERK inactivation was reversed by G-CSF. Inhibition of ERK activation, but not cyclooxygenase-2 inhibition, completely abolished beneficial effect of G-CSF on cardiac function. G-CSF did not promote differentiation of bone marrow cells into cardiomyocytes according to the experiment using green fluorescent protein-chimeric mice, and inhibition of CXCR4+ cell homing using AMD3100 did not diminish the effect of G-CSF. Finally, G-CSF was also effective when administered after cardiomyopathy was established. In conclusion, these findings imply the therapeutic usefulness of G-CSF mainly through restoring ERK activation against DOX-induced nonischemic cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/prevenção & controle , Cardiotônicos/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Animais Recém-Nascidos , Antibióticos Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Cardiomiopatia Dilatada/induzido quimicamente , Cardiomiopatia Dilatada/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Doxorrubicina/toxicidade , Combinação de Medicamentos , Quimioterapia Combinada , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/ultraestrutura , Proteínas Recombinantes , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/patologia
12.
J Card Fail ; 13(2): 155-62, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17395057

RESUMO

BACKGROUND: In patients with end-stage renal disease, angiotensin II type 1A receptor (AT1) blockade attenuates the associated cardiac dysfunction. We investigated the molecular signaling mediating that effect. METHODS AND RESULTS: We used 5/6 nephrectomy to induce significant renal dysfunction in AT1 knockout (AT1KO) and wild-type mice (WT). Twelve weeks after nephrectomy, WT showed significant left ventricular dilation and dysfunction that were accompanied by cardiomyocyte hypertrophy, fibrosis, and reduced capillary density. All of these effects were significantly mitigated in AT1KO. Nephrectomy led to upregulation of myocardial expression of AT1, transforming growth factor-beta1 (TGF-beta1), matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and phosphorylated Akt (p-Akt), and also led to increased oxidative damage in cardiomyocytes. In AT1KO, TGF-beta1, TIMP-1, oxidative damage levels were lower, whereas MMPs and p-Akt levels were higher. Treating nephrectomized WT mice with valsartan (an AT1 blocker), but not hydralazine, improved cardiac function and altered molecular signaling in a manner similar to that seen in AT1KO mice. Notably, AT1 expression was downregulated in valsartan-treated but not hydralazine-treated hearts. CONCLUSIONS: These findings provide novel insight into the mechanism underlying the beneficial effects of AT1 blockade on cardiac function in a model of renal dysfunction-associated heart failure.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Insuficiência Cardíaca/etiologia , Falência Renal Crônica/prevenção & controle , Receptor Tipo 1 de Angiotensina/sangue , Transdução de Sinais/fisiologia , Tetrazóis/uso terapêutico , Valina/análogos & derivados , Animais , Nitrogênio da Ureia Sanguínea , Western Blotting , Creatinina/sangue , DNA/genética , Modelos Animais de Doenças , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Imuno-Histoquímica , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Nefrectomia/efeitos adversos , Estresse Oxidativo/genética , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Fator de Crescimento Transformador beta1/genética , Resultado do Tratamento , Regulação para Cima/efeitos dos fármacos , Valina/uso terapêutico , Valsartana , Função Ventricular Esquerda/efeitos dos fármacos
13.
Am J Physiol Heart Circ Physiol ; 292(5): H2184-94, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17208988

RESUMO

Blockade of angiotensin II type 1 receptor (AT1) signaling attenuates heart failure following myocardial infarction (MI), perhaps through reduction of fibrosis in the noninfarcted myocardium. However, its specific effect on the infarct tissue itself has not been fully clarified, which we examined in the present study. After MI induction in mice, treatment with the AT1 blocker olmesartan, beginning on the 3rd day post-MI, significantly improved survival (94%) 4 wk post-MI, compared with saline (53%) and hydralazine (73%). Olmesartan-treated mice also showed significant attenuation of left ventricular dilatation and dysfunction, as well as significantly greater infarct wall thickness, although the absolute size of the infarct scar was unchanged. In addition, significantly greater numbers of nonmyocytes (mainly vascular cells and myofibroblasts) were present within the infarct scar in olmesartan-treated hearts. Ten days post-MI, apoptosis among granulation tissue cells was significantly suppressed in the olmesartan-treated hearts, where expression of Fas, Bax, procaspase-3, and Daxx and activation of caspase-3, c-Jun NH(2)-terminal kinase, and c-Jun were all significantly attenuated. By contrast, expression of Fas ligand, Bcl-2, and Fas-associated death domain and activation of caspase-8 were unaffected, suggesting olmesartan exerts a negative regulatory effect on the alternate pathway downstream of Fas receptor. In vitro, olmesartan dose-dependently inhibited Fas-mediated apoptosis in granulation tissue-derived myofibroblasts. The present study proposes this antiapoptotic effect as another important mechanism for an AT1 blocker in improving post-MI ventricular remodeling, as well as its antifibrotic effect, and also suggests a significant link between renin-angiotensin and Fas/Fas ligand systems in postinfarction hearts.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Imidazóis/farmacologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Tetrazóis/farmacologia , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação Ventricular/efeitos dos fármacos , Receptor fas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/complicações , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia
14.
Am J Physiol Heart Circ Physiol ; 292(2): H946-53, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17028164

RESUMO

Blockade of ANG II type 1A receptor (AT(1A)) is known to attenuate postinfarction [postmyocardial infarction (post-MI)] heart failure, accompanying reduction in fibrosis of the noninfarcted area. In the present study, we investigated the influence of AT(1A) blockade on the infarcted tissue itself. Consistent with earlier reports, AT(1A) knockout (AT(1A)KO) mice showed significantly attenuated left ventricular (LV) remodeling (dilatation) and dysfunction compared with wild-type (WT) mice. Morphometry revealed that the infarcted wall was thicker and had a smaller circumferential length in AT(1A)KO than WT hearts. In addition, significantly greater numbers of cells were present within infarcts in AT(1A)KO hearts 4 wk post-MI; most notably, there was an abundance of vessels and myofibroblasts. One week post-MI, the incidence of apoptosis among granulation tissue cells was fewer (3.3 +/- 0.4 vs. 4.4 +/- 0.5% in WT, P < 0.05), whereas vessel proliferation was higher in AT(1A)KO hearts, which likely explains the later abundance of cells within the scar tissue. Insulin-like growth factor receptor-I was upregulated and its downstream signal protein kinase B (Akt) was significantly activated in infarcted AT(1A)KO hearts compared with WT hearts. Inactivation of Akt with wortmannin partially but significantly prevented the benefits observed in AT(1A)KO. Collectively, in AT(1A)KO hearts, Akt-mediated granulation tissue cell proliferation and preservation resulting from antiapoptosis likely contributed to an abundant cell population that altered the infarct scar structure, thereby reducing wall stress and attenuating LV dilatation and dysfunction at the chronic stage. In conclusion, altered structural dynamics of infarct scar and increasing myocardial fibrosis may be responsible for the deleterious effects of AT(1A) signaling following MI.


Assuntos
Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/patologia , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais , Androstadienos/farmacologia , Animais , Anti-Hipertensivos/farmacologia , Apoptose , Pressão Sanguínea/efeitos dos fármacos , Proliferação de Células , Fibrose , Tecido de Granulação/metabolismo , Tecido de Granulação/patologia , Hidralazina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Função Ventricular Esquerda , Remodelação Ventricular , Wortmanina
15.
Autophagy ; 2(3): 212-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16874110

RESUMO

Numerous cardiomyocytes were found to show autophagic vacuolar degeneration in the UM-X7.1 hamster model of human dilated cardiomyopathy, and autophagy-related proteins--i.e., ubiquitin, cathepsin D and Rab7--were upregulated in those hearts. Importantly, Evans blue-positive cardiomyocytes with leaky plasma membranes were also positive for cathepsin D, suggesting a link between autophagic degeneration and cell death. Treatment with granulocyte colony-stimulating factor (G-CSF) significantly improved survival, cardiac function and remodeling in these animals, and such beneficial effects were accompanied by a reduction in autophagy, an increase in cardiomyocyte size, and a reduction in myocardial fibrosis. G-CSF-induced changes in molecular signaling included activation of Akt and Stat3 (signal transducer and activator of transcription-3), a reduction in the level of myocardial tumor necrosis factor-alpha, and an increase in those of matrix metalloproteinases. In contrast, neither cardiomyocyte apoptosis nor regeneration of cardiomyocytes from bone marrow-derived cells was significant. It thus appears that autophagic death and autophagy-dependent degeneration are important contributors to loss of cardiomyocyte function in the cardiomyopathic hamster and that G-CSF exerts a beneficial effect, mainly via an anti-autophagic mechanism.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Insuficiência Cardíaca/patologia , Miócitos Cardíacos/patologia , Animais , Cardiomiopatia Dilatada/patologia , Cricetinae , Fator Estimulador de Colônias de Granulócitos/fisiologia , Insuficiência Cardíaca/etiologia , Humanos , Modelos Biológicos
16.
Cardiovasc Res ; 71(4): 684-94, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16828072

RESUMO

OBJECTIVES: Late treatment with erythropoietin (EPO), as well as the administration before the onset of or during the acute stage of myocardial infarction (MI), has recently been shown to mitigate post-MI heart failure. We investigated the mechanisms, including the downstream signaling pathways, for the beneficial effect of late treatment with EPO on chronic post-MI heart failure. METHODS AND RESULTS: EPO (1500 U/kg, twice a week) was administered to mice beginning 6 weeks after induction of large MI. The EPO treatment for 4 weeks diminished left ventricular dilatation and improved function. It significantly reduced inflammatory cell infiltration and fibrosis, and increased vascular density in noninfarcted areas. The elevated levels of the inflammatory cytokines interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha and transforming growth factor-beta1 seen in the failing hearts were returned nearly to control levels by EPO treatment. Oxidative damage in surviving cardiomyocytes was also significantly attenuated by EPO. Expression of EPO receptor was upregulated in failing hearts, and EPO treatment led to myocardial activation of signal transducer and activator of transcription-3 (Stat3), Stat5, and Akt. These in vivo effects of EPO were confirmed in vitro in experiments that showed the anti-inflammatory and anti-oxidant effects of EPO to be mediated via Stat and Akt activation. Finally, the beneficial effects of EPO were found to persist for 4 weeks after discontinuing treatment. CONCLUSIONS: It thus appears that Stat-mediated reduction of inflammation and cytokine production and Akt-mediated attenuation of oxidative stress accompany the beneficial effects of late treatment with EPO on chronic post-MI heart failure.


Assuntos
Citocinas/metabolismo , Eritropoetina/uso terapêutico , Insuficiência Cardíaca/imunologia , Miocárdio/imunologia , Animais , Western Blotting , Células Cultivadas , Ecocardiografia , Fibroblastos/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/patologia , Hematócrito , Peróxido de Hidrogênio/farmacologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Modelos Animais , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Oxirredução , Distribuição Aleatória , Receptores da Eritropoetina/análise , Receptores da Eritropoetina/metabolismo , Proteínas Recombinantes , Transdução de Sinais/efeitos dos fármacos , Tempo , Remodelação Ventricular/efeitos dos fármacos
17.
Circ J ; 70(6): 710-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16723792

RESUMO

BACKGROUND: The nucleus of the myocytes in human hypertrophic hearts is characterized by its bizarre shape and widespread clumping of chromatin. The functional significance has not been determined. METHODS AND RESULTS: Left ventricular (LV) endomyocardial biopsies obtained from patients with dilated cardiomyopathy (DCM, n=23), postmyocarditis (n=13), hypertrophic cardiomyopathy (HCM, n=21), apical hypertrophic cardiomyopathy (APH, n=11) and hypertensive heart disease (HHD, n=11), and from nonhypertrophic hearts (controls, n=14) were examined. Myocyte size and LV mass index were similar among the hypertrophic hearts, but the nuclear hypertrophy score (grade 0-3) was highest in hearts with systolic failure (DCM and postmyocarditis) and higher in those without it (HCM, APH, and HHD), compared with controls. So were biosynthetic activities such as DNA repair/synthesis, immunohistochemically assessed by proliferating cell nuclear antigen, transcription activity by spliceosome component of 35 kDa, and translation efficiency by 70 kDa S6 protein kinase. There were significant correlations between nuclear hypertrophy and each biosynthetic activity. Additionally, most of the proliferating cell nuclear antigen-positive nuclei co-expressed oxidative DNA damage markers. CONCLUSION: A link is suggested between structural alteration and molecular biological events in the nuclei of myocytes from human hypertrophic hearts; the nuclear hypertrophy reflects increased biosynthetic activities of DNA repair/synthesis, transcription, and translation efficiency.


Assuntos
Cardiomiopatia Dilatada/patologia , Cromatina/ultraestrutura , Miócitos Cardíacos/ultraestrutura , Idoso , Cardiomiopatia Dilatada/metabolismo , Cromatina/metabolismo , DNA/biossíntese , Reparo do DNA , Feminino , Humanos , Hipertensão/metabolismo , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Miocardite/metabolismo , Miocardite/patologia , Miócitos Cardíacos/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Biossíntese de Proteínas , Proteínas Quinases S6 Ribossômicas/metabolismo , Spliceossomos/metabolismo , Transcrição Gênica
18.
Circulation ; 113(4): 535-43, 2006 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-16449733

RESUMO

BACKGROUND: Doxorubicin is a highly effective antineoplastic drug, but its clinical use is limited by its adverse side effects on the heart. We investigated possible protective effects of erythropoietin against doxorubicin-induced cardiomyopathy. METHODS AND RESULTS: Cardiomyopathy was induced in mice by a single intraperitoneal injection of doxorubicin (15 mg/kg). In some cases, human recombinant erythropoietin (5000 U/kg) was started simultaneously. Two weeks later, left ventricular dilatation and dysfunction were apparent in mice given doxorubicin but were significantly attenuated by erythropoietin treatment. Erythropoietin also protected hearts against doxorubicin-induced cardiomyocyte atrophy and degeneration, myocardial fibrosis, inflammatory cell infiltration, and downregulation of expression of GATA-4 and 3 sarcomeric proteins, myosin heavy chain, troponin I, and desmin. Cyclooxygenase-2 expression was upregulated in doxorubicin-treated hearts, and that, too, was attenuated by erythropoietin. No doxorubicin-induced apoptotic effects were seen, nor were any changes seen in the expression of tumor necrosis factor-alpha or transforming growth factor-beta1. Antiatrophic and GATA-4 restoring effects of erythropoietin were demonstrated in the in vitro experiments with cultured cardiomyocytes exposed to doxorubicin, which indicated the direct cardioprotective effects of erythropoietin beyond erythropoiesis. Cardiac erythropoietin receptor expression was downregulated in doxorubicin-induced cardiomyopathy but was restored by erythropoietin. Among the downstream mediators of erythropoietin receptor signaling, activation of extracellular signal-regulated kinase was reduced by doxorubicin but restored by erythropoietin. By contrast, erythropoietin was ineffective when administered after cardiac dysfunction was established in the chronic stage. CONCLUSIONS: The present study indicates a protective effect of erythropoietin against doxorubicin-induced cardiomyopathy.


Assuntos
Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/prevenção & controle , Eritropoetina/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/prevenção & controle , Animais , Antibióticos Antineoplásicos , Cardiomiopatias/induzido quimicamente , Caspase 3 , Caspases/metabolismo , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Doxorrubicina , Contagem de Eritrócitos , Eritropoetina/sangue , Fator de Transcrição GATA4/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Receptores da Eritropoetina/metabolismo , Sarcômeros/metabolismo , Taxa de Sobrevida , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/prevenção & controle
19.
Am J Pathol ; 168(2): 386-97, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16436654

RESUMO

In UM-X7.1 hamster model of human dilated cardiomyopathy, heart failure progressively develops and causes 50% mortality by 30 weeks of age. Through ultrastructural analysis, we found that many cardiomyocytes of this model contain typical autophagic vacuoles including degraded mitochondria, glycogen granules, and myelin-like figures. In addition, ubiquitin, cathepsin D, and Rab7 were overexpressed as determined by immunoassays. Importantly, most cardiomyocytes with leaky plasma membranes were positive for cathepsin D, suggesting a direct link between autophagic degeneration and cell death. Meanwhile, cardiomyocyte apoptosis appeared insignificant. Granulocyte colony-stimulating factor (10 microg/kg/day), injected 5 days/week from 15 to 30 weeks of age, improved survival among 30-week-old hamsters (100% versus 53% in the untreated hamsters, P < 0.0001); ventricular function and remodeling, increased cardiomyocyte size, and reduced myocardial fibrosis followed by a dramatic reduction in the autophagic findings were also seen. Granulocyte colony-stimulating factor also down-regulated tumor necrosis factor-alpha and increased activities of Akt signal transducer and activator of transcription-3, and matrix metalloproteinases. However, there was no clear evidence of transdifferentiation from bone marrow cells into cardiomyocytes. In conclusion, autophagic death is important for cardiomyocyte loss in the cardiomyopathic hamster, and the beneficial effect of granulocyte colony-stimulating factor acts mainly via an anti-autophagic mechanism rather than anti-apo-ptosis or regeneration.


Assuntos
Apoptose , Autofagia , Cardiomiopatia Dilatada/prevenção & controle , Fibrose/prevenção & controle , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Miócitos Cardíacos/patologia , Animais , Cardiomiopatia Dilatada/metabolismo , Catepsina D/metabolismo , Cricetinae , Fibrose/metabolismo , Masculino , Mesocricetus , Mitocôndrias/patologia , Bainha de Mielina , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes , Fator de Transcrição STAT3/metabolismo , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina/metabolismo , Vacúolos , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
20.
Cardiovasc Res ; 69(2): 476-90, 2006 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16368087

RESUMO

OBJECTIVE: Whether bone marrow cells injected following acute myocardial infarction (MI) transdifferentiate into cardiomyocytes remains controversial, and how these cells affect repair-related cytokines is not known. METHODS: Autologous bone marrow-derived mononuclear cells (BM-MNCs) labeled with DiI, 1,1'-dioctadecyl-1 to 3,3,3',3'-tetramethylindocarbocyanine perchlorate, or saline were intravenously injected into rabbits 5 h following a 30-min ischemia and reperfusion protocol, and cardiac function and the general pathology of the infarcted heart were followed up 1 and 3 months post-MI. To search for regenerated myocardium, electron microscopy as well as confocal microscopy were performed in the infarcted myocardium 7 days post-MI. Expression levels of repair-related cytokines were evaluated by immunohistochemistry and Western blotting. RESULTS: Improvements in cardiac function and reductions in infarct size were observed in the BM-MNC group 1 month and 3 months post-MI. Using electron microscopy 7 days after infarction, clusters of very immature (fetal) and relatively mature cardiomyocytes undergoing differentiation were identified in the infarcted anterior LV wall in the BM-MNC group, though their numbers were small. These cells contained many small and dense DiI particles (a BM-MNC marker), indicating that cardiomyocytes had regenerated from the injected BM-MNCs. The expression of both transforming growth factor-beta, which stimulates collagen synthesis and matrix metalloproteinase-1, a collagenase, were both down-regulated 7 days and 1 month post-MI in the BM-MNC group. Stromal cell-derived factor-1, which is known to recruit BM-MNCs into target tissues, was overexpressed in the infarcted areas of BM-MNC hearts 7 days post-MI. CONCLUSIONS: Intravenous transplantation of BM-MNCs leads to the development of BM-MNC-derived myocyte-like cells and regulates the expression of repair-related cytokines that facilitate repair following myocardial infarction.


Assuntos
Células da Medula Óssea/citologia , Transplante de Medula Óssea , Citocinas/análise , Isquemia Miocárdica/cirurgia , Miócitos Cardíacos/patologia , Regeneração , Animais , Western Blotting/métodos , Diferenciação Celular , Quimiocina CXCL12 , Quimiocinas CXC/análise , Imuno-Histoquímica/métodos , Metaloproteinase 1 da Matriz/análise , Microscopia Confocal , Microscopia Eletrônica , Isquemia Miocárdica/imunologia , Isquemia Miocárdica/patologia , Miócitos Cardíacos/ultraestrutura , Coelhos , Fatores de Tempo , Fator de Crescimento Transformador beta/análise
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