RESUMO
BACKGROUND AND AIMS: Excessive alcohol consumption predisposes drinkers to develop alcoholic cardiomyopathy. Although cardiomyocyte loss is the hallmark of cardiomyopathy, the underlying mechanism remains elusive. This study examined the potential mechanism of alcohol-induced cardiomyocyte death in a mouse model of alcoholic cardiomyopathy. METHODS: We established the alcoholic cardiomyopathy mouse model using C57BL/6J mice and confirmed it via echocardiography and histological examination. The cardiac ceramide content and profile were analyzed with a triple-quadrupole mass spectrometer. The molecular mechanism underlying the accumulation of ceramide due to chronic alcohol consumption and ceramide-induced cardiomyocyte death were investigated by in vivo and in vitro models. Finally, we established a TLR4 mutation model to explore the function of TLR4 in CH3/HeJ mice. RESULTS: Cardiac lipotoxicity that followed alcohol exposure resulted mainly in C16:0-, C18:0-, and C24:1-ceramide aggregation. Genes encoding the sphingosine hydrolysis enzymes (SMPD1 and SMPD2) rather than de novo synthetic biomarkers were markedly upregulated. Exogenous ceramide mimics (C6-ceramide) werenderlying the accumulation of ceramide observed to cause H9C2 cardiomyocyte-like cell death, which was consistent with results under palmate acid (PA) treatment. As a ceramide precursor, PA induces intracellular ceramide generation through TLR4 signaling, which can be abolished by an inhibitor of ceramide synthesis. Furthermore, mechanistic investigations demonstrated that pharmacological or genetic inhibition of TLR4 attenuated PA-induced cell death and corresponding ceramide production. Moreover, global mutation of TLR4 in CH3/HeJ mice significantly reduced the accumulation of C24:0, C24:1, OH_C24:1, and total ceramide following alcohol challenge. CONCLUSIONS: Our findings demonstrate that ceramide accumulation plays a crucial role in alcoholic cardiomyopathy, effects that are partially mediated through the TLR4-dependent pathway.
Assuntos
Cardiomiopatia Alcoólica , Animais , Cardiomiopatia Alcoólica/metabolismo , Ceramidas/metabolismo , Modelos Animais de Doenças , Etanol/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Receptor 4 Toll-Like/genéticaRESUMO
INTRODUCTION: The purpose of this study was to evaluate subjects with high-risk alcohol cardiotoxicity and patients with alcoholic cardiomyopathy (ACM) via dynamic 11C-Acetate positron emission tomography (PET) imaging as a myocardial oxidative metabolic probe. METHODS AND RESULTS: We recruited 37 subjects with chronic alcohol consumption [18 with moderate consumption (MC), 19 with heavy consumption (HC)], 5 ACM patients, and 12 healthy controls to receive dynamic 11C-Acetate PET scans. PET imaging data were analyzed to calculate kinetic parameters (e.g., Kmono, K1 and k2) based on the mono-exponential and one-tissue compartmental models. Myocardial oxygen consumption (MVO2) and myocardial external efficiency (MEE) were then derived from these kinetic parameters. MVO2 was significantly lowered in the HC group and in ACM patients (0.121± 0.018 and 0.111 ± 0.017 mL·g-1·min-1, respectively) compared with those in healthy controls and MC subjects (0.144 ± 0.023 and 0.146 ± 0.027 mL·g-1·min-1, respectively; P < .01). MEE was significantly reduced in ACM patients (13.0% ± 4.3%) compared with those of healthy controls (22.4% ± 4.6%, P < .01), MC subjects (20.1% ± 4.5%, P < .05), and HC subjects (22.3% ± 4.5%, P < .001). CONCLUSION: Functional assessment via dynamic 11C-Acetate PET imaging may represent a clinically feasible probe for identifying cohorts with high-risk cardiotoxicity due to addictive alcohol consumption and ACM.
Assuntos
Cardiomiopatia Alcoólica , Acetatos/metabolismo , Cardiomiopatia Alcoólica/diagnóstico por imagem , Cardiomiopatia Alcoólica/metabolismo , Cardiotoxicidade , Humanos , Miocárdio/metabolismo , Estresse Oxidativo , Consumo de Oxigênio , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios XRESUMO
Chronic alcohol exposure can cause myocardial degenerative diseases, manifested as cardiac insufficiency, arrhythmia, etc. These are defined as alcoholic cardiomyopathy (ACM). Alcohol-mediated myocardial injury has previously been studied through metabolomics, and it has been proved to be involved in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway concerning unsaturated fatty acids biosynthesis and oxidative phosphorylation, which tentatively explored the mechanism of ACM induced by chronic drinking. To further study alcohol-induced myocardial injury, myocardial specimens from a previously successfully established mouse model of ACM were subjected to histological, echocardiographic, and proteomic analyses, and validated by real-time quantitative polymerase chain reaction (qPCR). Results of histopathology and echocardiography showed the hypertrophy of cardiomyocytes, the dilation of ventricles, and decreased cardiac function. Proteomic results, available via ProteomeXchange with identifier PXD032949, revealed 56 differentially expressed proteins (DEPs) were identified, which have the potential to be involved in the KEGG pathway related to fatty acid biosynthesis disorders, lipid metabolism disorders, oxidative stress, and, ultimately, in the development of dilated cardiomyopathy (DCM). The present study further elucidates the underlying effects of myocardial injury due to chronic alcohol intake, laying a foundation for further studies to clarify the potential mechanisms of ACM.
Assuntos
Cardiomiopatias , Cardiomiopatia Alcoólica , Animais , Cardiomiopatias/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Etanol/metabolismo , Etanol/toxicidade , Camundongos , Miocárdio/metabolismo , Projetos Piloto , ProteômicaRESUMO
Chronic excessive ethanol consumption is associated with a high incidence of mortality due to ethanol-induced dilated cardiomyopathy, known as alcoholic cardiomyopathy (ACM). Mechanistic studies have demonstrated that apoptosis is key to the pathogenesis of ACM, and endoplasmic reticulum (ER) stress-associated apoptosis contributes to various ethanol-related diseases. Astaxanthin (AST) is a natural carotenoid that exerts an anti-ER stress effect. Importantly, strong evidence has shown that AST induces beneficial effects in various cardiovascular diseases. The present study aimed to investigate whether AST induces beneficial effects on ACM by suppressing cardiac apoptosis mediated by ER stress. We showed that after 2 months of chronic excessive ethanol consumption, mice displayed obvious cardiac dysfunction and morphological changes associated with increased fibrosis, oxidative stress, ER stress and apoptosis. However, cardiac damage above was attenuated in response to AST treatment. The cardioprotective effect of AST against ethanol toxicity was also confirmed in both H9c2 cells and primary cardiomyocytes, indicating that AST-induced protection directly targets cardiomyocytes. Both in vivo and in vitro studies showed that AST inhibited all three ER stress signaling pathways activated by ethanol. Furthermore, administration of the ER stress inhibitor sodium 4-phenylbutyrate (4-PBA) strongly suppressed ethanol-induced cardiomyocyte damage. Interestingly, AST induced further anti-apoptotic effects once co-treated with 4-PBA, indicating that AST protects the heart from ACM partially by attenuating ER stress, but other mechanisms still exist. This study highlights that administration of AST ablated chronic excessive ethanol consumption-induced cardiomyopathy by suppressing cardiac ER stress and subsequent apoptosis.
Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cardiomiopatia Alcoólica/prevenção & controle , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Cardiomiopatia Alcoólica/etiologia , Cardiomiopatia Alcoólica/metabolismo , Cardiomiopatia Alcoólica/fisiopatologia , Linhagem Celular , Modelos Animais de Doenças , Etanol , Fibrose , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Transdução de Sinais , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Xantofilas/farmacologiaRESUMO
Chronic alcohol consumption leads to myocardial injury, ventricle dilation, and cardiac dysfunction, which is defined as alcoholic cardiomyopathy (ACM). To explore the induced myocardial injury and underlying mechanism of ACM, the Liber-DeCarli liquid diet was used to establish an animal model of ACM and histopathology, echocardiography, molecular biology, and metabolomics were employed. Hematoxylin-eosin and Masson's trichrome staining revealed disordered myocardial structure and local fibrosis in the ACM group. Echocardiography revealed thinning wall and dilation of the left ventricle and decreased cardiac function in the ACM group, with increased serum levels of brain natriuretic peptide (BNP) and expression of myocardial BNP mRNA measured through enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction (PCR), respectively. Through metabolomic analysis of myocardium specimens, 297 differentially expressed metabolites were identified which were involved in KEGG pathways related to the biosynthesis of unsaturated fatty acids, vitamin digestion and absorption, oxidative phosphorylation, pentose phosphate, and purine and pyrimidine metabolism. The present study demonstrated chronic alcohol consumption caused disordered cardiomyocyte structure, thinning and dilation of the left ventricle, and decreased cardiac function. Metabolomic analysis of myocardium specimens and KEGG enrichment analysis further demonstrated that several differentially expressed metabolites and pathways were involved in the ACM group, which suggests potential causes of myocardial injury due to chronic alcohol exposure and provides insight for further research elucidating the underlying mechanisms of ACM.
Assuntos
Alcoolismo/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Metabolômica , Miocárdio/metabolismo , Miocárdio/patologia , Alcoolismo/diagnóstico por imagem , Alcoolismo/fisiopatologia , Animais , Cardiomiopatia Alcoólica/diagnóstico por imagem , Cardiomiopatia Alcoólica/fisiopatologia , Análise Discriminante , Modelos Animais de Doenças , Eletrocardiografia , Testes de Função Cardíaca , Análise dos Mínimos Quadrados , Masculino , Metaboloma , Camundongos Endogâmicos C57BL , Análise de Componente Principal , Transdução de SinaisRESUMO
The molecular mechanisms underlying the cardioprotective effect of fabomotizole were studied using the translational rat model of alcoholic cardiomyopathy developed by us. It was shown that intraperitoneal administration of fabomotizole (15 mg/kg) for 28 days to animals with alcoholic cardiomyopathy contributes to normalization of the expression of mRNA of genes of regulatory proteins СаР(p=0.00001), ÐÑаÑ1 (p=0.021), and ÐÑаÑ2 (p=0.018) and receptors RyR2 (p=0.0031) and IP3R2 (p=0.006) in the myocardium of the myocardium of the left ventricle that is enhanced in control animals (p<0.05). These changes were accompanied by echocardiographically documented decrease in the degree of left ventricle remodeling and improvement of its inotropic function.
Assuntos
Cardiomiopatia Alcoólica , Animais , Cardiomiopatia Alcoólica/tratamento farmacológico , Cardiomiopatia Alcoólica/metabolismo , Ventrículos do Coração/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Ratos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismoRESUMO
Chronic alcohol consumption induces myocardial damage and a type of non-ischemic cardiomyopathy termed alcoholic cardiomyopathy, where mitochondrial ultrastructural damages and suppressed fusion activity promote cardiomyocyte apoptosis. The aim of the present study is to determine the role of mitochondrial fission proteins and/or other proteins that localise on cardiac mitochondria for apoptosis upon ethanol consumption. In vivo and in vitro chronic alcohol exposure increased mitochondrial Drp1 levels but knockdown of the same did not confer cardioprotection in H9c2 cells. These cells displayed downregulated expression of MFN2 and OPA1 for Bak-mediated cytochrome c release and apoptosis. Dysregulated PTEN/AKT cell survival signal in both ethanol treated and Drp1 knockdown cells augmented oxidative stress by promoting mitochondrial PTEN-L and MFN1 interaction. Inhibiting this interaction with VO-OHpic, a reversible PTEN inhibitor, prevented Bak insertion into the mitochondria and release of cytochrome c to cytoplasm. Thus, our study provides evidence that Drp1-mediated mitochondrial fission is dispensable for ethanol-induced cardiotoxicity and that stress signals induce mitochondrial PTEN-L accumulation for structural and functional dyshomeostasis. Our in vivo results also demonstrates the therapeutic potential of VO-OHpic for habitual alcoholics developing myocardial dysfunction.
Assuntos
Alcoolismo/genética , Apoptose/genética , Cardiomiopatia Alcoólica/genética , Dinaminas/genética , Etanol/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , PTEN Fosfo-Hidrolase/genética , Alcoolismo/metabolismo , Alcoolismo/patologia , Animais , Apoptose/efeitos dos fármacos , Cardiomiopatia Alcoólica/metabolismo , Cardiomiopatia Alcoólica/patologia , Linhagem Celular , Citocromos c/genética , Citocromos c/metabolismo , Modelos Animais de Doenças , Dinaminas/antagonistas & inibidores , Dinaminas/metabolismo , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Humanos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Compostos Organometálicos/farmacologia , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismoRESUMO
BACKGROUND: Chronic alcohol consumption initially leads to asymptomatic left ventricular dysfunction, but can result in myocardial impairment and heart failure if ongoing. This study sought to characterize myocardial tissues and oxidative metabolism in asymptomatic subjects with chronic alcohol consumption by quantitative cardiovascular magnetic resonance (CMR) and 11C-acetate positron emission tomography (PET)/computed tomography (CT). METHODS: Thirty-four male subjects (48.8 ± 9.1 years) with alcohol consumption > 28 g/day for > 10 years and 35 age-matched healthy male subjects (49.5 ± 9.7 years) underwent CMR and 11C-acetate PET/CT. Native and post T1 values and extracellular volume (ECV) from CMR and Kmono and K1 from PET imaging were measured. Quantitative measurements by CMR and PET imaging were compared between subjects with moderate to heavy alcohol consumption and healthy controls, and their correlations were also analyzed. RESULTS: Compared to healthy controls, subjects with alcohol consumption showed significantly shorter native T1 (1133 ± 65 ms vs. 1186 ± 31 ms, p < 0.001) and post T1 (477 ± 42 ms vs. 501 ± 38 ms, p = 0.008) values, greater ECV (28.2 ± 2.2% vs. 26.9 ± 1.3%, p = 0.003), marginally lower Kmono (57.6 ± 12.1 min- 1 × 10- 3 vs. 63.0 ± 11.7 min- 1 × 10- 3, p = 0.055), and similar K1 (0.82 ± 0.13 min- 1 vs. 0.83 ± 0.15 min- 1, p = 0.548) after adjusting for confounding factors. There were no significant differences in CMR measurements and K1 between subjects with heavy and moderate alcohol consumption (all p > 0.05). In contrast, subjects with heavy alcohol consumption showed significantly lower Kmono values compared to those with moderate alcohol consumption (52.9 ± 12.1 min- 1 × 10- 3 vs. 63.7 ± 9.2 min- 1 × 10- 3, p = 0.012). Strong and moderate correlations were found between K1 and ECV in healthy controls (r = 0.689, p = 0.013) and subjects with moderate alcohol consumption (r = 0.518, p = 0.048), respectively. CONCLUSION: Asymptomatic men with heavy alcohol consumption have detectable structural and metabolic changes in myocardium on CMR and 11C-acetate PET/CT. Compared with quantitative CMR, 11C-acetate PET/CT imaging may be more sensitive for detecting differences in myocardial damage among subjects with moderate to heavy alcohol consumption.
Assuntos
Acetatos/administração & dosagem , Consumo de Bebidas Alcoólicas/efeitos adversos , Carbono/administração & dosagem , Cardiomiopatia Alcoólica/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Miocárdio/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos/administração & dosagem , Adulto , Consumo de Bebidas Alcoólicas/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Estudos de Casos e Controles , Meios de Contraste/administração & dosagem , Gadolínio DTPA/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Oxirredução , Valor Preditivo dos Testes , Reprodutibilidade dos TestesRESUMO
BACKGROUND: The Lieber-DeCarli alcoholic liquid diet is a classical method for establishing animal models of alcoholic cardiomyopathy (ACM). No study has reported whether the AIN-93 diet, which is widely used as a standard diet for both long-term and short-term studies with laboratory animals, could be used to construct the ACM animal model. The present study intended to investigate whether the AIN-93 diet could be used to establish a mouse ACM model. METHODS: Twenty-four C57BL/6 male mice were randomly divided into 4 equally sized groups. In ethanol (EtOH)-fed groups, mice were fed a 4%-EtOH (w/v, 28% of total calories) alcoholic liquid diet of Lieber-DeCarli or the AIN-93 diet for chronic alcohol exposure for 180 days. In control-fed groups, mice were fed with non-EtOH liquid diets with the same calories as EtOH-fed groups. Morphological observations of the hearts and molecular investigation of the brain natriuretic peptide (BNP) were carried out by echocardiography, hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining, real-time quantitative polymerase chain reaction (qPCR), and enzyme-linked immunosorbent assay. RESULTS: Echocardiography showed that mice fed with either the 4%-EtOH Lieber-DeCarli diet or the 4%-EtOH AIN-93 diet had dilated ventricles and poor cardiac function. IHC staining of BNP, qPCR of BNP mRNA, and plasma concentration of BNP showed an up-regulated expression in mice fed with both the 4%-EtOH Lieber-DeCarli and 4%-EtOH AIN-93 diets. Less fatty liver was also observed in mice fed the AIN-93 alcoholic diet than those fed the Lieber-DeCarli alcoholic diet. CONCLUSIONS: The AIN-93 alcoholic liquid diet can be used to establish ACM animal models, as with the conventional Lieber-DeCarli alcoholic liquid diet.
Assuntos
Cardiomiopatia Alcoólica/etiologia , Dieta/efeitos adversos , Animais , Cardiomiopatia Alcoólica/diagnóstico por imagem , Cardiomiopatia Alcoólica/metabolismo , Depressores do Sistema Nervoso Central/toxicidade , Modelos Animais de Doenças , Ecocardiografia , Etanol/toxicidade , Fígado Gorduroso/patologia , Ventrículos do Coração/patologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Peptídeo Natriurético Encefálico/biossínteseRESUMO
BACKGROUND: (Pro)renin receptor (PRR), a novel member of the renin-angiotensin system, participates in various cardiovascular diseases. However, the role of PRR in alcoholic cardiomyopathy (ACM), which is caused by alcohol intake and manifests as myocardial damage and cardiac dysfunction, remains unclear. METHODS: PRR gene silencing was achieved by transfecting recombinant adenovirus expressing anti-PRR short hairpin RNA (PRR-shRNA). In vitro, primary rat cardiac fibroblasts (CFs) were cultured with the stimulation of alcohol (200 mM), with or without PRR-shRNA and PD98059. Immunofluorescence, RT-PCR, and Western blot were used to measure the protein and messenger (mRNA) expression of PRR, fibrotic factors, and members of related signaling pathways. In vivo, Wistar rats were fed a diet containing 9% (v/v) alcohol or a normal diet for 3 months, with or without PRR-shRNA. Sirius Red staining, immunohistochemical staining, and toluidine blue staining were used to evaluate myocardial fibrosis, oxidative stress, and inflammation response. RESULTS: Alcohol markedly increased PRR mRNA and protein expression in a time- and concentration-dependent manner in CFs. The increased expression of fibrotic factors induced by alcohol was prevented by PRR-shRNA and PD98059. Moreover, PRR-shRNA decreased the phosphorylation of extracellular regulated protein kinases (ERK) 1/2 in CFs. Furthermore, PRR-shRNA decreased cardiac fibrosis, reduced oxidative stress, and alleviated inflammation response in the myocardial tissue. CONCLUSIONS: Our results show that PRR-ERK1/2 signaling was involved in the development of ACM and that PRR could be a new target for the treatment of ACM.
Assuntos
Receptores de Superfície Celular/metabolismo , Animais , Western Blotting , Cardiomiopatia Alcoólica/metabolismo , Etanol/efeitos adversos , Imunofluorescência , Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Miocárdio/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Receptor de Pró-ReninaRESUMO
OBJECTIVES: To investigate the effects of atorvastatin on the ultrastructure and lipid metabolism of AC16 cardiomyocytes in response to alcohol-induced endoplasmic reticulum stress (ERS). DESIGN: The expression of the ERS-related factor GRP78 in the established ERS model was determined by western blotting. Alcohol-exposed cardiomyocytes were treated with various concentrations of atorvastatin, and GRP78 expression was measured. Cardiomyocyte ultrastructure was observed and SREBP-1c and triglyceride (TG) levels were evaluated. RESULTS: Exposure to ethanol for 0, 12, 24, and 48 h significantly affected GRP78 expression (0.19 ± 0.02, 0.27 ± 0.03, 0.39 ± 0.01, and 0.64 ± 0.02, respectively). GRP78 expression in the 1, 10, and 100 µmol L-1 atorvastatin-treated groups was 0.50 ± 0.04, 0.38 ± 0.03, and 0.24 ± 0.01, respectively, and significantly different from control group expression (0.19 ± 0.02); the expression in the alcohol group was 0.64 ± 0.02. Alcohol-treated AC16 cells had significantly larger and fewer mitochondria and disorganized cristae, often replaced by vacuoles. These aberrations decreased with increasing atorvastatin concentrations. SREBP-1c expression also differed significantly among all atorvastatin-treated and control groups (0.47 ± 0.04, 0.39 ± 0.03, and 0.31 ± 0.02; normal 0.25 ± 0.02; alcohol 0.56 ± 0.03). TG expression differed significantly between the 10 and 100 µmol L-1 groups (26.84 ± 1.63, 23.11 ± 2.05) and the alcohol group (36.35 ± 2.41). CONCLUSIONS: Atorvastatin inhibited the expression of the ERS-related factor GRP78 in response to alcohol exposure, improved cell morphology, and enhanced lipid metabolism in a cellular model of alcoholic cardiomyopathy.
Assuntos
Atorvastatina/farmacologia , Cardiomiopatia Alcoólica/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Etanol/toxicidade , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Cardiomiopatia Alcoólica/metabolismo , Cardiomiopatia Alcoólica/patologia , Linhagem Celular , Forma Celular/efeitos dos fármacos , Citoproteção , Relação Dose-Resposta a Droga , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/ultraestrutura , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Fatores de TempoRESUMO
The expression of Epac proteins (exchange protein directly activated by cAMP) and calmodulin (CaM) was assessed by the content of the corresponding mRNA in biopsy specimens of cardiac atrium, left ventricle, and thoracic aorta of rats with alcoholic cardiomyopathy. In the myocardium, overexpression of Ðpac1, ÐÑаÑ2, and СаРmRNA was found. The content of Epac2 mRNA in the left ventricle was elevated by 2.9 times (p=0.000001), in the left atrium by 3.2 times (p=0.00001), in the right atrium by 3 times (p=0.00001). In contrast to the myocardial tissue, the content of CaM mRNA in the thoracic aorta was not increased, but showed a tendency to decrease, when compared to the control values, while the level of Epac1 and Epac2 mRNA was increased. The assumption is made that regulatory proteins Epac and CaM can play a key role in arrhythmogenesis development under conditions of alcoholic cardiomyopathy.
Assuntos
Arritmias Cardíacas/genética , Calmodulina/genética , Cardiomiopatia Alcoólica/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Animais , Animais não Endogâmicos , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatologia , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Calmodulina/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Cardiomiopatia Alcoólica/fisiopatologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Átrios do Coração/metabolismo , Átrios do Coração/fisiopatologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transdução de SinaisRESUMO
Alcoholic cardiomyopathy (ACM) can develop after consumption of relatively large amounts of alcohol over time or from acute binge drinking. Of the many factors implicated in the etiology of ACM, chronic perturbation in protein balance has been strongly implicated. This review focused on recent contributions (since 2010) in the area of protein metabolism and cardiac function related to ACM. Data reviewed include that from in vitro and preclinical in vivo animal studies where alcohol or an oxidative metabolite was studied and outcome measures in either cardiomyocytes or whole heart pertaining to protein synthesis or degradation were reported. Additionally, studies on the contractile properties of cardiomyocytes were also included to link signal transduction with function. Methodological differences including the potential impact of sex, dosing, and duration/timing of alcohol administration are addressed. Acute and chronic alcohol consumption decreases cardiac protein synthesis and/or activation of proteins within the regulatory mammalian/mechanistic target of rapamycin complex pathway. Albeit limited, evidence suggests that myocardial protein degradation via the ubiquitin pathway is not altered, while autophagy may be enhanced in ACM. Alcohol impairs ex vivo cardiomyocyte contractility in relation to its metabolism and expression of proteins within the growth factor pathway. Dysregulation of protein metabolism, including the rate of protein synthesis and autophagy, may contribute to contractile deficits and is a hallmark feature of ACM meriting additional sex-inclusive, methodologically consistent studies.
Assuntos
Alcoolismo/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Contração Miocárdica/fisiologia , Miócitos Cardíacos/metabolismo , Biossíntese de Proteínas/fisiologia , Proteólise , Alcoolismo/fisiopatologia , Animais , Autofagia/fisiologia , Cardiomiopatia Alcoólica/fisiopatologia , HumanosRESUMO
Alcoholic cardiomyopathy in humans develops in response to chronic excessive alcohol consumption; however, good models of alcohol-induced cardiomyopathy in mice are lacking. Herein we describe mouse models of alcoholic cardiomyopathies induced by chronic and binge ethanol (EtOH) feeding and characterize detailed hemodynamic alterations, mitochondrial function, and redox signaling in these models. Mice were fed a liquid diet containing 5% EtOH for 10, 20, and 40 days (d) combined with single or multiple EtOH binges (5 g/kg body wt). Isocalorically pair-fed mice served as controls. Left ventricular (LV) function and morphology were assessed by invasive pressure-volume conductance approach and by echocardiography. Mitochondrial complex (I, II, IV) activities, 3-nitrotyrosine (3-NT) levels, gene expression of markers of oxidative stress (gp91phox, p47phox), mitochondrial biogenesis (PGC1α, peroxisome proliferator-activated receptor α), and fibrosis were examined. Cardiac steatosis and fibrosis were investigated by histological/immunohistochemical methods. Chronic and binge EtOH feeding (already in 10 days EtOH plus single binge group) was characterized by contractile dysfunction (decreased slope of end-systolic pressure-volume relationship and preload recruitable stroke work), impaired relaxation (decreased time constant of LV pressure decay and maximal slope of systolic pressure decrement), and vascular dysfunction (impaired arterial elastance and lower total peripheral resistance). This was accompanied by enhanced myocardial oxidative/nitrative stress (3-NT; gp91phox; p47phox; angiotensin II receptor, type 1a) and deterioration of mitochondrial complex I, II, IV activities and mitochondrial biogenesis, excessive cardiac steatosis, and higher mortality. Collectively, chronic plus binge EtOH feeding in mice leads to alcohol-induced cardiomyopathies (National Institute on Alcohol Abuse and Alcoholism models) characterized by increased myocardial oxidative/nitrative stress, impaired mitochondrial function and biogenesis, and enhanced cardiac steatosis.
Assuntos
Tecido Adiposo/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Etanol/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Disfunção Ventricular Esquerda/metabolismo , Tecido Adiposo/patologia , Tecido Adiposo/fisiopatologia , Animais , Cardiomiopatia Alcoólica/patologia , Cardiomiopatia Alcoólica/fisiopatologia , Modelos Animais de Doenças , Esquema de Medicação , Hemodinâmica/fisiologia , Camundongos , Mitocôndrias/metabolismo , Biogênese de Organelas , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
Cardiac dysfunction caused by excessive alcohol consumption is a specific disease, alcoholic cardiomyopathy (ACM). High-dose alcohol has been found to induce oxidation stress and apoptosis in cardiomyocytes, but the signaling link between alcohol-induced oxidation stress and apoptosis in cardiomyocytes remains to be elucidated. To address the issue, we exposed primary cardiomyocytes from neonatal mouse hearts to high doses of alcohol (50mM, 100mM, and 200 mM). We found that alcohol induced dose-dependent phosphorylation of p66shc, and reactive oxygen species (ROS) production increased in parallel with phosphorylation levels of p66shc. Exposure to alcohol also led to loss of mitochondrial membrane potential and cytochrome c release. Depletion of p66Shc and inhibition of protein kinase C-ß (PKC-ß) successfully reversed all the effects and suppressed alcohol-induced apoptosis in cardiomyocytes. Collectively, our study provides a molecular basis for signaling transduction of alcohol-induced oxidation stress and apoptosis of cardiomyocytes, which may facilitate the prevention and treatment of ACM.
Assuntos
Apoptose/efeitos dos fármacos , Etanol/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo , Proteína Quinase C beta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Animais , Cardiomiopatia Alcoólica/enzimologia , Cardiomiopatia Alcoólica/metabolismo , Citocromos c/metabolismo , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Maleimidas/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Fosforilação , Proteína Quinase C beta/antagonistas & inibidores , RNA Interferente Pequeno/genética , Proteínas Adaptadoras da Sinalização Shc/genética , Transdução de Sinais , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de SrcRESUMO
The objective of the present study was to study the morphological criteria for toxic cardiopathy with the use of histological and immunohistochemical methods. The results of immunohistochemical studies of the sinoatrial node---???---(SAN) and the working myocardium in the patients presenting with alcoholic cardiomyopathy (ACMP) are presented. It was shown that vimentin expression in the SAN structures and the contractile myocardium is slightly increased whereas the expression of sarcomeric actin is decreased and that of fibrinogen is increased too. The authors put forward an assumption about the role of lesions in the membrane apparatus of the pacemaker cells in the development of arrhythmia characteristic of tanatogenesis associated with alcoholic cardiomyopathy.
Assuntos
Cardiomiopatia Alcoólica/patologia , Etanol/análise , Medicina Legal/métodos , Sistema de Condução Cardíaco/química , Imuno-Histoquímica/métodos , Adulto , Cardiomiopatia Alcoólica/metabolismo , Causas de Morte , Feminino , Sistema de Condução Cardíaco/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
On the model of alcohol cardiomyopathy studied the effect of chronic ethanol consumption and the insulation stress on the reactivity of isolated rat aorta and the expression of the endogenous vasoconstrictor receptors in the aorta. Pushing alcoholization outbred rats was carried out for 24-28 weeks, using as the sole source of liquid 10% ethanol solution. In assessing the results of the study took into account the age of the animals. It is found that the reactivity of isolated aortic rings dissected from the body of old (40-45 weeks) nonstressed rats in response to endothelin-1 (ET1), noradrenaline (NA), arginine vasopressin (AVP) or angiotensin II (ATII) is not different from such reactivity for young animals. However, with the increase in life expectancy increases the sensitivity of vessels to vasoconstrictor action of serotonin (5HT). Prolonged stress insulation and the consumption of high doses of ethanol the stress lead to increased ET1- and NA-induced contraction of the aortic rings and a significant decrease in contractile response of the aorta to the impact ATII and AVP. Stress and alco- hol in combination with stress causing reduction mRNA ETA-R, AT1A-R. and V1A-R and increased mRNA α1-AR in rat aorta. It is found that in the vessels of stressed and alcoholized animals reduced level of expression of cytosolic glucocorticoid receptors (GR), which is a transcription factor for genes ETA-R, AT1A-R V1A-R. It is propoused that the development of vascular hyporesponsiveness of stressed and alcoholized rats to action ATII and AVP is the result of reducing the expression of their receptors on the GR-dependent mechanism. It is shown that under the influence of ethanol vessels become hyporeactivity selectively with respect to the action of 5HT. The mechanism of this process is unclear. Importantly, the changes in the contractile properties vessels recovered from the rat at 1 month after the abolition of the reception of ethanol (step abstinence) were similar to changes found at the alcohohzed animals. Thus, the importance of breaking the neuroendocrine regulation of vascular tone during long-term consumption of ethanol has a stressor components. Furthermore, in this experimental model we not received data in favor ethanol direct impact on the development of hypertension.
Assuntos
Aorta/metabolismo , Cardiomiopatia Alcoólica/metabolismo , Regulação da Expressão Gênica , Receptor Tipo 1 de Angiotensina/biossíntese , Receptores de Vasopressinas/biossíntese , Estresse Fisiológico , Angiotensina II/biossíntese , Animais , Aorta/patologia , Arginina Vasopressina/biossíntese , Cardiomiopatia Alcoólica/patologia , Endotelina-1/biossíntese , Masculino , RatosRESUMO
Immunohistochemical (IHC) methods and polymerase chain reaction (PCR) were employed to study the cases of death from alcoholic cardiomyopathy (ACMP) among the patients presenting with interstitial myocarditis who did not have this condition in their medical histories. IHC studies revealed the expression of anti-parvovirus B19 antibodies in cardiomyocytes (CMC) and inflammatory infiltrate cells of 40% of the patients. These antibodies were expressed in vascular smooth cells and inflammatory infiltrate cells from 70% of the patients. Cardiomyocytes expressed VP1 antigen of enteroviruses. The expression of V 19 parvovirus antigen occurred in 67% of the patients who died from alcoholic cardiomyopathy. The parvovirus V 19 was expressed in a smaller number of cardiomyocytes than enterovirus V1. PCR revealed the presence of parvovirus in 35% of the patients with ACMP compared with 15% of the control subjects. Type 6 herpes simplex virus was identified with the help of PCR in 30% of the patients with alcoholic cardiomyopathy, butonly in 8% of the patients in the control group. It is concluded that the use of immunohistochemical methods and polymerase chain reaction extends the diagnostic potential of histiological studies carried out to elucidate etiology of myocarditis in the patients who died from alcoholic cardiomyopathy.
Assuntos
Antígenos Virais/genética , Cardiomiopatia Alcoólica/complicações , DNA Viral/genética , Regulação Viral da Expressão Gênica , Miocardite/etiologia , Miocárdio/metabolismo , Parvovirus B19 Humano/genética , Antígenos Virais/biossíntese , Cardiomiopatia Alcoólica/diagnóstico , Cardiomiopatia Alcoólica/metabolismo , Humanos , Imuno-Histoquímica , Miocardite/diagnóstico , Miocardite/metabolismo , Miocárdio/patologia , Reação em Cadeia da PolimeraseRESUMO
BACKGROUND: The induction of mitochondrial quality control (MQC) mechanisms is essential for the re-establishment of mitochondrial homeostasis and cellular bioenergetics during periods of stress. Although MQC activation has cardioprotective effects in various cardiovascular diseases, its precise role and regulatory mechanisms in alcoholic cardiomyopathy (ACM) remain incompletely understood. METHODS: We explored whether two mitochondria-related proteins, phosphoglycerate mutase 5 (Pgam5) and prohibitin 2 (Phb2), influence MQC in male mice during ACM. RESULTS: Myocardial Pgam5 expression was upregulated in a male mouse model of ACM. Notably, following ACM induction, heart dysfunction was markedly reversed in male cardiomyocyte-specific Pgam5 knockout (Pgam5cKO) mice. Meanwhile, in alcohol-treated male mouse-derived neonatal cardiomyocytes, Pgam5 depletion preserved cell survival and restored mitochondrial dynamics, mitophagy, mitochondrial biogenesis and the mitochondrial unfolded protein response (mtUPR). We further found that in alcohol-treated cardiomyocyte, Pgam5 binds Phb2 and induces its dephosphorylation at Ser91. Alternative transduction of phospho-mimetic (Phb2S91D) and phospho-defective (Phb2S9A) Phb2 mutants attenuated and enhanced, respectively, alcohol-related mitochondrial dysfunction in cardiomyocytes. Moreover, transgenic male mice expressing Phb2S91D were resistant to alcohol-induced heart dysfunction. CONCLUSIONS: We conclude that ACM-induced Pgam5 upregulation results in Pgam5-dependent Phb2S91 dephosphorylation, leading to MQC destabilisation and mitochondrial dysfunction in heart. Therefore, modulating the Pgam5/Phb2 interaction could potentially offer a novel therapeutic strategy for ACM in male mice. HIGHLIGHTS: Pgam5 knockout attenuates alcohol-induced cardiac histopathology and heart dysfunction in male mice. Pgam5 KO reduces alcohol-induced myocardial inflammation, lipid peroxidation and metabolic dysfunction in male mice. Pgam5 depletion protects mitochondrial function in alcohol-exposed male mouse cardiomyocytes. Pgam5 depletion normalises MQC in ACM. EtOH impairs MQC through inducing Phb2 dephosphorylation at Ser91. Pgam5 interacts with Phb2 and induces Phb2 dephosphorylation. Transgenic mice expressing a Ser91 phospho-mimetic Phb2 mutant are resistant to ACM.
Assuntos
Cardiomiopatia Alcoólica , Proibitinas , Proteínas Repressoras , Animais , Masculino , Camundongos , Cardiomiopatia Alcoólica/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Modelos Animais de Doenças , Fosforilação , Mitocôndrias/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Fosfoproteínas Fosfatases/genética , Miócitos Cardíacos/metabolismo , Camundongos KnockoutRESUMO
We present in this review contemporary views on pathogenesis of alcoholic cardiomyopathy. Alcoholic cardiomyopathy has features of dilated cardiomyopathy and is manifested by increased volume and hypertrophy of the left ventricle, diminished contractile capacity, and when decompensated - by lowering of cardiac output. Pathogenic action of alcohol on cardiomyocytes leads to activation of apoptosis, dysfunction of intracellular organelles, alterations of the system of myofilaments, disorder of intracellular homeostasis of calcium. Ethanol metabolite acetaldehyde, products of minor pathway of catecholamine metabolism, changes in the endocannabinoid system, and activation of processes of lipid peroxidation all contribute to the myocardial damage. The basis of pathogenesis of alcoholic cardiomyopathy constitute proliferation of microperoxisomes and disbalance between acyloxidase and catalase leading to accumulation of hydrogen peroxide inside myocytes.