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1.
Nat Commun ; 11(1): 4666, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938943

RESUMO

Intercalated discs (ICD), specific cell-to-cell contacts that connect adjacent cardiomyocytes, ensure mechanical and electrochemical coupling during contraction of the heart. Mutations in genes encoding ICD components are linked to cardiovascular diseases. Here, we show that loss of Xinß, a newly-identified component of ICDs, results in cardiomyocyte proliferation defects and cardiomyopathy. We uncovered a role for Xinß in signaling via the Hippo-YAP pathway by recruiting NF2 to the ICD to modulate cardiac function. In Xinß mutant hearts levels of phosphorylated NF2 are substantially reduced, suggesting an impairment of Hippo-YAP signaling. Cardiac-specific overexpression of YAP rescues cardiac defects in Xinß knock-out mice-indicating a functional and genetic interaction between Xinß and YAP. Our study reveals a molecular mechanism by which cardiac-expressed intercalated disc protein Xinß modulates Hippo-YAP signaling to control heart development and cardiac function in a tissue specific manner. Consequently, this pathway may represent a therapeutic target for the treatment of cardiovascular diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas com Domínio LIM/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Cardiomiopatia Dilatada/genética , Comunicação Celular , Proteínas de Ciclo Celular/genética , Proliferação de Células , Proteínas do Citoesqueleto/genética , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ventrículos do Coração/crescimento & desenvolvimento , Proteínas com Domínio LIM/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Miócitos Cardíacos/citologia , Miócitos Cardíacos/patologia , Neurofibromina 2/genética , Neurofibromina 2/metabolismo , Proteínas Nucleares/genética , Transdução de Sinais
2.
Int J Nanomedicine ; 15: 4859-4876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764923

RESUMO

Introduction: CoenzymeQ10 (CoQ10) is a well-known antioxidant and anti-inflammatory agent with cardioprotective properties. However, clinical trials based on its oral administration have failed to provide significant effect on cardiac functionality. The main limitation of CoQ10 is based on its very low oral bioavailability and instability that limit dramatically its effects as a cardioprotective agent. Herein, we loaded CoQ10 in high bioavailable nano-emulsions (NEs) coated with chitosan or chitosan and hyaluronic acid in order to improve its performance. Methods: We tested cardioprotective and hepatoprotective effects of CoQ10-loaded nano-carriers against Doxorubicin and Trastuzumab toxicities in cardiomyocytes and liver cells through analysis of cell viability, lipid peroxidation, expression of leukotrienes, p65/NF-kB and pro-inflammatory cytokines involved in anticancer-induced cardio and hepatotoxicity. Results: Nano-carriers showed high stability and loading ability and increased cell viability both in hepatocytes and cardiomyocytes during anticancer treatments. We observed that these effects are mediated by the inhibition of lipid peroxidation and reduction of the inflammation. CoQ10-loaded nano-emulsions showed also strong anti-inflammatory effects reducing leukotriene B4 and p65/NF-κB expression and Interleukin 1ß and 6 production during anticancer treatments. Discussion: Anthracyclines and Human epidermal growth factor receptor (HER2) inhibitors have shown significant anticancer effects in clinical practice but their use is characterized by cardiotoxicity and hepatotoxicity. Nano-carriers loaded with CoQ10 showed cardio and hepatoprotective properties mediated by reduction of oxidative damages and pro-inflammatory mediators. These results set the stage for preclinical studies of cardio and hepatoprotection in HER2+ breast cancer-bearing mice treated with Doxorubicin and Trastuzumab.


Assuntos
Antraciclinas/efeitos adversos , Fígado/citologia , Miócitos Cardíacos/efeitos dos fármacos , Nanoestruturas/química , Trastuzumab/efeitos adversos , Ubiquinona/análogos & derivados , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cápsulas , Cardiotônicos/química , Cardiotônicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Feminino , Hepatócitos/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Ubiquinona/química , Ubiquinona/farmacologia
3.
Nat Commun ; 11(1): 3881, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753572

RESUMO

Cells typically respond to chemical or physical perturbations via complex signaling cascades which can simultaneously affect multiple physiological parameters, such as membrane voltage, calcium, pH, and redox potential. Protein-based fluorescent sensors can report many of these parameters, but spectral overlap prevents more than ~4 modalities from being recorded in parallel. Here we introduce the technique, MOSAIC, Multiplexed Optical Sensors in Arrayed Islands of Cells, where patterning of fluorescent sensor-encoding lentiviral vectors with a microarray printer enables parallel recording of multiple modalities. We demonstrate simultaneous recordings from 20 sensors in parallel in human embryonic kidney (HEK293) cells and in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and we describe responses to metabolic and pharmacological perturbations. Together, these results show that MOSAIC can provide rich multi-modal data on complex physiological responses in multiple cell types.


Assuntos
Técnicas Biossensoriais/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Microscopia de Fluorescência/métodos , Miócitos Cardíacos/metabolismo , Imagem Óptica/métodos , Potenciais de Ação/efeitos dos fármacos , Antagonistas Adrenérgicos beta/farmacologia , Técnicas Biossensoriais/instrumentação , Cálcio/química , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Peróxido de Hidrogênio/farmacologia , Concentração de Íons de Hidrogênio , Células-Tronco Pluripotentes Induzidas/citologia , Mitocôndrias/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Imagem Óptica/instrumentação , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Propanolaminas/farmacologia
4.
Nat Commun ; 11(1): 3955, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769998

RESUMO

Cellular therapy to treat heart failure is an ongoing focus of intense research, but progress toward structural and functional recovery remains modest. Engineered augmentation of established cellular effectors overcomes impediments to enhance reparative activity. Such 'next generation' implementation includes delivery of combinatorial cell populations exerting synergistic effects. Concurrent isolation and expansion of three distinct cardiac-derived interstitial cell types from human heart tissue, previously reported by our group, prompted design of a 3D structure that maximizes cellular interaction, allows for defined cell ratios, controls size, enables injectability, and minimizes cell loss. Herein, mesenchymal stem cells (MSCs), endothelial progenitor cells (EPCs) and c-Kit+ cardiac interstitial cells (cCICs) when cultured together spontaneously form scaffold-free 3D microenvironments termed CardioClusters. scRNA-Seq profiling reveals CardioCluster expression of stem cell-relevant factors, adhesion/extracellular-matrix molecules, and cytokines, while maintaining a more native transcriptome similar to endogenous cardiac cells. CardioCluster intramyocardial delivery improves cell retention and capillary density with preservation of cardiomyocyte size and long-term cardiac function in a murine infarction model followed 20 weeks. CardioCluster utilization in this preclinical setting establish fundamental insights, laying the framework for optimization in cell-based therapeutics intended to mitigate cardiomyopathic damage.


Assuntos
Microambiente Celular , Miocárdio/patologia , Cicatrização , Animais , Animais Recém-Nascidos , Capilares/patologia , Agregação Celular , Morte Celular , Linhagem da Célula , Tamanho Celular , Citoproteção , Células Progenitoras Endoteliais/citologia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Recém-Nascido , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos NOD , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/citologia , Estresse Oxidativo , Comunicação Parácrina , Ratos Sprague-Dawley , Transcrição Genética
5.
PLoS Comput Biol ; 16(8): e1008109, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797034

RESUMO

In the last decade, there has been tremendous progress in identifying genetic anomalies linked to clinical disease. New experimental platforms have connected genetic variants to mechanisms underlying disruption of cellular and organ behavior and the emergence of proarrhythmic cardiac phenotypes. The development of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) signifies an important advance in the study of genetic disease in a patient-specific context. However, considerable limitations of iPSC-CM technologies have not been addressed: 1) phenotypic variability in apparently identical genotype perturbations, 2) low-throughput electrophysiological measurements, and 3) an immature phenotype which may impact translation to adult cardiac response. We have developed a computational approach intended to address these problems. We applied our recent iPSC-CM computational model to predict the proarrhythmic risk of 40 KCNQ1 genetic variants. An IKs computational model was fit to experimental data for each mutation, and the impact of each mutation was simulated in a population of iPSC-CM models. Using a test set of 15 KCNQ1 mutations with known clinical long QT phenotypes, we developed a method to stratify the effects of KCNQ1 mutations based on proarrhythmic markers. We utilized this method to predict the severity of the remaining 25 KCNQ1 mutations with unknown clinical significance. Tremendous phenotypic variability was observed in the iPSC-CM model population following mutant perturbations. A key novelty is our reporting of the impact of individual KCNQ1 mutant models on adult ventricular cardiomyocyte electrophysiology, allowing for prediction of mutant impact across the continuum of aging. This serves as a first step toward translating predicted response in the iPSC-CM model to predicted response of the adult ventricular myocyte given the same genetic mutation. As a whole, this study presents a new computational framework that serves as a high throughput method to evaluate risk of genetic mutations based-on proarrhythmic behavior in phenotypically variable populations.


Assuntos
Canal de Potássio KCNQ1/genética , Modelos Cardiovasculares , Mutação/genética , Miócitos Cardíacos , Arritmias Cardíacas/genética , Biologia Computacional , Predisposição Genética para Doença/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/classificação , Miócitos Cardíacos/citologia
6.
PLoS One ; 15(8): e0237591, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833978

RESUMO

The slow cardiac delayed rectifier current (IKs) is formed by KCNQ1 and KCNE1 subunits and is one of the major repolarizing currents in the heart. Decrease of IKs currents either due to inherited mutations or pathological remodeling is associated with increased risk for cardiac arrhythmias and sudden death. Ca2+-dependent PKC isoforms (cPKC) are chronically activated in heart disease and diabetes. Recently, we found that sustained stimulation of the calcium-dependent PKCßII isoform leads to decrease in KCNQ1 subunit membrane localization and KCNQ1/KCNE1 channel activity, although the role of KCNE1 in this regulation was not explored. Here, we show that the auxiliary KCNE1 subunit expression is necessary for channel internalization. A mutation in a KCNE1 phosphorylation site (KCNE1(S102A)) abolished channel internalization in both heterologous expression systems and cardiomyocytes. Altogether, our results suggest that KCNE1(S102) phosphorylation by PKCßII leads to KCNQ1/KCNE1 channel internalization in response to sustained PKC stimulus, while leaving KCNQ1 homomeric channels in the membrane. This preferential internalization is expected to have strong impact on cardiac repolarization. Our results suggest that KCNE1(S102) is an important anti-arrhythmic drug target to prevent IKs pathological remodeling leading to cardiac arrhythmias.


Assuntos
Cálcio/metabolismo , Canal de Potássio KCNQ1/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Proteína Quinase C/metabolismo , Animais , Feminino , Células HEK293 , Humanos , Canal de Potássio KCNQ1/genética , Mutação , Miócitos Cardíacos/citologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Proteína Quinase C/genética , Ratos
7.
PLoS One ; 15(7): e0235922, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32673370

RESUMO

We have previously established that epigenetic regulator RING1 and YY1 binding protein (RYBP) is required for the contractility of embryonic stem (ES) cell derived cardiomyocytes (CMCs), suggesting its essential role in contractility. In order to investigate the underlying molecular events of this phenotype, we compared the transcriptomic profile of the wild type and Rybp null mutant ES cells and CMCs differentiated from these cell lines. We identified genes related to ion homeostasis, cell adhesion and sarcomeric organization affected in the Rybp null mutant CMCs, by using hierarchical gene clustering and Gene Ontology analysis. We have also demonstrated that the amount of RYBP is drastically reduced in the terminally differentiated wild type CMCs whilst it is broadly expressed in the early phase of differentiation when progenitors form. We also describe that RYBP is important for the proper expression of key cardiac transcription factors including Mesp1, Shh and Mef2c. These findings identify Rybp as a gene important for both early cardiac gene transcription and consequent sarcomere formation necessary for contractility. Since impairment of sarcomeric function and contractility plays a central role in reduced cardiac pump function leading to heart failures in human, current results might be relevant to the pathophysiology of cardiomyopathies.


Assuntos
Proteínas Repressoras/genética , Sarcômeros/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , RNA Mensageiro/metabolismo , Proteínas Repressoras/deficiência
8.
PLoS One ; 15(7): e0236547, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716920

RESUMO

Occlusal disharmony leads to morphological changes in the hippocampus and osteopenia of the lumbar vertebra and long bones in mice, and causes stress. Various types of stress are associated with increased incidence of cardiovascular disease, but the relationship between occlusal disharmony and cardiovascular disease remain poorly understood. Therefore, in this work, we examined the effects of occlusal disharmony on cardiac homeostasis in bite-opening (BO) mice, in which a 0.7 mm space was introduced by cementing a suitable applicance onto the mandibular incisior. We first examined the effects of BO on the level of serum corticosterone, a key biomarker for stress, and on heart rate variability at 14 days after BO treatment, compared with baseline. BO treatment increased serum corticosterone levels by approximately 3.6-fold and the low frequency/high frequency ratio, an index of sympathetic nervous activity, was significantly increased by approximately 4-fold by the BO treatment. We then examined the effects of BO treatment on cardiac homeostasis in mice treated or not treated with the non-selective ß-blocker propranolol for 2 weeks. Cardiac function was significantly decreased in the BO group compared to the control group, but propranolol ameliorated the dysfunction. Cardiac fibrosis, myocyte apoptosis and myocyte oxidative DNA damage were significantly increased in the BO group, but propranolol blocked these changes. The BO-induced cardiac dysfunction was associated with increased phospholamban phosphorylation at threonine-17 and serine-16, as well as inhibition of Akt/mTOR signaling and autophagic flux. These data suggest that occlusal disharmony might affect cardiac homeostasis via alteration of the autonomic nervous system.


Assuntos
Apoptose , Dano ao DNA , Miocárdio/patologia , Estresse Fisiológico , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Corticosterona/sangue , Eletrocardiografia , Fibrose , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
9.
PLoS One ; 15(6): e0234087, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511282

RESUMO

BACKGROUND: Ventricular septal perforation and left ventricular aneurysm are examples of potentially fatal complications of myocardial infarction. While various artificial materials are used in the repair of these issues, the possibility of associated infection and calcification is non-negligible. Cell-seeded biodegradable tissue-engineered patches may be a potential solution. This study evaluated the feasibility of a new left ventricular patch rat model to study neotissue formation in biodegradable cardiac patches. METHODS: Human induced pluripotent stem cell-derived cardiac progenitor cells (hiPS-CPCs) were cultured onto biodegradable patches composed of polyglycolic acid and a 50:50 poly (l-lactide-co-ε-caprolactone) copolymer for one week. After culturing, patches were implanted into left ventricular walls of male athymic rats. Unseeded controls were also used (n = 10/group). Heart conditions were followed by echocardiography and patches were subsequently explanted at 1, 2, 6, and 9 months post-implantation for histological evaluation. RESULT: Throughout the study, no patches ruptured demonstrating the ability to withstand the high pressure left ventricular system. One month after transplantation, the seeded patch did not stain positive for human nuclei. However, many new blood vessels formed within patches with significantly greater vessels in the seeded group at the 6 month time point. Echocardiography showed no significant difference in left ventricular contraction rate between the two groups. Calcification was found inside patches after 6 months, but there was no significant difference between groups. CONCLUSION: We have developed a surgical method to implant a bioabsorbable scaffold into the left ventricular environment of rats with a high survival rate. Seeded hiPS-CPCs did not differentiate into cardiomyocytes, but the greater number of new blood vessels in seeded patches suggests the presence of cell seeding early in the remodeling process might provide a prolonged effect on neotissue formation. This experiment will contribute to the development of a treatment model for left ventricular failure using iPS cells in the future.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Engenharia Tecidual , Implantes Absorvíveis , Animais , Modelos Animais de Doenças , Ecocardiografia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/transplante , Poliésteres/química , Ácido Poliglicólico/química , Ratos , Ratos Nus , Tecidos Suporte/química , Troponina T/metabolismo , Função Ventricular
10.
Nature ; 582(7811): 271-276, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32499640

RESUMO

A major factor in the progression to heart failure in humans is the inability of the adult heart to repair itself after injury. We recently demonstrated that the early postnatal mammalian heart is capable of regeneration following injury through proliferation of preexisting cardiomyocytes1,2 and that Meis1, a three amino acid loop extension (TALE) family homeodomain transcription factor, translocates to cardiomyocyte nuclei shortly after birth and mediates postnatal cell cycle arrest3. Here we report that Hoxb13 acts as a cofactor of Meis1 in postnatal cardiomyocytes. Cardiomyocyte-specific deletion of Hoxb13 can extend the postnatal window of cardiomyocyte proliferation and reactivate the cardiomyocyte cell cycle in the adult heart. Moreover, adult Meis1-Hoxb13 double-knockout hearts display widespread cardiomyocyte mitosis, sarcomere disassembly and improved left ventricular systolic function following myocardial infarction, as demonstrated by echocardiography and magnetic resonance imaging. Chromatin immunoprecipitation with sequencing demonstrates that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and cell cycle. Finally, we show that the calcium-activated protein phosphatase calcineurin dephosphorylates Hoxb13 at serine-204, resulting in its nuclear localization and cell cycle arrest. These results demonstrate that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and proliferation and provide mechanistic insights into the link between hyperplastic and hypertrophic growth of cardiomyocytes.


Assuntos
Calcineurina/metabolismo , Proliferação de Células , Proteínas de Homeodomínio/metabolismo , Proteína Meis1/metabolismo , Miócitos Cardíacos/citologia , Animais , Animais Recém-Nascidos , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Coração/fisiologia , Proteínas de Homeodomínio/genética , Masculino , Camundongos , Miocárdio/citologia , Ligação Proteica , Regeneração
11.
Nihon Yakurigaku Zasshi ; 155(3): 171-174, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32378638

RESUMO

Cardiac safety assessments play a key role in drug development. New non-clinical cardiac safety risk assessments, such as the use of iPSC-derived cardiomyocytes, have been validated by several consortiums both in Japan and abroad. The emerging multidisciplinary field of cardio-oncology has been recognized more important. The success of new cancer therapies has improved life expectancy of cancer patients, hence more attention has been paid to cardiotoxicities associated with existing and new anti-cancer therapies, such as cardiomyocyte injury and heart failure, vascular injury and hypertension or thrombosis, which accelerated coronary artery disease. In addition to the well-studied proarrhythmia risk, some cardiotoxicities, such as contractility impairment, are expected to be evaluated by iPSC-derived cardiomyocytes. Here we developed a novel imaging-based in vitro contractility assay using iPSC-derived cardiomyocytes. In the review, we would like to discuss the current status and future perspectives in the assessment of cardiac contractile function by anti-cancer agents.


Assuntos
Cardiologia/tendências , Células-Tronco Pluripotentes Induzidas/citologia , Oncologia/tendências , Miócitos Cardíacos/citologia , Cardiotoxicidade , Humanos , Pesquisa Interdisciplinar , Neoplasias/tratamento farmacológico
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(3): 205-211, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32389167

RESUMO

Objective To investigate the effects of phosphate and tension homology deleted on chromsome ten (PTEN) knockout on rat heart function and pyroptosis of cardiomyocytes mediated by NLR family pyrin domain containing 3 (NLRP3). Methods Rat models of myocardial ischemia/reperfusion (I/R) injury were established. The rats were divided into sham operation group (wild-type healthy rats), wild-type I/R group (wild-type healthy rats treated with myocardial I/R), and I/R group (PTEN KO rats treated with myocardial I/R). PTEN mRNA level was detected by reverse transcription PCR, and myocardial pathological damage was observed by HE staining. Heart rate (HR) and left ventricular wall thickness (LVWT) were measured by echocardiography, and left ventricular systolic blood pressure (LVSP), left ventricular ejection fraction (LVEF), and fraction shortening (FS) were recorded by BL-420F bioassay system. Serum creatine kinase isoenzyme (CK-MB), myoglobin (Mb) and cardiac troponin I (cTnI) were detected by ELISA. Western blot analysis was used to detect the protein expression of NLRP3, embryonic lethal, abnormal vision, Drosophila-like 1 (ELAVL1), caspase-1 (caspase-1), and IL-1ß in heart tissues. Immunohistochemical staining was performed to detect the content of caspase-1 in cardiac tissues. Apoptosis of myocardial tissue was observed with TUNEL staining. Results Compared with the sham operation group, PTEN mRNA and protein levels in the wild-type I/R group significantly increased, HR, LVSP, LVEF, FS, and LVWT went down significantly, and serum CK-MB, Mb, and cTnI levels significantly increased, and NLRP3, ELAVL1, caspase-1, and IL-1ß protein expression levels went up significantly. After PTEN was knocked out, PTEN mRNA and protein levels were significantly reduced, the pathological damage of cardiomyocytes was alleviated, and HR, LVSP, LVEF, FS, and LVWT were significantly elevated, and serum CK-MB, Mb, and cTnI levels were significantly inhibited. NLRP3, ELAVL1, caspase-1, and IL-1ß protein levels and the number of apoptotic cardiomyocytes were significantly reduced after PTEN knockout. Conclusion Knockout of PTEN can alleviate the pathological damage of myocardium and inhibit nlrp3-mediated apoptosis of cardiomyocytes, indicating that knockout of PTEN can alleviate myocardial I/R damage.


Assuntos
Isquemia Miocárdica/genética , Miócitos Cardíacos/citologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , PTEN Fosfo-Hidrolase/genética , Piroptose , Traumatismo por Reperfusão/genética , Animais , Técnicas de Inativação de Genes , Ratos , Volume Sistólico , Função Ventricular Esquerda
13.
PLoS Genet ; 16(5): e1008782, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32421721

RESUMO

The planar cell polarity pathway is required for heart development and whilst the functions of most pathway members are known, the roles of the jnk genes in cardiac morphogenesis remain unknown as mouse mutants exhibit functional redundancy, with early embryonic lethality of compound mutants. In this study zebrafish were used to overcome early embryonic lethality in mouse models and establish the requirement for Jnk in heart development. Whole mount in-situ hybridisation and RT-PCR demonstrated that evolutionarily conserved alternative spliced jnk1a and jnk1b transcripts were expressed in the early developing heart. Maternal zygotic null mutant zebrafish lines for jnk1a and jnk1b, generated using CRISPR-Cas9, revealed a requirement for jnk1a in formation of the proximal, first heart field (FHF)-derived portion of the cardiac ventricular chamber. Rescue of the jnk1a mutant cardiac phenotype was only possible by injection of the jnk1a EX7 Lg alternatively spliced transcript. Analysis of mutants indicated that there was a reduction in the size of the hand2 expression field in jnk1a mutants which led to a specific reduction in FHF ventricular cardiomyocytes within the anterior lateral plate mesoderm. Moreover, the jnk1a mutant ventricular defect could be rescued by injection of hand2 mRNA. This study reveals a novel and critical requirement for Jnk1 in heart development and highlights the importance of alternative splicing in vertebrate cardiac morphogenesis. Genetic pathways functioning through jnk1 may be important in human heart malformations with left ventricular hypoplasia.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ventrículos do Coração/citologia , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Processamento Alternativo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Contagem de Células , Células Cultivadas , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Ventrículos do Coração/embriologia , Ventrículos do Coração/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
14.
Nat Commun ; 11(1): 2585, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444791

RESUMO

Cardiac maturation lays the foundation for postnatal heart development and disease, yet little is known about the contributions of the microenvironment to cardiomyocyte maturation. By integrating single-cell RNA-sequencing data of mouse hearts at multiple postnatal stages, we construct cellular interactomes and regulatory signaling networks. Here we report switching of fibroblast subtypes from a neonatal to adult state and this drives cardiomyocyte maturation. Molecular and functional maturation of neonatal mouse cardiomyocytes and human embryonic stem cell-derived cardiomyocytes are considerably enhanced upon co-culture with corresponding adult cardiac fibroblasts. Further, single-cell analysis of in vivo and in vitro cardiomyocyte maturation trajectories identify highly conserved signaling pathways, pharmacological targeting of which substantially delays cardiomyocyte maturation in postnatal hearts, and markedly enhances cardiomyocyte proliferation and improves cardiac function in infarcted hearts. Together, we identify cardiac fibroblasts as a key constituent in the microenvironment promoting cardiomyocyte maturation, providing insights into how the manipulation of cardiomyocyte maturity may impact on disease development and regeneration.


Assuntos
Fibroblastos/fisiologia , Infarto do Miocárdio/patologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Meios de Cultivo Condicionados/farmacologia , Feminino , Fibroblastos/citologia , Coração/crescimento & desenvolvimento , Humanos , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Análise de Célula Única
15.
PLoS Genet ; 16(5): e1008818, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32469866

RESUMO

The Hippo signalling pathway and its central effector YAP regulate proliferation of cardiomyocytes and growth of the heart. Using genetic models in mice we show that the increased proliferation of embryonal and postnatal cardiomyocytes due to loss of the Hippo-signaling component SAV1 depends on the Myb-MuvB (MMB) complex. Similarly, proliferation of postnatal cardiomyocytes induced by constitutive active YAP requires MMB. Genome studies revealed that YAP and MMB regulate an overlapping set of cell cycle genes in cardiomyocytes. Protein-protein interaction studies in cell lines and with recombinant proteins showed that YAP binds directly to B-MYB, a subunit of MMB, in a manner dependent on the YAP WW domains and a PPXY motif in B-MYB. Disruption of the interaction by overexpression of the YAP binding domain of B-MYB strongly inhibits the proliferation of cardiomyocytes. Our results point to MMB as a critical downstream effector of YAP in the control of cardiomyocyte proliferation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/genética , Miócitos Cardíacos/citologia , Transativadores/química , Transativadores/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Animais Recém-Nascidos , Sítios de Ligação , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proliferação de Células , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Camundongos , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Miócitos Cardíacos/química , Regiões Promotoras Genéticas , Ratos
16.
PLoS One ; 15(5): e0232715, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369512

RESUMO

PIWI-interacting RNAs (piRNAs) are a class of non-coding RNAs initially thought to be restricted exclusively to germline cells. In recent years, accumulating evidence has demonstrated that piRNAs are actually expressed in pluripotent, neural, cardiac and even cancer cells. However, controversy remains around the existence and function of somatic piRNAs. Using small RNA-seq samples from H9 pluripotent cells differentiated to mesoderm progenitors and cardiomyocytes we identified the expression of 447 piRNA transcripts, of which 241 were detected in pluripotency, 218 in mesoderm and 171 in cardiac cells. The majority of them originated from the sense strand of protein coding and lncRNAs genes in all stages of differentiation, though no evidences of amplification loop (ping-pong) were found. Genes hosting piRNA transcripts in cardiac samples were related to critical biological processes in the heart, like contraction and cardiac muscle development. Our results indicate that these piRNAs might have a role in fine-tuning the expression of genes involved in differentiation of pluripotent cells to cardiomyocytes.


Assuntos
Células-Tronco Embrionárias Humanas/citologia , Miócitos Cardíacos/citologia , RNA Interferente Pequeno/genética , Adulto , Diferenciação Celular , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/metabolismo
17.
Life Sci ; 255: 117817, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32446845

RESUMO

Glucocorticoids can promote cardiomyocyte maturation. However, the mechanism underlying glucocorticoid-mediated cardiomyocyte maturation is still unclear. Mitophagy plays a key role in cardiomyocyte maturation. Based on current knowledge, our study evaluated the effects of the glucocorticoid dexamethasone (100 nM) on the maturation of mouse embryonic stem cell-derived cardiomyocytes and the role of mitophagy in this maturation. The results showed that dexamethasone can promote embryonic stem cell-derived cardiomyocyte maturation, inhibit cardiomyocyte proliferation, and promote myocardial fiber arrangement. However, dexamethasone did not affect mitochondrial morphology in cardiomyocytes. Glucocorticoid receptor inhibitors (RU486, 1 nM) can inhibit dexamethasone-mediated cardiomyocyte maturation. Additionally, dexamethasone can promote mitophagy in embryonic stem cell-derived cardiomyocytes and induce LC3 and lysosomal aggregation in mitochondria. The inhibition of mitophagy can inhibit the cardiomyocyte maturation effect of dexamethasone. Furthermore, our research found that dexamethasone may mediate the occurrence of mitophagy in cardiomyocytes through Parkin. The siRNA-mediated inhibition of Parkin expression can inhibit mitochondrial autophagy caused by dexamethasone, thus inhibiting cardiomyocyte maturation. Overall, our study found that dexamethasone can promote embryonic stem cell-derived cardiomyocyte maturation through Parkin-mediated mitophagy.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Mitofagia/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/citologia , RNA Interferente Pequeno/administração & dosagem , Receptores de Glucocorticoides/metabolismo
18.
Arch Biochem Biophys ; 690: 108430, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32473132

RESUMO

BACKGROUND: The severity and duration of hypoxia is known to determine apoptotic fate in heart; however, its implication during myocardial infarction (MI) remains unaddressed. Therefore the aim of the study was to determine apoptotic regulation in cardiomyocytes under varied hypoxic intensity and duration and to unravel the role of HIF-1α in such modulation. METHODS: Treatment of cardiomyocytes to varied hypoxic intensity and duration was carried out in vitro, which was mimicked in vivo by dose-dependent Isoproterenol hydrochloride treatment for varied time-points. Myocardium-targeted HIF-1α knockdown in vivo was performed to decipher its role in cardiomyocyte apoptosis under varied stress. Signaling intermediates were analyzed by RT-PCR, immunoblotting and co-immunoprecipitation. DCFDA-based ROS assay, Griess assay for NO release and biochemical assays for estimating caspase activity were performed. RESULTS: Severe stress resulted in cardiomyocyte apoptosis in both shorter and longer time-points. Moderate stress, on the other hand, induced apoptosis only in the shorter time-point which was downregulated in the longer time-point. ROS activity was upregulated under severe hypoxic stress for both time-points and only in the early time-point under moderate hypoxia. Increased ROS accumulation activated ERK-1/2 which stabilized nuclear HIF-1α, promoting bnip3-mediated apoptosis. Stable HSP90-IRE-1 association in such cells caused elevated endoplasmic reticulum stress-related caspase-12 activity. Sustained moderate hypoxia caused decline in ROS activity, but upregulated NFκB-dependent NO generation. NO-stabilized HIF-1α was predominantly cytosolic, since low ROS levels downregulated ERK-1/2 activity, thereby suppressing bnip3 expression. Cytosolic HIF-1α in such cells sequestered HSP90 from IRE-1, downregulating caspase-12 activity due to proteasomal degradation of IRE-1. Accordingly, myocardium-specific in vivo silencing of HIF-1α was beneficial at both time-points under severe stress as also for lesser duration of moderate stress. However, silencing of HIF-1α aggravated apoptotic injury during sustained moderate stress. CONCLUSION: ROS-mediated HIF-1α stabilization promotes cardiomyocyte apoptosis on one hand while NO-mediated stabilization of HIF-1α disrupts apoptosis depending upon the severity and duration of hypoxia. Therefore the outcome of modulation of cardiac HIF-1α activity is regulated by both the severity and duration of ischemic stress.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Infarto do Miocárdio/fisiopatologia , Animais , Apoptose , Caspase 12/metabolismo , Hipóxia Celular , Linhagem Celular , Estresse do Retículo Endoplasmático , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Mutação , Miócitos Cardíacos/citologia , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Fatores de Tempo , Transfecção
19.
J Vis Exp ; (159)2020 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-32449745

RESUMO

The isolation of ventricular cardiac myocytes from animal and human hearts is a fundamental method in cardiac research. Animal cardiomyocytes are commonly isolated by coronary perfusion with digestive enzymes. However, isolating human cardiomyocytes is challenging because human myocardial specimens usually do not allow for coronary perfusion, and alternative isolation protocols result in poor yields of viable cells. In addition, human myocardial specimens are rare and only regularly available at institutions with on-site cardiac surgery. This hampers the translation of findings from animal to human cardiomyocytes. Described here is a reliable protocol that enables efficient isolation of ventricular myocytes from human and animal myocardium. To increase the surface-to-volume ratio while minimizing cell damage, myocardial tissue slices 300 µm thick are generated from myocardial specimens with a vibratome. Tissue slices are then digested with protease and collagenase. Rat myocardium was used to establish the protocol and quantify yields of viable, calcium-tolerant myocytes by flow-cytometric cell counting. Comparison with the commonly used tissue-chunk method showed significantly higher yields of rod-shaped cardiomyocytes (41.5 ± 11.9 vs. 7.89 ± 3.6%, p < 0.05). The protocol was translated to failing and non-failing human myocardium, where yields were similar as in rat myocardium and, again, markedly higher than with the tissue-chunk method (45.0 ± 15.0 vs. 6.87 ± 5.23 cells/mg, p < 0.05). Notably, with the protocol presented it is possible to isolate reasonable numbers of viable human cardiomyocytes (9-200 cells/mg) from minimal amounts of tissue (<50 mg). Thus, the method is applicable to healthy and failing myocardium from both human and animal hearts. Furthermore, it is possible to isolate excitable and contractile myocytes from human tissue specimens stored for up to 36 h in cold cardioplegic solution, rendering the method particularly useful for laboratories at institutions without on-site cardiac surgery.


Assuntos
Separação Celular/métodos , Ventrículos do Coração/citologia , Miocárdio/citologia , Miócitos Cardíacos/citologia , Potenciais de Ação , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Sobrevivência Celular , Feminino , Humanos , Perfusão , Ratos Wistar , Reprodutibilidade dos Testes
20.
Nat Commun ; 11(1): 2039, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341350

RESUMO

Long non-coding RNAs (lncRNAs) contribute to cardiac (patho)physiology. Aging is the major risk factor for cardiovascular disease with cardiomyocyte apoptosis as one underlying cause. Here, we report the identification of the aging-regulated lncRNA Sarrah (ENSMUST00000140003) that is anti-apoptotic in cardiomyocytes. Importantly, loss of SARRAH (OXCT1-AS1) in human engineered heart tissue results in impaired contractile force development. SARRAH directly binds to the promoters of genes downregulated after SARRAH silencing via RNA-DNA triple helix formation and cardiomyocytes lacking the triple helix forming domain of Sarrah show an increase in apoptosis. One of the direct SARRAH targets is NRF2, and restoration of NRF2 levels after SARRAH silencing partially rescues the reduction in cell viability. Overexpression of Sarrah in mice shows better recovery of cardiac contractile function after AMI compared to control mice. In summary, we identified the anti-apoptotic evolutionary conserved lncRNA Sarrah, which is downregulated by aging, as a regulator of cardiomyocyte survival.


Assuntos
Apoptose , Infarto do Miocárdio/genética , Miócitos Cardíacos/citologia , RNA Longo não Codificante/genética , Envelhecimento , Animais , Proteínas de Transporte/genética , Sobrevivência Celular , Coenzima A-Transferases/genética , Modelos Animais de Doenças , Inativação Gênica , Humanos , Proteínas com Domínio LIM/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , RNA Antissenso/genética , RNA Interferente Pequeno/genética , Fatores de Transcrição de p300-CBP/genética
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