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1.
Nat Commun ; 11(1): 4664, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938919

RESUMO

Cardiorenal syndrome type 4 (CRS4) is a common complication of chronic kidney disease (CKD), but the pathogenic mechanisms remain elusive. Here we report that morphological and functional changes in myocardial mitochondria are observed in CKD mice, especially decreases in oxidative phosphorylation and fatty acid metabolism. High phosphate (HP), a hallmark of CKD, contributes to myocardial energy metabolism dysfunction by downregulating peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α). Furthermore, the transcriptional factor interferon regulatory factor 1 (IRF1) is revealed as the key molecule upregulated by HP through histone H3K9 acetylation, and responsible for the HP-mediated transcriptional inhibition of PGC1α by directly binding to its promoter region. Conversely, restoration of PGC1α expression or genetic knockdown of IRF1 significantly attenuates HP-induced alterations in vitro and in vivo. These findings demonstrate that IRF1-PGC1α axis-mediated myocardial energy metabolism remodeling plays a crucial role in the pathogenesis of CRS4.


Assuntos
Síndrome Cardiorrenal/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Síndrome Cardiorrenal/patologia , Modelos Animais de Doenças , Regulação para Baixo , Metabolismo Energético , Técnicas de Silenciamento de Genes , Taxa de Filtração Glomerular , Glucuronidase/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Humanos , Fator Regulador 1 de Interferon/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fosfatos/metabolismo , Regiões Promotoras Genéticas , Ratos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo , Adulto Jovem
2.
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
3.
Nat Commun ; 11(1): 4364, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868781

RESUMO

Pathophysiological roles of cardiac dopamine system remain unknown. Here, we show the role of dopamine D1 receptor (D1R)-expressing cardiomyocytes (CMs) in triggering heart failure-associated ventricular arrhythmia. Comprehensive single-cell resolution analysis identifies the presence of D1R-expressing CMs in both heart failure model mice and in heart failure patients with sustained ventricular tachycardia. Overexpression of D1R in CMs disturbs normal calcium handling while CM-specific deletion of D1R ameliorates heart failure-associated ventricular arrhythmia. Thus, cardiac D1R has the potential to become a therapeutic target for preventing heart failure-associated ventricular arrhythmia.


Assuntos
Arritmias Cardíacas/etiologia , Insuficiência Cardíaca , Miócitos Cardíacos/metabolismo , Receptores de Dopamina D1/metabolismo , Animais , Arritmias Cardíacas/prevenção & controle , Perfilação da Expressão Gênica/métodos , Humanos , Camundongos , Camundongos Transgênicos , Ratos , Receptores de Dopamina D1/genética , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/prevenção & controle
4.
Vasc Health Risk Manag ; 16: 353-365, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982263

RESUMO

Among the vast number of noncommunicable diseases encountered worldwide, cardiovascular diseases accounted for about 17.8 million deaths in 2017 and ischemic heart disease (IHD) remains the single-largest cause of death in countries across all income groups. Because conventional medications are not without shortcomings and patients still refractory to these medications, scientific investigation is ongoing to advance the management of IHD, and shows a great promise for better treatment modalities, but additional research can warrant improvement in terms of the quality of life of patients. Metabolic modulation is one promising strategy for the treatment of IHD, because alterations in energy metabolism are involved in progression of the disease. Therefore, the purpose of this review was to strengthen attention toward the use of metabolic modulators and to review the current level of knowledge on cardiac energy metabolic pathways.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Animais , Humanos , Mitocôndrias Cardíacas/metabolismo , Terapia de Alvo Molecular , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Miócitos Cardíacos/metabolismo
5.
Nature ; 585(7826): 603-608, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939090

RESUMO

Ferroptosis-an iron-dependent, non-apoptotic cell death process-is involved in various degenerative diseases and represents a targetable susceptibility in certain cancers1. The ferroptosis-susceptible cell state can either pre-exist in cells that arise from certain lineages or be acquired during cell-state transitions2-5. However, precisely how susceptibility to ferroptosis is dynamically regulated remains poorly understood. Here we use genome-wide CRISPR-Cas9 suppressor screens to identify the oxidative organelles peroxisomes as critical contributors to ferroptosis sensitivity in human renal and ovarian carcinoma cells. Using lipidomic profiling we show that peroxisomes contribute to ferroptosis by synthesizing polyunsaturated ether phospholipids (PUFA-ePLs), which act as substrates for lipid peroxidation that, in turn, results in the induction of ferroptosis. Carcinoma cells that are initially sensitive to ferroptosis can switch to a ferroptosis-resistant state in vivo in mice, which is associated with extensive downregulation of PUFA-ePLs. We further find that the pro-ferroptotic role of PUFA-ePLs can be extended beyond neoplastic cells to other cell types, including neurons and cardiomyocytes. Together, our work reveals roles for the peroxisome-ether-phospholipid axis in driving susceptibility to and evasion from ferroptosis, highlights PUFA-ePL as a distinct functional lipid class that is dynamically regulated during cell-state transitions, and suggests multiple regulatory nodes for therapeutic interventions in diseases that involve ferroptosis.


Assuntos
Éteres/metabolismo , Ferroptose , Peroxissomos/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Diferenciação Celular , Linhagem Celular , Éteres/química , Feminino , Edição de Genes , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Peroxidação de Lipídeos , Masculino , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Peroxissomos/genética
6.
PLoS One ; 15(8): e0236457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790682

RESUMO

Transgenic mice with selective induction of calreticulin transgene expression in cardiomyocytes (CardiacCRT+) were analyzed. CardiacCRT+ cardiomyocytes showed increased contractility and Ca2+ transients. Yet, in vivo assessment of cardiac performance, and ischemic tolerance of CardiacCRT+ mice demonstrated right ventricle dilation and reduced cardiac output, increased QT interval and decreased P amplitude. Paradoxically, ex vivo working hearts from CardiacCRT+ mice showed enhanced ischemic cardio-protection and cardiac efficiency. Under aerobic conditions, CardiacCRT+ hearts showed less efficient cardiac function than sham control hearts due to an increased ATP production from glycolysis relative to glucose oxidation. During reperfusion, this inefficiency was reversed, with CardiacCRT+ hearts exhibiting better functional recovery and increased cardiac efficiency compared to sham control hearts. On the other hand, mechanical stretching of isolated cardiac fibroblasts activated the IRE1α branch of the unfolded protein response pathway as well as induction of Col1A2 and TGFß gene expression ex vivo, which were all suppressed by tauroursodeoxycholic acid.


Assuntos
Calreticulina/metabolismo , Contração Miocárdica , Isquemia Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Calreticulina/genética , Células Cultivadas , Metabolismo Energético , Frequência Cardíaca , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Isquemia Miocárdica/genética , Isquemia Miocárdica/fisiopatologia , Miócitos Cardíacos/patologia , Regulação para Cima
7.
PLoS One ; 15(8): e0231806, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817622

RESUMO

The cAMP-dependent protein kinase (PKA) signaling pathway is the primary means by which the heart regulates moment-to-moment changes in contractility and metabolism. We have previously found that PKA signaling is dysfunctional in the diabetic heart, yet the underlying mechanisms are not fully understood. The objective of this study was to determine if decreased insulin signaling contributes to a dysfunctional PKA response. To do so, we isolated adult cardiomyocytes (ACMs) from wild type and Akita type 1 diabetic mice. ACMs were cultured in the presence or absence of insulin and PKA signaling was visualized by immunofluorescence microscopy using an antibody that recognizes proteins specifically phosphorylated by PKA. We found significant decreases in proteins phosphorylated by PKA in wild type ACMs cultured in the absence of insulin. PKA substrate phosphorylation was decreased in Akita ACMs, as compared to wild type, and unresponsive to the effects of insulin. The decrease in PKA signaling was observed regardless of whether the kinase was stimulated with a beta-agonist, a cell-permeable cAMP analog, or with phosphodiesterase inhibitors. PKA content was unaffected, suggesting that the decrease in PKA signaling may be occurring by the loss of specific PKA substrates. Phospho-specific antibodies were used to discern which potential substrates may be sensitive to the loss of insulin. Contractile proteins were phosphorylated similarly in wild type and Akita ACMs regardless of insulin. However, phosphorylation of the glycolytic regulator, PFK-2, was significantly decreased in an insulin-dependent manner in wild type ACMs and in an insulin-independent manner in Akita ACMs. These results demonstrate a defect in PKA activation in the diabetic heart, mediated in part by deficient insulin signaling, that results in an abnormal activation of a primary metabolic regulator.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Insulina/metabolismo , Insulina/farmacologia , Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/fisiologia , Inibidores de Fosfodiesterase/farmacologia , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos
8.
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
9.
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
10.
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
11.
Nature ; 584(7820): 279-285, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760005

RESUMO

In pathophysiology, reactive oxygen species oxidize biomolecules that contribute to disease phenotypes1. One such modification, 8-oxoguanine2 (o8G), is abundant in RNA3 but its epitranscriptional role has not been investigated for microRNAs (miRNAs). Here we specifically sequence oxidized miRNAs in a rat model of the redox-associated condition cardiac hypertrophy4. We find that position-specific o8G modifications are generated in seed regions (positions 2-8) of selective miRNAs, and function to regulate other mRNAs through o8G•A base pairing. o8G is induced predominantly at position 7 of miR-1 (7o8G-miR-1) by treatment with an adrenergic agonist. Introducing 7o8G-miR-1 or 7U-miR-1 (in which G at position 7 is substituted with U) alone is sufficient to cause cardiac hypertrophy in mice, and the mRNA targets of o8G-miR-1 function in affected phenotypes; the specific inhibition of 7o8G-miR-1 in mouse cardiomyocytes was found to attenuate cardiac hypertrophy. o8G-miR-1 is also implicated in patients with cardiomyopathy. Our findings show that the position-specific oxidation of miRNAs could serve as an epitranscriptional mechanism to coordinate pathophysiological redox-mediated gene expression.


Assuntos
Cardiomegalia/genética , Cardiomegalia/patologia , Inativação Gênica , MicroRNAs/química , MicroRNAs/metabolismo , Animais , Pareamento de Bases , Linhagem Celular , Modelos Animais de Doenças , Guanina/análogos & derivados , Guanina/análise , Guanina/química , Guanina/metabolismo , Humanos , Camundongos , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Oxirredução , Ratos , Transcrição Genética/genética , Transcriptoma/genética
12.
Life Sci ; 259: 118199, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32781064

RESUMO

Cellular senescence, a process whereby cells enter a state of permanent growth arrest, appears to regulate cardiac pathological remodeling and dysfunction in response to various stresses including myocardial infarction (MI). However, the precise role as well as the underlying regulatory mechanism of cardiac cellular senescence in the ischemic heart disease remain to be further determined. Herein we report an inhibitory role of Nrf2, a key transcription factor of cellular defense, in regulating cardiac senescence in infarcted hearts as well as a therapeutic potential of targeting Nrf2-mediated suppression of cardiac senescence in the treatment of MI-induced cardiac dysfunction. MI was induced by left coronary artery ligation for 28 days in mice. Heart tissues from the infarct border zone were used for the analyses. The MI-induced cardiac dysfunction was associated with increased myocardial cell senescence, oxidative stress and apoptosis in adult wild type (WT) mice. In addition, a downregulated Nrf2 activity was associated with upregulated Keap1 levels and increased phosphorylation of JAK and FYN in the infarcted border zone heart tissues. Nrf2 Knockout (Nrf2-/-) enhanced the MI-induced myocardial, cardiac dysfunction and senescence. Qiliqiangxin (QLQX), a herbal medicine which could reverse the MI-induced suppression of Nrf2 activity, significantly inhibited the MI-induced cardiac senescence, apoptosis, and cardiac dysfunction in WT mice but not in Nrf2-/- mice. These results indicate that MI downregulates Nrf2 activity thus promoting oxidative stress to accelerate cellular senescence in the infarcted heart towards cardiac dysfunction and Nrf2 may be a drug target for suppressing the cellular senescence-associated pathologies in infarcted hearts.


Assuntos
Cardiomiopatias/genética , Cardiomiopatias/patologia , Senescência Celular/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/patologia , Fator 2 Relacionado a NF-E2/genética , Animais , Cardiomiopatias/diagnóstico por imagem , Ecocardiografia , Inativação Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/diagnóstico por imagem , Miócitos Cardíacos/metabolismo , RNA Interferente Pequeno/farmacologia , Remodelação Ventricular/fisiologia
13.
Mol Syst Biol ; 16(7): e9610, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32715618

RESUMO

The novel SARS-coronavirus 2 (SARS-CoV-2) poses a global challenge on healthcare and society. For understanding the susceptibility for SARS-CoV-2 infection, the cell type-specific expression of the host cell surface receptor is necessary. The key protein suggested to be involved in host cell entry is angiotensin I converting enzyme 2 (ACE2). Here, we report the expression pattern of ACE2 across > 150 different cell types corresponding to all major human tissues and organs based on stringent immunohistochemical analysis. The results were compared with several datasets both on the mRNA and protein level. ACE2 expression was mainly observed in enterocytes, renal tubules, gallbladder, cardiomyocytes, male reproductive cells, placental trophoblasts, ductal cells, eye, and vasculature. In the respiratory system, the expression was limited, with no or only low expression in a subset of cells in a few individuals, observed by one antibody only. Our data constitute an important resource for further studies on SARS-CoV-2 host cell entry, in order to understand the biology of the disease and to aid in the development of effective treatments to the viral infection.


Assuntos
Peptidil Dipeptidase A/metabolismo , Sistema Respiratório/metabolismo , Betacoronavirus , Vasos Sanguíneos/metabolismo , Túnica Conjuntiva/metabolismo , Enterócitos/metabolismo , Feminino , Vesícula Biliar/metabolismo , Interações entre Hospedeiro e Microrganismos , Humanos , Imuno-Histoquímica , Túbulos Renais Proximais/metabolismo , Masculino , Espectrometria de Massas , Miócitos Cardíacos/metabolismo , Especificidade de Órgãos , Peptidil Dipeptidase A/genética , Placenta/metabolismo , Gravidez , RNA-Seq , Análise de Célula Única , Testículo/metabolismo
14.
Int Heart J ; 61(4): 806-814, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32728001

RESUMO

This study aimed to explore the function of miR-24 in hypoxia/reoxygenation (H/R) -induced cardiomyocyte injury.We constructed a cardiomyocyte model of H/R using the primary cardiomyocytes isolated from Sprague-Dawley rats. To explore the role of miR-24, cells were transfected with a miR-24 mimic or miR-24 inhibitor. The RNA expression levels of miR-24 and Mapk14 were determined using qRT-PCR. The proliferation and apoptosis of cells were determined using a CCK8 assay and a flow cytometer. The TargetScan website was used to predict the targets of miR-24. A dual-luciferase reporter gene assay was conducted to verify whether Mapk14 is indeed a target of miR-24. A Western blot was applied for protein detection.H/R exposure decreased the expression of miR-24 in rat cardiomyocytes. Transfection of the miR-24 mimic into cardiomyocytes reduced H/R-induced injury as evidenced by an increase in proliferation and a decrease in the apoptotic rate. By contrast, transfection of the miR-24 inhibitor aggravated H/R-induced injury. The expression of Bcl-2 was increased while the levels of Bax and Active-caspase 3 were reduced in the H/R+miR-24 mimic group compared to those in the H/R group. H/R+miR-24 inhibitor group showed the opposite results. Mapk14 was identified as a target of miR-24. The mRNA level of Mapk14 and its protein (p38 MAPK) level were negatively affected by miR-24. Furthermore, we discovered that depletion of Mapk14 reduced the promoting effect of the miR-24 inhibitor on cell apoptosis.Overall, our results illustrated that miR-24 could attenuate H/R-induced injury partly by regulating Mapk14.


Assuntos
Hipóxia/metabolismo , MicroRNAs/genética , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Apoptose/fisiologia , Caspase 3/metabolismo , Genes Reporter/genética , Genes bcl-2/genética , Humanos , Ratos , Ratos Sprague-Dawley , Transfecção/métodos , Proteína X Associada a bcl-2/metabolismo
15.
Proc Natl Acad Sci U S A ; 117(31): 18822-18831, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690703

RESUMO

Muscle contraction is regulated by the movement of end-to-end-linked troponin-tropomyosin complexes over the thin filament surface, which uncovers or blocks myosin binding sites along F-actin. The N-terminal half of troponin T (TnT), TNT1, independently promotes tropomyosin-based, steric inhibition of acto-myosin associations, in vitro. Recent structural models additionally suggest TNT1 may restrain the uniform, regulatory translocation of tropomyosin. Therefore, TnT potentially contributes to striated muscle relaxation; however, the in vivo functional relevance and molecular basis of this noncanonical role remain unclear. Impaired relaxation is a hallmark of hypertrophic and restrictive cardiomyopathies (HCM and RCM). Investigating the effects of cardiomyopathy-causing mutations could help clarify TNT1's enigmatic inhibitory property. We tested the hypothesis that coupling of TNT1 with tropomyosin's end-to-end overlap region helps anchor tropomyosin to an inhibitory position on F-actin, where it deters myosin binding at rest, and that, correspondingly, cross-bridge cycling is defectively suppressed under diastolic/low Ca2+ conditions in the presence of HCM/RCM lesions. The impact of TNT1 mutations on Drosophila cardiac performance, rat myofibrillar and cardiomyocyte properties, and human TNT1's propensity to inhibit myosin-driven, F-actin-tropomyosin motility were evaluated. Our data collectively demonstrate that removing conserved, charged residues in TNT1's tropomyosin-binding domain impairs TnT's contribution to inhibitory tropomyosin positioning and relaxation. Thus, TNT1 may modulate acto-myosin activity by optimizing F-actin-tropomyosin interfacial contacts and by binding to actin, which restrict tropomyosin's movement to activating configurations. HCM/RCM mutations, therefore, highlight TNT1's essential role in contractile regulation by diminishing its tropomyosin-anchoring effects, potentially serving as the initial trigger of pathology in our animal models and humans.


Assuntos
Cardiomiopatias/metabolismo , Mutação/genética , Tropomiosina , Troponina T , Actinas/química , Actinas/metabolismo , Animais , Cálcio/metabolismo , Diástole/genética , Diástole/fisiologia , Proteínas de Drosophila , Humanos , Miócitos Cardíacos/química , Miócitos Cardíacos/metabolismo , Ligação Proteica , Ratos , Tropomiosina/química , Tropomiosina/metabolismo , Troponina T/química , Troponina T/genética , Troponina T/metabolismo
16.
Proc Natl Acad Sci U S A ; 117(30): 18079-18090, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32647060

RESUMO

Ion channels in excitable cells function in macromolecular complexes in which auxiliary proteins modulate the biophysical properties of the pore-forming subunits. Hyperpolarization-activated, cyclic nucleotide-sensitive HCN4 channels are critical determinants of membrane excitability in cells throughout the body, including thalamocortical neurons and cardiac pacemaker cells. We previously showed that the properties of HCN4 channels differ dramatically in different cell types, possibly due to the endogenous expression of auxiliary proteins. Here, we report the discovery of a family of endoplasmic reticulum (ER) transmembrane proteins that associate with and modulate HCN4. Lymphoid-restricted membrane protein (LRMP, Jaw1) and inositol trisphosphate receptor-associated guanylate kinase substrate (IRAG, Mrvi1, and Jaw1L) are homologous proteins with small ER luminal domains and large cytoplasmic domains. Despite their homology, LRMP and IRAG have distinct effects on HCN4. LRMP is a loss-of-function modulator that inhibits the canonical depolarizing shift in the voltage dependence of HCN4 in response to the binding of cAMP. In contrast, IRAG causes a gain of HCN4 function by depolarizing the basal voltage dependence in the absence of cAMP. The mechanisms of action of LRMP and IRAG are independent of trafficking and cAMP binding, and they are specific to the HCN4 isoform. We also found that IRAG is highly expressed in the mouse sinoatrial node where computer modeling predicts that its presence increases HCN4 current. Our results suggest important roles for LRMP and IRAG in the regulation of cellular excitability, as tools for advancing mechanistic understanding of HCN4 channel function, and as possible scaffolds for coordination of signaling pathways.


Assuntos
Retículo Endoplasmático/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetulus , AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/química , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Masculino , Potenciais da Membrana/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Modelos Biológicos , Família Multigênica , Miócitos Cardíacos/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas , Nó Sinoatrial/fisiologia , Nó Sinoatrial/fisiopatologia
17.
Ther Adv Cardiovasc Dis ; 14: 1753944720934937, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32611276

RESUMO

Ivabradine is a pure heart-rate lowering drug that is nowadays used, accordingly to the last ESC Guidelines, to reduce mortality and heart failure (HF) hospitalization in patients with HF with reduced ejection fraction and in symptomatic patiens with inappropriate sinus tachycardia. Moreover, interesting effect of ivabradine on endothelial and myocardial function and on oxidative stress and inflamation pathways are progressively emerging. The aim of this paper is to highlight newer evidences about ivabradine effect (and consequently possible future application of the drug) in pathological settings different from guidelines-based clinical practice.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Ivabradina/uso terapêutico , Animais , Função Atrial/efeitos dos fármacos , Fármacos Cardiovasculares/efeitos adversos , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Ivabradina/efeitos adversos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Função Ventricular/efeitos dos fármacos
18.
Life Sci ; 257: 118047, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32629001

RESUMO

AIM: The purpose of the study was to investigate what effects the sigma-1 receptor (S1R) could exert on the cardiac myocyte ion channels in a rodent model of depression and to explore the underlying mechanisms since depression is an independent risk factor for cardiovascular diseases including ventricular arrhythmias (VAs). MATERIALS AND METHODS: To establish the depression model in rats, chronic mild unpredictable stress (CMUS) for 28 days was used. The S1R agonist fluvoxamine was injected intraperitoneally from the second week to the last week for 21 days in total, and the effects were evaluated by patch clamp, western blot analysis, and Masson staining. KEY FINDINGS: We demonstrated that depression was improved after treatment with fluvoxamine. In addition, the prolongation of the corrected QT (QTc) interval under CMUS that increased vulnerability to VAs was significantly attenuated by stimulation of S1R due to the decreased amplitude of L-type calcium current (ICa-L) and the restoration of reduced transient outward potassium current (Ito) resulting from CMUS induction. The S1R also decelerated Ito inactivation and accelerated Ito recovery by activating Ca2+/calmodulin-dependent kinase II. Moreover, the stimulation of S1R ameliorated the structural remodeling as the substrate for maintenance of VAs. All these effects were abolished by the administration of S1R antagonist BD1047, which verified the roles for S1R. SIGNIFICANCE: Activation of S1R could decrease the vulnerability to VAs by inhibiting ICa-L and restoring Ito, in addition to ameliorating the CMUS-induced depressive symptoms and structural remodeling.


Assuntos
Depressão/metabolismo , Miócitos Cardíacos/metabolismo , Receptores sigma/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/metabolismo , Depressão/fisiopatologia , Transtorno Depressivo/metabolismo , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Fluvoxamina/metabolismo , Fluvoxamina/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores sigma/metabolismo , Remodelação Ventricular/efeitos dos fármacos , Remodelação Ventricular/fisiologia
19.
Arch Biochem Biophys ; 690: 108506, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679197

RESUMO

A new bisepoxylignan dendranlignan A (A1) and the known compound lantibeside D (D2) was isolated from Chrysanthemum Flower, the dried capitulum of Dendranthema morifolium (Ramat.) kitam. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-NMR, 2D-NMR and MS data. Additionally, A1 and D2 were evaluated for their effects on the production of inflammatory mediators in H9c2 cardiomyocytes stimulated with lipopolysaccharide (LPS). Results demonstrated that A1 and D2 decreased LPS-induced production of inflammatory cytokines TNF-α, IL-2 and IFN-γ in H9c2 cells. Both compounds also decreased the nuclear localization of c-JUN, p-P65 and p-IRF3, but did not affect the level of TLR4. Molecular docking indicated that A1 and D2 occupied the ligand binding sites of TLR4-MD2. In the present study, we for the first time discovered a new bisepoxylignan compound A1, and found that this compound has a potential to inhibit inflammation by inhibiting TLR4 signaling.


Assuntos
Chrysanthemum/química , Flores/química , Mediadores da Inflamação/metabolismo , Extratos Vegetais/química , Poli-Inos/química , Receptor 4 Toll-Like/metabolismo , Animais , Citocinas/química , Descoberta de Drogas , Humanos , Inflamação/metabolismo , Lipopolissacarídeos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Miócitos Cardíacos/metabolismo , Poli-Inos/farmacologia , Transdução de Sinais , Relação Estrutura-Atividade
20.
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
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