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1.
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
2.
Arch Biochem Biophys ; 689: 108405, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32439330

RESUMO

Cardiac hypertrophy is an adaptive response to hemodynamic stress to compensate for cardiac dysfunction. MicroRNAs can regulate cardiac function and play a vital role in the regulation of cardiac hypertrophy. In the current study, in vivo and vitro hypertrophy models are established to explore the role of miR-27b and to elucidate the underlying mechanism in cardiac hypertrophy. Expression of miR-27b was down-regulated in mice with cardiac hypertrophy. The cardiac function of the mice with cardiac hypertrophy could be restored with the overexpression of miR-27b, this is observed in terms of decreasing LVEDd, LVESd, and increasing LVFS, LVEF. This study also predicted and confirmed that galectin-3 is a target gene of miR-27b. Depletion of galectin-3 significantly attenuated hypertrophy of hearts in both in vitro and in vivo tests. In conclusion, MiR-27b be used to exert a protective role against cardiac dysfunction and hypertrophy by decreasing the expression level of galectin-3. The methodology suggested in this study provides a novel therapeutic strategy against cardiac hypertrophy.


Assuntos
Cardiomegalia/genética , Galectina 3/genética , MicroRNAs/genética , Miócitos Cardíacos/patologia , Animais , Cardiomegalia/patologia , Células Cultivadas , Regulação para Baixo , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Regulação para Cima
3.
Adv Exp Med Biol ; 1229: 149-161, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285410

RESUMO

Non-coding RNA (ncRNA) is a class of RNAs that are not act as translational protein templates. They are involved in the regulation of gene transcription, RNA maturation and protein translation, participating in a variety of physiological and physiological processes. NcRNAs have important functions, and are recently one of the hotspots in biomedical research. Cardiac hypertrophy is classified into physiological cardiac hypertrophy and pathological cardiac hypertrophy. Different from pathological cardiac hypertrophy, physiological cardiac hypertrophy usually developed during exercise, pregnancy, normal postnatal growth, accompanied with preservation or improvement of systolic function, while no cardiac fibrosis. In this chapter, we will briefly introduce the definition, characteristics, and functions of ncRNAs, including miRNAs, lncRNAs, and circRNAs, as well as a summary of the existing bioinformatics online databases which commonly used in the study of ncRNAs. Specially, this chapter will be focused on the characteristics and the underlying mechanisms about physiological cardiac hypertrophy. Furthermore, the regulatory mechanism of ncRNAs in physiological hypertrophy and the latest research progress will be summarized. Taken together, exploring physiologic cardiac hypertrophy-specific ncRNAs might be a unique research perspective that provides new point of view for interventions in heart failure and other cardiovascular diseases.


Assuntos
Cardiomegalia , RNA não Traduzido , Cardiomegalia/genética , Humanos , MicroRNAs , RNA Circular , RNA Longo não Codificante
4.
Clin Sci (Lond) ; 134(3): 359-377, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31985010

RESUMO

Hypertensive cardiac hypertrophy (HCH) is a common cause of heart failure (HF), a major public health problem worldwide. However, the molecular bases of HCH have not been completely elucidated. Neuron-derived orphan receptor-1 (NOR-1) is a nuclear receptor whose role in cardiac remodelling is poorly understood. The aim of the present study was to generate a transgenic mouse over-expressing NOR-1 in the heart (TgNOR-1) and assess the impact of this gain-of-function on HCH. The CAG promoter-driven transgenesis led to viable animals that over-expressed NOR-1 in the heart, mainly in cardiomyocytes and also in cardiofibroblasts. Cardiomyocytes from TgNOR-1 exhibited an enhanced cell surface area and myosin heavy chain 7 (Myh7)/Myh6 expression ratio, and increased cell shortening elicited by electric field stimulation. TgNOR-1 cardiofibroblasts expressed higher levels of myofibroblast markers than wild-type (WT) cells (α 1 skeletal muscle actin (Acta1), transgelin (Sm22α)) and were more prone to synthesise collagen and migrate. TgNOR-1 mice experienced an age-associated remodelling of the left ventricle (LV). Angiotensin II (AngII) induced the cardiac expression of NOR-1, and NOR-1 transgenesis exacerbated AngII-induced cardiac hypertrophy and fibrosis. This effect was associated with the up-regulation of hypertrophic (brain natriuretic peptide (Bnp), Acta1 and Myh7) and fibrotic markers (collagen type I α 1 chain (Col1a1), Pai-1 and lysyl oxidase-like 2 (Loxl2)). NOR-1 transgenesis up-regulated two key genes involved in cardiac hypertrophy (Myh7, encoding for ß-myosin heavy chain (ß-MHC)) and fibrosis (Loxl2, encoding for the extracellular matrix (ECM) modifying enzyme, Loxl2). Interestigly, in transient transfection assays, NOR-1 drove the transcription of Myh7 and Loxl2 promoters. Our findings suggest that NOR-1 is involved in the transcriptional programme leading to HCH.


Assuntos
Cardiomegalia/genética , Cardiomegalia/patologia , Progressão da Doença , Regulação da Expressão Gênica , Miocárdio/patologia , Membro 3 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Angiotensina II , Animais , Biomarcadores/metabolismo , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/fisiopatologia , Colágeno/metabolismo , Modelos Animais de Doenças , Eletrocardiografia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Humanos , Inflamação/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Transcrição Genética , Remodelação Ventricular
5.
Circ Res ; 126(4): 456-470, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31896304

RESUMO

RATIONALE: Lipid overload-induced heart dysfunction is characterized by cardiomyocyte death, myocardial remodeling, and compromised contractility, but the impact of excessive lipid supply on cardiac function remains poorly understood. OBJECTIVE: To investigate the regulation and function of the mitochondrial fission protein Drp1 (dynamin-related protein 1) in lipid overload-induced cardiomyocyte death and heart dysfunction. METHODS AND RESULTS: Mice fed a high-fat diet (HFD) developed signs of obesity and type II diabetes mellitus, including hyperlipidemia, hyperglycemia, hyperinsulinemia, and hypertension. HFD for 18 weeks also induced heart hypertrophy, fibrosis, myocardial insulin resistance, and cardiomyocyte death. HFD stimulated mitochondrial fission in mouse hearts. Furthermore, HFD increased the protein level, phosphorylation (at the activating serine 616 sites), oligomerization, mitochondrial translocation, and GTPase activity of Drp1 in mouse hearts, indicating that Drp1 was activated. Monkeys fed a diet high in fat and cholesterol for 2.5 years also exhibited myocardial damage and Drp1 activation in the heart. Interestingly, HFD decreased nicotinamide adenine dinucleotide (oxidized) levels and increased Drp1 acetylation in the heart. In adult cardiomyocytes, palmitate increased Drp1 acetylation, phosphorylation, and protein levels, and these increases were abolished by restoration of the decreased nicotinamide adenine dinucleotide (oxidized) level. Proteomics analysis and in vitro screening revealed that Drp1 acetylation at lysine 642 (K642) was increased by HFD in mouse hearts and by palmitate incubation in cardiomyocytes. The nonacetylated Drp1 mutation (K642R) attenuated palmitate-induced Drp1 activation, its interaction with voltage-dependent anion channel 1, mitochondrial fission, contractile dysfunction, and cardiomyocyte death. CONCLUSIONS: These findings uncover a novel mechanism that contributes to lipid overload-induced heart hypertrophy and dysfunction. Excessive lipid supply created an intracellular environment that facilitated Drp1 acetylation, which, in turn, increased its activity and mitochondrial translocation, resulting in cardiomyocyte dysfunction and death. Thus, Drp1 may be a critical mediator of lipid overload-induced heart dysfunction as well as a potential target for therapy.


Assuntos
Dinaminas/metabolismo , Lipídeos/análise , Miócitos Cardíacos/metabolismo , Acetilação , Animais , Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Morte Celular/genética , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Dinaminas/genética , Feminino , Hiperglicemia/etiologia , Hiperglicemia/metabolismo , Hiperinsulinismo/etiologia , Hiperinsulinismo/metabolismo , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Hipertensão/etiologia , Hipertensão/metabolismo , Macaca mulatta , Masculino , Camundongos Endogâmicos C57BL , Mutação , Miócitos Cardíacos/patologia , Obesidade/etiologia , Obesidade/metabolismo , Ratos Sprague-Dawley
6.
Circulation ; 141(3): 199-216, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31906693

RESUMO

BACKGROUND: Orai1 is a critical ion channel subunit, best recognized as a mediator of store-operated Ca2+ entry (SOCE) in nonexcitable cells. SOCE has recently emerged as a key contributor of cardiac hypertrophy and heart failure but the relevance of Orai1 is still unclear. METHODS: To test the role of these Orai1 channels in the cardiac pathophysiology, a transgenic mouse was generated with cardiomyocyte-specific expression of an ion pore-disruptive Orai1R91W mutant (C-dnO1). Synthetic chemistry and channel screening strategies were used to develop 4-(2,5-dimethoxyphenyl)-N-[(pyridin-4-yl)methyl]aniline (hereafter referred to as JPIII), a small-molecule Orai1 channel inhibitor suitable for in vivo delivery. RESULTS: Adult mice subjected to transverse aortic constriction (TAC) developed cardiac hypertrophy and reduced ventricular function associated with increased Orai1 expression and Orai1-dependent SOCE (assessed by Mn2+ influx). C-dnO1 mice displayed normal cardiac electromechanical function and cellular excitation-contraction coupling despite reduced Orai1-dependent SOCE. Five weeks after TAC, C-dnO1 mice were protected from systolic dysfunction (assessed by preserved left ventricular fractional shortening and ejection fraction) even if increased cardiac mass and prohypertrophic markers induction were observed. This is correlated with a protection from TAC-induced cellular Ca2+ signaling alterations (increased SOCE, decreased [Ca2+]i transients amplitude and decay rate, lower SR Ca2+ load and depressed cellular contractility) and SERCA2a downregulation in ventricular cardiomyocytes from C-dnO1 mice, associated with blunted Pyk2 signaling. There was also less fibrosis in heart sections from C-dnO1 mice after TAC. Moreover, 3 weeks treatment with JPIII following 5 weeks of TAC confirmed the translational relevance of an Orai1 inhibition strategy during hypertrophic insult. CONCLUSIONS: The findings suggest a key role of cardiac Orai1 channels and the potential for Orai1 channel inhibitors as inotropic therapies for maintaining contractility reserve after hypertrophic stress.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Cardiomegalia/metabolismo , Miócitos Cardíacos/metabolismo , Proteína ORAI1/antagonistas & inibidores , Proteína ORAI1/metabolismo , Função Ventricular Esquerda , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Quinase 2 de Adesão Focal/genética , Quinase 2 de Adesão Focal/metabolismo , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/patologia , Proteína ORAI1/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
7.
Biochem Biophys Res Commun ; 523(4): 867-873, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31955888

RESUMO

Inflammation is centrally involved in the development of cardiac hypertrophy and the processes of remodelling. The complement system and Toll-like receptor (TLR) family, two upstream arms of the innate immune system, have previously been reported to be involved in cardiac remodelling. However, the role of complement component 3 (C3), TLR co-receptor CD14 and the synergy between them have not been addressed during pressure overload-induced cardiac remodelling. Here, we examined angiotensin II-induced cardiac hypertrophy and remodelling for 7 days in male C57Bl/6 J mice deficient in C3, CD14, or both (C3CD14), and WT controls. Angiotensin II infusion induced a mild concentric hypertrophic phenotype in WT mice with increased left ventricle weight, wall thicknesses and reduced ventricular internal diameter, associated with increased cardiac fibrosis. However, there were no differences between WT mice and mice deficient for C3, CD14 or C3CD14, as systolic blood pressure, cardiac function and structure and levels of fibrosis were comparable between WT mice and the three other genotypes. C5a did not change in angiotensin II treated mice, whereas Mac2 levels were increased in angiotensin II treated mice, but did not differ between genotypes. The inflammatory IL-6 response was comparable between WT and C3 deficient mice, however, it was decreased in CD14 and C3CD14 deficient mice. We conclude that deficiency in C3, CD14 or C3CD14 had no effect on cardiac remodelling following angiotensin II-induced pressure overload. This suggests that C3 and CD14 are not involved in angiotensin II-induced adverse cardiac remodelling.


Assuntos
Angiotensina II/farmacologia , Complemento C3/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Receptores Toll-Like/metabolismo , Remodelação Ventricular/efeitos dos fármacos , Animais , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/sangue , Cardiomegalia/genética , Fibrose , Hipertrofia , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Tamanho do Órgão/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sístole/efeitos dos fármacos
8.
Artigo em Inglês | MEDLINE | ID: mdl-31977249

RESUMO

Tandem pore domain acid-sensitive K+ (TASK) channels are present in cardiac tissue; however, their contribution to cardiac pathophysiology is not well understood. Here, we investigate the role of TASK-1 and TASK-3 in the pathogenesis of cardiac dysfunction using both human tissue and mouse models of genetic TASK channel loss of function. Compared with normal human cardiac tissue, TASK-1 gene expression is reduced in association with either cardiac hypertrophy alone or combined cardiac hypertrophy and heart failure. In a pressure overload cardiomyopathy model, TASK-1 global knockout (TASK-1 KO) mice have both reduced cardiac hypertrophy and preserved cardiac function compared with wild-type mice. In contrast to the TASK-1 KO mouse pressure overload response, TASK-3 global knockout (TASK-3 KO) mice develop cardiac hypertrophy and a delayed onset of cardiac dysfunction compared with wild-type mice. The cardioprotective effects observed in TASK-1 KO mice are associated with pressure overload-induced augmentation of AKT phosphorylation and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) expression, with consequent augmentation of cardiac energetics and fatty acid oxidation. The protective effects of TASK-1 loss of function are associated with an enhancement of physiologic hypertrophic signaling and preserved metabolic functions. These findings may provide a rationale for TASK-1 channel inhibition in the treatment of cardiac dysfunction.NEW & NOTEWORTHY The role of tandem pore domain acid-sensitive K+ (TASK) channels in cardiac function is not well understood. This study demonstrates that TASK channel gene expression is associated with the onset of human cardiac hypertrophy and heart failure. TASK-1 and TASK-3 strongly affect the development of pressure overload cardiomyopathies in genetic models of TASK-1 and TASK-3 loss of function. The effects of TASK-1 loss of function were associated with enhanced AKT phosphorylation and expression of peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) transcription factor. These data suggest that TASK channels influence the development of cardiac hypertrophy and dysfunction in response to injury.


Assuntos
Cardiomegalia/metabolismo , Cardiomiopatias/metabolismo , Miocárdio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Canais de Potássio/metabolismo , Remodelação Ventricular/fisiologia , Animais , Cardiomegalia/genética , Cardiomiopatias/genética , Humanos , Camundongos , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosforilação , Canais de Potássio/genética , Canais de Potássio de Domínios Poros em Tandem/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
9.
Am J Physiol Cell Physiol ; 318(1): C94-C102, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31618079

RESUMO

Matrix metalloproteinases (MMP) are important for cardiac remodeling. Recently, microRNA (miR)-451a has been found to inhibit the expression of both MMP-2 and MMP-9 in human malignancies, but its role in cardiomyocytes has not been explored. We hypothesized that miR-451a modulates MMP-2 and MMP-9 levels in human cardiomyocytes. The role of miR-451a on regulation of MMP-2 and MMP-9 was evaluated in two separate pathological models using Cor.4U human inducible pluripotent stem cell-derived cardiomyocytes (hiPS-CMs): 1) endothelin-1 (ET-1), and 2) 48-h hypoxia (1% O2). Both models were transfected with synthetic miR-451a mimics or scramble control. Expression of both mRNA and miR was determined by quantitative real-time polymerase chain reaction and protein activity by (MMP-2/9) activity assay. Bioinformatic analyses were performed using Targetscan 7.1 and STRING 10.5. hiPS-CMs stimulated by hypoxia increased both MMP-2 and MMP-9 expression levels compared with normoxia (P < 0.05), whereas ET-1 stimulation only increased the MMP-9 level compared with vehicle controls (P < 0.05). miR-451a mimics prevented the increase of MMP-2 and MMP-9 expression in both models. Protein activity of MMP-2 and MMP-9 was confirmed to be lower following treatment with miR-451a mimic compared with scramble-controls. Six of 28 predicted gene transcripts of miR-451a were linked to MMP-2 and MMP-9; Macrophage migration inhibitory factor (MIF) was the only predicted target of miR-451a that was increased by ET-1 and hypoxia and reduced following miR-451a mimic transfection. miR-451a prevent the increase of MMP-2 and MMP-9 in human cardiomyocytes during pathological stress. The modulation by miR-451a on MMP-2 and MMP-9 is caused by MIF.


Assuntos
Cardiomegalia/enzimologia , Células-Tronco Pluripotentes Induzidas/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/metabolismo , Miócitos Cardíacos/enzimologia , Cardiomegalia/genética , Cardiomegalia/patologia , Diferenciação Celular , Hipóxia Celular , Linhagem Celular , Endotelina-1/toxicidade , Ativação Enzimática , Regulação Enzimológica da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/patologia , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , MicroRNAs/genética , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Transdução de Sinais
10.
Cell Mol Life Sci ; 77(5): 903-918, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31312877

RESUMO

MicroRNAs (miRs) contribute to different aspects of cardiovascular pathology, among others cardiac hypertrophy and atrial fibrillation. The aim of our study was to evaluate the impact of miR-221/222 on cardiac electrical remodeling. Cardiac miR expression was analyzed in a mouse model with altered electrocardiography parameters and severe heart hypertrophy. Next generation sequencing revealed 14 differentially expressed miRs in hypertrophic hearts, with miR-221 and -222 being the strongest regulated miR-cluster. This increase was restricted to cardiomyocytes and not observed in cardiac fibroblasts. Additionally, we evaluated the change of miR-221/222 in vivo in two models of pharmacologically induced heart hypertrophy (angiotensin II, isoprenaline), thereby demonstrating a stimulus-induced increase in miR-221/222 in vivo by angiotensin II but not by isoprenaline. Whole transcriptome analysis by RNA-seq and qRT-PCR validation revealed an enriched number of downregulated mRNAs coding for proteins located in the T-tubule, which are also predicted targets for miR-221/222. Among those, mRNAs were the L-type Ca2+ channel subunits as well as potassium channel subunits. We confirmed that both miRs target the 3'-untranslated regions of Cacna1c and Kcnj5. Furthermore, enhanced expression of these miRs reduced L-type Ca2+ channel and Kcnj5 channel abundance and function, which was analyzed by whole-cell patch clamp recordings or Western blot and flux measurements, respectively. miR-221 and -222 contribute to the regulation of L-type Ca2+ channels as well as Kcnj5 channels and, therefore, potentially contribute to disturbed cardiac excitation generation and propagation. Future studies will have to evaluate the pathophysiological and clinical relevance of aberrant miR-221/222 expression for electrical remodeling.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , MicroRNAs/genética , Canais de Potássio/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Cardiomegalia/genética , Cardiomegalia/patologia , Linhagem Celular , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Camundongos , Camundongos Knockout , Miócitos Cardíacos/citologia , Técnicas de Patch-Clamp , Canais de Potássio/genética
11.
Hypertension ; 75(1): 98-108, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31735083

RESUMO

Sirt (Sirtuin) 7, the most recently identified mammalian sirtuin, has been shown to contribute to appropriate wound healing processes after acute cardiovascular insult. However, its role in the development of cardiac remodeling after pressure overload is unclear. Cardiomyocyte-specific Sirt7-knockout and control mice were subjected to pressure overload induced by transverse aortic constriction. Cardiac hypertrophy and functions were then examined in these mice. Sirt7 protein expression was increased in myocardial tissue after pressure overload. Transverse aortic constriction-induced increases in heart weight/tibial length were significantly augmented in cardiomyocyte-specific Sirt7-knockout mice compared with those of control mice. Histological analysis showed that the cardiomyocyte cross-sectional area and fibrosis area were significantly larger in cardiomyocyte-specific Sirt7-deficient mice. Cardiac contractile functions were markedly decreased in cardiomyocyte-specific Sirt7-deficient mice. Mechanistically, we found that Sirt7 interacted directly with GATA4 and that the exacerbation of phenylephrine-induced cardiac hypertrophy by Sirt7 knockdown was decreased by GATA4 knockdown. Sirt7 deacetylated GATA4 in cardiomyocytes and regulated its transcriptional activity. Interestingly, we demonstrated that treatment with nicotinamide mononucleotide, a known key NAD+ intermediate, ameliorated agonist-induced cardiac hypertrophies in a Sirt7-dependent manner in vitro. Sirt7 deficiency in cardiomyocytes promotes cardiomyocyte hypertrophy in response to pressure overload. Sirt7 exerts its antihypertrophic effect by interacting with and promoting deacetylation of GATA4.


Assuntos
Cardiomegalia/metabolismo , Fator de Transcrição GATA4/metabolismo , Miócitos Cardíacos/metabolismo , Sirtuínas/metabolismo , Acetilação , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Fator de Transcrição GATA4/genética , Camundongos , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/patologia , Sirtuínas/genética
12.
Hypertension ; 75(1): 79-90, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31735087

RESUMO

Transcribed ultraconserved regions (T-UCRs) are a novel class of long noncoding RNAs transcribed from UCRs, which exhibit 100% DNA sequence conservation among humans, mice, and rats. However, whether T-UCRs regulate cardiac hypertrophy remains unclear. We aimed to explore the effects of T-UCRs on cardiac hypertrophy. First, we performed long noncoding RNA microarray analysis on hearts of mice subjected to sham surgery or aortic banding and found that the T-UCR uc.323 was decreased significantly in mice with aortic banding-induced cardiac hypertrophy. In vitro loss- and gain-of-function experiments demonstrated that uc.323 protected cardiomyocytes against hypertrophy induced by phenylephrine. Additionally, we discovered that mammalian target of rapamycin 1 contributed to phenylephrine-induced uc.323 downregulation and uc.323-mediated cardiomyocyte hypertrophy. We further mapped the possible target genes of uc.323 through global microarray mRNA expression analysis after uc.323 knockdown and found that uc.323 regulated the expression of cardiac hypertrophy-related genes such as CPT1b (Carnitine Palmitoyl transferase 1b). Then, chromatin immunoprecipitation proved that EZH2 (enhancer of zeste homolog 2) bound to the promoter of CPT1b via H3K27me3 (trimethylation of lysine 27 of histone H3) to induce CPT1b downregulation. And overexpression of CPT1b could block uc.323-mediated cardiomyocyte hypertrophy. Finally, we found that uc.323 deficiency induced cardiac hypertrophy. Our results reveal that uc.323 is a conserved T-UCR that inhibits cardiac hypertrophy, potentially by regulating the transcription of CPT1b via interaction with EZH2.


Assuntos
Cardiomegalia/genética , Carnitina O-Palmitoiltransferase/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Miocárdio/metabolismo , RNA Longo não Codificante/genética , Animais , Cardiomegalia/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Sequência Conservada , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/metabolismo , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Transcrição Genética
13.
Am J Med Genet C Semin Med Genet ; 181(4): 658-681, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31828977

RESUMO

Cantú syndrome (CS), first described in 1982, is caused by pathogenic variants in ABCC9 and KCNJ8, which encode the regulatory and pore forming subunits of ATP-sensitive potassium (KATP ) channels, respectively. Multiple case reports of affected individuals have described the various clinical features of CS, but systematic studies are lacking. To define the effects of genetic variants on CS phenotypes and clinical outcomes, we have developed a standardized REDCap-based registry for CS. We report phenotypic features and associated genotypes on 74 CS subjects, with confirmed ABCC9 variants in 72 of the individuals. Hypertrichosis and a characteristic facial appearance are present in all individuals. Polyhydramnios during fetal life, hyperflexibility, edema, patent ductus arteriosus (PDA), cardiomegaly, dilated aortic root, vascular tortuosity of cerebral arteries, and migraine headaches are common features, although even with this large group of subjects, there is incomplete penetrance of CS-associated features, without clear correlation to genotype.


Assuntos
Cardiomegalia/epidemiologia , Hipertricose/epidemiologia , Osteocondrodisplasias/epidemiologia , Sistema de Registros , Adolescente , Adulto , Cardiomegalia/genética , Criança , Facies , Feminino , Humanos , Hipertricose/genética , Masculino , Osteocondrodisplasias/genética , Fenótipo , Adulto Jovem
14.
Biol Sex Differ ; 10(1): 59, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842996

RESUMO

BACKGROUND: Over a third of reproductive-age women in the USA are obese, and the prevalence of cardiovascular disease (CVD) is rising in premenopausal women. Cardiac hypertrophy is an independent predictor of CVD. In contrast to pregnancy, where transiently increased left ventricular (LV) mass is not associated with cardiac damage, obesity-mediated cardiac hypertrophy is pathological. There is a paucity of data describing the effect of obesity during pregnancy on maternal cardiovascular health. The purpose of this study was to determine the long-term effect of obesity during pregnancy on cardiac function and structure in mice. METHODS: Female C57BL/6 J mice were fed a high-fat (HF) or a low-fat (LF) diet for 20 weeks. After 4 weeks, LF- and HF-fed female mice were either crossed with males to become pregnant or remained non-pregnant controls. Following delivery, pups were euthanized, and females maintained on respective diets. After 20 weeks of diet feeding, cardiac function was quantified by echocardiography, and plasma leptin and adiponectin concentrations quantified in LF- and HF-fed postpartum and nulliparous females. mRNA abundance of genes regulating cardiac hypertrophy and remodeling was quantified from left ventricles using the NanoString nCounter Analysis System. Cardiac fibrosis was assessed from picrosirius red staining of left ventricles. RESULTS: HF-fed postpartum mice had markedly greater weight gain and fat mass expansion with obesity, associated with significantly increased LV mass, cardiac output, and stroke volume compared with HF-fed nulliparous mice. Plasma leptin, but not adiponectin, concentrations were correlated with LV mass in HF-fed females. HF feeding increased LV posterior wall thickness; however, LV chamber diameter was only increased in HF-fed postpartum females. Despite the marked increase in LV mass in HF-fed postpartum mice, mRNA abundance of genes regulating fibrosis and interstitial collagen content was similar between HF-fed nulliparous and postpartum mice. In contrast, only HF-fed postpartum mice exhibited altered expression of genes regulating the extracellular matrix. CONCLUSIONS: These results suggest that the combined effects of pregnancy and obesity augment cardiac hypertrophy and promote remodeling. The rising prevalence of CVD in premenopausal women may be attributed to an increased prevalence of women entering pregnancy with an overweight or obese BMI.


Assuntos
Cardiomegalia/patologia , Ventrículos do Coração/patologia , Obesidade/patologia , Adiponectina/sangue , Animais , Cardiomegalia/sangue , Cardiomegalia/genética , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Feminino , Leptina/sangue , Camundongos Endogâmicos C57BL , Obesidade/sangue , Obesidade/genética , Gravidez , Transcriptoma
15.
Med Sci Monit ; 25: 9609-9617, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31840653

RESUMO

BACKGROUND Cardiac myocyte hypertrophy results from clinical conditions that include hypertension and valvular heart disease, and can result in heart failure. This study aimed to investigate the expression and role of the long noncoding RNA FTX (lnc-FTX), an X-inactive-specific transcript (XIST) regulator transcribed from the X chromosome, in hypertrophy of neonatal mouse cardiac myocytes induced by angiotensin II (Ang II) in vitro. MATERIAL AND METHODS Cardiac myocytes were isolated from neonatal mice and cultured with and without Ang II. Immunofluorescence, with localization of an antibody to alpha-smooth muscle actin (alpha-SMA), was used to identify the neonatal mouse cardiac myocytes. Quantitative real-time polymerase chain reaction (qRT-PCR) measured gene expression levels. The cell counting kit-8 (CCK-8) assay was used to determine cell viability, and Western blot measured protein expression. StarBase v2.0 bioinformatics software was used for target gene prediction and was confirmed with the luciferase reporter assay. RESULTS The expression of lnc-FTX was reduced in mouse cardiac myocytes treated with Ang II. Overexpression of lnc-FTX reduced cell apoptosis, cardiomyocyte contractility, and the expression of c-Jun, A-type natriuretic peptide (ANP), and B-type natriuretic peptide (BNP) induced by Ang II. The target of lnc-FTX was micro-RNA 22 (miRNA-22). The mechanism of action of lnc-FTX in neonatal mouse cardiac myocytes was through suppression of the PI3K/Akt signaling pathway by promoting the release of PTEN by sponging miRNA-22. CONCLUSIONS The expression of lnc-FTX was associated with reduced hypertrophy of neonatal mouse cardiac myocytes and regulated the PTEN/PI3K/Akt signaling pathway by sponging miRNA-22.


Assuntos
Cardiomegalia/metabolismo , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/metabolismo , Actinas/metabolismo , Angiotensina II/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Cardiomegalia/genética , Cardiomegalia/patologia , Células Cultivadas , Insuficiência Cardíaca/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Miocárdio/metabolismo , Miócitos Cardíacos/patologia , RNA Longo não Codificante/genética , Transdução de Sinais
16.
Dis Markers ; 2019: 5058313, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772688

RESUMO

Background: Mechanical stress-induced cardiac remodeling that results in heart failure is characterized by transcriptional reprogramming of gene expression. However, a systematic study of genomic changes involved in this process has not been performed to date. To investigate the genomic changes and underlying mechanism of cardiac remodeling, we collected and analyzed DNA microarray data for murine transverse aortic constriction (TAC) and human aortic stenosis (AS) from the Gene Expression Omnibus database and the European Bioinformatics Institute. Methods and Results: The differential expression genes (DEGs) across the datasets were merged. The Venn diagrams showed that the number of intersections for early and late cardiac remodeling was 74 and 16, respectively. Gene ontology and protein-protein interaction network analysis showed that metabolic changes, cell differentiation and growth, cell cycling, and collagen fibril organization accounted for a great portion of the DEGs in the TAC model, while in AS patients' immune system signaling and cytokine signaling displayed the most significant changes. The intersections between the TAC model and AS patients were few. Nevertheless, the DEGs of the two species shared some common regulatory transcription factors (TFs), including SP1, CEBPB, PPARG, and NFKB1, when the heart was challenged by applied mechanical stress. Conclusions: This study unravels the complex transcriptome profiles of the heart tissues and highlighting the candidate genes involved in cardiac remodeling induced by mechanical stress may usher in a new era of precision diagnostics and treatment in patients with cardiac remodeling.


Assuntos
Estenose da Valva Aórtica/genética , Cardiomegalia/genética , Fatores de Transcrição/genética , Animais , Aorta/cirurgia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Humanos , Camundongos , Mapas de Interação de Proteínas/genética , Estresse Mecânico , Remodelação Ventricular/genética
17.
Chin J Nat Med ; 17(10): 746-755, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31703755

RESUMO

To investigate the effect of Yiqi Wenyang (YQWY) decoction on reversing cardiac hypertrophy induced by the transverse aortic constriction (TAC). Wistar rats aged 7-8 weeks were subjected to TAC surgery and then randomly divided into 4 groups (n = 5/group): Sham group, TAC group, low-dose group and high dose group. After 16-week intragastric administration of YQWY decoction, the effect of YQWY decoction on alleviating cardiomyocyte hypertrophy was examined by transthoracic echocardiography (TTE), hematoxylin/eosin (HE), wheat germ agglutinin (WGA) staining, enzyme linked immunosorbent assay (ELISA), Western blot (WB), immunohistochemistry (IHC) and immunofluorescence (IF), respectively. The results showed significant differences in left ventricle volume-diastole/systole (LV Vol d/s), N-terminal pro-B-type brain natriuretic peptide (NT-proBNP) (P < 0.01), Ejection Fraction (EF), LV mass and fractional shortening (FS) (P < 0.05) between YQWY-treated group and TAC group. HE and WGA staining showed that treatment with YQWY decoction dramatically prevented TAC-induced cardiomycyte hypertrophy. Moreover, the results of WB, IHC and IF indicated that administration of YQWY could suppress the expressions of cardiac hypertrophic markers, which included the atrial natriuretic peptide (ANP), BNP and myosin heavy chain 7 (MYH7) (P < 0.05) and inhibit phosphorylation of GATA binding protein 4 (P-GATA4) (P < 0.05), phosphorylation of extracellular signal-regulated kinase (P-ERK) (P < 0.05), phosphorylation of P38 mitogen activated protein kinase (P-P38) (P < 0.05) and phosphorylation of c-Jun N-terminal kinase (P-JNK) (P < 0.05). Thus, we concluded that YQWY decoction suppressed cardiomyocyte hypertrophy and reversed the impaired heart function, and the curative effects of YQWY decoction were associated with the decreased phosphorylation of GATA4 and mitogen activated protein kinases (MAPKs), as well as the reduced expression of the downstream targets of GATA4, including ANP, BNP, and MYH7.


Assuntos
Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Fator de Transcrição GATA4/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Aorta/cirurgia , Cardiomegalia/genética , Fator de Transcrição GATA4/genética , Humanos , Masculino , Proteínas Quinases Ativadas por Mitógeno/genética , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosforilação , Ratos , Ratos Wistar
18.
J Pharm Pharmacol ; 71(12): 1822-1831, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31612504

RESUMO

OBJECTIVES: This study aimed to evaluate berberine (BBR) effects on myocardial hypertrophy (MH) and associated mechanisms. METHODS: BBR effects on MH were evaluated in rats with constriction of abdominal aorta (CAA). qRT-PCR assay was used to measure MH-related genes, long non-coding RNAs (lncRNAs) and autophagy-related genes expressions. Western blot was performed to detect autophagy markers expression. Filamentous actin and phalloidin expressions were detected using immunofluorescence assay. KEY FINDINGS: BBR significantly attenuated CAA-induced MH and cardiomyocyte enlargement. CAA upregulated ß myosin heavy chain and atrial natriuretic peptide expressions in heart tissues, which was attenuated by BBR. BBR suppressed myocardial infarction associated transcript (MIAT) expression in rats with CAA. p62 mRNA expression was upregulated and beclin1 and autophagy related 5 were downregulated in CAA versus control groups. The effects were abolished by BBR. In vitro studies showed that BBR ameliorated angiotensin II-induced MH and attenuated Ang II-induced MIAT expression in H9C2 cells. Expressions of phosphorylated mTOR, phosphorylated AMPK and LC3 were upregulated in H9C2 cells after Ang II stimulation, and the effects were abolished by BBR. CONCLUSIONS: BBR exerted beneficial effects on MH induced by CCA, and the mechanisms were associated with decreased MIAT expression and enhanced autophagy.


Assuntos
Berberina/farmacologia , Cardiomegalia/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , RNA Longo não Codificante/genética , Animais , Autofagia/efeitos dos fármacos , Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Masculino , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
19.
Nucleic Acids Res ; 47(20): 10771-10787, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31598705

RESUMO

Alternative polyadenylation (APA)-mediated 3'-untranslated region (UTR) shortening is known to increase protein expression due to the loss of miRNA regulatory sites. Yet, mRNAs with longer 3'-UTR also show enhanced protein expression. Here, we identify a mechanism by which longer transcripts generated by the distal-most APA site leads to increased protein expression compared to the shorter transcripts and the longer transcripts are positioned to regulate heart failure (HF). A Star-PAP target gene, NQO1 has three poly(A) sites (PA-sites) at the terminal exon on the pre-mRNA. Star-PAP selects the distal-most site that results in the expression of the longest isoform. We show that the NQO1 distal-specific mRNA isoform accounts for the majority of cellular NQO1 protein. Star-PAP control of the distal-specific isoform is stimulated by oxidative stress and the toxin dioxin. The longest NQO1 transcript has increased poly(A) tail (PA-tail) length that accounts for the difference in translation potentials of the three NQO1 isoforms. This mechanism is involved in the regulation of cardiac hypertrophy (CH), an antecedent condition to HF where NQO1 downregulation stems from the loss of the distal-specific transcript. The loss of NQO1 during hypertrophy was rescued by ectopic expression of the distal- but not the proximal- or middle-specific NQO1 mRNA isoforms in the presence of Star-PAP expression, and reverses molecular events of hypertrophy in cardiomyocytes.


Assuntos
Cardiomegalia/metabolismo , Poli A/metabolismo , Poliadenilação , Polinucleotídeo Adenililtransferase/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Cardiomegalia/genética , Linhagem Celular , Humanos , Masculino , Camundongos , Modelos Biológicos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos Wistar
20.
Nat Commun ; 10(1): 4457, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575858

RESUMO

Mutations in genes encoding KATP channel subunits have been reported for pancreatic disorders and Cantú syndrome. Here, we report a syndrome in six patients from two families with a consistent phenotype of mild intellectual disability, similar facies, myopathy, and cerebral white matter hyperintensities, with cardiac systolic dysfunction present in the two oldest patients. Patients are homozygous for a splice-site mutation in ABCC9 (c.1320 + 1 G > A), which encodes the sulfonylurea receptor 2 (SUR2) subunit of KATP channels. This mutation results in an in-frame deletion of exon 8, which results in non-functional KATP channels in recombinant assays. SUR2 loss-of-function causes fatigability and cardiac dysfunction in mice, and reduced activity, cardiac dysfunction and ventricular enlargement in zebrafish. We term this channelopathy resulting from loss-of-function of SUR2-containing KATP channels ABCC9-related Intellectual disability Myopathy Syndrome (AIMS). The phenotype differs from Cantú syndrome, which is caused by gain-of-function ABCC9 mutations, reflecting the opposing consequences of KATP loss- versus gain-of-function.


Assuntos
Trifosfato de Adenosina/metabolismo , Canalopatias/metabolismo , Predisposição Genética para Doença/genética , Deficiência Intelectual/metabolismo , Doenças Musculares/metabolismo , Mutação , Receptores Sulfonilureia/genética , Receptores Sulfonilureia/metabolismo , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Linhagem Celular , Criança , Modelos Animais de Doenças , Facies , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/genética , Coração , Cardiopatias/genética , Cardiopatias/metabolismo , Homozigoto , Humanos , Hipertricose/genética , Hipertricose/metabolismo , Deficiência Intelectual/parasitologia , Masculino , Complexo Mediador/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Doenças Musculares/genética , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/fisiopatologia , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Linhagem , Fenótipo , Rubídio , Sequenciamento Completo do Genoma , Adulto Jovem , Peixe-Zebra
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