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1.
Circulation ; 142(2): 161-174, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32264695

RESUMO

BACKGROUND: The cyclic AMP (adenosine monophosphate; cAMP)-hydrolyzing protein PDE4B (phosphodiesterase 4B) is a key negative regulator of cardiac ß-adrenergic receptor stimulation. PDE4B deficiency leads to abnormal Ca2+ handling and PDE4B is decreased in pressure overload hypertrophy, suggesting that increasing PDE4B in the heart is beneficial in heart failure. METHODS: We measured PDE4B expression in human cardiac tissues and developed 2 transgenic mouse lines with cardiomyocyte-specific overexpression of PDE4B and an adeno-associated virus serotype 9 encoding PDE4B. Myocardial structure and function were evaluated by echocardiography, ECG, and in Langendorff-perfused hearts. Also, cAMP and PKA (cAMP dependent protein kinase) activity were monitored by Förster resonance energy transfer, L-type Ca2+ current by whole-cell patch-clamp, and cardiomyocyte shortening and Ca2+ transients with an Ionoptix system. Heart failure was induced by 2 weeks infusion of isoproterenol or transverse aortic constriction. Cardiac remodeling was evaluated by serial echocardiography, morphometric analysis, and histology. RESULTS: PDE4B protein was decreased in human failing hearts. The first PDE4B-transgenic mouse line (TG15) had a ≈15-fold increase in cardiac cAMP-PDE activity and a ≈30% decrease in cAMP content and fractional shortening associated with a mild cardiac hypertrophy that resorbed with age. Basal ex vivo myocardial function was unchanged, but ß-adrenergic receptor stimulation of cardiac inotropy, cAMP, PKA, L-type Ca2+ current, Ca2+ transients, and cell contraction were blunted. Endurance capacity and life expectancy were normal. Moreover, these mice were protected from systolic dysfunction, hypertrophy, lung congestion, and fibrosis induced by chronic isoproterenol treatment. In the second PDE4B-transgenic mouse line (TG50), markedly higher PDE4B overexpression, resulting in a ≈50-fold increase in cardiac cAMP-PDE activity caused a ≈50% decrease in fractional shortening, hypertrophy, dilatation, and premature death. In contrast, mice injected with adeno-associated virus serotype 9 encoding PDE4B (1012 viral particles/mouse) had a ≈50% increase in cardiac cAMP-PDE activity, which did not modify basal cardiac function but efficiently prevented systolic dysfunction, apoptosis, and fibrosis, while attenuating hypertrophy induced by chronic isoproterenol infusion. Similarly, adeno-associated virus serotype 9 encoding PDE4B slowed contractile deterioration, attenuated hypertrophy and lung congestion, and prevented apoptosis and fibrotic remodeling in transverse aortic constriction. CONCLUSIONS: Our results indicate that a moderate increase in PDE4B is cardioprotective and suggest that cardiac gene therapy with PDE4B might constitute a new promising approach to treat heart failure.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Expressão Gênica , Insuficiência Cardíaca/etiologia , Miocárdio/metabolismo , Remodelação Ventricular/genética , Agonistas Adrenérgicos beta/farmacologia , Animais , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Terapia Genética , Vetores Genéticos/genética , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Testes de Função Cardíaca , Humanos , Isoproterenol/farmacologia , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenótipo , Receptores Adrenérgicos beta/metabolismo , Transdução Genética , Remodelação Ventricular/efeitos dos fármacos
2.
J Mol Cell Cardiol ; 133: 57-66, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31158360

RESUMO

AIMS: Cyclic AMP phosphodiesterases (PDEs) are important modulators of the cardiac response to ß-adrenergic receptor (ß-AR) stimulation. PDE3 is classically considered as the major cardiac PDE in large mammals and human, while PDE4 is preponderant in rodents. However, it remains unclear whether PDE4 also plays a functional role in large mammals. Our purpose was to understand the role of PDE4 in cAMP hydrolysis and excitation-contraction coupling (ECC) in the pig heart, a relevant pre-clinical model. METHODS AND RESULTS: Real-time cAMP variations were measured in isolated adult pig right ventricular myocytes (APVMs) using a Förster resonance energy transfer (FRET) biosensor. ECC was investigated in APVMs loaded with Fura-2 and paced at 1 Hz allowing simultaneous measurement of intracellular Ca2+ and sarcomere shortening. The expression of the different PDE4 subfamilies was assessed by Western blot in pig right ventricles and APVMs. Similarly to PDE3 inhibition with cilostamide (Cil), PDE4 inhibition with Ro 20-1724 (Ro) increased cAMP levels and inotropy under basal conditions. PDE4 inhibition enhanced the effects of the non-selective ß-AR agonist isoprenaline (Iso) and the effects of Cil, and increased spontaneous diastolic Ca2+ waves (SCWs) in these conditions. PDE3A, PDE4A, PDE4B and PDE4D subfamilies are expressed in pig ventricles. In APVMs isolated from a porcine model of repaired tetralogy of Fallot which leads to right ventricular failure, PDE4 inhibition also exerts inotropic and pro-arrhythmic effects. CONCLUSIONS: Our results show that PDE4 controls ECC in APVMs and suggest that PDE4 inhibitors exert inotropic and pro-arrhythmic effects upon PDE3 inhibition or ß-AR stimulation in our pre-clinical model. Thus, PDE4 inhibitors should be used with caution in clinics as they may lead to arrhythmogenic events upon stress.


Assuntos
AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Acoplamento Excitação-Contração/genética , Miócitos Cardíacos/fisiologia , Potenciais de Ação/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Família Multigênica , Miócitos Cardíacos/efeitos dos fármacos , Inibidores da Fosfodiesterase 3/farmacologia , Inibidores da Fosfodiesterase 4/farmacologia , Receptores Adrenérgicos beta/metabolismo , Suínos
3.
Eur Heart J ; 39(20): 1794-1798, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29244074

RESUMO

Aims: Heart failure (HF) is accompanied by major neuroendocrine changes including the activation of the natriuretic peptide (NP) pathway. Using the unique model of patients undergoing implantation of the CARMAT total artificial heart and investigating regional differences in soluble neprilysin (sNEP) in patients with reduced or preserved systolic function, we studied the regulation of the NP pathway in HF. Methods and results: Venous blood samples from two patients undergoing replacement of the failing ventricles with a total artificial heart were collected before implantation and weekly thereafter until post-operative week 6. The ventricular removal was associated with an immediate drop in circulating NPs, a nearly total disappearance of circulating glycosylated proBNP and furin activity and a marked decrease in sNEP. From post-operative week 1 onwards, NP concentrations remained overall unchanged. In contrast, partial recoveries in glycosylated proBNP, furin activity, and sNEP were observed. Furthermore, while in patients with preserved systolic function (n = 6), sNEP concentrations in the coronary sinus and systemic vessels were similar (all P > 0.05), in patients with reduced left-ventricular systolic function, sNEP concentration, and activity were ∼three-fold higher in coronary sinus compared to systemic vessels (n = 21, all P < 0.0001), while the trans-pulmonary gradient was neutral (n = 5, P = 1.0). Conclusion: The heart plays a pivotal role as a regulator of the endocrine response in systolic dysfunction, not only by directly releasing NPs but also by contributing to circulating sNEP, which in turn determines the bioavailability of other numerous vasoactive peptides.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Coração/fisiopatologia , Peptídeos Natriuréticos/fisiologia , Neprilisina/fisiologia , Idoso , Biomarcadores/sangue , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/cirurgia , Coração Artificial , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Neprilisina/sangue , Neprilisina/genética , Fragmentos de Peptídeos/sangue , Período Pós-Operatório , RNA Mensageiro/genética , Transdução de Sinais/fisiologia , Sístole/fisiologia
4.
J Mol Cell Cardiol ; 119: 75-86, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29723491

RESUMO

QSOX1, a sulfhydryl oxidase, was shown to be upregulated in the heart upon acute heart failure (AHF). The aim of the study was to unravel QSOX1 roles during AHF. We generated and characterized mice with QSOX1 gene deletion. The QSOX1-/- mice were viable but adult male exhibited a silent dilated cardiomyopathy. The QSOX1-/- hearts were characterized by low protein SERCA2a levels associated with a calcium homeostasis alteration, high levels of the endoplasmic reticulum (ER) chaperone proteins Grp78/Bip, and of the ER apoptosis sensor CHOP, indicating a chronic unfolded protein response (UPR). Importantly the QSOX1invalidation led to overexpression of two ER oxidases, ERO1-α and PRDX4. Acute stress was induced by isoproterenol injection (ISO, 300 mg/kg/12 h) for 2 days. In both groups, the PERK UPR pathway was transiently activated 6 h after the first ISO injection as indicated by eIF2 phosphorylation. By day-3 after the onset of stress, both WT and QSOX1-/- mice exhibited AHF profile but while high cardiac QSOX1 level was induced in WT hearts, ERO1-α and PRDX4 levels drop down in QSOX1-/-. At that time, QSOX1-/- hearts exhibited an enhanced inflammation (CD68+ cells and Galectin-3 expression) and oxidative stress (DHE staining and oxyblot) when compared to WT ones. In conclusion, the lack of QSOX1 promotes the upregulation of two ER oxidases ERO1α and PRDX4 that likely rescues oxidative protein folding in the hearts. However, signs of chronic ER stress remained present and were associated with a dilated cardiomyopathy. The superimposition of acute stress allowed us to propose that QSOX1 participate to the early response to cardiac stress but not to immediate UPR response. Taken altogether, the data indicated that QSOX1 is required 1) for a proper protein folding in the endo/sarcoplasmic reticulum (ER/SR) and 2) for resolution and protective response during acute stress.


Assuntos
Cardiomiopatia Dilatada/genética , Insuficiência Cardíaca/genética , Inflamação/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Animais , Apoptose/genética , Cálcio/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Deleção de Genes , Regulação da Expressão Gênica/genética , Glicoproteínas/genética , Insuficiência Cardíaca/fisiopatologia , Humanos , Inflamação/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Estresse Oxidativo/genética , Oxirredutases , Peroxirredoxinas/genética , Dobramento de Proteína , Retículo Sarcoplasmático , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Fator de Transcrição CHOP/genética , Resposta a Proteínas não Dobradas/genética
5.
Clin Chem ; 63(1): 386-393, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28062630

RESUMO

BACKGROUND: Soluble CD146 (sCD146), is an endothelial marker with similar diagnostic power as natriuretic peptides in decompensated heart failure (HF). While natriuretic peptides are released by the failing heart, sCD146 may be released by veins in response to stretch induced by systemic congestion in HF. This study investigated the source, effects of vascular stress on release and prognostic properties of sCD146 in HF. METHODS: In a peripheral venous stress study, plasma concentrations of sCD146 and N-terminal probrain natriuretic-peptide (NT-proBNP) were measured in 44 HF patients at baseline and after 90 min of unilateral forearm venous congestion. In addition, sCD146 and NT-proBNP were measured in peripheral vein (PV) and coronary sinus (CS) blood samples of 137 HF patients and the transcardiac gradient was calculated. Those patients were followed for major adverse cardiovascular events (MACE) during 2 years. RESULTS: The induction of venous stress was associated with a pronounced increase in circulating concentrations of sCD146 in the congested arm (+60 µg/L) compared to the control arm (+16 µg/L, P = 0.025), while no difference in NT-proBNP concentrations was seen. In contrast to positive transcardiac gradient for NT-proBNP, median sCD146 concentrations were lower in CS than in PV (396 vs 434, P < 0.001), indicating a predominantly extracardiac source of sCD146. Finally, increased PV concentrations of sCD146 were associated with higher risk of MACE at 2 years. CONCLUSIONS: Soluble CD146 is released from the peripheral vasculature in response to venous stretch and may reflect systemic congestion in chronic HF patients.


Assuntos
Antígeno CD146/sangue , Seio Coronário/patologia , Antebraço/patologia , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Solubilidade
6.
Circ J ; 81(11): 1654-1661, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28552862

RESUMO

BACKGROUND: Concentrations of the anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1) are altered in peripartum cardiomyopathy (PPCM). In this study we investigated changes in the angiogenesis balance in PPCM.Methods and Results:Plasma concentrations of sFlt-1 and the pro-angiogenic placenta growth factor (PlGF) were determined in patients with PPCM during the post-partum phase (n=83), in healthy women at delivery (n=30), and in patients with acute heart failure (AHF; n=65). Women with cardiac failure prepartum or associated with any form of hypertension, including pre-eclampsia, were excluded. Compared with non-pregnant women, in women with AHF and PPCM, median PlGF concentrations were greater (19 [IQR 16-22] and 98 [IQR 78-126] ng/mL, respectively; P<0.001) and the sFlt-1/PlGF ratio was lower (9.8 [6.6-11.3] and 1.2 [0.9-2.8], respectively; P<0.001). The sFlt-1/PlGF ratio was lower in PPCM than in normal deliveries (1.2 [0.9-2.8] vs. 94.8 [68.8-194.1], respectively; P<0.0001). The area under the curve for PlGF (cut-off value: 50ng/mL) and/or the sFlt-1/PlGF ratio (cut-off value: 4) to distinguish PPCM from either normal delivery or AHF was >0.94. Median plasma concentrations of the anti-angiogenic factor relaxin-2 were lower in PPCM and AHF (0.3 [IQR 0.3-1.7] and 0.3 [IQR 0.3-1] ng/mL, respectively) compared with normal deliveries (1,807 [IQR 1,101-4,050] ng/mL; P<0.001). CONCLUSIONS: Plasma of PPCM patients shows imbalanced angiogenesis. High PlGF and/or low sFlt-1/PlGF may be used to diagnose PPCM.


Assuntos
Cardiomiopatias/sangue , Neovascularização Patológica/sangue , Fator de Crescimento Placentário/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Cardiomiopatias/diagnóstico , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Período Periparto , Gravidez
7.
FASEB J ; 28(6): 2430-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24558200

RESUMO

Studies have shown that aldosterone would have angiogenic effects and therefore would be beneficial in the context of cardiovascular diseases. We thus investigated the potential involvement of aldosterone in triggering a cardiac angiogenic response in the context of type-2 diabetes and the molecular pathways involved. Male 3-wk-old aldosterone synthase (AS)-overexpressing mice and their control wild-type (WT) littermates were fed a standard or high-fat, high-sucrose (HFHS) diet. After 6 mo of diet treatment, mice were euthanized, and cardiac samples were assayed by RT-PCR, immunoblotting, and immunohistology. HFHS diet induced type-2 diabetes in WT (WT-D) and AS (AS-D) mice. VEGFa mRNAs decreased in WT-D (-43%, P<0.05 vs. WT) and increased in AS-D mice (+236%, P< 0.01 vs. WT-D). In WT-D mouse hearts, the proapoptotic p38MAPK was activated (P<0.05 vs. WT and AS-D), whereas Akt activity decreased (-64%, P<0.05 vs. WT). The AS mice, which exhibited a cardiac up-regulation of IGF1-R, showed an increase in Akt phosphorylation when diabetes was induced (P<0.05 vs. WT and AS-D). Contrary to WT-D mice, AS-D mouse hearts did not express inflammatory markers and exhibited a normal capillary density (P<0.05 vs. WT-D). To our knowledge, this is the first study providing new insights into the mechanisms whereby aldosterone prevents diabetes-induced cardiac disorders.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Aldosterona/farmacologia , Animais , Glicemia/metabolismo , Citocromo P-450 CYP11B2/biossíntese , Citocromo P-450 CYP11B2/genética , Dieta Hiperlipídica , Coração/efeitos dos fármacos , Hiperaldosteronismo/fisiopatologia , Resistência à Insulina , Masculino , Camundongos , Miocárdio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/biossíntese
8.
Eur Heart J ; 35(48): 3434-41, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25157115

RESUMO

BACKGROUND: Increases in plasma B-type natriuretic peptide (BNP) concentrations in those with acutely decompensated heart failure (ADHF) has been mainly attributed to an increase in NPPB gene transcription. Recently, proBNP glycosylation has emerged as a potential regulatory mechanism in the production of amino-terminal (NT)-proBNP and BNP. The aim of the present study was to investigate proBNP glycosylation, and corin and furin activities in ADHF patients. METHODS AND RESULTS: Plasma levels of proBNP, NT-proBNP, BNP, as well as corin and furin concentration and activity were measured in a large cohort of 683 patients presenting with ADHF (n = 468), non-cardiac dyspnoea (non-ADHF: n = 169) and 46 patients with stable chronic heart failure (CHF); the degree of plasma proBNP glycosylation was assessed in a subset of these patients (ADHF: n = 49, non-ADHF: n = 50, CHF: n = 46). Our results showed a decrease in proBNP glycosylation in ADHF patients that paralleled NT-proBNP overproduction (ρ = -0.62, P < 0.001) but less so to BNP. In addition, we observed an increase in furin activity that is positively related to the plasma levels of proBNP, NT-proBNP and BNP overproduction (all P < 0.001, all ρ > 0.88), and negatively related to the degree of proBNP glycosylation (ρ = -0.62, P < 0.001). CONCLUSION: These comprehensive results provide a paradigm for the post-translational modification of natriuretic peptides in ADHF: as proBNP glycosylation decreases, furin activity increases. This synergistically amplifies the processing of proBNP into BNP and NT-proBNP. CLINICAL TRIAL REGISTRATION: http://clinicaltrials.gov/. Identifier: NCT01374880.


Assuntos
Insuficiência Cardíaca/sangue , Peptídeo Natriurético Encefálico/biossíntese , Fragmentos de Peptídeos/biossíntese , Doença Aguda , Idoso , Estudos de Coortes , Dispneia/etiologia , Feminino , Furina/metabolismo , Glicosilação , Humanos , Masculino , Serina Endopeptidases/metabolismo
9.
Am J Physiol Heart Circ Physiol ; 304(11): H1505-12, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23542920

RESUMO

Peroxisome proliferator-activated receptor (PPAR)-α deletion induces a profound decrease in MnSOD activity, leading to oxidative stress and left ventricular (LV) dysfunction. We tested the hypothesis that treatment of PPAR-α knockout (KO) mice with the SOD mimetic tempol prevents the heart from pathological remodelling and preserves LV function. Twenty PPAR-α KO mice and 20 age-matched wild-type mice were randomly treated for 8 wk with vehicle or tempol in the drinking water. LV contractile parameters were determined both in vivo using echocardiography and ex vivo using papillary muscle mechanics. Translational and posttranslational modifications of myosin heavy chain protein as well as the expression and activity of major antioxidant enzymes were measured. Tempol treatment did not affect LV function in wild-type mice; however, in PPAR-α KO mice, tempol prevented the decrease in LV ejection fraction and restored the contractile parameters of papillary muscle, including maximum shortening velocity, maximum extent of shortening, and total tension. Moreover, compared with untreated PPAR-α KO mice, myosin heavy chain tyrosine nitration and anion superoxide production were markedly reduced in PPAR-α KO mice after treatment. Tempol also significantly increased glutathione peroxidase and glutathione reductase activities (~ 50%) in PPAR-α KO mice. In conclusion, these findings demonstrate that treatment with the SOD mimetic tempol can prevent cardiac dysfunction in PPAR-α KO mice by reducing the oxidation of contractile proteins. In addition, we show that the beneficial effects of tempol in PPAR-α KO mice involve activation of the glutathione peroxidase/glutathione reductase system.


Assuntos
Óxidos N-Cíclicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/fisiologia , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Pressão Arterial/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Western Blotting , Ecocardiografia , Eletroforese em Gel de Poliacrilamida , Glucosefosfato Desidrogenase/metabolismo , Técnicas In Vitro , Isomerismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Contração Miocárdica/efeitos dos fármacos , Miocárdio/enzimologia , Miocárdio/patologia , Cadeias Pesadas de Miosina/metabolismo , PPAR alfa/genética , Músculos Papilares/efeitos dos fármacos , Marcadores de Spin , Superóxido Dismutase/metabolismo , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia
10.
Curr Hypertens Rep ; 15(4): 395-400, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23686824

RESUMO

Cardiac remodeling is a deleterious consequence of arterial hypertension. This remodeling results from cardiac transcriptomic changes induced by mechanical and hormonal factors. Angiotensin II and aldosterone often collaborate in pathological situations to induce hypertrophy of cardiomyocytes, vascular inflammation, perivascular and interstitial fibrosis, and microvascular rarefaction. Experimental models of transgenic mice overexpressing renin in liver, leading to increased plasma angiotensin II and severe hypertension, and mice overexpressing aldosterone-synthase in cardiomyocytes, leading to a doubling of intracardiac aldosterone concentration have shown that cardiac fibrosis in the heart depends on a balance between pro-fibrotic (TGF-ß, galectin-3) and anti-fibrotic (BNP, ANP) factors. Recent studies using cell-specific deletion of the mineralocorticoid receptor indicate that its activation in macrophages is a key step in the development of cardiac fibrosis in the setting of hemodynamic or hormonal challenges. This review focuses on the impact of inappropriate stimulation of aldosterone in the development of cardiac fibrosis.


Assuntos
Aldosterona/metabolismo , Cardiopatias/metabolismo , Hipertensão/metabolismo , Angiotensina II/metabolismo , Animais , Citocromo P-450 CYP11B2/metabolismo , Fibrose/etiologia , Fibrose/metabolismo , Cardiopatias/fisiopatologia , Humanos , Hipertensão/fisiopatologia
11.
Eur Heart J ; 33(18): 2317-24, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22733835

RESUMO

AIMS: Biochemical marker testing has improved the evaluation and management of patients with cardiovascular diseases over the past decade. Natriuretic peptides (NPs), used in clinical practice to assess cardiac dysfunction, exhibit many limitations, however. We used an unbiased proteomics approach for the discovery of novel diagnostic plasma biomarkers of heart failure (HF). METHODS AND RESULTS: A proteomics pipeline adapted for very low-abundant plasma proteins was applied to clinical samples from patients admitted with acute decompensated HF (ADHF). Quiescin Q6 (QSOX1), a protein involved in the formation of disulfide bridges, emerged as the best performing marker for ADHF (with an area under the receiver operator characteristic curve of 0.86, 95% confidence interval: 0.79-0.92), and novel isoforms of NPs were also identified. Diagnostic performance of QSOX1 for ADHF was confirmed in 267 prospectively collected subjects of whom 76 had ADHF. Combining QSOX1 to B-type NP (BNP) significantly improved diagnostic accuracy for ADHF by particularly improving specificity. Using thoracic aortic constriction in rats, QSOX1 was specifically induced within both left atria and ventricles at the time of HF onset. CONCLUSION: The novel biomarker QSOX1 accurately identifies ADHF, particularly when combined with BNP. Through both clinical and experimental studies we provide lines of evidence for a link between ADHF and cardiovascular production of QSOX1.


Assuntos
Insuficiência Cardíaca/diagnóstico , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/sangue , Proteômica/métodos , Idoso , Animais , Aorta Torácica , Biomarcadores/sangue , Estudos de Casos e Controles , Constrição , Dispneia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Ratos
12.
J Biol Chem ; 286(40): 35007-19, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21768101

RESUMO

Alterations in the balance of cytoskeleton as well as energetic proteins are involved in the cardiac remodeling occurring in dilated cardiomyopathy (DCM). We used two-dimensional DIGE proteomics as a discovery approach to identify key molecular changes taking place in a temporally controlled model of DCM triggered by cardiomyocyte-specific serum response factor (SRF) knock-out in mice. We identified muscle creatine kinase (MCK) as the primary down-regulated protein followed by α-actin and α-tropomyosin down-regulation leading to a decrease of polymerized F-actin. The early response to these defects was an increase in the amount of desmin intermediate filaments and phosphorylation of the αB-crystallin chaperone. We found that αB-crystallin and desmin progressively lose their striated pattern and accumulate at the intercalated disk and the sarcolemma, respectively. We further show that desmin is a preferential target of advanced glycation end products (AGE) in mouse and human DCM. Inhibition of CK in cultured cardiomyocytes is sufficient to recapitulate both the actin depolymerization defect and the modification of desmin by AGE. Treatment with either cytochalasin D or glyoxal, a cellular AGE, indicated that both actin depolymerization and AGE contribute to desmin disorganization. Heat shock-induced phosphorylation of αB-crystallin provides a transient protection of desmin against glyoxal in a p38 MAPK-dependent manner. Our results show that the strong down-regulation of MCK activity contributes to F-actin instability and induces post-translational modification of αB-crystallin and desmin. Our results suggest that AGE may play an important role in DCM because they alter the organization of desmin filaments that normally support stress response and mitochondrial functions in cardiomyocytes.


Assuntos
Actinas/metabolismo , Cardiomiopatia Dilatada/metabolismo , Creatina Quinase Forma MM/deficiência , Creatina Quinase Forma MM/genética , Desmina/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Alelos , Animais , Eletroforese em Gel Bidimensional , Ventrículos do Coração/patologia , Homozigoto , Humanos , Espectrometria de Massas/métodos , Camundongos , Modelos Biológicos , Miócitos Cardíacos/citologia , Ratos , Tropomiosina/metabolismo , Cadeia B de alfa-Cristalina/química
13.
J Cardiovasc Pharmacol ; 60(3): 315-21, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22710814

RESUMO

BACKGROUND: Aldosterone antagonists (AAs) have beneficial effects on ventricular histological and electrical remodeling and improve noradrenaline uptake. Adding an AA to a beta-blocker (BB) further improves cardiac mortality in heart failure patients. We investigated if adjunction of a BB modifies beneficial effects of spironolactone on different parameters of the ventricular remodeling. METHODS: A severe myocardial infarction (MI) was produced in rats. Three months after surgery, left ventricular (LV) function was assessed by echocardiography. Fifty-five rats with heart failure were then randomized in 5 groups: sham, MI, and MI treated for 4 weeks with spironolactone (10 mg·kg·d), atenolol (1 mg·kg·d), or both. Holter transducers were implanted to record 24-hour ventricular electrical parameters, mean cycle length (RR) and SD of RR. Before killing, invasive left ventricular end diastolic pressure (LVEDP) was recorded. LV samples were used for histological analysis and catecholamine assay. RESULTS: Rats with MI had significantly increased LVEDP (32 ± 3 vs. 14 ± 1 mm Hg), LV, collagen content (5.8% ± 1.4% vs. 3.6% ± 0.7%), ventricular premature complexes (2.5 10 ± 10 vs. 30 ± 13), and decreased meanRR (164 ± 2 vs. 169 ± 1 milliseconds) and SDRR (3.9 ± 0.2 vs. 5.4 ± 0.2 milliseconds) compared with sham. At nonhypotensive doses, spironolactone and atenolol similarly improved LVEDP. Compared with MI, although spironolactone significantly decreased ventricular premature complexes, LV collagen and noradrenaline contents, and improved meanRR and SDRR, atenolol had effects only on meanRR and SDRR. Addition of atenolol to spironolactone further improved spironolactone effects on all these parameters. CONCLUSIONS: AA improved, independently of the cardiac function, histological and electrical remodeling after MI. A BB added to an AA did not blunt these beneficial effects; furthermore, it improved these effects related to spironolactone.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Insuficiência Cardíaca/patologia , Miocárdio/patologia , Índice de Gravidade de Doença , Espironolactona/administração & dosagem , Remodelação Ventricular/efeitos dos fármacos , Animais , Doença Crônica , Quimioterapia Combinada , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Resultado do Tratamento , Remodelação Ventricular/fisiologia
14.
Mol Cell Biochem ; 347(1-2): 63-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20938722

RESUMO

Hyperhomocysteinemia, characterized by an elevated plasma homocysteine concentration, leads to several clinical manifestations and particularly cardiovascular diseases. Experimental models of hyperhomocysteinemia revealed several tissue injuries including heart fibrosis and ventricular hypertrophy. In order to analyze the molecular mechanisms link to these morphological alterations, a mild hyperhomocysteinemia was induced in rats via a chronic methionine administration. Effects of methionine administration were examined by histological analysis with Sirius red staining, histomorphometric analysis, zymography, and immunoblotting. Hyperhomocysteinemia due to methionine administration produces an interstitial myocardial fibrosis and a ventricular cardiomyocyte hypertrophy, which were associated with increased expression of transforming growth factor-beta1 (TGFß1), tissue inhibitors of metalloproteinase (TIMP) 2, and JNK activation. However, the matrix metalloproteinase 2 activity was decreased in the hearts of hyperhomocysteinemic rats. Moreover, the TIMP1 protein expression was decreased, and the TIMP1-MMP1 balance was shifted. Remodeling in cardiac tissue observed in rat model of mild hyperhomocysteinemia is associated with a dysregulation in extracellular matrix degradation which results, at least in part, from enhancement of TGFß1 level.


Assuntos
Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Colágeno/metabolismo , Ativação Enzimática/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibrose , Homocisteína/sangue , Homocisteína/farmacologia , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Miocárdio/enzimologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/metabolismo
15.
Circ Res ; 105(8): 784-92, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19745166

RESUMO

RATIONALE: Multiple cyclic nucleotide phosphodiesterases (PDEs) degrade cAMP in cardiomyocytes but the role of PDEs in controlling cAMP signaling during pathological cardiac hypertrophy is poorly defined. OBJECTIVE: Evaluate the beta-adrenergic regulation of cardiac contractility and characterize the changes in cardiomyocyte cAMP signals and cAMP-PDE expression and activity following cardiac hypertrophy. METHODS AND RESULTS: Cardiac hypertrophy was induced in rats by thoracic aortic banding over a time period of 5 weeks and was confirmed by anatomic measurements and echocardiography. Ex vivo myocardial function was evaluated in Langendorff-perfused hearts. Engineered cyclic nucleotide-gated (CNG) channels were expressed in single cardiomyocytes to monitor subsarcolemmal cAMP using whole-cell patch-clamp recordings of the associated CNG current (I(CNG)). PDE variant activity and protein level were determined in purified cardiomyocytes. Aortic stenosis rats exhibited a 67% increase in heart weight compared to sham-operated animals. The inotropic response to maximal beta-adrenergic stimulation was reduced by approximately 54% in isolated hypertrophied hearts, along with a approximately 32% decrease in subsarcolemmal cAMP levels in hypertrophied myocytes. Total cAMP hydrolytic activity as well as PDE3 and PDE4 activities were reduced in hypertrophied myocytes, because of a reduction of PDE3A, PDE4A, and PDE4B, whereas PDE4D was unchanged. Regulation of beta-adrenergic cAMP signals by PDEs was blunted in hypertrophied myocytes, as demonstrated by the diminished effects of IBMX (100 micromol/L) and of both the PDE3 inhibitor cilostamide (1 micromol/L) and the PDE4 inhibitor Ro 201724 (10 micromol/L). CONCLUSIONS: Beta-adrenergic desensitization is accompanied by a reduction in cAMP-PDE and an altered modulation of beta-adrenergic cAMP signals in cardiac hypertrophy.


Assuntos
Cardiomegalia/enzimologia , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Regulação Enzimológica da Expressão Gênica , Miócitos Cardíacos/enzimologia , Sistemas do Segundo Mensageiro , 1-Metil-3-Isobutilxantina/farmacologia , 4-(3-Butoxi-4-metoxibenzil)-2-imidazolidinona/farmacologia , Animais , Estenose da Valva Aórtica/enzimologia , Estenose da Valva Aórtica/patologia , Cardiomegalia/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Masculino , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/patologia , Tamanho do Órgão , Inibidores da Fosfodiesterase 4 , Inibidores de Fosfodiesterase/farmacologia , Quinolonas/farmacologia , Ratos , Ratos Wistar
16.
Genomics ; 96(2): 73-81, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20417270

RESUMO

The role of hyaluronan in cardiac growth has become evident, previously shown by increased myocardial levels of hyaluronan in a rat model of cardiac hypertrophy. To further investigate the role of hyaluronan and regulation of its synthesis in cardiac hypertrophy, quantitative measurements of myocardial hyaluronan concentration was correlated to gene transcription in hypertrophic cardiac tissue. Factor analysis was used to study this correlation over time. A subset of differentially expressed genes was identified with a transcriptional regulation correlating to the increased synthesis of hyaluronan, suggesting a common regulatory pathway. Four transcription factors, Myc, Fos, Junb and Egr1, were also up-regulated. Furthermore, the Ace gene was up-regulated, representing increase of angiotensin II, an inducer of these transcription factors and fetal genes in cardiac hypertrophy. This demonstrates a coordinated synthesis of hyaluronan and pro-hypertrophic gene expression, regulated by immediate early genes, with angiotensin II as a possible mediator.


Assuntos
Cardiomegalia/metabolismo , Regulação da Expressão Gênica/fisiologia , Ácido Hialurônico/biossíntese , Miocárdio/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Cardiomegalia/genética , Análise Fatorial , Regulação da Expressão Gênica/genética , Genes Precoces/genética , Genes Precoces/fisiologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrofotometria , Estatísticas não Paramétricas , Fatores de Tempo , Fatores de Transcrição/metabolismo
17.
ESC Heart Fail ; 8(2): 928-937, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33529501

RESUMO

AIMS: Our objectives were to validate a murine model of chronic cardiotoxicity induced by Doxorubicin (Dox) and Trastuzumab (Trast) and to test the potential cardio-protective effect of metoprolol. METHODS AND RESULTS: Male C57Bl6 mice were intraperitoneally injected during 2 weeks with Dox (24 mg/kg) or saline, and then with Trast (10 mg/kg) or saline for two more weeks. Half of the mice received metoprolol (100 mg/kg). Cardiotoxicity was defined by a decline in left ventricular ejection fraction (LVEF) ≥ 10 points. At Day 42, Dox + Trast-treated mice exhibited a 13-points decline in LVEF (74 ± 2.6% vs. 87 ± 0.8% for control mice, P < 0.001) and a severe cardiac atrophy (heart weight: 105 ± 2.7 mg vs. 119 ± 3.9 mg for control mice, P < 0.01). This cardiac atrophy resulted from an excess of cardiac necrosis (assessed by plasma cardiac troponin I level: 3.2 ± 0.4 ng/L vs. 1.3 ± 0.06 ng/L for control mice, P < 0.01), an increase in apoptosis (caspase 3 activity showing a six-fold increase for Dox + Trast-treated mice vs. controls, P < 0.001), and cardiomyocyte atrophy (myocyte size: 0.67 ± 0.08 µm2 vs. 1.36 ± 0.10 µm2 for control mice, P < 0.001). In addition, Dox + Trast-treated mice were shown to have an increased cardiac oxidative stress (164 ± 14 dihydroethidine-marked nuclei per area vs. 56 ± 9.5 for control mice, P < 0.01) and increased cardiac fibrosis (the semi-quantitative fibrosis score was three-fold higher for Dox + Trast-treated mice as compared with controls, P < 0.01). Metoprolol was not able to prevent either the decrease in LVEF or the severe cardiac atrophy, the cardiac necrosis, and the cardiac remodelling induced by chemotherapies. CONCLUSION: A murine model of chronic cardiotoxicity induced by Dox and Trast was characterized by a decrease in cardiac function, a cardiac apoptosis and necrosis leading to cardiomyocyte atrophy. Metoprolol did not prevent this cardiotoxicity.


Assuntos
Cardiotoxicidade , Metoprolol , Animais , Doxorrubicina/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Volume Sistólico , Trastuzumab/efeitos adversos , Função Ventricular Esquerda
18.
FASEB J ; 23(7): 2176-85, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19255254

RESUMO

Recent reports showed an unexpected worsening of endothelial function by aldosterone antagonism in diabetic patients, suggesting that aldosterone could interfere with the detrimental consequences of diabetes on microvasculature and thus on cardiac function. To test this hypothesis, diabetes (D) was induced using streptozotocin in transgenic (Tg) male mice overexpressing aldosterone-synthase in the heart and in wild-type (Wt) mice. Eight weeks after streptozotocin injection, impairment of left ventricular systolic function, measured by echocardiography (fractional shortening), was accompanied by a decrease in capillaries/cardiomyocyte ratio (-20%) and VEGFa expression (-40%) in Wt-D mice compared with normoglycemic littermates. Furthermore, Wt-D mice demonstrated an increase in superoxide production (+100%) and protein carbonylation (+33%), hallmarks of oxidative stress. Except for a slight increase in protein carbonylation, all of these diabetes-associated cardiac alterations were undetectable in Tg-D mice. Fibrosis was induced similarly in both diabetic groups. Eplerenone (an aldosterone antagonist) abolished all of the effects of aldosterone-synthase overexpression but had no effect in Wt-D mice. Thus, aldosterone prevents systolic dysfunction through a mineralocorticoid receptor-dependent mechanism that may include preventing VEGFa down-regulation and maintaining capillary density. Understanding how aldosterone prevents VEGFa down-regulation in experimental diabetes could be important to define new strategies targeting the prevention of a decrease in capillary density.


Assuntos
Aldosterona/fisiologia , Capilares , Vasos Coronários , Regulação da Expressão Gênica/fisiologia , Fator A de Crescimento do Endotélio Vascular/genética , Aldosterona/genética , Animais , Complicações do Diabetes , Diabetes Mellitus Experimental , Coração , Camundongos , Miocárdio , Receptores de Mineralocorticoides/fisiologia , Sístole , Disfunção Ventricular Esquerda
19.
Circ Res ; 102(8): 959-65, 2008 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-18323524

RESUMO

Cardiac hypertrophy is promoted by adrenergic overactivation and can progress to heart failure, a leading cause of mortality worldwide. Although cAMP is among the most well-known signaling molecules produced by beta-adrenergic receptor stimulation, its mechanism of action in cardiac hypertrophy is not fully understood. The identification of Epac (exchange protein directly activated by cAMP) proteins as novel sensors for cAMP has broken the dogma surrounding cAMP and protein kinase A. However, their role and regulation in the mature heart remain to be defined. Here, we show that cardiac hypertrophy induced by thoracic aortic constriction increases Epac1 expression in rat myocardium. Adult ventricular myocytes isolated from banded animals display an exaggerated cellular growth in response to Epac activation. At the molecular level, Epac1 hypertrophic effects are independent of its classic effector, Rap1, but rather involve the small GTPase Ras, the phosphatase calcineurin, and Ca(2+)/calmodulin-dependent protein kinase II. Importantly, we find that in response to beta-adrenergic receptor stimulation, Epac1 activates Ras and induces adult cardiomyocyte hypertrophy in a cAMP-dependent but protein kinase A-independent manner. Knockdown of Epac1 strongly reduces beta-adrenergic receptor-induced hypertrophic program. Finally, we report for the first time that Epac1 is mainly expressed in human heart as compared with Epac2 isoform and is increased in heart failure. Taken together, our data demonstrate that the guanine nucleotide exchange factor Epac1 contributes to the hypertrophic effect of beta-adrenergic receptor in a protein kinase A-independent fashion and may, therefore, represent a novel therapeutic target for the treatment of cardiac disorders.


Assuntos
Cardiomegalia/etiologia , Fatores de Troca do Nucleotídeo Guanina/análise , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Hipertrofia/etiologia , Miócitos Cardíacos/patologia , Receptores Adrenérgicos beta/fisiologia , Animais , Calcineurina , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de AMP Cíclico , Humanos , Ratos , Ratos Wistar , Proteínas ras
20.
PLoS One ; 15(8): e0238039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853284

RESUMO

Sepsis is a global economic and health burden. Dipeptidyl peptidase 3 (DPP3) is elevated in the plasma of septic patients. The highest levels of circulating DPP3 (cDPP3) are found in non-survivor septic shock patients. The aim of this study was to evaluate the benefits of inhibiting cDPP3 by a specific antibody, Procizumab (PCZ), on cardiac function in an experimental model of sepsis, the caecal ligature and puncture (CLP) model. Rats were monitored by invasive blood pressure and echocardiography. Results are presented as mean ± SD, with p <0.05 considered significant. PCZ rapidly restored left ventricular shortening fraction (from 39 ± 4% to 51 ± 2% before and 30 min after PCZ administration (p = 0.004)). Cardiac output and stroke volume were higher in the CLP + PCZ group when compared to the CLP + PBS group (152 ± 33 mL/min vs 97 ± 25 mL/min (p = 0.0079), and 0.5 ± 0.1 mL vs 0.3 ± 1.0 mL (p = 0.009), respectively) with a markedly reduced plasma DPP3 activity (138 ± 70 U/L in CLP + PCZ group versus 735 ± 255 U/L (p = 0.048) in the CLP + PBS group). Of note, PCZ rapidly reduced oxidative stress in the heart of the CLP + PCZ group when compared to those of the CLP + PBS group (13.3 ± 8.2 vs 6.2 ± 2.5 UI, p = 0.005, 120 min after administration, respectively). Our study demonstrates that inhibition of cDPP3 by PCZ restored altered cardiac function during sepsis in rats.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores , Dipeptidil Peptidases e Tripeptidil Peptidases/sangue , Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Sepse/sangue , Sepse/fisiopatologia , Animais , Modelos Animais de Doenças , Hemodinâmica/efeitos dos fármacos , Masculino , Estudo de Prova de Conceito , Ratos , Ratos Wistar , Sepse/enzimologia , Sístole/efeitos dos fármacos , Sístole/fisiologia
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