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1.
PLoS One ; 17(2): e0263312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35213570

RESUMO

BACKGROUND: It remains unclear as to whether polycystic ovary syndrome (PCOS) is an additional risk factor in the development of left ventricular (LV) hypertrophy in obese women. In the current study, we provide clarity on this issue by rigorously analysing patient LV geometry beyond the basic clinical measures currently used. Importantly, the cohort contained only normotensive patients that would normally be deemed low risk with no further intervention required. METHODS: The study comprised 24 obese women with PCOS and 29 obese Control women. Transthoracic echocardiography was used to evaluate LV structure/function. Basic clinical and metabolic data were collected for each participant consisting of age, BMI, blood pressure, fasting glucose, LDL-C, HLD-C, cholesterol and triglyceride levels. Exclusion criteria; BMI < 30 g/m2, type 2 diabetes, hypertension. RESULTS: Both groups exhibited concentric remodelling of the LV posterior wall at a prevalence of ~20%, this associated with grade 1 diastolic dysfunction. Estimated LV mass/height2.7 was increased patients with PCOS (45 ± 2.2 vs 37 ± 1.6) with 33% exhibiting LV mass/height2.7 above ASE guidelines, compared to 7% in Controls. Furthermore, 25% of patients with PCOS were characterised with concentric hypertrophy, an alteration in LV geometry that was not observed in the Control group. CONCLUSIONS: To our knowledge, this is the first study to assess LV geometric patterns in obese women with PCOS. The results suggest that obese women with PCOS are at greater risk of concentric hypertrophy than obese only women and provide justification for additional cardiovascular risk assessment in normotensive obese/PCOS women.


Assuntos
Ecocardiografia , Hipertrofia Ventricular Esquerda/diagnóstico , Obesidade/diagnóstico por imagem , Síndrome do Ovário Policístico/diagnóstico por imagem , Adulto , Glicemia , Pressão Sanguínea , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Insuficiência Cardíaca Diastólica/complicações , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/patologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Hipertrofia Ventricular Esquerda/sangue , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Obesidade/sangue , Obesidade/complicações , Obesidade/patologia , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/patologia , Triglicerídeos/sangue , Função Ventricular Esquerda/fisiologia
2.
J Am Coll Cardiol ; 77(4): 405-419, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33509397

RESUMO

BACKGROUND: Whereas heart failure with reduced ejection fraction (HFrEF) is associated with ventricular dilation and markedly reduced systolic function, heart failure with preserved ejection fraction (HFpEF) patients exhibit concentric hypertrophy and diastolic dysfunction. Impaired cardiomyocyte Ca2+ homeostasis in HFrEF has been linked to disruption of membrane invaginations called t-tubules, but it is unknown if such changes occur in HFpEF. OBJECTIVES: This study examined whether distinct cardiomyocyte phenotypes underlie the heart failure entities of HFrEF and HFpEF. METHODS: T-tubule structure was investigated in left ventricular biopsies obtained from HFrEF and HFpEF patients, whereas cardiomyocyte Ca2+ homeostasis was studied in rat models of these conditions. RESULTS: HFpEF patients exhibited increased t-tubule density in comparison with control subjects. Super-resolution imaging revealed that higher t-tubule density resulted from both tubule dilation and proliferation. In contrast, t-tubule density was reduced in patients with HFrEF. Augmented collagen deposition within t-tubules was observed in HFrEF but not HFpEF hearts. A causative link between mechanical stress and t-tubule disruption was supported by markedly elevated ventricular wall stress in HFrEF patients. In HFrEF rats, t-tubule loss was linked to impaired systolic Ca2+ homeostasis, although diastolic Ca2+ removal was also reduced. In contrast, Ca2+ transient magnitude and release kinetics were largely maintained in HFpEF rats. However, diastolic Ca2+ impairments, including reduced sarco/endoplasmic reticulum Ca2+-ATPase activity, were specifically observed in diabetic HFpEF but not in ischemic or hypertensive models. CONCLUSIONS: Although t-tubule disruption and impaired cardiomyocyte Ca2+ release are hallmarks of HFrEF, such changes are not prominent in HFpEF. Impaired diastolic Ca2+ homeostasis occurs in both conditions, but in HFpEF, this mechanism for diastolic dysfunction is etiology-dependent.


Assuntos
Cálcio/metabolismo , Insuficiência Cardíaca Diastólica/etiologia , Miócitos Cardíacos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/patologia , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/patologia
3.
Cardiovasc Res ; 117(9): 2108-2124, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32871009

RESUMO

AIMS: Heart failure with preserved ejection fraction (HFpEF) is a multifactorial disease that constitutes several distinct phenotypes, including a common cardiometabolic phenotype with obesity and type 2 diabetes mellitus. Treatment options for HFpEF are limited, and development of novel therapeutics is hindered by the paucity of suitable preclinical HFpEF models that recapitulate the complexity of human HFpEF. Metabolic drugs, like glucagon-like peptide receptor agonist (GLP-1 RA) and sodium-glucose co-transporter 2 inhibitors (SGLT2i), have emerged as promising drugs to restore metabolic perturbations and may have value in the treatment of the cardiometabolic HFpEF phenotype. We aimed to develop a multifactorial HFpEF mouse model that closely resembles the cardiometabolic HFpEF phenotype, and evaluated the GLP-1 RA liraglutide (Lira) and the SGLT2i dapagliflozin (Dapa). METHODS AND RESULTS: Aged (18-22 months old) female C57BL/6J mice were fed a standardized chow (CTRL) or high-fat diet (HFD) for 12 weeks. After 8 weeks HFD, angiotensin II (ANGII), was administered for 4 weeks via osmotic mini pumps. HFD + ANGII resulted in a cardiometabolic HFpEF phenotype, including obesity, impaired glucose handling, and metabolic dysregulation with inflammation. The multiple hit resulted in typical clinical HFpEF features, including cardiac hypertrophy and fibrosis with preserved fractional shortening but with impaired myocardial deformation, atrial enlargement, lung congestion, and elevated blood pressures. Treatment with Lira attenuated the cardiometabolic dysregulation and improved cardiac function, with reduced cardiac hypertrophy, less myocardial fibrosis, and attenuation of atrial weight, natriuretic peptide levels, and lung congestion. Dapa treatment improved glucose handling, but had mild effects on the HFpEF phenotype. CONCLUSIONS: We developed a mouse model that recapitulates the human HFpEF disease, providing a novel opportunity to study disease pathogenesis and the development of enhanced therapeutic approaches. We furthermore show that attenuation of cardiometabolic dysregulation may represent a novel therapeutic target for the treatment of HFpEF.


Assuntos
Compostos Benzidrílicos/farmacologia , Glucosídeos/farmacologia , Insuficiência Cardíaca Diastólica/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Incretinas/farmacologia , Liraglutida/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Angiotensina II , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Fibrose , Regulação da Expressão Gênica , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Transdução de Sinais
4.
Curr HIV/AIDS Rep ; 16(5): 371-380, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31482297

RESUMO

PURPOSE: People with HIV (PHIV) with access to modern antiretroviral therapy (ART) face a two-fold increased risk of heart failure as compared with non-HIV-infected individuals. The purpose of this review is to consider evolving risks, mechanisms, and preventive considerations pertaining to heart failure among PHIV. RECENT FINDINGS: While unchecked HIV/AIDS has been documented to precipitate heart failure characterized by overtly reduced cardiac contractile function, ART-treated HIV may be associated with either heart failure with reduced ejection fraction (HFrEF) or with heart failure with preserved ejection fraction (HFpEF). In HFpEF, a "stiff" left ventricle cannot adequately relax in diastole-a condition known as diastolic dysfunction. Diastolic dysfunction, in turn, may result from processes including myocardial fibrosis (triggered by hypertension and/or immune activation/inflammation) and/or myocardial steatosis (triggered by metabolic dysregulation). Notably, hypertension, systemic immune activation, and metabolic dysregulation are all common conditions among even those PHIV who are well-treated with ART. Of clinical consequence, HFpEF is uniquely intransigent to conventional medical therapies and portends high morbidity and mortality. However, diastolic dysfunction is reversible-as are contributing processes of myocardial fibrosis and myocardial steatosis. Our challenges in preserving myocardial health among PHIV are two-fold. First, we must continue working to realize UNAIDS 90-90-90 goals. This achievement will reduce AIDS-related mortality, including cardiovascular deaths from AIDS-associated heart failure. Second, we must work to elucidate the detailed mechanisms continuing to predispose ART-treated PHIV to heart failure and particularly HFpEF. Such efforts will enable the development and implementation of targeted preventive strategies.


Assuntos
Infecções por HIV/complicações , Insuficiência Cardíaca Diastólica/epidemiologia , Insuficiência Cardíaca Diastólica/patologia , Volume Sistólico/fisiologia , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Humanos , Inflamação , Masculino
5.
J Diabetes Complications ; 33(8): 579-584, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31155469

RESUMO

AIMS: To identify prevalence and predictors of undetected pre-clinical diastolic dysfunction (PDD) in a cohort of adult Hispanic patients with type 2 diabetes (T2D), and compare variations in epidemiology and echocardiographic characteristics between categorization based on the 2009 versus 2016 guidelines. METHODS: From 2013 to 2016, a cross-sectional cohort study of adults with T2D was performed. Patients without signs/symptoms of heart failure (HF) underwent 2D/Doppler echocardiographic screening, and were grouped into two subcohorts: 1) normal diastolic function, and 2) PDD, defined by the 2009 or 2016 ASE/EACVI criteria. RESULTS: Among 307 Hispanic subjects, by 2009 criteria, 193 (62.9%) had normal diastolic function, 113 (36.8%) diastolic dysfunction and 1 (0.3%) indeterminate. Those that had diastolic dysfunction (DD) were older (mean age 59.1 ±â€¯12.7 vs 52.2 ±â€¯12.2 years, p< 0.0001), with higher proportion female (69.0 vs 53.9%, p = 0.0092), and higher systolic blood pressure (136.5 ±â€¯18.6 vs 131.7 ±â€¯19.9, p = 0.0372). By 2016 criteria, 261 (85%) had normal diastolic function, 22 (7.2%) diastolic dysfunction and 24 (7.8%) indeterminate. Among those that had normal diastolic function (n = 261) by 2016 criteria, 29% (n = 76) had DD by 2009 criteria, and they were more likely to have higher E/e' and left atrial volume index (LAVI). CONCLUSIONS: By applying the 2016 versus the 2009 diastolic function criteria to a Hispanic population with T2D, the prevalence of PDD decreased significantly from 37% to 7%. These findings are consistent with recent studies demonstrating that the 2016 ASE/EACVI guidelines are more specific for diagnosing DD and hence less sensitive leading to lower prevalence of diastolic dysfunction.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Ecocardiografia , Insuficiência Cardíaca Diastólica/diagnóstico , Insuficiência Cardíaca Diastólica/epidemiologia , Hispânico ou Latino/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Adulto , Idoso , Índice de Massa Corporal , Estudos de Coortes , Comorbidade , Estudos Transversais , Diástole/fisiologia , Feminino , Insuficiência Cardíaca Diastólica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade
6.
J Am Coll Cardiol ; 73(21): 2705-2718, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31146816

RESUMO

BACKGROUND: Patients with chronic kidney disease (CKD) and coincident heart failure with preserved ejection fraction (HFpEF) may constitute a distinct HFpEF phenotype. Osteopontin (OPN) is a biomarker of HFpEF and predictive of disease outcome. We recently reported that OPN blockade reversed hypertension, mitochondrial dysfunction, and kidney failure in Col4a3-/- mice, a model of human Alport syndrome. OBJECTIVES: The purpose of this study was to identify potential OPN targets in biopsies of HF patients, healthy control subjects, and human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs), and to characterize the cardiac phenotype of Col4a3-/- mice, relate this to HFpEF, and investigate possible causative roles for OPN in driving the cardiomyopathy. METHODS: OGDHL mRNA and protein were quantified in myocardial samples from patients with HFpEF, heart failure with reduced ejection fraction, and donor control subjects. OGDHL expression was quantified in hiPS-CMs treated with or without anti-OPN antibody. Cardiac parameters were evaluated in Col4a3-/- mice with and without global OPN knockout or AAV9-mediated delivery of 2-oxoglutarate dehydrogenase-like (Ogdhl) to the heart. RESULTS: OGDHL mRNA and protein displayed abnormal abundances in cardiac biopsies of HFpEF (n = 17) compared with donor control subjects (n = 12; p < 0.01) or heart failure with reduced ejection fraction patients (n = 12; p < 0.05). Blockade of OPN in hiPS-CMs conferred increased OGDHL expression. Col4a3-/- mice demonstrated cardiomyopathy with similarities to HFpEF, including diastolic dysfunction, cardiac hypertrophy and fibrosis, pulmonary edema, and impaired mitochondrial function. The cardiomyopathy was ameliorated by Opn-/- coincident with improved renal function and increased expression of Ogdhl. Heart-specific overexpression of Ogdhl in Col4a3-/- mice also improved cardiac function and cardiomyocyte energy state. CONCLUSIONS: Col4a3-/- mice present a model of HFpEF secondary to CKD wherein OPN and OGDHL are intermediates, and possibly therapeutic targets.


Assuntos
Modelos Animais de Doenças , Insuficiência Cardíaca Diastólica/etiologia , Complexo Cetoglutarato Desidrogenase/metabolismo , Osteopontina/metabolismo , Disfunção Ventricular Esquerda/etiologia , Animais , Autoantígenos/genética , Colágeno Tipo IV/genética , Fibrose , Terapia Genética , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/terapia , Complexo Cetoglutarato Desidrogenase/genética , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Nefrite Hereditária/complicações , Osteopontina/genética , Estresse Oxidativo , Disfunção Ventricular Esquerda/metabolismo
7.
Gene ; 697: 11-18, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-30763670

RESUMO

OBJECTIVE: To explore the effect of adeno-associated virus 9-mediated RNA interference targeting SOCS3 (AAV9-SOCS3 siRNA) on the treatment of diastolic heart failure (DHF). METHOD: A rat DHF model was established, and cardiac function and hemodynamic changes were measured. HE, Sirius red and TUNEL staining were applied to observe the pathological changes in the myocardium. Immunoblotting and immunohistochemical staining were utilized to detect SOCS3 expression. The expression levels of various factors, including fibrosis-related factors (collagen I, collagen II, α-SMA and TGF-ß), inflammatory-related factors (IL-1ß, IL-6, TNF-α, p-p65 and ICAM-1) and factors related to the JAK/STAT signal pathway were analyzed by immunoblotting and/or qPCR. The serum levels of IL-1ß, IL-6, and TNF-α were measured using ELISA. RESULTS: SOCS3 expression was significantly downregulated in the DHF rat model by SOCS3 siRNA delivery. In the successfully established DHF rat model, cardiac function was clearly decreased, and cardiomyocyte apoptosis and myocardial fibrosis were significantly increased. These changes were ameliorated by treatment with AAV9-SOCS3 siRNA. The expression levels of p-JAK2 and p-STAT3 were significantly upregulated in the AAV9-SOCS3 siRNA group compared with the sham and AAV9-siRNA control groups, indicating that SOCS3 is a negative regulator of this signaling pathway. The expression levels of collagen I/III, α-SMA and TGF-ß were also decreased at both the mRNA and protein levels. In addition, the serum and myocardial tissue expression levels of inflammatory-related factors, such as IL-6, IL-1ß, and TNF-α, were also reduced by the administration of AAV9-SOCS3 siRNA compared with the AAV9-siRNA control. CONCLUSIONS: SOCS3 gene silencing by AAV9-SOCS3 siRNA administration in a DHF rat model significantly reduced myocardial fibrosis and the inflammatory response and improved heart function. Therefore, this treatment is a potential therapeutic method for treating DHF.


Assuntos
Insuficiência Cardíaca Diastólica/genética , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Actinas/metabolismo , Animais , Apoptose/fisiologia , Dependovirus/genética , Modelos Animais de Doenças , Inativação Gênica , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/patologia , Hemodinâmica , Interleucina-1beta/sangue , Interleucina-6/sangue , Janus Quinase 2/metabolismo , Masculino , Interferência de RNA , RNA Interferente Pequeno/genética , Ratos , Ratos Wistar , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/sangue
9.
Circ Res ; 121(5): 575-583, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28630135

RESUMO

RATIONALE: Cardiac fibroblasts (CFs) drive extracellular matrix remodeling after pressure overload, leading to fibrosis and diastolic dysfunction. Recent studies described the role of long noncoding RNAs (lncRNAs) in cardiac pathologies. Nevertheless, detailed reports on lncRNAs regulating CF biology and describing their implication in cardiac remodeling are still missing. OBJECTIVE: Here, we aimed at characterizing lncRNA expression in murine CFs after chronic pressure overload to identify CF-enriched lncRNAs and investigate their function and contribution to cardiac fibrosis and diastolic dysfunction. METHODS AND RESULTS: Global lncRNA profiling identified several dysregulated transcripts. Among them, the lncRNA maternally expressed gene 3 (Meg3) was found to be mostly expressed by CFs and to undergo transcriptional downregulation during late cardiac remodeling. In vitro, Meg3 regulated the production of matrix metalloproteinase-2 (MMP-2). GapmeR-mediated silencing of Meg3 in CFs resulted in the downregulation of Mmp-2 transcription, which, in turn, was dependent on P53 activity both in the absence and in the presence of transforming growth factor-ß I. Chromatin immunoprecipitation showed that further induction of Mmp-2 expression by transforming growth factor-ß I was blocked by Meg3 silencing through the inhibition of P53 binding on the Mmp-2 promoter. Consistently, inhibition of Meg3 in vivo after transverse aortic constriction prevented cardiac MMP-2 induction, leading to decreased cardiac fibrosis and improved diastolic performance. CONCLUSIONS: Collectively, our findings uncover a critical role for Meg3 in the regulation of MMP-2 production by CFs in vitro and in vivo, identifying a new player in the development of cardiac fibrosis and potential new target for the prevention of cardiac remodeling.


Assuntos
Fibroblastos/metabolismo , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/prevenção & controle , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/metabolismo , Animais , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Cardiomiopatias/prevenção & controle , Células Cultivadas , Fibroblastos/patologia , Fibrose/metabolismo , Fibrose/patologia , Fibrose/prevenção & controle , Insuficiência Cardíaca Diastólica/patologia , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/patologia , Ratos , Remodelação Ventricular/fisiologia
10.
J Clin Invest ; 127(5): 1600-1612, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28459429

RESUMO

The cardiac extracellular matrix (ECM) not only provides mechanical support, but also transduces essential molecular signals in health and disease. Following myocardial infarction, dynamic ECM changes drive inflammation and repair. Early generation of bioactive matrix fragments activates proinflammatory signaling. The formation of a highly plastic provisional matrix facilitates leukocyte infiltration and activates infarct myofibroblasts. Deposition of matricellular proteins modulates growth factor signaling and contributes to the spatial and temporal regulation of the reparative response. Mechanical stress due to pressure and volume overload and metabolic dysfunction also induce profound changes in ECM composition that contribute to the pathogenesis of heart failure. This manuscript reviews the role of the ECM in cardiac repair and remodeling and discusses matrix-based therapies that may attenuate remodeling while promoting repair and regeneration.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Insuficiência Cardíaca Diastólica/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Matriz Extracelular/imunologia , Matriz Extracelular/patologia , Proteínas da Matriz Extracelular/imunologia , Insuficiência Cardíaca Diastólica/imunologia , Insuficiência Cardíaca Diastólica/patologia , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Leucócitos/patologia , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Miocárdio/imunologia , Miocárdio/patologia , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/patologia , Transdução de Sinais/imunologia , Estresse Mecânico
11.
J Am Heart Assoc ; 6(1)2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28115312

RESUMO

BACKGROUND: Sex-related differences in cardiac function and iron metabolism exist in humans and experimental animals. Male patients and preclinical animal models are more susceptible to cardiomyopathies and heart failure. However, whether similar differences are seen in iron-overload cardiomyopathy is poorly understood. METHODS AND RESULTS: Male and female wild-type and hemojuvelin-null mice were injected and fed with a high-iron diet, respectively, to develop secondary iron overload and genetic hemochromatosis. Female mice were completely protected from iron-overload cardiomyopathy, whereas iron overload resulted in marked diastolic dysfunction in male iron-overloaded mice based on echocardiographic and invasive pressure-volume analyses. Female mice demonstrated a marked suppression of iron-mediated oxidative stress and a lack of myocardial fibrosis despite an equivalent degree of myocardial iron deposition. Ovariectomized female mice with iron overload exhibited essential pathophysiological features of iron-overload cardiomyopathy showing distinct diastolic and systolic dysfunction, severe myocardial fibrosis, increased myocardial oxidative stress, and increased expression of cardiac disease markers. Ovariectomy prevented iron-induced upregulation of ferritin, decreased myocardial SERCA2a levels, and increased NCX1 levels. 17ß-Estradiol therapy rescued the iron-overload cardiomyopathy in male wild-type mice. The responses in wild-type and hemojuvelin-null female mice were remarkably similar, highlighting a conserved mechanism of sex-dependent protection from iron-overload-mediated cardiac injury. CONCLUSIONS: Male and female mice respond differently to iron-overload-mediated effects on heart structure and function, and females are markedly protected from iron-overload cardiomyopathy. Ovariectomy in female mice exacerbated iron-induced myocardial injury and precipitated severe cardiac dysfunction during iron-overload conditions, whereas 17ß-estradiol therapy was protective in male iron-overloaded mice.


Assuntos
Cardiomiopatias/metabolismo , Insuficiência Cardíaca Diastólica/metabolismo , Hemocromatose/metabolismo , Sobrecarga de Ferro/metabolismo , Estresse Oxidativo , Animais , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Dieta , Ecocardiografia , Estradiol/farmacologia , Feminino , Ferritinas/metabolismo , Fibrose , Proteínas Ligadas por GPI , Coração/efeitos dos fármacos , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/etiologia , Insuficiência Cardíaca Diastólica/patologia , Hemocromatose/complicações , Hemocromatose/patologia , Proteína da Hemocromatose , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/patologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Miocárdio/patologia , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Fatores Sexuais , Trocador de Sódio e Cálcio/metabolismo
12.
Eur Heart J ; 38(13): 942-954, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27147609

RESUMO

The terms used to describe different states of myocardial health and disease are poorly defined. Imprecision and inconsistency in nomenclature can lead to difficulty in interpreting and applying trial outcomes to clinical practice. In particular, the terms 'viable' and 'hibernating' are commonly applied interchangeably and incorrectly to myocardium that exhibits chronic contractile dysfunction in patients with ischaemic heart disease. The range of inherent differences amongst imaging modalities used to define myocardial health and disease add further challenges to consistent definitions. The results of several large trials have led to renewed discussion about the classification of dysfunctional myocardial segments. This article aims to describe the diverse myocardial pathologies that may affect the myocardium in ischaemic heart disease and cardiomyopathy, and how they may be assessed with non-invasive imaging techniques in order to provide a taxonomy of myocardial dysfunction.


Assuntos
Cardiomiopatia Dilatada/patologia , Cardiomiopatia Hipertrófica/patologia , Isquemia Miocárdica/patologia , Doença Aguda , Técnicas de Imagem Cardíaca/métodos , Cardiomiopatia Dilatada/classificação , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Hipertrófica/classificação , Cardiomiopatia Hipertrófica/metabolismo , Doença Crônica , Coração/fisiologia , Insuficiência Cardíaca Diastólica/classificação , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/patologia , Humanos , Infarto do Miocárdio/classificação , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Isquemia Miocárdica/classificação , Isquemia Miocárdica/metabolismo , Miocárdio Atordoado/classificação , Miocárdio Atordoado/metabolismo , Miocárdio Atordoado/patologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Terminologia como Assunto
13.
Int J Cardiovasc Imaging ; 32(7): 1071-80, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27076221

RESUMO

Myocardial reflectivity, as assessed by calibrated integrated backscatter (cIB) analysis, is a non-invasive surrogate for the amount of left ventricular (LV) fibrosis. The aim of this study was to assess the myocardial reflectivity pattern in patients with heart failure and preserved ejection fraction (HFpEF), and to evaluate its relationship with longitudinal systolic deformation of LV by 2D-speckle tracking echocardiography, and degree of diastolic dysfunction. Transthoracic echocardiography, myocardial Doppler-derived systolic (Sm) and early diastolic velocity (E'), global longitudinal strain (GLS), and tissue characterization by cIB, were obtained in 86 subjects, 46 with HFpEF, and 40 controls. GLS was significantly impaired in HFpEF patients (-15.4 ± 3.5 % vs -21.5 ± 2.9 % in controls; P < 0.0001). Increased myocardial reflectivity, as evidenced by less negative values of cIB, was also found in HFpEF compared to controls (-21.2 ± 4.4 dB vs -25.3 ± 3.9 dB, P < 0.0001). In HFpEF patients, myocardial reflectivity was positively related to GLS (r = 0.68, P < 0.0001), E/E' ratio (r = 0.38, P = 0.009), and Tau (r = 0.43, P = 0.002), and inversely related to E' velocity (r = -0.46, P = 0.0012). These associations remained significant after adjustment for age, preload and afterload indices. Patients with HFpEF show changes of LV structure consistent with enhanced fibrosis-as evidenced by increased myocardial reflectivity- which parallel the degree of diastolic dysfunction, and of longitudinal systolic dysfunction.


Assuntos
Ecocardiografia Doppler/métodos , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Miocárdio/patologia , Volume Sistólico , Função Ventricular Esquerda , Remodelação Ventricular , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Fibrose , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Espalhamento de Radiação , Estresse Mecânico
14.
Ann Biomed Eng ; 44(1): 112-27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26043672

RESUMO

Chronic heart failure is a medical condition that involves structural and functional changes of the heart and a progressive reduction in cardiac output. Heart failure is classified into two categories: diastolic heart failure, a thickening of the ventricular wall associated with impaired filling; and systolic heart failure, a dilation of the ventricles associated with reduced pump function. In theory, the pathophysiology of heart failure is well understood. In practice, however, heart failure is highly sensitive to cardiac microstructure, geometry, and loading. This makes it virtually impossible to predict the time line of heart failure for a diseased individual. Here we show that computational modeling allows us to integrate knowledge from different scales to create an individualized model for cardiac growth and remodeling during chronic heart failure. Our model naturally connects molecular events of parallel and serial sarcomere deposition with cellular phenomena of myofibrillogenesis and sarcomerogenesis to whole organ function. Our simulations predict chronic alterations in wall thickness, chamber size, and cardiac geometry, which agree favorably with the clinical observations in patients with diastolic and systolic heart failure. In contrast to existing single- or bi-ventricular models, our new four-chamber model can also predict characteristic secondary effects including papillary muscle dislocation, annular dilation, regurgitant flow, and outflow obstruction. Our prototype study suggests that computational modeling provides a patient-specific window into the progression of heart failure with a view towards personalized treatment planning.


Assuntos
Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Insuficiência Cardíaca Sistólica/patologia , Insuficiência Cardíaca Sistólica/fisiopatologia , Modelos Cardiovasculares , Doença Crônica , Humanos
15.
Eur Heart J ; 37(5): 449-54, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26497163

RESUMO

Cardiac performance is normally determined by architectural, cellular, and molecular structures that determine the heart's form, and by physiological and biochemical mechanisms that regulate the function of these structures. Impaired adaptation of form to function in failing hearts contributes to two syndromes initially called systolic heart failure (SHF) and diastolic heart failure (DHF). In SHF, characterized by high end-diastolic volume (EDV), the left ventricle (LV) cannot eject a normal stroke volume (SV); in DHF, with normal or low EDV, the LV cannot accept a normal venous return. These syndromes are now generally defined in terms of ejection fraction (EF): SHF became 'heart failure with reduced ejection fraction' (HFrEF) while DHF became 'heart failure with normal or preserved ejection fraction' (HFnEF or HFpEF). However, EF is a chimeric index because it is the ratio between SV--which measures function, and EDV--which measures form. In SHF the LV dilates when sarcomere addition in series increases cardiac myocyte length, whereas sarcomere addition in parallel can cause concentric hypertrophy in DHF by increasing myocyte thickness. Although dilatation in SHF allows the LV to accept a greater venous return, it increases the energy cost of ejection and initiates a vicious cycle that contributes to progressive dilatation. In contrast, concentric hypertrophy in DHF facilitates ejection but impairs filling and can cause heart muscle to deteriorate. Differences in the molecular signals that initiate dilatation and concentric hypertrophy can explain why many drugs that improve prognosis in SHF have little if any benefit in DHF.


Assuntos
Insuficiência Cardíaca Diastólica/fisiopatologia , Insuficiência Cardíaca Sistólica/fisiopatologia , Cardiomiopatia Dilatada/etiologia , Proteínas do Citoesqueleto/fisiologia , Insuficiência Cardíaca Diastólica/etiologia , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Sistólica/etiologia , Insuficiência Cardíaca Sistólica/patologia , Ventrículos do Coração/patologia , Humanos , Transdução de Sinais/fisiologia , Estresse Fisiológico/fisiologia , Volume Sistólico/fisiologia , Disfunção Ventricular/patologia , Disfunção Ventricular/fisiopatologia
16.
PLoS One ; 10(10): e0139715, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26461521

RESUMO

AIM: Cardiac inflammation is important in the pathogenesis of heart failure. However, the consequence of systemic inflammation on concomitant established heart failure, and in particular diastolic heart failure, is less explored. Here we investigated the impact of systemic inflammation, caused by sustained Toll-like receptor 9 activation, on established diastolic heart failure. METHODS AND RESULTS: Diastolic heart failure was established in 8-10 week old cardiomyocyte specific, inducible SERCA2a knock out (i.e., SERCA2a KO) C57Bl/6J mice. Four weeks after conditional KO, mice were randomized to receive Toll-like receptor 9 agonist (CpG B; 2µg/g body weight) or PBS every third day. After additional four weeks, echocardiography, phase contrast magnetic resonance imaging, histology, flow cytometry, and cardiac RNA analyses were performed. A subgroup was followed, registering morbidity and death. Non-heart failure control groups treated with CpG B or PBS served as controls. Our main findings were: (i) Toll-like receptor 9 activation (CpG B) reduced life expectancy in SERCA2a KO mice compared to PBS treated SERCA2a KO mice. (ii) Diastolic function was lower in SERCA2a KO mice with Toll-like receptor 9 activation. (iii) Toll-like receptor 9 stimulated SERCA2a KO mice also had increased cardiac and systemic inflammation. CONCLUSION: Sustained activation of Toll-like receptor 9 causes cardiac and systemic inflammation, and deterioration of SERCA2a depletion-mediated diastolic heart failure.


Assuntos
Insuficiência Cardíaca Diastólica/patologia , Inflamação/patologia , Miocárdio/enzimologia , Miocárdio/patologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/deficiência , Receptor Toll-Like 9/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Diástole , Fibrose , Regulação da Expressão Gênica , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/metabolismo , Insuficiência Cardíaca Diastólica/fisiopatologia , Hidroxiprolina/metabolismo , Inflamação/complicações , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mortalidade Prematura , Tamanho do Órgão , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Ultrassonografia
17.
Int J Cardiol ; 184: 466-472, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25756566

RESUMO

AIMS: To examine whether increasing fasting plasma glucose (FPG) levels were associated with worsening left ventricular (LV) diastolic function, independently of LV mass index (LVMI) in elderly, otherwise healthy subjects. METHODS AND RESULTS: We tested cross-sectional associations between echocardiographically determined averaged E/é ratio/diastolic function, LVMI, cardiovascular risk factors, and FPG categorized as normal (NFG), impaired (IFG), and new-onset diabetes mellitus (DM), in 483 men and 208 women aged 56-79 years without overt cardiovascular disease, who received no cardiovascular, anti-diabetic, or lipid-lowering drugs and had a preserved LV ejection fraction >50%. Median E/é was significantly higher among subjects with diabetes than those without (8 vs. 7; p = 0.03), as was the prevalence of grade 2 or 3 diastolic dysfunction (25% vs. 16%; p = 0.02). E/é and diastolic function were significantly associated with LVMI (p ≤ 0.002), but not FPG category, on multivariable analysis. However, interaction analyses revealed that increasing LVMI was primarily associated with worsening diastolic function (higher E/é) in subjects with FPG > 6 mmol/L (ß=0.005 for IFG and DM vs. 0.001 for NFG; p = 0.02), whereas increasing systolic blood pressure was primarily associated with worsening diastolic function (higher E/é) in subjects with FPG ≤ 6.9 mmol/L (ß = 0.005 for NFG and 0.003 for IFG vs. -0.001 for DM; p=0.001). CONCLUSION: Diastolic dysfunction was significantly more prevalent among patients with DM than those without. The importance of LVMI increased, but the importance of systolic blood pressure decreased with higher FPG category.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca Diastólica , Hipertrofia Ventricular Esquerda , Disfunção Ventricular Esquerda , Fatores Etários , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Ecocardiografia/métodos , Jejum/sangue , Feminino , Avaliação Geriátrica/métodos , Insuficiência Cardíaca Diastólica/sangue , Insuficiência Cardíaca Diastólica/epidemiologia , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Esquerda/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estatística como Assunto , Suécia/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/epidemiologia
18.
Vopr Pitan ; 84(4): 37-46, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26852530

RESUMO

In open prospective monocentric study in 3 parallel groups we studied the effectiveness of correction of body composition using low calorie diet therapy with inclusion of specialized food products (SFP)--sources of polyphenols and iridoids made on the basis of the juice of Morinda citrifolia L. fruits. We studied 90 patients aged from 30 to 50 years old with grade III obesity and clinically expressed secondary diastolic heart failure. The duration of diet therapy was 42 days. It was shown that low-calorie diet has non-optimal effect on the body composition in morbidly obese patients with secondary diastolic heart failure, namely leading to the expressed loss of body fatless (7.2%, p=0.00008) and muscle mass (by 16.6%, p=0.00004); at the same time the reduction of total body weight is noted only by 2.3% (p=0.053), reduction of waist measurement by 1.3% (p=0.028) and reduction of hips measurement by 1.3% (p=0.09), accompanied by the reduction of body fat by 8.5% (p=0.000017) and of liquid by 7.3% (p=0.0018). The introduction of the SFP into the diet optimizes the effect of low calorie diet therapy on the anthropometric parameters and body composition. The most important effect of the SFP is the ability to prevent the excess loss of muscle mass in patients, and this effect is being dose-dependent. The loss of muscle mass in two groups of patients was 3.1-4.1% after 6 weeks of diet therapy, while in the control group it was 8.5% (p=0.0051). We have concluded that the inclusion of the SFP, manufactured on the basis Morinda citrifolia L. (noni) juice to the low calorie diet allows to initiate mainly the loss of the body fat with the simultaneous protection of active cellular mass, which is without doubt can be considered as the advantage compared to the standard low calorie diet.


Assuntos
Adiposidade , Restrição Calórica/métodos , Insuficiência Cardíaca Diastólica , Obesidade , Adulto , Feminino , Insuficiência Cardíaca Diastólica/dietoterapia , Insuficiência Cardíaca Diastólica/etiologia , Insuficiência Cardíaca Diastólica/patologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/dietoterapia , Obesidade/patologia , Obesidade/fisiopatologia , Estudos Prospectivos
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