RESUMO
Amyloid deposition within stenotic aortic valves (AVs) also appears frequent in the absence of cardiac amyloidosis, but its clinical and pathophysiological relevance has not been investigated. We will elucidate the rate of isolated AV amyloid deposition and its potential clinical and pathophysiological significance in aortic stenosis (AS). In 130 patients without systemic and/or cardiac amyloidosis, we collected the explanted AVs during cardiac surgery: 57 patients with calcific AS and 73 patients with AV insufficiency (41 with AV sclerosis and 32 without, who were used as controls). Amyloid deposition was found in 21 AS valves (37%), 4 sclerotic AVs (10%), and none of the controls. Patients with and without isolated AV amyloid deposition had similar clinical and echocardiographic characteristics and survival rates. Isolated AV amyloid deposition was associated with higher degrees of AV fibrosis (p = 0.0082) and calcification (p < 0.0001). Immunohistochemistry analysis suggested serum amyloid A1 (SAA1), in addition to transthyretin (TTR), as the protein possibly involved in AV amyloid deposition. Circulating SAA1 levels were within the normal range in all groups, and no difference was observed in AS patients with and without AV amyloid deposition. In vitro, AV interstitial cells (VICs) were stimulated with interleukin (IL)-1ß which induced increased SAA1-mRNA both in the control VICs (+6.4 ± 0.5, p = 0.02) and the AS VICs (+7.6 ± 0.5, p = 0.008). In conclusion, isolated AV amyloid deposition is frequent in the context of AS, but it does not appear to have potential clinical relevance. Conversely, amyloid deposition within AV leaflets, probably promoted by local inflammation, could play a role in AS pathophysiology.
Assuntos
Amiloidose , Estenose da Valva Aórtica , Calcinose , Humanos , Catéteres , Calcificação Fisiológica , Interleucina-1betaRESUMO
BACKGROUND: Epicardial adipose tissue (EAT) plays an important role in cardiometabolic risk. EAT is a modifiable risk factor and could be a potential therapeutic target for drugs that already show cardiovascular benefits. The aim of this study is to evaluate the effect of cardiometabolic drugs on EAT reduction. METHODS: A detailed search related to the effect on EAT reduction due to cardiometabolic drugs, such as glucagon-like peptide-1 receptor agonist (GLP-1 RA), sodium-glucose cotransporter-2 inhibitors (SGLT2-i), and statins was conducted according to PRISMA guidelines. Eighteen studies enrolling 1064 patients were included in the qualitative and quantitative analyses. RESULTS: All three analyzed drug classes, in particular GLP-1 RA, show a significant effect on EAT reduction (GLP-1 RA standardize mean difference (SMD) = - 1.005; p < 0.001; SGLT2-i SMD = - 0.552; p < 0.001, and statin SMD = - 0.195; p < 0.001). The sensitivity analysis showed that cardiometabolic drugs strongly benefit EAT thickness reduction, measured by ultrasound (overall SMD of - 0.663; 95%CI - 0.79, - 0.52; p < 0.001). Meta-regression analysis revealed younger age and higher BMI as significant effect modifiers of the association between cardiometabolic drugs and EAT reduction for both composite effect and effect on EAT thickness, (age Z: 3.99; p < 0.001 and Z: 1.97; p = 0.001, respectively; BMI Z: - 4.40; p < 0.001 and Z: - 2.85; p = 0.004, respectively). CONCLUSIONS: Cardiometabolic drugs show a significant beneficial effect on EAT reduction. GLP-1 RA was more effective than SGLT2-i, while statins had a rather mild effect. We believe that the most effective treatment with these drugs should target younger patients with high BMI.
Assuntos
Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Peptídeo 1 Semelhante ao Glucagon , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Obesidade , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêuticoRESUMO
Although in heart failure (HF) there is a strict correlation between heart and kidney, no data are available on the potential relationship in HF between renal dysfunction (RD) and the impaired sympathetic innervation. Aim of the present study was to assess the relationship between RD and cardiac sympathetic innervation in HF patients with reduced ejection fraction. Two hundred and sixty-three patients with mild-to-severe HF underwent iodine-123 meta-iodobenzylguanidine myocardial scintigraphy to assess sympathetic innervation, evaluating early and late heart-to-mediastinum (H/M) ratios and washout rate. In all patients, glomerular filtration rate (eGFR) by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula was assessed. A direct association was found between EPI-eGFR and late H/M (r = .215; P < .001). Dividing the population into moderate-to-severe eGFR reduction and normal-to-mildly reduced eGFR (cutoff ≤ 60 mL·min-1·1.73 m-2), a statistically significant reduction of late H/M value was found in patients with RD compared to patients with preserved eGFR (P = .030). By multivariable linear regression analysis, eGFR resulted in the prediction of impaired late H/M in patients with RD (P = .005). Patients with RD and HF show more impaired cardiac sympathetic activity than HF patients with preserved renal function, and reduced eGFR is a predictor of reduced late H/M.
Assuntos
Adrenérgicos/metabolismo , Insuficiência Cardíaca/complicações , Nefropatias/etiologia , Idoso , Feminino , Coração/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Itália , Rim/fisiopatologia , Nefropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estatísticas não ParamétricasRESUMO
Given the epidemiologic increase of aged population in the world, aortic stenosis (AS) represents now the most common valvular heart disease in industrialized countries. It is a very challenging disease, representing an important cause of morbidity, hospitalization and death in the elderly population. It is widely recognized that AS is the result of a very complex active process, driven by inflammation and involving multifactorial pathological mechanisms promoting valvular calcification and valvular bone deposition. Several evidence suggest that epicardial adipose tissue (EAT), the visceral fat depot of the heart, represents a direct source of cytokines and could mediate the deleterious effects of systemic inflammation on the myocardium. Importantly, obesity and metabolic disorders are associated with chronic systemic inflammation leading to a significant increase of EAT amount and to a pro-inflammatory phenotypic shift of this fat depot. It has been hypothesized that the EAT inflammatory state can influence the structure and function of the heart, thus contributing to the pathogenesis of several cardiac diseases, including calcific AS. The current review will discuss the recently discovered mechanisms involved in the pathogenesis of AS, with particular attention to the role of inflammation, metabolic risk factors and pro-fibrotic and pro-osteogenic signal pathways promoting the onset and progression of the disease. Moreover, it will be explored the potential role of EAT in the AS pathophysiology.
Assuntos
Estenose da Valva Aórtica , Calcinose , Idoso , Valva Aórtica , Humanos , Inflamação , Fatores de RiscoRESUMO
BACKGROUND AND AIM: Echocardiography is a promising technique for the assessment of epicardial adipose tissue (EAT). Increased EAT thickness is associated with different cardiac diseases, including; coronary artery disease (CAD). Since several different echocardiographic approaches have been proposed to measure EAT, the identification of a standardized method is needed. We propose the assessment of EAT maximal thickness at the Rindfleisch fold, the reproducibility of this measurement and its correlation with EAT thickness and volume assessed at cardiac magnetic resonance (CMR). Finally, we will test the predictive role of this measurement on the presence of significant CAD. METHODS AND RESULTS: In 1061 patients undergoing echocardiography, EAT thickness was measured at the level of the Rindfleisch fold. In 70 patients, we tested the relationship between echo-EAT thickness and EAT thickness and volume assessed at CMR. In 499 patients with suspected CAD, undergoing coronary artery angiography, we tested the predictive value of EAT on the presence of significant CAD. Echo-EAT thickness measurements had an excellent reliability as indicated by the inter-observer (ICC:0.97; 95% C.I. 0.96 to 0.98) and intra-observer (ICC:0.99; 95% C.I. 0.98 to 0.99) reliability rates. Echo-EAT thickness significantly correlated with CMR-EAT thickness and volume (p < 0.001). An EAT thickness value >10 mm discriminated patients with significant CAD at coronary angiography (p < 0.001). At multivariable analysis, including demographic data and cardiovascular risk factors, EAT thickness was an independent predictor of significant CAD and showed an additive predictive value over common atherosclerotic risk factors. CONCLUSIONS: Echocardiographic assessment of EAT thickness at the level of the Rindfleisch fold represents a simple and trustworthy method. An increased EAT thickness shows an additive predictive value on CAD over common atherosclerotic risk factors, thus suggesting its potential clinical use for CAD risk stratification.
Assuntos
Tecido Adiposo/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia , Pericárdio/diagnóstico por imagem , Adulto , Idoso , Angiografia Coronária , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Heart failure (HF) is often managed by geriatricians. Few data are available on their knowledge and attitudes about this condition. AIMS: To compare perceptions and knowledge on HF of specialists/fellows in geriatrics working in Italy. METHODS: This nation-wide survey carried out by the Italian Society of Gerontology and Geriatrics in May-June 2019 enrolled 283 specialists/fellows in geriatrics in Italy. Results were stratified by qualification (specialist/fellow) and performance (lower/higher quartile of correct answers). RESULTS: About half (55.5%) of the participants worked in acute care wards, 190 were residents, and 93 specialists. The overall proportion of correct answers was 70.8%, with no differences between specialists and fellows. There was a poor knowledge, with no differences between groups, about the target doses of ACE-inhibitors (36% of correct answers), the pharmacological treatment of HF with preserved ejection fraction (HFpEF) (37% of correct answers), and the inotropes indicated in acute HF (35% of correct answers). Compared to specialists, fellows performed better on indication (88% vs 76%, P = 0.019) and mechanism of action (93% vs 84%, P = 0.023) of sacubitril/valsartan, and on therapeutic indications of patients with atrial fibrillation (92% vs 75%, P < 0.001). CONCLUSIONS: Globally, there was a good knowledge of the latest guidelines on the diagnosis and management of HF. However, for some important topics, such as HFpEF, that is the most common HF manifestation in older adults, the observed performance was relatively poor, indicating the need for focused educational campaigns.
Assuntos
Geriatria , Insuficiência Cardíaca , Idoso , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Itália , Especialização , Volume Sistólico , Inquéritos e QuestionáriosRESUMO
Diabetes mellitus (DM) and heart failure (HF) are frequent comorbidities among elderly patients. HF, a leading cause of mortality and morbidity worldwide, is characterized by sympathetic nervous system hyperactivity. The prevalence of diabetes mellitus (DM) is rapidly growing and the risk of developing HF is higher among DM patients. DM is responsible for several macro- and micro-angiopathies that contribute to the development of coronary artery disease (CAD), peripheral artery disease, retinopathy, neuropathy and diabetic nephropathy (DN) as well. Independently of CAD, chronic kidney disease (CKD) and DM increase the risk of HF. Individuals with diabetic nephropathy are likely to present a distinct pathological condition, defined as diabetic cardiomyopathy, even in the absence of hypertension or CAD, whose pathogenesis is only partially known. However, several hypotheses have been proposed to explain the mechanism of diabetic cardiomyopathy: increased oxidative stress, altered substrate metabolism, mitochondrial dysfunction, activation of renin-angiotensin-aldosterone system (RAAS), insulin resistance, and autonomic dysfunction. In this review, we will focus on the involvement of sympathetic system hyperactivity in the diabetic nephropathy.
Assuntos
Cardiomiopatias Diabéticas/etiologia , Nefropatias Diabéticas/complicações , Insuficiência Cardíaca/etiologia , Sistema Nervoso Simpático/fisiopatologia , HumanosRESUMO
Despite improvements in management and therapeutic approach in the last decades, heart failure is still associated with high mortality rates. The sustained enhancement in the sympathetic nervous system tone, observed in patients with heart failure, causes alteration in ß-adrenergic receptor signaling and function. This latter phenomenon is the result of several heart failure-related molecular abnormalities involving adrenergic receptors, G-protein-coupled receptor kinases, and ß-arrestins. This article summarizes novel encouraging preclinical strategies to reactivate ß-adrenergic receptor signaling in heart failure, including pharmacologic and gene therapy approaches, and attempts to translate acquired notions into the clinical setting.
Assuntos
Insuficiência Cardíaca/genética , Polimorfismo Genético , Receptores Adrenérgicos beta/genética , Insuficiência Cardíaca/metabolismo , Humanos , Receptores Adrenérgicos beta/metabolismo , Transdução de SinaisRESUMO
RATIONALE: Sympathetic nervous system hyperactivity is associated with poor prognosis in patients with heart failure (HF), yet routine assessment of sympathetic nervous system activation is not recommended for clinical practice. Myocardial G protein-coupled receptor kinase-2 (GRK2) is upregulated in HF patients, causing dysfunctional ß-adrenergic receptor signaling. Importantly, myocardial GRK2 levels correlate with levels found in peripheral lymphocytes of HF patients. OBJECTIVE: The independent prognostic value of blood GRK2 measurements in HF patients has never been investigated; thus, the purpose of this study was to evaluate whether lymphocyte GRK2 levels predict clinical outcome in HF patients. METHODS AND RESULTS: We prospectively studied 257 HF patients with mean left ventricular ejection fraction of 31.4±8.5%. At the time of enrollment, plasma norepinephrine, serum NT-proBNP, and lymphocyte GRK2 levels, as well as clinical and instrumental variables were measured. The prognostic value of GRK2 to predict cardiovascular (CV) death and all-cause mortality was assessed using the Cox proportional hazard model including demographic, clinical, instrumental, and laboratory data. Over a mean follow-up period of 37.5±20.2 months (range, 3-60 months), there were 102 CV deaths. Age, left ventricular ejection fraction, New York Heart Association class, chronic obstructive pulmonary disease, chronic kidney disease, N-terminal-pro brain natriuretic peptide, and lymphocyte GRK2 protein levels were independent predictors of CV mortality in HF patients. GRK2 levels showed an additional prognostic and clinical value over demographic and clinical variables. The independent prognostic value of lymphocyte GRK2 levels was also confirmed for all-cause mortality. CONCLUSIONS: Lymphocyte GRK2 protein levels can independently predict prognosis in patients with HF.
Assuntos
Quinase 2 de Receptor Acoplado a Proteína G/sangue , Insuficiência Cardíaca/sangue , Linfócitos/enzimologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Doenças Cardiovasculares/mortalidade , Causas de Morte , Feminino , Seguimentos , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Mortalidade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Volume Sistólico , Sistema Nervoso Simpático/fisiopatologia , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/enzimologia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
RATIONALE: It has been reported that epicardial adipose tissue (EAT) may affect myocardial autonomic function. OBJECTIVE: The aim of this study was to explore the relationship between EAT and cardiac sympathetic nerve activity in patients with heart failure. METHODS AND RESULTS: In 110 patients with systolic heart failure, we evaluated the correlation between echocardiographic EAT thickness and cardiac adrenergic nerve activity assessed by (123)I-metaiodobenzylguanidine ((123)I-MIBG). The predictive value of EAT thickness on cardiac sympathetic denervation ((123)I-MIBG early and late heart:mediastinum ratio and single-photon emission computed tomography total defect score) was tested in a multivariate analysis. Furthermore, catecholamine levels, catecholamine biosynthetic enzymes, and sympathetic nerve fibers were measured in EAT and subcutaneous adipose tissue biopsies obtained from patients with heart failure who underwent cardiac surgery. EAT thickness correlated with (123)I-MIBG early and late heart:mediastinum ratio and single-photon emission computed tomography total defect score, but not with left ventricular ejection fraction. Moreover, EAT resulted as an independent predictor of (123)I-MIBG early and late heart:mediastinum ratio and single-photon emission computed tomography total defect score and showed a significant additive predictive value on (123)I-MIBG planar and single-photon emission computed tomography results over demographic and clinical data. Although no differences were found in sympathetic innervation between EAT and subcutaneous adipose tissue, EAT showed an enhanced adrenergic activity demonstrated by the increased catecholamine levels and expression of catecholamine biosynthetic enzymes. CONCLUSIONS: This study provides the first evidence of a direct correlation between increased EAT thickness and cardiac sympathetic denervation in heart failure.
Assuntos
Tecido Adiposo/inervação , Fibras Adrenérgicas/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Pericárdio/inervação , Tecido Adiposo/diagnóstico por imagem , Idoso , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pericárdio/diagnóstico por imagemRESUMO
After hindlimb ischemia (HI), increased catecholamine levels within the ischemic muscle can cause dysregulation of ß2-adrenergic receptor (ß2AR) signaling, leading to reduced revascularization. Indeed, in vivo ß2AR overexpression via gene therapy enhances angiogenesis in a rat model of HI. G protein-coupled receptor kinase 2 (GRK2) is a key regulator of ßAR signaling, and ß adrenergic receptor kinase C-terminal peptide (ßARKct), a peptide inhibitor of GRK2, has been shown to prevent ßAR down-regulation and to protect cardiac myocytes and stem cells from ischemic injury through restoration of ß2AR protective signaling (i.e., protein kinase B/endothelial nitric oxide synthase). Herein, we tested the potential therapeutic effects of adenoviral-mediated ßARKct gene transfer in an experimental model of HI and its effects on ßAR signaling and on endothelial cell (EC) function in vitro. Accordingly, in this study, we surgically induced HI in rats by femoral artery resection (FAR). Fifteen days of ischemia resulted in significant ßAR down-regulation that was paralleled by an approximately 2-fold increase in GRK2 levels in the ischemic muscle. Importantly, in vivo gene transfer of the ßARKct in the hindlimb of rats at the time of FAR resulted in a marked improvement of hindlimb perfusion, with increased capillary and ßAR density in the ischemic muscle, compared with control groups. The effect of ßARKct expression was also assessed in vitro in cultured ECs. Interestingly, ECs expressing the ßARKct fenoterol, a ß2AR-agonist, induced enhanced ß2AR proangiogenic signaling and increased EC function. Our results suggest that ßARKct gene therapy and subsequent GRK2 inhibition promotes angiogenesis in a model of HI by preventing ischemia-induced ß2AR down-regulation.
Assuntos
Terapia Genética/tendências , Membro Posterior/irrigação sanguínea , Isquemia/genética , Neovascularização Patológica/genética , Receptores Adrenérgicos beta 2/genética , Quinases de Receptores Adrenérgicos beta/genética , Animais , Bovinos , Células Cultivadas , Isquemia/terapia , Masculino , Neovascularização Patológica/terapia , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/genética , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2/metabolismo , Quinases de Receptores Adrenérgicos beta/administração & dosagemRESUMO
PURPOSE: Sympathetic nervous system (SNS) hyperactivity is a salient characteristic of chronic heart failure (HF) and contributes to the progression of the disease. Iodine-123 meta-iodobenzylguanidine (123I-mIBG) imaging has been successfully used to assess cardiac SNS activity in HF patients and to predict prognosis. Importantly, SNS hyperactivity characterizes also physiological ageing, and there is conflicting evidence on cardiac 123I-mIBG uptake in healthy elderly subjects compared to adults. However, little data are available on the impact of ageing on cardiac sympathetic nerve activity assessed by 123I-mIBG scintigraphy, in patients with HF. METHODS AND RESULTS: We studied 180 HF patients (age = 66.1 ± 10.5 years [yrs]), left ventricular ejection fraction (LVEF = 30.6 ± 6.3 %) undergoing cardiac 123I-mIBG imaging. Early and late heart to mediastinum (H/M) ratios and washout rate were calculated in all patients. Demographic, clinical, and echocardiographic data were also collected. Our study population consisted of 53 patients aged >75 years (age = 77.7 ± 4.0 year), 67 patients aged 62-72 years (age = 67.9 ± 3.2 years) and 60 patients aged ≤61 year (age = 53.9 ± 5.6 years). In elderly patients, both early and late H/M ratios were significantly lower compared to younger patients (p < 0.05). By multivariate analysis, H/M ratios (both early and late) and washout rate were significantly correlated with LVEF and age. CONCLUSIONS: Our data indicate that, in a population of HF patients, there is an independent age-related effect on cardiac SNS innervation assessed by 123I-mIBG imaging. This finding suggests that cardiac 123I-mIBG uptake in patients with HF might be affected by patient age.
Assuntos
3-Iodobenzilguanidina , Envelhecimento , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Sistema Nervoso Simpático/diagnóstico por imagem , Sistema Nervoso Simpático/fisiopatologia , Idoso , Técnicas de Imagem Cardíaca/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/métodosRESUMO
BACKGROUND: Diabetes mellitus (DM) is associated with impaired prognosis in patients with heart failure (HF), but pathogenic mechanisms are unclear. In the failing heart, elevated ß-adrenergic receptor (ß-AR) activation by catecholamines causes G-protein-coupled receptor kinase-2 (GRK2) upregulation which is responsible for ß-AR signalling dysfunction. Importantly, GRK2 expression, measured in peripheral lymphocytes of HF patients, correlates with levels of this kinase in the failing myocardium reflecting the loss of hemodynamic function. Moreover, HF-related GRK2 protein overexpression promotes insulin resistance by interfering with insulin signalling. The aim of this study was to assess lymphocyte GRK2 protein levels in HF patients with and without DM. METHODS AND MATERIALS: Patients with a diagnosis of HF were enrolled in the study. All subjects underwent a complete clinical examination (including NYHA functional class assessment and echocardiography) and blood draw for serum N-terminal pro-brain natriuretic peptide (NT-proBNP), lymphocyte GRK2 and plasma norepinephrine (NE) levels. Demographic data including age, sex, medications, cardiovascular risk factors and presence of comorbidities were also collected. RESULTS: Two hundred and sixty-eight patients with HF (left ventricular ejection fraction [LVEF] 30.6 ± 7.6%) with and without DM were enrolled. No differences between the two groups were found in terms of demography, HF aetiology, LVEF, NYHA class, NE and NT-proBNP. GRK2 was significantly higher in patients with DM compared to non-DM. At multivariate linear regression analysis, LVEF, NE, NT-proBNP and diabetes came out to be independent predictors of GRK2 levels in the overall study population. CONCLUSION: In HF patients, DM is associated with significantly more elevated lymphocyte GRK2 protein levels, likely reflecting more compromised cardiac ß-AR signalling/function, despite similar hemodynamic status and neuro-hormonal activation compared to patients without DM. These findings contribute to explain the negative prognostic impact of DM in patients with HF.
Assuntos
Angiopatias Diabéticas/metabolismo , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Insuficiência Cardíaca/metabolismo , Linfócitos/metabolismo , Idoso , Feminino , Humanos , Masculino , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismoRESUMO
PURPOSE: Myocardial contractile function is under the control of cardiac sympathetic activity. Three-dimensional speckle tracking echocardiography (3D-STE) and cardiac imaging with (123)I-metaiodobenzylguanidine ((123)I-MIBG) are two sophisticated techniques for the assessment of left ventricular (LV) deformation and sympathetic innervation, respectively, which offer important prognostic information in patients with heart failure (HF). The purpose of this investigation was to explore, in patients with systolic HF, the relationship between LV deformation assessed by 3D-STE and cardiac sympathetic derangement evaluated by (123)I-MIBG imaging. METHODS: We prospectively studied 75 patients with systolic HF. All patients underwent a 3D-STE study (longitudinal, circumferential, area and radial) and (123)I-MIBG planar and SPECT cardiac imaging. RESULTS: 3D-STE longitudinal, circumferential and area strain values were correlated with (123)I-MIBG late heart to mediastinum (H/M) ratio and late SPECT total defect score. After stratification of the patients according to ischaemic or nonischaemic HF aetiology, we observed a good correlation of all 3D-STE measurements with late H/M ratio and SPECT data in the ischaemic group, but in patients with HF of nonischaemic aetiology, no correlation was found between LV deformation and cardiac sympathetic activity. At the regional level, the strongest correlation between LV deformation and adrenergic innervation was found for the left anterior descending coronary artery distribution territory for all four 3D-STE values. In multivariate linear regression analyses, including age, gender, LV ejection fraction, NYHA class, body mass index, heart rate and HF aetiology, only 3D-STE area and radial strain values significantly predicted cardiac sympathetic derangement on (123)I-MIBG late SPECT. CONCLUSION: This study indicated that 3D-STE measurements are correlated with (123)I-MIBG planar and SPECT data. Furthermore, 3D-STE area and radial strain values, but not LVEF, predict cardiac sympathetic derangement in human postischaemic HF.
Assuntos
3-Iodobenzilguanidina , Doenças do Sistema Nervoso Autônomo/diagnóstico , Ecocardiografia Tridimensional/métodos , Insuficiência Cardíaca/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Doenças do Sistema Nervoso Autônomo/etiologia , Feminino , Insuficiência Cardíaca/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/etiologiaRESUMO
BACKGROUND: The sphingosine-1-phosphate receptor 1 (S1PR1) and ß1-adrenergic receptor (ß1AR) are G-protein-coupled receptors expressed in the heart. These 2 receptors have opposing actions on adenylyl cyclase because of differential G-protein coupling. Importantly, both of these receptors can be regulated by the actions of G-protein-coupled receptor kinase-2, which triggers desensitization and downregulation processes. Although classic signaling paradigms suggest that simultaneous activation of ß1ARs and S1PR1s in a myocyte would simply result in opposing action on cAMP production, in this report we have uncovered a direct interaction between these 2 receptors, with regulatory involvement of G-protein-coupled receptor kinase-2. METHODS AND RESULTS: In HEK (human embryonic kidney) 293 cells overexpressing both ß1AR and S1PR1, we demonstrated that ß1AR downregulation can occur after stimulation with sphingosine-1-phosphate (an S1PR1 agonist), whereas S1PR1 downregulation can be triggered by isoproterenol (a ß-adrenergic receptor agonist) treatment. This cross talk between these 2 distinct G-protein-coupled receptors appears to have physiological significance, because they interact and show reciprocal regulation in mouse hearts undergoing chronic ß-adrenergic receptor stimulation and in a rat model of postischemic heart failure. CONCLUSIONS: We demonstrate that restoration of cardiac plasma membrane levels of S1PR1 produces beneficial effects that counterbalance the deleterious ß1AR overstimulation in heart failure.
Assuntos
Terapia Genética/métodos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Receptores Adrenérgicos beta 1/genética , Receptores de Lisoesfingolipídeo/genética , Animais , Cardiomegalia/fisiopatologia , Cardiomegalia/terapia , Modelos Animais de Doenças , Progressão da Doença , Regulação para Baixo/fisiologia , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mioblastos Cardíacos/citologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Ratos , Ratos Endogâmicos WKY , Receptor Cross-Talk/fisiologia , Receptores Adrenérgicos beta 1/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Receptores de Esfingosina-1-FosfatoRESUMO
RE-START is a multicenter, randomized, prospective, open, controlled trial aiming to evaluate the feasibility and the short- and medium-term effects of an early-start AET program on functional capacity, symptoms and neurohormonal activation in chronic heart failure (CHF) patients with recent acute hemodynamic decompensation. Study endpoints will be: 1) safety of and compliance to AET; 2) effects of AET on i) functional capacity, ii) patient-reported symptoms and iii) AET-induced changes in beta-adrenergic receptor signaling and circulating angiogenetic and inflammatory markers. Two-hundred patients, randomized 1:1 to training (TR) or control (C), will be enrolled. Inclusion criteria: 1) history of systolic CHF for at least 6 months, with ongoing acute decompensation with need of intravenous diuretic and/or vasodilator therapy; 2) proBNP > 1000 pg/mI at admission. Exclusion criteria: 1) ongoing cardiogenic shock; 2) need of intravenous inotropic therapy; 3) creatinine > 2.5 mg/dl at admission. After a 72-hour run-in period, TR will undergo the following 12-day early-start AET protocol: days 1-2: active/passive mobilization (2 sessions/day, each 30 minutes duration); days 3-4: as days 1-2 + unloaded bedside cycle ergometer (3 sessions/day, each 5-10 minutes duration); days 5-8: as days 1-2 + unloaded bedside cycle ergometer (3 sessions/day, each 15-20 minutes duration); days 9-12: as days 1-2 + bedside cycle ergometer at 10-20 W (3 sessions/day, each 15-20 minutes duration). During the same period, C will undergo the same activity protocol as in days 1-2 for TR. All patients will undergo a 6-min WT at day 1, 6, 12 and 30 and echocardiogram, patient-reported symptoms on 7-point Likert scale and measurement of lymphocyte G protein coupled receptor kinase, VEGF, angiopoietin, TNF alfa, IL-1, IL-6 and eNOS levels at day 1, 12 and 30.
Assuntos
Terapia por Exercício/métodos , Insuficiência Cardíaca/reabilitação , Doença Crônica , Estudos de Viabilidade , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica , Humanos , Sistema Nervoso Simpático/fisiopatologiaRESUMO
The human prothymosin alpha (PTα) gene encodes a 12.5 kDa highly acidic nuclear protein that is widely expressed in mammalian tissues including the heart and importantly, is detectable also in blood serum. During apoptosis or necrosis, PTα changes its nuclear localization and is able to exert an important cytoprotective effect. Since the role of PTα in the heart has never been evaluated, the aim of the present study was to investigate the effects of PTα on cardiomyocytes during ischemic injury. Our data show that seven after myocardial infarction (MI), PTα expression levels are significantly increased both in blood serum and in cardiac tissue, and notably we observe that PTα translocates from the nuclei to cytoplasm and plasma membrane of cardiomyocytes following MI. Furthermore, in vitro experiments in cardiomyocytes, confirm that after 6 h of simulated ischemia (SI), PTα protein levels are upregulated compared to normoxic cells. Importantly, treatment of cardiomyocytes with a recombinant PTα (rPTα), during SI results in a significant decrease in the apoptotic response and in a robust increase in cell survival. Moreover, these effects are accompanied to a significant preservation of the activated levels of the anti-apoptotic serine-threonine kinase Akt. Consistent with our in vitro observation, rPTα-treated MI mice exhibit a strong reduction in infarct size at 24 h, compared to the MI control group and at the molecular level, PTα treatment induces activation of Akt. The present study provides for the first time the demonstration that PTα offers cardioprotection against ischemic injury by an Akt-dependent mechanism.
Assuntos
Apoptose , Isquemia Miocárdica/patologia , Miócitos Cardíacos/citologia , Precursores de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Timosina/análogos & derivados , Animais , Hipóxia Celular , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Precursores de Proteínas/farmacologia , Timosina/metabolismo , Timosina/farmacologiaRESUMO
The purpose of this study was to clarify whether changes in cardiopulmonary haemodynamics induced by pharmacological therapy correlate with exercise capacity and clinical events in patients with pulmonary arterial hypertension. 16 randomised trials including 2353 patients, followed up for 16.4±10.6 weeks, measuring cardiopulmonary haemodynamics by right heart catheterisation and reporting clinical events were included. Meta-analysis and meta-regression analysis were performed to assess the effects of treatments on clinical events and the relationship between haemodynamic changes (pulmonary artery pressure, pulmonary vascular resistance, cardiac index and right atrial pressure) and clinical events. Treatments significantly reduced all-cause death (OR 0.5, 95% CI 0.3-0.7; p<0.01), hospitalisation for pulmonary arterial hypertension (OR 0.4, 95% CI 0.2-0.7; p<0.01), initiation of rescue therapy (OR 0.3, 95% CI 0.2-0.6; p<0.01) and the composite outcome (OR 0.3, 95% CI 0.3-0.5; p<0.01). No relationship was found between changes of haemodynamic parameters and clinical events, whereas changes of cardiac index and pulmonary vascular resistance significantly correlated with changes in the 6-min walking distance (r = 0.64, p = 0.03; r = -0.55, p = 0.04, respectively). In patients with pulmonary arterial hypertension, improvements of cardiopulmonary haemodynamics observed in randomised clinical trials correlate with exercise capacity changes but do not predict clinical events in a short-term follow-up.