RESUMO
Factors that compete to establish heart failure (HF) are not completely known. In the last years the several technological improvements allowed us to deeply study the molecular and genetic aspects of this complex syndrome. This new approach to HF based on molecular biology new discoveries shows us more clearly the pathophysiological bases of this disease, and a future scenery where the genetics may be useful in the clinical practice, as screening of high risk populations, as well as in the diagnosis and therapy of underlying myocardial diseases. The purpose of this review was to analyse the molecular, genetic and epigenetic factors of HF. We described the molecular anatomy of the sarcomere and the pathogenesis of the heart muscle diseases, abandoning the previous monogenic theory for the concept of a polygenic disease. Different actors play a role to cause the illness by themselves, modifying the expression of the disease and, eventually, the prognosis of the patient.
Assuntos
Epigenômica , Insuficiência Cardíaca/genética , Desmossomos/genética , Regulação da Expressão Gênica , Interação Gene-Ambiente , Humanos , Mutação , Contração MiocárdicaRESUMO
Cardiotrophin-1 (CT-1), a member of interleukin (IL)-6 family, was originally isolated for its ability to induce a hypertrophic response in neonatal cardiac myocytes. This cytokine mediates a pleiotropic set of growth and differentiation activities through a unique receptor system, consisting of IL-6 receptor (IL-6R) and a common signal transducer, the glycoprotein 130 (gp130). Both in humans and in mice, CT-1 mRNA has been detected in several tissues, such as liver tissue, adipose tissue, and tissues in the respiratory and nervous systems; in each of these tissues it performs different functions. Predominant actions of CT-1 are on the heart, where it is synthesized and where it provides first myocardial protection by promoting cell survival and proliferation, it carries on its haemodynamic effects and endocrine properties, and finally, it predisposes the heart to pathological conditions. The aim of this review is to describe the pathophysiological mechanisms through which CT-1 carries out its activities, especially on the heart, and its potential contribution as a disease marker in clinical cardiology. Recent studies have confirmed its active role in promoting structural changes typical of most common cardiovascular disease, such as hypertension, valve diseases, congestive heart failure, and coronary artery disease. In fact, CT-1 induces myocyte hypertrophy and collagen synthesis, thereby participating in the progression of ventricular remodelling, which results in cardiac muscle failure at the latest stage. CT-1 plasma levels are elevated in patients with hypertension and coronary artery diseases, and they are also correlated with the severity of valve diseases and heart failure. Therefore, CT-1 may represent a diagnostic, staging, and prognostic biomarker of cardiovascular diseases.
Assuntos
Doenças Cardiovasculares/metabolismo , Citocinas/metabolismo , Citocinas/fisiologia , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Citocinas/genética , Humanos , Modelos Biológicos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologiaRESUMO
Over the last decades, there has been a significant increase in incidence and prevalence of heart failure, a major cause of cardiac morbidity and mortality. Measurements of neurohormones, in particular B-type natriuretic peptide (BNP), can significantly improve diagnostic accuracy, and also correlate with long-term morbidity and mortality in patients with chronic heart failure presenting to the emergency department. BNP is secreted by cardiac ventricles mainly in response to wall stress and neurohormonal factors like the sympathetic nervous system, endothelins, and the rennin-angiotensin-aldosterone system. BNP increases myocardial relaxation and oppose the vasoconstrictive, sodium retaining, and natriuretic effects caused by vasoconstrictive factors. BNP is the first biomarker to prove its clinical value for the diagnosis of left ventricular systolic and diastolic dysfunction but also for the right ventricular dysfunction, guiding prognosis and therapy management. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.