Raffaella D’Alessandro

Mitochondrial diseases and the heart: an overview of molecular basis, diagnosis, treatment and clinical course

The mitochondrion is the main site of production of ATP that represents the source of energy for a large number of cellular processes. Mitochondrial diseases that result in a deficit in ATP production can affect almost every organ system with a large spectrum of clinical phenotypes. Cardiomyocytes are particularly vulnerable to limited ATP supply because of their large energy requirement. Abnormalities in the mitochondrial function are increasingly recognized in association with dilated and hypertrophic cardiomyopathy, cardiac conduction defects, endothelial dysfunction and coronary artery disease. Cardiologists should, therefore, be alerted to symptoms and signs suggestive of mitochondrial diseases and become familiar with the general issues related to multisystem disease management, genetic counseling and testing.

Takotsubo Cardiomyopathy Do the Genetics Matter

Takotsubo cardiomyopathy (TTC) is an enigmatic disease with a multifactorial and still unresolved pathogenesis. Recent experimental and clinical observation has suggested a role for genetics in the pathogenesis of TTC. Ethnic as well as seasonal variation in the prevalence of TTC is well described, but it is only recently that familial cases of TTC have been reported. In recent years technological advances in exome capture and DNA sequencing have offered clinicians a new opportunity to discover genetics-related disease. This article explores the role of genetic mechanisms that might explain or modulate the pathogenesis of TTC.

Cardiotrophin-1 and TNF-α circulating levels at rest and during cardiopulmonary exercise test in athletes and healthy individuals

BACKGROUND There is a growing body of evidence that physical training exerts its potential benefits on the individual health status by modulating the immune system and the whole body metabolism. A better knowledge of the physiologic immune response to exercise may help to understand the benefits of physical exercise in healthy individuals and elite athletes. AIMS This study aims to analyse cardiotrophin-1 (CT-1) and Tumor Necrosis Factor-alpha (TNF-alpha) plasma levels at rest and during exercise in elite athletes and healthy controls. METHODS We studied 20 triathletes (TA) and 20 matched controls (CG). Chambers dimensions, left ventricular mass and left ventricular mass index were analysed by echocardiography. VO2 peak and VE/VCO2 were calculated by metabolic stress test. Blood samples were collected before the exercise session, at the exercise peak, and after the end of exercise. ELISA assays were used to measure CT-1 and TNF-alpha plasma levels. RESULTS Among TA and CG, no significant differences were found for CT-1 (0.25+/-0.14 vs 0.20+/-0.14 fm/l; p=0.29) and TNF-alpha (10.8+/-2.7 vs 9.7+/-4.0 pm/l; p=0.29) basal levels. In the TA, plasma levels of CT-1 were significantly different at rest and during exercise (basal 0.25+/-0.13 pm/l; peak 1.07+/-1.5 pm/l; post-exercise 0.67+/-0.77 pm/l; p=0.04). Conversely, no significant differences were found between basal, peak and post-exercise plasma values of TNF-alpha (basal 10.8+/-2.7 pm/l; peak 11.7+/-2.1 pm/l; post-exercise 11.4+/-2.5 pm/l; p=0.78) in TA. CONCLUSIONS This study gives novel insights on the behavior of inflammatory cytokines during physical exercise in athletes and healthy individuals.

Natriuretic peptides: molecular biology, pathophysiology and clinical implications for the cardiologist

Natriuretic peptides (NPs) counter the effects of volume overload or adrenergic activation of the cardiovascular system. They are able to induce arterial vasodilatations, natriuresis and diuresis, and they reduce the activities of the renin-angiotensin-aldosterone system and the sympathetic nervous system. However, in addition to wall stress, other factors have been associated with elevated natriuretic peptide levels. Since 2000, because of their characteristics, NPs have become quantitative plasma biomarkers of heart failure. Nowadays, NPs play an important role not only in the diagnosis of heart failure, but also for a prognostic purpose and a guide to medical therapy. Finally, a new drug that modulates the NP system or recombinant analogs of NPs are now available in patients with heart failure.