Aldosterone and Myocardial Pathology

Aldosterone (Aldo) has been intensively studied for years since its isolation by Simpson and Tait in the 1950s. Interestingly, although most early research around Aldo's actions focused primarily on its interaction with the kidney, it was soon evident that this hormone is able to exert unexplained extra-renal effects, on various target organs including the heart. Importantly, over the course of the last decade a number of studies in pre-clinical models (in vitro and in vivo) and in humans have clearly demonstrated that Aldo, following the interaction with its receptor, the mineralocorticoid receptor (MR), is able to activate specific intracellular genomic and non-genomic pathways thus, regulating the homeostasis of the entire cardiovascular system. In this regard, Aldo has been shown to influence the function and growth of different type of cells including cardiomyocytes, fibroblasts and vascular cells (vascular smooth muscle cells and endothelial cells). Importantly, when present at high levels, Aldo have been associated with the onset of disparate cardiovascular disorders including heart failure (HF). For this reason, several pre-clinical study and clinical trials have been designed in order to test the effects of Aldo antagonism in HF patients. In this chapter, we will guide the readers through the current knowledge around Aldo activity in cardiovascular system and the relevant therapies acting in blocking the noxious Aldo/MR signaling pathway.