%0 Journal Article %T ROS and RNS Signaling in Heart Disorders: Could Antioxidant Treatment Be Successful? %A Igor Afanas'ev %J Oxidative Medicine and Cellular Longevity %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/293769 %X There is not too much success in the antioxidant treatment of heart deceases in humans. However a new approach is now developed that suggests that depending on their structures and concentrations antioxidants can exhibit much more complicated functions in many pathological disorders. It is now well established that physiological free radicals superoxide and nitric oxide together with their derivatives hydrogen peroxide and peroxynitrite (all are named reactive oxygen species (ROS) and reactive nitrogen species (RNS)) play a more important role in heart diseases through their signaling functions. Correspondingly this work is dedicated to the consideration of damaging signaling by ROS and RNS in various heart and vascular disorders: heart failure (congestive heart failure or CHF), left ventricular hypertrophy (LVH), coronary heart disease, cardiac arrhythmias, and so forth. It will be demonstrated that ROS overproduction (oxidative stress) is a main origin of the transformation of normal physiological signaling processes into the damaging ones. Furthermore the favorable effects of low/moderate oxidative stress through preconditioning mechanisms in ischemia/reperfusion will be considered. And in the last part we will discuss the possibility of efficient application of antioxidants and enzyme/gene inhibitors for the regulation of damaging ROS signaling in heart disorders. 1. Introduction Heart disease (cardiopathy) and cardiovascular diseases are a group of numerous pathological disorders such as heart failure (congestive heart failure or CHF), left ventricular hypertrophy (LVH), coronary heart disease, cardiac arrhythmias, and so forth, in which signaling processes of reactive oxygen and reactive nitrogen species (ROS and RNS) play an important (probably critical) role. Contemporary studies identified major sources of ROS and RNS productions: NADPH oxidases (Nox), xanthine oxidase, mitochondria, and nitric oxide synthases (NOS). As a rule, heart and cardiovascular diseases are characterized by ROS overproduction whereas the formation of major RNSs nitric oxide (a free radical) and peroxynitrite (diamagnetic molecule) can decrease or increase depending on the nature of heart injury. Free radicals are usually considered to be the damaging factors in various pathologies, but on the other hand ROS and RNS are important signaling species in many physiological and pathophysiological processes. For example the critical role of these species has been shown in preconditioning and other survival processes (see below). A major aim of this work is to consider the role %U http://www.hindawi.com/journals/omcl/2011/293769/