Aliskiren – A promising antioxidant agent beyond hypertension reduction

The renin-angiotensin-aldosterone system (RAAS) is a hormonal system that has a critical role in maintaining the normotensive state and electrolyte balance of the organism. The RAAS also has an important influence in the development of various pathophysiological conditions especially those concerning the renal system, cardiovascular system and hypertension. One of the consequences of the RAAS system is an increase in the generation of the reactive oxygen species (ROS) that causes an increase in oxidative stress, which may play a role in the development or exacerbation of such pathological conditions. Blocking this system at multiple points has been advantageous in the clinical management of these disorders. The key blockers that had gained predominant clinical use for such manifestations were angiotensin receptor blockers and angiotensin-converting enzyme (ACE) inhibitors. However, their prolonged use caused a compensatory increase in renin and angiotensin I levels. The blocking of the system at the initial stages by blocking renin was of advantage to overcome such compensation. Such a renin blocker that gained widespread use was aliskiren. It is the first oral renin inhibitor that was approved for use in 2007. Although the opinions are varied about the use and future of renin inhibitors as antihypertensive agents, aliskiren has been well documented to have antioxidant effects. Aliskiren functions as an antioxidant by lowering the increase in ROS that are produced by the RAAS system at doses independent of decreasing the blood pressure. In the present review we discuss the antioxidant properties of aliskiren independent of its blood pressure lowering property.