Nitric Oxide and Aging Blood Vessels
Nitric oxide levels are a possible target for therapies aimed at some of the signs of aging in blood vessels: "Many disorders emerge with advancing aging, and cardiovascular diseases (CVD) are a major cause of morbidity and mortality in the elderly. The term vascular aging encompasses all the structural and functional alterations in the blood vessels with progressive aging. Both smooth muscle cells and intima layers are affected. These vascular changes lead to endothelial dysfunction, arterial stiffness in consequence of intense remodeling and calcification, impaired angiogenesis, greater susceptibility to vascular injury and atherosclerotic lesions. The mechanisms underlying vascular aging are complex and involve multiple pathways and factors ... In this complex scenario, vascular function depends on the balanced production/bioavailability of nitric oxide (NO), which is maintained by the normal activity of endothelial nitric oxide synthase (eNOS). On the other hand, excessive amount of NO produced by inducible nitric oxide synthase (iNOS) up-regulation contributes to vascular dysfunction. Evidence obtained from experimental models indicates that decreased NO bioavailability as well as increased reactive nitrogen species (RNS) production contributes to aging-associated vascular dysfunction. ... Pharmacological modulation of NO generation and expression/activity of NOS isoforms may represent a therapeutic alternative to prevent the progression of cardiovascular diseases."