Autophagy is a reparative, life-sustaining process by which cytoplasmic components are sequestered in double-membrane vesicles and degraded on fusion with lysosomal compartments. Growing evidence reveals that basal autophagy is an essential in vivo process mediating proper vascular function. Moreover, autophagy is stimulated by many stress-related stimuli in the arterial wall to protect endothelial cells and smooth muscle cells against cell death and the initiation of
vascular disease, in particular
atherosclerosis. Basal autophagy is atheroprotective during early
atherosclerosis but becomes dysfunctional in advanced
atherosclerotic plaques. Little is known about autophagy in other vascular disorders, such as
aneurysm formation, arterial aging, vascular stiffness, and chronic venous disease, even though autophagy is often impaired. This finding highlights the need for pharmacological interventions with compounds that stimulate the prosurvival effects of autophagy in the vasculature. A large number of animal studies and clinical trials have indicated that oral or
stent-based delivery of the autophagy inducer
rapamycin or derivatives thereof, collectively known as
rapalogs, effectively inhibit the basic mechanisms that control growth and destabilization of
atherosclerotic plaques. Other autophagy-inducing drugs, such as
spermidine or add-on
therapy with widely used antiatherogenic compounds, including
statins and
metformin, are potentially useful to prevent
vascular disease with minimal adverse effects.