Autophagy and Venous Endothelial Function

Endothelial dysfunction contributes to different cardiovascular diseases, such as atherosclerosis, myocardial infarction, stroke and peripheral artery diseases. Recent evidence also demonstrated that endothelial dysfunction is associated with vascular venous diseases. In this regard, venous endothelial dysfunction contributes to the development of varicose veins and deep vein thrombosis. Disequilibrium in endothelial function is also present in venous traits derived from saphenous veins which are routinely used as aortocoronary by-pass. The molecular mechanisms involved in venous diseases require further investigations. Autophagy, the intracellular mechanism devoted to the removal of dysfunctional or senescent cytoplasmic elements may represent a new therapeutic target for the treatment of vascular diseases. In this regard, it has been demonstrated that the enhancement of autophagy limits cardiac injury in pre-clinical models of cardiovascular diseases. However, the association between autophagy and vascular disease is still unknown in humans. Spermidine is a natural activator of autophagy which has been demonstrated to extend lifespan in mice and to reduce cardiac dysfunction through autophagy-dependent mechanisms. The objectives of this study will be the following: 1) to test whether spermidine is able to improve vascular function and to reduce oxidative stress in saphenous veins obtained from patients subjected to saphenectomy due to chronic venous insufficiency or varicose veins; 2) to test whether spermidine is able to improve vascular function in saphenous veins derived from patients with atherosclerotic obstructive disease of lower limbs subjected to revascularization through implantation of arteriosus by-pass. In a different set of experiments, the investigators will also test whether vein portions incubated with spermidine show increased autophagy and decreased markers of oxidative stress with respect to controls. The investigators expect that venous segments treated with spermidine will show an amelioration of endothelial function