Autophagy and Venous Endothelial Function

The molecular mechanisms involved in venous endothelial dysfunction are largely unknowns. Autophagy is an intracellular mechanism devoted to the removal of damaged cytoplasmic elements. Previous evidence demonstrated that activation of autophagy exerts beneficial effects in the cardiovascular system, reducing cardiac damage and improving cardiac function in response to stress. However, the association between venous endothelial dysfunction and autophagy remains to be characterized. In this study the investigators will test whether reactivation of autophagy through a natural compound (spermidine) is able to improve vascular function in saphenous veins derived from patients subjected to saphenectomy. The same outcome will be evaluated in saphenous veins isolated from patients with atherosclerotic obstructive disease of the lower limbs subjected revascularization through implantation of venous by-pass.

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

Eligibility Criteria:
Inclusion Criteria:

* Eligible subjects undergoing saphenectomy
* Patients with chronic venous insufficiency
* Patients with varicose veins
* Eligible subjects undergoing peripheral artery revascularization through implantation of venous by-pass derived from saphenous vein
* Acceptance and signature of the informed consent

Exclusion Criteria:

* Chronic and acute Inflammatory diseases
* Immunological and rheumatic diseases
* Pre-existing or ongoing neoplasms
* Infectious diseases
* Previous organ transplantation
* Treatment with pharmacological therapies able to modulate autophagy, i. e. rapamycin and derivative compounds (rapalogues).
* Antioxidant therapies in the last three months
* Patients with surgical technical complications