Via practica 4/2020

Influence of natural flavonoids on parameters of oxidative stress in patients with erectile dysfunction

Introduction: Erectile dysfunction is a transient or permanent inability to obtain and maintain erection adequate for satisfactory sexual intercourse. Erectile dysfunction is associated with other diseases affecting the vascular, nervous and endocrine system or penile structures responsible for erection. Endothelium is a key regulator of vascular physiology and pathology. Oxidative stress can significantly contribute endothelial damage. Antioxidant treatment is one of the options for improving endothelial function. Patients and methods: A double-blind, randomized, placebo-controlled study enrolled 77 patients with erectile dysfunction diagnosed by the IIEF-5 questionnaire. Patients were randomized into three groups and given natural antioxidants Pycnogenol, Egb 791 or placebo for three months. The level of total nitric oxide, antioxidant capacity of plasma, activity of antioxidant enzyme paraoxonase 1 on its arylestrase activity, markers of oxidative damage of lipids – malondialdehyde and 8-isoprostanes, markers of oxidative damage of proteins – protein carbonyls and late phase glycation products were examined. Results: After three months of administration, there was nonsignificant increase of total nitric oxide levels. Plasma antioxidant capacity, similar to paraoxonase 1 activity was not significantly changed by administration of Pycnogenol or extract of Ginkgo biloba (Egb 761). Neither PYC nor Egb 761 had a positive effect on protein carbonyl formation. However, both preparations significantly decreased the levels of oxidative damaged lipids and insignificantly reduced the level of late phase glycation products. Placebo did not significantly alter any of the endpoints. Conclusion: Our results indicate, that oxidative stress plays an important role in the etiopathogenesis of erectile dysfunction through endothelial damage and administration of natural antioxidants eliminates the formation of oxidatively damaged biomolecules. Elimination of oxidative stress with antioxidants can improve endothelial function. As erectile dysfunction is a marker of early coronary or cerebral artery damage, improvement of endothelial function will also reduce the risk of future cardiovascular events.

Keywords: erectile dysfunction, endothelial dysfunction, oxidative stress, natural antioxidants