Melatonin and hydroxytyrosol protect against oxidative stress related to the central nervous system after the ingestion of three types of wine by healthy volunteers

Abstract

Adrenic acid (AdA) and docosahexaenoic acid (DHA) peroxidation produces F₂-dihomo-IsoPs and neuroprostanes, which have been related to oxidative damage in the central nervous system. Besides polyphenols, melatonin (MEL) and hydroxytyrosol (OHTyr) could be partly responsible for the antioxidant benefits of red wine (excluding colon derivatives). In order to elucidate whether these compounds are responsible for the protective antioxidant effects of red wine, a double-blind, crossover, placebo-controlled in vivo study – involving the intake of red wines and their native musts by healthy volunteers – was performed. The urinary metabolites decreased after the administration of red wines, to a greater extent than after the intake of their corresponding musts or ethanol. Melatonin is the most effective compound that protects adrenic acid from oxidative attack, judged by the reduction in the formation of F₂-dihomo-isoprostanes. Similarly, hydroxytyrosol, being the most effective bioactive compound in reducing the formation of F₃-neuroprostanes n-6 DPA and F₄-neuroprostanes, protected docosahexaenoic and eicosapentaenoic acids from oxidative attack.