Address for correspondence: Fulvio Ursini, M.D., Department of Biochemistry, University of Padova, Viale G. Colombo 3, Padova 35121, Italy. Voice: 39-049-8276104; fax: 39-049-8073310.
ursini{at}mail.bio.unipd.it
Ann. N.Y. Acad. Sci. 957: 200-209 (2002).
One of the key elements of Mediterranean diet is the use of
wine, usually taken with foods. Besides the evidence from human
experience and ancient medicine, modern experimental data support
the notion that the most striking effect of wine in protecting
against cardiovascular disease involves the reduction of oxidative
damage to plasma lipoproteins. This oxidative damage is thought
to be mediated by eating foods containing oxidized lipids. In
fact, eating a meal containing oxidized lipids increases the
plasma level of lipid hydroperoxides and increases the susceptibility
to oxidation of LDL. The postprandial increase of LDL-, an oxidatively
modified form of LDL, where apoB is unfolded and sinking in
the core of the particle, is a valuable biomarker for this food-derived
oxidative stress in plasma. Wine, taken with foods minimizes
the postprandial rise of lipid hydroperoxides and LDL- and abolishes
the increase of LDL oxidability. Among wine antioxidants, the
best candidates for providing an antioxidant effect are procyanidins.
These compounds are considered better antioxidants than the
corresponding monomers containing catechol groups. This is due
to the hydrogen transfer mechanism for the radical-scavenging
reaction, which renders the reaction more specific for peroxyl
radicals and pH independent. Moreover, the fast intramolecular
disproportion among aroxyl radicals pulls the antioxidant reaction
by both decreasing the oxidation potential and increasing the
rate of the reaction. Apparently, wine procyanidins are active
in preventing lipid oxidation of foods while in the digestive
tract, thus preventing the postprandial plasma rise in oxidants.
The likely limited bioavailability of these compounds, therefore,
does not affect their relevance as key elements for optimizing
nutrition and reducing risk of atherogenesis. Accordingly, studies
with rabbits fed a high cholesterol diet show that grapeseed
procyanidins are strongly protective not only in terms of reducing
plasma lipid peroxides, but they also markedly inhibit lipid-laden
foam-cell deposition. Drinking wine at meals provides this kind
of protection, and the final benefits are realized by the prevention
of the development of atheromatous lesions even under conditions
of hypercholesterolemia.