19 December 2001. Just in time to ponder this weighty question comes a short
communication in tomorrow's Nature. Martin Carrier and colleagues at the William
Harvey Research Institute in London report that polyphenols in red wines potently
inhibit expression of the vasoconstrictor peptide endothelin-1.
If confirmed, this finding could advance the related debates on what it is
about moderate alcohol consumption that protects the heart, and whether the
French paradox-despite equal saturated fat consumption, the Frogs have less
coronary artery disease than the Roast Beeves-is a real phenomenon that is due
to the French love for vin rouge.
Roger Corder et al. tested alcohol-free extracts of 23 red and four white wines,
one rosé wine, as well as red grape juice on bovine aortic endothelial cells.
They found that red wines reduced endothelin-1 gene expression in direct proportion
to their polyphenol content, while red grape juice was only weakly active and
the whites and the rosé failed to do the trick. Perhaps, though, the French
should drink the competition's product: South American Cabernet was the most
potent, with two microliters of extract per milliliter solution achieving a 50
percent endothelin-1 inhibition. Overall, polyphenol IC50 activity was in the
Though polyphenols have antioxidant properties, this is probably not their
modus operandi here. Instead, Corder et al. speculate that polyphenols might
interfere with tyrosine kinase signaling, though this conclusion is based on
only one immunocytochemistry experiment showing a redistribution of phosphotyrosine
staining in cultured cells, and other literature. Red wine extract is already
known to induce vasodilation and thus lower blood pressure.
What could this mean for the brain? Endothelins are normally expressed in endothelial
cells of small blood vessels in the brain, and their expression is induced in
reactive astrocytes (Nie
XY et al., 1996). Some data suggest that Aβ enhances endothelin-1-mediated
et al. 1999) and that Gingko biloba exerts its purported memory-enhancing
effects via endothelin-1 inhibition. Finally, recent work suggests endothelins
might worsen brain damage after experimentally induced stroke in rats in part
by making the blood-brain barrier more permeable (Matsuo
et al., 2001).
"I would expect red wine polyphenols to inhibit endothelin-1 expression in
brain endothelial cells," said Corder, though he has not studied this question.
Maybe someone should? Meanwhile, all the more reason for otherwise healthy people
to enjoy that glass of Cabernet guilt-free.-Gabrielle Strobel.
Reference:Corder R et al. Endothelin-1 synthesis reduced by red wine.
Nature 2001 December 20/27;(414):863-864. Abstract