title: Protection against peroxynitrite by cocoa polyphenol oligomers.
abstract: Flavonoids, natural plant constituents, protect against peroxynitrite and can thereby play a role in defense against this mediator of inflammation. Procyanidin oligomers of different size (monomer through nonamer), isolated from the seeds of Theobroma cacao, were examined for their ability to protect against peroxynitrite-dependent oxidation of dihydrorhodamine 123 and nitration of tyrosine. By molarity, oligomers were more effective than the monomeric epicatechin; the tetramer was particularly efficient at protecting against oxidation and nitration reactions. These results suggest that epicatechin oligomers found in cocoa powder and chocolate may be a potent dietary source for defense against peroxynitrite.
authors.affiliation: Institut für Physiologische Chemie I, Heinrich-Heine-Universität Düsseldorf, Postfach 101007, D-40001, Düsseldorf, Germany.
authors.forename: G E
authors.initials: GE
authors.lastname: Arteel
authors.forename: H
authors.initials: H
authors.lastname: Sies
mesh_terms: D044946:Biflavonoids; D002099:Cacao / Q000737:chemistry*; D002392:Catechin / Q000494:pharmacology*; D005419:Flavonoids; D009566:Nitrates / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology; D011108:Polymers / Q000494:pharmacology; D044945:Proanthocyanidins; D020011:Protective Agents / Q000494:pharmacology*; D012235:Rhodamines / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry
chemical_list: D044946:Biflavonoids; D005419:Flavonoids; D009566:Nitrates; D016877:Oxidants; D010636:Phenols; D011108:Polymers; D044945:Proanthocyanidins; D020011:Protective Agents; D012235:Rhodamines; C058319:dihydrorhodamine 123; C039642:peroxynitric acid; D014443:Tyrosine; C017674:procyanidin; D002392:Catechin