Flavonoids antioxidant actions: starting at the membrane?

C. G. FRAGA; P. I. OTEIZA

Berlin, Alemania

Congreso; Society for Free Radical Research Europe-2008 Congress; 2008

Society for Free Radical Research Europe

Epidemiological evidence demonstrates that diets rich in fruits and vegetables promote health by attenuating or delaying the onset of various diseases, e.g. cardiovascular and neurodegenerative diseases, diabetes, and cancer. The chemical components involved, and the physiological and molecular mechanisms by which fruit and vegetables reduce the risk of disease, are matters of investigation. Flavonoids are polyphenols that are gaining acceptance as responsible for the health benefits offered by fruit and vegetables. Because of their chemical structure, flavanols and related procyanidins (PC) can scavenge free radicals, inactivate other pro-oxidants, and can also interact with a number of biological molecules. We have investigated in Jurkat and Caco-2 cells the effects of epicatechin (EC) and related procyanidins (PC) on cell oxidation. The obtained results indicate that the primary targets of EC and PC seems to be localized at the cell membrane, leading mainly to the regulation NADPH-oxidase activity, and the consequent decreased superoxide production. The proposed interactions of EC and PC with cell membrane (proteins) could better explain the health benefits of flavanols and other flavonoids by making compatible actual tissue levels with the observed antioxidant effects.