#B199 Resveratrol-14C Disposition in Intestinal Epithelial Cells and in vivo in Humans. U. Walle, Renee E. Hypolite, Mark I. Kaldas, Thomas Walle, Medical Univ. of South Carolina, Charleston, SC. Resveratrol is a dietary polyphenol present in grapes, red wine and peanuts, which has been strongly indicated to have protective effects against cancer, through a variety of cell signaling mechanisms. Proposed cancer preventive target sites for resveratrol include colon, skin, breast, lung, prostate, liver and pancreas. However, it is not known if dietary resveratrol will actually reach these multiple proposed sites of actions. In this study we examined the transport of [14C]resveratrol across the human intestinal Caco-2 cell monolayer, a well established model of human intestinal absorption, as well as its absorption and bioavailability after oral and i.v. doses in six human volunteers. Rapid transcellular transport across the Caco-2 cell monolayer occurred in a direction-independent manner with a Papp value of ¡Ö 7 x 10-6 cm/sec, suggesting efficient absorption in vivo. However, metabolism, mainly due to sulfate conjugation, was extensive, suggesting that the oral bioavailability may be very low. Interestingly, there was as much as a 35-fold accumulation of resveratrol in the Caco-2 cells. In the clinical study the estimated absorption of a 25 mg oral dose was 75 10% with peak plasma levels of radioactivity (1 hr) of 510 80 ng/ml and a plasma half-life of 9.2 0.6 hr. About 80% of the dose, both oral and iv, was recovered in urine and feces in 72 hr. No unchanged resveratrol could be detected in the plasma after the oral dose. Major metabolites of resveratrol were due to sulfate conjugation. In conclusion, both the in vitro and in vivo studies support the view that the systemic availability of resveratrol in humans is very low. However, a very high Caco-2 cell accumulation may point to sites, i.e. epithelial cells along the aerodigestive tract, where the cancer preventive actions of resveratrol may de displayed. Supported by the National Institutes of Health grant CA89795. Frontiers in Cancer Prevention Research, 2003 AACR Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.