Bioavailability of resveratrol

There is an extensive amount of literature on the in vitro activities of resveratrol. Bertelli et al. [1996] were the first to study the bioavailability of resveratrol in rats. They assessed analysis of plasma and tissues from rats that were administered red wine in a single dose or a regular dose for 15 day. Results indicated that resveratrol is quickly absorbed with a maximum peak at 1 h in plasma as well as in liver and kidney, although in the heart it peak at 2 h. Values obtained after regular consumption of red wine were higher than without the regular consumption in the different organs studies, in particular in the liver. The kidney seemed to be the main route of excretion (Table 13.2) [Bertelli et al., 1996]. 

Studies that investigate the bioavailability of resveratrol in humans are scarce. Moreover, the research in this area is quite recent. It has been summarized in Table 13.5. The experimental approaches have been improved with the use of new analytical techniques such as mass spectrometry to identify and quantify metabolites present in very low concentrations. Resveratrol and its metabolites have been measured in several biofluids plasma or serum, urine, LDL, and feces. 

Zamora-Ros et al [2006] carried out the first work that assessed the bioavailability of resveratrol (provided by different wines) in a regular intervention during 28 day. The analyses were performed by LC-MS/MS. In the first study, 10 healthy males were recruited to consume 300 mL/day of sparkling wine (1.19 mg resveratrol/1). After 28 day of supplementation, urinary trans-and m-resveratrol-3-O-glucuronides were 75 and 38 nmol/g creatinine, respectively. In the second study, 10 healthy females were selected to consume 200 mL of white wine (1.99 mg resveratrol/L) or 200 mL of red wine (12.8 mg resveratrol/L) in a crossover clinical trial. Likewise after 28 days only resveratrol metabolites were detected in morning urine, trans- (205 and 473 nmol/g creatinine) and ra-resveratrol-3-O-glucuronidcs (58 and 140 nmol/g creatinine) were found after white and red wine intake, respectively. Those studies showed that urinary excretion was dose dependent. Furthermore, slight amounts of resveratrol metabolites were also detected at baseline periods. No free resveratrol or piceid were detected in any of the studies. 

Walle, T., Hsieh, F., Delegge, M.H., Oatis, J.E., Jr. and Walle, U.K. (2004) High absorption but very low bioavailability of resveratrol in humans. Drug Metabolism and Disposition The Biological Fate of Chemicals, 32, 1377—1382. 

The plant polyphenol trani-resveratrol (3, 5, 4 -trihydroxystilbene), mainly found in grape, peanut, and other few plants, displays a wide range of biological effects. Numerous in vitro studies have described various biological effects of resveratrol. In order to provide more information regarding absorption, metabolism, and bioavailability of resveratrol, different research approaches... 

Caco-2 cells and isolated small intestine are models of basic nutrition that contributed to the understanding of resveratrol absorption and bioavailability. While the Caco-2 absorption model is a well-defined cellular in vitro system based on a human colonic adenocarcinoma cell line, the isolated small intestine model is nearer to in vivo conditions and is also simpler to handle. It also avoids the methodological problems of in vivo perfusion models [Barthe et al., 1998, 1999]. 

Various studies have focused on the metabolism of piceid, the glucoside of resveratrol. These studies are of great interest due to the higher amount of piceid compared to resveratrol in food. Therefore, bioavailability studies of this compound are required. In vitro studies have already observed the absorption of piceid in the enterocytes, but in vivo studies in animal models are still scarce. 

Andlauer W, Kolb J, Siebert K, Furst P. 2000. Assessment of resveratrol bioavailability in the perfused small intestine of the rat. Drugs Exp Clin Res 26 47-55. 

Vitaglione P, Sforza S, Galaverna G, Ghidini C, Caporaso N, Yescovi PP, Fogliano Y, Marchelli R. 2005. Bioavailability of traw-resveratrol from red wine in humans. Mol Nutr Food Res 49 495-504. 

Walle T, Hsieh F, DeLegge MH, Oatis JE, Walle UK. 2004. Fligh absorption but very low bioavailability of oral resveratrol in humans. Drug Metab Dispos 32 1377-1382. 

Vitaglione, R, Sforza, S., Galavema, G., Ghidini, C., Caporaso, N., Vescovi, P. R, Fogliano, V, Marchelli, R. (2005). Bioavailability of trans-resveratrol from red wine in humans. Mol. Nutr. Food Res., 49, 495-504. 

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