Tissue distribution of quercetin in rats and pigs.
Quercetin is a dietary polyphenolic compound with potentially beneficial effects on health. Claims that quercetin has biological effects are based mainly on in vitro studies with quercetin aglycone. However, quercetin is rapidly metabolized, and we have little knowledge of its availability to tissues. To assess the long-term tissue distribution of quercetin, 2 groups of rats were given a 0.1 or 1% quercetin diet [approximately 50 or 500 mg/kg body weight (wt)] for 11 wk. In addition, a 3-d study was done with pigs fed a diet containing 500 mg quercetin/kg body wt. Tissue concentrations of quercetin and quercetin metabolites were analyzed with an optimized extraction method. Quercetin and quercetin metabolites were widely distributed in rat tissues, with the highest concentrations in lungs (3.98 and 15.3 nmol/g tissue for the 0.1 and 1% quercetin diet, respectively) and the lowest in brain, white fat, and spleen. In the short-term pig study, liver (5.87 nmol/g tissue) and kidney (2.51 nmol/g tissue) contained high concentrations of quercetin and quercetin metabolites, whereas brain, heart, and spleen had low concentrations. These studies have for the first time identified target tissues of quercetin, which may help to understand its mechanisms of action in vivo.
RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen, The Netherlands.
Vincent C J
VC
de Boer
Ashwin A
AA
Dihal
Hester
H
van der Woude
Ilja C W
IC
Arts
Siegfried
S
Wolffram
Gerrit M
GM
Alink
Ivonne M C M
IM
Rietjens
Jaap
J
Keijer
Peter C H
PC
Hollman
D000818:Animals; D001682:Biological Availability; D001835:Body Weight; D002851:Chromatography, High Pressure Liquid; D008297:Male; D011794:Quercetin / Q000493:pharmacokinetics*; D051381:Rats; D011916:Rats, Inbred F344; D013552:Swine; D014018:Tissue Distribution
D011794:Quercetin