title: Characteristic rat tissue accumulation of nobiletin, a chemopreventive polymethoxyflavonoid, in comparison with luteolin.
abstract: Nobiletin (NOB), a polymethoxyflavonoid, is an effective anti-inflammatory and chemopreventive phytochemical found in citrus fruits. We compared the absorption and metabolism characteristics of NOB with those of luteolin (LT) in male SD rats. Each flavonoid (67.1 micromol/kg of body weight) was given separately by gastric intubation, and then concentrations were measured at 1, 4, and 24 hours after administration. In the digestive organs, NOB showed a notable tendency for localizing into the mucous membrane and muscularis from 1 to 4 hours, in contrast to LT, though both NOB and LT were completely excreted within 24 hours. Further, significant amounts of NOB were detected in the whole liver and kidney specimens, whereas LT accumulation was slight. Although serum concentrations of NOB from 1 to 4 hours were comparable to those of LT, urinary concentrations of LT were significantly higher from 4 to 24 hours. Following glucuronidase/sulfatase treatments of urinary materials, we detected 3 types of mono-demethylated NOB, including 3'-demethyl-NOB, and two di-demethylated types, as well as 3'-demethyl-NOB alone in serum samples using liquid chromatography-mass spectral analysis. Our results suggest that the metabolic properties of polymethoxyflavonoids are distinct from those of other general flavonoids, because of their wide distribution and accumulation in tissue.
authors.affiliation: Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan. cancer@kais.kyoto-u.ac.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Murakami
authors.forename: Koichi
authors.initials: K
authors.lastname: Koshimizu
authors.forename: Hajime
authors.initials: H
authors.lastname: Ohigashi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kuwahara
authors.forename: Wataru
authors.initials: W
authors.lastname: Kuki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Keisuke
authors.initials: K
authors.lastname: Hosotani
authors.forename: Satsuki
authors.initials: S
authors.lastname: Kawahara
authors.forename: Yumi
authors.initials: Y
authors.lastname: Matsuoka
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D047309:Flavones; D005419:Flavonoids / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D005753:Gastric Mucosa / Q000737:chemistry; D007420:Intestine, Large / Q000737:chemistry; D007421:Intestine, Small / Q000737:chemistry; D007700:Kinetics; D047311:Luteolin; D008297:Male; D051381:Rats; D013270:Stomach / Q000737:chemistry; D014018:Tissue Distribution
chemical_list: D016588:Anticarcinogenic Agents; D047309:Flavones; D005419:Flavonoids; C008661:nobiletin; D047311:Luteolin