title: Changes in the concentrations of vitamin E analogs and their metabolites in rat liver and kidney after oral administration.
abstract: Vitamin E analog, such as α- and γ-tocopherol, can undergo ω-oxidation without cleavage of the chroman ring, and this pathway is responsible for generation of the major urinary vitamin E metabolite, carboxyethyl hydroxychroman. However, it is still unclear how carboxyethyl hydroxychroman is changed in various tissues after vitamin E intake. We therefore investigated changes in the concentrations of α- and γ-tocopherol and their metabolites in rat liver and kidney. The concentration of α-tocopherol in rat liver increased until 6 h after oral administration, and then decreased. The change in the concentration of α-carboxyethyl hydroxychroman in rat liver in the α-Toc group slowly increased until 12 h after oral administration. Cytochrome P450 3A1 mRNA expression significantly increased from 12 h after the start of α-tocopherol administration. The change in the concentration of γ-carboxyethyl hydroxychroman in rat liver in the γ-Toc group markedly increased until 12 h after oral administration. On the other hand, γ-carboxyethyl hydroxychroman in rat kidney showed greater accumulation than α-carboxyethyl hydroxychroman from 3 h to 24 h after oral administration. From these results, we considered that γ-carboxyethyl hydroxychroman formed in the liver continues to be released into the bloodstream and is transported to the kidney rapidly.
authors.affiliation: Department of Applied Chemistry, Graduate School of Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan ; Department of Nutrition and Life Science, Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Chikako
authors.initials: C
authors.lastname: Kiyose
authors.affiliation: Department of Nutrition and Life Science, Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Saito
authors.affiliation: Department of Nutrition and Life Science, Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Rieko
authors.initials: R
authors.lastname: Yachi
authors.affiliation: Department of Applied Chemistry, Graduate School of Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Muto
authors.affiliation: Department of Applied Chemistry, Graduate School of Kanagawa Institute of Technology, 1030 Shimoogino, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Igarashi
keywords: CEHC; CYP3A; Vitamin E metabolism; rat kidney; rat liver