title: Effects of baicalin on oral pharmacokinetics of caffeine in rats.
abstract: Scutellaria baicalensis is one of the most widely used herbal medicines in East Asia. Because baicalein and baicalin are major components of this herb, it is important to understand the effects of these compounds on drug metabolizing enzymes, such as cytochrome P450 (CYP), for evaluating herb-drug interaction. The effects of baicalin and baicalein on activities of ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), benzyloxyresorufin O-debenzylase (BROD), p-nitrophenol hydroxylase and erythromycin N-demethylase were assessed in rat liver microsomes in the present study. In addition, the pharmacokinetics of caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) in baicalin-treated rats were compared with untreated control. As results, EROD, MROD and BROD activities were inhibited by both baicalin and baicalein. However, there were no significant differences in the pharmacokinetic parameters of oral caffeine and its three metabolites between control and baicalin-treated rats. When the plasma concentration of baicalin was determined, the maximum concentration of baicalin was below the estimated IC50 values observed in vitro. In conclusion, baicalin had no effects on the pharmacokinetics of caffeine and its metabolites in vivo, following single oral administration in rats.
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Keumhan
authors.initials: K
authors.lastname: Noh
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Mahesh Raj
authors.initials: MR
authors.lastname: Nepal
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Ki Sun
authors.initials: KS
authors.lastname: Jeong
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Sun-A
authors.initials: SA
authors.lastname: Kim
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Yeon Ji
authors.initials: YJ
authors.lastname: Um
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Chae Shin
authors.initials: CS
authors.lastname: Seo
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Mi Jeong
authors.initials: MJ
authors.lastname: Kang
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Pil-Hoon
authors.initials: PH
authors.lastname: Park
authors.affiliation: College of Pharmacy, Chung-Ang University, Seoul 156-756, Republic of Korea.
authors.forename: Wonku
authors.initials: W
authors.lastname: Kang
authors.affiliation: College of Pharmacy, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Hye Gwang
authors.initials: HG
authors.lastname: Jeong
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Tae Cheon
authors.initials: TC
authors.lastname: Jeong
keywords: Baicalein; Baicalin; Caffeine; Drug interaction; Pharmacokinetics