Takahito Hirai1, Yuki Nishimura2, Norimitsu Kurata3, Hokuto Namba4, Mariko Iwase1, Yurika Gomi1, Hiromichi Tsuchiya5, Tomoyuki Yamakawa1, Yuji Kiuchi1. 1. Department of Pharmacology, Showa University, School of Medicine, Tokyo, Japan. 2. Department of Pharmacology, Showa University, School of Medicine, Tokyo, Japan yukin@med.showa-u.ac.jp. 3. Faculty of Arts and Sciences at Fujiyoshida, Showa University, Fujiyoshida, Japan. 4. Showa University Clinical Research Institute for Clinical Pharmacology and Therapeutics, Tokyo, Japan. 5. Department of Medical Education, Showa University, School of Medicine, Tokyo, Japan.
Abstract
BACKGROUND/AIM: Benifuuki tea has recently been used as an alternative therapy for pollinosis, and it may be consumed with pharmaceutical drugs. This study aimed to examine cytochrome P450 (CYP)-mediated food-drug interactions with Benifuuki tea in rats. MATERIALS AND METHODS: The inhibitory effects of Benifuuki tea and (-)-epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me) on CYP activities were evaluated in vitro. Midazolam pharmacokinetics was investigated after two treatments with Benifuuki tea. In an ex vivo study, CYP activities were determined after 1-week-treatment with the tea. RESULTS: Benifuuki tea and EGCG3"Me inhibited CYP2D and CYP3A activities in a concentration-dependent manner in vitro. However, MDZ metabolism did not change by Benifuuki treatment in vivo and ex vivo. In contrast, CYP2D activity was decreased ex vivo. CONCLUSION: Normal intake of Benifuuki tea is not likely to cause food-drug interactions by CYP3A inhibition or induction. In contrast, Benifuuki tea consumption may lead to food-drug interactions through the inhibition of CYP2D. Copyright
BACKGROUND/AIM: Benifuuki tea has recently been used as an alternative therapy for pollinosis, and it may be consumed with pharmaceutical drugs. This study aimed to examine cytochrome P450 (CYP)-mediated food-drug interactions with Benifuuki tea in rats. MATERIALS AND METHODS: The inhibitory effects of Benifuuki tea and (-)-epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me) on CYP activities were evaluated in vitro. Midazolam pharmacokinetics was investigated after two treatments with Benifuuki tea. In an ex vivo study, CYP activities were determined after 1-week-treatment with the tea. RESULTS: Benifuuki tea and EGCG3"Me inhibited CYP2D and CYP3A activities in a concentration-dependent manner in vitro. However, MDZ metabolism did not change by Benifuuki treatment in vivo and ex vivo. In contrast, CYP2D activity was decreased ex vivo. CONCLUSION: Normal intake of Benifuuki tea is not likely to cause food-drug interactions by CYP3A inhibition or induction. In contrast, Benifuuki tea consumption may lead to food-drug interactions through the inhibition of CYP2D. Copyright