著者
Takeshi AKIYOSHI Marie ITO Saori MURASE Mitsue MIYAZAKI F. Peter GUENGERICH Katsunori NAKAMURA Koujirou YAMAMOTO Hisakazu OHTANI
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.28, no.5, pp.411-415, 2013 (Released:2013-10-25)
参考文献数
31
被引用文献数
21

Inhibition of cytochrome P450 (CYP) 3A4 is the major cause of drug-drug interactions (DDI). We have previously reported that the genetic variation of CYP3A4 significantly affected the inhibitory profiles of typical competitive inhibitors. In addition to competitive inhibition, some clinically significant DDI are attributable to mechanism-based inhibition (MBI). However, the differences in the MBI kinetics among CYP3A4 genetic variants remain to be characterized. In this study, we quantitatively investigated the inhibition kinetics of MBI inhibitors, erythromycin and clarithromycin, on the CYP3A4 variants CYP3A4.1, 4.2, 4.7, 4.16, and 4.18. The activity of CYP3A4 was assessed using testosterone 6β-hydroxylation with recombinant CYP3A4. Both erythromycin and clarithromycin decreased the activity of CYP3A4 in a time-dependent manner. The maximum inactivation rate constants, kinact,max, of erythromycin for CYP3A4.2 and CYP3A4.7 were 0.5-fold that for CYP3A4.1, while that for CYP3A4.16 and CYP3A4.18 were similar to that for CYP3A4.1. The KI values of erythromycin for CYP3A4.2, 4.7, 4.16, and 4.18 were 1.2-, 0.4-, 2.2- and 0.72-fold those of CYP3A4.1, respectively. Similar results were obtained for clarithromycin. In conclusion, the inhibitory profiles of MBI inhibitors, as well as competitive inhibitors, may possibly differ among CYP3A4 variants. This difference may contribute to interindividual differences in the extent of DDI based on MBI.
著者
Hongye Han Takeshi Akiyoshi Tokio Morita Toshiaki Tsuchitani Momoko Nabeta Kodai Yajima Ayuko Imaoka Hisakazu Ohtani
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.46, no.12, pp.1745-1752, 2023-12-01 (Released:2023-12-01)
参考文献数
41
被引用文献数
1

Jabara juice and its component narirutin inhibit the activity of organic anion-transporting polypeptides (OATPs) 1A2 and OATP2B1, which are considered to play significant roles in the intestinal absorption of fexofenadine. In this study, we investigated the effects of jabara juice on the intestinal absorption of fexofenadine in mice and the inhibitory effects of jabara juice and narirutin on the permeation of fexofenadine using Caco-2 cell monolayers and LLC-GA5-COL300 cell monolayers. In the in vivo study, the area under the plasma concentration–time curve (AUC) of fexofenadine in mice was increased 1.8-fold by jabara juice. In the permeation study, 5% jabara juice significantly decreased the efflux ratio (ER) of fexofenadine for Caco-2 monolayers. Furthermore, the ERs of fexofenadine and digoxin, which is a typical substrate of P-glycoprotein (P-gp), for LLC-GA5-COL300 cell monolayers were decreased in a concentration-dependent manner by jabara juice extract, suggesting that jabara juice may increase the intestinal absorption of fexofenadine by inhibiting P-gp, rather than by narirutin inhibiting OATPs. The present study showed that jabara juice increases the intestinal absorption of fexofenadine both in vivo and in vitro. The intestinal absorption of fexofenadine may be altered by the co-administration of jabara juice in the clinical setting.