Murine Cyp3a knockout chimeric mice with humanized liver: prediction of the metabolic profile of nefazodone in humans.
Chimeric mice with humanized livers (PXB mice) are used to investigate the metabolism and pharmacokinetics of drugs in humans. However, residual murine enzymatic activities derived from the liver and the presence of mouse small intestinal metabolism can hamper the prediction of human drug metabolism. Recently murine Cytochrome P450 3a gene knockout chimeric mice with humanized livers (Cyp3a KO CM) were developed. To evaluate the prediction of drug metabolism, nefazodone (NEF) was administered orally at 10 mg/kg to the following mouse strains: Cyp3a KO CM, murine Cyp3a gene knockout (Cyp3a KO), PXB and severe combined immunodeficiency (SCID) mice. Liquid chromatography-mass spectrometry was used for metabolic profiling of plasma, urine and bile. The prediction of human metabolite levels such as hydroxy nefazodone (OH-NEF), triazoledione form (TD), m-chlorophenylpiperazine and dealkyl metabolites in Cyp3a KO CM was superior to that in Cyp3a KO, PXB or SCID mice. Further, clinical exposure levels of NEF, OH-NEF and TD were reproduced in Cyp3a KO CM. In contrast, NEF was rapidly metabolized to TD in both PXB and SCID mice but not in Cyp3a KO mice, suggesting that murine CYP3A is involved in the elimination of NEF in these mice. These findings demonstrate that the metabolic profile of NEF in Cyp3a KO CM differs qualitatively and quantitatively from that in PXB mice due to the higher metabolic rate of NEF and its metabolites via murine CYP3A. Therefore Cyp3a KO CM might be useful in predicting the metabolic profiles of drug candidates in humans.
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Naoyuki
N
Nakada
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Akio
A
Kawamura
ADME & Tox Research Institute, Sekisui Medical Co., Ltd, Tokyo, Japan.
Hidetaka
H
Kamimura
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Koya
K
Sato
Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan.
Yasuhiro
Y
Kazuki
PhoenixBio, Co., Ltd, Higashi Hiroshima, Hiroshima, Japan.
Masakazu
M
Kakuni
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Masato
M
Ohbuchi
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Kota
K
Kato
PhoenixBio, Co., Ltd, Higashi Hiroshima, Hiroshima, Japan.|Liver Research Project Center, Hiroshima University, Japan.
Chise
C
Tateno
Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan.
Mitsuo
M
Oshimura
Drug Metabolism Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan.
Takashi
T
Usui
D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D001646:Bile / Q000737:chemistry; D002675:Child, Preschool; D051544:Cytochrome P-450 CYP3A / Q000235:genetics / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008297:Male; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D016513:Mice, SCID; D008862:Microsomes, Liver / Q000378:metabolism; D010879:Piperazines; D014230:Triazoles / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine
D018687:Antidepressive Agents, Second-Generation; D010879:Piperazines; D014230:Triazoles; C051752:nefazodone; D051544:Cytochrome P-450 CYP3A
Cyp3a knockout; nefazodone; predicting the metabolic profiles of drug candidates in humans