Thalidomide increases human hepatic cytochrome P450 3A enzymes by direct activation of the pregnane X receptor.
Heterotropic cooperativity of human cytochrome P450 (P450) 3A4/3A5 by the teratogen thalidomide was recently demonstrated by H. Yamazaki et al. ( ( 2013 ) Chem. Res. Toxicol. 26 , 486 - 489 ) using the model substrate midazolam in various in vitro and in vivo models. Chimeric mice with humanized liver also displayed enhanced midazolam clearance upon pretreatment with orally administered thalidomide, presumably because of human P450 3A induction. In the current study, we further investigated the regulation of human hepatic drug metabolizing enzymes. Thalidomide enhanced levels of P450 3A4 and 2B6 mRNA, protein expression, and/or oxidation activity in human hepatocytes, indirectly suggesting the activation of upstream transcription factors involved in detoxication, e.g., the nuclear receptors pregnane X receptor (PXR) and constitutive androstane receptor (CAR). A key event after ligand binding is an alteration of nuclear receptor conformation and recruitment of coregulator proteins that alter chromatin accessibility of target genes. To investigate direct engagement and functional alteration of PXR and CAR by thalidomide, we utilized a peptide microarray with 154 coregulator-derived nuclear receptor-interaction motifs and coregulator and nuclear receptor boxes, which serves as a sensor for nuclear receptor conformation and activity status as a function of ligand. Thalidomide and its human proximate metabolite 5-hydroxythalidomide displayed significant modulation of coregulator interaction with PXR and CAR ligand-binding domains, similar to established agonists for these receptors. These results collectively suggest that thalidomide acts as a ligand for PXR and CAR and causes enzyme induction leading to increased P450 enzyme activity. The possibilities of drug interactions during thalidomide therapy in humans require further evaluation.
Showa Pharmaceutical University, Machida, Japan.
Norie
N
Murayama
PamGene International, Den Bosch, Netherlands.
Rinie
R
van Beuningen
Central Institute for Experimental Animals, Kawasaki, Japan.
Hiroshi
H
Suemizu
Biopredic International, Rennes, France.
Christiane Guguen
CG
Guillouzo
5Nagoya Institute of Technology, Nagoya, Japan.
Norio
N
Shibata
Showa Pharmaceutical University, Machida, Japan.
Kanako
K
Yajima
Showa Pharmaceutical University, Machida, Japan.
Masahiro
M
Utoh
Showa Pharmaceutical University, Machida, Japan.
Makiko
M
Shimizu
Biopredic International, Rennes, France.
Christophe
C
Chesné
Central Institute for Experimental Animals, Kawasaki, Japan.
Masato
M
Nakamura
Vanderbilt University School of Medicine, Nashville, TN, USA.
F Peter
FP
Guengerich
PamGene International, Den Bosch, Netherlands.
René
R
Houtman
Showa Pharmaceutical University, Machida, Japan.
Hiroshi
H
Yamazaki
D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics / Q000378:metabolism; D001711:Biotransformation; D002460:Cell Line; D002478:Cells, Cultured; D000090702:Constitutive Androstane Receptor; D065702:Cytochrome P-450 CYP2B6; D051544:Cytochrome P-450 CYP3A / Q000235:genetics / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism*; D006801:Humans; D000077297:Pregnane X Receptor; D040081:Protein Array Analysis; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D011987:Receptors, Steroid / Q000378:metabolism*; D013792:Thalidomide / Q000494:pharmacology*
D000090702:Constitutive Androstane Receptor; D000077297:Pregnane X Receptor; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D013792:Thalidomide; D001189:Aryl Hydrocarbon Hydroxylases; C585599:CYP2B6 protein, human; D065702:Cytochrome P-450 CYP2B6; D051544:Cytochrome P-450 CYP3A