The CYP2D6 Humanized Mouse: Effect of the HumanCYP2D6 Transgene and HNF4α on the Disposition of Debrisoquine in the Mouse
- 1 December 2001
- journal article
- Published by American Society for Pharmacology & Experimental Therapeutics (ASPET)
- Vol. 60 (6), 1260-1267
- https://doi.org/10.1124/mol.60.6.1260
Abstract
CYP2D6 is a highly polymorphic human gene responsible for a large variability in the disposition of more than 100 drugs to which humans may be exposed. Animal models are inadequate for preclinical pharmacological evaluation of CYP2D6 substrates because of marked species differences in CYP2D isoforms. To overcome this issue, a transgenic mouse line expressing the human CYP2D6 gene was generated. The complete wild-type CYP2D6 gene, including its regulatory sequence, was microinjected into a fertilized FVB/N mouse egg, and the resultant offspring were genotyped by both polymerase chain reaction and Southern blotting. CYP2D6-specific protein expression was detected in the liver, intestine, and kidney from only the CYP2D6 humanized mice. Pharmacokinetic analysis revealed that debrisoquine (DEB) clearance was markedly higher (94.1 ± 22.3 l/h/kg), and its half-life significantly reduced (6.9 ± 1.6 h), in CYP2D6 humanized mice compared with wild-type animals (15.2 ± 0.9 l/h/kg and 16.5 ± 4.5 h, respectively). Mutations in hepatic nuclear factor 4α (HNF4α), a hepatic transcription factor known to regulate in vitro expression of the CYP2D6 gene, could affect the disposition of CYP2D6 drug substrates. To determine whether the HNF4α gene modulates in vivo pharmacokinetics of CYP2D6 substrates, a mouse line carrying both the CYP2D6gene and the HNF4α conditional mutation was generated and phenotyped using DEB. After deletion of HNF4α, DEB 4-hydroxylase activity in CYP2D6 humanized mice decreased more than 50%. The data presented in this study show that only CYP2D6 humanized mice but not wild-type mice display significant DEB 4-hydroxylase activity and that HNF4α regulates CYP2D6 activity in vivo. The CYP2D6 humanized mice represent an attractive model for future preclinical studies on the pharmacology, toxicology, and physiology of CYP2D6-mediated metabolism.Keywords
This publication has 28 references indexed in Scilit:
- A micromethod for quantitation of debrisoquine and 4-hydroxydebrisoquine in urine by liquid chromatographyBrazilian Journal of Medical and Biological Research, 2000
- Mutations in the hepatocyte nuclear factor-4α gene in maturity-onset diabetes of the young (MODY1)Nature, 1996
- P450 superfamily: update on new sequences, gene mapping, accession numbers and nomenclaturePharmacogenetics, 1996
- Antihyperglycaemic Agents Drug Interactions of Clinical ImportanceDrug Safety, 1995
- Recent Developments in Hepatic Drug OxidationClinical Pharmacokinetics, 1990
- Effects of Rat Bile Infusion on Renal Function in RatsKidney and Blood Pressure Research, 1990
- Human debrisoquine 4-hydroxylase (P450IID1): cDNA and deduced amino acid sequence and assignment of the CYP2D locus to chromosome 22Genomics, 1988
- The polymorphic 4-hydroxylation of debrisoquine in a Saudi arab populationXenobiotica, 1980
- The metabolism of [14C]‐debrisoquine in man.British Journal of Clinical Pharmacology, 1979
- Metabolism of Debrisoquine Sulphate in Rat, Dog and ManXenobiotica, 1976