Regulation of CYP2C19 expression by estrogen receptor alpha: implications for estrogen-dependent inhibition of drug metabolism.

Article Details

Citation

Copy to clipboard

Mwinyi J, Cavaco I, Pedersen RS, Persson A, Burkhardt S, Mkrtchian S, Ingelman-Sundberg M

Regulation of CYP2C19 expression by estrogen receptor alpha: implications for estrogen-dependent inhibition of drug metabolism.

Mol Pharmacol. 2010 Nov;78(5):886-94. doi: 10.1124/mol.110.065540. Epub 2010 Jul 30.

PubMed ID

20675569 [ View in PubMed

]

Abstract

Cytochrome P4502C19 (CYP2C19) is an important drug-metabolizing enzyme involved in the biotransformation of, for example, proton pump inhibitors and antidepressants. Several in vivo studies have shown that the CYP2C19 activity is inhibited by oral contraceptives, which can cause important drug interactions. The underlying molecular mechanism has been suggested to be competitive inhibition. However, the results presented here indicate that estradiol derivatives down-regulate CYP2C19 expression via estrogen receptor (ER) alpha, which interacts with the newly identified ER-binding half site [estrogen response element (ERE)] at the position -151/-147 in the CYP2C19 promoter. In gene reporter experiments in Huh-7 hepatoma cells, the activity of the luciferase construct carrying a 1.6-kb long CYP2C19 promoter fragment cotransfected with ERalpha was down-regulated upon treatment with 17beta-estradiol (EE) or 17alpha-ethinylestradiol (ETE) at half-maximum concentrations of 10(-7) and 10(-8) M, respectively. Mutations introduced into the ERE half site -151/-147 significantly inhibited these ligand-dependent effects. Electrophoretic mobility shift assays and quantitative chromatin immunoprecipitation experiments revealed that estrogen receptor alpha binds to this element. A significant suppression of CYP2C19 transcription by female sex steroids was confirmed by reverse transcription polymerase chain reaction after hormonal treatment of human hepatocytes. Inhibition experiments using a stable human embryonic kidney 293 CYP2C19 cell line revealed competitive inhibition at much higher concentrations of EE and ETE compared with those required for transcriptional inhibition. These results indicate that both EE and ETE inhibit CYP2C19 expression via an ERalpha-dependent regulatory pathway, thus providing a new insight into the molecular mechanism behind the inhibitory effect of oral contraceptives on CYP2C19 activity.

DrugBank Data that Cites this Article

Drug Enzymes

Drug	Enzyme	Kind	Organism	Pharmacological Action	Actions
Estradiol	Cytochrome P450 2C19	Protein	Humans	Unknown	Substrate	Details