title: Danazol Inhibits Cytochrome P450 2J2 Activity in a Substrate-independent Manner.
abstract: Cytochrome P450 2J2 (CYP2J2) is an enzyme responsible for the metabolism of endogenous substrates including arachidonic acid, as well as therapeutic drugs such as albendazole, astemizole, ebastine, and terfenadine. Selective inhibitors of CYP2J2 are essential for P450 reaction phenotyping studies. To find representative CYP2J2 index inhibitors, we evaluated the inhibitory potential of danazol, hydroxyebastine, telmisartan, and terfenadone against CYP2J2 activity for four representative CYP2J2 substrates (albendazole, astemizole, ebastine, and terfenadine) using recombinant CYP2J2. Of these four CYP2J2 inhibitors, danazol strongly inhibited CYP2J2-mediated albendazole, astemizole, ebastine, and terfenadine metabolism in a substrate-independent manner, with IC50 values of 0.05, 0.07, 0.18, and 0.34 μM, respectively. Danazol noncompetitively inhibited CYP2J2-mediated astemizole O-demethylation activities with a Ki value of 0.06 μM. Terfenadone strongly inhibited CYP2J2-mediated albendazole, astemizole, and terfenadine metabolism (IC50 < 0.21 μM), whereas it showed weak inhibition against CYP2J2-catalyzed ebastine hydroxylase activity (IC50 = 6.04 μM). Telmisartan had no inhibitory effect on CYP2J2-mediated ebastine and terfenadine hydroxylation (IC50 > 20 μM). Taken together, these data suggest that danazol may be used as a CYP2J2 index inhibitor in reaction phenotyping studies.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, South Korea.
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Lee
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, South Korea.
authors.forename: Zhexue
authors.initials: Z
authors.lastname: Wu
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, South Korea.
authors.forename: Jong Cheol
authors.initials: JC
authors.lastname: Shon
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, South Korea dstlkh@knu.ac.kr.
authors.forename: Kwang-Hyeon
authors.initials: KH
authors.lastname: Liu
mesh_terms: D000090762:Cytochrome P-450 CYP2J2; D065607:Cytochrome P-450 Enzyme Inhibitors / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D003613:Danazol / Q000494:pharmacology*; D004965:Estrogen Antagonists / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D004364:Pharmaceutical Preparations / Q000378:metabolism; D010641:Phenotype; D011994:Recombinant Proteins; D013379:Substrate Specificity
chemical_list: C000717350:CYP2J2 protein, human; D065607:Cytochrome P-450 Enzyme Inhibitors; D004965:Estrogen Antagonists; D004364:Pharmaceutical Preparations; D011994:Recombinant Proteins; D003577:Cytochrome P-450 Enzyme System; D000090762:Cytochrome P-450 CYP2J2; D003613:Danazol