Lee, H.-S. Jin, C. Park, J. Kim, D.-H. 2024-01-21T22:11:04Z 2024-01-21T22:11:04Z 2021-09-02 1994-01 1039-9712 https://pubs.kist.re.kr/handle/201004/145913 7,8-Benzoflavone(ANF) is a potent in vitro inhibitor of CYP1A2 but is an in vitro activator of CYP3A4. We have investigated the inhibition of caffeine 3-demethylation by metabolites of ANF as well as ANF by human liver microsomes. ANF was the most potent among all the compounds tested. Metabolites of ANF with dihydrodiol substitution at positions 5,6 or 7,8 showed less inhibitory activity. These results suggest that ANF lies in the most appropriate orientation to the active site of CYP1A2. The activation of CYP3A4 enzyme activities by ANF and its metabolites was also investigated. Testosterone 6β-hydroxylation mediated by CYP3A4 was stimulated by ANF and metabolites with substitutions at positions 5,6 or 7,8. Hydroxy ANF metabolites, however, decreased the testosterone 6β-hydroxylation. English alpha naphthoflavone benzoflavone derivative caffeine cytochrome p450 testosterone animal tissue article controlled study demethylation enzyme activation enzyme regulation human human tissue hydroxylation liver microsome liver microsome metabolism nonhuman structure activity relation Animal Benzoflavones Cytochrome P-450 CYP1A2 Cytochrome P-450 Enzyme System Enzyme Activation Human Oxidoreductases Rabbits Steroid Hydroxylases Support, Non-U.S. Gov&apos t Modulation of cytochrome P450 activites by 7,8-benzoflavone and its metabolites Article 1 Biochemistry and Molecular Biology International, v.34, no.3, pp.483 - 491 Biochemistry and Molecular Biology International 34 3 483 491 scopus 2-s2.0-0027970187 Article alpha naphthoflavone benzoflavone derivative caffeine cytochrome p450 testosterone animal tissue article controlled study demethylation enzyme activation enzyme regulation human human tissue hydroxylation liver microsome liver microsome metabolism nonhuman structure activity relation Animal Benzoflavones Cytochrome P-450 CYP1A2 Cytochrome P-450 Enzyme System Enzyme Activation Human Oxidoreductases Rabbits Steroid Hydroxylases Support, Non-U.S. Gov&apos t