Structure-function relationships of inhibition of human cytochromes P450 1A1, 1A2, 1B1, 2C9, and 3A4 by 33 flavonoid derivatives.

Article Details

Citation

Shimada T, Tanaka K, Takenaka S, Murayama N, Martin MV, Foroozesh MK, Yamazaki H, Guengerich FP, Komori M

Structure-function relationships of inhibition of human cytochromes P450 1A1, 1A2, 1B1, 2C9, and 3A4 by 33 flavonoid derivatives.

Chem Res Toxicol. 2010 Dec 20;23(12):1921-35. doi: 10.1021/tx100286d.

PubMed ID
21053930 [ View in PubMed
]
Abstract

Structure-function relationships for the inhibition of human cytochrome P450s (P450s) 1A1, 1A2, 1B1, 2C9, and 3A4 by 33 flavonoid derivatives were studied. Thirty-two of the 33 flavonoids tested produced reverse type I binding spectra with P450 1B1, and the potencies of binding were correlated with the abilities to inhibit 7-ethoxyresorufin O-deethylation activity. The presence of a hydroxyl group in flavones, for example, 3-, 5-, and 7-monohydroxy- and 5,7-dihydroxyflavone, decreased the 50% inhibition concentration (IC50) of P450 1B1 from 0.6 muM to 0.09, 0.21, 0.25, and 0.27 muM, respectively, and 3,5,7-trihydroxyflavone (galangin) was the most potent, with an IC50 of 0.003 muM. The introduction of a 4'-methoxy- or 3',4'-dimethoxy group into 5,7-dihydroxyflavone yielded other active inhibitors of P450 1B1 with IC50 values of 0.014 and 0.019 muM, respectively. The above hydroxyl and/or methoxy groups in flavone molecules also increased the inhibition activity with P450 1A1 but not always toward P450 1A2, where 3-, 5-, or 7-hydroxyflavone and 4'-methoxy-5,7-dihydroxyflavone were less inhibitory than flavone itself. P450 2C9 was more inhibited by 7-hydroxy-, 5,7-dihydroxy-, and 3,5,7-trihydroxyflavones than by flavone but was weakly inhibited by 3- and 5-hydroxyflavone. Flavone and several other flavonoids produced type I binding spectra with P450 3A4, but such binding was not always related to the inhibitiory activities toward P450 3A4. These results indicate that there are different mechanisms of inhibition for P450s 1A1, 1A2, 1B1, 2C9, and 3A4 by various flavonoid derivatives and that the number and position of hydroxyl and/or methoxy groups highly influence the inhibitory actions of flavonoids toward these enzymes. Molecular docking studies suggest that there are different mechanisms involved in the interaction of various flavonoids with the active site of P450s, thus causing differences in inhibition of these P450 catalytic activities by flavonoids.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
FlavoneCytochrome P450 1B1ProteinHumans
Unknown
Not AvailableDetails
GenisteinCytochrome P450 1B1ProteinHumans
Unknown
Not AvailableDetails
NaringeninCytochrome P450 1B1ProteinHumans
Unknown
Not AvailableDetails
QuercetinCytochrome P450 1B1ProteinHumans
Unknown
Not AvailableDetails