Table 3

Effect of glabridin on the catalytic activity and P450 reduced CO spectrum of P450s 3A4 and 2B6

P450 Incubation Conditions	% Activity Remaining		% CO Spectrum Remaining
P450 Incubation Conditions	0 min	15 min	30 min	0 min	15 min	30 min
3A4 − Glabridin ⁺NADPH	100	97 ± 2	98 ± 4	100	86 ± 2	95 ± 7
3A4 ⁺ Glabridin − NADPH	94 ± 3	95 ± 3	79 ± 13	99 ± 2	93 ± 3	87 ± 6
3A4⁺ Glabridin ⁺ NADPH	94 ± 3	36 ± 1	37 ± 15	99 ± 2	58 ± 1	85 ± 6
2B6 − Glabridin ⁺NADPH	100		100
2B6 ⁺ Glabridin − NADPH	83 ± 17		102 ± 10
2B6 ⁺ Glabridin ⁺NADPH	83 ± 17		102 ± 10

P450s 3A4 and 2B6 were reconstituted with reductase and lipid, incubated with 10 or 30 μM glabridin, respectively, and evaluated for 7BFC activity and P450-reduced CO spectra as described underExperimental Procedures. The data shown represents the mean and standard deviation from three experiments.