Coumarin metabolism by recombinant P450 enzymes
| P450 | 3-Hydroxycoumarin Formation | o-Hydroxyphenylacetaldehyde Formation |
|---|---|---|
| nmol/min/nmol P450 | ||
| Human | ||
| CYP1A1 | 0.271-a | 6.26 |
| CYP1A2 | 0.10 | 1.96 |
| CYP2E1 | 0.17 | 3.35 |
| CYP3A4 | 0.68 | N.D. |
| CYP2A6 | N.D. | N.D. |
| Rat | ||
| CYP1A1 | 0.44 | 3.69 |
| CYP1A2 | 0.38 | 22.2 |
Microsomal preparations of SF9 cells expressing human CYP1A1 (reductase/P450, 18:1), CYP1A2 (reductase/P450, 7:1), CYP2E1 (reductase/P450, 3:1, b5/P450, 2:1), CYP3A4 (reductase/P450, 7:1, b5/P450, 5:1), CYP2A6 (reductase/P450, 1:1), and rat CYP1A1 (reductase/P450, 2:1) and CYP1A2 (reductase/P450, 2:1) were incubated with 100 μM coumarin, and 3-hydroxycoumarin or o-hydroxyphenylacetaldehyde formation was quantitated by liquid chromatography-mass spectrometry or gas chromatography coupled with flame ionization detection, respectively.
N.D., not detected; b5, cytochromeb5.
↵1-a Values are the average of duplicate determinations.