Study of coumarin metabolism by Chinese hamster lung fibroblasts expressing a human cytochrome P450 using ¹H-nmr

Abstract

1. Human cytochrome P450 2A6 is expressed in Chinese hamster lung fibroblasts. The isozyme hydroxylates coumarin at the 7-position.

2. Metabolism of coumarin in these lung fibroblasts was monitored using ¹H-nmr. Media samples were taken from cells grown in flasks and also in a fluidized bed bioreactor. In each case 7-hydroxycoumarin was readily observable by nmr in crude extracts of the medium.

3. The rate of formation of 7-hydroxycoumarin observed in the acute bioreactor experiments on a per cell basis was found to be much higher than that obtained under chronic monolayer conditions, and correlated with glucose consumption rates.