Quantifying four-probe metabolites in a single UPLC-MS/MS run to explore the effects of cooked rhubarb on cytochrome P450 isozymes.

BACKGROUND

Cytochrome P450 (CYP) enzymes primarily account for the oxidation of xenobiotics. A single run UPLC-MS/MS method was developed to simultaneously detect four metabolites from a probe cocktail to investigate four CYP isozymes. Paracetamol was detected to investigate CYP1A2, 4-hydroxytolbutamide for CYP2C6, 6-hydroxychlorzoxazone for CYP2E1 and dehydronifedipine for CYP3A1. 6-hydroxychlorzoxazone was detected in ESI-negative mode, while the other three were detected in ESI-positive mode.

RESULTS

The method was rapid (2.5 min) and validated to be specific, accurate and precise. It was successfully applied to evaluate the effects of cooked rhubarb on the activities of the four isozymes in rat microsomes. Cooked rhubarb inhibited the activity of CYP2C6 but induced both CYP2E1 and CYP3A1.

CONCLUSION

This convenient UPLC-MS/MS method was applicable. It could improve the efficiency of future studies estimating the influence of herbs, herbal products or drug entities on the activities of CYP1A2, CYP2C6, CYP2E1 and CYP3A1.