[Effects on the activities and mRNA expression of CYP3A in rat's liver by four kinds of extracts from anti-cancer Traditional Chinese Medicines].

OBJECTIVE

To study the effects of four kinds of extracts from anti-cancer Taditional Chinese Medicines on the activity and mRNA expression of CYP3A in rat's liver.

METHODS

Rat's liver microsomal cytochrome P450 and CYP3A isoemzymes--erythromycin N-demethylase(ERD) activities were determined by UV chromatography, the mRNA expression levels of CYP3Al and CYP3A2 were detected by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

Extracts of Rhizoma Curcumae, Rhizoma Atractylodes and Rhizoma Atractylodes Macrocaphalae markedly increased the P450 content of liver microsomes and induced the enzyme activity of CYP3A, but extract of Poria cocos did not. At the mRNA level, extracts of Rhizoma Curcumae, Rhizoma Atractylodes Lanceae and Rhizoma Atractylodes Macraphalae induced the expression of CYP3A1, but extract of Poria cocos did not. The expression of CYP3A2 were induced by extracts of Rhizoma Curcumae and Rhizoma Atractylodes Lanceae, but extracts of Rhizoma Atractylodes Macrocaphalae and Poria cocos were found of remarkable inhibition of the mRNA expression of CYP3A2.

CONCLUSION

Extracts of Rhizoma Curcumae, Rhizoma Atractylodes Lanceae and Rhizoma Atractylodes Macrocaphalae can regulate CYP3A on the levels of enzyme activity and mRNA expression, but Poria cocos extract only regulated CYP3A on the level of mRNA expression, possibly by affecting the metabolism of other drugs in the body.