Borneol is a traditional Chinese medicine. In the past few years, many studies showed that borneol can improve the bioavailability of other drugs, promoting drugs to cross the blood-brain barrier, so the potential drug interactions between borneol and other medicines have attracted great attention, but the influence of borneol to CYP450 and its isoforms are rarely reported. In this research, male Wistar rats were orally administered by borneol for 7 days, then the mRNA and protein expression and the activities of CYP2D were detected, we also compared the pharmacokinetic parameters of CYP2D's specific substrate between control group and borneol group. The results show that borneol (33, 100 and 300 mg x kg(-1) x d(-1)) have no significant effect on CYP2D, while the activites of CYP2D increased 1.71, 1.97 and 2.89 times comparing to the control group. At the same time, borneol (300 mg x kg(-1) x d(-1)) caused the C(max) decreased 10.6% (P > 0.05), AUC(0-∞) decreased 27.5% (P < 0.01), CL/F increased 41.1% (P < 0.01), V(z)/F increased 23.1% (P > 0.05) of dextromethorphan. Our data provided that borneol speed up dextromethorphan's elimination in vivo. Since the activity of CYP2D can be induced by borneol, the metabolic interactions might happen when borneol and the substrate drug CYP2D are used together.
Animals ; Aryl Hydrocarbon Hydroxylases ; metabolism ; Blood-Brain Barrier ; Bornanes ; pharmacology ; Cytochrome P-450 Enzyme Inducers ; pharmacology ; Dextromethorphan ; Drug Interactions ; Liver ; drug effects ; enzymology ; Male ; Medicine, Chinese Traditional ; RNA, Messenger ; Rats ; Rats, Wistar

The regulation mechanism of arecoline on rat hepatic CYP2E1 was studied in vivo. After oral administration of arecoline hydrobromide (AH; 4, 20 and 100 mg x kg(-1) x d(-1)) to rats for one week, the hepatic CYP2E1 mRNA level remained unchanged, but the hepatic CYP2E1 protein content was dose-dependently increased. Additionally, although the hepatic CYP2E1 activity was induced by AH treatment, the induction was attenuated with the increase in dosage. The results indicate that the effect of arecoline on rat hepaticdoes not involve transcriptional activation of the gene, but largely involves the stabilization of CYP2E1 protein against degradation or increased efficiency of CYP2E1 mRNA translation, and additionally involve the post- ranslational modification of CYP2E1 protein. Furthermore, the CYP2E1 response is fairly equal among the different species, the induction of rat hepatic CYP2E1 by arecoline suggests that there is a risk of metabolic interaction among the substrate drugs of CYP2E1 in betel-quid use human.
Animals ; Arecoline ; pharmacology ; Cytochrome P-450 CYP2E1 ; metabolism ; Cytochrome P-450 CYP2E1 Inducers ; pharmacology ; Humans ; Liver ; drug effects ; metabolism ; RNA, Messenger ; Rats