Effects Of Pu-erh Tea Aqueous Extract On The Cytochrome P450 Enzymes In Rats

Objective:Pu-erh tea,a well-known traditional Chinese tea,is derived from leaves of large-leaf tea species,Camellia sinensis var.Assamica in Yunnan province of China with special processing and the quality characteristics,becoming increasingly popular.The reports indicated that food-drug interactions may result in the absorption reducing or the excretion increasing of drugs,and even therapy failure,antibiotic resistance and increased incidence.The aim of the present study was to evaluate the potential effects of Pu-erh tea aqueous extract(PTAE)on the activity of CYP1A2,CYP2E1 and CYP3A in rats with cocktail approach;the influence of CYP m RN A was also studied.Discussing the interaction between Pu-erh tea and drugs metabolized by C YP,the experimental evidence is provided for safe and beneficial consuming Pu-erh tea in clinical practice.Methods:The substract drugs are theophylline,dapsone and chlorozoxazone for CYP1A2,CYP3A and CYP2E1 with“Cocktail”approach to develop simultaneous determination of three kinds of probe drugs in serum by UP LC.Chromatographic separation was achieved on an ACQUITY UPLC B EH Shield C18。The mobile phase composed of methanol and 0.1%aqueous-formic acid at a flow rate of 0.3 mL·min-1 and detection wave-length was set at 280 nm.We evaluated the effect of PTAE on CYP450 enzymes activity in rats by pharmacokinetic parameters of theophylline,daps one and chlorozoxazone.In addition,real time reverse transcription polymerase chain reaction(RT-PCR)was performed to determine the effects of PTAE on the mRNA expression of CYP1A2,CYP2E1 and CYP3A1 in rats.Male Wist a r rats were randomly divided into 3 groups:blank control group(BCG),PTAE low dosage group(PLG)and high dosage group(PHG),which were given water and a 0.5 g·k g-1,1.5 g·kg-1 dosage of PTAE,by oral administration for seven consecutive days.One part was given a“C ocktail”probe solution mixed with three probe drugs each group on the eighth day.Then UPLC was used to test the blood concentration of probes and related pharmacokinetic parameters were calculated by DAS 3.0.Major pharmacokinetic parameters of PTAE group and blank group were evaluated by by oneway ANOVA.The other part,the rats were sacrificed to collect the livers and determined the expression of CYP1A2,CYP2E1 and CYP3A mRNA.Results:1.A UPLC method had been established which could simultaneously determine the concentrations of theophylline,dapsone and chlorozoxazone in rats plasma.It could separate the three drugs effectively and the UPLC method was formally validated and showed good performances in terms of linearity,sensitivity,precision,accuracy and recovery.2.Th e effect of Pu-erh tea aqueous extract on the pharmacokinetic of probe drugs:Compared with control group,the T1/2 for theophylline of PHG was significantly decreased(P<0.0 5),indicated that the metabolism of theophylline was accelerated,while the other pharmaco kinetic parameters(Tmax,Cmax,AU C024h,AUC0-∞ and CL/F)of theophylline did not have been significantly influenced(P>0.0 5).The tmax for dapsone of PHG was significantly decreased(P<0.0 5),while the other pharmacokinetic parameters(T1/2,Cmax,AUC0-24h,AUC0-∞ and CL/F)of dapsone did not have been significantly influenced(P>0.0 5),it may be related with intestinal absorption.In addition,the pharmacokinetic parameters(T1/2,Tmax,Cmax,A U C 024h,AUC0-∞ and CL/F)chlorzoxazone had no significant change(P>0.0 5).3.Effects of Pu-erh tea aqueous extract on mRNA expression of C Y P enzymes:Compared with control group,CYP1A2 expression had increased in PHG(P>0.0 5),Meanwhile,the m RN A expression level of CYP3A1 was increased in PLG and decreased in PHG,while,there was no significant differences(P>0.0 5).Almost no differences in the m RN A expression level of CYP2E1 was observed.Conclusion:Our results indicated that the high dosage PTAE had the potential to induce CYP1A2 activity in PHG,and no potential effect on the activity of CYP3A and CYP2E1 in rats.Futhermore,PTAE had increased the expression of CYP1A2 in PHG and CYP3A in PLG,decreased the expression of CYP3A in PHG,it indicated that PTAE effected the gene through the translation.We concluded that repeated Pu-erh tea aqueous extract administration is not likely to result in significant effects on drugs metabolized by CYP enzymes at the recommended daily intake of Pu-erh tea aqueous extract.