Effects Of Compound Kushen Injection On Pharmacokinetics Parameters Of Gemcitabine In Rats And Effects Of Both Drugs On Cytochrome P450 Enzymes In Rats

Objective:In recent years,the clinical application of the combination useage of traditional Chinese medicine and drugs for the treatment of cancer cases are so commen,however,the potention herb-drug interactions are not concerned in nowdays.Thus,the purpose of this topic is to explore whether the CKI and gemcitabine hydrochloride injection could be altered in the pharmacokinetic aspect,and their effects on rat liver Cytochrome P450 Enzymes.Thus,we could provide some reference for CKI and gemcitabine combination.Methods:1.The analysis method of establishing HPLC method for determining the gemcitabine in rats plasma.2.The experiment about the effects of single dose CKI on pharmacokinetic parameters of gemcitabine in rats:randomly divided 24 healthy male SD rats into one control group and three dose groups respectively injected with CKI at low,medium and high dose.The control group rats were injected with gemcitabine directly,three dose groups rats were injected with gemcitabine 5 min after low,medium and high-dose CKI.Collect orbital blood from the rats in the four groups in the same 13time points,determined the plasma concentration of gemcitabine in the blood samples by HPLC method,calculated the pharmacokinetic parameters with DAS2.0 software,and made statistical analysis.3.The experiment about the effects of multi-dose CKI on pharmacokinetic parameters of gemcitabine in rats:the control group rats were injected with saline for 10 days and injected with gemcitabine 5 min after saline on the last day,three dose groups rats were injected with low,medium and high-dose CKI for 10 days and injected with gemcitabine 5 min after CKI on the last day.Other parts of this experiment were the same with the single dose experiment.4.The biological sample analysis method of establishing UPLC-MS/MS method for determining the probe substrates corresponding to the six kinds of metabolic enzymes in rats,namely,Cyp1a2,Cyp2b1,Cyp2d2,Cyp2c6,Cyp3a1,and Cyp2c11.5.The experiment about the effects of single dose CKI combined with gemcitabine on Cyp450 enzyme activity of rats:randomly divided 24 healthy male SD rats into one control group and three dose groups respectively injected with CKI at low,medium and high dose.The control group rats were injected with probe drug directly and three dose groups rats were injected with gemcitabine 5 min after low,medium and high-CKI,and then make probe drug injection at caudal veins.Collect orbital blood from the rats in the four groups in the same 12 time points,determined the plasma concentration of 6 probe drugs in the blood samples by UPLC-MS/MS method,calculated the pharmacokinetic parameters with DAS2.0 software,and made statistical analysis.6.The experiment about the effects of multi-dose CKI combined with gemcitabine on Cyp450 enzyme activity of rats:The control group rats were injected with saline for 10 days and injected with probe drugs 5min after saline on the last day,three dose groups rats were injected with low,medium and high-dose CKI for 10 days and injected with gemcitabine 5 min after CKI on the last day,and then make probe drug injection at caudal veins.Other parts of this experiment were the same with the single dose experiment.Results:（1）The pharmacokinetic process of gemcitabine in SD rats conformed to the two-compartment model fitting,and there was no significant statistical difference in the main pharmacokinetic parameters of single-dose CKI group,such as the half-life period(t_1/2),overall elimination rate（CL）,drug concentration-time curve and etc.Compared with the control group,there were statistical differences in some pharmacokinetic parameters of high dose CKI group in the multi-dose experiment,for instance,the area under drug concentration-time curve rose,and the Mean residence time（MRT）extended.（2）In the experiment about the effects of CKI combined with gemcitabine on Cyp450enzyme activity of rats,the MRT and t_1/2/2 of six probe drugs were shortened in a single-dose experiment,and the AUC of bupropion and dextromethorphan were reduced.In the multi-dose experiment,the AUC of bupropion,dextromethorphan and diclofenac increased,and CL decreased;the MRT and t_1/2/2 of the other five probe drugs except midazolam extended.Conclusion:Single dose CKI had no significant effect on the pharmacokinetic parameters of gemcitabine hydrochloride injection in rats.Multiple doses of high-dose CKI will increase plasma concentration of gemcitabine and prolong the residence time.Single-dose CKI combined with gemcitabine had partial induction action on Cyp2b1and Cyp2d2 enzymes;multi-dose CKI combined with gemcitabine had inhibition action on Cyp2d2 and Cyp2c6,and partial inhibition action on Cyp1a2,Cyp2b1,and Cyp2c11.This showed when the CKI was used with gemcitabine at the same time,the potential drug interactions might occur.In clinical practice,the dose of CKI should be considered according to the patient’s condition.Also this suggested that the combination of CKI and gemcitabine may have potential interactions with other drugs metabolized by this metabolic enzyme,providing reference for clinical medication.The combined use of CKI and gemcitabine is worth further study in the metabolic aspect in the later period.