Effect And Mechanism Of Wuzhi Tablet On Pharmacokinetics Of Voriconazole In Rats

At present,recipients of solid organ transplantation are at high risk of developing invasive fungal disease.Several invasive fungal agents widely used therapeutically.Voriconazole is recommended as the first-line agent since its wide antifungal spectrum.Tacrolimus is a potent immunosuppression agent for the prevention in solid organ transplantation patient.Wuzhi tablet(WZ)was used to protect solid organ transplantation patient from chronic hepatitis and liver dysfunction in china.The coadministration of voriconazole,tacrolimus and WZ is widely prescribed for solid organ transplantation patients in china.To explore the potential drug-drug interaction of voriconazole,we investigate the effect of WZ on the pharmacokinetic and relevant mechanism in rat.Our study can act as the guideline of rational use of voriconazole in clinic.Objective: To study the effect of WZ on the pharmacokinetics of voriconazole in rats and the mechanism.Methods: 1.The LC-MS / MS method for the determination of voriconazole in plasma was established and the specificity,matrix effect,sensitivity,recovery and stability of the method were investigated.2.SD rats were randomly divided into two groups: the control group was treated with water.The example group was treated with Wuzhi tablets/Schinsandrins.The plasma was collected and the concentration of voriconazole was measured.Pharmacokinetic software was used to gain Pharmacokinetic datas.3.In the Caco-2 monolayer cell membrane bi-directional transport experiment,a layer of Caco-2 cells was deposited on the bottom of the ?A? plate of the Transwell plate.Voriconazole and different concentrations of Wuzhi extract/ Schinsandrins were added to the ?A? plate or ?B2?of the Transwell plate.The control group was added to the ?A? plate or ?B2?of the Transwell plate with Voriconazole and the incubation was started.After the incubation,the Apparent Permeability Coefficient(Papp)of voriconazole bi-directional transport was calculated,and the efflux rate was calculated by Papp.4.NADPH coenzymes,specific substrates,specific inhibitors or the extra of Wuzhi tablet /schisandrins were added to human liver microsomes before the example.The amount of metabolites produced in each group was determined by HPLC-MS.The inhibitory rate was calculated by comparing the amount of metabolites of different groups.Results: 1.A LC-MS/MS method was developed and validated.Linearity was assessed with a correlation coefficient of r2 > 0.997.The recovery of the method was 87.2%-103.2%.The intra-and inter-batch precision was less than 15% for all quality control(QC)samples.The validated LC-MS/MS method was rapid and sensitive with high selectivity and precision.2.After coadministration of a single oral dose of WZ(0.25 g/kg),the AUC of intravenous dose of voriconazole was increased 80.2%(p<0.05).After long-term treatment of WZ(0.25 g/kg)to rats for 14 days,the AUC of intravenous dose of voriconazole was increased 66.4%(p<0.05).Cpmpared with control group,after a single oral dose of schisandrol B(10mg/kg)and Schisantherin A(10mg/kg)to rats,the AUC of oral dose voriconazole increased 47.3%(p<0.05)and 44.3%(p<0.05)compared to that of control group by oral administration.The AUC of intravenous dose voriconazole increased 37.4%(p<0.05)and 47.5%(p<0.05)compared to that of control group by intraveneous injection.After 14 days treatment of schisandrol B(10mg/kg)and Schisantherin A(10mg/kg)to rats,the AUC of oral dose voriconazole increased30.1%(p<0.05)and 22.5%(p<0.05)compared to that of control group by oral administration.The AUC of intravenous dose voriconazole increased 29.3%(p<0.05)and 36.5%(p<0.05)compared to that of control group by intraveneous injection.3.Cpmpared with control group,the efflux ratio of voriconazole decreased from 3.7 to 0.7(p<0.05)with WZ pretreated.The efflux ratio of voriconazole decreased from 3.7 to 0.6(p<0.05)and 1.0(p<0.05)with Schisandrin A and Schisandrol B.4.Wuzhi tablets/Schinsandrins showed inhibition on nine CYP450.The IC50 of Wuzhi tablet on CYP2C19 is 625 ?g/m L and the IC50 of Wuzhi tablet on CYP3A4 is less than 39.1?g/m L;the IC50 of Schisandrin A on CYP2C19 is less than 50?M;the IC50 of Schisandrol B on CYP3A4 is less than 6.25?M.Conclusion: 1.The LC-MS/MS method was good enough to determine the concentration of voriconazole in our study.2.The whole blood concentration and AUC of voriconazole was increased when coadministered with WZ/ Schinsandrins.3.Wuzhi tablet may have a certain effect on the absorption of voriconazole in the small intestine.4.The study showed that Wuzhi tablet effect the the pharmacokinetics of voriconazole by inhibiting the activity of CYP2C19.