Identification Of Components Of Astragalus, Radix Angelicae Sinensis And Radix Angelicae Sinensis That Enter The Blood And Their Effects On The Pharmacokinetics Of Levofloxaci

The spread of antibiotic-resistance bacteria was attracted broad attention in the world in recent years.How to reduce risks of multiple-resistant bacteria and pan-resistant bacteria infection are the important and difficult points of clinical research.Proper use of antibiotics could avoid the occurrence of antibiotic-resistance bacteria.It will be crucial to improve the prognosis of patients.Qi-gui-yin（QGY）is composed of five herbal medicines,Astragalus membranaceus（Fisch.）Bge.,Angelica sinensis（Oliv.）Diels,Lonicera japonica Thunb.,and Artemisia annua L.,Polygonum cuspidatum Sieb.et Zucc.It can be used for the treatment of multiple-resistant bacteria infection with antibiotics such as Levofloxacin（LVFX）and can delay or even reverse bacterial drug resistant.Howere,there are few studys on QGY combined with antibiotics in vivo course and pharmacokinetics in model animals.This study identified the compounds in ICR mice plasma after oral administration of QGY extract to investigate the effective constituents in vivo.A quantitative method was developed for LVFX by ultra performance liquid chromatography mass spectrometry（UPLC-MS/MS）in mice plasma.Based on the above research,the metabolism process of two medicines（QGY and LVFX）combination in mice model of pneumonia infected by Pseudomonas aeruginosa were preliminarily discussed according to the pharmacokinetic parameters.The main research contents and results are as follows.1.Identification of the absorbed components in mice plasma after oral administration of Qi-gui-yin extract by LC-ESI-HR-MS/MS.The study was performed using HPLC-ESI-LTQ-Orbitrap to identify the chemical constituents of mice plasma samples obtained after oral administration of the extract.Identification and structural elucidation of the compounds in dosed plasma were performed by comparing their retention time and MSn spectra with those of blank plasma and reference compounds as well as reported data in references.27 drug-induced compounds were screened from mice plasma.21 of them were identified including 15 prototype compounds and 6 metabolites（glucosidation or isomerization）.The result indicated that prototype,glucosidation and isomerization were the major pathways that Qi-gui-yin extract absorbed in blood.It is a reliable and sensitive method for the analysis of absorbing chemical constituents of mice plasma.It also may provide useful information for further understanding of the action mechanism and pharmacological actions of Qi-gui-yin extract.2.Determination of LVFX by UPLC-MS/MS in mice plasma.To establish a rapid and sensitive ultra performance liquid chromatography mass spectrometry（UPLC-MS/MS）method for the determination of concentration of LVFX in mice plasma.The LVFX and the internal standard（Ciprofloxacin hydrochloride,CPFX）were separated on an Acquity UPLC? BEH C18 chromatography column（2.1 mm × 100 mm I.D.,1.7μm）using gradient elution with a mobile phase of acetonitrile and 0.1%formic acid in water at a flow rate of 0.4 mL/min.The detection was performed on a Xevo triple quadrupole tandem mass spectrometer by multiple reaction monitoring（MRM）mode to monitor the precursor-to-product ion transitions of m/z 362.24→m/z 318.17 for LVFX and m/z 332.23→m/z 288.16 for CPFX（IS）using a positive electrospray ionization interface.The regression equations showed good linear relationships within their respective linear ranges.A simple,rapid,sensitive,and accurate method for the determination of the concentration of LVFX in mice plasma was developed and validated.3.Comparative pharmacokinetic study on LVFX and LVFX combined with QGY in mice plasma.（1）Comparative pharmacokinetic study on LVFX in normal mice plasma and model of pneumonia mice infected by Pseudomonas aeruginosa plasma.After validation,this method was successfully applied to a pharmacokinetic study.We compared the pharmacokinetic behaviors of LVFX in normal mice（group A）and mice model of pneumonia infected by Pseudomonas aeruginosa（group B）.Pharmacokinetic parameters were performed using DAS 3.0,and the statistical analysis was performed by SPSS 17.0.The result indicated that the parameters(AUC0-∞、AUC0-t、CL、C_max)of LVFX in normal mice（group A）were different from those of mice model of pneumonia infected by Pseudomonas aeruginosa（group B）,and the difference was significant（P<0.05）.Mice model of pneumonia infected by Pseudomonas aeruginosa is closer to the pathological state of drug in the body’s absorption,distribution,metabolic and excretion process（ADME）.Therefore,this model could apply to pharmacokinetic study on LVFX combined with QGY in mice plasma.（2）Comparative pharmacokinetic study on LVFX which was combined with QGY in model of pneumonia mice infected by Pseudomonas aeruginosa plasma.UPLC-MS/MS method was used to study the effect of QGY on pharmacokinetic in model of pneumonia mice infected by Pseudomonas aeruginosa plasma of LVFX.model of pneumonia infected by Pseudomonas aeruginosa mices were randomly assigned to three groups:single LVFX group（group B）,LVFX and QGY group（two drugs were given simultaneously,group C）,LVFX and QGY group（QGY first,LVFX were given after 30min,group D）.The result indicated that the parameters（AUC,AUMC）of group C and group D were bigger than that in group B.The difference was significant（P<0.05）.The parameters of MRT in group C was bigger than that in group B,and the difference was significant（P<0.05）suggesting that drug combination can prolong the mean retention time.The drug combination simultaneously（group C）can prolong the T_max,suggesting that QGY can decelerate rate of absorption of LVFX.The results of group C and group D show that:LVFX administrated in combination with QGY can reduce its CL.Therefore,LVFX combined with QGY in clinical treatment may exhibit potential interactions,and people should pay attention to their medication and dosage.