Isoflavones Influence On Pharmacokinetic Profiles Of Main Iridoids From Gardeniae Fructus In Rat

Gardeniae Fructus(GF),commonly called Zhizi in Chinese,is the dried and ripe fruit of Gardenia jasminoides Ellis.In particular,iridoids have been regarded as the main active ingredients in GF.In Chinese,GF is one herb which is widely used to make the traditional Chinese formula with Semen Sojae Praeparatum(SSP).SSP may be influence on the metabolism of iridoids.The major active constituents of SSP are known as isoflavones.Isoflavones are natural phenolic compounds in traditional Chinese medicine(TCM)and have an effect on the prevention of most chronic diseases.In our previous study,we found isoflavones in diet could influence the pharmacokinetics of the glycosides which metabolized by?-glucosidase via gut micrbiota.Iridoids is a kind of glycosides and metabolized by?-glucosidase.Therefore,this study focus on the effect of isoflavones on the pharmacokinetics of iridoids from GF.Firstly,we established a method to determine shanzhiside,genipin1-gentiobioside and geniposide from GF by LC-MS/MS.Then,an LC-MS/MS method for simultaneous determination of shanshiside,genipin 1-gentiobioside,geniposide and genipin was developed.In addition,we compared the pharmacokinetics of four iridoids in normal rats with those in rats exposed to isolfavones for different consecutive days.1.A sensitive LC-MS/MS method for simultaneous quantification of three iridiods in GFA simple,rapid and sensitive method for the determination of major compounds from GF was developed using LC-MS/MS.This validated method has good selectivity,sensitivity and accuracy.The analysis was performed on an Dikma Diamonsil~?C18(100×4.6 mm,5?m)column with acetonitrile(0.1%acetic acid)and(0.1%acetic acid)water as mobile phase at a rate of 0.4 ml/min for 5 mins.Quantification of these compounds were performed by LC-MS/MS with positive(genipin 1-gentiobioside)or negetive(shanzhiside and geniposide)ion mode ESI in the MRM mode.This excellent linearity,accuracy,recovery,repeatability and stability had infered that the method is able to apply to pharmacokinetic study.2.The development and validation of analytical method for three iridoids and a metabolite in rats plasmaWe developed a rapid,reliable and sensitive LC-MS/MS method for the determination of three iridoids and a metabolite in normal rats and isoflavones exposed rats.The excellent sensitivity,selectivity,accuracy,precision and stability proved this method is able to apply to the pharmacokinetic study of three iridoids and a metabolite.Solid-phase extraction(SPE)was performed to extract the analytes from rats plasma and paeoniflorin was regarded as the IS.A waters Atlantis T3(3?m,4.6×150 mm)column with a flow rate of 0.6 mL/min for 19mins was used for the chromatographic separation.The ionization and detection of the analytes and IS were carried out on a triple quadrupole mass spectrometer.Quantitation was performed by positive(for genipin 1-gentiobioside)and negative(for shanzhiside,geniposide,genipin and IS)MRM mode.All calibration curves proved good linearity(r>0.99)over a wide concentration range for all analytes.The intra-and inter-day precision values(RSD%)were less than 12.2% and the accuracy values ranged from-10.1 to16.4% for intra-day and from-2.5 to 7.8% for inter-day,which demonstrated that the method was precise and accurate.The extraction recovery of the analytes ranged from53.8 to 99.7%,and the matrix effects ranged from 81.2 to 89.2%with a little ion supression,which suggested that the values were all in the acceptable ranges.This method could be true to the pharmacokinetic study of iridoids in GF.3.The pharmacokinetic study on the three iridoids and a metabolite after oral administration of GF extract in SD ratsThe developed method was used to measure the plasma concentration of shanzhiside,genipin 1-gentiobioside,genposide and genipin after oral administration of GF extract in normal rats.We plotted the drug concerntration time curve for four analytes and caculated the pharmacokinetic parameters.The results could be the reference on the pharmacokinetic study of iridoids after oral administration of GF extract in rat plasma.4.The pharmacokinetic study on the three iridoids and a metabolite after oral administration of GF extract in rats exposed to isoflavonesWe divided SD rats into four groups and oral administration of isoflavones for 7days,14 days,21 days and 28 days,respectively.The developed method was used to measure the plasma concentration of shanzhiside,genipin 1-gentiobioside,genposide and genipin after oral administration of GF extract in rats exposed to isoflavones for different time.We plotted the drug concerntration time curve for four analytes and caculated the pharmacokinetic parameters.The results could be the reference on the pharmacokinetic study of iridoids after oral administration of GF extract in rat exposed to isoflavones.5.Isoflavones influence on pharmacokinetic profiles of main iridoids from GF in ratThere were difference in pharmacokinetics between normal rats and isoflavones exposed rats after oral administration of GF extract.With the increase of isoflavones exposure time,the change of pharmacokinetic parameters of four analytes and the constent of genipin sulfate showed a consistent trend.It was suggested that the gut microbiota and metabolic enzymes may alter with the increase of isoflavones.So,it is necessary to pay attention to the interaction with the drugs and the effect of drug on the metabolism by gut mcrobiota.