Pharmacokinetics, tissue distribution and excretion of six bioactive components from total glucosides picrorhizae...

Total glucosides picrorhizae rhizome (TGPR) is an innovative traditional Chinese medicine, which is a candidate drug for the treatment of nonalcoholic steatohepatitis (NASH). However, there is still lack of deep research on the behaviors of TGPR in vivo. In this study, a reliable, specific, and sensitive liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been constructed for simultaneous determination of picroside I, picroside II, vanillic acid, androsin, cinnamic acid and picroside IV, the major active constituents of TGPR, in rat various biological matrices (plasma, tissue, bile, urine and feces) using diphenhydramine hydrochloride and paeoniflorin as the internal standard. All biosamples were prepared using a simple protein precipitation with acetonitrile. Chromatographic separation was achieved on a waters UHPLC® HSS T3 (100×2.1 mm, 1.8 μm) column. The mobile phase consisted of methanol: acetonitrile1(1:1, V/V) and 0.5 mM ammonium formate in water, was employed to separate six components from endogenous interferences. The components were detected with a triple quadrupole mass spectrometer using positive and negative ion multiple reaction monitoring (MRM) mode. The newly developed method was successfully applied to investigate the pharmacokinetics, tissue distribution and excretion of six components in rats. The pharmacokinetic results indicated that the six components in TGPR could be quickly absorbed and slowly eliminated and their bioavailability were less than 12.37%, which implied the poor absorption after intragastric dosing. For tissue distribution, the six components in TGPR were detected in liver and only androsin could penetrate the blood-brain barrier. Meanwhile, the excretion study demonstrated that vanillic acid was mostly excreted as prototype drugs and the remaining five components might be widely metabolized in vivo as the metabolites, the unconverted form was excreted mainly by feces route. The pharmacokinetics, tissue distribution and excretion characteristics of six bioactive components in TGPR were firstly revealed, which will provide references for further clinical application of TGPR as an anti-NASH drug.