Comparative study on brain pharmacokinetics of Buyang Huanwu Decoction in normal and cerebral ischemia rats using brain microdialysis combined with LC-MS/MS

Objective To conduct a comparative study on the brain pharmacokinetics of seven ingredients(i.e.senkyunolide A,ferulic acid,formononetin,calycosin,ononin,calycosin-O-β-D-glucopyranoside,and paeoniflorin),which were the compounds of Buyang Huanwu Decoction(BHD),in normal and cerebral ischemia rats administrated intragastrically with BHD.Methods The samples of normal and permanent middle cerebral artery occlusion(pMCAO)rats were collected by using brain microdialysis technique.The concentrations of seven ingredients were determined by the HPLC-MS/MS method.After the BHD were administrated intragastrically to the rats for seven consecutive days,brain microdialysis probes were inserted into the hippocampus of rats,and then the brain microdialysates were collected at 20 min time intervals for 5 h.The separation of the seven ingredients and internal standard(IS)was carried out on an ACQUITY UPLC BEH C18(2.1 mm×100 mm,1.7μm)chromatographic column,using a mobile phase consisting of acetonitrile(containing 0.1%formic acid)and water(containing 0.1%formic acid)for gradient elution within 13 min.The ionization was conducted using an ESI source in positive ion mode.Multiple reaction monitoring mode was used for quantification of ingredients in BHD.Results Linearity,accuracy,precision,matrix effect and stability of LC-MS/MS method were all satisfactory,successfully applied to compare the pharmacokinetics of the analytes between normal and model rats after intragastric administration of BHD.Compared with the normal group,the model group after the administration of the BHD showed that T1/2 of formononetin and ononin were longer,and except for calycosin-O-β-D-glucopyranoside(P<0.01),there was no significant difference between the normal group and the model group.The C_(max) of senkyunolide A and calycosin of model group were increased,while the T_(max) of senkyunolide A was decreased,and except for the T_(max) of PF,the differences between the two groups were statistically significant(P<0.01).Conclusion The LC-MS/MS method combined with microdialysis was successfully applied to the comparative study of brain pharmacokinetics of seven ingredients in BHD.After intragastric administration of BHD,there were differences in the pharmacokinetics of seven ingredients in the brain hippocampus between normal rats and model rats,probably related to the characteristics of the ingredients and the effects of cerebral ischemia on the absorption and distribution of the ingredients.

Comparative brain pharmacokinetic study of Jiaotai Pills in normal and insomnic rats using brain microdialysis combinated with LC–MS/MS

Objective：To compare the brain pharmacokinetics of five protoberberine-type alkaloids（i.e.berberine,palmatine,coptisine,epiberberine,and jatrorrhizine）,which were the main bioactive constituents of Jiaotai Pills（JTP）,in normal and insomnic rats orally administrated with JTP.Methods：The detection was conducted by a fully validated liquid chromatography-tandem mass spectrometry combinated with brain microdialysis method.Brain microdialysis probes were inserted into the hippocampus of rats.JTP extracts were administrated intragastrically and then brain microdialysates were collected at 30 min time intervals for 10 h.The separation of the five protoberberine-type alkaloids was carried out on a BDS Hypersilusing a mobile phase consisting of acetonitrile and water（containing 5 mmol ammonium acetate adjusted to p H 5.0）within 4 min.The quantification was performed by multiple reaction monitoring with the transitions of m/z 336.0-320.1 for berberine,m/z 352.0-336.1for palmatine,m/z 338.0-322.1 for jatrorrhizine,m/z 336.0-320.1 for epiberberine,m/z 320.0-292.1 for coptisine and m/z 356.4-192.1 for IS.Results：The lower limit of quantification for five protoberberine-type alkaloids was 0.05 ng/m L.Linearity,accuracy,precision,stability and matrix effect of five analytes were all satisfactory.Five protoberberinetype alkaloids were quickly distributed in the brain.Moreover,significant differences in the principal pharmacokinetic parameters such as AUC andthe analytes were observed between two groups.Conclusion：The LC-MS/MS method combinated with microdialysis is useful in the brain pharmacokinetic study of five protoberberine-type alkaloids.The results indicated that the rates of analytes absorption in insomnic rats were significantly higher than those in normal rats.Besides,the protoberberine-type alkaloids could bring a direct effect on the neuron in the hippocampus.