Effect of Panax notoginseng saponins on the pharmacokinetics of aspirin in rats

•In summary, this is the first report to evaluate the drug–drug interaction between aspirin and Panax Notoginseng Saponins about pharmacokinetics in rats.•The pharmacokinetic curve and Cmax of salicylic acid show marked increase when the drugs were taken together.•Cell experiment is also used to study the absorption of aspirin and salicylic acid. The result of cell experiment is consistent with the pharmacokinetic study. Aspirin (ASA) is widely used to treat fever, pain, inflammation and cerebral infarction in clinic. Panax Notoginseng Saponins (PNS) is the extracts of Panax Notoginseng (PN)-a traditional Chinese medicine extensively used in cardiovascular diseases. Panax notoginseng saponins and ASA are both widely used to treat cerebral infarction in China. Good results in clinical practice have been achieved when the two drugs were taken together. To investigate the effect of PNS on ASA in vivo, the concentrations of salicylic acid (SA) in blood were measured after oral administration of ASA or ASA combined with PNS by UPLC–MS/MS. Sample preparation was carried out by the protein precipitation technique with an internal Saikosaponin A standard. The separation of two components was achieved by using an ACQUITY UPLC ®BEH C18 Column (1.7μm 2.1×100mm) by gradient elution using water (containing 0.2% formic acid) and acetonitrile (containing 0.2% formic acid) as the mobile phase at a flow rate of 0.2mL/min. The pharmacokinetic parameters were determined by using non-compartmental analysis. The results suggested that drug–drug interaction in vivo existed between PNS and ASA. The concentration of the SA was increasing when the two drugs were administered together. The transport of ASA and SA in MDCK −MDR1 cell monolayer was used to verify this conclusion. The values of apparent permeability coefficients (Papp) were significantly increased when the two drugs were used together. This result suggested PNS could increase the gastrointestinal tract absorption of ASA and SA. These findings provide more insight for wise use of two drugs to treat or prevent cardiovascular diseases.