[Effect of PEG400 on pharmacokinetics of baicalin and baicalein in gut microbiotadysbiosis rats].

The study aimed to establish an UPLC-MS/MS method for the determination of baicalin in rat plasma,in order to study the effect of PEG400 on pharmacokinetics of baicalin and baicalein in normal and gut microbiotadysbiosis rats. Plasma was precipitated with ethyl acetate and determined by UPLC-MS/MS method,with genistein as an internal standard. In terms of specificity,linearity,range,accuracy,precision and stability,the method was suitable for the determination of baicalin in plasma. The gut microbiotadysbiosis rat model was induced through the oral administration with lincomycin hydrochloride(5 g·kg-1·d-1) for one week. Samples of plasma of rats were obtained at different time points,after the rats were administrated with baicalin,baicalin and PEG400. Baicalin in rats were detected by UPLC-MS/MS method,and pharmacokinetic parameters were calculated by DAS 3. 2. 2 software. The results showed that the β-glucosidase activity and the number of colonies in the feces of gut microbiotadysbiosis rats induced by lincomycin hydrochloride were significantly reduced. The Cmaxand AUC0-tof the baicalinand PEG400 group in the intestinal flora were significantly lower than those in the normal rat baicalin and PEG400 group. There was no significant difference in Cmaxand AUC0-tbetween the baicalin group and the baicalin+PEG400 group of gut microbiotadysbiosis rats. The Cmaxand AUC0-tof the normal rats baicalin group were significantly higher than those of the gut microbiotadysbiosis rats baicalin group and the baicalin + PEG400 group. There was no significant difference in Cmaxand AUC0-tbetween the normal rat baicalein and PEG400 group and the baicalein group. The Cmaxand AUC0-tof the baicalein group in the gut microbiotadysbiosis rats were lower than those in the normal baicalein group,but significantly higher than those in the baicalein and PEG400 group. PEG400 could increase the absorption of baicalin in normal rats,but is ineffective in gut microbiotadysbiosis rats,with no impact on the absorption of baicalein in rats.