Intestinal absorption characteristics of root tuber of Cynanchum auriculatum extract in normal and functional dyspepsia model rats via everted intestine sac model

Abstract

The study investigated the difference of intestinal absorption characteristics of root tuber of Cynanchum auriculatum extract between normal and functional dyspepsia(FD) model rats with everted intestine sac model.The content of syringic acid, scopoletin, caudatin, baishouwu benzophenone, qingyangshengenin and deacyhmetaplexigenin in the C.auriculatum extract in different intestinal segments was detected by UPLC-MS/MS.The cumulative absorption amount(Q) and absorption rate constant(K_a) of the six chemical constituents were calculated.The results showed that the six components could be absorbed into the intestinal sac and were unsaturated, which indicated that the absorption mechanism of scopoletin was active transport in the intestine, while that of the other five components were passive diffusion.For normal group, the syringic acid and baishouwu benzophenone in ileum, qingyangshengenin and deacyhmetaplexigenin in ileum and duodenum, and caudatin in colon were well absorbed and scopoletin at low, medium and high concentrations was found excellent absorption in jejunum, ileum, and colon, respectively.Whereas the best absorption site of each component was ileum in model group.The absorption characteristics of each component between normal group and model group were complex at different concentrations, showing inconsistent tendency of absorption, which suggested that the components of root tuber of C.auriculatum extract were selectively absorbed in small intestine, and the absorption characteristics of the six components could be changed under FD status.This study provided theoretical basis for the clinical drug application and development of root tuber of C.auriculatum.