[Pharmacokinetics of four characteristic components from ethanol extract of Rehmanniae Radix in normal and depression...

This study investigated the pharmacokinetic characteristics of four blood-entering components(catalpol, rehmannioside D, rehmapicroside, and verbascoside) from the ethanol extract of Rehmanniae Radix in normal and chronic unpredictable mild stress(CUMS) depression model rats. Ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry(UPLC-Q-Orbitrap-HRMS) was employed to quantitatively analyze the four components in the plasma of normal and CUMS depression model rats administrated with the ethanol extract of Rehmanniae Radix by gavage. The pharmacokinetic parameters of the four components were calculated and compared to explore the effects of depressive disease status on the main components from the ethanol extract of Rehmanniae Radix. The methodological verification results of four blood-entering components(catalpol, rehmannioside D, rehmapicroside, and verbascoside) from the ethanol extract of Rehmanniae Radix showed that the established analytical method for simultaneous determination of the four components met the requirements for the determination of biological samples. The pharmacokinetic results showed that compared with the normal group, the model group demonstrated significantly increased AUC, C_(max), and MRT, prolonged t_(1/2), and decreased CL for catalpol, rehmannioside D, and verbascoside. For rehmapicroside, only C_(max), T_(max), and MRT_(0-t) increased, and no statistical difference was observed for t_(1/2), MRT_(0-∞), AUC, and CL. This study shows that CUMS depression can significantly affect the pharmacokinetic characteristics of catalpol, rehmannioside D, and verbascoside from the ethanol extract of Rehmanniae Radix but exerts limited effect on rehmapicroside, suggesting that the body may have adaptive changes in the absorption, distribution, metabolism, and excretion of drugs under disease conditions.