Optimized ultra-high-performance liquid chromatography tandem mass spectrometry method for detecting compositional changes in Eucommia ulmoides and Achyranthes bidentata paired decoctions in vitro and in vivo

Abstract

The bark of Eucommia ulmoides and the roots of Achyranthes bidentata are commonly used in traditional Chinese medicine, and their pairing appears in many traditional Chinese medicine formulas as a recognized compatible unit. However, the changes and interactions of the main components of these two formulas when paired remain unclear, and there is currently no standard or method for their quality control and assessment of pharmacological effects.An optimized ultra-high-performance liquid chromatography triple-quadrupole mass spectrometry (UHPLC-MS/MS) method was established for the simultaneous identification of 10 components in E. ulmoides and A. bidentata using in vitro and in vivo models. Tributyltin methacrylate was the internal standard solution, and the blood samples were treated by an organic solvent precipitation method. Gradient elution was conducted on a C18 column at 25 °C with 0.1% formic acid water:acetonitrile as the mobile phase at a flow rate of 0.5 mL min−1. Dynamic multiple response monitoring was performed in negative-ion mode using an Agilent Jet Stream electrospray ionization ion source.In negative-ion detection mode, eucommiol exhibited a good response, and the isomers ginsenoside Ro and achyranthoside C could also be well separated. The developed method accurately detected the five components with a low blood content. Compared to controls, the levels of ginsenoside Ro, chikusetsusaponin Ⅳa, and achyranthoside C increased; the contents of geniposidic acid and pinoresinol diglucoside were unchanged; and the levels of eucommiol, geniposide, β-ecdysterone, genipin, and achyranthoside D decreased in vitro. In vivo, the contents of geniposidic acid, geniposide, pinoresinol diglucoside, and β-ecdysterone were reduced; the contents of eucommiol and ginsenoside Ro were unchanged; and those of achyranthoside D, chikusetsusaponin Ⅳa, and achyranthoside C increased compared to the corresponding levels in the internal control.A method for the quality control of the E. ulmoides-A. bidentata drug pair was established for the first time and the main components in 10 drug pairs could be determined simultaneously in vitro and in vivo. These findings show that the E. ulmoides and A. bidentata drug pair cause a compositional change, providing new ideas for the development of this combination to improve clinical efficacy.