Deciphering the chemical constituents of Shengjiang Xiexin decoction by ultrahigh‐performance liquid chromatography‐quadrupole/orbitrap high‐resolution mass spectrometry and the impact of 20 characteristic components on multidrug resistance‐associated protein 2 in the vesicular transport assay

Shengjiang Xiexin decoction, a traditional Chinese medical formula, has been utilized to alleviate the delayed‐onset diarrhea induced by irino tecan. However, the chemical constituents of this formula and the activities of its constituents remain unclear. In this study, ultrahigh‐performance liquid chromatography‐quadrupole/orbitrap high‐resolution mass spectrometry was employed to comprehensively analyze the chemical constituents of Shengjiang Xiexin decoction. A total of 270 components, including flavonoids, coumarins, triterpenoids, alkaloids, diarylheptanoids and others, were identified or characterized. Multidrug resistance‐associated protein 2 is an efflux transporter responsible for regulating drug absorption. A total of 20 characteristic components from the formula were selected to evaluate their effects on the function of multidrug resistance‐associated protein 2 using the vesicular transport assay. Glycyrrhizic acid and glycyrrhetinic acid were identified as potential multidrug resistance‐associated protein 2 inhibitors, while 9 flavonoid aglycones increased the uptake of the substrate [ 3 H]‐estradiol 17‐ β ‐glucuronide in the vesicles. This was the first systematic investigation of the chemical constituents from Shengjiang Xiexin decoction and the effect of its characteristic components on the transporter. The results offered a basis for further exploring the detoxification mechanisms of this formula and its interactions with other drugs.