Identification of the Absorbed Constituents and Metabolites of Shenyanshu Tablets in Rat Plasma by Ultrahigh-Performance Liquid Chromatography Coupled With Quadrupole Time-of-Flight Mass Spectrometry.

Shenyanshu Tablets (SYST) is a traditional Chinese patent medicine composed of 10 kinds of Chinese herbal medicines, which has the functions of tonifying the kidney and strengthening the spleen, promoting diuresis and reducing swelling. It is well known that SYST can be used to treat chronic nephritis. However, due to the complexity of the formula, the pharmacological active components in SYST that can be absorbed into plasma have not been fully studied. In this study, an ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) method was first developed for separating and identifying the absorbed components and metabolites of SYST in rat plasma. A total of 33 compounds were identified or preliminarily characterized, including 18 prototype components and 15 metabolites. The results demonstrated that alkaloids, fatty acids, organic acids, and triterpenoid glycosides were the main prototype components, and triterpenoid glycoside-related metabolites, fatty acid-related metabolites, and flavonoid-related metabolites were the major metabolites. These findings clarify the material basis of SYST in the treatment of chronic nephritis and provide references for further research and development of SYST.