Chemical components characterization and in vivo metabolites profiling of Lingbao Huxin Dan by gas chromatography-mass spectrometry and ultra-high-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry.

Lingbao Huxin Dan (LBHX) is an effective prescription for treating various cardiovascular diseases. However, its systematic chemical composition analysis and important marker components remain unclear, which hinders the development of standards or guidelines for quality evaluation. Herein, a high-resolution and efficient method was established to comprehensively investigate the chemical ingredients and metabolites of LBHX by using gas chromatography-tandem mass spectrometry and ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. AutoDock Vina was applied to conduct visual screening for identifying potential active compounds targeting two important sick sinus syndrome-associated proteins. As a result, 53 volatile compounds, as well as 191 non-volatile chemical components, including bufadienolides, diterpenoids, bile acids, phenolic acids, and triterpenoid saponins, were unambiguously characterized or tentatively identified. Fifty prototypes and 62 metabolites were identified in the plasma of rats, whilst metabolism reactions included phase I reactions (hydrolysis, oxidation, and hydroxylation) and phase II reactions (glucuronidation and methylation). Eleven compounds with good binding affinity have been observed by docking with key proteins. It is the first systematic study on the pharmacodynamic material basis of LBHX and the result consolidates the foundation for further study regarding the mechanism in treating cardiovascular diseases.