Bile metabolites identification and excretion study in normal and acute ALI rats after intragastric administration of Penthorum chinense extract by UHPLC/MS

Penthorum chinense has multiples of pharmacological activities such as hepatoprotective, antibacterial, antioxidant, anti-inflammatory and hypoglycemic activities. To date, there have been no relevant reports on the metabolism of P. chinense in vivo so far. This study aims to analyze P. chinense metabolism and excretion in rat bile of normal and acute alcoholic liver injury (ALI). Six Sprague-Dawley male rats were divided into normal and acute ALI groups ( n = 3 for each group). The bile samples were collected after intragastric administration of P. chinense extract at a dose of 2.82 g/kg. The bile metabolites in normal and acute ALI groups were qualitatively characterized and identified by UHPLC/MS. Furthermore, the bile samples of different time periods were quantitatively assay for excretion study. A total of nine prototypes and 177 metabolites were characterized, including flavonoids, organic acids and phenylpropanoids. Moreover, bile excretion amounts of five dihydroflavonoids [alpinetin (ALP), pinocembrin (PCB), naringenin (NRG), pinocembrin-7- O - β - D -glucoside (PCBG), and 5-methoxypinocembroside (5-MPB)] were measured in rats. The excretion process in the acute ALI rats was relatively slow compared with that of normal rats. The excretion rates of ALP, PCB and NRG were higher than those of PCBG and 5-MPB. This present study provides a basis for the pharmacodynamic substance basis and clinical application of this herbal medicine.