Metabolic mapping of Schisandra sphenanthera extract and its active lignans using a metabolomic approach based on ultra high performance liquid chromatography with high-resolution mass spectrometry

Schisandra sphenanthera, the dried ripe fruit of Schisandra sphenanthera Rehd. et Wils, is widely used as a restorative, tonic and nutrition in many countries. Wuzhi tablet, an ethanol extract preparation of Schisandra sphenanthera, is a well-known herbal medicine widely used in China. Our previous studies show that Wuzhi tablet and its active lignans significantly protect liver injury. However, its metabolic profile remains unknown in vivo and in vitro. In this study, ultra high performance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry based metabolomics was employed to decipher the metabolic map of Wuzhi tablet and its active lignans. Serum (2 h) and urine (24 h) samples after a 700 mg/kg single oral dose of Wuzhi tablet, and mice liver microsome samples after incubation with its active lignans were collected and analyzed. The data were further analyzed using metabolomics and metabolite identification software. In total, 33 metabolites in vivo and 34 metabolites in vitro were identified, and six among them were new metabolites. The major metabolic reactions encompassed demethylation, hydroxylation, dehydrogenation, and epoxidation. Taken together, in vitro and in vivo studies revealed the metabolic profile of Wuzhi tablet and its active lignans and demethylation and hydroxylation were their major metabolic pathways.