Effects of processing on the efficacy and metabolites of Cistanche tubulosa using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

Cistanche tubulosa (CT), a well-known traditional Chinese medicine, has always been processed with rice wine for the treatment of kidney-yang deficiency syndrome (KYDS) since time immemorial. To explore the effect of processing on the efficacy and metabolites of CT in vivo, a comprehensive method using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was established for the analysis of the altered endogenous metabolites in response to the intervention of the raw and processed CT in KYDS model and the metabolites of the absorbed compounds in rats after gastric perfusion. It was shown that CT could improve KYDS, and the effect of the processed product was more significant. A total of 47 differential metabolites were identified in urine. Pathway analysis proved that purine metabolism; alanine, aspartate, and glutamate metabolism; and citrate cycle were the main pathways. Furthermore, 53 prototypes and 48 metabolites have been detected in rats. This was the first systematic research focus on the metabolites of raw and processed CT in vivo, which could provide a scientific basis for explaining the increasing efficiency of the processed CT. Moreover, it provides a valuable strategy for analyzing the chemical components and metabolites of other TCM prescriptions.