Identification of prototype compounds and derived metabolites of naoxintong capsule in beagle dog urine and feces by UFLC-Q-TOF-MS/MS

Naoxintong Capsule (NXTC) is a well-known Traditional Chinese Medicine (TCM) medication that has been widely employed in the treatment of cardiovascular and cerebrovascular diseases. Although its chemical constituents had been characterized, the in vivo biotransformation of those components remain obscured. In this study, by applying the ultra-fast liquid chromatography/quadrupole-time-of-flight tandem mass spectrometry (UFLC-Q-TOF-MS/MS), we have investigated the in vivo metabolism of NXTC in beagle dog urine and feces. After a single dose of oral administration, a total of 36 prototype compounds and 52 metabolites of NXTC were identified or tentatively characterized in beagle dog urine and feces. We have also proposed the in vivo transformation pathways of such metabolites including phase I (reduction, oxidation, hydroxylation, demethylation) and phase II reactions (glucuronidation, sulfation, methylation). For the first time, our results have unsealed the in vivo metabolic profiles of chemical components of NXTC in beagle dogs and added novel knowledge into the understanding of efficacy contributing compounds of NXTC that deserves further investigation. (C) 2019 Elsevier B.V. All rights reserved.