Rationale: Timosaponin B-II (TB-II) is one of the major bioactive steroid glycosides isolated from Anemarrhena asphodeloides Bge. (Fam. Liliaceae). It has been regarded as a potential lead compound, which may be further developed into a promising new drug for preventing dementia. To fully understand the action mechanism of TB-II, it is important to study the metabolism profile of this compound in vivo.
Methods: Herein, a rapid and sensitive method based on ultrahigh-performance liquid chromatography (UHPLC)/quadrupole-time-of-flight mass spectrometry (QTOFMS) was established to comprehensively investigate the metabolism of TB-II in Sprague-Dawley rat urine following oral administration of a single dose of TB-II at 500.4 mg·kg(-1).
Results: A total of twelve metabolites were detected and identified by means of comparing molecular mass, retention time and spectral pattern of the analytes with those of the parent drug. A possible metabolic pathway on the biotransformation of TB-II was also investigated and proposed.
Conclusions: Oxidation, deglycosylation and E-ring cleavage were found to be the major metabolic processes of the compound in rat. It is the first report on a mammalian metabolism study of timosaponin, a common member of steroid glycosides, in rat urine.
Copyright © 2012 John Wiley & Sons, Ltd.