title: Metabolism profile of timosaponin B-II in urine after oral administration to rats by ultrahigh-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry.
abstract: BACKGROUND
  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.
authors: School of Pharmacy, Second Military Medical University, Shanghai 200433, China.
authors: Zhirui
authors: Z
authors: Liu
authors: Dongliang
authors: D
authors: Zhu
authors: Lei
authors: L
authors: Lv
authors: Yueyue
authors: Y
authors: Li
authors: Xing
authors: X
authors: Dong
authors: Zhenyu
authors: Z
authors: Zhu
authors: Yifeng
authors: Y
authors: Chai
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D053858:Metabolic Networks and Pathways; D051381:Rats; D017207:Rats, Sprague-Dawley; D012503:Saponins / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics* / Q000652:urine*; D012680:Sensitivity and Specificity; D013256:Steroids / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics* / Q000652:urine*
chemical_list: D012503:Saponins; D013256:Steroids; C523027:timosaponin B-II