title: Metabolites characterization of chamaechromone in vivo and in vitro by using ultra-performance liquid chromatography/Xevo G2 quadrupole time-of-flight tandem mass spectrometry.
abstract: BACKGROUND
  Stellera chamaejasme L. (Thymelaeaceae) was a toxic perennial herb and widely used as pesticide and dermatological agents in China. Chamaechromone was a major component in the dried roots of Stellera chamaejasme with anti-HBV and insecticidal activity. Analysis of metabolic profile in vivo and in vitro plays a pivotal role to unravel how TCM works. And the metabolites of chamaechromone might influence the effects and toxicity of Stellera chamaejasme. Moreover, the metabolic routes of chamaechromone provide an important basis for toxicological safety evaluation. Until now, little is known about the metabolism of chamaechromone. The current study was designed to characterize the whole metabolic pathways of chamaechromone in vitro and in vivo.
  
  
  METHODS
  Twenty-four rats were randomly divided into four groups, including two oral administration groups (100mgkg(-1)), one intravenous injection group (5 mgkg(-1)), and one control group. The metabolites in rat urine and feces and bile were identified by UPLC/Q-TOF MS analysis and β-glucuronidase hydrolysis. Moreover, the possible metabolic mechanism was further confirmed by Phase I and Phase II metabolism and catechol-O-methyltransferase methylation in rat liver S9 fraction and degradation in rat intestinal bacteria.
  
  
  RESULTS
  A total of 24 metabolites from chamaechromone were detected and identified in vivo and in vitro, 20 of which were novel. And the major metabolic processes were hydroxylation, methylation, glucuronation, acetylation, dehydroxylation and degradation.
  
  
  CONCLUSIONS
  The present study revealed the whole metabolic pathways of chamaechromone in rat through both in vitro and in vivo experiments for the first time. And chamaechromone could undergo extensive phase I and phase II metabolism in rat. These findings would provide an important basis for the further study and clinical application of chamaechromone. In addition, the results of this work have showed the feasibility of the UPLC/Q-TOF-MS approach for rapid and reliable characterization of metabolites.
authors.affiliation: Laboratory of Pharmaceutical Analysis and Drug Metabolism, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University; The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 QingChun Road, Hangzhou, Zhejiang 310000, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lou
authors.affiliation: Zhejiang Institute for Food and Drug Control, Hangzhou 310004, People's Republic of China.
authors.forename: Jinqi
authors.initials: J
authors.lastname: Zheng
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 QingChun Road, Hangzhou, Zhejiang 310000, People's Republic of China.
authors.forename: Baohong
authors.initials: B
authors.lastname: Wang
authors.affiliation: The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 QingChun Road, Hangzhou, Zhejiang 310000, People's Republic of China.
authors.forename: Xingguo
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Laboratory of Pharmaceutical Analysis and Drug Metabolism, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Laboratory of Pharmaceutical Analysis and Drug Metabolism, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University. Electronic address: zengsu@zju.edu.cn.
authors.forename: Su
authors.initials: S
authors.lastname: Zeng
mesh_terms: D000818:Animals; D001419:Bacteria / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D005243:Feces / Q000737:chemistry; D047309:Flavones / Q000737:chemistry* / Q000378:metabolism*; D007422:Intestines / Q000382:microbiology; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008297:Male; D015394:Molecular Structure; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D053719:Tandem Mass Spectrometry / Q000379:methods*; D029645:Thymelaeaceae / Q000737:chemistry*
chemical_list: D047309:Flavones; C561087:chamaechromone
keywords: Chamaechromone; HPLC; MeOH; Metabolic route; Metabolite; Q-TOF MS; Stellera chamaejasme L.; TCM; UPLC; UPLC/Xevo G2 Q-TOF MS; high-performance liquid chromatography; methanol; quadrupole time-of-flight mass spectrometer; traditional Chinese medicine; ultra-performance liquid chromatography