title: Characterization of cardamonin metabolism by P450 in different species via HPLC-ESI-ion trap and UPLC-ESI-quadrupole mass spectrometry.
abstract: OBJECTIVE
  To characterize the metabolism of cardamonin by the P450 enzymes in human and animal liver microsomes.
  
  
  METHODS
  Cardamonin was incubated with both human and animal liver microsomal incubation systems containing P450 reaction factors. High performance liquid chromatography coupled with ion trap mass spectrometry was used to identify the metabolites. Serial cardamonin dilutions were used to perform a kinetic study in human liver microsomes. Selective inhibitors of 7 of the major P450 isozymes were used to inhibit cardamonin hydroxylation to identify the isozymes involved in cardamonin metabolism. The cardamonin hydroxylation metabolic capacities of human and various other animals were investigated using the liver microsomal incubation system.
  
  
  RESULTS
  Two metabolites generated by the liver microsome system were detected and identified as hydroxylated cardamonin. The Km and Vmax values for cardamonin hydroxylation were calculated as 32 micromol/L and 35 pmol x min(-1) x mg(-1), respectively. Furafylline and clomethiazole significantly inhibited cardamonin hydroxylation. Guinea pigs showed the highest similarity to humans with respect to the metabolism of cardamonin.
  
  
  CONCLUSIONS
  CYP 1A2 and 2E1 were identified as the P450 isozymes involved in the metabolism of cardamonin in human liver microsomes. Furthermore, our research suggests that guinea pigs could be used in the advanced pharmacokinetic studies of cardamonin in vivo.
authors.affiliation: The MOE Key Laboratory for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201210, China.
authors.forename: Yu-Qi
authors.initials: YQ
authors.lastname: He
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Jiang-Wei
authors.initials: JW
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Tang
authors.forename: Juan
authors.initials: J
authors.lastname: Su
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Li
authors.forename: Yan-Liu
authors.initials: YL
authors.lastname: Lu
authors.forename: Chang-Hong
authors.initials: CH
authors.lastname: Wang
authors.forename: Ling
authors.initials: L
authors.lastname: Yang
authors.forename: Zheng-Tao
authors.initials: ZT
authors.lastname: Wang
mesh_terms: D000328:Adult; D000818:Animals; D044466:Asian People / Q000235:genetics; D001344:Autopsy; D002417:Cattle; D047188:Chalcones / Q000302:isolation & purification / Q000378:metabolism*; D002681:China; D002719:Chlormethiazole / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D006801:Humans; D006900:Hydroxylation / Q000187:drug effects; D007477:Ions / Q000737:chemistry; D007700:Kinetics; D008297:Male; D051379:Mice; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D051381:Rats; D012756:Sheep; D013045:Species Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013552:Swine; D013806:Theophylline / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D047188:Chalcones; D004791:Enzyme Inhibitors; D007477:Ions; D002719:Chlormethiazole; D003577:Cytochrome P-450 Enzyme System; D013806:Theophylline; C050131:furafylline; C436747:cardamonin