title: In vitro evidence of possible influence of scutellarein towards bile acids' metabolism.
abstract: BACKGROUND
  The glucuronidation process has been regarded as the key elimination process for toxic bile acids. UDP-glucuronosyltransferase (UGT) 1A3 is one important metabolizing enzyme involved in this process.
  
  
  OBJECTIVE
  To evaluate the inhibition of UGT1A3 by scutellarein which is an important herbal ingredient using in vitro method, trying to indicate the possibility of toxicity due to the accumulation of toxic bile acids.
  
  
  METHODS
  Due to the difficulty to gain the standards of biles acids' glucuronides, the recombinant UGT1A3-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed to profile the activity of UGT1A3.
  
  
  RESULTS
  The results showed that scutellarein inhibited UGT1A3 in a concentration-dependent behaviour. Competitive inhibition was demonstrated using both Dixon plot and Lineweaver-Burk plot, and the inhibition kinetic parameter (Ki) was calculated to be 5.8uM.
  
  
  CONCLUSIONS
  All these data reminded the necessary monitoring of the levels of bile acids in plasma when utilizing scutellarein and the herbs containing this compound.
authors.affiliation: Department of Pharmacy, Cancer Hospital of Shantou University Medical College, No.7 Raoping Road, Shantou, 515031, Guangdong, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Shu-Yao
authors.forename: J
authors.initials: J
authors.lastname: Hong
authors.forename: L
authors.initials: L
authors.lastname: Chao-Xian
authors.forename: Z
authors.initials: Z
authors.lastname: Zhi-Wei
authors.forename: Xin
authors.initials: X
authors.lastname: Dai-Shan
authors.forename: C
authors.initials: C
authors.lastname: Lei
mesh_terms: D047310:Apigenin / Q000494:pharmacology*; D001647:Bile Acids and Salts / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D014453:Glucuronosyltransferase / Q000037:antagonists & inhibitors*; D006923:Hymecromone; D050356:Lipid Metabolism / Q000187:drug effects
chemical_list: D001647:Bile Acids and Salts; D004791:Enzyme Inhibitors; D006923:Hymecromone; D047310:Apigenin; C122075:UDP-glucuronosyltransferase, UGT1A3; D014453:Glucuronosyltransferase; C458179:scutellarein
keywords: bile acids metabolism; in vitro methods; scutellarein