title: Western blotting analysis for quantitative detection of CYP2C19 expression in liver tissues in the setting of living donor liver transplantation.
abstract: BACKGROUND
  The cytochrome P450 (CYP) drug-metabolizing enzymes play an important role in cellular metabolism. Therapeutic failure or drug toxicity in the period after liver transplantation (LT) is influenced by the drug metabolizing capacity of the graft. The expression levels of CYP2C19 enzyme are often used as an indicator of the functioning of the CYP system. The aim of the present study was to assess the CYP2C19 protein expression in the setting of living donor liver transplantation (LDLT) by using western blotting analysis.
  
  
  METHODS
  We performed CYP2C19 genotyping of liver biopsy samples obtained from 24 donors and 8 recipients each in the pre- and post-LT periods, after which we analyzed the CYP enzyme activity by using western blotting analysis.
  
  
  RESULTS
  The CYP2C19/β-actin ratio, which was an indicator of CYP expression, was 61.75% (23-100%) in donors, 59.13% (15-100%) in pre-LT recipients and 46.71% (12-67%) in post-LT recipients (p>0.05). The CYP2C19 expression levels associated with different genotypes were as follows: homozygous extensive metabolizers (HomEMs; n=24), 56.63±24.74%; heterozygous extensive metabolizers (HetEMs; n=15), 63.0±25.14% and poor metabolizers (PMs; n=1), 82.0% (p>0.05).
  
  
  CONCLUSIONS
  Western blotting analysis showed low CYP2C19 protein expression not only in samples from the pre- and post-LT recipients but also from the donors.
authors.affiliation: Kaohsiung Chang Gung Memorial Hospital, Taiwan, Republic of China.
authors.forename: King-Wah
authors.initials: KW
authors.lastname: Chiu
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Nakano
authors.forename: Hui-Peng
authors.initials: HP
authors.lastname: Tseng
authors.forename: Yu-Fan
authors.initials: YF
authors.lastname: Cheng
authors.forename: Bruno
authors.initials: B
authors.lastname: Jawan
authors.forename: Hock-Liew
authors.initials: HL
authors.lastname: Eng
authors.forename: Shigeru
authors.initials: S
authors.lastname: Goto
authors.forename: Chao-Long
authors.initials: CL
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001706:Biopsy; D015153:Blotting, Western; D002648:Child; D002681:China; D065731:Cytochrome P-450 CYP2C19; D005260:Female; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008099:Liver / Q000201:enzymology* / Q000601:surgery*; D016031:Liver Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015415:Biomarkers; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19