title: Relationships between paraoxon and 2-coumaranone hydrolytic activities in sera genotyped for PON1 Q192R polymorphism.
abstract: OBJECTIVE
  To set-up a method for a direct evaluation in human serum of paraoxonase enzymatic activities, establishing a possible correlation with Q192R genotype polymorphism.
  
  
  METHODS
  101 different human serum samples were genotyped for paraoxonase Q192R polymorphism by PCR restriction analysis, and evaluated spectrophotometrically with regard to paraoxon and 2-coumaranone hydrolytic activities. Both activities of paraoxonase were assayed, quantified through normalization by arylesterase activity, and compared with the data concerning Q/R genetic polymorphism.
  
  
  RESULTS
  The mean normalized paraoxonase activity was found to be significantly higher in RR than in QQ human sera (3.99+/-0.6 versus 1.32+/-0.44; P<0.0001); instead, the 2-coumaranone hydrolysis showed an opposite trend (0.10+/-0.02 versus 0.23+/-0.04, in RR and QQ sera respectively; P<0.0001).
  
  
  CONCLUSIONS
  These methods were successfully applied to the whole serum, suggesting a possible use of this approach for a clinically relevant phenotypic characterization.
authors.affiliation: Department of Biomedical Sciences, University of Teramo, Teramo, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Giacominelli-Stuffler
authors.forename: Clotilde Beatrice
authors.initials: CB
authors.lastname: Angelucci
authors.forename: Laura
authors.initials: L
authors.lastname: Liberatoscioli
authors.forename: Claudio
authors.initials: C
authors.lastname: Cortese
authors.forename: Enrico
authors.initials: E
authors.lastname: Dainese
authors.forename: Mauro
authors.initials: M
authors.lastname: Maccarrone
mesh_terms: D000328:Adult; D043303:Aryldialkylphosphatase / Q000378:metabolism*; D001572:Benzofurans / Q000378:metabolism*; D002800:Cholinesterase Inhibitors / Q000378:metabolism*; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D010261:Paraoxon / Q000378:metabolism*; D011110:Polymorphism, Genetic; D013379:Substrate Specificity
chemical_list: D001572:Benzofurans; D002800:Cholinesterase Inhibitors; C545827:2-coumaranone; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human; D010261:Paraoxon