nitrophenols and phenyl-acetate

Mammalian paraoxonase-1 hydrolyses a very broad spectrum of esters such as certain drugs and xenobiotics. The aim of this study was to determine whether carbamates influence the activity of recombinant PON1 (rePON1). Carbamates were selected having a variety of applications: bambuterol and physostigmine are drugs, carbofuran is used as a pesticide, while Ro 02-0683 is diagnostic reagent. All the selected carbamates reduced the arylesterase activity of rePON1 towards the substrate

Topics: Acetates; Aryldialkylphosphatase; Carbamates; Carbofuran; Carboxylic Ester Hydrolases; Humans; Models, Molecular; Nitrophenols; Phenols; Terbutaline

To evaluate and validate 3 spectrophotometric assays for measuring serum activity of paraoxonase type-1 (PON1), an enzyme associated with high-density lipoproteins, in dogs.. 22 healthy adult dogs and 10 dogs with eccentrocytosis.. 2 methods were adapted for use in 96-well microplates with phenyl acetate and 5-thiobutyl butyrolactonase as substrates, and 1 was adapted for use in an automated analyzer with p-nitrophenyl acetate as substrate. Blood samples were collected from all dogs, serum was harvested, and serum PON1 activity was measured with each method.. Imprecision was low for all 3 methods, with the exception of interassay imprecision for 5-thiobutyl butyrolactonase, and results were linear across serial sample dilutions. The 3 methods were able to detect low PON1 activity when EDTA was used for blood sample collection, yielded lower PON1 values in sick dogs with eccentrocytosis than in healthy dogs, and yielded highly correlated results.. The methods described here may allow a wider use of PON1 activity as a biomarker of oxidative stress in dogs in clinical and research settings. Results of each method were robust and precise (with the exception of the interassay values for the lactonase method), and the methods were easy to set up in a laboratory.

Topics: Acetates; Animals; Aryldialkylphosphatase; Biomarkers; Carboxylic Ester Hydrolases; Dogs; Female; Male; Nitrophenols; Oxidative Stress; Phenols; Spectrophotometry