title: Quantification of dinor, dihydro metabolites of F2-isoprostanes in urine by liquid chromatography/tandem mass spectrometry.
abstract: The F2-isoprostanes (F2-IsoP) are a series of prostaglandin (PG)-F2-like compounds that are produced by free-radical-mediated oxidation of arachidonic acid. One F2-IsoP with potent biological activity is 15-F2t-IsoP and increased levels of 15-F(2t)-IsoP have been measured in several diseases. The major urinary metabolite of 15-F2t-IsoP (8-iso-PGF(2alpha)) is 2,3-dinor-5,6-dihydro-15-F2t-IsoP (15-F2t-IsoP-M). Previously, we developed a stable isotope dilution gas chromatography/negative chemical ionization/mass spectrometry (MS) assay for 15-F2t-IsoP-M, which, while highly sensitive, required time-consuming derivatization and thin-layer chromatography purification. We now report the development of a more rapid high-performance liquid chromatography method coupled to electrospray ionization-tandem mass spectrometry (LC/MS/MS) to analyze all of the dinor,dihydro metabolites of the F2-IsoP isomers (F2-IsoP-M). The precision of this assay was +/-5.0% and the accuracy 80%. The assay remained linear over a range of 1-100 ng injected onto the LC column. Levels of F2-IsoP-M determined by the LC/MS/MS assay method significantly correlated with levels of 15-F2t-IsoP-M determined by the GC/MS assay (R = 0.77y = 67.2x-0.5). The levels of F2-IsoP-M detected in spot urines from 40 normal subjects were 38.1+/-19.1 ng/mg creatinine (mean+/-SD). This method provides an accurate and rapid assay to assess oxidative status in vivo.
authors.affiliation: Department of Pharmacology, Vanderbilt University, Nashville, TN 27232, USA. sean.davies@vanderbilt.edu
authors.forename: Sean S
authors.initials: SS
authors.lastname: Davies
authors.forename: William
authors.initials: W
authors.lastname: Zackert
authors.forename: Yao
authors.initials: Y
authors.lastname: Luo
authors.forename: Carol C
authors.initials: CC
authors.lastname: Cunningham
authors.forename: Madlyn
authors.initials: M
authors.lastname: Frisard
authors.forename: L Jackson
authors.initials: LJ
authors.lastname: Roberts
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D015237:Dinoprost / Q000031:analogs & derivatives / Q000652:urine; D028441:F2-Isoprostanes / Q000378:metabolism* / Q000652:urine*; D006801:Humans; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: C433484:2,3-dinor-5,6-dihydro-15-F-isoprostane; D028441:F2-Isoprostanes; D015237:Dinoprost