Dihomo-isoprostanes—nonenzymatic metabolites of AdA—are higher in epileptic patients compared to healthy individuals by a new ultrahigh pressure liquid chromatography–triple quadrupole–tandem mass spectrometry method

• Published in: Free radical biology & medicine 2015-02, Vol.79, p.154-163
• Main Authors: Medina, Sonia, Miguel-Elízaga, Irene De, Oger, Camille, Galano, Jean-Marie, Durand, Thierry, Martínez-Villanueva, Miriam, Castillo, María Luisa Gil-Del, Villegas-Martínez, Irene, Ferreres, Federico, Martínez-Hernández, Pedro, Gil-Izquierdo, Ángel
• Format: Article
• Language: English
• Subjects: Adult; Biomarkers; Biomarkers - urine; Calibration; Case-Control Studies; Chemical Sciences; Chromatography, High Pressure Liquid; Chromatography, High Pressure Liquid - methods; Dihomo-isoprostanes; Epilepsy; Epilepsy - urine; Female; Free radicals; Humans; Hydrolysis; Isoprostanes; Isoprostanes - urine; Male; Methods; Neuroprostanes; Oxidative stress; Tandem Mass Spectrometry; Tandem Mass Spectrometry - methods; UHPLC–QqQ–MS/MS; Urine
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2014.11.005

Oxidative stress is a biochemical state in which reactive oxygen species are generated and it has been associated with pathological states including epilepsy. Therein, neuroprostanes (NeuroPs) and dihomo-isoprostanes (Dihomo-IsoPs)—a series of compounds formed nonenzymatically through free radical-induced DHA, n-6 DPA, and AdA peroxidation–are implicated in the pathophysiological status of various human neurological diseases. A new, robust, and selective analytical method for the determination of 10 NeuroPs/Dihomo-IsoPs in human urine, using solid-phase extraction and UHPLC–QqQ–MS/MS in the multiple reaction monitoring mode (using a negative electrospray ionization interface), was developed. Nine NeuroPs/Dihomo-IsoPs were identified in 15 epileptic patients, matched with healthy volunteers. Among them, 17-F2t-Dihomo-IsoP, Ent-7(R)-7-F2t-Dihomo-IsoP, and Ent-7-epi-7-F2t-Dihomo-IsoP, derived from adrenic acid (AdA), were significantly higher in epileptic patients than in healthy volunteers. The validated method provided a high-throughput assay with a limit of detection and limit of quantification for each analyte of 0.10–5.90ngmL−1 and 0.15–11.81ngmL−1, respectively. The intra- and interday variations were lower than 14%. Dihomo-IsoPs have been considered as potential markers of epilepsy for the first time and their measurement may increase the understanding of the role of oxidative stress in neurological diseases, in intra vitam studies. The present study highlights a potential role of Dihomo-IsoPs as biomarkers in persons with epilepsy, though its mechanisms and possible implications should be the subject of further investigations. [Display omitted] •New validated method for the detection of NeuroPs/Dihomo-IsoPs by UHPLC–QqQ–MS/MS.•Determination of 10 NeuroPs/Dihomo-IsoPs in human urine.•Dihomo-IsoPs were higher in epileptic patients than healthy volunteers.