LC/MS/MS method for analysis of E2 series prostaglandins and isoprostanes

A quantitiative LC-MS/MS method for the measurement of arachidonic acid, prostanoids, endocannabinoids, N-acylethanolamines and steroids in human plasma

“…Consequently, we selected ACN precipitation, followed by SPE clean up, could not be analyzed in this mode [24,[36][37][38]. Only one publication measured AA in positive mode (using a Micromass Quatro Micro spectrometer from Waters) [39], but these results could not be reproduced using our instrument.…”

Targeted lipidomic strategies for oxygenated metabolites of polyunsaturated fatty acids

“…Alternative extraction procedures using ether [74], acetone/chloroform [64], hexane–isopropanol [75], and ethyl acetate/ethanol mixtures have been proposed for a wide range of tissues. LLE has proven to be a valid high-throughput alternative to SPE for the extraction of lipid metabolites from biological matrices such as urine samples [53, 76] and brain samples [64, 77]. Additionally, LLE can be used in combination with SPE to maximize the purification of oxygenated PUFA species prior to further MS analysis [66, 78–80].…”

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During the last decade, a growing number of oxygenated PUFA species, including the anti-inflammatory mediators lipoxins, resolvins, protectins and maresins, have been discovered, while their complete biochemical characterization is still underway [95–99]. Furthermore, the existence of very long chain PUFA in humans (C24–C36) [100–103] might suggest the existence of their respective oxygenated metabolites, albeit they have not yet been characterized.

Besides existing in their unbound or free form, oxygenated PUFA moieties are found esterified to complex lipids (e.g., glycerophospholipids, glycerolipids and cholesteryl esters) [34, 70, 77, 104–116] or amide-conjugated to ethanolamine (e.g., prostamides) [115, 117] and various amino acids [10, 118], whose mechanism of formation and action has not yet been fully elucidated.Unusual eicosanoids and related molecules derived from gut microbiome metabolism [119, 120] and dietary sources such as plants (e.g., jasmonic acid) [118], animal meat, and dairy (conjugated-linoleic acid) [121], further contribute to the overall complexity of oxygenated PUFA species found in human tissues and biological fluids, possibly mediating yet-to-be explored biological activities. …”

Application of lipid peroxidation products as biomarkers for flutamide-induced oxidative stress in vitro

“…Especially isomers from the F-ring (dihydroxypentan) class have been investigated extensively. However, recent studies also showed that isomers from the Dand E-ring group (hydroxypentanon) can serve as biomarkers and bioactive substances (Cossette et al, 2007;Brose et al, 2011).…”