Lipidomics of oxidized polyunsaturated fatty acids

Abstract

Lipid mediators are produced from the oxidation of polyunsaturated fatty acids through enzymatic and free radical-mediated reactions. When subject to oxygenation via cyclooxygenases, lipoxygenases, and cytochrome P450 monooxygenases, polyunsaturated fatty acids give rise to an array of metabolites including eicosanoids, docosanoids, and octadecanoids. These potent bioactive lipids are involved in many biochemical and signaling pathways, with inflammation being of particular importance. Moreover, because they are produced by more than one pathway and substrate, and are present in a variety of biological milieus, their analysis is not always possible with conventional assays. Liquid chromatography coupled to electrospray mass spectrometry offers a versatile and sensitive approach for the analysis of bioactive lipids, allowing specific and accurate quantitation of multiple species present in the same sample. Here we explain the principles of this approach to mediator lipidomics and present detailed protocols for the assay of enzymatically produced oxygenated metabolites of polyunsaturated fatty acids that can be tailored to answer biological questions or facilitate assessment of nutritional and pharmacological interventions.

An Advanced LC–MS/MS Platform for the Analysis of Specialized Pro-Resolving Lipid Mediators

“…The cycle time of 14 min is almost half as short as described for other platforms while monitoring an equal number of substances [11]. While nearly all described analysis platforms for SPM are making use of a SPE cleanup step, we here show that simple protein-precipitation with MeOH followed by dilution with water allows the sensitive and robust analysis of SPM [14][15][16], even in 96-well format. An additional benefit of this procedure is an analytical process which is less prone to sample breakdown as the number of necessary analytical steps is largely reduced.…”

Healthy effect of different proportions of marine ω-3 PUFAs EPA and DHA supplementation in Wistar rats: Lipidomic biomarkers of oxidative stress and inflammation

“…In addition, COXs regulate the synthesis of strong pro-inflammatory ω-6 eicosanoids like 11HETE and PGE 2 , and less harmful ω-3 ones like TXB 3 [6]. Soybean, linseed and 1:2 groups showed significant lower GPX activities and higher hydroperoxides levels than 1:1 and 2:1 ones.…”

“…Moreover, ω-6 and ω-3 PUFAs are the main substrate of COXs, LOXs and CYP450 which produce a wide range of oxygenated lipid mediators that have been suggested as signaling molecules that may influence inflammation in a highly coordinated active process [6,7]. Specific examples include ARA eicosanoids (PGs, TXs, and LTs) [6] and IsoPs [8] which have been suggested as strong pro-inflammatory substances.…”

“…Specific examples include ARA eicosanoids (PGs, TXs, and LTs) [6] and IsoPs [8] which have been suggested as strong pro-inflammatory substances. The most studied: PGE 2 , PGF 1α , PGF 2α , TXA 2 and 8isoPGF 2α , have been associated with inflammatory stages in studies related to hypercholesterolemia, liver cirrhosis, myocardial reperfusion, type-2 diabetes, obesity, atherosclerosis, cancer, and CVD [2,3,9,10].…”

Hormetic and regulatory effects of lipid peroxidation mediators in pancreatic beta cells

“…Obligatory to phospholipid remodeling in cellular membranes is the activation of phospholipase-A enzymes that hydrolyze the acyl moieties in the sn-1 or sn-2 positions and allow for their substitution with other fatty acids. The sn-2 position is often occupied with the conditionally essential arachidonic acid that is available from the diet or through enzymatic elongation and desaturation of the essential linoleic acid (Massey and Nicolaou, 2013). The acylation of arachidonic acid and other PUFA to the sn-2 position is mediated by fatty acyl-CoA synthase and lysophospholipid acyltransferase (Shindou and Shimizu, 2009).…”