Lipidomics derivatives

D1 (10,17S-docosatriene) from DHA using tandem liquid chromatography-photodiode array-electrospray ionization-tandem mass spectrometry (LC-PDA-ESI-MS-MS)-based lipidomic analysis have been documented in ischemic brain [4] and retinal pigment epithelium [5], This new lipid is called neuroprotectin D1 (1) because of its neuro-protectiveproperties in brain ischemia-reperfusion [4] and in oxidative stress-challenged retinal pigment epithelial cells [5] (2) because of its potent ability to inactivate proapoptotic signaling (see apoptosis, Ch. 35) [5] and (3) because it is the first identified neuroprotective mediator derived from DHA. 

DAG species are derived from three main routes (1) PLC-mediated hydrolysis of phospholipids (2) phosphatase-mediated hydrolysis of phosphatidic acid (PA) and (3) lipase-mediated hydrolysis of triacylglycerol (TAG) species (Fig. 2). Targeted lipidomic analyses show that the fatty acid compositions of the DAGs formed by these various routes reflect the composition of the parent lipid (Fig. 5). In particular, those derived from inositol phospholipids are highly enriched in... 

Lee et al. [41] developed a method for the quantitative analysis of enantiomers and regioisomers of fatty acids, hydroxy fatty acids, and related substances, including several HETEs and prostaglandins. The method is based on pre-column derivatization to pentafluorobenzyl derivatives and subsequent LC-MS analysis in an organic mobile phase using electron-capture negative-ionization (ECNI). The method is applied to lipidomic profiling, for instance of rat epithehal cells. 

Massey, K. A. and Nicolaou, A. 2011. Lipidomics of polyunsaturated-fatty-acid-derived oxygenated metabolites. BwchemSocTmm 39, 1240-6. 

Dumlao, D.S., Buczynski, M.W., Norris, P.C., Harkewicz, R., and Dennis, E.A. (2011) High-throughput lipidomic analysis of fatty acid derived eicosanoids and N-acylethanolamines. Biochim. Bio-phys. Acta, 1811 (11), 724-736. doi 10.1016/j.bbalip.2011.06.005... 

Although many systematic indices (e.g.. Lipid MAPS, Chemical Entries of Biological Interest (ChEBI), lUPAC International Chemical Identifiers (InChl), simplified molecular-input line entry system (SMILES)) were developed to list the chemical compounds, these indices (identifiers) can only be meaningful if the compound is totally identified. However, in practice, lipidomics analysis in many cases can only provide partial identification of lipid molecular structures at the current development of technology. Moreover, different lipidomics approaches provide different levels of stmctural identification of lipid species. Therefore, how to clearly express and report the information about the levels of identification for the structures of lipid species (which can be derived fi om MS analysis) is not only helpful for the readers but also important for bioinformatics and data communication. To this end, the analysis by shotgun lipidomics could be used as a typical example to explain these levels. Similar phenomena also exist in the analysis of lipid species employing LC-MS-based approaches. 

To reflect these different levels of structural information, a system of shorthand notation for lipid structures derived from MS analysis was proposed [39] and becomes widely accepted. For example, for analysis of PC species, it was proposed to notate with PC(nominal mass) or PC(m n) to represent a detected species by the tandem MS approach (where m and n are the total number of carbon atoms and double bonds of aliphatic chains in the species, respectively) with PC(mi i i2 2) or PC(o-mi ni m2 2) to reflect the identification of individual fatty acyl chains and the ether bond by the high mass resolution mass spectrometry-based shotgun lipidomics and with VCim1.n1lm2.n2) or VCio-m1.n1lm2.n2) to denote the total identification of PC species by MDMS-SL. Similarly, MRM-based methods after... 

Kawai, Y, Takeda, S. and Terao, J. (2007) Lipidomic analysis for lipid peroxidation-derived aldehydes using gas chromatography-mass spectrometry. Chem. Res. Toxicol. 20, 99-107. 

In this aspect, novel anti-inflammatory mediators, including resolvins and protectins derived from docosahexaenoic acid (DHA, 22 6 FA), are discovered in association with the beneficial effects of dietary DHA on prevention of cardiovascular diseases [37, 38], In contrast, lipidomics research further confirmed the association of a variety of eicosanoids, oxylipins, and endocannabinoids with initiation and progression of cardiovascular diseases [39], These studies strongly suggest that the levels of n-3 and n-6 PUFA should be well balanced. 

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