Lipid peroxidation products identification

Thus the main part of this review will deal with the recognition, identification, structures and physiological properties of lipid peroxidation (LPO) products which seem also linked with programmed cell death and necrosis. These events and the chemistry of these reactions will be outlined in the final section of this review. 

It is important to note that the modifications generated by those lipid oxidation products contribute nearly to the same extent to DNA damage than the direct oxidized bases (Winczura et al. 2012). These lipid peroxidation aldehydes-DNA adducts have been reported in vivo in rodent and human DNA, in a wide variety of organs and tissue. For most of them, they can be found at a basal state (Marnett 1999 Nair et al. 1999, 2007), but their concentration is increased in the case of oxidative stress due, for instance, to inflammatory processes (Nair et al. 2007), but also in the case of PUFA-rich diet (Fang et al. 2007). For etheno-adducts, most of the studies report the presence of unsubstituted adducts, making the identification of the reactant enal impossible. However, a substituted etheno-adduct specific to the lipid oxidation product 4-oxo-nonenal has been found in greater amounts in the small intestine of mice prone to intestinal cancer (Min mice) and overexpressing the enzyme COX-2 involved in inflammatory processes than in the small intestine of control mice (Williams et al. 2006). 

Oxygenated acylglycerols. Lipid peroxidation in biological tissues attracts much attention because of its possible contribution to the functional modulation of biomembranes and lipoproteins. It is believed to be involved in free-radical-mediated damage, carcinogenesis and ageing processes. Research requires specific, sensitive and reproducible procedures to quantify the lipid hydroperoxides in each lipid class as primary products and the alcohols and aldehydes as secondary products of the peroxidation reaction. The identification and quantification of lipid oxidation products is therefore of great practical and theoretical interest and MS has assumed a major role in these analyses as a result of the development of mild ionization techniques. 

Kamido, H., Kuksis, A., Marai, L. and Myher, J. J. (1993) Identification of core aldehydes among in vitro peroxidation products of cholesteryl esters. Lipids, 28, 331-6. 

MUne, G. L. and Porter, N. Separation and identification of phosphohpid peroxidation products. Lipids 36, 1265—1275 (2001). 

Benedetti A, Comporti M, Esterbauer H (1980) Identification of 4-hydroxynonenal as a cytotoxic product originating from the peroxidation of liver microsomal lipids, Biochim Biophys Acta 620 281-296... 

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