Oxidation of phospholipids

Instead of measuring the absorbance of the solution immediately after incubation, it is possible to determine the colored product 169 by HPLC-FLD (A.ex =515 nm, /. = 553 nm). This procedure was applied for determination of MDA after oxidation of phospholipids catalyzed by soybean lipoxygenase464. Peroxidation in the extracellular liquid of the brain cortex of rats was evaluated in vivo by microdialysis followed by reaction... 

Phospholipid classes (see Section V.B.3) may be separated from one another by HPLC-UVD, measuring at 210 nm. Oxidized phospholipids, including hydroperoxide and hydroxy derivatives, can be detected by the same method measuring the signal at 234 nm. This was applied for assessment of the oxidation of phospholipids in human erythrocite membranes catalyzed by soybean lipoxydase in the presence of various modifiers464 506,507. 

Spin trapping has also been applied to the investigation of lipid peroxidation catalysed by myoglobin in linoleate emulsions,204 as well as the oxidation of phospholipids in low-density lipoproteins (18.1) by HOC1.205 Hiramoto et al. have shown that, by quenching the attacking radicals, linoleic acid can protect DNA from oxidation.206 Lipid peroxidation has also been monitored by spin labelling.207... 

Abstract. The significance of free radical oxidation of phospholipids in tissues of animals with experimental atherosclerosis was investigated. By using modem physico-chemical methods an elevated content of polyunsaturated fatty acids and other lipids peroxides was discovered in the blood and the aorta of rabbits with experimental atheromatosis. The human blood demonstrated a low level of protective enzymatic systems and a high content of products secondary to peroxidal oxidation of the lipids. The mechanism accounting for the action of lipids peroxides on the vascular wall resulting in the formation of atheromatous plaques is considered. 

There are a host of biological activities initiated by these 15-LOXl-dependent eicosanoids [31]. The unique activity of 15-LOXl in oxidizing intact phospholipids has been featured in several hypotheses linking the oxidation of phospholipids in atherosclerotic... 

Oshima, S. et al.. Inhibitory effect of p-carotene and astaxanthin on photosensitized oxidation of phospholipid bilayers, J. Nutr. Sci. VitaminoL, 39, 607, 1993. 

Liposomes tend to form aggregates in prolonged storage. A phenomenon where the membranes fuse and this causes the premature release of the carried material. Degradation reactions of lipid hydrolysis or oxidation of phospholipids, with loss of membrane function as a result, may also occur. Hence, there is a need to find a mechanism to stabilize these structures [89]. 

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