Hypochlorous acid-mediated modification of cholesterol and phospholipid: analysis of reaction products by gas chromatography-mass spectrometry.

摘要: Oxidative modification of membrane lipids by hypochlorous acid could be an important element in the mechanism disruption activated neutrophils. We have previously shown that reacts with unsaturated fatty acids phospholipids to give chlorohydrins (Winterbourn et al. 1992. Arch. Biochem. Biophys. 296: 547-555). In present study, we examined reaction cholesterol bilayers inert phospholipid carrier. Product separation and identification was performed using gas chromatography-mass spectrometry after trimethylsilyl-derivatization. Unlike acids, no chlorohydrin derivatives were found cholesterol. Instead, main oxidation products identified as epimeric 5,6-epoxides 4-hydroxycholesterol, while several other hydroxy- keto-derivatives also smaller amounts. Analysis obtained vesicles composed a mixture species plus revealed individual all exhibit comparable susceptibilities toward acid. Using myeloperoxidase generate acid, basically same product distribution obtained. These studies show can profoundly modified This warrants further investigation define role lipid modifications neutrophil-mediated disruption.