[Influence of phospholipids on oxidation of the methylester of oleic acid]. / Vliianie fosfolipidov na okislenie metilovogo éfira oleinovoi kisloty

It has been shown on the model of thermic oxidation of oleic acid methyl ether that addition of phosphatidylethanolamine and lisophosphatidylcholine into a developed reaction brings about some regularities which can be accounted for as oxidation of two-substances. It is suggested that phospholipids can be the substrate of radical oxidation of substances in oxidative transformations of lipids in the cell. In this case according to oxidation conditions the same phospholipids can appear either as prooxidants or as antioxidants.

[Comparative study of changes in the concentration of free cholesterol and antioxidative activity of lipids from animal tissues]. / Sravnitel'noe izuchenie izmenenii kontsentratsii svobodnogo kholesterina i antiokislitel'noi aktivnosti lipidov zhivotnykh tkanei

An inverse correlation was observed between the alterations in concentration of free cholesterol and an antioxidative activity of lipids in several tissues and cells. The effect was studied in mice liver tissue on reparative regeneration after partial hepatectomy, in intact mice liver under the directed action on the system of free radical reactions of cell lipid oxidation and in a culture of Hela cells during various periods of cell cycle. Using as a model system the thermal oxidation of oleic acid methyl ester cholesterol was found to function as a substrate in the reactions of free-radical cooxidation and the products of oxidation of cholesterol were active as antioxidants. The significance of a system containing cholesterol and its oxidizing products is discussed in connection with the metabolism of cholesterol itself and in reactions, related to alteration in free-radical oxidation of cell lipids.