Synthetically prepared Aamadori-glycated phosphatidylethanolaminecan trigger lipid peroxidation via free radical reactions

This study for the first time confirmed the peroxidative role of the Amadori product derived from the glycation of phosphatidylethanolamine (PE), namely Amadori-PE. The product was synthesized from the reaction of dioleoyl PE with D-glucose, and then purified by a solid-phase extraction procedure, which was a key step in the next HPLC technique for the isolation of essentially pure Amadori-PE. When the synthetically prepared Amadori-PE was incubated with linoleic acid in the presence of Fe(3+) in micellar system, a remarkable formation of thiobarbituric acid reactive substances was observed together with increases in lipid hydroperoxides. In addition, the lipid peroxidation caused by Amadori-PE was effectively inhibited by superoxide dismutase, mannitol, catalase and metal chelator. These results indicated that Amadori-PE triggers oxidative modification of lipids via the generation of superoxide, and implied the involvement of 'lipid glycation' along with membrane lipid peroxidation in the pathogenesis of diabetes and aging.