F-4-isoprostanes as specific marker of docosahexaenoic acid peroxidation in Alzheimer's disease

F-2-isoprostanes are prostaglandin-like compounds derived from free radical -catalysed peroxidation of arachidonic acid. Peroxidation of eicosapentaeno ic acid produces F-3-isoprostanes, whereas peroxidation of docosahexaenoic acid would give F-4-isoprostanes. This study demonstrates the presence of e sterified F-4-isoprostanes in human brain and shows that levels are elevate d in certain brain cortex regions in Alzheimer's disease. Our data with Alz heimer's disease suggest that analysis of F-4-isoprostanes will provide new opportunities to study lipid peroxidation in the neurodegenerative disease s.