Membrane phospholipid alterations in Alzheimer's disease: Deficiency of ethanolamine plasmalogens

The ethanolamine plasmalogens are decreased whereas serine glycerophospholipids are significantly increased in plasma membrane phospholipid in affected regions of brain in Alzheimer's disease. This may be due to stimulation of Ca2+-independent plasmalogen-selective phospholipase A(2), which was recently discovered in brain. This phospholipase A(2) differs from other Ca2+-independent phospholipases A(2) in response to ATP and various inhibitors. It may be responsible for excess release of arachidonic acid and accumulation of prostaglandins and lipid peroxides in AD. Accumulation of the above lipid metabolites due to abnormal receptor function and signal transduction may contribute to neurodegeneration in AD.