Abstract
The latest findings on polyunsaturated oil ingestion and phospholipid hydroperoxidation in biomembranes will be reviewed in this article from a view angle of membrane structures.
Phospholipids, especially of aminolipids like phosphatidylethanolamine and phosphatidylserine, show potent antioxidant effects synergetically with endogenous tocopherols on autoxidation of dietary polyunsaturated oils, among which oxidation of perilla oil rich in α-linolenate is prevented by the presence of trace amount of aminolipids. This finding may also imply the importance of constituent phospholipids as antioxidant molecules with α-tocopherol in biomembranes. Among the physical conformations of phospholipid bilayers, hexagonal II phase is more susceptible to autoxidation than lamellar bilayer structures, thus suggesting that the hydroperoxidation proceeds rather on more dynamic non-bilayer phase transitions. For clinical interests, we could observe an abnormal accumulation of phospholipid hydroperoxides in red blood cell membranes of human senile dementia, in which phospholipid molecules containing icosapentaenoate and docosahexanoate are presumed to be the most peroxidizable membrane lipids in the dementia erythrocytes.
With due regarding to those findings as cited here, the dietary treatment of polyunsaturated oils such as fish oil ingestion would need more careful consideration based on further studies from a viewpoint of membrane lipid hydroperoxidation and human health.
