DURING NEURONAL AND GLIAL-CELL DEVELOPMENT DIET N-6 TO N-3 FATTY-ACIDRATIO ALTERS THE FATTY-ACID COMPOSITION OF PHOSPHATIDYLINOSITOL AND PHOSPHATIDYLSERINE

Brain development was examined in the neonatal rat in response to feed ing increased levels of 18:3n - 3, 20:4n - 6 or 22:6n - 3 at levels pr oposed for infant formula. Diets varying in n - 6 to n - 3 fatty acid ratio, with or without 20:4n - 6 and 22:6n - 3 alone or in combination , were fed to nursing dams at parturition and subsequently to weaned p ups until six weeks of age. Neuronal and glial cells were isolated fro m the frontal, cerebellar and hippocampal brain regions of rat pups at birth, one, two, three and six weeks of age. Fatty acid analysis of i nositol- and serine- phosphoglycerides indicated that small changes in dietary n - 6 to n - 3 fatty acid ratio significantly affect neuronal and glial cell membrane composition. Fatty acid composition of phosph atidylinositol and phosphatidylserine was distinct and exhibited chang e with age. Individual brain regions and cell types varied in amount a nd rate of 20:4n - 6 and 22:6n - 3 accretion. Alteration of brain fatt y acid composition reflected the fatty acid composition of the diet fe d. If analogous changes occur during human brain development, feeding infants 20:4n - 6 and 22:6n - 3 or a reduced 18:2n - 6 to 18:3n - 3 ra tio may alter fatty acid profiles of brain cells. (C) 1997 Elsevier Sc ience B.V.