Perinatal and post‐weaning diets high in omega‐3 fatty acids upregulate genes involved in neurotrophin signaling

Abstract

We investigated the effects of perinatal and post‐weaning diets high in omega (n)‐3 polyunsaturated fatty acids (PUFA) on cerebral cortical phospholipid fatty acid composition, and the impact on mRNA expression of neurotrophins. Female C57BL/6 mice were fed semi‐purified diets (20% w/w fat) containing n‐6 to n‐3 PUFA ratios of 5:1 (high n‐3 PUFA) or 30:1 (low n‐3 PUFA) before mating, during pregnancy, and until weaning. Male offspring (n=8) continued on their mothers’ diets for four months. Brain cortex phospholipid fatty acids were determined by thin layer and gas chromatography, and mRNA expressions of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), cAMP response element binding protein (CREB), and TrkB were measured at weaning and four months. Docosahexanoic acid and total n‐3 PUFA were significantly higher in cortical phospholipids of the high n‐3 PUFA group compared to the low n‐3 PUFA group at weaning (P<0.0001), and at four months (P<0.05). The high n‐3 PUFA group showed a trend towards an increase in mRNA expressions of BDNF, NGF, and TrKB at weaning, however a significant (P<0.0001) increase was observed at four months in the high n‐3 PUFA group compared to low n‐3 PUFA group. Our data shows that accretion of n‐3 PUFA in the brain upregulates gene expression of neurotrophins and their target receptors, thereby stimulating neuroprotection and enhanced cognitive function. Supported by NSERCGrant Funding Source: NSERC