Brad Feltham - March 20

A Diet High in Omega-3 Polyunsaturated Fatty Acids Alters the Fatty Acid Composition of the Brain and Regulates the Expression of Neurotrophins

Omega (n)-3 polyunsaturated fatty acids (PUFA) are known to regulate neuronal function; however, it is not known whether the effects are sex specific. Furthermore, it is not known whether a diet high in n-3 PUFA alters the accretion of various fatty acids in different regions of the brain, and if the effects are sex and age dependent. Using C57BL/6 mice, we investigated the effects of high dietary n-3 PUFA on the fatty acid composition of cortex, brain stem and cerebellum. We also explored the mechanisms by which n-3 PUFA regulate the expression of neurotrophins such as brain derived neurotrophic factor (BDNF). Regardless of diet, both females and males showed a reduction in the amount of saturated fatty acids in the cerebellum and brainstem with age, and a subsequent increase in the amount of monounsaturated fatty acids. BDNF mRNA expression was higher in the females, and the expression increased with age in both males and females; however, there was no effect of diet. Treatment of primary cortical neurons with docosahexaenoic acid (DHA) showed an increase in BDNF mRNA expression, while other fatty acids had no effect. Our findings demonstrate age and sex-specific changes in the fatty acid composition and neurotrophin expression in different regions of the brain.