|POULOSE, SHIBU - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|BIELINSKI, DONNA - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|CROTT, JIMMY - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|ROE, ANNIE - Tufts University|
Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: 1/28/2015
Publication Date: 4/1/2015
Citation: Poulose, S.M., Bielinski, D.F., Crott, J.W., Roe, A.J., Thangthaeng, N., Shukitt Hale, B. 2015. Effects of aging and walnut diet on DNA methylation and expression of immediate-early genes in critical brain regions. Federation of American Societies for Experimental Biology Conference. FASEB Journal - EB abstracts 2015.
Technical Abstract: Emerging evidence indicates a direct link between age-associated changes in epigenetic mechanisms and onset of neurodegenerative diseases, and that these genomic modulations are directly affected by the diet. Diets deficient in folate, choline and methionine, or the trace elements zinc and selenium, are reported to induce DNA hypomethylation and are linked to aberrant gene transcription. In a cognitively healthy adult, transcription of immediate-early genes (IEGs), e.g., Arc (activity-regulated cytoskeletal gene), zif268 (nerve growth factor inducible-A), bdnf (brain-derived neurotrophic factor) and Reln (plasticity-promoting Reelin) are essential in memory formation and synaptic plasticity. In the current study, we investigated the effect of walnut diets, which are rich in polyunsaturated fatty acids and nutrients such as folates, selenium, magnesium and polyphenolics, on epigenetic mechanisms in critical regions of the brain. Young (3 months, n=30, 10/group) and old (19 months, n=45, 15/group) male Fischer 344 rats were supplemented with control (0%), 6% or 9% walnut diets for 10 weeks. Using LC-MS, absolute amounts of deoxycytidine and methylated cytosine residues in genomic DNA were quantified. Using RT-PCR, expression of bdnf, zif268, reln and arc were measured in hippocampus and frontal cortex. Significant aging effects (p<0.05) were observed for the expression of bdnf, zif268, reln and arc. The 9% walnut diet significantly (p<0.01) increased the expression of zif268 in the hippocampus compared to control animals. The results suggest that dietary walnut may have protective effects on the aging brain.