Effects of dietary omega-3 polyunsaturated fatty acids on brain gene expression

TLDR

Polyunsaturated fatty acids are essential CNS structural components and are known to influence learning and memory. The study examined how perinatal omega‑3 PUFA supply and diet‑induced gene expression changes affect brain function across life stages and explored PUFA regulatory mechanisms. High‑density microarray nutrigenomics was employed to profile brain gene‑expression changes in rats fed PUFA‑enriched diets. PUFA‑enriched diets induced significant, diet‑specific changes in brain gene expression—including transthyretin, α‑synuclein, calmodulins, and various receptors and cytokines—independent of membrane composition, suggesting direct transcriptional modulation underlies their neuroprotective effects.

Abstract

Polyunsaturated fatty acids (PUFA) are essential structural components of the central nervous system. Their role in controlling learning and memory has been well documented. A nutrigenomic approach with high-density microarrays was used to reveal brain gene-expression changes in response to different PUFA-enriched diets in rats. In aged rats fed throughout life with PUFA-enriched diets, genes with altered expressions included transthyretin, α-synuclein, and calmodulins, which play important roles in synaptic plasticity and learning. The effect of perinatal omega-3 PUFA supply on gene expression later in life also was studied. Several genes showed similar changes in expression in rats fed omega-3-deficient diets in the perinatal period, regardless of whether they or their mothers were fed omega-3 PUFA-sufficient diets after giving birth. In this experiment, among the down-regulated genes were a kainate glutamate receptor and a DEAD-box polypeptide. Among the up-regulated genes were a chemokine-like factor, a tumor necrosis factor receptor, and cytochrome c . The possible involvement of the genes with altered expression attributable to different diets in different brain regions in young and aged rats and the possible mode of regulatory action of PUFA also are discussed. We conclude that PUFA-enriched diets lead to significant changes in expression of several genes in the central nervous tissue, and these effects appear to be mainly independent of their effects on membrane composition. The direct effects of PUFA on transcriptional modulators, the downstream developmentally and tissue-specifically activated elements might be one of the clues to understanding the beneficial effects of the omega-3 PUFA on the nervous system.