Life-long epigenetic programming of cortical architecture by maternal ‘ Western ’ diet during pregnancy

ABSTRACT: The evolution of human diets led to preferences towards polyunsaturated fatty acid (PUFA) content with ‘Western’ diets enriched in w-6 PUFA1. Mounting evidence points to w-6 PUFA excess limiting metabolic and cognitive processes that define longevity in humans2. When chosen during pregnancy, w-6 PUFA-enriched ‘Western’ diets can reprogram maternal bodily metabolism with maternal nutrient supply precipitating the body-wide imprinting of molecular and cellular adaptations at the level of long-range intercellular signaling networks in the unborn fetus2,3. Even though unfavorable neurological outcomes are amongst the most common complications of intrauterine w-6 PUFA excess3, cellular underpinnings of life-long modifications to brain architecture remain unknown. Here, we show that nutritional w-6 PUFA-derived endocannabinoids desensitize CB1 cannabinoid receptors, thus inducing epigenetic repression of transcriptional regulatory networks controlling neuronal differentiation. We found that cortical neurons lose their positional identity and axonal selectivity once exposing mouse fetuses to excess w-6 PUFAs in utero. Conversion of w-6 PUFAs into endocannabinoids disrupted the temporal precision of signaling at neuronal CB1 cannabinoid receptors, chiefly deregulating Stat3-dependent transcriptional cascades otherwise required to execute neuronal differentiation programs. Global proteomics identified the immunoglobulin family of cell adhesion molecules (IgCAMs) as direct substrates with DNA methylome analysis and ATAC-seq uncovering epigenetic reprogramming at >1,400 sites in neurons after prolonged cannabinoid exposure. We find anxiety and depression-like behavioral traits to manifest in adult offspring, which is compatible with genetic models of reduced IgCAM expression to suggest causality to cortical wiring defects4. Overall, our data uncover a regulatory mechanism whose disruption by maternal food choices could limit the offsprings’ brain function for life.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Brain, Early Embryonic Cell

DISEASE(S): Disease Free

SUBMITTER: Sally Shirran  

LAB HEAD: Tibor Harkany

PROVIDER: PXD016180 | Pride | 2019-11-21

REPOSITORIES: Pride