Several studies suggest a negative association between omega-3 fatty acids (n-3 FA) intake and Alzheimer’s disease or cognitive decline. However, clinical trials using n-3 FA supplements are inconsistent. This could be due to a slower response in individuals carrying the ε4 allele of APOE (APOE4) compared to non-carriers.
In this pilot study, we aimed to determine whether two or four months of supplementation with an oil enriched in n-3 FA-containing lysophosphatidylcholine (LPC n-3 FA) would be sufficient to increase docosahexaenoic acid (DHA, 22:6n-3) in the cortex of APOE3 and APOE4 mice.
APOE3 and APOE4 mice were given an oil enriched with LPC n-3 FA or a control oil for two or four months (n = 5-8/genotype/diet/duration). They were then sacrificed, and frontal cortices were collected. Concentrations in phospholipids were measured using liquid chromatography coupled with mass spectrometry.
Following four months of supplementation with LPC n-3 FA, the level of total DHA were higher in APOE3 mice, but not in APOE4 mice, compared to control. This could be due to higher levels of PC 16:0_22:6 (p=0.0032), PC 18:0_22:6 (p=0.0215) and PC 18:1_22:6 (p=0.0106). In APOE3 mice supplemented with LPC n-3 FA but only for two months, the difference in those lipids did not reach statistical significance (p=0.0673, p=0.1643 and p=0.0922 respectively).
Our results show that four months of supplementation is required to induce a significant increase of DHA-containing lipids in the frontal cortices of APOE3 mice. APOE4 mice may require a longer supplementation.
I started as a pharmacy student at Université Paris Descartes in 2016. My interest in understanding the mechanisms underlying therapeutical strategies led me to register for an introductory path to research. I had the opportunity to develop my knowledge in biochemistry and in behaviour while working on mice and drosophila during internships, but my area of research was always related to the brain. In January 2022, I joined Pre Mélanie Plourde’s lab at the Centre de Recherche sur le Vieillissement as a PhD student of Université de Sherbrooke. My project focuses on the crossing of omega-3 fatty acids through blood-to-brain interfaces, namely the blood-brain barrier and the choroid plexuses, in a mouse model of Alzheimer’s disease. This project aims to connect lipidomic data in those structures with their transcriptomic profile. In January 2023, I published a scoping review paper on randomised controlled trials assessing the efficacy of omega-3 fatty acids supplements in improving cognitive scores in Ageing Reviews.