Effects of Dietary Supplementation with EPA-enriched Phosphatidylcholine and Phosphatidylethanolamine on Glycerophospholipid Profile in Cerebral Cortex of SAMP8 Mice fed with High-fat Diet

The destruction of lipid homeostasis is associated with nervous system diseases such as Alzheimer's disease (AD). It has been reported that dietary EPA-enriched phosphatidylcholine (EPA-PC) and phosphatidylethanolamine (EPA-PE) could improve brain function. However, it was unclear that whether EPA-PC and EPA-PE intervention could change the lipid composition of cerebral cortex in AD mice. All the senescence-accelerated mouse-prone 8 (SAMP8) mice were fed with a high-fat diet for 8 weeks. After another 8 weeks of intervention with EPA-PC and EPA-PE (1%, w/w), the cerebral cortex lipid levels were determined by lipidomics. Results demonstrated that dietary supplementation with EPA-PE and EPA PC for 8 weeks significantly increased the amount of choline plasmalogen (pPC) and Lyso phosphatidylethanolamine (LPE) in the cerebral cortex of SAMP8 mice fed with high fat diet. Meanwhile, administration with EPA-PE and EPA-PC could significantly decrease the level of docosapentaenoic acid (DPA)-containing phosphatidylserine (PS) as well as increase the levels of arachidonic acid (AA)-containing phosphatidylethanolamine and PS in cerebral cortex. EPA-PE and EPA-PC could restore the lipid homeostasis of dementia mice to a certain degree, which might provide a potential novel therapy strategy and direction of dietary intervention in patients with cognitive impairment.

Recovery of brain DHA-containing phosphatidylserine and ethanolamine plasmalogen after dietary DHA-enriched phosphatidylcholine and phosphatidylserine in SAMP8 mice fed with high-fat diet

Background

Glycerophospholipids were the main components of cerebral cortex lipids, and there was a close association between lipid homeostasis and human health. It has been reported that dietary DHA-enriched phosphatidylcholine (DHA-PC) and phosphatidylserine (DHA-PS) could improve brain function. However, it was unclear that whether supplementation of DHA-PC and DHA-PS could change lipid profiles in the brain of dementia animals.

Methods

SAMP8 mice was fed with different diet patterns for 2 months, including high-fat diet and low-fat diet. After intervention with DHA-PC and DHA-PS for another 2 months, the lipid profile in cerebral cortex was determined by lipidomics in dementia mice.

Results

High-fat diet could significantly decrease the levels of DHA-containing PS/pPE, DPA-containing PS, and AA-containing PE, which might exhibit the potential of lipid biomarkers for the prevention and diagnosis of AD. Notably, DHA-PC and DHA-PS remarkably recovered the lipid homeostasis in dementia mice. These might provide a potential novel therapy strategy and direction of dietary intervention for patients with cognitive decline.

Conclusions

DHA-PC and DHA-PS could recover the content of brain DHA-containing PS and pPE in SAMP8 mice fed with high-fat diet.

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Digestion, Absorption, and Metabolism Characteristics of EPA-Enriched Phosphoethanolamine Plasmalogens Based on Gastrointestinal Functions in Healthy Mice

EPA-enriched phosphoethanolamine plasmalogens (EPA-pPE), widely present in marine creatures, is a unique glycerophospholipid with EPA at the sn-2 position of the glycerol backbone. EPA-pPE has been reported to exhibit numerous distinctive bioactivities. However, the digestion, absorption, and metabolism characteristics of EPA-pPE in vivo are not clear, which restrict the molecular mechanism analysis related to its distinctive activities. The aim of the present study was to illustrate the digestion, absorption, and metabolism characteristics of EPA-pPE by lipid analysis in serum, intestinal wall, and content after oral administration of EPA-pPE emulsion. Results showed the EPA percentage of total fatty acids in serum was increasing over time, with two peaks at 5 and 10 h by 1.89 ± 0.2 and 2.58 ± 0.27, respectively, and then fell from 1.89 ± 0.17 at 10 h to 1.35 ± 0.16 at 16 h. In small intestinal content, EPA-pPE was hydrolyzed to lyso-phospholipids and EPA by phospholipases A2 and the vinyl ether bond was retained at the sn-1 position. The released EPA could be quickly taken up into the enterocytes and enter circulation. The comparison of simulated digestion in vitro showed that the distinct digestion and absorption process of EPA-pPE was a unique phenomenon. EPA could be retained in serum at a high level for a substantial period of time, which suggested that EPA-pPE was not just a short-lived circulating molecule.