The Effects of Long-Term Saturated Fat Enriched Diets on the Brain Lipidome

PLoS One. 2016 Dec 1;11(12):e0166964. doi: 10.1371/journal.pone.0166964. eCollection 2016.

Abstract

The brain is highly enriched in lipids, where they influence neurotransmission, synaptic plasticity and inflammation. Non-pathological modulation of the brain lipidome has not been previously reported and few studies have investigated the interplay between plasma lipid homeostasis relative to cerebral lipids. This study explored whether changes in plasma lipids induced by chronic consumption of a well-tolerated diet enriched in saturated fatty acids (SFA) was associated with parallel changes in cerebral lipid homeostasis. Male C57Bl/6 mice were fed regular chow or the SFA diet for six months. Plasma, hippocampus (HPF) and cerebral cortex (CTX) lipids were analysed by LC-ESI-MS/MS. A total of 348 lipid species were determined, comprising 25 lipid classes. The general abundance of HPF and CTX lipids was comparable in SFA fed mice versus controls, despite substantial differences in plasma lipid-class abundance. However, significant differences in 50 specific lipid species were identified as a consequence of SFA treatment, restricted to phosphatidylcholine (PC), phosphatidylethanolamine (PE), alkyl-PC, alkenyl-PC, alkyl-PE, alkenyl-PE, cholesterol ester (CE), diacylglycerol (DG), phosphatidylinositol (PI) and phosphatidylserine (PS) classes. Partial least squares regression of the HPF/CTX lipidome versus plasma lipidome revealed the plasma lipidome could account for a substantial proportion of variation. The findings demonstrate that cerebral abundance of specific lipid species is strongly associated with plasma lipid homeostasis.

MeSH terms

  • Animals
  • Brain Chemistry / drug effects*
  • Cerebral Cortex / chemistry
  • Cerebral Cortex / metabolism
  • Cholesterol Esters / metabolism
  • Diet, High-Fat*
  • Diglycerides / metabolism
  • Fatty Acids / administration & dosage
  • Fatty Acids / metabolism*
  • Hippocampus / chemistry
  • Hippocampus / metabolism
  • Lipid Metabolism / drug effects*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Phosphatidylcholines / metabolism
  • Phosphatidylethanolamines / metabolism
  • Phosphatidylinositols / metabolism
  • Phosphatidylserines / metabolism
  • Time Factors

Substances

  • Cholesterol Esters
  • Diglycerides
  • Fatty Acids
  • Phosphatidylcholines
  • Phosphatidylethanolamines
  • Phosphatidylinositols
  • Phosphatidylserines
  • phosphatidylethanolamine

Grants and funding

JM acknowledges the Australian National Health and Medical Research Council (www.nhmrc.gov.au) Project grant 1064567. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.