A Short-Term Western Diet Impairs Cholesterol Homeostasis and Key Players of Beta Amyloid Metabolism in Brain of Middle Aged Rats

Mol Nutr Food Res. 2020 Aug;64(16):e2000541. doi: 10.1002/mnfr.202000541. Epub 2020 Jul 20.

Abstract

Scope: Cholesterol homeostasis is crucial for brain functioning. Unhealthy nutrition can influence cerebral physiology, but the effect of western diets on brain cholesterol homeostasis, particularly at middle age, is unknown. Given the link between brain cholesterol alteration and beta amyloid production, the aim is to evaluate whether a diet rich in fat and fructose affects the protein network implicated in cholesterol synthesis and shuttling between glial cells and neurons, as well as crucial markers of beta amyloid metabolism.

Methods and results: Middle aged rats are fed a high fat-high fructose (HFF) or a control diet for 4 weeks. Inflammatory markers and cholesterol levels significantly increase in hippocampus of HFF rats. A higher activation of 3-hydroxy 3-methylglutaryl coenzyme-A reductase, coupled with lower levels of apolipoprotein E, LXR-beta, and lipoproteins receptors is measured in hippocampus from HFF rats. The alteration of critical players of cholesterol homeostasis is associated with increased level of amyloid precursor protein, presenilin 1, and nicastrin, and decreased level of insulin degrading enzyme.

Conclusions: Overall these data show that a western diet is associated with perturbation of cholesterol homeostasis in middle aged rats, mostly in hippocampus. This might trigger molecular events involved in the onset of neurodegenerative diseases.

Keywords: apolipoprotein E; cholesterol; high fat-high fructose diet; hippocampus; middle age.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Amyloid Precursor Protein Secretases / metabolism
  • Amyloid beta-Peptides / metabolism*
  • Animals
  • Apolipoproteins E / metabolism
  • Blood-Brain Barrier / physiology
  • Brain / metabolism*
  • Brain / physiopathology
  • Cholesterol / metabolism*
  • Cholesterol 24-Hydroxylase / metabolism
  • Diet, Western / adverse effects*
  • Fructose / adverse effects
  • Homeostasis
  • Hydroxymethylglutaryl CoA Reductases / metabolism
  • Liver X Receptors / metabolism
  • Low Density Lipoprotein Receptor-Related Protein-1 / metabolism
  • Membrane Glycoproteins / metabolism
  • Rats, Sprague-Dawley
  • Receptors, LDL / metabolism
  • Sterol Regulatory Element Binding Protein 2 / metabolism

Substances

  • Amyloid beta-Peptides
  • Apolipoproteins E
  • Liver X Receptors
  • Low Density Lipoprotein Receptor-Related Protein-1
  • Membrane Glycoproteins
  • Nr1h2 protein, rat
  • Receptors, LDL
  • Sterol Regulatory Element Binding Protein 2
  • nicastrin protein
  • Fructose
  • Cholesterol
  • Hydroxymethylglutaryl CoA Reductases
  • Cholesterol 24-Hydroxylase
  • Amyloid Precursor Protein Secretases