Impact of 27-Hydroxycholesterol on Amyloid-β Peptide Production and ATP-Binding Cassette Transporter Expression in Primary Human Neurons Academic Article uri icon


  • Cholesterol is an integral component of neuronal membranes and recent evidence has shown that it regulates amyloid-beta protein precursor processing to form amyloid-beta peptides, which are a major constituent of cerebral amyloid plaques associated with Alzheimer's disease. 27-Hydroxycholesterol (27OHC) is synthesized from cholesterol via sterol 27-hydroxylase (CYP27A1) in the brain and, unlike cholesterol, can cross into the brain through the blood brain barrier from the circulation. Previous studies point toward a potential role for 27OHC in the regulation of neuronal amyloid-beta peptide generation, however, this has not been investigated in primary human neurons. Here we show that 27OHC significantly reduced amyloid-beta peptide detected in cell culture supernatants from primary human neurons. We also show that 27OHC does not affect alpha-, beta- or gamma-secretase activity but does upregulate the liver X receptor (LXR) responsive genes ABCA1, ABCG1 and APOE. These data suggest that 27OHC-mediated reduction in extracellular amyloid-beta peptide levels is potentially due to its action as an LXR ligand.


  • Scott Kim, Woojin
  • Chan, Sharon L
  • Hill, Andrew F
  • Guillemin, Gilles J
  • Garner, Brett

publication date

  • January 4, 2009

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