A synthetic peptide blocking the apolipoprotein E/beta-amyloid binding mitigates beta-amyloid toxicity and fibril formation in vitro and reduces beta-amyloid plaques in transgenic mice

Am J Pathol. 2004 Sep;165(3):937-48. doi: 10.1016/s0002-9440(10)63355-x.


Alzheimer's disease (AD) is associated with accumulation of beta-amyloid (Abeta). A major genetic risk factor for sporadic AD is inheritance of the apolipoprotein (apo) E4 allele. ApoE can act as a pathological chaperone of Abeta, promoting its conformational transformation from soluble Abeta into toxic aggregates. We determined if blocking the apoE/Abeta interaction reduces Abeta load in transgenic (Tg) AD mice. The binding site of apoE on Abeta corresponds to residues 12 to 28. To block binding, we synthesized a peptide containing these residues, but substituted valine at position 18 to proline (Abeta12-28P). This changed the peptide's properties, making it non-fibrillogenic and non-toxic. Abeta12-28P competitively blocks binding of full-length Abeta to apoE (IC50 = 36.7 nmol). Furthermore, Abeta12-28P reduces Abeta fibrillogenesis in the presence of apoE, and Abeta/apoE toxicity in cell culture. Abeta12-28P is blood-brain barrier-permeable and in AD Tg mice inhibits Abeta deposition. Tg mice treated with Abeta12-28P for 1 month had a 63.3% reduction in Abeta load in the cortex (P = 0.0043) and a 59.5% (P = 0.0087) reduction in the hippocampus comparing to age-matched control Tg mice. Antibodies against Abeta were not detected in sera of treated mice; therefore the observed therapeutic effect of Abeta12-28P cannot be attributed to an antibody clearance response. Our experiments demonstrate that compounds blocking the interaction between Abeta and its pathological chaperones may be beneficial for treatment of beta-amyloid deposition in AD.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alzheimer Disease / metabolism
  • Alzheimer Disease / pathology
  • Alzheimer Disease / prevention & control*
  • Amyloid beta-Peptides / genetics
  • Amyloid beta-Peptides / metabolism*
  • Animals
  • Apolipoproteins E / genetics
  • Apolipoproteins E / metabolism*
  • Astrocytes / metabolism
  • Astrocytes / pathology
  • Binding Sites / drug effects
  • Blood-Brain Barrier / metabolism
  • Brain / metabolism
  • Brain / pathology
  • Competitive Bidding
  • Female
  • Half-Life
  • Humans
  • Male
  • Membrane Proteins / genetics
  • Membrane Proteins / physiology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Mutation
  • Neuroblastoma / metabolism
  • Neuroblastoma / pathology
  • Peptide Fragments / pharmacology*
  • Presenilin-1
  • Protein Binding / drug effects
  • Tumor Cells, Cultured


  • Amyloid beta-Peptides
  • Apolipoproteins E
  • Membrane Proteins
  • PSEN1 protein, human
  • Peptide Fragments
  • Presenilin-1