Solid-phase synthesis and pathological evaluation of pyroglutamate amyloid-β3-42 peptide

Sci Rep. 2023 Jan 10;13(1):505. doi: 10.1038/s41598-022-26616-x.

Abstract

Pyroglutamate amyloid-β3-42 (AβpE3-42) is an N-terminally truncated and pyroglutamate-modified Aβ peptide retaining highly hydrophobic, amyloidogenic, and neurotoxic properties. In Alzheimer's disease (AD) patients, AβpE3-42 peptides accumulate into oligomers and induce cellular toxicity and synaptic dysfunction. AβpE3-42 aggregates further seed the formation of amyloid plaques, which are the pathological hallmarks of AD. Given that AβpE3-42 peptides play critical roles in the development of neurodegeneration, a reliable and reproducible synthetic access to these peptides may support pathological and medicinal studies of AD. Here, we synthesized AβpE3-42 peptides through the microwave-assisted solid-phase peptide synthesis (SPPS). Utilizing thioflavin T fluorescence assay and dot blotting analysis with anti-amyloid oligomer antibody, the amyloidogenic activity of synthesized AβpE3-42 peptides was confirmed. We further observed the cytotoxicity of AβpE3-42 aggregates in cell viability test. To examine the cognitive deficits induced by synthetic AβpE3-42 peptides, AβpE3-42 oligomers were intracerebroventricularly injected into imprinting control region mice and Y-maze and Morris water maze tests were performed. We found that AβpE3-42 aggregates altered the expression level of postsynaptic density protein 95 in cortical lysates. Collectively, we produced AβpE3-42 peptides in the microwave-assisted SPPS and evaluated the amyloidogenic and pathological function of the synthesized peptides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease* / metabolism
  • Amyloid beta-Peptides / metabolism
  • Animals
  • Mice
  • Peptide Fragments / metabolism
  • Pyrrolidonecarboxylic Acid* / metabolism
  • Solid-Phase Synthesis Techniques

Substances

  • Pyrrolidonecarboxylic Acid
  • Peptide Fragments
  • Amyloid beta-Peptides