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Updated: May 17, 2026

Preparation of Oligomeric β-amyloid1-42 and Induction of Synaptic Plasticity Impairment on Hippocampal Slices
04:41

Preparation of Oligomeric β-amyloid1-42 and Induction of Synaptic Plasticity Impairment on Hippocampal Slices

Published on: July 14, 2010

Effects of different amyloid β-protein analogues on synaptic function

Cristian Ripoli1, Roberto Piacentini, Elisa Riccardi

  • 1Institute of Human Physiology, Università Cattolica, Rome, Italy.

Neurobiology of Aging
|October 11, 2012
PubMed

Insights

Oxidation of methionine 35 in amyloid-beta 42 (Aβ42) is critical for its toxic effects on synapses in Alzheimer's disease. This oxidation prevents Aβ42 from impairing synaptic function and structure.

Area of Science:

  • Neuroscience
  • Molecular Biology
  • Biochemistry

Background:

  • Perisynaptic amyloid-beta protein (Aβ) aggregates are implicated in Alzheimer's disease (AD) cognitive decline.
  • Oxidation of methionine at position 35 (Met35) in Aβ is a hallmark of AD brains.

Purpose of the Study:

  • To investigate the role of Met35 oxidation in Aβ42-induced synaptotoxicity.
  • To determine if oxidized Aβ42 (Met35 sulfoxide) retains its ability to impair synaptic function.

Main Methods:

  • Electrophysiological recordings in hippocampal slices and autaptic neurons.
  • Assessment of synaptic transmission, including long-term potentiation and basal synaptic transmission.
  • Evaluation of Aβ42 effects on dendritic spine density and key pre- and postsynaptic protein expression.

Main Results:

  • Wild-type Aβ42 significantly inhibited long-term potentiation and basal synaptic transmission, reducing excitatory postsynaptic current amplitude, vesicle release probability, and miniature excitatory postsynaptic current frequency.
  • Aβ42 with oxidized Met35 (Met35 sulfoxide) did not cause these impairments.
  • Extended Aβ exposure affected presynaptic and postsynaptic function, dendritic spine density, and protein expression, with oxidized Aβ42 showing reduced impact.

Conclusions:

  • Oxidation of Met35 is crucial for the molecular, structural, and functional synaptotoxicity of Aβ42.
  • Targeting Met35 oxidation could be a therapeutic strategy for Alzheimer's disease.

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