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Updated: Sep 2, 2025

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

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Aβ42 oligomers trigger synaptic loss through CAMKK2-AMPK-dependent effectors coordinating mitochondrial fission and

Annie Lee1,2,3, Chandana Kondapalli1,2, Daniel M Virga1,2,4

  • 1Department of Neuroscience, Columbia University Medical Center New York, New York, NY, USA.

Nature Communications
|August 1, 2022
PubMed

Insights

Early Alzheimer's disease involves amyloid-beta oligomers causing synaptic loss by disrupting mitochondria. This study identifies a key pathway linking amyloid-beta to mitochondrial dysfunction and neuronal damage.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Biochemistry

Background:

  • Soluble amyloid-beta oligomers (Aβ42o) are implicated in early Alzheimer's disease (AD) pathogenesis.
  • Synaptic loss occurs before plaque formation in AD, particularly in cortical and hippocampal pyramidal neurons (PNs).
  • Mitochondrial structural changes and dysfunction are observed in AD models and patients.

Purpose of the Study:

  • To investigate the role of mitochondrial remodeling in early AD-related synaptic loss.
  • To identify the molecular mechanisms linking Aβ42o to synaptotoxicity.
  • To uncover the stress-response pathway mediating mitochondrial dysfunction in AD.

Main Methods:

  • Utilized a transgenic AD mouse model and a human ES cell line (APP Swe/Swe knockin).
  • Examined mitochondrial structural remodeling in CA1 PNs dendrites.
  • Assessed AMPK activation, mitochondrial fragmentation, and biomass.
  • Investigated the CAMKK2-AMPK kinase dyad's role in mediating synaptic loss via MFF and ULK2 phosphorylation.

Main Results:

  • Observed spatially restricted mitochondrial remodeling in CA1 PNs apical tufts correlating with early synaptic loss.
  • Found AMPK over-activation, increased mitochondrial fragmentation, and reduced biomass in Ngn2-induced neurons.
  • Demonstrated that Aβ42o-dependent CAMKK2-AMPK activation drives synaptic loss.
  • Showed this pathway involves MFF-dependent mitochondrial fission and ULK2-dependent mitophagy.

Conclusions:

  • Aβ42o triggers synaptic loss by inducing mitochondrial structural remodeling and dysfunction.
  • The CAMKK2-AMPK pathway is a central mediator of Aβ42o-induced synaptotoxicity.
  • This study reveals a unifying stress-response pathway linking mitochondrial dynamics to synaptic integrity in early AD.

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