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Updated: Jun 17, 2026
06:23
Visualizing Axonal Growth Cone Collapse and Early Amyloid β Effects in Cultured Mouse Neurons
Published on: October 30, 2018
Amyloid beta from axons and dendrites reduces local spine number and plasticity
Wei Wei1, Louis N Nguyen, Helmut W Kessels
1Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.
Nature Neuroscience
|December 29, 2009
Summary
Alzheimer's disease involves synaptic loss. This study shows amyloid beta (Abeta) overproduction, from either axons or dendrites, locally reduces synapse density and plasticity, contributing to early disease.
Area of Science:
- Neuroscience
- Molecular Biology
- Pathology
Background:
- Synaptic loss is an early Alzheimer's disease (AD) event.
- Amyloid beta (Abeta) peptide is implicated in AD pathogenesis by affecting dendritic spines.
- The subcellular origin and mechanisms of Abeta's synaptic effects are unclear.
Purpose of the Study:
- Investigate the source and mechanisms of Abeta production and its impact on synaptic integrity.
- Determine the local effects of Abeta overproduction on dendritic spine density and plasticity.
Main Methods:
- Utilized rat organotypic slices to study Abeta production and effects.
- Manipulated Abeta overproduction and blocked neuronal activity (action potentials, nicotinic, NMDA receptors).
- Assessed changes in dendritic spine density and synaptic plasticity.
Main Results:
- Acute overproduction of axonal or dendritic Abeta reduced nearby spine density and plasticity.
- Abeta production and its effects were sensitive to action potential and nicotinic receptor blockade.
- Abeta's effects, but not production, were sensitive to NMDA receptor blockade.
- Blocking Abeta overproduction for 30-60 minutes restored plasticity induction.
Conclusions:
- Continuous Abeta overproduction from axons or dendrites locally impairs synapse number and plasticity.
- Neuronal activity modulates Abeta production and its subsequent impact on synaptic function.
- Findings highlight Abeta's direct role in early synaptic dysfunction in Alzheimer's disease.
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