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Biochemical Purification and Proteomic Characterization of Amyloid Fibril Cores from the Brain
Published on: April 28, 2022
The synaptic proteome in Alzheimer's disease
Rachel Yoon Kyung Chang1, Amanda S Nouwens, Peter R Dodd
1School of Chemistry and Molecular Biosciences, University of Queensland, Australia.
Alzheimer'S & Dementia : the Journal of the Alzheimer'S Association
|November 17, 2012
Summary
Researchers identified 26 synaptic proteins with altered expression in Alzheimer's disease (AD) brains. This discovery aids understanding of synaptic dysfunction mechanisms and potential therapeutic targets for AD progression.
Area of Science:
- Neuroscience
- Proteomics
- Biochemistry
Background:
- Synaptic dysfunction is an early hallmark of Alzheimer's disease (AD), directly correlating with cognitive decline.
- Understanding the molecular basis of synaptic degeneration is crucial for developing effective AD treatments.
- Identifying specific synaptic proteins altered in AD may reveal key pathogenic pathways.
Purpose of the Study:
- To compare synaptic protein expression in Alzheimer's disease (AD) brain tissue versus non-AD controls.
- To identify specific synaptic proteins that are differentially expressed in AD.
- To elucidate molecular mechanisms underlying synaptic dysfunction in AD.
Main Methods:
- Proteomic analysis using two-dimensional differential in-gel electrophoresis on synaptosomal fractions from human autopsy brain tissue.
- Comparison of vulnerable (hippocampus, temporal cortex) and spared (motor, occipital cortex) brain regions in AD and control subjects.
- Identification of significantly changed proteins (≥20% change) via mass spectrometry.
Main Results:
- Twenty-six distinct synaptic proteins showed more than twofold expression changes between AD and normal subjects.
- These proteins are implicated in critical cellular functions such as energy metabolism, signal transduction, and vesicle transport.
- Significant alterations in synaptic protein expression were observed in AD brain.
Conclusions:
- Comparative proteomic analysis successfully identified novel markers of pathogenic mechanisms in synaptic dysfunction.
- The findings provide insights into the molecular underpinnings of synaptic degeneration in Alzheimer's disease.
- These identified proteins represent potential therapeutic targets for slowing AD progression.
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