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Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model
Published on: July 26, 2011
Platelet membrane abnormality in Alzheimer's disease
G S Zubenko1, B M Cohen, F Boller
1Department of Psychiatry, University of Pittsburgh School of Medicine, PA.
Annals of Neurology
|August 1, 1987
Summary
Alzheimer's disease patients show altered platelet membrane fluidity, specifically increased fluidity in the hydrocarbon region, which correlates with dementia severity. This finding challenges the accelerated aging hypothesis for Alzheimer's disease.
Area of Science:
- Neuroscience
- Biochemistry
- Cell Biology
Background:
- Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline.
- Altered cell membrane properties have been implicated in AD pathogenesis.
- The relationship between membrane fluidity and AD progression requires further investigation.
Purpose of the Study:
- To investigate differences in platelet and red cell membrane fluidity between individuals with probable Alzheimer's disease and healthy controls.
- To explore the correlation between altered membrane fluidity and clinical parameters of Alzheimer's disease, such as severity and duration.
- To assess whether observed membrane changes support or refute the accelerated aging hypothesis in Alzheimer's disease.
Main Methods:
- Double-blind fluorescence studies using platelet and red cell membranes from 24 probable AD patients and 36 healthy controls.
- Lipid probes 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene (TMA-DPH) were used to measure membrane fluidity at 37°C.
- Fluorescence spectroscopy determined the rotation rates and steady-state anisotropy of the lipid probes.
Main Results:
- Platelet membrane fluidity, specifically in the hydrocarbon region probed by DPH, was significantly increased in Alzheimer's disease patients compared to controls (p < 0.0001).
- No significant difference in TMA-DPH rotation rates was observed, indicating normal fluidity at the lipid-aqueous interface.
- Increased DPH fluidity in platelet membranes strongly correlated with the severity of dementia (p < 0.0001).
Conclusions:
- Alzheimer's disease is associated with abnormal platelet membrane fluidity, characterized by increased fluidity in the hydrocarbon region.
- The observed membrane alterations do not support the hypothesis that Alzheimer's disease is caused by accelerated normal aging.
- Platelet membrane fluidity may serve as a potential biomarker for Alzheimer's disease severity.
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