Related Experiment Videos
Moderate and advanced Alzheimer's patients exhibit platelet activation differences
T A Davies1, H J Long, H E Tibbles
1Department of Biochemistry, Boston University School of Medicine, MA 02118, USA.
Neurobiology of Aging
|March 1, 1997
Summary
Platelets from moderate Alzheimer's disease (AD) patients show normal signal transduction and amyloid precursor protein (APP) processing. These platelet defects appear only in advanced AD stages.
Area of Science:
- Neuroscience
- Hematology
- Biochemistry
Background:
- Platelets from advanced Alzheimer's disease (AD) patients exhibit aberrant signal transduction (thrombin-induced hyperacidification) and Amyloid Precursor Protein (APP) processing defects.
- These defects include hyperacidification severity correlating with the apolipoprotein E4 (apoE4) allele and APP retention on activated platelets, independent of apoE4.
- The retention of membrane APP is linked to reduced soluble APP release.
Purpose of the Study:
- To investigate the disease stage at which platelet defects manifest in Alzheimer's disease (AD).
- To determine if moderate AD patients exhibit the previously reported platelet abnormalities.
Main Methods:
- Signal transduction studies were performed on thrombin-activated platelets from moderate AD patients.
- APP processing and secretion were analyzed using Western blotting.
Main Results:
- Platelets from moderate AD patients did not show thrombin-induced hyperacidification.
- Moderate AD patients' platelets did not exhibit APP retention on their surface.
- APP processing and secretion were found to be normal in moderate AD patients.
Conclusions:
- The aberrant platelet signal transduction and APP processing defects observed in advanced AD do not appear in moderate AD.
- These specific platelet abnormalities are likely indicative of advanced stages of Alzheimer's disease.