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bioRxiv · 10.1101/760116

Platelet proteolytic machinery assessment in Alzheimer’s Diseases

Muriu, R. G.·Sage, J. M.·Agbas, A.
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Abstract

AimPlatelets provide substantial information about the proteolytic system profile in neurodegenerative diseases. Assessment of autophagy and proteasome target proteins in platelets may reflect tissue proteolytic machinery profile in central nervous system in Alzheimers diseases (AD). We aimed to demonstrate the optimum assay conditions and identify target proteins in platelet proteolytic machinery. MethodsPlatelet samples were obtained from clinically verified AD patients and age-matched non-demented control subjects that were recruited by University of Kansas Alzheimers disease Center. Autophagosome participating proteins in platelets were identified by Western blotting analysis. Standard gel electrophoresis and electro transfer apparatus were used for protein transfer onto the membrane. Several antibodies were tested to identify the best working antibodies, and their concentrations were optimized. An ELISA kit was used for platelet proteasome protein determination. Infrared imaging technology was used for visualizing the proteins on the membrane. ResultsAutophagosome participating proteins showed elevated levels in AD patient platelet cytosol. Only LC3-I autophagosome protein levels were significantly elevated. The concentrations of platelet lysate proteasome were assessed. AD patients proteasome levels were elevated but they were statistically not important as compared to controls. ConclusionsPlatelets can be used for assessing whether proteolytic system is functional. Blood-based sampling from human donors is less-invasive and analyzing platelet proteolytic system profile may help to develop pharmaceutical intervention approaches for neurodegenerative diseases in general.

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Muriu, R. G., Sage, J. M., Agbas, A.. 2019-09-08. Platelet proteolytic machinery assessment in Alzheimer’s Diseases. https://doi.org/10.1101/760116

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