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Individual differences in Alzheimer's molecular structure

Submitted by Fiona McPherson on

The first detailed characterization of the molecular structures of amyloid-beta fibrils that develop in the brains of those with Alzheimer's disease suggests that different molecular structures of amyloid-beta fibrils may distinguish the brains of Alzheimer's patients with different clinical histories and degrees of brain damage. A comparison of amyloid-beta fibril fragments from the brain tissue of two patients with different clinical histories and degrees of brain damage found different molecular structures, confirming cell research showing that amyloid-beta fibrils grown in a dish have different molecular structures depending on the specific growth conditions.

Obviously, this is a very small study, and will need to be confirmed across more patients. However, it’s important for indicating that structural variations may correlate with variations in Alzheimer’s, and that structure-specific amyloid imaging agents may need to be used.

http://www.eurekalert.org/pub_releases/2013-09/cp-aps090513.php

Lu, J.-X., Qiang, W., Yau, W.-M., Schwieters, C., Meredith, S., & Tycko, R. (2013). Molecular Structure of β-Amyloid Fibrils in Alzheimer’s Disease Brain Tissue. Cell, 154(6), 1257-1268. Retrieved from http://www.sciencedirect.com/science/article/pii/S0092867413010295 (Original work published 2013)

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