Alzheimer's memory problems originate with oligomers not plaques

April, 2010

While everyone agrees that amyloid-beta protein is part of the problem, not everyone agrees that amyloid plaques are the cause (or one of them) of Alzheimer’s. A new study provides convincing evidence that floating clumps called oligomers or ADDLs are the real problem.

While everyone agrees that amyloid-beta protein is part of the problem, not everyone agrees that amyloid plaques are the cause (or one of them) of Alzheimer’s. Other forms of amyloid-beta have been pointed to, including floating clumps called oligomers or ADDLs. A new study, using mice engineered to form only these oligomers, and never any plaques, throughout their lives, provides more support for this theory. Mice that never developed plaques were just as impaired by the disease as mice with both plaques and oligomers, and when a gene that converted oligomers into plaques was added to the mice, the mice were no more impaired than they had been before. This may explain why treatments aimed at removing plaques have not been successful, and offers a new approach to the treatment of Alzheimer’s.

http://www.eurekalert.org/pub_releases/2010-04/tmsh-amp042710.php

Reference:

[191] Gandy, S., Simon A. J., Steele J. W., Lublin A. L., Lah J. J., Walker L. C., et al.
(2010). Days-to-criterion as an indicator of toxicity associated with human Alzheimer amyloid-beta oligomers.
Annals of Neurology. 9999(999A), NA - NA.

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