A sticky protein implicated in Alzheimer's disease disrupts the brain's circuitry by inducing seizures that give barely an outward sign that they're happening, a study of mice shows.
Excessive buildup of a protein called amyloid-beta in the brain is a hallmark of Alzheimer's disease, and scientists have long suspected that this protein plays a deleterious role in the disease.
In the new study, amyloid-beta triggered excessive firing of neurons, leading to subtle seizures in parts of the mouse brain that are central to memory and learning, says study coauthor Lennart Mucke, a neurologist at the Gladstone Institute of Neurological Disease at the University of California, San Francisco. The episodes fall short of causing the jerking motions or convulsions seen in some epileptic seizures, which could explain why their occurrence in mice with an Alzheimer's-like condition had gone largely unnoticed. The findings appear in the Sept. 6 Neuron.