Patients with Alzheimer’s disease run a high risk of seizures. While the amyloid-beta protein involved in the development and progression of Alzheimer’s seems the most likely cause for this neuronal hyperactivity, how and why this elevated activity takes place hasn’t yet been explained – until now.
A new study by Tel Aviv University researchers, published in Cell Reports, pinpoints the precise molecular mechanism that may trigger an enhancement of neuronal activity in Alzheimer’s patients, which subsequently damages memory and learning functions. The research team, led by Dr. Inna Slutsky of TAU’s Sackler Faculty of Medicine and Sagol School of Neuroscience, discovered that the amyloid precursor protein (APP), in addition to its well-known role in producing amyloid-beta, also constitutes the receptor for amyloid-beta. According to the study, the binding of amyloid-beta to pairs of APP molecules triggers a signalling cascade, which causes elevated neuronal activity.
Elevated activity in the hippocampus—the area of the brain that controls learning and memory—has been observed in patients with mild cognitive impairment and early stages of Alzheimer’s disease. Hyperactive hippocampal neurons, which precede amyloid plaque formation, have also been observed in mouse models with early onset Alzheimer’s disease.”These are truly exciting results,” said Dr. Slutsky. “Our work suggests that APP molecules, like many other known cell surface receptors, may modulate the transfer of information between neurons.”
With the understanding of this mechanism, the potential for restoring memory and protecting the brain is greatly increased.