For the first time, researchers have used human data to quantify the speed of different processes that lead to Alzheimer’s disease and found that it develops in a very different way than previously thought. Their results could have important implications for the development of potential treatments.
Scientists identify the cause of Alzheimer’s progression in the brain
The international team, led by the University of Cambridge, found that instead of starting from a single point in the brain and initiating a chain reaction which leads to the death of brain cells, Alzheimer’s disease reaches different regions of the brain early. How quickly the disease kills cells in these regions, through the production of toxic protein clusters, limits how quickly the disease progresses overall.
The researchers used post-mortem brain samples from Alzheimer’s patients, as well as PET scans from living patients, who ranged from those with mild cognitive impairment to those with late-stage Alzheimer’s disease, to track the aggregation of tau, one of two key proteins implicated in the condition.
In Alzheimer’s disease, tau and another protein called amyloid-beta build up into tangles and plaques – known collectively as aggregates – causing brain cells to die and the brain to shrink. This results in memory loss, personality changes and difficulty carrying out daily functions.
By combining five different datasets and applying them to the same mathematical model, the researchers observed that the mechanism controlling the rate of progression in Alzheimer’s disease is the replication of aggregates in individual regions of the brain, and not the spread of aggregates from one region to another.
The results, reported in the journal Science Advances, open up new ways of understanding the progress of Alzheimer’s and other neurodegenerative diseases, and new ways that future treatments might be developed.
Image: SumaLateral Whole Brain Image
Reproduced courtesy of the University of Cambridge
The University of Cambridge is acknowledged as one of the world's leading higher education and research institutions. The University was instrumental in the formation of the Cambridge Network and its Vice- Chancellor, Professor Stephen Toope, is also the President of the Cambridge Network.