Early signs of Alzheimer’s have been discovered together for the first time, paving the way for better diagnosis of the disease, Scottish scientists say.
Using human brain samples, Aberdeen University experts found that two molecules believed to contribute to the disease are both present at very early stages of Alzheimer’s in an area of the brain involved in making memories.
Scientists previously thought that tau and amyloid proteins developed in separate parts of the brain, but these findings show for the first time that they might be connected.
Author Professor Bettina Platt said the study solves “a long-standing puzzle” on how to detect these early changes in the brain, which lead to Alzheimer’s.
Professor Bettina Platt said: “It has long been assumed that Alzheimer’s-related changes within the brain occur long before symptoms are evident, but so far reliable methods to detect these were elusive.
“However, we have managed to modify experimental procedures in a way that we can now very sensitively determine when and where these proteins appear, and the big surprise was that they both appear together very early on, and in the same brain area.
“In doing so we have established a new benchmark for pathological investigations.
“Therefore, a long-standing puzzle in the field of dementia research has now been resolved to a large extent.”
It is hoped the research could pave the way for new drugs and improve diagnosis.
Dr Rosa Sancho, head of research at Alzheimer’s Research UK, said: “These proteins have long-puzzled scientists, as although we know that amyloid and tau make up the plaques and tangles found in the brains of people with Alzheimer’s, these build-ups don’t always correlate well with damage occurring to nerve cells.
“This study shows that specific forms of tau and amyloid appear early in the disease process in the same brain region, before plaques and tangles are formed.
“Understanding which forms of tau and amyloid drive the early stages of Alzheimer’s will allow scientists to design drugs to target these specific forms and find new ways to accurately diagnose people.”