Scientists have pin-pointed a “bio-marker” that spots a protein made when the brain gets inflamed or damaged and increases before the tell-tale plaques develop – the first sign the disease is taking hold.
Experts said the findings could be used to diagnose those patients at high risk of the debilitating disease and used to deliver drugs to areas of the brain getting infected.
Alzheimer’s disease is the most common type of dementia, affecting an estimated 850,000 Britons with numbers expected to increase.
There is no cure but medication can help relieve some of the symptoms and slow down the progression of the disease.
The sooner the condition is spotted the more effective the treatments are.
Co-lead author Professor Dr Aman Mann said: “We wanted to look at the biological changes that were happening in the Alzheimer’s disease brain and be able to identify these changes very early on.
“The majority of the therapies that are being developed right now are targeting the amyloid plaques which are considered to be the hallmarks of the disease.
“But our effort was to find something independent of the plaques because recent literature has shown this diseases starts well before these plaques begin building up.
“So we have now found a way of detecting something in the blood vessels of the brain which is independent of the plaques and can actually precede the plaque formation in these brains.”
Professor Mann said the bio-marker, a peptide, can be used to diagnose patients that are at higher risk of getting Alzheimer’s or already on the path of getting Alzheimer’s.
He said it could also be used to deliver drugs into the area of the brain that’s getting infected.
“If we were to do that early on, this would really increase the benefit that we could give to those patients,” he added.
The discovery by Prof Mann and colleagues at Sanford Burnham Prebys Medical Discovery Institute in La Jolla in California could also help with brain injuries and stroke.
The discovery of the peptide was made using lab mice that are programmed to develop Alzheinmer’s.
In these young mice, the peptide detected the earliest stage of the disease.
Prof Mann said if the early appearance of the peptide holds true in humans, it could be used as a tool to identify patients at early, pre-symptomatic stages of the disease when treatments already available may still be effective.
Senior author Distinguished Professor Dr Erkki Ruoslahti said: “The change in Alzheimer’s disease blood vessels gives us an opportunity to create a diagnostic method that can detect Alzheimer’s disease at the earliest stage possible.
“But first we need to develop an imaging platform for the technology, using MRI or PET scans to differentiate live Alzheimer’s disease mice from normal mice.
“Once that’s done successfully, we can focus on humans.”
The study was published in Nature Communications.