Hope: The breakthrough could pave the way for a treatment routinely taken by middle-aged people to stop dementia in its tracks (file image)

Scientists have discovered the key to stopping Alzheimer’s disease in its earliest stages.

The breakthrough paves the way for a ‘statin-like’ drug that could be taken by millions to prevent dementia.

Cambridge University researchers have found a naturally occurring molecule that can slow the formation of plaques in the brain.

Amyloid plaques are closely associated with declining memory and other Alzheimer’s symptoms.

The discovery raises the prospect of a treatment which could be routinely taken in middle age to stop dementia. It could even result in a pill that could be used to treat dementia in the same way that statins are used to prevent heart disease today.

Lead author Dr Samuel Cohen told the Daily Mail last night: ‘This is the starting point for finding a drug that stops Alzheimer’s disease in its tracks. It might be used when the first symptoms appear. But another potential approach is that people would take it as a preventative drug.’

The condition affects more than 830,000 people in the UK.

The research, published in the journal Nature Structural and Molecular Biology, is the first to reveal how the specific molecule can slow the formation of plaques in the brain. Amyloid plaques are created when fibrils – tiny toxic threads of protein – wrap around nerve cells in the brain and form clumps which scientists believe interfere with brain functions.

The Cambridge researchers, who worked with collaborators in Sweden and Estonia, found that molecules of Brichos – part of a family of proteins that occur naturally in human lungs – can slow the process.

Tests on mice showed that the molecules stick to the fibrils and stop them forming more plaques, halting their spread in the brain. Dr Cohen, of St John’s College, Cambridge, said that the findings open up new avenues for dementia research. The molecules themselves are not suitable for use in pills as they would not survive the digestive process.

Understanding: The research is the first to reveal the way a naturally-occurring molecule can slow the formation of plaques in the brain. These plaques are closely associated with declining memory and other symptoms of Alzheimer’s (a brain ravaged by the disease is pictured)

But Dr Cohen said many similar proteins may be more suited for use as a drug.

‘There may well be lots of other molecules like this – we just have not been looking until now because it was not clear what to look for,’ he said. If a suitable molecule is discovered, it could open the way to a drug that can wipe out the damaging plaques as soon as they start to appear.

This is the starting point for finding a drug that stops Alzheimer’s disease in its tracks Lead study author Dr Samuel Cohen

Dr Cohen said: ‘People could take them in their 60s to stop these proteins grouping together, well before the symptoms appear, which would reduce the risk of developing the devastating effects of this disease.’

The study was welcomed last night by health charities who said it promised to reduce the ‘catastrophic effect’ of dementia.

Dr Laura Phipps of Alzheimer’s Research UK said: ‘This study has revealed clues to how to block one important chain of events in the disease.’

Dr Doug Brown of the Alzheimer’s Society added: ‘This revelation is exciting as it gives scientists a whole new way of looking at the problem, opening the doors to possible new treatments.’