Flashing lights could halt the advance of Alzheimer’s

‘Exciting’ breakthrough helps brain fight plaques

FLASHING lights in the eyes of Alzheimer’s sufferers could be a new weapon in the battle against the disease, a study suggests.

In an ‘extremely exciting’ new avenue of research, flickering lights were found to drastically reduce levels of plaques in the brain in mice with Alzheimer’s symptoms.

In Alzheimer’s disease, pieces of protein build up to form plaques which can cause the brain cells beneath to become inactive, stopping the brain’s normal function and blocking signals.

But the light treatment was found to encourage cells to begin firing normally again. As the normal pattern was resumed, this boosted the natural immune response of the brain.

‘Scavenger cells’ – called microglia – were activated in the brain and began to eat the plaques. Researchers exposed mice to the flashing lights for one hour a day for seven days and discovered dramatic results. The amount of amyloid plaques had been reduced by up to 60 per cent.

The research raises the prospect of a drug-free alternative to tackling Alzheimer’s.

Lead scientist Professor Li-Huei Tsai, of the Massachusetts Institute of Technology (MIT), said: ‘It’s a big “if”, because so many things have been shown to work in mice, only to fail in humans.

‘But if humans behave similarly to mice in response to this treatment, I would say the potential is just enormous, because it’s so noninvasive, and it’s so accessible.’

Michael Sipser, dean of MIT’s School of Science, said the results ‘may herald a breakthrough’ in the understanding and treatment of Alzheimer’s. He added: ‘Our scientists have opened the door to an entirely new direction of research on this brain disorder. I find it extremely exciting.’

The researchers told the journal Nature that in a healthy brain, cells fired in a synchronised way, between 25 to 80 times a second.

This pattern – ‘gamma oscillation’ – is less likely to be seen in Alzheimer’s patients, but it is thought to be essential for normal brain functions such as attention, perception and memory. By flickering LED lights at 40 hertz – 40 times a second – brain cells in the mice began to fire in an organised way again.

An hour of exposure to the flickering lights cleared away half the plaques that had built up in the visual cortex brain regions of mice in the very early stages of Alzheimer’s. But the deposits returned to their original levels within 24 hours.

Repeating the treatment for seven days led to a 60 per cent reduction in plaques in the visual cortex.

Another major result showed that the treatment also curbed the build-up of tau protein ‘tangles’ within brain cells, a second hallmark of Alzheimer’s that may follow on from the accumulation of plaques.

British experts cautioned that any potential treatments for humans were still a long way off.

Dr David Reynolds, chief scientific officer at Alzheimer’s Research UK, said: ‘Researchers will need to explore how light flickering approaches could not only reduce amyloid in the visual area of the brain but in those areas more commonly affected in Alzheimer’s.’

‘The potential is enormous’