ALZHEIMER’S SCIENTISTS CLOSE IN ON DRUG-FREE TREATMENT

FLICKERING light in the eyes could form the basis of a new Alzheimer’s treatment with the potential to halt or even reverse the disease, research has shown.

Results from experiments in the US show a close link between brain waves and a clinical hallmark of the condition.

Scientists using flashing light to synchronise firing of neurons at a specific frequency were able to cut levels of a toxic protein linked to Alzheimer’s in mice.

Sticky plaques of beta-amyloid peptide are believed to be at the root of the condition, triggering effects that lead to the progressive destruction of brain cells.

At 40 cycles per second, the electrical waves not only reduced beta-amyloid formation but also boosted immune cells to clear the harmful material from the brain.

Potential

No drug yet exists that can halt or slow the progress of Alzheimer’s, and last month saw the failure of new immunotherapy drug solanezumab in a Phase III trial.

The US study raises the prospect of a drug-free treatment.

Lead scientist Professor LiHuei Tsai, of the Picower Institute for Learning and Memory at the Massachusetts Institute of Technology, said: “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 non-invasive and accessible.”

Michael Sipser, dean of MIT’s School of Science, said the results “opened the door to an entirely new direction of research”.

For the flickering light studies, published in the journal Nature, scientists put together a simple device consisting of a strip of LEDs that could be programmed to flash at different frequencies. An hour of exposure to light flickering at 40 hertz (40 times per second) cleared away 50 per cent of the beta-amyloid in the visual cortex of mice in the very early stages of Alzheimer’s.

The deposits returned within 24 hours but repeating the treatment for seven days led to a 60 per cent reduction, proving that the effect could be lasting.

Future work will have to find out whether the method could work in other parts of the brain including the hippocampus, the centre for memory which is most affected by Alzheimer’s.

Flickering light produces “gamma oscillations” which boost genes that control microglia cells which mop up beta-amyloid. Previous studies have hinted that Alzheimer’s patients are less likely to display gamma waves, which are thought to aid attention, perception and memory.

Dr David Reynolds of Alzheimer’s Research UK said: “Changing brain cell rhythms could be a future target for therapies.

Explore

“But 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.” And Dr Mark Dallas, lecturer in neuroscience at the University of Reading, said: “As the authors indicate we are some way off using this research as a rationale for new treatments.”