Power of light used to fight Parkinson’s
The power of light is emerging as a promising way of slowing devastating brain conditions such as Parkinson’s disease.
Clinical trials have been underway in Adelaide and across the country to test whether applying “laser helmets” to the head of patients could improve symptoms and halt disease progression.
A new study from the University of Sydney found applying low-level light to other parts of an animal’s body – particularly the abdomen – could be even more effective at protecting brain cells.
Low level laser therapy, or photobiomodulation, has been used for the past 50 years, typically to treat pain or inflammation. But evidence is emerging of its potential benefit for the brain.
The Sydney team first showed in 2010 that by shining this near infra-red light onto the heads of mice with Parkinson’s disease, it could protect against the loss of brain cells.
“Following that, we’ve done heaps of studies that have used different wavelengths of light, altering when we give the light – either before, during or after the injury – and we consistently show we can protect the brain,” said lead researcher Dr Daniel Johnstone.
“The problem you face moving into humans is that, even at these longer wavelengths we use, you lose about two thirds of your intensity for every millimetre of tissue you pass through. We have thick skulls.”
Dr Johnstone said his team was spurred on by findings in studies around the world that used light to treat wounds and chemotherapy-related mouth ulcers, that could repair tissue not directly irradiated.
After successful studies in mice using this remote light delivery, their most recent proof of concept study in three Parkinson’s disease monkeys, found that delivering light to the head gave no neuroprotection. But delivering it to the lower legs delayed the onset of symptoms, while shining the light on its abdomen prevented the animals from showing symptoms of the disease.
The results were presented at the Australasian Neuroscience Society’s annual scientific meeting this week.
Dr Johnstone said their findings had informed human clinical trials using this remote delivery technique in Adelaide, Brisbane and Sydney and they would now return to mice studies aiming to confirm the findings.
He said there was “pretty good evidence” it worked to make tissue more resilient and better able to deal with injury. PAGE 60: EDITORIAL