Omega-3 fats could play a vital role in protecting people from motor neurone disease (MND) and a type of dementia, new research suggests.
A study led by the UK Dementia Research Institute and the UCL Institute of Healthy Ageing found the fats – which are found in oily fish, nuts and seeds – affect the conditions and may boost survival.
Previous studies have linked a high consumption of omega-3 fatty acids with a lower risk of developing MND and a longer lifespan for those with the condition.
However, until now, researchers have not understood why this occurs.
In the new research, experts increased the levels of healthy fats in the brain cells of fruit flies carrying a genetic mutation called C9orf72, while also examining human brain cells.
C9orf72 mutation is the most common genetic cause of MND and a rarer form of dementia known as frontotemporal dementia (FTD), which tends to affect younger people.
The team found that, at the start of the study, levels of poly-unsaturated fatty acids, including omega-3 fatty acids, were significantly reduced in the MND/FTD flies.
These fatty acids were also reduced in the brain cells of people with MND/FTD.
Experts specifically looked at alpha linoleic acid (ALA), a type of omega-3 fatty acid found in flaxseed, walnuts and soybean and vegetable oils such as canola oil.
They also looked at linoleic acid, a type of omega-6 fatty acid, found in similar foods.
Scientists fed the flies linoleic acid and alpha linoleic acid to test whether this would impact on their survival.
They found that increasing the amount of fatty acids in their diet led to a small improvement in the survival of the flies.
Next, they delivered the fatty acids directly to the brain cells of the flies which increased the survival of the flies by 83%, from 15 days to 27.5 days.
They repeated the experiment in cells taken from people with MND/FTD and found that increasing levels of the fatty acids in the cells prolonged survival.
The research, published in the journal Nature Neuroscience, was funded by Alzheimer’s Research UK and the UK Dementia Research Institute.
Study leader Professor Adrian Isaacs, from the UK Dementia Research Institute, said: “Epidemiological studies suggest that people with a high intake of omega-3 fatty acids have a lower risk of developing motor neuron disease.
“Our study adds a deeper understanding of the mechanisms behind this.
“From our findings we can conclude that enhancing levels of omega-3 fatty acids in the brain may be beneficial in motor neuron disease. Of course, the next step is to test this in people.
“We first need to work out which specific fatty acid would be best to test in humans, and how we can deliver sufficient quantities to the brain. Then, we want to take these findings forward into a clinical trial.”
The researchers also suggested the findings may also have implications for other neurodegenerative diseases.
Dr Julia Dudley, head of research at Alzheimer’s Research UK, said: “With nearly one million people living with dementia in the UK, there is an urgent need to understand and treat the diseases that cause this condition, including rarer forms.
“Neurodegenerative diseases are complex, however some share similar genetic changes.
“This means that understanding how these changes affect the brain could ultimately lead to new treatment approaches for dementia.
“It is exciting to see findings which suggest that increasing levels of fatty acids, including omega-3 could be protective against motor neuron disease and frontotemporal dementia.
“We are excited to see the next steps for this research which we hope will play a key role in bringing us closer to a cure.”
Last year, MND campaigner and Leeds Rhinos, Great Britain and England rugby league star Rob Burrow died from MND.
His family said they were inundated with messages of support when he died, including a “heartfelt” message from the Prince of Wales.
MND, including its most common subtype amyotrophic lateral sclerosis (ALS), affects around one in 300 people in their lifetime and cannot be cured.