Past studies have suggested that blueberries may help reduce our risk of diabetes and heart attack. Now, researchers from Memorial University of Newfoundland in Canada suggest the fruit could help treat Parkinson's disease and other neurodegenerative disorders.
Approximately 500,000 people in the US have Parkinson's disease, and there are 50,000 new cases of the condition diagnosed every year. Exactly what causes the disease is unclear, but past research has indicated that a protein called alpha-synuclein may play a role in its development.
Alpha-synuclein is a protein in the brain that is primarily found at the end of nerve cells that reside in nervous system structures, called presynaptic terminals. These terminals are responsible for releasing neurotransmitters - chemical messengers that send signals between neurons that are crucial for normal brain function.
According to the Memorial University investigators, studies have suggested that alpha-synuclein plays a critical role in regulating the release of dopamine - a neurotransmitter involved in motor control that is believed to be lacking in patients with Parkinson's.
"This gene is proven to be the cause of inherited Parkinson's disease in human families that have more of the gene, or an unusual form of it," explains study co-author Dr. Brian Staveley, of the Department of Biology at Memorial.
Furthermore, the researchers say studies have shown that individuals who have an accumulation of alpha-synuclein are more likely to experience oxidative stress. This is an imbalance between the production of free radicals - molecules that can cause cell damage or death - and the body's ability to protect from cell damage with antioxidants.
Blueberry extract increased lifespan and improved defects in fruit fly models
To study alpha-synuclein further, the researchers put the protein in fruit flies. They found that it caused the flies to experience a series of defects, including retinal degeneration and reduced lifespan.
The team then wanted to see whether blueberry extract would improve these defects in the flies. Blueberries are known to be rich in fiber, antioxidants and phytonutrients. They compared the effects with those of a standard control diet.
In fruit fly models that had a protein linked to Parkinson's, blueberry extract increased lifespan and improved eye defects.
The researchers found that flies that were fed the blueberry extract had up to an 8-day (15%) greater lifespan than flies that had been fed a standard diet. In addition, blueberry extract appeared to improve eye defects in the flies.
According to Dr. Staveley, the increase in lifespan seen in the fruit flies is the equivalent to an 8-year extended lifespan in humans. "If you have a disease and you're given an extra 8 years of life, you'd probably be pretty happy with that," he adds.
Dr. Staveley says that compared with pharmaceuticals, nutraceuticals - food products that provide potential medical and health benefits - do not receive enough medical testing as they do not need it for approval.
"So, what you get instead is: 'Eat this. It's good for you,'" he adds. "That's great, but by approaching it from a scientific perspective, we hope to be able to see exactly what a particular extract can do in fly models."
As such, he plans to start working with Sedna Nutra - a producer of powders from wild berries - to evaluate their blueberry and cranberry supplemental extracts.