Parkinson’s disease is characterized by progressive neurodegeneration, causing severe impairments in movement. Most often, the disease is associated with uncontrolled tremors; however, patients can also suffer from muscle stiffness and the difficulty moving or speaking. Because the disease is progressive, symptoms worsen over time. There are no cures, but medications can improve some of the symptoms, especially if the disease is diagnosed at early stages.
Though causes of Parkinson’s disease are still undetermined, researchers are working through a number of likely suspects. In particular, Fisher’s team is focused on mitochondrial dysfunction. The mitochondria is the cell’s energy source, and it’s thought that overproduction of a toxic byproduct by this organelle contributes to neuronal breakdown.
“Based on the current literature we were expecting reduced oxygen consumption in the mitochondria, which leads to a build up of toxic byproducts, but what we saw was the exact opposite,” Fisher said. “We were able to show the mitochondria were perfectly normal but were working four times as hard, which also leads to increased production of poisonous byproducts to occur.”
Leveraging this discovery from ten years ago, Fisher and his team developed the blood test based on measuring the production of mitochondria by-products. The presence and abundance of the biomarker will allow the team to predict Parkinson’s disease, in advance of neurological symptoms that may not show up until years later.
In a small trial with 38 participants, including 29 with Parkinson’s disease, they reported the test had high reliability and accuracy. In the next phase, they will scale up the test in 100 people, including 70 with Parkinson’s.
With eyes on the first diagnostic blood test for Parkinson’s, the team is also hopeful that the method can be applied to other neurodegenerative diseases. “It is even possible that the blood test could be developed to detect all types of neuro-degenerative disorders, including Alzheimer's,” said Fisher. “We're hoping to both speed it up and scale it down so that we can use it on very small blood samples in the future,” he added.
It’s important to note that even if the disease is diagnosed earlier, current available treatments can’t slow the progression of Parkinson’s. Even still, patients will undoubtedly benefit from early diagnosis, as prompt treatment may help curb the worsening symptoms over time.
Additional source: The Guardian