Saliva samples detects early signs of Alzheimer’s and Parkinson’s
Researchers at Luleå University of Technology suggest a new strategy to diagnose neurological diseases. By using molecules from the brain that can be measured in saliva, changes that can lead to Alzheimer’s or Parkinson’s disease could be detected up to ten years before symptoms occur. According to the researchers, the method has the potential to make medication more effective before the brain cells begin to break down.
Alzheimer’s and Parkinson’s are two neurodegenerative diseases that lead to the breakdown of brain neurons. Both affect brain function and can lead to cognitive problems such as memory loss, issues with motor skills, difficulty concentrating and impaired communication skills.
The symptoms are similar, but the diseases affect different parts of the brain. While Alzheimer’s affects brain cells in the area controlling memory and learning, Parkinson’s affects neurons that control movement, balance, and coordination. In common for both diseases, however, is the fact that they mainly affect the elderly.
If these diseases could be detected earlier, it could potentially make medication more effective because the molecular degradation processes begin long before symptoms appear.
New screening method proposed
Vaibhav Sharma, postdoctoral researcher in biomedical engineering at Luleå University of Technology, and lead author of a new scientific article in Translational Neurodegeneration, is now proposing a new screening method for early detection of the diseases. The method, which the researchers say has the potential to provide a diagnosis of the diseases up to 10 years before the first symptoms appear, is based on an analysis of a simple saliva sample with molecules derived from the brain.
The research team has shown that Parkinson’s and Alzheimer’s disease can be diagnosed by analysing exosomes in saliva. Exosomes are small nano-sized bubbles secreted from the body’s cells and whose task is to carry information between cells. Other cells recognise the proteins on the outside of the exosomes and in this way the correct recipient is reached. By using the protein on the outside of the exosome, the researchers can discern which exosomes come from brain cells.
Potential for ALS screening
The blood-brain barrier protects brain cells from large molecules being able to enter and exit, but exosomes are so small that they can cross the blood-brain barrier and report on what is going on in the brain. The researchers have now measured the movements of the bubbles with lasers and analysed the amount and size. This makes it possible to determine if there are signs of disease, and to give indications of how far advanced the disease is. The technology is not new, but the application is. They now see potential to develop the method for more neurological diseases, such as ALS.
In a press release, Vaibhav Sharma states: “These diseases severely affect the lives of many people. A saliva sample is a simple method that could lead to early diagnosis. It provides the opportunity to introduce early interventions for the individual that could make a big difference in their life. It also provides an opportunity to understand the disease better which can lead to new treatments.”
Read the article in Translational Neurodegeneration here.
