Movement disorders, muscle stiffness and tremors: These are the typical symptoms of Parkinson's. There is currently no early detection of this widespread disease. Researchers at the University of Kiel now want to change that.
Parkinson's is the second most common neurodegenerative disease in Germany after Alzheimer's - and the trend is rising. However, it can only be diagnosed when the typical symptoms such as movement disorders, muscle stiffness or the typical shaking, called tremor, occur. Parkinson's is dormant in the body long before the symptoms begin. These could possibly be prevented or delayed if doctors could detect the disease early enough. Researchers at Kiel University now want to make this possible with a blood test.
So far, there have been neither blood parameters nor imaging studies for a reliable diagnosis before the onset of symptoms, let alone for early detection. "This is a dilemma. Because of course you want to discover the disease in the early stages and develop measures to prevent patients from becoming stiff, shaking and slowing down," says study author Annika Kluge.
In the search for reliable, clinically applicable biomarkers for the chronically progressive brain disease, Kluge and her research team say they have made a breakthrough. The scientists have developed a blood-based biochemical test for the diagnosis of Parkinson's for the first time. This is very precise, says Kluge, who works as an assistant doctor at the UKSH Clinic for Neurology. "With the help of our method, the tested 30 Parkinson's patients could be distinguished from the 50 controls with a very high sensitivity." The research team published the results in the specialist journal "Brain".
The new method is based on three steps: First, vesicles from the nervous system have to be isolated from an ordinary blood sample and obtained, explains study author Kluge. Vesicles are small bubbles that are pinched off by cells and contain proteins from the original cell. "That means I can look inside the brain when I'm examining these vesicles," she adds.
In a second step, a targeted search is then made in these isolated nerve cell vesicles for the protein that causes Parkinson's disease. According to Kluge, it is an altered form of a specific protein and can be detected using antibodies that specifically match this form. The last and most important step involves multiplying the disease-causing proteins.
"This has already been achieved with other tissue samples, but never before with vesicles obtained from the blood of patients," says the scientist. It is the accumulation of pathologically altered proteins that leads to the destruction of the affected nerve cells and thus causes Parkinson's disease. If this accumulation can be detected, it is confirmation that the corresponding disease-causing proteins are present in a sample.
"The results are really sensational," says co-author Daniela Berg. On this basis, a blood test for the diagnosis of Parkinson's disease could be developed. However, the method still needs to be further developed so that it can be widely used. It is also still unclear whether the test will also work in Parkinson's-like diseases.