Researchers from the University of Southern California, Los Angeles have identified a new blood biomarker that could enable a diagnostic test for the early identification of cognitive decline, the main symptom of dementia and Alzheimer’s disease.
During the research, the team examined the markers related to the blood-brain barrier, which regulates the movement of cells and molecules between the blood and the fluid that surrounds the brain nerve cells.
In more than 160 people with and without cognitive impairment, the researchers measured the levels of a protein called platelet-derived growth factor receptor beta (PDGFRβ) found in capillaries associated with the blood-brain barrier.
The soluble form of the protein is known to be elevated in cerebrospinal fluid when the barrier is affected. The integrity of the barrier was also analysed using an MRI-based technique in 73 participants.
It was observed that individuals with cognitive impairment possessed higher soluble PDGFRβ levels and greater breakdown in the blood-brain barrier in some brain regions, compared to those without cognitive impairment.
The researchers said that the findings indicate soluble PDGFRβ measurements and could enable an early diagnostic test to detect cognitive impairment from Alzheimer’s disease and other causes.
The National Institute of Health (NIH)’s National Institute on Aging (NIA) and National Institute of Neurological Disorders and Stroke (NINDS) supported the research.
NIA programme director Suzana Petanceska said: “Because of our ageing population and growing public health concerns, efforts to find a reliable and accurate predictor of cognitive impairment and dementia are very important to researchers and the public. These early results are showing one possible, promising way to quantify risk.”
The team intend to further validate the findings in a second trial with more participants.
Last month, researchers from Washington University School of Medicine in St. Louis, US and the German Center for Neurodegenerative Diseases unveiled a blood test to detect Alzheimer’s disease even before symptoms appear.
This test is designed to identify blood levels of neurofilament light chain, a structural protein that leaks into the cerebrospinal fluid when brain neurons are damaged or dying.