One of the most important steps towards treating neurodegenerative diseases such as Alzheimer’s is early diagnosis. However, it can also be one of the most challenging. A new review article from researchers at the University of Southern California (USC) has proposed a solution. The team suggests that leaks in the blood-brain barrier could be a suitable warning sign that reveals the early onset of a number of illnesses, including Parkinson’s disease and multiple sclerosis, well before visible symptoms appear. This was published in the journal Nature Neuroscience
Most experts agree that the key to fighting such diseases is to catch it before symptoms appear. Unfortunately, we do not have a reliable or effective way of doing so. In the quest to find a reliable diagnostic method everything from blood and eye tests to PET scans are being looked into in order to catch it early.
This work from scientists at USC is now suggesting a breakdown in the blood-brain barrier could be an early sign of a number of neurodegenerative diseases. This refers to the membrane that prevents harmful particles from making their way into the brain. When this becomes dysfunctional it could potentially allow harmful proteins to move from another part of the body where it is harmless and enter the brain. This could contribute to plaques that are thought to be a fundamental step towards cognitive decline.
“Cognitive impairment, and accumulation in the brain of the abnormal proteins amyloid and tau, are what we currently rely upon to diagnose Alzheimer’s disease,” says Berislav Zlokovic, one of the article’s authors, “but blood-brain barrier breakdown and cerebral blood flow changes can be seen much earlier.”
This, the article suggests, could be an early sign of the progression of a number of illnesses. These include Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and multiple sclerosis. It has also been suggested that simply testing for leaks in the blood-brain barrier could be an even earlier biomarker for some of these conditions.
The downside is that tests for blood-brain barrier dysfunction are not easily accessible. Even identifying signs of leakage requires complex MRI or PET scans. So while this by itself may not be particularly useful for diagnosis, it may help researchers identify better early-stage subjects for medical trials to test new drugs hoping to slow down or even stop the onset of these diseases.