Written by Kranti Kaur

Alzheimer’s disease is a brain disease, a type of dementia, a term that means memory loss severe enough to hinder daily life experiences. The greatest risk factor for Alzheimer’s is aging. Usually those with Alzheimer’s tend to be 65 years of age or older: those who develop the disease prior to reaching 65 years old are considered to be people with early-onset Alzheimer’s. Those suffering from this disease get progressively worse as time goes on. Symptoms start off with mild memory loss and escalate until a conversation cannot be carried on and environmental responses are severely diminished. As of now, there really is no cure, although there is a treatment called Aduhelm that demonstrates that removing amyloid can slow the cognitive decline of the disease. Amyloid proteins and tau tangles are both known to be involved with the disease, which is why they are the target of many therapies and treatments. Other treatments can temporarily slow the progression of the disease and increase quality of life. This is a disease that is truly devastating both for the patient and their family, and it is becoming more important to find a cure. 

In the brains of those with Alzheimer’s disease, there are unnaturally high levels of amyloid proteins. These proteins clump together, which is why they are known as amyloid plaques, and collect between neurons, which in turn, does not allow cells to function normally. For this reason, most treatments target amyloid plaques in the brain. However, a new study suggests targeting the blood. These researchers hypothesized that since amyloid plaque components were found in the blood, if the blood was filtered in some way, the progression of the disease could be slowed. This hypothesis was tested in mice with whole blood exchange treatments to replace blood in those which had amyloid precursor proteins. The results were very optimistic, in that the amount of cerebral amyloid plaques in these mice decreased by 40-80% and the mice showed greater spatial memory and lower plaque growth rates over time.

The technique used in this study was blood dialysis, which is a technique very commonly used in medicine already. This process “cleans” the blood: in this case, it clears the blood of amyloid proteins or precursor proteins. This further serves to decrease the amount of amyloid protein that builds up in the brain, therefore slowing the progression of the disease. It is a huge advantage that this treatment focuses on the blood rather than the brain, since it is so much easier to administer. Since this treatment is already used commonly in medicine, much is already known about it as well. 

There was another research study quite similar to this one that confirmed that hemodialysis reduced amyloid plaque in the brain with PET scan results. This study was a case report on a 77-year-old man suffering from renal failure. In this research article, it was mentioned that not only was hemodialysis, which is blood filtration, effective in reducing amyloid protein buildup in the brain, but that plasma exchange therapy was also effective. This plasma exchange therapy got rid of plasma containing amyloid proteins and administered albumin, which binds to amyloid proteins. This therapy resulted in improved cognitive functions in Alzheimer’s patients. 

The possibility of a treatment much simpler to administer in Alzheimer’s patients than current treatments is quite exciting. It means that there is likely an easier and safer way to treat Alzheimer’s, which would make treatment more accessible while not interfering with the efficacy. Of course, this treatment method needs to be researched more heavily before it can be a widely used technique, but so far the results seem promising. By making treatments for diseases like Alzheimer’s easier to administer, the resulting decrease in cost of care would be very important in terms of increasing the number of patients who can afford treatments.

Edited by Safa Fazili