Fresh blood and old Alzheimer's
A research team led by Claudio Soto from the Health Science Center at the University of Texas at Houston conducted a series of experiments on the exchange transfusion of whole blood to mouse models of Alzheimer's disease and showed that the procedure effectively reduces the accumulation of amyloid plaques in the brain.
The study provided evidence of the concept of using blood "purification" technologies (plasmapheresis, hemodialysis), already used in medical practice, to reduce the accumulation of toxic substances in the brain. This means that, perhaps, the target for Alzheimer's disease therapy may exist in the peripheral blood circulation, and not in the brain.
Alzheimer's disease is the main form of dementia in the elderly. Characteristic pathological changes are the death of neurons, synaptic disorders, chronic inflammation of the brain and the presence of protein aggregates in the brain in the form of amyloid plaques and neurofibrillary tangles. Convincing evidence suggests that improper coagulation, aggregation and deposition of beta-amyloid in the brain play a central role in the development of the disease. Thus, the removal of improperly folded protein aggregates is considered a promising strategy for the treatment of Alzheimer's disease.
However, there is a serious problem of delivering therapeutic agents to the brain through the blood-brain barrier. A new study shows that manipulating the components circulating in the blood in Alzheimer's disease can be an effective solution.
After repeated blood transfusions of a transgenic mouse model from wild-type mice with the same genetic background, the researchers found that the development of amyloid plaques in the brain of Alzheimer's disease was reduced by 40-80%. This led to an improvement in spatial memory in older mice and a decrease in the growth rate of plaques over time.
The exact mechanism by which exchange transfusion reduces the pathological accumulation of amyloid and improves memory is currently unknown. Measurements of plasma beta-amyloid levels shortly after blood exchange suggest that the redistribution of proteins from the brain to the blood may be involved. Another theory is that blood exchange somehow prevents beta-amyloid from entering the brain or inhibits its reabsorption.
But regardless of the mechanisms of action, the study proves that the target for Alzheimer's disease therapy may not be in the brain, but on the periphery.
Article by Urayama et al. Preventive and therapeutic reduction of amyloid deposition and behavioral impediments in a model of Alzheimer's disease by whole blood exchange is published in the journal Molecular Psychiatry.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of UTHealth Houston: Whole blood exchange could offer disease-modifying therapy for Alzheimer's disease, study finds.