Dementia after a stroke
A group of researchers from the University of Arizona College of Medicine described the effect of brain tissue liquefied after a stroke on healthy brain cells, which can lead to the development of dementia.
According to statistics, about a third of stroke patients develop dementia of unclear etiology.
Stroke leads to the death of brain tissue due to the development of colliquation necrosis. The damaged tissue eventually turns from an elastic dense form into a toxic liquid for the brain. As part of the protective reaction, a glial scar is formed – a dense tissue surrounding the injury zone. The authors suggested that the necrotic fluid slowly sweats into healthy tissue over time and damages it.
The researchers conducted experiments on mouse models of stroke. They took a liquefied damaged area of the brain and placed it in a Petri dish with healthy neurons. After four hours, more than half of the neurons died in comparison with the control cup (cerebrospinal fluid from healthy mice was added to the cells). Atrophy or cytotoxic edema developed in the dead neurons.
In another experiment, the barrier function of the glial scar was evaluated. A dye was added to the necrotic fluid of the mice's brain, and then its spread was observed using a microscope.
The glial scar quite reliably protected healthy tissues from toxic fluid from the stroke zone. Nevertheless, there was a leak: seven weeks after the stroke, the dye was found in intact parts of the brain.
Previously, it was believed that the scar forming around the necrosis zone does not allow toxic components to enter healthy tissues. The results of this study provide food for thought regarding dementia as a long-term consequence of stroke.
It is too early to draw far-reaching conclusions, more than one study needs to be organized and conducted to confirm the data. If the theory is confirmed, then new prospects for treating the consequences of stroke will open up, based on strengthening the barrier function of the glial scar.
Article by J. C. Zbesko et al. Glial scars are permeable to the neurotoxic environment of chronic stroke infarcts published in the journal Neurobiology of Disease.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of The University of Arizona: UA Study: Brain Liquefaction After Stroke is Toxic to Surviving Brain.