A study of the blood supply in the hippocampus, a brain region considered to be the “control center” of memories and learning, could provide a possible explanation for one of the early symptoms most typically associated with Alzheimer’s disease, namely loss of memory.
Based on a mouse study conducted by the University of Sussex and published in Nature Communications, even in non-pathological conditions, the blood supply of a part of the neurons of the hippocampus would be barely sufficient to keep the nerve cells alive; thus, when any other factor intervenes that reduces the blood supply to this area, those cells do not receive enough oxygen and die.
On the razor’s edge. A group of scientists from the University of Sussex studied blood circulation and thus oxygenation in the brains of mice, and used simulations to figure out how much blood was getting to the neurons farthest from the blood vessels. From the analysis it emerged that these nerve cells in an unfortunate position normally receive a “right right” amount of oxygen: in short, they live a bit at the limit, and when other factors intervene on the blood circulation, such as those related to the disease, they cease to work.
In this case, the neurons in the hippocampus of mice receive less blood than those in the visual cortex (the brain area that analyzes the shape, location and movement of objects), perhaps because they are less “carried” in contracting to dilate blood vessels.
Errors and memory lapses. This could be one of the possible reasons for the amnesia that lead to suspicion of the onset of Alzheimer’s disease. As Catherine Hall, a neuroscientist among the authors of the study, explains, “the same factors that lead to a risk of heart attack also increase that of developing dementia. In fact, our brain needs enough blood to derive energy – in the form of oxygen and glucose – for the cells to function properly, and also because the bloodstream can remove waste such as beta amyloid proteins that accumulate in the body. Alzheimer’s disease “.
A help in prevention? If these findings also apply to humans, and it is true that increasing the blood supply to the hippocampus reduces memory loss in Alzheimer’s disease, then we could translate our concerns into prevention and increase oxygen-enhancing activities. of the brain, such as physical activity and healthy eating (already associated with a lower risk of developing dementia).
Scientists are also trying to understand whether impaired blood circulation and oxygenation of the hippocampus may also be behind the accumulations of beta-amyloid protein typical of Alzheimer’s disease. In Italy there are about 600,000 people affected by this form of dementia, a number destined to increase due to a disease that involves, in addition to the sick, entire families. The causes of Alzheimer’s disease are still unclear, and the attempts so far spent to find drug treatments have not yielded the desired results.