Every day more sequelae and affectations of the Covid-19, recently a group of scientists from the National Institute of Medical Research in France, determined that SARS-CoV-2 causes the death important cells of the cerebral vascular system.
As part of an international collaboration, Inserm researchers identify for the first time a direct effect of SARS-CoV-2 on blood vessels in the brain. Certain cells, the cerebral vascular endothelial cells, essential components of the blood-brain barrier that protect the brain, are affected by a phenomenon of cell death. These results were published in the journal Nature Neuroscience,
Blood vessels are made up of endothelial cells. Among them are the vascular endothelial cells of the brain that form the blood-brain barrier (BBB). The main function of the BBB is to isolate the central nervous system from the bloodstream, preventing foreign substances or potentially toxic molecules from entering the brain and spinal cord.
By participating in this effort, the vascular endothelial cells of the brain They therefore play a fundamental role in the good supply of blood to the brain and their survival is essential for their proper functioning.
Thanks to preclinical study models, but also by studying the cortex of patients who died as a result of infection by Covid-19, the researchers concluded that the infection would lead to death of the cells endothelial brain, which would give rise to the appearance of “ghost vessels” (that is, empty tubes, without endothelial cells).
How does this cell death occur?
The team discovered that SARS-CoV-2 causes the endothelial cells it infects to produce molecular scissors from their own genetic material. These scissors will cut a protein called NEMO, essential for the survival of endothelial cells, which will therefore die.
The consequences of cell death
According to scientists, cell death vascular endothelial brain It can have two important consequences:
- A temporary breakdown of the blood brain barrier that causes microbleeds in areas where blood is not supposed to be able to freely access.
- Hypoperfusion of certain regions of the brain (due to the presence of non-functional phantom vessels), that is, a decrease in blood flow that can lead to death of patients in the most severe cases.