UK scientists and Switzerland revealed how coronavirus strikes the human brain, patient COVID-19. The infection does not cause neuron death, but provokes inflammatory reactions that neurological symptoms can be explained. Article of specialists is published in the repository of preprints Biorxiv.
Researchers studied the propagation and influence of the SARS-COV-2 coronavirus in the central nervous system (CNS) of the transgenic mice of K18-HACE2, which expressed the human enzyme ACE2 – protein serving a virus in the cell entering the cell. One group of rodents was infected with low doses of coronavirus, and another was first infected with the influenza virus, and then after three days coronavirus. The third group of animals was used to control. Euthanasia mice was performed on the third day after the dose of SARS-COV-2.
It turned out that the coronavirus penetrated into the central nervous system and was distributed to neurons on the seventh day of infection. At first he struck the olfactory bulb, and then penetrated into the lower areas of the brain and the spinal cord. The infection did not cause the death of nerve cells, axon damage or dimielinization, but the increased activity of immune cells of the nervous system – macrophages and T cells caused moderate inflammation was observed. All this was accompanied by the death of microglia cells and endothelium during apoptosis.
Microglyosis and apoptosis of immune cells indicates that it is microglial cells that can play an important role in the mechanism for the development of neurological disorders with a long COVID-19.
It is known that Coronavirus SARS-COV-2 strikes not only the respiratory system, but also affects the brain, causing such neurological symptoms as loss of smell and taste, headache, fatigue, or more serious complications, for example, cerebrovascular diseases.