Researchers at the University of California, Los Angeles have explained how COVID-19 damages not only the lungs, but other organs as well. Using experiments on mice, the researchers found the cause of severe symptoms, which is that the coronavirus stops the production of metabolic energy in the cells of the heart, kidneys, and spleen. This is reported in an article published in JCI Insight.
Ordinary mice are not susceptible to SARS-CoV-2, because the virus does not recognize the ACE2 protein in them, which in humans interacts with the S-protein, helping the pathogen to enter the cell. Specifically to study the mechanism of infection, scientists bred GM mice, which have a human version of ACE2 in the cells of various organs. When infected with coronavirus, they develop pneumonia, as well as other dangerous disorders.
Within seven days, all COVID-19 mice stopped eating, were completely inactive, and lost an average of about 20 percent of their weight. They showed changes in the level of immune cells, edema of the heart tissue and dysfunctions of the spleen. In addition, the metabolic processes that produce energy (the tricarboxylic acid cycle and the respiratory electron transport chain) were suppressed.
Some changes in all organs of mice with COVID-19 persist for a long time. The virus is capable of causing epigenetic changes, that is, modifications to the structure of DNA that affect the activity of genes.