COVID-19 shelter? The study found that SARS-CoV-2 attacks the brain and can cause serious illness

Winter has come, the Spring Festival wants to come.
With the increase in the flow of people, the new coronary pneumonia (COVID-19) outbreak caused by the new coronavirus (SARS-CoV-2) infection appears to have become more serious, with official COVID-19 outbreak figures released every day affecting everyone's hearts! With the joint efforts of researchers around the world, we have gained a deeper understanding of SARS-CoV-2, but little is known about the pathogenesis of its central nervous system (CNS).
is well known that the brain is the central processor of human beings, and COVID-19 can cause diseases of the human nervous system, and exploring its pathology can help people better respond to outbreaks and fight disease.
recently, Viruses published an article entitled Neuroinvasion and Enitis Followingitis Intranasal Inoculation of SARS-CoV-2 in K18-hACE2 Mice, which found that SARS-CoV-2 infections in mice with K18-hACE2 in their noses can cause serious neurological diseases.
the path of the nasal passage to the brain is more direct than the mouth, and changes in smell and taste are one of the symptoms of COVID-19, so the researchers inoculated in the nasal cavity of K18-hACE2 mice (n-10) MICE-CoV-2 cells and PBS, infected with SARS-CoV-2 mice began to lose weight significantly on the 4th day, accompanied by drowsiness, slow movement, co-relief disorders, breathing difficulties and other complications, the 6th day of all mice died.
suggests that SARS-CoV-2 may infect cells in the nose, eyes and olfactory balls of K18-hACE2 mice, and that the cause of loss of smell caused by certain COVID-19 cases is reasonably explained.
then, based on qRT-PCR, the researchers analyzed viral loads of organs and brains in mice infected with SARS-CoV-2 in the early (day 1), medium (day 3) and late (day 5 and 6).
found that the amount of virus in the lungs and nasal cavity in mice peaked on day 3 and gradually decreased on day 5 and 6, while viruses in the brain were detected on day 3, reached higher levels on day 5, and the highest level of virus titration in the brain was about 1,000 times higher than the highest titration in the lungs, indicating that SARS-CoV-2 has high replication potential in the brain.
because interferon (IFN) has a broad spectrum of antiviral function, can affect cell growth, differentiation, regulation of immune function and other biological activities.
In further experiments, researchers tested mRNA and protein levels of IFN-α in the lungs and brains of mice and found that ifN-α's mRNA and protein levels in the lungs peaked on day 3 and dropped on day 6, while high levels of IFN-α were detected only on the 5th and 6th days after infection in the brain.
interesting is that although viruses have higher levels of replication in the brain, in the ifN-α perspective, the relative levels in the lungs are higher.
infections of the central nervous system are usually accompanied by inflammatory responses, such as the production of cytokines/convergence factors, based on qRT-PCR on IL-6, IL-1 beta, IFN-γ, TNF-α Tests on S, CCL2 and CCL3 showed that mice with SARS-CoV-2 infected cytokines and coercion factors expressed far more in the brain than in the lungs, suggesting that inflammatory responses were more pronounced in the brain in the later stages of infection than in the lungs.
on the sixth day of infection in mice, researchers detected cell-related viral antigens from parts of the brain, including the cortectal, colium and hippocellus.
results of HE staining and immunological analysis of brain slices showed that neurons in mice shrunk and degenerated, bleeding around blood vessels, and white blood cell immersion increased.
findings explain why some COVID-19 patients have improved lung function, but are likely to relapse and die quickly.
because there is no immune response in the brain, it has become the virus's favorite hiding place.
Although COVID-19 rehabilitation patients appear to have fled THE SARS-CoV-2, they may still face health problems including autoimmune diseases, Parkinson's disease, multiple sclerosis, and general cognitive decline.
, the sly SARS-CoV-2 must not be let down.
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