Coronavirus can attack 21 different regions of the brain
ACE2 receptor activity was also detected in the eye, suggesting the visual system may provide an additional entry point for SARS-CoV-2
According to a new study on the gateway receptor of the Covid-19, a wide variety of symptoms and organs may be involved with the SARS-CoV-2 infection. The findings were published in the journal Cellular and Molecular Neurobiology.
The study led by Walter Lukiw, PhD, Professor of Neuroscience, Neurology, and Ophthalmology at LSU Health New Orleans’ Neuroscience Centre of Excellence and School of Medicine, suggested that a multi-organ infection with SARS-CoV-2 may be via the angiotensin-converting enzyme 2 (ACE2) receptor, which is found almost everywhere throughout the body.
For the study, the team of researchers examined 85 human tissues for the presence of ACE2 receptors.
ACE2 is a protein that is found on the surface of many immune and non-immune cell types. ACE2 is an enzyme and an active part of the system that regulates blood pressure, fluid, and electrolyte balance.
In the case of the coronavirus infection, ACE2 receptors act like locks on cells, and the SARS-CoV-2 spike proteins act like keys that open the locks letting the virus enter cells to rapidly multiply. It also controls tissues in the lungs, digestive, renal-excretory, reproductive, eye tissues, and 21 different regions of the brain, the study noted.
Besides strong ACE2 expression in respiratory, digestive, renal-excretory, and reproductive cells, high ACE2 expression was also found in the amygdala, cerebral cortex, and brainstem.
The study speculated that the infection may lead to cognitive deficits associated with SARS-CoV-2.
Some of the highest ACE2 expression levels were found in the pons and medulla oblongata in the human brainstem, an anatomical region of the brain containing the medullary respiratory centres, and this may, in part, explain the susceptibility of many Covid-19 patients to severe respiratory distress.
The team further noted that ACE2 receptor activity was also easily detected in the eye, suggesting that the visual system may provide an additional entry point for the SARS-CoV-2 invasion.
The study revealed that eyeglasses or face shields may be as important as face masks in reducing SARS-CoV-2 transmission and infection.
Dr Lukiw said in a statement: “Several important research gaps remain. A real danger of SARS-CoV-2 infection is not only its highly transmissible and contagious nature and lethality, but also its simultaneous and multipronged attack on many human cell and tissue types involving vital and critical respiratory, immunological, vascular, renal-excretory and neural systems as well as an unprecedented coordinated disruption of the complex neurophysiology, neurochemistry, neurobiology and neurology of the cells of the brain and central nervous system (CNS) that normally regulate these multiple physiological systems.”