Researchers from the National Institute for Scientific Research (INRS), the University of Montreal, McGill University and the University of Quebec at Montreal first discovered that tannic acid harms to the connection between the spike protein of the virus and the ACE2 receptors which are on the surface of the cells and which the virus uses to enter inside and start its reproduction.
Even more interestingly, the researchers found that tannic acid interferes with the spike protein of the virus, not the ACE2 receptors, which minimizes the risk of unwanted side effects.
[L’acide tannique] diverts the virus from its biological target
explained to The Canadian Press Professor Charles Ramassamy, of INRS. This is a huge advantage because in fact, it does not disturb, or very little, the functioning of the organism. It will modify the structure of the protein [de spicule]and so it’s as if we were preventing its fixation on the front door.
The results are all the more convincing in that all the researchers who took part in this work came to the same conclusions, even if they used different techniques.
Taking their work a step further, the scientists identified a second mechanism by which tannic acid prevents SARS-CoV-2 from infecting human cells. Finally, they found, lastly, that tannic acid can inhibit the activity of the viral enzyme responsible for the replication of the virus.
« It’s a multi-target mechanism of tannic acid, so to speak, which can act both on the viral protein and on the inhibition of its entry into the cell, or even if the virus is already inside the cell, to prevent its replication. »
The work was carried out in the laboratory on fragments of the virus, and not on the complete virus, for safety reasons. They also focused on the B117 variant (the British variant) which was dominant at the time, and not for example on the Omicron variant, but Professor Ramassamy nevertheless considers that the results are very encouraging.
Tannic acid is a natural polyphenol found in several beverages such as red wine or tea, but in much lower quantities than those used in the study.
You would have to drink a lot of cups of tea or bottles of red wine to get to the concentrations we use
said laughing Professor Ramassamy.
Rather, he is considering the possible development of tablets containing tannic acid or even nasal delivery to prevent or prevent SARS-CoV-2-induced infection.
Such a treatment would be less expensive than antivirals currently on the market, and side effects would be lower due to the low toxicity of polyphenols. Moreover, adds Professor Ramassamy, tannic acid and its physiological derivatives have anti-inflammatory and antioxidant properties, both beneficial during remission from SARS-CoV-2 infection.
The conclusions of this work were recently published in the‘International Journal of Molecular Sciences.
