Montreal Clinical Research Institute

Doctor Michel Chrétien and his colleague, Professor Majambu Mbikay, also from the IRCM, wanted to know why the antiviral activity of an already known molecule seemed to vary from one time to the next.

“It was like finding a needle in a bale of hay,” said Dr. Chrétien, who recently celebrated his 90th birthday.^e birthday and who discussed his work first with The Canadian Press.

This discovery stems from work carried out over the years on isoquercetin, a flavonoid present in several plants and which exhibited marked antiviral activity in the laboratory. However, some isoquercetin extracts seemed significantly more effective than others.

In collaboration with Canadian and American experts, the Montreal team determined that this antiviral activity did not come from isoquercetin itself, but rather from two previously unknown triterpenoid compounds, present at only 0.4% in the extract analyzed.

These new molecules, called dicitriosides, have proven to be up to 25 times more active than the initial extract against the Ebola virus and SARS-CoV-2 under experimental conditions.

The challenge now will be to produce sufficient quantities of these molecules to be able to test them on animals, said Dr. Chrétien.

And if ever a new antiviral drug results from this discovery, it will not be too much, he stressed, since the COVID-19 pandemic has clearly illustrated to us how modern medicine can quickly find itself short of resources in the face of a new enemy coming out of nowhere.

“If it were an antibiotic, we could say, wait, there are several new ones on the market,” concluded Dr. Chrétien. But they are viruses, they are dangerous, they hang around our noses and there are no valid medications. This is why the news is biologically more interesting and important. »

The findings of this study were published by the Journal of National Products.