Two molecules found in different plants, including birch extracted, could prevent viruses as formidable as HIV, Ebola and dengue fever from infecting the organism, demonstrate work carried out in Quebec.
This could one day lead to the development of wide spectrum antiviral prophylactic treatments that would be administered to populations at risk of being infected.
“These molecules are attached to a receptor on the cells of the immune system and will block the HIV entry route, but it is an entry route which is also used by the EBOLA virus, the Sras-COV-2 and by the dengue virus, summed up Professor Charles Gauthier, of the National Institute of Scientific Research (INRS). It is really a main receiver. »»
Professor Gauthier and his colleagues were interested in betulinic acid, which is found in particular in birch bark and in the Chaga mushroom, and echinocystic acid, which was found in sunflowers and other plants.
Scientists used a unique methodology to modify these molecules by adding a sugar, Lewis X, which gave birth to new chimerical compounds which had never been described in the scientific literature, “saponins”.
These compounds have several advantages compared to original molecules, in particular to be much more soluble in water; to dissolve relatively easily in organic environments; And, which is far from trivial, to be safe for human cells.
“Our results suggest that these saponins are promising to prevent the first stages of HIV-1 infection while being relatively non-toxic in vivo,” write the authors.
Another interesting property of saponins lies in their ability to spontaneously form structures called “micelles” or to integrate into structures – liposomes – which transport substances through the body. This could allow, in future work, to further improve their effectiveness against HIV, in particular by facilitating their targeting towards the cells affected by the virus.
In addition, add researchers, as saponins interfere with a path that several infectious agents, and not only HIV, use to infiltrate human cells, they are currently studying the inhibitory activity of saponins […] Against other pathogens ”, such as Ebola hemorrhagic fever, dengue fever and even the Sars-Cov-2.
The antiviral properties of betulinic acid have been known for a long time, but its use was limited by the fact that the molecule is essentially impossible to dissolve in water, which makes its administration difficult in medicine.
The work of Professor Gauthier and his colleagues could make it possible to overcome this obstacle. And since we find cethery acid in large quantities in the birch bark, we could consider a new valuation of this current residue of the forest industry.
“We do not know what to do with these bark,” said Professor Gauthier, who is also a member of the mixed inrs-Uqac research unit in sustainable health. We make panels, we burn them … So, we could use bark residues, isolate these molecules, add the Lewis sugar […] And generate these molecules which could prevent the appearance of the AIDS virus. »»
These works may only represent the tip of the iceberg, added Professor Gauthier, since there are reasons to believe that the addition of Lewis X type sugar to other molecules found in nature could lead to the development of even more products with interesting properties, such as vaccine adjuvants.
All this highlights the unimaginable wealth of nature that surrounds us and proves that it still contains surprises with revolutionary potential.
“We work for example on fruit (from the Quebec forest) which have never been studied,” said Professor Gauthier. We study this and we come across molecules that could revolutionize antibiotic treatments […] But that will be for a next publication. »»
The conclusions of this work was published by the scientific journal Chemistry – A European Journal And will be presented shortly as part of a scientific congress in Poland.
