A recent study suggests that cannabis strains high in cannabidiol (CBD) may reduce the expression of a key protein that the SARS-CoV2 virus, which causes COVID-19, uses to enter our cells.
Researchers from the University of Lethbridge, a public college in Alberta Canada, have developed more than 800 cannabis strains and extracts for the purposes of modifying gene expression and other molecular processes. In this particular study, which was published online at preprints.org (without peer review), the researchers looked into whether some of their CBD-dominant strains were able to down-regulate the expression of the SARS-Cov2 entry protein, Angiotensin-converting Enzyme II (ACE-2). The SARS-CoV2 virus binds to ACE-2 on the surface of cells in our lungs, nose, and upper airways. After binding, the virus is able to enter our cells, hijack cellular machinery, and replicate. In a small percentage of individuals, this leads to a complex inflammatory cascade causing severe COVID-19 illness.
To conduct the study, the authors obtained 3D tissue models (made to mimic tissues in our airways) and pre-treated them with cytokines to induce inflammation. After that, they exposed the cells to numerous extracts from different strains. They used RNA sequencing and Western Blotting to analyze the expression of ACE-2 and found that a number of their CBD dominant extracts reduced the expression of the ACE-2 receptor in their tissue models. In the discussion of their article, the authors mention that they applied the extracts directly to the tissue media to model medical delivery such as that obtained via a mouthwash, throat gargle, or inhaler/nebulizer. The authors went on to state that the results should not be extrapolated to cannabis smoking because of the findings that tobacco smoking increases ACE-2 expression and is associated with worse outcomes in COVID-19 illness.
While these findings are certainly exciting and interesting they are only preliminary and were published online without peer-review. The research definitely supports further investigating the role that cannabis and CBD have in modifying ACE-2 expression and the implications this has on COVID-19.