There has been a lot of buzz about cannabis and COVID-19 the last few weeks. Blogs with titles stating, “Cannabis treats Covid-19” and “Cannabis kills Covid” are popping up everywhere. Here’s what is really going on.
In January, a study published in the Journal of Natural Products found that two common cannabis compounds, CBGA and CBDA could prevent the SARS-CoV-2 virus from penetrating isolated human cells in a lab.
Here’s what you should understand about the study, including what the researchers found, its limitations, and what we have yet to learn.
A team of researchers led by Dr. Richard van Breemen, a professor of medicinal chemistry at the Linus Pauling Institute at Oregon State University, were studying a variety of plants in search of natural compounds that could potentially stop the coronavirus from entering cells.
Dr. Bremen wrote, “A member of the Coronaviridae family, SARS-CoV-2 is an enveloped, nonsegmented, positive-sense RNA virus that is characterized by crown-like spikes on the outer surface.” He goes on to say, “ Binding of the viral spike protein of SARS-CoV-2 to the human cell surface receptor angiotensin-converting enzyme-2 (ACE2) is a critical step during the infection of human cells. Therefore, cell entry inhibitors could be used to prevent SARS-CoV-2 infection as well as to shorten the course of COVID-19 infections by preventing virus particles from infecting human cells.”
In an interview with Vice, Dr. Breemen stated the team was looking to answer, “Could small molecules from nature, like from plants, have the same ability to stop the virus from infecting a cell if they had an ability to bind to the surface of the virus and specifically to the spike protein of the virus, which is what’s making contact with the human cell and enabling it to infect the cell?”
The team studied black cohosh, red clover, licorice, and hemp. While looking at hemp, they found three different acids had a strong affinity for binding to the spike protein: cannabidiolic acid (CBD-A), cannabigerolic acid (CBG-A), and tetrahydrocannabinolic acid (THC-A). Other cannabinoids showed only weak or no binding ability.
Although THCA was included in the study, hemp contains very low amounts of THCA and because it is still listed as a controlled substance, testing was limited, and the research team was not able to test it the way they needed to.
Moving forward with CBDA and CBGA, the team incubated live SARS-CoV-2 with each of the cannabis compounds as well as a control compound. Then, they exposed human cells to the cannabinoid-virus mixture. After 24 hours, they found no evidence of the virus getting inside the human cells. Breemen writes that these results “clearly indicate that CBDA and CBG are both able to block cell entry by SARS-CoV-2.” Breemen goes on to say, “CBDA and CBGA are produced by the hemp plant as precursors to CBD and CBG, which are familiar to many consumers. However, they are different from the acids and are not contained in hemp products.” He continues with, “The active compounds we’ve discovered in hemp are cannabidiolic acid, CBD-A, CBG-A, and THC-A,” The ‘A’ stands for an acid group, a carboxylic acid — this group can be removed upon treatment. So, if these hemp products containing these compounds are smoked or vaped, the heat exposure could cause the chemical decomposition or conversion of CBD-A to CBD, CBG-A to CBG, and THC-A to THC. We know that CBD, CBG, and THC are not active against the virus. So, we would recommend in favor of an oral administration of these compounds instead of smoking them or inhaling them from vaping.”
Although this recent research is exciting and shows the potential power of cannabis in the fight against COVID-19, follow-up studies are needed. Results from a lab petri dish are far off from animal or even human results. So, until further testing can be done, we cannot say whether CBDA or CBGA will actually help prevent the SARS-CoV-2 virus or not.
van Breemen, R. B., Muchiri, R. N., Bates, T. A., Weinstein, J. B., Leier, H. C., Farley, S., & Tafesse, F. G. (2022). Cannabinoids Block Cellular Entry of SARS-CoV-2 and the Emerging Variants. Journal of natural products, 85(1), 176–184. https://doi.org/10.1021/acs.jnatprod.1c00946