Can Cannabis Save us from COVID?

Worldwide, cases of COVID-19 caused by the SARS-CoV2 zoonotic coronavirus have now surpassed 10.5 million, with over 512,000 confirmed deaths.  U.S. deaths continue to outnumber those of other countries, with 2,636,856 confirmed cases and 127,427 deaths (https://coronavirus.jhu.edu/map.html) as of the writing of this post.  COVID-19 is now considered the greatest global threat the world has faced since World War II, prompting scientists around the world to identify effective treatments and vaccines to slow the pandemic and to lessen its life threatening effects. 

 Reports are surfacing suggesting cannabis as a treatment for COVID-19, such as a recent headline in the New York Post stating, “Scientists believe cannabis could help prevent and treat coronavirus” (https://nypost.com/2020/05/21/scientists-believe-cannabis-could-help-prevent-treat-coronavirus/).  The Post referred to a non-peer reviewed Canadian study where investigators tested hemp extracts to determine their effects on angiotensin-converting enzyme II (ACE2) gene expression and protein levels in artificial human tissues.  ACE2 is the cell receptor of SARS-CoV2 and the main route for the virus to infect human cells.  Since ACE2 plays a crucial role in viral entry into cells, ACE2 expressing cells (such as those found in the oral cavity, lung, intestines and other tissues) serve as critical viral gateways to infection. Some researchers believe that reducing ACE2 expression on cells may be a way to prevent infection.

While the Canadian study found that certain hemp extracts significantly reduced ACE2 levels in some tissues, these findings are very preliminary and a lot more work needs to be done to determine whether a reduction of ACE2 is even a viable treatment for COVID-19.  If so, then clinical trials need to be conducted to determine the utility of hemp CBD in such a strategy. 

The driving force in many gravely ill patients’ downhill battle with COVID-19 is an overreaction of the immune system known as a “cytokine storm,” which other viral infections are known to trigger. Cytokines are chemical signaling molecules that guide healthy immune responses, but when levels of certain pro-inflammatory cytokines soar far beyond what’s needed, immune cells start to attack healthy tissues. Blood vessels leak, blood pressure drops, clots form, and organ failure develops.

Several strategies are being sought to treat the cytokine storm. It’s interesting to note that CBD and THC can suppress lymphocyte proliferation and inflammatory cytokine production in animals and humans.  Therefore, to down-regulate the cytokine storm, it’s plausible that CBD- and THC-based therapeutic strategies could be part of a treatment regimen, along with non-steroidal anti-inflammatory drugs and other medications that target immune pathways.  Again, clinical studies will be needed to better understand whether cannabis and cannabinoid-based medicines have utility as adjuvants along with other discovered treatments to attenuate COVID-related inflammation. If so, it’s likely that the therapeutic dose will far exceed any doses that we’d get by consuming cannabis recreationally.