Cannabis is a multipurpose plant that has gained significant interest in the field of antiviral therapies. Cannabidiol (CBD) is the primary non-psychoactive ingredient of Cannabis sativa, which is currently at the spearhead of this scientific feat mainly because of its broad-spectrum biological activity.
Currently, one of the most exciting fields of CBD research is aimed at defining its potential as an agent that can act against broad-spectrum viral infections.
This is especially relevant with the increasing outbreaks of viruses, such as Zika virus and severe acute respiratory syndrome coronavirus 2.
CBD is a potent weapon in the fight against viral infections
Although the antioxidant properties of cannabidiol have been known for some time, the antiviral effect of this compound is yet to be explored.
The Zika virus is an infectious virus transmitted mainly through the bite of Aedes aegypti mosquitoes. It imposes severe health threats because it is associated with neurologic issues like microcephaly and Guillain-Barré syndrome.
Prevalence rates of ZIKV infection are highly increasing; however, till now, there is no specific treatment or vaccine developed.
This lack of medical therapies and preventative agents has accelerated the need to find an alternative to CBD with potent antiviral activity.
Recent research has been done to unravel the mechanisms by which CBD exerts its antiviral activity; it has been identified as effective against a wide range of viruses, including enveloped and non-enveloped viruses.
Cultures infected with various viruses were exposed to noncytotoxic concentrations of CBD, after which quantification of viral titers was conducted.
This study demonstrated that CBD has strong antiviral properties. The effective concentration needed to inhibit the viruses ranged from 0.87 to 8.55 micromoles per liter. This means that CBD was able to combat various viruses effectively within this concentration range.
Mechanism of action.
A significant finding in this investigation was the activity of CBD on the immune response during ZIKV infections. Infected and uninfected Huh-7 cells, treated with ten micromolar CBD for 48 hours, showed a significant increase in interferon beta.
The rise in interferon beta reflects the increase in one of the most significant antiviral immune responses after CBD treatment, thereby enhancing the body’s ability to fight against viral infections.
Quite strikingly, the pro-inflammatory classic interleukins IL-6 and IL-8 are not induced by CBD treatment, suggesting an instead focused immunomodulatory effect than generalized immune activation.
Further studies demonstrated that CBD affected the cellular membranes, as indicated from immunofluorescence by wheat germ agglutinin labeling of cell membranes of higher intensity of fluorescence with CBD treatment.
When this extra data set was analyzed and interpreted about the other changes, it indicated increased intracellular cholesterol. Cholesterol is a significant factor for infection and replication of many viruses, including ZIKV.
More recently, it has been found that CBD impedes viral multiplication by altering cellular membrane lipid composition, a process by which the viruses are precluded from host cell hijacking for their replication.
Broad-Spectrum Efficacy. A Promising Alternative
This specific feature considerably narrows the effectiveness of CBD against a wide range of structurally different viruses with its possible application to viral epidemics.
The results of our present study indicate that the antiviral activity of CBD was not directed to one specific group of viruses but is effective against several enveloped and nonenveloped viruses.
This quality may become crucial when, under emergency conditions, it will be necessary to deploy quickly effective antiviral agents.
There was no opportunity for broad-spectrum antiviral agents that the SARS-CoV-2 pandemic in 2020 proved.
CBD has previously been proven to block many viruses and may become another handy weapon in fighting viruses; furthermore, its non-psychoactive nature and already-known safety profile make it appropriate for wide use.
Future Directions for CBD
With this capability of CBD as an antiviral broad-spectrum agent, many new roads can be opened about its research and possible applications.
Hence, detailed mechanisms of CBD antiviral activities in functions such as viral entry, replication, and assembly processes should be explored in the future.
