Cannabinoids Receptors in COVID-19: Perpetrators and Victims

COVID-19 is caused by SARS-CoV-2 and leads to acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and extrapulmonary manifestations in severely affected cases. However, most of the affected cases are mild or asymptomatic. Cannabinoids (CBs) such as tetrahydrocannabinol (THC) and cannabidiol (CBD), which act on G-protein-coupled receptors called CB1 and CB2, have anti-inflammatory effects. Many published studies show that CBs are effective in various inflammatory disorders, viral infections, and attenuation of ALI and ARDS. Therefore, the present narrative review aimed to summarize the possible immunological role of CBs in COVID-19. The effects of CBs are controversial, although they have beneficial effects via CB2 receptors and adverse effects via CB1 receptors against ALI, ARDS, and hyperinflammation, which are hallmarks of COVID-19. The present narrative review has shown that CBs effectively manage ALI and ARDS by suppressing pro-inflammatory cytokines, which are common in COVID-19. Therefore, CBs may be used to manage COVID-19 because of their potent anti-inflammatory effects, suppressing pro-inflammatory cytokines and inhibiting inflammatory signaling pathways.