Could cannabigerol protect against neuroinflammation? Insights from an in vitro microglial study

Cannabigerol (CBG), a non-psychotropic cannabinoid from Cannabis sativa, has been investigated for its anti-inflammatory potential. However, its toxicological profile and the mechanisms underlying its effects are still poorly understood. This experimental study evaluated the safety and anti-inflammatory efficacy of CBG in BV-2 microglial cells, in a model of neuroinflammation. BV-2 cells were exposed to CBG concentrations ranging from 0.01 to 100 μM for 24 h to investigate non-cytotoxic doses. Colorimetric and fluorometric assays were performed in triplicate to assess cellular viability (MTT), the production of reactive oxygen species (ROS) and nitric oxide (NO), genotoxicity (GEMO and Alkaline Comet assay), and Caspase-1 gene expression. Cell morphology was also monitored microscopically. The results revealed that CBG 100 μM was highly cytotoxic, reducing cell viability by about 80 % and significantly increasing NO (approximately 400 %) and ROS (approximately 900 %) levels. Additionally, CBG was shown to be genotoxic in the GEMO assay at various concentrations, with 10 μM and 100 μM inducing DNA damage of approximately 200 % and 300 %, respectively. However, no genotoxicity was identified in the Comet assay. At higher concentrations, CBG also promoted the activation of microglia, altering their morphology. In a neuroinflammation model, CBG was unable to attenuate the increase in ROS levels induced by NLRP3 activation and promoted an increase in Caspase-1 gene expression. Despite a favorable safety profile at low doses, CBG exhibits inconsistent anti-inflammatory effects and can be genotoxic depending on the dose and exposure conditions.