INTRODUCTION: Microglial cells are the central nervous system's resident immune cells, responding to disturbances like aggregated proteins or ATP. Their activation can trigger chronic neuroinflammation, accelerating neurodegeneration in disorders such as Alzheimer's and Parkinson's. Targeting this process is critical, yet preventive medications are lacking, highlighting the need for new therapies.

AIM(S): Cannabidiol (CBD) and cannabigerol (CBG) have shown antioxidant and anti-inflammatory properties. This study aimed to investigate their impact, alone and in combination, on ATP-stimulated human microglial cells (HMC3) to determine their potential to mitigate neuroinflammation.

METHOD(S): Our research was based on the analysis of cell proliferation and the cytotoxicity of compounds, performed by Incucyte Live-Cell Imaging System. The study evaluated microglial markers associated with pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes, alongside apoptotic markers, to identify molecular targets modulated by CBD and CBG. The analysis included markers such as iNOS, IL-1β, SOD, NOX-4 ,TNF-α, and FAAH.

RESULTS: We observed a dose- and time-dependent effect of the tested compounds on the number of PI-positive dead cells. The number of dead cells increased over time in all conditions, but higher concentrations of the compounds resulted in a smaller increase compared to the control. This indicates a dose- and time-dependent cytoprotective effect. For our studies, selecting concentrations that maintain cell viability while ensuring activation and moderate expression of inflammatory factors was critical for obtaining biologically relevant results. The analysis of inflammatory marker expression confirmed that both CBD and CBG significantly modulate these pathways.

CONCLUSIONS: CBD and CBG effectively shift activated microglia toward a homeostatic, neuroprotective phenotype. These findings support their therapeutic potential in managing neuroinflammation.

FINANCIAL SUPPORT: This work was supported by National Science Center grant 2023/49/B/NZ7/02172.