Cannabidiol Enhances Stress-Induced Cellular Damage: Potential Contribution of Kv2.1 Inhibition.

Kv2.1 channels, a subset of voltage-gated potassium channels, play critical roles in regulating cellular processes such as proliferation and apoptosis. While cannabidiol (CBD), a non-psychoactive phytocannabinoid, is known to modulate various ion channels, its specific effects on Kv2.1 channels remain largely unexplored. In this study, we investigated the influence of CBD on Kv2.1 channel activity and its impact on cell viability under both normal and stress conditions. To achieve stable Kv2.1 expression, HEK293 cells were transfected using the Sleeping Beauty transposon XB100 system. Puromycin (4 µg/mL) was used for selection over multiple passages. Cell viability and morphological changes were assessed using MTT assays and Giemsa staining under standard culture conditions (DMEM) and nutrient deprivation (ND) to simulate metabolic stress. CBD was applied in concentrations ranging from 3 to 3000 nM. Under standard conditions, CBD did not significantly affect cell viability during early exposure. However, under ND conditions, CBD-treated cells exhibited marked morphological deterioration and decreased viability, with these effects becoming more pronounced at higher CBD concentrations. Interestingly, Kv2.1-expressing cells showed improved baseline viability under ND, suggesting a protective role for the channel during metabolic stress. Electrophysiological analyses revealed that CBD inhibits Kv2.1 channel activity, primarily through enhanced channel inactivation. This inhibition increased cellular vulnerability to stress-induced damage. These findings reveal a dose-dependent interaction between CBD and Kv2.1 suggesting that Kv2.1 may be a relevant therapeutic target in pathological conditions such as tumor microenvironments, where cells experience oxidative stress and nutrient deprivation.