Proteomic analysis of the combined effects of cannabigerol and 3-O-ethyl ascorbic acid on kinase-dependent signalling in UVB-irradiated human keratinocytes

Oxidative stress induced by medium-wavelength ultraviolet radiation (UVB) is one of the most dangerous environmental stressors for the skin. Therefore, various medicinal remedies aim to prevent the harmful effects of UVB or support the recovery of the damaged cells. This study aimed to evaluate the impact of bioactive phytocannabinoid cannabigerol (CBG) together with 3-O-ethyl ascorbic acid (EAA), a stable, lipophilic derivative of the antioxidant vitamin C, on UVB-induced changes of proteome in cultured human keratinocytes 24 h after treatment. Surprisingly, proteomic analysis revealed very prominent CBG and EAA effects on kinases. These changes mainly influenced ERK1/2, IKK, MAP3K7, MAPK14, RIPK2, and NLK. Their expression was decreased by CBG and EAA, especially if used together after UVB-irradiation, so the effects of UVB were abolished restoring the profile of kinases to non-irradiated control. Moreover, CBG and EAA also reduced the UVB-induced modifications of proteins by the lipid peroxidation product 4-hydroxynonenal, especially in the case of AKT, Camkk1, cJun, ERK1, IKKα, MAPK11 and PERK. We conclude that, by maintaining proteome stability and kinase-dependent signalling, both CBG and EAA may support the recovery of human keratinocytes exposed to UVB radiation, especially if applied together, while the time-dependence of these effects should be further studied.