In vitro, the photoprotective, cytotoxic and photomodifying properties of hexane and benzene extracts from the widely distributed in Belarus lichens Cladonia arbuscula, Evernia prunastri, Hypogymnia physodes, Ramalina pollinaria and Xanthoria parietina in the culture of human keratinocytes (HaCAT), are estimated. It was found that these extracts are not photoprotective, they have a photomodifying effect upon irradiation of keratinocyte cultures with ultraviolet light. Hexane extract of E. prunastri and benzene extracts of R. pollinaria and H. physodes at a concentration of 2.5 μg/ml are photoprotectors that weaken the effect of ultraviolet radiation by 1.6 ÷ 1.8 times. Extracts of C. arbuscula and X. parietina are photosensitizers – they increase the toxic effect of ultraviolet radiation by 10 or more times, regardless of the concentration of the extract in the nutrient medium. Hexane and benzene extracts of C. arbuscula and H. physodes lichens are cytotoxic to the HaCAT culture. With an increase in the dose of ultraviolet irradiation of keratinocytes from zero to lethal values, the benzene extract of R. pollinaria acted as a photoprotector at a concentration of 2.5 μg / ml, and as a photosensitizer at higher concentrations. The hexane and benzene extracts of E. prunastri and H. physodes exhibited sensitizing properties that increased with an increase in the concentration of lichen extracts. C. arbuscula hexane extract and X. parietina benzene extract were the most potent photosensitizers.
Epidermal p53 Response and Repair of Thymine Dimers in Human Skin after a Single Dose of Ultraviolet Radiation: Effects of Photoprotection
