Four-Octyl Itaconate Attenuates UVB-Induced Melanocytes and Keratinocytes Apoptosis by Nrf2 Activation-Dependent ROS Inhibition

Figure 5

4-OI protected the skin of the mouse model from UVB-induced damage. (a) In the UVB group, the back of mice was exposed to UVB irradiation (400 mJ/cm²) once a day for 5 consecutive days. In the UVB with 4-OI group, mice were subjected to tail vein injection with 4-OI (10 mg/kg) every day for 6 consecutive days. UVB irradiation (400 mJ/cm²) started from the second day of 4-OI administration and for 5 consecutive days. All mice were sacrificed 24 h following the last UVB treatment. (b) The changes of mouse dorsal skin 24 h following the last UVB treatment with or without 4-OI treatment. (c) A constant skin area ( cm) of mouse dorsal back exposed to UVB was weighed. (d) Histopathological examination of skin area exposed to UVB exposure. The black lines represented epidermis thickness. Hematoxylin and eosin staining,  μm. (e) Epidermis thicknesses in each group were analyzed. Cell apoptosis in the epidermis was analyzed by (f) TUNEL staining and (g) analysis,  μm. Data were presented as (). versus the control group; ^# and ^## versus the UVB group.

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