Neferine prevents ultraviolet radiation-induced skin photoaging.

The aim of the present study was to evaluate the anti-photoaging effect of neferine upon exposure of mice to ultraviolet (UV) radiation. An photoaging model was established by repeatedly exposing mouse dorsal skin to UV-A and UV-B radiation for 12 weeks. Through skin photographs, hematoxylin and eosin staining, Masson's trichrome staining, and scanning and transmission electron microscopy, skin wrinkles, epidermal thickness and dermal collagen were analyzed in the UV-irradiated mouse skin. Furthermore, the levels of endogenous antioxidants, namely superoxide dismutase (SOD) and glutathione peroxidase (GPx), were measured to determine the extent of UV-induced oxidative stress that was associated with photoaging. The results demonstrated that the topical application of neferine following UV irradiation reduced oxidative stress by increasing SOD and GPx activities, and attenuated the photoaging process. Histological and ultrastructural examination revealed that neferine delayed skin wrinkle formation by inhibiting epidermal hypertrophy and collagen loss and degradation. In conclusion, the results of the present study indicated that neferine effectively prevents UV-induced skin photoaging and photodamage.