Saponins from Dioscorea nipponinca Makino rehabilitate UVB-induced skin photoaging by inhibiting oxidative stress and apoptosis via targeting STAT3.

BACKGROUND

Skin photoaging is one of the main causes of disability, and there are few effective methods for the treatment. In recent years, some studies have demonstrated that natural saponins have bioactivity against skin photoaging. However, the pharmacological data, targets and molecular mechanisms are limited. Dioscorea nipponinca Makino processes various pharmacological actions. To date, there have been no reports on the actions of it against skin photoaging.

PURPOSE: Total saponins from D. nipponinca Makino (TSDN) were isolated for investigating the activity and mechanisms against skin photoaging.

METHODS

UPLC-MS/MS was used for chemical identification and determination. The skin photoaging model was constructed by UVB irradiation on HaCaT cells and C57/BL mice. The activity of TSDN was evaluated by biochemical and pathological analyses. The potential targets of the components in TSDN were predicted by the Swiss Target Prediction database. The binding relationships between the components and the target were verified by molecular docking, molecular dynamics simulation, cell thermal shift assay (CETSA) and surface plasmon resonance (SPR). The molecular mechanism underlying the anti-photoaging of TSND was further investigated by gene overexpression, immunofluorescence and western blotting tests.

RESULTS

TSDN, primarily containing diosgenin, dioscin, trillin, pseudoproto -dioscin and protodioscin, exhibited significant protective effects against skin photoaging by attenuating UVB-induced oxidative stress and apoptosis. STAT3 was the target of TSDN against skin photoaging. After overexpression of STAT3, TSDN lost its ability to resist skin photoaging, which was also no longer able to adjust the signal.

CONCLUSION

TSDN showed the potential to rehabilitate UVB-induced skin photoaging by inhibiting oxidative stress and apoptosis via targeting of STAT3.