Selaginella tamariscina extract and amentoflavone ameliorate UVB-induced skin aging via AMPK activation

Ultraviolet exposure accelerates skin aging and increases the risk of skin-related diseases. Amentoflavone (AMF), the major compound isolated from selaginella tamariscina, was reported to exhibit potent antioxidant and anti-inflammatory properties. This study aims to investigate the therapeutic effects and mechanisms of the extract of S. tamariscina (STE) and AMF on ultraviolet B (UVB)-induced skin photoaging. In vitro and in vivo UVB-induced photoaging models were established to evaluate the anti-photoaging activities of STE and AMF. The therapeutic target of AMF was identified and analyzed using network pharmacology, combined with bioinformatic analyses and molecular docking. in vitro, STE significantly reduced UVB-induced oxidative stress and inflammation, while alleviating UVB-induced apoptosis. In vivo experiments further confirmed that both STE and AMF effectively mitigated UVB-induced skin injury. Mechanistically, AMF was shown to bind to AMP-activated protein kinase (AMPK), thereby promoting autophagy and protecting cells from UVB-induced damage. In conclusion, STE and its active compound AMF alleviate UVB-induced photoaging via AMPK activation, supporting their potential use in skin photoaging therapy.