Gynostemma Pentaphyllum Hydrodistillate and Damulin B Prevent UVB-Induced Photoaging In Vitro and In Vivo via ROS Suppression and Restoration of MAPK/AP-1 and TGF-β/Smad Signaling

The study investigates the anti-photoaging effects of Gynostemma pentaphyllum hydrodistillate (GPHD) and Damulin B on UVB-induced skin damage. In HR-1 hairless mice, GPHD significantly reduced wrinkle formation, collagen degradation, and epidermal hyperplasia while enhancing skin hydration and elasticity. It also improved hyaluronic acid metabolism by increasing synthases and decreasing hyaluronidases. In UVB-irradiated Hs68 fibroblasts, both GPHD and Damulin B reduced reactive oxygen species (ROS) production, inhibiting MAPK/AP-1 signaling and restoring TGF-β/Smad activity, which supports extracellular matrix (ECM) stability. These findings suggest that GPHD and Damulin B effectively combat photoaging by reducing oxidative stress and modulating key signaling pathways for ECM remodeling and skin health.