Autocatalytic\nCeria Nanoparticle-Embedded Tilapia\nCollagen Hydrogels as Enhanced Antioxidative and Long-Lasting Dermal\nFillers for Photoaged Skin

Excessive\nreactive oxygen species (ROS) generated by ultraviolet\n(UV) irradiation significantly contribute to photoaging by increasing\nthe level of matrix metalloproteinases (MMPs), accelerating collagen\ndegradation. Commercial dermal fillers offer temporary wrinkle reduction\nvia volume enhancement. In this study, we propose tilapia-derived\ncollagen hydrogels embedded with ceria nanoparticles (Ce@Col gels)\nas long-lasting dermal fillers for UVB-induced photoaging. Ceria\nnanoparticles (CeNPs) significantly enhance the stability of the collagen\nmatrix against enzymatic degradation. These gels exhibit mechanical\nstability and injectability comparable to those of commercial alternatives.\nAdditionally, CeNPs effectively eliminate ROS to suppress MMP production,\ncurbing both collagen degradation and inflammatory responses. In a\nUVB-induced photoaging mouse model, the Ce@Col gels significantly\nreduced the level of oxidative stress in the skin, decreased the number\nof wrinkles, reduced epidermal thickness, and decreased levels of\naging-related biomarkers while increasing the level of collagen deposition.\nThese antiaging effects persisted for seven months post-injection,\nhighlighting Ce@Col gels as a promising approach for prolonged collagen\nregeneration and sustained anti-inflammatory benefits in photoaged\nskin.