Preparation of Multifunctional Seaweed Polysaccharides Derivatives Composite Hydrogel to Protect Ultraviolet B‐Induced Photoaging In Vitro and In Vivo

Abstract Seaweed polysaccharides can be used for protective skin photoaging which is caused by long‐term exposure to ultraviolet B (UVB). In this study, a multifunctional composite hydrogel (FACP5) is prepared using sulfated galactofucan polysaccharides, alginate oligosaccharides as active ingredients, and polyacrylonitrile modified κ‐Carrageenan as substrate. The properties of FACP5 show that it has good water retention, spreadability, and adhesion. The antiphotoaging activity is evaluated in vitro and in vivo. In vitro experiments demonstrate that the components of FACP5 exhibit good biocompatibility, antioxidant, and anti‐tyrosinase activities, and could reduce the cell death rate induced by UVB. In vivo experiments demonstrate that, compared with the mice skin in model group, the skin water content treated with FACP5 increases by 29.80%; the thicknesses of epidermis and dermis decrease by 53.56% and 43.98%, respectively; the activities of catalase and superoxide dismutase increase by 1.59 and 0.72 times, respectively; the contents of interleukin‐6 and tumor necrosis factor‐α decrease by 19.21% and 17.85%, respectively; hydroxyproline content increases by 32.42%; the expression level of matrix metalloproteinase‐3 downregulates by 42.80%. These results indicate that FACP5 has skin barrier repairing, antioxidant, anti‐inflammatory, and inhibiting collagen degradation activies, FACP5 can be used as a skin protection remedy for photoaging.