Bio-Inspired Antioxidant Heparin-Mimetic Peptide Hydrogel for Radiation-Induced Skin Injury Repair.

Radiotherapy is one of the most important means of cancer treatment, however, radiation can also cause adverse reactions and even serious injuries to the skin. Radiation-induced excess reactive oxygen species (ROS) production and inflammatory infiltration make skin wounds difficult to heal compared to normal skin injuries. Herein, an antioxidant heparin-mimetic peptide hydrogel (K16, KYKYEYEYAGEGDSS-4Sa) is designed for radiation-induced skin injury (RISI) repair. First, the K16 peptide can self-assemble into a hydrogel with a 3D mesh-like porous nanofiber structure, which can provide certain physical support for skin repair like extracellular matrix (ECM). Then, K16 hydrogel not only scavenges ROS and prevents radiation damage to cellular DNA, but also promotes cell proliferation, migration, and angiogenesis. Meanwhile, 4-sulfobenzoic acid (4Sa) modified at the N-terminal end of the K16 peptide can adsorb inflammatory cytokines, thus acting to eliminate inflammation at the wound site. In vivo experiments showed that K16 hydrogel can inhibit early wound degradation, reduce inflammatory infiltration, and promote angiogenesis and collagen deposition, thus promoting wound healing. Therefore, the K16 hydrogel designed in this study has good potential for application in the field of radiation-induced skin injury repair.