Bioactive Triple-Helical Recombinant Collagen Gels for Improved Healing of Sunburned Skin

Abstract

Excessive ultraviolet (UV) exposure can lead to sunburn, characterized by skin barrier damage, inflammation, pain, and an increased risk of skin cancer. Recombinant collagens have gradually attracted attention due to their high purity, low immunogenicity, batch-to-batch consistency, and excellent solubility. Additionally, the type of dressing significantly affects wound repair. Gels are ideal for sunburn treatment because they maintain a moist environment, adhere firmly, and do not need to be removed. Herein, we have created bioactive triple-helical recombinant collagen (THRC) gels for improved healing of sunburned skin. The THRC gels remained stable after a three-month stability test, displaying a rheological behavior characteristic of non-Newtonian pseudoplastic fluids. In vivo skin irritation tests conducted on New Zealand rabbits demonstrated that THRC gels were safe for use. A sunburned mice model was established to study the biological effects of THRC gels. Non-invasive combo evaluations indicated that THRC gels exhibited an exceptional capability of recovering dermis density, erythema index (EI), hydration, and transepidermal water loss (TEWL) of sunburned skin to a healthy state. Histological observations revealed that THRC gels significantly enhanced the repair of damaged skin by accelerating the recovery process, promoting collagen deposition and regeneration. Molecular biological characterizations further demonstrated their remarkable antioxidant properties, including the inhibition of lipoperoxidation and the enhancement in superoxide dismutase (SOD) and glutathione (GSH) activities. These safe and bioactive recombinant collagen gels provide a novel approach for sunburn repair and show potential for long-term cosmetic benefits.