Collagen and Collagen Peptide From the Alosa Sapidissima Protect Against UVB-Induced Skin Damage.

Ultraviolet-B (UVB) radiation exacerbates oxidative stress, accelerating collagen degradation and skin aging. While collagen and its hydrolysates offer therapeutic potential, medical apparatus and instruments call for high quality and traceability. Here we investigated the synergistic effects of collagen and collagen peptides derived from Shad (Alosa sapidissima) scales against UVB-induced skin damage. Collagen was extracted and peptides were obtained through enzymatic hydrolysis. Structural characterization confirmed collagen's triple helix and peptide fragments. In vitro assays demonstrated concentration-dependent antioxidant activity: collagen peptides (5%-10%) and collagen (0.5%-1%) exhibited potent DPPH/ABTS⁺ radical scavenging, with their combination outperforming individual components. In UVB-irradiated mice, topical application of the collagen-peptide mixture significantly reduced epidermal thickening, suppressed ROS production, and enhanced SOD activity. Histological analysis revealed mitigated wrinkle formation and improved dermal blood flow. The mixture also formed stable hydrogels, enhancing bioavailability. These findings highlight the dual mechanism of collagen (structural support) and peptides (antioxidant/moisturizing effects), offering a promising strategy for combating photoaging. This study provides foundational insights for developing marine collagen-based dermatological therapies.