Low molecular polypeptide from oyster hydrolysate recovers photoaging in SKH-1 hairless mice

When the human skin is chronically exposed to external stimuli such as ultraviolet (UV) radiation, the skin tissue suffers damage and the structure of the extracellular matrix (ECM) in the skin is disrupted. This eventually causes symptoms such as wrinkles loss of elasticity, skin sagging, and skin cancer. We previously found that hydrolysate extracted from pacific oyster (Crassostrea gigas) is effective in improving wrinkle formation. In this study, we selected a pentapeptide that was expected to have the most wrinkle reduction effect among the various peptides in oyster hydrolysate through preliminary in vitro screening and examined whether the pentapeptide derived from oyster hydrolysate (OHP) is effective in reducing wrinkles in vivo. We investigated the wrinkle-reducing effect of the OHP through 18-week SKH-1 hairless mice model. Our results showed that the OHP reduces wrinkles lengths, depths, and epidermal thickness which were increased by UVB radiation, and restores the amount of collagen. The OHP recovered the activity of antioxidant enzymes and regulated the expression of proinflammatory cytokines. We also found that OHP increases the expression of type I collagen through stimulating the TGFβ/Smad signaling pathway and inhibits the MMPs expression by regulating the MAPK/AP-1 signaling pathway. This study has shown that the OHP plays crucial roles in collagen production and wrinkle reduction in hairless mice and we proved the possibility of the OHP as a component for inhibiting wrinkle formation which was induced by photoaging.