Photoaging induced by long-term exposure to UV irradiation and amelioration by Skipjack tuna skin hydrolysates: Targeting inhibition of MAPK and NF-κB signaling hyperactivation

Abstract

• Hydrolysates from Skipjack tuna (STH), rich of GADGSVTR, ameliorated photoaging. • STH reversed the imbalance of oxidative stress and inflammatory response. • STH restored the pathological impairment of photoaging skin. • STH targeted the hyperactivation of MAPK and NF-κB signaling pathways. Excessive and long-term exposure of skin to UV irradiation induces the photoaging and previous reports have revealed the roles of oxidative stress and inflammation response in photoaging progression, which provides the potential targets for photoaging intervention. Herein, the low molecular weight hydrolysates obtained from Skipjack tuna skin (STH) were used to evaluate the ameliorating effects on photoaging and the action mechanism was further explored. Pathologically, STH significantly recovered the barrier functions and restored the impaired architectures of photoaging skin. Biochemically, the antioxidant capacity was remarkably elevated and the inflammatory cytokines were significantly reduced in photoaging skin when STH was simultaneously administrated. Moreover, the abnormalities in epidermal hyperplasia and dermal loss were dramatically improved, along with the significant increase of procollagen type Ⅰ expression and inhibition of MMP-1 activity ( P < 0.05). Furthermore, STH mitigated the phosphorylation levels of p38, JNK, ERK, IκB and p65 in photoaging skin, which strongly indicated that STH synergistically intervened the photoaging progression in SD rats via cascading modulation on the hyperactivation of MAPK and NF-κB signaling pathways. Overall, these data prove the desirable protection of STH against photoaging process and can be used as functional ingredients in cosmeceutical foods.