Protection effect of donkey hide gelatin hydrolysates on UVB-induced photoaging of human skin fibroblasts

UVB irradiation is a potent photoaging factor and leads to the formation of skin wrinkles. The objective of this study was to investigate the mechanisms of UVB photoaging inhibition of low molecular weight peptides derived from donkey hide gelatin hydrolysates (LDGH) on human skin fibroblasts. The donkey hide was hydrolyzed using proteases, and the LDGH exhibited higher antioxidant activity than the original hydrolysate and inhibited collagenase and elastase activities. We also found that LDGH increases viability of Hs68 cells after UVB irradiation at 100 mJ/cm(2). Moreover, LDGH prevented the decrease in procollagen type I levels caused by exposure to UVB irradiation in Hs68 cells and reduced the up-regulated phosphorylation of p38, ERR, and JNK in the mitogen-activated protein kinase (MAPK) signaling pathway. These findings suggest that LDGH increases synthesis of procollagen type I by decreasing the phosphorylation of MAPK, therefore, LDGH may be useful as an effective anti-photoaging agent.