Background We showed in our previous study that the N-terminal 17-mer peptide of amyloid precursor protein （APP17-mer peptide）,an active peptide segment with trophic and antioxidative effects,protects skin fibroblas...Background We showed in our previous study that the N-terminal 17-mer peptide of amyloid precursor protein （APP17-mer peptide）,an active peptide segment with trophic and antioxidative effects,protects skin fibroblasts against ultraviolet （UV） damage and downregulates matrix metalloproteinase 1 （MMP-1） expression.The aim of the current study was to explore the protective effects of P165,the N-terminal 5-mer peptide analog of amyloid precursor protein that is resistant to enzymolysis,on UVA-induced damage in human dermal fibroblasts （HDFs）.Methods HDFs were cultured in Dulbecco＆#39;s modified Eagle＆#39;s medium without and with P165 （concentrations were 1,10,and 100 μJmol/L）.Then,15 J/cm2 UVA irradiation was used to obtain the UV-irradiated model.Cell proliferation was analyzed using MTT kit.The collagen type Ⅰ and MMP-1 contents in cell lysate were determined by enzyme-linked immunosorbent assay （ELISA）.Fluorometric assays were performed to detect the formation of intracellular reactive oxygen species （ROS） in the cells.Results P165 significantly protected the HDFs against UVA-induced cytotoxicity.Compared with the UVA-irradiated control,1,10,and 100 μmol/L P165 elevated cell proliferation by 14.98% （P〈0.05）,17.52% （P〈0.01） and 28.34% （P〈0.001）,respectively.Simultaneously,10 and 100 μmol/L P165 increased collagen type Ⅰ content （both P〈0.05）.Moreover,P165 treatment （all concentrations） also markedly suppressed the UVA-induced MMP-1 expression （all P〈0.001）.P165 at 1,10,and 100 μmol/L also reduced UVA-induced ROS generation by 11.27%,13.69% （both P〈0.05）,and 25.48% （P〈0.001）,respectively.Conclusions P165 could protect the HDFs against UVA-induced photodamage,including cytotoxicity,and MMP-1 generation.Furthermore,it also increased the collagen type Ⅰ content in the cells.The inhibitory effect on intracellular ROS generation might be involved in these photoprotective effects.Thus,P165 may be a useful candidate in the prevention and treatment of skin photoaging.展开更多
基金This work was supported in part by a grant from the National Natural Science Foundation of China
文摘Background We showed in our previous study that the N-terminal 17-mer peptide of amyloid precursor protein （APP17-mer peptide）,an active peptide segment with trophic and antioxidative effects,protects skin fibroblasts against ultraviolet （UV） damage and downregulates matrix metalloproteinase 1 （MMP-1） expression.The aim of the current study was to explore the protective effects of P165,the N-terminal 5-mer peptide analog of amyloid precursor protein that is resistant to enzymolysis,on UVA-induced damage in human dermal fibroblasts （HDFs）.Methods HDFs were cultured in Dulbecco＆#39;s modified Eagle＆#39;s medium without and with P165 （concentrations were 1,10,and 100 μJmol/L）.Then,15 J/cm2 UVA irradiation was used to obtain the UV-irradiated model.Cell proliferation was analyzed using MTT kit.The collagen type Ⅰ and MMP-1 contents in cell lysate were determined by enzyme-linked immunosorbent assay （ELISA）.Fluorometric assays were performed to detect the formation of intracellular reactive oxygen species （ROS） in the cells.Results P165 significantly protected the HDFs against UVA-induced cytotoxicity.Compared with the UVA-irradiated control,1,10,and 100 μmol/L P165 elevated cell proliferation by 14.98% （P〈0.05）,17.52% （P〈0.01） and 28.34% （P〈0.001）,respectively.Simultaneously,10 and 100 μmol/L P165 increased collagen type Ⅰ content （both P〈0.05）.Moreover,P165 treatment （all concentrations） also markedly suppressed the UVA-induced MMP-1 expression （all P〈0.001）.P165 at 1,10,and 100 μmol/L also reduced UVA-induced ROS generation by 11.27%,13.69% （both P〈0.05）,and 25.48% （P〈0.001）,respectively.Conclusions P165 could protect the HDFs against UVA-induced photodamage,including cytotoxicity,and MMP-1 generation.Furthermore,it also increased the collagen type Ⅰ content in the cells.The inhibitory effect on intracellular ROS generation might be involved in these photoprotective effects.Thus,P165 may be a useful candidate in the prevention and treatment of skin photoaging.
