Jinyi Chen1, Jiefu Luo1, Yang Tan1, Mei Wang2, Zhihua Liu3, Tao Yang1, Xia Lei4. 1. Department of Dermatology, Daping Hospital, The Army Medical University, Chongqing, 400042, China. 2. Key Laboratory of Biorheological Science and Technology, Ministry of Education; Chongqing University, Chongqing, 400044, China. 3. Department of Stomatology, Daping Hospital, The Army Medical University, Chongqing, 400042, China. 4. Department of Dermatology, Daping Hospital, The Army Medical University, Chongqing, 400042, China. Electronic address: leixia1979@sina.com.
Abstract
OBJECTIVES: To investigate the effects of low-dose aminolevulinic acid photodynamic therapy (ALA-PDT) on photoaging in human dermal fibroblasts (HDFs) and to explore the mechanism of Nuclear factor erythroid 2-related factor 2(Nrf2)-mediated photorejuvenation in vitro. METHODS: A photoaging model was established through repeated exposure of HDFs to UVA. Total superoxide dismutase (SOD) expression was detected by a SOD activity assay. Nrf2 was knocked down through adenovirus infection, and successful knockdown was confirmed by Western blot analysis and quantitative polymerase chain reaction. RESULTS: Sustained exposure to UVA induced photoaging in HDFs. Total SOD activity was significantly increased by low-dose aminolevulinic acid (ALA)-PDT. Upon application of low doses of ALA-PDT to photoaging HDFs, Nrf2 was translocated to the nucleus; in addition, the expression of Nrf2, transforming growth factor-β1 (TGF-β1), type I and III collagen (COL1 and COL3), heme oxygenase 1 (HO-1), and p-ERK was increased, while the expression of matrix metalloproteinase 9 (MMP-9) was decreased. However, after Nrf2 was knocked down in HDFs, the expression of TGF-β1, COL1, COL3, and HO-1 was significantly decreased, while the expression of MMP-9 was increased. CONCLUSION: This study revealed that low-dose ALA-PDT decreases UVA-mediated photoaging through an Nrf2-mediated antioxidant effect.
OBJECTIVES: To investigate the effects of low-dose aminolevulinic acid photodynamic therapy (ALA-PDT) on photoaging in human dermal fibroblasts (HDFs) and to explore the mechanism of Nuclear factor erythroid 2-related factor 2(Nrf2)-mediated photorejuvenation in vitro. METHODS: A photoaging model was established through repeated exposure of HDFs to UVA. Total superoxide dismutase (SOD) expression was detected by a SOD activity assay. Nrf2 was knocked down through adenovirus infection, and successful knockdown was confirmed by Western blot analysis and quantitative polymerase chain reaction. RESULTS: Sustained exposure to UVA induced photoaging in HDFs. Total SOD activity was significantly increased by low-dose aminolevulinic acid (ALA)-PDT. Upon application of low doses of ALA-PDT to photoaging HDFs, Nrf2 was translocated to the nucleus; in addition, the expression of Nrf2, transforming growth factor-β1 (TGF-β1), type I and III collagen (COL1 and COL3), heme oxygenase 1 (HO-1), and p-ERK was increased, while the expression of matrix metalloproteinase 9 (MMP-9) was decreased. However, after Nrf2 was knocked down in HDFs, the expression of TGF-β1, COL1, COL3, and HO-1 was significantly decreased, while the expression of MMP-9 was increased. CONCLUSION: This study revealed that low-dose ALA-PDT decreases UVA-mediated photoaging through an Nrf2-mediated antioxidant effect.