中文摘要：

目的研究5-氨基酮戊酸光动力疗法（ALA-PDT）对中波紫外线诱导的提前衰老（UVB-SIPS）成纤维细胞形态及增殖活性的影响。方法将不同浓度5-氨基酮戊酸（5-aminolevulinicacid，ALA）孵育UVB-SIPS成纤维细胞，不同时间点检测细胞内原卟啉IX（ProtoporphyrinIX，PpⅨ）荧光强度；1mmol／LALA孵育正常及UVB．SIPS成纤维细胞2h，6h，采用635nm红光以不同照光剂量处理后，倒置显微镜观察细胞形态、CellCountingKit-8（CCK-8）法检测细胞活性。结果1．00mm01／LALA孵育6h内，UVB-SIPS成纤维细胞内PpIX荧光强度逐渐增强，6～24h荧光强度逐渐减弱。ALA-PDT可诱导UVB-SIPS成纤维细胞形态改变、增殖减缓，与照光剂量及ALA孵育时间呈量效依赖关系，使用抗氧化剂NAC预处理可以减轻上述改变。结论ALA-PDT对UVB-SIPS成纤维细胞的增殖和生长有一定的抑制作用，其机制可能与ALA．PDT对细胞的氧化损伤有关。

英文摘要：

Objective To investigate the effects of 5-aminolevulinic acid photodynamic therapy （ALA-PDT） on the morphology and proliferation activity of UVB-induced premature senescent （UVB-SIPS） human skin fibro- blast. Methods Protoporphyrin IX （PpIX） fluorescence intensity was detected after normal and UVB-SIPS fibroblasts co-incubated with different concentrations of 5-aminolevulinic acid （ALA） at different time point. The cells treated with 1.0 mmol/L ALA for 2 and 6 hours were irradiated by a red laser （635 nm） at a pow- er density of 50 mW/cm2 and different light doses. Cell appearance was observed by a light microscopy. Cell Counting Kit-8 （ CCK-8 ） assay was performed to evaluate cell proliferation. Results After co-incubation with 1. Ommol/L ALA, the PpIX fluorescence intensity increased in 6 hours, reached a peak at the 6th hour, and decreased in 24 hours. ALA-PDT can induce morphology changes in UVB-SIPS fibroblasts, e.g. shrunken, disorganized, and degranulation. Cell proliferation decreased significantly. These all showed a dose-dependent manner with light dose and ALA incubation time. Pretreatment of NAC can reduce ALA-PDT induced cell morphology changes and proliferation rate at some extents. Conclusion ALA-PDT can induce obvious inhibitory effects on cell proliferation and growth, which may be related to the oxidative damage.