强脉冲光对长波紫外线Ⅰ诱导成纤维细胞光损伤的保护作用

摘要

目的 研究强脉冲光(intense pulse light,IPL)对长波紫外线(ultraviolet A,UVA Ⅰ)诱导的正常离体人皮肤成纤维细胞(fibroblast,FB)损伤的保护作用,探讨以IPL为手段的光子嫩肤技术的理论基础.方法 分离并培养人FB,用不同剂量UVA Ⅰ照射FB以诱导细胞光损伤,CCK-8检测其增殖能力的情况,根据预实验结果确定IPL剂量进行照射,流式细胞仪技术枪测细胞周期,Western印迹法检测CylinD1和CDK2蛋白的表达水平.结果 不同剂量的UVA Ⅰ可造成FB的损伤,随着UVA Ⅰ剂量的增加,细胞增殖能力下降,11 J/cm2的剂量可明显导致细胞大量死亡,而7 J/cm2的UVAⅠ对细胞的增殖能力没有明显的影响;经UVA Ⅰ照射2 d后再进行IPL连续照射2 d,细胞增殖活性高于单独UVA Ⅰ处理组,差异具有统计学意义.流式细胞仪检测结果表明该组细胞增殖指数升高.细胞周期蛋白CyclinD1和CDK2的表达水平升高.结论 IPL可通过调节周期蛋白的表达而促进正常FB增殖,从而保护UVAⅠ诱导的FB光损伤,为应用IPL面部美容除皱即光子嫩肤术提供理论依据.%Objective To study the protective effects of intense pulse light (IPL) on the injury of normal human skin fibroblasts (FB) induced by ultraviolet A (UVA Ⅰ ) in vitro and to explore its possible mechanism. Methods The human skin fibroblasts were isolated and cultured, and then irradiated by UVA Ⅰ (9 J/cm2) and IPL (15 J/cm2), respectively. The proliferative ability of the cells were detected by CCK-8. Cell cycle was detected by flow cytometry, and cylin D1 and CDK2 protein expression levels were detected by Western blot. Results Different doses of UVA Ⅰ irradiation caused certain damages of cultured fibroblasts. With the increasing of of UVA Ⅰ dose, cell proliferation was decreased. Cells went to death at the exposure to 11 J/cm2 UVA Ⅰ , while the proliferative activity did not change much at 7 J/cm2 UVA Ⅰ . Cells were treated with UVA Ⅰ for other 2 days, then with IPL irradiation for other 2days, showing clear stimulating to the cell proliferation as compared with the cells that received UVA Ⅰ treatment only. Flow cytometry results showed that an increase of cell proliferating index, and cell cycle protein cyclin D1 and CDK2 expression levels were also upregulated after IPL irradiation.Conclusion UVA Ⅰ irradiation may cause cell damage as showed by cell growth index, cyclin D1 and CDK2 expression, and this injury could be protected partly by IPL treatment. The intense pulsed light may regulate the expression of cyclin proteins that may promote normal fibroblast proliferation, which could be one of the mechanisms of IPL skin rejuvenation.