大气细颗粒物PM_(2.5)介导氧化应激对人角质形成细胞HaCaT凋亡的影响

Effects of Atmospheric Particulate Matter PM_(2.5) Mediated Oxidative Stress on the Apoptosis of Human Keratinocytes HaCaT Cells

目的研究大气细颗粒物PM_(2.5)对人角质形成细胞HaCaT的损伤作用及凋亡的影响。方法收集郑州市区空气中的PM_(2.5),分离并提取其水溶性及非水溶性成分,以不同的终浓度处理HaCaT细胞。CCK-8检测细胞增殖率,确定PM_(2.5)最佳作用浓度和时间。透射电子显微镜(TEM)检测细胞线粒体结构及细胞整体形态的变化。抗氧化剂N-乙酰-L-半胱氨酸(NAC)作用后,检测各组细胞内活性氧(ROS)水平、白细胞介素(IL)-1β和肿瘤坏死因子-α(TNF-α)的分泌水平及细胞凋亡率。结果在实验浓度和时间范围内,细胞增殖率随PM_(2.5)浓度和时间的增加而降低,具有显著的剂量和时间效应关系。TEM实验结果表明,PM_(2.5)作用后,细胞线粒体等超微结构表现出明显的损伤效应。与对照组相比,PM_(2.5)作用后细胞内ROS水平、IL-1β、TNF-α及细胞凋亡率均显著增加(P<0.05);与PM_(2.5)组相比,加入NAC后,ROS水平、IL-1β、TNF-α及细胞凋亡率均显著降低(P<0.05)。结论 PM_(2.5)能够对HaCaT造成明显的细胞氧化损伤,诱导炎性因子分泌和细胞凋亡;而NAC可以在一定程度降低氧化损伤、炎性因子分泌和细胞凋亡。

Objective To study the effects of air pollution particulate matter PM_(2.5) on the injury and apoptosis of Human immortalized keratinocyte(HaCaT cell lines).Methods PM_(2.5) was collected from the air of Zhengzhou.HaCaT cells were cultured and treated with different concentrations of water-soluble and water-insoluble extracts, which were separated and extracted from PM_(2.5).The cell viabilities were measured by CCK-8 to select optimal concentration and time of PM_(2.5).TEM was used to detect changes in mitochondrial structure and overall cell morphology.The contents of ROS,the concentrations of IL-1β and TNF-α and the apoptotic rates were detected after treatment of N-acetyl-L-cysteine(NAC).Results The cell viabilities decreased with increasing concentrations of PM_(2.5),showing an obvious time and dose dependence.The results of TEM experiments showed that the morphology and ultrastructure of the cells were damaged after PM_(2.5) treatment.Compared with the control group, the levels of ROS in PM_(2.5) group, the concentrations of IL-1β and TNF-α,and the apoptosis rate were significantly increased.Compared with the PM_(2.5) group, the levels of ROS,the concentrations of IL-1β and TNF-α,and the apoptosis rate were significantly lower after adding NAC,the difference was statistically significant(P<0.05).Conclusion PM_(2.5) may induce inflammatory factor secretion, cause oxidative damage, inducing inflammatory reactions and apoptosis in HaCaT cells.Additionally, antioxidants NAC could reduce oxidative damage, the secretion of inflammatory factors and cell apoptosis to a certain extent.