PM2．5对HaCaT细胞的损伤作用及机制研究

Adverse effects of PM2.5 on HaCaT Cells and Relevant Mechanisms

【目的】探讨PM2.5对人永生化角质形成细胞（HaCaT）的损伤作用及NF-κB抑制剂PDTC对PM2.5致HaCaT细胞损伤作用的影响。【方法】将HaCaT细胞分别PM2.5、PDTC、PM2.5＋PDTC共孵育24h,同时设不加任何处理因素的正常组。24 h后收集细胞,测定细胞内丙二醛（MDA）含量、活性氧（ROS）水平、 超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-px）的活性以及NF-κB p65的蛋白表达情况。【结果】HaCaT细胞的存活率随PM2.5浓度的增加而下降,浓度为200、400、800μg/mL组的细胞存活率明显低于正常组（P〈0.05）。PM2.5组细胞中MDA含量、ROS水平和NF-κB p65蛋白表达水平显著高于正常组、PDTC组和PM2.5＋PDTC组（P〈0.05）,SOD、GSH-Px的活性显著低于上述各组（P〈0.05）。PM2.5＋PDTC组细胞中MDA含量、ROS水平和NF-κB p65蛋白表达水平显著高于正常组和PDTC 组。【结论】PM2.5能够降低HaCaT细胞的存活率。PM2.5能够对HaCaT细胞造成氧化损伤,而PDTC能够缓解这种损伤作用。应用NF-κB抑制剂PDTC可以特异性抑制NF-κB的表达,在一定程度上减轻PM2.5对HaCaT细胞的损伤作用。

【Objective】To explore the effects of PM2.5 on HaCaT cells and whether or not PDTC will alleviate the adverse effects caused by PM2.5.【Methods】HaCaT cells were co-cultured with PM2.5, PDTC, PM2.5＋PDTC for 24 hours, respectively. HaCaT cells without any treatment were set as control. The content of malondialdehyde （MDA）, reactive oxygen species （ROS） level, the activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px）_ and the expression of NF-kB in the cells from different groups were measured and compared.【Results】Cell viability decreased with the increasing of PM2.5 concentrations, the cell viabilities of 200, 400 and 800 μg/ml groups were significantly lower than the normal group （P〈0.05）. Compared with PM2.5 group, the MDA contents, the level of ROS and the expression of NF-kB of the cells treated with PM2.5＋PDTC, or PDTC, or vehicle treated cells were significantly lower while the activities of SOD and GSH-Px were significantly higher （P〈0.05）. Furthermore, the levels of MDA, ROS and NF-κB p65 protein in PM2.5 ＋ PDTC group were significantly higher than those in control group and PDTC group【Conclusion】PM2.5 was able to decrease the cell viability and cause oxidative damage to HaCaT cells while PDTC can alleviate the damages to certain extent.