不同粒径二氧化硅致人永生化表皮细胞氧化应激相关蛋白表达水平改变

目的探讨不同粒径二氧化硅(SiO2)染毒致人永生化表皮细胞(HaCaT)氧化应激相关的抗氧化酶:含铜与锌超氧化物歧化酶(SOD-1)、过氧化氢酶(CAT)和谷胱甘肽还原酶(GSR)蛋白表达水平的变化。方法不同质量浓度(5.0、10.0、15.0 mg/L)的15 nm和>100 nm的SiO2作用于HaCaT细胞24 h后,采用蛋白印迹法(Western blotting)观察各组细胞内SOD-1、CAT和GSR蛋白表达水平的变化。结果与对照组比较,不同粒径SiO2处理HaCaT后,细胞内SOD-1、CAT和GSR蛋白表达水平差异具有统计学意义(P<0.05)。对于15 nm组,SOD-1、CAT和GSR的蛋白表达水平随SiO2水平的增加呈现下降趋势;对于>100 nm组,3个蛋白的表达水平随SiO2水平的增加而上调。结论不同粒径SiO2的处理下,细胞内SOD-1、CAT和GSR等氧化应激相关抗氧化酶蛋白表达水平呈现明显的变化,提示SiO2诱导的生物学效应与粒径有关。

Effects of nano-sized and micro-sized silicon dioxide on expression levels of antioxidant enzymes in HaCaT cells

Objective To explore the effects of 15 nm and >100 nm SiO2 on expression levels of 3 oxidative-stress-related proteins including Cu-Zn superoxide dismutase-1(SOD-1),catalase(CAT) and glutathione reductase(GSR) in HaCaT cells. Methods HaCaT cells were treated with 15 nm and >100 nm SiO2 at the concentrations of 5.0,10.0,15.0 mg/L for 24 hours,respectively.The protein levels of SOD-1,CAT and GSR were analyzed by the method of Western blotting. Results Compared with those of the control,the treatment with 15 nm and >100 nm SiO2 could significantly alter the expression levels of SOD-1,CAT and GSR.When treated with 15 nm SiO2,the changes of SOD-1,CAT and GSH were down-regulated along with the SiO2 concentration increased.On the other hand,these 3 antioxidant enzymes were up-regulated along with >100 nm SiO2 concentration increased. Conclusion The data indicated that alternation of protein levels of antioxidant enzymes could be involved in cytotoxicity of HaCaT cells induced by 15 nm and >100 nm SiO2.The biological effects were related closely with particle size in HaCaT cells.