砷诱发THP-1巨噬细胞氧化应激及抑制ABCA1表达诱导细胞凋亡

Arsenic exposure induces THP-1 macrophage oxidative stress, ABCA1 expression decrease and apoptosis

目的探究砷对THP-1巨噬细胞氧化应激和ABCA1基因表达的影响以及诱导细胞凋亡的可能机制。方法分别以0、4、8和12μmol偏亚砷酸钠染毒THP-1巨噬细胞48 h,抗氧化剂N-乙酰半胱氨酸(NAC)预处理1 h后,CCK-8检测细胞生存率;流式细胞术DCFH-DA染色法检测细胞内活性氧(ROS)的生成;RT-PCR检测细胞内ABCA1基因的表达。砷处理的同时加入50 g/L氧化型低密度脂蛋白(ox-LDL)培养48 h,油红O染色检测细胞内脂质富集,流式细胞术Annexin V-FITC/PI双染法检测细胞凋亡情况。结果随着砷处理浓度升高,ROS生成量明显上升(P<0.01);ABCA1基因表达下调(P<0.001);脂质富集和凋亡比例增加(P<0.05)差异有统计学意义。加入NAC后ROS产生明显下降;ABCA1基因表达上调(P<0.001);脂质富集和凋亡情况明显缓解(P<0.001),差异有统计学意义。结论砷能够通过氧化应激的途径诱导细胞凋亡,并下调ABCA1基因的表达,增强细胞内脂质富集。

Objective To investigate the effect of arsenic exposure on oxidative stress and ABCA1 gene expression of THP-1 macrophages and the possible mechanism of apoptosis.Methods THP-1 macrophage cells were treated with 0,4,8 and 12μmol/L NaAsO2 for 48 h respectively.After pretreatment 1 h with antioxidant n-acetyl cysteine(NAC),cell survival rate was examined by CCK-8.The production of reactive oxygen species was detected by flow cytometry DCFH-DA staining.The mRNA levels of ABCA1 were measured by RT-PCR.After pretreatment with 50 g/L ox-LDL for 48 h,the lipid accumulation in cells was tested by oil red O staining.Apoptosis was detected by flow cytometry Annexin v-FITC/PI double staining.Result ROS increased significantly(P<0.01),ABCA1 gene expression was down-regulated(P<0.001),lipid accumulation and apoptosis rate were increased(P<0.05)with the increasing of arsenic treatment concentration,which could be inhibited after pretreatment with NAC.Conclusion Arsenic can induce cell apoptosis,and decrease ABCA1 expression,increase lipid accumulation by THP-1 macrophage oxidative stress.