纳米二氧化硅对16HBE细胞存活率及PARP-1表达的影响

Effect of nano-SiO_2 on the survival and PARP-1 expression in 16HBE cells

目的探讨纳米二氧化硅(SiO_2)对人支气管上皮细胞(16HBE细胞)存活率和聚二磷酸腺苷核糖聚合酶-1(PARP-1)表达的影响。方法 (1)以质量浓度为0~100 mg/L纳米SiO_2处理16HBE细胞24.0 h,以CCK-8法检测细胞存活率。(2)将16HBE细胞分为6组:溶剂对照组(予等体积溶剂处理)、微米SiO_2对照组(予终质量浓度为20 mg/L微米SiO_2处理),5、10、20 mg/L纳米SiO_2组(予相应终质量浓度的纳米SiO_2处理),姜黄素组(先予终浓度为10μmol/L的姜黄素处理2.0 h,再予终质量浓度为20 mg/L的纳米SiO_2处理)。各组细胞经处理后,分别于培养4.0、12.0和24.0 h时间点收获细胞。采用荧光实时定量聚合酶链式反应检测细胞中PARP-1 mRNA的相对表达水平,以免疫印迹法检测PARP-1蛋白的相对表达水平。结果 (1)随着纳米SiO_2处理剂量的增加,细胞存活率下降,呈剂量-效应关系(P<0.01)。(2)在12.0和24.0 h时间点,纳米SiO_2刺激后,16HBE细胞的PARP-1 mRNA和蛋白相对表达水平均出现剂量依赖性下降(P<0.01);与同时间点溶剂对照组比较,5、10、20 mg/L纳米SiO_2组16HBE细胞在该2个时间点的PARP-1 mRNA和蛋白相对表达水平均下降(P<0.05)。在12.0和24.0 h时间点,20 mg/L纳米SiO_2组16HBE细胞的PARP-1 mRNA和蛋白相对表达水平均低于同时间点的微米SiO_2对照组(P<0.05);姜黄素组16HBE细胞的12.0 h时间点上述2个指标均高于20 mg/L纳米SiO_2组(P<0.05)。结论纳米SiO_2刺激可导致16HBE细胞存活率下降并呈剂量依赖性;PARP-1表达的下调可能是纳米SiO_2致16HBE增殖抑制的机制之一。姜黄素对纳米SiO_2诱导的16HBE的细胞损伤具有一定的保护作用。

Objective To explore the effects of nano-silicon dioxide（ SiO2） on the survival and poly（ ADP-ribose）polymerase-1（ PARP-1） expression in human bronchial epithelial cells（ 16 HBE cells）. Methods i） The 16 HBE cells were treated with nano-SiO2 at concentrations ranging from 0 to 100 mg/L for 24. 0 hours,and CCK-8 assay was used to examine cell viability. ii） The 16 HBE cells were divided into 6 groups： solvent control group（ equal volume solvent treatment）,micro-SiO2 control group（ treated with 20 mg/L micro-SiO2）,5,10,and 20 mg/L nano-SiO2 groups（ treated with the corresponding final dose of nano-SiO2）,and curcumin group. The curcumin group was given pretreatment with curcumin at a final concentration of 10 μmol/L for 2. 0 hours followed by treatment with a final concentration of 20 mg/L of nano-SiO2. Cells in each group were harvested at time points of 4. 0,12. 0 and 24. 0 hours after treatment. The relative expression of PARP-1 mRNA and protein in 16 HBE cells was detected by quantitative real-time polymerase chain reaction and Western blotting respectively. Results i） The survival of 16 HBE cells decreased with increasing nano-SiO2 treatment dose,showing a dose-effect relationship（ P〈0. 01）. ii） The expression of PARP-1 mRNA and protein in 16 HBE cells were dose-dependently decreased after nano-SiO2 stimulation at the 12. 0 and 24. 0 hours time points（ P〈0. 01）. The expression of PARP-1 mRNA and protein in 5,10,and 20 mg/L nano-SiO2 groups decreased at the above mentioned time points（ P〈0. 05）,compared with the solvent control group at the same time points. The expression of PARP-1 mRNA and protein in 20 mg/L nano-SiO2 group was lower than that in the micro-SiO2 control group at the same 12. 0 and 24. 0 hours time point（ P〈0. 05）. The above two indexes of cells were higher in curcumin group than that of 20 mg/L nano-SiO2 group at the 12. 0 hours time point（ P〈0. 05）. Conclusion Nano-SiO2 stimulation can lead to decrease survival of 16 HBE cells in a dose-dependent manner and down-regulation of PARP-1 expression may be one of the mechanisms of proliferation and inhibition of 16 HBE cells induced by nano-SiO2. Curcumin has certain protective effect on nano-SiO2-induced 16 HBE cell injury.