摘要:
研究纳米硫化镉(Nano-CdS)材料对肺癌细胞系A549的毒性及氧化损伤作用。培养A549细胞,经传代后接种于6孔板中,每孔2 mL完全培养基,接种次日进行染毒。用直径20~30 nm、长度80~100 nm的Nano-CdS进行染毒,染毒浓度分别为0、5、10、20、40和80 mg·L-1。染毒24 h后用MTT检测细胞存活率,以存活率在80%左右的浓度为后续实验染毒浓度。应用流式细胞技术,用荧光探针法检测A549细胞的活性氧(reactive oxygen species, ROS)含量,PI-Annexin-V法检测细胞凋亡情况;用试剂盒检测细胞中超氧化物岐化酶(superoxide dismutase, SOD)和过氧化氢酶(catalase, CAT)活性以及丙二醛(malondialdehyde, MDA)含量,判断细胞氧化损伤情况。不同浓度Nano-CdS处理细胞24 h之后,细胞存活率随剂量的增加而下降,浓度为10、20、40和80 µg·L-1时,存活率分别为(88.71%±0.80%)、(81.93%±3.06%)、(75.23%±1.13%)和(70.66%±5.63%),且各组间差异均具有统计学意义(P< 0.05)。以浓度为10和20 mg·L-1的Nano-CdS染毒24 h后,胞内ROS含量和细胞凋亡率随染毒剂量的增加而增加(P<0.05);浓度为10 mg·L-1时,细胞凋亡率为(6.26%±0.44%)。与对照相比,各染毒组SOD和CAT活性和MDA含量升高,20 mg·L-1染毒组SOD和CAT活性和MDA含量高于10 mg·L-1染毒组(P< 0.05)。研究表明,纳米硫化镉能引起A549细胞的氧化损伤和细胞凋亡,具有明显的细胞毒性。
Abstract:
This paper aims to investigate the oxidative damage of the lung cancer cell line A549 following nanometer cadmium sulfide (Nano-CdS) exposure. A549 cells were cultured in 6-well plates with 2 mL complete medium and then treated with Nano-CdS for 24 h, whose diameters ranged from 20 to 30 nm and lengths were from 80 to 100 nm. The doses of Nano-CdS were 0, 5, 10, 20, 40 and 80 mg·L-1 respectively. MTT colorimetric assay was used to detect the cell survival rate, and the dose resulting in 80% cell survival rate was used as subsequent exposure dose. Flow cytometry was applied to detected the reactive oxygen species (ROS) contents of A549. The cell apoptosis was assayed by using PI-Annexin-V. The activities of SOD and CAT, the content of MDA were detected with the kits. After treatment with different concentrations of Nano-CdS for 24 h, the survival rates of cells were (88.71%±0.80%), (81.93%±3.06%), (75.23%±1.13%) and (70.66%±5.63%) respectively at doses of 10, 20, 40 and 80 mg·L-1, showing a signficant decrease (P<0.05) with Nano-CdS dose increase. Intracellular ROS contents and apoptosis rate of cells increased significantly after being treated with 10 or 20 mg·L-1 Nano-CdS, compared with the control (P<0.05). The apoptosis rates were (6.26%±0.44%) and (8.94%±1.38%) at 10 and 20 mg·L-1 Nano-CdS groups. Compared with control, the activities of SOD and CAT, and the content of MDA all increased. The activities of SOD and CAT, and the content of MDA in 20 mg·L-1 exposure group were significantly higher compared to 10 mg·L-1 exposure group (P<0.05). It is indicated that Nano-CdS exposure can cause oxidative damage and apoptosis in A549 cells and then result in cytotoxicity.