PCB153对PBDE-47致SH-SY5Y细胞氧化应激和8-羟基脱氧鸟苷含量的影响

目的探讨PCB153和PBDE-47单独及联合染毒对SH-SY5Y细胞氧化应激及8-羟基脱氧鸟苷(8-OHdG)含量的影响。方法设DMSO溶剂对照组,1、5、10μmol/LPBDE-47(低、中、高)单独染毒组和与5μmol/LPCB153联合染毒组及相应的抗氧化剂组(N-乙酰-L-半胱氨酸NAC100μmol/L),分别对SH-SY5Y细胞染毒24h。用荧光染料DCFH-DA标记法和高效液相色谱-电化学技术(HPLC-ECD)分别检测细胞内活性氧(ROS)水平和8-OHdG的含量。结果随着染毒剂量的增加,PBDE-47单独染毒组ROS水平有逐渐增高的趋势,但与对照组及其相应的PCB153联合组相比,ROS水平无明显差异(P>0.05)。中、高联合染毒组ROS水平与对照组相比显著增加(P<0.05),并显著高于相应的单独剂量染毒组(P<0.05),加入抗氧化剂后细胞内ROS水平明显下降(P<0.05),细胞内ROS水平与PBDE-47染毒剂量呈现剂量-效应关系;高剂量PBDE-47单独染毒组和中、高剂量联合染毒组8-OHdG的含量与对照组相比均有明显的增加(P<0.05),高剂量联合染毒组8-OHdG含量明显高于相应的单独染毒组(P<0.05),加入抗氧化剂后其细胞内8-OHdG含量明显下降(P<0.05)。细胞内ROS水平与8-OHdG含量呈正相关关系(r=0.895)。结论一定剂量的PBDE-47可致DNA氧化损伤,PCB153可增加PBDE-47对SH-SY5Y细胞DNA的氧化损伤作用,提示活性氧在PBDE-47致DNA损伤方面发挥了重要作用。

Effects of PCB153 on oxidative stress and 8-OHdG content induced by PBDE-47 in human neuroblastoma cells in vitro

Objective To explore the effects of PCB153 (2,2,4,4,5,5-hexachlorobiphenyl) on oxidative stress and 8-OHdG (8-hydroxy-2'-deoxyguanosine) content induced by PBDE-47 (2,2,4,4-tetrabromodiphenyl ether) in SH-SY5Y cells. Methods SH-SY5Y cells were incubated with different concentrations of 1,5, 10μmol/L PBDE-47 or/and 5μmol/L PCB153 and antioxidant N-acetyl cysteine (NAC 100 μmol/L) for 24h in vitro, ROS (reactive oxygen species) level and 8-OHdG were measured by using DCFH-DA fluorescent marking method and the skill of high performance liquid chromatogram-electrochemistry (HPLC-EC), respectively. ResultsAs for ROS formation, there was no significant difference in PBDE-47 groups alone compared to the control group and their corresponding combined groups, respectively (P >0. 05). ROS formation were significantly increased in 5 and 10μmol/L combined groups compared to the control group and their corresponding concentrations of PBDE-47 groups or PCB153 group, respectively (P < 0.05). 8-OHdG levels were significantly increased in 10μmol/L PBDE-47, 5μmol/L PBDE-47 + 5μmol/L PCB153, and 10 μmol/L PBDE-47 + 5 μmol/L PCB153 groups compared with the control (P < 0.05). 8-OHdG level was dramatically increased in 10 μmol/L PBDE-47 + 5μmol/L PCB153 groups compared to their corresponding doses of PBDE-47 groups or PCB153 group (P < 0.05). The groups coineubation with N-aectylcysteine caused a decrease in cellular ROS level and ameliorated PBDE-47-mediated oxidative DNA damage effects. Positive relationship was observed between ROS level and 8-OHdG contents (r = 0. 895, P < 0.01). Conclusion These results provide evidence of a direct or indirect relationship between PBDE-47 and oxidative DNA damage. Furthermore, PBDE-47 combined with PCB153 may increase the effects on oxidative DNA damage in SH-SYSY cells in vitro, oxidative stress may responsible for DNA damage induced by PBDE-47.