摘要
[目的]探讨微囊藻毒素(MC)与甲基硝基亚硝基胍(MNNG)对食管癌EC109细胞株毒性的联合作用。[方法]应用MTT法观察微囊藻毒素LR(MC-LR)(1 nmol/L、10 nmol/L、100 nmol/L、1μmol/L和10μmol/L)和MNNG(5 pmol/L、50 pmol/L、500 pmol/L、5 nmol/L、50 nmol/L、500 nmol/L和5μmol/L)对食管癌EC109细胞株生长抑制率(fa)的影响,利用析因设计方差分析和Chou-Talalay联合指数法(中效原理)分析两毒物的联合作用;应用流式细胞术检测细胞凋亡。[结果]MNNG单独染毒,当浓度达到50 pmol/L及以上时,各组fa均明显高于对照组(均P<0.05);MC-LR单独染毒,fa则先降低后增加,除100 nmol/L组外,其余组与对照组相比,差异均有统计学意义(均P<0.05);各浓度MC-LR与MNNG组联合染毒,fa均随着MNNG浓度升高而增加(r值分别为0.961,0.973,0.950,0.980,0.959,0.972,均P<0.01),各浓度MNNG与MC-LR组联合染毒,均随着MC-LR染毒浓度升高fa先降低后升高,与对照组相比差异有统计学意义(P<0.05);析因设计方差分析表明两毒物有交互作用(P<0.01);运用中效原理计算合用指数(CI),当fa=9.4%时,CI=1,两毒物联合呈现相加效应;当fa<9.4%时,CI>1,两毒物联合产生拮抗效应;当fa>9.4%时,CI<1,两毒物联合产生协同效应;流式细胞术检测细胞凋亡结果表明,MNNG与高剂量MC-LR均可诱导细胞凋亡,且高剂量MNNG与MC-LR联合染毒具有协同诱导细胞凋亡的作用。[结论]MC-LR与MNNG联合染毒,低剂量时两者为拮抗效应,高剂量时为协同效应。
[Objective] To investigate the combined toxicity effect of microcystins(MC) and N-methyl-N'-nitro-Nnitrosoguanidine(MNNG) on esophageal cancer cell line EC109. [Methods] The inhibition rates(fa) of microcystins(MC-LR)(1 nmol/L, 10 nmol/L, 100 nmol/L, 1 μmol/L, and 10 μmol/L) and MNNG(5 pmol/L, 50 pmol/L, 500 pmol/L, 5 nmol/L, 50 nmol/L, 500 nmol/L, and 5 μmol/L) on EC109 cells were observed by MTT assay. Factorial design and the Chou-Talalay method(medianeffect principle) were used to evaluate the combination effect. Apoptosis was examined by flow cytometric assay. [Results] Compared with the control group, when the exposure concentration was 50 pmol/L or more, the fa increased significantly in the cells treated with MNNG alone(all Ps〈0.05); whereas the fa decreased first and then increased in the cells treated with MC-LR alone, and except the 100 nmol/L group, significant differences were found in the rest treatment groups compared with the control group(all Ps〈0.05). Among all designed dosage combinations of MC-LR and MNNG, an increasing fa of EC109 cells was observed(r=0.961, 0.973, 0.950, 0.980, 0.959, 0.972, respectively, all Ps〈0.01) along with higher MNNG concentrations; while a reducing-and-thenincreasing pattern was found along with higher MC-LR, and the difference was statistically significant when compared with the control group(P〈0.05). The results of factorial design analysis of variance showed an interaction between the two toxins(P〈0.01). According to the Chou-Talalay method(combination index, CI), when fa=9.4%, CI=1, it indicated additivity; when fa9.4%, CI1, it indicated antagonism; when fa9.4%, CI1, it indicated synergism. The results of flow cytometry showed that apoptosis was induced by MNNG or high concentrations of MC-LR, and the combination with high concentrations of MNNG and MC-LR was synergistic on induction of apoptosis. [Conclusion] When MC-LR is combined with MNNG, the effect is antagonistic at low concentrations and synergistic at high concentrations.
出处
《环境与职业医学》
CAS
CSCD
北大核心
2016年第4期340-344,共5页
Journal of Environmental and Occupational Medicine
基金
国家自然科学基金项目(编号:81573108
81172747
81573191)
教育部新世纪优秀人才支持计划(编号:NCET-13-0124)