2,4,4′-三氯联苯诱发微核和基因突变作用及其代谢酶依赖性  

PCB28 induces micronuclei and gene mutations with metabolizing enzyme dependence

作　　者：金桂芳 蔡露 张驰腾 姜浩[2] 刘云岗[2] JIN Gui-fang;CAI Lu;ZHANG Chi-teng;JIANG Hao;LIU Yun-gang(School of Pharmacy,Guangdong Pharmaceutical University,Guangzhou,510006,China;School of Public Health,Southern Medical University,Guangzhou 510515,China)

机构地区：[1]广东药科大学药学院,广东广州510006 [2]南方医科大学公共卫生学院,广东广州510515

出　　处：《毒理学杂志》2018年第6期452-456,共5页Journal of Toxicology

基　　金：广东省医学科研基金项目(A2016138);广东省自然科学基金面上项目(2015A030313272)

摘　　要：目的本课题组近年报道了非二噁英样多氯联苯化合物对哺乳动物细胞的致突变作用,且作用依赖于人细胞色素P450(CYP)2E1酶的代谢活化;本研究进一步探讨非二噁英样化合物2,4,4′-三氯联苯(PCB28)的致突变作用。方法采用CCK8法、微核实验和Hprt致突变实验检测PCB28对中国仓鼠V79和重组表达人和硫酸基转移酶(SULT)1A1的V79衍生细胞(V79-hCYP2E1-hSULT1A1)的细胞毒性和遗传毒性,并利用酶抑制剂观察重组表达的酶对于受试物毒效应的影响。结果PCB28(5~40μmol/L)经12h染毒、12h恢复,对V79-Mz和V79-hCYP2E1-hSULT1A1细胞均无细胞毒作用,1-氨基苯并三唑(60μmol/L,CYP抑制剂)和五氯苯酚(10μmol/L,SULT1抑制剂)的与受试物同时暴露于V79-hCYP2E1-hSULT1A1细胞对细胞活力影响甚微。PCB28在5~20μmol/L对V79-Mz细胞没有诱发微核的作用,但对V79-hCYP2E1-hSUT1A1细胞则明显增加其微核细胞率(P<0.05),且具有浓度依赖效应;此作用可被1-氨基苯并三唑明显降低,而被五氯苯酚明显增强。PCB28(10~40μmol/L)对V79-Mz细胞Hprt基因突变频率无影响,对V79-hCYP2E1-hSUT1A1细胞则诱发基因突变频率增加(P<0.05),其作用呈浓度相关性。结论PCB28可能经CYP2E1酶活化为致突变性代谢物,后者可由人SULT1A1酶代谢减毒;同其他非二噁英样多氯联苯类似,PCB28可能是一个由人CYP2E1酶活化的前致突变物。Objective It had been recently reported the potent mutagenicity of non-dioxin-like polychlorinated biphenyls and its dependence on metabolic activation by human cytochrome P450(CYP)2 E1 enzyme;To further investigate the muatgenicity of non-dioxin-like PCB28, an indicator PCB compound with relatively high burdens in the environment and human body. Methods CCK-8 assay, micronucleus test and Hprt mutagenicity assay were employed to investigate the cytotoxicity and genotoxicity of PCB28 in the Chinese hamster(V79)cell line and a V79-drived cell line genetically engineered for the expression of human CYP2 E1 and human sulfotransferase(SULT)1 A1(V79-hCYP2 E1-hSULT1 A1);through co-exposure of the latter cells to 1-aminobenzotriamine(ABT, 60 μmol/L, a CYP inhibitor) or pentachlorophenol(PCP, 10 μmol/L, a SULT1 inhibitor), the role of each enzyme in the effects of PCB 28 was analyzed. Result Under a 12 h/12 h exposure/recovery regime, PCB28(from 5 to 40 μmol/L) was not cytotoxic in V79-Mz or V79-hCYP2 E1-hSULT1 A1 cells;even in the presence of ABT or PCP, only mild cytotoxicity occurred at the highest test concentration. PCB28 at concentrations ranging from 5 to 20 μmol/L did not induce micronuclei in V79-Mz cells, however, it induced elevations in the frequency of micronucleated cells in V79-hCYP2 E1-hSULT1 A1(P<0.05), with concentration dependence;this effect was significantly reduced by ABT, while enhanced by PCP. PCB28(from 10 to 40 μmol/L) did not induce gene mutations in V79-Mz, however, it induced the increase in the frequency of Hprt mutations(P<0.05), and in the presence of concentration-effect relevance. Conclusion PCB28 may be activated by human CYP2 E1 to a mutagenic metabolite, which can be sulfo-conjugated by human SULT1 A1 to become nontoxic or weakly toxic;PCB28 might be a promutagen activated by human CYP2 E1 enzyme.

关 键 词：中国仓鼠V79细胞系 细胞色素P4502E1 2 4 4-三氯联苯 微核实验 Hprt基因突变试验 

分 类 号：R114[医药卫生—卫生毒理学]