人支气管上皮细胞5-脂氧合酶介导4-氨基联苯的活化及DNA损伤  

Activation of 4-aminobiphenyl mediated by 5-lipoxygenase and DNA damage in human bronchial epithelial cells

作　　者：朱宏翔[1,2] 胡建安[1] 黄云[1] 武越[1] 熊敏如[1] 

机构地区：[1]中南大学公共卫生学院劳动卫生与环境卫生学系,湖南长沙410078 [2]湖南省劳动卫生职业病防治所控制评价科,湖南长沙410007

出　　处：《中国药理学与毒理学杂志》2011年第2期193-200,共8页Chinese Journal of Pharmacology and Toxicology

基　　金：教育部高等学校博士学科点专项科研基金(200605330210);湖南省自然科学基金(07JJ3077)~~

摘　　要：目的探讨人支气管上皮(HBE)细胞内5-脂氧合酶(5-LOX)对4-氨基联苯(4-ABP)的氧化活化及所致DNA损伤,为LOX作为前致癌物氧化活化的代谢途径提供依据。方法①体外酶系统实验:4-ABP在含有大豆脂氧合酶(SLO)的体外酶体系中反应,用分光光度法检测体系中反应产物生成。②细胞实验:4-ABP 100～800μmol.L-1染毒HBE细胞,MTT法检测HBE细胞存活率;Western印迹法检测5-LOX蛋白表达;单细胞凝胶电泳检测DNA损伤。同时,检测特异性5-LOX抑制剂AA861对5-LOX蛋白表达和多种酶抑制剂对细胞存活率和DNA损伤的影响。结果在过氧化氢参与下,SLO可以协同氧化4-ABP,LOX抑制剂去甲二氢愈创木酸可抑制该协同氧化作用。4-ABP可以使HBE细胞内5-LOX蛋白表达增加,AA861对5-LOX蛋白表达没有影响;4-ABP 400μmol.L-1可以使HBE细胞产生明显的DNA损伤,彗星细胞的阳性率达47.7%(P<0.01),AA861和萘普生可以抑制该浓度4-ABP所致的DNA损伤,最大保护率分别为58.1%和21.7%。结论 4-ABP上调HBE的5-LOX蛋白表达。5-LOX可能通过介导4-ABP协同氧化,导致DNA损伤,这可能是4-ABP致癌的机制之一。OBJECTIVE To investigate the effect of 4-aminobiphenyl（4-ABP） on 5-lipoxygenase（5-LOX） protein expression,cytotoxicity and DNA damage in human bronchial epithelial（HBE）cells,and to provide envidence that LOX is a pathway for oxidation and activation of precarcino-gens.METHODS ① Enzymatic experiment： soybean lipoxygenase（SLO）,substrate（4-ABP）and other components reacted in an enzymic system;the product was detected with spectrophotome-try.② Cellular experiment： The effect of 4-ABP on the cellular survival rate was assessed by reduc-tion of tetrazolium dye（MTT） in cultured HBE cells.After HBE cells were exposed to 4-ABP 100-800 μmol.L-1 for 4 h,the protein expression of 5-LOX in HEB cells was tested by Western blot-ting,and DNA damage by single cell gel electrophoresis.Finally the effect of a specific inhibitors of5-LOX,AA861,on 5-LOX protein expression and DNA damage in the cells was detected.RESULTS SLO catalyzed the co-oxidation of 4-ABP in the presence of hydrogen peroxide.Nordi-hydroguaiaretic acid（NDGA） inhibited the oxidation of 4-ABP by SLO,seemingly in a concentra-tion-dependent manner and with in a special range.4-ABP induced 5-LOX protein expression,butAA861 was invalid in HBE.4-ABP caused toxic action and DNA damage in HBE,as the positiverate comet cells was increased to 47.7% by 4-ABP at the concentration of 400 μmol.L^-1.Suchdamage could be significantly inhibited by AA861 and naproxen with a maximum rate of protection of58.1% and 21.7%,respectively.CONCLUSION 4-ABP can regulate 5-LOX protein expressionin HBE cells.The co-oxidation of 4-ABP with 5-LOX could induce DNA damage,which could beone of the mechanisms for carcinogenesis of 4-ABP.

关 键 词：花生四烯酸盐5-脂氧合酶 氨基联苯化合物 药物协同作用 DNA损伤 

分 类 号：R346[医药卫生—基础医学]