胆红素及牛黄拮抗苯乙烯所致肝癌细胞株损伤

Protective effect of bilirubin and natural cow-bezoar on styrene-induced HepG2 cell DNA strand breaks

目的 观察苯乙烯诱导的人肝癌细胞株 (HepG2 )细胞DNA链断裂损伤以及天然牛黄和胆红素对其损伤的拮抗效应。方法 采用单细胞凝胶电泳法观察HepG2细胞体外暴露于苯乙烯出现的DNA链断裂损伤 ,同时观察天然牛黄和胆红素对于苯乙烯诱导DNA损伤的拮抗作用。结果 在细胞存活未受到苯乙烯影响的浓度下 ,0 2μmol/L的苯乙烯即可诱导HepG2细胞明显的DNA链断裂损伤 ,彗星细胞频率和DNA迁移距离分别为 (9 5±2 1) %和 (4 5± 0 7) μm。在明显诱导DNA损伤浓度的苯乙烯处理时同时加入天然牛黄或胆红素 ,发现二者对苯乙烯诱导的DNA链断裂损伤在一定浓度下均有良好的拮抗作用 ,10 μmol/L的胆红素或天然牛黄与 1μmol/L的苯乙烯共同处理时 ,HepG2细胞的DNA损伤水平基本回复到本底水平。 结论 苯乙烯能够诱导HepG2细胞出现DNA链断裂损伤 ,10 μmol/L的胆红素或天然牛黄基本能完全拮抗苯乙烯诱导的DNA链断裂损伤。

Objective To observe the DNA strand breaks in HepG2 cell induced by styrene and to evaluate the antagonistic effect of natural cow-bezoar and bilirubin on DNA strand breaks induced by styrene.Methods Using SCGE (Single Cell Gel Electrophoresis) to detect the DNA strand breaks in HepG2 cell in vitro.Results Under the styrene concentration that the viability of HepG2 cell was not influenced,0.2μmol/L styrene could induce apparent DNA strand breaks in this kind of cell.The frequency and the migration of “comet” cell was (9.5±2.1)% and (4.5±0.7) μm,respectively.At the styrene concentration that could induce apparent DNA strand breaks natural cow-bezoar or bilirubin was added at the same time.Both natural cow-bezoar and bilirubin could reverse the DNA strand break induced by styrene in certain concentration.The co-treatment of 1μmol/L styrene and 10μmol/L natural cow-bezoar or bilirubin could counteract the effect of styrene almost thoroughly.Conclusion Styrene could induce DNA strand breaks in HepG2 cell and both natural cow-bezoar and bilirubin could antagonize such damage effect of styrene.