目的研究不同剂量四溴双酚A对HepG2细胞的毒性并评估其剂量-反应关系。方法以不同质量浓度的TBBPA染毒HepG2细胞,采用光学显微镜观察细胞形态,MTS法检测细胞存活率,LDH检测试剂盒检测细胞LDH漏出率,NOAEL和BMD法评估其剂量-反应关系。结果TBBPA能引起HepG2细胞形态变化和存活率降低,24hTBBPA处理的HepG2细胞形态随TBBPA质量浓度升高,逐渐萎缩变圆;HepG2细胞存活率与TBBPA处理呈质量浓度-效应关系和时间-效应关系,其12、24和48h的IC50分别为33.82、27.36和17.73μmol/L;TBBPA能导致HepG2细胞的细胞膜损伤,12、24和48hTBBPA处理的HepG2细胞LDH漏出率与TBBPA有质量浓度-效应关系;选择TBBPA暴露24h对HepG2细胞的抑制率为健康效应终点,其NOAEL、LOAEL、BMDL10和BMD10分别为10、15、9.45和10.34μmol/L。结论TBBPA对HepG2细胞具有明显的细胞毒性,其基准剂量值为9.45μmol/L。
Objectives To investigate the cytotoxicity of HepG2 cells induced by tetrabromobisphenol A (TBBPA) and assess their dose-response relationship. Methods The morphology of HepG2 cells was observed by optical microscope; cell viability was measured by using MTS assay kit; the total release of cytoplasmic lactate dehydrogenase (LDH) in medium was measured by using LDH assay kit. The dose-response relationship was assessed by no observed adverse effect level (NOAEL) and benchmark dose (BMD) methods. Results The morphology of HepG2 cells could be affected by TBBPA, and there were dose-effect and time-effect relationship between the viability of HepG2 cells and TBBPA exposure. The IC50 were 33.82, 27.36 and 17.73 μmol/L for 12 h, 24 h and 48 h exposure respectively. There was dose-effect relationship between LDH release and TBBPA exposure in HepG2 cells after 12 h, 24 h and 48 h exposure. The inhibition rate of HepG2 cells after 24 h TBBPA exposure was selected as the endpoint, and the NOAEL, LOAEL, BMDL10 and BMDIO were 10, 15, 9.45 and 10.34 μmol/L respectively. Conclusions The results in the present study suggested that TBBPA exposure has cytotoxicity on HepG2 cells, and the value of BMDL10 for TBBPA exposure was 9.45 μmol/L while the inhibition rate after 24 h exposure was selected as the endpoint.