饮水氯化消毒副产物MX诱导人胚肝细胞氧化应激及其与DNA损伤的关系

目的研究饮水氯化消毒副产物3-氯-4-二氯甲基-5-羟基-2(5氢)-呋喃酮(MX)对体外培养的人胚胎肝细胞(L-02细胞)氧化应激的诱导。方法MX设10、30、100和300μmol/L4个暴露浓度,二甲基亚砜(DMSO,10ml/L)为溶剂对照,将L-02细胞染毒24小时后,检测L-02细胞内脂质过氧化产物丙二醛(MDA)、还原型谷胱甘肽(GSH)和8羟基脱氧鸟苷(8-OHdG)的含量。结果与溶剂对照相比,30、100和300μmol/L的MX能明显增加L-02细胞MDA含量(P<0.05,P<0.001,P<0.001),100、300μmol/L的MX使L-02细胞GSH水平显著性降低(P<0.001,P<0.001)、8-OHdG含量显著性增加(P<0.05,P<0.01)。在MX0~300μmol/L浓度范围内,L-02细胞的MDA含量与8-OHdG含量呈正相关(r=0.767,P<0.01);GSH水平与8-OHdG含量呈负相关(r=0.761,P<0.01)。结论MX可诱导L-02细胞氧化应激,使其脂质过氧化反应增强、抗氧化作用降低、DNA氧化损伤增加。MX引发的脂质过氧化反应和抗氧化力下降是DNA氧化损伤的影响因素之一。

Oxidative stress of human derived fetal hepatocytes induced by product of chlorinated drinking water(MX)

OBJECTIVE: To study the oxidative stress induced by 3-chloro-4-( dichloromethyl)-5-hydroxy-2 5H]-furanone (MX) (a product of chlorinated drinking water) in human derived fetal hepatocytes (L-02) in vitro. METHODS: L-02 cells were treated at the doses of 10, 30, 100 and 300 micromol/L of MX for 24h. Malondialdehyde (MDA), reduced glutathione (GSH) and 8-hydroxydeoxyguanosine (8-OHdG), the representative of antioxidative molecules and the marker of DNA oxidative damage respectively, were detected in L-02 cell treated by MX. Dimethyl sulfoxide (DMSO) was used as solvent control. RESULTS: (1) The content of MDA was significantly increased in L-02 cells etreated by MX at the doses of 30, 100, 300 micromol/L in comparison with solvent control. (2) The level of GSH was significantly decreased and the level of 8-OHdG was significantly increased in L-02 cells treated by MX at the concentration of 100, 300 micromol/L in comparison with solvent control. (3) There was a striking positive association between MDA content and 8-OHdG level (r = 0.767, P < 0.01) and a negative association between GSH level and 8-OHdG level (r = 0.761, P < 0.01) in L-02 cells treated by MX at the doses from 0 to 300 micromol/L. CONCLUSION: MX could induce oxidative stress in L-02 cells including increases of lipid peroxidation and DNA oxidative damage, and weakened effect of antioxidation. DNA oxidative damage in L-02 cells might be associated with lipid peroxidation and the weakening of antioxidation induced by MX.