硒对镉诱导的离体大鼠肝细胞DNA损伤的作用

Effects of selenium on rat hepatocellular DNA damage induced by cadmium in vitro

目的 研究亚硒酸钠对氯化镉诱导的离体大鼠肝细胞DNA损伤的影响。方法 用8 75 μmol/L、17 5 0 μmol/L和 35 0 0 μmol/L的亚硒酸钠分别与 8 75 μmol/L、17 5 0 μmol/L和 35 0 0μmol/L的氯化镉联合作用 ,用单细胞凝胶电泳检测大鼠肝细胞DNA损伤。 结果 8 75 μmol/L的亚硒酸钠对 8 75 μmol/L、17 5 0 μmol/L和 35 0 0 μmol/L的氯化镉引起的DNA损伤都有拮抗作用 ;17 5 0 μmol/L的亚硒酸钠对 17 5 0 μmol/L和 35 0 0 μmol/L的氯化镉显示拮抗作用 ,而对 8 75μmol/L氯化镉拮抗作用不明显 ;当亚硒酸钠为 35 0 0 μmol/L时 ,则对 8 75 μmol/L、17 5 0 μmol/L和35 0 0 μmol/L的氯化镉没有明显拮抗作用。从氯化镉的角度 ,当氯化镉为 8 75 μmol/L时 ,只有8 75 μmol/L亚硒酸钠拮抗作用最明显 ;当氯化镉为 17 5 0 μmol/L和 35 0 0 μmol/L时 ,8 75 μmol/L和 17 5 0 μmol/L的亚硒酸钠有拮抗作用 ,17 5 0 μmol/L的亚硒酸钠的拮抗作用又优于 8 75 μmol/L的亚硒酸钠。结论 一定剂量的亚硒酸钠拮抗一定剂量的氯化镉引起的DNA损伤与亚硒酸钠的剂量有关 ,随剂量增加 ,拮抗作用下降 ,而且也与亚硒酸钠和氯化镉的相对剂量有关。

Objectives This study was conducted to explore effects of selenium on rat hepatocellular DNA damage induced by cadmium in vitro . Method Sodium selenite was added at concentrations of 8.75, 17.50 and 35.00 μmol/L respectively with cadmium chloride at the concentrations of 8.75, 17.50 and 35.00 μmol/L respectively and rat hepatocellular DNA damage was measured with single cell gel electrophoresis (comet assay). Results Sodium selenite at the concentration of 8.75 μmol/L inhibited DNA damage caused by cadmium chloride at the concentration of 8.75, 17.50 and 35.00 μmol/L in rat liver cells ( P <0.05). Although sodium selenite at 17.50 μmol/L inhibited DNA damage induced by cadmium chloride at 17.50 and 35.00 μmol/L, it did not inhibit DNA damage induced by cadmium chloride at 8.75μmol/L. Sodium selenite at 35.00 μmol/L did not have antagonistic effects on DNA damage induced by cadmium chloride at 8.75, 17.50 and 35.00 μmol/L. In addition, sodium selenite at 8.75 μmol/L had the best antagonistic effect while cadmium chloride at 8.75 μmol/L, but the antagonistic effect of sodium selenite at 17.50 μmol/L was better than 8.75 μmol/L while cadmium chloride at 17.50 and 35.00 μmol/L. Conclusion The antagonistic effect of selenium on rat hepatocellular DNA damage induced by cadmium related to the concentrations of selenium and also to the concentration ratio between selenium and cadmium.