Department of Chemistry, Tennessee State University, Nashville, Tennessee, USA.
Drug Chem Toxicol. 2013 Apr;36(2):155-62. doi: 10.3109/01480545.2012.660947. Epub 2012 May 27.
Effects of Cu(2+), Ni(2+) or Cu(2+) + Ni(2+) on lipid peroxide and glutathione (GSH) levels in U937 cells were investigated. Cells were treated with 0, 5, 10, and 20 µM of Cu(2+) and/or Ni(2+) and H(2)O(2) (0.01 mM) and incubated for 24 hours at 37°C. Lipid peroxides were measured by the thiobarbituric acid assay (TBA). GSH intracellular levels were assayed by the GSH assay kit from EMD/Calbiochem (San Diego, California, USA). Cu(2+) or Ni(2+) significantly (P < 0.01) increased lipid peroxides in a dose-dependent manner, compared to controls. The effect was more pronounced for Cu(2+), compared to the Ni(2+)-treated samples. Cu(2+) + Ni(2+) increased lipid peroxides in a significant (P < 0.001), dose-dependent manner, compared to Cu(2+) or Ni(2+) alone (i.e., ratio of 2.5:1-fold for combined versus single treatments, respectively). Cu(2+) or Ni(2+) significantly decreased GSH levels in U937 cells, with the effect being pronounced for Cu(2+). Cu(2+) + Ni(2+) metal ions significantly (P < 0.001) depleted cells of GSH in a dose-dependent manner. Ethylene diamine tetraacetic acid (EDTA) at 50 or 100 µM moderately reduced the Cu(2+)- or Ni(2+)-induced effects on GSH levels. Interestingly, GSH levels generally decreased to half (except for the combined metal dose of 20 µM at 100 µM EDTA) of its level at the highest metal concentration tested for both the single or combined treatments. In conclusion, multiple exposures of cells to metal ions may be lethal to cells, compared to their single treatments.
研究了 Cu(2+)、Ni(2+)或 Cu(2+) + Ni(2+)对 U937 细胞中脂质过氧化物和谷胱甘肽 (GSH)水平的影响。将细胞用 0、5、10 和 20 μM 的 Cu(2+)和/或 Ni(2+)以及 H(2)O(2)(0.01 mM)处理，并在 37°C 下孵育 24 小时。通过硫代巴比妥酸测定法 (TBA)测定脂质过氧化物。通过 EMD/Calbiochem (加利福尼亚州圣地亚哥)的 GSH 测定试剂盒测定 GSH 细胞内水平。与对照组相比，Cu(2+)或 Ni(2+)以剂量依赖的方式显著增加脂质过氧化物 (P < 0.01)。与 Ni(2+)处理的样品相比，Cu(2+)的作用更为明显。与单独的 Cu(2+)或 Ni(2+)相比，Cu(2+) + Ni(2+)以显著的 (P < 0.001)、剂量依赖的方式增加脂质过氧化物 (即，组合与单一处理相比，分别为 2.5:1 倍的比例)。Cu(2+)或 Ni(2+)显著降低 U937 细胞中的 GSH 水平，Cu(2+)的作用更为明显。Cu(2+) + Ni(2+)金属离子以剂量依赖的方式显著 (P < 0.001)耗竭细胞中的 GSH。50 或 100 μM 的乙二胺四乙酸 (EDTA) 适度降低 Cu(2+)或 Ni(2+)对 GSH 水平的诱导作用。有趣的是，除了在 100 μM EDTA 下最高金属浓度的两种单一或组合处理中，GSH 水平均降低到其最高金属浓度的一半(除了 20 μM 的联合金属剂量外)。总之，与单一处理相比，细胞多次暴露于金属离子可能对细胞具有致死作用。
