, Volume 20, Issue 1, pp 1–11 | Cite as

Copper-1,10-Phenanthroline-Induced Apoptosis in Liver Carcinoma Bel-7402 Cells Associates with Copper Overload, Reactive Oxygen Species Production, Glutathione Depletion and Oxidative DNA Damage

  • Xiaoqiang Cai
  • Nina Pan
  • Guolin Zou


The mechanism of cytotoxicity on liver carcinoma Bel-7402 cells induced by copper-1,10-phenanthroline, Cu(OP)2, has been studied. Cell viability and apoptotic rate were examined in cells treated with Cu(OP)2 or Cu2+ alone. It was found that the apoptosis induced by Cu(OP)2 could not be induced by Cu2+ or OP alone in our experimental conditions. Total copper content in cells was measured by atomic absorption spectrophotometry, and the abnormal elevation of intracellular copper transported by lipophilic OP ligand may play the role of initial factor in the apoptosis, which caused subsequent redox state changes in cells. Intracellular levels of reactive oxygen species (ROS) were detected by fluorescent probe 2′,7′-dichlorofluorescein diacetate (DCFH-DA). Reduced (GSH) and total glutathione (GSSG + GSH) were determined by High-performance liquid chromatography (HPLC) after derivatization, and the ratios of GSH/GSSG were subsequently calculated. The overproduction of ROS and the decreased GSH/GSSG ratio were observed in cells which represented the occurrence of oxidative stress in the apoptosis. Oxidative DNA damage was also found in cells treated with Cu(OP)2 in the early stage of the apoptosis, and it suggests that the activation of DNA repair system may be involved in the pathway of the apoptosis induced by Cu(OP)2.


apoptosis copper-1 10-phenanthroline DNA damage glutathione reactive oxygen species 


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This work was supported by the grant from National Natural Science Foundation of China (Grant No. 30370366, 30470111) and The Research Fund for the Doctoral Program of Higher Education (RFDP).


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Copyright information

© Springer 2006

Authors and Affiliations

  1. 1.State Key Laboratory of Virology, Department of Biotechnology, College of Life SciencesWuhan UniversityWuhanChina

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