TY - JOUR
T1 - Oxidative stress and c-Jun-amino-terminal kinase activation involved in apoptosis of primary astrocytes induced by disulfiram-Cu2+ complex
AU - Chen, Sung Ho
AU - Liu, Shing Hwa
AU - Liang, Yu Chih
AU - Lin, Jen Kun
AU - Lin-Shiau, Shoei Yn
N1 - Funding Information:
This investigation was supported by the National Science Council (NSC 87-2314-B-002-085), Taipei, Taiwan.
PY - 2001/3/2
Y1 - 2001/3/2
N2 - Disulfiram is frequently used in the treatment of alcoholism. In this study, we found that CuCl2 (1-10 μM), but not other metal ions (Fe2+, Zn2+, Pb2+), markedly potentiated disulfiram-induced cytotoxicity by 440-fold in primary astrocytes. Thus, the molecular mechanisms of the cytotoxic effects induced by the disulfiram-Cu2+ complex were explored. The changes in morphology (nuclear condensation and apoptotic body formation) and hypodiploidy of DNA suggested that the disulfiram-Cu2+ complex induced an apoptotic process. Our studies of the death-signaling pathway reveal that decreased mitochondrial membrane potential, increased free radical production, and depletion of non-protein-thiols (glutathione) were involved. The disulfiram-Cu2+ complex activated c-Jun-amino-terminal kinase (JNK) and caspase-3 followed by poly (ADP-ribose) polymerase degradation in a time-dependent manner. Moreover, the cellular Cu content was markedly increased and the copper chelator bathocuproine disulfonate abolished all of these cellular events, suggesting that Cu2+ is essential for death signaling. The antioxidants N-acetylcysteine and vitamin C also inhibited the cytotoxic effect. Thus, we conclude that the disulfiram-Cu2+ complex induces apoptosis and perhaps necrosis at a late stage mediated by oxidative stress followed by sequential activation of JNK, caspase-3 and poly (ADP-ribose) polymerase degradation. These findings imply that the axonal degeneration and neurotoxicity observed after the chronic administration of disulfiram are perhaps, at least in part, due to the cytotoxic effect of the disulfiram-Cu2+ complex formed endogenously.
AB - Disulfiram is frequently used in the treatment of alcoholism. In this study, we found that CuCl2 (1-10 μM), but not other metal ions (Fe2+, Zn2+, Pb2+), markedly potentiated disulfiram-induced cytotoxicity by 440-fold in primary astrocytes. Thus, the molecular mechanisms of the cytotoxic effects induced by the disulfiram-Cu2+ complex were explored. The changes in morphology (nuclear condensation and apoptotic body formation) and hypodiploidy of DNA suggested that the disulfiram-Cu2+ complex induced an apoptotic process. Our studies of the death-signaling pathway reveal that decreased mitochondrial membrane potential, increased free radical production, and depletion of non-protein-thiols (glutathione) were involved. The disulfiram-Cu2+ complex activated c-Jun-amino-terminal kinase (JNK) and caspase-3 followed by poly (ADP-ribose) polymerase degradation in a time-dependent manner. Moreover, the cellular Cu content was markedly increased and the copper chelator bathocuproine disulfonate abolished all of these cellular events, suggesting that Cu2+ is essential for death signaling. The antioxidants N-acetylcysteine and vitamin C also inhibited the cytotoxic effect. Thus, we conclude that the disulfiram-Cu2+ complex induces apoptosis and perhaps necrosis at a late stage mediated by oxidative stress followed by sequential activation of JNK, caspase-3 and poly (ADP-ribose) polymerase degradation. These findings imply that the axonal degeneration and neurotoxicity observed after the chronic administration of disulfiram are perhaps, at least in part, due to the cytotoxic effect of the disulfiram-Cu2+ complex formed endogenously.
KW - Bathocuproine disulfonate
KW - Caspase-3
KW - Disulfiram
KW - Membrane potential
KW - Oxidative stress
KW - c-Jun-amino-terminal kinase (JNK)
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U2 - 10.1016/S0014-2999(01)00792-0
DO - 10.1016/S0014-2999(01)00792-0
M3 - Article
C2 - 11239917
AN - SCOPUS:0035794002
SN - 0014-2999
VL - 414
SP - 177
EP - 188
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
IS - 2-3
ER -