Mitochondria dysfunction was involved in copper-induced toxicity in MES23.5 cells.
OBJECTIVE
To investigate the toxicity of copper on MES23.5 dopaminergic cells and the probable mechanisms involved in this process.


METHODS
MES23.5 dopaminergic cells were selected as our experimental model. [3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyltetrazolium bromide] (MTT) assay was used to detect the influence of copper on the cell viability. The semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), Western blotting and the high performance liquid chromatography-electrochemical detection (HPLC-ECD) have been used to detect the tyrosine hydroxlase (TH) mRNA and protein expression and the dopamine content in MES23.5 cells. The flow cytometry have been used to detect the changes of mitochondrial transmembrane potential.


RESULTS
100 and 200 mumol/L copper had no effect on the MES23.5 cell viability, whereas 400 and 800 mumol/L of copper could decrease the cell viability (P < 0.01). Treating cells with 200 mumol/L copper for 24 h decreased the TH mRNA expression, the TH expression and the dopamine content compared with the control (P < 0.01, P < 0.01, P < 0.05, respectively). Besides, the mitochondrial transmembrane potential also decreased with the treatment of 200 mumol/L copper for 24 h (P < 0.01).


CONCLUSIONS
Copper could exert the toxic effects on MES23.5 dopaminergic cells and decrease the cell function. The dysfunction of mitochondria may be the mechanism of this toxicity effect.
Shi
Li-Min
LM
State Key Disciplines: Physiology (in incubation), Department of Physiology, Qingdao University, Qingdao 266071 China.
Jiang
Hong
H
Wang
Jun
J
Ma
Ze-Gang
ZG
Xie
Jun-Xia
JX
D000818:Animals; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics; D002478:Cells, Cultured; D003300:Copper / Q000378:metabolism / Q000633:toxicity*; D004298:Dopamine / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D006825:Hybridomas; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000235:genetics; D051379:Mice; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D009410:Nerve Degeneration / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D009498:Neurotoxins / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010300:Parkinson Disease / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D014446:Tyrosine 3-Monooxygenase / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
D009498:Neurotoxins; D012333:RNA, Messenger; D003300:Copper; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine