Mitochondria dysfunction was involved in copper-induced toxicity in MES23.5 cells
Li-Min Shi1, Hong Jiang, Jun Wang
1State Key Disciplines: Physiology (in incubation), Department of Physiology, Qingdao University, Qingdao 266071 China.
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).
Conclusion:
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.
Insights
High copper concentrations (400 and 800 µmol/L) reduced dopaminergic cell viability. Copper exposure also decreased tyrosine hydroxylase (TH) expression and dopamine levels, suggesting mitochondrial dysfunction as a key toxicity mechanism.
Area of Science:
- Neuroscience
- Toxicology
- Cell Biology
Background:
- Dopaminergic neurons are crucial for motor control.
- Copper is an essential trace element but can be toxic at higher concentrations.
- Understanding copper toxicity mechanisms in dopaminergic cells is vital for neurodegenerative disease research.
Purpose of the Study:
- To investigate the toxic effects of copper on MES23.5 dopaminergic cells.
- To elucidate the underlying mechanisms of copper-induced toxicity.
- To assess the impact of copper on cell viability, dopamine synthesis, and mitochondrial function.
Main Methods:
- MES23.5 dopaminergic cells were used as the experimental model.
- Cell viability was assessed using the MTT assay.
- Tyrosine hydroxylase (TH) mRNA and protein expression were measured by RT-PCR and Western blotting, respectively.
- Dopamine content was quantified using High-Performance Liquid Chromatography with Electrochemical Detection (HPLC-ECD).
- Mitochondrial transmembrane potential was evaluated by flow cytometry.
Main Results:
- Copper concentrations of 400 and 800 µmol/L significantly decreased MES23.5 cell viability.
- Exposure to 200 µmol/L copper for 24 hours reduced TH mRNA and protein expression, as well as dopamine content.
- A significant decrease in mitochondrial transmembrane potential was observed following copper treatment.
- Lower copper concentrations (100 and 200 µmol/L) did not affect cell viability.
Conclusions:
- Copper exerts toxic effects on MES23.5 dopaminergic cells, impairing their function.
- Mitochondrial dysfunction appears to be a primary mechanism underlying copper toxicity in these cells.
- These findings contribute to understanding the role of copper dysregulation in neurotoxicity.
