Dose- and time-dependent α-synuclein aggregation induced by ferric iron in SK-N-SH cells

Objective: Intracellular formation of Lewy body (LB) is one of the hallmarks of Parkinson's disease. The main component of LB is aggregated α-synuclein, present in the substantia nigra where iron accumulation also occurs. The present study was aimed to study the relationship between iron and α-synuclein aggregation. Methods: SK-N-SH cells were treated with different concentrations of ferric iron for 24 h or 48 h. MTT assay was conducted to determine the cell viability. Thioflavine S staining was used to detect α-synuclein aggregation. Results: With the increase of iron concentration, the cell viability decreased significantly. At the concentrations of 5 mmol/L and 10 mmol/L, iron induced α-synuclein aggregation more severely than at the concentration of 1 mmol/L. Besides, 48-h treatment-induced aggregation was more severe than that induced by 24-h treatment, at the corresponding iron concentrations. Conclusion: Ferric iron can induce α-synuclein aggregation, which is toxic to the cells, in a dose- and time-dependent way.