PI3K/Akt and ERK1/2 Signalling Are Involved in Quercetin-Mediated Neuroprotection against Copper-Induced Injury

Figure 2

Effects of quercetin on the survival of P19 neurons in the presence of excess copper. For the analysis of neuronal survival, P19 neurons (/well) were exposed to the indicated concentrations of CuSO₄ and quercetin in a 96-well plate for 24 h, and for 3 h with MTT afterwards. Precipitated formazan crystals were dissolved with DMSO, and the absorbance was recorded at 570 nm. In moderately injured neurons exposed to 0.5 mM CuSO₄, 150 μM quercetin improved neuronal survival (a). Treatment with 1 mM CuSO₄ induced more severe neuronal death. The presence of 30 μM quercetin further exacerbated the cytotoxic effects of copper, whereas a 150 μM concentration was without effect (b). Data represent the from four independent experiments performed in quadruplets. vs. cont (0 group); ^a and ^b vs. the copper-treated group (one-way ANOVA followed by Tukey’s test: (a) , ; (b) , ).

(a)

(b)