Figure 2

The antioxidant NAC inhibits αSyn cytotoxicity. (a) Survival determined by clonogenicity of yeast cells expressing αSyn or harbouring the empty vector. Galactose growth medium (for promoter induction) has been supplemented or not with 20 mM or 30 mM NAC as indicated and cells were plated on YEPD agar plates at day 1 and day 2 to determine survival. Mean±S.E.M., n=12–18. Significances have been calculated for day 2, with ***P<0.001 and **P<0.01. (b) Flow cytometric quantification of oxidative stress by assessing the ROS-driven conversion of dihydroethidium to ethidium (DHE→Eth) of cells described in (a). Mean±S.E.M., n=8. Significances have been calculated for day 2, with ***P<0.001 and *P<0.05. (c) Representative micrographs of dihydroethidium to ethidium (DHE→Eth) staining of cells expressing αSyn or harbouring the empty vector after supplementation of galactose growth medium with 20 mM NAC for 2 days as flow cytometrically quantified in (b). (d) Determination of basal cytosolic Ca²⁺ levels using aequorin-based luminescence measurement of yeast cells expressing αSyn or harbouring the empty vector after growth on galactose media supplemented or not with indicated concentrations of NAC for 20 h. Data has been normalized to equally treated vector control cells. Mean±S.E.M., n=8; **P<0.01 and *P<0.05