Figure 3.

SY5Y-APP cells were less sensitive to toxic insults. Cells were exposed to H₂O₂ pulse (5 min), followed by incubation with fresh medium for different times (1, 4 and 24 h). (a) Cell viability was evaluated 24 h after oxidative insults by MTT assay. Data were expressed as % of cell survival versus respective controls. Values are the mean±S.E.M. of three different experiments. *P<0.001 H₂O₂- treated mock versus control mock. (b) Protein extracts derived from mock and SY5-APP cells at 1 and 4 h after H₂O₂ pulse were processed for western blot analysis with anti-p53, anti-p21 antibodies. Nucleolin was used for sample normalization. (c) Mock and SY5Y-APP cells were transfected with p53AIP1-luc promoter and 18 h later they were treated with 50 μℳ doxorubicin (Doxo). As much as 24 h after toxic insult, cells were processed for the measurement of luciferase activity. Data were expressed as % of relative luminescence unit (RLU) ***P<0.0001 Doxo-treated mock versus control mock