Survival of IhNSC at different O₂ conditions.

(A) Histogram showing the percentage of apoptotic cells (assessed by TUNEL assay, see methods) at 4, 8, 12 and 24 hours from dissociation (N = 3). Values are means±S.E.M. At 1% O₂ the percentage of apoptotic cells in culture is significantly higher than at other conditions at each time point (p<0.001 at 4h). The difference among all the values at the different oxygen concentrations was statistically significant (P<0.01) unless indicated (*P<0.05, n.s., = not significant); one-way ANOVA followed by the Student's t-test. (B) Graph showing the percentages of non apoptotic (na) or apoptotic (ap) cells as assessed by JC1 staining assay for the detection of cells with depolarized mitochondrial potential, corresponding to apoptotic cells (N = 2). Values are means±S.E.M. No significant differences were detected between the different conditions. (C) Representative images of live dissociated IhNSC in 1%, 2.5%, 5% and 20% oxygen plated onto an adhesive substrate and stained with the mitochondrial and nuclear dyes JC1 (red) and Hoechst (blue) at 4 hours upon dissociation. The images were obtained by merging the bright field and fluorescent (for JC1 and Hoechst) pictures of the cells. Scale bars: 10µm.