Fig. 1

Cellular senescence of NSCs^WT after repeated passages in culture. A. Sequences of CT4 and mCT4 peptides. B. Number of NSCs^WT after each passage. CT4 at 5 μM once every other day increased the number of NSCs at every passage. C. CT4 doubled the size of neurospheres at P5. a), representative image, scale bar: 100 μm. b) quantification of the diameter of spheres. D. Levels of hSOD1 detected by western blot in NSCs^WT treated with CT4 or mCT4. Full-length blots are presented in Additional file 1: Fig. 1D. a) gel image; b) densitometry. E. Levels of hSOD1 detected by ELISA in NSCs^WT treated with CT4 or mCT4. F. Levels of misfolded hSOD1 detected by Western blot. Full-length blots are presented in Additional file 1: Fig. 1F. a) gel image; b) densitometry. G. Thiol-disulfide status of the hSOD1 in NSCs^WT treated with CT4 or mCT4 at P3 and P5. The thiol content was normalized to total hSOD1. For C and F, Student’s t-test. Two-way ANOVA followed by Sidak’s multiple comparisons test was performed for D, E and G. *P < 0.05; **P < 0.01. All analysis was done in triplicate from three independent cultures