Figure 2.

Insulin growth factor 1 (IGF-1) improved cell viability in hypoxic neural stem cells (NSCs). Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. (A) Hypoxic NSCs were cultured under different concentrations of IGF-1. (B) NSCs were divided into four groups: the Control, Hypoxia, Hypoxia+IGF-1, and Hypoxia+IGF-1+PPP groups. Data presented are the mean ±SD of three independent experiments. ** P<0.01; *** P<0.001. The significance marked at the top of the columns refers to comparison with the C group.