Insulin-Like Growth Factors Promote Vasculogenesis in Embryonic Stem Cells
Figure 7
IGF1 increases HIF1α protein levels in differentiating embryoid bodies and inhibition of HIF1α with rapamycin decreases VEGF and VEGFR2 expression in embryoid bodies treated with IGF1.
A) HIF1αlevels increase significantly following treatment with IGF1. Rapamycin reduces protein levels when added to cell cultures prior to IGF1 stimulation. * denotes P<0.05 compared to conrol, ** denotes P<0.05 compared to +IGF B) Day 3 EB treated with IGF1 express significantly higher levels of VEGF and VEGFR2 compared with control (# denotes P<0.05 compared with control), which are significantly inhibited by treatment with HIF1α inhibitor rapamycin. (* denotes P<0.05 compared to IGF1 treatment). C) Proposed mechanism of IGF1 and IGF2 stimulated endothelial differentiation.