Fig. 3.

Hypoxia inhibited the Wnt/β-Catenin pathway via the Akt/Gsk3β axis. A TOPFlash assays showed that hypoxia remarkably repressed the Wnt/β-Catenin pathway. B, C β-Catenin expression was repressed by hypoxia in AB2.2 mESCs undergoing differentiation. D Hypoxia repressed both the expression and nuclear localization of β-Catenin in differentiating AB2.2 mESCs. β-Catenin (green) was stained on differentiation day 4. Nuclei were stained with DPAI (blue). E Quantification was performed on the images of D using the ImageJ software. The intensity was calculated as the ratio of the β-Catenin positive area versus the whole area. The nuclear index was the ratio of β-Catenin positive nuclei versus total nuclei number. F, G p-Gsk3β, H–J p-Akt, and p-mTOR expression was significantly inhibited by hypoxia. K Schematic diagram of AB2.2 mESC differentiation treated with or without SC79, an Akt activator, under hypoxia. L–O p-Akt, p-Gsk3β, and β-Catenin were significantly upregulated with SC79 under hypoxia. P SC79 treatment upregulated the repression of mesendoderm marker expression (T, Eomes, Mesp1, and Gsc) under hypoxia. *, significant (P<0.05)