Hypoxia stimulates neural stem cell proliferation by increasing HIF ‑1α expression and activating Wnt/β-catenin signaling.

Hypoxia stimulates neural stem cell proliferation by increasing HIF‑1α expression and activating Wnt/β-catenin signaling. Cell Mol Biol (Noisy-le-grand). 2017 Aug 15;63(7):12-19 Authors: Qi C, Zhang J, Chen X, Wan J, Wang J, Zhang P, Liu Y Abstract Evidence indicates that after brain injury, neurogenesis is enhanced in regions such as hippocampus, striatum, and cortex. To study the role of hypoxia-inducible factor-1 (HIF‑1α) and Wnt signaling in cerebral ischemia/hypoxia-induced proliferation of neural stem cells (NSCs), we investigated the proliferation of NSCs, expression of HIF‑1α, and activation of Wnt signaling under conditions of pathologic hypoxia in vitro. NSCs were isolated from 30-day-old Sprague-Dawley rats and subjected to 0.3% oxygen in a microaerophilic incubation system. Cell proliferation was evaluated by measuring the diameter of neurospheres and by bromodeoxyuridine incorporation assays. Real-time quantitative PCR and Western blotting were used to detect mRNA and protein levels of HIF-1α, β-catenin, and cyclin D1 in the NSCs. The results showed that hypoxia increased NSC proliferation and the levels of HIF-1α, β‑catenin, and cyclin D1 (p < 0.05). Blockade of the Wnt signaling pathway decreased hypoxia-induced NSC proliferation, whereas activation of this pathway increased hypoxia-induced NSC proliferation (p < 0.05). Knockdown of HIF-1α with HIF-1α siRNA decreased β‑catenin nuclear...
Source: Cellular and Molecular Biology - Category: Molecular Biology Tags: Cell Mol Biol (Noisy-le-grand) Source Type: research