Knockdown of miR-429 Attenuates Aβ-Induced Neuronal Damage by Targeting SOX2 and BCL2 in Mouse Cortical Neurons

Accumulation of amyloid-β peptide (Aβ) and massive neuronal death due to apoptosis were the essential steps in the pathogenesis of Alzheimer's disease (AD). MiR-429 was reported to play an important role in the pathogenesis of AD. However, the detailed function and underlying molecular mechanism of miR-429 in the pathogenesis of AD remain elusive. Cortical neurons were stimulated with 20 µM of Aβ_25-35 for 24 h to construct AD model in vitro. qRT-PCR assay was used to detect the expression of miR-429, and qRT-PCR or western blot analysis were performed to assess the levels of Sex-determining region Y-box 2 (SOX2) and B cell lymphoma-2 protein (BCL2) at mRNA or proteins levels in the AD mouse model and Aβ-induced treated cortical neurons. Luciferase reporter assay and western blot analysis were used to confirm the potential targets of miR-429. CCK-8 assay, flow cytometry analysis, and caspase3 activity assay were used to measure cell viability, cell apoptosis capacity and caspase3 activity, respectively. MiR-429 was upregulated and SOX2 and BCL2 were downregulated in the AD mouse model and Aβ-induced mouse cortical neurons. MiR-429 knockdown attenuated Aβ-induced cytotoxicity in mouse cortical neurons. SOX2 and BCL2 were direct targets of miR-429. Moreover, anti-miR-429-mediated neuroprotective effect was abated by the restoration of SOX2 or BCL2 expression. Knockdown of miR-429 might attenuate Aβ-induced cytotoxicity by targeting SOX2 and BCL2 in mouse cortical neurons, providing a novel prospect in AD therapy.