miR-29c-3p Attenuates β-Amyloid-Induced Neurotoxicity in Alzheimer’s Disease Through Regulating β-Site Amyloid Precursor Protein-Cleaving Enzyme 1

Abstract

The aberrantly expressed microRNAs (miRNAs) including miR-29c-3p have been reported in the brains of Alzheimer's disease (AD) patients in recent researches. Nevertheless, the functional role and underlying molecular mechanism of miR-29c-3p in AD pathogenesis are still not well elucidated. The purpose of this study was to examine whether miR-29c-3p regulated β-Ameyloid (Aβ)-induced neurotoxicity by targeting β-site amyloid precursor protein-cleaving enzyme 1 (BACE1). The expressions of miR 29c 3p and BACE1 mRNA and protein levels in Aβ-treated PC12 cellular AD model were examined by qRT-PCR and western blot analyses. Luciferase reporter assay verified the potential target of miR 29c 3p. Cell viability, apoptosis, and caspase-3 activity in PC12 cells were detected by the MTT assay, flow cytometry, and caspase-3 activity assay, respectively. Our results indicated that miR-29c-3p downregulation and BACE1 upregulation existed in the cellular AD model of PC12 cells. Moreover, miR-29c-3p directly inhibited BACE1 expression. miR-29c-3p overexpression and BACE1 knockdown strengthened Aβ-induced cell apoptosis, and caspase-3 activity in PC12 cells, which was partially eliminated by over-expression of BACE1. Conversely, BACE1 knockdown reversed the miR-29c-3p inhibition- mediated inhibitory effect on Aβ-induced cell toxicity, apoptosis, and caspase-3 activity in PC12 cells. Considering, miR-29c-3p attenuated Aβ-induced neurotoxicity through targeting BACE1 in an cellular AD model of PC12, providing a potential therapeutic target for AD treatment.