LncRNA RPPH1 attenuates Aβ <sub>25-35</sub> -induced endoplasmic reticulum stress and apoptosis in SH-SY5Y cells via miR-326/PKM2
Ran Gu, Rui Liu, Lu Wang, Man Tang, Shirong Li, Xiao Hu
Abstract
Background The durative endoplasmic reticulum stress (ERS) and subsequent apoptosis contributes to the development and progression of Alzheimer’s disease (AD). MiR-326 can reduce pyruvate kinase M2 (PKM2) expression, leading to ERS. Whereas, lncRNA RPPH1 is able to increase dendritic spine density and protect hippocampal pyramidal neurons through targeting miR-326. Our study aims to investigate the regulation of lncRNA RPPH1 and miR-326/PKM2 on ERS and related apoptosis in AD.Methods SH-SY5Y cells treated with Aβ25-35 were selected as an in vitro AD model. RPPH1 and miR-326 overexpression and silencing cells were established by transforming vectors. The expression of RPPH1 and miR-326 were detected by qRT-PCR. MTT, flow cytometric, intracellular calcium assay and Western blot were used to test the functions of RPPH1 and miR-326 in SH-SY5Y cell proliferation, apoptosis and ERS. Dual-luciferase assay was used to detect the interaction among RPPH1, miR-326 and PKM2.Results RPPH1 overexpression enhanced the viability of SH-SY5Y cells, and attenuated the apoptosis of of SH-SY5Y cells. Moreover, RPPH1 overexpression down-regulated ER stress related proteins such as GRP78, CHOP and cleaved caspase-12. Mechanistically, RPPH1 directly targeted miR-326, thereby counteracting its inhibitory effect on PKM2 expression, contributing to attenuation of apoptosis and ERS induced by Aβ25-35.Conclusion Aβ25-35-induced ERS and apoptosis in SH-SY5Y cells can be attenuated by lncRNA RPPH1 through regulating miR-326/PKM2 axis. This study provided therapeutic options for AD patients.