NEAT1_1 long non-coding RNA reduces the survival of primary neuronal cells under ER-stress

Abstract

NEAT1 long non-coding RNAs play an important role in the central nervous system (CNS) and are associated with a number of pathological conditions. Increased levels of NEAT1 in the brain have been observed in neurodegenerative and psychiatric diseases — the significance of such an increase is still poorly understood. Functionally, NEAT1 is associated with cellular stress pathways in the nervous system. The aim of the current study was to evaluate the effect of increased levels of the short isoform NEAT1_1 on survival of mice primary hippocampal cultures under ER-stress induced by MG132 proteasome inhibitor. Primary cultures were obtained from transgenic animals expressing human NEAT1_1. Cellular composition and apoptosis were assessed using immunocytochemical staining. The expression of apoptosis signaling pathway genes was analyzed by quantitative PCR with reverse transcription. No differences in cellular composition and morphological characteristics of neurons were observed in primary neuronal cultures obtained from transgenic animals as compared to wild type cultures. Induction of ER-stress resulted in a more significant increase in apoptotic death of cells including neurons in NEAT1_1 expressing cultures in comparison with the wild type cultures. ER-stress signaling pathway genes Atf4 and Ddit3 were less expressed in transgenic cultures under stress. Expression of Bcl2l2 and Mcl1 anti-apoptotic genes was reduced as well. Thus, high levels of NEAT1_1 in primary neuronal cultures increased apoptotic cell death under ER-stress.