Effects of long non-coding RNA (SNHG1) on autophagy and growth of SH-SY5Y in a cell model of Parkinson’s disease

Abstract

Objective To investigate the effects of long non-coding RNA (SNHG1) on the autophagy and growth of human neuroblastoma cell line SH-SY5Y and their specific mechanism using a cell model of Parkinson's disease. Methods (1) After SH-SY5Y cells were cultured in vitro, the expression levels of autophagy-related proteins LC3-II/LC3-I and p62 were detected by Western Blotting at different time points and subjected to treatment with different dosages of 1-methyl-4-phenyl-pyridine (MPP+). The survival rate of SH-SY5Y was detected by MTT assay. (2) The expression of SNHG1 was detected by real-time quantitative PCR after SH-SY5Y treated with different concentrations of MPP+ for different time durations. (3) The expression of endogenous SNHG1 in SHSY5Y was down-regulated by specific siRNA; the expression levels of autophagy-related proteins LC3-II/LC3-I and p62 were detected by Western Blotting after MPP+ treatment while the survival rate of SH-SY5Y was detected by MTT. Moreover, SH-SY5Y cells were treated with autophagy late inhibitor bafilomycin A1 (Baf A1) and autophagy inducer to further clarify the role of SNHG1. (4) The expression of p27 was detected by Western blotting after treated with different concentrations of MPP+ for different time durations. In addition, after the expression of SNHG1 in SHSY5Y was down-regulated, the expression of p27 was detected by Western blotting. Results (1) The expression of LC3-II in SH-SY5Y was significantly increased in a dose- and time-dependent manner and the expression of p62 was significantly decreased (P<0.05). MTT results showed that MPP+ (2.5 mmol/L) significantly reduced the survival rate of SH-SY5Y (P<0.05). (2) Compared with the control group, the expression of SNHG1 was significantly increased in SH-SY5Y cells treated with MPP+ in a dose- and time-dependent manner (P<0.5). (3) When SNHG1 down-regulated, the expression of LC3-II induced by MPP+ was inhibited while the expression of p62 increased (P<0.05). In addition, when treated with Baf A1 at the same time, the expression of LC3-II was increased, suggesting that SNHG1 might mainly affect the autophagosome formation of SH-SY5Y. The survival rate of SH-SY5Y cells was significantly increased after SNHG1 was down-regulated, and the cell viability was further inhibited by SH-SY5Y treated with rapamycin, suggesting that SNHG1 inhibited the growth of SH-SY5Y cells through promoting the autophagy formation. (4) The expression of p27 was significantly increased in SH-SY5Y cells treated with MPP+ in a dose- and time-dependent manner (P<0.05). Down-regulation of SNHG1 expression inhibited the expression of p27, suggesting that SNHG1 might promote the autophagy and growth of SH-SY5Y cells through the p27 signal pathway. Conclusions SNHG1 can induce the autophagy of SH-SY5Y cells and promote death of the cells, which may be related to the regulation of p27 expression. Key words: Parkinson’s disease; Autophagy; SNHG1