Deficiency of NEAT1 prevented MPP(+)-induced inflammatory response, oxidative stress and apoptosis in dopaminergic SK-N-SH neuroblastoma cells via miR-1277-5p/ARHGAP26 axis.

Noncoding RNAs including long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) have been documented to play prominent role in neurodegenerative diseases including Parkinson's disease (PD). This study intended to investigate the role of lncRNA nuclear enriched assembly transcript 1 (NEAT1) in MPP+-induced PD model in dopaminergic neuronblastoma SK-N-SH cells, as well as its mechanism through sponging miRNA (miR)-1277-5p. Real-time PCR and western blotting revealed that NEAT1 and ARHGAP26 were upregulated, and miR-1277-5p was downregulated in MPP+-treated SK-N-SH cells in a certain of concentration- and time- dependent manner. MPP+ induced apoptosis in SK-N-SH cells, as evidenced by decreased cell viability and Bcl-2 expression, and elevated apoptosis rate and levels of Bax and cleaved caspase-3, which were examined by MTT assay, flow cytometry and western blotting. Moreover, commercial assay kits indicated that inflammatory response and oxidative stress were provoked in response to MPP+, due to promoted contents of interleukin (IL)-6, IL-1β, tumor necrosis factor-α, malondialdehyde, and lactate dehydrogenase, accompanied with suppressed superoxide dismutase and glutathione peroxidase levels. Notably, MPP+-induced apoptosis, inflammatory response and oxidative stress in SK-N-SH cells were mitigated by NEAT1 knockdown and/or miR-1277-5p overexpression. Moreover, silencing of miR-1277-5p could abrogate the suppression of NEAT1 deficiency on MPP+-induced cell injury. Similarly, upregulating miR-1277-5p-elicited neuroprotection in MPP+-induced SK-N-SH cells was reversed by ARHGAP26 restoration. Dual-luciferase reporter assay demonstrated a direct interaction between miR-1277-5p and NEAT1 or ARHGAP26. Collectively, NEAT1 upregulation might contribute to MPP+-induced neuron injury via NEAT1-miR-1277-5p-ARHGAP26 competing endogenous RNAs (ceRNAs) pathway.

Zhou S ，Zhang D ，Guo J ，Chen Z ，Chen Y ，Zhang J ... -  《-》

Long noncoding RNA NEAT1 knockdown inhibits MPP(+)-induced apoptosis, inflammation and cytotoxicity in SK-N-SH cells by regulating miR-212-5p/RAB3IP axis.

Some long non-coding RNAs (lncRNAs) have been suggested to play critical roles in Parkinson's disease (PD) pathogenesis, including nuclear enriched abundant transcript 1 (NEAT1). The purpose of this study was to further elucidate the molecular mechanism of NEAT1 in PD. The expression levels of NEAT1, miR-212-5p and RAB3A-interacting protein (RAB3IP) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were evaluated by Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis, respectively. Western blot analysis was applied to detect the protein expression of IL-1β, TNF-α and RAB3IP. The LDH activity, ROS generation and SOD activity were measured by Lactate LDH activity assay kit, ROS assay kit, and SOD activity assay kit, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to verify the relationship between miR-212-5p and NEAT1 or mRNA of RAB3IP. 1-methyl-4-phenylpyridinium ion (MPP+)-treated SK-N-SH cells were used as an in vitro model of PD. NEAT1 and RAB3IP were upregulated while miR-212-5p was downregulated in SK-N-SH cells treated with MPP+. NEAT1 knockdown or miR-212-5p overexpression inhibited MPP+-induced apoptosis, inflammation and cytotoxicity in SK-N-SH cells. Moreover, miR-212-5p was a direct target of NEAT1 and its downregulation reversed the eff ;ects caused by NEAT1 knockdown in MPP+-induced SK-N-SH cells. Furthermore, RAB3IP was a downstream target of miR-212-5p and its overexpression attenuated the effects of miR-212-5p restoration in MPP+-induced SK-N-SH cells. Besides, NEAT1 acted as a molecular sponge of miR-212-5p to regulate RAB3IP expression. NEAT1 knockdown suppressed MPP+-induced apoptosis, inflammation and cytotoxicity in SK-N-SH cells through regulating miR-212-5p and RAB3IP expression, providing a possible therapeutic strategy for PD patients.

Liu R ，Li F ，Zhao W 《-》

Long non-coding RNA UCA1 regulates MPP(+)-induced neuronal damage through the miR-671-5p/KPNA4 pathway in SK-N-SH cells.

Parkinson's disease (PD) is an age-related neurodegenerative disease. Long non-coding RNA urothelial carcinoma-associated 1 (UCA1) is involved in the pathogenesis of PD. However, the pathogenesis of PD regulated by UCA1 has not been fully explained. We used 1-Methyl-4-phenylpyridinium (MPP+)-induced SK-N-SH cells for functional analysis. Expression levels of UCA1, microRNA (miR)-671-5p, and KPNA4 (karyopherin subunit alpha 4) mRNA were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were analyzed using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) or flow cytometry assays. Some protein levels were measured by western blotting. The levels of pro-inflammatory cytokines were tested by ELISA (enzyme-linked immunosorbent assay). The levels of LDH (lactate dehydrogenase), MDA (malondialdehyde), and SOD (superoxide dismutase) were measured using corresponding kits. The relationship between UCA1 or KPNA4 and miR-671-5p was verified by dual-luciferase reporter assay and/or RNA immunoprecipitation (RIP) assay. MPP+ induced UCA1 expression in SK-N-SH cells in a concentration-dependent manner or time-dependent manner. UCA1 knockdown reduced MPP+-induced apoptosis, inflammation, and oxidative stress in SK-N-SH cells. MiR-671-5p was downregulated while KPNA4 was upregulated in MPP+-treated SK-N-SH cells. UCA1 sponged miR-671-5p to regulate KPNA4 expression. MiR-671-5p inhibition counteracted UCA1 knockdown-mediated influence on apoptosis, inflammation, and oxidative stress of MPP+-induced SK-N-SH cells. KPNA4 overexpression offset the inhibitory influence of miR-671-5p mimic on apoptosis, inflammation, and oxidative stress of MPP+-treated SK-N-SH cells. UCA1 inhibition reduced MPP+-induced neuronal damage through the miR-671-5p/KPNA4 pathway in SK-N-SH cells, providing a novel mechanism to understand the pathogenesis of PD.

Hao Z ，Dang W ，Zhu Q ，Xu J ... -  《-》

LncRNA JHDM1D-AS1 Suppresses MPP + -Induced Neuronal Injury in Parkinson's Disease via miR-134-5p/PIK3R3 Axis.

Parkinson's disease (PD) is a multi-factorial neurodegenerative disease. Long noncoding RNAs (lncRNAs) have been revealed to be involved in the process of PD. Herein, this study aimed to investigate the potential function and mechanism of JHDM1D-AS1 (JHDM1D antisense 1) in PD process. 1-Methyl-4-phenylpyridinium (MPP +)-induced SK-N-SH cells were used to conduct expression and function analyses. Levels of genes and proteins were examined using real-time reverse transcription PCR (RT-qPCR) and Western blot. Cell viability and apoptosis were determined using CCK-8 assay, flow cytometry, and Western blot, respectively. ELISA analysis was performed for the detection of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. The contents of lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured using commercial kits. The direct interactions between miR-134-5p and PIK3R3 (Phosphoinositide-3-Kinase Regulatory Subunit 3) or JHDM1D-AS1 were verified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. JHDM1D-AS1 expression was decreased by MPP + in SK-N-SH cells in a dose- or time-dependent manner. Functionally, JHDM1D-AS1 overexpression attenuated MPP + -evoked neuronal apoptosis, inflammation, and oxidative stress. Mechanistically, JHDM1D-AS1 competitively bound to miR-134-5p to upregulate the expression of its target PIK3R3. Rescue experiments suggested that miR-134-5p upregulation reversed the inhibitory effects of JHDM1D-AS1 on MPP + -induced neuronal injury. Moreover, inhibition of miR-134-5p protected neurons against MPP + -induced neuronal apoptosis, inflammation, and oxidative stress, which were abolished by PIK3R3 silencing. JHDM1D-AS1 protected against MPP + -induced neuron injury via miR-134-5p/PIK3R3 axis, suggesting the potential involvement of this axis in PD process.

Wang C ，Zhang H ，Li J 《-》

Long noncoding RNA SRY-box transcription factor 2 overlapping transcript participates in Parkinson's disease by regulating the microRNA-942-5p/nuclear apoptosis-inducing factor 1 axis.

Guo Y ，Liu Y ，Wang H ，Liu P ... -  《-》