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SNHG12 inhibits oxygen-glucose deprivation-induced neuronal apoptosis via the miR-181a-5p/NEGR1 axis

ABSTRACT: Emerging evidence has indicated that long non-coding RNAs (lncRNAs) are closely associated with the pathogenesis of ischemic stroke. It has been reported that small nucleolar RNA host gene 12 (SNHG12) serves a critical role in ischemic stroke by acting as a competitive endogenous RNA (ceRNA). SNHG12 competes with various microRNAs (miRs) to regulate RNA transcription of specific targets. However, the effect of SNHG12 on oxygen-glucose deprivation (OGD)-induced neuronal apoptosis has rarely been reported. The present study demonstrated that SNHG12 expression was downregulated in OGD-injured SH-SY5Y cells. Furthermore, miR-181a-5p was reported as a target of SNHG12 and was negatively regulated by SNHG12. Moreover, NEGR1 was a target of miR-181a-5p, which functions as a negative regulator of NEGR1 in OGD-induced neuronal apoptosis. In summary, the results strongly confirmed the hypothesis that SNHG12 functions as a ceRNA for miR-181a-5p and regulates the expression of NEGR1 thus inhibiting OGD-induced apoptosis of SH-SY5Y cells. Neuronal apoptosis aggravates brain damage during ischemic stroke, indicating that the activation of SNHG12 and NEGR1 expression and inhibition of miR-181a-5p may be a novel strategy for the clinical treatment of ischemic stroke.

SUBMITTER: Yan Y

PROVIDER: S-EPMC7533499 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Project description:Neuronal apoptosis is a major pathological hallmark of the neonatal hypoxic-ischemic brain damage (HIBD); however, the role of miR-7a-2-3p in the regulation of HIBD remains unknown. The purpose of this study was to explore the possible roles of miR-7a-2-3p in brain injury using a hypoxia-ischemia model in rats and oxygen-glucose deprivation (OGD) model in vitro. Firstly, we established the hypoxia-ischemia (HI) model and verified the model using Zea Longa scores and MRI in rats. Next, the changes of miR-7a-2-3p were screened in the ischemic cortex of neonatal rats by qRT-PCR at 12, 48, and 96 h after HIBD. We have found that the expression of miR-7a-2-3p in the HI rats decreased significantly, compared with the sham group (P < 0.01). Then, we established the OGD model in PC12 cells, SH-SY5Y cells and primary cortical neurons in vitro and qRT-PCR was used to confirm the changes of miR-7a-2-3p in these cells after the OGD. In order to determine the function of miR-7a-2-3p, PC12 cells, SH-SY5Y cells and rat primary cortical neurons were randomly divided into normal, OGD, mimic negative control (mimic-NC) and miR-7a-2-3p groups. Then, Tuj1+ (neuronal marker) staining, TUNEL assay (to detect apoptotic cells) and MTT assay (to investigate cell viability) were performed. We have found that the number of PC12 cells, SH-SY5Y cells and cortical neurons in the miR-7a-2-3p groups increased significantly (P < 0.01) in comparison to the OGD groups. The survival of cortical neurons in the miR-7a-2-3p group was improved markedly (P < 0.01), while the apoptosis of neurons in the miR-7a-2-3p group was significantly decreased (P < 0.01), compared with the normal group. Lastly, we investigated the target genes of miR-7a-2-3p by using the prediction databases (miRDB, TargetScan, miRWalk, and miRmap) and verified the target genes with qRT-PCR in the HI rats. Bioinformatics prediction showed that Vimentin (VIM), pleiomorphic adenoma gene 1(PLAG1), dual specificity phosphatase 10 (DUSP10), NAD(P)H dehydrogenase, quinone 1 (NQO1) and tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) might be the targets of miR-7a-2-3p and the qRT-PCR confirmed that VIM increased in the HI rats (P < 0.01). In conclusion, miR-7a-2-3p plays a crucial role in the hypoxic-ischemic injury, and is associated with regulation of VIM.

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SNHG12 inhibits oxygen-glucose deprivation-induced neuronal apoptosis via the miR-181a-5p/NEGR1 axis

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