Knockdown Of NEAT1 Research Articles

Inhibition of long non-coding RNA NEAT1 suppressed the epithelial mesenchymal transition through the miR-204-5p/Six1 axis in asthma.

Asthma, a prevalent chronic respiratory condition, is characterized by airway remodeling. Long non-coding RNA (lncRNA) NEAT1 has been demonstrated to participate in airway fibrosis. Furthermore, the miR-204-5p/Six1 axis significantly influences epithelial mesenchymal transition (EMT). However, the function of NEAT1/miR-204-5p/Six1 in asthmatic EMT remains unclear. This study intends to elucidate the function of NEAT1/miR-204-5p/Six1 axis in asthmatic EMT. TGF-β1 was used to induce the EMT model in BEAS-2B cells. Immunofluorescence and western blot were executed to verify the establishment of the EMT model. NEAT1, miR-204-5p, and Six1 expression levels were evaluated using RT-qPCR. The role of NEAT1 in EMT in vitro was explored by CCK8 assays and flow cytometry. The luciferase reporter assay was performed to validate the interaction between NEAT1 and miR-204-5p/Six1. NEAT1 expression was increased during EMT. Functional experiments showed that the knockdown of NEAT1 suppressed cell proliferation and promoted cell apoptosis in vitro. Furthermore, inhibition of NEAT1 decreased the expression of N-cadherin, vimentin, and α-SMA and increased the expression of E-cadherin. Mechanistically, NEAT1 was identified as a sponge for miR-204-5p, and Six1 was found to be a direct target of miR-204-5p. Down-regulation of NEAT1 reduced the Six1 expression via targeting miR-204-5p to inhibit the process of EMT in asthma. This study may provide new insight to reveal the underlying mechanisms of asthma.

Long non-coding RNA NEAT1 induced by BHLHE40 activates Wnt/β-catenin signaling and potentiates colorectal cancer progression

BackgroundNuclear-enriched abundant transcript 1 (NEAT1), a long noncoding RNA (lncRNA), has been implicated in the colorectal cancer (CRC) progression. However, its upstream mechanism has not been well studied. In the present study, the functions and mechanisms of NEAT1 in CRC were investigated.MethodsThe NEAT1 expression in CRC tissues and CRC cells was analyzed by RT-qPCR. The genes co-expressed with NEAT1 in CRC were obtained from UALCAN, which were intersected with the transcription factors targeting NEAT1 from hTFtarget. Dual-luciferase assay, RT-qPCR, and ChIP were conducted to analyze the transcriptional regulatory relationship between BHLHE40 and NEAT1. LoVo and HCT-15 cells knocking down BHLHE40 and overexpressing NEAT1 were subjected to MTT, Transwell, Western blot, and flow cytometry to examine the malignant aggressiveness of CRC cells. The effects of knocking down BHLHE40 and overexpressing NEAT1 on tumor and lung metastasis were investigated in mice using HE and immunohistochemical analyses.ResultsNEAT1 and BHLHE40 were significantly overexpressed in CRC tissues and cells. BHLHE40 has a binding relationship with the NEAT1 promoter. Knockdown of BHLHE40 resulted in a reverted malignant phenotype in vitro and slowed tumor growth and metastasis dissemination in vivo, which were reversed by NEAT1 overexpression. Overexpression of BHLHE40 increased Wnt/β-catenin pathway activity, but knockdown of NEAT1 decreased Wnt/β-catenin pathway activity.ConclusionsBHLHE40 mediates the transcriptional activation of NEAT1, which activates the Wnt/β-catenin pathway and promotes the CRC progression.

Long non-coding RNA NEAT1 exacerbates NLRP3-mediated pyroptosis in allergic rhinitis through regulating the PTBP1/FOXP1 cascade

BackgroundAllergic Rhinitis (AR) is a prevalent chronic non-infectious inflammation affecting the nasal mucosa. NLRP3-mediated pyroptosis of epithelial cells plays a pivotal role in AR pathogenesis. Herein, we evaluated the impact of the long non-coding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) on NLR family pyrin domain containing 3 (NLRP3)-mediated pyroptosis in AR. MethodsNasal inflammation levels in ovalbumin (OVA)-induced AR mice were assessed using HE staining, and NLRP3 expression was evaluated through immunohistochemistry. ELISA was utilized to detect OVA-specific IgE, IL-6, IL-5, and inflammatory cytokines (IL-1β, IL-18). Human nasal epithelial cells (HNEpCs) stimulated with IL4/IL13 were used to analyze the mRNA and protein levels of associated genes utilizing RT-qPCR and western blot, respectively. Cell viability and pyroptosis were assessed by CCK-8 and flow cytometry. The targeting relationship between NEAT1, PTBP1 and FOXP1 were analyzed by RIP and RNA pull down assays. FISH and IF analysis were performed to assess the co-localization of NEAT1 and PTBP1. ResultsIn both the AR mouse and cellular models, increased levels of NEAT1, PTBP1 and FOXP1 were observed. AR mice exhibited elevated inflammatory infiltration and pyroptosis, evidenced by enhanced expressions of OVA-specific IgE, IL-6, and IL-5, NLRP3, Cleaved-caspase 1, GSDMD-N, IL-1β and IL-18. Functional assays revealed that knockdown of PTBP1 or NEAT1 inhibited pyroptosis while promoting the proliferation of IL4/IL13-treated HNEpCs. Mechanistically, NEAT1 directly interacted with PTBP1, thereby maintaining FOXP1 mRNA stability. Rescue assays demonstrated that FOXP1 upregulation reversed the inhibitory effects of silencing NEAT1 or PTBP1 on IL4/IL13-stimulated pyroptosis activation in HNEpCs. ConclusionNEAT1 acts as a RNA scaffold for PTBP1, activating the PTBP1/FOXP1 signaling cascade, subsequently triggering NLRP3-mediated pyroptosis in HNEpCs, and ultimately promoting AR progression. These findings highlight some new insights into the pathogenesis of AR.

AAV mediated repression of Neat1 lncRNA combined with F8 gene augmentation mitigates pathological mediators of joint disease in haemophilia.

Haemophilic arthropathy (HA), a common comorbidity in haemophilic patients leads to joint pain, deformity and reduced quality of life. We have recently demonstrated that a long non-coding RNA, Neat1 as a primary regulator of matrix metalloproteinase (MMP) 3 and MMP13 activity, and its induction in the target joint has a deteriorating effect on articular cartilage. In the present study, we administered an Adeno-associated virus (AAV) 5 vector carrying an short hairpin (sh)RNA to Neat1 via intra-articular injection alone or in conjunction with systemic administration of a capsid-modified AAV8 (K31Q) vector carrying F8 gene (F8-BDD-V3) to study its impact on HA. AAV8K31Q-F8 vector administration at low dose, led to an increase in FVIII activity (16%-28%) in treated mice. We further observed a significant knockdown of Neat1 (~40 fold vs. untreated injured joint, p = 0.005) in joint tissue of treated mice and a downregulation of chondrodegenerative enzymes, MMP3, MMP13 and the inflammatory mediator- cPLA2, in mice receiving combination therapy. These data demonstrate that AAV mediated Neat1 knockdown in combination with F8 gene augmentation can potentially impact mediators of haemophilic joint disease.

Long Non-coding RNA NEAT1 , NOD-Like Receptor Family Protein 3 Inflammasome, and Acute Kidney Injury.

Acute kidney injury (AKI) is common in hospitalized patients and is associated with high mortality. Inflammation plays a key role in the pathophysiology of AKI. Long non-coding RNAs (lncRNAs) are increasingly recognized as regulators of the inflammatory and immune response, but its role in AKI remains unclear. We explored the role of lncRNA Neat1 in (1) a cross-sectional and a longitudinal cohort of AKI in human; (2) three murine models of septic and aseptic AKI and (3) cultured C1.1 mouse kidney tubular cells. In human, hospitalized patients with AKI (n=66) demonstrated significantly increased lncRNA Neat1 levels in urinary sediment cells and buffy coat versus control participants (n=152) from a primary care clinic; and among 6 kidney transplant recipients, Neat1 levels were highest immediately after transplant surgery followed by a prompt decline to normal levels in parallel with recovery of kidney function. In mice with AKI induced by sepsis (via LPS injection or cecal ligation and puncture) and renal ischemia-reperfusion, kidney tubular Neat1 was increased versus sham-operated mice. Knockdown of Neat1 in the kidney using short hairpin RNA preserved kidney function, suppressed overexpression of the AKI biomarker NGAL, leukocyte infiltration and both intrarenal and systemic inflammatory cytokines IL-6, CCL-2 and IL-1β. In LPS-treated C1.1 cells, Neat1 was overexpressed via TLR4/NF-κB signaling, and translocated from the cell nucleus into the cytoplasm where it promoted activation of NLRP3 inflammasomes via binding with the scaffold protein Rack1. Silencing Neat1 ameliorated LPS-induced cell inflammation, whereas its overexpression upregulated IL-6 and CCL-2 expression even without LPS stimulation. Our findings demonstrate a pathogenic role of Neat1 induction in human and mice during AKI with alleviation of kidney injury in 3 experimental models of septic and aseptic AKI after knockdown of Neat1. LPS/TLR4-induced Neat1 overexpression in tubular epithelial cells increases the inflammatory response by binding with the scaffold protein, Rack1, to activate NLRP3 inflammasomes.

Retraction: Knockdown of NEAT1 restrained the malignant progression of glioma stem cells by activating microRNA let-7e

Retraction: Knockdown of NEAT1 restrained the malignant progression of glioma stem cells by activating microRNA <i>let-7e</i>

Knockdown of lncRNA NEAT1 suppresses streptococcus pneumoniae-induced ferroptosis in alveolar epithelial cells by regulating the Nrf2-GPX4 pathway

ObjectivesStreptococcus pneumoniae (SP) is a major cause of community-acquired pneumonia. Ferroptosis pitches in pneumonia. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) regulates ferroptosis in various cells. Therefore, this study probed the mechanism of lncRNA NEAT1 on SP-induced ferroptosis in AECs. MethodsSerum lncRNA NEAT1 level in 36 streptococcus pneumonia patients were retrospectively detected, with its correlations with inflammatory factor (TNF-α/IL-1β/IL-6) levels analyzed. Human pulmonary alveolar epithelial cells (HPAEpiC) were transfected with sh-NEAT1 and induced by SP. Cell viability was evaluated by CCK-8. Lactate dehydrogenase (LDH) activity was assessed. Iron content, and levels of TNF-α/IL-1β/IL-6/IL-10/lncRNA NEAT1/lipid peroxidation products [malondialdehyde (MDA)/glutathione (GSH)/reactive oxygen species/(ROS)]/ferroptosis-related proteins [Cyclooxgenase 2 (COX2)/recombinant solute carrier family 7 member 11 (SLC7A11)/total nuclear factor erythroid 2-related factor 2 (Nrf2)/cytoplasmic Nrf2 (C-Nrf2)/nuclear Nrf2 (N-Nrf2)/GPX4)] were determined by kit/ELISA/RT-qPCR/kits/Western blot. Nrf2 nuclear translocation was detected by immunofluorescence assay. On top of lncRNA NEAT1 knockdown, SP-induced HPAEpiC were treated with ML385. ResultsSerum lncRNA NEAT1 level was elevated in streptococcus pneumonia patients, and were positively interrelated with TNF-α/IL-1β/IL-6 levels. SP promoted cell HPAEpiC injury and inflammatory response, and up-regulated lncRNA NEAT1 level. LncRNA NEAT1 knockdown suppressed HPAEpiC injury/inflammatory response (reduced LDH activity and TNF-α/IL-1β/IL-6 levels, elevated IL-10) and suppressed ferroptosis (decreased iron/MDA/ROS contents and COX2 level, increased GSH/SLC7A11), facilitated Nrf2 nuclear translocation, and up-regulated GPX4. Nrf2-GPX4 pathway inhibition annulled NEAT1 knockdown-mediated improvement on SP-induced HPAEpiC ferroptosis/injury/inflammatory response. ConclusionsLncRNA NEAT1 knockdown suppressed SP-induced HPAEpiC ferroptosis by activating Nrf2-GPX4 pathway, thereby alleviating cell injury and inflammatory response.

Targeting NEAT1 Affects the Sensitivity to PARPi in Serous Ovarian Cancer by Regulating the Homologous Recombination Repair Pathway.

Objective: Patients initially sensitive to PARPi (PARP inhibitor) regain resistance because of homologous recombination (HR) restoration, although PARPi has a synthetic lethality effect on serous ovarian cancer cells with BRCA1/2 mutations. This study aimed to investigate the role of NEAT1 in HR function and whether targeting NEAT1 in serous ovarian cancer cells could increase PARPi sensitivity. Methods: Ovarian cancer patients' clinical information and the expression of NEAT1 were collected from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Ovarian cancer (OC) cells HeyA8 and SKOV3 were silenced by transfecting NEAT1 ASO. QRT-PCR confirmed the mRNA expression of RAD51, FOXM1, NEAT1_1 and NEAT1_2. We assessed the expression of RAD51, FOXM1, and γ-H2AX by Western blotting and Immunofluorescence. Comet Assays were used to detect DNA double-strand damage levels. In OC cells transfected with NEAT1 ASO or co-transfected overexpression RAD51/empty vector and si-NEAT1/si-ctrl, the sensitivity to Olaparib was determined using CCK8 assay. The Kaplan-Meier survival curves assessed the prognostic and predictive roles of NEAT1 in OC. Results: NEAT1 was an independent prognostic marker of ovarian cancer. NEAT1 knockdown reduced the expression of NEAT1_1, NEAT1_2, RAD51, and FOXM1 and increased the expression of γ-H2AX. In addition, Olaparib increased the expression of RAD51, representing HR repair efficiency, which was inhibited by NEAT1 knockdown. Moreover, the knockdown of NEAT1 increased the DNA damage caused by Olaparib, demonstrated by increased nuclear γ-H2AX foci, DNA in the tail, and expression of γ-H2AX. NEAT1 knockdown sensitized ovarian cancer cells to Olaparib by targeting RAD51-HR. NEAT1 expression could predict response to chemotherapy for ovarian cancer. Conclusions: NEAT1 knockdown inhibited HR capacity and increased DNA damage caused by Olaparib in serous ovarian cancer cells, making them more sensitive to Olaparib and providing a crucial therapeutic advantage of increasing sensitivity to Olaparib.

Long Noncoding RNA NEAT1 Regulates Acute Graft-Versus-Host Disease By Promoting Macrophage M1 Polarization through JNK Pathway

Introduction Acute graft-versus-host disease (aGVHD) is a complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). The function of macrophages in aGVHD is a hot point in current research. Long noncoding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) is closely related to immune-related diseases and affects the function of macrophages. However, the role of LncRNA NEAT1 in aGVHD is unclear in current study. Methods Peripheral blood mononuclear cells (PBMCs were collected from the patients with or without aGVHD after allo-HSCT. The expression of lncRNA NEAT1 in PBMCs was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The diagnostic value of lncRNA NEAT1 in aGVHD was analyzed by receiver operating characteristic curve (ROC) and area under correlation curve (AUC). We transfected RAW264.7 cells and bone marrow-derived macrophages (BMDM) with NEAT1 lentiviral vector or NEAT1 small interfering RNA to change the expression level of NEAT1. The function of NEAT1 and its effect on JNK pathway were analyzed by flow cytometry, qRT-PCR, western blotting and ELISA. Finally, aGVHD mouse model was constructed to evaluate the function of JNK inhibitors in aGVHD. Results Compared with non-aGVHD patients, LncRNA NEAT1 was significantly up-regulated in PBMCs of aGVHD patients. ROC and AUC analysis confirmed that the expression level of lncRNA NEAT1 was correlated with the occurrence of aGVHD, which may have certain diagnostic value in aGVHD. We found the expressions of NEAT1 in BMDM and RAW264.7 were remarkably increased after being stimulated with lipopolysaccharide (100ng/ml). The overexpression of lncRNA NEAT1 in RAW264.7 could significantly up-regulate the expression level of iNOS, and induce the differentiation into M1 type. Knockdown of lncRNA NEAT1 in BMDM could significantly down-regulate the gene expressions (iNOS and NLRP3), reduce the protein levels (iNOS, NLRP3 and p-JNK), decrease the proportion of M1 macrophages and inflammatory cytokines secretion (TNF-α and IL-1β), and inhibit the JNK pathway. We found that JNK inhibitor could perform the same function as knocking down lncRNA NEAT1 in BMDM. In addition, JNK inhibitor could improve the survival and pathology, decrease the inflammatory cytokines secretion (TNF-α and IL-1β), and reduce the infiltration of M1 macrophages into the target organs in aGVHD mouse model. Conclusions Our results showed that lncRNA NEAT1 may regulate the M1 polarization of macrophages and the secretion of inflammatory cytokines by regulating the JNK pathway. JNK inhibitor may reduce the inflammation in aGVHD mouse models by blocking the function of NEAT1 in macrophages. This study provides a promising therapeutic target for aGVHD.

ZNF143 inhibits hepatocyte mitophagy and promotes non-alcoholic fatty liver disease by targeting increased lncRNA NEAT1 expression to activate ROCK2 pathway

ABSTRACT Background: Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disorders worldwide. The mitophagy is suggested to be repressed in NAFLD, but the mechanism remains to be elucidated. Methods: NAFLD cell and mouse models were established by treating with free fatty acid (FFA) and feeding a high fat diet (HFD), respectively. QRT-PCR, Western blotting, or IHC measured the expression of ZNF143, lncRNA NEAT1, ROCK2, and lipid formation/mitophagy-related proteins. Cell viability and mitophagy were evaluated by MTT and immunofluorescence. The chloroform-methanol extraction method measured triglyceride and total cholesterol levels. ELISA detected ALT and AST levels. The interactions among ZNF143, lncRNA NEAT1 and SND1 were analysed by ChIP, dual-luciferase reporter, pull-down, and RIP. The lipid droplets were determined by Oil-red O and HE staining. Results: ZNF143 and lncRNA NEAT1 were upregulated in hepatic cells treated with FFA (p < 0.01 and p < 0.001). Knockdown of ZNF143 or lncRNA NEAT1 inhibited lipid droplets formation, while promoting mitophagy (p < 0.01 and p < 0.001). ZNF143 promoted lncRNA NEAT1 transcriptional expression through binding to its promoter. LncRNA NEAT1 increased ROCK2 mRNA stability by targeting SND1. LncRNA NEAT1 or ROCK2 overexpression reversed the effect of ZNF143 or lncRNA NEAT1 knockdown on hepatic steatosis and mitophagy (p < 0.01 and p < 0.001). ZNF143 or lncRNA NEAT1 knockdown inhibited HFD-induced steatosis and promoted mitophagy in vivo (p < 0.01 and p < 0.001). Conclusion: The upregulation of lncRNA NEAT1 caused by ZNF143 promoted NAFLD through inhibiting mitophagy via activating ROCK2 pathway by targeting SND1, providing potential targets for NAFLD therapy.

NEAT1_2 and DAZAP1, Paraspeckle Components, Interact with PXR to Negatively Regulate CYP3A4 Induction.

Human pregnane X receptor (PXR) is a major nuclear receptor that upregulates the expression of drug-metabolizing enzymes such as CYP3A4. In our recent study, it was revealed that PXR interacts with DAZ-associated protein 1 (DAZAP1), which is an essential component of the paraspeckle, a membraneless nuclear body, and the interaction was disassociated by rifampicin, a ligand of PXR. The purpose of this study was to clarify the roles of paraspeckles in PXR-mediated transcriptional regulation. Immunoprecipitation assays using PXR-overexpressing HepG2 (ShP51) cells revealed that PXR interacts with not only DAZAP1 but also NEAT1_2, a long noncoding RNA included in the paraspeckle, and that the interaction between PXR and NEAT1_2 was disassociated by rifampicin. These results suggest that PXR is trapped in paraspeckles and that the activation of PXR by its ligands facilitates its disassociation from paraspeckles. Induction of CYP3A4 by rifampicin was significantly enhanced by the knockdown of NEAT1_2 or DAZAP1 in ShP51 cells and their parental HepG2 cells. A luciferase assay using a plasmid containing the PXR response elements of CYP3A4 revealed that the increased CYP3A4 induction by siNEAT1_2 or siDAZAP1 was due to the increased transactivation by PXR. These results suggest that paraspeckles play a role in trapping nuclear PXR in the absence of the ligand to negatively regulate transactivation of its downstream gene. Collectively, this is the first study to demonstrate that the paraspeckle components NEAT1_2 and DAZAP1 negatively regulate CYP3A4 induction by PXR. SIGNIFICANCE STATEMENT: This study revealed that PXR interacts with paraspeckle components NEAT1_2 and DAZAP1 to suppress CYP3A4 induction by PXR, and the interaction is dissociated by PXR ligands. This finding provides a novel concept that paraspeckles formed by liquid-liquid phase separation potentially affect drug metabolism via negative regulation of PXR function.

Long Non-Coding RNA Nuclear Paraspeckle Assembly Transcript 1: A Regulator of Trophoblast Cells in the Progression of Gestational Diabetes Mellitus

The potential function of NEAT1 in the progression of Gestational diabetes mellitus (GDM) and the molecular mechanisms are explored. NEAT1 levels in multiple types of cell lines and placental tissues collected from healthy, GDM and preeclampsia pregnancies were detected by quantitative real-time polymerase chain reaction (qRT-PCR). After intervening NEAT1 level in HTR-8/SVneo cells, proliferative, migratory and apoptotic potentials were examined by cell counting kit-8 (CCK-8), 5-Ethynyl-2′-deoxyuridine (EdU), transwell assay and flow cytometry. The regulatory effect of NEAT1 on the transcriptional activity of NSD1 was predicted by bioinformatic analysis and further confirmed by dual-luciferase reporter assay. In addition, histone modifications of NEAT1 on NSD1 transcription were examined by chromatin immunoprecipitation (ChIP). NEAT1 was upregulated in placental tissues collected from GDM patients. Overexpression of NEAT1 stimulated proliferative and migratory potentials, but inhibited apoptosis in HTR-8/SVneo cells. Knockdown of NEAT1 had the opposite outcomes. NEAT1 was able to regulate the transcriptional activity of NSD1 through histone modifications on H3K27Me3 and H3K27Cro. NEAT1 is upregulated in GDM cases, which triggers proliferative and migratory potentials in trophoblast cells mainly through regulating transcriptional activity of NSD1 via histone modification.

Exosomal lncRNA NEAT1 induces paclitaxel resistance in breast cancer cells and promotes cell migration by targeting miR-133b

The lncRNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) has been associated with the development, metastasis and drug resistance of breast cancer (BC). However, the mechanisms underlying NEAT1-induced paclitaxel resistance in the microenvironment of BC remain unclear. In this study, NEAT1 expression was found to be high in paclitaxel-resistant BC cells (SKBR3/PR cells) and exosomes derived from these cells. NEAT1 promoted the migration of BC cells and their resistance to paclitaxel, whereas its downregulation reduced the drug resistance. In addition, downregulation of NEAT1 decreased the migration and proliferation of BC cells by inhibiting the expression of CXCL12 by reducing the adsorption of miR-133b. Furthermore, inhibition of miR-133b reversed the interference of NEAT1 and CXCL12 in paclitaxel resistance, migration and proliferation of BC cells. Knockdown of NEAT1 in a xenograft-bearing mouse model remarkably inhibited cancer progression and improved the response to paclitaxel. Altogether, this study revealed that SKBR3/PR cell-derived exosomal lncRNA NEAT1 can induce paclitaxel resistance and cell migration and growth in the tumour microenvironment of BC and may serve as a new target for the clinical treatment of BC.

Lncrna NEAT1 Regulates Th1/Th2 in Pediatric Asthma by Targeting MicroRNA-217/GATA3.

The imbalance of immune response between helper Th1 and Th2 cells is the direct cause of asthma. It was closely related to abnormal expression of lncRNAs. However, whether lncRNAs can regulate Th1/Th2 balance in pediatric asthma remains to be investigated. Peripheral blood samples were collected from children with asthma and normal volunteers at the Children's Hospital of Shaanxi Provincial People's Hospital (Xi'an, China) in 2020. The qRT-PCR was used to detect the expression of lncRNA NEAT1, miR-217 and GATA3 in peripheral blood samples. The effects of lncRNA NEAT1, miR-217, and GATA3 on CD4+T cell population were detected in vitro. Meanwhile, the regulatory effect of lncRNA NEAT1/miR-217/GATA3 was evaluated through the dual luciferase report assay, functional assays and animal experiments. We investigated that lncRNA NEAT1 and GATA3 was significantly up-regulated in CD4+T cells in peripheral blood of children with asthma (P<0.001). Knockdown of lncRNA NEAT1 or GATA3 significantly reduced Th2-related cytokines (P<0.05), but had no effect on Th1 cells. Importantly, the interactions of lncRNA NEAT1 with miR-217 and miR-217 with GATA3 were confirmed by dual luciferase report assay. Meanwhile, functional assays and animal experiments demonstrated that lncRNA NEAT1 regulated GATA3 expression through sponge miR-217, thereby regulating Th1/Th2 balance in CD4+T cells in pediatric asthma. lncRNA NEAT1/miR-217/GATA3 axis may reveal the immunological mechanism of pediatric asthma, which has potential clinical application value in the future.

Knockdown of NEAT1 restricts dengue virus replication by augmenting interferon alpha-inducible protein 27 via the RIG-I pathway.

The lncRNA NEAT1 plays a vital role in mitochondrial function and antiviral response. We have previously identified NEAT1 as dysregulated lncRNAs and found an inverse correlation with interferon alpha-inducible protein 27 (IFI27) expression associated with developing dengue severity. However, the role of NEAT1 in dengue virus (DV) infection remains elusive. Here, we undertook a study to evaluate the functional consequences of NEAT1 and IFI27 modulation on antiviral response and viral replication in dengue infection. We observed that the knockdown of NEAT1 augmented IFI27 expression and antiviral response via the RIG-I pathway. Increased antiviral response leads to a decrease in dengue viral replication. Further study suggested that the knockdown of IFI27 augmented expression of the activating transcription factor 3 (ATF3), a negative regulator of antiviral response, and increased dengue virus replication suggesting an important role played by IFI27 in mediating antiviral response. RNA sequencing study confirmed several mitochondrial genes significantly altered upon knockdown of NEAT1 in DV-infected cells. We further verified the effect of NEAT1 knockdown on mitochondrial functions. We observed a reduced level of phospho-DRP1(S616) expression along with elongated mitochondria in DV2-infected cells. Further, NEAT1 knockdown or ectopic expression of IFI27 increased mitochondrial ROS production and cell death via activation of caspase 3. Our study points to the crucial role of NEAT1 and IFI27 in mediating antiviral response and mitochondrial dysfunction in dengue infection.

Up-regulation of lncRNA NEAT1 in cerebral ischemic stroke promotes activation of astrocytes by modulation of miR-488-3p/RAC1

We aim to research the molecular mechanism of lncRNA NEAT1 in the activation of astrocytes in a cerebral ischemia-reperfusion injury model. Mouse model of cerebral ischemia-reperfusion injury was constructed, and shNEAT1 was transfected. The infarct area, brain water content, and neurological deficiency were detected. Immunofluorescence detection and fluorescence in situ hybridization (FISH) assay were processed to detect glial fibrillary acidic protein (GFAP) expression. Astrocyte cells were cultured for oxygen-glucose deprivation/re-oxygenation (OGD)/re-oxygenation model construction. After treatment by shNEAT1, miR-488-3p mimic, miR-488-3p inhibitor, Q-PCR assay, western blot and ELISA were undertaken to detect the expressions of NEAT1, miR-488-3p, RAC1, inflammatory cytokines, RAC1 and GFAP. Dual luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were used to verify the binding of NEAT1, miR-488-3p and RAC1. The expression of NEAT1 in brain tissue was significantly higher than that in Sham operation group. Knockdown of NEAT1 inhibited the brain damage caused by middle cerebral artery occlusion (MCAO) treatment, reduced the inflammatory response, and suppressed the activation of astrocytes. By constructing an in vitro OGD/R cell model, it was found that NEAT1 knockdown also inhibited the activation of astrocytes caused by OGD/R. Knockdown of NEAT1 caused the up-regulation of miR-488-3p and the down-regulation of RAC1. Knockdown of miR-488-3p or over-expression of RAC1 reversed the inhibitory effect of shNEAT1 on OGD/R-induced astrocyte activation. Over-expression of NEAT1 in cerebral ischemic stroke promotes activation of astrocytes by modulation miR-488-3p/RAC1, which is proved in vitro. Our study may provide a new idea for the diagnosis and treatment of MCAO.

The lncRNA NEAT1 Mediates Neuronal Cell Autophagy and Related Protein Expression After Cerebral Ischemia‒Reperfusion Injury.

The present study focuses on the role of the long noncoding RNA (lncRNA) NEAT1 in regulating autophagy during the ischemia‒reperfusion (I/R) injury process and its possible regulatory mechanism based on the results of laboratory experiments. Neuro-2a (N2a) cells and BV-2 microglial cells were cultured separately, and oxygen-glucose deprivation/reoxygenation (OGD/R) was induced in vitro to mimic cerebral I/R injury. The expression of lncRNA NEAT1 was measured after reoxygenation for different durations, and the results showed that NEAT1 expression was significantly different after OGD/R for 12h; thus, cell models of NEAT1 overexpression and knockdown were constructed. Knockdown of NEAT1 effectively relieved reperfusion injury. In an N2a and BV-2 cell coculture system, knockdown of NEAT1 reduced autophagic flow in neuronal cells after reperfusion. To clarify the mechanism of NEAT1 after neuronal I/R injury, label-free quantitative proteomics (LFQ) was used to identify the differentially expressed proteins (DEPs) in NEAT1 knockdown neurons after OGD/R for 12h. Additionally, Gene Ontology (GO) enrichment, protein‒protein interaction (PPI) network and parallel-reaction monitoring (PRM) quantitative analyses were carried out; the results showed that the expression levels of the autophagy-related proteins Gaa, Glb1, Prkaa1, Kif23, Sec24a and Vps25 were significantly reduced and that these proteins interact. In summary, this study shows that NEAT1 can regulate the interactions between autophagy-related proteins after neuronal I/R injury, reducing the level of autophagy and relieving neuronal reperfusion injury.

Oxidative stress-induced endothelial cells-derived exosomes accelerate skin flap survival through Lnc NEAT1-mediated promotion of endothelial progenitor cell function

BackgroundFlap transplantation is commonly used in reconstructive surgery. A prerequisite for skin flap survival is sufficient blood supply. However, such approaches remain unclear. This study aimed to explore the underlying mechanisms of exosomes derived from human umbilical vascular endothelial cells (HUVECs) exposed to oxidative stress on endothelial progenitor cells (EPCs) and their subsequent influence on the survival of skin flaps.MethodsHUVECs were treated with various concentrations of H2O2 to establish an oxidative stress model. To investigate the effects of H2O2-HUVEC-Exos and HUVEC-Exos, Cell Counting Kit-8, tube formation, invasion assays, and quantitative real-time polymerase chain reaction (qRT-PCR) were performed in EPCs. Microarray analysis was used to reveal the differentially expressed long non-coding RNAs (lncRNAs) in the H2O2-HUVEC-Exos and HUVEC-Exos. In addition, gene silencing and western blotting were employed to determine the mechanism behind lncRNA nuclear enrichment enriched transcript 1 (Lnc NEAT1) in EPCs. Further, a rat skin flap model was used to determine the role of the exosomes in skin flap survival in vivo.ResultsHUVECs were stimulated with 100 μmol/L H2O2 for 12 h to establish an oxidative stress model. H2O2-HUVEC-Exos promoted the proliferation, tube formation, and invasion of EPCs and remarkably increased skin flap survival compared to the HUVEC-Exos and control groups. Sequencing of exosome RNAs revealed that the Lnc NEAT1 level was dramatically increased in the H2O2-HUVEC-Exos, leading to activation of the Wnt/β-catenin signaling pathway. Comparatively, knockdown of Lnc NEAT1 in HUVEC-Exos and H2O2-HUVEC-Exos significantly inhibits the angiogenic capacity of EPCs, reduced the survival area of skin flap and downregulated the expression levels of Wnt/β-catenin signaling pathway proteins, whereas Wnt agonist partly reversed the negative effect of NEAT1 downregulation on EPCs through the Wnt/β-catenin signaling pathway.ConclusionsExosomes derived from HUVECs stimulated by oxidative stress significantly promoted the pro-angiogenic ability of EPCs through the Wnt/β-catenin signaling pathway mediated by Lnc NEAT1 and hence enhanced random flap survival in vivo. Therefore, the application of H2O2-HUVEC-Exos may serve as an alternative therapy for improving random skin flap survival.

FC 119: Kidney-Specific Silencing of Neat1 Alleviates Diabetic Kidney Injury

Abstract BACKGROUND AND AIMS Long noncoding RNA Nuclear Enriched Abundant Transcript 1 (Neat1) not only serves as a key structural component of nuclear paraspeckle, but is also involved in a variety of pathophysiological processes. Our previous study shows that increased Neat1 expression is closely associated with the pathogenesis of acute kidney injury. Here, we investigate whether Neat1 plays a role in chronic kidney disease and diabetes (DKD). METHOD Neat1 expression on kidney biopsies of patients with DKD and other nondiabetic kidney disease was measured by in situ hybridization. Normal portions of kidney tissues removed from nephrectomy specimens for the treatment of renal carcinoma was used as control. In vivo, streptozotocin (STZ)-induced DKD was established in uninephrectomized C57BL/6 mice with low-dose STZ (50 mg/kg) injection for five consecutive days. Mice injected with citrate buffer were used as control. Neat 1 gene was subsequently knocked down in the kidney by shRNA gene silencing via ultrasound-mediated microbubble technique every 2 weeks. All mice were sacrificed at 10 weeks after STZ injection for renal histopathological examination, urine albumin-to-creatinine ratio (UACR) measurement and Neat 1 expression analysis. RESULTS Kidney Neat 1 expression was increased significantly in DKD patients compared with control and other kidney diseases (Figure 1). Similarly, Neat1 was induced in STZ-induced diabetic kidneys while its expression was markedly suppressed following shRNA knockdown as confirmed by real-time qPCR (Figure 2A, C and E). Compared with nondiabetic control, diabetic mice presented increased UACR with significant tubular dilatation and atrophy, while knockdown of Neat1 attenuated both proteinuria and kidney injury in the diabetic mice (Figure 2B, D and F). CONCLUSION Increased Neat 1 expression contributes to the pathogenesis of DKD and targeting Neat 1 may be a novel and potential therapeutic strategy for diabetic kidney injury.

LncRNA NEAT1 sponges miR-214 to promoted tumor growth in hepatocellular carcinoma.

Live cancer is the sixth most prevalent diagnosed malignant tumor and the fourth leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the main histological type of liver cancer. Here, we attempt to evaluate the role of long non coding RNA NEAT1 in HCC, and explore its potential mechanism in this disease. Initially, we detected the expression of NEAT1 in HCC cell lines (SMMC-7721 and Huh7 cells) using qRT-PCR. Then we transfected si-NC or si-NEAT1 into SMMC-7721 and Huh7 cells by RNA interference. CCK-8 assay, transwell assay, flow cytometry, qRT-PCR and western blotting were used to evaluate the role of NEAT1 in the biological behavior of SMMC-7721 and Huh7 cells. The rescue experiment, RIP assay and MeRIP were devoted to the underlying mechanism. NEAT1 expression level was significantly elevated in SMMC-7721 and Huh7 cells. Knockdown of NEAT1 inhibited proliferation and migration, induced apoptosis of HCC cell lines. NEAT1 serves as a sponge for miR-214. Besides, PSMB8 was a direct target of miR-214. Furthermore, ALKBH5 could up-regulate NEAT1 expression by inhibiting m6A enrichment. ALKBH5-induced NEAT1 promoted cell proliferation and migration of HCC by sponging miR-214 in vitro, which may provide a potential therapeutic target for HCC.