Non-coding RNA NEAT1 Research Articles

NEAT1-mediated regulation of proteostasis and mRNA localization impacts autophagy dysregulation in Rett syndrome.

Rett syndrome (RTT) is a severe neurodevelopmental disorder primarily caused by loss-of-function mutations in the MECP2 gene, resulting in diverse cellular dysfunctions. Here, we investigated the role of the long noncoding RNA (lncRNA) NEAT1 in the context of MeCP2 deficiency using human neural cells and RTT patient samples. Through single-cell RNA sequencing and molecular analyses, we found that NEAT1 is markedly downregulated in MECP2 knockout (KO) cells at various stages of neural differentiation. NEAT1 downregulation correlated with aberrant activation of the mTOR pathway, abnormal protein metabolism, and dysregulated autophagy, contributing to the accumulation of protein aggregates and impaired mitochondrial function. Reactivation of NEAT1 in MECP2-KO cells rescued these phenotypes, indicating its critical role downstream of MECP2. Furthermore, direct RNA-RNA interaction was revealed as the key process for NEAT1 influence on autophagy genes, leading to altered subcellular localization of specific autophagy-related messenger RNAs and impaired biogenesis of autophagic complexes. Importantly, NEAT1 restoration rescued the morphological defects observed in MECP2-KO neurons, highlighting its crucial role in neuronal maturation. Overall, our findings elucidate lncRNA NEAT1 as a key mediator of MeCP2 function, regulating essential pathways involved in protein metabolism, autophagy, and neuronal morphology.

Upregulation of FAM129B protects against glucocorticoid-induced skeletal muscle atrophy via regulating long non-coding RNA NEAT1.

Skeletal muscle atrophy, manifested by a reduction in muscle size and quantity, is primarily attributed to excessive protein catabolism. FAM129B, an antioxidant protein, has been previously implicated in muscle growth and development in cattle. Aim of this study is to elucidate the role of FAM129B in muscle atrophy. FAM129B was consistently down-regulation in muscle atrophy models in vitro and in vivo and in human steroid-treated gluteus muscles. FAM129B depletion resulted in myotubes atrophy with reduced diameter, increased MuRF-1 and Atrogin-1. Conversely, FAM129B overexpression ameliorated muscle atrophy by increasing myotube diameter and reducing Atrogin-1 and MuRF-1. Mice overexpressing FAM129B exhibited resistance to muscle atrophy, evidenced by increased grip strength, increased tibial anterior weight, increased myofiber cross-sectional area and decreased MuRF-1 and Atrogin-1. RNA sequencing revealed NEAT1 as a downstream gene of FAM129B. Mechanistically, FAM129B was found to influence the stability of NEAT1 by directly binding to it. The enhanced stability of NEAT1 subsequently led to increased FoxO1 expression and subsequent protein degradation. Our study has provided evidence that the upregulation of FAM129B rescues the Dex-induced skeletal muscle atrophy, suggesting that FAM129B may be a potential target for alleviating skeletal muscle atrophy.

Proline exacerbates hepatic gluconeogenesis via paraspeckle-dependent mRNA retention.

Type 2 diabetes (T2D) is a global health issue characterized by abnormal blood glucose levels and is often associated with excessive hepatic gluconeogenesis. Increased circulating non-essential amino acids (NEAAs) are consistently observed in individuals with T2D; however, the specific contribution of each amino acid to T2D pathogenesis remains less understood. Here, we report an unexpected role of the NEAA proline in coordinating hepatic glucose metabolism by modulating paraspeckle, a nuclear structure scaffolded by the long non-coding RNA Neat1. Mechanistically, proline diminished paraspeckles in hepatocytes, liberating the retained mRNA species into cytoplasm for translation, including the mRNAs of Ppargc1a and Foxo1, contributing to enhanced gluconeogenesis and hyperglycaemia. We further demonstrated that the proline-paraspeckle-mRNA retention axis existed in diabetic liver samples, and intervening in this axis via paraspeckle restoration substantially alleviated hyperglycaemia in both female and male diabetic mouse models. Collectively, our results not only delineated a previously unappreciated proline-instigated, paraspeckle-dependent mRNA-retention mechanism regulating gluconeogenesis, but also spotlighted proline and paraspeckle as potential targets for managing hyperglycaemia.

Histone Lactylation-Driven YTHDC1 Promotes Hepatocellular Carcinoma Progression via Lipid Metabolism Remodeling.

Lipid metabolism reprogramming is critical for the initiation and progression of hepatocellular carcinoma (HCC). However, how the dysregulation of lipid metabolism contributes to HCC development remains largely unknown. Here, we report that the m6A reader YTHDC1-mediated epigenetic regulation of the long noncoding RNA NEAT1 activates stearoyl-CoA desaturase (SCD)-associated lipid metabolic processes during HCC progression. Mechanistically, histone lactylation in HCC induces increased expression of YTHDC1, increasing the stability of m6A-modified NEAT1. The histone acetyltransferase p300 is then recruited by NEAT1 and activates SCD by increasing the level of histone acetylation at the SCD promoter, thus facilitating HCC progression via hepatocellular lipid metabolism remodeling. Taken together, these discoveries suggest a close link between the epigenetic machinery and lipid metabolic abnormalities, which promotes cancer progression.

ATRA-induced NEAT1 upregulation promotes autophagy during APL cell granulocytic differentiation

Aims Acute promyelocytic leukemia (APL) progresses quickly and often leads to early hemorrhagic death. Treatment with all-trans retinoic acid (ATRA) promotes differentiation of APL cells and clinical remission, making APL a potentially curable malignancy. Understanding how ATRA works may lead to new treatments for other types of leukemia. Long non-coding RNA NEAT1 has been implicated in the differentiation of APL cells. This study aims to elucidate the specific role of NEAT1 in the granulocytic differentiation of APL. Methods The influence of NEAT1 on autophagy and PML/RARα degradation was assessed using western blot assays. The impact of NEAT1 on the expression of autophagy-related genes was evaluated through quantitative real-time RT-PCR. Mechanistic insights into the role of NEAT1 in modulating autophagy were supported by RNA immunoprecipitation and RNA pulldown assays. Key findings Knockdown of NEAT1 suppressed autophagy and attenuated ATRA-induced PML/RARα degradation and granulocytic differentiation of APL cells. Subsequent screening of autophagy-related genes demonstrated that silencing NEAT1 impaired the ATRA-induced upregulation of ATG10 and ATG12. Mechanistic investigations revealed that the RNA-binding protein TAF15 interacted with NEAT1, synergistically stabilizing the mRNA of ATG10 and ATG12. Furthermore, knockdown of NEAT1 impaired the interactions between TAF15 and the mRNAs of ATG10 and ATG12, thereby compromising their mRNA stability. Significance Our study elucidates the critical role of NEAT1-mediated autophagy in the differentiation of APL cells and delineates the molecular mechanism by which upregulation of NEAT1 enhances autophagy. Specifically, NEAT1 binds to the RNA-binding protein TAF15, which in turn stabilizes the mRNA of both ATG10 and ATG12.

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.

The long non-coding RNA NEAT1 contributes to aberrant STAT3 signaling in pancreatic cancer and is regulated by a metalloprotease-disintegrin ADAM8/miR-181a-5p axis.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers and several studies demonstrate that STAT3 has critical roles throughout the course of PDAC pathogenesis. TCGA, microarray, and immunohistochemistry data from a PDAC cohort were used for clinical analyses. Panc89 cells with ADAM8 knockout, re-expression of ADAM8 mutants, and Panc1 cells overexpressing ADAM8 were generated. Gene expression analyses of ADAM8, STAT3, long non-coding (lnc) RNA NEAT1, miR-181a-5p and ICAM1 were performed by quantitative PCR. Subcellular fractionation quantified NEAT1 expression in cytoplasm and nucleus of PDAC cell lines. Cell proliferation, scratch, and invasion assays were performed to detect growth rate, migration and invasion capabilities of cells. Gain and loss of function experiments were carried out to investigate the biological effects of lncRNA NEAT1 and miR-181a-5p on PDAC cells and downstream genes. Dual-luciferase reporter gene assay determined interaction and binding sites of miR-181a-5p in lncRNA NEAT1. Pull down assays, RNA binding protein immunoprecipitation (RIP), and ubiquitination assays explored the molecular interaction between lncRNA NEAT1 and STAT3. High ADAM8 expression causes aberrant STAT3 signaling in PDAC cells and is positively correlated with NEAT1 expression. NEAT1 binding to STAT3 was confirmed and prevents STAT3 degradation in the proteasome as increased degradation of STAT3 was observed in ADAM8 knockout cells and cells treated with bortezomib. Furthermore, miRNA-181a-5p regulates NEAT1 expression by direct binding to the NEAT1 promoter. ADAM8 regulates intracellular STAT3 levels via miR-181a-5p and NEAT1 in pancreatic cancer.

NEAT1 modulates the TIRR/53BP1 complex to maintain genome integrity.

Tudor Interacting Repair Regulator (TIRR) is an RNA-binding protein (RBP) that interacts directly with 53BP1, restricting its access to DNA double-strand breaks (DSBs) and its association with p53. We utilized iCLIP to identify RNAs that directly bind to TIRR within cells, identifying the long non-coding RNA NEAT1 as the primary RNA partner. The high affinity of TIRR for NEAT1 is due to prevalent G-rich motifs in the short isoform (NEAT1_1) region of NEAT1. This interaction destabilizes the TIRR/53BP1 complex, promoting 53BP1's function. NEAT1_1 is enriched during the G1 phase of the cell cycle, thereby ensuring that TIRR-dependent inhibition of 53BP1's function is cell cycle-dependent. TDP-43, an RBP that is implicated in neurodegenerative diseases, modulates the TIRR/53BP1 complex by promoting the production of the NEAT1 short isoform, NEAT1_1. Together, we infer that NEAT1_1, and factors regulating NEAT1_1, may impact 53BP1-dependent DNA repair processes, with implications for a spectrum of diseases.

The cellular paraspeckle component SFPQ associates with the viral processivity factor ORF59 during lytic replication of Kaposi's Sarcoma-associated herpesvirus (KSHV)

Kaposi's sarcoma-associated herpesvirus (KSHV) relies on many cellular proteins to complete replication and generate new virions. Paraspeckle nuclear bodies consisting of core ribonucleoproteins splicing factor proline/glutamine-rich (SFPQ), Non-POU domain-containing octamer-binding protein (NONO), and paraspeckle protein component 1 (PSPC1) along with the long non-coding RNA NEAT1, form a complex that has been speculated to play an important role in viral replication. Paraspeckle bodies are multifunctional and involved in various processes including gene expression, mRNA splicing, and anti-viral defenses. To better understand the role of SFPQ during KSHV replication, we performed SFPQ immunoprecipitation followed by mass spectrometry from KSHV-infected cells. Proteomic analysis showed that during lytic reactivation, SFPQ associates with viral proteins, including ORF10, ORF59, and ORF61. These results are consistent with a previously reported ORF59 proteomics assay identifying SFPQ. To test if the association between ORF59 and SFPQ is important for replication, we first identified the region of ORF59 that associates with SFPQ using a series of 50 amino acid deletion mutants of ORF59 in the KSHV BACmid system. By performing co-immunoprecipitations, we identified the region spanning amino acids 101–150 of ORF59 as the association domain with SFPQ. Using this information, we generated a dominant negative polypeptide of ORF59 encompassing amino acids 101–150, that disrupted the association between SFPQ and full-length ORF59, and decreased virus production. Interestingly, when we tested other human herpesvirus processivity factors (EBV BMRF1, HSV-1 UL42, and HCMV UL44) by transfection of each expression plasmid followed by co-immunoprecipitation, we found a conserved association with SFPQ. These are limited studies that remain to be done in the context of infection but suggest a potential association of SFPQ with processivity factors across multiple herpesviruses.

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.

Huntingtin is an RNA binding protein and participates in NEAT1-mediated paraspeckles.

Huntingtin protein, mutated in Huntington's disease, is implicated in nucleic acid-mediated processes, yet the evidence for direct huntingtin-nucleic acid interaction is limited. Here, we show wild-type and mutant huntingtin copurify with nucleic acids, primarily RNA, and interact directly with G-rich RNAs in in vitro assays. Huntingtin RNA-immunoprecipitation sequencing from patient-derived fibroblasts and neuronal progenitor cells expressing wild-type and mutant huntingtin revealed long noncoding RNA NEAT1 as a significantly enriched transcript. Altered NEAT1 levels were evident in Huntington's disease cells and postmortem brain tissues, and huntingtin knockdown decreased NEAT1 levels. Huntingtin colocalized with NEAT1 in paraspeckles, and we identified a high-affinity RNA motif preferred by huntingtin. This study highlights NEAT1 as a huntingtin interactor, demonstrating huntingtin's involvement in RNA-mediated functions and paraspeckle regulation.

Meta-analysis of the correlation between high expression of lncRNA NEAT1 in rectal cancer and pathological features and prognosis.

To systematically evaluate the relationship between the expression level of long noncoding RNA NEAT1 and the clinical characteristics and prognostic value of rectal cancer patients. PubMed, EMBASE, Cochrane library database and case-control studies on the correlation between abnormal expression of lncRNA NEAT1 and prognosis of rectal cancer patients published by the American clinical trials registry before May 1, 2023 were searched. The search time was from the establishment of the database to May 30, 2023. A total of 7 case-control studies were included, including 1063 cancer patients. The results of meta-analysis showed that the high expression of lncRNA NEAT1 was significantly correlated with the degree of differentiation [or=0.45, 95%CI=0.32-0.63, P<0.01], tumor size [or=0.59, 95%CI=0.42-0.82, P<0.01], and overall survival [HR=1.34, 95%CI=1.21-1.48, P<0.001]; However, it was not associated with gender [or=1.23, 95%CI= 0.88-1.72, P=0.23] and lymph node metastasis [or=0.87, 95%CI=0.45-1.66, P=0.67]. The high expression of lncRNA NEAT1 may be a risk factor for poor prognosis in patients with malignant tumors, and lncRNA NEAT1 can be used as a potential biomarker to evaluate its prognosis.

PTDP-43 levels correlate with cell type specific molecular alterations in the prefrontal cortex of C9orf72 ALS/FTD patients.

Repeat expansions in the C9orf72 gene are the most common genetic cause of amyotrophic lateral sclerosis and familial frontotemporal dementia (ALS/FTD). To identify molecular defects that take place in the dorsolateral frontal cortex of patients with C9orf72 ALS/FTD, we compared healthy controls with C9orf72 ALS/FTD donor samples staged based on the levels of cortical phosphorylated TAR DNA binding protein (pTDP-43), a neuropathological hallmark of disease progression. We identified distinct molecular changes in different cell types that take place during FTD development. Loss of neurosurveillance microglia and activation of the complement cascade take place early, when pTDP-43 aggregates are absent or very low, and become more pronounced in late stages, suggesting an initial involvement of microglia in disease progression. Reduction of layer 2-3 cortical projection neurons with high expression of CUX2/LAMP5 also occurs early, and the reduction becomes more pronounced as pTDP-43 accumulates. Several unique features were observed only in samples with high levels of pTDP-43, including global alteration of chromatin accessibility in oligodendrocytes, microglia, and astrocytes; higher ratios of premature oligodendrocytes; increased levels of the noncoding RNA NEAT1 in astrocytes and neurons, and higher amount of phosphorylated ribosomal protein S6. Our findings reveal previously unknown progressive functional changes in major cell types found in the frontal cortex of C9orf72 ALS/FTD patients that shed light on the mechanisms underlying the pathology of this disease.

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.

LncRNA NEAT1 Promotes the Cancer Stem Cell-Like Properties of HCC by miR-128-3p/GP73 Axis

In this study, we investigated the role of long non-coding RNA NEAT1 in hepatocellular carcinoma (HCC) and its impact on liver cancer cell behavior, particularly their cancer stem cell (CSC)-like properties. We observed elevated NEAT1 levels in HCC cell lines and tissues, and this upregulation was associated with adverse clinical characteristics and poor prognosis in HCC patients. Through in vitro experiments, we found that silencing NEAT1 in HCC cells led to decreased cell proliferation, migration, invasion, and inhibited epithelial-mesenchymal transition (EMT) in Huh7 cells. Additionally, the unique surface markers of CSCs were downregulated upon NEAT1 knockdown. Further investigation revealed that NEAT1 regulates the expression of GP73 by directly binding to miR-128-3p, functioning as a competitive ceRNA to suppress miR-128-3p expression. Rescue experiments showed that inhibiting miR-128-3p expression reversed the effects of NEAT1 knockdown on HCC cell proliferation,migration, and invasion. In summary, our findings demonstrate that lncRNA NEAT1 plays a pivotal role in promoting HCC progression and enhancing CSC properties by upregulating GP7 through competitive binding to miR-128-3p. This insight into the underlying mechanism may have promising implications for the treatment of HCC.

The essential role of architectural noncoding RNA Neat1 in cold-induced beige adipocyte differentiation in mice.

Neat1 is an architectural RNA that provides the structural basis for nuclear bodies known as paraspeckles. Although the assembly processes by which Neat1 organizes paraspeckle components are well-documented, the physiological functions of Neat1 are not yet fully understood. This is partly because Neat1 knockout (KO) mice, lacking paraspeckles, do not exhibit overt phenotypes under normal laboratory conditions. During our search for conditions that elicit clear phenotypes in Neat1 KO mice, we discovered that the differentiation of beige adipocytes-inducible thermogenic cells that emerge upon cold exposure-is severely impaired in these mutant mice. Neat1_2, the architectural isoform of Neat1, is transiently upregulated during the early stages of beige adipocyte differentiation, coinciding with increased paraspeckle formation. Genes with altered expression during beige adipocyte differentiation typically cluster at specific chromosomal locations, some of which move closer to paraspeckles upon cold exposure. These observations suggest that paraspeckles might coordinate the regulation of these gene clusters by controlling the activity of certain transcriptional condensates that coregulate multiple genes. We propose that our findings highlight a potential role for Neat1 and paraspeckles in modulating chromosomal organization and gene expression, potentially crucial processes for the differentiation of beige adipocytes.

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.

The receptor tyrosine kinase IGF1R and its associated GPCRs are co-regulated by the noncoding RNA NEAT1 in Alzheimer’s disease

The study is based on the complexity of Insulin like growth factor receptor (IGF1R) signaling and its regulation by noncoding RNAs (ncRNAs). IGF1R signaling is an important cascade in Alzheimer’s disease (AD); however, its regulation and roles are poorly understood. Due to the presence of β-arrestin and GPCR Receptor Kinase binding sites, this protein has been termed a ‘functional hybrid’, as it can take part in both kinase and GPCR signaling pathways, further adding to its complexity. The objective of this study is to understand the underlying ncRNA regulation controlling IGF1R and GPCRs in AD to find commonalities in the network. We found through data mining that 45 GPCRs were reportedly deregulated in AD and built clusters based on GO/KEGG pathways to show shared functionality with IGF1R. Eight miRs were further discovered that could coregulate IGF1R and GPCRs. We validated their expression in an AD cell model and probed for common lncRNAs downstream that could regulate these miRs. Seven such candidates were identified and further validated. A combined network comprising IGF1R with nine GPCRs, eight miRs, and seven lncRNAs was created to visualize the interconnectivity within pathways. Betweenness centrality analysis showed a cluster of NEAT1, hsa-miR-15a-5p, hsa-miR-16-5p, and IGF1R to be crucial form a competitive endogenous RNA-based (ceRNA) tetrad that could relay information within the network, which was further validated by cell-based studies. NEAT1 emerged as a master regulator that could alter the levels of IGF1R and associated GPCRs. This combined bioinformatics and experimental study for the first time explored the regulation of IGF1R through ncRNAs from the perspective of neurodegeneration.

N6-methyladenosine reader hnRNPA2B1 recognizes and stabilizes NEAT1 to confer chemoresistance in gastric cancer.

Chemoresistance is a major cause of treatment failure in gastric cancer (GC). Heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) is an N6-methyladenosine (m6A)-binding protein involved in a variety of cancers. However, whether m6A modification and hnRNPA2B1 play a role in GC chemoresistance is largely unknown. In this study, we aimed to investigate the role of hnRNPA2B1 and the downstream mechanism in GC chemoresistance. The expression of hnRNPA2B1 among public datasets were analyzed and validated by quantitative PCR (qPCR), Western blotting, immunofluorescence, and immunohistochemical staining. The biological functions of hnRNPA2B1 in GC chemoresistance were investigated both in vitro and in vivo. RNA sequencing, methylated RNA immunoprecipitation, RNA immunoprecipitation, and RNA stability assay were performed to assess the association between hnRNPA2B1 and the binding RNA. The role of hnRNPA2B1 in maintenance of GC stemness was evaluated by bioinformatic analysis, qPCR, Western blotting, immunofluorescence, and sphere formation assays. The expression patterns of hnRNPA2B1 and downstream regulators in GC specimens from patients who received adjuvant chemotherapy were analyzed by RNAscope and multiplex immunohistochemistry. Elevated expression of hnRNPA2B1 was found in GC cells and tissues, especially in multidrug-resistant (MDR) GC cell lines. The expression of hnRNPA2B1 was associated with poor outcomes of GC patients, especially in those who received 5-fluorouracil treatment. Silencing hnRNPA2B1 effectively sensitized GC cells to chemotherapy by inhibiting cell proliferation and inducing apoptosis both in vitro and in vivo. Mechanically, hnRNPA2B1 interacted with and stabilized long noncoding RNA NEAT1 in an m6A-dependent manner. Furthermore, hnRNPA2B1 and NEAT1 worked together to enhance the stemness properties of GC cells via Wnt/β-catenin signaling pathway. In clinical specimens from GC patients subjected to chemotherapy, the expression levels of hnRNPA2B1, NEAT1, CD133, and CD44 were markedly elevated in non-responders compared with responders. Our findings indicated that hnRNPA2B1 interacts with and stabilizes lncRNA NEAT1, which contribute to the maintenance of stemness property via Wnt/β-catenin pathway and exacerbate chemoresistance in GC.

RETRACTED: Quercetin modulates expression of serum exosomal long noncoding RNA NEAT1 to regulate the miR-129-5p/BDNF axis and attenuate cognitive impairment in diabetic mice

AimsCognitive impairment poses a considerable health challenge in the context of type 2 diabetes mellitus (T2DM), emphasizing the need for effective interventions. This study delves into the therapeutic efficacy of quercetin, a natural flavonoid, in mitigating cognitive impairment induced by T2DM in murine models. Materials and methodsSerum exosome samples were obtained from both T2DM-related and healthy mice for transcriptome sequencing, enabling the identification of differentially expressed mRNAs and long noncoding RNAs (lncRNAs). Subsequent experiments were conducted to ascertain the binding affinity between mmu-miR-129-5p, NEAT1 and BDNF. The structural characteristics and dimensions of isolated exosomes were scrutinized, and the expression levels of exosome-associated proteins were quantified. Primary mouse hippocampal neurons were cultured for in vitro validation, assessing the expression of pertinent genes as well as neuronal vitality, proliferation, and apoptosis capabilities. For in vivo validation, a T2DM mouse model was established, and quercetin treatment was administered. Changes in various parameters, cognitive ability, and the expression of insulin-related proteins, along with pivotal signaling pathways, were monitored. Key findingsAnalysis of serum exosomes from T2DM mice revealed dysregulation of NEAT1, mmu-miR-129-5p, and BDNF. In vitro investigations demonstrated that NEAT1 upregulated BDNF expression by inhibiting mmu-miR-129-5p. Overexpression of mmu-miR-129-5p or silencing NEAT1 resulted in the downregulation of insulin-related protein expression, enhanced apoptosis, and suppressed neuronal proliferation. In vivo studies validated that quercetin treatment significantly ameliorated T2DM-related cognitive impairment in mice. SignificanceThese findings suggest that quercetin holds promise in inhibiting hippocampal neuron apoptosis and improving T2DM-related cognitive impairment by modulating the NEAT1/miR-129-5p/BDNF pathway within serum exosomes.