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Early‐life stress (ES) induced by maternal separation (MS) remains a proven causality of anxiety and memory deficits at later stages of life. Emerging studies have shown that MS‐induced gene expression in the hippocampus is operated at the level of transcription. However, the extent of involvement of non‐coding RNAs in MS‐induced behavioural deficits remains unexplored. Here, we have investigated the role of synapse‐enriched long non‐coding RNAs (lncRNAs) in anxiety and memory upon MS. We observed that MS led to an enhancement of expression of the lncRNA growth arrest specific 5 (Gas5) in the hippocampus; accompanied by increased levels of anxiety and deficits in spatial memory. Gas5 knockdown in early life was able to reduce anxiety and partially rescue the spatial memory deficits of maternally separated adult mice. However, the reversal of MS‐induced anxiety and memory deficits is not attributed to Gas5 activity during neuronal development as Gas5 RNAi did not influence spine development. Gene Ontology analysis revealed that Gas5 exerts its function by regulating RNA metabolism and translation. Our study highlights the importance of MS‐regulated lncRNA in anxiety and spatial memory. [ABSTRACT FROM AUTHOR]

Introduction: Myocardial hypoxia is an important factor causing myocardial infarction (MI). Interestingly, many unknown factors in the molecular mechanism of MI remain unclear. Our study explored the role of lncRNA growth arrest‐specific 5 (GAS5) in cell injury under hypoxia. Methods: AS5 expression was assessed in MI and human cardiomyocytes under hypoxia through RT‐qPCR assay. Methyl thiazolyl tetrazolium assay, flow cytometry assay, and transwell assay was carried out for cell viability, cell apoptosis, cell migration, and invasion, respectively. The regulatory target of GAS5 was explored through a dual‐luciferase reporter assay. Results: Our findings indicated that the upregulation of GAS5 was related to hypoxia. Downregulation of GAS5 expression could decrease hypoxia‐induced cell apoptosis and increase cell migration and invasion. Moreover, GAS 5 targeted miR‐21, which regulated the phosphatase and tension homology deleted on chromosome ten gene (PTEN) expression. Furthermore, the knockdown of miR‐21 eliminated the effect of GAS5 silencing on cell injury. Conclusion: These results indicated that lncRNA GAS5 silencing decreased cardiomyocyte injury by hypoxia‐induced through regulating miR‐21/PTEN. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy (CH) is a pathological phenotype of cardiomyopathy. Epigenetic modification is a mechanism associated with CH. Our study here investigated the histone demethylase KDM3C in relation to epigenetic regulation in CH. We found that KDM3C mRNA silencing alleviated CH, as evidenced by reduced ANP, BNP, and β‐MHC mRNAs, increased α‐MHC mRNA, decreased cell surface area, and reduced cellular protein/DNA ratios. Specifically, KDM3C upregulated miR‐200c‐3p expression through demethylation of H3K9me2, leading to enhanced binding of miR‐200c‐3p to GAS5 and suppression of GAS5 expression; these effects then led to reduced binding of GAS5 to miR‐495‐3p, increased miR‐495‐3p expression, and repression of PHF8 transcription. Through these mechanisms, our data indicate that KDM3C‐dependent epigenetic modification promotes CH. [ABSTRACT FROM AUTHOR]

Growth arrest‐specific 6 (GAS6) protein plays a key role in processes related to proliferation, inflammation, angiogenesis, and atherosclerotic plaque formation. In addition, it has been reported that plasma levels of GAS6 are related to cancer prognosis and other relevant pathologies, such as heart failure or sepsis. We report here the first electrochemical immunoplatform for the determination of GAS6, which has demonstrated to be competitive with other available methodologies in terms of cost, simplicity, and decentralized application. The developed immunoplatform involves a sandwich immunoassay using magnetic microparticles (MBs) and uses amperometric detection at disposable screen‐printed carbon electrodes (SPCEs). The MBs were modified with an antibody specific to GAS6 for its selective capture, which is further recognized by a biotinylated secondary antibody subsequently labeled with a streptavidin‐horseradish peroxidase (Strep‐HRP) conjugate. The electrochemical detection was carried out using the hydroquinone (HQ)/H2O2 system. The developed bioplatform exhibits a great selectivity and low limit of detection (27 pg/mL) that allowed the determination of the GAS6 circulating level in plasma samples from patients suffering heart failure (HF) and diagnosed with pancreatic ductal adenocarcinoma (PDAC), as well as the determination of the target protein in raw secretomes of human colorectal cancer cell lines. [ABSTRACT FROM AUTHOR]

Pyroptosis is a novel proinflammatory programmed cell death process. This study was designed to investigate the functional mechanisms of long noncoding RNA growth arrest‐specific transcript 5 (lncRNA GAS5) on lipopolysaccharide (LPS)‐induced human bronchial epithelial cell (HBEC) pyroptosis. LPS was used to induce pyroptosis in HBECs, followed by the detection of the expression of GAS5, forkhead box O3 (FOXO3), and nuclear factor E2‐related factor 2/heme oxygenase 1 (Nrf2/HO‐1) signaling pathway‐related factors. Cell viability was evaluated using CCK‐8 assay, lactate dehydrogenase (LDH) release was assessed by LDH assay kit and caspase‐1 activity by flow cytometry. Furthermore, expression of NOD‐like receptor family pyrin domain containing 3 and pyroptosis‐related proteins was evaluated using Western blot analysis, while enzyme‐linked immunosorbent assay was used to determine the levels of inflammatory factors. The interaction between GAS5 and FOXO3 was confirmed using bioinformatic prediction, RNA immunoprecipitation assay, RNA pull‐down, and dual‐luciferase reporter gene assay. Treatment of HBECs with LPS upregulated the expression of GAS5 and FOXO3, resulting in the inactivation of the Nrf2/HO‐1 signaling pathway. On the other hand, inhibition of both GAS5 and FOXO3 promoted cell viability, reduced LDH release, pyroptosis, and inflammatory response in LPS‐induced HBECs. Furthermore, FOXO3 could interact with GAS5, while FOXO3 overexpression reversed the inhibitory effect of GAS5 knockdown on cell pyroptosis. Thus, mechanistically, inhibition of FOXO3 activates the Nrf2/HO‐1 pathway to suppress LPS‐induced pyroptosis in HBECs. This study revealed that GAS5 knockdown attenuates FOXO3 expression thereby activating the Nrf2/HO‐1 pathway to inhibit LPS‐induced pyroptosis in HBECs. These findings may contribute to identifying novel targets that inhibit pyroptosis in HBECs. [ABSTRACT FROM AUTHOR]

Introduction: LncRNA growth arrest‐specific transcript 5 (GAS5) has been proven to be involved in autoimmune diseases. Rheumatoid arthritis is a type of autoimmune disease that may affect myasthenia gravis (MG) patients. However, its direct role in MG is unknown. Methods: Our study included 62 generalized MG patients. GAS5 expression was analyzed with real‐time quantitative RT‐PCR (qRT‐PCR). The interaction between GAS5 and interleukin 10 (IL‐10) was explored in overexpressed cells using real time quantitative polymerase chain reactions (RT‐qPCRs) and western blot. The correlation of GAS5 and IL‐10 was analyzed using Pearson's correlation analysis. The diagnostic value of GAS5 for MG was analyzed using receiver operating characteristic (ROC) curve analysis. Results: GAS5 and IL‐10 mRNA levels in peripheral blood mononuclear cells (PBMCs) were significantly lower in MG patients than healthy controls. Downregulated GAS5 effectively distinguished MG patients from healthy controls. GAS5 expression was positively correlated with IL‐10 expression in both MG patients and healthy controls. GAS5 overexpression significantly upregulated IL‐10 expression in PBMCs derived from both MG patients and healthy controls. Conclusion: LncRNA GAS5 may improve generalized MG by positively regulating IL‐10 expression. [ABSTRACT FROM AUTHOR]

Tumour‐associated macrophage (TAM) polarization is associated with hepatocellular carcinoma but the molecular mechanism of this polarization is still unknown. Peripheral blood mononuclear cells were induced to differentiate into M0, M1 and M2 macrophages and TAMs. TAMs were transfected with pcDNA3.1‐GAS5, pcDNA3.1‐NC, si‐GAS5, si‐PTEN or si‐Ctrl. A human liver cancer cell line (SMCC‐7721) was incubated with the modified TAM supernatant. Quantitative real‐time PCR and Western blot were performed to detect gene and protein expression. The cell proliferation and invasion properties of the SMCC‐7721 cells were detected by MTT and Transwell assays. GAS5 is up‐regulated in M1 macrophages and down‐regulated in M2 macrophages and TAMs. GAS5 overexpression promoted M1‐like polarization of TAMs and inhibited M2‐like polarization of TAMs. Moreover, GAS5 promoted the expression of PTEN in TAMs. PTEN‐silenced TAM supernatant treatment promoted cell proliferative and invasive properties of the SMCC‐7721 cells and diminished the effect of GAS5‐overexpressed TAM supernatant on the cell proliferation and invasion by SMCC‐7721 cells. Our results demostrared that GAS5 overexpression inhibited M2‐like polarization of TAMs by enhancing PTEN expression, thereby inhibiting cell proliferation and invasion by SMCC‐7721 cells. Thus, our results suggest that GAS5 may be a new therapeutic target for HCC treatment. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA) is an inflammatory disease, which seriously affects human joints. This study aimed to detect the changes in the expression of long non‐coding RNA growth arrest‐specific transcript 5 (GAS5) in peripheral blood mononuclear cells (PBMCs) derived from patients with RA and healthy controls (HC), as well as analyze the correlation between GAS5 and clinical indicators of RA. Also, the role and mechanism of GAS5 in regulating the AMP‐activated protein kinase (AMPK) pathway in RA was further assessed. Methods: The PBMCs were isolated from the RA patients. Next, GAS5 expression was detected in RA PBMCs by quantitative real‐time polymerase chain reaction, and its diagnostic value on RA was determined by receiver operating characteristic curves (ROC). The levels of interleukin (IL)‐6 and IL‐17 were detected via enzyme‐linked immunosorbent assay. The expressions of total and phosphorylated AMPK as well as p38MAPK were determined with Western blot. Results: GAS5 was down‐regulated in RA PBMCs, and consequently serves as a potential diagnostic marker for RA (sensitivity, 90%; specificity, 80%; area under the curve, 0.89). Further, GAS5 negatively regulated erythrocyte sedimentation rate, C‐reactive protein, Disease Activity Score of 28 joints and antibodies against cyclic citrullinated peptide, as well as the IL‐6 and IL‐17 levels of RA PBMCs. Similarly, GAS5 was observed to activate the AMPK pathway. Conclusion: GAS5 activated the AMPK pathway, while it negatively regulated the expression of cytokines IL‐6 and IL‐17. [ABSTRACT FROM AUTHOR]

Aim: Long non‐coding RNA (lncRNAs) have been shown to play a critical role in a variety of pathophysiological processes, such as cell proliferation, apoptosis and migration. However, there were few studies addressing the function of lncRNAs in renal ischaemia/reperfusion (I/R) injury. Apoptosis is an important pathogenesis during I/R injury. Here, we identified the effect of hypoxia‐responsive lncRNA growth arrest‐specific 5 (GAS5) on apoptosis in renal I/R injury. Methods: Ischaemia/reperfusion injury in mice or hypoxia/re‐oxygenation (H/R) in human proximal renal tubular epithelial cells (HK‐2) was practiced to induce apoptosis. The kidneys and blood were collected at 24 h after reperfusion. The GAS5 messenger RNA (mRNA) expression and apoptosis‐related gene mRNA and protein levels, including p53, cellular inhibitor of apoptosis protein 2 (cIAP2) and thrombospondin‐1 (TSP‐1), were analysed. GAS5 small‐interfering RNA was transfected with H/R induced cells. Over‐expression of GAS5 was performed by plasmid transfection. Results: Apoptotic cells significantly increased in I/R‐injured kidneys. GAS5 could be up‐regulated in kidneys at 24 h after reperfusion and 3 h after re‐oxygenation, combined with increased expression of its downstream apoptosis‐related proteins p53 and cIAP2. GAS5 small‐interfering RNA treatment down‐regulated the mRNA and protein levels of p53 and TSP‐1, and attenuated apoptosis induced by H/R in HK‐2 cells. Conversely, over‐expression of GAS5 up‐regulated the mRNA and protein levels of p53 and TSP‐1, and promoted apoptosis in HK‐2 cells. Conclusion: Long non‐coding RNA GAS5 induced by I/R injury could promote apoptosis in kidney. TSP‐1 might be one of the downstream effectors of GAS5, which will be explored in the future. Summary at a Glance: In this study, the role of the long non‐coding RNA growth arrest‐specific 5 was examined in ischaemia/reperfusion injury of the kidney and in the HK‐2 cell line and found to promote apoptosis. [ABSTRACT FROM AUTHOR]