GAS5 knockdown alleviates spinal cord injury by reducing VAV1 expression via RNA binding protein CELF2

LINC01432 binds to CELF2 in newly diagnosed multiple myeloma promoting short progression-free survival to standard therapy

Multiple Myeloma (MM) is a highly prevalent and incurable form of cancer that arises from malignant plasma cells, with over 35,000 new cases diagnosed annually in the United States. While there are a growing number of approved therapies, MM remains incurable and nearly all patients will relapse and exhaust all available treatment options. Mechanisms for disease progression are unclear and in particular, little is known regarding the role of long non-coding RNAs (lncRNA) in mediating disease progression and response to treatment. In this study, we used transcriptome sequencing to compare newly diagnosed MM patients who had short progression-free survival (PFS) to standard first-line treatment (PFS < 24 months) to patients who had prolonged PFS (PFS > 24 months). We identified 157 differentially upregulated lncRNAs with short PFS and focused our efforts on characterizing the most upregulated lncRNA, LINC01432. We investigated LINC01432 overexpression and CRISPR/Cas9 knockdown in MM cell lines to show that LINC01432 overexpression significantly increases cell viability and reduces apoptosis, while knockdown significantly reduces viability and increases apoptosis, supporting the clinical relevance of this lncRNA. Next, we used individual-nucleotide resolution cross-linking immunoprecipitation with RT-qPCR to show that LINC01432 directly interacts with the RNA binding protein, CELF2. Lastly, we showed that LINC01432-targeted locked nucleic acid antisense oligonucleotides reduce viability and increases apoptosis. In summary, this fundamental study identified lncRNAs associated with short PFS to standard NDMM treatment and further characterized LINC01432, which inhibits apoptosis.

Effects of ADSC-Derived Exosome LRRC75A-AS1 on Anti-inflammatory Function After SCI

Spinal cord injury (SCI) is a highly debilitating disorder of the central nervous system that can severely impact an affected patient's quality of life. This study aimed to examine how adipose-derived mesenchymal stem cell exosomes (ADSC-exos) can be used to treat spinal cord injury. We analysed differentially expressed mRNAs in SCI using bioinformatics data, gene expression profiles in inflammatory cell models, RT-qPCR and WB. Apoptosis was detected with flow cytometry. Starbase provides the control mechanism for FDFT1. Target interactions were detected with dual-luciferase reporter and RIP assays. Exosomes were isolated from adipose tissue-derived mesenchymal stem cells and subsequently characterized with western blot analysis, transmission electron microscopy and nanoparticle tracking analysis. By analysing the GSE102964 database, we found that FDFT1 was significantly downregulated as SCI progressed. Overexpression of FDFT1 can significantly reverse the inflammatory response and apoptosis of BV2 cells induced by hemin. Mechanically, ADSC-exos can affect the expression of FDFT1 through the ceRNA mechanism mediated by LRRC75A-AS1 and in an RBP-dependent manner mediated by IGF2BP2. The overexpression of LRRC75A-AS1 significantly enhances BV2 apoptosis and can be reversed by FDFT1 knockdown. ADSC-exos LRRC75A-AS1 inhibits inflammation and reduces SCI by increasing the expression and stability of FDFT1 mRNA in a ceRNA and RBP-dependent manner.

The RNA binding protein HuR promotes neuronal apoptosis in rats with spinal cord injury via the HDAC1/RAD21 axis

The current research aims to study the regulation of the RNA binding protein HuR on neuronal apoptosis during spinal cord injury (SCI) and its underlying mechanism. SCI rat models were injected with HuR shRNA and/or pcDNA3.1-RAD21, followed by the evaluation of motor function, the degree of SCI, the expression of HuR and RAD21, and neuronal-like apoptosis. The co-localization of HuR-RAD21, RAD21-NeuN, and NeuN-cleaved caspase 3 was measured by immunofluorescence. Additionally, targeting relationships among HuR, HDAC1, and RAD21 were verified by chromatin immunoprecipitation and RNA immunoprecipitation. After transfection, apoptosis of PC12 cells was tested by flow cytometry. Results showed that silencing HuR or up-regulating RAD21 could alleviate SCI and reduce neuronal apoptosis. HuR could combine HDAC1 mRNA, and HDAC1 combined the promoter of RAD21. Further experiments revealed that HuR enhanced HDAC1 expression and reduced RAD21 promoter region acetylation. Overexpression of RAD21 reversed the enhancement in apoptosis of PC12 cells caused by overexpression of HuR. The injection of HuR shRNA in tail vein of SCI rats increased basso, beattie, and bresnahan score, relieved SCI, reduced HuR and HDAC1 expression, elevated RAD21 expression, and decreased neuronal-like apoptosis. However, this result was reversed by co-injection of pcDNA3.1-HDAC1. In conclusion, down-regulation of HuR alleviated SCI and neuronal apoptosis in rats by suppressing HDAC1 expression and promoting RAD21 expression.

Hypoxia-induced lncRNA MRVI1-AS1 accelerates hepatocellular carcinoma progression by recruiting RNA-binding protein CELF2 to stabilize SKA1 mRNA

BACKGROUND

Long non-coding RNAs (lncRNAs) perform a vital role during the progression of hepatocellular carcinoma (HCC). Here, we aimed to identify a novel lncRNA involved in HCC development and elucidate the underlying molecular mechanism.

METHODS

The RT-qPCR and TCGA dataset analysis were applied to explore the expressions of MRVI1-AS1 in HCC tissues and cell lines. Statistical analysis was applied to analyze the clinical significance of MRVI1-AS1 in HCC. The functions of MRVI1-AS1 in HCC cells metastasis and growth were explored by transwell assays, wound healing assay, MTT assay, EdU assay, the intravenous transplantation tumor model, and the subcutaneous xenograft tumor model. Microarray mRNA expression analysis, dual luciferase assays, and actinomycin D treatment were used to explore the downstream target of MRVI1-AS1 in HCC cells. RIP assay was applied to assess the direct interactions between CELF2 and MRVI1-AS1 or SKA1 mRNA. Rescue experiments were employed to validate the functional effects of MRVI1-AS1, CELF2, and SKA1 on HCC cells.

RESULTS

MRVI1-AS1 was found to be dramatically upregulated in HCC and the expression was strongly linked to tumor size, venous infiltration, TNM stage, as well as HCC patients' outcome. Cytological experiments and animal experiments showed that MRVI1-AS1 promoted HCC cells metastasis and growth. Furthermore, SKA1 was identified as the downstream targeted mRNA of MRVI1-AS1 in HCC cells, and MRVI1-AS1 increased SKA1 expression by recruiting CELF2 protein to stabilize SKA1 mRNA. In addition, we found that MRVI1-AS1 expression was stimulated by hypoxia through a HIF-1-dependent manner, which meant that MRVI1-AS was a direct downstream target gene of HIF-1 in HCC.

CONCLUSION

In a word, our findings elucidated that hypoxia-induced MRVI1-AS1 promotes metastasis and growth of HCC cells via recruiting CELF2 protein to stabilize SKA1 mRNA, pointing to MRVI1-AS1 as a promising clinical application target for HCC therapy.

Small molecule targeting long noncoding RNA GAS5 administered intranasally improves neuronal insulin signaling and decreases neuroinflammation in an aged mouse model

Shifts in normal aging set stage for neurodegeneration and dementia affecting 1 in 10 adults. The study demonstrates that lncRNA GAS5 is decreased in aged and Alzheimer's disease brain. The role and targets of lncRNA GAS5 in the aging brain were elucidated using a GAS5-targeting small molecule NPC86, a frontier in lncRNA-targeting therapeutic. Robust techniques such as molecular dynamics simulation of NPC86 binding to GAS5, in vitro functional assays demonstrating that GAS5 regulates insulin signaling, neuronal survival, phosphorylation of tau, and neuroinflammation via toll-like receptors support the role of GAS5 in maintaining healthy neurons. The study demonstrates the safety and efficacy of intranasal NPC86 treatment in aged mice to improve cellular functions with transcriptomic analysis in response to NPC86. In summary, the study demonstrates that GAS5 contributes to pathways associated with neurodegeneration and NPC86 has tremendous therapeutic potential to prevent the advent of neurodegenerative diseases and dementias.

Regulation of Oxidative Stress by Long Non-coding RNAs in Central Nervous System Disorders

Central nervous system (CNS) disorders, such as ischemic stroke, Alzheimer’s disease, Parkinson’s disease, spinal cord injury, glioma, and epilepsy, involve oxidative stress and neuronal apoptosis, often leading to long-term disability or death. Emerging studies suggest that oxidative stress may induce epigenetic modifications that contribute to CNS disorders. Non-coding RNAs are epigenetic regulators involved in CNS disorders and have attracted extensive attention. Long non-coding RNAs (lncRNAs) are non-coding RNAs more than 200 nucleotides long and have no protein-coding function. However, these molecules exert regulatory functions at the transcriptional, post-transcriptional, and epigenetic levels. However, the major role of lncRNAs in the pathophysiology of CNS disorders, especially related to oxidative stress, remains unclear. Here, we review the molecular functions of lncRNAs in oxidative stress and highlight lncRNAs that exert positive or negative roles in oxidation/antioxidant systems. This review provides novel insights into the therapeutic potential of lncRNAs that mediate oxidative stress in CNS disorders.

Levels of lncRNA GAS5 in Plasma of Patients with Severe Traumatic Brain Injury: Correlation with Systemic Inflammation and Early Outcome

Scientific efforts continue to concentrate on elucidating the complex molecular mechanisms underlying traumatic brain injury (TBI), and recent reports suggest that epigenetic regulation including long non-coding RNA (lncRNA) is involved. The present study aimed to investigate the plasma concentration of a long non-coding RNA, named growth arrest-specific 5 (GAS5), in a group of 45 patients with severe TBI (sTBI), and to analyze the correlations of GAS5 with TBI onset, injury severity, systemic inflammation, and early outcome of the patients. It was found that plasma GAS5 levels were substantially increased in sTBI patients compared with the relative controls (p < 0.001). Further, significantly higher expression of plasma GAS5 was observed in patients with a Glasgow Coma Scale (GCS) score of less than five (p = 0.002) or unfavorable outcome at discharge (p < 0.001). Circulating GAS5 expression had a negative correlation with GCS score (r = −0.406, p = 0.006), and positive correlations with white blood cell count (r = 0.473, p = 0.001), neutrophil count (r = 0.502, p < 0.001), and neutrophil/lymphocyte ratio (NLR) (r = 0.398, p = 0.007). Univariate and multivariate logistic regression analyses revealed that GCS score (OR = 0.318, 95% CI 0.132−0.767, p = 0.011) and GAS5 (OR = 2.771, 95% CI 1.025−7.494, p = 0.045) were the two independent predictors for early outcome of patients. The receiver operating characteristic (ROC) curves showed good prognostic values of GCS score (AUC = 0.856, 95% CI: 0.719−0.943) and GAS5 expression (AUC = 0.798, 95% CI: 0.651−0.903). Importantly, the combined use of them can improve the prognostic ability of TBI with an AUC of 0.895 (95% CI: 0.767−0.966). Collectively, our study indicated that the levels of lncRNA GAS5 in circulation were elevated following severe TBI and correlated well with injury severity and inflammatory parameters. In addition, GAS5 as well as GCS scores may have the potential to predict the early outcome of TBI patients.

LncRNA GAS5 relates to Th17 cells and serves as a potential biomarker for sepsis inflammation, organ dysfunctions and mortality risk

BACKGROUND

Long noncoding RNA GAS5 (lnc-GAS5) is able to regulate macrophage M1 polarization and Th17 cell differentiation, also engaged in sepsis-induced inflammation and organ injury. This study aimed to further evaluate its linkage with Th1 cells and Th17 cells, as well as its clinical value in sepsis management.

METHODS

About 101 sepsis patients were enrolled followed by peripheral blood mononuclear cell (PBMC) and serum samples collection. PBMC lnc-GAS5 was detected by RT-qPCR; Th1 cells and Th17 cells in PBMC CD4⁺ T cells were detected by flow cytometry; serum IFN-γ and IL-17A were detected by ELISA. Besides, PBMC lnc-GAS5 was also detected in 50 health controls (HCs).

RESULTS

Lnc-GAS5 was reduced in sepsis patients than in HCs (p < 0.001), which also well-distinguished sepsis patients from HCs with AUC 0.860. Lnc-GAS5 did not relate to Th1 cells (p = 0.059) or IFN-γ (p = 0.192); while negatively linked with Th17 cells (p = 0.002) and IL-17A (p = 0.019) in sepsis patients. Interestingly, lnc-GAS5 negatively correlated with SOFA score (p = 0.001), SOFA-Respiratory system score (p = 0.001), SOFA-Coagulation score (p = 0.015), and SOFA-Renal system score (p = 0.026), but not SOFA-Liver score (p = 0.080), SOFA-Cardiovascular system score (p = 0.207) or SOFA-Nervous system score (p = 0.182) in sepsis patients. Furthermore, lnc-GAS5 was negatively related to CRP (p = 0.002) and APACHE II score (p = 0.004) in sepsis patients. Finally, lnc-GAS5 was decreased in dead sepsis patients compared to survivors (p = 0.007), which also distinguished sepsis deaths from survivors with AUC 0.713.

CONCLUSION

Lnc-GAS5 relates to Th17 cells and serves as a potential biomarker for sepsis severity and mortality risk.

Upregulated Long Non-coding RNA ALMS1-IT1 Promotes Neuroinflammation by Activating NF-κB Signaling in Ischemic Cerebral Injury

BACKGROUND

ALMS1-IT1, a recently identified lncRNA, has been proven to play a crucial role in regulating tumor progression and predicting the survival time of tumor patients. Data analysis from the Human Body Map (HBM) revealed that ALMS1-IT1 is expressed mainly in brain tissues.

METHODS

In this study, the role of ALMS1-IT in regulating neuro-inflammation and functional recovery was investigated after ischemic cerebral damage. To this end, the rat model of transient middle cerebral artery occlusion (tMCAO) was constructed, the cell model of oxygen-glucose deprivation (OGD) was established using BV2 microglial cells, and the aberrant expression of ALMS1-IT1 was assessed in brain tissues. After ALMS1- IT1 knockdown through intrathecal injection of Lv-shALMS1-IT1, neuro-inflammatory response and functional tests including a modified neurological severity score (mNSS) and a foot-fault test were assessed.

RESULTS

The level of ALMS1-IT1 was promptly enhanced at 12 hours (h) following MCAO, peaking at 48 h, and remaining high at day 14 compared to the sham group. Pro-inflammatory cytokines (IL-1β, IL-6, and TNF- α) were increased after MCAO, whereas ALMS1-IT1 inhibition suppressed the expression of IL-1β, IL-6 and TNF-α in MCAO rats. The results from mNSS and foot-fault test showed that ALMS1-IT1 knockdown significantly improved spatial learning and sensorimotor function of MCAO rats. Mechanistically, ALMS1-IT1 knockdown suppressed the activation of NF-κB signaling in vitro and in vivo, as evidenced by decreased p65 expression and p65 nuclear translocation. ALMS1-IT1 overexpression facilitated pro-inflammatory cytokines expression in microglia, whereas the effect was blocked by treatment with JSH-23 (a specific NF-κB inhibitor).

CONCLUSION

These data demonstrated that ALMS1-IT1 inhibition improved neurological function of MCAO rats, at least in part by repressing NF-κB-dependent neuro-inflammation.