LncRNA H19 Aggravates Cerebral Ischemia/Reperfusion Injury by Functioning as a ceRNA for miR-19a-3p to Target PTEN

Long non-coding RNAs H19 and NKILA are associated with the risk of death and lacunar stroke in the elderly population

INTRODUCTION

Differential expression of long non-coding RNAs (lncRNAs) is a hallmark of cardiovascular aging, cerebrovascular diseases, and neurodegenerative disorders. This research article investigates the association between a panel of lncRNAs and the risk of death and ischemic stroke in a cohort of non-institutionalized elderly subjects.

METHOD

A total of 361 healthy individuals aged 75 years old, prospectively recruited in the Vienna Transdanube Aging (VITA) cohort, were included. Expression of lncRNAs at baseline was assessed using quantitative polymerase chain reaction PCR with pre-amplification reaction, using 18S for normalization. The primary endpoint was all-cause mortality; the secondary endpoint was the incidence of new ischemic brain lesions. Death was assessed over a 14-year follow-up, and ischemic brain lesions were evaluated by magnetic resonance imaging (MRI) over a 90-month follow-up. Ischemic brain lesions were divided into large brain infarcts (Ø≥ 1.5 cm) or lacunes (Ø< 1.5 cm) RESULTS: The primary endpoint occurred in 53.5 % of the study population. The incidence of the secondary endpoint was 16 %, with a 3.3 % being large brain infarcts, and a 12.7 % lacunes. After adjustment for potential confounders, the lncRNA H19 predicted the incidence of the primary endpoint (HR 1.194, 95 % C.I. 1.012-1.409, p = 0.036), whereas the lncRNA NKILA was associated with lacunar stroke (HR 0.571, 95 % C.I. 0.375-0.868, p = 0.006).

CONCLUSION

In a prospective cohort of non-institutionalized elderly subjects, high levels of lncRNA H19 are associated with a higher risk of death, while low levels of lncRNA NKILA predict an increased risk of lacunar stroke.

Neuronal Responses to Ischemia: Scoping Review of Insights from Human-Derived In Vitro Models

Translation of neuroprotective treatment effects from experimental animal models to patients with cerebral ischemia has been challenging. Since pathophysiological processes may vary across species, an experimental model to clarify human-specific neuronal pathomechanisms may help. We conducted a scoping review of the literature on human neuronal in vitro models that have been used to study neuronal responses to ischemia or hypoxia, the parts of the pathophysiological cascade that have been investigated in those models, and evidence on effects of interventions. We included 147 studies on four different human neuronal models. The majority of the studies (132/147) was conducted in SH-SY5Y cells, which is a cancerous cell line derived from a single neuroblastoma patient. Of these, 119/132 used undifferentiated SH-SY5Y cells, that lack many neuronal characteristics. Two studies used healthy human induced pluripotent stem cell derived neuronal networks. Most studies used microscopic measures and established hypoxia induced cell death, oxidative stress, or inflammation. Only one study investigated the effect of hypoxia on neuronal network functionality using micro-electrode arrays. Treatment targets included oxidative stress, inflammation, cell death, and neuronal network stimulation. We discuss (dis)advantages of the various model systems and propose future perspectives for research into human neuronal responses to ischemia or hypoxia.

The Role of microRNAs in Epigenetic Regulation of Signaling Pathways in Neurological Pathologies

In recent times, there has been a significant increase in researchers' interest in the functions of microRNAs and the role of these molecules in the pathogenesis of many multifactorial diseases. This is related to the diagnostic and prognostic potential of microRNA expression levels as well as the prospects of using it in personalized targeted therapy. This review of the literature analyzes existing scientific data on the involvement of microRNAs in the molecular and cellular mechanisms underlying the development of pathologies such as Alzheimer's disease, cerebral ischemia and reperfusion injury, and dysfunction of the blood-brain barrier.

Endothelial plasticity across PTEN and Hippo pathways: A complex hormetic rheostat modulated by extracellular vesicles

Vascularization is a multifactorial and spatiotemporally regulated process, essential for cell and tissue survival. Vascular alterations have repercussions on the development and progression of diseases such as cancer, cardiovascular diseases, and diabetes, which are the leading causes of death worldwide. Additionally, vascularization continues to be a challenge for tissue engineering and regenerative medicine. Hence, vascularization is the center of interest for physiology, pathophysiology, and therapeutic processes. Within vascularization, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and Hippo signaling have pivotal roles in the development and homeostasis of the vascular system. Their suppression is related to several pathologies, including developmental defects and cancer. Non-coding RNAs (ncRNAs) are among the regulators of PTEN and/or Hippo pathways during development and disease. The purpose of this paper is to review and discuss the mechanisms by which exosome-derived ncRNAs modulate endothelial cell plasticity during physiological and pathological angiogenesis, through the regulation of PTEN and Hippo pathways, aiming to establish new perspectives on cellular communication during tumoral and regenerative vascularization.

A therapeutic role of exosomal lncRNA H19 from adipose mesenchymal stem cells in cutaneous wound healing by triggering macrophage M2 polarization

BACKGROUND

Emerging evidence has figured out that adipose mesenchymal stem cells (ADSCs) promote wound healing. Exosomes, which act as main paracrine factors and contains various protein, lncRNA, and miRNAs, play a critical role in wound healing. Nevertheless, the mechanism remains to be elucidated. This study aims to identify the underlying mechanism of ADSCs-derived exosome (ADSCs-exos)-mediated wound healing.

METHODS

ADSCs-exos were characterized using the transmission electron microscope, dynamic light scattering, and western blot. ELISA, RT-qPCR, flow cytometry, western blot, CCK-8 assay, transwell assay and tube formation were employed to validate the actions of ADSCs-exos harboring H19 in cell polarization, proliferation, migration and angiogenesis. The regulatory axis among H19, miR-130b-3p and PPARγ or STAT3 was confirmed by RNA pull-down, RIP assay and dual-luciferase reporter assays.

RESULTS

ADSCs-exos harboring H19 promoted macrophage M2 polarization, thereby enhancing fibroblast proliferation, migration and endothelial cell angiogenesis. However, their promotive effects were disrupted within H19 depletion in ADSCs-exos. Additionally, miR-130b-3p, directly targeting PPARγ or STAT3, was identified to be a downstream effector to participate in H19-mediated biological effects. Moreover, ADSCs-exos carrying H19 modulated cutaneous wound healing via H19/miR-130b-3p -mediated macrophage M2 polarization in vivo.

CONCLUSION

Collectively, ADSCs-derived exosomal H19 accelerates cutaneous wound healing via the miR-130b-3p/PPARγ/STAT3 axis, indicating potential therapeutic strategies for the treatment of wound healing.

Non-coding RNAs in stroke pathology, diagnostics, and therapeutics

Ischemic stroke is a leading cause of death and disability worldwide. Methods to alleviate functional deficits after ischemic stroke focus on restoration of cerebral blood flow to the affected area. However, pharmacological or surgical methods such as thrombolysis and thrombectomy have a narrow effective window. Harnessing and manipulating neurochemical processes of recovery may provide an alternative to these methods. Recently, non-coding RNA (ncRNA) have been increasingly investigated for their contributions to the pathology of diseases and potential for diagnostic and therapeutic applications. Here we will review several ncRNA - H19, MALAT1, ANRIL, NEAT1, pseudogenes, small nucleolar RNA, piwi-interacting RNA and circular RNA - and their involvement in stroke pathology. We also examine these ncRNA as potential diagnostic biomarkers, particularly in circulating blood, and as targets for therapeutic interventions. An important aspect of this is a discussion of potential methods of treatment delivery to allow for targeting of interventions past the blood-brain barrier, including lipid nanoparticles, polymer nanoparticles, and viral and non-viral vectors. Overall, several long non-coding RNA (lncRNA) discussed here have strong implications for the development of pathology and functional recovery after ischemic stroke. LncRNAs H19 and ANRIL show potential as diagnostic biomarkers, while H19 and MALAT1 may prove to be effective therapeutics for both minimising damage as well as promoting recovery. Other ncRNA have also been implicated in ischemic stroke but are currently too poorly understood to make inferences for diagnosis or treatment. Whilst the field of ncRNAs is relatively new, significant work has already highlighted that ncRNAs represent a promising novel investigative tool for understanding stroke pathology, could be used as diagnostic biomarkers, and as targets for therapeutic interventions.

[Long noncoding RNA ZEB1-AS1 aggravates cerebral ischemia/reperfusion injury in rats through the HMGB1/TLR-4 signaling axis]

OBJECTIVE

To investigate the role of long non-coding RNA ZEB1-AS1 in cerebral ischemia/reperfusion injury (CI/RI).

METHODS

We detected the temporal changes of ZEB1-AS1 and HMGB1 expression using qPCR and Western blotting in SD rats following CI/RI induced by middle cerebral artery occlusion (MCAO). The rat models of CI/RI were subjected to injections of vectors for ZEB1-AS1 overexpression or knockdown into the lateral ventricle, and the changes in cognitive function, brain water content, blood-brain barrier integrity, and IL-1β and TNF-α levels in the cerebrospinal fluid (CSF) and serum were observed. Neuronal loss and cell apoptosis in the cortex of the rat models were detected by FJC and TUNEL methods, and HMGB1 and TLR-4 expressions were analyzed with Western blotting. We also examined the effects of ZEB1-AS1 knockdown on apoptosis and expressions of HMGB1 and TLR-4 in SH-SY5Y cells with oxygen-glucose deprivation/reoxygenation (OGD/R).

RESULTS

In CI/RI rats, the expressions of ZEB1-AS1 and HMGB1 in the brain tissue increased progressively with the extension of reperfusion time, reaching the peak levels at 24 h followed by a gradual decline. ZEB1-AS1 overexpression significantly aggravated icognitive impairment and increased brain water content, albumin content in the CSF, and IL-1β and TNF-α levels in the CSF and serum in CI/RI rats (P < 0.05), while ZEB1-AS1 knockdown produced the opposite effects (P < 0.05 or 0.01). ZEB1-AS1 overexpression obviously increased the number of FJC-positive neurons in the cortex and enhanced the expressions of HMGB1 and TLR-4 in the rat models (P < 0.01); ZEB1-AS1 knockdown significantly reduced the number of FJC-positive neurons and lowered HMGB1 and TLR-4 expressions (P < 0.01). In SH-SY5Y cells with OGD/R, ZEB1-AS1 knockdown significantly suppressed cell apoptosis and lowered the expressions of HMGB1 and TLR-4 (P < 0.01).

CONCLUSION

ZEB1-AS1 overexpression aggravates CI/RI in rats through the HMGB1/TLR-4 signaling axis.

The multifaceted actions of the lncRNA H19 in cardiovascular biology and diseases

Cardiovascular diseases are the leading cause of death and debility worldwide. Various molecular mechanisms have been studied to better understand the development and progression of cardiovascular pathologies with hope to eradicate these diseases. With the advancement of the sequencing technology, it is revealed that the majority of our genome is non-coding. A growing body of literature demonstrates the critical role of long non-coding RNAs (lncRNAs) as epigenetic regulators of gene expression. LncRNAs can regulate cellular biological processes through various distinct molecular mechanisms. The abundance of lncRNAs in the cardiovascular system indicates their significance in cardiovascular physiology and pathology. LncRNA H19, in particular, is a highly evolutionarily conserved lncRNA that is enriched in cardiac and vascular tissue, underlining its importance in maintaining homeostasis of the cardiovascular system. In this review, we discuss the versatile function of H19 in various types of cardiovascular diseases. We highlight the current literature on H19 in the cardiovascular system and demonstrate how dysregulation of H19 induces the development of cardiovascular pathophysiology.

LncRNA SNHG14 is beneficial to oxygen glucose deprivation/reoxygenation-induced neuro-2a cell injury via mir-98-5p sequestration-caused BCL2L13 upregulation

BACKGROUND

The deregulation of long non-coding RNA (lncRNA) is associated with diverse human disorders, including cerebral ischemia/reperfusion injury (CI/RI). LncRNA SNHG14 was reported to function in CI/RI. Whereas, molecular mechanisms regulated by SNHG14 are not fully unveiled.

METHODS

Mice subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) were used as CI/RI animal models. Neuro-2a (N2A) cells subjected to oxygen glucose deprivation/reoxygenation (OGD/R) were used as CI/RI cell models. The expression of SNHG14, miR-98-5p and BCL2 like 13 (BCL2L13) was examined using quantitative real-time PCR (qPCR) or western blot. Apoptosis was monitored by flow cytometry assay. Apoptosis-related markers and endoplasmic reticulum (ER) stress-related markers were quantified by western blot. Inflammatory factors and oxidative stress were detected using matched commercial kits. The predicted relationship between miR-98-5p and SNHG14 or BCL2L13 was validated by dual-luciferase reporter assay, RIP assay and pull-down assay.

RESULTS

The high expression of SNHG14 was monitored in MCAO/R-treated mice and OGD/R-treated N2A cells. OGD/R-induced N2A cell apoptosis, ER stress, inflammation and oxidative stress were attenuated by SNHG14 knockdown. SNHG14 targeted miR-98-5p to positively regulate BCL2L13 expression. Inhibition of miR-98-5p recovered cell apoptosis, ER stress, inflammation and oxidative stress that were repressed by SNHG14 knockdown. Overexpression of BCL2L13 enhanced cell apoptosis, ER stress, inflammation and oxidative stress that were repressed by miR-98-5p enrichment.

CONCLUSIONS

SNHG14 knockdown alleviated OGD/induced N2A cell apoptosis, ER stress, inflammation and oxidative stress by depleting BCL2L13 via increasing miR-98-5p.

Network Pharmacology and Bioinformatics Methods Reveal the Mechanism of Berberine in the Treatment of Ischaemic Stroke

Aim

To elucidate the mechanism of action of berberine on ischaemic stroke based on network pharmacology, bioinformatics, and experimental verification.

Methods

Berberine-related long noncoding RNAs (lncRNAs) were screened from public databases. Differentially expressed lncRNAs in ischaemic stroke were retrieved from the Gene Expression Omnibus (GEO) database. GSE102541 was comprehensively analysed using GEO2R. The correlation between lncRNAs and ischaemic stroke was evaluated by the mammalian noncoding RNA-disease repository (MNDR) database. The component-target-disease network and protein-protein interaction (PPI) network of berberine in the treatment of ischaemic stroke were constructed by using network pharmacology. We then performed gene ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses. Finally, according to the molecular docking analysis and the binding probability between the lncRNA and key proteins, the effectiveness of the results was further verified by in vitro experiments.

Results

After matching stroke-related lncRNAs with berberine-related lncRNAs, four genes were selected as potential targets of berberine in the treatment of ischaemic stroke. Subsequently, lncRNA H19 was identified as the potential crucial regulatory lncRNA of berberine. Here, 52 target proteins of berberine in the treatment of ischaemic stroke were identified through database mining. Through topological analysis, 20 key targets were identified which were enriched in inflammation, apoptosis, and immunity. Molecular docking results showed that MAPK8, JUN, and EGFR were central genes. Finally, in vitro experiments demonstrated that lncRNA H19, p-JNK1/JNK1, p-c-Jun/c-Jun, and EGFR expressions were significantly increased in hypoxia-treated SH-SY5Y cells and were restored by berberine treatment.

Conclusion

The potential targets and biological effects of berberine in the treatment of ischaemic stroke were predicted in this study. The lncRNA H19/EGFR/JNK1/c-Jun signalling pathway may be a key mechanism of berberine-induced neuroprotection in ischaemic stroke.

Leonurus japonicus Houttuyn induces reactive oxygen species-mediated apoptosis via regulation of miR-19a-3p/PTEN/PI3K/AKT in U937 and THP-1 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Leonurus japonicus Houttuyn is a medicinal ingredient in more than 300 prescriptions in traditional Korean medicine. It is especially important for women's health and blood-related diseases. Recent research revealed that Leonurus japonicus Houttuyn extracts have antioxidative, anticancer, analgesic, anti-inflammatory, and neuroprotective properties.

AIM OF THE STUDY

However, its underlying anti-cancerous mechanisms remain unclear. This study elucidated the anticancer mechanism of Leonurus japonicus Houttuyn in U937 and THP-1 cancer cells.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was used for detecting main compound of Leonurus japonicus Houttuyn, rutin. EZ-Cytox cell viability assay, Western blot analysis, live and dead cell assay, 2', 7' dichlorofluorescin diacetate (DCFDA) assay, quantitative real-time PCR (qRT-PCR) analysis, and microRNA (miR) mimic transfection assay were applied to further investigate anti-cancer efficacies and underlying mechanism in U937 and THP-1 cells.

RESULTS

The main compound of Leonurus japonicus Houttuyn, rutin was detected using HPLC. The cytotoxic effect of Leonurus japonicus Houttuyn was exerted in U937 and THP-1 cancer cells but not in MDBK and IEC-6 normal cells. Leonurus japonicus Houttuyn decreased mitochondria membrane potential (ΔΨm). Consistently, Leonurus japonicus Houttuyn reduced the expression of survivin and cleaved caspase-9, caspase-3, and poly (ADP-ribose) polymerase (PARP). Cell death was increased in Leonurus japonicus Houttuyn treated groups. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and CCAAT-enhancer-binding protein homologous protein (CHOP) was increased and phosphatidylinositol-3-kinase (PI3K) and Protein kinase B (AKT) were decreased by Leonurus japonicus Houttuyn. Reactive oxygen speices generation was elevated by Leonurus japonicus Houttuyn and its cytotoxicity was reversed by N-acetyl-l-cysteine (NAC) pretreatment. Moreover, onco-microRNA (miR), miR-19a-3p was suppressed by Leonurus japonicus Houttuyn and transfection of miR-19a-3p mimic reversed the regulated PTEN, p-AKT, CHOP expression, attenuating Leonurus japonicus Houttuyn induced apoptosis.

CONCLUSIONS

These findings indicated that Leonurus japonicus Houttuyn has anti-cancer effects by regulation of PTEN/PI3K/AKT signal pathway and ROS-related ER stress-induced apoptosis via regulation of miR-19a-3p. Leonurus japonicus Houttuyn may be an effective candidate for triggering PTEN-dependent apoptosis of cancer cells related to acute myeloid leukemia.

An update on the functional roles of long non‑coding RNAs in ischemic injury (Review)

Ischemic injuries result from ischemia and hypoxia in cells. Tissues and organs receive an insufficient supply of nutrients and accumulate metabolic waste, which leads to the development of inflammation, fibrosis and a series of other issues. Ischemic injuries in the brain, heart, kidneys, lungs and other organs can cause severe adverse effects. Acute renal ischemia induces acute renal failure, heart ischemia induces myocardial infarction and cerebral ischemia induces cerebrovascular accidents, leading to loss of movement, consciousness and possibly, life-threatening disabilities. Existing evidence suggests that long non-coding RNAs (lncRNAs) are regulatory sequences involved in transcription, post-transcription, epigenetic regulation and multiple physiological processes. lncRNAs have been shown to be differentially expressed following ischemic injury, with the severity of the ischemic injury being affected by the upregulation or downregulation of certain types of lncRNA. The present review article provides an extensive summary of the functional roles of lncRNAs in ischemic injury, with a focus on the brain, heart, kidneys and lungs. The present review mainly summarizes the functional roles of lncRNA MALAT1, lncRNA MEG3, lncRNA H19, lncRNA TUG1, lncRNA NEAT1, lncRNA AK139328 and lncRNA CAREL, among which lncRNA MALAT1, in particular, plays a crucial role in ischemic injury and is currently a hot research topic.

Comprehensive Analysis of lncRNAs, miRNAs and mRNAs in Mouse Hippocampus With Hepatic Encephalopathy

Hepatic encephalopathy (HE) often presents with varying degrees of cognitive impairment. However, the molecular mechanism of its cognitive impairment has not been fully elucidated. Whole transcriptome analysis of hippocampus between normal and HE mice was performed by using RNA sequencing. 229 lncRNAs, 49 miRNAs and 363 mRNAs were differentially expressed in HE mice. The lncRNA-miRNA-mRNA interaction networks were established, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed. Dysregulated RNAs in interaction networks were mainly involved in synaptic plasticity and the regulation of learning and memory. In NH4Cl-treated hippocampal neurons, the dendritic spine density and maturity decreased significantly, the amplitude and frequency of mIPSC increased, while the amplitude and frequency of mEPSC decreased. These manifestations can be reversed by silencing SIX3OS1. Further research on these no-coding RNAs may lead to new therapies for the treatment and management of brain dysfunction caused by HE.

FTX Attenuates Cerebral Ischemia-Reperfusion Injury by Inhibiting Apoptosis and Oxidative Stress via miR-186-5p/MDM4 Pathway

LncRNA five prime to Xist (FTX) has been identified to exert a protective effect in multiple diseases. However, whether and how FTX attenuates cerebral ischemia-reperfusion injury (CI/RI) is still unclear. To simulate CI/RI, an in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) HT22 cell model and an in vivo middle cerebral artery occlusion/reperfusion (MCAO/R) Sprague-Dawley rat model were respectively constructed. In CI/RI plasma samples, OGD/R-challenged HT22 cells, and brain tissues from MCAO/R rats, FTX and mouse double minute 4 (MDM4) expressions were substantially decreased while miR-186-5p abundance was evidently increased. It was also revealed that FTX obviously improved neuronal damage induced by OGD/R through increasing proliferation, reducing apoptosis, and alleviating oxidative stress in OGD/R-challenged HT22 cells. Additionally, FTX positively regulated MDM4 level in OGD/R-treated HT22 cells as a sponge of miR-186-5p. Moreover, miR-186-5p upregulation or MDM4 suppression restored the inhibitory effects of FTX upregulation on OGD/R-triggered neuronal damage in HT22 cells. Therefore, these results suggest that FTX might ameliorate CI/RI by regulating the miR-186-5p/MDM4 pathway, providing a new target for stroke impairment treatment.

LncRNA NEAT1 ameliorate ischemic stroke via promoting Mfn2 expression through binding to Nova and activates Sirt3

BACKGROUND

Recent studies revealed that long non-coding RNAs (lncRNAs) have significant roles in regulating the pathogenesis of ischemia stroke, and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced cell apoptosis. Aberrant expression of NEAT1 was found after the injury of ischemia-reperfusion, but the mechanism was not fully understood.

METHODS

The expression of NEAT1 and Mfn2 were detected in BV-2 and N2a cell with or without OGD/R-induced by qRT-PCR. Inflammatory cytokines secretion was detected by enzyme-linked immunosorbent assay (ELISA). The oxidative stress was evaluated by the examination of ROS, MDA and SOD levels. Flow cytometry and apoptosis marker detection by western blot were performed to examined apoptosis.

RESULTS

The expression of NEAT1 and Mfn2 were decreased in OGD/R-induced cell model. Overexpression of NEAT1 or Mfn2 reduced oxidative stress and apoptosis by OGD/R-induced in neuronal cells, while knockdown of Sirt3 reversed the protective effect of NEAT1 and Mfn2. NEAT1 stabilized Mfn2 mRNA via recruiting Nova. NEAT1 alleviates the oxidative stress and apoptosis by OGD/R-induced via activating Sirt3.

CONCLUSION

LncRNA NEAT1 stabilizes Mfn2 mRNA via recruiting Nova, therefore increase the expression of Mfn2 and alleviates ischemia-reperfusion induced oxidative stress and apoptosis via Mfn2/Sirt3 pathway.

LncRNA H19 inhibits oxidative stress injury of cochlear hair cells by regulating miR-653-5p/SIRT1 axis

Oxidative stress is one of the important mechanisms of inner ear cell damage, which can lead to age-related hearing loss (ARHL). LncRNA H19 is significantly downregulated in the cochlea of old mouse, however, the role of H19 in the development of ARHL remains unclear. In this study, we aim to investigate the expression and function of H19 in oxidative stress injury of cochlear hair cells induced by HO. RT-qPCR and western blot analysis confirms that HEI-OC1 cells stimulated with HO decreases the expressions of H19 and SIRT1, but increases the expression of miR-653-5p. Overexpression of H19 could increase cell viability, ATP level and mitochondrial membrane potential, but reduce mitochondrial ROS generation and cell apoptosis ratio in HO-stimulated HEI-OC1 cells. MiR-653-5p is a target of H19, which can bind to the 3'-UTR of SIRT1. H19 is found to regulate the expression of SIRT1 through miR-653-5p. Further experiments demonstrates that H19 regulates HEI-OC1 cell viability, ATP level, mitochondrial membrane potential, mitochondrial ROS generation, and cell apoptosis ratio via the miR-653-5p/SIRT1 axis. In conclusion, lncRNA H19 inhibits oxidative stress injury of cochlear hair cells via the miR-653-5p/SIRT1 axis.

Long Non-Coding RNA-Mediated Competing Endogenous RNA Networks in Ischemic Stroke: Molecular Mechanisms, Therapeutic Implications, and Challenges

Ischemic stroke (IS) is a disease that is characterized by high mortality and disability. Recent studies have shown that LncRNA-mediated competing endogenous RNA (ceRNA) networks play roles in the occurrence and development of cerebral I/R injury by regulating different signaling pathways. However, no systematic analysis of ceRNA mechanisms in IS has been reported. In this review, we discuss molecular mechanisms of LncRNA-mediated ceRNA networks under I/R injury. The expression levels of LncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs) and their effects in four major cell types of the neurovascular unit (NVU) are also involved. We further summarize studies of LncRNAs as biomarkers and therapeutic targets. Finally, we analyze the advantages and limitations of using LncRNAs as therapeutics for IS.

Silencing of H19 alleviates oxygen-glucose deprivation/reoxygenation-triggered injury through the regulation of the miR-1306-5p/BCL2L13 axis

Cerebral ischemia/reperfusion (I/R) injury remains a leading cause of death and disability. Long noncoding RNAs (lncRNAs) exert key functions in cerebral I/R injury. Here, we sought to elucidate the mechanism underlying the regulation of H19 in cerebral I/R cell injury. An in vitro model of cerebral I/R injury was created using oxygen-glucose deprivation/reoxygenation (OGD/R). The levels of H19, miR-1306-5p and B cell lymphoma-2 (Bcl-2)-like 13 (BCL2L13) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability and apoptosis were determined by the Cell Counting-8 Kit (CCK-8) assay and flow cytometry, respectively. The levels of lactate dehydrogenase (LDH) and cytokines were evaluated by enzyme-linked immunosorbent assays (ELISA). Direct relationships among H19, miR-1306-5p and BCL2L13 were verified by dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pulldown assays. Our data showed that H19 and BCL2L13 were highly expressed in the cerebral I/R injury rats and OGD/R-triggered SK-N-SH and IMR-32 cells. The knockdown of H19 or BLC2L13 alleviated OGD/R-triggered injury in SK-N-SH and IMR-32 cells. Moreover, H19 silencing protected against OGD/R-triggered cell injury by down-regulating BCL2L13. H19 acted as a sponge of miR-1306-5p and BCL2L13 was a direct target of miR-1306-5p. H19 mediated BCL2L13 expression by sequestering miR-1306-5p. Furthermore, miR-1306-5p was a molecular mediator of H19 function. These results suggested that H19 silencing alleviated OGD/R-triggered I/R injury at least partially depending on the regulation of the miR-1306-5p/BCL2L13 axis.

Long non-coding RNA LOC366613 alleviates the cerebral ischemic injury via regulating the miR-532-5p/phosphatase and tensin homolog axis

Cerebral infarction (CI) has become a leading cause of death in China. Long non-coding RNAs (lncRNAs) are intensively involved in the progression of CI. Here, we aimed to investigate the effects of lncRNA LOC366613 (LOC366613) on cerebral I/R injury, as well as its possible mechanism. Transient middle cerebral artery occlusion (MCAO) was used to establish a mouse model of cerebral I/R, and the PC12 cell line was used to establish an in vitro oxygen-glucose deprivation (OGD) injury model. The MTT assay was used to determine cell viability, and qRT-PCR was used to determine RNA levels. Western blotting was conducted to detect protein expression levels. The TUNEL assay and flow cytometry were used to measure cell apoptosis, and 2,3,5-triphenyltetrazolium chloride (TTC) was used to determine cerebral infarct volume. Finally, RNA pull-down and luciferase activity assays were used to examine interactions between miR-532-5p and LOC366613, as well as between miR-532-5p and phosphatase and tensin homolog (PTEN). LOC366613 was overexpressed in patients with cerebral I/R injury. In PC12 cells, knockdown of LOC366613 reduced the apoptosis rate and lactic acid dehydrogenase (LDH) expression, while increasing cell viability. Moreover, miR-532-5p was shown to be a target of LOC366613, as predicted. Downregulation of miR-532-5p reversed the effects of LOC366613 knockdown on PC12 cell apoptosis, LDH release, and cell viability. Finally, PTEN was verified as a target of miR-532-5p. LOC366613 participates in cerebral I/R injury by regulating the miR-532-5p/PTEN axis, potentially providing a new CI treatment target.

Long non-coding RNA NORAD protects against cerebral ischemia/reperfusion injury induced brain damage, cell apoptosis, oxidative stress and inflammation by regulating miR-30a-5p/YWHAG

LncRNAs are identified as critical regulators in cerebral ischemia/reperfusion injury (CIRI). In this current work, SH-SY5Y cells suffered from oxygen-glucose deprivation/reperfusion (OGD/R) were applied to analyze the biological role of lncRNA NORAD and underlying molecular mechanism in CIRI in vitro. Levels of lncRNA NORAD, miR-30a-5p and YWHAG were measured using RT-qPCR. Bioinformatics analysis predicted the binding sites of lncRNA NORAD to miR-30a-5p and miR-30a-5p to YWHAG. Luciferase reporter assay verified the binding relationships among lncRNA NORAD, miR-30a-5p and YWHAG. Additionally, cell viability was determined using CCK-8 assay, and cell apoptosis was assessed using TUNEL staining and western blot analysis. Moreover, the levels of ROS, MDA, LDH and SOD as well as IL-1β, TNF-α, and IL-6 were assessed via application of the corresponding assay kits. Decreased cell viability and temporarily increased lncRNA NORAD level were observed in SH-SY5Y cells after OGD/R. It was demonstrated that lncRNA NORAD regulated YWHAG expression by sponging miR-30a-5p. Upregulation of lncRNA NORAD contributed to the enhancement of cell viability, the inhibition of cell apoptosis as well as the alleviation of oxidative stress and inflammation in OGD/R-injured SH-SY5Y cells, which were reversed upon elevation of miR-30a-5p. In contrast, downregulation of lncRNA NORAD reduced cell viability, promoted cell apoptosis as well as aggravated oxidative stress and inflammation under OGD/R challenge, and the functions of lncRNA NORAD knockdown in OGD/R injury were abolished by upregulation of YWHAG. Taken together, lncRNA NORAD exerted protective effects against OGD/R-induced neural injury by sponging miR-30a-5p to upregulate YWHAG expression.

The miRNome of Depression

Depression is an effect of complex interactions between genetic, epigenetic and environmental factors. It is well established that stress responses are associated with multiple modest and often dynamic molecular changes in the homeostatic balance, rather than with a single genetic factor that has a strong phenotypic penetration. As depression is a multifaceted phenotype, it is important to study biochemical pathways that can regulate the overall allostasis of the brain. One such biological system that has the potential to fine-tune a multitude of diverse molecular processes is RNA interference (RNAi). RNAi is an epigenetic process showing a very low level of evolutionary diversity, and relies on the posttranscriptional regulation of gene expression using, in the case of mammals, primarily short (17–23 nucleotides) noncoding RNA transcripts called microRNAs (miRNA). In this review, our objective was to examine, summarize and discuss recent advances in the field of biomedical and clinical research on the role of miRNA-mediated regulation of gene expression in the development of depression. We focused on studies investigating post-mortem brain tissue of individuals with depression, as well as research aiming to elucidate the biomarker potential of miRNAs in depression and antidepressant response.

Long non‑coding RNA XIST promotes cerebral ischemia/reperfusion injury by modulating miR‑27a‑3p/FOXO3 signaling

Cerebral ischemia/reperfusion (I/R) injury leads to neuronal damage, which may cause disability and even mortality. Multiple studies have revealed that long non‑coding RNAs (lncRNAs) serve pivotal roles in the pathogenesis of cerebral I/R injury. Therefore, the present study aimed to investigate whether the lncRNA X inactivate‑specific transcript (XIST) protects neuronal cells from cerebral I/R injury. In the present study, reverse transcription‑quantitative PCR demonstrated that XIST expression was upregulated in the brain tissues of an I/R mouse model and in oxygen and glucose deprivation/reperfusion (OGD/R)‑treated Neuro‑2a (N2a) cells. Knockdown of XIST alleviated cerebral injury, as well as reduced N2a cell apoptosis and reactive oxygen species (ROS) production. Additionally, luciferase reporter and RNA immunoprecipitation assays identified that XIST could bind with microRNA (miR)‑27a‑3p. It was found that miR‑27a‑3p expression was downregulated in the brain tissues of an I/R mouse model and in OGD/R‑induced N2a cells. In addition, miR‑27a‑3p overexpression attenuated I/R‑induced cerebral injury, and inhibited the apoptosis and ROS production of N2a cells. miR‑27a‑3p was found to target FOXO3. Silencing of FOXO3 alleviated cerebral injury, as well as inhibited N2a cell apoptosis and ROS production. Collectively, these findings indicated that XIST aggravated cerebral I/R injury by regulating miR‑27a‑3p/FOXO3 signaling, which may provide a novel insight into the treatment of cerebral I/R injury.

Long Non-coding RNA MEG3 Promotes Pyroptosis in Testicular Ischemia-Reperfusion Injury by Targeting MiR-29a to Modulate PTEN Expression

Increasing evidence shows that the abnormal long non-coding RNAs (lncRNAs) expression is closely related to ischemia-reperfusion injury (I/R) progression. Studies have previously described that lncRNA MEG3 regulates pyroptosis in various organs I/R. Nevertheless, the related mechanisms of MEG3 in testicular I/R has not been clarified. The aim of this research is to unravel underlying mechanisms of the regulation of pyroptosis mediated by MEG3 during testicular I/R. We have established a testicular torsion/detorsion (T/D) model and an oxygen-glucose deprivation/reperfusion (OGD/R)-treated spermatogenic cell model. Testicular ischemic injury was assessed by H&E staining. Western blotting, quantitative real-time PCR, MDA, and SOD tests and immunohistochemistry measured the expression of MEG3 and related proteins and the level of ROS production in testicular tissues. Quantitative real-time PCR and western blotting determined the relative expression of MEG3, miR-29a, and relevant proteins in GC-1. Cell viability and cytotoxicity were measured by CCK-8 and LDH assays. Secretion and expression levels of inflammatory proteins were determined by ELISA, immunofluorescence and western blotting. The interaction among MEG3, miR-29a, and PTEN was validated through a dual luciferase reporter assay and Ago2-RIP. In this research, we identified that MEG3 was upregulated in animal specimens and GC-1. In loss of function or gain of function assays, we verified that MEG3 could promote pyroptosis. Furthermore, we found that MEG3 negatively regulated miR-29a expression at the posttranscriptional level and promoted PTEN expression, and further promoted pyroptosis. Therefore, we explored the interaction among MEG3, miR-29a and PTEN and found that MEG3 directly targeted miR-29a, and miR-29a targeted PTEN. Overexpression of miR-29a effectively eliminated the upregulation of PTEN induced by MEG3, indicating that MEG3 regulates PTEN expression by targeting miR-29a. In summary, our research indicates that MEG3 contributes to pyroptosis by regulating miR-29a and PTEN during testicular I/R, indicating that MEG3 may be a potential therapeutic target in testicular torsion.

Long non-coding RNA H19: Physiological functions and involvements in central nervous system disorders

Central nervous system (CNS) disorders are some of the most complex and challenging diseases because of the intricate structure and functions of the CNS. Long non-coding RNA (LncRNA) H19, which had been mistaken for "transcription noise" previously, has now been found to be closely related to the development and homeostasis of the CNS. Several recent studies indicate that it plays an important role in the pathogenesis, treatment, and even prognosis of CNS disorders. LncRNA H19 is correlated with susceptibility to various CNS disorders such as intracranial aneurysms, ischemic stroke, glioma, and neuroblastoma. Moreover, it participates in the pathogenesis of CNS disorders by regulating transcription, translation, and signaling pathways, suggesting that it is a promising biomarker and therapeutic target for these disorders. This article reviews the functions and mechanisms of lncRNA H19 in various CNS disorders, including cerebral ischemia, cerebral hemorrhage, glioma, pituitary adenoma, neuroblastoma, Parkinson's disease, Alzheimer's disease, traumatic spinal cord injury, neuropathic pain, and temporal lobe epilepsy, to provide a theoretical basis for further research on the role of lncRNA H19 in CNS disorders.

Long noncoding RNA SOX2OT silencing alleviates cerebral ischemia-reperfusion injury via miR-135a-5p-mediated NR3C2 inhibition

OBJECTIVE

This study is aimed to investigate the role of the long noncoding RNA SOX2 overlapping transcript (SOX2OT) in cerebral ischemia-reperfusion injury (CIRI) and the underlying regulatory mechanisms.

METHODS

The oxygen-glucose deprivation/reoxygenation (OGD/R)-treated PC12 cells and middle cerebral artery occlusion/reperfusion (MCAO/R)-treated rats were established to simulate CIRI condition in vitro and in vivo. Quantitative real-time polymerase chain reaction was performed to detect the expression of SOX2OT, microRNA-135a-5p (miR-135a-5p), and nuclear receptor subfamily 3 group C member 2 (NR3C2). The cell viability and apoptosis were analyzed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assays. The levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS) or interleukin (IL)-1β and IL-6 were used to evaluate the oxidative stress or inflammation. Dual-luciferase reporter assay was conducted to validate the interactions among SOX2OT, miR-135a-5p, and NR3C2. Additionally, neurological deficit scores (NDS), infarct volume, and brain edema were used to assess brain impairments in vivo.

RESULTS

The expression of SOX2OT and NR3C2 was increased, while miR-135a-5p was decreased in OGD/R-treated PC12 cells. SOX2OT silencing repressed the levels of LDH, MDA, ROS, IL-1β, IL-6, reduced the numbers of TUNEL positive cells, and elevated viability and SOD level in OGD/R-treated PC12 cells. Besides, SOX2OT targeted miR-135a-5p, and miR-135a-5p targeted NR3C2. Both miR-135a-5p downregulation and NR3C2 upregulation reversed the suppressive effects of SOX2OT knockdown on oxidative stress, apoptosis, and inflammation of OGD/R-treated PC12 cells. Furthermore, injection of sh-SOX2OT reduced the NDS, cerebral infarct, and cerebral edema in MCAO/R-treated rats.

CONCLUSIONS

Silencing of SOX2OT attenuated CIRI via regulation of the miR-135a-5p/NR3C2 axis, which may provide a novel therapeutic target for CIRI.

Electroacupuncture promotes the recovery of rats with spinal cord injury by suppressing the Notch signaling pathway via the H19/EZH2 axis

Background

Spinal cord injury (SCI) is a life-changing event with an extremely poor prognosis. In our preliminary studies, electroacupuncture (EA) was found to promote the repair of SCI, which was closely related to the Notch signaling pathway. Therefore, in the present study, we hypothesized that EA protects against SCI by inhibiting the Notch signaling pathway and sought to investigate the underlying molecular mechanisms.

Methods

Rat and cell models of SCI were established. The expression of long non-coding RNA H19 was measured by real-time quantitative polymerase chain reaction. The expression levels of EZH2, Notch1, Notch3, Notch4, Hes1, and PS1 protein were measured by western blot. Cell apoptosis and viability were analyzed using flow cytometry and Cell Counting Kit-8 assays, respectively. The expressions of glial fibrillary acidic protein (GFAP) and nestin were detected by immunofluorescence staining.

Results

The expressions of H19, EZH2, and GFAP were significantly increased after SCI but were inhibited by EA; in contrast, nestin expression was significantly decreased by SCI but was restored by EA. Moreover, oxygen-glucose deprivation (OGD) treatment elevated the expression of H19, EZH2, and Notch-related factors as well as apoptosis in PC-12 cells, while suppressing cell viability. Suppressing H19 alleviated the effects of OGD on cell viability and apoptosis, and inhibited the expression of EZH2 and Notch-related factors expression; these effects were reversed by EZH2 overexpression. Finally, EA promoted the recovery of SCI rats and neural stem cell (NSC) proliferation by inhibiting the Notch signaling pathway, which was reversed by H19 overexpression.

Conclusions

Our results demonstrated that EA promotes the recovery of SCI rats and increases the proliferation and differentiation of NSCs by suppressing the Notch signaling pathway via modulating the H19/EZH2 axis.

Role of lncRNAs in the Development of Ischemic Stroke and Their Therapeutic Potential

Stroke is a major cause of premature mortality and disability around the world. Therefore, identification of cellular and molecular processes implicated in the pathogenesis and progression of ischemic stroke has become a priority. Long non-coding RNAs (lncRNAs) are emerging as significant players in the pathophysiology of cerebral ischemia. They are involved in different signalling pathways of cellular processes like cell apoptosis, autophagy, angiogenesis, inflammation, and cell death, impacting the progression of cerebral damage. Exploring the functions of these lncRNAs and their mechanism of action may help in the development of promising treatment strategies. In this review, the current knowledge of lncRNAs in ischemic stroke, focusing on the mechanism by which they cause cellular apoptosis, inflammation, and microglial activation, has been summarized. Very few lncRNAs have been functionally annotated. Therefore, the therapies based on lncRNAs still face many hurdles since the potential targets are likely to increase with the identification of new ones. Majority of experiments involving the identification and function of lncRNAs have been carried out in animal models, and the role of lncRNAs in human stroke presents a challenge. However, mitigating these issues through more rational experimental design might lead to the development of lncRNA-based stroke therapies to treat ischemic stroke.

Long non-coding RNA H19 expression and functional polymorphism rs217727 are linked to increased ischemic stroke risk

Background

Efforts to identify potential biomarkers for the diagnosis of ischemic stroke (IS) are valuable. The H19 gene plays a functional role in increasing the prevalence of IS risk factors. We evaluated the correlation between H19 rs217727 polymorphism and the expression level of H19 lncRNA with susceptibility to IS among the Iranian population.

Methods

Blood samples were collected from IS patients (n = 114) and controls (n = 114). We concentrated on the expression pattern of H19 at different time points (i.e., 0–24, 24–48, and 48–72 h after stroke). The tetra-amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) method was applied for DNA genotyping. We used the quantitative real-time PCR to evaluate H19 expression levels. We used the receiver operating characteristic (ROC) curve to evaluate the diagnosis and prognosis of IS.

Results

The rs217727polymorphism of H19 was related with IS susceptibility in the co-dominant (OR = 2.92, 95% CI = 0.91–10.92, P = 0.04) and recessive models (OR = 2.80, 95% CI = 0.96–8.15, P = 0.04). H19 expression was significantly upregulated in IS and remained high for 72 h after stroke. ROC curves showed that H19 expression within the first 24 h from stroke onset might serve as a biomarker for the early diagnosis of IS with 79.49% sensitivity and 80.00% specificity. H19 expression in small vessel occlusion (SVO) and large-artery atherosclerosis (LAA) patients were 3.74 and 3.34 times higher than the undetermined (UD) subtype, respectively [OR = 3.74 95% CL (1.14–12.27) P = 0.030 and OR = 3.34 95% CL (1.13–9.85) P = 0.029].

Conclusion

The rs217727 polymorphism of the H19 is correlated with IS susceptibility, and H19 expression levels were higher in SVO and LAA patients. The upregulation of H19 may be considered as a diagnostic biomarker in IS among the Iranian population, but it cannot serve as a useful prognostic marker.

MTMR14 protects against cerebral stroke through suppressing PTEN-regulated autophagy

The phosphoinositide phosphatase, myotubularinrelated protein 14 (MTMR14), plays a critical role in the regulating autophagy. However, its functional contribution to neuronal autophagy is still unclear. In the present study, we attempted to explore the effects of MTMR14 on ischemic stroke progression, as well as the underlying molecular mechanisms. Oxygen-glucose deprivation/reoxygenation (OGDR)-induced primary cortical neurons and pheochromocytoma (PC12) cells, and middle cerebral artery occlusion (MCAO)-operated mice were used to establish cerebral ischemia/reperfusion (I/R) injury in vitro and in vivo, respectively. OGDR treatment markedly decreased the expression of MTMR14 expression from mRNA and protein levels in the cultured primary neurons and PC12 cells. Functional analysis showed that OGDR-reduced cell viability was further accelerated by MTMR14 knockdown. On the contrary, MTMR14 over-expression significantly rescued the cell survival in OGDR-exposed cells. Moreover, autophagic markers including LC3BII and Beclin 1 were highly up-regulated in OGDR-incubated neurons and PC12 cells, while being further exacerbated by MTMR14 deletion. However, promoting MTMR14 dramatically alleviated LC3BII and Beclin 1 expression levels stimulated by OGDR. Importantly, we found that MTMR14-regulated autophagy was through its interactions with phosphatase and tensin homolog (PTEN). MTMR14 negatively modulated PTEN protein expression levels in OGDR-exposed cells. In vivo, MCAO-operated mice exhibited significantly reduced expression of MTMR14 in the ischemic penumbra tissues. After MCAO operation, MTMR14 over-expression effectively reduced infarct volume and neurological deficits scores, along with decreased activation of LC3B in neurons. Consistently, MCAO-increased PTEN, LC3BII and Beclin 1 were repressed by MTMR14 in mice. An interaction between MTMR14 and PTEN in response to MCAO was confirmed in vivo. Together, these results indicated the neuroprotective effects of MTMR14 on modulating PTEN-dependent excessive autophagy during cerebral I/R injury. Thus, targeting MTMR14 may provide feasible therapy for ischemic stroke onset and progression.