Long non-coding RNA H19 promotes leukocyte inflammation in ischemic stroke by targeting the miR-29b/C1QTNF6 axis

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury. We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement. However, the neural regeneration efficiency of induced neural stem cells remains limited. In this study, we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells. We found that H19 was the most downregulated neurogenesis-associated lncRNA in induced neural stem cells compared with induced pluripotent stem cells. Additionally, we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons. We predicted the target genes of H19 and discovered that H19 directly interacts with miR-325-3p, which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells. Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation, and miR-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition. Furthermore, H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells. Notably, silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice. Our results reveal that H19 regulates the neurogenesis of induced neural stem cells. H19 inhibition may promote the neural differentiation of induced neural stem cells, which is closely associated with neurological recovery following closed head injury.

Non-coding RNAs and Aquaporin 4: Their Role in the Pathogenesis of Neurological Disorders

Neurological disorders are a major group of non-communicable diseases affecting quality of life. Non-Coding RNAs (ncRNAs) have an important role in the etiology of neurological disorders. In studies on the genesis of neurological diseases, aquaporin 4 (AQP4) expression and activity have both been linked to ncRNAs. The upregulation or downregulation of several ncRNAs leads to neurological disorder progression by targeting AQP4. The role of ncRNAs and AQP4 in neurological disorders is discussed in this review.

Role of transcription factors, noncoding RNAs, epitranscriptomics, and epigenetics in post-ischemic neuroinflammation

Post-stroke neuroinflammation is pivotal in brain repair, yet persistent inflammation can aggravate ischemic brain damage and hamper recovery. Following stroke, specific molecules released from brain cells attract and activate central and peripheral immune cells. These immune cells subsequently release diverse inflammatory molecules within the ischemic brain, initiating a sequence of events, including activation of transcription factors in different brain cell types that modulate gene expression and influence outcomes; the interactive action of various noncoding RNAs (ncRNAs) to regulate multiple biological processes including inflammation, epitranscriptomic RNA modification that controls RNA processing, stability, and translation; and epigenetic changes including DNA methylation, hydroxymethylation, and histone modifications crucial in managing the genic response to stroke. Interactions among these events further affect post-stroke inflammation and shape the depth of ischemic brain damage and functional outcomes. We highlighted these aspects of neuroinflammation in this review and postulate that deciphering these mechanisms is pivotal for identifying therapeutic targets to alleviate post-stroke dysfunction and enhance recovery.

The Roles of Non-coding RNA Targeting Astrocytes in Cerebral Ischemia

Astrocytes are key targets for treating cerebral ischemia in the central nervous system. Non-coding RNAs (ncRNAs) participate in the pathological processes of astrocytes in cerebral ischemia. Recent reports suggest that ncRNAs ameliorate the outcome of cerebral ischemia by mediating astrocytes' inflammatory reaction, oxidative stress, excitotoxicity, autophagy, and apoptosis. Reconstructing cellular systems might offer a promising strategy for treating cerebral ischemia. This review briefly discusses the potential of ncRNAs as drug targets and explores the molecular regulatory mechanisms through which ncRNAs target astrocytes in cerebral ischemia. It provides an overview of the current research, discusses ncRNAs' implications as clinical markers for cerebral ischemia, and anticipates that ongoing research on ncRNAs may contribute to novel therapeutic approaches for treating this condition.

Expression, Functional Polymorphism, and Diagnostic Values of MIAT rs2331291 and H19 rs217727 Long Non-Coding RNAs in Cerebral Ischemic Stroke Egyptian Patients

Cerebral ischemic stroke (CIS) is a severe cerebral vascular event. This research aimed to evaluate the role of single-nucleotide polymorphisms (SNPs) of the lncRNAs MIAT rs2331291 and H19 rs217727 and epigenetic methylation in the expression patterns of serum lncRNA H19 in CIS Egyptian patients. It included 80 CIS cases and 40 healthy subjects. Serum MIAT expression levels decreased, whereas serum H19 expression levels increased among CIS compared to controls. For MIAT rs2331291, there were significant differences in the genotypic and allelic frequencies between the CIS and healthy subjects at p = 0.02 and p = 0.0001, respectively. Our findings illustrated a significantly increased MIAT T/T genotype frequency in hypertensive CIS compared to non-hypertensive CIS at p = 0.004. However, H19 rs217727 gene frequency C/C was not significantly higher in non-hypertensive CIS than in hypertensive CIS. The methylation of the H19 gene promoter was significantly higher in CIS patients compared to healthy subjects. The level of MIAT was positively correlated with serum H19 in CIS. Receiver operating characteristics (ROC) analysis revealed that serum MIAT and H19 have a high diagnostic potential for distinguishing CIS subjects from healthy ones. In conclusion, the MIAT-rs2331291 polymorphism might serve as a novel potential indicator of CIS.

Hemorheology and Inflammatory Marker Changes in Patients with Acute Ischemic Stroke after Intravenous Thrombolysis with Mechanical Thrombectomy

Objective

To investigate hemorheology and inflammatory marker changes after treatment for acute ischemic stroke (AIS) using intravenous thrombolysis (IVT) with mechanical thrombectomy (MT).

Methods

We retrospectively reviewed clinical records of patients with AIS (n=83) treated in The First Affiliated Hospital of Bengbu Medical College between January 2021 and December 2022 (n=83). The control group consisted of 38 patients who underwent IVT alone and the observation group consisted of 45 patients who underwent IVT with MT. We compared differences in mean variables related to hemorheology, inflammatory markers, and total efficacy between the two groups.

Results

We found that hemorheology values (plasma viscosity [PV], whole blood viscosity [WBV], fibrinogen [FIB], and hematocrit [HCT]), and the levels of inflammatory markers (tumor necrosis factor ɑ [TNF-ɑ] and interleukin-6 [IL-6]) were higher in the control group than in the observation group after treatment (P<0.05). In addition, the total efficacy of the observation group (93.3%) was higher than that in the control group (76.3%; P=0.016).

Conclusions

The clinical efficacy of combined IVT and MT in the treatment of AIS is superior to IVT alone, improving levels of hemorheology and inflammatory markers in patients with AIS.

ANRIL, H19 and TUG1: a review about critical long non-coding RNAs in cardiovascular diseases

Cardiovascular diseases are the leading cause of death worldwide. They are non-transmissible diseases that affect the cardiovascular system and have different etiologies such as smoking, lipid disorders, diabetes, stress, sedentary lifestyle and genetic factors. To date, lncRNAs have been associated with increased susceptibility to the development of cardiovascular diseases such as hypertension, acute myocardial infarction, stroke, angina and heart failure. In this way, lncRNAs are becoming a very promising point for the prevention and diagnosis of cardiovascular diseases. Therefore, this review highlights the most important and recent discoveries about the mechanisms of action of the lncRNAs ANRIL, H19 and TUG1 and their clinical relevance in these pathologies. This may contribute to early detection of cardiovascular diseases in order to prevent the pathological phenotype from becoming established.

LncRNAs: Promising Therapeutic Targets and Biomarkers for Ischemic Stroke

Ischemic stroke is one of the leading causes of mortality and disability worldwide. Currently, options for ischemic stroke clinical therapy remain limited to intravenous thrombolysis and thrombectomy, which can only be applied to a minority of patients due to narrow therapeutic time window. Therefore, the discovery of new therapeutic targets and biomarkers is of great significance for ischemic stroke therapy. Long non-coding RNAs (lncRNAs) are the most extensive ncRNA transcripts and play critical roles in different kinds of diseases. Accumulative evidence suggests that lncRNAs are widely involved in multiple pathophysiological processes of ischemic stroke, highlighting their potential role as ischemic stroke therapeutic targets. Moreover, the significantly altered expression of lncRNAs in circulation of ischemic stroke patients reveals that they may serve as diagnostic, therapeutic, and prognosis biomarkers for ischemic stroke. In this commentary, we provide an overview of the roles of lncRNAs in the pathophysiology of ischemic stroke and discuss the opportunities of lncRNAs in the diagnosis and treatment of ischemic stroke. In addition, the challenges for the clinical translation of lncRNAs in ischemic stroke are also discussed.

The role of long noncoding ribonucleic acids in the central nervous system injury

Central nervous system (CNS) injury involves complex pathophysiological molecular mechanisms. Long noncoding ribonucleic acids (lncRNAs) are an important form of RNA that do not encode proteins but take part in the regulation of gene expression and various biological processes. Multitudinous studies have evidenced lncRNAs to have a significant role in the process of progression and recovery of various CNS injuries. Herein, we review the latest findings pertaining to the role of lncRNAs in CNS, both normal and diseased state. We aim to present a comprehensive clinical application prospect of lncRNAs in CNS, and thus, discuss potential strategies of lncRNAs in treating CNS injury.

Neuroinflammatory Biomarkers in the Brain, Cerebrospinal Fluid, and Blood After Ischemic Stroke

The most frequent type of stroke, known as ischemic stroke (IS), is a significant global public health issue. The pathological process of IS and post-IS episodes has not yet been fully explored, but neuroinflammation has been identified as one of the key processes. Biomarkers are objective indicators used to assess normal or pathological processes, evaluate responses to treatment, and predict outcomes, and some biomarkers can also be used as therapeutic targets. After IS, various molecules are produced by different cell types, such as microglia, astrocytes, infiltrating leukocytes, endothelial cells, and damaged neurons, that participate in the neuroinflammatory response within the ischemic brain region. These molecules may either promote or inhibit neuroinflammation and may be released into extracellular spaces, including cerebrospinal fluid (CSF) and blood, due to reasons such as BBB damage. These neuroinflammatory molecules should be valued as biomarkers to monitor whether their expression levels in the blood, CSF, and brain correlate with the diagnosis and prognosis of IS patients or whether they have potential as therapeutic targets. In addition, although some molecules do not directly participate in the process of neuroinflammation, they have been reported to have potential diagnostic or therapeutic value against post-IS neuroinflammation, and these molecules will also be listed. In this review, we summarize the neuroinflammatory biomarkers in the brain, CSF, and blood after an IS episode and the potential value of these biomarkers for the diagnosis, treatment, and prognosis of IS patients.

Dysregulation of Circulatory Levels of lncRNAs in Parkinson's Disease

Emerging evidence suggested that long non-coding RNAs (lncRNAs) were involved in Parkinson's disease (PD) pathogenesis. Herein, we used gene expression profiles from GEO database to construct a PD-specific ceRNA network. Functional enrichment analysis suggested that ceRNA network might participate in the development of PD. PPI networks were constructed, and the ceRNA subnetwork based on five hub genes was set up. In a cohort of 32 PD patients and 31 healthy controls, the expression of 10 DElncRNAs (TTC3-AS1, LINC01259, ZMYND10-AS1, CHRM3-AS1, MYO16-AS1, AGBL5-IT1, HOTAIRM1, RABGAP1L-IT1, HLCS-IT1, and LINC00393) were further verified. Consistent with the microarray data, LINC01259 expression was significantly lower in PD patients compared with controls (P = 0.008). Intriguingly, such a difference was only observed among male patients and male controls when dividing study participants based on their gender (P = 0.016). However, the expression of other lncRNAs did not differ significantly between the two groups. Receiver operating characteristic (ROC) curve analysis revealed that the diagnostic power of LINC01259 was 0.694 for PD and 0.677 for early-stage PD. GSEA enrichment analysis revealed that LINC01259 was mainly enriched in biological processes associated with immune function and inflammatory response. Moreover, LINC01259 expression was not correlated with age of patients, disease duration, disease stage, MDS-UPDRS score, MDS-UPDRS III score, MMSE score, and MOCA score. The current study provides further evidence for the dysregulation of lncRNAs in circulating leukocytes of PD patients, revealing that LINC01259 has clinical potential as a novel immune and inflammatory biomarker for PD and early-stage PD diagnosis.

Circulating MicroRNAs and Extracellular Vesicle-Derived MicroRNAs as Predictors of Functional Recovery in Ischemic Stroke Patients: A Systematic Review and Meta-Analysis

Stroke accounts for the second leading cause of death and a major cause of disability, with limited therapeutic strategy in both the acute and chronic phases. Blood-based biomarkers are intensively researched and widely recognized as useful tools to predict the prognoses of patients confronted with therapeutically limited diseases. We performed a systematic review of the circulating biomarkers in IS patients with prognostic value, with a focus on microRNAs and exosomes as predictive biomarkers of motor and cognitive recovery. We identified 63 studies, totalizing 72 circulating biomarkers with prognostic value in stroke recovery, as follows: 68 miRNAs and exosomal-miRNAs being identified as predictive for motor recovery after stroke, and seven biomarkers being predictive for cognitive recovery. Twelve meta-analyses were performed using effect sizes (random-effects and fixed-effects model). The most significant correlation findings obtained after pooling were with miR-21, miR-29b, miR-125b-5p, miR-126, and miR-335. We identified several miRNAs that were correlated with clinical outcomes of stroke severity and recovery after ischemic stroke, providing predictive information on motor and cognitive recovery. Based on the current state of research, we identified serum miR-9 and neutrophil miR-29b as the most promising biomarkers for in-depth follow-up studies, followed by serum miR-124 and plasma miR-125b.

The Association between High Mobility Group Box 1 and Stroke-Associated Pneumonia in Acute Ischemic Stroke Patients

Objective: This study aimed to investigate the association between high-mobility-group box 1 (HMGB1) and stroke-associated pneumonia (SAP) in acute ischemic stroke (AIS) patients. Methods: AIS patients were enrolled in two centers. The serum samples were collected within the first 24 h after admission, and HMGB1 levels were measured by enzyme-linked immunosorbent assay. Logistic regression models were used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) of SAP for HMGB1 concentrations. Restricted cubic splines (RCS) were performed to explore the shapes of the association between HMGB1 concentrations and SAP. Results: From January 2022 to May 2022, a total of 420 AIS patients were enrolled. Ninety-six (22.9%) patients develop SAP. The levels of HMGB1 in the SAP group were higher than those in the non-SAP group (p < 0.001). Using the first quartile of HMGB1 group as a reference, patients in the fourth quartile of HMGB1 group had the highest likelihood of experiencing SAP in the unadjusted model (OR = 3.687; 95% CI: 1.851−7.344), age- and sex-adjusted model (OR = 3.511; 95% CI: 1.725−7.147), and multivariable-adjusted model (OR = 2.701; 95% CI: 1.045−6.981). HMGB1 was also independently associated with SAP as a continuous variable in the unadjusted model (OR = 1.132; 95% CI: 1.069−1.199), age- and sex-adjusted model (OR = 1.131; 95% CI: 1.066−1.200), and multivariable-adjusted model (OR = 1.096; 95% CI: 1.011−1.188). RCS showed a linear association between HMGB1 and SAP (p for linear trend = 0.008) Conclusions: HMGB1 might be able to act as a potential biomarker of SAP in AIS patients.

Epigenetic mechanisms and potential therapeutic targets in stroke

Accumulating evidence indicates a central role for epigenetic modifications in the progression of stroke pathology. These epigenetic mechanisms are involved in complex and dynamic processes that modulate post-stroke gene expression, cellular injury response, motor function, and cognitive ability. Despite decades of research, stroke continues to be classified as a leading cause of death and disability worldwide with limited clinical interventions. Thus, technological advances in the field of epigenetics may provide innovative targets to develop new stroke therapies. This review presents the evidence on the impact of epigenomic readers, writers, and erasers in both ischemic and hemorrhagic stroke pathophysiology. We specifically explore the role of DNA methylation, DNA hydroxymethylation, histone modifications, and epigenomic regulation by long non-coding RNAs in modulating gene expression and functional outcome after stroke. Furthermore, we highlight promising pharmacological approaches and biomarkers in relation to epigenetics for translational therapeutic applications.

Neutrophilic noncoding RNAs predict outcomes of acute ischemic stroke patients treated with recombinant tissue plasminogen activator

There’s no evidence demonstrating the association between noncoding RNAs levels before IV recombinant tissue plasminogen activator (rtPA) administration and the outcomes of acute ischemic stroke (AIS). 145 AIS patients received rtPA treatment were recruited at the stroke center from 2018 to 2019, and 103 patients were included in this study. A panel of noncoding RNAs (miRNA-23a, miRNA-193a, miRNA-128, miRNA-99a, miRNA-let-7a, miRNA-494, miRNA-424, and lncRNA H19) were measured in the circulating neutrophils of AIS patients before rtPA treatment. Endpoints included excellent outcome (modified Rankin Scale score [mRS] 0–1) or poor outcome (mRS &gt; 1) at 3 months and symptomatic intracerebral hemorrhage (sICH) after rtPA treatment. Among the eight noncoding RNAs detected in circulating neutrophils of the 103 participants, miRNA-23a levels were associated with the stroke severity on admission and symptom progression at 24 h after rtPA treatment. A noncoding RNA score composed of miRNA-23a, miRNA-99a, and lncRNA H19 was screened to predict the functional outcome at 3 months and the incidence of sICH after rtPA treatment. In the logistic regression analysis, the noncoding RNA score ≥ −0.336 (OR = 2.862 [1.029–7.958], p = 0.044) was an independent predictor of the poor outcome at 3 months after adjustment of clinical variables, the addition of the noncoding RNA score to the clinical model improved the discrimination (IDI% = 4.68 [0.65–8.71], p = 0.020), as well as the net reclassification (NRI% = 33.04 [0.54–71.49], p = 0.016). The noncoding RNA score ≥ −0.336 (OR = 5.250 [1.096–25.135], p = 0.038) was also independently predicted the sICH, the addition of the noncoding RNA score to the clinical variables improved discrimination and reclassification as well. The noncoding RNA score was also associated with the infarct volume and symptom improvement at 7 days after rtPA treatment. In conclusion, a higher neutrophilic noncoding RNA score provides predictive value to identify AIS patients with worse outcomes after rtPA treatment. miRNA-23a, miRNA-99a, and lncRNA H19 are worth further investigation for their effects in thrombolysis after AIS.

MicroRNA-29b Suppresses Inflammation and Protects Blood-Brain Barrier Integrity in Ischemic Stroke

Objectives. Following cerebral ischemia, microRNA- (miR-) 29b in circulating blood is downregulated. This study investigates the underlying mechanism and implications of miR-29b in leukocyte induction. Methods. miR-29b from stroke patients and rats with middle cerebral artery occlusion (MCAO) were assessed using real-time polymerase chain reaction (PCR). miR-29b agomir was used to increase miR-29b expression in leukocytes via intravenous injection. C1q and tumor necrosis factor (C1QTNF) 6, interleukin- (IL-) 1β, zonula occludens- (ZO-) 1, occludin, and ischemic outcomes were assessed in MCAO rats. Additionally, hCMEC/D3 cells were subjected to oxygen–glucose deprivation (OGD) and cocultured with HL-60 cells. Results. miR-29b levels in neutrophils were found to be significantly lower in stroke patients compared with healthy controls, which may indicate its high diagnostic sensitivity and specificity for stroke. Moreover, miR-29b levels in leukocytes showed a negative correlation with National Institute of Health Stroke Scale (NIHSS) scores and C1QTNF6 levels. In MCAO rats, miR-29b overexpression reduced brain infarct volume and brain edema, decreasing IL-1β levels in leukocytes and in the brain 24 hours poststroke. miR-29b attenuated IL-1β expression via C1QTNF6 inhibition, leading to decreased blood-brain barrier (BBB) disruption and leukocyte infiltration. Moreover, miR-29b overexpression in HL-60 cells downregulated OGD-induced hCMEC/D3 cell apoptosis and increased ZO-1 and occludin levels in vitro. Conclusion. Leukocytic miR-29b attenuates inflammatory response by augmenting BBB integrity through C1QTNF6, suggesting a novel miR-29b-based therapeutic therapy for ischemic stroke.