Circulating MicroRNAs in Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage

Extracellular Vesicle-Enriched miRNA-Biomarkers Show Improved Utility for Detecting Alzheimer's Disease Dementia and Medial Temporal Atrophy

Background

Emerging diagnostic modalities suggest that miRNA profiles within extracellular vesicles (EVs) isolated from peripheral blood specimens may provide a non-invasive diagnostic alternative for dementia and neurodegenerative disorders. Given that EVs confer a protective environment against miRNA enzymatic degradation, the miRNAs enriched in the EV fraction of blood samples could serve as more stable and clinically relevant biomarkers compared to those obtained from serum.

Objective

To compare miRNAs isolated from EVs versus serum in blood taken from Alzheimer's disease (AD) dementia patients and control cohorts.

Methods

We compared 25 AD patients to 34 individuals who exhibited no cognitive impairments (NCI). Subjects were Singapore residents with Chinese heritage. miRNAs purified from serum versus blood-derived EVs were analyzed for associations with AD dementia and medial temporal atrophy detected by magnetic resonance imaging.

Results

Compared to serum-miRNAs, we identified almost twice as many EV-miRNAs associated with AD dementia, and they also correlated more significantly with medial temporal atrophy, a neuroimaging marker of AD-brain pathology. We further developed combination panels of serum-miRNAs and EV-miRNAs with improved performance in identifying AD dementia. Dominant in both panels was miRNA-1290.

Conclusions

This data indicates that miRNA profiling from EVs offers diagnostic superiority. This underscores the role of EVs as vectors harboring prognostic biomarkers for neurodegenerative disorders and suggests their potential in yielding novel biomarkers for AD diagnosis.

Biomarkers in aneurysmal subarachnoid hemorrhage: A short review

Poor outcomes of aneurysmal subarachnoid hemorrhage (aSAH) can be the result of the initial catastrophic event or the many acute or delayed neurological complications. Recent evidence suggests that some molecules play a critical role in both events, through some unknown pathways involved. Understanding the role of these molecules in these events could allow to improve diagnostic accuracy, guide management, and prevent long-term disability in aSAH. Here we present the studies on aSAH biomarkers present in current medical literature, highlighting their roles and main results.

Development and validation of urinary exosomal microRNA biomarkers for the diagnosis of acute rejection in kidney transplant recipients

Introduction

Acute rejection (AR) continues to be a significant obstacle for short- and long-term graft survival in kidney transplant recipients. Herein, we aimed to examine urinary exosomal microRNAs with the objective of identifying novel biomarkers of AR.

Materials and methods

Candidate microRNAs were selected using NanoString-based urinary exosomal microRNA profiling, meta-analysis of web-based, public microRNA database, and literature review. The expression levels of these selected microRNAs were measured in the urinary exosomes of 108 recipients of the discovery cohort using quantitative real-time polymerase chain reaction (qPCR). Based on the differential microRNA expressions, AR signatures were generated, and their diagnostic powers were determined by assessing the urinary exosomes of 260 recipients in an independent validation cohort.

Results

We identified 29 urinary exosomal microRNAs as candidate biomarkers of AR, of which 7 microRNAs were differentially expressed in recipients with AR, as confirmed by qPCR analysis. A three-microRNA AR signature, composed of hsa-miR-21-5p, hsa-miR-31-5p, and hsa-miR-4532, could discriminate recipients with AR from those maintaining stable graft function (area under the curve [AUC] = 0.85). This signature exhibited a fair discriminative power in the identification of AR in the validation cohort (AUC = 0.77).

Conclusion

We have successfully demonstrated that urinary exosomal microRNA signatures may form potential biomarkers for the diagnosis of AR in kidney transplantation recipients.

FAS-mediated circRNA-miRNA-mRNA Crosstalk Network Regulates Immune Cell Infiltration in Cerebral Infarction

New data are accumulating on the involvement of interaction among circular RNAs (circRNAs), microRNAs (miRNAs/miRs), and messenger RNAs (mRNAs) in cerebral infarction (CI). This study aims to illustrate the GEO database-based identification of a circRNA-miRNA-mRNA crosstalk network underlying immune cell infiltration in CI. The differential analysis suggested that 1696 circRNAs, 1989 miRNAs, and 5550 mRNAs that were differentially expressed in CI samples were retrieved from GEO database. GO and KEGG functional enrichment analyses showed that the differentially expressed mRNAs were mainly associated with common risk factors of CI, such as immune and inflammatory response. Next, the circRNA-miRNA pairs and miRNA-mRNA pairs were predicted, and the circRNA-miRNA-mRNA network was constructed by Cytoscape software. Totally, 436 circRNA-miRNA pairs were obtained through the online database, and 2033 miRNA-mRNA pairs were used to construct the circRNA-miRNA-mRNA crosstalk network. A protein-protein interaction (PPI) network was constructed on the basis of the ceRNA network, followed by key gene identification in the GSE9877 dataset. FAS was identified as the key gene in CI. The constructed FAS-mediated circRNA-miRNA-mRNA crosstalk network included five upregulated circRNAs (hsa_circ_0075341, hsa_circ_0049637, hsa_circ_0001085, hsa_circ_0004808 and hsa_circ_0092337) and five downregulated miRNAs (hsa-miR-92a-2-5p, hsa-miR-1245b-3p, hsa-miR-592, hsa-miR-224-5p, and hsa-miR-30e-3p). Furthermore, the CIBERSORT algorithm indicated that FAS was associated with immune cell infiltration in CI. In conclusion, this study revealed a role for FAS-centered circRNA-miRNA-mRNA crosstalk network in regulating immune cell infiltration of CI, which may be a viable target for CI prevention.

MicroRNA cerebrospinal fluid profile during the early brain injury period as a biomarker in subarachnoid hemorrhage patients

Introduction

Delayed cerebral ischemia (DCI) is a dreadful complication present in up to 30% of patients with spontaneous subarachnoid hemorrhage (SAH). Indeed, DCI is one of the main causes of long-term disability in SAH, yet its prediction and prevention are troublesome in poor-grade SAH cases. In this prospective study, we explored the potential role of micro ribonucleic acid (microRNA, abbreviated miRNAs)-small non-coding RNAs involved in clue gene regulation at the post-transcriptional level-as biomarkers of neurological outcomes in SAH patients.

Methods

We analyzed the expression of several miRNAs present in the cerebrospinal fluid (CSF) of SAH patients during the early stage of the disease (third-day post-hemorrhage). NanoString Technologies were used for the characterization of the CSF samples.

Results

We found an overexpression of miRNAs in the acute stage of 57 SAH in comparison with 10 non-SAH controls. Moreover, a differential expression of specific miRNAs was detected according to the severity of clinical onset, but also regarding the development of DCI and the midterm functional outcomes.

Conclusion

These observations reinforce the potential utility of miRNAs as prognostic and diagnostic biomarkers in SAH patients. In addition, the identification of specific miRNAs related to SAH evolution might provide insights into their regulatory functions of pathophysiological pathways, such as the TGF-β inflammatory pathway and blood-brain barrier disruption.

The circRNA-miRNA/RBP regulatory network in myocardial infarction

Myocardial infarction (MI) is a serious heart disease that causes high mortality rate worldwide. Noncoding RNAs are widely involved in the pathogenesis of MI. Circular RNAs (circRNAs) are recently validated to be crucial modulators of MI. CircRNAs are circularized RNAs with covalently closed loops, which make them stable under various conditions. CircRNAs can function by different mechanisms, such as serving as sponges of microRNAs (miRNAs) and RNA-binding proteins (RBPs), regulating mRNA transcription, and encoding peptides. Among these mechanisms, sponging miRNAs/RBPs is the main pathway. In this paper, we systematically review the current knowledge on the properties and action modes of circRNAs, elaborate on the roles of the circRNA-miRNA/RBP network in MI, and explore the value of circRNAs in MI diagnosis and clinical therapies. CircRNAs are widely involved in MI. CircRNAs have many advantages, such as stability, specificity, and wide distribution, which imply that circRNAs have a great potential to act as biomarkers for MI diagnosis and prognosis.

MiR-1290: a potential therapeutic target for regenerative medicine or diagnosis and treatment of non-malignant diseases

MicroRNAs are a set of small non-coding RNAs that could change gene expression with post-transcriptional regulation. MiRNAs have a significant role in regulating molecular signaling pathways and innate and adaptive immune system activity. Moreover, miRNAs can be utilized as a powerful instrument for tissue engineers and regenerative medicine by altering the expression of genes and growth factors. MiR-1290, which was first discovered in human embryonic stem cells, is one of those miRNAs that play an essential role in developing the fetal nervous system. This review aims to discuss current findings on miR-1290 in different human pathologies and determine whether manipulation of miR-1290 could be considered a possible therapeutic strategy to treat different non-malignant diseases. The results of these studies suggest that the regulation of miR-1290 may be helpful in the treatment of some bacterial (leprosy) and viral infections (HIV, influenza A, and Borna disease virus). Also, adjusting the expression of miR-1290 in non-infectious diseases such as celiac disease, necrotizing enterocolitis, polycystic ovary syndrome, pulmonary fibrosis, ankylosing spondylitis, muscle atrophy, sarcopenia, and ischemic heart disease can help to treat these diseases better. In addition to acting as a biomarker for the diagnosis of non-malignant diseases (such as NAFLD, fetal growth, preeclampsia, down syndrome, chronic rhinosinusitis, and oral lichen planus), the miR-1290 can also be used as a valuable instrument in tissue engineering and reconstructive medicine. Consequently, it is suggested that the regulation of miR-1290 could be considered a possible therapeutic target in the treatment of non-malignant diseases in the future.

Long non-coding RNAs mediate cerebral vascular pathologies after CNS injuries

Central nervous system (CNS) injuries are one of the leading causes of morbidity and mortality worldwide, accompanied with high medical costs and a decreased quality of life. Brain vascular disorders are involved in the pathological processes of CNS injuries and might play key roles for their recovery and prognosis. Recently, increasing evidence has shown that long non-coding RNAs (lncRNAs), which comprise a very heterogeneous group of non-protein-coding RNAs greater than 200 nucleotides, have emerged as functional mediators in the regulation of vascular homeostasis under pathophysiological conditions. Remarkably, lncRNAs can regulate gene transcription and translation, thus interfering with gene expression and signaling pathways by different mechanisms. Hence, a deeper insight into the function and regulatory mechanisms of lncRNAs following CNS injury, especially cerebrovascular-related lncRNAs, could help in establishing potential therapeutic strategies to improve or inhibit neurological disorders. In this review, we highlight recent advancements in understanding of the role of lncRNAs and their application in mediating cerebrovascular pathologies after CNS injury.

Delayed transient obstructive hydrocephalus after cerebral aneurysm rupture: A case report

RATIONALE

Obstructive hydrocephalus (OH) frequently occurs in patients with a ruptured cerebral aneurysm (CA), and it may lead to severe neurological deficits, including life-threatening brain herniation. OH generally occurs in the early stage of CA rupture, rather than in the late stage, and rarely resolves without therapy.

PATIENT CONCERNS

A 64-year-old woman with a ruptured anterior communicating artery aneurysm was treated with coil embolization. Nineteen days after her CA rupture, because of the delayed transient OH, she experienced a dramatic cycle in consciousness over 9 hours: wakefulness-drowsiness-coma-drowsiness-wakefulness.

DIAGNOSIS

The patient was diagnosed with delayed transient obstructive hydrocephalus, which is a very rare condition.

INTERVENTIONS

Mannitol was administered to reduce intracranial pressure.

OUTCOMES

The patient was discharged from the hospital 30 days after admission, with a final GCS score of 15 and without weaknesses. At follow-up 2 months after discharge, brain CT revealed non-recurrence of hydrocephalus.

LESSONS

A blood clot of any size in the ventricle is likely to lead to obstructive hydrocephalus. Prolonged bed rest for IVH patients may help to reduce the incidence of delayed OH.

A Highly Predictive MicroRNA Panel for Determining Delayed Cerebral Vasospasm Risk Following Aneurysmal Subarachnoid Hemorrhage

Approximately one-third of aneurysmal subarachnoid hemorrhage (aSAH) patients develop delayed cerebral vasospasm (DCV) 3-10 days after aneurysm rupture resulting in additional, permanent neurologic disability. Currently, no validated biomarker is available to determine the risk of DCV in aSAH patients. MicroRNAs (miRNAs) have been implicated in virtually all human diseases, including aSAH, and are found in extracellular biofluids including plasma and cerebrospinal fluid (CSF). We used a custom designed TaqMan Low Density Array miRNA panel to examine the levels of 47 selected brain and vasculature injury related miRNAs in CSF and plasma specimens collected from 31 patients with or without DCV at 3 and 7 days after aSAH, as well as from eight healthy controls. The analysis of the first 18-patient cohort revealed a striking differential expression pattern of the selected miRNAs in CSF and plasma of aSAH patients with DCV from those without DCV. Importantly, this differential expression was observed at the early time point (3 days after aSAH), before DCV event occurs. Seven miRNAs were identified as reliable DCV risk predictors along with a prediction model constructed based on an array of additional 19 miRNAs on the panel. These chosen miRNAs were then used to predict the risk of DCV in a separate, testing cohort of 15 patients. The accuracy of DCV risk prediction in the testing cohort reached 87%. The study demonstrates that our novel designed miRNA panel is an effective predictor of DCV risk and has strong applications in clinical management of aSAH patients.

Edema Resolution and Clinical Assessment in Poor-Grade Subarachnoid Hemorrhage: Useful Indicators to Predict Delayed Cerebral Infarctions?

Background: The level of consciousness and cerebral edema are among the indicators that best define the intensity of early brain injury following aneurysmal subarachnoid hemorrhage (aSAH). Although these indicators are usually altered in patients with a poor neurological status, their usefulness for selecting patients at risk of cerebral infarction (CI) is not well established. Furthermore, little is known about the evolution of these indicators during the first week of post-ictal events. Our study focused on describing the association of the longitudinal course of these predictors with CI occurrence in patients with severe aSAH. Methods: Out of 265 aSAH patients admitted consecutively to the same institution, 80 patients with initial poor neurological status (WFNS 4–5) were retrospectively identified. After excluding 25 patients with early mortality, a total of 47 patients who underwent early CT (<3 days) and late CT (<7 days) acquisitions were included in the study. Early cerebral edema and delayed cerebral edema were calculated using the SEBES score, and the level of consciousness was recorded daily during the first week using the Glasgow Coma Scale (GCS). Results: There was a significant improvement in the SEBES (Early-SEBES median (IQR) = 3 (2–4) versus Delayed-SEBES = 2 (1–3); p = 0.001) and in GCS scores (B = 0.32; 95% CI 0.15–0.49; p = 0.001) during the first week. When comparing the ROC curves of Delayed-SEBES vs Early-SEBES as predictors of CI, no significant differences were found (Early-SEBES Area Under the Curve: 0.65; Delayed-SEBES: 0.62; p = 0.17). Additionally, no differences were observed in the relationship between the improvement in the GCS across the first week and the occurrence of CI (p = 0.536). Conclusions: Edema and consciousness level improvement did not seem to be associated with the occurrence of CI in a surviving cohort of patients with severe aSAH. Our results suggest that intensive monitoring should not be reduced in patients with a poor neurological status regardless of an improvement in cerebral edema and level of consciousness during the first week after bleeding.

miR-4463 regulates aromatase expression and activity for 17β-estradiol synthesis in response to follicle-stimulating hormone

Objective

The aim of this study was to investigate microRNAs (miRNAs) related to follicle-stimulating hormone (FSH) responsiveness using miRNA microarrays and to identify their target genes to determine the molecular regulatory pathways involved in FSH signaling in KGN cells.

Methods

To change the cellular responsiveness to FSH, KGN cells were treated with FSH receptor (FSHR)-specific small interfering RNA (siRNA) followed by FSH. miRNA expression profiles were determined through miRNA microarray analysis. Potential target genes of selected miRNAs were predicted using bioinformatics tools, and their regulatory function was confirmed in KGN cells.

Results

We found that six miRNAs (miR-1261, miR-130a-3p, miR-329-3p, miR-185-5p, miR-144-5p and miR-4463) were differentially expressed after FSHR siRNA treatment in KGN cells. Through a bioinformatics analysis, we showed that these miRNAs were predicted to regulate a large number of genes, which we narrowed down to cytochrome P450 family 19 subfamily A member 1 (CYP19A1) and estrogen receptor alpha (ESR1) as the main targets for miR-4463. Functional analysis revealed that miR-4463 is a regulatory factor for aromatase expression and function in KGN cells.

Conclusion

In this study, we identified differentially expressed miRNAs related to FSH responsiveness. In particular, upregulation of miR-4463 expression by FSHR deficiency in human granulosa cells impaired 17β-estradiol synthesis by targeting CYP19A1 and ESR1. Therefore, our data might provide novel candidates for molecular biomarkers for use in research into poor responders.

Circular RNA (circRNA) CDYL Induces Myocardial Regeneration by ceRNA After Myocardial Infarction

Background

The aim of the study was to assess the effect of circRNA CDYL on myocardial angiogenesis after acute myocardial infarction (AMI).

Material/Methods

We compared changes in circRNA CDYL and myocardial angiogenesis in myocardial infarction tissue and normal heart tissue by establishing a myocardial infarction mouse model to clarify the relationship between circRNA CDYL and changes in myocardial infarction and myocardial angiogenesis. Secondly, we used the RegRNA website to predict downstream miRNA, and we performed gain-of-function and loss-of-function experiments.

Results

CircCDYL was downregulated in myocardial tissues and hypoxia myocardial cells, and overexpression and downregulation of circCDYL improved and aggravated, respectively, heart function after AMI. CircCDYL overexpression and downregulation can promote and inhibit, respectively, proliferation of cardiomyocytes in vitro. Finally, we found that circCDYL can sponge miR-4793-5p and regulate its expression, and then miR-4793-5p regulates APP expression.

Conclusions

CircCDYL can promote the proliferation of cardiomyocytes through the miR-4793-5p/APP pathway.

Correlation of MMP-9 gene polymorphisms with aneurysmal subarachnoid hemorrhage and its prognosis

Background: Aneurysmal subarachnoid hemorrhage (aSAH)-associated gene polymorphism is of great significance for the accurate diagnosis and individualized treatment of aSAH. This study aims to investigate the expression of matrix metalloproteinase-9 (MMP-9) gene in the peripheral blood of patients with aneurysmal subarachnoid hemorrhage (aSAH) and explore the correlations of MMP-9 polymorphisms with the onset and prognosis of the disease. Methods: A total of 80 aSAH patients (aSAH group) and 24 healthy (control group) people receiving physical examination were enrolled in the study. Western blotting was applied to detect the expression of MMP-9 gene in the peripheral blood in aSAH patients and healthy people. The genotyping of single nucleotide polymorphisms (rs42512, rs56212 and rs61221) in the promoter region of MMP-9 gene was analyzed by means of conformation-difference gel electrophoresis. Chi-square test was applied to examine the applicability of the distribution frequency of MMP-9 genotypes with genetic equilibrium law. The correlations of MMP-9 alleles and gene polymorphisms with the onset and prognosis of aSAH were determined. Results: The expression of MMP-9 protein in aSAH group was significantly higher than that in control group (P<0.05). The Hardy-Weinberg equilibrium analysis showed that MMP-9 gene polymorphisms were in agreement with the genetic equilibrium law. According to the results of genetic association analysis, only the polymorphism rs42512 and its alleles were significantly correlated with the onset and prognosis of aSAH (P<0.05). However, polymorphisms rs56212 and rs61221 and their alleles had no association with the onset and prognosis of aSAH (P>0.05). Conclusion: The polymorphism rs42512 in the promoter region of MMP-9 gene is related to the onset of aSAH, which provides further evidence for the diagnosis of aSAH.

MicroRNA and their target mRNAs change expression in whole blood of patients after intracerebral hemorrhage

Previous studies showed changes in mRNA levels in whole blood of rats and humans, and in miRNA in whole blood of rats following intracerebral hemorrhage (ICH). Thus, this study assessed miRNA and their putative mRNA targets in whole blood of humans following ICH. Whole transcriptome profiling identified altered miRNA and mRNA levels in ICH patients compared to matched controls. Target mRNAs of the differentially expressed miRNAs were identified, and functional analysis of the miRNA-mRNA targets was performed. Twenty-nine miRNAs (22 down, 7 up) and 250 target mRNAs (136 up, 114 down), and 7 small nucleolar RNA changed expression after ICH compared to controls (FDR < 0.05, and fold change ≥ |1.2|). These included Let7i, miR-146a-5p, miR210-5p, miR-93-5p, miR-221, miR-874, miR-17-3p, miR-378a-5p, miR-532-5p, mir-4707, miR-4450, mir-1183, Let-7d-3p, miR-3937, miR-4288, miR-4741, miR-92a-1-3p, miR-4514, mir-4658, mir-3689d-1, miR-4760-3p, and mir-3183. Pathway analysis showed regulated miRNAs/mRNAs were associated with toll-like receptor, natural killer cell, focal adhesion, TGF-β, phagosome, JAK-STAT, cytokine-cytokine receptor, chemokine, apoptosis, vascular smooth muscle, and RNA degradation signaling. Many of these pathways have been implicated in ICH. The differentially expressed miRNA and their putative mRNA targets and associated pathways may provide diagnostic biomarkers as well as point to therapeutic targets for ICH treatments in humans.

Influence of butyphthalide combined with urinary kallikrein in ACI treatment on neuro-cytokines and vascular endothelial function and its clinical effect

Objective: To study the influence of butyphthalide combined with urinary kallikrein in acute cerebral infarction (ACI) treatment on neuro-cytokines and indicators of vascular endothelial function, observe the curative effect and adverse effects, and discuss its safety and feasibility.Method: 110 ACI patients were chosen as the objects, and classified into observation group (55 cases) and control group (55 cases) according to the method of random number table. Butyphthalide injection combined with urinary kallikrein was adopted for the observation group based on conventional treatment, while cinepazide maleate injection combined with alprostadil injection was applied for the control group based on conventional treatment. The following indicators of both groups were compared before and after treatment: neurotrophic factor (NTF), nerve growth factor (NGF), neuron specific enolase (NSE); content of CXC chemotactic factor ligand 16 (CXCL16), soluble CD ligand (CD40L), Fibulin-5 and high mobility group box B1 (HMGB1); the content of indicators of vascular endothelial function including plasma endothelin -1 (ET-1) and no therapeutic effects and adverse effects were recorded.Results: NSE of both groups after treatment decreased obviously, and the content of NTF and NGF increased obviously. NSE content of observation group was lower than that of control group. NTF content and NGF content of observation group were higher than those of control group. The differences had statistical significance (p < 0.05). The levels of CXCL16, CD40L, Fibulin-5 and HMGB1 declined obviously, compared with pre-treatment, and the levels of observation groups were significantly lower than those of control grip. The differences had statistical significance (p < 0.05). ET-1 level rose significantly after treatment, and NO level declined obviously after treatment. ET-1 level of observation group was significantly higher than that of control group, and NO level of observation group was significantly lower than that of control group. The difference had statistical significance (p < 0.05). Clinical effect of observation group was significantly higher than that of control group. The difference had statistical significance (p < 0.05). The comparison difference of both groups in the occurrence rate of adverse effects had no statistical significance (p > 0.05).Conclusion: The application of butyphthalide combined with urinary kallikrein in ACI treatment can effectively inhibit secretion and release of neuro-cytokines, and improve patients' vascular endothelial function, with significant treatment effect and high safety. Therefore, it deserves to be promoted clinically.

Biospecimens and Molecular and Cellular Biomarkers in Aneurysmal Subarachnoid Hemorrhage Studies: Common Data Elements and Standard Reporting Recommendations

INTRODUCTION

Development of clinical biomarkers to guide therapy is an important unmet need in aneurysmal subarachnoid hemorrhage (SAH). A wide spectrum of plausible biomarkers has been reported for SAH, but none have been validated due to significant variabilities in study design, methodology, laboratory techniques, and outcome endpoints.

METHODS

A systematic review of SAH biomarkers was performed per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The panel's recommendations focused on harmonization of (1) target cellular and molecular biomarkers for future investigation in SAH, (2) standardization of best-practice procedures in biospecimen and biomarker studies, and (3) experimental method reporting requirements to facilitate meta-analyses and future validation of putative biomarkers.

RESULTS

No cellular or molecular biomarker has been validated for inclusion as "core" recommendation. Fifty-four studies met inclusion criteria and generated 33 supplemental and emerging biomarker targets. Core recommendations include best-practice protocols for biospecimen collection and handling as well as standardized reporting guidelines to capture the heterogeneity and variabilities in experimental methodologies and biomarker analyses platforms.

CONCLUSION

Significant variabilities in study design, methodology, laboratory techniques, and outcome endpoints exist in SAH biomarker studies and present significant barriers toward validation and translation of putative biomarkers to clinical use. Adaptation of common data elements, recommended biospecimen protocols, and reporting guidelines will reduce heterogeneity and facilitate future meta-analyses and development of validated clinical biomarkers in SAH.

Plasma and CSF miRNA dysregulations in subarachnoid hemorrhage reveal clinical courses and underlying pathways

BACKGROUND

Subarachnoid hemorrhage (SAH) is fatal and detrimental to quality of life. Clinically, options for monitoring are often limited, potentially missing subtle neurological changes especially in low-grade patients. This article reviewed miRNA dysregulation in SAH and analyzed their functional and clinical relevance.

METHODS

With adherence to PRISMA guideline, PubMed, EMBASE, GEO and ArrayExpress were searched comprehensively for relevant clinical and animal models. Datasets were analyzed and enriched by experimentally validated targets and multiple databases using R v3.4.2, Ingenuity Pathway Analysis, and miRPath v3.0.

RESULTS

Among 1926 search results, 18 studies were screened for full-text assessment. The 8 included studies revealed a marked miRNA dysregulation after SAH. 2 datasets were retrieved. In both serum and CSF, different miRNA profiles were associated with Early Brain Injury, Delayed Cerebral Infarction, vasospasm and prognosis. In CSF, a dramatic restructure of inter-miRNA correlation matrix was observed. Enrichment analysis revealed strong association (1) BBB instability, with adherens, extra-cellular matrix, actin cytoskeleton, integrin, TGF-β, Wnt/β-catenin etc; (2) autophagy, with MTORC1, HIF-1, ULK2, and FoxO etc; (3) apoptosis, with PI3K-Akt, p53, and AMPK. We analyzed common miRNAs across SAH and cerebral ischemia. They were related to neuronal differentiation, oxidation stress, apoptosis, angiogenesis, Alzheimer's disease, NMDA-induced calcium influx, excitotoxicity and NO production.

CONCLUSIONS

Clinical progression of SAH is associated with different miRNA fingerprints. They carry neuro-pathological relevance and can be a potential biomarker which compliments SAH management.

Global miRNA expression profile reveals novel molecular players in aneurysmal subarachnoid haemorrhage

The molecular mechanisms behind aneurysmal subarachnoid haemorrhage (aSAH) are still poorly understood. Expression patterns of miRNAs may help elucidate the post-transcriptional gene expression in aSAH. Here, we evaluate the global miRNAs expression profile (miRnome) of patients with aSAH to identify potential biomarkers. We collected 33 peripheral blood samples (27 patients with cerebral aneurysm, collected 7 to 10 days after the haemorrhage, when usually is the cerebral vasospasm risk peak, and six controls). Then, were performed small RNA sequencing using an Illumina Next Generation Sequencing (NGS) platform. Differential expression analysis identified eight differentially expressed miRNAs. Among them, three were identified being up-regulated, and five down-regulated. miR-486-5p was the most abundant expressed and is associated with poor neurological admission status. In silico miRNA gene target prediction showed 148 genes associated with at least two differentially expressed miRNAs. Among these, THBS1 and VEGFA, known to be related to thrombospondin and vascular endothelial growth factor. Moreover, MYC gene was found to be regulated by four miRNAs, suggesting an important role in aneurysmal subarachnoid haemorrhage. Additionally, 15 novel miRNAs were predicted being expressed only in aSAH, suggesting possible involvement in aneurysm pathogenesis. These findings may help the identification of novel biomarkers of clinical interest.

Increased concentration of serum periostin is associated with poor outcome of patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE

To explore the role of serum periostin in patients with aneurysmal subarachnoid hemorrhage (aSAH).

METHOD

We conducted a retrospective study and 124 aSAH patients treated in Shenzhen People's hospital during March 1st 2015 to December 30th 2016 were included. Baseline information, neurological status and clinical outcome were recorded. Blood samples on admission were collected and enzyme linked immunosorbent assay (ELISA) kits were used to detect the serum level of periostin. Spearman's Correlation Analysis was used to analyze the correlation between periostin and clinical severity. Receiver operating characteristic (ROC) curve was performed to investigate variables' prognostic value in patients with aSAH.

RESULTS

The average age of patients included was 57.23 years old. Preliminary analysis revealed that serum periostin was significantly correlated with clinical severity. Patients with poor outcome at 12 months had higher level of periostin than patients with good outcome. Multivariate logistic regression analysis showed elevated level of periostin was significantly associated with poor outcome and the AUC was 0.85 for periostin in predicting poor outcome of patient with aSAH.

CONCLUSION

Elevated serum periostin concentrations are significantly associated with clinical severity and poor outcome of aSAH patients, which indicate serum periostin can be used as a prognostic biomarker in patients with aSAH.

Modified high-throughput quantification of plasma microRNAs in heparinized patients with coronary artery disease using heparinase

Heparin, a widely used anticoagulant in cardiovascular diseases, is notorious for its inhibitory effect on qRT-PCR-based detection. Heparinase I could degrade heparin in RNA. qRT-PCR-based TaqMan Low Density Array (TLDA) technology is commonly used for circulating microRNAs (miRNAs) profiling analysis. However, the effect of heparin contamination on inhibition of miRNAs TLDA amplification, as well as the method for removing heparin during this process, are not yet well investigated. We obtained the plasma RNA samples from patients undergoing percutaneous coronary intervention (PCI) before and after heparinization (n = 26). We found that heparin suppressed the miRNAs amplification by ∼8 cycles in the TLDA assay, which was absolutely reversed after treating the RNA samples with heparinase I using the components from TLDA reverse transcription system. We further observed that heparin inhibited the miRNAs amplification by ∼4 cycles in the qRT-PCR assay, which was also reversed by heparinase I using the similar method. Furthermore, we demonstrated that plasma miR-92a and miR-155 were differentially expressed in the patients undergoing PCI tested by TLDA assay, which was validated by qRT-PCR. In conclusion, we present a simple method for the removal of heparin with heparinase I, and for the subsequent successful miRNAs TLDA or RT-qPCR amplification.

MicroRNA Changes in Cerebrospinal Fluid After Subarachnoid Hemorrhage

Supplemental Digital Content is available in the text.

Background and Purpose—

Delayed cerebral ischemia (DCI) accounts for a major part of the morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH). MicroRNAs (miRNAs) are pathophysiologically involved in acute cerebral ischemia. This study compared miRNA profiles in cerebrospinal fluid from neurologically healthy patients, as well as SAH patients with and without subsequent development of DCI.

Methods—

In a prospective case–control study of SAH patients treated with external ventricular drainage and neurologically healthy patients, miRNA profiles in cerebrospinal fluid were screened and validated using 2 different high-throughput real-time quantification polymerase chain reaction techniques. The occurrence of DCI was documented in patient charts and subsequently reviewed independently by 2 physicians.

Results—

MiRNA profiles from 27 SAH patients and 10 neurologically healthy patients passed quality control. In the validation, 66 miRNAs showed a relative increase in cerebrospinal fluid from SAH patients compared with neurologically healthy patients (P<0.001); 2 (miR-21 and miR-221) showed a relative increase in SAH patients with DCI compared with those without (P<0.05) in both the screening and validation.

Conclusions—

SAH is associated with marked changes in the cerebrospinal fluid miRNA profile. These changes could be associated to the development of DCI.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01791257.

Roles of miR‑4463 in H2O2‑induced oxidative stress in human umbilical vein endothelial cells

Oxidative stress is implicated in the pathophysiology of vascular diseases, including atherosclerosis, aneurysm and arteriovenous fistula. A previous study from our lab suggested that microRNA (miR)-4463 may be involved in the pathogenesis of vascular disease; however, the roles of oxidative stress in the molecular mechanisms underlying the actions of miR-4463 in vascular disease have yet to be elucidated. The aim of the present study was to investigate the role of miR-4463 in hydrogen peroxide (H₂O₂)-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). Reverse transcription-quantitative polymerase chain reaction was used to assess the expression levels of miR-4463 in HUVECs treated with various concentrations of H₂O₂. Flow cytometry was used to evaluate the percentage of apoptotic cells, and the protein expression levels of the apoptotic markers cleaved (C)-caspase3, poly (adenosine diphosphate-ribose) polymerase 1 (PARP1), B cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax) and X-linked inhibitor of apoptosis protein (XIAP) were determined using western blot analysis. The results demonstrated that the apoptotic rate of HUVECs was increased following treatment with H₂O₂ in a concentration-dependent manner, and the expression of miR-4463 was also upregulated in a dose-dependent manner. Following transfection with miR-4463 mimics, the levels of malondialdehyde and reactive oxygen species were increased in HUVECs, with a corresponding increase in the apoptotic rate. Furthermore, western blot analysis revealed that the protein expression levels of C-caspase3, PARP1 and Bax were upregulated, whereas the levels of Bcl-2 and XIAP were downregulated. In conclusion, the present findings suggested that the upregulation of miR-4463 may enhance H₂O₂-induced oxidative stress and promote apoptosis in HUVECs in vitro.

Differential expression of microRNAs contributed to the health efficacy of EGCG inin vitrosubarachnoid hemorrhage model

(1) EGCG prevented miRNA dysregulation after SAH; (2) multi-target mechanisms of EGCG might rely on its regulatory roles on miRNAs expression, such as those miRNAs targeting p38, Ca²⁺, and autophagic activation; (3) the differential expression of miRNAs might determine the therapeutic efficacy of different concentration of EGCG.