Identification of Novel Circulating miRNAs in Patients with Acute Ischemic Stroke

Neuroprotective Therapeutic Potential of microRNA-149-5p against Murine Ischemic Stroke

Ischemic stroke resulting from blockade of brain vessels lacks effective treatments, prompting exploration for potential therapies. Among promising candidates, microRNA-149 (miR-149) has been investigated for its role in alleviating oxidative stress, inflammation, and neurodegeneration associated with ischemic conditions. To evaluate its therapeutic effect, male Wistar rats were categorized into five groups, each consisting of 27 rats: sham, MCAO, lentiviral control, lentiviral miR-149, and miR149-5p mimic. Treatments were microinjected intracerebroventricularly (ICV) (right side), and ischemia was induced using middle cerebral artery occlusion (MCAO) procedure. Post-MCAO, neurological function, histopathological changes, blood-brain barrier (BBB) permeability, cerebral edema, and mRNA levels of Fas ligand (Faslg) and glutamate ionotropic NMDA receptor 1 (GRIN1) were assessed, alongside biochemical assays. MiR-149 administration improved neurological function, reduced brain damage, preserved BBB integrity, and attenuated cerebral edema. Upregulation of miR149-5p decreased Faslg and GRIN1 expression in ischemic brain regions. MiR-149 also reduced oxidative stress, enhanced antioxidant activity, decreased caspase-1 and - 3 activity, and modulated inflammatory factors in ischemic brain regions. Moreover, DNA fragmentation as an index of cell death decreased following miR-149 treatment. In conclusion, the study underscores miR-149 potential as a neuroprotective agent against ischemic stroke, showcasing its efficacy in modulating various mechanisms and supporting its candidacy as a promising therapeutic target for innovative strategies in stroke treatment.

MiRNAs as potential therapeutic targets and biomarkers for non-traumatic intracerebral hemorrhage

Non-traumatic intracerebral hemorrhage (ICH) is the most common type of hemorrhagic stroke, most often occurring between the ages of 45 and 60. Hypertension is most often the cause of ICH. Less often, atherosclerosis, blood diseases, inflammatory changes in cerebral vessels, intoxication, vitamin deficiencies, and other reasons cause hemorrhages. Cerebral hemorrhage can occur by diapedesis or as a result of a ruptured vessel. This very dangerous disease is difficult to treat, requires surgery and can lead to disability or death. MicroRNAs (miRNAs) are a class of non-coding RNAs (about 18-22 nucleotides) that are involved in a variety of biological processes including cell differentiation, proliferation, apoptosis, etc., through gene repression. A growing number of studies have demonstrated miRNAs deregulation in various cardiovascular diseases, including ICH. In addition, given that computed tomography (CT) and/or magnetic resonance imaging (MRI) are either not available or do not show clear signs of possible vessel rupture, accurate and reliable analysis of circulating miRNAs in biological fluids can help in early diagnosis for prevention of ICH and prognosis patient outcome after hemorrhage. In this review, we highlight the up-to-date findings on the deregulated miRNAs in ICH, and the potential use of miRNAs in clinical settings, such as therapeutic targets and non-invasive diagnostic/prognostic biomarker tools.

miRNAs as modulators of neuroinflammation and excitotoxicity: Implications for stroke therapeutics

Stroke is a widespread neurological disorder associated with physical disabilities, mortality, and economic burden. In recent decades, substantial progress has been achieved in reducing the impact of this public health problem. However, further understanding of the pathophysiology of stroke and the underlying genetic pathways is required. The pathological mechanisms of stroke comprise multifaceted molecular cascades regulated by various microRNAs (miRNAs). An increasing number of studies have highlighted the role of miRNAs, which have received much attention during the last decades as an important class of post-transcriptional regulators. It was shown that miRNAs exert their role in the etiology of stroke via mediating excitotoxicity and neuroinflammation. Additionally, miRNAs could be helpful as non-invasive or minimally invasive biomarkers and therapeutic agents. Thus, the current review focused on the interplay of these miRNAs in stroke pathology to upgrade the existing therapeutic strategies.

A case-control comparison of acute-phase peripheral blood gene expression in participants diagnosed with minor ischaemic stroke or stroke mimics

BACKGROUND

Past studies suggest that there are changes in peripheral blood cell gene expression in response to ischaemic stroke; however, the specific changes which occur during the acute phase are poorly characterised. The current study aimed to identify peripheral blood cell genes specifically associated with the early response to ischaemic stroke using whole blood samples collected from participants diagnosed with ischaemic stroke (n = 29) or stroke mimics (n = 27) following emergency presentation to hospital. Long non-coding RNA (lncRNA), mRNA and micro-RNA (miRNA) abundance was measured by RNA-seq, and the consensusDE package was used to identify genes which were differentially expressed between groups. A sensitivity analysis excluding two participants with metastatic disease was also conducted.

RESULTS

The mean time from symptom onset to blood collection was 2.6 h. Most strokes were mild (median NIH stroke scale score 2.0). Ten mRNAs (all down-regulated in samples provided by patients experiencing ischaemic stroke) and 30 miRNAs (14 over-expressed and 16 under-expressed in participants with ischaemic stroke) were significantly different between groups in the whole cohort and sensitivity analyses. No significant over-representation of gene ontology categories by the differentially expressed genes was observed. Random forest analysis suggested a panel of differentially expressed genes (ADGRG7 and miRNAs 96, 532, 6766, 6798 and 6804) as potential ischaemic stroke biomarkers, although modelling analyses demonstrated that these genes had poor diagnostic performance.

CONCLUSIONS

This study provides evidence suggesting that the early response to minor ischaemic stroke is predominantly reflected by changes in the expression of miRNAs in peripheral blood cells. Further work in independent cohorts particularly in patients with more severe stroke is needed to validate these findings and investigate their clinical relevance.

MicroRNAs as Potential Biomarkers of Post-Traumatic Epileptogenesis: A Systematic Review

Structural or post-traumatic epilepsy often develops after brain tissue damage caused by traumatic brain injury, stroke, infectious diseases of the brain, etc. Most often, between the initiating event and epilepsy, there is a period without seizures-a latent period. At this time, the process of restructuring of neural networks begins, leading to the formation of epileptiform activity, called epileptogenesis. The prediction of the development of the epileptogenic process is currently an urgent and difficult task. MicroRNAs are inexpensive and minimally invasive biomarkers of biological and pathological processes. The aim of this study is to evaluate the predictive ability of microRNAs to detect the risk of epileptogenesis. In this study, we conducted a systematic search on the MDPI, PubMed, ScienceDirect, and Web of Science platforms. We analyzed publications that studied the aberrant expression of circulating microRNAs in epilepsy, traumatic brain injury, and ischemic stroke in order to search for microRNAs-potential biomarkers for predicting epileptogenesis. Thus, 31 manuscripts examining biomarkers of epilepsy, 19 manuscripts examining biomarkers of traumatic brain injury, and 48 manuscripts examining biomarkers of ischemic stroke based on circulating miRNAs were analyzed. Three miRNAs were studied: miR-21, miR-181a, and miR-155. The findings showed that miR-21 and miR-155 are associated with cell proliferation and apoptosis, and miR-181a is associated with protein modifications. These miRNAs are not strictly specific, but they are involved in processes that may be indirectly associated with epileptogenesis. Also, these microRNAs may be of interest when they are studied in a cohort with each other and with other microRNAs. To further study the microRNA-based biomarkers of epileptogenesis, many factors must be taken into account: the time of sampling, the type of biological fluid, and other nuances. Currently, there is a need for more in-depth and prolonged studies of epileptogenesis.

Construction of a novel circRNA-miRNA-ferroptosis related mRNA network in ischemic stroke

Molecule alterations are important to explore the pathological mechanism of ischemic stroke (IS). Ferroptosis, a newly recognized type of regulated cell death, is related to IS. Identification of the interactions between circular RNA (circRNA), microRNA (miRNA) and ferroptosis related mRNA may be useful to understand the molecular mechanism of IS. The circRNA, miRNA and mRNA transcriptome data in IS, downloaded from the Gene Expression Omnibus (GEO) database, was used for differential expression analysis. Ferroptosis related mRNAs were identified from the FerrDb database, followed by construction of circRNA-miRNA-ferroptosis related mRNA network. Enrichment and protein-protein interaction analysis of mRNAs in circRNA-miRNA-mRNA network was performed, followed by expression validation by reverse transcriptase polymerase chain reaction and online dataset. A total of 694, 41 and 104 differentially expressed circRNAs, miRNAs and mRNAs were respectively identified in IS. Among which, dual specificity phosphatase 1 (DUSP1), nuclear receptor coactivator 4 (NCOA4) and solute carrier family 2 member 3 (SLC2A3) were the only three up-regulated ferroptosis related mRNAs. Moreover, DUSP1, NCOA4 and SLC2A3 were significantly up-regulated in IS after 3, 5 and 24 h of the attack. Based on these three ferroptosis related mRNAs, 4 circRNA-miRNA-ferroptosis related mRNA regulatory relationship pairs were identified in IS, including hsa_circ_0071036/hsa_circ_0039365/hsa_circ_0079347/hsa_circ_0008857-hsa-miR-122-5p-DUSP1, hsa_circ_0067717/hsa_circ_0003956/hsa_circ_0013729-hsa-miR-4446-3p-SLC2A3, hsa_circ_0059347/hsa_circ_0001414/hsa_circ_0049637-hsa-miR-885-3p-SLC2A3, and hsa_circ_0005633/hsa_circ_0004479-hsa-miR-4435-NCOA4. In addition, DUSP1 is involved in the signaling pathway of fluid shear stress and atherosclerosis. Relationship of regulatory action between circRNAs, miRNAs and ferroptosis related mRNAs may be associated with the development of IS.

LncRNA-PEAK1 promotes neuronal apoptosis after intracerebral hemorrhage by miR-466i-5p/caspase 8 axis

Background

At present, the treatment of intracerebral hemorrhage (ICH)-induced secondary brain injury (ISB) is limited, and the curative effect is not good. Long noncoding RNAs (lncRNAs) have been reported to play a role in ISB after ICH. We preliminarily monitored the induction effect of lncRNA-pseudopodium-enriched atypical kinase 1 (PEAK1) on neuronal cell apoptosis after ICH through our previous study and further experimental verification. However, the specific role and mechanism of lncRNA-PEAK1 in neuronal cell apoptosis after ICH have not been reported.

Methods

ICH cell models were established with hemin. Pro-inflammatory cytokines, cell proliferation, and apoptosis were evaluated by enzyme-linked immunosorbent assay, Cell Counting Kit-8 assay, flow cytometry, and terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. Moreover, lncRNA expression associated with apoptosis was confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The biological functions of lncRNA-PEAK1, miR-466i-5p, and caspase8 were conducted in vitro. Further, we used bioinformatics, a dual-luciferase reporter assay, and rescue experiments to understand the mechanisms of competitive endogenous RNAs.

Results

qRT-PCR revealed that lncRNA-PEAK1 was markedly upregulated in ICH cell models. LncRNA-PEAK1 knockdown decreased the interleukin-1β and tumor necrosis factor-alpha levels, promoted cell proliferation, weakened cell apoptosis, and downregulated the key molecular protein levels involved in the cell apoptosis pathway. Bioinformatics analysis and dual-luciferase reporter assay revealed that lncRNA bound to miR-466i-5p, and caspase 8 was a target of miR-466i-5p. The mechanistic analysis demonstrated that lncRNA-PEAK1/miR-466i-5p promoted neuronal cell apoptosis by activating the apoptosis pathway through caspase8 after ICH.

Conclusion

Collectively, our investigation identified that the lncRNA-PEAK1/miR-446i-5p/caspase8 axis is closely related to neuronal cell apoptosis after ICH. Additionally, lncRNA-PEAK1 may be a potential target for ICH intervention.

Circulating MicroRNA Profiling Identifies Distinct MicroRNA Signatures in Acute Ischemic Stroke and Transient Ischemic Attack Patients

Transient ischemic attack (TIA) refers to a momentary neurologic deficit caused by focal cerebral, spinal or retinal ischemic insult. TIA is associated with a high risk of impending acute ischemic stroke (AIS), a neurologic dysfunction characterized by focal cerebral, spinal or retinal infarction. Understanding the differences in molecular pathways in AIS and TIA has merit for deciphering the underlying cause for neuronal deficits with long-term effects and high risks of morbidity and mortality. In this study, we performed comprehensive investigations into the circulating microRNA (miRNA) profiles of AIS (n = 191) and TIA (n = 61) patients. We performed RNA-Seq on serum samples collected within 24 hrs of clinical diagnosis and randomly divided the study populations into discovery and validation cohorts. We identified a panel of 11 differentially regulated miRNAs at FDR < 0.05. Hsa-miR-548c-5p, -20a-5p, -18a-5p, -484, -652-3p, -486-3p, -24-3p, -181a-5p and -222-3p were upregulated, while hsa-miR-500a-3p and -206 were downregulated in AIS patients compared to TIA patients. We also probed the previously validated gene targets of our identified miRNA panel to highlight the molecular pathways affected in AIS. Moreover, we developed a multivariate classifier with potential utilization as a discriminative biomarker for AIS and TIA patients. The underlying molecular pathways in AIS compared to TIA may be explored further in functional studies for therapeutic targeting in clinical translation.

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.

Identification of distinct circulating microRNAs in acute ischemic stroke patients with type 2 diabetes mellitus

Stroke is the second leading cause of global mortality and continued efforts aim to identify predictive, diagnostic, or prognostic biomarkers to reduce the disease burden. Circulating microRNAs (miRNAs) have emerged as potential biomarkers in stroke. We performed comprehensive circulating miRNA profiling of ischemic stroke patients with or without type 2 diabetes mellitus (T2DM), an important risk factor associated with worse clinical outcomes in stroke. Serum samples were collected within 24 h of acute stroke diagnosis and circulating miRNAs profiled using RNA-Seq were compared between stroke patients with T2DM (SWDM; n = 92) and those without T2DM (SWoDM; n = 98). Our analysis workflow involved random allocation of study cohorts into discovery (n = 96) and validation (n = 94) datasets. Five miRNAs were found to be differentially regulated in SWDM compared to SWoDM patients. Hsa-miR-361-3p and -664a-5p were downregulated, whereas miR-423-3p, -140-5p, and -17-3p were upregulated. We also explored the gene targets of these miRNAs and investigated the downstream pathways associated with them to decipher the potential pathways impacted in stroke with diabetes as comorbidity. Overall, our novel findings provide important insights into the differentially regulated miRNAs, their associated pathways and potential utilization for clinical benefits in ischemic stroke patients with diabetes.

Efficacy of Rosuvastatin Combined with rt-PA Intravenous Thrombolytic Therapy for Elderly Acute Ischemic Stroke Patients

Background

Acute ischemic stroke (AIS) is a fatal and disabling disease. Given the unsatisfactory results by current treatment strategies, optimizing the treatment of AIS is still an urgent problem to be solved.

Objective

To determine the therapeutic efficacy of rosuvastatin (ROS) combined with thrombolytic therapy using recombinant tissue plasminogen activator (rt-PA) on senile AIS patients and analyze its effects on serum inflammatory responses and neurological function.

Methods

A retrospective study was conducted on 150 senile AIS patients who visited the Longmen County People's Hospital between January 2019 and June 2021. Of them, 100 cases treated by ROS combined with rt-PA intravenous thrombolytic therapy (ivTT) were set as the observation group and the rest 50 cases receiving rt-PA alone were included in the control group. Intergroup comparisons were conducted with respect to the following parameters: neurological function (National Institutes of Health Stroke Scale, NIHSS; Scandinavian Stroke Scale, SSS), serum neuron-specific enolase (NSE) and high-sensitivity C-reactive protein (hs-CRP), therapeutic efficacy, incidence of adverse reactions, and patient satisfaction.

Results

The observation group had lower NIHSS and SSS scores and serum NSE and hs-CRP than the control group. In addition, the observation group was found with a higher overall response rate, higher patient satisfaction, and fewer adverse reactions.

Conclusion

ROS combined with rt-PA ivTT can better enhance the therapeutic efficacy of elderly patients with AIS, improve their neurological function, and reduce serum inflammatory responses.

Circulating miRNA-195-5p and -451a in Patients with Acute Hemorrhagic Stroke in Emergency Department

(1) Background: In our previous study, acute ischemic stroke (AIS) patients showed increased levels of circulating miRNAs (-195-5p and -451a) involved in vascular endothelial growth factor A (VEGF-A) regulation. Here, we evaluated, for the first time, both circulating miRNAs in acute intracerebral hemorrhagic (ICH) patients. (2) Methods: Circulating miRNAs and serum VEGF-A were assessed by real-time PCR and ELISA in 20 acute ICH, 21 AIS patients, and 21 controls. These were evaluated at hospital admission (T0) and after 96 h (T96) from admission. (3) Results: At T0, circulating miRNAs were five-times up-regulated in AIS patients, tending to decrease at T96. By contrast, in the acute ICH group, circulating miRNAs were significantly increased at both T0 and T96. Moreover, a significant decrease was observed in serum VEGF-A levels at T0 in AIS patients, tending to increase at T96. Conversely, in acute ICH patients, the levels of VEGF-A were significantly decreased at both T0 and T96. (4) Conclusions: The absence of a reduction in circulating miRNAs (195-5p and -451a), reported in acute ICH subjects after 96 h from hospital admission, together with the absence of increment of serum VEGF-A, may represent useful biomarkers indicating the severe brain damage status that characterizes acute ICH patients.