Circulating lncRNA ANRIL in the Serum of Patients with Ischemic Stroke

Associations between low serum levels of ANRIL and some common gene SNPs in Iranian patients with premature coronary artery disease

Coronary artery disease (CAD) is the major cause of mortality in the world. Premature development of CAD can be attributed to women under 55 and men under 45. Many genetic factors play a part in premature CAD. Among them, ANRIL, a long noncoding RNA is located at the 9p21 risk locus, and its expression seems to be correlated with CAD. In the current study, premature CAD and control blood samples, with and without Type 2 Diabetes (T2D), were genotyped for six SNPs at the 9p21 locus. Additionally, ANRIL serum expression was assessed in both groups using real-time PCR. It was performed using different primers targeting exons 1, 5-6, and 19. The χ2 test for association, along with t-tests and ANOVA, was employed for statistical analysis. In this study, we did not find any significant correlation between premature coronary artery disease and rs10757274, rs2383206, rs2383207, rs496892, rs10757278 and rs10738605. However, a lower ANRIL expression was correlated with each SNP risk genotype. Despite the correlation between lower ANRIL expression and CAD, Type 2 diabetes was associated with higher ANRIL expression. Altogether, the correlation between ANRIL expression and the genotypes of the studied SNPs indicated that genetic variants, even those in intronic regions, affect long noncoding RNA expression levels. In conclusion, we recommend combining genetic variants with expression analysis when developing screening strategies for families with premature CAD. To prevent the devastating outcomes of CAD in young adults, it is crucial to discover noninvasive genetic-based screening tests.

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.

Long Non-Coding RNAs in Venous Thromboembolism: Where Do We Stand?

Venous thromboembolism (VTE), a common condition in Western countries, is a cardiovascular disorder that arises due to haemostatic irregularities, which lead to thrombus generation inside veins. Even with successful treatment, the resulting disease spectrum of complications considerably affects the patient's quality of life, potentially leading to death. Cumulative data indicate that long non-coding RNAs (lncRNAs) may have a role in VTE pathogenesis. However, the clinical usefulness of these RNAs as biomarkers and potential therapeutic targets for VTE management is yet unclear. Thus, this article reviewed the emerging evidence on lncRNAs associated with VTE and with the activity of the coagulation system, which has a central role in disease pathogenesis. Until now, ten lncRNAs have been implicated in VTE pathogenesis, among which MALAT1 is the one with more evidence. Meanwhile, five lncRNAs have been reported to affect the expression of TFPI2, an important anticoagulant protein, but none with a described role in VTE development. More investigation in this field is needed as lncRNAs may help dissect VTE pathways, aiding in disease prediction, prevention and treatment.

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 non-coding RNAs as biomarkers and therapeutic targets for ischemic stroke

Background

The problem of ischemic stroke (IS) has become increasingly important in recent years, as it ranks first in the structure of disability and mortality, crowding out other vascular diseases. In this regard, the study of this pathology and the search for new therapeutic and diagnostic tools remains an urgent problem of modern medical science and practice. Long non-coding RNAs (lncRNAs)-based therapeutics and diagnostic tools offer a very attractive area of study. Therefore, this systematic review aims at summarizing current knowledge on promising lncRNAs as biomarkers and therapeutic targets for IS exploring original articles and literature reviews on in vivo, in vitro and ex vivo experiments.

Methods

The current systematic review was performed according to PRISMA guidelines. PubMed, MEDLINE and Google Scholar databases were comprehensively explored to perform the article search.

Results

34 eligible studies were included and analyzed: 25 focused on lncRNAs-based therapeutics and 9 on lncRNAs-based diagnosis. We found 31 different lncRNAs tested as potential therapeutic and diagnostic molecules in cells and animal model experiments. Among all founded lncRNA-based therapeutics and non-invasive diagnostic tools, nuclear enriched abundant transcript 1 (NEAT1) emerged to be the most investigated and proposed as a potential molecule for IS diagnosis and treatment.

Conclusions

Our analysis provides a snapshot of the current scenario regarding the lncRNAs as therapeutic molecules and biomarkers in IS. Different lncRNAs are differently expressed in IS, and some of them can be further evaluated as therapeutic targets and biomarkers for early diagnosis and prognosis or treatment response. However, despite many efforts, none of the selected studies go beyond preclinical studies, and their translation into clinical practice seems to be very premature.

Long Non-coding RNA ANRIL Downregulation Alleviates Neuroinflammation in an Ischemia Stroke Model via Modulation of the miR-671-5p/NF-κB Pathway

The aim of this study was to investigate the role and underlying mechanism of the long non-coding RNA ANRIL (antisense noncoding RNA in the INK4 locus, ANRIL) in ischemia stroke (IS) injury. Downregulation of ANRIL by right intracerebroventricular injected si-ANRIL in middle cerebral artery occlusion-reperfusion (MCAO/R) C57/BL6 mice and by transferring si-ANRIL in oxygen glucose deprivation/reperfusion (OGD/R) HT22 cells. The results showed that ANRIL levels increased in IS model, downregulation of ANRIL reduced infract area, neurological deficit scores and injured cells, and prolong fall latency time in MCAO/R mice, improved cell viability and reduced cell cytotoxicity in OGD/R cells. Fluorescence in Situ Hybridization detected that there were both ANRIL and miR-671-5p in neurons; miranda v3.3a and dual luciferase reporter assay demonstrated that miR-671-5p was one of direct target of ANRIL; and our previously published research demonstrated that NF-κB was one of direct target of miR-671-5p. Downregulation of ANRIL alleviated neuroinflammation and reduced p-NF-κB, NF-κB, pro-inflammatory cytokines (IL-1β, IL-6, TNF-a), and iNOS, which diminished by miR-671-5p antagomir both in in vivo and in vitro IS models. Downregulation of ANRIL alleviated disruption of blood brain barrier, and protected against tight junction (ZO-1, occludin and claudin 5) disorder in MCAO/R mice. This work clarified that downregulation of ANRIL reduced neuroinflammation by negatively regulating miR-671-5p to inhibit NF-κB in IS models, which provided a theoretical foundation for the protective effect of downregulating ANRIL for IS patients.

Circulating expression and clinical significance of LncRNA ANRIL in diabetic kidney disease

BACKGROUND

Long noncoding RNA ANRIL has been found to be involved in the pathogenesis of diabetic kidney disease (DKD) and is expected to be a new target for prevention of DKD. However, the circulating expression and clinical significance of ANRIL in DKD patients is uncertain. This study aims to explore this issue.

METHODS

The study consisted of 20 healthy controls, 22 T2DM patients (normalbuminuria) and 66 DKD patients (grouped as follows: microalbuminuria, n = 23; macroalbuminuria, n = 22 and renal dysfunction, n = 21). The expressions of ANRIL in peripheral whole blood of all participants were measured by RT-qPCR.

RESULTS

The expression of ANRIL was significantly up-regulated in DKD patients (microalbuminuria, macroalbuminuria and renal dysfunction groups) than that in healthy control group. ANRIL was also over-expressed in macroalbuminuria and renal dysfunction groups in comparison with normalbuminuria group. ANRIL expression was positively correlated with Scr, BUN, CysC, urine β2-MG and urine α1-MG; while negatively correlated with eGFR in DKD patients. In addition, ANRIL was the risk factor for DKD with OR value of 1.681. The AUC of ANRIL in identifying DKD was 0.922, and the sensitivity and specificity of DKD diagnosis were 83.3% and 90.5%, respectively.

CONCLUSION

Our results indicated that highly expressed ANRIL in peripheral blood is associated with progression of DKD. Circulating ANRIL is an independent risk factor of DKD and has a highly predictive value in identifying DKD.

LncRNA CASC15 Promotes Cerebral Ischemia/Reperfusion Injury via miR-338-3p/ETS1 Axis in Acute Ischemic Stroke

Purpose

Acute ischemic stroke (AIS) is a leading health problem caused by cerebral ischemia/reperfusion (CI/R). This study aimed to unveil the potential clinical value and mechanism of lncRNA CASC15.

Patients and Methods

The expression of CASC15, miR-338-3p was detected by quantitative real-time PCR (qRT-PCR). The correlations between CASC15 and national institutes of health stroke scale (NIHSS) scores or miR-338-3p were evaluated by Pearson correlation. A receiver operating characteristic (ROC) curve was performed to provide the diagnostic value of CASC15. Cell Counting Kit-8 (CCK-8) and flow cytometer were used to detect the condition of cell viability and apoptosis. The levels of interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) was detected by enzyme-linked immunosorbent assay (ELISA) assay.

Results

The expression of CASC15 was increased and the levels of miR-338-3p were decreased in AIS patients. A positive association between CASC15 and NIHSS score and an inverse association between CASC15 and miR-338-3p were revealed by Pearson correlation. CASC15 might discriminate AIS patients from healthy people. Silenced CASC15 exerted neuroprotective roles on cell viability, apoptosis, and inflammation via the miR-338-3p/ETS1 axis.

Conclusion

CASC15 might act as a potential diagnostic biomarker for AIS patients. CASC15/miR-338-3p/ETS1 axis played an essential role in cell viability, apoptosis, and neuroinflammation.

Thoracic and abdominal aortic aneurysms: exploring their contrast and genetic associations

Until recently thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) were correlated with atherosclerosis but following a range of cohort studies, a linkage proved unlikely. Instead, data from the Genome wide association study detected two common significantly correlated lncRNA loci: miRNA and the antisense non-coding RNA in the INK4 locus (ANRIL). lncRNAs are sometimes utilized by the body as transcription regulators and signaling molecules. This is crucial in cell transformation and embryology, including that of the mammalian heart. ANRIL, a 19 exon RNA sequence found in the chromosome 9p21 region, will be one of the main focuses of this paper. TAA and AAA have many differences due to their vessel walls but similarities in their gross anatomic structure prove a genetic correlated disease likely. ANRIL has a convincing potential to be used as an additive therapeutic tool in TAA and AAA. This is because Chr9p21 is independent of typical risk factors. However, it remains that further research and clinical studies are required before clinical translation. It is best to consider TAA and AAA separately as the underlying pathophysiology has some distinct differences. They are both commonly diagnosed late, and the hope is that genetic mutations (ANRIL) can act as a biomarker for a faster diagnosis, management and possible treatment alternative.

The Regulatory Functions of lncRNAs on Angiogenesis Following Ischemic Stroke

Ischemic stroke is one of the leading causes of global mortality and disability. It is a multi-factorial disease involving multiple factors, and gene dysregulation is considered as the major molecular mechanisms underlying disease progression. Angiogenesis can promote collateral circulation, which helps the restoration of blood supply in the ischemic area and reduces ischemic necrosis following ischemic injury. Aberrant expression of long non-coding RNAs (lncRNAs) in ischemic stroke is associated with various biological functions of endothelial cells and serves essential roles on the angiogenesis of ischemic stroke. The key roles of lncRNAs on angiogenesis suggest their potential as novel therapeutic targets for future diagnosis and treatment. This review elucidates the detailed regulatory functions of lncRNAs on angiogenesis following ischemic stroke through numerous mechanisms, such as interaction with target microRNAs, downstream signaling pathways and target molecules.

LncRNAs Stand as Potent Biomarkers and Therapeutic Targets for Stroke

Stroke is a major public health problem worldwide with a high burden of neurological disability and mortality. Long noncoding RNAs (lncRNAs) have attracted much attention in the past decades because of their newly discovered roles in pathophysiological processes in many diseases. The abundance of lncRNAs in the nervous system indicates that they may be part of a complex regulatory network governing physiology and pathology of the brain. In particular, lncRNAs have been shown to play pivotal roles in the pathogenesis of stroke. In this article, we provide a review of the multifaceted functions of lncRNAs in the pathogenesis of ischemic stroke and intracerebral hemorrhage, highlighting their promising use as stroke diagnostic biomarkers and therapeutics. To this end, we discuss the potential of stem cells in aiding lncRNA applications in stroke.

Competing endogenous RNA network analysis for screening inflammation‑related long non‑coding RNAs for acute ischemic stroke

Long non-coding RNAs (lncRNAs) represent potential biomarkers for the diagnosis and treatment of various diseases; however, the role of circulating acute ischemic stroke (AIS)-related lncRNAs remains relatively unknown. The present study aimed to screen crucial lncRNAs for AIS based on the competing endogenous RNA (ceRNA) hypothesis. The expression profile datasets for one mRNA, accession no. GSE16561, and four microRNAs (miRNAs), accession nos. GSE95204, GSE86291, GSE55937 and GSE110993, were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs), lncRNAs (DELs), and miRNAs (DEMs) were identified, and ClusterProfiler was used to interpret the function of the DEGs. Based on the protein-protein interaction (PPI) network and module analyses, hub DEGs were identified. A ceRNA network was established based on miRNA-mRNA or miRNA-lncRNA interaction pairs. In total, 2,041 DEGs and 5 DELs were identified between the AIS and controls samples in GSE16561, and 10 DEMs between at least two of the four miRNA expression profiles. A PPI network was constructed with 1,235 DEGs, among which 20 genes were suggested to be hub genes. The hub genes paxillin (PXN), FYN-proto-oncogene, Src family tyrosine kinase (FYN), ras homolog family member A (RHOA), STAT1, and growth factor receptor-bound protein 2 (GRB2), were amongst the most significantly enriched modules extracted from the PPI network. Functional analysis revealed that these hub genes were associated with inflammation-related signaling pathways. An AIS-related ceRNA network was constructed, in which 4 DELs were predicted to function as ceRNAs for 9 DEMs, to regulate the five identified hub genes; that is, minichromosome maintenance complex component 3 associated protein-antisense RNA 1 (MCM3AP-AS1)/long intergenic non-protein coding RNA 1089 (LINC01089)/hsa-miRNA (miR)-125a/FYN, inositol-tetrakisphosphate 1-kinase-antisense RNA 1 (ITPK1-AS1)/hsa-let-7i/RHOA/GRB2/STAT1, and human leukocyte antigen complex group 27 (HCG27)/hsa-miR-19a/PXN interaction axes. In conclusion, MCM3AP-AS1, LINC01089, ITPK1-AS1, and HCG27 may represent new biomarkers and underlying targets for the treatment of AIS.