MiRNA: a potential target for gene diagnosis and treatment of atherosclerotic stroke

Identification and characterization of extrachromosomal circular DNA in large-artery atherosclerotic stroke

Extrachromosomal circular DNA (eccDNA) is a new biomarker and regulator of diseases. However, the role of eccDNAs in large-artery atherosclerotic (LAA) stroke remains unclear. Through high-throughput circle-sequencing technique, the length distribution, genomic characteristic and motifs feature of plasma eccDNA from healthy controls (CON) and patients with LAA stroke were analysed. Then, the potential functions of the annotated eccDNAs were investigated using GO and KEGG pathway analyses. EccDNAs mapped to the reference genome showed SHN3 and BCL6 were LAA stroke unique transcription factors. The genes of differentially expressed eccDNAs between LAA stroke patients and CON were mainly involved in axon/dendrite/neuron projection development and maintenance of cellular structure via Wnt, Rap1 and MAPK pathways. Moreover, LAA stroke unique eccDNA genes played a role in regulation of coagulation and fibrinolysis, and there were five LAA stroke unique eccDNAs (Chr2:12724406-12724784, Chr4:1867120-186272046, Chr4:186271494-186271696, Chr7:116560296-116560685 and Chr11:57611780-5761192). Additionally, POLR2C and AURKA carried by ecDNAs (eccDNA size >100 kb) of LAA stroke patients were significantly associated with development of LAA stroke. Our data firstly revealed the characteristics of eccDNA in LAA stroke and the functions of LAA stroke unique eccDNAs and eccDNA genes, suggesting eccDNA is a novel biomarker and mechanism of LAA stroke.

The phosphokinase activity of IRE1ɑ prevents the oxidative stress injury through miR-25/Nox4 pathway after ICH

BACKGROUND

Endoplasmic reticulum (ER) stress and oxidative stress are the major pathologies encountered after intracerebral hemorrhage (ICH). Inositol-requiring enzyme-1 alpha (IRE1α) is the most evolutionarily conserved ER stress sensor, which plays a role in monitoring and responding to the accumulation of unfolded/misfolded proteins in the ER lumen. Recent studies have shown that ER stress is profoundly related to oxidative stress in physiological or pathological conditions. The purpose of this study was to investigate the role of IRE1α in oxidative stress and the potential mechanism.

METHODS

A mouse model of ICH was established by autologous blood injection. The IRE1α phosphokinase inhibitor KIRA6 was administrated intranasally at 1 h after ICH, antagomiR-25 and agomiR-25 were injected intraventricularly at 24 h before ICH. Western blot analysis, RT-qPCR, immunofluorescence staining, hematoma volume, neurobehavioral tests, dihydroethidium (DHE) staining, H2O2 content, brain water content, body weight, Hematoxylin and Eosin (HE) staining, Nissl staining, Morris Water Maze (MWM) and Elevated Plus Maze (EPM) were performed.

RESULTS

Endogenous phosphorylated IRE1α (p-IRE1α), miR-25-3p, and Nox4 were increased in the ICH model. Administration of KIRA6 downregulated miR-25-3p expression, upregulated Nox4 expression, promoted the level of oxidative stress, increased hematoma volume, exacerbated brain edema and neurological deficits, reduced body weight, aggravated spatial learning and memory deficits, and increased anxiety levels. Then antagomiR-25 further upregulated the expression of Nox4, promoted the level of oxidative stress, increased hematoma volume, exacerbated brain edema and neurological deficits, whereas agomiR-25 reversed the effects promoted by KIRA6.

CONCLUSION

The IRE1α phosphokinase activity is involved in the oxidative stress response through miR-25/Nox4 pathway in the mouse ICH brain.

DAE-CFR: detecting microRNA-disease associations using deep autoencoder and combined feature representation

BACKGROUND

MicroRNA (miRNA) has been shown to play a key role in the occurrence and progression of diseases, making uncovering miRNA-disease associations vital for disease prevention and therapy. However, traditional laboratory methods for detecting these associations are slow, strenuous, expensive, and uncertain. Although numerous advanced algorithms have emerged, it is still a challenge to develop more effective methods to explore underlying miRNA-disease associations.

RESULTS

In the study, we designed a novel approach on the basis of deep autoencoder and combined feature representation (DAE-CFR) to predict possible miRNA-disease associations. We began by creating integrated similarity matrices of miRNAs and diseases, performing a logistic function transformation, balancing positive and negative samples with k-means clustering, and constructing training samples. Then, deep autoencoder was used to extract low-dimensional feature from two kinds of feature representations for miRNAs and diseases, namely, original association information-based and similarity information-based. Next, we combined the resulting features for each miRNA-disease pair and used a logistic regression (LR) classifier to infer all unknown miRNA-disease interactions. Under five and tenfold cross-validation (CV) frameworks, DAE-CFR not only outperformed six popular algorithms and nine classifiers, but also demonstrated superior performance on an additional dataset. Furthermore, case studies on three diseases (myocardial infarction, hypertension and stroke) confirmed the validity of DAE-CFR in practice.

CONCLUSIONS

DAE-CFR achieved outstanding performance in predicting miRNA-disease associations and can provide evidence to inform biological experiments and clinical therapy.

MicroRNA-124-3p alleviates cerebral ischaemia-induced neuroaxonal damage by enhancing Nrep expression

OBJECTIVE

Ischaemic stroke has a high death rate and frequently results in long-term and severe brain damage in survivors. miRNA-124-3p (miR-124-3p) treatment has been suggested to reduce ischaemia and play a vital function in avoiding neuron death. An investigation of the role of miR-124-3p, in the ischaemia damage repair or protection in the middle cerebral artery occlusion (MCAO) model and oxygen-glucose deprivation/reperfusion (OGD/R) model, was the purpose of this research.

METHODS

The expression of miRNA and mRNA in the MCAO model was predicted using bioinformatics analysis. The OGD/R neuronal model was developed. We examined the influence of a number of compounds on the OGD/R model in vitro using gain- and loss-of-function approaches.

RESULTS

For starters, miR-124-3p and Nrep level in the MCAO model were found to be lower in the model predicted by bioinformatics than in the sham-operated group. And then in the OGD/R model, miR-124-3p treatment reduced OGD/R neuronal damage, increased neuronal survival, and reduced apoptosis in cell lines. Moreover, we further looked at the impact of miR-124-3p on downstream Rnf38 and Nrep using the OGD/R model. Western blot analysis and dual-luciferase reporter assays indicated that miR-124-3p binds and inhibits Rnf38. Finally, although Nrep expression was reduced in the OGD/R model neuronal model, it was shown that miR-124-3p administration reduced apoptosis and increased neuronal activity, particularly with regard to axon regeneration-related proteins.

CONCLUSION

Our studies have shown that miR-124-3p may reduce neuronal injury by preventing Rnf38-mediated effects on the Nrep axis.

Interfering microRNA-410 attenuates atherosclerosis via the HDAC1/KLF5/IKBα/NF-κB axis

MicroRNA (miR)-410 plays a potential role in the pathogenesis of atherosclerosis. The current study mainly focuses on the underlying mechanism of miR-410/histone deacetylase 1 (HDAC1)/KLF5/nuclear factor κB (NF-κB) inhibitor α (IKBα)/NF-κB axis in atherosclerosis. miR-410 expression was determined using quantitative real-time PCR in both mouse models of atherosclerosis and human umbilical endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (ox-LDL). The study subsequently predicted regulators associated with miR-410 through bioinformatics, and their binding relation was further verified through dual luciferase reporter gene and RNA immunoprecipitation (RIP) assays, and how HDAC1 regulated KLF5 was tested through coimmunoprecipitation (coIP). In HUVECs, miR-410 and HDAC1 mRNA expression; HDAC1, KLF5, IKBα, p65, p-p65, VCAM-1, ICAM-1, and MCP-1 protein expression; and inflammatory cytokine expressions were detected using quantitative real-time PCR, western blot, and ELISA. The present study further tested cell functions by Cell Counting Kit-8 (CCK-8), flow cytometry, and the colony-formation assay. It was revealed that miR-410 could target HDAC1, whereas HDAC1 could target transcription factor KLF5, increasing IKBα expression, thus suppressing NF-κB in atherosclerosis. Furthermore, silencing miR-410 or overexpressing HDAC1 increased cell viability and suppressed apoptosis and an inflammatory reaction in HUVECs in atherosclerosis. Blocking miR-410 promotes HDAC1 expression and increases IKBα levels through KLF5 to suppress NF-κB, thus preventing development of atherosclerosis.

Long Noncoding RNA OIP5-AS1 Promotes the Disease Progression in Nasopharyngeal Carcinoma by Targeting miR-203

Nasopharyngeal carcinoma (NPC) is a kind of malignancy generated from the nasopharyngeal epithelium. Recently, long noncoding RNA (lncRNA) has been shown to be involved in the regulation of many signaling pathways and is closely associated with carcinogenesis and tumor progression. However, the precise role of lncRNA Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) in NPC is not well understood. Here, we find that OIP5-AS1 is overexpressed in NPC patient specimens and NPC cell lines. Further investigations reveal that knockdown of OIP5-AS1 significantly inhibits the proliferation, migration, and invasion and accelerates the apoptosis of NPC cells in vitro. Consistent with these findings, NPC progression is significantly slowed in mice when OIP5-AS1 is knocked down. Interestingly, there is a functional link between OIP5-AS1 and microRNA-203 (miR-203), a tumor suppressor, in NPC cells. In conclusion, our data demonstrate that OIP5-AS1 plays an important role in the development and progression of NPC by targeting miR-203 and therefore provide a promising target for the treatment of NPC.