MiR-1247-3p protects rat cardiomyocytes against hypoxia/reoxygenation-induced injury via targeting BCL2L11 and caspase-2

Inhibition of circ_0073932 attenuates myocardial ischemia‒reperfusion injury via miR-493-3p/FAF1/JNK

Oxidative stress and apoptosis play crucial roles in myocardial ischemia‒reperfusion injury (MIRI). In this study, we investigated the role of circ_0073932 in MIRI as well as its molecular mechanism. A hypoxia/reoxygenation (H/R) cardiomyocyte model was established with H9C2 cardiomyocytes, and RT-qPCR was used to measure gene expression. We observed that circ_0073932 expression was abnormally increased in the H/R cardiomyocyte model and in blood samples from MIRI patients. Inhibition of circ_0073932 suppressed H/R-induced cell apoptosis, oxidative stress (ROS, LDH and MDA), and p-JNK expression. Dual luciferase reporter assays showed that circ_0073932 targeted the downregulation of miR-493-3p, and miR-493-3p targeted the downregulation of FAF1. Furthermore, si-circ_0073932, an miR-493-3p inhibitor, oe-FAF1, or si-FAF1 were transfected into H9C2 cardiomyocytes to investigate the roles of these factors in MIRI. Our results showed that compared with the H/R group, si-circ_0073932 inhibited H/R-induced cell apoptosis, oxidative stress (ROS, LDH and MDA), and p-JNK expression. These results were reversed by the miR-493-3p inhibitor or oe-FAF1. Finally, a rat model of MIRI was established, and si-circ_0073932 was administered. Inhibition of circ_0073932 reduced the area of myocardial infarction and decreased the levels of apoptosis and oxidative stress by inhibiting the JNK signaling pathway. Our study indicated that circ_0073932 mediates MIRI via miR-493-3p/FAF1/JNK in vivo and in vitro, revealing novel insights into the pathogenesis of MIRI and providing a new target for the clinical treatment of MIRI.

Circ_0001786 facilitates gefitinib resistance and malignant progression in non-small cell lung cancer via miR-34b-5p/SRSF1

BACKGROUND

Non-small cell lung cancer (NSCLC) is a widespread cancer and gefitinib is a primary therapy for NSCLC patients. Nevertheless, the underlying mechanisms for the progression of acquired drug resistance have not been clarified. The aim of this study was to investigate the role of circular RNA (circ_0001786) in gefitinib-resistant NSCLC.

METHODS

Firstly, the expression of circ_0001786, miR-34b-5p and SRSF1 were assayed using qRT-PCR. Subsequently, CCK-8 test was utilized to measure the semi-inhibitory concentration (IC50) of cellular gefitinib. Apoptosis was identified by flow cytometry. At last, dual luciferase assay was applied to prove the binding association between miR-34b-5p, circ_0001786 or SRSF1.

RESULTS

Our research disclosed that circ_0001786 was heightened in gefitinib-resistant NSCLC cells and tissues. Knockdown of circ_0001786 restrained IC50 values of gefitinib, attenuated the clonogenic ability and facilitated apoptosis in HCC827-GR and PC9-GR. In addition, circ_0001786 was a molecular sponge for miR-34b-5p. Silencing miR-34b-5p rescued the inhibitory impact of circ_0001786 knockdown on IC50 and cell cloning ability. Moreover, miR-34b-5p directly targeted SRSF1. Importantly, circ_0001786 enhanced gefitinib tolerance and malignant development in NSCLC through miR-34b-5p/SRSF1 pathway.

CONCLUSION

This research revealed a novel mechanism by which circ_0001786 enhanced NSCLC resistance to gefitinib by sponging miR-34b-5p and upregulating SRSF1. circ_0001786 was a potential target for improving the treatment of gefitinib-resistant NSCLC patients.

Identification of differentially expressed miRNAs in plasma exosomes from patients with early-onset pre-eclampsia using next generation sequencing

Pre-eclampsia (PE), a major cause of perinatal morbidity and mortality, accounts for up to 14 % mortality of maternal and 18 % of fetal or infant mortalities. However, the pathogenesis process of PE remains unclear. The aim of this study was to identify differentially expressed microRNAs (miRNAs) in the peripheral blood exosomes of early-onset PE patients versus healthy pregnant women using high-throughput sequencing, and to find candidate miRNAs as molecular markers. Methods: Peripheral blood samples were collected from five preeclamptic patients and five healthy women. Exosomal miRNAs were sequenced using the Illumina HiSeq4000 sequencing platform. The target gene prediction, biological function enrichment, and signaling pathway prediction of the miRNAs with significant differences were carried out using the Starbase database software, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. Our results showed 65 significantly differentially expressed miRNAs in the exosomes of early-onset PE patients compared to control group, with 17 up-regulated and 48 down-regulated (P < 0.05). A total of 2231 target genes were predicted for all differentially expressed miRNAs. Biological functions enriched by these target genes were mainly associated with Ras protein signal transduction, GTPase-mediated signal transduction regulation, histone modification, and β-transforming growth factor regulatory process. Key regulatory signaling pathways included TGF-β signaling pathway, PI3K-Akt signaling pathway, MAPK signaling pathway, tumor necrosis factor signaling pathway and EGFR tyrosine kinase inhibition signaling pathways. QPCR validation in 40 independent samples for 10 miRNAs, identified three miRNAs were confirmed in the second population. MIR7151 was a most significant differentially expressed miRNAs, and predicted its downstream regulatory gene, KCNQ10T1, using Starbase software. There were significant differences in miRNA expression profiles between peripheral blood exosomes of early-onset PE patients and normal pregnant women, suggesting that these miRNAs may contribute to the pathophysiology of early-onset PE by regulating various biological functions and signaling pathways.

LncRNA PEG11as aggravates cerebral ischemia/reperfusion injury after ischemic stroke through miR-342-5p/PFN1 axis

AIM

LncRNAs are highly expressed in the CNS and regulate pathophysiological processes. However, the potential role of lncRNAs inischemic stroke (IS) remains unknown. In this study, we investigated the functions and possible molecular mechanism of lncRNA paternal expressed gene 11 antisense (PEG11as) in this process.

METHODS

Middle cerebral artery occlusion/reperfusion (MCAO/R) mice model and N2a cells model from oxygen-glucose deprivation/reoxygenation (OGD/R) were used to simulate cerebral I/R in vivo and in vitro. High-throughput sequencing (RNA-Seq) was used todetect differential expression of lncRNAs in cerebral I/R. QRT-PCR was used to detect the expression of PEG11as and miR-342-5p. Bioinformatics analysis, FISH, luciferase reporter assay, RIP, Western blot, and immunofluorescence were used to detect the interaction between PEG11as, miR-342-5p and PFN1. The effect on neuronal apoptosis was analyzed using loss-of-function combined with TUNEL, Hoechst, and caspase3 activity assays.

KEY FINDINGS

254 lncRNAs were differentially expressed in MCAO1h/R6h mice. Among them, PEG11as was significantly up-regulated. PEG11as down-regulated could markedly attenuate the brain infarct volume, alleviate neurological deficit in vivo, and effectively promote neuron survival, attenuate neuronal apoptosis both in vivo and in vitro. FISH assay discovered that PEG11as was mainly located in the cytoplasm. Furthermore, we demonstrated that PEG11as was able to bind miR-342-5p to inhibit miR-342-5p activity, whereas the down-regulated of miR-342-5p resulted in profilin 1 (PFN1) overexpression and thus promoting apoptosis.

SIGNIFICANCE

This study suggests that PEG11as regulates neuronal apoptosis by miR-342-5p/PFN1 axis, which may contribute to our understanding of pathogenesis and provide a potential therapeutic option for cerebral I/R.

Unveiling caspase-2 regulation by non-coding RNAs

Non-coding RNAs (ncRNAs) are a group of RNA molecules, such as small nucleolar RNAs, circular RNAs (circRNAs), microRNAs (miRNAs) and long-noncoding RNAs (ncRNAs), that do not encode proteins. Although their biofunctions are not well-understood, many regulatory ncRNAs appear to be highly involved in regulating the transcription and translation of several genes that have essential biological roles including cell differentiation, cell death, metabolism, tumorigenesis and so on. A growing number of studies have revealed the associations between dysregulated ncRNAs and caspases involved in cell death in numerous human diseases. As one of the initiator and executor caspases, caspase-2 is the most evolutionally conserved caspase in mammals, exerting both apoptotic and non-apoptotic functions. A great deal of studies has shown the involvement of caspase-2 as a tumor suppressor in multiple oncogene-driven cancers, and yet a comprehensive understanding of its biological roles remains largely unknown. In this review, we highlight a compilation of studies focused on the interaction between caspase-2 and miRNAs/lncRNAs in the context of different diseases in order to deepen our knowledge on the regulatory biofunctions of caspase-2 and, furthermore, provide more insight into understanding the role that ncRNAs/caspase-2 axis plays in the development of human diseases.

Identification of circRNA–miRNA–mRNA Regulatory Network and Crucial Signaling Pathway Axis Involved in Tetralogy of Fallot

Tetralogy of Fallot (TOF) is one of the most common cyanotic congenital heart diseases (CHD) worldwide; however, its pathogenesis remains unclear. Recent studies have shown that circular RNAs (circRNAs) act as “sponges” for microRNAs (miRNAs) to compete for endogenous RNA (ceRNA) and play important roles in regulating gene transcription and biological processes. However, the mechanism of ceRNA in TOF remains unclear. To explore the crucial regulatory connections and pathways of TOF, we obtained the human TOF gene, miRNA, and circRNA expression profiling datasets from the Gene Expression Omnibus (GEO) database. After data pretreatment, differentially expressed mRNAs (DEmRNAs), microRNAs (DEmiRNAs), and circRNAs (DEcircRNAs) were identified between the TOF and healthy groups, and a global triple ceRNA regulatory network, including circRNAs, miRNAs, and mRNAs based on the integrated data, was constructed. A functional enrichment analysis was performed on the Metascape website to explore the biological functions of the selected genes. Then, we constructed a protein-protein interaction (PPI) network and identified seven hub genes using the cytoHubba and MCODE plug-ins in the Cytoscape software, including BCL2L11, PIK3R1, SOCS3, OSMR, STAT3, RUNX3, and IL6R. Additionally, a circRNA–miRNA–hub gene subnetwork was established, and its enrichment analysis results indicated that the extrinsic apoptotic signaling pathway, JAK-STAT signaling pathway and PI3K-Akt signaling pathway may be involved in the pathogenesis of TOF. We further identified the hsa_circ_000601/hsa-miR-148a/BCL2L11 axis as a crucial signaling pathway axis from the subnetwork. This study provides a novel regulatory network for the pathogenesis of TOF, revealing the possible molecular mechanisms and crucial regulatory pathways that may provide new strategies for candidate diagnostic biomarkers or potential therapeutic targets for TOF.

Protective Effects of MicroRNA-200b-3p Encapsulated by Mesenchymal Stem Cells-Secreted Extracellular Vesicles in Myocardial Infarction Via Regulating BCL2L11

Background Extracellular vesicles (EVs) are a popular treatment candidate for myocardial injury. This work investigated the effects of mesenchymal stem cells (MSCs)-secreted EVs-derived miR-200b-3p on cardiomyocyte apoptosis and inflammatory response after myocardial infarction (MI) through targeting BCL2L11 (Bcl-2-like protein 11) . Methods and Results EVs from MSCs were isolated and identified. EVs from MSCs with transfection of miR-200b-3p for overexpression were injected into MI mice. The effect of miR-200b-3p on cardiac function, infarction area, myocardial fibrosis, cardiomyocyte apoptosis, and inflammatory response was determined in MI mice. The targeting relationship between miR-200b-3p and BCL2L11 was verified, and the interaction between BCL2L11 and NLR family pyrin domain containing 1 (NLRP1) was also verified. MI mice were injected with an overexpressing BCL2L11 lentiviral vector to clarify whether BCL2L11 can regulate the effect of miR-200b-3p on MI mice. EVs from MSCs were successfully extracted. MSCs-EVs improved cardiac function and reduced infarction area, apoptosis of cardiomyocytes, myocardial fibrosis, and inflammation in MI mice. Upregulation of miR-200b-3p further enhanced the effects of MSCs-EVs on the myocardial injury of MI mice. BCL2L11 was targeted by miR-200b-3p and bound to NLRP1. Upregulation of BCL2L11 negated the role of miR-200b-3p-modified MSCs-EVs in MI mice. Conclusions A summary was obtained that miR-200b-3p-encapsulated MSCs-EVs protect against MI-induced apoptosis of cardiomyocytes and inflammation via suppressing BCL2L11.

Role of long noncoding RNA KCNQ1 overlapping transcript 1/microRNA-124-3p/BCL-2-like 11 axis in hydrogen peroxide (H2O2)-stimulated human lens epithelial cells

Age-related cataract (ARC) is one of the most common causes of vision loss in aging people. This research analyzed the functions and mechanism of long noncoding RNA KCNQ1 overlapping transcript 1 (KCNQ1OT1) in hydrogen peroxide (H₂O₂)-stimulated human lens epithelial cells (SRA01/04 cells) in ARC. SRA01/04 cells were stimulated with 200 µM H₂O₂ to establish oxidative damage in the ARC model. A MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and flow cytometry analysis were conducted to evaluate cell growth and apoptosis. The relevance between KCNQ1OT1 and microRNA (miR)-124-3p or miR-124-3p and BCL-2-like 11 (BCL2L11) was measured through Starbase and a dual luciferase reporter gene assay. The levels of KCNQ1OT1 and miR-124-3p were assessed via quantitative real-time polymerase chain reaction (qRT-PCR). We observed that KCNQ1OT1 was over-expressed and miR-124-3p was low-expressed in H₂O₂-stimulated SRA01/04 cells. KCNQ1OT1 interacted with miR-124-3p and negatively mediated its levels. In addition, KCNQ1OT1-siRNA reversed the effects of H₂O₂ on SRA01/04 cells, evidenced by enhanced cell viability, inhibited apoptotic cells, promoted Bcl-2 expression, and reduced Bax levels. Nevertheless, these observations were inverted after miR-124-3p inhibitor treatment. Likewise, miR-124-3p mimic had a protective effect on H₂O₂-stimulated SRA01/04 cells. Our data suggested that BCL2L11 targeted miR-124-3p directly. In summary, the data indicated that lncRNA KCNQ1OT1 down-regulation protected SRA01/04 cells from oxidative stress stimulated damage via the miR-124-3p/BCL2L11 pathway.

Circulating microRNA-208 family as early diagnostic biomarkers for acute myocardial infarction: A meta-analysis

OBJECTIVE

Many recent studies have demonstrated that serum miRNA-208 (miR-208) could be a powerful biomarker in the early diagnosis of acute myocardial infarction (AMI). However, the result of previous studies was not accurate due to the small sample sizes and controversial issues. Therefore, this study was performed to investigate the relationship between the expression levels of miR-208 and AMI.

MATERIALS AND METHODS

According to the inclusion and exclusion criteria, a preliminary literature search was performed. The study was based on articles published in PubMed, Embase, Cochrane databases before September 30, 2019. Two staff members extracted data from the included articles for meta-analysis. These data were analyzed for sensitivity, specificity, diagnostic odds ratio, and summary receiver operator curve (SROC) analyses.

RESULTS

This study included 13 pieces of literature, which contains 1703 patients with AMI and 1589 controls. The main results of our meta-analysis were as follows: The pool sensitivity and specificity of miR-208 for diagnosing AMI was 83% and 97%. The area under the SROC curve (AUC) was 93%. Mir-208 had a highly effective diagnostic capacity to distinguish AMI from chest pain patients with an AUC of 93%.

CONCLUSIONS

The results showed that circulating miR-208 was a reliable biomarker both for diagnosting ST-elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI). MiR-208 was sufficient to distinguish AMI patients with chest pain from healthy controls.

Potentially Functional microRNA-mRNA Regulatory Networks in Intestinal Ischemia-Reperfusion Injury: A Bioinformatics Analysis

Background

Intestinal ischemia-reperfusion (II/R) injury is a common clinical complication associated with high mortality, for which microRNA (miRNA) drives potentially its pathophysiological progression. MiRNAs regulate different messenger RNAs (mRNAs). However, the regulatory network between miRNAs and mRNAs in intestinal ischemia-reperfusion injury is elusive.

Methods

We analyzed the different expression of mRNAs and miRNAs in intestinal tissues from patients from three groups (arterial group (group A), venous group (group V), control group (group C)). Common differentially expressed (Co-DE) miRNAs and differentially expressed mRNAs were acquired via concerned analyses among the three groups. Co-DE mRNAs were shared parts of target mRNAs and differentially expression mRNAs. Cytoscape was employed to construct the regulatory network between miRNAs and mRNAs. Gene Ontology (GO) analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway depicted the functions and potential pathway associated with Co-DE mRNAs. Using the STRING and Cytoscape, we found critical mRNAs in the protein–protein interaction (PPI) network.

Results

The miRNA-mRNA network comprised 8 Co-DE miRNAs and 140 Co-DE mRNAs. Of note, 140 Co-DE mRNAs were targets of these 8 miRNAs, and their roles were established through the functional exploration via GO analysis and KEGG analysis. PPI network and Cytoscape revealed COL1A2, THY1, IL10, MMP2, SERPINH1, COL3A1, COL14A1, and P4HA1 as the top 8 key mRNAs.

Conclusion

This study has demonstrated a miRNA-mRNA regulatory network in intestinal ischemia-reperfusion injury, and explored the key mRNAs and their potential functions. These findings could provide new insight into prognostic markers and therapeutic targets for patients with intestinal ischemia-reperfusion injury in clinical practice.

Roles of noncoding RNAs in the initiation and progression of myocardial ischemia-reperfusion injury

The morbidity and mortality of myocardial ischemia-reperfusion injury (MIRI) have increased in modern society. Noncoding RNAs (ncRNAs), including lncRNAs, circRNAs, piRNAs and miRNAs, have been reported in a variety of studies to be involved in pathological initiation and developments of MIRI. Hence this review focuses on the current research regarding these ncRNAs in MIRI. We comprehensively introduce the important features of lncRNAs, circRNAs, piRNA and miRNAs and then summarize the published studies of ncRNAs in MIRI. A clarification of lncRNA-miRNA-mRNA, lncRNA-transcription factor-mRNA and circRNA-miRNA-mRNA axes in MIRI follows, to further elucidate the crucial roles of ncRNAs in MIRI. Bioinformatics analysis has revealed the biological correlation of mRNAs with MIRI. We provide a comprehensive perspective for the roles of these ncRNAs and their related networks in MIRI, providing a theoretical basis for preclinical and clinical studies on ncRNA-based gene therapy for MIRI treatment.

MeCP2 attenuates cardiomyocyte hypoxia/reperfusion-induced injury via regulation of the SFRP4/Wnt/β-catenin axis

Objective: Methylated CpG binding protein 2 (MeCP2) is closely associated with heart failure, but its role in I/R injury remains unclear. The purpose of this study was to explore the role and underling mechanism of MeCP2 in myocardial I/R injury.Methods: Hypoxia/reperfusion (H/R)-induced H9c2 cardiomyocytes was used to establish an in vitro I/R injury model. Oxidative stress was assessed by measuring reactive oxygen species (ROS) generation, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity. Cell viability and cell cycle arrest were evaluated by the Cell Counting Kit-8 assay and cell cycle assay, respectively. Apoptosis was determined using flow cytometry analysis.Results: The expression of MeCP2 in H9c2 cells was decreased after H/R treatment. The overexpression of MeCP2 inhibited H/R-induced oxidative stress, cell cycle arrest and apoptosis of H9c2 cells. Moreover, MeCP2 inhibited the activation of secreted frizzled related protein 4 (SFRP4)/Wnt/β-catenin axis, and SFRP4 relieved the effect of MeCP2 on oxidative stress, cell cycle arrest and apoptosis in H/R-induced H9c2 cells.Conclusions: MeCP2 attenuated H/R-induced injury in H9c2 cardiomyocytes by modulating the SFRP4/Wnt/β-catenin axis, which suggested that MeCP2 might serve as a therapeutic target of patients with AMI after reperfusion.