LncRNA TNK2-AS1 regulated ox-LDL-stimulated HASMC proliferation and migration via modulating VEGFA and FGF1 expression by sponging miR-150-5p

MiR-497-5p regulates ox-LDL-induced dysfunction in vascular endothelial cells by targeting VEGFA/p38/MAPK pathway in atherosclerosis

Background

The impairment of endothelial cells triggered by oxidized low-density lipoprotein (ox-LDL) stands as a critical event in the advancement of atherosclerosis (AS). MiR-497-5p has been recognized as a potential predictor for AS, but its precise involvement in ox-LDL-induced endothelial cell dysfunction remains to be elucidated.

Methods

An in vitro AS cell model was established by exposing human umbilical vein endothelial cells (HUVECs) to 100 μg/mL ox-LDL for 24 h. The assessment of endothelial cell function included evaluating cell viability, caspase-3 activity, inflammatory factors, and oxidative markers. Molecular mechanisms were elucidated through quantitative real-time PCR, Western blot analysis, and luciferase reporter assays.

Results

Our investigation revealed that exposure to ox-LDL led to an upregulation in miR-497-5p and p-p38 levels, while downregulating the expression of vascular endothelial growth factor A (VEGFA) and phosphorylated (p)-endothelial nitric oxide synthase (p-eNOS) in HUVECs. Ox-LDL exposure resulted in decreased cell viability and angiogenic capacity, coupled with increased apoptosis, inflammation, and oxidative stress in HUVECs, partially mediated by the upregulation of miR-497-5p. We confirmed VEGFA as a direct target of miR-497-5p. Interfering with VEGFA expression significantly reversed the effects mediated by miR-497-5p silencing in HUVECs exposed to ox-LDL.

Conclusions

In summary, our findings demonstrate that miR-497-5p exacerbates ox-LDL-induced dysfunction in HUVECs through the activation of the p38/MAPK pathway, mediated by the targeting of VEGFA.

Novel treatment from a botanical formulation Si-Miao-Yong-an decoction inhibits vasa vasorum angiogenesis and stabilizes atherosclerosis plaques via the Wnt1/β-catenin signalling pathway

CONTEXT

Si-Miao-Yong-An (SMYA) has been widely used for the clinical treatment of atherosclerosis (AS). Yet, its complete mechanism of action is not fully understood.

OBJECTIVE

To investigate the mechanism by which SMYA stabilizes AS plaques from the perspective of inhibiting vasa vasorum (VV) angiogenesis.

MATERIALS AND METHODS

We used male ApoE-/- mice to establish an AS model. The mice were divided into model, SMYA (11.7 mg/kg/d), and simvastatin (SVTT) (2.6 mg/kg/d) groups. Mice were given SMYA or SVTT by daily gavage for 8 weeks. HE staining, immunofluorescence double-labelling staining, and immunohistochemical staining were used to observe the pathological changes in the plaques. Finally, the protein and mRNA expression levels of the Wnt1/β-catenin signalling pathway were detected by Western blot and qRT-PCR, respectively.

RESULTS

SMYA significantly attenuated cholesterol crystallization, and lipid accumulation in AS plaques, resulting in smaller plaque size (0.25 mm2 vs. 0.46 mm2), and lowering ratio of plaque to lumen area (20.04% vs. 38.33%) and VV density (50.64/mm2 vs. 98.02/mm2). Meanwhile, SMYA suppressed both the positive area percentage of Wnt1 (2.53 vs. 3.56), β-catenin (3.33 vs. 5.65) and Cyclin D1 (2.10 vs. 3.27) proteins in the aortic root plaques, and mRNA expression of Wnt1 (1.38 vs. 2.09), β-catenin (2.05 vs. 3.25) and Cyclin D1 (1.39 vs. 2.57).

DISCUSSION AND CONCLUSIONS

SMYA has a protective effect against AS, which may be related to its anti-VV angiogenesis in plaques, suggesting that SMYA has the potential as a novel botanical formulation in the treatment of AS.

Long non-coding RNAs: The growth controller of vascular smooth muscle cells in cardiovascular diseases

The active proliferation and migration of vascular smooth muscle cells supports the healing of vessel damage while their abnormal aggression or destitution contribute to the aberrant intima-medial structure and function in various cardiovascular diseases, so the understanding of the proliferation disorders of vascular smooth muscle cell and the related mechanism is the basis of effective intervention and control for cardiovascular diseases. Recently, long non-coding RNAs have stood out as upstream switchers for multiple proliferative signaling pathways and molecules, and many of them have been shown to conduce to the dysregulated proliferation and apoptosis of vascular smooth muscle cells under various pathogenic stimuli. This article discusses the long non-coding RNAs disclosed and linked to atherosclerosis, pulmonary hypertension, and aneurysms, and focuses upon their modulation of vascular smooth muscle cell population affecting three deadly cardiovascular diseases.

ELK1-Induced upregulation of long non-coding TNK2-AS1 promotes the progression of acute myeloid leukemia by EZH2-mediated epigenetic silencing of CELF2

Acute myeloid leukemia (AML) is the second most common hematological malignancy after lymphoma in the world. Long non-coding RNAs (LncRNAs) have been suggested as key regulators of cancer development and progression in AML. As a member of lncRNA family, the biological role and mechanisms of tyrosine kinase non receptor 2 antisense RNA 1 (TNK2-AS1) in AML is still unclear. The expression of TNK2-AS1 was measured with RT-qPCR in AML cell lines. The changes of the proliferation, apoptosis, and differentiation in TNK2-AS1 shRNA-transfected HL-60 and THP-1 cells were detected with CCK-8, EdU, flow cytometry, Western blot, and NBT assays. Molecular control of TNK2-AS1 on CUGBP Elav-like family member 2 (CELF2) and ETS domain-containing protein-1 (ELK1) on TNK2-AS1 was assessed by chromatin immunoprecipitation (ChIP), RT-qPCR, Western blot, and RNA immunoprecipitation (RIP) assays. TNK2-AS1 expression was upregulated in AML cell lines and negatively correlated with survival patients. Knockdown of TNK2-AS1 markedly reduced AML cell proliferation and promoted apoptosis and differentiation. Likewise, TNK2-AS1 knockdown significantly suppressed tumor growth in vivo. Mechanistically, the upregulation of TNK2-AS1 was activated by transcription factor ELK1. We also uncovered that TNK2-AS1 exerted tumor-promoting effect through silencing CELF2 via binding with EZH2, thus activating PI3K/Akt pathway in AML cells. Elevated expression of TNK2-AS1 was induced by ELK1 and facilitated AML progression by suppressing CELF2 expression via EZH2-mediated epigenetic silencing, suggesting TNK2-AS1 may be a promising therapeutic target and prognostic marker for AML patients.

Antigen-Presenting Cell-Like Neutrophils Foster T Cell Response in Hyperlipidemic Patients and Atherosclerotic Mice

Neutrophils constitute abundant cellular components in atherosclerotic plaques. Most of the current studies are focused on the roles of granular proteins released by neutrophils in atherosclerosis. Here, we revealed a unique subset of neutrophils which exhibit the characteristics of antigen-presenting cell (APC) (which were called APC-like neutrophils afterwards) in atherosclerosis. The roles of APC-like neutrophils and relevant mechanisms were investigated in hyperlipidemic patients and atherosclerotic mice. Higher percentages of neutrophils and APC-like neutrophils were found in peripheral blood of hyperlipidemic patients than that of healthy donors. Meanwhile, we also identified higher infiltration of neutrophils and APC-like neutrophils in atherosclerotic mice. Ox-LDL induced Phorbol-12-myristate-13-acetate (PMA)-activated neutrophils to acquire the APC-like phenotype. Importantly, upon over-expression of APC-like markers, neutrophils acquired APC functions to promote the proliferation and interferon-γ production of CD3⁺ T cells via HLA-DR/CD80/CD86. In accordance with what found in vitro, positive correlation between neutrophils and CD3⁺ T cells was observed in hyperlipidemic patients. In conclusion, our work identifies a proinflammatory neutrophil subset in both hyperlipidemic patients and atherosclerotic mice. This unique phenotype of neutrophils could activate the adaptive immune response to promote atherosclerosis progression. Thus, this neutrophil subset may be a new target for immunotherapy of atherosclerosis.

Circular RNA circ_0002984 Promotes Cell Proliferation and Migration by Regulating miR-181b-5p/Vascular Endothelial Growth Factor Axis and PI3K-AKT Signaling Pathway in Oxidized Low-Density Lipoprotein-Treated Vascular Smooth Muscle Cells

ABSTRACT

RNAs (circRNAs) play critical roles in many diseases, including atherosclerosis (AS). However, the role and underlying mechanism of circ_0002984 in AS remain unclear. Vascular smooth muscle cells (VSMCs) treated with oxidized low-density lipoprotein (ox-LDL) were used as a AS cell model. Quantitative real-time polymerase chain reaction was conducted to detect the expression of circ_0002984, miR-181b-5p and vascular endothelial growth factor A (VEGFA). Cell proliferation was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide assay and 5-ethynyl-2'-deoxyuridine assays. Cell migration was assessed using wound healing assay and transwell assay. All protein levels were analyzed by western blot assay. The interaction between miR-181b-5p and circ_0002984 or VEGFA was confirmed by dual-luciferase reporter, RNA Immunoprecipitation, and RNA pull-down assays. Circ_0002984 and VEGFA were overexpressed, and miR-181b-5p was downregulated in serum of AS patients and ox-LDL-stimulated VSMCs. Circ_0002984 silencing inhibited ox-LDL-induced proliferation and migration in VSMCs. MiR-181b-5p was a target of circ_0002984, and miR-181b-5p inhibition counteracted the suppressing effects of circ_0002984 downregulation on proliferation and migration in ox-LDL-stimulated VSMCs. Additionally, VEGFA was a downstream target of miR-181b-5p and VEGFA upregulation abolished the suppressive influence of miR-181b-5p on proliferation and migration in ox-LDL-exposed VSMCs. Furthermore, circ_0002984 depletion blocked phosphatidylinositol 3 kinase-AKT signaling pathway by regulating miR-181b-5p and VEGFA. Circ_0002984 downregulation suppressed cell proliferation and migration by regulating miR-181b-5p/VEGFA axis and phosphatidylinositol 3 kinase-AKT pathway in ox-LDL-stimulated VEGFA, providing a new mechanism for AS pathogenesis.

Deciphering a TB-related DNA methylation biomarker and constructing a TB diagnostic classifier

We systemically identified tuberculosis (TB)-related DNA methylation biomarkers and further constructed classifiers for TB diagnosis. TB-related DNA methylation datasets were searched through October 3, 2020. Limma and DMRcate were employed to identify differentially methylated probes (DMPs) and regions (DMRs). Machine learning methods were used to construct classifiers. The performance of the classifiers was evaluated in discovery datasets and a prospective independent cohort. Eighty-nine DMPs and 24 DMRs were identified based on 67 TB patients and 45 healthy controls from 4 datasets. Nine and three DMRs were selected by elastic net regression and logistic regression, respectively. Among the selected DMRs, two regions (chr3: 195635643-195636243 and chr6: 29691631-29692475) were differentially methylated in the independent cohort (p = 4.19 × 10^-5 and 0.024, respectively). Among the ten classifiers, the 3-DMR logistic regression classifier exhibited the strongest performance. The sensitivity, specificity, and area under the curve were, respectively, 79.1%, 84.4%, and 0.888 in the discovery datasets and 64.5%, 90.3%, and 0.838 in the independent cohort. The differential diagnostic ability of this classifier was also assessed. Collectively, these data showed that DNA methylation might be a promising TB diagnostic biomarker. The 3-DMR logistic regression classifier is a potential clinical tool for TB diagnosis, and further validation is needed.

MicroRNA miR-34a-5p inhibition restrains oxidative stress injury of macrophages by targeting MDM4

OBJECTIVE

Atherosclerosis is a chronic cardiovascular disease associated with oxidative stress damage, which is caused by excessive oxidation of low-density lipoprotein (ox-LDL). The role of microRNA miR-34a-5p on oxidative stress in ox-LDL-treated macrophages was investigated in this study.

METHODS

Flow cytometry was prepared for assessing THP1-derived macrophage apoptosis. The protein and expression levels of miR-34a-5p and MDM4 were examined by Western blot and RT-qPCR, respectively. We also measured the levels of total cholesterol (TC) and triglyceride to determine the lipid accumulation. Subsequently, the activities of superoxide dismutase, malondialdehyde, and reactive oxygen species revealed the level of oxidative stress injury after miR-34a-5p and MDM4 knockdown.

RESULTS

After ox-LDL treatment, cell apoptosis of macrophages increased in a dose-dependent and time-dependent manner. With the increase of ox-LDL treatment and the prolongation of treatment time, the expression level of miR-34a-5p was upregulated. Next, interfering with miR-34a-5p inhibited lipid accumulation and oxidative stress injury in ox-LDL-stimulated macrophages. MDM4 was a target gene of miR-34a-5p and was upregulated in ox-LDL-stimulated macrophages. With the increase of ox-LDL treatment and the prolongation of treatment time, the expression level of MDM4 was downregulated. Importantly, MDM4 knockdown partially counteracted the inhibitory effect of miR-34a-5p on oxidative stress injury.

CONCLUSION

MicroRNA miR-34a-5p knockdown suppressed oxidative stress injury via MDM4 in ox-LDL-treated macrophages.

Construction and Analysis of the lncRNA-miRNA-mRNA Network Based on Competing Endogenous RNA in Atrial Fibrillation

Background

Accumulated studies have revealed that long non-coding RNAs (lncRNAs) play critical roles in human diseases by acting as competing endogenous RNAs (ceRNAs). However, functional roles and regulatory mechanisms of lncRNA-mediated ceRNA in atrial fibrillation (AF) remain unknown. In the present study, we aimed to construct the lncRNA-miRNA-mRNA network based on ceRNA theory in AF by using bioinformatic analyses of public datasets.

Methods

Microarray data sets of GSE115574 and GSE79768 from the Gene Expression Omnibus database were downloaded. Twenty-one AF right atrial appendage (RAA) samples and 22 sinus rhythm (SR) subjects RAA samples were selected for subsequent analyses. After merging all microarray data and adjusting for batch effect, differentially expressed genes were identified. Gene Ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out. A ceRNA network was constructed.

Result

A total of 8 lncRNAs and 43 mRNAs were significantly differentially expressed with fold change >1.5 (p < 0.05) in RAA samples of AF patients when compared with SR. GO and KEGG pathway analysis showed that cardiac muscle contraction pathway were involved in AF development. The ceRNA was predicted by co-expressing LOC101928304/ LRRC2 from the constructional network analysis, which was competitively combined with miR-490-3p. The expression of LOC101928304 and LRRC were up-regulated in myocardial tissue of patients with AF, while miR-490-3p was down-regulated.

Conclusion

We constructed the LOC101928304/miR-490-3p/LRRC2 network based on ceRNA theory in AF in the bioinformatic analyses of public datasets. The ceRNA network found from this study may help improve our understanding of lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of AF.

Long non-coding RNA TNK2 AS1/microRNA-125a-5p axis promotes tumor growth and modulated phosphatidylinositol 3 kinase/AKT pathway

BACKGROUND AND AIM

Long non-coding RNA (lncRNA) TNK2 AS1 is a noncoding RNA with the capability of affecting microRNAs (miRNAs) levels and gene expression. The study was designed to investigate the mechanism of TNK2 AS1 in gastric cancer.

METHODS

The loss and gain of function of TNK2 AS1 were investigated by analyzing the malignant behavior of AGS cells including the abilities of migration, invasion, and epithelial-mesenchymal transition (EMT) process via wound healing and transwell assay, as well as western blot. The targeting relationship of LncRNA TNK2 AS1 was analyzed through searching bioinformatics database, luciferase reporter assay, and RNA immunoprecipitation (RIP) assay. Tumor-bearing experiment in nude mice was performed to further confirm the regulatory role of TNK2 AS1 in vivo. Immunofluorescence assay for Ki67 expression was carried out in tumor tissues of mice model.

RESULTS

The results showed that TNK2 AS1 overexpression promoted the malignant behaviors of AGS cells, which could be weakened by miR-125a-5p mimic addition. In addition, Jumonji, At-rich interaction domain (JARID2), and phosphatidylinositol 3 kinase (PI3K)/AKT pathway were regulated by TNK2-AS1/miR-125a-5p axis. In vivo, TNK2 AS1/miR-125a-5p axis promoted tumor growth and led to increases in green fluorescence intensity and vimentin expression and a decrease in E-cadherin level, which could be mediated by JARID2 and PI3K/AKT pathway.

CONCLUSION

Therefore, a conclusion was drawn that TNK2-AS1/miR-125a-5p promoted the progression of gastric cancer.

Transcriptome sequencing analysis for the identification of stable lncRNAs associated with bovine Staphylococcus aureus mastitis

Background

Staphylococcus aureus (S. aureus) mastitis is one of the most difficult diseases to treat in lactating dairy cows worldwide. S. aureus with different lineages leads to different host immune responses. Long non-coding RNAs (lncRNAs) are reported to be widely involved in the progress of inflammation. However, no research has identified stable lncRNAs among different S. aureus strain infections. In addition, folic acid (FA) can effectively reduce inflammation, and whether the inflammatory response caused by S. aureus can be reduced by FA remains to be explored.

Methods

lncRNA transcripts were identified from Holstein mammary gland tissues infected with different concentrations of S. aureus (in vivo) and mammary alveolar cells (Mac-T cells, in vitro) challenged with different S. aureus strains. Differentially expressed (DE) lncRNAs were evaluated, and stable DE lncRNAs were identified in vivo and in vitro. On the basis of the gene sequence conservation and function conservation across species, key lncRNAs with the function of potentially immune regulation were retained for further analysis. The function of FA on inflammation induced by S. aureus challenge was also investigated. Then, the association analysis between these keys lncRNA transcripts and hematological parameters (HPs) was carried out. Lastly, the knockdown and overexpression of the important lncRNA were performed to validate the gene function on the regulation of cell immune response.

Results

Linear regression analysis showed a significant correlation between the expression levels of lncRNA shared by mammary tissue and Mac-T cells (P < 0.001, R² = 0.3517). lncRNAs PRANCR and TNK2–AS1 could be regarded as stable markers associated with bovine S. aureus mastitis. Several HPs could be influenced by SNPs around lncRNAs PRANCR and TNK2–AS1. The results of gene function validation showed PRANCR regulates the mRNA expression of SELPLG and ITGB2 within the S. aureus infection pathway and the Mac-T cells apoptosis. In addition, FA regulated the expression change of DE lncRNA involved in toxin metabolism and inflammation to fight against S. aureus infection.

Conclusions

The remarkable association between SNPs around these two lncRNAs and partial HP indicates the potentially important role of PRANCR and TNK2–AS1 in immune regulation. Stable DE lncRNAs PRANCR and TNK2–AS1 can be regarded as potential targets for the prevention of bovine S. aureus mastitis. FA supplementation can reduce the negative effect of S. aureus challenge by regulating the expression of lncRNAs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-021-00639-2.

Roles and functions of antisense lncRNA in vascular aging

Vascular aging is a major cause of morbidity and mortality in the elderly population. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), forming the intima and media layers of the vessel wall respectively, are closely associated with the process of vascular aging and vascular aging-related diseases. Numerous studies have revealed the pathophysiologic mechanism through which lncRNA contributes to vascular aging, hence more attention is now paid to the role played by antisense long non-coding RNA (AS-lncRNA) in the pathogenesis of vascular aging. Nonetheless, only a small number of studies focus on the specific mechanism through which AS-lncRNA mediates vascular aging. In this review, we summarize the roles and functions of AS-lncRNA with regards to the development of vascular aging and vascular aging-related disease. We also aim to deepen our understanding of this process and provide alternative therapeutic modalities for vascular aging-related diseases.

miR-150-5p affects AS plaque with ASMC proliferation and migration by STAT1

We explore miR-150-5p in atherosclerosis (AS). The AS model was constructed using Apo E^-/- mice with an injection of the miR-150-5p mimic or an inhibitor. Pathological characteristics were assessed using Oil red O staining and Masson staining. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot were used to analyze the expressions of microRNA-150-5p (miR-150-5p), STAT1, α-SMA (α-smooth muscle actin) and proliferating cell nuclear antigen (PCNA). Targetscan and dual-luciferase reporter assay were used to analyze the interaction between miR-150-5p and STAT1. The viability, migration, cell cycle and α-SMA and PCNA expressions in oxidized low-density lipoprotein (ox-LDL)-stimulated primary human aortic smooth muscle cells (ASMCs) were assessed using molecular experiments. miR-150-5p was reduced in both AS mice and ox-LDL-stimulated human aortic smooth muscle cells but STAT1 had the opposite effect. The miR-150-5p inhibitor alleviated the increase of lipid plaque and reduced collagen accumulation in the aortas during AS. Upregulation of α-SMA and PCNA was reversed by miR-150-5p upregulation. STAT1 was targeted by miR-150-5p, and overexpressed miR-150-5p weakened the ox-LDL-induced increase of viability and migration abilities and blocked cell cycle in ASMCs, but overexpressed STAT1 blocked the effect of the miR-150-5p mimic. This paper demonstrates that miR-150-5p has potential as a therapeutic target in AS, with plaque stabilization by regulating ASMC proliferation and migration via STAT1.

LncRNA MALAT1 Promotes Tumor Angiogenesis by Regulating MicroRNA-150-5p/VEGFA Signaling in Osteosarcoma: In-Vitro and In-Vivo Analyses

The present study aims to analyze the expression of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in human osteosarcoma (OS) cells and to investigate its role in OS-induced angiogenesis. MALAT1 expression in OS cells was significantly higher than in normal osteoblasts. The functional analysis indicated that MALAT1 appears to enhance OS-induced angiogenesis, in vitro and in vivo analyses, endothelial cell proliferation and migration, chick embryo angiogenesis assay, and zebrafish xenograft model. Mechanistically, silencing MALAT1 downregulated vascular endothelial growth factor A (VEGFA) expression and upregulated miR-150-5p expression in OS cells, and MALAT1-mediated angiogenic induction by VEGFA in OS microenvironment. Moreover, MALAT1 directly targeted miR-150-5p and miR-150-5p directly target VEGFA in OS. Overexpression of miR-150-5p downregulates VEGFA expression in OS. More notably, we showed that MALAT1 induced angiogenesis in OS microenvironment by upregulating the expression of VEGFA via targeting miR-150-5p. Overall, our findings suggest that MALAT1 promotes angiogenesis by regulating the miR-150-5p/VEGFA signaling in OS microenvironment. The findings of the molecular mechanisms of MALAT1 in tumor angiogenesis offer a new viewpoint on OS treatment.

Circ_0122396 Protects Human Lens Epithelial Cells from Hydrogen Peroxide-induced Injury by Binding to miR-15a-5p to Stimulate FGF1 Expression

BACKGROUND

Circular_0122396 (circ_0122396) has been reported to be downregulated in age-related cataract (ARC); however, the underlying mechanism remains unknown. The study aimed to reveal the role of circ_0122396 in ARC progression and underneath mechanism.

METHODS

Hydrogen peroxide (H₂O₂) was employed to induce lens epithelial cells (SRA01/04) injury. The RNA expression of circ_0122396, microRNA-15a-5p (miR-15a-5p) and fibroblast growth factor 1 (FGF1) was detected by quantitative real-time polymerase chain reaction. Protein expression was checked by western blot. Cell viability, proliferation and apoptosis were investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, 5-Ethynyl-29-deoxyuridine and flow cytometry analysis, respectively. Oxidative stress was evaluated by superoxide dismutase and catalase activity assay kits and lipid peroxidation malondialdehyde assay kit. Online databases and mechanism assays were used to predict and identify the relationship between miR-15a-5p and circ_0122396 or FGF1.

RESULTS

Circ_0122396 and FGF1 expression were significantly downregulated, but miR-15a-5p expression was upregulated in ARC tissues or/and H₂O₂-treated SRA01/04 cells in comparison with control groups. H₂O₂ treatment repressed cell proliferation and induced cell apoptosis and oxidative stress, which was attenuated after circ_0122396 overexpression. MiR-15a-5p, a target mRNA of circ_0122396, was found to participate in H₂O₂-triggered cell damage by interacting with circ_0122396. Additionally, FGF1 silencing attenuated miR-15a-5p inhibitors-mediated action. Importantly, circ_0122396 regulated FGF1 expression by interaction with miR-15a-5p in H₂O₂-treated SRA01/04 cells.

CONCLUSION

Circ_0122396 ameliorated H₂O₂-triggered cell injury by inducing FGF1 through sponging miR-15a-5p, providing a potential target for ARC therapy.

Integrative Analyses of Genes Associated With Right Ventricular Cardiomyopathy Induced by Tricuspid Regurgitation

Tricuspid regurgitation (TR) induces right ventricular cardiomyopathy, a common heart disease, and eventually leads to severe heart failure and serious clinical complications. Accumulating evidence shows that long non-coding RNAs (lncRNAs) are involved in the pathological process of a variety of cardiovascular diseases. However, the regulatory mechanisms and functional roles of RNA interactions in TR-induced right ventricular cardiomyopathy are still unclear. Accordingly, we performed integrative analyses of genes associated with right ventricular cardiomyopathy induced by TR to study the roles of lncRNAs in the pathogenesis of this disease. In this study, we used high-throughput sequencing data of tissue samples from nine clinical cases of right ventricular myocardial cardiomyopathy induced by TR and nine controls with normal right ventricular myocardium from the Genotype-Tissue Expression database. We identified differentially expressed lncRNAs and constructed a protein-protein interaction and lncRNA-messenger RNA (mRNA) co-expression network. Furthermore, we determined hub lncRNA-mRNA modules related to right ventricular myocardial disease induced by TR and constructed a competitive endogenous RNA network for TR-induced right ventricular myocardial disease by integrating the interaction of lncRNA-miRNA-mRNA. In addition, we analyzed the immune infiltration using integrated data and the correlation of each immune-related gene with key genes of the integrated expression matrix. The present study identified 648 differentially expressed mRNAs, 201 differentially expressed miRNAs, and 163 differentially expressed lncRNAs. Protein-protein interaction network analysis confirmed that ADRA1A, AVPR1B, OPN4, IL-1B, IL-1A, CXCL4, ADCY2, CXCL12, GNB4, CCL20, CXCL8, and CXCL1 were hub genes. CTD-2314B22.3, hsa-miR-653-5p, and KIF17ceRNA; SRGAP3-AS2, hsa-miR-539-5p, and SHANK1; CERS6-AS1, hsa-miR-497-5p, and OPN4; INTS6-AS1, hsa-miR-4262, and NEURL1B; TTN-AS1, hsa-miR-376b-3p, and TRPM5; and DLX6-AS1, hsa-miR-346, and BIRC7 axes were obtained by constructing the ceRNA networks. Through the immune infiltration analysis, we found that the proportion of CD4 and CD8 T cells was about 20%, and the proportion of fibroblasts and endothelial cells was high. Our findings provide some insights into the mechanisms of RNA interaction in TR-induced right ventricular cardiomyopathy and suggest that lncRNAs are a potential therapeutic target for treating right ventricular myocardial disease induced by TR.

A circular RNA, circUSP36, accelerates endothelial cell dysfunction in atherosclerosis by adsorbing miR-637 to enhance WNT4 expression

Atherosclerosis is a fatal disorder that is fundamental to various cardiovascular diseases and severely threatens people’s health worldwide. Several studies have demonstrated the role of circular RNAs (circRNAs) in the pathogenesis of atherosclerosis. circUSP36 acts as a key modulator in the progression of atherosclerosis, but the molecular mechanism underlying this role is as yet unclear. This study aimed to elucidate the mechanism by which circUSP36 exerts its function in an in vitro cell model of endothelial cell dysfunction, which is one of pathological features of atherosclerosis. The circRNA traits of circUSP36 were confirmed, and we observed high expression of circUSP36 in endothelial cells exposed to oxidized low-density lipoprotein (ox-LDL). Functional assays revealed that overexpression of circUSP36 suppressed proliferation and migration of ox-LDL-treated endothelial cells. In terms of its mechanism, circUSP36 adsorbed miR-637 by acting as an miRNA sponge. Moreover, enhanced expression of miR-637 abated the impact of circUSP36 on ox-LDL-treated endothelial cell dysregulation. Subsequently, the targeting relationship between miR-637 and WNT4 was predicted using bioinformatics tools and was confirmed via luciferase reporter and RNA pull-down assays. Notably, depletion of WNT4 rescued circUSP36-mediated inhibition of endothelial cell proliferation and migration. In conclusion, circUSP36 regulated WNT4 to aggravate endothelial cell injury caused by ox-LDL by competitively binding to miR-637; this finding indicates circUSP36 to be a promising biomarker for the diagnosis and therapy of atherosclerosis.

The lncRNA PAHRF functions as a competing endogenous RNA to regulate MST1 expression by sponging miR-23a-3p in pulmonary arterial hypertension

BACKGROUND

Emerging evidence has shown that long non-coding RNA (lncRNA) plays important roles in the development of pulmonary arterial hypertension (PAH). However, some new lncRNAs in patients with PAH are still lacking research. Herein, we examined the expression and role of lncRNA (pulmonary arterial hypertension related factor, PAHRF) in PAH.

METHODS

LncRNA PAHRF expression and localization were analyzed by realtime PCR and fluorescence in situ hybridization. Proliferation and apoptosis were detected by MTT, CCK-8, EDU staining, JC-1 assay, flow cytometry and western blotting. Luciferase activity assay was used to identify PAHRF/ miR-23a-3p/serine/threonine kinase 4 (STK4/MST1) interaction.

RESULTS

LncRNA PAHRF was down-regulated in both the PAs of PAH patients and hypoxic human pulmonary artery smooth muscle cells (PASMCs). The overexpression of PAHRF inhibited the proliferation and promoted the apoptosis of PASMCs. Similarly, we also found PAHRF overexpression decreased the proliferation under hypoxia condition. Knockdown of PAHRF exerted the opposite effects. Luciferase activity assay proved molecular binding between PAHRF and hsa-miR-23a-3p. Moreover, MST1 was confirmed to be the putative target gene and regulated by PAHRF/miR-23a-3p. In addition, we explored the molecular mechanism regulating the expression of miR-23a-3p, and found that lncRNA PAHRF acted as an endogenous sponge for miR-23a-3p, and silencing lncRNA PAHRF could up-regulate the expression of miR-23a-3p. On the contrary, PAHRF-overexpressing plasmid inhibited the expression of miR-23a-3p in hypoxia.

CONCLUSIONS

Our present study reveals a novel PAH regulating model that is composed of PAHRF, miR-23a-3p, and MST1. The aim of this study is probably going to provide a new explanation and give a further understanding of the occurrence of vascular remodeling in PAH from the perspective competing endogenous RNA hypothesis.

Circular RNA circLMF1 regulates PDGF-BB-induced proliferation and migration of human aortic smooth muscle cells by regulating the miR-125a-3p/VEGFA or FGF1 axis

Atherosclerosis is a major cause of cardiovascular disease, in which vascular smooth muscle cells (VSMCs) proliferation and migration play a vital role. Circular RNAs (circRNAs) have been reported to be correlated with the VSMCs function. Therefore, this study is designed to explore the role and mechanism of circRNA lipase maturation factor 1 (circLMF1) in Human aortic VSMCs (HASMCs). The microarray was used for detecting the expression of circLMF1 in proliferative and quiescent HASMCs. Levels of circLMF1, microRNA-125a-3p (miR-125a-3p), vascular endothelial growth factor A (VEGFA), and fibroblast growth factor 1 (FGF1) were determined by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, cell cycle progression, and migration were assessed by Cell Counting Kit-8 (CCK-8), flow cytometry, wound healing, and transwell assays, respectively. Western blot assay determined proliferating cell nuclear antigen (PCNA), Cyclin D1, matrix metalloproteinase (MMP2), osteopontin (OPN), VEGFA, and FGF1 protein levels. The possible interactions between miR-125a-3p and circLMF1, and miR-125a-3p and VEGFA or FGF1 were predicted by circbank or targetscan, and then verified by a dual-luciferase reporter, RNA Immunoprecipitation (RIP), RNA pull-down assays. CircLMF1, VEGFA, and FGF1 were increased, and miR-125a-3p was decreased in platelet-derived growth factor-BB (PDGF-BB)-inducted HASMCs. Functionally, circLMF1 knockdown hindered cell viability, cell cycle progression, and migration in PDGF-BB-treated HASMCs. Mechanically, circLMF1 could regulate VEGFA or FGF1 expression through sponging miR-125a-3p. Our findings revealed that circLMF1 deficiency could inhibit cell viability, cell cycle progression, and migration of PDGF-BB stimulated atherosclerosis model partly through the miR-125a-3p/VEGFA or FGF1 axis, suggesting that targeting circLMF1 can be a feasible therapeutic strategy for atherosclerosis.

lncRNA expression profiles and associated ceRNA network analyses in epicardial adipose tissue of patients with coronary artery disease

Epicardial adipose tissue (EAT) contributes to the pathophysiological process of coronary artery disease (CAD). The expression profiles of long non-coding RNAs (lncRNA) in EAT of patients with CAD have not been well characterized. We conducted high-throughput RNA sequencing to analyze the expression profiles of lncRNA in EAT of patients with CAD compared to patients without CAD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were executed to investigate the principal functions of the significantly dysregulated mRNAs. We confirmed a dysregulated intergenic lncRNA (lincRNA) (LINC00968) by real-time quantitative PCR (RT-qPCR). Subsequently, we constructed a ceRNA network associated with LINC00968, which included 49 mRNAs. Compared with the control group, lncRNAs and genes of EAT in CAD were characterized as metabolic active and pro-inflammatory profiles. The sequencing analysis detected 2539 known and 1719 novel lncRNAs. Then, we depicted both lncRNA and gene signatures of EAT in CAD, featuring dysregulation of genes involved in metabolism, nuclear receptor transcriptional activity, antigen presentation, chemokine signaling, and inflammation. Finally, we identified a ceRNA network as candidate modulator in EAT and its potential role in CAD. We showed the expression profiles of specific EAT lncRNA and mRNA in CAD, and a selected non-coding associated ceRNA regulatory network, which taken together, may contribute to a better understanding of CAD mechanism and provide potential therapeutic targets.Trial registration Chinese Clinical Trial Registry, No. ChiCTR1900024782.

TNK2-AS1 upregulated by YY1 boosts the course of osteosarcoma through targeting miR-4319/WDR1

Mounting research papers have suggested that long non-coding RNAs (lncRNAs) elicit important functions in the progression of osteosarcoma (OS). This study focused on the role of TNK2-AS1 in OS. TNK2-AS1 was powerfully expressed in OS tissues and cell lines. In addition, TNK2-AS1 downregulation inhibited proliferative, migratory, and invasive capacities while promoting apoptosis in OS cells. miR-4319 was removed by TNK2-AS1 and therefore TNK2-AS1 elevated WDR1 expression in OS cells. miR-4319 had an inhibitory influence on OS progression, while WDR1 was a contributor to OS progression. Rescue assays certified that TNK2-AS1 promoted malignant phenotypes in vitro and the growth in vivo of OS cells by upregulating WDR1. In depth, we found that YY1 accelerated the transcription of TNK2-AS1 in OS cells, and that its role in OS also depended on TNK2-AS1-regulated WDR1. In conclusion, TNK2-AS1 was positively modulated by YY1 and aggravated the development of OS by 'sponging' miR-4319 to elevate WDR1. The findings highlighted that TNK2-AS1 might be a promising target for the treatment of OS.

miR-188-3p Inhibits Vascular Smooth Muscle Cell Proliferation and Migration by Targeting Fibroblast Growth Factor 1 (FGF1)

Background

As one of the crucial causes leading to cardiovascular disease, atherosclerosis (AS) develops in association with the dysfunction of vascular smooth muscle cells (VSMCs). However, the associated mechanism of the proliferation and migration in VSMCs requires further elucidation.

Material/Methods

Human VSMCs and ApoE-knockout (ApoE^−/−) mice were used to establish AS cell and animal models, respectively. Expression levels of miR-188-3p and fibroblast growth factor 1 (FGF1) mRNA were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Western blot was used to assess FGF1 protein expression. The proliferation, migration, and apoptosis of the cells were determined using MTT, BrdU, and Transwell assays, as well as flow cytometry analysis. The interaction between miR-188-3p and FGF1 was validated using dual-luciferase reporter gene assay, qRT-PCR, and Western blot analysis.

Results

MiR-188-3p was found to be significantly decreased in the serum of AS patients and ApoE^−/− mice as well as VSMCs of ApoE^−/− mice and human VSMCs treated with oxidized low-density lipoprotein. MiR-188-3p repressed the proliferation and migration of VSMCs but promoted apoptosis of VSMCs. The binding site between miR-188-3p and 3′ untranslated region (3′-UTR) of FGF1 was identified, and FGF1 was verified as a target gene of miR-188-3p. Restoration of FGF1 reversed the effects of miR-188-3p on VSMCs.

Conclusions

MiR-188-3p suppresses the proliferation and migration of VSMCs and induces their apoptosis through targeting FGF1.

Long Non-coding RNA IRAIN Inhibits VEGFA Expression via Enhancing Its DNA Methylation Leading to Tumor Suppression in Renal Carcinoma

Aims: Long non-coding RNA IRAIN (lncRNA IRAIN) plays a critical role in numerous malignancies. However, the function of lncRNA IRAIN in renal carcinoma (RC) remains enigmatic. The purpose of this study is to characterize the effects of lncRNA IRAIN on RC progression.

Methods: The expression pattern of lncRNA IRAIN and the vascular endothelial growth factor A (VEGFA) in RC tissues and cells was characterized by RT-qPCR and Western blot analysis. The roles of lncRNA IRAIN and VEGFA in the progression of RC were studied by gain- or loss-of-function experiments. Bioinformatics data analysis was used to predict CpG islands in the VEGFA promoter region. MSP was applied to detect the level of DNA methylation in RC cells. The interaction between lncRNA IRAIN and VEGFA was identified by RNA immunoprecipitation and RNA-protein pull down assays. Recruitment of DNA methyltransferases (Dnmt) to the VEGFA promoter region was achieved by chromatin immunoprecipitation. The subcellular localization of lncRNA IRAIN was detected by fractionation of nuclear and cytoplasmic RNA. Cell viability was investigated by CCK-8 assay, cell migration was tested by transwell migration assay, and apoptosis was analyzed by flow cytometry. The expression of epithelial–mesenchymal transition-related and apoptotic factors was evaluated by Western blot analysis. Finally, the effect of the lncRNA IRAIN/VEGFA axis was confirmed in an in vivo tumor xenograft model.

Results: LncRNA IRAIN was poorly expressed in RC tissues and cells with a primary localization in the nucleus, while VEGFA was highly expressed. Overexpression of lncRNA IRAIN or knockdown of VEGFA inhibited cell proliferation and migration and induced the apoptosis of RC cells. Bioinformatics analysis indicated the presence of CpG islands in the VEGFA promoter region. Lack of methylation at specific sites in the VEGFA promoter region was detected through MSP assay. We found that lncRNA IRAIN was able to inhibit VEGFA expression through recruitment of Dnmt1, Dnmt3a, and Dnmt3b to the VEGFA promoter region. LncRNA IRAIN was also able to suppress RC tumor growth via repression of VEGFA in an in vivo mouse xenograft model.

Conclusion: Our data shows that by downregulating VEGFA expression in RC, the lncRNA IRAIN has tumor-suppressive potential.

Ox-LDL Causes Endothelial Cell Injury Through ASK1/NLRP3-Mediated Inflammasome Activation via Endoplasmic Reticulum Stress

Objective

This study was to investigate the mechanism of inflammatory pathology modification induced by ox-LDL in endothelial cells.

Methodology

In this study, we firstly investigated the efflux of cholesterol of endothelial cells under the treatment of ox-LDL, and cell proliferation, ROS production, cell apoptosis was measured. Further, proteins of ASK1, NLRP3 inflammasomes and endoplasmic reticulum stress response were detected. Afterwards, ASK1 inhibitor (GS-4997) or endoplasmic reticulum stress (ERS) inhibitor (4-PBA) was used to measure the performance of endothelial cells.

Results

In this study, endothelial cells were treated with ox-LDLs alone or in combination with a GS-4997 or 4-PBA. Results showed that ox-LDLs attenuated the efflux of cholesterol from endothelial cells in a dose-dependent manner. Ox-LDLs inhibited the proliferation of endothelial cells, and induced their apoptosis and production of reactive oxygen species (ROS). Additionally, ox-LDLs upregulated the levels of phosphorylated ASK1, ERS-related proteins (chop, p-PERK, GRP78, and p-IRE-1), and inflammation-associated proteins (NLRP3, IL-1β, and caspase 1) in endothelial cells. Moreover, we proved that GS-4997 could partly reverse ox-LDL-mediated cell proliferation, apoptosis, ROS production, and inflammation in endothelial cells, and increase cholesterol efflux. We also found that 4-PBA could attenuate the effects of ox-LDLs on endothelial cell cholesterol efflux, proliferation, apoptosis, ROS production, and inflammation.

Conclusion

Our results suggest that cholesterol efflux from endothelial cells is reduced by ox-LDLs, and these reductions in cholesterol efflux are accompanied by increased NLRP3 inflammasome signaling, ASK1 and higher levels of endoplasmic reticulum stress. Our results suggest this axis as potential targets for treating atherosclerosis.

LncRNA TNK2-AS1 regulated ox-LDL-stimulated HASMC proliferation and migration via modulating VEGFA and FGF1 expression by sponging miR-150-5p

Long non‐coding RNAs (lncRNAs) have been indicated for the regulatory roles in cardiovascular diseases. This study determined the expression of lncRNA TNK2 antisense RNA 1 (TNK2‐AS1) in oxidized low‐density lipoprotein (ox‐LDL)‐stimulated human aortic smooth muscle cells (HASMCs) and examined the mechanistic role of TNK2‐AS1 in the proliferation and migration of HASMCs. Our results demonstrated that ox‐LDL promoted HASMC proliferation and migration, and the enhanced proliferation and migration in ox‐LDL‐treated HASMCs were accompanied by the up‐regulation of TNK2‐AS1. In vitro functional studies showed that TNK2‐AS1 knockdown suppressed cell proliferation and migration of ox‐LDL‐stimulated HASMCs, while TNK2‐AS1 overexpression enhanced HASMC proliferation and migration. Additionally, TNK2‐AS1 inversely regulated miR‐150‐5p expression via acting as a competing endogenous RNA (ceRNA), and the enhanced effects of TNK2‐AS1 overexpression on HASMC proliferation and migration were attenuated by miR‐150‐5p overexpression. Moreover, miR‐150‐5p could target the 3’ untranslated regions of vascular endothelial growth factor A (VEGFA) and fibroblast growth factor 1 (FGF1) to regulate FGF1 and VEGFA expression in HASMCs, and the inhibitory effects of miR‐150‐5p overexpression in ox‐LDL‐stimulated HASMCs were attenuated by enforced expression of VEGFA and FGF1. Enforced expression of VEGFA and FGF1 also partially restored the suppressed cell proliferation and migration induced by TNK2‐AS1 knockdown in ox‐LDL‐stimulated HASMCs, while the enhanced effects of TNK2‐AS1 overexpression on HASMC proliferation and migration were attenuated by the knockdown of VEGFA and FGF1. Collectively, our findings showed that TNK2‐AS1 exerted its action in ox‐LDL‐stimulated HASMCs via regulating VEGFA and FGF1 expression by acting as a ceRNA for miR‐150‐5p.