Reduced microRNA-503 expression augments lung fibroblast VEGF production in chronic obstructive pulmonary disease

Non-Coding RNAs in Airway Diseases: A Brief Overview of Recent Data

Inflammation of the human lung is mediated in response to different stimuli (e.g., physical, radioactive, infective, pro-allergenic, or toxic) such as cigarette smoke and environmental pollutants. These stimuli often promote an increase in different inflammatory activities in the airways, manifesting themselves as chronic diseases (e.g., allergic airway diseases, asthma chronic bronchitis/chronic obstructive pulmonary disease, or even lung cancer). Non-coding RNA (ncRNAs) are single-stranded RNA molecules of few nucleotides that regulate the gene expression involved in many cellular processes. ncRNA are molecules typically involved in the reduction of translation and stability of the genes of mRNAs s. They regulate many biological aspects such as cellular growth, proliferation, differentiation, regulation of cell cycle, aging, apoptosis, metabolism, and neuronal patterning, and influence a wide range of biologic processes essential for the maintenance of cellular homeostasis. The relevance of ncRNAs in the pathogenetic mechanisms of respiratory diseases has been widely established and in the last decade many papers were published. However, once their importance is established in pathogenetic mechanisms, it becomes important to further deepen the research in this direction. In this review we describe several of most recent knowledge concerning ncRNA (overall miRNAs) expression and activities in the lung.

The Causes and Consequences of miR-503 Dysregulation and Its Impact on Cardiovascular Disease and Cancer

microRNAs (miRs) are short, non-coding RNAs that regulate gene expression by mRNA degradation or translational repression. Accumulated studies have demonstrated that miRs participate in various biological processes including cell differentiation, proliferation, apoptosis, metabolism and development, and the dysregulation of miRs expression are involved in different human diseases, such as neurological, cardiovascular disease and cancer. microRNA-503 (miR-503), one member of miR-16 family, has been studied widely in cardiovascular disease and cancer. In this review, we summarize and discuss the studies of miR-503 in vitro and in vivo, and how miR-503 regulates gene expression from different aspects of pathological processes of diseases, including carcinogenesis, angiogenesis, tissue fibrosis and oxidative stress; We will also discuss the mechanisms of dysregulation of miR-503, and whether miR-503 could be applied as a diagnostic marker or therapeutic target in cardiovascular disease or cancer.

Silencing of long noncoding RNA H19 alleviates pulmonary injury, inflammation, and fibrosis of acute respiratory distress syndrome through regulating the microRNA-423-5p/FOXA1 axis

PURPOSE

This study aimed to explore the regulatory effects and mechanisms of long noncoding RNA H19 (H19) on pulmonary injury, inflammation, and fibrosis of acute respiratory distress syndrome (ARDS).

MATERIALS AND METHODS

A rat model of ARDS was established by intratracheal instillation of 2 mg/kg lipopolysaccharide (LPS). qRT-PCR was performed to detect the expression of H19, miR-423-5p, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, monocyte chemoattractant protein (MCP)-1, and vascular endothelial growth factor (VEGF). Histology score was assessed by hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of proinflammatory cytokines and the content of VEGF in bronchoalveolar lavage fluid (BALF). The lung fibrosis was evaluated using western blot and Masson's trichrome staining. Dual-luciferase reporter gene assay was used for confirming the relationship between miR-423-5p and H19/FOXA1 in alveolar macrophage cells (MH-S) and alveolar epithelial cells (MLE-12). The regulatory effects of H19/miR-423-5p/FOXA1 axis on the inflammation and fibrosis were further analyzed in LPS-induced MH-S cells.

RESULTS

The expression of H19 and FOXA1 was significantly up-regulated, while the expression of miR-423-5p was down-regulated in LPS-induced ARDS rats. Silencing of H19 decreased the mRNA expression of TNF-α, IL-1β, IL-6, MCP-1, and VEGF, the contents of TNF-α, IL-1β, IL-6, and VEGF in BALF, and histology score in LPS-induced ARDS rats. H19 knockdown also reduced the fibrosis scores and the protein expression of vimentin and α-SMA, and elevated the protein expression of E-cadherin in LPS-induced ARDS rats. Furthermore, silencing of miR-423-5p and overexpression of FOXA1 reversed the inhibitory effects of si-H19 on the inflammation and fibrosis of LPS-induced MH-S cells.

CONCLUSIONS

Silencing of H19 relieved the pulmonary injury, inflammation and fibrosis of LPS-induced ARDS in rats. Silencing of H19 also alleviated the inflammation and fibrosis of LPS-induced MH-S cells through regulating the miR-423-5p/FOXA1 axis.

MicroRNAs as Potential Regulators of Immune Response Networks in Asthma and Chronic Obstructive Pulmonary Disease

Chronic respiratory diseases (CRDs) are an important factor of morbidity and mortality, accounting for approximately 6% of total deaths worldwide. The main CRDs are asthma and chronic obstructive pulmonary disease (COPD). These complex diseases have different triggers including allergens, pollutants, tobacco smoke, and other risk factors. It is important to highlight that although CRDs are incurable, various forms of treatment improve shortness of breath and quality of life. The search for tools that can ensure accurate diagnosis and treatment is crucial. MicroRNAs (miRNAs) are small non-coding RNAs and have been described as promising diagnostic and therapeutic biomarkers for CRDs. They are implicated in multiple processes of asthma and COPD, regulating pathways associated with inflammation, thereby showing that miRNAs are critical regulators of the immune response. Indeed, miRNAs have been found to be deregulated in several biofluids (sputum, bronchoalveolar lavage, and serum) and in both structural lung and immune cells of patients in comparison to healthy subjects, showing their potential role as biomarkers. Also, miRNAs play a part in the development or termination of histopathological changes and comorbidities, revealing the complexity of miRNA regulation and opening up new treatment possibilities. Finally, miRNAs have been proposed as prognostic tools in response to both conventional and biologic treatments for asthma or COPD, and miRNA-based treatment has emerged as a potential approach for clinical intervention in these respiratory diseases; however, this field is still in development. The present review applies a systems biology approach to the understanding of miRNA regulatory networks in asthma and COPD, summarizing their roles in pathophysiology, diagnosis, and treatment.

MicroRNAs in chronic airway diseases: Clinical correlation and translational applications

MicroRNAs (miRNAs) are short single-stranded RNAs that have pivotal roles in disease pathophysiology through transcriptional and translational modulation of important genes. It has been implicated in the development of many diseases, such as stroke, cardiovascular conditions, cancers and inflammatory airway diseases. There is recent evidence that miRNAs play important roles in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD), and could help to distinguish between T2-low (non-eosinophilic, steroid-insensitive) versus T2-high (eosinophilic, steroid-sensitive) disease endotypes. As these are the two most prevalent chronic respiratory diseases globally, with rising disease burden, miRNA research might lead to the development of new diagnostic and therapeutic targets. Research involving miRNAs in airway disease is challenging because: (i) asthma and COPD are heterogeneous inflammatory airway diseases; there are overlapping but distinct inter- and intra-disease differences in the immunological pathophysiology, (ii) there exists more than 2000 known miRNAs and a single miRNA can regulate multiple targets, (iii) differential effects of miRNAs could be present in different cellular subtypes and tissues, and (iv) dysregulated miRNA expression might be a direct consequence of an indirect effect of airway disease onset or progression. As miRNAs are actively secreted in fluids and remain relatively stable, they have the potential for biomarker development and therapeutic targets. In this review, we summarize the preclinical data on potential miRNA biomarkers that mediate different pathophysiological mechanisms in airway disease. We discuss the framework for biomarker development using miRNA and highlight the need for careful patient characterization and endotyping in the screening and validation cohorts, profiling both airway and blood samples to determine the biological fluids of choice in different disease states or severity, and adopting an untargeted approach. Collaboration between the various stakeholders - pharmaceutical companies, laboratory professionals and clinician-scientists is crucial to reduce the difficulties and cost required to bring miRNA research into the translational stage for airway diseases.

Epigenetic Modifications and Therapy in Chronic Obstructive Pulmonary Disease (COPD): An Update Review

Chronic obstructive pulmonary disease (COPD) that is one of the most prevalent chronic adult diseases and the third leading cause of fatality until 2020. Elastase/anti-elastase hypothesis, chronic inflammation, apoptosis, oxidant-antioxidant balance and infective repair cause pathogenesis of COPD are among the factors at play. Epigenetic changes are post-translational modifications in histone proteins and DNA such as methylation and acetylation as well as dysregulation of miRNAs expression. In this update review, we have examined recent studies on the upregulation or downregulation of methylation in different genes associated with COPD. Dysregulation of HDAC activity which is caused by some factors and miRNAs plays a key role in the suppression and reduction of COPD development. Also, some therapeutic approaches are proposed against COPD by targeting HDAC2 and miRNAs, which have therapeutic effects.

CYP1B1, VEGFA, BCL2, and CDKN1A Affect the Development of Chronic Obstructive Pulmonary Disease

Purpose

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease characterized by poor airflow. The purpose of this study was to explore the mechanisms involved in the development of COPD.

Patients and Methods

The mRNA expression profile GSE100281, consisting of 79 COPD and 16 healthy samples, was acquired from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) between COPD samples and healthy samples were analyzed using the limma package. Functional enrichment analysis for the DEGs was carried out using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) tool. Furthermore, DEG-compound pairs were predicted using the Comparative Toxicogenomics Database. The KEGG metabolite IDs corresponding to the compounds were also obtained through the MetaboAnalyst pipeline. Based on the diffusion algorithm, the metabolite network was constructed. Finally, the expression levels of key genes were determined using quantitative PCR (qPCR).

Results

There were 594 DEGs identified between the COPD and healthy samples, including 242 upregulated and 352 downregulated genes. A total of 696 DEG-compound pairs, such as BCL2-C00469 (ethanol) and BCL2-C00389 (quercetin) pairs, were predicted. CYP1B1, VEGFA, BCL2, and CDKN1A were included in the top 10 DEG-compound pairs. Additionally, 57 metabolites were obtained. In particular, hsa04750 (inflammatory mediator regulation of TRP channels)-C00469 (ethanol) and hsa04152 (AMPK signaling pathway)-C00389 (quercetin) pairs were found in the metabolite network. The results of qPCR showed that the expression of CYP1B1, VEGFA, BCL2, and CDKN1A was consistent with that predicted using bioinformatic analysis.

Conclusion

CYP1B1, VEGFA, BCL2, and CDKN1A may play important functions in the development and progression of COPD.

miR-503 Inhibits Proliferation, Migration, And Angiogenesis Of Glioma By Acting On VEGFA Through Targeting LRIG2

Background

Glioma is a common malignant tumor of the human central nervous system, and the pathological characteristics include invasive growth, angiogenesis, and so on. Ectopic expression of miR-503 works as a critical factor in cancer cell proliferation, migration, and capillary-like tube formation. The potential mechanisms of miR-503 in angiogenesis of glioma cells are still not reported.

Methods

The expression levels of miR-503, LRIG2, and VEGFA mRNA and protein were performed by quantitative reverse transcription-PCR or Western blot assay. Dual-Luciferase reporter gene assay was used to determine the interaction between miR-503 and LRIG2. The concentration of VEGFA was measured using the ELISA method. The cell proliferation, migration, and angiogenesis of cocultured HCMEC/D3 cells were analyzed by MTT assay, transwell detection, and tube formation assay, respectively.

Results

The expression levels of LRIG2 and VEGFA were reduced in glioma cells with miR-503 overexpression and enhanced with miR-503 inhibition. Moreover, cell proliferation, migration, and angiogenesis of cocultured HCMEC/D3 cells were alleviated with miR-503 mimics transfection. VEGFA and miR-503 inhibitor promoted cell proliferation, cell migration, and angiogenesis. Luciferase reporter gene assay revealed that miR-503 could directly target LRIG2. Furthermore, knockdown of LRIG2 or addition of VEGF inhibitor bevacizumab could abrogate the effect of miR-503 inhibitor on VEGFA expression, as well as the promotion of cell proliferation, migration, and angiogenesis.

Conclusion

MiR-503 mediated LRIG2 suppression and regulated the expression of VEGFA, thereby reducing cell proliferation, migration, and angiogenesis of glioma cells. These results provide new insight into the action mechanism of miR-503-modulated signaling pathway in angiogenesis of glioma cells.

Marked TGF-β-regulated miRNA expression changes in both COPD and control lung fibroblasts

COPD is associated with disturbed tissue repair, possibly due to TGF-β-regulated miRNA changes in fibroblasts. Our aim was to identify TGF-β-regulated miRNAs and their differential regulation and expression in COPD compared to control fibroblasts. Small RNA sequencing was performed on TGF-β-stimulated and unstimulated lung fibroblasts from 15 COPD patients and 15 controls. Linear regression was used to identify TGF-β-regulated and COPD-associated miRNAs. Interaction analysis was performed to compare miRNAs that responded differently to TGF-β in COPD and control. Re-analysis of previously generated Ago2-IP data and Enrichr were used to identify presence and function of potential target genes in the miRNA-targetome of lung fibroblasts. In total, 46 TGF-β-regulated miRNAs were identified in COPD and 86 in control fibroblasts (FDR < 0.05). MiR-27a-5p was the most significantly upregulated miRNA. MiR-148b-3p, miR-589-5p and miR-376b-3p responded differently to TGF-β in COPD compared to control (FDR < 0.25). MiR-660-5p was significantly upregulated in COPD compared to control (FDR < 0.05). Several predicted targets of miR-27a-5p, miR-148b-3p and miR-660-5p were present in the miRNA-targetome, and were mainly involved in the regulation of gene transcription. In conclusion, altered TGF-β-induced miRNA regulation and differential expression of miR-660-5p in COPD fibroblasts, may represent one of the mechanisms underlying aberrant tissue repair and remodelling in COPD.

Chemokines in COPD: From Implication to Therapeutic Use

: Chronic Obstructive Pulmonary Disease (COPD) represents the 3rd leading cause of death in the world. The underlying pathophysiological mechanisms have been the focus of extensive research in the past. The lung has a complex architecture, where structural cells interact continuously with immune cells that infiltrate into the pulmonary tissue. Both types of cells express chemokines and chemokine receptors, making them sensitive to modifications of concentration gradients. Cigarette smoke exposure and recurrent exacerbations, directly and indirectly, impact the expression of chemokines and chemokine receptors. Here, we provide an overview of the evidence regarding chemokines involvement in COPD, and we hypothesize that a dysregulation of this tightly regulated system is critical in COPD evolution, both at a stable state and during exacerbations. Targeting chemokines and chemokine receptors could be highly attractive as a mean to control both chronic inflammation and bronchial remodeling. We present a special focus on the CXCL8-CXCR1/2, CXCL9/10/11-CXCR3, CCL2-CCR2, and CXCL12-CXCR4 axes that seem particularly involved in the disease pathophysiology.

Characterization of MicroRNA and Gene Expression Profiles Following Ricin Intoxication

Ricin, derived from the castor bean plant, is a highly potent toxin, classified as a potential bioterror agent. Current methods for early detection of ricin poisoning are limited in selectivity. MicroRNAs (miRNAs), which are naturally occurring, negative gene expression regulators, are known for their tissue specific pattern of expression and their stability in tissues and blood. While various approaches for ricin detection have been investigated, miRNAs remain underexplored. We evaluated the effect of pulmonary exposure to ricin on miRNA expression profiles in mouse lungs and peripheral blood mononuclear cells (PBMCs). Significant changes in lung tissue miRNA expression levels were detected following ricin intoxication, specifically regarding miRNAs known to be involved in innate immunity pathways. Transcriptome analysis of the same lung tissues revealed activation of several immune regulation pathways and immune cell recruitment. Our work contributes to the understanding of the role of miRNAs and gene expression in ricin intoxication.

The roles of microRNAs in the pathogenesis of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by a progressive and irreversible airflow obstruction, with an abnormal lung function. The etiology of COPD correlates with complex interactions between environmental and genetic determinants. However, the exact pathogenesis of COPD is obscure although it involves multiple aspects including oxidative stress, imbalance between proteolytic and anti-proteolytic activity, immunity and inflammation, apoptosis, and repair and destruction in both airways and lungs. Many genes have been demonstrated to be involved in those pathogenic processes of this disease in patients exposed to harmful environmental factors. Previous reports have investigated promising microRNAs (miRNAs) to disclose the molecular mechanisms for COPD development induced by different environmental exposure and genetic predisposition encounter, and find some potential miRNA biomarkers for early diagnosis and treatment targets of COPD. In this review, we summarized the expression profiles of the reported miRNAs from studies of COPD associated with environmental risk factors including cigarette smoking and air pollution exposures, and provided an overview of roles of those miRNAs in the pathogenesis of the disease. We also highlighted the potential utility and limitations of miRNAs serving as diagnostic biomarkers and therapeutic targets for COPD.

MiR-503 suppresses hypoxia-induced proliferation, migration and angiogenesis of endothelial progenitor cells by targeting Apelin

Endothelial progenitor cells (EPCs) are of great importance in the process of endogenous blood vessel repair to maintain endothelial integrity and have been applied in a wide range of models of ischemic diseases. MicroRNAs represent a class of non-protein coding endogenous RNAs with 19-24 nucleotides in length and serve an important role in multiple physiological and pathological processes, including angiogenesis. It has been reported that miR-503 reduces angiogenesis in tumorigenesis. However, to our knowledge, the precise role of miR-503 in the regulation of EPCs remains unclear. In the current study, we found that the expression of miR-503 was decreased in mouse bone marrow derived EPCs under the hypoxic condition. Importantly, upregulation of miR-503 suppressed the proliferation, migration and capillary-like tube formation of EPCs induced by hypoxia. Furthermore, a dual luciferase reporter assay showed that Apelin, an endogenous ligand of the G protein-coupled receptor APJ, was a direct target of miR-503 and overexpression of miR-503 significantly inhibited the protein level of Apelin in EPCs. Moreover, hypoxia treatment enhanced the expression of Apelin in EPCs. Meanwhile ectopic expression of Apelin promoted cellular proliferation, migration and tube formation of EPCs in vitro. In summary, our results indicate that miR-503 regulates proliferation, migration and angiogenesis of EPCs by targeting Apelin.

Bioinformatics-based identification of potential microRNA biomarkers in frequent and non-frequent exacerbators of COPD

Objectives

MicroRNAs (miRNAs) play essential roles in the development of COPD. In this study, we aimed to identify and validate potential miRNA biomarkers in frequent and non-frequent exacerbators of COPD patients using bioinformatic analysis.

Materials and methods

The candidate miRNA biomarkers in COPD were screened from Gene Expression Omnibus (GEO) dataset and identified using GEO2R online tool. Then, we performed bioinformatic analyses including target prediction, gene ontology (GO), pathway enrichment analysis and construction of protein–protein interaction (PPI) network. Furthermore, the expression of the identified miRNAs in peripheral blood monocular cells (PBMCs) of COPD patients was validated using quantitative real-time polymerase chain reaction (qRT-PCR).

Results

MiR-23a, miR-25, miR-145 and miR-224 were identified to be significantly downregulated in COPD patients compared with healthy controls. GO analysis showed the four miRNAs involved in apoptotic, cell differentiation, cell proliferation and innate immune response. Pathway analysis showed that the targets of these miRNAs were associated with p53, TGF-β, Wnt, VEGF and MAPK signal pathway. In healthy controls, the miR-25 and miR-224 levels were significantly decreased in smokers compared with nonsmokers (P<0.001 and P<0.05, respectively). In COPD patients, the levels of miR-23a, miR-25, miR-145 and miR-224 were associated with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages. Notably, miR-23a and miR-145 were significantly elevated in non-frequent exacerbators compared with frequent exacerbators (P<0.05), and miR-23a showed higher area under the receiver–operator characteristic curve (AUROC) than miR-145 (0.707 vs 0.665, P<0.05).

Conclusion

MiR-23a, miR-25, miR-145 and miR-224 were associated with the development of COPD, and miR-23a might be a potential biomarker for discriminating the frequent exacerbators from non-frequent exacerbators.