miR-223: A Key Regulator in the Innate Immune Response in Asthma and COPD

MicroRNA Monitoring in Human Alveolar Macrophages from Patients with Smoking-Related Lung Diseases: A Preliminary Study

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that is commonly considered to be a potent driver of non-small cell lung cancer (NSCLC) development and related mortality. A growing body of evidence supports a role of the immune system, mainly played by alveolar macrophages (AMs), in key axes regulating the development of COPD or NSCLC phenotypes in response to harmful agents. MicroRNAs (miRNAs) are small non-coding RNAs that influence most biological processes and interfere with several regulatory pathways. The purpose of this study was to assess miRNA expression patterns in patients with COPD, NSCLC, and ever- or never-smoker controls to explore their involvement in smoking-related diseases. Bronchoalveolar lavage (BAL) specimens were collected from a prospective cohort of 43 sex-matched subjects to determine the expressions of hsa-miR-223-5p, 16-5p, 20a-5p, -17-5p, 34a-5p and 106a-5p by RT-PCR. In addition, a bioinformatic analysis of miRNA target genes linked to cancer was performed. Distinct and common miRNA expression levels were identified in each pathological group, suggesting their possible role as an index of NSCLC or COPD microenvironment. Moreover, we identified miRNA targets linked to carcinogenesis using in silico analysis. In conclusion, this study identified miRNA signatures in AMs, allowing us to understand the molecular mechanisms underlying smoking-related conditions and potentially providing new insights for diagnosis or pharmacological treatment.

Epigenetic processes involved in response to pesticide exposure in human populations: a systematic review and meta-analysis

In recent decades, the use of pesticides in agriculture has increased dramatically. This has resulted in these substances being widely dispersed in the environment, contaminating both exposed workers and communities living near agricultural areas and via contaminated foodstuffs. In addition to acute poisoning, chronic exposure to pesticides can lead to molecular changes that are becoming better understood. Therefore, the aim of this study was to assess, through a systematic review of the literature, what epigenetic alterations are associated with pesticide exposure. We performed a systematic review and meta-analysis including case-control, cohort and cross-sectional observational epidemiological studies to verify the epigenetic changes, such as DNA methylation, histone modification and differential microRNA expression, in humans who had been exposed to any type of pesticide. Articles published between the years 2005 and 2020 were collected. Two different reviewers performed a blind selection of the studies using the Rayyan QCRI software. Post-completion, the data of selected articles were extracted and analyzed. Most of the 28 articles included evaluated global DNA methylation levels, and the most commonly reported epigenetic modification in response to pesticide exposure was global DNA hypomethylation. Meta-analysis revealed a significant negative correlation between Alu methylation levels and β-hexachlorocyclohexane, p,p'-dichlorodiphenyldichloroethane and p,p'-dichlorodiphenylethylene levels. In addition, some specific genes were reported to be hypermethylated in promoter regions, such as CDKN2AIGF2, WRAP53α and CDH1, while CDKN2B and H19 were hypomethylated due to pesticide exposure. The expression of microRNAs was also altered in response to pesticides, as miR-223, miR-518d-3p, miR-597, miR-517b and miR-133b that are associated with many human diseases. Therefore, this study provides evidence that pesticide exposure could lead to epigenetic modifications, possibly altering global and gene-specific methylation levels, epigenome-wide methylation and microRNA differential expression.

The role of extracellular vesicles in COPD and potential clinical value

Chronic obstructive pulmonary disease (COPD) is a heterogeneous lung disease and a major health burden worldwide. Extracellular vesicles (EVs) are nanosized vesicles which possess a lipid bilayer structure that are secreted by various cells. They contain a variety of bioactive substances, which can regulate various physiological and pathological processes and are closely related to the development of diseases. Recently, EVs have emerged as a novel tool for intercellular crosstalk, which plays an essential role in COPD development. This paper reviews the role of EVs in the development of COPD and their potential clinical value, in order to provide a reference for further research on COPD.

Extracellular vesicles in acute respiratory distress syndrome: Understanding protective and harmful signaling for the development of new therapeutics

Acute respiratory distress syndrome (ARDS) is a severe respiratory condition characterized by increased lung permeability, hyper-inflammatory state, and fluid leak into the alveolar spaces. ARDS is a heterogeneous disease, with multiple direct and indirect causes that result in a mortality of up to 40%. Due to the ongoing Covid-19 pandemic, its incidence has increased up to ten-fold. Extracellular vesicles (EVs) are small liposome-like particles that mediate intercellular communication and play a major role in ARDS pathophysiology. Indeed, they participate in endothelial barrier dysfunction and permeability, neutrophil, and macrophage activation, and also in the development of a hypercoagulable state. A more thorough understanding of the variegated and cell-specific functions of EVs may lead to the development of safe and effective therapeutics. In this review, we have collected evidence of EVs role in ARDS, revise the main mechanisms of production and internalization and summarize the current therapeutical approaches that have shown the ability to modulate EV signaling.

miR‑186‑5p regulates the inflammatory response of chronic obstructive pulmonary disorder by targeting HIF‑1α

Chronic obstructive pulmonary disorder (COPD) is a chronic respiratory disease that is a major cause of morbidity and mortality worldwide. Previous studies have shown that miR‑186‑5p expression is significantly increased in COPD and is involved in multiple physiological and pathological processes. However, the role of miRNA‑186‑5p in the inflammatory response of COPD remains unclear. In this study, an in vitro model of COPD was established using lipopolysaccharide (LPS)‑induced human bronchial epithelial cells (BEAS‑2B). CCK‑8 assays, flow cytometry, and a Muse cell analyzer were used to determine cell viability, cell cycle distribution, and apoptosis, respectively. The production of TNF‑α and IL‑6 were measured by ELISA. Reverse‑transcription‑quantitative PCR and western blotting were used to analyze mRNA and protein expression levels. The targeting relation between miR‑186‑5p and HIF‑1α was discovered using dual‑luciferase reporter assays. The results showed that transfection of miR‑186‑5p inhibitor inhibited cell proliferation and promoted cell apoptosis in the LPS‑induced BEAS‑2B cells. Inhibition of miR‑186‑5p markedly increased the levels of TNF‑α and IL‑6. miR‑186‑5p directly targeted and negatively regulated HIF‑1α expression. In addition, inhibition of miR‑186‑5p increased the expression of the NF‑κB pathway protein p‑p65. In conclusion, it was found that inhibiting miR‑186‑5p may improve inflammation of COPD through HIF‑1α in LPS‑induced BEAS‑2B cells, possibly by regulating NF‑κB signaling. These findings provide a novel potential avenue for the clinical management of COPD. Future research is required to determine the mechanism of the interaction between miR‑186‑5p and HIF‑1α in COPD.

Different Transcriptome Features of Peripheral Blood Mononuclear Cells in Non-Emphysematous Chronic Obstructive Pulmonary Disease

Non-emphysematous chronic obstructive pulmonary disease (COPD), which is defined based on chest computed tomography findings, presented different transcriptome features of peripheral blood mononuclear cells (PBMCs) compared with emphysematous COPD. Enrichment analysis of transcriptomic data in COPD demonstrated that the "Hematopoietic cell lineage" pathway in Kyoto Encyclopedia of Genes and Genomes pathway analysis was highly upregulated, suggesting that cellular dynamic dysregulation in COPD lungs is affected by pathologically modified PBMCs. The differentially expressed genes (DEGs) upregulated in PBMCs reflected the disease state of non-emphysematous COPD. Upregulated DEGs such as XCL1, PRKCZ, TMEM102, CD200R1, and AQP1 activate T lymphocytes and eosinophils. Upregulating keratan sulfate biosynthesis and metabolic processes is associated with protection against the destruction of the distal airways. ITGA3 upregulation augments interactions with extracellular matrix proteins, and COL6A1 augments the profibrotic mast cell phenotype during alveolar collagen VI deposition. Upregulating HSPG2, PDGFRB, and PAK4 contributes to the thickening of the airway wall, and upregulating SERPINF1 expression explains the better-preserved vascular bed. Therefore, gene expression and pathway analysis in PBMCs in patients with non-emphysematous COPD represented type 2 immune responses and airway remodeling features. Therefore, these patients have asthmatic potential despite no clinical signs of asthma, in contrast to those with emphysematous COPD.

Non-coding RNA regulation of macrophage function in asthma

As a chronic respiratory disease, asthma is related to airway inflammation and remodeling. Macrophages are regarded as main innate immune cells in the airway that exert various functions like antigen recognition and presentation, phagocytosis, and pathogen clearance, playing a crucial role in the pathogeneses of asthma. Non-coding RNAs (ncRNAs), mainly include microRNA, long non-coding RNA and circular RNA, have been extensively investigated on the regulation of pathological process in asthma. Recent studies have indicated that ncRNA-regulated macrophages affect macrophage polarization, airway inflammation, immune regulation and airway remodeling, which suggests that modulating macrophages by ncRNAs may be a promising strategy for the treatment of asthma. This review summarizes the effect of macrophages in asthma and the regulatory mechanisms of ncRNAs, as well as focuses on the role of ncRNAs-regulated macrophages in asthma, for the development of novel therapeutic strategies in this disease.

MiRNA and Exosomal miRNA as New Biomarkers Useful to Phenotyping Severe Asthma

Severe asthma (SA) is a chronic inflammatory disease of the airways. Due to the extreme heterogeneity of symptoms, new biomarkers are currently needed. MiRNAs are non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. In biological fluids, miRNAs are contained within exosomes, vesicles capable of giving miRNAs considerable stability and resistance to degradation by RNAses. The main function attributed to the exosomes is intercellular communication. The goal of our study was to analyze intracellular and exosomal miRNAs in order to demonstrate their potential use as non-invasive biomarkers of asthma by showing, in particular, their role in SA. We detected miRNAs by qRT-PCR in both serum and serum-derived-exosomes of asthmatic patients and healthy controls. The levels of almost all analyzed intracellular miRNAs (miR-21, miR-223, and let-7a) were greater in asthmatic patients vs. healthy control, except for miR-223. In detail, miR-21 was greater in SA, while let-7a increased in mild-to-moderate asthma. On the other hand, in exosomes, all analyzed miRNAs were higher in SA. This study identified a series of miRNAs involved in SA, highlighting their potential role in asthma development and progression. These results need validation on a larger cohort.

Exosomal microRNA/miRNA Dysregulation in Respiratory Diseases: From Mycoplasma-Induced Respiratory Disease to COVID-19 and Beyond

Respiratory diseases represent a significant economic and health burden worldwide, affecting millions of individuals each year in both human and animal populations. MicroRNAs (miRNAs) play crucial roles in gene expression regulation and are involved in various physiological and pathological processes. Exosomal miRNAs and cellular miRNAs have been identified as key regulators of several immune respiratory diseases, such as chronic respiratory diseases (CRD) caused by Mycoplasma gallisepticum (MG), Mycoplasma pneumoniae pneumonia (MMP) caused by the bacterium Mycoplasma pneumoniae, coronavirus disease 2019 (COVID-19), chronic obstructive pulmonary disease (COPD), asthma, and acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Consequently, miRNAs seem to have the potential to serve as diagnostic biomarkers and therapeutic targets in respiratory diseases. In this review, we summarize the current understanding of the functional roles of miRNAs in the above several respiratory diseases and discuss the potential use of miRNAs as stable diagnostic biomarkers and therapeutic targets for several immune respiratory diseases, focusing on the identification of differentially expressed miRNAs and their targeting of various signaling pathways implicated in disease pathogenesis. Despite the progress made, unanswered questions and future research directions are discussed to facilitate personalized and targeted therapies for patients with these debilitating conditions.

Comparing the expression of MiR-223-NLRP3-IL-1β axis and serum IL-1β levels in patients with severe COVID-19 and healthy individuals

BACKGROUND AND AIM

The hyperactive nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a key factor for cytokine storm, chronic inflammation, and mortality in infected patients. On the subject of the regulation of the NLRP3-inflammasome activation, micro-ribonucleic acid (RNA)-223 (miR-223), among the major RNA molecules, has been thus far investigated in some inflammatory diseases along with interleukin-1 beta (IL-1β) and NLRP3. Against this background, the present study aimed to compare healthy individuals and patients with severe COVID-19 with reference to the alterations in the expression of the miR-223, NLRP3, and IL-1β axis and the serum IL-1β levels.

METHODS

In total, 40 patients with severe COVID-19, admitted to the Infectious Ward of Razi Hospital, Ahvaz, Iran, who were homogenous in terms of age (40 years old) and gender, were selected based on the inclusion and exclusion criteria. The real-time polymerase chain reaction (RT-PCR) technique was then applied to assess the expression of the miR-223, NLRP3, and IL-1β genes, and enzyme-linked immunosorbent assay (ELISA) was then utilized to evaluate the serum IL-1β levels, using patients' blood samples. Moreover, inflammatory biochemical markers of the participants were collected and recorded RESULTS: According to the study results, the IL-1β expression was 3.9 times higher in the patients with COVID-19, compared with the control group (p = 0.0005). The NLRP3 expression was also 6.04 times greater in the infected patients, compared with the healthy individuals (p < 0.0001). On the other hand, the miR-223 expression was 5.37 times lower in the case group, compared with the controls (p = 0.04).

CONCLUSION

The study findings indicated the potential role of miR-223 and the dysregulation of NLRP3 inflammasome followed by IL-1β, as a regulatory factor in the pathogenesis of COVID-19, like that in other inflammatory diseases.

Exosomal miR-17-5p, miR-146a-3p, and miR-223-3p Correlate with Radiologic Sequelae in Survivors of COVID-19-Related Acute Respiratory Distress Syndrome

We investigated the association between circulating microRNAs (miRNAs) potentially involved in the lung inflammatory process and fibrosis development among COVID-19-related acute respiratory distress syndrome (ARDS) survivors. At 4 ± 2 months from clinical recovery, COVID-19-related ARDS survivors matched for age, sex, and clinical characteristics underwent chest high-resolution computerized tomography (HRCT) and were selected based on imaging pattern evolution into fully recovered (N = normal), pulmonary opacities (PO) and fibrosis-like lesions (FL). Based on the previous literature, we performed plasma miRNA profiling of exosomal miRNAs belonging to the NLRP3-inflammasome platform with validated (miR-17-5p, miR-223-3p) and putative targets (miR-146a-5p), miRNAs involved in the post-transcriptional regulation of acute phase cytokines (miR128-3p, miR3168, miR125b-2-3p, miR106a-5p), miRNAs belonging to the NLRP4-inflammasome platform (miR-141-3p) and miRNAs related to post-transcriptional regulation of the fibrosis process (miR-21-5p). miR-17-5p, miR-223-3p, and miR-146a-5p were significantly down-regulated in patients with FL when compared to patients with PO. miR-146a-5p was also down-regulated in patients with FL than in N. The expression of the remaining miRNAs did not differ by group. In patients with long-term pulmonary radiological sequelae following COVID-19-related ARDS, a down-regulation of miR-17-5p, miR-146a-3p, and miR-223-3p correlated to fibrosis development in patients showing persistent hyper-reactivity to inflammatory stimulation. Our results support the hypothesis that NLRP3-Inflammasome could be implicated in the process of fibrotic evolution of COVID-19-associated ARDS.

Long non coding RNAs reveal important pathways in childhood asthma: a future perspective

Asthma is a long-term inflammatory disease of the airways of the lungs refers changes that occur in conjunction with, or as a result of, chronic airway inflammation. Airway remodeling the subsequent of inflammation constitutes cellular and extracellular matrix changes in the wall airways, epithelial-to-mesenchymal-transition and airway smooth muscle cell proliferation. Diseases often begin in childhood and despite extensive research, causative pathogenic mechanisms still remain unclear. Transcriptome analysis of childhood asthma reveals distinct gene expression profiles of Long noncoding RNAs which have been reported to play a central regulatory role in various aspects of pathogenesis, clinical course and treatment of asthma. We briefly review current understanding of lnc-RNA dysregulation in children with asthma, focusing on their complex role in the inflammation, cell proliferation and remodeling of airway to guide future researches. We found that the lnc-RNAs increases activity of several oncogenes such c-Myc, Akt, and ERK and various signaling pathways such as MAPK (PI3K, Ras, JNK and p38), NF-κB and Wnt and crosstalk between these pathways by TGFβ, β-catenin, ERK and SKP2. Moreover, two different signal transduction pathways, Wnt and Notch1, can be activated by two lnc-RNAs through sponging the same miRNA for exacerbation cell proliferation.

miR-223: a key regulator of pulmonary inflammation

Small noncoding RNAs, known as microRNAs (miRNAs), are vital for the regulation of diverse biological processes. miR-223, an evolutionarily conserved anti-inflammatory miRNA expressed in cells of the myeloid lineage, has been implicated in the regulation of monocyte-macrophage differentiation, proinflammatory responses, and the recruitment of neutrophils. The biological functions of this gene are regulated by its expression levels in cells or tissues. In this review, we first outline the regulatory role of miR-223 in granulocytes, macrophages, endothelial cells, epithelial cells and dendritic cells (DCs). Then, we summarize the possible role of miR-223 in chronic obstructive pulmonary disease (COPD), acute lung injury (ALI), coronavirus disease 2019 (COVID-19) and other pulmonary inflammatory diseases to better understand the molecular regulatory networks in pulmonary inflammatory diseases.

Expression Patterns of MiR-125a and MiR-223 and Their Association with Diabetes Mellitus and Survival in Patients with Non-ST-Segment Elevation Acute Coronary Syndrome

Background: MicroRNAs (miRNA, miR) are small, non-coding RNAs which have become increasingly relevant as diagnostic and prognostic biomarkers. The objective of this study was the investigation of blood-derived miRNAs and their link to long-term all-cause mortality in patients who suffered from non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Methods: This study was an observational prospective study, which included 109 patients with NSTE-ACS. Analysis of the expression of miR-125a and miR-223 was conducted by polymerase chain reaction (PCR). The follow-up period comprised a median of 7.5 years. Long-term all-cause mortality was considered as the primary endpoint. Adjusted Cox-regression analysis was performed for prediction of events. Results: Increased expression of miR-223 (>7.1) at the time point of the event was related to improved long-term all-cause survival (adjusted (adj.) hazard ratio (HR) = 0.09, 95% confidence interval (95%CI): 0.01-0.75; p = 0.026). The receiver operating characteristic (ROC) analysis provided sufficient c-statistics (area under the curve (AUC) = 0.73, 95%CI: 0.58-0.86; p = 0.034; negative predictive value of 98%) for miR-223 to predict long-term all-cause survival. The Kaplan-Meier time to event analysis showed a separation of the survival curves between the groups at an early stage (log rank p = 0.015). Higher plasma miR-125a levels were found in patients with diabetes mellitus vs. in those without (p = 0.010). Furthermore, increased miR-125a expression was associated with an elevated HbA1c concentration. Conclusions: In this hypothesis-generating study, higher values of miR-223 were related to improved long-term survival in patients after NSTE-ACS. Larger studies are required in order to evaluate whether miR-223 can be used as a suitable predictor for long-term all-cause mortality.

Sex-biased expression of selected chromosome x-linked microRNAs with potent regulatory effect on the inflammatory response in children with cystic fibrosis: A preliminary pilot investigation

Previous studies have reported sex disparity in cystic fibrosis (CF) disease, with females experiencing more pulmonary exacerbations and frequent microbial infections resulting in shorter survival expectancy. This concerns both pubertal and prepubertal females, which is in support to the prominent role of gene dosage rather than the hormonal status. The underlying mechanisms are still poorly understood. The X chromosome codes for a large number of micro-RNAs (miRNAs) that play a crucial role in the post-transcriptional regulation of several genes involved in various biological processes, including inflammation. However, their level of expression in CF males and females has not been sufficiently explored. In this study, we compared in male and female CF patients the expression of selected X-linked miRNAs involved in inflammatory processes. Cytokine and chemokine profiles were also evaluated at both protein and transcript levels and cross-analyzed with the miRNA expression levels. We observed increased expression of miR-223-3p, miR-106a-5p, miR-221-3p and miR-502-5p in CF patients compared to healthy controls. Interestingly, the overexpression of miR-221-3p was found to be significantly higher in CF girls than in CF boys and this correlates positively with IL-1β. Moreover, we found a trend toward lower expression in CF girls than in CF boys of suppressor of cytokine signaling 1 (SOCS1) and the ubiquitin-editing enzyme PDLIM2, two mRNA targets of miR-221-3p that are known to inhibit the NF-κB pathway. Collectively, this clinical study highlights a sex-bias in X-linked miR-221-3p expression in blood cells and its potential contribution to sustaining a higher inflammatory response in CF girls.

The relationship between residential exposure to atmospheric pollution and circulating miRNA in adults living in an urban area in northern France

INTRODUCTION

MicroRNAs are epigenetic regulatory factors capable of silencing the expression of target genes and might mediate the effects of air pollution on health. The objective of the present population-based study was to investigate the association between microRNA expression and long-term, residential exposure to atmospheric PM₁₀ and NO₂.

METHOD

We included 998 non-smoking adult participants from the cross-sectional ELISABET survey (2010-2014) in the Lille urban area of France. The mean residential annual pollution levels were estimated with an atmospheric dispersion modelling system. Ten microRNAs were selected on the basis of the literature data, together with two housekeeping microRNAs (miR-93-5p and miR-191-5p) and were quantified with RT-qPCRs. Multivariate linear regression models were used to study the association between microRNAs and air pollution. The threshold for statistical significance (after correction for the FDR) was set to p < 0.1.

RESULTS

The mean annual exposure between 2011 and the year of inclusion was 26.4 ± 2.0 µg/m³ for PM₁₀ and 24.7 ± 5.1 µg/m³ for NO₂. Each 2 µg/m³ increment in PM₁₀ exposure was associated with an 8.6% increment (95%CI [3.1; 14.3]; p_FDR = 0.019) in miR-451a expression. A 5 µg/m³ increment in NO₂ exposure was associated with a 5.3% increment ([0.7; 10]; p_FDR = 0.056) in miR451a expression, a 3.6% decrement (95%CI [-6.1; -1.1]; p_FDR = 0.052) in miR-223-3p expression, a 3.8% decrement (95%CI[-6.8; -0.7]; p_FDR = 0.079) in miR-28-3p expression, a 4.3% decrement (95%CI [-7.7; -0.8]; p_FDR = 0.055) in miR-146a-5p expression, and a 4.0% decrement (95% CI[-7.4; -0.4]; p_FDR = 0.059) in miR-23a-5p expression. The difference between the two housekeeping microRNAs miR-93-5p and miR-191-5p was also associated with PM₁₀ and NO₂ exposure.

CONCLUSION

Our results suggest that circulating miRNAs are potentially valuable biomarkers of the effects of air pollution.

Immunotolerance of dairy heifers in response to repeated exposure to bacterial lipopolysaccharide endotoxin

Dairy cattle face a variety of stressful events on a daily basis. More specifically, climate change has resulted in more frequent heat stress events that increase the incidence of chronic bacterial infections by inducing conditions like leaky gut syndrome, whereby the integrity of the intestinal epithelium is compromised allowing for luminal bacterial lipopolysaccharide (LPS) endotoxin to infiltrate the host's bloodstream resulting in acute or chronic systemic stimulation of the innate immune system. Repeated exposure to LPS over a short period of time is reported to induce immunotolerance within the host. This LPS tolerance is an essential immunohomeostatic response that can protect against over activation of the inflammatory response during subsequent exposure to LPS. In the present study, Holstein calves (n = 20) were initially stress challenged with either saline, or 100, 200 or 400 ng/kg of LPS administered intramuscular, and again re-challenged with 200 ng/kg of LPS 2-weeks later. Serum was collected every 2 hr for 6 hr to profile changes in circulatory stress biomarkers after the repeated LPS exposures. Heifers that were initially challenged with 100, 200 and 400 ng/kg of LPS demonstrated significantly attenuated cortisol responses in the second challenge (p < 0.01, 0.01 and 0.05, respectively), whereas control animals who previously received saline demonstrated a strong cortisol response at 2 hr after receiving 200 ng/kg of LPS (p < 0.05). The cytokine/chemokine (IL-6, CCL2, CCL3 and CCL4) responses were also attenuated during the LPS rechallenge (p < 0.05). Finally, microRNA expression profiles were determined to assess the epigenetic response to repeated LPS exposure. Interestingly, miR-31 and miR-223 were downregulated in response to the second LPS challenge. The present study demonstrates the dynamic nature of the stress response in dairy cattle as it relates to the development of LPS tolerance. Understanding the roles of various stress biomarkers in the context of innate immune cell tolerance is essential for evaluating their impact on immune system homeostasis.

The miR-124-3p regulates the allergic airway inflammation and remodeling in an ovalbumin-asthmatic mouse model by inhibiting S100A4

OBJECTIVE

Asthma is a chronic respiratory disease with an increasing incidence every year. microRNAs (miRNAs) have been demonstrated to have implications for asthma. However, limited information is available regarding the effect of miR-124-3p on this disease. Therefore, this study aimed to explore the possible effects of miR-124-3p and S100A4 on inflammation and epithelial-mesenchymal transition (EMT) in asthma using mouse models.

METHOD

Ovalbumin was used to induce asthmatic mouse models. Lung injury in mouse models was assessed, and the bronchoalveolar lavage fluid of mice was collected to determine the number of eosinophilic granulocytes and assess inflammation. The expression levels of miR-124-3p, S100A4, E-cadherin, N-cadherin, Snail1, vimentin, and TGF-β1/Smad2 signaling pathway-related proteins were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. In vitro experiments, cells were transfected with miR-124-3p mimics or inhibitors to test the expression of S100A4 by RT-qPCR and western blot analysis, and the mutual binding of miR-124-3p and S100A4 was validated by dual-luciferase reporter gene assay.

RESULTS

Overexpression of miR-124-3p or inhibition of S100A4 expression attenuated bronchial mucus secretion and collagenous fibers and suppressed inflammatory cell infiltration. Additionally, upon miR-124-3p overexpression or S100A4 suppression, eosinophilic granulocytes were decreased, interleukin-4 (IL-4) and IL-13 expression levels were reduced in the bronchoalveolar lavage fluid, serum total IgE level was reduced, and the TGF-β1/Smad2 signaling pathway was suppressed. Mechanically, a dual-luciferase reporter gene assay verified the binding relationship between miR-124-3p and S100A4.

CONCLUSION

miR-124-3p can negatively target S100A4 to attenuate inflammation in asthmatic mouse models by suppressing the EMT process and the TGF-β/smad2 signaling pathway.

Wenshen Yiqi Keli Mitigates the Proliferation and Migration of Cigarette Smoke Extract-Induced Human Airway Smooth Muscle Cells through miR-155/FoxO3a Axis

Some domestic scholars revealed the effectiveness of Wenshen Yiqi Keli (WSYQKL) on chronic obstructive pulmonary disease (COPD). However, the exact mechanism of WSYQKL on COPD is fuzzy and needs further research. We adopted UPLC-Q/TOF-MS to analyze the chemical components of WSYQKL. In in vitro experiments, human airway smooth muscle cells (hASMCs) were intervened with 2.5% cigarette smoke extract (CSE), medicine serum of WSYQKL, miR-155 mimic, and FoxO3a silencing. Cell viability, proliferation, migration, and the expressions of miR-155, PCNA, Ki67, p21, p27, and FoxO3a were examined by cell counting kit-8, EdU staining, Transwell assay, scarification assay, qRT-PCR, immunol cytochemistry, and western blot, respectively. The association between miR-155 and FoxO3a was assessed by database and luciferase reporter gene analysis. We identified 47 kinds of chemical compositions of WSYQKL in ESI+ mode and 42 kinds of components of WSYQKL in ESI− mode. The medicine serum of WSYQKL strongly alleviated the proliferation and migration of hASMCs induced by CSE in a concentration-dependent manner. The medicine serum of WSYQKL enhanced the levels of p21, p27, and FoxO3a and weakened PCNA and Ki67 levels in hASMCs induced by CSE with the increase of concentration. MiR-155 mimic or FoxO3a silencing notably advanced CSE-treated HASMC viability, proliferation, migration, and the levels of PCNA and Ki67 and downregulated the levels of p21, p27, and FoxO3a in CSE-triggered hASMCs, which was reversed by WSYQKL-containing serum. Our results described that WSYQKL alleviated the proliferation and migration of hASMCs induced by CSE by modulating the miR-155/FoxO3a axis.

Plasma Extracellular Vesicle miRNA Profiles Distinguish Chronic Obstructive Pulmonary Disease Exacerbations and Disease Severity

Purpose

Molecular biomarkers for chronic obstructive pulmonary disease (COPD) severity have been difficult to identify. We aimed to assess extracellular vesicle miRNAs’ potential as a blood biomarker in discriminating disease severity in participants with COPD.

Patients and Methods

Plasma extracellular vesicles (EVs) were obtained from two COPD cohorts (n = 20 during an exacerbation event, n = 20 during stable state), with varying disease severity (GOLD stages). The miRCURY LNA miRNA Serum/Plasma assay, specific to 179 targets, was used to evaluate EV miRNA expression. The miRNAs that were significantly dysregulated were further assessed for discriminatory power using ROC curve analysis, as well as their role in relevant biological pathways.

Results

One miRNA was significantly dysregulated between moderate GOLD participants compared to severe/very severe GOLD participants, with an AUC of 0.798, p = 0.01 for miR-374b-5p. Five miRNAs were significantly dysregulated between exacerbating and stable COPD participants, with miR-223-3p resulting in the highest AUC (0.755, p = 0.006) for a single miRNA, with a combination of three miRNAs (miR-92b-3p, miR-374a-5p and miR-106b-3p) providing the highest discriminatory power (AUC 0.820, p = 0.001). The “cytokine–cytokine receptor interaction” (hsa04060 pathway) was the most significant KEGG pathway enriched for three out of the five miRNAs associated with COPD exacerbations.

Conclusion

This initial small-scale study suggests that the bioactive cargo (miRNAs) in plasma EVs holds specific biological information for the severity of airflow obstruction and COPD exacerbations, warranting further investigation.

Modes of action and diagnostic value of miRNAs in sepsis

Sepsis is a clinical syndrome defined as a dysregulated host response to infection resulting in life-threatening organ dysfunction. Sepsis is a major public health concern associated with one in five deaths worldwide. Sepsis is characterized by unbalanced inflammation and profound and sustained immunosuppression, increasing patient susceptibility to secondary infections and mortality. microRNAs (miRNAs) play a central role in the control of many biological processes, and deregulation of their expression has been linked to the development of oncological, cardiovascular, neurodegenerative and metabolic diseases. In this review, we discuss the role of miRNAs in sepsis pathophysiology. Overall, miRNAs are seen as promising biomarkers, and it has been proposed to develop miRNA-based therapies for sepsis. Yet, the picture is not so straightforward because of the versatile and dynamic features of miRNAs. Clearly, more research is needed to clarify the expression and role of miRNAs in sepsis, and to promote the use of miRNAs for sepsis management.

High-Density Lipoproteins: A Role in Inflammation in COPD

Chronic obstructive pulmonary disease (COPD) is a widespread disease associated with high rates of disability and mortality. COPD is characterized by chronic inflammation in the bronchi as well as systemic inflammation, which contributes significantly to the clinically heterogeneous course of the disease. Lipid metabolism disorders are common in COPD, being a part of its pathogenesis. High-density lipoproteins (HDLs) are not only involved in lipid metabolism, but are also part of the organism’s immune and antioxidant defense. In addition, HDL is a versatile transport system for endogenous regulatory agents and is also involved in the removal of exogenous substances such as lipopolysaccharide. These functions, as well as information about lipoprotein metabolism disorders in COPD, allow a broader assessment of their role in the pathogenesis of heterogeneous and comorbid course of the disease.

MiR-7 Regulates Pathogen-Induced Immune Response via PAK1 in the Sea Cucumber Apostichopus japonicus

MicroRNA-7 (miR-7) is a highly conserved short non-coding RNA involved in various bioprocesses via the regulation of multiple target genes. To enrich our knowledge of the functions of miR-7 in innate immune regulation in echinoderms, we first investigated the targeting relationship between miR-7 and PAK1 in the sea cucumber Apostichopus japonicus and then explored the functions of miR-7, the PAK1 gene, and the miR-7/PAK1 axis in the pathogen-induced immune response of A. japonicus. Our results showed that miR-7 can bind to the 3ʹUTR of PAK1 and negatively regulate the expression of PAK1 in A. japonicus. Overexpression and inhibition of miR-7 and inhibition of the expression of PAK1 can alter phagocytosis, cellular agglutination, and lysozyme contents in A. japonicus. Both miR-7 and the PAK1 gene are involved in immune defense against Vibrio splendidus infection; the miR-7/AjPAK1 axis showed immune regulatory function at 48 to 72 h post-infection (hpi) after V. splendidus infection in A. japonicus. In summary, the results of this study established that miR-7 regulates the pathogen-induced immune response by targeting PAK1 in A. japonicus.

The Interaction Network of MicroRNAs with Cytokines and Signaling Pathways in Allergic Asthma

Allergic asthma is a complicated disease that is affected by many factors. Numerous cytokines and signaling pathways are attributed to the cause of asthma symptoms. MicroRNAs (miRNAs) are a group of small non-coding single-stranded RNA molecules that are involved in gene silencing and posttranscriptional regulation of gene expression by targeting mRNAs. In pathological conditions, altered expression of microRNAs differentially regulates cytokines and signaling pathways and therefore, can be the underlying reason for the pathogenesis of allergic asthma. Indeed, microRNAs participate in airway inflammation via inducing airway structural cells and activating immune responses by targeting cytokines and signaling pathways. Thus, to make a complete understanding of allergic asthma, it is necessary to investigate the communication network of microRNAs with cytokines and signaling pathways which is contributed to the pathogenesis of allergic asthma. Here, we shed light on this aspect of asthma pathology by Summarizing our current knowledge of this topic.

Chronic obstructive pulmonary disease and asthma: mesenchymal stem cells and their extracellular vesicles as potential therapeutic tools

Chronic lung diseases, such as chronic obstructive pulmonary disease (COPD) and asthma, are one of the most frequent causes of morbidity and mortality in the global. COPD is characterized by progressive loss of lung function through inflammation, apoptosis, and oxidative stress caused by chronic exposure to harmful environmental pollutants. Airway inflammation and epithelial remodeling are also two main characteristics of asthma. In spite of extensive efforts from researchers, there is still a great need for novel therapeutic approaches for treatment of these conditions. Accumulating evidence suggests the potential role of mesenchymal stem cells (MSCs) in treatment of many lung injuries due to their beneficial features including immunomodulation and tissue regeneration. Besides, the therapeutic advantages of MSCs are chiefly related to their paracrine functions such as releasing extracellular vesicles (EVs). EVs comprising exosomes and microvesicles are heterogeneous bilayer membrane structures loaded with various lipids, nucleic acids and proteins. Due to their lower immunogenicity, tumorigenicity, and easier management, EVs have appeared as favorable alternatives to stem cell therapies. Therefore, in this review, we provided an overview on the current understanding of the importance of MSCs and MSC-derived EVs from different sources reported in preclinical and clinical COPD and asthmatic models.

Neutrophil Extracellular Traps Mediate Acute Liver Failure in Regulation of miR-223/Neutrophil Elastase Signaling in Mice

BACKGROUND & AIMS

Marked enhancement of neutrophil infiltration in the liver is a hallmark of acute liver failure (ALF), a severe life-threatening disease with varying etiologies. However, the mechanisms and pathophysiological role corresponding to hepatic neutrophil infiltration during ALF development remain poorly characterized.

METHODS

Experimental ALF was induced in 10-week-old male microRNA-223 (miR-223) knockout (KO) mice, neutrophil elastase (NE) KO mice, and wild-type controls by intraperitoneal injection of galactosamine hydrochloride and lipopolysaccharide. Age-matched mice were injected with phosphate-buffered saline and served as vehicle controls.

RESULTS

Mouse liver with ALF showed evident formation of neutrophil extracellular traps (NETs), which were enhanced markedly in miR-223 KO mice. The blockade of NETs by pharmacologic inhibitor GSK484 significantly attenuated neutrophil infiltration and massive necrosis in mouse liver with ALF. ALF-related hepatocellular damage and mortality in miR-223 KO mice were aggravated significantly and accompanied by potentiated neutrophil infiltration in the liver when compared with wild-type controls. Transcriptomic analyses showed that miR-223 deficiency in bone marrow predominantly caused the enrichment of pathways involved in neutrophil degranulation. Likewise, ALF-induced hepatic NE enrichment was potentiated in miR-223 KO mice. Genetic ablation of NE blunted the formation of NETs in parallel with significant attenuation of ALF in mice. Pharmaceutically, pretreatment with the NE inhibitor sivelestat protected mice against ALF.

CONCLUSIONS

The present study showed the miR-223/NE axis as a key modulator of NETs, thereby exacerbating oxidative stress and neutrophilic inflammation to potentiate hepatocellular damage and liver necrosis in ALF development, and offering potential targets against ALF.

Immunomodulatory Properties of Human Breast Milk: MicroRNA Contents and Potential Epigenetic Effects

Infants who are exclusively breastfed in the first six months of age receive adequate nutrients, achieving optimal immune protection and growth. In addition to the known nutritional components of human breast milk (HBM), i.e., water, carbohydrates, fats and proteins, it is also a rich source of microRNAs, which impact epigenetic mechanisms. This comprehensive work presents an up-to-date overview of the immunomodulatory constituents of HBM, highlighting its content of circulating microRNAs. The epigenetic effects of HBM are discussed, especially those regulated by miRNAs. HBM contains more than 1400 microRNAs. The majority of these microRNAs originate from the lactating gland and are based on the remodeling of cells in the gland during breastfeeding. These miRNAs can affect epigenetic patterns by several mechanisms, including DNA methylation, histone modifications and RNA regulation, which could ultimately result in alterations in gene expressions. Therefore, the unique microRNA profile of HBM, including exosomal microRNAs, is implicated in the regulation of the genes responsible for a variety of immunological and physiological functions, such as FTO, INS, IGF1, NRF2, GLUT1 and FOXP3 genes. Hence, studying the HBM miRNA composition is important for improving the nutritional approaches for pregnancy and infant's early life and preventing diseases that could occur in the future. Interestingly, the composition of miRNAs in HBM is affected by multiple factors, including diet, environmental and genetic factors.

Unraveling the Pathogenesis of Asthma and Chronic Obstructive Pulmonary Disease Overlap: Focusing on Epigenetic Mechanisms

Asthma and COPD overlap (ACO) is characterized by patients presenting with persistent airflow limitation and features of both asthma and COPD. It is associated with a higher frequency and severity of exacerbations, a faster lung function decline, and a higher healthcare cost. Systemic inflammation in COPD and asthma is driven by type 1 T helper (Th1) and Th2 immune responses, respectively, both of which may contribute to airway remodeling in ACO. ACO-related biomarkers can be classified into four categories: neutrophil-mediated inflammation, Th2 cell responses, arachidonic acid-eicosanoids pathway, and metabolites. Gene–environment interactions are key contributors to the complexity of ACO and are regulated by epigenetic mechanisms, including DNA methylation, histone modifications, and non-coding RNAs. Thus, this review focuses on the link between epigenetics and ACO, and outlines the following: (I) inheriting epigenotypes without change with environmental stimuli, or epigenetic changes in response to long-term exposure to inhaled particles plus intermittent exposure to specific allergens; (II) epigenetic markers distinguishing ACO from COPD and asthma; (III) potential epigenetic drugs that can reverse oxidative stress, glucocorticoid insensitivity, and cell injury. Improved understanding of the epigenetic regulations holds great value to give deeper insight into the mechanisms, and clarify their implications for biomedical research in ACO.

Morus macroura Miq. Fruit extract protects against acetic acid-induced ulcerative colitis in rats: Novel mechanistic insights on its impact on miRNA-223 and on the TNFα/NFκB/NLRP3 inflammatory axis

Nod-like receptor pyrin domain-1 containing 3 (NLRP3) inflammasome/tumor necrosis factor alpha (TNFα)/nuclear factor kappa B (NFκB) inflammatory pathway is known to be involved in the pathogenesis of ulcerative colitis (UC). Inversely, miRNA-223 can exert counter-regulatory effect on NLRP3 expression. The mulberry tree (Morus macroura) fruit is attaining increased importance for its antioxidant and anti-inflammatory activity in addition to its high safety profile. Accordingly, we attempted to explore the possible protective effect of mulberry fruit extract (MFE) in acetic acid (AA)-induced UC rat model. Phytochemical constituents of MFE were characterized using high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). In the in vivo study, three doses of MFE were orally given for seven days before intra-rectal induction of UC by AA on day eight. Screening study revealed that MFE (300 mg/kg) significantly reduced macroscopic and microscopic UC scores. Biochemically, MFE ameliorated oxidative stress, levels of TNFR1, NLRP3, p-NFκB p65, TNFα, IL-1β, and IL-18, caspase-1 activity, but enhanced miRNA-223 expression. In conclusion, our study provided a novel protective impact for MFE against UC, in which miRNA-223 and TNFα/NFκB/NLRP3 pathway are involved. These results provide a promising step that might encourage further investigations of MFE as a protective agent in UC patients.

Characterizing the Inflammatory Microenvironment in K14-HPV16 Transgenic Mice: Mast Cell Infiltration and MicroRNA Expression

High-risk human papillomavirus (HPV) is the etiologic agent of several types of cancer. Mast cells’ role as either a driving or opposing force for cancer progression remains controversial. MicroRNAs are dysregulated in several HPV-induced cancers, and can influence mast cell biology. The aim of this study was to evaluate mast cell infiltration and to identify microRNAs potentially regulating this process. Transgenic male mice (K14-HPV16; HPV+) and matched wild-type mice (HPV−) received 7,12-Dimethylbenz[a]anthracene (DMBA) (or vehicle) over 17 weeks. Following euthanasia, chest skin and ear tissue samples were collected. Mast cell infiltration was evaluated by immunohistochemistry. MicroRNAs associated with mast cell infiltration were identified using bioinformatic tools. MicroRNA and mRNA relative expression was evaluated by RT-qPCR. Immunohistochemistry showed increased mast cell infiltration in HPV+ mice (p < 0.001). DMBA did not have any statistically significant influence on this distribution. Ear tissue of HPV+ mice showed increased mast cell infiltration (p < 0.01) when compared with chest skin samples. Additionally, reduced relative expression of miR-125b-5p (p = 0.008, 2−ΔΔCt = 2.09) and miR-223-3p (p = 0.013, 2−ΔΔCt = 4.42) seems to be associated with mast cell infiltration and increased expression of target gene Cxcl10. These results indicate that HPV16 may increase mast cell infiltration by down-regulating miR-223-3p and miR-125b-5p.

Diagnosis of Chronic Obstructive Pulmonary Disease and Regulatory Mechanism of miR-149-3p on Alveolar Inflammatory Factors and Expression of Surfactant Proteins A (SP-A) and D (SP-D) on Lung Surface Mediated by Wnt Pathway

Objective

To study the mechanism of chronic obstructive pulmonary disease (COPD) in diagnosing alveolar factors and analyze the effect of miR-149-3p on alveolar inflammatory factors and the expression of surfactant protein D (SP-D) and SP-A on the lung surface mediated by Wnt pathway.

Methods

Patients with stable COPD were taken as the research subjects, and healthy volunteers as the control group. Cardiac color Doppler ultrasound was adopted to measure the ventricular structure of patients. The ultrasound simulation method was introduced in the ultrasound imaging. The ultrasound image was processed based on the intelligent ultrasound simulation algorithm. The changes in the structure of the left and right ventricles were analyzed and compared in the two groups. The expression changes of miR-149-3p, Wnt1, β-catenin, RhoA, and Wnt5a in lung tissues of mice in three groups were detected, as well as the content of tumor necrosis factor- (TNF-) α, IL-1β, interleukin (IL-6), nuclear factor kB (NF-kB), and other inflammatory factors in bronchoalveolar tissues of mice in three groups.

Results

The position where the attenuation ratio was less than 0.92 in the experiment under the ultrasonic simulation algorithm had a gray value of 50. Compared with the control group, the right ventricular mass index of patients with stable COPD was statistically considerable (P < 0.05). In patients with stable COPD, the overall right ventricular longitudinal strain, right ventricular diastolic longitudinal strain rate (RV DLSR), right ventricular diastolic circumferential strain rate, and right ventricular longitudinal displacement were significantly impaired (P < 0.05). The content of miR-149-3p in the lung tissue of the model group was dramatically inferior to that of the control group and the interference group (P < 0.05). The contents of Wnt1, β-catenin, RhoA, and Wnt5a in the lung tissue of the model group were dramatically superior to those of the control group (P < 0.05). In addition, the expressions of TNF-α, IL-1β, IL-6, and NF-kB in the alveolar lavage fluid of the model group were statistically different from those of control group (P < 0.05). The expression levels of SP-D and surfactant protein A (SP-A) in the COPD group were also statistically different from those of control group (P < 0.05).

Conclusion

miR-149-3p regulated the expression of Wnt1, β-catenin, RhoA, and Wnt5a, which also affected the signal transmission of the Wnt pathway, causing changes in the expression of alveolar inflammatory factors. Eventually, it affected the development of COPD.

Contribution of Host miRNA-223-3p to SARS-CoV-Induced Lung Inflammatory Pathology

Severe acute respiratory syndrome coronavirus (SARS-CoV) and the closely related SARS-CoV-2 are emergent highly pathogenic human respiratory viruses causing acute lethal disease associated with lung damage and dysregulated inflammatory responses. SARS-CoV envelope protein (E) is a virulence factor involved in the activation of various inflammatory pathways. Here, we study the contribution of host miRNAs to the virulence mediated by E protein. Small RNAseq analysis of infected mouse lungs identified miRNA-223 as a potential regulator of pulmonary inflammation, since it was significantly increased in SARS-CoV-WT virulent infection compared to the attenuated SARS-CoV-ΔE infection. In vivo inhibition of miRNA-223-3p increased mRNA levels of pro-inflammatory cytokines and NLRP3 inflammasome, suggesting that during lung infection, miRNA-223 might contribute to restrict an excessive inflammatory response. Interestingly, miRNA-223-3p inhibition also increased the levels of the CFTR transporter, which is involved in edema resolution and was significantly downregulated in the lungs of mice infected with the virulent SARS-CoV-WT virus. At the histopathological level, a decrease in the pulmonary edema was observed when miR-223-3p was inhibited, suggesting that miRNA-223-3p was involved in the regulation of the SARS-CoV-induced inflammatory pathology. These results indicate that miRNA-223 participates in the regulation of E protein-mediated inflammatory response during SARS-CoV infection by targeting different host mRNAs involved in the pulmonary inflammation, and identify miRNA-223 as a potential therapeutic target in SARS-CoV infection.

CTNNAL1 participates in the regulation of mucus overproduction in HDM‐induced asthma mouse model through the YAP‐ROCK2 pathway

Our previous study indicated that adhesion molecule catenin alpha‐like 1(CTNNAL1) is downregulated in airway epithelial cells of asthma patients and asthma animal model but little is known about how the CTNNAL1 affects asthma pathogenesis. To reveal the direct relationship between asthma and CTNNAL1, CTNNAL1‐deficient mouse model in bronchopulmonary tissue was constructed by introducing CTNNAL1‐siRNA sequence using adeno‐associated virus (AAV) as vector. The mouse model of asthma was established by stimulation of house dust mite (HDM). After HDM‐challenged, there was marked airway inflammation, especially mucus hypersecretion in the CTNNAL1‐deficient mice. In addition, the CTNNAL1‐deficient mice exhibited an increase of lung IL‐4 and IL‐13 levels, as well as a significant increase of goblet cell hyperplasia and MUC5AC after HDM exposure. The expression of Yes‐associated protein (YAP), protein that interacted with α‐catenin, was downregulated after CTNNAL1 silencing and was upregulated due to its overexpression. In addition, the interaction between CTNNAL1 and YAP was confirmed by CO‐IP. Besides, inhibition of YAP could decrease the secretion of MUC5AC, IL‐4 and IL‐13 in CTNNAL1‐deficient 16HBE14o‐cells. Above results indicated us that CTNNAL1 regulated mucus hypersecretion through YAP pathway. In addition, the expression of ROCK2 increased when CTNNAL1 was silenced and decreased after YAP silencing, and inhibition of YAP decreased the expression of ROCK2 in CTNNAL1‐deficient HBE cells. Inhibition of ROCK2 decreased MUC5AC expression and IL‐13 secretion. In all, our study demonstrates that CTNNAL1 plays an important role in HDM‐induced asthma, mediating mucus secretion through the YAP‐ROCK2 pathway.

LncRNA RP5-857K21.7 inhibits PDGF-BB-induced proliferation and migration of airway smooth muscle cells through the miR-508-3p/PI3K/AKT/mTOR axis

The continuous increase in the prevalence of asthma poses a threat to human health. Despites numerous researches, the understanding of asthma development still remain elusive, hindering the development of effective treatment. Here, we explored the role of lncRNA RP5-857K21.7 (RP5-857K21.7) in the development of asthma and its potential molecular mechanism of regulation. Airway smooth muscle cells (ASMCs) were isolated and cultured after which some of the cells were induced with PDGF-BB to build an asthma cell model, and then, qRT-PCR analysis was used to measure the expression level of RP5-857K21.7 in the cell model. Result shows that the RP5-857K21.7 is significantly downregulated in PDGF-BB-induced ASMCs cells. Through CCK-8, transwell, and flow cytometry assay, we examined the functional impact of RP5-857K21.7 on the proliferation, migration, and apoptosis of the ASMCs, respectively, and found that the overexpression of RP5-857K21.7 markedly inhibit PDGF-BB-induced ASMCs cell proliferation, migration and induce apoptosis. Bioinformatics analysis predicted that the RP5-857K21.7 could sponge miR-508-3p and result was validated through a dual-luciferase reporter assay, biotinylated RNA pull-down assay, and RIP-qRT-PCR analysis. Mechanistically, RP5-857K21.7 regulates the PI3K/AKT/mTOR pathway by endogenously sponging miR-508-3p to inhibit PDGF-BB-induced ASMCs cell proliferation, migration and induce apoptosis. The current research suggests that the RP5-857K21.7 and its associated molecular pathway (miR-508-3p/PI3K/AKT/mTOR axis) might be a useful therapeutic target for the treatment of asthma disease.

An update on the roles of immune system-derived microRNAs in cardiovascular diseases

Cardiovascular diseases (CVD) are a leading cause of human death worldwide. Over the past two decades, the emerging field of cardioimmunology has demonstrated how cells of the immune system play vital roles in the pathogenesis of CVD. MicroRNAs (miRNAs) are critical regulators of cellular identity and function. Cell-intrinsic, as well as cell-extrinsic, roles of immune and inflammatory cell-derived miRNAs have been, and continue to be, extensively studied. Several 'immuno-miRNAs' appear to be specifically expressed or demonstrate greatly enriched expression within leucocytes. Identification of miRNAs as critical regulators of immune system signalling pathways has posed the question of whether and how targeting these molecules therapeutically, may afford opportunities for disease treatment and/or management. As the field of cardioimmunology rapidly continues to advance, this review discusses findings from recent human and murine studies which contribute to our understanding of how leucocytes of innate and adaptive immunity are regulated-and may also regulate other cell types, via the actions of the miRNAs they express, in the context of CVD. Finally, we focus on available information regarding miRNA regulation of regulatory T cells and argue that targeted manipulation of miRNA regulated pathways in these cells may hold therapeutic promise for the treatment of CVD and associated risk factors.

Regulatory roles of miRNAs 16, 133a, and 223 on osteoclastic bone destruction caused by breast cancer metastasis

Osteolytic bone metastasis leads to skeletal-related events, resulting in a decline in the patient activities and survival; therefore, it is important to understand the mechanism underlying bone metastasis. Recent studies have suggested that microRNAs (miRNAs or miRs) are involved in osteoclast differentiation and/or osteolytic bone metastasis; however, the roles of miRNAs have not been elucidated. In the present study, the roles of miRNAs in bone destruction caused by breast cancer metastasis were investigated in vitro and in vivo. miR-16, miR-133a and miR-223 were transfected into a human breast cancer cell line, MDA-MB-231. The expression of osteolytic factors in conditioned medium (miR-CM) collected from the culture of transfected cells was assessed. To evaluate the effects of miRNAs on osteoclast differentiation and activities, tartrate-resistant acid phosphatase (TRAP) staining and bone resorptive assays were performed in osteoclasts following miR-CM treatment. To create in vivo bone metastasis models for histological and morphometric evaluation, miRNA-transfected MDA-MB-231 cells were transplanted into the proximal tibia of nude mice. Expression of osteolytic factors, including receptor activator for nuclear factor-κB ligand (RANKL), interleukin (IL)-1β, IL-6, parathyroid hormone-related protein (PTHrP), and tumor necrosis factor (TNF), was increased in miR-16-CM, whereas it was decreased in both miR-133a-CM and miR-223-CM. TRAP staining and bone resorptive assays revealed that osteoclast function and activities were promoted by miR-16-CM treatment, whereas they were suppressed by miR-133a-CM and miR-223-CM. Consistent with in vitro findings, in vivo experiments revealed that the overexpression of miR-16 increased osteoclast activities and bone destruction in MDA-MB-231 cells, whereas the opposite results were observed in both miR-133a- and miR-223-transfected MDA-MB-231 cells. Our results indicated that miR-16 promoted osteoclast activities and bone destruction caused by breast cancer metastasis in the bone microenvironment, whereas miR-133a and miR-223 suppressed them. These miRNAs could be potential biomarkers and therapeutic targets for breast cancer bone metastasis.

Extracellular Vesicles in Airway Homeostasis and Pathophysiology

The epithelial–mesenchymal trophic unit (EMTU) is a morphofunctional entity involved in the maintenance of the homeostasis of airways as well as in the pathogenesis of several diseases, including asthma and chronic obstructive pulmonary disease (COPD). The “muco-microbiotic layer” (MML) is the innermost layer of airways made by microbiota elements (bacteria, viruses, archaea and fungi) and the surrounding mucous matrix. The MML homeostasis is also crucial for maintaining the healthy status of organs and its alteration is at the basis of airway disorders. Nanovesicles produced by EMTU and MML elements are probably the most important tool of communication among the different cell types, including inflammatory ones. How nanovesicles produced by EMTU and MML may affect the airway integrity, leading to the onset of asthma and COPD, as well as their putative use in therapy will be discussed here.

MiR-223 is increased in lungs of patients with COPD and modulates cigarette smoke-induced pulmonary inflammation

Since microRNA (miR)-223-3p modulates inflammatory responses and COPD is associated with amplified pulmonary inflammation, we hypothesized that miR-223-3p plays a role in COPD pathogenesis. Expression of miR-223-3p was measured in lung tissue of 2 independent cohorts with COPD GOLD stage II-IV patients, never smokers and smokers without COPD. The functional role of miR-223-3p was studied in deficient mice and upon overexpression in airway epithelial cells from COPD and controls. We observed higher miR-223-3p levels in patients with COPD stage II-IV compared to (non)-smoking controls, and levels were associated with higher neutrophil numbers in bronchial biopsies of COPD patients. MiR-223-3p expression was also increased in lungs and bronchoalveolar lavage of cigarette smoke (CS)-exposed mice. CS-induced neutrophil and monocyte lung infiltration was stronger in miR-223 deficient mice upon acute (5 days) exposure, but attenuated upon sub-chronic (4 weeks) exposure. Additionally, miR-223 deficiency attenuated acute and sub-chronic CS-induced lung infiltration of dendritic cells and T lymphocytes. Finally, in vitro overexpression of miR-223-3p in non-COPD airway epithelial cells suppressed CXCL8 and GM-CSF secretion and gene expression of the pro-inflammatory transcription factor TRAF6. Importantly, this suppressive effect of miR-223-3p was compromised in COPD-derived cultures. In conclusion, we demonstrate that miR-223-3p is increased in lungs of COPD patients and CS-exposed mice, and is associated with neutrophilic inflammation. In vivo data indicate that miR-223 acts as negative regulator of acute CS-induced neutrophilic and monocytic inflammation. In vitro data suggests that miR-223-3p does so by suppressing pro-inflammatory airway epithelial responses, which is less effective in COPD epithelium.

miRNA-223 as a regulator of inflammation and NLRP3 inflammasome, the main fragments in the puzzle of immunopathogenesis of different inflammatory diseases and COVID-19

Millions of people around the world are involved with COVID-19 due to infection with SARS-CoV-2. Virological features of SARS-CoV-2, including its genomic sequence, have been identified but the mechanisms governing COVID-19 immunopathogenesis have remained uncertain. miR-223 is a hematopoietic cell-derived miRNA that is implicated in regulating monocyte-macrophage differentiation, neutrophil recruitment, and pro-inflammatory responses. The miR-223 controls inflammation by targeting a variety of factors, including TRAF6, IKKα, HSP-70, FOXO1, TLR4, PI3K/AKT, PARP-1, HDAC2, ITGB3, CXCL2, CCL3, IL-6, IFN-I, STMN1, IL-1β, IL-18, Caspase-1, NF-κB, and NLRP3. The key role of miR-223 in regulating the inflammatory process and its antioxidant and antiviral role can suggest this miRNA as a potential regulatory factor in the process of COVID-19 immunopathogenesis.

Role of MicroRNA in Inflammatory Bowel Disease: Clinical Evidence and the Development of Preclinical Animal Models

The dysregulation of microRNA (miRNA) is implicated in cancer, inflammation, cardiovascular disorders, drug resistance, and aging. While most researchers study miRNA's role as a biomarker, for example, to distinguish between various sub-forms or stages of a given disease of interest, research is also ongoing to utilize these small nucleic acids as therapeutics. An example of a common pleiotropic disease that could benefit from miRNA-based therapeutics is inflammatory bowel disease (IBD), which is characterized by chronic inflammation of the small and large intestines. Due to complex interactions between multiple factors in the etiology of IBD, development of therapies that effectively maintain remission for this disease is a significant challenge. In this review, we discuss the role of dysregulated miRNA expression in the context of clinical ulcerative colitis (UC) and Crohn's disease (CD)-the two main forms of IBD-and the various preclinical mouse models of IBD utilized to validate the therapeutic potential of targeting these miRNA. Additionally, we highlight advances in the development of genetically engineered animal models that recapitulate clinical miRNA expression and provide powerful preclinical models to assess the diagnostic and therapeutic promise of miRNA in IBD.

Identification of asthma associated microRNAs in bronchial biopsies

Changes in microRNA (miRNA) expression can contribute to the pathogenesis of many diseases, including asthma. We aimed to identify miRNAs that are differentially expressed between asthma patients and healthy controls and explored their association with clinical and inflammatory parameters of asthma.Differentially expressed miRNAs were determined by small RNA sequencing on bronchial biopsies of 79 asthma patients and 82 healthy controls using linear regression models. Differentially expressed miRNAs were associated with clinical and inflammatory asthma features. Potential miRNA-mRNA interactions were analysed using mRNA data available from the same bronchial biopsies and enrichment of pathways was identified with Enrichr and g:Profiler.In total 78 differentially expressed miRNAs were identified in bronchial biopsies of asthma patients compared to controls, of which 60 remained differentially expressed after controlling for smoke and inhaled corticosteroid treatment. We identified several asthma associated miRNAs, including miR-125b-5p and miR-223-3p, based on a significant association with multiple clinical and inflammatory asthma features and their negative correlation with genes associated with the presence of asthma. The most enriched biological pathway(s) affected by miR-125b-5p and miR-223-3p were inflammatory response and cilium assembly and organisation. Of interest, we identified that lower expression of miR-26a-5p was linked to more severe eosinophilic inflammation as measured in blood, sputum as well as bronchial biopsies. Collectively, we identified miR-125b-5p, miR-223-3p and miR-26a-5p, as potential regulators that could contribute to the pathogenesis of asthma.

Anti-inflammatory effects of microRNA-223 on sepsis-induced lung injury in rats by targeting the Toll-like receptor signaling pathway

The aim of the present study was to investigate the mediation of micro RNA (miR)-223 on the anti-inflammatory effect of the Toll-like receptor (TLR) signaling pathway on sepsis-induced lung injury in rats via negatively regulating the expression of interleukin (IL)-6. Sprague-Dawley rats were used in the present study. It was determined whether miR-223 is differentially expressed in the lung using reverse transcription-quantitative PCR techniques and the content of cytokines in bronchoalveolar lavage (BAL) fluid was detected. The protein expression levels of TLR4 and nuclear factor (NF)-κB p65 were examined by western blotting and the pathological changes in the lung tissues of the sepsis group were observed. Hematoxylin and eosin was used to stain the lung tissues. The alveoli in the sham group exhibited a normal structure and morphology. In the sepsis group, the alveoli of the lung tissues were surrounded by numerous neutrophils, the mesenchyme was swollen, regions of the alveolar wall exhibited fibrosis and the alveolar wall was thickened. Furthermore, in the sepsis group, miR-223 expression was increased in the lung tissues when compared with that in the sham group. The content of cytokines, IL-6 and IL-1β in the BAL fluid was significantly increased when compared with that of the sham group and TLR4 and NF-κB were also highly expressed. In addition, when compared with RAW264.7 cells that were overexpressing miR-223, the content of IL-6 and IL-1β in the supernatant and protein expression of TLR and NF-κB in cells were markedly decreased. Thus, it was demonstrated that miR-223 negatively regulated the expression of IL-6, mediating the TLR4/NF-κB signaling pathway and exerting an anti-inflammatory effect in sepsis-induced lung injury.

Down-regulated gga-miR-223 inhibits proliferation and induces apoptosis of MG-infected DF-1 cells by targeting FOXO3

Mycoplasma gallisepticum (MG) is a major poultry pathogen that can induce Chronic Respiratory Disease (CRD) in chickens, causing serious economic losses in the poultry industry worldwide. Increasing evidence suggests that microRNAs (miRNAs) act as a vital role in resisting microbial pathogenesis and maintaining cellular mechanism. Our previous miRNAs sequencing data showed that gga-miR-223 expression level significantly decreased in MG-infected chicken lungs. The aim of this study was to reveal the role of gga-miR-223 in MG-induced CRD progression. We found that gga-miR-223 was remarkably down regulated and forkhead box O3 (FOXO3) was up-regulated in both MG-infected chicken embryos lungs and the chicken embryonic fibroblast cell line (DF-1) by qPCR. FOXO3 was verified as the target gene of gga-miR-223 through bioinformatics analysis and dual-luciferase reporter assay. Further studies showed that overexpressed gga-miR-223 could promote cell proliferation, cell cycle, and inhibit cell apoptosis by notably promoting the expression of cell cycle marker genes cyclin-dependent kinase 1 (CDK1), cyclin-dependent kinase 6 (CDK6) and Cyclin D1 (CCND1) and inhibiting the expression of apoptosis markers Bcl-2-like 11(BIM), FAS ligand (FASLG) and TNF-related apoptosis-inducing ligand (TRAIL). As expected, FOXO3 knockdown group got similar results. Overexpression of gga-miR-223 observably promoted cell multiplication, cell cycle progression, and inhibited apoptosis of MG-infected DF-1 cells, while inhibited gga-miR-223 had the opposite effect. Taken together, upon MG-infection, downregulated gga-miR-223 could decrease proliferation, cycle progression, and increase apoptosis through directly targeting FOXO3 to exert an aggravating MG-infectious effect.

Epigenetics and expression of key genes associated with cardiac fibrosis: NLRP3, MMP2, MMP9, CCN2/CTGF and AGT

Aims:

Excessive inflammatory signaling and pathological remodeling of the extracellular matrix drive cardiac fibrosis and require changes in gene expression.

Materials and methods:

Using bioinformatics, both tissue-specific expression profiles and epigenomic profiles of some genes critical for cardiac fibrosis were examined, namely, NLRP3, MMP2, MMP9, CCN2/CTGF, AGT (encodes angiotensin II precursors) and hsa-mir-223 (post-transcriptionally regulates NLRP3).

Results:

In monocytes, neutrophils, fibroblasts, venous cells, liver and brain, enhancers or super-enhancers were found that correlate with high expression of these genes. One enhancer extended into a silent gene neighbor. These enhancers harbored tissue-specific foci of DNA hypomethylation, open chromatin and transcription factor binding.

Conclusions:

This study identified previously undescribed enhancers containing hypomethylated transcription factor binding subregions that are predicted to regulate expression of these cardiac fibrosis-inducing genes.

LINC00987 Ameliorates COPD by Regulating LPS-Induced Cell Apoptosis, Oxidative Stress, Inflammation and Autophagy Through Let-7b-5p/SIRT1 Axis

Background

Chronic obstructive pulmonary disease (COPD) is the third cause of disease-related death and brings a heavy burden to human health. Long non-coding RNA (lncRNA) was revealed to participate in COPD pathogenesis. This study aims to establish the effects and regulatory mechanism of lncRNA long intergenic non-coding 00987 (LINC00987) in lipopolysaccharide (LPS)-induced apoptosis, oxidative stress, inflammation and autophagy in BEAS-2B cells.

Methods

The expression levels of LINC00987 and let-7b-5p were detected by real-time quantitativepolymerase chain reaction (RT-qPCR). The expression of apoptosis-associated proteins, oxidative stress (ROS)-related proteins, autophagy-related proteins and sirtuin1 (SIRT1) protein was determined by Western blot. Cell viability was illustrated by cell counting kit-8 (CCK-8) assay. Cell apoptosis was investigated by caspase3 activity and apoptosis analysis assays. ROS, inflammation and autophagy were demonstrated by detecting reactive ROS level and superoxide dismutase (SOD) activity, enzyme-linked immunosorbent assay (ELISA) and Western blot analysis, respectively. The binding sites between let-7b-5p and LINC00987 or SIRT1 were predicted by lncBase or miRWalk online database, and identified by dual-luciferase reporter assay.

Results

LINC00987 expression was strikingly downregulated and let-7b-5p expression was obviously upregulated in COPD tissues and LPS-induced BEAS-2B cells compared with control groups. LINC00987 overexpression promoted BEAS-2B cells against LPS-mediated viability, apoptosis, oxidative stress, inflammation and autophagy, whereas these effects were attenuated by let-7b-5p mimic or SIRT1 knockdown. Furthermore, LINC00987 sponged let-7b-5p and let-7b-5p bound to SIRT1.

Conclusion

LINC00987 ameliorated COPD through modulating LPS-induced cell apoptosis, oxidative stress, inflammation and autophagy via sponging let-7b-5p to associate with SIRT1. This finding will provide a theoretical basis for the research of LncRNA-mediated treatment in COPD.

Targeting neutrophils in asthma: A therapeutic opportunity?

Suppression of airway inflammation with inhaled corticosteroids has been the key therapeutic approach for asthma for many years. Identification of inflammatory phenotypes in asthma has moreover led to important breakthroughs, e.g. with specific targeting of the IL-5 pathway as add-on treatment in difficult-to-treat eosinophilic asthma. However, the impact of interfering with the neutrophilic component in asthma is less documented and understood. This review provides an overview of established and recent insights with regard to the role of neutrophils in asthma, focusing on research in humans. We will describe the main drivers of neutrophilic responses in asthma, the heterogeneity in neutrophils and how they could contribute to asthma pathogenesis. Moreover we will describe findings from clinical trials, in which neutrophilic inflammation was targeted. It is clear that neutrophils are important actors in asthma development and play a role in exacerbations. However, more research is required to fully understand how modulation of neutrophil activity could lead to a significant benefit in asthma patients with airway neutrophilia.