The Clinical Significance of Changes in the Expression Levels of MicroRNA-1 and Inflammatory Factors in the Peripheral Blood of Children with Acute-Stage Asthma

Regulation of ferroptosis in osteoarthritis and osteoarthritic chondrocytes by typical MicroRNAs in chondrocytes

Osteoarthritis (OA) is a progressive degenerative disorder impacting bones and joints, worsened by chronic inflammation, immune dysregulation, mechanical stress, metabolic disturbances, and various other contributing factors. The complex interplay of cartilage damage, loss, and impaired repair mechanisms remains a critical and formidable aspect of OA pathogenesis. At the genetic level, multiple genes have been implicated in the modulation of chondrocyte metabolism, displaying both promotive and inhibitory roles. Recent research has increasingly focused on the influence of non-coding RNAs in the regulation of distinct cell types within bone tissue in OA. In particular, an expanding body of evidence highlights the regulatory roles of microRNAs in OA chondrocytes. This review aims to consolidate the most relevant microRNAs associated with OA chondrocytes, as identified in recent studies, and to elucidate their involvement in chondrocyte metabolic processes and ferroptosis. Furthermore, this study explores the complex regulatory interactions between long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) in OA, with an emphasis on microRNA-mediated mechanisms. Finally, critical gaps in the current research are identified, offering strategic insights to advance the understanding of OA pathophysiology and guide therapeutic developments in this field.

MicroRNAs in chronic pediatric diseases (Review)

MicroRNAs are small non-coding RNAs with a length of 20-24 nucleotides. They bind to the 3'-untranslated region of target genes to induce the degradation of target mRNAs or inhibit their translation. Therefore, they are involved in the regulation of development, apoptosis, proliferation, differentiation and other biological processes (including hormone secretion, signaling and viral infections). Chronic diseases in children may be difficult to treat and are often associated with malnutrition resulting from a poor diet. Consequently, further complications, disease aggravation and increased treatment costs impose a burden on patients and their families. Existing evidence suggests that microRNAs are involved in various chronic non-neoplastic diseases in children. The present review discusses the roles of microRNAs in five major chronic diseases in children, namely, diabetes mellitus, congenital heart diseases, liver diseases, bronchial asthma and epilepsy, providing a theoretical basis for them to become therapeutic biomarkers in chronic pediatric diseases.

Dermatophagoides farinae microRNAs released to external environments via exosomes regulate inflammation-related gene expression in human bronchial epithelial cells

Background

Dermatophagoides farinae (DFA) is an important species of house dust mites (HDMs) that causes allergic diseases. Previous studies have focused on allergens with protein components to explain the allergic effect of HDMs; however, there is little knowledge on the role of microRNAs (miRNAs) in the allergic effect of HDMs. This study aimed to unravel the new mechanism of dust mite sensitization from the perspective of cross-species transport of extracellular vesicles-encapsulated miRNAs from HDMs.

Methods

Small RNA (sRNA) sequencing was performed to detect miRNAs expression profiles from DFA, DFA-derived exosomes and DFA culture supernatants. A quantitative fluorescent real-time PCR (qPCR) assay was used to detect miRNAs expression in dust specimens. BEAS-2B cells endocytosed exosomes were modeled in vitro to detect miRNAs from DFA and the expression of related inflammatory factors. Representative dfa-miR-276-3p and dfa-novel-miR2 were transfected into BEAS-2B cells, and then differentially expressed genes (DEGs) were analyzed by RNA sequencing. Protein-protein interaction (PPI) network analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment analyses were performed on the first 300 nodes of DEGs.

Results

sRNA sequencing identified 42 conserved miRNAs and 66 novel miRNAs in DFA, DFA-derived exosomes, and DFA culture supernatants. A homology analysis was performed on the top 18 conserved miRNAs with high expression levels. The presence of dust mites and miRNAs from HDMs in living environment were also validated. Following uptake of DFA-derived exosomes by BEAS-2B cells, exosomes transported miRNAs from DFA to target cells and produced pro-inflammatory effects in corresponding cells. RNA sequencing identified DEGs in dfa-miR-276-3p and dfa-novel-miR2 transfected BEAS-2B cells. GO and KEGG enrichment analyses revealed the role of exosomes with cross-species transporting of DFA miRNAs in inflammatory signaling pathways, such as JAK-STAT signaling pathway, PI3K/AKT signaling pathway and IL-6-mediated signaling pathway.

Conclusion

Our findings demonstrate the miRNAs expression profiles in DFA for the first time. The DFA miRNAs are delivered into living environments via exosomes, and engulfed by human bronchial epithelial cells, and cross-species regulation may contribute to inflammation-related processes.

Air Pollution: Role of Extracellular Vesicles-Derived Non-Coding RNAs in Environmental Stress Response

Air pollution has increased over the years, causing a negative impact on society due to the many health-related problems it can contribute to. Although the type and extent of air pollutants are known, the molecular mechanisms underlying the induction of negative effects on the human body remain unclear. Emerging evidence suggests the crucial involvement of different molecular mediators in inflammation and oxidative stress in air pollution-induced disorders. Among these, non-coding RNAs (ncRNAs) carried by extracellular vesicles (EVs) may play an essential role in gene regulation of the cell stress response in pollutant-induced multiorgan disorders. This review highlights EV-transported ncRNAs' roles in physiological and pathological conditions, such as the development of cancer and respiratory, neurodegenerative, and cardiovascular diseases following exposure to various environmental stressors.

Asthma Exacerbations: The Genes Behind the Scenes

The clinical and socioeconomic burden of asthma exacerbations (AEs) constitutes a major public health problem. In the last 4 years, there has been an increase in ethnic diversity in candidate-gene and genome-wide association studies of AEs, which in the latter case led to the identification of novel genes and underlying pathobiological processes. Pharmacogenomics, admixture mapping analyses, and the combination of multiple "omics" layers have helped to prioritize genomic regions of interest and/or facilitated our understanding of the functional consequences of genetic variation. Nevertheless, the field still lags behind the genomics of asthma, where a vast compendium of genetic approaches has been used (eg, gene-environment nteractions, next-generation sequencing, and polygenic risk scores). Furthermore, the roles of the DNA methylome and histone modifications in AEs have received little attention, and microRNA findings remain to be validated in independent studies. Likewise, the most recent transcriptomic studies highlight the importance of the host-airway microbiome interaction in the modulation of risk of AEs. Leveraging -omics and deep-phenotyping data from subtypes or homogenous subgroups of patients will be crucial if we are to overcome the inherent heterogeneity of AEs, boost the identification of potential therapeutic targets, and implement precision medicine approaches to AEs in clinical practice.

Integrated Network Pharmacology and Gut Microbiota Analysis to Explore the Mechanism of Sijunzi Decoction Involved in Alleviating Airway Inflammation in a Mouse Model of Asthma

Background

Asthma is a chronic inflammatory disease of the airways with recurrent attacks, which seriously affects the patients' quality of life and even threatens their lives. The disease can even threaten the lives of patients. Sijunzi decoction (SJZD), a classical Chinese medicine formula with a long history of administration, is a basic formula used for the treatment of asthma and demonstrates remarkable efficacy. However, the underlying mechanism has not been elucidated.

Materials and Methods

We aimed to integrate network pharmacology and intestinal flora sequencing analysis to study the mechanism of SJZD in the treatment of allergic asthmatic mice. The active compounds of SJZD and their asthma-related targets were predicted by various databases. We performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to identify potentially relevant pathways for target genes. Furthermore, the active compound-target and target-signaling pathway network maps were constructed by using Cytoscape 3.8.2. These results were combined with those of the intestinal flora sequencing analysis to study the influence of SJZD on airway inflammation in allergic asthmatic mice.

Result

We obtained 137 active compounds from SJZD and associated them with 1445 asthma-related targets acquired from the databases. A total of 109 common targets were identified. We visualized active compound-target and target-signaling pathway network maps. The pathological analysis and inflammation score results suggested that SJZD could alleviate airway inflammation in asthmatic mice. Sequencing analysis of intestinal flora showed that SJZD could increase the relevant abundance of beneficial bacterial genus and maintain the balance of the intestinal flora. The core toll-like receptor (TLR) signaling pathway was identified based on network pharmacology analysis, and the important role TLRs play in intestinal flora and organismal immunity was also recognized. The analysis of the correlation between environmental factors and intestinal flora revealed that beneficial bacterial genera were negatively correlated with TLR2 and positively correlated with the TLR7 expression. Furthermore, they were positively correlated with IFN-γ and IL-10 levels and negatively correlated with IL-4 and IL-17 levels.

Conclusion

SJZD alleviated the airway inflammation state in asthmatic mice. The findings suggest that increasing the relevant abundance of beneficial intestinal bacteria in mice with asthma, regulating intestinal flora, interfering with the level of TLR2 and TLR7 expression to adjust the secretion of inflammatory factors, and alleviating asthmatic airway inflammation may be the possible mechanism involved in the treatment of asthma by SJZD, providing a basis for further studies on SJZD.

Epigenetic regulation of immune function in asthma

Asthma is a common complex respiratory disease characterized by chronic airway inflammation and partially reversible airflow obstruction resulting from genetic and environmental determinants. Because epigenetic marks influence gene expression and can be modified by both environmental exposures and genetic variation, they are increasingly recognized as relevant to the pathogenesis of asthma and may be a key link between environmental exposures and asthma susceptibility. Unlike changes to DNA sequence, epigenetic signatures are dynamic and reversible, creating an opportunity for not only therapeutic targets but may serve as biomarkers to follow disease course and identify molecular subtypes in heterogeneous diseases such as asthma. In this review, we will examine the relationship between asthma and 3 key epigenetic processes that modify gene expression: DNA methylation, modification of histone tails, and noncoding RNAs. In addition to presenting a comprehensive assessment of the existing epigenetic studies focusing on immune regulation in asthma, we will discuss future directions for epigenetic investigation in allergic airway disease.

MicroRNAs: A Promising Tool for Asthma Diagnosis and Severity Assessment. A Systematic Review

Micro RNAs (miRNAs) are short, non-coding RNAs (Ribonucleic acids) with regulatory functions that could prove useful as biomarkers for asthma diagnosis and asthma severity-risk stratification. The objective of this systematic review is to identify panels of miRNAs that can be used to support asthma diagnosis and severity-risk assessment. Three databases (Medline, Embase, and SCOPUS) were searched up to 15 September 2020 to identify studies reporting differential expression of specific miRNAs in the tissues of adults and children with asthma. Studies reporting miRNAs associations in animal models that were also studied in humans were included in this review. We identified 75 studies that met our search criteria. Of these, 66 studies reported more than 200 miRNAs that are differentially expressed in asthma patients when compared to non-asthmatic controls. In addition, 16 studies reported 17 miRNAs that are differentially expressed with differences in asthma severity. We were able to construct two panels of miRNAs that are expressed in blood and can serve as core panels to further investigate the practicality and efficiency of using miRNAs as non-invasive biomarkers for asthma diagnosis and severity-risk assessment, respectively.

Emerging Roles of Non-Coding RNAs in Childhood Asthma

Asthma is a chronic airway inflammatory disease in children characterized by airway inflammation, airway hyperresponsiveness and airway remodeling. Childhood asthma is usually associated with allergy and atopy, unlike adult asthma, which is commonly associated with obesity, smoking, etc. The pathogenesis and diagnosis of childhood asthma also remains more challenging than adult asthma, such as many diseases showing similar symptoms may coexist and be confused with asthma. In terms of the treatment, although most childhood asthma can potentially be self-managed and controlled with drugs, approximately 5-10% of children suffer from severe uncontrolled asthma, which carries significant health and socioeconomic burdens. Therefore, it is necessary to explore the pathogenesis of childhood asthma from a new perspective. Studies have revealed that non-coding RNAs (ncRNAs) are involved in the regulation of respiratory diseases. In addition, altered expression of ncRNAs in blood, and in condensate of sputum or exhalation affects the progression of asthma via regulating immune response. In this review, we outline the regulation and pathogenesis of asthma and summarize the role of ncRNAs in childhood asthma. We also hold promise that ncRNAs may be used for the development of biomarkers and support a new therapeutic strategy for childhood asthma.

Emerging Advances of Non-coding RNAs and Competitive Endogenous RNA Regulatory Networks in Asthma

Asthma is a chronic inflammatory disease characterized by airway remodeling and bronchial hyperresponsiveness. A variety of effector cells and cytokines jointly stimulate the occurrence of inflammatory response in asthma. Although the pathogenesis of asthma is not entirely clear, the possible roles of non-coding RNAs (ncRNAs) have been recently demonstrated. NcRNAs are non-protein-coding RNA molecules, such as circular RNAs (circRNAs), long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), which are involved in the regulation of a variety of biological processes. Mounting studies have shown that ncRNAs play pivotal roles in the occurrence and progression of asthma via competing endogenous RNA (ceRNA) regulatory networks. However, the specific mechanism and clinical application of ncRNAs and ceRNA regulatory networks in asthma have not been fully elucidated, which are worthy of further investigation. This paper comprehensively summarized the current progress on the roles of miRNAs, lncRNAs, circRNAs, and ceRNA regulatory networks in asthma, which can provide a better understanding for the disease pathogenesis and is helpful for identifying novel biomarkers for asthma.

Recent Insights into the Management of Inflammation in Asthma

The present prevailing inflammatory paradigm in asthma is of T2-high inflammation orchestrated by key inflammatory cells like Type 2 helper lymphocytes, innate lymphoid cells group 2 and associated cytokines. Eosinophils are key components of this T2 inflammatory pathway and have become key therapeutic targets. Real-world evidence on the predominant T2-high nature of severe asthma is emerging. Various inflammatory biomarkers have been adopted in clinical practice to aid asthma characterization including airway measures such as bronchoscopic biopsy and lavage, induced sputum analysis, and fractional exhaled nitric oxide. Blood measures like eosinophil counts have also gained widespread usage and multicomponent algorithms combining different parameters are now appearing. There is also growing interest in potential future biomarkers including exhaled volatile organic compounds, micro RNAs and urinary biomarkers. Additionally, there is a growing realisation that asthma is a heterogeneous state with numerous phenotypes and associated treatable traits. These may show particular inflammatory patterns and merit-specific management approaches that could improve asthma patient outcomes. Inhaled corticosteroids (ICS) remain the mainstay of asthma management but their use earlier in the course of disease is being advocated. Recent evidence suggests potential roles for ICS in combination with long-acting beta-agonists (LABA) for as needed use in mild asthma whilst maintenance and reliever therapy regimes have gained widespread acceptance. Other anti-inflammatory strategies including ultra-fine particle ICS, leukotriene receptor antagonists and macrolide antibiotics may show efficacy in particular phenotypes too. Monoclonal antibody biologic therapies have recently entered clinical practice with significant impacts on asthma outcomes. Understanding of the efficacy and use of those agents is becoming clearer with a growing body of real-world evidence as is their potential applicability to other treatable comorbid traits. In conclusion, the evolving understanding of T2 driven inflammation alongside a treatable traits disease model is enhancing therapeutic approaches to address inflammation in asthma.

The Predictive Role of Biomarkers and Genetics in Childhood Asthma Exacerbations

Asthma exacerbations are associated with significant childhood morbidity and mortality. Recurrent asthma attacks contribute to progressive loss of lung function and can sometimes be fatal or near-fatal, even in mild asthma. Exacerbation prevention becomes a primary target in the management of all asthmatic patients. Our work reviews current advances on exacerbation predictive factors, focusing on the role of non-invasive biomarkers and genetics in order to identify subjects at higher risk of asthma attacks. Easy-to-perform tests are necessary in children; therefore, interest has increased on samples like exhaled breath condensate, urine and saliva. The variability of biomarker levels suggests the use of seriate measurements and composite markers. Genetic predisposition to childhood asthma onset has been largely investigated. Recent studies highlighted the influence of single nucleotide polymorphisms even on exacerbation susceptibility, through involvement of both intrinsic mechanisms and gene-environment interaction. The role of molecular and genetic aspects in exacerbation prediction supports an individual-shaped approach, in which follow-up planning and therapy optimization take into account not only the severity degree, but also the risk of recurrent exacerbations. Further efforts should be made to improve and validate the application of biomarkers and genomics in clinical settings.

MicroRNAs: future biomarkers and targets of therapy in asthma?

PURPOSE OF REVIEW

MicroRNAs (miRNAs) are small noncoding RNA molecules that are considered one of the fundamental regulatory mechanisms of gene expression. They are involved in many biologic processes, such as signal transduction, cell proliferation and differentiation, apoptosis and stress responses. The purpose of this review is to present recent knowledge about the role of miRNAs in asthma and outline possible applications of miRNAs.

RECENT FINDINGS

A core set of miRNAs involved in asthma includes downregulated let-7 family, miR-193b, miR-375 as well as upregulated miR-21, miR-223, miR-146a, miR-142-5p, miR-142-3p, miR-146b and miR-155. Recently it has been shown that most of the involved miRNAs increase secretion of Th2 cytokines, decrease secretion of Th1 cytokines, promote differentiation of T cells towards Th2 or play a role in hyperplasia and hypertrophy of bronchial smooth muscle cells. The profiles of miRNAs correlate with clinical characteristics, including lung function, phenotype and severity of asthma.

SUMMARY

Recent publications confirmed crucial regulatory role of miRNAs in the pathomechanism of asthma. Some single miRNAs or their sets hold the promise for their use as asthma biomarkers facilitating diagnosis or prediction of treatment outcomes. They are also possible target of future therapies. The studies in this field are lacking though.

Diagnostic and prognostic value of serum miR-9-5p and miR-128-3p levels in early-stage acute ischemic stroke

OBJECTIVES

To investigate the clinical utility of serum microRNA levels (miR-9-5p and miR-128-3p) in the diagnosis and prognosis of early-stage acute ischemic stroke (AIS).

METHODS

We compared the differences in serum miR-9-5p and miR-128-3p levels between patients with AIS and healthy individuals (controls). The serum levels of miR-9-5p and miR-128-3p were quantified using quantitative real-time PCR, and the association of each miRNA with AIS was determined using receiver operator characteristic curve analysis. The predictive value of these indices in the diagnosis of early-stage AIS was evaluated in conjunction with that of computed tomography findings and neuron-specific enolase levels. The prognosis of patients with AIS was evaluated three months after their discharge from hospital using the modified Rankin scale, which classifies the prognosis as either favorable or poor. Logistic regression analysis was used to analyze the correlation between miR-9-5p and miR-128-3p levels and patient prognosis.

RESULTS

The serum levels of miR-9-5p and miR-128-3p were upregulated in patients with AIS relative to those in healthy individuals. A pronounced correlation was identified between serum miR-9-5p and miR-128-3p levels and patient prognosis, with high levels of both miRNAs being associated with poor patient outcomes.

CONCLUSION

Assessment of serum miR-9-5p and miR-128-3p levels is important for the early diagnosis and prognosis of AIS.

A comprehensive analysis of microRNAs as diagnostic biomarkers for asthma

Background:

It is unclear whether microRNAs could be a potential diagnostic biomarker for asthma or not. The objective of this study is to figure out the diagnostic value of microRNAs in asthma.

Methods:

Literature retrieval, screening of publications, specific data extraction, and quality evaluation were conducted according to the standard criteria. Stata 14.0 software was used to analyze the diagnostic value of microRNA for asthma, including the combined sensitivity (Sen), specificity (Spe), the area under the curve (AUC), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR).

Results:

A total of 72 studies, containing 4143 cases and 2188 controls, were included for this comprehensive analysis. None of the included publications were rated low in quality. We summarized that, compared with controls, more than 100 miRNAs were reported differently expressed in asthma, although the expression trends were inconsistent. Besides, there were five studies among these 72 articles that applied the diagnostic evaluation of microRNAs in asthma. We found that the pooled Sen, Spe, and AUC for the combination of miR-185-5p, miR-155, let-7a, miR-21, miR-320a, miR-1246, miR-144-5p, and miR-1165-3p in asthma were 0.87 (95%CI: 0.72–0.95), 0.84 (95%CI: 0.74–0.91), and 0.93 (95%CI: 0.89–0.94) individually, and the PLR, NLR, and DOR were 5.5 (95%CI: 3.1–9.7), 0.15 (95%CI: 0.07–0.36), and 35 (95%CI: 10–127) in asthma, respectively. In terms of subgroup analyses, we found that the Sen for these combination miRNAs from serum was higher than that in plasma, while the Spe in plasma worked better than that in serum. Furthermore, compared with children, the combination of above miRNAs from adults had higher Spe and similar Sen.

Conclusions:

From our analysis, the combination of miR-185-5p, miR-155, let-7a, miR-21, miR-320a, miR-1246, miR-144-5p, and miR-1165-3p from peripheral blood could potentially act as a diagnostic biomarker for asthma.

The reviews of this paper are available via the supplemental material section.

Role of biomarkers and effect of FIP-fve in acute and chronic animal asthma models

BACKGROUND

Asthma is a consequence of complex gene-environment interactions. Exploring the heterogeneity of asthma in different stages is contributing to our understanding of its pathogenesis and the development of new therapeutic strategies, especially in severe cases.

OBJECTIVE

This study aimed to further understand the relationship between manifestations of acute and chronic asthma and various endotypes, and explore the severity of lung inflammation, cell types, cytokine/chemokine differences, and the effects of FIP-fve.

MATERIALS AND METHODS

Acute and chronic OVA-sensitization mouse asthma models, based on our previously published method, were used and FIP-fve was used to evaluate the effect on these two models. BALF cytokines/chemokines were detected according to the manufacturer's protocol.

RESULTS

Seventeen cytokine/chemokine secretions were higher in the chronic stage than in the acute stage. Whether in acute stage or chronic stage, the FIP-fve treatment groups had reduced airway hyperresponsiveness, infiltration of airway inflammatory cells, secretion of cytokines, chemokines by Th2 cells, and TNF-α, IL-8, IL-17, CXCL-1, CXCL-10, CCL-17, and CCL-22, and it was also found that the Treg cell cytokine IL-10 had increased significantly. PCA (Principal Component Analysis) was also used to compare statistics and laboratory data to find the important biomarkers in different stages and after treatment with FIP-fve.

CONCLUSIONS

There are many different immune responses in the different stages of the asthma process. Drug treatment at the appropriate times might help reduce the worsening of asthma.

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.