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

Roles of Exosomal miRNAs in Asthma: Mechanisms and Applications

Asthma is a chronic inflammatory disorder of the airways, characterized by a complex interplay of genetic, environmental, and immunological factors that contribute to its onset and progression. Recent advances in researches have illuminated the critical role of exosomal microRNAs (miRNAs) in the pathogenesis and development of asthma. Exosomes are nano-sized extracellular vesicles that facilitate intercellular communication by transporting a variety of bioactive molecules, including miRNAs, and play a crucial role in regulating gene expression and immune responses, which are central to the inflammatory processes underlying asthma. Exosomal miRNAs are emerging as key players in asthma due to their involvement in various aspects of the disease, including the regulation of inflammation, airway hyperresponsiveness, and remodeling. Their ability to influence the behavior of target cells and tissues makes them valuable both as diagnostic biomarkers and as potential therapeutic targets. This review aims to provide a comprehensive overview of the biogenesis of exosomes, the functional roles of exosomal miRNAs in asthma, and their clinical potential. It will explore the mechanisms by which these miRNAs contribute to asthma pathophysiology, discuss their utility in diagnosing and monitoring the disease, and highlight ongoing research efforts to harness their therapeutic potential.

Extracellular Vesicle microRNA: A Promising Biomarker and Therapeutic Target for Respiratory Diseases

Respiratory diseases, including chronic obstructive pulmonary disease (COPD), asthma, lung cancer, and coronavirus pneumonia, present a major global health challenge. Current diagnostic and therapeutic options for these diseases are limited, necessitating the urgent development of novel biomarkers and therapeutic strategies. In recent years, microRNAs (miRNAs) within extracellular vesicles (EVs) have received considerable attention due to their crucial role in intercellular communication and disease progression. EVs are membrane-bound structures released by cells into the extracellular environment, encapsulating a variety of biomolecules such as DNA, RNA, lipids, and proteins. Specifically, miRNAs within EVs, known as EV-miRNAs, facilitate intercellular communication by regulating gene expression. The expression levels of these miRNAs can reflect distinct disease states and significantly influence immune cell function, chronic airway inflammation, airway remodeling, cell proliferation, angiogenesis, epithelial-mesenchymal transition, and other pathological processes. Consequently, EV-miRNAs have a profound impact on the onset, progression, and therapeutic responses of respiratory diseases, with great potential for disease management. Synthesizing the current understanding of EV-miRNAs in respiratory diseases such as COPD, asthma, lung cancer, and novel coronavirus pneumonia, this review aims to explore the potential of EV-miRNAs as biomarkers and therapeutic targets and examine their prospects in the diagnosis and treatment of these respiratory diseases.

Breath and Sputum Analyses in Asthmatic Patients: An Overview

Recent advancements in asthma management include non-invasive methodologies such as sputum analysis, exhaled breath condensate (EBC), and fractional exhaled nitric oxide (FeNO). These techniques offer a means to assess airway inflammation, a critical feature of asthma, without invasive procedures. Sputum analysis provides detailed insights into airway inflammation patterns and cellular composition, guiding personalized treatment strategies. EBC collection, reflecting bronchoalveolar lining fluid composition, provides a non-invasive window into airway physiology. FeNO emerges as a pivotal biomarker, offering insights into eosinophilic airway inflammation and aiding in asthma diagnosis, treatment monitoring, and the prediction of exacerbation risks. Despite inherent limitations, each method offers valuable tools for a more comprehensive assessment of asthma. Combining these techniques with traditional methods like spirometry may lead to more personalized treatment plans and improved patient outcomes. Future research is crucial to refine protocols, validate biomarkers, and establish comprehensive guidelines in order to enhance asthma management with tailored therapeutic strategies and improved patient outcomes.

Serum exosomal miR-141-3p and miR-3679-5p levels associated with endotype and postoperative recurrence in chronic rhinosinusitis with nasal polyps

Background

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease. Exosomes were involved in different inflammatory diseases, but their roles in CRSwNP were poorly explored.

Method

We collected serum samples from 8 CRSwNP patients and 8 healthy controls (HC) and isolated their exosomes. MiRNA sequencing was performed for the exosome samples and differentially expressed miRNAs were identified. The top 3 differentially expressed exosomal miRNAs were confirmed in 2 validation cohorts, and their diagnostic values, predictive values for eosinophilic endotype, and recurrence were evaluated.

Results

Distinctive serum exosomal miRNA profiles were observed between CRSwNP and HC groups. Reverse transcription-polymerase chain reaction results in the first validation cohort revealed that serum exosomal miR-141-3p levels were increased, and miR-18a-5p and miR-3679-5p levels were decreased in the CRSwNP group compared to the HC group. These 3 miRNAs were further validated in the second validation cohort, and the results showed that miR-141-3p levels were elevated and miR-3679-5p levels were reduced in the serum exosomes in the eosinophilic CRSwNP group in comparison with the non-eosinophilic CRSwNP group. Receiver operating characteristic (ROC) curves highlighted that exosomal miR-141-3p and miR-3679-5p exhibited promising values for predicting the eosinophilic endotype. The patients in the second cohort were followed up for 2 years, and categorized into recurrence and non-recurrence groups. The serum exosomal miR-141-3p levels were increased and miR-3679-5p levels were reduced in the recurrence group in comparison with the non-recurrence group. ROC curves and Kaplan-Meier survival analysis revealed significant associations between the levels of exosomal miR-141-3p and miR-3679-5p and the risk of postoperative recurrence.

Conclusions

This study identified unique miRNA expression patterns in serum exosomes of CRSwNP patients. Circulating exosomal miR-141-3p and miR-3679-5p emerged as novel biomarkers for diagnosing CRSwNP, predicting the eosinophilic endotype, and forecasting postoperative recurrence.

Blood miRNAs as Potential Diagnostic Biomarkers for Chronic Obstructive Pulmonary Disease: A Meta-Analysis

Purpose

Investigate the efficacy of blood microRNAs (miRNAs) as diagnostic biomarkers for Chronic Obstructive Pulmonary Disease (COPD).

Patients and Methods

We conducted a comprehensive search in English and Chinese databases, selecting studies based on predetermined criteria. Diagnostic parameters like summarized sensitivity (SSEN), summarized specificity (SSPE), summarized positive likelihood ratio (SPLR), summarized negative likelihood ratio (SNLR), and diagnostic odds ratio (DOR), and area under the curve (AUC) of the summary receiver operating characteristic (SROC) curves were analyzed using a bivariate model. Each parameter was accompanied by a 95% confidence interval (CI).

Results

Eighteen high-quality studies were included. For diagnosing COPD with blood miRNAs, the SSEN was 0.83 (95% CI 0.76-0.89), SSPE 0.76 (95% CI 0.70-0.82), SPLR 3.50 (95% CI 2.66-4.60), SNLR 0.22 (95% CI 0.15-0.33), DOR 15.72 (95% CI 8.58-28.77), and AUC 0.86 (95% CI 0.82-0.88). In acute exacerbations, SSEN was 0.85 (95% CI 0.76-0.91), SSPE 0.80 (95% CI 0.73-0.86), SPLR 4.26 (95% CI 3.05-5.95), SNLR 0.19 (95% CI 0.12-0.30), DOR 22.29 (95% CI 11.47-43.33), and AUC 0.89 (95% CI 0.86-0.91).

Conclusion

Blood miRNAs demonstrate significant accuracy in diagnosing COPD, both in general and during acute exacerbations, suggesting their potential as reliable biomarkers.

Tuning into miRNAs: A comprehensive analysis of their impact on diagnosis, and progression in asthma

Asthma is a diverse inflammatory illness affecting the respiratory passages, leading to breathing challenges, bouts of coughing and wheezing, and, in severe instances, significant deterioration in quality of life. Epigenetic regulation, which involves the control of gene expression through processes such as post-transcriptional modulation of microRNAs (miRNAs), plays a role in the evolution of various asthma subtypes. In immune-mediated diseases, miRNAs play a regulatory role in the behavior of cells that form the airway structure and those responsible for defense mechanisms in the bronchi and lungs. They control various cellular processes such as survival, growth, proliferation, and the production of chemokines and immune mediators. miRNAs possess chemical and biological characteristics that qualify them as suitable biomarkers for diseases. They allow for the categorization of patients to optimize drug selection, thus streamlining clinical management and decreasing both the economic burden and the necessity for critical care related to the disease. This study provides a concise overview of the functions of miRNAs in asthma and elucidates their regulatory effects on the underlying processes of the disease. We provide a detailed account of the present status of miRNAs as biomarkers for categorizing asthma, identifying specific asthma subtypes, and selecting appropriate treatment options.