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

Eupalinolide B targets DEK and PANoptosis through E3 ubiquitin ligases RNF149 and RNF170 to negatively regulate asthma

PURPOSE

We investigated the mechanism by which eupalinolide B (EB) regulates DEK protein ubiquitination and degradation, and its impact on DEK-mediated receptor-interacting protein kinase 1 (RIPK)-PANoptosis pathway in allergic asthma.

STUDY DESIGN AND METHODS

In vitro studies were conducted on human bronchial epithelial cells (BEAS-2B) treated with EB and human-recombinant DEK. Mass spectrometry analysis, RNA sequencing, molecular docking, and functional assays were used to assess the interactions and effects of EB, DEK, and ring finger protein 149 and 170 (RNF149 and RNF170). In vivo experiments involved a house dust mite-induced asthma model in mice and evaluation of airway inflammation, DEK expression, and PANoptosis markers.

RESULTS

In vitro, EB could bind to DEK. RNF149 and RNF170 were identified as regulatory factors of DEK, polyubiquitinating the K349 site in the DEK coding DNA sequence region 270-350 through K48 linkages and leading to its degradation. RNA sequencing showed that DEK overexpression upregulated the expression of genes such as RIPK1, FADD, and Caspase 8. Treatment with DEK siRNA or EB reduced the activation of the RIPK1-PANoptosis pathway in BEAS-2B-DEK cells. In vivo, EB significantly reduced the levels of DEK in house dust mite-induced mice and alleviated pulmonary inflammatory cell infiltration, goblet cell hyperplasia, collagen fiber deposition, and eosinophil proportion in BALF. Knocking out the DEK gene reduced RIPK1-induced PANoptosis, and inhibited airway inflammation and cell apoptosis.

CONCLUSION

EB promotes the degradation of DEK by RNF149 and RNF170, inhibits the RIPK1-PANoptosis pathway, and may effectively suppress asthma. EB may become a potential drug for treating airway inflammation in asthma.

Therapeutic Potential of Exosomal miRNAs: New Insights and Future Directions

Modern advancements in medicine include developing targeted drug delivery systems in the medical field, which are designed to unravel the potential of therapeutic products and overcome the barriers to the effectiveness of current approaches. Various nanopolymer carrier systems have been introduced in this regard, and the simple characteristics of extracellular vesicles have drawn special attention to their application as an effective drug delivery tool. Exosomes are very similar to transport vesicles and have a lipid-biomembrane covering an aqueous core. They also contain both hydrophilic and lipophilic substances and deliver their cargo to the desired targets. These properties enable exosomes to overcome some of the limitations of liposomes. Exosomes can easily diffuse into body fluids and remain in the bloodstream for a long time, crossing physiological barriers and entering cells. Exosomes, which contain a large volume of biomolecules, do not stimulate immune responses and do not accumulate in the liver or lungs instead of target tissues. Recent advancements in regenerative medicine have enabled scientists to utilize exosomes extracted from mesenchymal stem cells (MSCs), which possess significant regenerative abilities, for treating various diseases. The contents of these exosomes are crucial for both diagnosis and treatment, as they influence disease progression. Numerous in vitro studies have confirmed the safety, effectiveness, and therapeutic promise of exosomes in conditions such as cancer, neurodegenerative disorders, cardiovascular issues, and orthopedic ailments. This article explores the therapeutic potential of MSC-derived exosomes and outlines the essential procedures for their preparation.

MiR-340-5p alleviates AECOPD by targeting MAP3K2 via Qingjin Huatan decoction therapy

Chronic obstructive pulmonary disease (COPD) features persistent inflammation and restricted airflow, with acute exacerbations of COPD (AECOPD) significantly worsening patient outcomes. This study aims to explore the role of Qingjin Huatan Decoction (QJHTT) on AECOPD with the syndrome of phlegm-heat obstruction of the lung. AECOPD was induced in male Sprague-Dawley rats using lipopolysaccharide and cigarette smoke exposure. Rats were treated with varying doses of QJHTT. miR-340-5p expression was quantified using qPCR. Lung histopathology was assessed with hematoxylin and eosin staining, and interleukin-6, interleukin-1 beta, and tumor necrosis factor-alpha were measured by enzyme-linked immunosorbent assay (ELISA). The effects on cell viability and apoptosis in primary airway epithelial cells were evaluated using Cell Counting Kit-8 and flow cytometry assays, respectively. The dual-luciferase reporter assay validated the interaction between miR-340-5p and mitogen-activated protein kinase kinase kinase 2 (MAP3K2), and protein expression was analyzed by Western blot. QJHTT improved lung histopathology, reducing inflammatory cell infiltration, and alveolar damage. ELISA results showed reduced inflammatory cytokine levels in QJHTT-treated groups (P < 0.05). qPCR analysis demonstrated that QJHTT upregulated miR-340-5p expression (P < 0.05). miR-340-5p mimic enhanced cell viability and reduced apoptosis in primary airway epithelial cells (P < 0.05). Dual-luciferase reporter assay confirmed that miR-340-5p directly targets MAP3K2, leading to its downregulation (P < 0.05). QJHTT exerts therapeutic effects in phlegm-heat obstructing the lung type of AECOPD through upregulating miR-340-5p and inhibiting MAP3K2. This study highlights the QJHTT and miR-340-5p/MAP3K2 pathway for this disease treatment.

Matrix metalloproteinase 7 (MMP7) as a molecular target for Mycoplasma gallisepticum (MG) resistance in chickens

Mycoplasma gallisepticum (MG) causes chronic respiratory disease (CRD), posing a significant threat to global poultry production. Current preventive strategies face limitations, emphasizing the need for alternative approaches such as breeding for disease resistance. This study identifies the matrix metalloproteinase 7 (MMP7) gene as a key factor in CRD resistance. Analysis of high-throughput sequencing data revealed MMP7's association with MG infection at tissue and cellular levels. Overexpression of MMP7 in avian type II alveolar epithelial cells (AECII) and macrophages (HD11) inhibited MG adhesion, modulated immune responses, and suppressed MG-induced cell proliferation and apoptosis, though MG replication remained unaffected. Conversely, MMP7 inhibition enhanced MG infection. Experimental infections in commercial (Jingfen Layer No.6, Hy-Line White) and local Chinese chicken breeds (Guangxi Indigenous, Tianlu Partridge, Cyan Shank Partridge) validated Tianlu Partridge chickens' relative resistance and Jingfen Layers' susceptibility. MMP7 expression levels correlated positively with reduced chick weight, air sac damage, tracheal mucosal thickness, and MG lung loads. These findings highlight MMP7 as a molecular target for assessing MG susceptibility and breeding resistant chickens while demonstrating the utility of local Chinese breeds in resistance-focused breeding programs.

Diagnostic value of miR-193a-5p in severe pneumonia and its correlation with prognosis

BACKGROUND

Severe pneumonia is a common disease in children, with rapid progression and easy complications of respiratory failure, endangering the lives of children. This study aimed to elucidate the clinical significance of miR-193a-5p in severe pneumonia and to provide a new biomarker for the disease.

METHODS

A total of 150 children with severe pneumonia and an equal number of healthy children were selected for analysis. Serum miR-193a-5p levels were detected by RT-qPCR. The correlation of miR-193a-5p with CRP, WBC, neutrophil count, and NLR was assessed by Spearman analysis. The diagnostic and prognostic value of miR-193a-5p in severe pneumonia was analyzed using ROC curves. The relationship between miR-193a-5p and the prognosis of severe pneumonia was evaluated using the Kaplan-Meier curve and a multivariate logistic analysis.

RESULTS

Serum levels of miR-193a-5p were markedly elevated in children with severe pneumonia and exhibited a positive correlation with CRP, WBC, neutrophil count, and NLR. miR-193a-5p could effectively distinguish children with severe pneumonia from healthy children, with an AUC, sensitivity, and specificity of 0.862, 70.67%, and 88.67%, respectively. Serum miR-193a-5p expression was increased in children with poor prognosis and had a predictive value for patient prognosis. High expression of miR-193a-5p was linked to survival in children with severe pneumonia and was a risk factor for adverse prognosis.

CONCLUSION

Serum levels of miR-193a-5p were markedly elevated in children with severe pneumonia, which may be of significance for the early diagnosis of the disease and prognostic assessment.

Exosomes to exosome-functionalized scaffolds: a novel approach to stimulate bone regeneration

Bone regeneration is a complex biological process that relies on the orchestrated interplay of various cellular and molecular events. Bone tissue engineering is currently the most promising method for treating bone regeneration. However, the immunogenicity, stable and cell quantity of seed cells limited their application. Recently, exosomes, which are small extracellular vesicles released by cells, have been found to effectively address these problems and better induce bone regeneration. Meanwhile, a growing line of research has shown the cargos of exosomes may provide effective therapeutic and biomarker tools for bone repair, including miRNA, lncRNA, and proteins. Moreover, engineered scaffolds loaded with exosomes can offer a cell-free bone repair strategy, addressing immunogenicity concerns and providing a more stable functional performance. Herein, we provide a comprehensive summary of the role played by scaffolds loaded with exosomes in bone regeneration, drawing on a systematic analysis of relevant literature available on PubMed, Scopus, and Google Scholar database.

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.

Extracellular Vesicles From Mycoplasma gallisepticum: Modulators of Macrophage Activation and Virulence

Extracellular vesicles (EVs) mediate intercellular communication by transporting proteins. To investigate the pathogenesis of Mycoplasma gallisepticum, a major threat to the poultry industry, we isolated and characterized M. gallisepticum-produced EVs. Our study highlights the significant impact of M. gallisepticum-derived EVs on immune function and macrophage apoptosis, setting them apart from other M. gallisepticum metabolites. These EVs dose-dependently enhance M. gallisepticum adhesion and proliferation, simultaneously modulating Toll-like receptor 2 and interferon γ pathways and thereby inhibiting macrophage activation. A comprehensive protein analysis revealed 117 proteins in M. gallisepticum-derived EVs, including established virulence factors, such as GapA, CrmA, VlhA, and CrmB. Crucially, these EV-associated proteins significantly contribute to M. gallisepticum infection. Our findings advance our comprehension of M. gallisepticum pathogenesis, offering insights for preventive strategies and emphasizing the pivotal role of M. gallisepticum-derived EVs and their associated proteins. This research sheds light on the composition and crucial role of M. gallisepticum-derived EVs in M. gallisepticum pathogenesis, aiding our fight against M. gallisepticum infections.

Mesenchymal stem cell-derived exosomes as delivery vehicles for non-coding RNAs in lung diseases

The burden of lung diseases is gradually increasing with an increase in the average human life expectancy. Therefore, it is necessary to identify effective methods to treat lung diseases and reduce their social burden. Currently, an increasing number of studies focus on the role of mesenchymal stem cell-derived exosomes (MSC-Exos) as a cell-free therapy in lung diseases. They show great potential for application to lung diseases as a more stable and safer option than traditional cell therapies. MSC-Exos are rich in various substances, including proteins, nucleic acids, and DNA. Delivery of Non-coding RNAs (ncRNAs) enables MSC-Exos to communicate with target cells. MSC-Exos significantly inhibit inflammatory factors, reduce oxidative stress, promote normal lung cell proliferation, and reduce apoptosis by delivering ncRNAs. Moreover, MSC-Exos carrying specific ncRNAs affect the proliferation, invasion, and migration of lung cancer cells, thereby playing a role in managing lung cancer. The detailed mechanisms of MSC-Exos in the clinical treatment of lung disease were explored by developing standardized culture, isolation, purification, and administration strategies. In summary, MSC-Exo-based delivery methods have important application prospects for treating lung diseases.