Extracellular vesicles from human airway basal cells respond to cigarette smoke extract and affect vascular endothelial cells

Environmental pollutants exposure-derived extracellular vesicles: crucial players in respiratory disorders

BACKGROUND

Individual exposure to environmental pollutants, as one of the most influential drivers of respiratory disorders, has received considerable attention due to its preventability and controllability. Considering that the extracellular vesicle (EV) was an emerging intercellular communication medium, recent studies have highlighted the crucial role of environmental pollutants derived EVs (EPE-EVs) in respiratory disorders.

METHODS

PubMed and Web of Science were searched from January 2018 to December 2023 for publications with key words of environmental pollutants, respiratory disorders and EVs.

RESULTS

Environmental pollutants could disrupt airway intercellular communication by indirectly stimulating airway barrier cells to secrete endogenous EVs, or directly transmitting exogenous EVs, mainly by biological pollutants. Mechanistically, EPE-EVs transferred specific contents to modulate biological functions of recipient cells, to induce respiratory inflammation and impair tissue and immune function, which consequently contributed to the development of respiratory diseases, such as asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, pulmonary hypertension, lung cancer and infectious lung diseases. Clinically, EVs could emerged as promising biomarkers and biological agents for respiratory diseases attributed by their specificity, convenience, sensibility and stability.

CONCLUSIONS

Further studies of EPE-EVs are helpful to understand the aetiology and pathology of respiratory diseases, and facilitate the precision respiratory medicine in risk screening, early diagnosis, clinical management and biotherapy.

Effectiveness of extracellular vesicles derived from hiPSCs in repairing hyperoxia-induced injury in a fetal murine lung explant model

BACKGROUND

Despite advances in neonatal care, the incidence of Bronchopulmonary Dysplasia (BPD) remains high among preterm infants. Human induced pluripotent stem cells (hiPSCs) have shown promise in repairing injury in animal BPD models. Evidence suggests they exert their effects via paracrine mechanisms. We aim herein to assess the effectiveness of extracellular vesicles (EVs) derived from hiPSCs and their alveolar progenies (diPSCs) in attenuating hyperoxic injury in a preterm lung explant model.

METHODS

Murine lung lobes were harvested on embryonic day 17.5 and maintained in air-liquid interface. Following exposure to 95% O2 for 24 h, media was supplemented with 5 × 106 particles/mL of EVs isolated from hiPSCs or diPSCs by size-exclusion chromatography. On day 3, explants were assessed using Hematoxylin-Eosin staining with mean linear intercept (MLI) measurements, immunohistochemistry, VEGFa and antioxidant gene expression. Statistical analysis was conducted using one-way ANOVA and Multiple Comparison Test. EV proteomic profiling was performed, and annotations focused on alveolarization and angiogenesis signaling pathways, as well as anti-inflammatory, anti-oxidant, and regenerative pathways.

RESULTS

Exposure of fetal lung explants to hyperoxia induced airspace enlargement, increased MLI, upregulation of anti-oxidants Prdx5 and Nfe2l2 with decreased VEGFa expression. Treatment with hiPSC-EVs improved parenchymal histologic changes. No overt changes in vasculature structure were observed on immunohistochemistry in our in vitro model. However, VEGFa and anti-oxidant genes were upregulated with diPSC-EVs, suggesting a pro-angiogenic and cytoprotective potential. EV proteomic analysis provided new insights in regard to potential pathways influencing lung regeneration.

CONCLUSION

This proof-of-concept in vitro study reveals a potential role for hiPSC- and diPSC-EVs in attenuating lung changes associated with prematurity and oxygen exposure. Our findings pave the way for a novel cell free approach to prevent and/or treat BPD, and ultimately reduce the global burden of the disease.

Effect of environmental exposures on cancer risk: Emerging role of non-coding RNA shuttled by extracellular vesicles

Environmental and lifestyle exposures have a huge impact on cancer risk; nevertheless, the biological mechanisms underlying this association remain poorly understood. Extracellular vesicles (EVs) are membrane-enclosed particles actively released by all living cells, which play a key role in intercellular communication. EVs transport a variegate cargo of biomolecules, including non-coding RNA (ncRNA), which are well-known regulators of gene expression. Once delivered to recipient cells, EV-borne ncRNAs modulate a plethora of cancer-related biological processes, including cell proliferation, differentiation, and motility. In addition, the ncRNA content of EVs can be altered in response to outer stimuli. Such changes can occur either as an active attempt to adapt to the changing environment or as an uncontrolled consequence of cell homeostasis loss. In either case, such environmentally-driven alterations in EV ncRNA might affect the complex crosstalk between malignant cells and the tumor microenvironment, thus modulating the risk of cancer initiation and progression. In this review, we summarize the current knowledge about EV ncRNAs at the interface between environmental and lifestyle determinants and cancer. In particular, we focus on the effect of smoking, air and water pollution, diet, exercise, and electromagnetic radiation. In addition, we have conducted a bioinformatic analysis to investigate the biological functions of the genes targeted by environmentally-regulated EV microRNAs. Overall, we draw a comprehensive picture of the role of EV ncRNA at the interface between external factors and cancer, which could be of great interest to the development of novel strategies for cancer prevention, diagnosis, and therapy.

Exploring salivary exosomes as early predictors of oral cancer in susceptible tobacco consumers: noninvasive diagnostic and prognostic applications

BACKGROUND

Salivary exosome analysis provides a noninvasive and comprehensive approach with potential applications in oral cancer diagnosis and prognosis. The early detection of oral cancer has remained a critical concern in enhancing the quality of life, especially for individuals who consume tobacco and are at greater risk of developing the disease. The current study investigates the potential of salivary exosomes in screening smokers for early signs and transformations of oral cancer.

METHODS

Morphological characterization of salivary exosomes among three study groups (non-smokers as control, smokers as high-risk tobacco consumers, and Oral cancer) (n = 120) was carried out through dynamic light scattering, and nanoparticle tracking analysis. For molecular characterization, EXOCET and Fourier transform infrared spectroscopy methods were utilized. The expression of the exosomal surface protein CD63 was evaluated using Western blotting.

RESULTS

Salivary exosomes exhibit noticeable differences in size between control group and tobacco consumers. The differentiation extended beyond exosome size and included variations in concentration and bio-molecular composition, as determined by FTIR screening. Tobacco consumers and oral cancer groups showed significantly larger and more concentrated exosomes compared to the healthy group.

CONCLUSION

Our study provides strong evidence that the properties of salivary exosomes can serve as reliable noninvasive biomarkers for distinguishing tobacco consumers from non-smokers and oral cancer patients. Our results underscore the potential of exosome-based diagnostics in early oral cancer detection for high-risk individuals. The larger size and higher concentration of exosomes in tobacco consumers indicate early changes in cell secretions associated with the transformation from healthy to abnormal cells.

Phospholipid fatty acid remodeling and carbonylated protein increase in extracellular vesicles released by airway epithelial cells exposed to cigarette smoke extract

Cigarette smoke (CS) represents one of the most relevant environmental risk factors for several chronic pathologies. Tissue damage caused by CS exposure is mediated, at least in part, by oxidative stress induced by its toxic and pro-oxidant components. Evidence demonstrates that extracellular vesicles (EVs) released by various cell types exposed to CS extract (CSE) are characterized by altered biochemical cargo and gained pathological properties. In the present study, we evaluated the content of oxidized proteins and phospholipid fatty acid profiles of EVs released by human bronchial epithelial BEAS-2B cells treated with CSE. This specific molecular characterization has hitherto not been performed. After confirmation that CSE reduces viability of BEAS-2B cells and elevates intracellular ROS levels, in a dose-dependent manner, we demonstrated that 24 h exposure at 1% CSE, a concentration that only slight modifies cell viability but increases ROS levels, was able to increase carbonylated protein levels in cells and released EVs. The release of oxidatively modified proteins via EVs might represent a mechanism used by cells to remove toxic proteins in order to avoid their intracellular overloading. Moreover, 1% CSE induced only few changes in the fatty acid asset in BEAS-2B cell membrane phospholipids, whereas several rearrangements were observed in EVs released by CSE-treated cells. The impact of changes in acyl chain composition of CSE-EVs accounted for the increased saturation levels of phospholipids, a membrane parameter that might influence EV stability, uptake and, at least in part, EV-mediated biological effects. The present in vitro study adds new information concerning the biochemical composition of CSE-related EVs, useful to predict their biological effects on target cells. Furthermore, the information regarding the presence of oxidized proteins and the specific membrane features of CSE-related EVs can be useful to define the utilization of circulating EVs as marker for diagnosing of CS-induced lung damage and/or CS-related diseases.

Extracellular Vesicles (EVs) as Crucial Mediators of Cell-Cell Interaction in Asthma

Asthma is the most common chronic respiratory disorder worldwide and accounts for a huge health and economic burden. Its incidence is rapidly increasing but, in parallel, novel personalized approaches have emerged. Indeed, the improved knowledge of cells and molecules mediating asthma pathogenesis has led to the development of targeted therapies that significantly increased our ability to treat asthma patients, especially in severe stages of disease. In such complex scenarios, extracellular vesicles (EVs i.e., anucleated particles transporting nucleic acids, cytokines, and lipids) have gained the spotlight, being considered key sensors and mediators of the mechanisms controlling cell-to-cell interplay. We will herein first revise the existing evidence, mainly by mechanistic studies in vitro and in animal models, that EV content and release is strongly influenced by the specific triggers of asthma. Current studies indicate that EVs are released by potentially all cell subtypes in the asthmatic airways, particularly by bronchial epithelial cells (with different cargoes in the apical and basolateral side) and inflammatory cells. Such studies largely suggest a pro-inflammatory and pro-remodelling role of EVs, whereas a minority of reports indicate protective effects, particularly by mesenchymal cells. The co-existence of several confounding factors-including technical pitfalls and host and environmental confounders-is still a major challenge in human studies. Technical standardization in isolating EVs from different body fluids and careful selection of patients will provide the basis for obtaining reliable results and extend their application as effective biomarkers in asthma.

Do Circulating Extracellular Vesicles Strictly Reflect Bronchoalveolar Lavage Extracellular Vesicles in COPD?

Cell-derived extracellular vesicles (EVs) found in the circulation and body fluids contain biomolecules that could be used as biomarkers for lung and other diseases. EVs from bronchoalveolar lavage (BAL) might be more informative of lung abnormalities than EVs from blood, where information might be diluted. To compare EVs' characteristics in BAL and blood in smokers with and without COPD. Same-day BAL and blood samples were obtained in 9 nonsmokers (NS), 11 smokers w/o COPD (S), and 9 with COPD (SCOPD) (FEV1: 59 ± 3% pred). After differential centrifugation, EVs (200-500 nm diameter) were identified by flow cytometry and labeled with cell-type specific antigens: CD14 for macrophage-derived EVs, CD326 for epithelial-derived EVs, CD146 for endothelial-derived EVs, and CD62E for activated-endothelial-derived EVs. In BAL, CD14-EVs were increased in S compared to NS [384 (56-567) vs. 172 (115-282) events/μL; p = 0.007] and further increased in SCOPD [619 (224-888)] compared to both S (p = 0.04) and NS (p < 0.001). CD326-EVs were increased in S [760 (48-2856) events/μL, p < 0.001] and in SCOPD [1055 (194-11,491), p < 0.001] when compared to NS [15 (0-68)]. CD146-EVs and CD62E-EVs were similar in the three groups. In BAL, significant differences in macrophage and epithelial-derived EVs can be clearly detected between NS, S and SCOPD, while these differences were not found in plasma. This suggests that BAL is a better medium than blood to study EVs in lung diseases.

Initial and ongoing tobacco smoking elicits vascular damage and distinct inflammatory response linked to neurodegeneration

Tobacco smoking is strongly linked to vascular damage contributing to the development of hypertension, atherosclerosis, as well as increasing the risk for neurodegeneration. Still, the involvement of the innate immune system in the development of vascular damage upon chronic tobacco use before the onset of clinical symptoms is not fully characterized. Our data provide evidence that a single acute exposure to tobacco elicits the secretion of extracellular vesicles expressing CD105 and CD49e from endothelial cells, granting further recognition of early preclinical biomarkers of vascular damage. Furthermore, we investigated the effects of smoking on the immune system of healthy asymptomatic chronic smokers compared to never-smokers, focusing on the innate immune system. Our data reveal a distinct immune landscape representative for early stages of vascular damage in clinically asymptomatic chronic smokers, before tobacco smoking related diseases develop. These results indicate a dysregulated immuno-vascular axis in chronic tobacco smokers that are otherwise considered as healthy individuals. The distinct alterations are characterized by increased CD36 expression by the blood monocyte subsets, neutrophilia and increased plasma IL-18 and reduced levels of IL-33, IL-10 and IL-8. Additionally, reduced levels of circulating BDNF and elevated sTREM2, which are associated with neurodegeneration, suggest a considerable impact of tobacco smoking on CNS function in clinically healthy individuals. These findings provide profound insight into the initial and ongoing effects of tobacco smoking and the potential vascular damage contributing to neurodegenerative disorders, specifically cerebrovascular dysfunction and dementia.

The impact of environmental contaminants on extracellular vesicles and their key molecular regulators: A literature and database-driven review

Exposure to environmental chemicals is now well recognized as a significant factor contributing to the global burden of disease; however, there remain critical gaps in understanding the types of biological mechanisms that link environmental chemicals to adverse health outcomes. One type of mechanism that remains understudied involves extracellular vesicles (EVs), representing small cell-derived particles capable of carrying molecular signals such as RNAs, miRNAs, proteins, lipids, and chemicals through biological fluids and imparting beneficial, neutral, or negative effects on target cells. In fact, evidence is just now starting to grow that supports the role of EVs in various disease etiologies. This review aims to (1) Provide a landscape of the current understanding of the functional relationship between EVs and environmental chemicals; (2) Summarize current knowledge of EV regulatory processes including production, packaging, and release; and (3) Conduct a database-driven analysis of known chemical-gene interactions to predict and prioritize environmentally relevant chemicals that may impact EV regulatory genes and thus EV regulatory processes. This approach to predicting environmentally relevant chemicals that may alter EVs provides a novel method for evidence-based hypothesis generation for future studies evaluating the link between environmental exposures and EVs.

Hesperidin inhibits tobacco smoke-induced pulmonary cell proliferation and EMT in mouse lung tissues via the p38 signaling pathway

Tobacco smoke (TS) is the major cause of lung cancer. The abnormal proliferation and epithelial-mesenchymal transition (EMT) of lung cells promote occurrence and development of lung cancer. The p38 pathway intervenes in this cancer development. Hesperidin also serves a role in human health and disease prevention. The roles of p38 in TS-mediated abnormal cell proliferation and EMT, and the hesperidin intervention thereof are not yet understood. In the present study, it was demonstrated that TS upregulated proliferating cell nuclear antigen, vimentin and N-cadherin expression, whereas it downregulated E-cadherin expression, as assessed using western blotting and reverse transcription-quantitative PCR. Furthermore, it was observed that inhibition of the p38 pathway inhibit TS-induced proliferation and EMT. Hesperidin treatment prevented the TS-induced activation of the p38 pathway, EMT and cell proliferation in mouse lungs. The findings of the present study may provide insights into the pathogenesis of TS-related lung cancer.

Environmental Exposures and Extracellular Vesicles: Indicators of Systemic Effects and Human Disease

PURPOSE OF REVIEW

Environmental pollutants contribute to the pathogenesis of numerous diseases including chronic cardiovascular, respiratory, and neurodegenerative diseases, among others. Emerging evidence suggests that extracellular vesicles (EVs) may mediate the association of environmental exposures with chronic diseases. The purpose of this review is to describe the impact of common environmental exposures on EVs and their role in linking environmental pollutants to the pathogenesis of chronic systemic diseases.

RECENT FINDINGS

Common environmental pollutants including particulate matter, tobacco smoke, and chemical pollutants trigger the release of EVs from multiple systems in the body. Existing research has focused primarily on air pollutants, which alter EV production and release in the lungs and systemic circulation. Air pollutants also impact the selective loading of EV cargo including microRNA and proteins, which modify the cellular function in recipient cells. As a result, pollutant-induced EVs often contribute to a pro-inflammatory and pro-thrombotic milieu, which increases the risk of pollutant-related diseases including obstructive lung diseases, cardiovascular disease, neurodegenerative diseases, and lung cancer. Common environmental exposures are associated with multifaceted changes in EVs that lead to functional alterations in recipient cells and contribute to the pathogenesis of chronic systemic diseases. EVs may represent emerging targets for the prevention and treatment of diseases that stem from environmental exposures. However, novel research is required to expand our knowledge of the biological action of EV cargo, elucidate determinants of EV release, and fully understand the impact of environmental pollutants on human health.

Endothelial Dysfunction through Oxidatively Generated Epigenetic Mark in Respiratory Viral Infections

The bronchial vascular endothelial network plays important roles in pulmonary pathology during respiratory viral infections, including respiratory syncytial virus (RSV), influenza A(H1N1) and importantly SARS-Cov-2. All of these infections can be severe and even lethal in patients with underlying risk factors.A major obstacle in disease prevention is the lack of appropriate efficacious vaccine(s) due to continuous changes in the encoding capacity of the viral genome, exuberant responsiveness of the host immune system and lack of effective antiviral drugs. Current management of these severe respiratory viral infections is limited to supportive clinical care. The primary cause of morbidity and mortality is respiratory failure, partially due to endothelial pulmonary complications, including edema. The latter is induced by the loss of alveolar epithelium integrity and by pathological changes in the endothelial vascular network that regulates blood flow, blood fluidity, exchange of fluids, electrolytes, various macromolecules and responses to signals triggered by oxygenation, and controls trafficking of leukocyte immune cells. This overview outlines the latest understanding of the implications of pulmonary vascular endothelium involvement in respiratory distress syndrome secondary to viral infections. In addition, the roles of infection-induced cytokines, growth factors, and epigenetic reprogramming in endothelial permeability, as well as emerging treatment options to decrease disease burden, are discussed.