Circulating endothelial microparticles as a measure of early lung destruction in cigarette smokers

Cigarette smoke-exposed microparticles released from T lymphocytes contribute to autophagy and apoptosis dysfunction in pulmonary microvascular endothelial cells

Cigarette smoke can cause dysfunction of the vascular endothelium; however, the underlying mechanisms have not been fully elucidated. We hypothesized that T lymphocyte-derived microparticles (TLMPs) are involved in cigarette-related diseases, especially those involving the vascular endothelium. The effect of cigarette smoke on the release of microparticles from human lymphocytes was investigated. The contributions of TLMPs induced by cigarette smoke to endothelial proliferation/apoptosis, autophagy and cytokine levels were also measured. Notably, the potential mechanism of autophagy and apoptosis dysfunction in endothelial cells was further examined. Cigarette smoke promoted the release of microparticles from T lymphocytes. TLMPs attenuated endothelial proliferation but promoted endothelial apoptosis/autophagy and the expression of proinflammatory cytokines, especially when T lymphocytes were preexposed to cigarette smoke. The potential mechanism may involve disorders of oxidative stress and STAT3 phosphorylation. In conclusion, cigarette smoke-exposed microparticles released from T lymphocytes contribute to autophagy and apoptosis dysfunction in pulmonary microvascular endothelial cells.

Causal Correlations Between Plasma Metabolites, Inflammatory Proteins, and Chronic Obstructive Pulmonary Disease: A Mendelian Randomization and Bioinformatics-Based Investigation

Background

An increasing number of studies have demonstrated a strong correlation between metabolism, inflammation, and chronic obstructive pulmonary disease (COPD). However, it remains unclear if there is a causal relationship between these factors. This study employed the Mendelian randomization (MR) approach to investigate the associations between these factors and explore the mediating roles of key inflammatory proteins.

Methods

MR was used to assess the causal associations between plasma metabolites, inflammatory proteins, and COPD. Sensitivity analyses were performed to verify the robustness of the findings. Mediation analysis was conducted to explore the roles of inflammatory proteins in the metabolism-COPD pathway. We constructed protein-protein interaction (PPI) network and explored the potential mechanism through gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Single-cell sequencing and transcriptome datasets were used for auxiliary validation. Finally, experimental validation was performed using human lung tissue.

Results

This study identified 63 metabolites, 10 metabolite ratios, and 48 inflammatory proteins that were associated with COPD, all of which exhibited potential causal relationships. Furthermore, three proteins were identified as mediators in the metabolite-to-COPD pathway. PPI network, GO and KEGG enrichment analysis revealed the biological pathways in which they were involved. Validation of the expression of these three intermediary proteins in lung tissue demonstrated that NRXN3 was expressed in pulmonary endothelial cells and exerted a protective effect against COPD development.

Conclusion

The MR analysis revealed causal associations among metabolism, inflammation, and COPD. These findings offer novel insights into metabolism-inflammation-COPD mechanisms, suggesting that interventions targeting metabolic processes may represent a promising strategy for preventing the onset or progression of COPD.

Extracellular vesicles in atherosclerosis: Current and forthcoming impact

Atherosclerosis is the main pathogenic substrate for cardiovascular diseases (CVDs). Initially categorized as a passive cholesterol storage disease, nowadays, it is considered an active process, identifying inflammation among the key players for its initiation and progression. Despite these advances, patients with CVDs are still at high risk of thrombotic events and death, urging to deepen into the molecular mechanisms underlying atherogenesis, and to identify novel diagnosis and prognosis biomarkers for their stratification. In this context, extracellular vesicles (EVs) have been postulated as an alternative in search of novel biomarkers in atherosclerotic diseases, as well as to investigate the crosstalk between the cells participating in the processes leading to arterial remodelling. EVs are nanosized lipidic particles released by most cell types in physiological and pathological conditions, that enclose lipids, proteins, and nucleic acids from parental cells reflecting their activation status. First considered cellular waste disposal systems, at present, EVs have been recognized as active effectors in a myriad of cellular processes, and as potential diagnosis and prognosis biomarkers also in CVDs. This review summarizes the role of EVs as potential biomarkers of CVDs, and their involvement into the processes leading to atherosclerosis.

Pathology of idiopathic pulmonary fibrosis with particular focus on vascular endothelium and epithelial injury and their therapeutic potential

Idiopathic pulmonary fibrosis (IPF) remains a challenging disease with no drugs available to change the trajectory. It is a condition associated with excessive and highly progressive scarring of the lungs with remodelling and extracellular matrix deposition. It is a highly "destructive" disease of the lungs. The diagnosis of IPF is challenging due to continuous evolution of the disease, which also makes early interventions very difficult. The role of vascular endothelial cells has not been explored in IPF in great detail. We do not know much about their contribution to arterial or vascular remodelling, extracellular matrix changes and contribution to pulmonary hypertension and lung fibrosis in general. Endothelial to mesenchymal transition appears to be central to such changes in IPF. Similarly, for epithelial changes, the process of epithelial to mesenchymal transition seem to be the key both for airway epithelial cells and type-2 pneumocytes. We focus here on endothelial and epithelial cell changes and its contributions to IPF. In this review we revisit the pathology of IPF, mechanistic signalling pathways, clinical definition, update on diagnosis and new advances made in treatment of this disease. We discuss ongoing clinical trials with mode of action. A multidisciplinary collaborative approach is needed to understand this treacherous disease for new therapeutic targets.

Extracellular Vesicles as Mediators in Atherosclerotic Cardiovascular Disease

Atherosclerosis is a chronic inflammatory disease of the arterial intima, characterized by accumulation of lipoproteins and accompanying inflammation, leading to the formation of plaques that eventually trigger occlusive thrombotic events, such as myocardial infarction and ischemic stroke. Although many aspects of plaque development have been elucidated, the role of extracellular vesicles (EVs), which are lipid bilayer-delimited vesicles released by cells as mediators of intercellular communication, has only recently come into focus of atherosclerosis research. EVs comprise several subtypes that may be differentiated by their size, mode of biogenesis, or surface marker expression and cargo. The functional effects of EVs in atherosclerosis depend on their cellular origin and the specific pathophysiological context. EVs have been suggested to play a role in all stages of plaque formation. In this review, we highlight the known mechanisms by which EVs modulate atherogenesis and outline current limitations and challenges in the field.

Surface markers on microparticles involved in obesity-derived diseases

AIMS

This review aimed to investigate the different types of microparticles playing role in obesity-related diseases. Additionally, the factors participating in changing the microparticles amount in obese people will also be discussed.

MATERIAL & METHODS

The authors collected the relevant articles published until 2023 and these are carefully selected from three scientific databases based on keywords.

KEY FINDINGS

It has been revealed that exercise might change the microparticle content in the body. The other factor which participates in obesity process is the oxidative stress which is increased in microparticles. Moreover, the obesity is implicated in metabolic conditions including diabetes and cardiovascular diseases.

SIGNIFICANCE

More than one-third of people on the planet today are known as overweight individuals. Microparticles (MPs) are small membrane-bound vesicles that are found in healthy people's blood and are elevated in patients with pathological conditions such as obesity. MPs mostly come from platelets, leukocytes, endothelial cells, and vascular smooth muscle cells. Considering the effect of obesity on microparticles, these small membrane-bound vesicles might play a crucial role in preventing or treatment of obesity.

Detection and Characterization of Extracellular Vesicles in Sputum Samples of COPD Patients

BACKGROUND

Only one study has reported the presence of extracellular vesicles (EVs) in COPD patients' sputum. Thus, we aimed to isolate and characterize EVs from COPD and healthy individuals' sputum.

METHODS

A total of 20 spontaneous sputum samples from COPD patients (m/f: 19/1) and induced sputum samples from healthy controls (m/f: 8/2) were used for EV isolation. The sputum supernatants were resuspended in PBS, precleared by centrifugation at 800× g for 10 min at 4 °C, and passed through a 0.22 μm filter (Millipore, Burlington, MA, USA). EVs were isolated by a standard membrane affinity spin column method (exoEasy maxi kit, Qiagen, Hilden, Germany). The EVs were then characterized by assessing their morphology and size using Transmission Electron Microscopy (TEM) and determining the CD9 and CD81 EV-markers with Western blot analysis.

RESULTS

The EVs had a spherical shape and their mean diameter in the COPD patients was significantly greater than in the controls. Enrichment of the EV markers, CD9 and CD81, were detected in both the healthy and COPD individuals. Total EV-associated protein was significantly increased in the COPD patients compared to the controls. ROC analysis showed that total EV-associated protein in the sputum could be used to differentiate between the controls and COPD patients, with a sensitivity of 80% and a specificity of 70% at a cut-off point of 55.59 μg/mL (AUC = 0.8150).

CONCLUSIONS

EVs were detectable in both the COPD and healthy individuals' sputum. The ratio of EVs in the 150-200 nm range was twice as high in the COPD patients than in the controls. The COPD patients' sputum contained increased total EV-associated protein as compared to controls, highlighting their value as a new source of specific exoproteins.

Pulmonary Vascular Dysfunctions in Cystic Fibrosis

Cystic fibrosis (CF) is an inherited disorder caused by a deleterious mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Given that the CFTR protein is a chloride channel expressed on a variety of cells throughout the human body, mutations in this gene impact several organs, particularly the lungs. For this very reason, research regarding CF disease and CFTR function has historically focused on the lung airway epithelium. Nevertheless, it was discovered more than two decades ago that CFTR is also expressed and functional on endothelial cells. Despite the great strides that have been made in understanding the role of CFTR in the airway epithelium, the role of CFTR in the endothelium remains unclear. Considering that the airway epithelium and endothelium work in tandem to allow gas exchange, it becomes very crucial to understand how a defective CFTR protein can impact the pulmonary vasculature and overall lung function. Fortunately, more recent research has been dedicated to elucidating the role of CFTR in the endothelium. As a result, several vascular dysfunctions associated with CF disease have come to light. Here, we summarize the current knowledge on pulmonary vascular dysfunctions in CF and discuss applicable therapies.

Vessel and Airway Characteristics in One-Year Computed Tomography-defined Rapid Emphysema Progression: SPIROMICS

Rationale: Rates of emphysema progression vary in chronic obstructive pulmonary disease (COPD), and the relationships with vascular and airway pathophysiology remain unclear. Objectives: We sought to determine if indices of peripheral (segmental and beyond) pulmonary arterial dilation measured on computed tomography (CT) are associated with a 1-year index of emphysema (EI; percentage of voxels <-950 Hounsfield units) progression. Methods: Five hundred ninety-nine former and never-smokers (Global Initiative for Chronic Obstructive Lung Disease stages 0-3) were evaluated from the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study) cohort: rapid emphysema progressors (RPs; n = 188, 1-year ΔEI > 1%), nonprogressors (n = 301, 1-year ΔEI ± 0.5%), and never-smokers (n = 110). Segmental pulmonary arterial cross-sectional areas were standardized to associated airway luminal areas (segmental pulmonary artery-to-airway ratio [PAARseg]). Full-inspiratory CT scan-derived total (arteries and veins) pulmonary vascular volume (TPVV) was compared with small vessel volume (radius smaller than 0.75 mm). Ratios of airway to lung volume (an index of dysanapsis and COPD risk) were compared with ratios of TPVV to lung volume. Results: Compared with nonprogressors, RPs exhibited significantly larger PAARseg (0.73 ± 0.29 vs. 0.67 ± 0.23; P = 0.001), lower ratios of TPVV to lung volume (3.21 ± 0.42% vs. 3.48 ± 0.38%; P = 5.0 × 10-12), lower ratios of airway to lung volume (0.031 ± 0.003 vs. 0.034 ± 0.004; P = 6.1 × 10-13), and larger ratios of small vessel volume to TPVV (37.91 ± 4.26% vs. 35.53 ± 4.89%; P = 1.9 × 10-7). In adjusted analyses, an increment of 1 standard deviation in PAARseg was associated with a 98.4% higher rate of severe exacerbations (95% confidence interval, 29-206%; P = 0.002) and 79.3% higher odds of being in the RP group (95% confidence interval, 24-157%; P = 0.001). At 2-year follow-up, the CT-defined RP group demonstrated a significant decline in postbronchodilator percentage predicted forced expiratory volume in 1 second. Conclusions: Rapid one-year progression of emphysema was associated with indices indicative of higher peripheral pulmonary vascular resistance and a possible role played by pulmonary vascular-airway dysanapsis.

Clinical Correlates of a Nonplexiform Vasculopathy in Patients With a Diagnosis of Idiopathic Pulmonary Arterial Hypertension

BACKGROUND

The clinical phenotype of patients with idiopathic pulmonary arterial hypertension (IPAH) has changed. Whether subgroups of patients with IPAH have different vascular phenotypes is a subject of debate.

RESEARCH QUESTION

What are the histologic patterns and their clinical correlates in patients with a diagnosis of IPAH or hereditary pulmonary arterial hypertension?

STUDY DESIGN AND METHODS

In this this cross-sectional registry study, lung histology of 50 patients with IPAH was assessed qualitatively by two experienced pathologists. In addition, quantitative analysis by means of histopathologic morphometry using immunohistochemistry was performed. Histopathologic characteristics were correlated with clinical and hemodynamic parameters.

RESULTS

In this cohort of 50 patients with IPAH, a plexiform vasculopathy was observed in 26 of 50 patients (52%), whereas 24 of 50 patients (48%) showed a nonplexiform vasculopathy. The nonplexiform vasculopathy was characterized by prominent pulmonary microvascular (arterioles and venules) remodeling and vascular rarefaction. Although hemodynamic parameters were comparable in plexiform vs nonplexiform vasculopathy, patients with nonplexiform vasculopathy were older, more often were male, more often had a history of cigarette smoking, and had lower diffusing capacity of the lungs for carbon monoxide at diagnosis. No mutations in established pulmonary arterial hypertension genes were found in the nonplexiform group.

INTERPRETATION

This study revealed different vascular phenotypes within the current spectrum of patients with a diagnosis of IPAH, separated by clinical characteristics (age, sex, history of cigarette smoking, and diffusing capacity of the lungs for carbon monoxide at diagnosis). Potential differences in underlying pathobiological mechanisms between patients with plexiform and nonplexiform microvascular disease should be taken into account in future research strategies unravelling the pathophysiologic features of pulmonary hypertension and developing biology-targeted treatment approaches.

Musculoskeletal crosstalk in chronic obstructive pulmonary disease and comorbidities: Emerging roles and therapeutic potentials

Chronic Obstructive Pulmonary Disease (COPD) is a multifaceted respiratory disorder characterized by progressive airflow limitation and systemic implications. It has become increasingly apparent that COPD exerts its influence far beyond the respiratory system, extending its impact to various organ systems. Among these, the musculoskeletal system emerges as a central player in both the pathogenesis and management of COPD and its associated comorbidities. Muscle dysfunction and osteoporosis are prevalent musculoskeletal disorders in COPD patients, leading to a substantial decline in exercise capacity and overall health. These manifestations are influenced by systemic inflammation, oxidative stress, and hormonal imbalances, all hallmarks of COPD. Recent research has uncovered an intricate interplay between COPD and musculoskeletal comorbidities, suggesting that muscle and bone tissues may cross-communicate through the release of signalling molecules, known as "myokines" and "osteokines". We explored this dynamic relationship, with a particular focus on the role of the immune system in mediating the cross-communication between muscle and bone in COPD. Moreover, we delved into existing and emerging therapeutic strategies for managing musculoskeletal disorders in COPD. It underscores the development of personalized treatment approaches that target both the respiratory and musculoskeletal aspects of COPD, offering the promise of improved well-being and quality of life for individuals grappling with this complex condition. This comprehensive review underscores the significance of recognizing the profound impact of COPD on the musculoskeletal system and its comorbidities. By unravelling the intricate connections between these systems and exploring innovative treatment avenues, we can aspire to enhance the overall care and outcomes for COPD patients, ultimately offering hope for improved health and well-being.

Cellular senescence in chronic lung diseases from newborns to the elderly: An update literature review

The role of cellular senescence in age-related diseases has been fully recognized. In various age-related-chronic lung diseases, the function of alveolar epithelial cells (AECs) is impaired and alveolar regeneration disorders, especially in bronchopulmonary dysplasia，pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), cancer, etc. Except for age-related-chronic lung diseases, an increasing number of studies are exploring the role of cellular senescence in developmental chronic lung diseases, which typically originate in childhood and even in the neonatal period. This review provides an overview of cellular senescence and lung diseases from newborns to the elderly, attempting to draw attention to the relationship between cellular senescence and developmental lung diseases.

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.

Channels of Communication: Extracellular Vesicles in Environmental Stress and Human Disease

Extracellular vesicles offer great promise for revealing mechanisms and serving as biomarkers in studies of exposure effects on neurological, respiratory, reproductive, and other physiological systems-and they require only a simple blood draw.

Does Chronic Obstructive Pulmonary Disease Originate from Different Cell Types?

The onset of chronic obstructive pulmonary disease (COPD) is heterogeneous, and current approaches to define distinct disease phenotypes are lacking. In addition to clinical methodologies, subtyping COPD has also been challenged by the reliance on human lung samples from late-stage diseases. Different COPD phenotypes may be initiated from the susceptibility of different cell types to cigarette smoke, environmental pollution, and infections at early stages that ultimately converge at later stages in airway remodeling and destruction of the alveoli when the disease is diagnosed. This perspective provides discussion points on how studies to date define different cell types of the lung that can initiate COPD pathogenesis, focusing on the susceptibility of macrophages, T and B cells, mast cells, dendritic cells, endothelial cells, and airway epithelial cells. Additional cell types, including fibroblasts, smooth muscle cells, neuronal cells, and other rare cell types not covered here, may also play a role in orchestrating COPD. Here, we discuss current knowledge gaps, such as which cell types drive distinct disease phenotypes and/or stages of the disease and which cells are primarily affected by the genetic variants identified by whole genome-wide association studies. Applying new technologies that interrogate the functional role of a specific cell type or a combination of cell types as well as single-cell transcriptomics and proteomic approaches are creating new opportunities to understand and clarify the pathophysiology and thereby the clinical heterogeneity of COPD.

Seminar: Extracellular Vesicles as Mediators of Environmental Stress in Human Disease

BACKGROUND

Extracellular vesicles (EVs), membrane-bound particles containing a variety of RNA types, DNA, proteins, and other macromolecules, are now appreciated as an important means of communication between cells and tissues, both in normal cellular physiology and as a potential indicator of cellular stress, environmental exposures, and early disease pathogenesis. Extracellular signaling through EVs is a growing field of research for understanding fundamental mechanisms of health and disease and for the potential for biomarker discovery and therapy development. EVs are also known to play important roles in mediating the effects of exposure to environmental stress.

OBJECTIVES

This seminar addresses the application of new tools and approaches for EV research, developed in part through the National Institutes of Health (NIH) Extracellular RNA Communication Program, and reflects presentations and discussions from a workshop held 27-28 September 2021 by the National Institute of Environmental Health Sciences (NIEHS) and the National Center for Advancing Translational Sciences (NCATS) on "Extracellular Vesicles, Exosomes, and Cell-Cell Signaling in Response to Environmental Stress." The panel of experts discussed current research on EVs and environmental exposures, highlighted recent advances in EV isolation and characterization, and considered research gaps and opportunities toward identifying and characterizing the roles for EVs in environmentally related diseases, as well as the current challenges and opportunities in this field.

DISCUSSION

The authors discuss the application of new experimental models, particularly organ-on-chip (OOC) systems and in vitro approaches and how these have the potential to extend findings in population-based studies of EVs in exposure-related diseases. Given the complex challenges of identifying cell-specific EVs related to environmental exposures, as well as the general heterogeneity and variability in EVs in blood and other accessible biological samples, there is a critical need for rigorous reporting of experimental methods and validation studies. The authors note that these efforts, combined with cross-disciplinary approaches, would ensure that future research efforts in environmental health studies on EV biomarkers are rigorous and reproducible. https://doi.org/10.1289/EHP12980.

High apoptotic endothelial microparticle levels measured in asthma with elevated IgE and eosinophils

While asthma is considered an inflammatory-mediated airway epithelial and smooth muscle disorder, there is increasing evidence of airway capillary endothelial dysfunction associated with vascular remodelling and angiogenesis in some individuals with this condition. The inflammation is typically characterized as type-2 high (eosinophilic) vs type 2-low (neutrophilic and pauci-granulocytic); we hypothesized that the type-2 high group would be more likely to evidence endothelial dysfunction. As a biomarker of these processes, we hypothesized that nonsmokers with allergic asthma may have elevated plasma levels of endothelial microparticles (EMPs), membrane vesicles that are shed when endothelial cells undergo activation or apoptosis. Total and apoptotic circulating EMPs were measured by fluorescence-activated cell analysis in patients with allergic asthma (n = 29) and control subjects (n = 26), all nonsmokers. When the entire group of patients with asthma were compared to the control subjects, there were no differences in total circulating EMPs nor apoptotic EMPs. However, patients with asthma with elevated levels of IgE and eosinophils had higher levels of apoptotic EMPs, compared to patients with asthma with mildly increased IgE and eosinophil levels. This observation is relevant to precision therapies for asthma and highlights the importance of sub-phenotyping in the condition.

Extracellular vesicles and COPD: foe or friend?

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease characterized by progressive airflow limitation. The complex biological processes of COPD include protein hydrolysis tissue remodeling, innate immune inflammation, disturbed host-pathogen response, abnormal cellular phenotype conversion, and cellular senescence. Extracellular vesicles (EVs) (including apoptotic vesicles, microvesicles and exosomes), are released by almost all cell types and can be found in a variety of body fluids including blood, sputum and urine. EVs are key mediators in cell-cell communication and can be used by using their bioactive substances (DNA, RNA, miRNA, proteins and other metabolites) to enable cells in adjacent and distant tissues to perform a wide variety of functions, which in turn affect the physiological and pathological functions of the body. Thus, EVs is expected to play an important role in the pathogenesis of COPD, which in turn affects its acute exacerbations and may serve as a diagnostic marker for it. Furthermore, recent therapeutic approaches and advances have introduced EVs into the treatment of COPD, such as the modification of EVs into novel drug delivery vehicles. Here, we discuss the role of EVs from cells of different origins in the pathogenesis of COPD and explore their possible use as biomarkers in diagnosis, and finally describe their role in therapy and future prospects for their application. Graphical Abstract.

E-Cigarette Aerosol Condensate Leads to Impaired Coronary Endothelial Cell Health and Restricted Angiogenesis

Cardiovascular disease (CVD) is a leading cause of mortality worldwide, with cigarette smoking being a major preventable risk factor. Smoking cessation can be difficult due to the addictive nature of nicotine and the withdrawal symptoms following cessation. Electronic cigarettes (e-Cigs) have emerged as an alternative smoking cessation device, which has been increasingly used by non-smokers; however, the cardiovascular effects surrounding the use of e-Cigs remains unclear. This study aimed to investigate the effects of e-Cig aerosol condensate (EAC) (0 mg and 18 mg nicotine) in vitro on human coronary artery endothelial cells (HCAEC) and in vivo on the cardiovascular system using a mouse model of ‘e-vaping’. In vitro results show a decrease in cell viability of HCAEC when exposed to EAC either directly or after exposure to conditioned lung cell media (p < 0.05 vs. control). Reactive oxygen species were increased in HCAEC when exposed to EAC directly or after exposure to conditioned lung cell media (p < 0.0001 vs. control). ICAM-1 protein expression levels were increased after exposure to conditioned lung cell media (18 mg vs. control, p < 0.01). Ex vivo results show an increase in the mRNA levels of anti-angiogenic marker, FKBPL (p < 0.05 vs. sham), and endothelial cell adhesion molecule involved in barrier function, ICAM-1 (p < 0.05 vs. sham) in murine hearts following exposure to electronic cigarette aerosol treatment containing a higher amount of nicotine. Immunohistochemistry also revealed an upregulation of FKBPL and ICAM-1 protein expression levels. This study showed that despite e-Cigs being widely used for tobacco smoking cessation, these can negatively impact endothelial cell health with a potential to lead to the development of cardiovascular disease.

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.

Impaired exercise capacity in individuals with non-obstructive small airway dysfunction

Background

Whether individuals with non-obstructive spirometry-defined small airway dysfunction (SAD) have impaired exercise capacity is unclear, particularly in never-smokers. This study clarifies the degree of impaired exercise capacity and its potential cause in individuals with non-obstructive SAD.

Methods

This community-based, multiyear cross-sectional study analyzed data collected in Guangdong, China from 2012-2019 by the National Science and Technology Support Plan Program. Measurements of exercise capacity [peak work rate and peak oxygen uptake ( V ˙ O 2peak )] in participants with non-obstructive spirometry-defined SAD (n=157) were compared with those in controls (n=85) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) I patients (n=239). Subgroup analyses were performed by smoking status.

Results

The risk of impaired exercise capacity was significantly higher in participants with non-obstructive SAD [ V ˙ O 2peak <84%predicted, adjusted odds ratio (aOR) =2.53; 95% confidence interval (CI): 1.42-4.52] than in controls but was not significantly different from that in GOLD I patients. Results were consistent within subgroups of smoking status (ever-smokers: non-obstructive SAD vs. controls, aOR =2.44; 95% CI: 1.08-5.51; never-smokers: non-obstructive SAD vs. controls, aOR =2.38, 95% CI: 1.02-5.58). Participants with non-obstructive SAD had a significantly lower peak work rate (β=-10.5; 95% CI: -16.3 to -4.7) and V ˙ O 2peak (%predicted, β=-4.0; 95% CI: -7.7 to -0.2) and tended to have higher ventilatory equivalents for carbon dioxide at the ventilatory threshold ( V ˙ E / V ˙ CO 2AT , β=1.1; 95% CI: -0.1 to 2.3) when compared with controls. Both peak work rate and V ˙ O 2peak were negatively correlated with V ˙ E / V ˙ CO 2AT .

Conclusions

Although not meeting the current criteria for chronic obstructive pulmonary disease, individuals with non-obstructive SAD have impaired exercise capacity that may be associated with ventilatory inefficiency regardless of smoking status.

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.

Prevalence of reduced lung diffusing capacity and CT scan findings in smokers without airflow limitation: a population-based study

BACKGROUND

Population distribution of reduced diffusing capacity of the lungs for carbon monoxide (DLCO) in smokers and main consequences are not properly recognised. The objectives of this study were to describe the prevalence of reduced DLCO in a population-based sample of current and former smoker subjects without airflow limitation and to describe its morphological, functional and clinical implications.

METHODS

A sample of 405 subjects aged 40 years or older with postbronchodilator forced expiratory volume in 1 s/forced vital capacity (FVC) >0.70 was obtained from a random population-based sample of 9092 subjects evaluated in the EPISCAN II study. Baseline evaluation included clinical questionnaires, exhaled carbon monoxide (CO) measurement, spirometry, DLCO determination, 6 min walk test, routine blood analysis and low-dose CT scan with evaluation of lung density and airway wall thickness.

RESULTS

In never, former and current smokers, prevalence of reduced DLCO was 6.7%, 14.4% and 26.7%, respectively. Current and former smokers with reduced DLCO without airflow limitation were younger than the subjects with normal DLCO, and they had greater levels of dyspnoea and exhaled CO, greater pulmonary artery diameter and lower spirometric parameters, 6 min walk distance, daily physical activity and plasma albumin levels (all p<0.05), with no significant differences in other chronic respiratory symptoms or CT findings. FVC and exhaled CO were identified as independent risk factors for low DLCO.

CONCLUSION

Reduced DLCO is a frequent disorder among smokers without airflow limitation, associated with decreased exercise capacity and with CT findings suggesting that it may be a marker of smoking-induced early vascular damage.

TRIAL REGISTRATION NUMBER

NCT03028207.

Extracellular Vesicle-Encapsulated microRNAs as Novel Biomarkers of Lung Health

Rationale: Early detection of respiratory diseases is critical to facilitate delivery of disease-modifying interventions. Extracellular vesicle-enriched microRNAs (EV-miRNAs) may represent reliable markers of early lung injury. Objectives: Evaluate associations of plasma EV-miRNAs with lung function. Methods: The prospective NAS (Normative Aging Study) collected plasma EV-miRNA measurements from 1996-2015 and spirometry every 3-5 years through 2019. Associations of EV-miRNAs with baseline lung function were modeled using linear regression. To complement the individual miRNA approach, unsupervised machine learning was used to identify clusters of participants with distinct EV-miRNA profiles. Associations of EV-miRNA profiles with multivariate latent longitudinal lung function trajectories were modeled using log binomial regression. Biological functions of significant EV-miRNAs were explored using pathway analyses. Results were replicated in an independent sample of NAS participants and in the HEALS (Health Effects of Arsenic Longitudinal Study). Measurements and Main Results: In the main cohort of 656 participants, 51 plasma EV-miRNAs were associated with baseline lung function (false discovery rate-adjusted P value < 0.05), 28 of which were replicated in the independent NAS sample and/or in the HEALS cohort. A subset of participants with distinct EV-miRNA expression patterns had increased risk of declining lung function over time, which was replicated in the independent NAS sample. Significant EV-miRNAs were shown in pathway analyses to target biological pathways that regulate respiratory cellular immunity, the lung inflammatory response, and airway structural integrity. Conclusions: Plasma EV-miRNAs may represent a robust biomarker of subclinical lung injury and may facilitate early identification and treatment of patients at risk of developing overt lung disease.

Extracellular Vesicles' Role in the Pathophysiology and as Biomarkers in Cystic Fibrosis and COPD

In keeping with the extraordinary interest and advancement of extracellular vesicles (EVs) in pathogenesis and diagnosis fields, we herein present an update to the knowledge about their role in cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD). Although CF and COPD stem from a different origin, one genetic and the other acquired, they share a similar pathophysiology, being the CF transmembrane conductance regulator (CFTR) protein implied in both disorders. Various subsets of EVs, comprised mainly of microvesicles (MVs) and exosomes (EXOs), are secreted by various cell types that are either resident or attracted in the airways during the onset and progression of CF and COPD lung disease, representing a vehicle for metabolites, proteins and RNAs (especially microRNAs), that in turn lead to events as such neutrophil influx, the overwhelming of proteases (elastase, metalloproteases), oxidative stress, myofibroblast activation and collagen deposition. Eventually, all of these pathomechanisms lead to chronic inflammation, mucus overproduction, remodeling of the airways, and fibrosis, thus operating a complex interplay among cells and tissues. The detection of MVs and EXOs in blood and biological fluids coming from the airways (bronchoalveolar lavage fluid and sputum) allows the consideration of EVs and their cargoes as promising biomarkers for CF and COPD, although clinical expectations have yet to be fulfilled.

Identification of exercise-regulated genes in mice exposed to cigarette smoke

Cigarette smoke (CS) is the major risk factor for COPD and is linked to cardiopulmonary dysfunction. Exercise training as part of pulmonary rehabilitation is recommended for all COPD patients. It has several physiological benefits, but the mechanisms involved remain poorly defined. Here, we employed transcriptomic profiling and examined lung endothelium to investigate novel interactions between exercise and CS on cardiopulmonary alterations. Mice were exposed to 20 weeks of CS, CS + 6 weeks of high-intensity interval training on a treadmill, or control. Lung and cardiac (left and right ventricle) tissue were harvested and RNA-sequencing was performed and validated with RT-qPCR. Immunohistochemistry assessed pulmonary arteriolar changes. Transcriptome analysis between groups revealed 37 significantly regulated genes in the lung, 21 genes in the left ventricle, and 43 genes in the right ventricle (likelihood-ratio test). Validated genes that showed interaction between exercise and CS included angiotensinogen (p = 0.002) and resistin-like alpha (p = 0.019) in left ventricle, with prostacyclin synthetase different in pulmonary arterioles (p = 0.004). Transcriptomic profiling revealed changes in pulmonary and cardiac tissue following exposure to CS, with exercise training exerting rescue effects. Exercise-regulated genes included angiotensinogen and resistin-like alpha, however, it remains unclear if these represent potential candidate genes or biomarkers that could play a role during pulmonary rehabilitation.

Therapeutic use of calpeptin in COVID-19 infection

This perspective considers the benefits of the potential future use of the cell permeant calpain inhibitor, calpeptin, as a drug to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Recent work has reported calpeptin’s capacity to inhibit entry of the virus into cells. Elsewhere, several drugs, including calpeptin, were found to be able to inhibit extracellular vesicle (EV) biogenesis. Unsurprisingly, because of similarities between viral and EV release mechanisms, calpeptin has also been shown to inhibit viral egress. This approach, identifying calpeptin, through large-scale screening studies as a candidate drug to treat COVID-19, however, has not considered the longer term likely benefits of calpain inhibition, post-COVID-19. This perspective will reflect on the capacity of calpeptin for treating long COVID by inhibiting the overproduction of neutrophil extracellular traps potentially damaging lung cells and promoting clotting, together with limiting associated chronic inflammation, tissue damage and pulmonary fibrosis. It will also reflect on the tolerated and detrimental in vivo side-effects of calpain inhibition from various preclinical studies.

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.

The Emerging Role of Extracellular Vesicles Detected in Different Biological Fluids in COPD

The pathogenesis of chronic obstructive pulmonary disease (COPD) is characterized by complex cellular and molecular mechanisms, not fully elucidated so far. It involves inflammatory cells (monocytes/macrophages, neutrophils, lymphocytes), cytokines, chemokines and, probably, new players yet to be clearly identified and described. Chronic local and systemic inflammation, lung aging and cellular senescence are key pathological events in COPD development and progression over time. Extracellular vesicles (EVs), released by virtually all cells both as microvesicles and exosomes into different biological fluids, are involved in intercellular communication and, therefore, represent intriguing players in pathobiological mechanisms (including those characterizing aging and chronic diseases); moreover, the role of EVs as biomarkers in different diseases, including COPD, is rapidly gaining recognition. In this review, after recalling the essential steps of COPD pathogenesis, we summarize the current evidence on the roles of EVs collected in different biological mediums as biomarkers in COPD and as potential players in the specific mechanisms leading to disease development. We will also briefly review the data on EV as potential therapeutic targets and potential therapeutic agents.

PECAM EMPs regulate apoptosis in pulmonary microvascular endothelial cells in COPD by activating the Akt signaling pathway

INTRODUCTION

Endothelial microparticles (EMPs) are partly associated with the progress of chronic obstructive pulmonary disease (COPD). We sought to measure the levels of EMPs in COPD patients and in human pulmonary microvascular endothelial cells (HPMECs) exposed to cigarette smoking extract (CSE) to elucidate the potential mechanisms of their action.

METHODS

We obtained prospectively blood EMPs from 30 stable COPD patients and 20 non-COPD volunteers. EMP subpopulations were determined by flow cytometry in platelet-free plasma according to the expression of membrane specific antigens. Cell growth, proliferation, apoptosis and the expression of protein kinase B (Akt) in HPMECs after exposure to PECAM EMPs were assessed. After intervention with an antioxidant (Eukarion-134, EUK-134), apoptosis and the expression of Akt in HPMECs were also measured.

RESULTS

Unlike those of MCAM EMPs, VE-cadherin, PECAM and E-selectin EMP values were significantly higher in the stable COPD patients than in the non-COPD volunteers (p<0.05). Only PECAM EMPs were higher in HPMECs exposed to CSE (p<0.05). Further, in vitro studies showed that the apoptosis rate and expression of cleaved caspase 3/9 in HPMECs increased in a dose- and time-independent manner with PECAM EMPs. The expression of phospho-Akt (p-Akt) decreased in a time-independent manner with PECAM EMPs (p<0.05). Compared with the control group, the early apoptosis rate of HPMECs was higher, and the expression of p-Akt was lower in both the PECAM EMP group and EUK-134 + PECAM EMP group (p<0.05). The apoptosis rate declined markedly, and the expression of p-Akt was higher in the EUK-134 + PECAM EMP group, compared with the PECAM EMPs group (p<0.05).

CONCLUSIONS

The present results suggest that PECAM EMPs positively regulate apoptosis in HPMECs in COPD, likely by decreasing Akt phosphorylation and can be protected by antioxidants.

The Role of Cell Derived Microparticles in Cardiovascular Diseases: Current Concepts

Abstract:

Cardiovascular disease remains the main cause of human morbidity and mortality in the developed countries. Microparticles (MPs) are small vesicles originating from the cell membrane as a result of various stimuli and particularly of biological processes that constitute the pathophysiology of atherosclerosis, such as endothelial damage. They form vesicles that can transfer various molecules and signals to remote target cells without direct cell to cell interaction. Circulating microparticles have been associated with cardiovascular diseases. Therefore, many studies have been designed to further investigate the role of microparticles as biomarkers for diagnosis, prognosis, and disease monitoring. To this concept the pro-thrombotic and atherogenic potential of platelets and endothelial derived MPs has gain research interest especially concerning accelerate atherosclerosis and acute coronary syndrome triggering and prognosis. MPs especially of endothelial origin have been investigated in different clinical scenarios of heart failure and in association of left ventricular loading conditions. Finally, most cardiovascular risk factors present unique patterns of circulating MPs population, highlighting their pathophysiologic link to cardiovascular disease progression. In this review article we present a synopsis of the biogenesis and characteristics of microparticles, as well as the most recent data concerning their implication in the cardiovascular settings.

Different Contribution of Monocyte- and Platelet-Derived Microvesicles to Endothelial Behavior

Several contributions of circulating microvesicles (MVs) to the endothelial dysfunction have been reported in the past; a head-to-head comparison of platelet- and monocyte–derived MVs has however never been performed. To this aim, we assessed the involvement of these MVs in vessel damage related processes, i.e., oxidative stress, inflammation, and leukocyte-endothelial adhesion. Platelets and monocytes isolated from healthy subjects (HS, n = 15) were stimulated with TRAP-6 and LPS to release MVs that were added to human vascular endothelial cell (hECV) culture to evaluate superoxide anion production, inflammatory markers (IL-6, TNFα, NF-κB mRNA expression), and hECV adhesiveness. The effects of the MVs-induced from HS were compared to those induced by MVs spontaneously released from cells of patients with ST-segment elevation myocardial infarction (STEMI, n = 7). MVs released by HS-activated cells triggered a threefold increase in oxidative burst in a concentration-dependent manner. Only MVs released from monocytes doubled IL-6, TNFα, and NF-κB mRNA expression and monocyte-endothelial adhesion. Interestingly, the effects of the MVs isolated from STEMI-monocytes were not superimposable to previous ones except for adhesion to hECV. Conversely, MVs released from STEMI-platelets sustained both redox state and inflammatory phenotype. These data provide evidence that MVs released from activated and/or pathologic platelets and monocytes differently affect endothelial behavior, highlighting platelet-MVs as causative factors of impaired endothelial function in the acute phase of STEMI.

Extracellular vesicles and chronic obstructive pulmonary disease (COPD): a systematic review

Background

Chronic Obstructive Pulmonary Disease (COPD) is a common inflammatory disease of the airways characterized by irreversible airflow limitation, ranking the third highest cause of death worldwide. Extracellular vesicles (EVs) are important intercellular communication mediators released by cells into their extracellular environment with the capacity to transfer biological signals. EVs involved in COPD hold great potential to understand disease pathogenesis and identify important biomarkers. This systematic review aims to examine all available research on EVs in the pathogenesis and diagnosis of COPD to identify existing knowledge and support further research within the field.

Methods

Publications were searched using PubMed and EMBASE with the search terms (Exosomes or extracellular vesicles or microvesicles or microparticles or ectosomes) AND (chronic obstructive pulmonary disease or COPD or emphysema or bronchitis).

Results

Initial search yielded 512 papers of which 142 were manually selected for review and 43 were eligible for analyses. The studies were divided into groups according to the role of EVs in pathogenesis, EV origin and cargo, their role in COPD exacerbations and their diagnostic utility. EVs were found to be involved in the mechanism of pathogenesis of COPD, derived from various cell types, as well as containing modified levels of miRNAs. EVs also varied according to the pathophysiological status of disease, therefore presenting a possible method for COPD diagnosis and progress monitoring.

Conclusion

The current findings show the limited but good quality research looking at the role of EVs in COPD, demonstrating the need for more studies to better define and provide further insight into the functional characteristics of EV in COPD pathogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01984-0.

Procoagulant Microvesicles in COVID-19 Patients: Possible Modulators of Inflammation and Prothrombotic Tendency

Background

The hypercoagulability and thrombotic tendency in coronavirus disease 2019 (COVID-19) is multifactorial, driven mainly by inflammation, and endothelial dysfunction. Elevated levels of procoagulant microvesicles (MVs) and tissue factor–bearing microvesicles (TF-bearing MVs) have been observed in many diseases with thrombotic tendency. The current study aimed to measure the levels of procoagulant MVs and TF-bearing MVs in patients with COVID-19 and healthy controls and to correlate their levels with platelet counts, D-Dimer levels, and other proposed calculated inflammatory markers.

Materials and Methods

Forty ICU-admitted patients with COVID-19 and 37 healthy controls were recruited in the study. Levels of procoagulant MVs and TF-bearing MVs in the plasma of the study population were measured using enzyme linked immunosorbent assay.

Results

COVID-19 patients had significantly elevated levels of procoagulant MVs and TF-bearing MVs as compared with healthy controls (P<0.001). Procoagulant MVs significantly correlated with TF-bearing MVs, D-dimer levels, and platelet count, but not with calculated inflammatory markers (neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and platelet/neutrophil ratio).

Conclusion

Elevated levels of procoagulant MVs and TF-bearing MVs in patients with COVID-19 are suggested to be (i) early potential markers to predict the severity of COVID-19 (ii) a novel circulatory biomarker to evaluate the procoagulant activity and severity of COVID-19.

A Novel, Cell-Free Therapy to Enter Our Hearts: The Potential Role of Small EVs in Prevention and Treatment of CVD

Heart disease constitutes one of the leading causes of morbidity and mortality worldwide. Current therapeutic techniques, such as interventional revascularization, although lifesaving, come along with myocardial injury related to the reperfusion itself, called ischemia-reperfusion injury, which is an added factor for increased morbidity. For that reason, there is an imperative need for novel therapies to be developed that would either prevent or treat myocardial injury. Extracellular vesicles (EVs), specifically small EVs (sEVs), have proven to be important mediators of intercellular communication. The fact that they carry information reflecting that of the parental cell makes them an ideal candidate for diagnostic purposes. sEVs derived from immunoregulatory cells, such as mesenchymal stem cells or cardiac progenitor cells, could also be used therapeutically to exert the primary immunomodulatory function but without carrying the side effects related to cell therapy. Furthermore, as a natural product, they have the added advantage of low immunogenicity, offering the potential for safe drug delivery. In the field of cardiology, there has been great interest in the therapeutic and diagnostic potential of sEVs with significant translational potential. Here, we review the potential use of sEVs in the context of myocardial ischemia and ischemia-reperfusion injury.

Pre-chronic obstructive pulmonary disease: a pathophysiologic process or an opinion term?

PURPOSE OF REVIEW

Current guidelines does not include current or former smokers who do not have spirometric airflow limitation in their diagnostic or therapeutic algorithms for chronic obstructive pulmonary disease (COPD). The purpose of this review is to outline the burden of respiratory morbidity in this population and to discuss the potential utility of their classification as pre-COPD.

RECENT FINDINGS

It is increasingly clear that patients with a history of exposure to cigarette smoke or other environmental pollutants may have substantial lung pathology and respiratory impairment even in the absence of airflow limitation, as detected by spirometry. Not all of these patients will develop airflow limitation, but many will have considerable respiratory morbidity and a comparable prognosis to those with classical, spirometrically defined COPD. The use of the term pre-COPD may allow for the identification of these individuals in order to target preventive and earlier therapeutic strategies.

SUMMARY

Spirometry is not adequately sensitive to identify many current and former smokers and other exposed populations with significant lung pathology and respiratory symptoms. Though the pathologic processes present in these patients differ, the earlier identification of this pre-COPD population may foster the development of more effective and disease-modifying treatments.

Angiogenic content of microparticles in patients with diabetes and coronary artery disease predicts networks of endothelial dysfunction

BACKGROUND

Elevated endothelial microparticles (EMPs) levels are surrogate markers of vascular dysfunction. We analyzed EMPs with apoptotic characteristics and assessed the angiogenic contents of microparticles in the blood of patients with type 2 diabetes (T2D) according to the presence of coronary artery disease (CAD).

METHODS

A total of 80 participants were recruited and equally classified as (1) healthy without T2D, (2) T2D without cardiovascular complications, (3) T2D and chronic coronary artery disease (CAD), and (4) T2D and acute coronary syndrome (ACS). MPs were isolated from the peripheral circulation, and EMPs were characterized using flow cytometry of CD42 and CD31. CD62E was used to determine EMPs' apoptotic/activation state. MPs content was extracted and profiled using an angiogenesis array.

RESULTS

Levels of CD42- CD31 + EMPs were significantly increased in T2D with ACS (257.5 ± 35.58) when compared to healthy subjects (105.7 ± 12.96, p < 0.01). There was no significant difference when comparing T2D with and without chronic CAD. The ratio of CD42-CD62 +/CD42-CD31 + EMPs was reduced in all T2D patients, with further reduction in ACS when compared to chronic CAD, reflecting a release by apoptotic endothelial cells. The angiogenic content of the full population of MPs was analyzed. It revealed a significant differential expression of 5 factors in patients with ACS and diabetes, including TGF-β1, PD-ECGF, platelet factor 4, serpin E1, and thrombospondin 1. Ingenuity Pathway Analysis revealed that those five differentially expressed molecules, mainly TGF-β1, inhibit key pathways involved in normal endothelial function. Further comparison of the three diabetes groups to healthy controls and diabetes without cardiovascular disease to diabetes with CAD identified networks that inhibit normal endothelial cell function. Interestingly, DDP-IV was the only differentially expressed protein between chronic CAD and ACS in patients with diabetes.

CONCLUSION

Our data showed that the release of apoptosis-induced EMPs is increased in diabetes, irrespective of CAD, ACS patients having the highest levels. The protein contents of MPs interact in networks that indicate vascular dysfunction.

Mechanism by which Huoxue Tongluo Qiwei Decoction improves the erectile function of rats with diabetic erectile dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Huoxue Tongluo Qiwei Decoction is a classical herbal formula, which can improve the symptoms of erectile dysfunction (ED) patients and has a good therapeutic effect on patients with diabetic erectile dysfunction (DIED). The main function of Huoxue Tongluo Qiwei Decoction is to stimulate the blood circulation and dredge collaterals, remove blood stasis, and calm wind.

RATIONALE

To further explore the mechanism of Huoxue Tongluo Qiwei Decoction in the treatment of DIED, related animal experiments were designed.

MATERIALS AND METHODS

The chemical constituents of Huoxue Tongluo Qiwei Decoction were identified with the help of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). A rat model was induced by streptozotocin (STZ) and screened by apomorphine (APO). Serum sE-selectin, lysyl oxidase-1 (LOX-1), malondialdehyde (MDA) and other markers of vascular endothelial injury and related indicators of oxidative stress were studied through enzyme-linked immunosorbent assay (ELISA). The endothelial cells and ultrastructure of the corpus cavernosum were examined by electron microscopy and HE staining. The expression of protein and mRNA was detected by western blotting (WB) and real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

The results of the study revealed that the sE-selectin, LOX-1, intercellular adhesion molecule-1 (sICAM-1), endothelial microparticles (EMPs), P-selectin (CD62P), and MDA levels in the serum of group M rats were considerably higher than rats of group K, while the superoxide dismutase (SOD) level showed a significant decrease. In addition, the PKC pathway was activated, and the expression of related proteins and mRNA was increased. After 8 weeks of intervention with Huoxue Tongluo Qiwei Decoction and LY333531, serum level of sE-selectin, LOX-1, sICAM-1, EMPs, CD62P and MDA in L, D and G groups were remarkably lower than group M while SOD level increased significantly, protein kinase C (PKC) pathway was inhibited with the improved erectile function of rats.

CONCLUSION

Huoxue Tongluo Qiwei Decoction can inhibit the expression of protein and mRNA of the PKCβ signaling pathway related molecules in DIED rats to cure the injury of vascular endothelial, enhance antioxidant capacity, and prevent the activation of platelet, thus improving erectile function in rats with DIED.

Role of Extracellular Vesicles as Potential Diagnostic and/or Therapeutic Biomarkers in Chronic Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the first cause of death worldwide. In recent years, there has been great interest in the analysis of extracellular vesicles (EVs), including exosomes and microparticles, as potential mediators of biological communication between circulating cells/plasma and cells of the vasculature. Besides their activity as biological effectors, EVs have been also investigated as circulating/systemic biomarkers in different acute and chronic CVDs. In this review, the role of EVs as potential diagnostic and prognostic biomarkers in chronic cardiovascular diseases, including atherosclerosis (mainly, peripheral arterial disease, PAD), aortic stenosis (AS) and aortic aneurysms (AAs), will be described. Mechanistically, we will analyze the implication of EVs in pathological processes associated to cardiovascular remodeling, with special emphasis in their role in vascular and valvular calcification. Specifically, we will focus on the participation of EVs in calcium accumulation in the pathological vascular wall and aortic valves, involving the phenotypic change of vascular smooth muscle cells (SMCs) or valvular interstitial cells (IC) to osteoblast-like cells. The knowledge of the implication of EVs in the pathogenic mechanisms of cardiovascular remodeling is still to be completely deciphered but there are promising results supporting their potential translational application to the diagnosis and therapy of different CVDs.

Isolation of Primary Mouse Pulmonary Microvascular Endothelial Cells and Generation of an Immortalized Cell Line to Obtain Sufficient Extracellular Vesicles

Pulmonary microvascular endothelial cells (PMECs) and the extracellular vesicles (EVs) derived from PMECs participate in maintaining pulmonary homeostasis and mediating the inflammatory response. However, obtaining a high-purity population of PMECs and their EVs from mouse is still notoriously difficult. Herein we provide a method to isolate primary mouse PMECs (pMPMECs) and to transduce SV40 lentivirus into pMPMECs to establish an immortalized cell line (iMPMECs), which provides sufficient quantities of EVs for further studies. pMPMECs and iMPMECs can be identified using morphologic criteria, a phenotypic expression profile (e.g., CD31, CD144, G. simplicifolia lectin binding), and functional properties (e.g., Dil-acetylated low-density protein uptake, Matrigel angiogenesis). Furthermore, pMPMEC-EVs and iMPMEC-EVs can be identified and compared. The characteristics of pMPMEC-EVs and iMPMEC-EVs are ascertained by transmission electron microscopy, nanoparticle tracking analysis, and specific protein markers. iMPMECs produce far more EVs than pMPMECs, while their particle size distribution is similar. Our detailed protocol to isolate and immortalize MPMECs will provide researchers with an in vitro model to investigate the specific roles of EVs in pulmonary physiology and diseases.

Subclinical markers of cardiovascular toxicity of benzene inhalation in mice

Benzene is a ubiquitous environmental pollutant. Recent population-based studies suggest that benzene exposure is associated with an increased risk for cardiovascular disease. However, it is unclear whether benzene exposure by itself is sufficient to induce cardiovascular toxicity. We examined the effects of benzene inhalation (50 ppm, 6 h/day, 5 days/week, 6 weeks) or HEPA-filtered air exposure on the biomarkers of cardiovascular toxicity in male C57BL/6J mice. Benzene inhalation significantly increased the biomarkers of endothelial activation and injury including endothelial microparticles, activated endothelial microparticles, endothelial progenitor cell microparticles, lung endothelial microparticles, and activated lung and endothelial microparticles while having no effect on circulating levels of endothelial adhesion molecules, endothelial selectins, and biomarkers of angiogenesis. To understand how benzene may induce endothelial injury, we exposed human aortic endothelial cells to benzene metabolites. Of the metabolites tested, trans,trans-mucondialdehyde (10 μM, 18h) was the most toxic. It induced caspases-3, -7 and -9 (intrinsic pathway) activation and enhanced microparticle formation by 2.4-fold. Levels of platelet-leukocyte aggregates, platelet macroparticles, and a proportion of CD4+ and CD8+ T-cells were also significantly elevated in the blood of the benzene-exposed mice. We also found that benzene exposure increased the transcription of genes associated with endothelial cell and platelet activation in the liver; and induced inflammatory genes and suppressed cytochrome P450s in the lungs and the liver. Together, these data suggest that benzene exposure induces endothelial injury, enhances platelet activation and inflammatory processes; and circulatory levels of endothelial cell and platelet-derived microparticles and platelet-leukocyte aggregates are excellent biomarkers of cardiovascular toxicity of benzene.

Distinct Exosomal miRNA Profiles from BALF and Lung Tissue of COPD and IPF Patients

Chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) are chronic, progressive lung ailments that are characterized by distinct pathologies. Early detection biomarkers and disease mechanisms for these debilitating diseases are lacking. Extracellular vesicles (EVs), including exosomes, are small, lipid-bound vesicles attributed to carry proteins, lipids, and RNA molecules to facilitate cell-to-cell communication under normal and diseased conditions. Exosomal miRNAs have been studied in relation to many diseases. However, there is little to no knowledge regarding the miRNA population of bronchoalveolar lavage fluid (BALF) or the lung-tissue-derived exosomes in COPD and IPF. Here, we determined and compared the miRNA profiles of BALF- and lung-tissue-derived exosomes of healthy non-smokers, smokers, and patients with COPD or IPF in independent cohorts. Results: Exosome characterization using NanoSight particle tracking and TEM demonstrated that the BALF-derived exosomes were ~89.85 nm in size with a yield of ~2.95 × 10¹⁰ particles/mL in concentration. Lung-derived exosomes were larger in size (~146.04 nm) with a higher yield of ~2.38 × 10¹¹ particles/mL. NGS results identified three differentially expressed miRNAs in the BALF, while there was one in the lung-derived exosomes from COPD patients as compared to healthy non-smokers. Of these, miR-122-5p was three- or five-fold downregulated among the lung-tissue-derived exosomes of COPD patients as compared to healthy non-smokers and smokers, respectively. Interestingly, there were a large number (55) of differentially expressed miRNAs in the lung-tissue-derived exosomes of IPF patients compared to non-smoking controls. Conclusions: Overall, we identified lung-specific miRNAs associated with chronic lung diseases that can serve as potential biomarkers or therapeutic targets.

Epithelial-Cell-Derived Extracellular Vesicles in Pathophysiology of Epithelial Injury and Repair in Chronic Rhinosinusitis: Connecting Immunology in Research Lab to Biomarkers in Clinics

Epithelial barrier disruption and failure of epithelial repair by aberrant epithelial-mesenchymal transition (EMT)-induced basal cells observed in nasal mucosa of chronic rhinosinusitis (CRS) are speculated to play important roles in disease pathophysiology. Microparticles (MPs) are a type of extracellular vesicle (EV) released by budding or shedding from the plasma membrane of activated or apoptotic cells. MPs are detected in nasal lavage fluids (NLFs) and are now receiving attention as potential biomarkers to evaluate the degree of activation of immune cells and injury of structural cells in nasal mucosa of subjects with sinus disease. There are three types of epithelial-cell-derived MPs, which are defined by the expression of different epithelial specific markers on their surface: EpCAM, E-cadherin, and integrin β6 (ITGB6). When these markers are on MPs that are also carrying canonical EMT/mesenchymal markers (Snail (SNAI1); Slug (SNAI2); alpha-smooth muscle actin (αSMA, ACTA2)) or pro- and anti-coagulant molecules (tissue factor (TF); tissue plasminogen activator (tPA); plasminogen activator inhibitor-1 (PAI-1)), they provide insight as to the roles of epithelial activation for EMT or regulation of coagulation in the underlying disease. In this review, we discuss the potential of epithelial MPs as research tools to evaluate status of nasal mucosae of CRS patients in the lab, as well as biomarkers for management and treatment of CRS in the clinic.

Role of extracellular vesicles in atherosclerosis: An update

Extracellular vesicles (EVs) are membrane particles released by most cell types in response to different stimuli. They are composed of a lipid bilayer that encloses a wide range of bioactive material, including proteins and nucleic acids. EVs have garnered increasing attention over recent years, as their role in intercellular communication has been brought to light. As such, they have been found to regulate pathophysiologic pathways like inflammation, angiogenesis, or senescence, and are therefore implicated in key aspects atherosclerosis initiation and progression. Interestingly, EVs appear to have a multifaceted role; depending on their cargo, they can either facilitate or hamper the development of atherosclerotic lesions. In this review, we examine how EVs of varying origins may be implicated in the different phases of atherosclerotic lesion development. We also discuss the need to standardize isolation and analysis procedures to fully fulfil their potential as biomarkers and therapeutics for cardiovascular diseases.

Association of Systemic Endothelial-Derived and Platelet-Derived Microparticles With Clinical Outcomes in Chronic Obstructive Pulmonary Disease

PURPOSE

Endothelial and platelet microparticles (eMPs and pMPs), markers of cellular activation, dysfunction, or apoptosis, have been associated with multiple cardiovascular conditions. Chronic obstructive pulmonary disease (COPD) is associated with cardiovascular comorbidities and platelet/endothelial dysfunction. We analyzed whether eMPs and pMPs are associated with COPD status and/or severity.

PATIENTS AND METHODS

A total of 58 COPD patients and 19 controls were enrolled and followed for an average of 1.17 years. Characterization of COPD included lung function, Body mass index-airflow Obstruction-Dyspnea-Exercise (BODE) scores, health-related quality of life, exacerbations, comorbidities, and mortality. Plasma collection to measure eMPs and pMPs via flow cytometry was performed at enrollment as well as during acute exacerbation in 17 participants. We measured pMPs (CD31+, CD41+31+, CD 62P+), eMPs (ULEX lectin+, CD51+, CD54+, CD62E+), the apoptotic CD62E+/CD31+ ratio, and Annexin V MP.

RESULTS

As a group, COPD participants had no difference in all MP levels studied compared with controls. No significant correlations with diffusion capacity for carbon monoxide, quality of life, and exacerbation status were found in all MPs studied. However, the eMP ULEX and the pMP CD 62P+ were higher among COPD Global initiative for chronic Obstructive Lung Disease (GOLD) stage 3 patients compared to controls. The CD62E+/CD31+ ratio was lower in controls and GOLD stage 1 COPD participants compared with GOLD stage 2/3 COPD participants, suggesting increased apoptosis. eMP ULEX lectin+ decreased during acute exacerbations and pMP41+31+ significantly increased as BODE score increased.

CONCLUSIONS

After adjusting for comorbidities, most eMPs and pMPs studied do not correlate significantly with COPD status or severity.

Extracellular vesicles in atherothrombosis and cardiovascular disease: Friends and foes

Extracellular vesicles (EV, exosomes and microvesicles -MV-) are 30-1000 nm particles surrounded by a phospholipid bilayer membrane that are released from almost all cell types through several pathways. EV encapsulate bioactive molecules, and the molecular cargo is determined by the trigger stimulating its release, reflecting its cell origin and biological functions. This review is primarily focused on the latest evidence of the roles of EV, released from cells involved in the different stages of atherothrombosis. The potential translation of this information to the clinical arena is also discussed. EV can have both pro- and anti-atherothrombotic effects depending on several factors, such as the type of vesicle (MV/exosome), its molecular cargo, its cell of origin, and the context in which are generated, i.e., the stimulus triggering its release. In fact, EV actively participate in every step of atherosclerosis onset and progression, and also in thrombus formation leading to a major adverse cardiovascular event. Moreover, EV have a determinant role in fibrous cap stability, thus determining the propensity of the plaque to rupture. On the other hand, and again, conditioned by the context and stimulus instigating its secretion, some EV may have protective biological functions, perhaps as a compensatory mechanism or even with reparative or regenerative potential. Therefore, the study of the implication of EV in atherothrombosis might be of relevance to unveil new therapeutic targets, vectors and biomarkers of cardiovascular disease (CVD).

Unravelling the mechanisms driving multimorbidity in COPD to develop holistic approaches to patient-centred care

COPD is a major cause of morbidity and mortality worldwide. Multimorbidity is common in COPD patients and a key modifiable factor, which requires timely identification and targeted holistic management strategies to improve outcomes and reduce the burden of disease.We discuss the use of integrative approaches, such as cluster analysis and network-based theory, to understand the common and novel pathobiological mechanisms underlying COPD and comorbid disease, which are likely to be key to informing new management strategies.Furthermore, we discuss the current understanding of mechanistic drivers to multimorbidity in COPD, including hypotheses such as multimorbidity as a result of shared common exposure to noxious stimuli (e.g. tobacco smoke), or as a consequence of loss of function following the development of pulmonary disease. In addition, we explore the links to pulmonary disease processes such as systemic overspill of pulmonary inflammation, immune cell priming within the inflamed COPD lung and targeted messengers such as extracellular vesicles as a result of local damage as a cause for multimorbidity in COPD.Finally, we focus on current and new management strategies which may target these underlying mechanisms, with the aim of holistic, patient-centred treatment rather than single disease management.

Microparticles in COVID-19 as a link between lung injury extension and thrombosis

Among the distinctive features of coronavirus disease 2019 (COVID-19), numerous reports have stressed the importance of vascular damage associated with coagulopathy onset [1]. Histological analysis of pulmonary vessels in patients with COVID-19 revealed severe endothelial injury associated with intracellular severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus and disrupted endothelial cell membranes together with widespread thrombosis and occlusion of alveolar capillaries. Microparticles (MPs) shed by apoptotic/stimulated cells of various cellular lineages, including platelets, leukocytes, macrophages or endothelial cells, are reliable markers of vascular damage [2] released upon pro-inflammatory conditions and behave as active participants in the early steps of clot formation [3]. Circulating MPs promote procoagulant responses due to the exposure of tissue factor, the physiological activator of the coagulation cascade, and of negatively charged phospholipids, such as phosphatidylserine, required for the assembly of the tenase and prothrombinase coagulation complexes ultimately leading to thrombin generation, through which they can precisely be quantified [4]. MPs carry angiotensin-converting enzyme (ACE)1 and upregulate ACE1 expression in neighbouring endothelial cells [5]. By contrast, exosomes were recently reported to convey ACE2, the cell-entry receptor for SARS-CoV-2 [4], in the vasculature [6]. ACE2 converts angiotensin II (Ang II) into angiotensin 1–7 (Ang 1–7), which by virtue of its actions on the Mas receptor, limits the noxious effects of Ang II. Pioneering data have demonstrated that the renin–angiotensin system has a crucial role in severe acute injury and that ACE2 has a protective role in acute lung injury mediated by SARS-CoV [7]. According to this paradigm, the loss of ACE2 function following binding by SARS-CoV-2 may contribute to unopposed Ang II accumulation that further exacerbates tissue injury and promotes inflammation, MPs release and thrombosis. During SARS-CoV-2 infection, we hypothesised that various factors including inflammatory burden, Ang II, altered shear stress and hypoxic vasoconstriction, could enhance MPs shedding by various cell lineages including the alveolar vascular endothelium and contribute to clot formation.

Procoagulant microparticles are associated with the extent of lung injuries in #COVID19 and pulmonary thrombosishttps://bit.ly/3eX2LPc