Extracellular Vesicles, Inflammation, and Cardiovascular Disease

Astragaloside IV Attenuates Angiotensin II-Induced Inflammatory Responses in Endothelial Cells: Involvement of Mitochondria

Background

Angiotensin II (Ang II)-triggered endothelial inflammation is a critical mechanism contributing to Ang II-related cardiovascular diseases. The inflammation is highly correlated with mitochondrial function. Although astragaloside IV (AS-IV), a primary bioactive ingredient extracted from the traditional Chinese medicine Astragalus membranaceus Bunge that can effectively treat numerous cardiovascular diseases, posses the actions of antiinflammation and antioxidation in vivo, limited data are made available on the impacts of AS-IV on mitochondrial function in endothelial inflammation triggered by Ang II. This study was performed to evaluate the in vitro actions of AS-IV on Ang II-triggered inflammatory responses in endothelial cells, and to further clarify the potential role of mitochondria in the actions.

Methods

Human umbilical vein endothelial cells (HUVECs) were preincubated with AS-IV and then exposed to Ang II for 12 h.

Results

The exposure of HUVECs to Ang II triggered cytokine and chemokine production, the upregulation of adhesive molecules, monocyte attachment, and nuclear factor-kappa B activation. Additionally, our results showed that the inflammatory responses triggered by Ang II were associated with the impairment of mitochondrial function, as evidenced by the reductions of mitochondrial membrane potential, ATP synthesis, and mitochondrial complexes I and III activities. Moreover, the concentrations of malondialdehyde, cellular reactive oxygen species, and mitochondrial superoxide enhanced after HUVECs challenged with Ang II, which were concurrent with the decreases in total superoxide dismutase (SOD) and its isoenzyme activities such as Mn-SOD. These Ang II-induced alterations were reversed by preincubation with AS-IV.

Conclusion

Our data indicate that AS-IV attenuates Ang II-triggered endothelial inflammation possibly via ameliorating mitochondrial function.

Lipid-lowering and antihypertensive drugs on aortic disease risk: insights from Mendelian randomization analysis and real-world pharmacovigilance data

OBJECTIVE

To assess the impact of lipid-lowering drugs (LLDs) and antihypertensive drugs on the risk of aortic diseases.

METHODS

Mendelian randomization was utilized to analyse data from 500 000 participants in the UK Biobank to evaluate the effects of statins, PCSK9 inhibitors (PCSK9i), β-blockers, and calcium channel blockers on the risks of thoracic aortic aneurysm, abdominal aortic aneurysm, and aortic dissection (AD) using genetic variants as proxies. Real-world pharmacovigilance data from the FAERS (FDA Adverse Event Reporting System) database were used.

RESULTS

PCSK9i and statins significantly reduced the risks of aortic aneurysms and AD, respectively. Furthermore, the two LLDs reduced the risk of aortic diseases through certain metabolites. Meanwhile, real-world pharmacovigilance reports also indicated a low incidence of aortic diseases with PCSK9i and statin treatment.

CONCLUSION

LLDs, particularly statins and PCSK9i, significantly protect against aortic diseases, providing a scientific basis for preventing and treating aortic diseases.

Circulating, Extracellular Vesicle-Associated Tissue Factor in Cancer Patients with and without Venous Thromboembolism

Cancer is characterized by chronic inflammation and hypercoagulability, with an excess of venous thromboembolism (VTE). Tissue factor, the initiator of blood coagulation, circulates associated with extracellular vesicles (EV-TF). Studies investigating EV-TF between cancer-associated and non-cancer-associated VTE are lacking. We therefore compared EV-TF in unprovoked VTE (U-VTE), cancer-associated VTE (C-VTE), and cancer without VTE (C-w/o VTE). We also investigated interleukin-6 (IL-6) levels between the same groups. The final population included 68 patients (U-VTE: n = 15; C-VTE: n = 24; C-w/o VTE: n = 29). All patients with VTE were enrolled within 48 h of diagnosis; non-VTE patients were recruited in the oncologic outpatient services. EV were isolated by differential centrifugation from 4 mL of peripheral blood; the final EV pellet (16,000× g for 45 min) was resuspended in 100 μL saline and tested for TF using a one-step clotting assay. There was a statistically significant difference for higher EV-TF in C-VTE and C-w/o VTE compared to U-VTE (p = 0.024; Kruskal-Wallis test). There was no significant difference between C-VTE and C-w/o VTE. Moreover, we did not find any difference in IL-6 levels. These preliminary data suggest that cancer represents, per se, a strong driver of EV-TF generation.

Assessing platelet-derived extracellular vesicles for potential as therapeutic targets in cardiovascular diseases

INTRODUCTION

Cardiovascular disease (CVD) is the leading cause of death worldwide. Platelet-derived extracellular vesicles (PEV) have attracted extensive attention in cardiovascular disease research in recent years because their cargo is involved in a variety of pathophysiological processes, such as thrombosis, immune response, promotion or inhibition of inflammatory response, promotion of angiogenesis as well as cell proliferation and migration.

AREAS COVERED

This review explores the role of PEV in various cardiovascular diseases (such as atherosclerosis, myocardial infarction, ischemia-reperfusion injury, and heart failure), with relation to its molecular cargo (nucleic acids, bioactive lipids, proteins) and aims to provide new insights in the pathophysiologic role of PEV, and methods for preventing and treating cardiovascular diseases based on PEV.

EXPERT OPINION

Studies have shown that the cargo of PEV may be dysregulated during cardiovascular disease and delivery to tissues can result in detrimental pathophysiologic effects. Counteracting this process might have the potential to inhibit inflammation, promote angiogenesis, and inhibit cardiomyocyte death. In addition, PEV have potential as biocompatible and autologous drug carriers. Therefore, better research on the mechanisms how PEV act during cardiovascular disease and could be implemented as a therapeutic will provide new perspectives for the treatment of cardiovascular disease.

Congenital Zika Syndrome: Insights from Integrated Proteomic and Metabolomic Analysis

Background: In this study, we investigated the role of extracellular vesicles (EVs) in the pathogenesis of Congenital Zika Syndrome (CZS). Previous studies have highlighted the role of EVs in intercellular communication and the modulation of biological processes during viral infections, motivating our in-depth analysis. Our objective was to identify specific molecular signatures in the EVs of patients with CZS, focusing on their potential as biomarkers and on cellular pathways affected by the infection. Methods: We conducted advanced proteomic and metabolomic analyses using mass spectrometry for protein and metabolite identification. EVs were isolated from CZS patient samples and control groups using Izon qEV size-exclusion chromatography columns. Results: The analyzed EVs presented distinct molecular profiles in patients with CZS. Proteomic analysis revealed significant alterations in specific proteins, suggesting involvement in the PI3K-AKT-mTOR pathway, while metabolomics highlighted metabolites related to critical processes in Zika virus pathogenesis. These findings suggest a key role for the PI3K-AKT-mTOR pathway in regulating cellular processes during infection and indicate the involvement of EVs in intercellular communication. Additionally, the results identified potential biomarkers capable of aiding early diagnosis and assessing disease progression. Conclusions: This study demonstrates that EVs play a crucial role in intercellular communication during Zika virus infection. The identification of specific alterations in the PI3K-AKT-mTOR pathway highlights a possible therapeutic target, providing new opportunities for the development of more effective treatment strategies for CZS. Our findings significantly advance the understanding of CZS and underscore the need for further investigations using advanced techniques to validate and explore these potential molecular targets.

Extracellular Vesicles: Advanced Tools for Disease Diagnosis, Monitoring, and Therapies

Extracellular vesicles (EVs) are a heterogeneous group of membrane-encapsulated vesicles released by cells into the extracellular space. They play a crucial role in intercellular communication by transporting bioactive molecules such as proteins, lipids, and nucleic acids. EVs can be detected in body fluids, including blood plasma, urine, saliva, amniotic fluid, breast milk, and pleural ascites. The complexity and diversity of EVs require a robust and standardized approach. By adhering to standardized protocols and guidelines, researchers can ensure the consistency, purity, and reproducibility of isolated EVs, facilitating their use in diagnostics, therapies, and research. Exosomes and microvesicles represent an exciting frontier in modern medicine, with significant potential to transform the diagnosis and treatment of various diseases with an important role in personalized medicine and precision therapy. The primary objective of this review is to provide an updated analysis of the significance of EVs by highlighting their mechanisms of action and exploring their applications in the diagnosis and treatment of various diseases. Additionally, the review addresses the existing limitations and future potential of EVs, offering practical recommendations to resolve current challenges and enhance their viability for clinical use. This comprehensive approach aims to bridge the gap between EV research and its practical application in healthcare.

Differences in Plasma Extracellular Vesicles of Different Origin in On-Pump Versus Off-Pump Cardiac Surgery

Coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB) causes a systemic inflammatory response that can worsen patient outcomes. Off-pump surgery has been associated with a reduced inflammatory response. The precise mechanisms and the role of extracellular vesicles (EVs) in this context are not fully understood. This study aimed to investigate the early immune response, including main T- and B-lymphocyte subsets, cytokine profiles, and plasma EVs, in patients undergoing off-pump (n = 18) and on-pump (n = 18) CABG. Thirty-six patients undergoing isolated CABG were enrolled in this randomized control study. Pre- and 24 h postoperative blood samples were analyzed for immune cell populations, cytokine levels, and plasma EV phenotyping. Off-pump CABG triggered a milder immune response than on-pump surgery. On-pump surgery led to greater changes in circulating EVs, particularly platelet- (CD62P+), endothelial- (CD31+), and B-cell-derived (CD19+), as well as platelet- and erythrocyte-derived aggregates (CD41+CD235a+). Levels of platelet-derived EVs, expressing both constitutional and activation markers (CD41+CD62P+) decreased in both groups of patients 24 h after surgery. On-pump cardiac procedures led to an increase in T-regulatory cell-derived EVs (CD73+CD39+), suggesting a potential mechanism for immune suppression compared to off-pump surgery. There were numerous correlations between EV levels and cytokine profiles following on-pump surgery, hinting at a close relationship. Leucocyte-derived EVs exhibited positive correlations with each other and with GRO but showed negative correlations with endothelial-derived EVs (CD90+ and CD31+). Additionally, CD73+ EVs demonstrated positive correlations with platelet counts and with erythrocyte-derived CD235a+ EVs. EV changes were significantly greater after on-pump surgery, highlighting a more pronounced response to this type of surgery and emphasizing the role of EVs as regulators of post-surgical inflammation.

The Role of Ca2+/PI3K/Akt/eNOS/NO Pathway in Astragaloside IV-Induced Inhibition of Endothelial Inflammation Triggered by Angiotensin II

Inflammation induced by angiotensin II (Ang II) is a key event in the progression of numerous cardiovascular diseases. Astragaloside IV (AS-IV), a glycoside extracted from Astragalus membranaceus Bunge, has been shown to inhibit Ang II-induced inflammatory responses in vivo. However, the mechanisms underlying the beneficial effects are still unclear. This study investigated whether AS-IV attenuates endothelial inflammation induced by Ang II via the activation of endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) pathway. Human umbilical vein endothelial cells (HUVECs) were cultured in the presence of AS-IV with or without the specific inhibitor of NOS or Ca2+- and phosphatidylinositol 3-kinase (PI3K)/Akt-dependent cascade prior to Ang II exposure. Incubation of HUVECs with AS-IV enhanced NO production and eNOSser1177 phosphorylation. These responses were abrogated by the inhibition of NOS or Ca2+- and PI3K/Akt-dependent pathway. In addition, preincubation of HUVECs with AS-IV inhibited Ang II-induced cytokine and chemokine production, adhesion molecule expression, monocyte adhesion, and nuclear factor kappa B (NF-κB) activation as evidenced by the attenuation of inhibitor of kappa B alpha phosphorylation and subsequent NF-κB DNA binding. These effects of AS-IV were abolished by the suppression of NOS or Ca2+- and PI3K/Akt-dependent cascade. Our findings indicate that AS-IV attenuates inflammatory responses triggered by Ang II possibly via the activation of Ca2+/PI3K/Akt/eNOS/NO pathway in endothelial cells.

Circulating Extracellular Vesicles from Heart Failure Patients Inhibit Human Cardiomyocyte Activities

Extracellular vesicles (EVs) have been implicated in cardiac remodeling during heart failure (HF). However, the role of circulating EVs (CEVs) in the process of HF is poorly understood. To elucidate the molecular mechanism associated with CEVs in the context of HF, the proteome of 4D label-free EVs from plasma samples was identified. Among the identified proteins, 6 exhibited upregulation while 9 demonstrated downregulation in CEVs derived from HF patients (HCEVs) compared to healthy controls (NCEVs). Our results showed that up-regulated proteins mainly participate in the primary metabolic, glycerolipid metabolic processes, oxidation-reduction process, and inflammatory amplification. In contrast, the down-regulated proteins influenced cell development, differentiation, and proliferation. Compared to NCEVs, HCEVs significantly induced inflammation and triacylglycerol (TAG) accumulation in human cardiomyocytes (HCMs) in vitro. They also compromised their regenerative capacities, triggered endoplasmic reticulum (ER) stress and increased autophagy in HCMs. Further, HCEVs induced differentiation of human cardiac fibroblasts (HCFs), amplifying pro-inflammatory, and pro-fibrotic factors, and enhancing extracellular matrix deposition. Notably, HCEVs are also associated with an increase in the HF biomarker MMP9 within HCFs and demonstrate a negative correlation with autophagic flux. In conclusion, HCEVs appear pivotal in advancing HF via pathological cardiac remodeling.

Extracellular vesicles

Cells, pathogens, and other systems release extracellular vesicles (EVs). The particles promote intercellular communication and contain proteins, lipids, RNA and DNA. Initially considered to be cellular waste in the twentieth century, EVs were becoming recognized for their function in biological communication and control. EVs are divided into many subtypes: exosomes, microvesicles, and apoptotic bodies. Exosomes form in the late endosome/multivesicular body and are released when the compartments fuse with the plasma membrane. Microvesicles are generated by direct budding of the plasma membrane, whereas apoptotic bodies are formed after cellular apoptosis. The new guideline for EVs that describes alternate nomenclature for EVs. The particles modulate the immune response by affecting both innate and adaptive immunity, and their specific the structure allows them to be used as biomarkers to diagnose a variety of diseases. EVs have a wide range of applications, for example, delivery systems for medications and genetic therapies because of their ability to convey specific cellular material. In anti-tumor therapy, EVs deliver therapeutic chemicals to tumor cells. The EVs promote transplant compatibility and reduce organ rejection. Host-parasite interactions, therapeutic and diagnostic for cancer, cardiovascular disease, cardiac tissue regeneration, and the treatment of neurological diseases such as Alzheimer's and Parkinson's. The study of EVs keeps on expanding, revealing new functions and beneficial options. EVs have the potential to change drug delivery, diagnostics, and specific therapeutics, creating a new frontier in biomedical.

A brief review on recent advances in diagnostic and therapeutic applications of extracellular vesicles in cardiovascular disease

Extracellular vesicles (EVs) are important mediators of intercellular communication within the cardiovascular system, playing essential roles in physiological homeostasis and contributing to the pathogenesis of various cardiovascular diseases (CVDs). However, their potential as diagnostic biomarkers and therapeutic agents in rare cardiovascular diseases, such as valvular heart disease (VHD) and cardiomyopathies, remains largely unexplored. This review comprehensively emphasizes recent advancements in extracellular vesicle research, explicitly highlighting their growing significance in diagnosing and potentially treating rare cardiovascular diseases, with a particular focus on valvular heart disease and cardiomyopathies. We highlight the potential of extracellular vesicle-based liquid biopsies as non-invasive tools for early disease detection and risk stratification, showcasing specific extracellular vesicle-associated biomarkers (proteins, microRNAs, lipids) with diagnostic and prognostic value. Furthermore, we discussed the therapeutic promise of extracellular vesicles derived from various sources, including stem cells and engineered extracellular vesicles, for cardiac repair and regeneration through their ability to modulate inflammation, promote angiogenesis, and reduce fibrosis. By integrating the findings and addressing critical knowledge gaps, this review aims to stimulate further research and innovation in extracellular vesicle-based diagnostics and therapeutics of cardiovascular disease.

Extracellular vesicles-Potential link between periodontal disease and diabetic complications

It has long been suggested that a bidirectional impact exists between periodontitis and diabetes. Periodontitis may affect diabetes glycemic control, insulin resistance, and diabetic complications. Diabetes can worsen periodontitis by delaying wound healing and increasing the chance of infection. Extracellular vesicles (EVs) are heterogeneous particles of membrane-enclosed spherical structure secreted by eukaryotes and prokaryotes and play a key role in a variety of diseases. This review will introduce the biogenesis, release, and biological function of EVs from a microbial and host cell perspective, discuss the functional properties of EVs in the development of periodontitis and diabetes, and explore their role in the pathogenesis and clinical application of these two diseases. Their clinical implication and diagnostic value are also discussed.

Evaluating the effect of green tea intake on cardiovascular diseases: A Mendelian randomization study in European and East Asian populations

Previous research shows that more than 70% of cardiovascular diseases (CVDs) are attributed to modifiable risk factors. Here, we investigated relationship between consumption of green tea in European and East Asian populations and risk of CVDs using Mendelian randomization (MR). Instrumental variables for green tea intake were obtained from genome-wide association studies (GWASs) of 64,949 Europeans and 152,653 East Asians. GWASs for CVDs were derived from UK BioBank and BioBank Japan projects. The main method selected for MR analysis was either the inverse variance weighted (IVW) or Wald ratio, depending on the quantity of single nucleotide polymorphisms. Furthermore, we performed sensitivity analyses to confirm the reliability of the findings. Based on the results of IVW, there is no causal relationship between consumption of green tea and risk of 4 CVDs among Europeans (atrial fibrillation: OR = 1.000, 95% CI: 0.995-1.005, P = .910; heart failure: OR = 1.003, 95% CI: 0.994-1.012, P = .542; ischemic stroke: OR = 1.002, 95% CI: 0.993-1.011, P = .690; coronary artery disease: OR = 1.001, 95% CI: 0.996-1.007, P = .677). Sensitivity analyses and supplementary MR analyses also verify the robustness of the findings. Likewise, there was no correlation between the consumption of green tea and the occurrence of CVDs in East Asians. The consumption of green tea is not associated with a reduced risk of CVDs in populations from Europe and East Asia. This means that those who are trying to reduce their risk of CVDs by drinking more green tea may not benefit from doing so.

Evolving Strategies for Extracellular Vesicles as Future Cardiac Therapeutics: From Macro- to Nano-Applications

Cardiovascular disease represents the foremost cause of mortality and morbidity worldwide, with a steadily increasing incidence due to the growth of the ageing population. Cardiac dysfunction leading to heart failure may arise from acute myocardial infarction (MI) as well as inflammatory- and cancer-related chronic cardiomyopathy. Despite pharmacological progress, effective cardiac repair represents an unmet clinical need, with heart transplantation being the only option for end-stage heart failure. The functional profiling of the biological activity of extracellular vesicles (EVs) has recently attracted increasing interest in the field of translational research for cardiac regenerative medicine. The cardioprotective and cardioactive potential of human progenitor stem/cell-derived EVs has been reported in several preclinical studies, and EVs have been suggested as promising paracrine therapy candidates for future clinical translation. Nevertheless, some compelling aspects must be properly addressed, including optimizing delivery strategies to meet patient needs and enhancing targeting specificity to the cardiac tissue. Therefore, in this review, we will discuss the most relevant aspects of the therapeutic potential of EVs released by human progenitors for cardiovascular disease, with a specific focus on the strategies that have been recently implemented to improve myocardial targeting and administration routes.

Harnessing the potential of mesenchymal stem cells-derived exosomes in degenerative diseases

Mesenchymal stem cells (MSCs) have gained attention as a promising therapeutic approach in both preclinical and clinical osteoarthritis (OA) settings. Various joint cell types, such as chondrocytes, synovial fibroblasts, osteoblasts, and tenocytes, can produce and release extracellular vesicles (EVs), which subsequently influence the biological activities of recipient cells. Recently, extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have shown the potential to modulate various physiological and pathological processes through the modulation of cellular differentiation, immune responses, and tissue repair. This review explores the roles and therapeutic potential of MSC-EVs in OA and rheumatoid arthritis, cardiovascular disease, age-related macular degeneration, Alzheimer's disease, and other degenerative diseases. Notably, we provide a comprehensive summary of exosome biogenesis, microRNA composition, mechanisms of intercellular transfer, and their evolving role in the highlight of exosome-based treatments in both preclinical and clinical avenues.

The effect of macrophages and their exosomes in ischemic heart disease

Ischemic heart disease (IHD) is a leading cause of disability and death worldwide, with immune regulation playing a crucial role in its pathogenesis. Various immune cells are involved, and as one of the key immune cells residing in the heart, macrophages play an indispensable role in the inflammatory and reparative processes during cardiac ischemia. Exosomes, extracellular vesicles containing lipids, nucleic acids, proteins, and other bioactive molecules, have emerged as important mediators in the regulatory functions of macrophages and hold promise as a novel therapeutic target for IHD. This review summarizes the regulatory mechanisms of different subsets of macrophages and their secreted exosomes during cardiac ischemia over the past five years. It also discusses the current status of clinical research utilizing macrophages and their exosomes, as well as strategies to enhance their therapeutic efficacy through biotechnology. The aim is to provide valuable insights for the treatment of IHD.

Association of neutrophil-lymphocyte ratio with all-cause and cardiovascular mortality in US adults with diabetes and prediabetes: a prospective cohort study

BACKGROUND

The neutrophil-lymphocyte ratio (NLR) is a novel hematological parameter to assess systemic inflammation. Prior investigations have indicated that an increased NLR may serve as a potential marker for pathological states such as cancer and atherosclerosis. However, there exists a dearth of research investigating the correlation between NLR levels and mortality in individuals with diabetes and prediabetes. Consequently, this study aims to examine the connection between NLR and all-cause as well as cardiovascular mortality in the population of the United States (US) with hyperglycemia status.

METHODS

Data were collected from a total of 20,270 eligible individuals enrolled for analysis, spanning ten cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. The subjects were categorized into three groups based on tertiles of NLR levels. The association of NLR with both all-cause and cardiovascular mortality was evaluated using Kaplan-Meier curves and Cox proportional hazards regression models. Restricted cubic splines were used to visualize the nonlinear relationship between NLR levels and all-cause and cardiovascular mortality in subjects with diabetes after accounting for all relevant factors.

RESULTS

Over a median follow-up period of 8.6 years, a total of 1909 subjects with diabetes died, with 671 deaths attributed to cardiovascular disease (CVD). And over a period of 8.46 years, 1974 subjects with prediabetes died, with 616 cases due to CVD. The multivariable-adjusted hazard ratios (HRs) comparing high to low tertile of NLR in diabetes subjects were found to be 1.37 (95% CI, 1.19-1.58) for all-cause mortality and 1.63 (95% CI, 1.29-2.05) for CVD mortality. And the correlation between high to low NLR tertile and heightened susceptibility to mortality from any cause (HR, 1.21; 95% CI, 1.03-1.43) and CVD mortality (HR, 1.49; 95% CI, 1.08-2.04) remained statistically significant (both p-values for trend < 0.05) in prediabetes subjects. The 10-year cumulative survival probability was determined to be 70.34%, 84.65% for all-cause events, and 86.21%, 94.54% for cardiovascular events in top NLR tertile of diabetes and prediabetes individuals, respectively. Furthermore, each incremental unit in the absolute value of NLR was associated with a 16%, 12% increase in all-cause mortality and a 25%, 24% increase in cardiovascular mortality among diabetes and prediabetes individuals, respectively.

CONCLUSIONS

The findings of this prospective cohort study conducted in the US indicate a positive association of elevated NLR levels with heightened risks of overall and cardiovascular mortality among adults with diabetes and prediabetes. However, potential confounding factors for NLR and the challenge of monitoring NLR's fluctuations over time should be further focused.

Extracellular Vesicles Isolated from Equine Adipose-Derived Stromal Stem Cells (ASCs) Mitigate Tunicamycin-Induced ER Stress in Equine Corneal Stromal Stem Cells (CSSCs)

Corneal ulcers, characterized by severe inflammation of the cornea, can lead to serious, debilitating complications and may be vision-threatening for horses. In this study, we aimed to investigate the role of endoplasmic reticulum (ER) stress in corneal stem progenitor cell (CSSC) dysfunction and explore the potential of equine adipose-derived stromal stem cell (ASC)-derived extracellular vesicles (EVs) to improve corneal wound healing. We showed that CSSCs expressed high levels of CD44, CD45, and CD90 surface markers, indicating their stemness. Supplementation of the ER-stress-inducer tunicamycin to CSSCs resulted in reduced proliferative and migratory potential, accumulation of endoplasmic reticulum (ER)-stressed cells in the G0/G1 phase of the cell cycle, increased expression of proinflammatory genes, induced oxidative stress and sustained ER stress, and unfolded protein response (UPR). Importantly, treatment with EVs increased the proliferative activity and number of cells in the G2/Mitosis phase, enhanced migratory ability, suppressed the overexpression of proinflammatory cytokines, and upregulated the anti-inflammatory miRNA-146a-5p, compared to control and/or ER-stressed cells. Additionally, EVs lowered the expression of ER-stress master regulators and effectors (PERK, IRE1, ATF6, and XBP1), increased the number of mitochondria, and reduced the expression of Fis-1 and Parkin, thereby promoting metabolic homeostasis and protecting against apoptosis in equine CSSCs. Our findings demonstrate that MSCs-derived EVs represent an innovative and promising therapeutic strategy for the transfer of bioactive mediators which regulate various cellular and molecular signaling pathways.

Cardiac macrophage metabolism in health and disease

Cardiac macrophages are essential mediators of cardiac development, tissue homeostasis, and response to injury. Cell-intrinsic shifts in metabolism and availability of metabolites regulate macrophage function. The human and mouse heart contain a heterogeneous compilation of cardiac macrophages that are derived from at least two distinct lineages. In this review, we detail the unique functional roles and metabolic profiles of tissue-resident and monocyte-derived cardiac macrophages during embryonic development and adult tissue homeostasis and in response to pathologic and physiologic stressors. We discuss the metabolic preferences of each macrophage lineage and how metabolism influences monocyte fate specification. Finally, we highlight the contribution of cardiac macrophages and derived metabolites on cell-cell communication, metabolic health, and disease pathogenesis.

Extracellular vesicles in heart failure

Physiologically, extracellular vesicles (EVs) have been implicated as crucial mediators of immune response, cell homeostasis, angiogenesis, cell differentiation and growth, and tissue repair. In heart failure (HF) they may act as regulators of cardiac remodeling, microvascular inflammation, micro environmental changes, tissue fibrosis, atherosclerosis, neovascularization of plaques, endothelial dysfunction, thrombosis, and reciprocal heart-remote organ interaction. The chapter summaries the nomenclature, isolation, detection of EVs, their biologic role and function physiologically as well as in the pathogenesis of HF. Current challenges to the utilization of EVs as diagnostic and predictive biomarkers in HF are also discussed.

Lipoprotein apheresis affects the concentration of extracellular vesicles in patients with elevated lipoprotein (a)

Lipoprotein apheresis (LA) is a therapeutic option for hyperlipoproteinemia(a) (hyper-Lp(a)) and atherosclerotic cardiovascular disease (ASCVD). LA improves blood rheology, reduces oxidative stress parameters and improves endothelial function. The underlying molecular mechanisms of LA beneficial effects are unknown, but it has been suggested that LA exhibits multiple activities beyond simply removing lipoproteins. We hypothesized that LA removes not only lipoproteins, but also extracellular vesicles (EVs). To test this hypothesis, we performed a prospective study in 22 patients undergoing LA for hyper-Lp(a) and ASCVD. Different EVs subtypes were measured before and directly after LA, and after 7 days. We used calibrated flow cytometry to detect total particle concentration (diameter >  ~ 100 nm), total lipoproteins concentration (diameter > 200 nm, RI > 1.51), total EV concentration (diameter > 200 nm, RI < 1.41), concentrations of EVs derived from erythrocytes (CD235a+; diameter > 200 nm, RI < 1.41), leukocytes (CD45+; diameter > 200 nm, RI < 1.41) and platelets (CD61+, PEVs; diameter > 200 nm, RI < 1.41). LA reduced the concentrations of all investigated EVs subtypes and lipoproteins. Lp(a) concentration was lowered by 64.5% [(58% - 71%); p < 0.001]. Plasma concentrations of EVs > 200 nm in diameter derived from platelets (CD61 +), leukocytes (CD45+) and erythrocytes (CD235a+) decreased after single LA procedure by 42.7% [(12.8-54.7); p = 0.005], 42.6% [(29.7-54.1); p = 0.030] and 26.7% [(1.0-62.7); p = 0.018], respectively, compared to baseline. All EV subtypes returned to the baseline concentrations in blood plasma after 7 days. To conclude, LA removes not only Lp(a), but also cell-derived EVs, which may contribute to LA beneficial effects.

Closer to The Heart: Harnessing the Power of Targeted Extracellular Vesicle Therapies

Extracellular vesicles (EVs) have emerged as novel diagnostic and therapeutic approaches for cardiovascular diseases. EVs derived from various origins exhibit distinct effects on the cardiovascular system. However, the application of native EVs is constrained due to their poor stabilities and limited targeting capabilities. Currently, targeted modification of EVs primarily involves genetic engineering, chemical modification (covalent, non-covalent), cell membrane modification, and biomaterial encapsulation. These techniques enhance the stability, biological activity, target-binding capacity, and controlled release of EVs at specific cells and tissues. The diverse origins of cardioprotective EVs are covered, and the applications of cardiac-targeting EV delivery systems in protecting against cardiovascular diseases are discussed. This review summarizes the current stage of research on the potential of EV-based targeted therapies for addressing cardiovascular disorders.

Vitamin D levels and five cardiovascular diseases: A Mendelian randomization study

Cardiovascular disease is the leading cause of death worldwide, whilst vitamin D levels have been found to be associated with cardiovascular disease. To investigate the causal relationship between vitamin D levels and five cardiovascular diseases, a genome-wide association study (GWAS) was carried out using data on vitamin D levels (sample size = 79366), angina pectoris (18168 cases and 187840 controls), coronary heart disease (21012 cases and 197780 controls), lacunar stroke (6030 cases and 248929 controls), heart attack (10693 cases and 451187 controls), and hypertension (55917 cases and 162837 controls), with a Mendelian randomization (MR) analysis being subsequently performed. Six single nucleotide polymorphisms were used as instrumental variables (IVs). In addition, sensitivity analysis was performed to verify the reliability of the MR results here. The results showed a causal relationship between vitamin D levels and angina pectoris (OR = 0.51, 95 % CI: 0.28-0.93, P = 0.03), coronary heart disease (OR = 0.53, 95 % CI: 0.34-0.81, P = 0.004), and lacunar stroke (OR = 0.41, 95 % CI: 0.20-0.86, P = 0.02), but no causal relationship with heart attacks (OR = 1.00, 95 % CI: 0.99-1.01, P = 0.76) or hypertension (OR = 0.99, 95 % CI: 0.73-1.34, P = 0.94). Additionally, our IVs data showed no heterogeneity or pleiotropy, whilst the results of the MR analysis were reliable. This study contributes to the prevention and treatment of these five cardiovascular diseases.

Extracellular Vesicles in Atherosclerosis: State of the Art

Atherosclerosis is a chronic inflammatory disease driven by lipid accumulation in the arteries, leading to narrowing and thrombosis that causes mortality. Emerging evidence has confirmed that atherosclerosis affects younger people and is involved in the majority of deaths worldwide. EVs are associated with critical steps in atherosclerosis, cholesterol metabolism, immune response, endothelial dysfunction, vascular inflammation, and remodeling. Endothelial cell-derived EVs can interact with platelets and monocytes, thereby influencing endothelial dysfunction, atherosclerotic plaque destabilization, and the formation of thrombus. EVs are potential diagnostic and prognostic biomarkers in atherosclerosis (AS) and cardiovascular disease (CVD). Importantly, EVs derived from stem/progenitor cells are essential mediators of cardiogenesis and cardioprotection and may be used in regenerative medicine and tissue engineering.

Cerebral uptake of microvesicles occurs in normocapnic but not hypocapnic passive hyperthermia in young healthy male adults

Passive hyperthermia causes cerebral hypoperfusion primarily from heat-induced respiratory alkalosis. However, despite the cerebral hypoperfusion, it is possible that the mild alkalosis might help to attenuate cerebral inflammation. In this study, the cerebral exchange of extracellular vesicles (microvesicles), which are known to elicit pro-inflammatory responses when released in conditions of stress, were examined in hyperthermia with and without respiratory alkalosis. Ten healthy male adults were heated passively, using a warm water-perfused suit, up to core temperature + 2°C. Blood samples were taken from the radial artery and internal jugular bulb. Microvesicle concentrations were determined in platelet-poor plasma via cells expressing CD62E (activated endothelial cells), CD31+ /CD42b- (apoptotic endothelial cells), CD14 (monocytes) and CD45 (pan-leucocytes). Cerebral blood flow was measured via duplex ultrasound of the internal carotid and vertebral arteries to determine cerebral exchange kinetics. From baseline to poikilocapnic (alkalotic) hyperthermia, there was no change in microvesicle concentration from any cell origin measured (P-values all >0.05). However, when blood CO2 tension was normalized to baseline levels in hyperthermia, there was a marked increase in cerebral uptake of microvesicles expressing CD62E (P = 0.028), CD31+ /CD42b- (P = 0.003) and CD14 (P = 0.031) compared with baseline, corresponding to large increases in arterial but not jugular venous concentrations. In a subset of seven participants who underwent hypercapnia and hypocapnia in the absence of heating, there was no change in microvesicle concentrations or cerebral exchange, suggesting that hyperthermia potentiated the CO2 /pH-mediated cerebral uptake of microvesicles. These data provide insight into a potential beneficial role of respiratory alkalosis in heat stress. KEY POINTS: The hyperthermia-induced hyperventilatory response is observed in most humans, despite causing potentially harmful reductions in cerebral blood flow. We tested the hypothesis that the respiratory-induced alkalosis is associated with lower circulating microvesicle concentrations, specifically in the brain, despite the reductions in blood flow. At core temperature + 2°C with respiratory alkalosis, microvesicles derived from endothelial cells, monocytes and leucocytes were at concentrations similar to baseline in the arterial and cerebral venous circulation, with no changes in cross-brain microvesicle kinetics. However, when core temperature was increased by 2°C with CO2 /pH normalized to resting levels, there was a marked cerebral uptake of microvesicles derived from endothelial cells and monocytes. The CO2 /pH-mediated alteration in cerebral microvesicle uptake occurred only in hyperthermia. These new findings suggest that the heat-induced hyperventilatory response might serve a beneficial role by preventing potentially inflammatory microvesicle uptake in the brain.

Automated atrial fibrillation and ventricular fibrillation recognition using a multi-angle dual-channel fusion network

Atrial fibrillation (AFIB) and ventricular fibrillation (VFIB) are two common cardiovascular diseases that cause numerous deaths worldwide. Medical staff usually adopt long-term ECGs as a tool to diagnose AFIB and VFIB. However, since ECG changes are occasionally subtle and similar, visual observation of ECG changes is challenging. To address this issue, we proposed a multi-angle dual-channel fusion network (MDF-Net) to automatically recognize AFIB and VFIB heartbeats in this work. MDF-Net can be seen as the fusion of a task-related component analysis (TRCA)-principal component analysis (PCA) network (TRPC-Net), a canonical correlation analysis (CCA)-PCA network (CPC-Net), and the linear support vector machine-weighted softmax with average (LS-WSA) method. TRPC-Net and CPC-Net are employed to extract deep task-related and correlation features, respectively, from two-lead ECGs, by which multi-angle feature-level information fusion is realized. Since the convolution kernels of the above methods can be directly extracted through TRCA, CCA and PCA technologies, their training time is faster than that of convolutional neural networks. Finally, LS-WSA is employed to fuse the above features at the decision level, by which the classification results are obtained. In distinguishing AFIB and VFIB heartbeats, the proposed method achieved accuracies of 99.39 % and 97.17 % in intra- and inter-patient experiments, respectively. In addition, this method performed well on noisy data and extremely imbalanced data, in which abnormal heatbeats are much less than normal heartbeats. Our proposed method has the potential to be used as a diagnostic tool in the clinic.

Extracellular vesicles as markers and mediators of pregnancy complications: gestational diabetes, pre-eclampsia, preterm birth and fetal growth restriction

In high income countries, approximately 10% of pregnancies are complicated by pre-eclampsia (PE), preterm birth (PTB), fetal growth restriction (FGR) and/or macrosomia resulting from gestational diabetes (GDM). Despite the burden of disease this places on pregnant people and their newborns, there are still few, if any, effective ways of preventing or treating these conditions. There are also gaps in our understanding of the underlying pathophysiologies and our ability to predict which mothers will be affected. The placenta plays a crucial role in pregnancy, and alterations in placental structure and function have been implicated in all of these conditions. As extracellular vesicles (EVs) have emerged as important molecules in cell-to-cell communication in health and disease, recent research involving maternal- and placental-derived EV has demonstrated their potential as predictive and diagnostic biomarkers of obstetric disorders.  This review will consider how placental and maternal EVs have been investigated in pregnancies complicated by PE, PTB, FGR and GDM and aims to highlight areas where further research is required to enhance the management and eventual treatment of these pathologies.

MicroRNA-22-3p alleviates atherosclerosis by mediating macrophage M2 polarization as well as inhibiting NLRP3 activation

OBJECTIVE

MicroRNA (miR)-22-3p is expressed in atherosclerosis (AS), but its function and regulatory mechanisms remain unclear. Therefore, the effects of miR-22-3p in AS were assessed in this study.

METHODS

MiR-22-3p expression was assessed in AS, and miR-22-3p target genes were predicted using sequencing transcriptomics. The effect of miR-22-3p agomir on atherosclerotic lesions in an AS mouse model were determined by Oil red O, Masson's, and sirius red staining, and by anti-smooth muscle actin and macrophage antigen-3 immunostaining. Gene expression in AS was evaluated by western blot and immunofluorescence.

RESULTS

MiR-22-3p was expressed in AS and control samples (32.5% and 33.9% levels, respectively, relative to total miRNA among six highly expressed miRNAs). In the mouse model of AS, miR-22-3p agomir significantly reduced lipid deposition, proliferation of aortic collagen fibres, and macrophage content. Additionally, inducible nitric oxide synthase, interleukin-6, and tumour necrosis factor-α levels were significantly reduced, and levels of arginase 1 and CD206 were significantly enhanced. MiR-22-3p was found to target janus kinase 1(JAK1), and significantly inhibited the activation of NLR family pyrin domain containing 3 (NLRP3) and JAK1 in mice.

CONCLUSIONS

MiR-22-3p appears to reduce the inflammatory response in AS, which might be achieved by inducing the M2 macrophage phenotype and suppressing NLRP3 activation via JAK1.

Exosomes as a delivery tool of exercise-induced beneficial factors for the prevention and treatment of cardiovascular disease: a systematic review and meta-analysis

Exercise-derived exosomes have been identified as novel players in mediating cell-to-cell communication in the beneficial effects of improving cardiovascular disease (CVD). This review aimed to systematically investigate exosomes as delivery tools for the benefits of exercise in the prevention and treatment of CVD and summarize these outcomes with an overview of their therapeutic implications. Among the 1417 articles obtained in nine database searches (PubMed, EBSCO, Embase, Web of Science, CENTRAL, Ovid, Science Direct, Scopus, and Wiley), 12 articles were included based on eligibility criteria. The results indicate that exercise increases the release of exosomes, increasing exosomal markers (TSG101, CD63, and CD81) and exosome-carried miRNAs (miR-125b-5p, miR-122-5p, miR-342-5p, miR-126, miR-130a, miR-138-5p, and miR-455). These miRNAs mainly regulate the expression of MAPK, NF-kB, VEGF, and Caspase to protect the cardiovascular system. Moreover, the outcome indicators of myocardial apoptosis and myocardial infarction volume are significantly reduced following exercise-induced exosome release, and angiogenesis, microvessel density and left ventricular ejection fraction are significantly increased, as well as alleviating myocardial fibrosis following exercise-induced exosome release. Collectively, these results further confirm that exercise-derived exosomes have a beneficial role in potentially preventing and treating CVD and support the use of exercise-derived exosomes in clinical settings.

Plant-derived nanovesicles: Further exploration of biomedical function and application potential

Extracellular vesicles (EVs) are phospholipid bilayer vesicles actively secreted by cells, that contain a variety of functional nucleic acids, proteins, and lipids, and are important mediums of intercellular communication. Based on their natural properties, EVs can not only retain the pharmacological effects of their source cells but also serve as natural delivery carriers. Among them, plant-derived nanovesicles (PNVs) are characterized as natural disease therapeutics with many advantages such as simplicity, safety, eco-friendliness, low cost, and low toxicity due to their abundant resources, large yield, and low risk of immunogenicity in vivo. This review systematically introduces the biogenesis, isolation methods, physical characterization, and components of PNVs, and describes their administration and cellular uptake as therapeutic agents. We highlight the therapeutic potential of PNVs as therapeutic agents and drug delivery carriers, including anti-inflammatory, anticancer, wound healing, regeneration, and antiaging properties as well as their potential use in the treatment of liver disease and COVID-19. Finally, the toxicity and immunogenicity, the current clinical application, and the possible challenges in the future development of PNVs were analyzed. We expect the functions of PNVs to be further explored to promote clinical translation, thereby facilitating the development of a new framework for the treatment of human diseases.

Proteomic Profiling of Extracellular Vesicles Isolated from Plasma and Peritoneal Exudate in Mice Induced by Crotalus scutulatus scutulatus Crude Venom and Its Purified Cysteine-Rich Secretory Protein (Css-CRiSP)

Increased vascular permeability is a frequent outcome of viperid snakebite envenomation, leading to local and systemic complications. We reported that snake venom cysteine-rich secretory proteins (svCRiSPs) from North American pit vipers increase vascular permeability both in vitro and in vivo. They also induce acute activation of several adhesion and signaling molecules that may play a critical role in the pathophysiology of snakebites. Extracellular vesicles (EVs) have gained interest for their diverse functions in intercellular communication, regulating cellular processes, blood-endothelium interactions, vascular permeability, and immune modulation. They also hold potential as valuable biomarkers for diagnosing, predicting, and monitoring therapeutic responses in different diseases. This study aimed to identify proteins in peritoneal exudate and plasma EVs isolated from BALB/c mice following a 30 min post-injection of Crotalus scutulatus scutulatus venom and its purified CRiSP (Css-CRiSP). EVs were isolated from these biofluids using the EVtrap method. Proteomic analysis of exudate- and plasma-derived EVs was performed using LC-MS/MS. We observed significant upregulation or downregulation of proteins involved in cell adhesion, cytoskeleton rearrangement, signal transduction, immune responses, and vesicle-mediated transports. These findings suggest that svCRiSPs play a crucial role in the acute effects of venom and contribute to the local and systemic toxicity of snakebites.

HSP90-Dependent Upregulation of EZH2 Promotes Hypoxia/Reoxygenation-Induced Pyroptosis by Inhibiting miR-22 in Endothelial Cells

Objective

Endothelial cell pyroptosis induced by hypoxia/reoxygenation (H/R) plays a key role in the pathogenesis of myocardial infarction (MI). However, the underlying mechanism is not clearly elucidated.

Methods

Human umbilical vein endothelial cells (HUVECs) exposed to H/R acted as in vitro model to investigate the mechanism of H/R-induced endothelial cell pyroptosis. CCK-8 assays were performed to investigate the viability of HUVECs. Calcein-AM/PI staining was carried out to quantify the death of HUVECs. The expression level of miR-22 was measured by RT-qPCR. The protein expression levels of zeste 2 polycomb repressive complex 2 subunit (EZH2), NLRP3, cleaved caspase-1 (c-caspase-1), GSDMD-N and heat shock protein 90 (HSP90) were measured by Western blot. Levels of IL-1β and IL-18 in culture medium were detected by ELISA. The intracellular localization of EZH2 was detected by immunofluorescence staining. Chromatin immunoprecipitation (ChIP) assay was used to detect the enrichment of EZH2 and H3K27me3 in the miR-22 promoter region. The binding between miR-22 and NLRP3 in HUVECs was confirmed by the dual luciferase assay. Reciprocal coimmunoprecipitation was conducted to detect the direct interaction between HSP90 and EZH2.

Results

H/R increased EZH2 expression, and the EZH2 siRNA could inhibit H/R-induced pyroptosis in HUVECs. H/R reduced miR-22 expression, which was reversed by EZH2 siRNA. Silencing of miR-22 by its inhibitor reversed EZH2 siRNA-induced pyroptosis inhibition in H/R-exposed HUVECs. Upregulation of miR-22 by its mimic suppressed EZH2 overexpression-enhanced pyroptosis in H/R-exposed HUVECs. ChIP assay confirmed that EZH2 bound to the miR-22 promoter region and repressed miR-22 expression through H3K27me3. Furthermore, luciferase reporter assay indicated that NLRP3 was a direct target of miR- 22 in HUVECs. Finally, HSP90 siRNA inhibited H/R-induced EZH2 expression, miR-22 downregulation, and pyroptosis in HUVECs.

Conclusion

H/R induces pyroptosis via the HSP90/EZH2/miR-22/NLRP3 signaling axis in endothelial cells.

Plasma Pattern of Extracellular Vesicles Isolated from Hepatitis C Virus Patients and Their Effects on Human Vascular Endothelial Cells

Hepatitis C virus (HCV) patients are at increased risk of cardiovascular disease (CVD). In this study, we aimed to evaluate the role of extracellular vesicles (EVs) as pathogenic factors for the onset of HCV-related endothelial dysfunction. Sixty-five patients with various stages of HCV-related chronic liver disease were enrolled in this case series. Plasma EVs were characterized and used to stimulate human vascular endothelial cells (HUVEC), which were examined for cell viability, mitochondrial membrane potential, and reactive oxygen species (ROS) release. The results showed that EVs from HCV patients were mainly of endothelial and lymphocyte origin. Moreover, EVs were able to reduce cell viability and mitochondrial membrane potential of HUVEC, while increasing ROS release. Those harmful effects were reduced by the pretreatment of HUVEC with the NLR family pyrin domain containing 3 (NLRP3)/AMP-activated protein kinase and protein kinase B blockers. In conclusion, in HCV patients, we could highlight a circulating pattern of EVs capable of inducing damage to the endothelium. These data represent a novel possible pathogenic mechanism underlying the reported increase of CVD occurrence in HCV infection and could be of clinical relevance also in relation to the widespread use of antiviral drugs.

Extracellular vesicles as biomarkers and modulators of atherosclerosis pathogenesis

Extracellular vesicles (EVs) are small, lipid bilayer-enclosed structures released by various cell types that play a critical role in intercellular communication. In atherosclerosis, EVs have been implicated in multiple pathophysiological processes, including endothelial dysfunction, inflammation, and thrombosis. This review provides an up-to-date overview of our current understanding of the roles of EVs in atherosclerosis, emphasizing their potential as diagnostic biomarkers and their roles in disease pathogenesis. We discuss the different types of EVs involved in atherosclerosis, the diverse cargoes they carry, their mechanisms of action, and the various methods employed for their isolation and analysis. Moreover, we underscore the importance of using relevant animal models and human samples to elucidate the role of EVs in disease pathogenesis. Overall, this review consolidates our current knowledge of EVs in atherosclerosis and highlights their potential as promising targets for disease diagnosis and therapy.

Low extracellular vesicle concentrations predict survival in patients with heart failure

Background

Heart disease is of worldwide importance due to high morbidity and mortality. Extracellular vesicle (EV) concentration and size represent novel diagnostic and prognostic biomarkers, e.g. in patients with liver cancer, but data on their prognostic relevance in heart disease are lacking. Here, we investigated the role of EV concentration, size and zeta potential in patients with heart disease.

Methods

Vesicle size distribution, concentration and zeta potential were measured by nanoparticle tracking analysis (NTA) in 28 intensive care unit (ICU) and 20 standard care (SC) patients and 20 healthy controls.

Results

Patients with any disease had a lower zeta potential compared to the healthy controls. Vesicle size (X50) was significantly higher in ICU patients (245 nm) with heart disease as compared to those patients with heart disease receiving standard care (195 nm), or healthy controls (215 nm) (p = 0.001). Notably, EV concentration was lower in ICU patients with heart disease (4.68 × 10¹⁰ particles/ml) compared to SC patients with heart disease (7,62 × 10¹⁰ particles/ml) and healthy controls (1.50 × 10¹¹ particles/ml) (p = 0.002). Extracellular vesicle concentration is prognostic for overall survival in patients with heart disease. Overall survival is significantly reduced when the vesicle concentration is below 5.55 × 10¹⁰ particles/ml. Median overall survival was only 140 days in patients with vesicle concentrations below 5.55 × 10¹⁰ particles/ml compared to 211 days in patients with vesicle concentrations above 5.55 × 10¹⁰ particles/ml (p = 0.032).

Summary

Concentration of EVs is a novel prognostic marker in ICU and SC patients with heart disease.

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.

Circulating Extracellular Vesicles: Their Role in Patients with Abdominal Aortic Aneurysm (AAA) Undergoing EndoVascular Aortic Repair (EVAR)

Abdominal aortic aneurysm (AAA) is a frequent aortic disease. If the diameter of the aorta is larger than 5 cm, an open surgical repair (OSR) or an endovascular aortic repair (EVAR) are recommended. To prevent possible complications (i.e., endoleaks), EVAR-treated patients need to be monitored for 5 years following the intervention, using computed tomography angiography (CTA). However, this radiological method involves high radiation exposure in terms of CTA/year. In such a context, the study of peripheral-blood-circulating extracellular vesicles (pbcEVs) has great potential to identify biomarkers for EVAR complications. We analyzed several phenotypes of pbcEVs using polychromatic flow cytometry in 22 patients with AAA eligible for EVAR. From each enrolled patient, peripheral blood samples were collected at AAA diagnosis, and after 1, 6, and 12 months following EVAR implantation, i.e. during the diagnostic follow-up protocol. Patients developing an endoleak displayed a significant decrease in activated-platelet-derived EVs between the baseline condition and 6 months after EVAR intervention. Furthermore, we also observed, that 1 month after EVAR implantation, patients developing an endoleak showed higher concentrations of activated-endothelial-derived EVs than patients who did not develop one, suggesting their great potential as a noninvasive and specific biomarker for early identification of EVAR complications.

Selective Loading and Variations in the miRNA Profile of Extracellular Vesicles from Endothelial-like Cells Cultivated under Normoxia and Hypoxia

Endothelial-like cells may be obtained from CD133⁺ mononuclear cells isolated from human umbilical cord blood (hUCB) and expanded using endothelial-inducing medium (E-CD133 cells). Their use in regenerative medicine has been explored by the potential not only to form vessels but also by the secretion of bioactive elements. Extracellular vesicles (EVs) are prominent messengers of this paracrine activity, transporting bioactive molecules that may guide cellular response under different conditions. Using RNA-Seq, we characterized the miRNA content of EVs derived from E-CD133 cells cultivated under normoxia (N-EVs) and hypoxia (H-EVs) and observed that changing the O₂ status led to variations in the selective loading of miRNAs in the EVs. In silico analysis showed that among the targets of differentially loaded miRNAs, there are transcripts involved in pathways related to cell growth and survival, such as FoxO and HIF-1 pathways. The data obtained reinforce the pro-regenerative potential of EVs obtained from E-CD133 cells and shows that fine tuning of their properties may be regulated by culture conditions.