CD142+/CD61+, CD146+ and CD45+ microparticles predict cardiovascular events in high risk patients following a Mediterranean diet supplemented with nuts

Comparison of assays measuring extracellular vesicle tissue factor in plasma samples: communication from the ISTH SSC Subcommittee on Vascular Biology

BACKGROUND

Scientific and clinical interest in extracellular vesicles (EVs) is growing. EVs that expose tissue factor (TF) bind factor VII/VIIa and can trigger coagulation. Highly procoagulant TF-exposing EVs are detectable in the circulation in various diseases, such as sepsis, COVID-19, or cancer. Many in-house and commercially available assays have been developed to measure EV-TF activity and antigen, but only a few studies have compared some of these assays.

OBJECTIVES

The International Society on Thrombosis and Haemostasis Scientific and Standardization Committee Subcommittee on Vascular Biology initiated a multicenter study to compare the sensitivity, specificity, and reproducibility of these assays.

METHODS

Platelet-depleted plasma samples were prepared from blood of healthy donors. The plasma samples were spiked either with EVs from human milk or EVs from TF-positive and TF-negative cell lines. Plasma was also prepared from whole human blood with or without lipopolysaccharide stimulation. Twenty-one laboratories measured EV-TF activity and antigen in the prepared samples using their own assays representing 18 functional and 9 antigenic assays.

RESULTS

There was a large variability in the absolute values for the different EV-TF activity and antigen assays. Activity assays had higher specificity and sensitivity compared with antigen assays. In addition, there was a large intra-assay and interassay variability. Functional assays that used a blocking anti-TF antibody or immunocapture were the most specific and sensitive. Activity assays that used immunocapture had a lower coefficient of variation compared with assays that isolated EVs by high-speed centrifugation.

CONCLUSION

Based on this multicenter study, we recommend measuring EV-TF using a functional assay in the presence of an anti-TF antibody.

Functional Role of Extracellular Vesicles in Skeletal Muscle Physiology and Sarcopenia: The Importance of Physical Exercise and Nutrition

BACKGROUND/OBJECTIVES

Extracellular vesicles (EVs) play a key role in intercellular communication by transferring miRNAs and other macromolecules between cells. Understanding how diet and exercise modulate the release and content of skeletal muscle (SM)-derived EVs could lead to novel therapeutic strategies to prevent age-related muscle decline and other chronic diseases, such as sarcopenia. This review aims to provide an overview of the role of EVs in muscle function and to explore how nutritional and physical interventions can optimise their release and function.

METHODS

A literature review of studies examining the impact of exercise and nutritional interventions on MS-derived EVs was conducted. Major scientific databases, including PubMed, Scopus and Web of Science, were searched using keywords such as 'extracellular vesicles', 'muscle', 'exercise', 'nutrition' and 'sarcopenia'. The selected studies included randomised controlled trials (RCTs), clinical trials and cohort studies. Data from these studies were synthesised to identify key findings related to the release of EVs, their composition and their potential role as therapeutic targets.

RESULTS

Dietary patterns, specific foods and supplements were found to significantly modulate EV release and composition, affecting muscle health and metabolism. Exercise-induced changes in EV content were observed after both acute and chronic interventions, with a marked impact on miRNAs and proteins related to muscle growth and inflammation. Nutritional interventions, such as the Mediterranean diet and omega-3 fatty acids, have also shown the ability to alter EV profiles, suggesting their potential to improve cardiovascular health and reduce inflammation.

CONCLUSIONS

EVs are emerging as critical mediators of the beneficial effects of diet and exercise on muscle health. Both exercise and nutritional interventions can modulate the release and content of MS-derived EVs, offering promising avenues for the development of novel therapeutic strategies targeting sarcopenia and other muscle diseases. Future research should focus on large-scale RCT studies with standardised methodologies to better understand the role of EVs as biomarkers and therapeutic targets.

Microvesicles with mitochondrial content are increased in patients with sepsis and associated with inflammatory responses

BACKGROUND

Endothelial activation plays an important role in sepsis-mediated inflammation, but the triggering factors have not been fully elucidated. Microvesicles carrying mitochondrial content (mitoMVs) have been implicated in several diseases and shown to induce endothelial activation.

AIM

To explore whether mitoMVs constitute a subset of MVs isolated from plasma of patients with sepsis and contribute to endothelial activation.

METHODS

MVs were isolated from human plasma and characterized by confocal microscopy and flow cytometry. Proinflammatory cytokines, including interleukin (IL)-6, IL-8 and tumour necrosis factor (TNF)-α, and soluble vascular cell adhesion molecule (sVCAM)-1 were detected by ELISA. Human umbilical vein endothelial cells (HUVECs) were stimulated with the circulating MVs to evaluate their effect on endothelial activation.

RESULTS

MitoMVs were observed in plasma from patients with sepsis. Compared with those in healthy controls, expression of MVs, mitoMVs, proinflammatory cytokines and sVCAM-1 was increased. The number of mitoMVs was positively associated with TNF-α and sVCAM-1. In vitro, compared with MVs isolated from the plasma of healthy controls, MVs isolated from the plasma of patients with sepsis induced expression of OAS2, RSAD2, and CXCL10 in HUVECs. MitoMVs were taken up by HUVECs, and sonication of MVs significantly reduced the uptake of mitoMVs by HUVECs and expression of the above three type I IFN-dependent genes.

CONCLUSION

MitoMVs are increased in the plasma of patients with sepsis, which induces elevated expression of type I IFN-dependent genes. This suggests that circulating mitoMVs activate the type I IFN signalling pathway in endothelial cells and lead to endothelial activation.

New factors in heart failure pathophysiology: Immunity cells release of extracellular vesicles

Leukocyte-shed extracellular vesicles (EVs) can play effector roles in the pathophysiological mechanisms of different diseases. These EVs released by membrane budding of leukocytes have been found in high amounts locally in inflamed tissues and in the circulation, indicating immunity cell activation. These EVs secreted by immune cell subsets have been minimally explored and deserve further investigation in many areas of disease. In this study we have investigated whether in heart failure there is innate and adaptive immune cell release of EVs. Patients with chronic heart failure (cHF) (n = 119) and in sex- and age-matched controls without this chronic condition (n = 60). Specifically, EVs were quantified and phenotypically characterized by flow cytometry and cell-specific monoclonal antibodies. We observed that even in well medically controlled cHF patients (with guideline-directed medical therapy) there are higher number of blood annexin-V⁺ (phosphatidylserine⁺)-EVs carrying activated immunity cell-epitopes in the circulation than in controls (p < 0.04 for all cell types). Particularly, EVs shed by monocytes and neutrophils (innate immunity) and by T-lymphocytes and natural-killer cells (adaptive immunity) are significantly higher in cHF patients. Additionally, EVs-shed by activated leukocytes/neutrophils (CD11b⁺, p = 0.006; CD29⁺/CD15⁺, p = 0.048), and T-lymphocytes (CD3⁺/CD45⁺, p < 0.02) were positively correlated with cHF disease severity (NYHA classification). Interestingly, cHF patients with ischemic etiology had the highest levels of EVs shed by lymphocytes and neutrophils (p < 0.045, all). In summary, in cHF patients there is a significant immune cell activation shown by high-release of EVs that is accentuated by clinical severity of cHF. These activated innate and adaptive immunity cell messengers may contribute by intercellular communication to the progression of the disease and to the common affectation of distant organs in heart failure (paracrine regulation) that contribute to the clinical deterioration of cHF patients.

CD36+/CD61+ Microparticles Correlate with the Risk of Percutaneous Cardiac Interventions in Coronary Artery Disease Patients and the Effects of Ticagrelor

PURPOSE

The CD36 scavenger receptor is a mediator of both atherogenesis and thrombosis. We aimed to investigate the prognostic value of CD36+ microparticles (MPs) released from platelets for cardiovascular event presentation in coronary artery disease (CAD) patients and the effects of different antiplatelet drugs on MPs.

METHODS

A total of 101 aspirin-treated CAD patients, who were planned to undergo coronary angiography (CAG), were randomized to either a standard clopidogrel regimen or ticagrelor treatment. Total Annexin V-(AV)+ MPs, CD61+/AV+ MPs, and CD36+/CD61+/AV+ MPs were quantified by flow cytometry at baseline, before and immediately after the operation. The ADP-induced platelet inhibition rate was measured by thromboelastogram (TEG) examination 1 h before the operation.

RESULTS

The baseline levels of CD36+/CD61+/AV+ MPs were significantly increased in percutaneous coronary intervention (PCI) patients (n = 52) compared to no-PCI patients (n = 49) (p < 0.05). A ROC-curve clustered model for CD36+/CD61+/AV+ MPs at baseline predicted an increased risk of PCI [p = 0.009, AUC = 0.761 (95%CI: 0.601 to 0.922)]. Moreover, TEG examination showed that the preoperative proportion of CD36+/CD61+/AV+ MPs was significantly negatively correlated with R time and K time (r = - 0.236, p = 00.026; r = - 0.288, p = 0.006), and positively correlated with MA_ADP (r = 0.226, p = 0.045). Subgroup analysis of PCI group showed that the platelet inhibition rate of ticagrelor was significantly higher (66.05% ± 28.76% vs.31.01% ± 27.33%, p < 0.001), and the number of AV+ MPs, CD61+/AV+ MPs, and CD36+/CD61+/AV+ MPs before the operation was significantly lower than clopidogrel (p < 0.05, all).

CONCLUSION

The high levels of CD36+ MPs derived from activated platelets are related to an increased risk of PCI in CAD patients. Ticagrelor significantly reduced the number of CD61+/AV+ MPs and CD36+/CD61+/AV+ MPs. This trial registration number is ChiCTR1800014908 and the date of registration is 2018.05.01.

Diets and Cellular-Derived Microparticles: Weighing a Plausible Link With Cerebral Small Vessel Disease

Cerebral small vessel disease (CSVD) represents a spectrum of pathological processes of various etiologies affecting the brain microcirculation that can trigger neuroinflammation and the subsequent neurodegenerative cascade. Prevalent with aging, CSVD is a recognized risk factor for stroke, vascular dementia, Alzheimer disease, and Parkinson disease. Despite being the most common neurodegenerative condition with cerebrocardiovascular axis, understanding about it remains poor. Interestingly, modifiable risk factors such as unhealthy diet including high intake of processed food, high-fat foods, and animal by-products are known to influence the non-neural peripheral events, such as in the gastrointestinal tract and cardiovascular stress through cellular inflammation and oxidation. One key outcome from such events, among others, includes the cellular activations that lead to elevated levels of endogenous cellular-derived circulating microparticles (MPs). MPs can be produced from various cellular origins including leukocytes, platelets, endothelial cells, microbiota, and microglia. MPs could act as microthrombogenic procoagulant that served as a plausible culprit for the vulnerable end-artery microcirculation in the brain as the end-organ leading to CSVD manifestations. However, little attention has been paid on the potential role of MPs in the onset and progression of CSVD spectrum. Corroboratively, the formation of MPs is known to be influenced by diet-induced cellular stress. Thus, this review aims to appraise the body of evidence on the dietary-related impacts on circulating MPs from non-neural peripheral origins that could serve as a plausible microthrombosis in CSVD manifestation as a precursor of neurodegeneration. Here, we elaborate on the pathomechanical features of MPs in health and disease states; relevance of dietary patterns on MP release; preclinical studies pertaining to diet-based MPs contribution to disease; MP level as putative surrogates for early disease biomarkers; and lastly, the potential of MPs manipulation with diet-based approach as a novel preventive measure for CSVD in an aging society worldwide.

Liquid Biopsies: Microvesicles in Cardiovascular Disease

Significance: Circulating microvesicles (cMV) are small (0.1-1 μm) phospholipid-rich blebs released by almost all cell types, and their release increases with cell activation and injury, thus reflecting the state of the cell from which they are originated. Microvesicles (MV) are found in the bloodstream, and they affect the phenotype of recipient cells, after local or systemic circulation, by intercellular transfer of their molecular content. Recent Advances: Several studies suggest the use of cell-specific MV subpopulations as predictive biomarkers for cardiovascular diseases (CVDs) at different stages and degrees of severity. In this review, we describe the state of the art of cMV as noninvasive surrogate biomarkers of vascular injury and dysfunction correlated with poor clinical outcomes in CVD. Critical Issues: Despite the growing body of evidence supporting the importance of cMV as hallmarks of CVD and their utility as biomarkers of CVD, the specific roles of each phenotype of cMV in CVD burden and prognosis still remain to be elucidated and validated in large cohorts. In addition, the development of standardized and reproducible techniques is required to be used as biomarkers for disease progression in the clinical setting. Future Directions: A multipanel approach with specific cMV phenotypes, added to current biomarkers and scores, will undoubtedly provide unique prognostic information to stratify patients for appropriate therapy on the basis of their risk of atherothrombotic disease and will open a new research area as therapeutic targets for CVD. MV will add to the implementation of precision medicine by helping the cellular and molecular characterization of CVD patients.

Mediterranean Diet and Endothelial Function: A Review of its Effects at Different Vascular Bed Levels

The Mediterranean diet has recently been the focus of considerable attention as a palatable model of a healthy diet. Its influence on many cardiovascular risk factors, combined with its proven effect in reducing the risk of cardiovascular events in primary prevention, has boosted scientific interest in this age-old nutritional model. Many of the underlying mechanisms behind its health-giving effects have been revealed, from the modulation of the microbiota to the function of high-density lipoproteins (HDL), and it seems to deliver its health benefits mainly by regulating several key mechanisms of atherosclerosis. In this review, we will review the evidence for its regulation of endothelial function, a key element in the early and late stages of atherosclerosis. In addition, we will assess studies which evaluate its effects on the functioning of different arterial territory vessels (mainly the microvascular, peripheral and central vascular beds), focusing mainly on the capillary, brachial and carotid arteries. Finally, we will evaluate the molecular mechanisms which may be involved.

The Mediterranean diet decreases prothrombotic microvesicle release in asymptomatic individuals at high cardiovascular risk

BACKGROUND & AIMS

Circulating microvesicles (cMV) are small phospholipid-rich vesicles that contribute to the atherothrombotic process, and are biomarkers of cardiovascular disease (CVD) burden and progression. Diet is a cornerstone for CVD prevention, but dietary effects on cMV shedding are poorly characterized. We aimed at assessing the long term effects of a Mediterranean diet compared to a low-fat diet (LFD) on MV shedding by cells of the blood and vascular compartments in patients at high cardiovascular risk treated as per guidelines.

METHODS

A total of 155 participants from the PREDIMED trial free of cardiovascular events after a mean follow-up of 5 years (n = 53 from the Mediterranean diet supplemented with extra-virgin olive oil -EVOO-; n = 49 from the Mediterranean diet supplemented with mixed nuts -Nuts-; and n = 53 from the LFD) were included in the study. At baseline and after one-year intervention, cMV were quantified and characterized by flow cytometry to identify their activated parental cell origin and prothrombotic potential by Annexin V (AV) binding.

RESULTS

After one year of dietary intervention, platelet-derived PAC-1⁺/AV⁺ and CD62P⁺/AV⁺ cMV concentrations were lower in the Nuts group compared with the LFD and EVOO interventions (P = 0.036 and 0.003, respectively). In addition, prothrombotic cMV carrying tissue factor (CD142⁺/AV⁺) and CD11a⁺/AV⁺ cMV derived from activated cells, were significantly lower in both Mediterranean diet (EVOO and Nuts) interventions compared to one year of LFD (P < 0.0001 and 0.028, respectively). SMAα⁺/AV^- cMV were lower in the LFD compared to the Nuts group after one year of intervention (P = 0.038).

CONCLUSIONS

cMV are markers of cell activation and vascular injury that appear to be sensitive to dietary changes. Following a Mediterranean diet rich in EVOO or nuts is associated with lower cell activation towards a pro-atherothrombotic phenotype, suggesting a delay in the development of CV complications.

The role of microvesicles and its active molecules in regulating cellular biology

Cell‐derived microvesicles are membrane vesicles produced by the outward budding of the plasma membrane and released by almost all types of cells. These have been considered as another mechanism of intercellular communication, because they carry active molecules, such as proteins, lipids and nucleic acids. Furthermore, these are present in circulating fluids, such as blood and urine, and are closely correlated to the progression of pathophysiological conditions in many diseases. Recent studies have revealed that microvesicles have a dual effect of damage and protection of receptor cells. However, the nature of the active molecules involved in this effect remains unclear. The present study mainly emphasized the mechanism of microvesicles and the active molecules mediating the different biological effects of receptor cells by affecting autophagy, apoptosis and inflammation pathways. The effective ways of blocking microvesicles and its active molecules in mediating cell damage when microvesicles exert harmful effects were also discussed.

The association of P2Y12 inhibitors with pro-coagulatory extracellular vesicles and microRNAs in stable coronary artery disease

Extracellular vesicles (EV) act as a cellular communication tool by carrying lipids, proteins and micro RNA (miR) between cells, thereby playing a pivotal role in thromboembolic processes. The effect of P2Y₁₂ inhibitors on pro-coagulatory, phosphatidylserine (PS)-expressing EV has been investigated previously, but only in vitro or during confounding clinical conditions, such as acute coronary syndrome. Hence, we enrolled 62 consecutive patients 12 month after percutaneous coronary intervention and stent implantation and consequent treatment with dual-antiplatelet therapy consisting of low-dose aspirin and P2Y₁₂ inhibitors. Blood for platelet function testing and EV and miR measurements was taken on the last day of P2Y₁₂ inhibitor intake (baseline, on-treatment) and 10, 30 and 180 days thereafter (off-treatment). We did not observe any influence of P2Y₁₂ inhibitors on the levels of PS-EV or EV sub-population from platelets, erythrocytes, monocytes or endothelial cells, respectively. There was no relationship between platelet function and EV levels in plasma. However, the association of miR-21 and miR-150 with platelet EVs was significantly different between on- and off-treatment measurements. Hence, our study suggests no influence of P2Y₁₂ inhibition on the count of EVs in plasma, but on the potential cargo of platelet-derived EV.

Changes of Circulating Extracellular Vesicles from the Liver after Roux-en-Y Bariatric Surgery

Circulating extracellular vesicles are small particles enclosed by a phospholipid bilayer. Vesicles deriving directly from the cellular membrane by an active budding process retain cell origin specific proteins and RNA. These vesicles carry pathophysiological information from their parental cell and hold the potential to allow analysis of organs without the need for a biopsy. We included in our study 27 patients undergoing bariatric surgery. Hepatic extracellular vesicles were determined by flow cytometry. mRNA specific for hepatic cellular origin was determined in the extracellular vesicle fraction using qPCR. Surgery led to a massive reduction of weight and overall hepatic stress as determined by alanine transaminase (ALT), aspartate transaminase (AST) and γ-glutamyltransferase (GGT). Total extracellular vesicle numbers were reduced after bariatric surgery. Liver specific vesicles identified by HepPar1 or asialoglycoprotein receptor (ASGPR) were significantly reduced after bariatric surgery in both AnnexinV⁺ and AnnexinV⁻ subgroups. When analyzing circulating liver-specific mRNAs, we found reduced levels of these mRNAs after surgery even though total circulating RNA remained unchanged. We conclude that circulating hepatic extracellular vesicles are detectable in samples from patients undergoing gastric bypass surgery. These vesicles are reduced after a reduction of hepatic stress also observed with classic liver enzyme measurements. We conclude that ASGPR or HepPar positive vesicles hold the potential to serve as liver specific vesicle markers.

Extracellular Vesicles as Biomarkers in Cardiovascular Disease; Chances and Risks

The field of extracellular vesicles (EV) is rapidly expanding, also within cardiovascular diseases. Besides their exciting roles in cell-to-cell communication, EV have the potential to serve as excellent biomarkers, since their counts, content, and origin might provide useful information about the pathophysiology of cardiovascular disorders. Various studies have already indicated associations of EV counts and content with cardiovascular diseases. However, EV research is complicated by several factors, most notably the small size of EV. In this review, the advantages and drawbacks of EV-related methods and applications as biomarkers are highlighted.

Microvesicles in Atherosclerosis and Angiogenesis: From Bench to Bedside and Reverse

Atherosclerosis (AT) is a progressive chronic disease involving lipid accumulation, fibrosis, and inflammation in medium and large-sized arteries, and it is the main cause of cardiovascular disease (CVD). AT is caused by dyslipidemia and mediated by both innate and adaptive immune responses. Despite lipid-lowering drugs have shown to decrease the risk of cardiovascular events (CVEs), there is a significant burden of AT-related morbidity and mortality. Identification of subjects at increased risk for CVE as well as discovery of novel therapeutic targets for improved treatment strategies are still unmet clinical needs in CVD. Microvesicles (MVs), small extracellular plasma membrane particles shed by activated and apoptotic cells have been widely linked to the development of CVD. MVs from vascular and resident cells by facilitating exchange of biological information between neighboring cells serve as cellular effectors in the bloodstream and play a key role in all stages of disease progression. This article reviews the current knowledge on the role of MVs in AT and CVD. Attention is focused on novel aspects of MV-mediated regulatory mechanisms from endothelial dysfunction, vascular wall inflammation, oxidative stress, and apoptosis to coagulation and thrombosis in the progression and development of atherothrombosis. MV contribution to vascular remodeling is also discussed, with a particular emphasis on the effect of MVs on the crosstalk between endothelial cells and smooth muscle cells, and their role regulating the active process of AT-driven angiogenesis and neovascularization. This review also highlights the latest findings and main challenges on the potential prognostic, diagnostic, and therapeutic value of cell-derived MVs in CVD. In summary, MVs have emerged as new regulators of biological functions in atherothrombosis and might be instrumental in cardiovascular precision medicine; however, significant efforts are still needed to translate into clinics the latest findings on MV regulation and function.

Role of Platelet-Derived Microvesicles As Crosstalk Mediators in Atherothrombosis and Future Pharmacology Targets: A Link between Inflammation, Atherosclerosis, and Thrombosis

Reports in the last decade have suggested that the role of platelets in atherosclerosis and its thrombotic complications may be mediated, in part, by local secretion of platelet-derived microvesicles (pMVs), small cell blebs released during the platelet activation process. MVs are the most abundant cell-derived microvesicle subtype in the circulation. High concentrations of circulating MVs have been reported in patients with atherosclerosis, acute vascular syndromes, and/or diabetes mellitus, suggesting a potential correlation between the quantity of microvesicles and the clinical severity of the atherosclerotic disease. pMVs are considered to be biomarkers of disease but new information indicates that pMVs are also involved in signaling functions. pMVs evoke or promote haemostatic and inflammatory responses, neovascularization, cell survival, and apoptosis, processes involved in the pathophysiology of cardiovascular disease. This review is focused on the complex cross-talk between platelet-derived microvesicles, inflammatory cells and vascular elements and their relevance in the development of the atherosclerotic disease and its clinical outcomes, providing an updated state-of-the art of pMV involvement in atherothrombosis and pMV potential use as therapeutic agent influencing cardiovascular biomedicine in the future.