Leukocyte-derived Microparticles Research Articles

Association between endothelial microparticles and objectively measured physical activity in adults with obesity

BackgroundCardiovascular disease (CVD) is a serious global public health concern that often originates from endothelial dysfunction. Microparticles (MPs) can reflect alterations in tissue or cell function phenotype and responsiveness under various physiological and pathological conditions. MPs derived from endothelial cells may serve as potential biomarkers for CVD. We investigated the association between endothelial-derived MPs (EMPs) and objectively measured physical activity (PA) in adults with obesity and their potential correlation with inflammatory and cardiometabolic biomarkers. MethodsThis cross-sectional study included 50 participants, whose daily movement behaviors were evaluated using activPAL™, which measures moderate-to-vigorous intensity PA (MVPA), light PA (LPA), and standing time. The MP sub-populations were separated from platelet-poor plasma, incubated with multiple antibodies, and analyzed using multi-color flow cytometry. Cytokines, interleukin (IL)−1β, IL-8, E-selectin, P-selectin, and intercellular adhesion molecules (ICAMs), were measured using a customized Luminex® assay kit. Pearson’s correlation coefficients were used to examine associations. ResultsMVPA was associated with lower expressions of ICAM and E-selectin in EMPs, whereas standing time was associated with a higher expression of E-selectin. A positive association exists between leukocyte-derived MP percentage and P-selectin levels in EMPs and E-selectin levels in the plasma. In addition, higher plasma P-selectin level was associated with higher P- and E-selectin levels in EMPs, as was higher inflammation (IL-1β and IL-8). ConclusionThe MPs were negatively associated with MVPA and positively associated with standing time in the participants with obesity. These results underscore the importance of promoting PA interventions, especially at moderate-to-vigorous intensities. Further longitudinal and interventional studies are warranted to elucidate the dynamic interplay among PA, MPs, and endothelial function.

Ozonation of Whole Blood Results in an Increased Release of Microparticles from Blood Cells.

Autohemotherapy with ozonated blood is used in the treatment of a broad spectrum of clinical disorders. Ozone demonstrates strong oxidizing properties and causes damage to cell membranes. The impact of whole-blood ozonation on the release of microparticles from blood and endothelial cells and the concentration of selected markers in the hemostatic system (APTT, PT, D-dimer, fibrinogen) were investigated. Venous blood, obtained from 19 healthy men, was split into four equal parts and treated with air, 15 µg/mL ozone, or 30 µg/mL ozone, or left untreated. The number and types of microparticles released were determined using flow cytometry on the basis of surface antigen expression: erythrocyte-derived microparticles (CD235+), platelet-derived microparticles (CD42+), leukocyte-derived microparticles (CD45+), and endothelial-derived microparticles (CD144+). The study is the first to demonstrate that ozone induces a statistically significant increase in the number of microparticles derived from blood and endothelial cells. Although statistically significant, the changes in some coagulation factors were somewhat mild and did not exceed normal values.

Cell-Derived Microparticles in Blood Products from Blood Donors Deficient in Glucose-6-Phosphate Dehydrogenase.

To quantitate the microparticles (MPs) in whole blood and blood products obtained from blood donors who are deficient in glucose-6-phosphate dehydrogenase (G6PD). The current study analyzed whole blood and blood components prepared from 49 blood donors with G6PD deficiencies and 98 with G6PD-normal results. Packed red blood cells (PRBCs), platelet concentrate (PC), and plasma were prepared according to transfusion laboratory procedures. MP concentrations were determined using a flow cytometer. Blood components prepared from donors with G6PD deficiency were characterized by higher red blood cell-derived MP (RMP) concentration in PRBCs (25,526 vs 18,738 particles/µL) but lower concentrations of platelet-derived MPs (PMPs; in whole blood and PC), leukocyte-derived MPs (LMP; in whole blood and plasma) and total MP (in PC), compared with those from donors with G6PD-normal test results. These results suggest that differences in G6PD status may account for variation in RMP levels during processing.

Exercise and Circulating Microparticles in Healthy Subjects.

This study aimed to explore the relationship between exercise and circulating microparticles (CMPs). PubMed, Web of Science, Embase, and the Cochrane Library databases were searched until August 13, 2020, using the terms "exercise" and "cell-derived microparticles." The Cochrane tool of risk of bias and the Methodological Index for Non-Randomized Studies were used to grade the studies. Twenty-six studies that met criteria were included in this review, including one before-after self-control study, 2 cohort studies, 4 randomized control trials, 5 case-control studies, and 14 descriptive studies. The studies were divided into a single bout and long-term exercise. The types of MPs contained endothelium-derived microparticles (EMPs), leukocyte-derived microparticles (LMPs), platelet-derived microparticles (PMPs), and erythrocyte-derived microparticles (ErMPs). This first systematic review found that the levels of CMPs continued to increase after a single bout of exercise in untrained subjects and were lower in trained subjects. PMPs expressed a transient increase after a single bout of exercise, and the proportion and duration of PMPs increment reduced in long-term exercise. Most studies showed a decline in LMPs in trained subjects after a single bout and long-term exercise, and variable changes were found in EMPs and ErMPs after exercise. A single bout of exercise drives the vessels exposed to high shear stress that promotes the formation of CMPs. However, the decline in CMPs in trained subjects may be attributed to the fact that they have a better ability to adapt to changes in hemodynamics and cellular function during exercise.

Synergistic effects of EMPs and PMPs on pulmonary vascular leakage and lung injury after ischemia/reperfusion

BackgroundVascular leakage is an important pathophysiological process of critical conditions such as shock and ischemia–reperfusion (I/R)-induced lung injury. Microparticles (MPs), including endothelial cell-derived microparticles (EMPs), platelet-derived microparticles (PMPs) and leukocyte-derived microparticles (LMPs), have been shown to participate in many diseases. Whether and which of these MPs take part in pulmonary vascular leakage and lung injury after I/R and whether these MPs have synergistic effect and the underlying mechanism are not known.MethodsUsing hemorrhage/transfusion (Hemo/Trans) and aorta abdominalis occlusion-induced I/R rat models, the role of EMPs, PMPs and LMPs and the mechanisms in pulmonary vascular leakage and lung injury were observed.ResultsThe concentrations of EMPs, PMPs and LMPs were significantly increased after I/R. Intravenous administration of EMPs and PMPs but not LMPs induced pulmonary vascular leakage and lung injury. Furthermore, EMPs induced pulmonary sequestration of platelets and promoted more PMPs production, and played a synergistic effect on pulmonary vascular leakage. MiR-1, miR-155 and miR-542 in EMPs, and miR-126 and miR-29 in PMPs, were significantly increased after hypoxia/reoxygenation (H/R). Of which, inhibition of miR-155 in EMPs and miR-126 in PMPs alleviated the detrimental effects of EMPs and PMPs on vascular barrier function and lung injury. Overexpression of miR-155 in EMPs down-regulated the expression of tight junction related proteins such as ZO-1 and claudin-5, while overexpression of miR-126 up-regulated the expression of caveolin-1 (Cav-1), the trans-cellular transportation related protein such as caveolin-1 (Cav-1). Inhibiting EMPs and PMPs production with blebbistatin (BLE) and amitriptyline (AMI) alleviated I/R induced pulmonary vascular leakage and lung injury.ConclusionsEMPs and PMPs contribute to the pulmonary vascular leakage and lung injury after I/R. EMPs mediate pulmonary sequestration of platelets, producing more PMPs to play synergistic effect. Mechanically, EMPs carrying miR-155 that down-regulates ZO-1 and claudin-5 and PMPs carrying miR-126 that up-regulates Cav-1, synergistically mediate pulmonary vascular leakage and lung injury after I/R.Graphic abstract8k8MRpqBub_wL9wmZ4ez89Video

Cell-Derived Microparticles and Acute Coronary Syndromes: Is there a Predictive Role for Microparticles?

Despite the recent advances in the treatment of Acute Coronary Syndromes (ACS), patients with ACS are still exposed to an increased risk for adverse cardiovascular events, while their prognosis is difficult to determine. Experimental and clinical studies have shown that cell-derived Microparticles (MPs) are associated with the underlying pathophysiological processes that are responsible for atherogenesis and may be causally implicated in the induction of atherothrombosis. In the present article, we aimed to review the available evidence regarding the predictive role of MPs in patients with ACS. Evidence suggests that endothelial MPs are associated with future adverse cardiovascular events in patients with ACS. Platelet-derived MPs have been excessively studied, since they have been found to trigger the coagulation cascade; however, their role as predictors of future cardiovascular events remains debatable. The role of red blood cell-derived MPs is more intriguing; they have been proposed as markers of ongoing thrombosis in patients with ACS, while previous studies have shown that they have anti-coagulant properties in healthy individuals. Leukocyte-derived MPs may also have a predictive role, although the studies regarding these are still limited. Last but not least, it was an interesting discovery that circulating MPs can provide information regarding the angiographic lesions in patients with ACS. The concept of MPs as potential circulating biomarkers in patients with ACS holds much promise. However, large-scale clinical studies are required to evaluate whether the measurement of plasma MPs could be of clinical significance and, thus, dictate a more aggressive treatment strategy in patients with high levels of circulating MPs.

Increased microparticle levels in middle-aged and elderly patients with insomnia may be involved in the pathogenesis of arteriosclerosis.

Insomnia may affect vascular factors and promote arteriosclerosis. Microparticles (MPs) are a heterogeneous group of bioactive small vesicles that can be found in blood and body fluids following activation, necrosis or apoptosis of virtually any eukaryotic cells. MPs are believed to participate in the pathogenesis of atherosclerosis. Few studies have been concerned with the microparticle level in patients with sleep disorder. The purpose of the present study is to measure the levels of endothelial microparticles (EMPs), platelet microparticles (PMPs) and leukocyte-derived microparticles (LMPs) in middle-aged and elderly patients with or without insomnia. Patients with insomnia (N.=30) and without insomnia (N.=18) were enrolled. The insomnia group covered patients with chronic insomnia (N.=16) and acute insomnia (N.=14). Levels of EMPs (CD31 +, CD62E +) and PMPs (CD41a +, CD42a +) and granulocyte-derived (CD11a +) MPs were measured. Flow cytometry was performed on the Beckman Coulter analyzer. Reference gate was defined for the level of MPs using 0.22-0.45-0.88μm microspheres, and the size gate for MPs was 0.5-1.0μm. Of all types of MPs detected, the levels of CD31 +MPs, CD62E +MPs and CD11a +MPs were significantly higher in the insomnia group than in the non-insomnia group (P<0.05). Besides, compared with acute insomnia, the levels of CD31 + MPs and CD11a +MPs were significantly higher in chronic insomnia (P<0.001). In insomnia patients, atherosclerosis progression may be increased by the CD31+ EMPs-mediated apoptosis and endothelial injury. The level of CD11a+ LMPs kept increasing as insomnia persisted, which may indicate atherosclerosis progression.

In Vitro Benchmarking Study of Ventricular Assist Devices in Current Clinical Use

Left ventricular assist devices (LVADs) offer live-saving therapy to transplant-ineligible heart failure patients. A major limitation of the technology includes pump thrombosis, bleeding, and recurrent infection that prove difficult to predict from in vivo animal testing. Shear stress introduced by the LVAD affects more than just hemolysis because platelets, leukocytes, and plasma proteins all contribute to the propensity for complications. It is important to assess overall damage by a new device against a baseline as early as possible in the development process so that design iterations can be made if required. Explanted VADs currently in clinical use (HeartMate 2 and HVAD) were carefully cleaned, inspected, and run at 5 L/min and pressure at 100 mmHg in a standard 500 mL mock circulatory loop using bovine blood. The CentriMag was used as a control pump because of its low blood damage profile. Samples were collected at regular intervals and the following were analyzed: complete cell counts, hemolysis, platelet activation, leukocyte-derived microparticles (LMPs), and von Willebrand factor (vWF) degradation. The HeartMate 2 had the highest levels of hemolysis and platelet activation after 6 hours compared with the HVAD and CentriMag. A decreased granulocyte count, high numbers of LMPs and CD11bBrightHLADR- LMPs, and decreased vWF collagen binding activity was most evident in the HVAD. The results indicate that it is possible to observe differences between different pump designs during in vitro testing that might translate to clinical performance. This study demonstrates the importance of developing standard in vitro total blood damage methods against which device developers could use to modify design to reduce complication risk long before implantation.

Characterization of cell-derived microparticles in synovial fluid and plasma of patients with rheumatoid arthritis

Microparticles (MP) are proposed to play a role in the pathogenesis of rheumatoid arthritis (RA). This study aimed to profile cell lineage-specific MP in patients with RA, osteoarthritis (OA), and healthy controls (HC) in synovial fluid and circulation. Patients with RA (n = 40), OA (n = 30) and HC (n = 33) were included. Cell-free synovial fluid (SF) and platelet-poor plasma samples were stained with annexin V APC and antibodies against CD45, CD20, CD14, CD4, CD8, CD66b, and CD61 for multicolor flow cytometry. Mann-Whitney U test/unpaired T test was used to assess intergroup differences among RA and OA SF and clinical, serological phenotypes of RA based on normality distribution; Kruskal-Wallis test with Dunn's multiple comparisons for comparing plasma MPs among RA, OA, and HC. Correlation between MP proportions and disease parameters was assessed by Spearman's correlation. The proportion of annexin V+ MP in SF of patients with RA [5 (6.35)] [median (IQR)] was higher compared to OA [1.8 (1.35), p < 0.001] and plasma of patients with RA [3.45 (5.63)] compared to OA [1.85 (1.4)] and HC [0.9 (1.1), p < 0.001]. Leukocyte-derived [0.85 (1.17)], granulocyte-derived [0.4 (2.05)], monocyte-derived [0.4 (0.4)], and T cell-derived MP [CD4+ -0.1 (0.1); CD8+ -0.1(0.1)] were higher in RA SF (p < 0.001). Platelet-derived MP (PMP) were the major fraction [1.5 (4.23), p < 0.001] in RA plasma. Leukocyte-derived MP were higher in RA plasma [0.1 (0.2); p < 0.001) than OA and HC. Annexin V+ MP and PMP were higher in the SF of RA with extra-articular manifestations (n = 15), as compared to those without (n = 25) (p = 0.02; p < 0.01, respectively). High SF granulocyte-derived MP were observed in patients with established RA (n = 24), ACPA-positive RA (n = 32) compared to their negative counterparts (p = 0.03; p = 0.02, respectively). Our observations of higher proportions of cell-derived MP in the plasma and synovial fluid of DMARD-naïve RA patients, their clinical and serological phenotypes suggest their role in dynamic cross talk between the joint and systemic circulation, disease pathology, and progression.

Lymphocyte‑derived microparticles stimulate osteoclastogenesis by inducing RANKL in fibroblasts of odontogenic keratocysts.

Leukocyte‑derived microparticles (LMPs) include neutrophil‑, lymphocyte‑ and monocyte‑derived MPs. LMPs act as proinflammatory mediators in autoimmune diseases, infectious diseases and vascular diseases. The present study examined the hypothesis that the percentage of LMPs was increased in patients with inflamed odontogenic keratocysts (OKCs), and investigated the biological effects of Jurkat cell‑derived MPs on the fibroblasts of OKCs in vitro. Cyst fluid MPs, obtained by centrifugation of samples from 20 patients with inflamed OKCs, 3 patients with uninflamed OKCs, 15 patients with radicular cysts (RCs) and 12 patients with inflamed dentigerous cysts (DCs), were analyzed by transmission electron microscopy, dynamic light scattering and immunofluorescence staining. The percentages and concentrations of cyst fluid LMPs were further determined by flow cytometry. The cytokine levels of apoptotic Jurkat cell‑derived MPs and Jurkat cell supernatants were compared by cytokine antibody arrays. Fibroblasts were isolated from 3 patients with OKC and co‑cultured with apoptotic Jurkat cell‑derived MPs with or without interleukin (IL)‑15Rα to detect the levels of matrix metallopeptidase 9 (MMP‑9) and receptor activator of nuclear factor‑κB ligand (RANKL) by reverse transcription‑quantitative polymerase chain reaction and enzyme‑linked immunosorbent assay. The supernatant from Jurkat MPs‑treated fibroblasts was collected to make conditioned medium in which the osteoclastogenesis of Raw264.7 cells was determined. Antibodies against human soluble (s)RANKL were added to the conditioned medium to investigate the inhibitory effects. Mean percentages of lymphocyte‑ and neutrophil‑derived MPs were significantly higher in inflamed OKCs than in DCs. Significant elevations in IL‑15 were detected in apoptotic Jurkat cell‑derived MPs compared with that in Jurkat cell supernatant. Furthermore, higher levels of MMP‑9 and RANKL were detected in Jurkat cell MP‑treated OKC fibroblasts, and this was partially blocked by IL‑15Rα. Increased osteoclast‑like cell formation was observed in the Jurkat MPs‑treated fibroblast supernatant and Raw264.7 co‑culture groups. The anti‑human sRANKL antibody in the Jurkat MPs‑treated fibroblast supernatant group decreased the osteoclastogenesis of the Raw264.7 cells. These results indicate that LMPs serve as novel communication tools that contribute toward the bone resorption of inflamed OKCs by inducing RANKL of OKC fibroblasts via IL‑15.

Leukocyte-derived microparticles exaggerate endothelial senescence and vascular dysfunction induced by high glucose

Microparticles (MPs) are plasma membrane vesicles and vascular effectors. High levels of pro-inflammatory cytokines and procoagulant endothelial-derived MPs circulate in diabetic patients. We have shown that (i) leukocyte-derived MPs shed in response to stress are pro-inflammatory, procoagulant and prosenescent endothelial effectors; (ii) high glucose induces premature endothelial senescence. To determine the possibility that leukocyte-derived MPs affect endothelial senescence and vascular function in response to high glucose. Leukocyte MPs were isolated from rat splenocytes with either 5 mg/ml LPS (MPLPS), 25 ng/ml PMA/1 mM A23187 ionophore (MPPMAi), or vehicle (MPCTL). Porcine coronary artery endothelial cells (ECs) at passage 1 were incubated for 48 h with 1–30 nM MPs in high or low glucose concentration (HG 25 mM, NG 5.5 mM). Senescence-associated β-galactosidase (SA-ß-GAL) activity was assessed by C12FDG, protein expression by Western blot analysis. Pig coronary artery rings were pre-incubated with HG or NG for 12 h prior to addition of 1–30 nM MPs for 12 h. Bradykinin (BK)-induced endothelium-dependent relaxations were assessed in organ chambers, and staining of target proteins by confocal microscopy. At 10 nM, MPLPS and MPPMAi enhanced SA-b-GAL activity both by about 2-fold in NG, and respectively 3 and 3.7-fold in HG. The expression of senescence markers p21, p16 doubled and that of eNOS decreased 2-fold. MPPMAi and MPLPS induced a concentration-dependent inhibition of BK-induced relaxation, inhibition by respectively 10 nM and 30 nM,being 65% in NG, amounting to about 85% in HG, whereas 30 nM MPCTL had no effect. MPPMAi and MPLPS reduced eNOS expression by 60% in NG and 80% in HG. Conversely, VCAM-1, COX-2 were up-regulated. Leukocyte-derived MPs enhance HG-induced alteration of the endothelial function by inducing premature senescence and might contribute to vascular dysfunction in diabetes patients.

Marathon running increases circulating endothelial- and thrombocyte-derived microparticles.

Background Acute vascular effects of high intensity physical activity are incompletely characterized. Circulating microparticles are cellular markers for vascular activation and damage. Methods Microparticles were analysed in 99 marathon runners (49 ± 6 years, 22% female) of the prospective Berlin Beat of Running study. Blood samples were taken within three days before, immediately after and within two days after the marathon run. Endothelial-derived microparticles were labelled with CD144, CD31 and CD62E, platelet-derived microparticles with CD62P and CD42b, leukocyte-derived microparticles with CD45 and monocyte-derived microparticles with CD14. Results Marathon running induced leukocytosis (5.9 ± 0.1 to 14.8 ± 0.3 109/l, p < 0.0001) and increased platelet counts (239 ± 4.6 to 281 ± 5.9 109/l, p < 0.0001) immediately after the marathon. Blood monocytes increased and lymphocytes decreased after the run ( p < 0.0001). Endothelial-derived microparticles were acutely increased ( p = 0.008) due to a 23% increase of apoptotic endothelial-derived microparticles ( p = 0.007) and returned to baseline within two days after the marathon. Thrombocyte-derived microparticles acutely increased by 38% accompanied by an increase in activated and apoptotic thrombocyte-derived microparticles ( p ≤ 0.0001) each. Both monocyte- and leukocyte-derived microparticles were decreased immediately after marathon run ( p < 0.0001) and remained below baseline until day 2. Troponin T increased from 12 to 32 ng/l ( p < 0.0001) immediately after the run and returned to baseline after two days. Conclusion Circulating apoptotic endothelial- and thrombocyte-derived microparticles increased after marathon running consistent with an acute pro-thrombotic and pro-inflammatory state. Exercise-induced vascular damage reflected by microparticles could indicate potential mechanisms of post-exertional cardiovascular complications. Further studies are warranted to investigate microparticles as markers to identify individuals prone to such complications.

Increased circulating leukocyte-derived microparticles in ischemic cerebrovascular disease

ObjectivesCirculating leukocyte-derived microparticles act as proinflammatory mediators that reflect vascular inflammation. In this study, we examined the hypothesis that the quantity of leukocyte-derived microparticles is increased in patients with ischemic cerebrovascular diseases, and investigated utility of various phenotypes of leukocyte-derived microparticles as specific biomarkers of vascular inflammation injury. Additionally we focused on identifying leukocyte-derived microparticles that may be correlated with stroke severity in acute ischemic stroke patients. MethodsThe plasma concentration of leukocyte-derived microparticles obtained by a series of centrifugations of 76 consecutive patients with ischemic cerebrovascular diseases and 70 age-, sex-, and race-matched healthy controls were determined by flow cytometry. ResultsSignificantly elevated numbers of leukocyte (CD45+), monocyte (CD14+), lymphocyte (CD4+), granulocyte (CD15+) derived microparticles were found in the plasma samples of patients ischemic cerebrovascular diseases, compared to healthy controls (p<0.05). Furthermore, the plasma levels of CD14+ microparticles were significantly correlated with stroke severity (r=0.355, p=0.019), cerebral vascular stenosis severity (r=0.255, p=0.025) and stroke subtype (r=0.242, p=0.036). No association with stroke was observed for other leukocyte-derived phenotypes. ConclusionsThese results demonstrate that circulating leukocyte-derived microparticles amounts are increased in patients with ischemic cerebrovascular diseases, compared with healthy controls. As proinflammatory mediators, leukocyte-derived microparticles may contribute to vascular inflammatory and the inflammatory process in acute ischemic stroke. Levels of CD14+ microparticles may be a promising biomarker of ischemic severity and outcome of stroke in the clinic.

Endothelial Cell-Derived Microparticles from Patients with Obstructive Sleep Apnea Hypoxia Syndrome and Coronary Artery Disease Increase Aortic Endothelial Cell Dysfunction

Background/Aims: Obstructive sleep apnea hypoxia syndrome (OSAHS) is an independent risk factor for coronary artery disease (CAD). Treatment of OSAHS improves clinical outcome in some CAD patients, but the relationship between OSAHS and CAD is complex. Microparticles (MPs) are shed by the plasma membrane by either physiologic or pathologic stimulation. In the current study, we investigated the role of MPs in the context of OSAHS. Methods and Results: 54 patients with both suspected coronary artery stenosis and OSAHS were recruited and underwent both coronary arteriography and polysomnography. Circulating MPs were isolated and analyzed by flow cytometry. CAD+OSAHS patients exhibited greater levels of total MPs (Annexin V⁺), erythrocyte-derived MPs (CD235⁺ Annexin V⁺), platelet-derived MPs (CD41⁺ Annexin V⁺), and leukocyte-derived MPs (CD45⁺ Annexin V⁺) compared to CAD alone patients or control. CAD+OSAHS patients expressed the greatest level of endothelial-derived MPs of all cellular origin types (CD144⁺ Annexin V ⁺). Treatment of human aortic endothelial cells (HAECs) with MPs isolated from CAD+OSAHS patients markedly increased HAEC permeability (as detected by FITC-dextran), and significantly upregulated mRNA levels of ICAM-1, VCAM-1, and MCP-1. Conclusion: OSAHS+CAD patients harbor increased levels of MPs, particularly the endothelial cell-derived subtype. When administered to HAECs, OSAHS+CAD patients MPs increase endothelial cell permeability and dysfunction.

Red Wine Prevents the Acute Negative Vascular Effects of Smoking

BackgroundModerate consumption of red wine is associated with fewer cardiovascular events. We investigated whether red wine consumption counteracts the adverse vascular effects of cigarette smoking. MethodsParticipants smoked 3 cigarettes alone or after drinking a titrated volume of red wine. Clinical chemistry, blood counts, plasma cytokine enzyme-linked immunosorbent assays, immunomagnetic separation of CD14+ monocytes for gene expression analysis, fluorescence-activated cell sorting for microparticles, and isolation of circulating mononuclear cells to measure telomerase activity were performed, and urine cotinine levels were quantified. ResultsCompared with baseline, leukocytosis (P = .019), neutrophilia (P <.001), lymphopenia (P <.001), and eosinopenia (P = .008) were observed after only smoking. Endothelial and platelet-, monocyte-, and leukocyte-derived microparticles (P <.001 each) were elevated. In monocytes, messenger RNA expression of interleukin (IL)-6 (2.6- ± 0.57-fold), tumor necrosis factor alpha (2.2- ± 0.62-fold), and IL-1b (2.3- ± 0.44-fold) were upregulated, as was IL-6 (1.2 ± 0.12-fold) protein concentration in plasma. Smoking acutely inhibited mononuclear cell telomerase activity. Markers of endothelial damage, inflammation, and cellular aging were completely attenuated by red wine consumption. ConclusionCigarette smoke results in acute endothelial damage, vascular and systemic inflammation, and indicators of the cellular aging processes in otherwise healthy nonsmokers. Pretreatment with red wine was preventive. The findings underscore the magnitude of acute damage exerted by cigarette smoking in “occasional lifestyle smokers” and demonstrate the potential of red wine as a protective strategy to avert markers of vascular injury.

Time course of various cell origin circulating microparticles in ST-segment elevation myocardial infarction patients undergoing percutaneous transluminal coronary intervention.

The present study aimed to investigate the time course of changes in microparticles (MPs) in patients with ST-segment elevation myocardial infarction (STEMI) that underwent percutaneous transluminal coronary intervention (PCI). A total of 24 STEMI patients undergoing primary PCI were enrolled, and circulating MPs were detected immediately prior to and after PCI, and at 4, 24 and 48 h post-PCI. Standard Megamix beads, based measurement protocols, were employed to measure MPs of different cell origin, including endothelial MPs (EMPs), platelet MPs (PMPs) and leukocyte-derived MPs (LMPs), which were identified by CD144, CD41 and CD45, respectively. The results indicated that PMP levels were evidently elevated immediately after PCI, and reached a maximum level at 48 h. In addition, LMP and EMP levels were significantly decreased immediately after the PCI, and then increased gradually with time. The total quantity of the three aforementioned MP types increased gradually at 48 h following PCI. Furthermore, coronary angiographic Gensini scores were significantly positively correlated with the level of PMPs (r2=0.42; P=0.0006). Log-normalized high sensitivity-C-reactive-protein was also significantly correlated with LMPs (r2=0.86; P<0.01). In conclusion, the time course of the changes in circulating MPs of different cell origin, provided information on possible functions of different MPs in STEMI.

Dynamics of circulating microparticles in obesity after weight loss.

A definitive relationship between adiposity and MP production is yet to be demonstrated. The aim of our study was to prospectively evaluate the levels of microparticles (MP) in a group of 20 III degree obese patients before and after weight loss. Plasma levels of annexin V-MP, endothelial-derived MP, platelet-derived MP (CD61+ and P-Selectin+), leukocyte-derived MP, tissue factor-bearing (TF+) and CD36+MP were prospectively measured in 20 patients with III degree obesity (BMI≥40kg/m(2)) before (T0) and 3 (T3) and 12 (T12) months after sleeve gastrectomy (SLG). Obese patients had lost 18% of their body weight at T3 and 41% at T12. We find that considering all MP, except for endothelial-derived MP, which had significantly decreased at T3, all MP subtypes had significantly decreased at T12. At T12, subjects showed a higher median level of all types of MP, except endothelial-derived MP, compared to T3, but without a statistically significant difference. The percentages of reduction of all the MP were significantly correlated with the percentage of reduction of BMI. The reductions of leukocyte-derived, TF+and CD36+MP were significantly correlated with the reduction of leptin. Moreover, the reductions of leukocyte-derived and CD36+MP were significantly correlated with hs-CRP decrease. The decrease of BMI post-SLG in morbid obesity was matched with a decrease of circulating MP of endothelial, platelet, leukocyte origin, TF+and CD36+. A trend of slight increase in all MP subtypes, except endothelial-derived, was detected 12months after gastrectomy, indicating a possible underlying slow low-grade inflammatory/hypercoagulability state from adipose tissue before the potential overt weight gain.

Cell-Derived Microparticles in Patients with Type 2 Diabetes Mellitus: a Systematic Review and Meta-Analysis

Background/Aims: The aim of this study was to assess the association between circulating cell-derived microparticles (MPs) and type 2 diabetes mellitus (T2DM). Methods: A literature search was performed systematically in PubMed and Embase to identify available case-control or cross-sectional studies that compared different types of cell-derived MPs in patients with T2DM and non-diabetic controls. Pooled standardized mean differences (SMDs) of each MP type were pooled using meta-analysis. Results: Forty-eight studies involving 2,460 patients with T2DM and 1,880 non-diabetic controls were included for systematic review and 34 of which were included for quantitative study by meta-analysis. In the overall analysis, the levels of circulating total MPs (TMPs), platelet-derived MPs (PMPs), monocyte-derived MPs (MMPs) and endothelium-derived MPs (EMPs) were significantly higher in T2DM patients than those in controls (TMPs: SMD, 0.64; 95%CI, 0.12∼1.15; P=0.02; PMPs: SMD, 1.19; 95%CI, 0.88∼1.50; P <0.00001; MMPs: SMD, 0.92; 95%CI, 0.66∼1.17; P <0.00001; EMPs: SMD, 0.73; 95%CI, 0.50∼0.96; P <0.00001). Meanwhile, no significant difference was shown in leukocyte-derived MPs (LMPs) level between diabetic and non-diabetic groups (SMD, 0.37; 95%CI, -0.15∼0.89; P=0.17). Conclusions: The counts of TMPs, PMPs, MMPs and EMPs elevated in patients with T2DM. And cell-derived MPs may play a role in the pathogenesis of T2DM.

Endothelial- and Platelet-Derived Microparticles Are Generated During Liver Resection in Humans

ABSTRACTBackground: Cell-derived plasma microparticles (<1.5 μm) originating from various cell types have the potential to regulate thrombogenesis and inflammatory responses. The aim of this study was to test the hypothesis that microparticles generated during hepatic surgery co-regulate postoperative procoagulant and proinflammatory events. Methods: In 30 patients undergoing liver resection, plasma microparticles were isolated, quantitated, and characterized as endothelial (CD31+, CD41−), platelet (CD41+), or leukocyte (CD11b+) origin by flow cytometry and their procoagulant and proinflammatory activity was measured by immunoassays. Results: During liver resection, the total numbers of microparticles increased with significantly more Annexin V-positive, endothelial and platelet-derived microparticles following extended hepatectomy compared to standard and minor liver resections. After liver resection, microparticle tissue factor and procoagulant activity increased along with overall coagulation as assessed by thrombelastography. Levels of leukocyte-derived microparticles specifically increased in patients with systemic inflammation as assessed by C-reactive protein but are independent of the extent of liver resection. Conclusions: Endothelial and platelet-derived microparticles are specifically elevated during liver resection, accompanied by increased procoagulant activity. Leukocyte-derived microparticles are a potential marker for systemic inflammation. Plasma microparticles may represent a specific response to surgical stress and may be an important mediator of postoperative coagulation and inflammation.

Formation of microparticles in the injured brain of patients with severe isolated traumatic brain injury.

The potential pathophysiological role of circulating microparticles (MPs) has been recognized in various conditions, such as cardiovascular and thrombotic diseases. Traumatic brain injury (TBI) has a complex pathophysiology that involves coagulopathy and inflammation. We investigated endothelial-, platelet-, and leukocyte-derived microparticles (EMPs, PMPs, and LMPs, respectively) in 16 patients with severe isolated TBI. Arterial and cerebrovenous samples were taken repeatedly, during 1-72 h after injury. Subpopulations of MPs, exposing tissue factor (TF) and P-selection, were also studied. MP counts in cerebrovenous samples, irrespective of cellular origin, were higher in TBI cases, compared to healthy controls (peak levels of EMPs were approximately 7 times higher, PMPs 1.4 times higher, and LMPs 2 times higher, respectively; p<0.001 for all). MP counts declined sharply from high levels shortly after the trauma toward slightly elevated levels 72 h later. EMPs and PMPs exposing TF, as well as PMPs exposing P-selection, showed a transcranial gradient with higher concentration in cerebrovenous, compared to arterial, samples. In contrast, LMPs exposing TF were higher in arterial samples, suggesting accumulation of LMPs in the brain. We conclude that the pattern of circulating MPs is altered after TBI. PMPs exposing P-selection and EMPs exposing TF seem to be generated in the injured brain, whereas LMPs exposing TF are accumulated. The pathophysiological significance of these changes in MP pattern in TBI should be further investigated. Including MPs exposing brain-specific antigens in the assessment of brain injury would give further information of origin and likely give additional information of the size of the injury, given that the MP phenotypes investigated in the present study are not brain-specific markers.