Micropartículas de pequeño tamaño como indicadores del estado agudo en la insuficiencia cardiaca sistólica

Circulating microvesicles across a population with various degree of cardiovascular burden are associated with systolic blood pressure

Circulating microvesicles (MVs) have been studied in heterogeneous, divergent, and rather small patient populations with cardiovascular risk . Therefore, we measured endothelial (EMVs), platelet (PMVs) and erythrocyte (RMVs) MVs in patients with divergent cardiovascular risk. We then compared them to coronary artery disease (CAD) and healthy subjects and identified independent MVs' predictors. We enrolled consecutive patients from our Cardiology, Hypertension, Diabetic, Rheumatic, and Nephrology Outpatient Units with MVs measurements. Central blood pressure (BP) was measured by either applanation tonometry or Mobil-O-graph device, while MVs by a standardized flow cytometry protocol. We studied 369 participants with increased cardiovascular risk: 63 with high cardiovascular risk (47 diabetes mellitus type II/DM and 16 end-stage renal disease/ESRD), 92 with chronic inflammatory disorders and 73 with untreated essential hypertension/UEH. We further included 53 subjects with CAD and 87 otherwise healthy individuals. All MVs were lower in patients with increased cardiovascular risk compared to CAD, showing predictive value with high sensitivity and specificity. Furthermore, PMVs and EMVs were increased in patients with cardiovascular risk compared to healthy individuals. DM and ESRD patients had increased EMVs versus UEH and chronic inflammatory disorders. In the whole study population, RMVs were associated only with history of essential hypertension. In multivariate analysis, systolic BP predicted PMVs. Aage, systolic BP, and DM predicted EMVs. In a large population of patients with divergent cardiovascular risk, MVs are independently associated with systolic blood pressure.

Endothelial senescence in vascular diseases: current understanding and future opportunities in senotherapeutics

Senescence compromises the essential role that the endothelium plays in maintaining vascular homeostasis, so promoting endothelial dysfunction and the development of age-related vascular diseases. Their biological and clinical significance calls for strategies for identifying and therapeutically targeting senescent endothelial cells. While senescence and endothelial dysfunction have been studied extensively, distinguishing what is distinctly endothelial senescence remains a barrier to overcome for an effective approach to addressing it. Here, we review the mechanisms underlying endothelial senescence and the evidence for its clinical importance. Furthermore, we discuss the current state and the limitations in the approaches for the detection and therapeutic intervention of target cells, suggesting potential directions for future research.

Complement Properdin Regulates the Metabolo-Inflammatory Response to a High Fat Diet

Background and objectives: Overnutrition leads to a metabolic and inflammatory response that includes the activation of Complement. Properdin is the only amplifier of complement activation and increases the provision of complement activation products. Its absence has previously been shown to lead to increased obesity in mice on a high fat diet. The aim of this study was to determine ways in which properdin contributes to a less pronounced obese phenotype. Materials and Methods: Wild type (WT) and properdin deficient mice (KO) were fed a high-fat diet (HFD) for up to 12 weeks. Results: There was a significant increase in liver triglyceride content in the KO HFD group compared to WT on HFD. WT developed steatosis. KO had an additional inflammatory component (steatohepatitis). Analysis of AKT signalling by phosphorylation array supported a decrease in insulin sensitivity which was greater for KO than WT in liver and kidney. There was a significant decrease of C5L2 in the fat membranes of the KO HFD group compared to the WT HFD group. Circulating microparticles in KO HFD group showed lower presence of C5L2. Expression of the fatty acid transporter CD36 in adipose tissue was increased in KO on HFD and was also significantly increased in plasma of KO HFD mice compared to WT on HFD. CD36 was elevated on microparticles from KO on HFD. Ultrastructural changes consistent with obesity-associated glomerulopathy were observed for both HFD fed genotypes, but tubular strain was greater in KO. Conclusion: Our work demonstrates that complement properdin is a dominant factor in limiting the severity of obesity-associated conditions that impact on liver and kidney. The two receptors, C5L2 and CD36, are downstream of the activity exerted by properdin.

Intravascular cells and circulating microparticles induce procoagulant activity via phosphatidylserine exposure in heart failure

Relatively little information is known about the definitive role of phosphatidylserine (PS) in the hypercoagulability of heart failure (HF). Our objectives were to assess the levels of PS exposure on microparticles (MPs) and blood cells (BCs) in each group of HF patients and to evaluate their procoagulant activity (PCA). HF patients in each NYHA functional class II-IV (II n = 30, III n = 30, IV n = 30) and healthy controls (n = 25) were enrolled in the present study. PS exposure on MPs, BCs was analyzed with flow cytometry. MPs were classified based on their cellular origin: platelets (CD41a⁺), neutrophils (CD66b⁺), endothelial cells (CD31⁺CD41a^-), erythrocytes (CD235a⁺), monocytes (CD14⁺), T lymphocytes (CD3⁺), and B lymphocytes (CD19⁺). PCA was evaluated by clotting time, extrinsic/intrinsic FXa and prothrombinase production assays, as well as fibrin formation assays. Inhibition assays of PCA of PS⁺ BCs and MPs were performed by lactadherin. There was no significant difference in MP cellular origin between healthy and HF subjects. However, the total number of PS⁺ MPs was significantly increased in HF patients compared with healthy controls. In addition, circulating PS⁺ BCs cooperated with PS⁺ MPs to markedly shorten coagulation time and dramatically increase FXa/thrombin generation and fibrin formation in each HF group. Moreover, blockade of exposed PS on BCs and MPs with lactadherin inhibited PCA by approximately 80%. Our results lead us to believe that exposing PS on the injured BCs and MPs played a pivotal role in the hypercoagulability state in HF patients.

Microparticles and cardiovascular diseases

Microparticles are a distinctive group of small vesicles, without nucleus, which are involved as significant modulators in several physiological and pathophysiological mechanisms. Plasma microparticles from various cellular lines have been subject of research. Data suggest that they are key players in development and manifestation of cardiovascular diseases and their presence, in high levels, is associated with chronic inflammation, endothelial damage and thrombosis. The strong correlation of microparticle levels with several outcomes in cardiovascular diseases has led to their utilization as biomarkers. Despite the limited clinical application at present, their significance emerges, mainly because their detection and enumeration methods are improving. This review article summarizes the evidence derived from research, related with the genesis and the function of microparticles in the presence of various cardiovascular risk factors and conditions. The current data provide a substrate for several theories of how microparticles influence various cellular mechanisms by transferring biological information.

Circulating cell-derived microparticles as biomarkers in cardiovascular disease

Cardiovascular diseases (CVDs) are a common cause of death, and a search for biomarkers for risk stratification is warranted. Elevated levels of cell-derived microparticles (MPs) are found in patients with CVD and in groups with risk factors for CVD. Subpopulations of MPs are promising biomarkers for improving risk prediction, as well as monitoring treatment. However, the field has been hampered by technical difficulties, and the ongoing development of sensitive standardized techniques is crucial for implementing MP analyses in the clinic. Large prospective studies are required to establish which MPs are of prognostic value in different patient groups. In this review, we discuss methodological challenges and progress in the field, as well as MP populations that are of interest for further clinical evaluation.

Microparticles in patients undergoing transcatheter aortic valve implantation (TAVI)

Degenerative aortic stenosis (AS) is the most frequent form of acquired valvular heart disease. AS is known to entail endothelial dysfunction caused by increased mechanical shear stress leading to elevated circulatory levels of microparticles. Endothelial and platelet microparticles (EMP and PMP) are small vesicles that originate from activated cells and thrombocytes. We sought to evaluate whether transcatheter aortic valve implantation (TAVI) procedure would elicit effects on circulating EMP and PMP. 92 patients undergoing TAVI procedure for severe AS were included in this study. Samples were obtained at each visit before TAVI, 1 week post-procedure and at 1, 3 and after 6 months after TAVI and were evaluated using flow cytometry. A 12 month clinical follow-up was also performed. CD62E+ EMP concentration before TAVI was 21.11 % (±6.6 % SD) and declined to 20.99 % (±6.8 % SD) after 1 week, to 16.63 % (±5.4 % SD, p < 0.0001) after 1 month, to 17.08 % (±4.6 % SD, p < 0.0001) after 3 months and to 15.94 % (±5.4 % SD, p < 0.0001) after 6 months. CD31+/CD42b-, CD31+/Annexin+/- EMP remained unchanged. CD31+/CD41b+ PMP evidenced a slight, but statistically significant increase after TAVI and remained elevated during the entire follow-up. Apart from a procedure-related improvement in echocardiographic parameters, TAVI procedure led also to a decline in CD62E+ EMP. The reduction in pressure gradients with less hemodynamic shear stress seems also to have beneficially affected endothelial homeostasis.

Pattern of endothelial progenitor cells and apoptotic endothelial cell-derived microparticles in chronic heart failure patients with preserved and reduced left ventricular ejection fraction

Background

Chronic heart failure (HF) remains a leading cause of cardiovascular (CV) mortality and morbidity worldwide. The aim of the study was to investigate whether the pattern of angiogenic endothelial progenitor cells (EPCs) and apoptotic endothelial cell-derived microparticles (EMPs) would be able to differentiate HF with reduced (HFrEF) and preserved (HFpEF) ejection fraction.

Methods

One hundred sixty four chronic HF subjects met inclusion criteria. Patients with global left ventricular ejection fraction ≥ 50% were categorized as the HFpEF group (n = 79) and those with ≤ 45% as the HFrEF group (n = 85). Therefore, to compare the circulating levels of biological markers 35 control subjects without HF were included in the study. All control individuals were age- and sex-matched chronic HF patients. The serum level of biomarkers was measured at baseline. The flow cytometric technique was used for predictably distinguishing circulating cell subsets depending on expression of CD45, CD34, CD14, Tie-2, and CD309 antigens and determining endothelial cell-derived microparticles. CD31⁺/annexin V⁺ was defined as apoptotic endothelial cell-derived MPs, MPs labeled for CD105⁺ or CD62E⁺ were determined as MPs produced due to activation of endothelial cells.

Results

In multivariate logistic regression model T2DM (R² = 0.26; P = 0.001), obesity (R² = 0.22; P = 0.001), previous MI (R² = 0.17; P = 0.012), galectin-3 (R² = 0.67; P = 0.012), CD31⁺/annexin V⁺ EMPs (R² = 0.11; P = 0.001), NT-proBNP (R² = 0.11; P = 0.046), CD14⁺ CD309⁺ cells (R² = 0.058; P = 0.001), and CD14⁺ СD309⁺ Tie-2⁺ cells (R² = 0.044; P = 0.028) were found as independent predictors of HFpEF. Using multivariate Cox-regression analysis adjusted etiology (previous myocardial infarction), cardiovascular risk factors (obesity, type 2 diabetes mellitus) we found that NT-proBNP (OR 1.08; 95% CI = 1.03–1.12; P = 0.001) and CD31⁺/annexin V⁺ EMPs to CD14⁺ CD309⁺ cell ratio (OR 1.06; 95% CI = 1.02–1.11; P = 0.02) were independent predictors for HFpEF.

Conclusion

We found that CD31⁺/annexin V⁺ EMPs to CD14⁺ CD309⁺ cell ratio added to NT-proBNP, clinical data, and cardiovascular risk factors has exhibited the best discriminate value and higher reliability to predict HFpEF compared with NT-proBNP and clinical data/cardiovascular risk factors alone.

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Endothelial progenitors and apoptotic endothelial microparticles contribute in regulation of endothelial function

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Heart failure associates with decreased endothelial progenitors and increased apoptotic endothelial microparticles

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Imbalance between endothelial progenitors and apoptotic endothelial microparticles reflects impaired immune phenotype

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Endothelial progenitors to apoptotic endothelial microparticles ratio might be a surrogate predictor of heart failure

We have searched the clinical studies depicted predictive value of progenitor mononuclears and apoptotic endothelial microparticles in heart failure with preserved (HFpEF) and reduced (HFpEF) left ventricular ejection fraction. Our results have shown that simple measurement of circulating pool of endothelial-derived progenitor cells or apoptotic endothelial microparticles were not probably allowed to create novel model for risk stratification of patients with HEpEF. We suggest that CD31⁺/annexin V⁺ EMPs to CD14⁺ CD309⁺ cell ratio might be considered as an essential tool for prediction and individualized medical care of HFpEF patients.