Impaired immune phenotype of circulating endothelial-derived microparticles in patients with metabolic syndrome and diabetes mellitus

Exploring adipose tissue-derived extracellular vesicles in inter-organ crosstalk: Implications for metabolic regulation and adipose tissue function

Intercellular and inter-organ communication systems are vital for tissue homeostasis and disease development, utilizing soluble bioactive molecules for signaling. The field of extracellular vesicle (EV) biology has rapidly expanded in recent decades, highlighting EVs as effective bioactive nanovectors for cell-to-cell communication in various physiological and pathological contexts. Numerous studies indicate that adipocyte-derived EVs are crucial components of the adipose secretome, playing a key role in autocrine and paracrine interactions within adipose tissue, as well as in endocrine signaling. This review aims to present an updated perspective on EVs as mediators of communication between adipose tissue and other organs, while also examining their therapeutic potential in the light of recent advancements in EV biology research.

A novel rat model of cerebral small vessel disease based on vascular risk factors of hypertension, aging, and cerebral hypoperfusion

Cerebral small vessel disease (CSVD) is a major cause of vascular cognitive impairment and functional loss in elderly patients. Progressive remodeling of cerebral microvessels due to arterial hypertension or other vascular risk factors, such as aging, can cause dementia or stroke. Typical imaging characteristics of CSVD include cerebral microbleeds (CMB), brain atrophy, small subcortical infarctions, white matter hyperintensities (WMH), and enlarged perivascular spaces (EPVS). Nevertheless, no animal models that reflect all the different aspects of CSVD have been identified. Here, we generated a new CSVD animal model using D-galactose (D-gal) combined with cerebral hypoperfusion in spontaneously hypertensive rats (SHR), which showed all the hallmark pathological features of CSVD and was based on vascular risk factors. SHR were hypodermically injected with D-gal (400 mg/kg/d) and underwent modified microcoil bilateral common carotid artery stenosis surgery. Subsequently, neurological assessments and behavioral tests were performed, followed by vascular ultrasonography, electron microscopy, flow cytometry, and histological analyses. Our rat model showed multiple cerebrovascular pathologies, such as CMB, brain atrophy, subcortical small infarction, WMH, and EPVS, as well as the underlying causes of CSVD pathology, including oxidative stress injury, decreased cerebral blood flow, structural and functional damage to endothelial cells, increased blood-brain barrier permeability, and inflammation. The use of this animal model will help identify new therapeutic targets and subsequently aid the development and testing of novel therapeutic interventions. Main process of the study: Firstly, we screened for optimal conditions for mimicking aging by injecting D-gal into rats for 4 and 8 weeks. Subsequently, we performed modified microcoil BCAS intervention for 4 and 8 weeks in rats to screen for optimal hypoperfusion conditions. Finally, based on these results, we combined D-gal for 8 weeks and modified microcoil BCAS for 4 weeks to explore the changes in SHR.

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.

Effects of Bariatric Surgery on Blood and Vascular Large Extracellular Vesicles According to Type 2 Diabetes Status

CONTEXT

Large extracellular vesicles (lEVs) enriched for endothelial and blood cell markers are increased in metabolic conditions such as obesity or type 2 diabetes (T2D), actively contribute to the atherosclerotic process, and have been identified as diagnostic and prognostic biomarkers for cardiovascular disease (CVD). Although bariatric surgery (BS) in individuals with obesity is related to decreased cardiovascular (CV) risk and increased life expectancy, after BS these subjects are still at higher CV risk than the general population.

OBJECTIVE

We aimed to compare the lEV profiles between individuals with obesity, with or without T2D, before and 1 year after BS, and normal-weight controls.

METHODS

Prospective longitudinal study with individuals eligible for BS, with or without T2D (T2D and OB groups, respectively) and healthy controls (HC group) matched by age and sex. The concentration and phenotype of lEVs were assessed by flow cytometry.

RESULTS

The study cohort included 108 individuals (age 48.0 ± 10.5 years; 84.3% females). Before BS, the OB group presented higher concentrations of lEV enriched for endothelial and blood cell biomarkers than the HC group, but lower concentrations than those observed in the T2D group (P < .05). BS resulted in a significant reduction in most of the lEVs enriched for cell-specific markers in both subgroups. lEV differences between OB and T2D groups were no longer observed after BS (P > .05). However, compared with HC group, OB and T2D groups still showed increased concentrations of lEVs enriched for platelet and endothelial cell markers (P < .05).

CONCLUSION

At 1 year after BS, lEV concentrations remain above the physiological range. These abnormalities might contribute to explaining the increased CV risk after BS and underscore the importance of long-term CV risk factor control in post-BS individuals.

Pentraxin 3 in Circulating Microvesicles: a Potential Biomarker for Acute Heart Failure After Cardiac Surgery with Cardiopulmonary Bypass

The aim of this study was to investigate whether pentraxin 3 (PTX3) in microvesicles (MVs) can be a valuable biomarker for the prediction of acute heart failure (AHF) after cardiac surgery with cardiopulmonary bypass (CPB). One hundred and twenty-four patients undergoing cardiac surgery with CPB were included and analyzed (29 with AHF and 95 without AHF). The concentrations of PTX3 in MVs isolated from plasma were measured by ELISA kits before, 12 h, and 3 days after surgery. Patients' demographics, medical history, surgical data, and laboratory results were collected. The levels of PTX3 in MVs were significantly elevated during perioperative surgery, which was increased more in the AHF group. The concentrations of PTX3 in MVs at postoperative 12 h were independent risk factors for AHF with the area under the ROC curve of 0.920. The concentration of PTX3 in MVs may be a novel biomarker for prediction of AHF after cardiac surgery.

Circulating microparticles as indicators of cardiometabolic risk in PCOS

Polycystic ovary syndrome (PCOS), the most prevalent endocrine disturbance of the female reproductive system, is associated with several pathologic conditions, such as metabolic syndrome, obesity, diabetes, dyslipidemia, and insulin resistance, all of which are tightly connected to its progression. These factors are associated with a type of extracellular vesicle, ie, microparticles (MPs), released by shedding due to cell activation and apoptosis. Circulating MPs (cMPs) are secreted by a variety of cells, such as platelets, endothelial, leukocytes, and erythrocytes, and contain cytoplasmic substances derived from parent cells that account for their biologic activity. Current evidence has clearly shown that increased cMPs contribute to endothelial dysfunction, diabetes, hypertriglyceridemia, metabolic syndrome, cardiovascular abnormalities as well as PCOS. It has also been reported that platelet and endothelial MPs are specifically increased in PCOS thus endangering vascular health and subsequent cardiovascular disease. Given the importance of cMPs in the pathophysiology of PCOS, we review the role of cMPs in PCOS with a special focus on cardiometabolic significance.

[Production and internalization of extracellular vesicules in normal and under conditions of hyperglycemia and insulin resistance]

Extracellular vesicles (EVs) are spherical structures of cell membrane origin, ranging in the size from 40 nm to 5000 nm. They are involved in the horizontal transfer of many proteins and microRNAs. The mechanisms EV internalization include clathrin-dependent endocytosis, caveolin-dependent endocytosis, raft-mediated endocytosis, and macropinocytosis. Type 2 diabetes mellitus (T2DM) is a common group of metabolic disorders in adults; the incidence and prevalence increase in parallel with the obesity epidemic. Since adipose tissue plays a crucial role in the development of insulin resistance, EVs secreted by adipose tissue can be a kind of information transmitter in this process. EVs of adipocytic origin are predominantly absorbed by tissue macrophages, adipocytes themselves, hepatocytes, and skeletal muscles. This contributes to the M1 polarization of macrophages, a decrease in glucose uptake by hepatocytes and myocytes due to the transfer of functionally active microRNAs by these EVs, which affect carbohydrate and lipid metabolism. Patients with T2DM and impaired glucose tolerance have significantly higher levels of CD235a-positive (erythrocyte) EVs, as well as a tendency to increase CD68-positive (leukocyte) and CD62p-positive (platelets/endothelial cells) EVs. The levels of CD31+/CD146-positive BB (endothelial cells) were comparable between diabetic and euglycemic patients. EVs from diabetic patients were preferably internalized by monocytes (mainly classical and intermediate monocyte fractions and to a lesser extent by non-classical monocyte fractions) and B cells compared to euglycemic patients. Internalization of EVs from patients with T2DM by monocytes leads to decreased apoptosis, changes in differentiation, and suppression of reactions controlling oxidative stress in monocytes. Thus, insulin resistance increases secretion of EVs, which are preferentially internalized by monocytes and influence their function. EVs are considered as sources of promising clinical markers of insulin resistance, complications of diabetes mellitus (endothelial dysfunction, retinopathy, nephropathy, neuropathy), and markers of EVs can also be used to monitor the effectiveness of therapy for these complications.

Roles of extracellular vesicles in the aging microenvironment and age-related diseases

Cellular senescence is a persistently hypoproliferative state with diverse stressors in a specific aging microenvironment. Senescent cells have a double-edged sword effect: they can be physiologically beneficial for tissue repair, organ growth, and body homeostasis, and they can be pathologically harmful in age-related diseases. Among the hallmarks of senescence, the SASP, especially SASP-related extracellular vesicle (EV) signalling, plays the leading role in aging transmission via paracrine and endocrine mechanisms. EVs are successful in intercellular and interorgan communication in the aging microenvironment and age-related diseases. They have detrimental effects on downstream targets at the levels of immunity, inflammation, gene expression, and metabolism. Furthermore, EVs obtained from different donors are also promising materials and tools for antiaging treatments and are used for regeneration and rejuvenation in cell-free systems. Here, we describe the characteristics of cellular senescence and the aging microenvironment, concentrating on the production and function of EVs in age-related diseases, and provide new ideas for antiaging therapy with EVs.

Effects of modified-Paleo and moderate-carbohydrate diets on body composition, serum levels of hepatokines and adipocytokines, and flow cytometric analysis of endothelial microparticles in adults with metabolic syndrome: a study protocol for a randomized clinical trial

Background

Metabolic syndrome is a combination of metabolic risk factors causing a pathological condition that increases the risk of non-communicable diseases, such as diabetes and cardiovascular diseases. A variety of dietary approaches have been examined to halt this rapid trend; however, the effects of modified-Paleo diet and medium-carbohydrate diet on inflammation, adipokines, hepatokines, and the profile of endothelial microparticles in individuals with metabolic syndrome have not been investigated in detail. The present study is designed to examine the effect of modified-Paleo and moderate-carbohydrate diet with two delivery modes: “fixed diet plan” vs “calorie counting” on weight, body composition, serum levels of some hepatokines and adipocytokines, and flow cytometric analysis of endothelial microparticles in adults with metabolic syndrome.

Methods

Eighty metabolic syndrome patients will be recruited in this study. They will be randomly allocated to one of the following 4 groups: (1) receiving a modified-Paleo diet with calorie counting, (2) receiving a modified-Paleo diet with a fixed diet plan, (3) receiving a medium-carbohydrate diet with calorie counting, and (4) receiving a medium-carbohydrate diet with a fixed diet plan for 10 weeks. Weight, height, waist circumference, and body composition will be assessed at the study baseline and at the end of the trial. Serum insulin, asprosin, chemerin, FGF-21, CTRP-1, PYY, ghrelin, plasma EMPs (CD31+/CD42b− and CD144+/CD42b−), lipid profile, glycemic indices, hs-CRP, leptin, vitamin C, creatinine and satiety, hunger, fullness, and desire to eat (via visual analog scales) will be measured at the study baseline and at the end of the trial. Insulin resistance and insulin sensitivity will be determined using the HOMA-IR and QUICKI equations.

Discussion

To the best of our knowledge, this is the first randomized controlled trial that will determine the effect of modified-Paleo and moderate-carbohydrate diet on weight, body composition, serum levels of some hepatokines and adipocytokines, and the profile of EMPs in adults with metabolic syndrome. Moreover, the effects of different diet delivery modes, including “fixed diet plan” and “calorie counting” will also be analyzed. The results of this trial can provide clinical witnesses on the effectiveness of carbohydrate-restricted diets in ameliorating metabolic status and prevent the development of chronic diseases.

Trial registration

Iranian Registry of Clinical Trials IRCT2016121925267N4. Registered on 26 July 2017

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05612-y.

Interplay between Endoplasmic Reticulum Stress and Large Extracellular Vesicles (Microparticles) in Endothelial Cell Dysfunction

Upon increased demand for protein synthesis, accumulation of misfolded and/or unfolded proteins within the endoplasmic reticulum (ER), a pro-survival response is activated termed unfolded protein response (UPR), aiming at restoring the proper function of the ER. Prolonged activation of the UPR leads, however, to ER stress, a cellular state that contributes to the pathogenesis of various chronic diseases including obesity and diabetes. ER stress response by itself can result in endothelial dysfunction, a hallmark of cardiovascular disease, through various cellular mechanisms including apoptosis, insulin resistance, inflammation and oxidative stress. Extracellular vesicles (EVs), particularly large EVs (lEVs) commonly referred to as microparticles (MPs), are membrane vesicles. They are considered as a fingerprint of their originating cells, carrying a variety of molecular components of their parent cells. lEVs are emerging as major contributors to endothelial cell dysfunction in various metabolic disease conditions. However, the mechanisms underpinning the role of lEVs in endothelial dysfunction are not fully elucidated. Recently, ER stress emerged as a bridging molecular link between lEVs and endothelial cell dysfunction. Therefore, in the current review, we summarized the roles of lEVs and ER stress in endothelial dysfunction and discussed the molecular crosstalk and relationship between ER stress and lEVs in endothelial dysfunction.

Concentration of circulating microparticles: a new biomarker of acute heart failure after cardiac surgery with cardiopulmonary bypass

Acute heart failure (AHF) is a severe complication after cardiac surgery with cardiopulmonary bypass (CPB). Although some AHF biomarkers have been used in clinic, they have limitations when applied in the prediction and diagnosis of AHF after cardiac surgery with CPB, and there are still no effective and specific biomarkers. We and other researchers have shown that circulating microparticles (MPs) increased in a variety of cardiovascular diseases. However, whether the concentration of circulating MPs could be a new biomarker for AHF after cardiac surgery remains unknown. Here, 90 patients undergoing cardiac surgery with CPB and 45 healthy subjects were enrolled. Patients were assigned into AHF (n=14) or non-AHF (n=76) group according to the diagnosis criteria of AHF. The concentrations of circulating MPs were determined before, as well as 12 h and 3 days after operation with nanoparticle tracking analysis technique. MPs concentrations in patients before surgery were significantly higher than those of healthy subjects. Plasma levels of MPs were significantly elevated at 12 h after surgery in patients with AHF, but not in those without AHF, and the circulating MPs concentrations at 12 h after surgery were higher in AHF group compared with non-AHF group. Logistic regression analysis indicated that MPs concentration at postoperative 12 h was an independent risk factor for AHF. The area under receiver operating characteristic curve for MPs concentration at postoperative 12 h was 0.81 and the best cut-off value is 5.20×10⁸ particles mL^-1 with a sensitivity of 93% and a specificity of 10%. These data suggested that the concentration of circulating MPs might be a new biomarker for the occurrence of AHF after cardiac surgery with CPB.

The correlation between CT features and insulin resistance levels in patients with T2DM complicated with primary pulmonary tuberculosis

The aim is to investigate the correlation between computed tomography (CT) features and insulin resistance levels in patients with type 2 diabetes mellitus (T2DM) complicated with primary pulmonary tuberculosis (PTB). Nearly, 268 untreated PTB patients complicated with T2DM were divided into two groups according to the optimal cutoff value of HOMA-IR score for the Chinese population: HOMA-IR ≤ 2.69 (Group I: 74 patients), >2.69 (Group II: 194 patients). The basic characteristics and changes of CT manifestations were analyzed. In the two groups, the detection rate of large segmented leafy shadow was 39.2% and 78.9%; the air bronchogram sign detection rate was 40.5% and 80.9%; the discovery rate of mouth-eaten cavity was 33.8% and 73.7%; the thin-walled cavity detection rate was 2.7% and 16.0%; the rate of multiple cavities was 35.1% and 69.6%; and bronchial tuberculosis was found in 4.1% and 35.6%, respectively. The detection rates of lesions in Group II were significantly higher than in Group I (p < .05). HOMA-IR was found independently associated with large segmented leafy shadow, air bronchial sign, thin-walled cavity, and bronchial tuberculosis. The level of insulin resistance can effectively reflect the severity of PTB patients with T2DM. CT scan can directly provide image information in clinics. These two examinations can guide clinicians to accurately formulate subsequent treatment plans.

Extracellular Endothelial Cell-Derived Vesicles: Emerging Role in Cardiac and Vascular Remodeling in Heart Failure

Extracellular vesicles play a pivotal role in numerous physiological (immune response, cell-to-cell cooperation, angiogenesis) and pathological (reparation, inflammation, thrombosis/coagulation, atherosclerosis, endothelial dysfunction) processes. The development of heart failure is strongly associated with endothelial dysfunction, microvascular inflammation, alteration in tissue repair, and cardiac and vascular remodeling. It has been postulated that activated endothelial cell-derived vesicles are not just transfer forms of several active molecules (such as regulatory peptides, coagulation factors, growth factors, active molecules, hormones that are embedded onto angiogenesis, tissue reparation, proliferation, and even prevention from ischemia/hypoxia), but are instead involved in direct myocardial and vascular damage due to regulation of epigenetic responses of the tissue. These responses are controlled by several factors, such as micro-RNAs, that are transferred inside extracellular vesicles from mother cells to acceptor cells and are transductors of epigenetic signals. Finally, it is not a uniform opinion whether different phenotypes of heart failure are the result of altered cardiac and vascular reparation due to certain epigenetic responses, which are yielded by co-morbidities, such as diabetes mellitus and obesity. The aim of the review is to summarize knowledge regarding the role of various types of extracellular endothelial cell-derived vesicles in the regulation of cardiac and vascular remodeling in heart failure.

Altered signature of apoptotic endothelial cell-derived microvesicles predicts chronic heart failure phenotypes

Aim: to evaluate the associations between signatures of apoptotic endothelial cell-derived microvesicles (MVs) with phenotypes of chronic heart failure (HF). Methods: The study cohort consisted of 388 prospectively involved subjects with HF patients with predominantly reduced left ventricular ejection fraction (HFrEF), HF with preserved ejection fraction (HFpEF) and HF with mid-range ejection fraction (HFmrEF). All biomarkers were measured at baseline. Results: The number of circulating CD31+/annexin V+ MVs in HFrEF and HFmrEF patients was similar. The number of circulating CD144+/annexin V+ MVs in HFrEF patients was significantly higher than HFmrEF and HFpEF. We determined that a combination of number of circulating CD31+/annexin V+ MVs and Gal-3 was the best predictor of HFpEF and that number of circulating CD144+/annexin V+ MVs is able to increase predictive capabilities of soluble ST2 (sST2) and Gal-3 for HFrEF. Conclusion: We found that the number of circulating CD31+/annexin V+ MVs may improve a predictive capacity for conventional HF biomarkers.

Circulating microparticles as biomarkers of stroke: A focus on the value of endothelial- and platelet-derived microparticles

Stroke is one of the leading causes of mortality and disability worldwide. Numerous pathophysiological mechanisms involving blood vessels, coagulation and inflammation contribute to the vascular occlusion. Perturbations in these pathways can be detected by numerous methods including changes in endoplasmic membrane remodeling and rearrangement leading to the shedding of microparticles (MPs) from various cellular origins in the blood. MPs are small membrane-derived vesicles that are shed from nearly all cells in the body in resting state or upon stimulation. MPs act as biological messengers to transfer information to adjacent and distant cells thus regulating various biological processes. MPs may be important biomarkers and tools for the identification of the risk and diagnosis of cerebrovascular diseases. Endothelial activation and dysfunction and altered thrombotic responses are two of the main features predisposing to stroke. Endothelial MPs (EMPs) have been recognized as both biomarkers and effectors of endothelial cell activation and injury while platelet-derived MPs (PMPs) carry a strong procoagulant potential and are activated in thrombotic states. Therefore, we reviewed here the role of EMPs and PMPs as biomarkers of stroke. Most studies reported high circulating levels of EMPs and PMPs in addition to other cell origins in stroke patients and have been linked to stroke severity, the size of infarction, and prognosis. The identification and quantification of EMPs and PMPs may thus be useful for the diagnosis and management of stroke.

Effects of acute insulin-induced hypoglycaemia on endothelial microparticles in adults with and without type 2 diabetes

AIMS

To assess whether endothelial microparticles (EMPs), novel surrogate markers of endothelial injury and dysfunction, are differentially produced in response to acute insulin-induced hypoglycaemia in adults with and without type 2 diabetes.

MATERIALS AND METHODS

A prospective, parallel study was conducted in individuals with type 2 diabetes (n = 23) and controls (n = 22). Hypoglycaemia (<2.2 mmoL/L: <40 mg/dL) was achieved by intravenous infusion of soluble insulin. Blood samples were collected at baseline and at 0, 30, 60, 120, 240 minutes and 24 hours after hypoglycaemia and analysed for CD31⁺ (platelet endothelial cell adhesion molecule-1), CD54⁺ (intercellular adhesion molecule 1), CD62-E⁺ (E-selectin), CD105⁺ (endoglin), CD106⁺ (vascular cell adhesion molecule 1) and CD142⁺ (tissue factor) EMPs by flow cytometry. The peak elevations (% rise from 0 minutes after hypoglycaemia) in EMP within 240 minutes after insulin-induced hypoglycaemia were modelled using a regression model, with adjustment for relevant covariates. All EMPs were expressed as percentage from 0 minutes hypoglycaemia for each time point and total areas under the curve (AUC_0min-24h ) were calculated.

RESULTS

Following insulin-induced hypoglycaemia, levels of circulating EMPs were maximal at 240 minutes (P < 0.001) and returned to baseline values within 24 hours for both groups. The peak elevations (% rise from 0 minutes following hypoglycaemia) seen in CD31⁺ , CD54⁺ , CD62-E⁺ , CD105⁺ and CD142⁺ EMPs within 240 minutes were associated with diabetes status after adjustments for all relevant covariates. Individuals with type 2 diabetes showed increased CD31⁺ EMPs AUC_0min-24h (P = 0.014) and CD105⁺ EMPs AUC_0min-24h (P = 0.006) compared with controls, but there were no differences for CD54⁺ (P = 0.91), CD62-E⁺ (P = 0.14), CD106⁺ (P = 0.36) or CD142⁺ (P = 0.77) EMPs AUC_0min-24h .

CONCLUSIONS

The associations between peak elevations within 240 minutes after insulin-induced hypoglycaemia for CD31⁺ , CD54⁺ , CD62-E⁺ , CD105⁺ and CD142⁺ and diabetes status indicate that the assessment of a panel of EMPs within this timeframe would identify a hypoglycaemic event in this population. The greater overall responses over time (AUCs) for apoptosis-induced CD31⁺ and CD105⁺ EMPs suggest that hypoglycaemia exerts greater endothelial stress in type 2 diabetes.

Short-term exercise training reduces glycaemic variability and lowers circulating endothelial microparticles in overweight and obese women at elevated risk of type 2 diabetes

Exercise is recognized as a frontline therapy for the prevention and treatment of type 2 diabetes (T2D) but the optimal type of exercise is not yet determined. We compared the effects of high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) for improvement of continuous glucose monitoring (CGM)-derived markers of glycaemic variability, and biomarkers of endothelial cell damage (CD31+ and CD62+ endothelial microparticles (EMPs)) within a population at elevated risk of developing T2D. Fifteen inactive overweight or obese women were randomized to 2 weeks (10-sessions) of progressive HIIT (n = 8, 4-10X 1-min @ ∼90% peak heart rate, 1-min rest periods) or MICT (n = 7, 20-50 min of continuous activity at ∼65% peak heart rate). Prior and three days post-training, fasting blood samples were collected. Both HIIT and MICT improved glycaemic variability as measured by CGM standard deviation (HIIT: 0.82 ± 0.39 vs. 0.72 ± 0.33 mmol/L; MICT: 0.82 ± 0.19 vs. 0.62 ± 0.16 mmol/L, pre vs. post) and mean amplitude of glycaemic excursions (MAGE; HIIT: 1.98 ± 0.81 vs. 1.41 ± 0.90; MICT; 1.98 ± 0.43 vs. 1.65 ± 0.48, pre vs. post) with no difference between groups. CD62+ EMPs were lower following HIIT (187.7 ± 65 vs. 174.9 ± 55, pre vs. post) and MICT (170 ± 60 vs. 160.3 ± 59, pre vs. post) with no difference between groups. There was no change in 24-h mean glucose or CD31+ EMPs. Two weeks of both HIIT or MICT similarly decreased glycaemic variability and CD62+ EMPs in overweight/obese women at elevated risk of T2D.

Increased circulating microparticles in streptozotocin-induced diabetes propagate inflammation contributing to microvascular dysfunction

KEY POINTS

Circulating microparticles (MPs) are elevated in many cardiovascular diseases and have been considered as biomarkers of disease prognosis; however, current knowledge of MP functions has been mainly derived from in vitro studies and their precise impact on vascular inflammation and disease progression remains obscure. Using a diabetic rat model, we identified a >130-fold increase in MPs in plasma of diabetic rats compared to normal rats, the majority of which circulated as aggregates, expressing multiple cell markers and largely externalized phosphatidylserine; vascular images illustrate MP biogenesis and their manifestations in microvessels of diabetic rats. Using combined single microvessel perfusion and systemic cross-transfusion approaches, we delineated how diabetic MPs propagate inflammation in the vasculature and transform normal microvessels into an inflammatory phenotype observed in the microvessels of diabetic rats. Our observations derived from animal studies resembling conditions in diabetic patients, providing a mechanistic insight into MP-mediated pathogenesis of diabetes-associated multi-organ microvascular dysfunction.

ABSTRACT

In various cardiovascular diseases, microparticles (MPs), the membrane-derived vesicles released during cell activation, are markedly increased in the circulation. These MPs have been recognized to play diverse roles in the regulation of cellular functions. However, current knowledge of MP function has been largely derived from in vitro studies. The precise impact of disease-induced MPs on vascular inflammation and disease progression remains obscure. In this study we investigated the biogenesis, profile and functional roles of circulating MPs using a streptozotocin-induced diabetic rat model with well-characterized microvascular functions. Our study revealed a >130-fold increase in MPs in the plasma of diabetic rats compared to normal rats. The majority of these MPs originate from platelets, leukocytes and endothelial cells (ECs), and circulate as aggregates. Diabetic MPs show greater externalized phosphatidylserine (PS) than normal MPs. When diabetic plasma or isolated diabetic MPs were perfused into normal microvessels or systemically transfused into normal rats, MPs immediately adhered to endothelium and subsequently mediated leukocyte adhesion. These microvessels then exhibited augmented permeability responses to inflammatory mediators, replicating the microvascular manifestations observed in diabetic rats. These effects were abrogated when MPs were removed from diabetic plasma or when diabetic MPs were pre-coated with a lipid-binding protein, annexin V, suggesting externalized PS to be key in mediating MP interactions with endothelium and leukocytes. Our study demonstrated that the elevated MPs in diabetic plasma are actively involved in the propagation of vascular inflammation through their adhesive surfaces, providing mechanistic insight into the pathogenesis of multi-organ vascular dysfunction that commonly occurs in diabetic patients.

Plasma endoglin in Type2 diabetic patients with nephropathy

BACKGROUND

Diabetic nephropathy may be a common complication of diabetes mellitus. Endoglin is glycoprotein located on cell surfaces of endothelial cells and is part of the transforming growth factor beta (TGF- β) receptor. Endoglin expression is enhanced in endothelial cells during injury and inflammation. The aim of this study was to estimate the plasma level of soluble endoglin (sEng) in type 2 diabetic patients (with and without nephropathy). Also to explore its availability as marker for disease progression.

METHODS

In this study, sixty eight patients with type 2 diabetes mellitus (T2DM) were included; the patients were sub-grouped to normoalbuminuria without nephropathy and moderately increased albuminuria (microalbuminuria) with nephropathy groups with 13 individuals as control group. Plasma soluble endoglin level was determined using ELISA technique. Fasting plasma glucose (FPG), glycated haemoglobin (HbA1c), lipid profile, and creatinine were determined using colorimetric assay, whereas glomerular filtration rate (GFR) was calculated.

RESULTS

The plasma level of sEng of both normoalbuminuria group 1 and microalbuminuria group 2 were significantly higher when compared to control group. While, the plasma level of sEng in microalbuminuria group 2 was nonsignificant lower when compared to normoalbuminuria group 1. Also, there was a significant positive association between plasma level of sEng and HbA1c, HDL-C and urinary albumin concentration in normoalbuminuria group.

CONCLUSION

Plasma level of soluble Endoglin is markedly increase prior to alteration in endothelial function, and increases to lesser extent with the developing of diabetic nephropathy which indicated disease progression and development of vascular abnormalities.

The Correlation of Serum Osteoprotegerin with Non-Traditional Cardiovascular Risk Factors and Arterial Stiffness in Patients with Pre-Dialysis Chronic Kidney Disease: Results from the KNOW-CKD Study

BACKGROUND

Osteoprotegerin (OPG) plays protective roles against the development of vascular calcification (VC) which greatly contributes to the increased cardiovascular events in patients with chronic kidney disease (CKD). The present study aimed to find the non-traditional, kidney-related cardiovascular risk factors correlated to serum OPG and the effect of serum OPG on the arterial stiffness measured by brachial ankle pulse wave velocity (baPWV) in patients with the pre-dialysis CKD.

METHODS

We cross-sectionally analyzed the data from the patients in whom baPWV and the serum OPG were measured at the time of enrollment in a prospective pre-dialysis CKD cohort study in Korea.

RESULTS

Along with traditional cardiovascular risk factors such as age, diabetes mellitus, pulse pressure, and baPWV, non-traditional, kidney-related factors such as albuminuria, plasma level of hemoglobin, total CO₂ content, alkaline phosphatase, and corrected calcium were independent variables for serum OPG in multivariate linear regression. Reciprocally, the serum OPG was positively associated with baPWV in multivariate linear regression. The baPWV in the 3rd and 4th quartile groups of serum OPG were higher than that in the 1st quartile group after adjustments by age, sex and other significant factors for baPWV in linear mixed model.

CONCLUSION

Non-traditional, kidney-related cardiovascular risk factors in addition to traditional cardiovascular risk factors were related to serum level of OPG in CKD. Serum OPG level was significantly related to baPWV. Our study suggests that kidney-related factors involved in CKD-specific pathways for VC play a role in the increased secretion of OPG into circulation in patients with CKD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01630486.

Serum biomarkers for diagnosis and prediction of type 1 diabetes

Type 1 diabetes (T1D) culminates in the autoimmune destruction of the pancreatic βcells, leading to insufficient production of insulin and development of hyperglycemia. Serum biomarkers including a combination of glucose, glycated molecules, C-peptide, and autoantibodies have been well established for the diagnosis of T1D. However, these molecules often mark a late stage of the disease when ∼90% of the pancreatic insulin-producing β-cells have already been lost. With the prevalence of T1D increasing worldwide and because of the physical and psychological burden induced by this disease, there is a great need for prognostic biomarkers to predict T1D development or progression. This would allow us to identify individuals at high risk for early prevention and intervention. Therefore, considerable efforts have been dedicated to the understanding of disease etiology and the discovery of novel biomarkers in the last few decades. The advent of high-throughput and sensitive "-omics" technologies for the study of proteins, nucleic acids, and metabolites have allowed large scale profiling of protein expression and gene changes in T1D patients relative to disease-free controls. In this review, we briefly discuss the classical diagnostic biomarkers of T1D but mainly focus on the novel biomarkers that are identified as markers of β-cell destruction and screened with the use of state-of-the-art "-omics" technologies.

Microvesicles and ectosomes in angiogenesis and diabetes - message in a bottle in the vascular ocean

The pathogenesis of diabetes involves dysregulated gene expression on a pre- and posttranscriptional level. One key mechanism in the development and progression of diabetes is thought being a dysregulation of signalling mediators such as microRNAs. These microRNAs interfere with pathophysiological reactions in diabetes by affecting gene transcription, insulin resistance and endothelial dysfunction. Here, in this current issue, Stępień et al. analysed ectosomal miRNA patterns in patients with type 2 diabetes mellitus (T2DM) using different analytical techniques. The focus of the current analysis was to characterize pro- and anti-angiogenic signalling effects of ectosomal miRNAs revealing important pathophysiologic mechanisms and signalling in T2DM.

Microparticles as new markers of cardiovascular risk in diabetes and beyond

The term microparticle (MP) identifies a heterogeneous population of vesicles playing a relevant role in the pathogenesis of vascular diseases, cancer and metabolic diseases such as diabetes mellitus. MPs are released by virtually all cell types by shedding during cell growth, proliferation, activation, apoptosis or senescence processes. MPs, in particular platelet- and endothelial-derived MPs (PMPs and EMPs), are increased in a wide range of thrombotic disorders, with an interesting relationship between their levels and disease pathophysiology, activity or progression. EMP plasma levels have been associated with several cardiovascular diseases and risk factors. PMPs are also shown to be involved in the progressive formation of atherosclerotic plaque and development of arterial thrombosis, especially in diabetic patients. Indeed, diabetes is characterised by an increased procoagulant state and by a hyperreactive platelet phenotype, with enhanced adhesion, aggregation, and activation. Elevated MP levels, such as TF+ MPs, have been shown to be one of the procoagulant determinants in patients with type 2 diabetes mellitus. Atherosclerotic plaque constitutes an opulent source of sequestered MPs, called “plaque” MPs. Otherwise, circulating MPs represent a TF reservoir, named “blood-borne” TF, challenging the dogma that TF is a constitutive protein expressed in minute amounts. “Blood-borne” TF is mainly harboured by PMPs, and it can be trapped within the developing thrombus. MP detection and enumeration by polychromatic flow cytometry (PFC) have opened interesting perspectives in clinical settings, particularly for the evaluation of MP numbers and phenotypes as independent marker of cardiovascular risk, disease and outcome in diabetic patients.

Circulating microparticles levels are increased in patients with diabetic kidney disease: A case-control research

BACKGROUND

Type 2 diabetes mellitus (T2DM) is associated with chronic lowgrade inflammation. Microparticles (MPs) are extracellular microvesicles released during apoptosis and cellular activation. The MP's pro-coagulant and pro-inflammatory activities are involved in endothelial dysfunction observed in T2DM patients. This study aimed to evaluate the circulating MPs profile in T2DM patients with diabetic kidney disease (DKD) and correlate it with clinical and laboratorial parameters.

METHODS

MPs derived from platelets (PMPs), leukocytes (LMPs), endothelial cells (EMPs), and expressing tissue factor (TFMPs) were measured by flow cytometry, in plasma of 39 DKD patients and 30 non-diabetic controls.

RESULTS

We observed higher PMPs, LMPs, EMPs, and TFMPs (all p<0.0001) levels in case group as compared to controls. For patients with DKD, circulating MPs levels were influenced by gender, but not by obesity status nor by T2DM onset. Fasting glucose and 25-hydroxyvitamin D levels showed correlation with circulating MPs levels in both groups.

CONCLUSIONS

These results suggest that type 2 diabetes mellitus patients with DKD presented higher circulating MPs levels - PMPs, LMPs, EMPs, and TFMPs - which correlated with metabolic alterations.

Cardiac biomarkers in diabetes mellitus: New dawn for risk stratification?

Type 2 diabetes mellitus (T2DM) remains a leading cause of cardiovascular (CV) events and diseases worldwide. The aim of the review is to summarize our knowledge regarding clinical implementation of the biomarker-based strategy of the CV risk assessment in T2DM patient population. There is large body of evidence regarding use of the cardiac biomarkers to risk stratification at higher CV risk individuals who belongs to general population and cohort with established CV disease. Although T2DM patients have higher incidence of macrovascular and microvascular CV complications than the general population, whether cardiac biomarkers would be effective to risk stratification of the T2DM is not fully understood. The role of natriuretic peptides, galectin-3, interleukins, growth differentiation factor-15, as well as biomarkers of endothelial dysfunction are widely discussed. In conclusion, future directions, which associate with discovering of novel biomarkers and their best combinations to provide additional predictive information beyond other traditional CV risk factors, are discussed.

Endothelial progenitor cells dysfunction and impaired tissue reparation: The missed link in diabetes mellitus development

Diabetes mellitus (DM) is considered a leading cause of premature cardiovascular (CV) mortality and morbidity in general population and in individuals with known CV disease. Recent animal and clinical studies have shown that reduced number and weak function of endothelial progenitor cells (EPCs) may not only indicate to higher CV risk, but contribute to the impaired heart and vessels reparation in patients with DM. Moreover, EPCs having a protective impact on the vasculature may mediate the functioning of other organs and systems. Therefore, EPCs dysfunction is probably promising target for DM treatment strategy, while the role of restoring of EPCs number and functionality in CV risk diminish and reduce of DM-related complications is not fully clear. The aim of the review is summary of knowledge regarding EPCs dysfunction in DM patients.

Microparticles in Chronic Heart Failure

Heart failure (HF) continues to have a sufficient impact on morbidity, mortality, and disability in developed countries. Growing evidence supports the hypothesis that microparticles (MPs) might contribute to the pathogenesis of the HF development playing a pivotal role in the regulation of the endogenous repair system, thrombosis, coagulation, inflammation, immunity, and metabolic memory phenomenon. Therefore, there is a large body of data clarifying the predictive value of MP numerous in circulation among subjects with HF. Although the determination of MP signature is better than measurement of single MP circulating level, there is not yet close confirmation that immune phenotype of cells produced MPs are important for HF prediction and development. The aim of the chapter is to summarize knowledge regarding the role of various MPs in diagnosis and prognosis of HF. The role of MPs as a delivery vehicle for drugs attenuated cardiac remodeling is considered.

Microparticle subpopulations are potential markers of disease progression and vascular dysfunction across a spectrum of connective tissue disease

Objective

Microparticles (MPs) are membrane-bound vesicles derived from vascular and intravascular cells such as endothelial cells (EMPs) and platelets (PMPs). We investigated EMP and PMP numbers across a spectrum of autoimmune rheumatic diseases (AIRDs) with the aim of comparing the levels of, and relationship between, EMPs and PMPs.

Methods

Patients with Systemic Lupus Erythematosus (SLE) (n = 24), Systemic Sclerosis (SSc) (n = 24), Primary Raynauds Phenomenon (RP) (n = 17) and “other CTD” (n = 15) (Primary Sjogrens Syndrome, UCTD or MCTD) as well as 15 healthy controls were recruited. EMPs and PMPs were quantified using flow cytometry. Associations between MP levels and objective functional vascular assessments were evaluated.

Results

SLE patients had significantly higher EMPs compared with healthy controls and SSc patients. Higher PMP levels were noted in SSc and primary RP when compared to healthy controls and ‘other CTD’ patients. A modest correlation was noted between EMP and PMP levels in healthy controls (Spearman r = 0.6, p = 0.017). This relationship appeared stronger in SLE (r = 0.72, p < 0.0001) and other CTD patients (r = 0.75, p < 0.0001). The association between EMPs and PMPs was notably less strong in SSc (r = 0.45, p = 0.014) and RP (r = 0.37, p = 0.15). A significantly lower EMP/PMP ratio was detected in SSc/RP patients in comparison to both healthy controls and SLE/other CTD patients. Higher EMP and PMP levels were associated with higher digital perfusion following cold challenge in SSc. In contrast, higher PMP (but not EMP) levels were associated with lower digital perfusion at both baseline and following cold challenge in primary RP. Higher PMP levels were associated with greater endothelial-independent dilation in patients with SLE.

Conclusion

MP populations differ across the spectrum of AIRDS, possibly reflecting differences in vascular cell injury and activation. MP levels are associated with functional assessments of vascular function and might have a role as novel vascular biomarkers in AIRDs.

Significance and innovations

Levels of circulating endothelial and platelet microparticles differ between SSc/primary RP compared with SLE and other CTDs (UCTD, MCTD and Primary Sjogrens). MP release may occur within different vascular sites across these disease groups (macrovascular and microvascular).

The association between circulating MP levels and objective assessment of macro- and microvascular dysfunction within these disease areas suggests that MPs might have a useful role as novel circulating biomarkers of vascular disease within the CTDs.

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Levels of circulating EMPs and PMPs differ between SSc/primary RP compared with other CTDs including SLE.

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Circulating MP levels are associated with objective assessments of macro- and microvascular dysfunction.

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MPs may have a useful role as novel circulating biomarkers of vascular disease within the CTDs.

Endothelial Microparticles Act as Novel Diagnostic and Therapeutic Biomarkers of Diabetes and Its Complications: A Literature Review

Diabetes mellitus- (DM-) related vascular diseases attract increased attention due to their high morbidity and mortality. The incidence of obesity, atherosclerosis, coronary heart disease, hypertension, and dyslipidemia is significantly higher in DM patients, with an earlier onset and faster progression compared with non-DM patients. DM-related vascular diseases including macrovascular and microvascular complications are characterized by endothelial dysfunction. Therefore, a better understanding of the etiology and mechanisms of endothelial dysfunction is important for the diagnosis and treatment of DM. Endothelial microparticles (EMPs) are new diagnostic and therapeutic targets and biomarkers in DM-related vascular disease. Circulating EMPs containing biologically active substances act as intercellular signals under physiological and pathological conditions. They serve as biological markers of altered vascular endothelium and reflect the pathological progression and diminished endothelial function of blood vessels. Recent evidence suggests that the plasma level of EMPs is significantly higher in DM patients than in healthy population and is significantly correlated with DM-related complications. These observations have prompted speculation that EMPs play a crucial role in the pathophysiology of DM. This review summarizes the known and potential roles of EMPs in the diagnosis, staging, treatment, and clinical prognosis of DM and related vascular diseases.

Circulating endothelial-derived apoptotic microparticles and insulin resistance in non-diabetic patients with chronic heart failure

BACKGROUND

The objective of this study was to assess the relationship between insulin resistance and apoptotic endothelial-derived microparticles (EMPs) in patients with chronic heart failure (CHF).

METHODS

The study involved 300 CHF patients (186 males) aged 48-62 years with angiographically proven coronary artery disease and/or previously defined myocardial infarction. Insulin resistance was assessed by the homeostasis model assessment for insulin resistance (HOMA-IR). EMPs phenotype was determined by flow cytofluorometry.

RESULTS

Depending on HOMA-IR cut-off point (over and <2.77 mmol/L×μU/mL) all patients were divided into two cohorts with (n=171) or without (n=129) IR, respectively. Circulating EMPs were higher in CHF patients with IR than in patients without IR. Interestingly, EMPs were directly related to NYHA functional class of CHF, HOMA-IR, NT-pro-BNP, hs-CRP and BMI. There was a significant association between the level of EMPs and HbA1c, gender (r=0.318, p<0.001 for male), age and smoking. On univariate and multivariate regression analysis we found that the NYHA class of CHF,NT-pro-BNP, hs-CRP, and left ventricular ejection fraction (LVEF) appeared to be independent predictors of increased circulatory apoptotic EMPs. The addition of HOMA-IR to the standard model (NYHA class CHF) improved the relative IDI by 19.9% for increased EMPs. For category-free NRI, 10% of events and 24% of non-events were correctly reclassified by the addition of HOMA-IR to the standard model for increased circulating EMPs.

CONCLUSIONS

IR may be a contributing factor increasing circulating levels of apoptotic EMPs in non-diabetic CHF patients.

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 (R(2) = 0.26; P = 0.001), obesity (R(2) = 0.22; P = 0.001), previous MI (R(2) = 0.17; P = 0.012), galectin-3 (R(2) = 0.67; P = 0.012), CD31(+)/annexin V(+) EMPs (R(2) = 0.11; P = 0.001), NT-proBNP (R(2) = 0.11; P = 0.046), CD14(+) CD309(+) cells (R(2) = 0.058; P = 0.001), and CD14(+) СD309(+) Tie-2(+) cells (R(2) = 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.