Microvesicles and diabetic complications--novel mediators, potential biomarkers and therapeutic targets

EVs-miR-17-5p attenuates the osteogenic differentiation of vascular smooth muscle cells potentially via inhibition of TGF-β signaling under high glucose conditions

Vascular calcification, which is a major complication of diabetes mellitus, is an independent risk factor for cardiovascular disease. Osteogenic differentiation of vascular smooth muscle cells (VSMCs) is one of the key mechanisms underlying vascular calcification. Emerging evidence suggests that macrophage-derived extracellular vesicles (EVs) may be involved in calcification within atherosclerotic plaques in patients with diabetes mellitus. However, the role of macrophage-derived EVs in the progression of vascular calcification is largely unknown. In this study, we investigated whether macrophage-derived EVs contribute to the osteogenic differentiation of VSMCs under high glucose conditions. We isolated EVs that were secreted by murine peritoneal macrophages under normal glucose (EVs-NG) or high glucose (EVs-HG) conditions. miRNA array analysis in EVs from murine macrophages showed that miR-17-5p was significantly increased in EVs-HG compared with EVs-NG. Prediction analysis with miRbase identified transforming growth factor β receptor type II (TGF-β RII) as a potential target of miR-17-5p. EVs-HG as well as miR-17-5p overexpression with lipid nanoparticles inhibited the gene expression of Runx2, and TGF-β RII. Furthermore, we demonstrated that VSMCs transfected with miR-17-5p mimic inhibited calcium deposition. Our findings reveal a novel role of macrophage-derived EVs in the negative regulation of osteogenic differentiation in VSMCs under high glucose conditions.

Detection and characterization of circulating microvesicles containing Shiga toxin type 2 in a rat model of Hemolytic Uremic Syndrome

Shiga toxin producing Escherichia coli (STEC) are foodborne pathogens that release Shiga toxin (Stx), virulence factor responsible for the development of Hemolytic Uremic Syndrome (HUS). Stx causes endothelial cell damage, which leads to platelets deposition and thrombi formation within the microvasculature. It has been described that Stx activates blood cells and induces the shedding of proinflammatory and prothrombotic microvesicles (MVs) containing the toxin. In this sense, it has been postulated that MVs containing Stx2 (MVs-Stx2+) can contribute to the physiopathology of HUS, allowing Stx2 to reach the target organs while evading the immune system. In this work, we propose that circulating MVs-Stx2+ can be a potential biomarker for the diagnosis and prognosis of STEC infections and HUS progression. We developed a rat HUS model by the intraperitoneal injection of a sublethal dose of Stx2 and observed: decrease in body weight, increase of creatinine and urea levels, decrease of creatinine clearance and histological renal damages. After characterization of renal damages, we investigated circulating total MVs and MVs-Stx2+ by flow cytometry at different times after Stx2 injection. Additionally, we evaluated the correlation of biochemical parameters such as creatinine and urea in plasma with MVs-Stx2+. As a result, we found a significant circulation of MVs-Stx2+ at 72 and 96 h after Stx2 injection, nevertheless no correlation with creatinine and urea plasma levels were detected. Our results suggest that MVs-Stx2+ may be an additional biomarker for the characterization and diagnosis of HUS progression. A further analysis is required in order to validate MVs-Stx2+ as biomarker of the disease.

Extracellular vesicles in atherothrombosis: From biomarkers and precision medicine to therapeutic targets

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of global mortality. Extracellular vesicles (EVs) are small phospholipid vesicles that convey molecular bioactive cargoes and play essential roles in intercellular communication and, hence, a multifaceted role in health and disease. The present review offers a glimpse into the current state and up-to-date concepts on EV field. It also covers their association with several cardiovascular risk factors and ischemic conditions, being subclinical atherosclerosis of utmost relevance for prevention. Interestingly, we show that EVs hold promise as prognostic and diagnostic as well as predictive markers of ASCVD in the precision medicine era. We then report on the role of EVs in atherothrombosis, disentangling the mechanisms involved in the initiation, progression, and complication of atherosclerosis and showing their direct effect in the context of arterial thrombosis. Finally, their potential use for therapeutic intervention is highlighted.

Platelets and Their Role in Hemostasis and Thrombosis-From Physiology to Pathophysiology and Therapeutic Implications

Hemostasis is a physiological process critical for survival. Meanwhile, thrombosis is amongst the leading causes of death worldwide, making antithrombotic therapy one of the most crucial aspects of modern medicine. Although antithrombotic therapy has progressed tremendously over the years, it remains far from ideal, and this is mainly due to the incomplete understanding of the exceptionally complex structural and functional properties of platelets. However, advances in biochemistry, molecular biology, and the advent of 'omics' continue to provide crucial information for our understanding of the complex structure and function of platelets, their interactions with the coagulation system, and their role in hemostasis and thrombosis. In this review, we provide a comprehensive view of the complex role that platelets play in hemostasis and thrombosis, and we discuss the major clinical implications of these fundamental blood components, with a focus on hemostatic platelet-related disorders and existing and emerging antithrombotic therapies. We also emphasize a number of questions that remain to be answered, and we identify hotspots for future research.

Extracellular Vesicles as Drivers of Immunoinflammation in Atherothrombosis

Atherosclerotic cardiovascular disease is the leading cause of morbidity and mortality all over the world. Extracellular vesicles (EVs), small lipid-bilayer membrane vesicles released by most cellular types, exert pivotal and multifaceted roles in physiology and disease. Emerging evidence emphasizes the importance of EVs in intercellular communication processes with key effects on cell survival, endothelial homeostasis, inflammation, neoangiogenesis, and thrombosis. This review focuses on EVs as effective signaling molecules able to both derail vascular homeostasis and induce vascular dysfunction, inflammation, plaque progression, and thrombus formation as well as drive anti-inflammation, vascular repair, and atheroprotection. We provide a comprehensive and updated summary of the role of EVs in the development or regression of atherosclerotic lesions, highlighting the link between thrombosis and inflammation. Importantly, we also critically describe their potential clinical use as disease biomarkers or therapeutic agents in atherothrombosis.

Advanced chronic kidney disease is associated with higher serum concentration of monocyte microparticles

Advanced chronic kidney disease is associated with high rates of cardiovascular disease. Considering the crucial role of capillaries in renal function, our study aimed to evaluate microparticles related to vascular physiology examining the link between stages of chronic kidney disease with circulating endothelial (EMP), platelet (PMP) and monocytic (MMP) microparticles. Cross-sectional study with blinded endpoints included subjects of both sexes, aged 40-75 years (n = 247), with established cardiovascular disease (coronary heart disease, ischemic stroke, or peripheral artery disease). They were stratified 1:1 by the presence or absence of decreased glomerular filtration rate (GFR < 60 mL/min/1.73 m²) estimated by the CKD-EPI criteria, and according to the stages of CKD. Microparticles were quantified by flow-cytometry using specific antibodies to identify endothelial, platelet, and monocytic derived microparticles. Higher percentages of circulating MMP (p = 0.036), but not for EMP or PMP, were observed in subjects with reduced GFR. Circulating MMP were also related to the stages of chronic kidney disease (trend analysis across renal stages, p = 0.038). Higher percentages of circulating MMP were found in subjects with reduced GFR, and their percentages were progressively higher according to the stage of chronic renal function.

High levels of endothelial and platelet microvesicles in patients with type 1 diabetes irrespective of microvascular complications

INTRODUCTION

Patients with type 1 diabetes have high risk of developing microvascular complications, and microangiopathy contributes to premature cardiovascular disease in this population. The role that microvesicles (MVs) may play in the development of microangiopathy in type 1 diabetes remains unclear.

MATERIALS AND METHODS

Plasma levels of endothelial MVs (EMVs) and platelet MVs (PMVs) in 130 patients with type 1 diabetes without microangiopathy, 106 patients with microangiopathy and 100 matched healthy controls were analyzed using flow cytometry. MV expression of procoagulant phosphatidylserine (PS) and proinflammatory high mobility group box-1 protein (HMGB1) was also assessed.

RESULTS

Patients with type 1 diabetes had markedly elevated levels of EMVs and PS+ EMVs as well as PMVs and PS+ PMVs compared to healthy controls (p < .001 for all). Furthermore, HMGB1+ EMVs and HMGB1+ PMVs were significantly increased in patients (p < .001 for all). After adjusting for potential confounders, there were no clear differences between patients with or without microvascular complications for any of the MV parameters.

CONCLUSION

Type 1 diabetes is a prothrombotic and proinflammatory disease state that, regardless of the presence of clinical microangiopathy, is associated with elevated levels of plasma MVs, in particular those of an endothelial origin. We have for the first time demonstrated that patients with type 1 diabetes have higher levels of HMGB1+ MVs. HMGB1 is an alarmin with potent proinflammatory effects that drive endothelial dysfunction, and it would therefore be of interest to further study the role of HMGB1+ MVs in the development of macrovascular complications in type 1 diabetes.

The role of genetic factors and monocyte-to-osteoclast differentiation in the pathogenesis of Charcot neuroarthropathy

Charcot neuroarthropathy is a chronic, progressive condition of the skeletal system that affects some patients with diabetic neuropathy. It results in progressive destruction of bones of the foot and disorganisation of pedal joints and ligaments. Effective prevention and treatment for Charcot neuroarthropathy remain a challenge. Currently, there are no reliable repeatable markers to identify patients with diabetes who are at higher risk of developing Charcot neuroarthropathy. The pathogenesis underlying the development of Charcot neuroarthropathy also remains unclear. In this review, we provide an overview of the history, prevalence, symptoms, risk factors, diagnostics and treatment of Charcot neuroarthropathy. We also discuss the potential for OPG and RANKL gene variants to act as predictive markers for the development of Charcot neuroarthropathy. Finally, we summarise the latest research on the role of monocyte-to-osteoclast differentiation in the development of acute Charcot neuroarthropathy.

Current understanding of the role of Adipose-derived Extracellular Vesicles in Metabolic Homeostasis and Diseases: Communication from the distance between cells/tissues

Extracellular vesicles (EVs) including exosomes, microvesicles (MVs), and apoptotic bodies, are small membrane vesicular structures that are released during cell activation, senescence, or programmed cell death, including apoptosis, necroptosis, and pyroptosis. EVs serve as novel mediators for long-distance cell-to-cell communications and can transfer various bioactive molecules, such as encapsulated cytokines and genetic information from their parental cells to distant target cells. In the context of obesity, adipocyte-derived EVs are implicated in metabolic homeostasis serving as novel adipokines. In particular, EVs released from brown adipose tissue or adipose-derived stem cells may help control the remolding of white adipose tissue towards browning and maintaining metabolic homeostasis. Interestingly, EVs may even serve as mediators for the transmission of metabolic dysfunction across generations. Also, EVs have been recognized as novel modulators in various metabolic disorders, including insulin resistance, diabetes mellitus, and non-alcoholic fatty liver disease. In this review, we summarize the latest progress from basic and translational studies regarding the novel effects of EVs on metabolic diseases. We also discuss EV-mediated cross-talk between adipose tissue and other organs/tissues that are relevant to obesity and metabolic diseases, as well as the relevant mechanisms, providing insight into the development of new therapeutic strategies in obesity and metabolic diseases.

Microparticles in systemic sclerosis, targets or tools to control fibrosis: This is the question!

Systemic sclerosis is the main systemic fibrotic disease with unknown etiology characterized by peripheral microvascular injury, activation of immune system, and wide-spread progressive fibrosis. Microparticles can be derived from any cell type during normal cellular differentiation, senescence, and apoptosis, and also upon cellular activation. Carrying along a broad range of surface cytoplasmic and nuclear molecules of originating cells, microparticles are closely implicated in inflammation, thrombosis, angiogenesis, and immunopathogenesis. Recently, microparticles have been proposed as biomarkers of endothelial injury, which is the primary event in the genesis of tissue fibrosis. Microparticles may have a role in fostering endothelial to mesenchymal transition, thus giving a significant contribution to the development of myofibroblasts, the most important final effectors responsible for tissue fibrosis and fibroproliferative vasculopathy. Thanks to potent profibrotic mediators, such as transforming growth factor beta, platelet-derived growth factor, high mobility group box 1 protein, nicotinamide adenine dinucleotide phosphate oxidase 4, and antifibrotic agents, such as matrix metalloproteinases, microparticles may play an opposite role in fibrosis.

Exosome and Biomimetic Nanoparticle Therapies for Cardiac Regenerative Medicine

Exosomes and biomimetic nanoparticles have great potential to develop into a wide-scale therapeutic platform within the regenerative medicine industry. Exosomes, a subgroup of EVs with diameter ranging from 30-100 nm, have recently gained attention as an innovative approach for the treatment of various diseases, including heart disease. Their beneficial factors and regenerative properties can be contrasted with various cell types. Various biomimetic nanoparticles have also emerged as a unique platform in regenerative medicine. Biomimetic nanoparticles are a drug delivery platform, which have the ability to contain both biological and fabricated components to improve therapeutic efficiency and targeting. The novelty of these platforms holds promise for future clinical translation upon further investigation. In order for both exosome therapeutics and biomimetic nanoparticles to translate into large-scale clinical treatment, numerous factors must first be considered and improved. Standardization of different protocols, from exosome isolation to storage conditions, must be optimized to ensure batches are pure. Standardization is also important to ensure no variability in this process across studies, thus making it easier to interpret data across different disease models and treatments. Expansion of clinical trials incorporating both biomimetic nanoparticles and exosomes will require a standardization of fabrication and isolation techniques, as well as stricter regulations to ensure reproducibility across various studies and disease models. This review will summarize current research on exosome therapeutics and the application of biomimetic nanoparticles in cardiac regenerative medicine, as well as applications for exosome expansion and delivery on a large clinical scale.

Relationship between circulating microparticles and hypertension and other cardiac disease biomarkers in the elderly

Background

Microparticles are procoagulant membrane vesicles that play role in endothelium dysfunction pathogenesis and are increased in hypertension, acute/chronic vascular pathological events. Here; we aimed to compare MPs levels of hypertensive geriatric patients with healthy age-match-patients, discuss its availability as a cardiovascular biomarker and investigate its relationship with other inflammatory markers.

Methods

Forty seven hypertensive geriatric patients (M/F;15/32) and 47 healthy controls (M/F;19/28) were included in the study. MPs levels were examined functionally through thrombin generation test (TGT) parameters (MPS Lag time, MPS ETP, MPs Peak, MPS start Tail) and compared with CRP, N/L ratio, ALT, GGT, thrombocyte parameters. Decrease in MPS Lag time, increase in MPS ETS and MPs Peak elevation were accepted as tendency to coagulation which meant an increase in number and function of MPs.

Results

No significant difference was found between 2 groups for MPS tests (MPS Lag time, MPS ETP, MPs Peak, MPS start Tail). Platelet count was significantly higher in hypertensive patient group. There was a negative correlation between age and MPs Peak, MPS Lag time. There was a positive correlation between CRP and MPS ETP, MPs Peak values.

Conclusions

Our present findings might help to understand the hemostasis via TGT parameters, in the elderly. Contribution of MPs to thrombosis tendency seen with aging and increased number of circulating MPs caused by hypertensive endothelial dysfunction must be taken into consideration. MPs might be accepted as vascular inflammation and damage markers and used as follow up tools of medical treatment of vascular inflammation-related diseases.

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.

Extracellular vesicles in atherosclerosis

Extracellular vesicles (EVs), which exist in human blood, are increased in some inflammation-related cardiovascular diseases. EVs are involved in inflammation, immunity, signal transduction, cell survival and apoptosis, angiogenesis, thrombosis, and autophagy, all of which are highly significant for maintaining homeostasis and disease progression. Therefore, EVs are also associated with key steps in atherosclerosis, including cellular lipid metabolism, endothelial dysfunction and vascular wall inflammation, ultimately resulting in vascular remodelling. In this review, we summarize recent studies on EV contents and biological function, focusing on their potential effect in atherosclerosis, including cholesterol metabolism, vascular inflammation, angiogenesis, coagulation and the development of atherosclerotic lesions. EVs may represent potential biomarkers and pharmacological targets for atherosclerotic diseases.

Platelet microparticles contribute to aortic vascular endothelial injury in diabetes via the mTORC1 pathway

Platelet microparticles (PMPs) are closely associated with diabetic macrovascular complications. The present study aimed to investigate the effects of PMPs in diabetes on aortic vascular endothelial injury and to explore the underlying mechanisms. Peritoneal injection of streptozotocin was used to generate a diabetic rat model in vivo, and human umbilical vein endothelial cells (HUVECs) treated with PMPs were used in vitro. PMP levels in the circulation and aorta tissues were time-dependently increased in streptozotocin-induced diabetic rats at weeks 4, 8, and 12 (P < 0.05). Aspirin significantly inhibited the PMP levels at each time point (P < 0.05). In diabetic rats, the endothelial nitric oxide levels were decreased significantly combined with increased endothelial permeability. PMPs were internalized by HUVECs and primarily accumulated around the nuclei. PMPs inhibited endothelial nitric oxide levels to about 50% and caused approximately twofold increase in reactive oxygen species production. Furthermore, PMPs significantly decreased the endothelial glycocalyx area and expression levels of glypican-1 and occludin (P < 0.05). Interestingly, the PMP-induced endothelial injuries were prevented by raptor siRNA and rapamycin. In conclusion, increased PMPs levels contribute to aortic vascular endothelial injuries in diabetes through activating the mTORC1 pathway.

Update of inflammatory proliferative retinopathy: Ischemia, hypoxia and angiogenesis

Diabetic retinopathy (DR) and retinopathy of prematurity (ROP) present two examples of proliferative retinopathy, characterized by the same stages of progression; ischemia of the retinal vessels, leads to hypoxia and to correct the problem there is the setting up of uncontrolled angiogenesis, which subsequently causes blindness or even detachment of the retina. The difference is the following; that DR initiated by the metabolic complications that are due to hyperglycemia, and ROP is induced by overexposure of the neonatal retina to oxygen. In this review, we will demonstrate the physiopathological mechanism of the two forms of proliferative retinopathy DR and ROP, in particular the role of the CD40/CD40L axis and IL-1 on vascular complications and onset of inflammation of the retina, the implications of their effects on the onset of pathogenic angiogenesis, thus understanding the link between platelets and retinal ischemia. In addition, what are the therapeutic targets that could slow its progression?

Dysfunction of Mesenchymal Stem Cells Isolated from Metabolic Syndrome and Type 2 Diabetic Patients as Result of Oxidative Stress and Autophagy may Limit Their Potential Therapeutic Use

Mesenchymal stem cells (MSC) have become a promising tool for therapeutic intervention. Their unique features, including self-renewal, multipotency and immunomodulatory properties draw the worldwide attention of researchers and physicians with respect to their application in disease treatment. However, the environment (so-called niche) from which MSCs are isolated may determine their usefulness. Many studies indicated the involvement of MSCs in ageing and disease. In this review, we have focused on how type 2 diabetes (T2D) and metabolic syndrome (MS) affect MSC properties, and thus limit their therapeutic potential. Herein, we mainly focus on apoptosis, autophagy and mitochondria deterioration processes that indirectly affect MSC fate. Based on the data presented, special attention should be paid when considering autologous MSC therapy in T2D or MS treatments, as their therapeutic potential may be restricted.

Influence of Diabetes on Circulating Apoptotic Microparticles in Patients with Chronic Hepatitis C

BACKGROUND/AIM

Type 2 diabetes mellitus (DM) frequently occurs in patients with chronic hepatitis C (CHC) and is associated with atherosclerosis, in which circulating microparticles (MPs) play an important role. We asked whether the presence of DM affects endothelial-derived (EMPs) and platelet-derived microparticles (PMPs) levels; and whether MPs levels associate with biomarkers of inflammation and oxidative stress in patients with CHC.

MATERIALS AND METHODS

Overall, 136 patients were enrolled in the study, 86 CHC patients (41 with DM with moderate glycemic control), 20 outpatients with DM and 30 controls. Circulating MPs were phenotyped by flow cytometry.

RESULTS

When the MPs levels were analyzed individually in CHC patients, there was a positive association of plasma apoptotic MPs with oxidative stress markers. We report a hitherto undescribed relationship between diabetes prevalence and apoptotic MPs-associated inflammation in patients with CHC.

CONCLUSION

The presence of apoptotic MPs in the plasma of CHC patients, with increased levels being found in patients with DM and moderate glycemic control was herein demonstrated. The simultaneous monitoring of plasma apoptotic MPs, oxidative stress markers and inflammatory biomarkers can be helpful for the cardiovascular disease control in diabetic patients with CHC.

The biology of extracellular microvesicles

The study of extracellular vesicles (EVs) is a rapidly evolving field, owing in large part to recent advances in the realization of their significant contributions to normal physiology and disease. Once discredited as cell debris, these membrane vesicles have now emerged as mediators of intercellular communication by interaction with target cells, drug and gene delivery, and as potentially versatile platforms of clinical biomarkers as a result of their distinctive protein, nucleic acid and lipid cargoes. While there are multiple classes of EVs released from almost all cell types, here we focus primarily on the biogenesis, fate and functional cargoes of microvesicles (MVs). MVs regulate many important cellular processes including facilitating cell invasion, cell growth, evasion of immune response, stimulating angiogenesis, drug resistance and many others.

Microvesicles as Emerging Biomarkers and Therapeutic Targets in Cardiometabolic Diseases

Microvesicles (MVs, also known as microparticles) are small vesicles that originate from plasma membrane of almost all eukaryotic cells during apoptosis or activation. MVs can serve as extracellular vehicles to transport bioactive molecules from their parental cells to recipient target cells, thereby serving as novel mediators for intercellular communication. Importantly, more and more evidence indicates that MVs could play important roles in early pathogenesis and subsequent progression of cardiovascular and metabolic diseases. Elevated plasma concentrations of MVs, originating from red blood cells, leukocytes, platelets, or other organs and tissues, have been reported in various cardiometabolic diseases. Circulating MVs could serve as potential biomarkers for disease diagnosis or therapeutic monitoring. In this review, we summarized recently-published studies in the field and discussed the role of MVs in the pathogenesis of cardiometabolic diseases. The emerging values of MVs that serve as biomarker for non-invasive diagnosis and prognosis, as well as their roles as novel therapeutic targets in cardiometabolic diseases, were also described.

Podocyte-derived microparticles promote proximal tubule fibrotic signaling via p38 MAPK and CD36

Tubulointerstitial fibrosis is a hallmark of advanced diabetic kidney disease that is linked to a decline in renal function, however the pathogenic mechanisms are poorly understood. Microparticles (MPs) are 100–1000 nm vesicles shed from injured cells that are implicated in intercellular signalling. Our lab recently observed the formation of MPs from podocytes and their release into urine of animal models of type 1 and 2 diabetes and in humans with type 1 diabetes. The purpose of the present study was to examine the role of podocyte MPs in tubular epithelial cell fibrotic responses. MPs were isolated from the media of differentiated, untreated human podocytes (hPODs) and administered to cultured human proximal tubule epithelial cells (PTECs). Treatment with podocyte MPs increased p38 and Smad3 phosphorylation and expression of the extracellular matrix (ECM) proteins fibronectin and collagen type IV. MP-induced responses were attenuated by co-treatment with the p38 inhibitor SB202190. A transforming growth factor beta (TGF-β) receptor inhibitor (LY2109761) blocked MP-induced Smad3 phosphorylation and ECM protein expression but not p38 phosphorylation suggesting that these responses occurred downstream of p38. Finally, blockade of the class B scavenger receptor CD36 completely abrogated MP-mediated p38 phosphorylation, downstream Smad3 activation and fibronectin/collagen type IV induction. Taken together our results suggest that podocyte MPs interact with proximal tubule cells and induce pro-fibrotic responses. Such interactions may contribute to the development of tubular fibrosis in glomerular disease.

Endothelial cell-derived microvesicles: potential mediators and biomarkers of pathologic processes

This review focuses on the formation, composition and function of endothelial microvesicles (MV), often called microparticles (MP). MV release is a controlled event and is considered a hallmark of cellular activation or alteration. MV may affect the function of target cells through surface interaction and receptor activation, cellular fusion and the delivery of intravesicular cargo. Endothelial MV are released as a consequence of endothelial activation during inflammation and have been described to affect hemostasis, various aspects of inflammatory reaction, vessel formation, apoptosis and cell survival, endothelial cell differentiation and function. Recent data suggest the potential use of MV in diagnostics, assessment of severity and prediction of outcomes in inflammatory diseases and their utilization as targets, mediators and vectors in therapy.

Pathogenic roles of microvesicles in diabetic retinopathy

Diabetic retinopathy (DR) is a common complication of diabetes and has been recognized as the leading cause of blindness in adults. Several interrelated molecular pathways are involved in the development of DR. Microvesicles (MVs) are cell membrane vesicles, which carry many biologic molecules, such as mRNAs, microRNAs, transcription factors, membrane lipids, membrane receptors, and other proteins. They may be involved in intercellular communication that can promote inflammation, angiogenesis, and coagulation. Recent studies have indicated that changes in the number and composition of MVs may reflect the pathologic conditions of DR. At present, MVs are well recognized as being involved in the pathophysiological conditions of tumors and cardio-metabolic diseases. However, the roles of MVs in DR have yet to be investigated. In this review, we provide an overview of DR-induced microvascular injury that is caused by MVs derived from endothelial and circulating cells, and discuss the possible mechanisms by which MVs can lead to endothelial dysfunction, coagulation and inflammation. In addition, the protective effects of preconditioned MVs and stem cell-derived MVs are also described . Understanding the involvement of MVs in the pathophysiological conditions of DR may provide insight into the disease mechanisms and may suggest novel therapeutic strategies for DR in the future.

Endothelial- and Immune Cell-Derived Extracellular Vesicles in the Regulation of Cardiovascular Health and Disease

Intercellular signaling by extracellular vesicles (EVs) is a route of cell-cell crosstalk that allows cells to deliver biological messages to specific recipient cells. EVs convey these messages through their distinct cargoes consisting of cytokines, proteins, nucleic acids, and lipids, which they transport from the donor cell to the recipient cell. In cardiovascular disease (CVD), endothelial- and immune cell-derived EVs are emerging as key players in different stages of disease development. EVs can contribute to atherosclerosis development and progression by promoting endothelial dysfunction, intravascular calcification, unstable plaque progression, and thrombus formation after rupture. In contrast, an increasing body of evidence highlights the beneficial effects of certain EVs on vascular function and endothelial regeneration. However, the effects of EVs in CVD are extremely complex and depend on the cellular origin, the functional state of the releasing cells, the biological content, and the diverse recipient cells. This paper summarizes recent progress in our understanding of EV signaling in cardiovascular health and disease and its emerging potential as a therapeutic agent.

Circulating microparticles in acute diabetic Charcot foot exhibit a high content of inflammatory cytokines, and support monocyte-to-osteoclast cell induction

Circulating microparticles (MPs) are major mediators in cardiovascular complications of type 2 diabetes (T2D); however, their contribution to Charcot foot (CF) disease is not known. Here, we purified and assessed the origin, concentration and content of circulating MPs from 33 individuals: 11 with T2D and acute CF, 11 T2D patients with equivalent neuropathy and 11 non-diabetic controls. First, we demonstrated that there were no differences in the distribution of MPs of endothelial, platelet origin among the 3 groups. However, MPs from leukocytes and monocytes origin were increased in CF patients. Moreover, we demonstrated that monocytes-derived MPs originated more frequently from intermediate and non-classical monocytes in CF patients. Five cytokines (G-CSF, GM-CSF, IL-1-ra, IL-2 and IL-16) were significantly increased in MPs from acute CF patients. Applying ingenuity pathways analysis, we found that those cytokines interacted well and induced the activation of pathways that are involved in osteoclast formation. Further, we treated THP-1 monocytes and monocytes sorted from healthy patients with CF-derived MPs during their differentiation into osteoclasts, which increased their differentiation into multinucleated osteoclast-like cells. Altogether, our study suggests that circulating MPs in CF disease have a high content of inflammatory cytokines and could increase osteoclast differentiation in vitro.

ROCK-1 mediates diabetes-induced retinal pigment epithelial and endothelial cell blebbing: Contribution to diabetic retinopathy

In diabetic retinopathy, the exact mechanisms leading to retinal capillary closure and to retinal barriers breakdown remain imperfectly understood. Rho-associated kinase (ROCK), an effector of the small GTPase Rho, involved in cytoskeleton dynamic regulation and cell polarity is activated by hyperglycemia. In one year-old Goto Kakizaki (GK) type 2 diabetic rats retina, ROCK-1 activation was assessed by its cellular distribution and by phosphorylation of its substrates, MYPT1 and MLC. In both GK rat and in human type 2 diabetic retinas, ROCK-1 is activated and associated with non-apoptotic membrane blebbing in retinal vessels and in retinal pigment epithelium (RPE) that respectively form the inner and the outer barriers. Activation of ROCK-1 induces focal vascular constrictions, endoluminal blebbing and subsequent retinal hypoxia. In RPE cells, actin cytoskeleton remodeling and membrane blebs in RPE cells contributes to outer barrier breakdown. Intraocular injection of fasudil, significantly reduces both retinal hypoxia and RPE barrier breakdown. Diabetes-induced cell blebbing may contribute to ischemic maculopathy and represent an intervention target.

Urinary Microvesicle-Bound Uromodulin: A Potential Molecular Biomarker in Diabetic Kidney Disease

This study was designed to investigate the changes of urinary microvesicle-bound uromodulin and total urinary uromodulin levels in human urine and the correlations with the severity of diabetic kidney disease (DKD). 31 healthy subjects without diabetes and 100 patients with type 2 diabetes mellitus (T2DM) were included in this study. The patients with T2DM were divided into three groups based on the urinary albumin/creatinine ratio (UACR): normoalbuminuria group (DM, n = 46); microalbuminuria group (DN1, n = 32); and macroalbuminuria group (DN2, n = 22). We use a specific monoclonal antibody AD-1 to capture the urinary microvesicles. Urinary microvesicle-bound uromodulin and total urinary uromodulin levels were determined by enzyme-linked immunosorbent assay (ELISA). Our results showed that the levels of urinary microvesicle-bound uromodulin in DN1 and DN2 groups were significantly higher than those in control group and DM group (P < 0.01). Multiple stepwise linear regression analysis showed that UACR was independent determinant for urinary microvesicle-bound uromodulin (P < 0.05) but not for total urinary uromodulin. These findings suggest that the levels of urinary microvesicle-bound uromodulin are associated with the severity of DKD. The uromodulin in urinary microvesicles may be a specific marker of DKD and potentially may be used to predict the onset and/or monitor the progression of DKD.

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.

Glucose and angiotensin II-derived endothelial extracellular vesicles regulate endothelial dysfunction via ERK1/2 activation

In various diseases, including diabetes, extracellular vesicles (EVs) have been detected in circulation and tissues. EVs are small membrane vesicles released from various cell types under varying conditions. Recently, endothelial cell-derived EVs (EEVs) were identified as a marker of endothelial dysfunction in diabetes, but the ensuing mechanisms remain poorly understood. In this study, we dissected the ensuing pathways with respect to nitric oxide (NO) production under the condition of type 2 diabetes. Human umbilical vein endothelial cells (HUVECs) were stimulated with glucose alone and with glucose in combination with angiotensin II (Ang II) for 48 h. In supernatants from glucose + Ang II-stimulated HUVECs, release of EEVs was assessed using Western blotting with an anti-CD144 antibody. EEV release was significantly increased after stimulation of HUVECs, and high glucose + Ang II-derived EEVs impaired ACh-induced vascular relaxation responses and NO production in mice aortic rings. Furthermore, high glucose + Ang II-derived EEVs induced ERK1/2 signalling and decreased endothelial NO synthase (eNOS) protein expression in mice aortas. Furthermore, in the presence of the MEK/ERK1/2 inhibitor PD98059, high glucose plus Ang II treatment stimulated EEVs in HUVECs and those EEVs prevented the impairments of ACh-induced relaxation and NO production in mice aortas. These data strongly indicate that high glucose and Ang II directly affect endothelial cells and the production of EEVs; the resultant EEVs aggravate endothelial dysfunction by regulating eNOS protein levels and ERK1/2 signalling in mice aortas.

The signature of circulating microparticles in heart failure patients with metabolic syndrome

The role of pattern of circulating endothelial cell-derived microparticles, platelet-derived microparticles (PMPs), and monocyte-derived microparticles (MMPs) in metabolic syndrome (MetS) patients with chronic heart failure (CHF) is not still understood. The aim of the study was to investigate a pattern of circulating microparticles (MPs) in MetS patients with CHF in relation to neurohumoral and inflammatory activation. The study retrospectively involved 101 patients with MetS and 35 healthy volunteers. Biomarkers were measured at baseline of the study. The results of the study have shown that numerous circulating PMPs- and MMPs in subjects with MetS (with or without CHF) insufficiently distinguished from level obtained in healthy volunteers. We found elevated level of CD31+/annexin V+ MPs in association with lower level of CD62E+ MPs. Therefore, we found that biomarkers of biomechanical stress serum N-terminal brain natriuretic peptide and inflammation (high-sensitive C-reactive protein ,osteoprotegerin) remain statistically significant predictors for decreased CD62E+ to CD31+/annexin V+ ratio in MetS patients with CHF. In conclusion, decreased CD62E+ to CD31+/annexin V+ ratio reflected that impaired immune phenotype of MPs may be discussed as a surrogate marker of CHF development in MetS population.

Translocation of Endogenous Danger Signal HMGB1 From Nucleus to Membrane Microvesicles in Macrophages

High mobility group box 1 (HMGB1) is a nuclear protein that can be released from activated or dead cells. Extracellular HMGB1 can serve as a "danger signal" and novel cytokine that mediates sterile inflammation. In addition to its soluble form, extracellular HMGB1 can also be carried by membrane microvesicles. However, the cellular mechanisms responsible for nuclear HMGB1 translocation to the plasma membrane and release onto membrane microvesicles have not been investigated. Tobacco smoking is a major cause of sterile inflammation in many diseases. Smoking also increases blood levels of HMGB1. In this study, we found that exposure of macrophages to tobacco smoke extract (TSE) stimulated HMGB1 expression, redistribution, and release into the extracellular milieu both as a soluble molecule and, surprisingly, as a microvesicle-associated form (TSE-MV). Inhibition of chromosome region maintenance-1 (CRM1), a nuclear exporter, attenuated TSE-induced HMGB1 redistribution from the nucleus to the cytoplasm, and then its release on TSE-MVs. Our study demonstrates a novel mechanism for the translocation of nuclear HMGB1 to the plasma membrane, and then its release in a microvesicle-associated form. J. Cell. Physiol. 231: 2319-2326, 2016. © 2016 Wiley Periodicals, Inc.

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.

Umbilical cord mesenchymal stem cells derived extracellular vesicles can safely ameliorate the progression of chronic kidney diseases

Background

Bio-products from stem/progenitor cells, such as extracellular vesicles, are likely a new promising approach for reprogramming resident cells in both acute and chronic kidney disease. Forty CKD patients stage III and IV (eGFR 15–60 mg/ml) have been divided into two groups; twenty patients as treatment group “A” and twenty patients as a matching placebo group “B”. Two doses of MSC-derived extracellular vesicles had been administered to patients of group “A”. Blood urea, serum creatinine, urinary albumin creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) have been used to assess kidney functions and TNF-α, TGF-β1 and IL-10 have been used to assess the amelioration of the inflammatory immune activity.

Results

Participants in group A exhibited significant improvement of eGFR, serum creatinine level, blood urea and UACR. Patients of the treatment group “A” also exhibited significant increase in plasma levels of TGF-β1, and IL-10 and significant decrease in plasma levels of TNF-α. Participants of the control group B did not show significant improvement in any of the previously mentioned parameters at any time point of the study period.

Conclusion

Administration of cell-free cord-blood mesenchymal stem cells derived extracellular vesicles (CF-CB-MSCs-EVs) is safe and can ameliorate the inflammatory immune reaction and improve the overall kidney function in grade III-IV CKD patients.

Microvesicles in Autoimmune Diseases

During apoptosis or activation, cells can release a subcellular structure, called a membrane microvesicle (also known as microparticle) into the extracellular environment. Microvesicles bud-off as a portion of cell membrane with its associated proteins and lipids surrounding a cytosolic core that contains intracellular proteins, lipids, and nucleic acids (DNA, RNA, siRNA, microRNA, lncRNA). Biologically active molecules on the microvesicle surface and encapsulated within can act on recipient cells as a novel mode of intercellular communication. Apoptosis has long been known to be involved in the development of diseases of autoimmunity. Abnormally persistent microvesicles, particularly apoptotic microvesicles, can accelerate autoimmune responses locally in specific organs and tissues as well as systemically. In this review, we focus on studies implicating microvesicles in the pathogenesis of autoimmune diseases and their complications.

Microparticle Shedding by Erythrocytes, Monocytes and Vascular Smooth Muscular Cells Is Reduced by Aspirin in Diabetic Patients

INTRODUCTION AND OBJECTIVES

Diabetes mellitus is associated with an enhanced risk for cardiovascular disease and its prevalence is increasing. Diabetes induces metabolic stress on blood and vascular cells, promoting platelet activation and vascular dysfunction. The level of vascular cell activation can be measured by the number and phenotype of microparticles found in the circulation. The aim of this study was to investigate the effect of a platelet-inhibitory dose of aspirin on the number and type of microparticles shed to the circulation.

METHODS

Forty-three diabetic patients were enrolled in the study and received a daily dose of 100mg of aspirin for 10 days to cover the average platelet life-span in the circulation. Before and after the intervention period, circulating microparticles were characterized and quantified by flow cytometry.

RESULTS

Type 1 diabetic patients had about twice the number of tissue factor-positive circulating microparticles (derived both from platelets and monocytes) and endothelial-derived E-selectin positive microparticles than type 2 diabetic patients. Aspirin therapy significantly inhibited platelets since cyclooxygenase 1 derived thromboxane generation levels were reduced by 99%. Microparticles derived from erythrocytes, activated monocytes, and smooth muscle cells were significantly reduced after 10 days of aspirin administration.

CONCLUSIONS

These results indicate that: a) vascular and blood cells in type 1 diabetic patients are exposed to more sustained stress shown by their specific microparticle origin and levels; b) aspirin therapy inhibits vascular wall cell activation and microparticle shedding, and c) the effects of aspirin are similar in type 1 and 2 diabetes.

Extracellular Vesicles: A New Frontier in Biomarker Discovery for Non-Alcoholic Fatty Liver Disease

In recent years, the global burden of obesity and diabetes has seen a parallel rise in other metabolic complications, such as non-alcoholic fatty liver disease (NAFLD). This condition, once thought to be a benign accumulation of hepatic fat, is now recognized as a serious and prevalent disorder that is conducive to inflammation and fibrosis. Despite the rising incidence of NAFLD, there is currently no reliable method for its diagnosis or staging besides the highly invasive tissue biopsy. This limitation has resulted in the study of novel circulating markers as potential candidates, one of the most popular being extracellular vesicles (EVs). These submicron membrane-bound structures are secreted from stressed and activated cells, or are formed during apoptosis, and are known to be involved in intercellular communication. The cargo of EVs depends upon the parent cell and has been shown to be changed in disease, as is their abundance in the circulation. The role of EVs in immunity and epigenetic regulation is widely attested, and studies showing a correlation with disease severity have made these structures a favorable target for diagnostic as well as therapeutic purposes. This review will highlight the research that is available on EVs in the context of NAFLD, the current limitations, and projections for their future utility in a clinical setting.

Circulating microparticles from diabetic rats impair endothelial function and regulate endothelial protein expression

AIM

Diabetes mellitus increases the risk of cardiovascular disease, which is accompanied by functional and structural changes in the vascular system. Microparticles (MPs) have been described as biological vectors of endothelial dysfunction in other pathologies. However, the molecular mechanisms underlying their formation and signalling are unclear. We investigated the role of MPs derived from streptozotocin (STZ)-induced diabetic rats in endothelial function.

METHODS

Male Wistar rats were injected with STZ to induce diabetes, and MPs isolated from control or STZ-induced diabetic rats were characterized by dot blotting (assessed by CD62P detections), flow cytometry (assessed by annexin V detections) and ELISA. Carotid arteries from rats were incubated with MPs, and expressions of enzymes and endothelium-dependent relaxation were analysed.

RESULTS

The circulating levels of MPs, particularly the levels of platelet-derived microparticles, from diabetic rats were higher than those present in controls. Endothelium-dependent relaxation induced by acetylcholine (ACh) was attenuated in carotid arteries from STZ-induced diabetic rats. Following the incubation of control carotid arteries with MPs isolated from STZ rats, ACh-induced endothelium-dependent relaxation was impaired, but MPs isolated from control rats had no such effect. Furthermore, the effect of MPs was mediated by a decrease in expression of endothelial nitric oxide synthase (eNOS) and the overexpression of caveolin-1.

CONCLUSION

Circulating MPs isolated from STZ-induced diabetic rats induce endothelial dysfunction in carotid arteries and regulate protein expressions of eNOS and caveolin-1. These data advance our understanding of the deleterious effects of circulating MPs observed in disorders with diabetic complications.

Microvesicles and exosomes: new players in metabolic and cardiovascular disease

The past decade has witnessed an exponential increase in the number of publications referring to extracellular vesicles (EVs). For many years considered to be extracellular debris, EVs are now seen as novel mediators of endocrine signalling via cell-to-cell communication. With the capability of transferring proteins and nucleic acids from one cell to another, they have become an attractive focus of research for different pathological settings and are now regarded as both mediators and biomarkers of disease including cardio-metabolic disease. They also offer therapeutic potential as signalling agents capable of targeting tissues or cells with specific peptides or miRNAs. In this review, we focus on the role that microvesicles (MVs) and exosomes, the two most studied classes of EV, have in diabetes, cardiovascular disease, endothelial dysfunction, coagulopathies, and polycystic ovary syndrome. We also provide an overview of current developments in MV/exosome isolation techniques from plasma and other fluids, comparing different available commercial and non-commercial methods. We describe different techniques for their optical/biochemical characterization and quantitation. We also review the signalling pathways that exosomes and MVs activate in target cells and provide some insight into their use as biomarkers or potential therapeutic agents. In summary, we give an updated focus on the role that these exciting novel nanoparticles offer for the endocrine community.

Recent progress on lipid lateral heterogeneity in plasma membranes: From rafts to submicrometric domains

The concept of transient nanometric domains known as lipid rafts has brought interest to reassess the validity of the Singer-Nicolson model of a fluid bilayer for cell membranes. However, this new view is still insufficient to explain the cellular control of surface lipid diversity or membrane deformability. During the past decades, the hypothesis that some lipids form large (submicrometric/mesoscale vs nanometric rafts) and stable (>min vs s) membrane domains has emerged, largely based on indirect methods. Morphological evidence for stable submicrometric lipid domains, well-accepted for artificial and highly specialized biological membranes, was further reported for a variety of living cells from prokaryot es to yeast and mammalian cells. However, results remained questioned based on limitations of available fluorescent tools, use of poor lipid fixatives, and imaging artifacts due to non-resolved membrane projections. In this review, we will discuss recent evidence generated using powerful and innovative approaches such as lipid-specific toxin fragments that support the existence of submicrometric domains. We will integrate documented mechanisms involved in the formation and maintenance of these domains, and provide a perspective on their relevance on membrane deformability and regulation of membrane protein distribution.

β cell membrane remodelling and procoagulant events occur in inflammation-driven insulin impairment: a GLP-1 receptor dependent and independent control

Inflammation and hyperglycaemia are associated with a prothrombotic state. Cell-derived microparticles (MPs) are the conveyors of active procoagulant tissue factor (TF) and circulate at high concentration in diabetic patients. Liraglutide, a glucagon-like peptide (GLP)-1 analogue, is known to promote insulin secretion and β-cell preservation. In this in vitro study, we examined the link between insulin impairment, procoagulant activity and plasma membrane remodelling, under inflammatory conditions. Rin-m5f β-cell function, TF activity mediated by MPs and their modulation by 1 μM liraglutide were examined in a cell cross-talk model. Methyl-β-cyclodextrine (MCD), a cholesterol depletor, was used to evaluate the involvement of raft on TF activity, MP shedding and insulin secretion as well as Soluble N-éthylmaleimide-sensitive-factor Attachment protein Receptor (SNARE)-dependent exocytosis. Cytokines induced a two-fold increase in TF activity at MP surface that was counteracted by liraglutide. Microparticles prompted TF activity on the target cells and a two-fold decrease in insulin secretion via protein kinase A (PKA) and p38 signalling, that was also abolished by liraglutide. Large lipid raft clusters were formed in response to cytokines and liraglutide or MCD-treated cells showed similar patterns. Cells pre-treated by saturating concentration of the GLP-1r antagonist exendin (9-39), showed a partial abolishment of the liraglutide-driven insulin secretion and liraglutide-decreased TF activity. Measurement of caspase 3 cleavage and MP shedding confirmed the contribution of GLP-1r-dependent and -independent pathways. Our results confirm an integrative β-cell response to GLP-1 that targets receptor-mediated signalling and membrane remodelling pointing at the coupling of insulin secretion and inflammation-driven procoagulant events.

Exosomes: emerging roles in communication between blood cells and vascular tissues during atherosclerosis

PURPOSE OF REVIEW

Microvesicles, in general, and exosomes together with their delivered content in particular, are now being widely recognized as key players in atherosclerosis. We have previously reviewed the role of microvesicles in atherosclerosis pathogenesis, diagnosis and therapy. Here, we focus on the roles of exosomes and discuss their emergent role in mediating activation and response to inflammation, vessel infiltration and induction of coagulation. We will finally give an outlook to discuss novel detection techniques and systems biology based data analyses to investigate exosome-mediated cell-to-cell communication.

RECENT FINDINGS

Recent research points to a role of exosomes in delivering apoptotic and inflammatory content between blood cells and vascular cells, with a potential contribution of exosomes secreted by adipose tissue. An atheroprotective role of exosomes in response to coagulation that may contrast with the procoagulatory role of platelet-derived larger microvesicles is envisaged. New detection and separation methods and systems biology techniques are emerging.

CONCLUSION

We project that the development of novel detection, separation and analysis mechanism and systems-based analysis methods will further unravel the paracrine and endocrine 'communication protocol' between cellular players in atherosclerosis, mediating inflammation, oxidative stress and apoptosis.

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

INTRODUCTION

Type two diabetes mellitus (T2DM) remains a leading contributor to cardiovascular mortality worldwide. This study was conducted to investigate the pattern of circulating EMPs in T2DM patients in comparison with MetS subjects.

METHODS

The study retrospectively included 101 patients (54 subjects with T2DM and 47 patients with MetS) and 35 healthy volunteers. All the patients gave written informed consent for participation in the study. Biomarkers were measured at baseline of the study.

RESULTS

There is a significant difference between healthy subjects and patients regarding CD31+/annexin V+ EMPs to CD62E+ EMPs ratio, which reflects impaired phenotype of EMPs. Therefore, CD31+/annexin V+ EMPs to CD62E+ EMPs ratio was found to be higher in the T2DM patients compared to MetS patients. Using multivariate linear regression analyses, independent impact of T2DM (r = 0.40, P = 0.003), OPG (r = 0.37, P = 0.001), hs-CRP (r = 0.347, P = 0.001), and adiponectin (r = 0.33, P = 0.001) on increased CD31+/annexin V+ to CD62E+ ratio of EMPs was determined. Using C-statistics, we found that inflammatory biomarkers (hs-C-reactive protein, osteoprotegerin and adiponectin) added to the base model (T2DM) improved the relative IDI by 12.6 % for increased CD31+/annexin V+ EMPs to CD62E+ EMPs ratio.

CONCLUSION

We found that patients with T2DM and MetS may be distinguished by predominantly appearing phenotypes of circulating EMPs associated with pro-inflammatory cytokine overproduction. Elevated CD31+/annexin V+ EMPs to CD62E+ EMPs ratio is an indicator of impaired immune phenotype of EMPs, which allows determining the pattern of EMPs in dysmetabolic disorder patients.

Obesity reduces the pro-angiogenic potential of adipose tissue stem cell-derived extracellular vesicles (EVs) by impairing miR-126 content: impact on clinical applications

BACKGROUND/OBJECTIVES

Soluble factors and cell-derived extracellular vesicles (EVs) are crucial tissue repair mediators in cell-based therapy. In the present study, we investigate the therapeutic impact of EVs released by adipose tissue-derived stem cells (ASCs) recovered from obese subjects' visceral and subcutaneous tissues.

METHODS

ASCs were recovered from 10 obese (oASCs) and 6 non-obese (nASCs) participants and characterized. In selected experiments, nASCs and oASCs were cultured with palmitic acid (PA) or high glucose (HG), respectively. EVs from obese (oEVs) and non-obese (nEVs) subjects' visceral and subcutaneous ASCs were collected after ultracentrifugation and analyzed for their cargo: microRNA-126 (miR-126), vascular endothelial growth factor (VEGF), and matrix metalloproteinase 2 (MMP-2), and for their biological effects on endothelial cells (ECs). Western blotting analysis and loss- and gain-of function experiments were performed.

RESULTS

oEVs show impaired angiogenic potential compared with nEVs. This effect depends on EV cargo: reduced content of VEGF, MMP-2 and, more importantly, miR-126. We demonstrate, using gain- and loss-of-function experiments, that this reduced miR-126 content leads to Spred1 upregulation and the inhibition of the extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase pathway in ECs. We also show that PA treatment of nASCs translates into the release of EVs that recapitulate oEV cargo. Moreover, HG treatment of oASCs further reduces miR-126 EV content and EV-mediated in vitro angiogenesis. Finally, impaired pro-angiogenic potential is also detected in EVs released from obese subcutaneous adipose tissue-derived ASCs.

CONCLUSIONS

These results indicate that obesity impacts on EV pro-angiogenic potential and may raise concerns about the use of adipose tissue-derived EVs in cell-based therapy in the obese setting.

Human Induced Pluripotent Stem Cell-Derived Microvesicles Transmit RNAs and Proteins to Recipient Mature Heart Cells Modulating Cell Fate and Behavior

Microvesicles (MVs) are membrane-enclosed cytoplasmic fragments released by normal and activated cells that have been described as important mediators of cell-to-cell communication. Although the ability of human induced pluripotent stem cells (hiPSCs) to participate in tissue repair is being increasingly recognized, the use of hiPSC-derived MVs (hiPSC-MVs) in this regard remains unknown. Accordingly, we investigated the ability of hiPSC-MVs to transfer bioactive molecules including mRNA, microRNA (miRNA), and proteins to mature target cells such as cardiac mesenchymal stromal cells (cMSCs), and we next analyzed effects of hiPSC-MVs on fate and behavior of such target cells. The results show that hiPSC-MVs derived from integration-free hiPSCs cultured under serum-free and feeder-free conditions are rich in mRNA, miRNA, and proteins originated from parent cells; however, the levels of expression vary between donor cells and MVs. Importantly, we found that transfer of hiPSC components by hiPSC-MVs impacted on transcriptome and proteomic profiles of target cells as well as exerted proliferative and protective effects on cMSCs, and enhanced their cardiac and endothelial differentiation potential. hiPSC-MVs also transferred exogenous transcripts from genetically modified hiPSCs that opens new perspectives for future strategies to enhance MV content. We conclude that hiPSC-MVs are effective vehicles for transferring iPSC attributes to adult somatic cells, and hiPSC-MV-mediated horizontal transfer of RNAs and proteins to injured tissues may be used for therapeutic tissue repair. In this study, for the first time, we propose a new concept of use of hiPSCs as a source of safe acellular bioactive derivatives for tissue regeneration.