Transplantation of Ex Vivo Expanded Bone Marrow-Derived Endothelial Progenitor Cells Enhances Chronic Venous Thrombus Resolution and Recanalization

miRNA-130 Promotes Migration and Angiogenesis of Endothelial Progenitor Cells Through PI3K/AKT/mTOR Pathways

<sec> <title>Aim:</title> In this study, we aimed to investigate the effects and mechanisms of miRNA-130a in human endothelial progenitor cells (EPCs) involved in Deep vein thrombosis (DVT). </sec> <sec> <title>Methods:</title> EPCs were isolated and identified by cell morphology and surface marker detection. The effect of miR-130a on the migration, invasion and angiogenesis of EPCs in vitro were also detected. In addition, whether miR-130a is involved in the MMP-1 expression and Akt/PI3K/mTOR signaling pathway was also demonstrated. </sec> <sec> <title>Results:</title> Results suggested that miRNA-130a promotes migration, invasion, and tube formation of EPCs by positively regulating the expression of MMP-1 through Akt/PI3K/mTOR signaling pathway. </sec> <sec> <title>Conclusion:</title> Thus, as a potential therapeutic target, miRNA-130a may play an important role in the treatment of DVT. </sec>

Endothelial progenitor cells and coronary artery disease: Current concepts and future research directions

Vascular injury is a frequent pathology in coronary artery disease. To repair the vasculature, scientists have found that endothelial progenitor cells (EPCs) have excellent properties associated with angiogenesis. Over time, research on EPCs has made encouraging progress regardless of pathology or clinical technology. This review focuses on the origins and cell markers of EPCs, and the connection between EPCs and coronary artery disease. In addition, we summarized various studies of EPC-capturing stents and EPC infusion therapy, and aim to learn from past technology to predict the future.

Endothelial progenitor cells overexpressing platelet derived growth factor-D facilitate deep vein thrombosis resolution

To assess the therapeutic efficacy of PDGF-D-overexpressing endothelial progenitor cells (EPCs) in deep vein thrombosis. Inferior vena cava thrombosis was induced in female Sprague Dawley (SD) rats. Animals were injected via the distal vena cava with EPCs overexpressing PDGF-D after transfection with a lentiviral vector containing the PDGF-D gene. The effect on thrombosis in animals who received EPCs was evaluated using MSB staining, immunohistochemistry, immunofluorescence, and venography; the steady-state mRNA and protein levels of PDGF-D and its receptor (PDGF-Rβ) were determined by RT-PCR and Western blotting, respectively; and the PDGF-D-induced mobilization of circulating EPCs was estimated by flow cytology. Compared with controls, injection of EPCs overexpressing PDGF-D was associated with increased thrombosis resolution; recanalization; PDGF-D and PDGF-Rβ expression; induction of monocyte homing; and mobilization of EPCs to the venous circulation. In a rat model, transplantation of PDGF-D-overexpressing EPCs facilitated the resolution of deep vein thrombosis.

Endothelial progenitor cell-derived exosomes, loaded with miR-126, promoted deep vein thrombosis resolution and recanalization

Background

Deep vein thrombosis (DVT) is caused by blood clotting in the deep veins. Thrombosis resolution and recanalization can be accelerated by endothelial progenitor cells. In this report, we investigated the effects of miR-126-loaded EPC-derived exosomes (miR-126-Exo) on EPCs function and venous thrombus resolution.

Methods

In vitro promotional effect of miR-126-Exo on the migration and tube incorporation ability of EPCs was investigated via transwell assay and tube formation assay. In addition, a mouse venous thrombosis model was constructed and treated with miR-126-Exo to clarify the therapeutic effect of miR-126-Exo by histological analysis. Lastly, this study predicted a target gene of miR-126 using target prediction algorithms and confirmed it by luciferase activity assay, RT-qPCR, and Western blot.

Results

Transwell assay and tube formation assay indicated that miR-126-Exo could enhance the migration and tube incorporation ability of EPCs. Moreover, in vivo study manifested enhanced thrombus organization and recanalization after miR-126-Exo treatment. Meanwhile, we identified that Protocadherin 7 as a target gene of miR-126.

Conclusions

To sum up, our results demonstrated that EPC-derived exosomes loaded with miR-126 significantly promoted thrombus resolution in an animal model of venous thrombosis, indicating exosomes as a promising potential vehicle carrying therapeutic molecules for DVT therapy.

Cell-based strategies for vascular regeneration

Vascular regeneration is known to play an essential role in the repair of injured tissues mainly through accelerating the repair of vascular injury caused by vascular diseases, as well as the recovery of ischemic tissues. However, the clinical vascular regeneration is still challenging. Cell-based therapy is thought to be a promising strategy for vascular regeneration, since various cells have been identified to exert important influences on the process of vascular regeneration such as the enhanced endothelium formation on the surface of vascular grafts, and the induction of vessel-like network formation in the ischemic tissues. Here are a vast number of diverse cell-based strategies that have been extensively studied in vascular regeneration. These strategies can be further classified into three main categories, including cell transplantation, construction of tissue-engineered grafts, and surface modification of scaffolds. Cells used in these strategies mainly refer to terminally differentiated vascular cells, pluripotent stem cells, multipotent stem cells, and unipotent stem cells. The aim of this review is to summarize the reported research advances on the application of various cells for vascular regeneration, yielding insights into future clinical treatment for injured tissue/organ.

Low CD34+ cells, high neutrophils and the metabolic syndrome are associated with an increased risk of venous thromboembolism

The relationship between MetS (metabolic syndrome), levels of circulating progenitor/immune cells and the risk of VTE (venous thromboembolism) has not yet been investigated. We studied 240 patients with previous VTE and 240 controls. The presence of MetS was identified according to NCEP ATP III guidelines and flow cytometry was used to quantify circulating CD34+ cells. VTE patients showed higher BMI (body mass index), waist circumference, triacylglycerol (triglyceride) levels, blood glucose, hs-CRP (high-sensitivity C-reactive protein) and lower HDL-C (high-density lipoprotein cholesterol) levels. The prevalence of MetS was significantly higher in VTE (38.3%) than in control individuals (21.3%) with an adjusted OR (odds ratio) for VTE of 1.96 (P=0.002). VTE patients had higher circulating neutrophils (P<0.0001), while the CD34+ cell count was significantly lower among patients with unprovoked VTE compared with both provoked VTE (P=0.004) and controls (P=0.003). Subjects were also grouped according to the presence/absence of MetS (MetS+ or MetS−) and the level (high/low) of both CD34+ cells and neutrophils. Very high adjusted ORs for VTE were observed among neutrophils_high/MetS+ (OR, 3.58; P<0.0001) and CD34+_low/MetS+ (OR, 3.98; P<0.0001) subjects as compared with the neutrophils_low/MetS− and CD34+_high/MetS− groups respectively. In conclusion, low CD34+ blood cell count and high circulating neutrophils interplay with MetS in raising the risk for venous thromboembolic events.